提钛尾渣对硅酸盐水泥水化性能的影响

提钛尾渣是高钛型高炉渣提取合金后的残渣,与铝酸盐水泥的化学、矿物组成相近,具有较好的水化活性.分析不同掺量的提钛尾渣对硅酸盐水泥复合胶凝体系的凝结时间、水化放热、力学性能和水化产物的影响.结果发现,掺量20％提钛尾渣会导致复合胶凝体系早凝,水化初期的水化放热速率加快,累积放热量降低,1 d的水化产物中氢氧化钙减少,单硫型水化硫铝酸钙和三水铝石增多.不同掺量的提钛尾渣均会促进水泥早凝,降低力学性能.随着提钛尾渣掺量的增加,水泥的早凝不明显,力学性能有所增长,水化产物中出现CAH10和C3 AH6的特征峰.     

P·052．5R水泥的生产试验研究

通过小磨试验确定助磨剂的掺加量,在大磨中通过混合材、细度、比表面积、颗粒级配等参数的调整,生产出优质的P·052．5R水泥。试验结果表明,生产优质的P·052．5R水泥控制指标为：混合材掺加量在5％以内、比表面积350m^2／kg左右、细度≤2．5％（R45μm筛余）、3μm-32μm之间的颗粒含量大于70％。另外,还对水泥中掺人矿渣粉进行了试验,试验结果表明：水泥生产中随着矿渣粉的掺入,水泥的3d强度逐渐降低,但掺量在10％以内,水泥的28d强度接近或者高于未掺矿渣粉的试样。当矿渣粉掺量增加到15％时,水泥的28d强度也开始下降。     

含C_4A_3矿物硅酸盐水泥力学性能及水化产物研究

研究了不同水泥厂生产的含C4A3S矿物硅酸盐水泥熟料中掺加不同种类的粉煤灰和矿渣后水泥的力学性能。结果表明:熟料掺加该混合材后的含C4A3S矿物硅酸盐混合材水泥的强度较高;而粉煤灰水泥强度高于同掺量矿渣水泥强度。采用SEM/EDS观察分析水泥水化产物形貌和种类。     

含C4A3(S-)矿物硅酸盐水泥力学性能及水化产物研究

研究了不同水泥厂生产的含C4A3S^-矿物硅酸盐水泥熟料中掺加不同种类的粉煤灰和矿渣后水泥的力学性能。结果表明：熟料掺加该混合材后的含C4A3S^-矿物硅酸盐混合材水泥的强度较高，而粉煤灰水泥强度高于同掺量矿渣水泥强度，采用SEM/EDS观察分析水泥水化产物形貌和种类。     

粉煤灰在串联磨中的应用

利用粉煤灰可以作助磨剂和混合材的2种特性,在生产复合硅酸盐水泥时将粉煤灰按一定比例分别在一级磨和二级磨中粉磨,使水泥磨产量、出磨水泥质量、粉煤灰掺量都有一定程度的提高。     

预处理城市生活垃圾焚烧飞灰作水泥混合材的研究

本文参照水泥常用混合材胶凝活性评定方法对比研究了两种预处理飞灰与粉煤灰、矿渣粉的胶凝活性,并研究了预处理飞灰掺入对水泥性能的影响,确定了适宜的单掺和复掺比例。研究结果表明,预处理垃圾焚烧飞灰可以作为水泥混合材,适宜掺量的预处理飞灰对混合水泥早期水化有促进作用;掺加预处理飞灰后,混合水泥的标准稠度用水量增大,凝结时间缩短;预处理飞灰对混合水泥的体积安定性无不良影响;预处理飞灰与粉煤灰、矿渣粉复掺有助于改善粉煤灰、矿渣粉早期活性低的缺点。     

硅酸盐熟料-煤矸石/粉煤灰混合水泥水化模型研究

对两种不同3CaO·SiO_2(C_3S)含量的硅酸盐水泥和分别掺有30%(质量分数,下同)煤矸石和30%粉煤灰的混合水泥中水化产物含量变化和形态进行了研究,建立了水化产物量变模型和水化产物形态模型,分析了模型的主要特征和意义。相同龄期,高C_3S硅酸盐水泥比低C_3S硅酸盐水泥生成更多的水化硅酸钙(calcium silicate hydrate,CSH)凝胶和氢氧化钙。含混合材的水泥水化时,CSH凝胶在水化早期和后期有两个增长幅度较大的阶段,并且1年后形成的CSH凝胶量与纯硅酸盐水泥的相当。水泥水化产物与混合材的二次水化反应较慢,研究掺有混合材水泥更长龄期的水化产物含量及结构变化,将有助于理解混合材对水泥性能的作用机理。     

钢渣-矿渣复掺作水泥混合材的试验研究

将钢渣粉与矿渣粉以1∶2比例复掺后以30%、50%和80%的掺量用于水泥中,并加入活性激发剂,所配制水泥的各种性能指标满足GB175-2007《通用硅酸盐水泥》的技术要求。分析认为,钢渣粉与矿渣粉复掺提高了颗粒级配的连续性;加入激发剂可以有效促进钢渣的水化,而钢渣的水化又能促进矿渣的水化,提高了钢渣-矿渣复掺粉的活性。钢渣-矿渣复掺粉可以作为混合材大量应用于水泥生产中。     

不同混合材掺量对低碱水泥的适应性试验研究

通过对不同种类及掺量的混合材对低碱水泥流动性能的试验研究,得出:低碱硅酸盐水泥中掺入矿渣粉、粉煤灰、石灰石等混合材有利于改善浆体流动性能,且双掺效果较单掺好;外加剂掺入量对流动性能的改善是随着掺量的增加而增加的.但外加剂的掺入存在一个适宜、经济的掺入量问题;石灰石为非活性混合材,本试验研究结果表明它能显著增大水泥流动性且保持较小的经时损失,但其掺量不宜过大.     

P·O52.5R水泥的生产试验研究

通过小磨试验确定助磨剂的掺加量,在大磨中通过混合材、细度、比表面积、颗粒级配等参数的调整,生产出优质的P.O52.5R水泥。试验结果表明,生产优质的P.O52.5R水泥控制指标为:混合材掺加量在5%以内、比表面积350 m2/kg左右、细度≤2.5%(R45μm筛余)、3μm～32μm之间的颗粒含量大于70%。另外,还对水泥中掺入矿渣粉进行了试验,试验结果表明:水泥生产中随着矿渣粉的掺入,水泥的3 d强度逐渐降低,但掺量在10%以内,水泥的28 d强度接近或者高于未掺矿渣粉的试样。当矿渣粉掺量增加到15%时,水泥的28 d强度也开始下降。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.