高胶凝性水泥熟料

总结了以硅酸三钙(C3S)为主要矿物的熟料烧成研究成果和最新研究进展．C3S是硅酸盐系统的水泥熟料中含量最高、胶凝性能最好的矿物。在熟料烧成过程中。C3S是形成温度最高的矿物。因此。C3S的充分形成实际上也就代表了熟料的烧成．提高C3S含量是提高水泥熟料胶凝性能有效途径．采用离子掺杂的方法可以降低熟料烧成过程中的游离氧化钙,使C3S质量分数(下同)在70%以上的硅酸盐水泥熟料在正常温度下烧成。如：在生料中掺加氟硫复合矿化剂,适量磷渣或钢渣等含磷杂质及其与氟离子复合。或者掺入1%CuO,可明显改善熟料的易烧性。但是磷的掺加数量应有一定限制。在硅酸盐水泥熟料中引入适量硫铝酸盐矿物也可以有效提高水泥的胶凝性能。但是应该解决烧成温度范围偏窄的问题。     

全固废高贝利特-硫铝酸盐水泥熟料矿物的形成研究

以脱硫石油焦渣、粉煤灰及电石渣等工业固体废弃物为主要原料，辅掺少量铝矾土，烧制一种以无水硫铝酸钙（C4A3S）、硅酸二钙（C2S）和铁铝酸四钙（C4AF）为主要矿物的绿色高贝利特硫铝酸盐水泥熟料。利用XRD和TG-DSC相结合的分析方法研究了煅烧温度、煅烧时间及升温速率对水泥熟料烧成的影响。结果表明：该水泥熟料的烧成温度在1?200~1?300 ℃之间，煅烧区间为100 ℃，最佳煅烧温度为1?280 ℃，保温时间45 min及升温速率10 ℃/min，该煅烧条件下制得的水泥熟料1 d、3 d、28 d强度分别可达32.7 MPa、37.5 MPa和58.5 MPa，当煅烧温度高于1?300 ℃或煅烧时间过长时，容易造成C4A3S的分解，从而影响水泥熟料性能。     

氧化铜对硅酸三钙和硫铝酸钙矿物形成及共存的影响

研究了CuO对含硫铝酸钙矿物硅酸盐水泥中硅酸三钙（C3S）和硫铝酸钙（C4A3S）矿物形成及共存的影响。借助化学分析和X射线衍射内标法分别测定了水泥熟料中C3S及C4A3S矿物的含量。用X射线衍射仪分析了熟料矿物组成,并采用差热分析和透射电镜分别研究了CuO对熟料形成特性和C3S晶体结构的影响。研究结果表明：生料中掺入生料质量0．1％的CuO,能降低水泥熟料的烧成温度。促进C3S和C4A3S两种矿物相互共存．提高熟料的强度。过量的CuO亦会降低C4A3S矿物的分解温度。     

烧成温度对C3S型硫铝酸盐水泥熟料矿物形成的影响

本文通过对不同烧成温度制备熟料矿相的分析,研究了烧成温度对C3S型硫铝酸盐水泥熟料矿物形成的影响。结果表明,提高烧成温度利于C3S型硫铝酸盐水泥熟料的烧结,但由于采用高钙配料,以及采用氟化钙、氧化锌复合矿化剂技术,在降低C3S形成温度的同时,也降低了C4A3S的分解温度,从而影响熟料矿物的形成、生长与分解。     

高胶凝性阿利特-硫铝酸钙钡矿相体系的研究

以分析纯化学试剂为原料,对以阿利特与硫铝酸钙钡为主导矿物的高胶凝性矿相体系进行了研究。探讨了体系组成、烧成温度和微量元素对熟料性能的影响。结果表明：C(B)4A3S与C3S等矿物可以通过低温固相反应形成并共存于同一熟料体系中,这为高胶凝性阿利特一硫铝酸钙钡矿相体系的合成奠定了重要基础。在实验所设计的体系组成与制备工艺条件下,确定C(B)4A3S在矿物体系中的适宜质量分数(下同)应低于10％,体系的烧成温度确定为1360℃,当温度达到1390℃时,含硫矿物仍不会分解,预示该熟料具有一定的烧成范围。少量CaF2对提高该体系的力学性能有一定作用,适宜含量为1.0％～1.5％。由该熟料制备的水泥,以0．30水灰比制备的一些样品抗压强度在28d龄期已接近90MPa,展现出良好的前景。采用XRD,SEM／EDS和岩相分析,对熟料的组成、显微结构与形貌进行了分析。     

用脱硫石膏制备硫铝酸盐水泥熟料研究

用脱硫石膏代替天然石膏进行硫铝酸盐水泥熟料制备试验研究.结果表明:用本试验所采用的原料,配料比为m(矾土)∶ m(石灰石)∶ m(脱硫石膏)=35∶ 43∶ 22,煅烧温度为1400 ℃可烧制成矿物组成为无水硫铝酸钙和硅酸二钙的合格硫铝酸盐水泥熟料.从外观特征及借助XRD、SEM分析温度对水泥熟料烧结的影响,当烧结温度为1300 ℃时,熟料结构酥松,强度低,其主晶相为C_4A_3 、β-C_2S、2C_2~-S·CaSO_4,熟料为欠烧料;当烧成温度为1400 ℃时,熟料结构致密,强度高,形成的主要矿物为C_4A_3 、β-C_2~-S和C_4AF,属于正常合格的硫铝酸盐水泥熟料;当烧成温度为1500 ℃时,出现液相过多,熟料块坚硬,主晶相为C_4A_3 、β-C_2~-S、C_12A_7、CT,熟料为过烧料.     

高铁低钙硅酸盐水泥体系的抗氯离子侵蚀性能研究

为了改善水泥基材料的抗氯离子侵蚀性能,提出高铁低钙硅酸盐水泥体系[C4 AF≥18％,C3 S≤50％,层状双氢氧化物材料(LDHs)].分别制备了矿相组成为(18％C4 AF,50％C3 S)及(20％C4 AF,48％C3 S)的高铁低钙水泥熟料,探讨了高铁低钙水泥熟料的烧成制度和材料特性;测试了硬化高铁低钙水泥浆体的3、7、28 d抗压强度及28 d氯离子扩散系数,研究了0％～8％掺量的LDHs对高铁低钙水泥体系的力学性能及抗氯离子侵蚀能力的影响.结果表明,C4 AF含量为20％的高铁低钙水泥熟料比C4 AF含量为18％的高铁低钙水泥熟料的结晶度高;掺LDHs的高铁低钙水泥基材料的3d和7d强度有所提高,当掺量为2％时强度达到最大;高铁低钙水泥体系通过提高水泥熟料中的铁相含量、降低硅酸三钙含量、引入具有离子固化能力的LDHs,显著改善了其抗氯离子侵蚀性能,当LDHs掺量为4％时,高铁低钙水泥基材料抗氯离子侵蚀能力最强.     

三乙醇胺对水泥-粉煤灰体系水化进程与强度的影响机制

为掌握三乙醇胺(TEA)水泥-粉煤灰体系水化与强度的影响规律及其机理,促进粉煤灰的有效利用,采用等温量热法测试分析了不同温度条件下TEA对水泥-粉煤灰体系水化放热行为和体系活化能的变化,通过热重和X射线衍射分析了掺TEA水泥-粉煤灰体系的物相组成及其变化,研究了TEA对水泥-粉煤灰体系水化进程和强度的影响规律.结果 表明,TEA和温度均水泥-粉煤灰体系水化放热和强度发展存在较大影响.TEA提高了粉煤灰在72 h内的反应热,促进了水泥-粉煤灰体系早期的水化放热,并且在高温下更加明显,水泥-粉煤灰体系活化能随着TEA掺量增加而降低,TEA对水泥熟料矿物铝酸三钙(C3A)、硅酸三钙(C3S)和硅酸二钙(C2S)在不同龄期内的水化进程影响不同,TEA在早期对C3A熟料的水化具有明显的促进作用,而对C3S和C2S的水化则有延缓作用.     

Ba在C2S-C3S矿物相中固溶机理探讨

以Ca(OH)2、SiO2、Fe2O3、Al2O3化学纯为原料,分别掺入不同质量分数的Ba(OH)2制备不同矿物相组成的熟料相,运用化学分析、XRD、SEM、水化热测试方法,研究掺Ba(OH)2后熟料相中硅酸三钙-硅酸二钙(C3S-C2S)混合相组成、晶型、新相生成的变化规律.结果表明:Ba(OH)2一定程度上削弱C3S形成,且稳定β-C2S形成效应明显,矿物相体系中α'-C2S、α-C2S量减少并转换为β-C2S,掺量大于2.5％后有新相Ba0.48 Ca1.52SiO4形成;Ba(OH)2掺入促使矿物相中C2S相明显增多,晶粒整体尺寸变小,边界变圆润;随Ba(OH)2掺量递增,熟料样的水化速率呈持续减小的趋势变化.     

高强低钙硅酸盐水泥冷却过程的智能控制技术

<正>1　概述高强低钙硅酸盐水泥,是以硅酸二钙(贝利特,C2S)为主导矿物的新型硅酸盐水泥。硅酸二钙存在α,β,γ三种晶型,在熟料烧成和冷却过程中,高水化活性的α,β晶型容易向几乎没有水化活性的γ型转变,导致熟料粉化和水泥强度锐减。因此,贝利特矿物的稳定与活化技术是制备高强低钙水泥的关键,与传统的硅酸盐水泥相比,高强低钙水泥需要更稳定的生料分解、熟料烧成和快速冷却过程,也就意味着对反应温度、压力、流速等关键过程     

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。