铜尾渣替代粘土制备水泥熟料的试验研究

以铜尾渣替代粘土配料煅烧水泥熟料,研究了生料的易烧性,测定了熟料的f-CaO含量,采用岩相分析、XRD、SEM等手段,对水泥熟料的矿物组成、强度、水化产物等进行分析研究,探讨了铜尾渣的作用机理.结果表明:铜尾渣对水泥熟料的烧成和矿物形成有较好的促进作用,掺入铜尾渣后,熟料f-CaO含量降低,有效提高了生料的易烧性.掺入铜尾渣煅烧的熟料中C3S和C2S矿物含量多,结晶度好,熟料水化后水化程度好,孔隙少,结构致密,强度高.当煅烧温度为1400℃时,也能煅烧出质量良好的熟料,3d和28 d强度可高达61.4 MPa和114.2 MPa.     

协同处置钨渣替代水泥钙质原料的研究

结合水泥窑系统运行情况,研究了协同处置钨渣对水泥熟料质量的影响,及其替代钙质原料的可行性,并解决其环境污染问题。结果表明：利用水泥窑协同处置氧化钙含量在36%左右的钨渣,处置量控制在5 t/h以内,可替代水泥钙质料,原料替代率达1.8%,且煅烧、熟料质量及其岩相状况良好。处置过程需做好配伍计算、加强过程控制并严格执行相关标准规范,钨渣中磷的掺入可改善生料的易烧性,且其重金属含量不会造成二次污染。     

水泥生料易烧性与熟料煅烧效率

对于水泥来讲,生料的易烧性会直接影响到熟料的煅烧效率,并且生料的易烧性也会对熟料的烧成热耗和窑的产量产生非常大的影响。在目前的水泥烧窑的过程当中,经常加入改良剂来提高熟料的煅烧效率。本篇文章通过对水泥生料易烧性与熟料煅烧效率进行分析研究,并且提出一定意见,为水泥熟料的煅烧效率提供意见参考。     

镁渣配料煅烧熟料形成过程的试验研究

对不同镁渣掺量的生料在不同温度下进行煅烧试验，分析了煅烧料的游离氧化钙，利用XRD分析了煅烧料的矿物组成，并进行了岩相分析。结果表明：掺镁渣生料易烧性较好，熟料矿物岩相结构及形貌正常，熟料矿物形成过程与采用天然原料的基本相同。     

电石渣100%代替石灰石煅烧水泥熟料易烧性的研究

对新疆A厂电石渣100％代替石灰石新型干法煅烧水泥熟料的易烧性进行研究表明,电石渣100％代替石灰石煅烧水泥熟料,生料易烧性好;在配料率值相同的条件下,不同硅质原料对生料易烧性的影响很小;水泥熟料28d强度符合52．5硅酸盐水泥国家标准。     

协同处置危固废过程中熟料频繁结球的分析处置

分析了水泥窑协同处置危固废过程中出现的窑内熟料三次结球情况,检测了熟料球的化学成分和物理性能,分析了入窑生料与熟料化学成分、生料分解率控制、协同处置危固废化学成分和微量重金属含量及含氟化钙污泥加入等对熟料煅烧工艺的影响。通过采取稳定生料和熟料化学成分、适当降低生料Fe₂O₃含量及入窑热生料分解率,加强Cl^-、R₂O等有害成分的控制等措施,同时,在配料和煅烧过程中充分考虑危固废加入对改善生料易烧性的影响,有效解决了水泥窑协同处置过程中熟料频繁结球的问题。     

采用高镁石灰石配料改善生料易烧性的探讨

HR25001／d预分解窑水泥生产线于2002年投产，原采用石灰石、页岩、砂岩和硫酸渣4组分配料，石灰石氧化钙含量基本在54％以上，品位较高，杂质含量较少，结构致密，易烧性反而不好。加之页岩和砂岩结晶硅含量较多，生料易烧性较差，熟料质量一直不理想。另外几个石灰石矿均毗邻风景区，出于保护环境的原因近年来开采量被严格限制。为了改善生料的易烧性并打破石灰石供应的瓶颈，厂部决定采用邻近价格较低但氧化镁含量较高的黑石灰石进行部分替代，考虑到过高的氧化镁可能会对煅烧工况和熟料质量产生较大影响，决定先组织试生产，并特地选择在窑系统中修后进行，以避免干扰。     

生料易烧性指数K1450的计算和影响因素研究与应用实践

生料易烧性指数K1450是一个与C3S形成化学反应速度常数成正比的技术参数,可根据配入煤灰掺入量后的生料化学成分及1 450 ℃煅烧样品的f-CaO含量进行计算。K1450值越高,表明生料易烧性越好;其显著性影响因素包括生料中粗颗粒石英含量、氟离子含量、熟料设计的液相量和铝率。根据K1450数值高低,可以比较准确地预测水泥窑熟料煅烧热耗的相对变化;当K1450从30提高至70,熟料煅烧热耗可降低10%以上。易烧性较好的生料（K1450>70）,由于可在更快的升温速率和更短的高温带通过时间下实现熟料烧成,且可显著减轻窑内还原气氛,因此熟料煅烧热耗较低;若通过进一步优化,使熟料中的A矿能够获得合理的晶体大小及矿物形貌,可显著提高熟料的活性。     

水泥生料易烧性影响因素探究

水泥生料易烧性与生料粒度、原材料特性、熟料煅烧制度等因素相关。文中从硅率、细度、饱和比、石英含量等4个方面探究各因素对生料易烧性的影响规律。研究表明,通过改善易烧性可很好地控制水泥熟料的煅烧过程,有助于水泥生产线的节能降耗和提高产品质量。     

镍渣替代铁粉制备道路硅酸盐水泥

以镍渣替代铁粉制备道路硅酸盐水泥熟料,研究了生料的易烧性,测定了熟料的f-CaO含量,采用X射线衍射,扫描电子显微镜等手段,对水泥熟料的矿物组成、强度、水化产物等进行了分析研究.结果表明:掺入适量镍渣煅烧的熟料f-CaO含量较低,生料的易烧性良好;熟料水化后水化程度好,有较高的抗折强度.当镍渣掺入量为10%,煅烧温度为1370 ℃时,28 d抗压强度可达75.2 MPa,抗折强度可达11.2 MPa.     

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.     

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.     

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.     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.