基于灰色系统理论的磷建筑石膏基胶凝材料组分优化设计研究

以云南磷石膏为主要原料制备磷建筑石膏基胶凝材料.通过应用灰关联分析法分析磷建筑石膏基胶凝材料的组分(复合硅酸盐水泥、普通硅酸盐水泥、矿渣硅酸盐水泥、硅灰、粉煤灰、磷建筑石膏)对其绝干抗压强度的影响,确定了掺合料最佳组合为粉煤灰、矿渣硅酸盐水泥、硅灰;并运用多目标智能加权灰靶决策模型综合考虑抗压强度、抗折强度、初凝时间、终凝时间、软化系数、孔隙率六个指标,确定了其最佳配合比.试验表明:当粉煤灰:矿渣硅酸盐水泥:硅灰:磷建筑石膏的配合比为6%:5%:3%:86%时,其综合性能最好,绝干抗压强度为14.11 MPa,抗折强度为2.58 MPa,初凝时间为16 min,终凝时间为43 min,软化系数为0.51,孔隙率为23%.     

矿物掺合料对硝基β磷石膏的改性研究

研究了粉煤灰、水泥、粉煤灰-石灰、水泥-石灰四种矿物掺合料对硝基β磷石膏的标稠、凝结时间、强度、吸水率和软化系数的影响。结果表明,不同矿物掺合料对硝基β磷石膏物理性能影响不同,粉煤灰的加入使得凝结时间延长,水泥的加入使得凝结时间变短;矿物掺合料会降低硝基β磷石膏强度,仅当粉煤灰-石灰掺入量分别为15%、5%时,抗折抗压强度保持不变;粉煤灰的掺入增大硝基β磷石膏软化系数,水泥可以降低吸水率。     

磷石膏对水泥稳定碎石基层性能影响研究

为掌握磷石膏对水泥稳定碎石基层性能的影响,通过制备不同磷石膏用量的水泥磷石膏稳定碎石试件,并结合室内试验对其无侧限抗压强度、抗压回弹模量和抗裂性能进行研究。研究表明:随着水泥用量增加,水泥磷石膏稳定碎石7d无侧限抗压强度、抗压回弹模量和干缩应变均逐渐增加;随着磷石膏用量增加,水泥磷石膏稳定碎石7d无侧限抗压强度和抗压回弹模量呈先增加后减小趋势,在用量为6%时性能最好,干缩应变则逐渐降低,抗裂性能变好;磷石膏水化过程随龄期增长逐渐深入,故龄期越长其对水泥磷石膏稳定碎石的强度指标提高作用越明显;采用6%磷石膏取代1%水泥制备的水泥磷石膏稳定碎石强度指标和抗裂性能较好。     

水泥基材料对生土改性效果及机制研究

针对当前水泥、矿渣、粉煤灰等无机材料对生土的改性效果主要集中于对其强度和耐久性等宏观性能方面的研究,从改性前后生土的矿物组成、官能团特征峰、微观结构等微观角度来阐述生土改性的内在作用机制.试验结果表明:(1)单掺水泥时,生土改性效果随水泥掺量增加而提高,最佳掺量为15％,其28 d抗压强度和软化系数分别达到9.17 MPa和0.94,原因是Ca(OH)2、C-S-H凝胶等水化产物胶结填充生土颗粒,且在体系中的溶解度趋于饱和;(2)当10％水泥分别复掺5％矿渣和5％粉煤灰时,28 d抗压强度分别达到9.41 MPa和7.14 MPa,软化系数分别为0.90和0.85,其增长的强度来源于矿渣和粉煤灰的二次水化反应,其中的Mg-O、Al-O等键发生断裂,Al3+、Mg2+等阳离子与Ca(OH)2发生置换作用,致使1457.22 cm-1处的特征峰向低波数偏移,同时出现3140 cm-1附近的火山灰反应特征峰;(3)复掺矿渣改性效果优于单掺水泥,而复掺粉煤灰的改性效果不佳.     

粉煤灰聚丙烯纤维材料对污泥固化作用的试验研究

将粉煤灰和聚丙烯纤维按不同比例掺入污泥中,并将所有试样加入相同比例的水泥,养护数天后,对试样开展无侧限抗压强度试验,研究粉煤灰、聚丙烯纤维材料对污泥固化的作用。试验确定了无侧限抗压强度与养护天数、材料掺入比例的关系曲线。试验测得:试样在养护5 d、10 d、20 d、30 d时,5%、10%、15%粉煤灰聚丙烯纤维含量的混合物的无侧限抗压强度值。试验结果显示,由于粉煤灰、聚丙烯纤维的掺入,混合物的无侧限抗压强度均呈增大趋势,且随着粉煤灰、聚丙烯纤维的含量增大而增大;当养护天数增加时,混合物的无侧限抗压强度也随之增大,若继续增大养护天数,混合物的无侧限抗压强度值将会趋于稳定。     

利用硅钙渣、水泥、粉煤灰等改善脱硫石膏制品性能的研究

以脱硫石膏、水泥、高铝粉煤灰及其提铝后硅钙渣为主要原料,制作脱硫石膏制品,并对其性能进行测试。测试结果表明:在脱硫石膏制品中添加水泥可以改善其力学性能以及耐水性能,且水泥的添加量应控制在20%以内;添加硅钙渣的石膏制品与纯石膏相比,密度下降,强度提高,吸水率基本保持不变,软化系数增加,且随着硅钙渣添加量的增加,密度下降加剧;粉煤灰的添加使得制品耐水性提高,但强度降低,吸水率和软化系数提高;生石灰掺量5%时制品强度最高;在粉煤灰、硅钙渣、生石灰总量一定的条件下,改变粉煤灰和石灰石的量,石膏制品的干抗折和抗压强度在10%左右时强度最低。     

磷高强石膏-粉煤灰-石灰的耐水性研究

将粉煤灰及其激发剂石灰加入到磷石膏制备的高强石膏中制备出水硬性的磷石膏粉煤灰石灰(PGFL)复合胶凝材料。通过对比试验研究了石灰、粉煤灰、磷高强石膏(PGHH)掺量对产品软化系数、抗压强度性能的影响,结果表明:加入适量的粉煤灰、石灰可以显著提高PGFL的后期绝干抗压强度和软化系数,提高材料的耐水性,掺量过多则会带来不利影响。     

复合掺配生土改性试验及抗压性能分析

为了推动工业固体废弃物综合利用，改善传统生土材料的力学性能，通过在生土材料中添加煤矸石粉、矿粉、石灰、粉煤灰和麦秸秆灰等5种材料复合掺料进行生土改性试验，依据《土工试验方法标准》(GBT 50123—2019)制备了96个Φ102 mm×116 mm的圆柱体试样，在室内养护28 d后不烘和烘干2种状态下进行轴心抗压试验，得到改性生土试件的荷载-位移关系，分析了复合材料对改性生土抗压强度的影响规律和复合掺料的最优配比。结果表明：煤矸石粉、矿粉、石灰、粉煤灰和秸秆灰掺量分别为0%、8%、6%、8%和2%时，复合材料改性生土试样的28 d抗压强度最大，2种状态下分别达到了3.07、5.07 MPa,与同养护条件的素土试样相比，其分别是其抗压强度的1.71、1.77倍。     

基于土聚水泥生土材料改性试验研究

生土材料是一种传统的古老的生态建筑材料,但由于强度低,耐水性差难以在现代建筑工程中发挥作用.本文提出了一种以偏高岭土作为主要原材料的土聚水泥用于生土材料改性,通过试验分别研究了碱性激发剂掺量、激发剂种类以及促硬剂对土聚水泥改性生土材料力学性能及耐水性影响.研究结果表明,采用浇筑成型的方式,土聚水泥改性生土材料,其28 d抗压强度可达到18.0 MPa,软化系数为0.90.土聚水泥非常适合用于生土材料改性.     

基于含油污泥热解残渣的路基材料制备与性能评价

通过击实试验、无侧限抗压强度试验和水稳性试验研究了水泥、粉煤灰掺量对含油污泥热解残渣路基材料性能的影响.结果 表明:随水泥、粉煤灰掺量的增加,最大干密度和最佳含水量均减小.含油污泥热解残渣路基材料的无侧限抗压强度随水泥掺量的增加而增大,考虑经济性和强度值,选择水泥掺量为4％制备路基材料.随粉煤灰掺量的增加(10％ ～ 30％),无侧限抗压强度先增大后减小,粉煤灰掺量存在最优值(20％).含油污泥热解残渣路基材料的水稳系数随水泥掺量和龄期的增加而增大.     

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。