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采用电炉模拟预分解窑热工制度煅烧水泥熟料,并用旋转黏度计和微型坍落度仪等测定水泥浆体的流变性,又利用扫描电镜、水化热等近代测试方法,分析相关的作用机理,研究熟料煅烧时间对水泥浆体流变性的影响。研究结果表明:煅烧熟料的保温时间过短,矿物晶体来不及充分长大,颗粒细小,发育不完善,加快水泥的水化速度,使水泥浆体的流变性变差。 相似文献
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R. Indu Shekar T. M. Kotresh P. M. Damodhara Rao M. N. Satheesh Kumar Siddaramaiah Md. S. Rahman 《应用聚合物科学杂志》2011,122(4):2295-2301
The effect of heat flux levels on burning behavior and heat transmission properties of hybrid fabrics and composites has been investigated using cone calorimeter and heat transmission techniques. The hybrid fabric structures woven out of E‐glass (warp) and polyether ether ketone (PEEK) (weft) and E‐glass (warp) and polyester (weft) have been studied at high heat flux levels keeping in view the flame retardant requirements of structural composites. The performance of the glass–PEEK fabric even at high heat flux levels of 75 kW/m2 was comparable with the performance of glass–polyester fabric evaluated at 50 kW/m2. The results further demonstrate that glass–PEEK hybrid fabrics exhibit low peak heat release rate, low heat release rate, low heat of combustion, suggesting an excellent combination of materials and fall under the low‐risk category and are comparable with the performance of carbon fiber‐epoxy‐based systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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The aim of this study was the optimization of cone calorimeter to determine the burning behavior of textile fabrics. In particular, the combustion behavior of commercial polyester textile fabrics with varying densities was studied in terms of time to ignition (TTI), heat release rate (HRR), and relative peak (pkHRR) were monitored. Reproducibility and repeatability of the data have been verified by the influence of instrument variable including incident heat flux, the temperature of ceramic backing pads and retaining grid used during sample mounting as well as sample weight (as the number of fabric layers), the density of textiles, and the relative humidity. A low reproducibility has been obtained when a wire grid was not used to stabilize samples during the tests. The effects of these variables on TTI and pkHRR were observed. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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(Z,Z)-4,7-tridecadien-(S)-2-yl acetate: sex pheromone of Douglas-fir cone gall midge,Contarinia oregonensis 总被引:1,自引:0,他引:1
Gries R Khaskin G Gries G Bennett RG King GG Morewood P Slessor KN Morewood WD 《Journal of chemical ecology》2002,28(11):2283-2297
Our objectives were to identify and field test the sex pheromone of female Douglas-fir cone gall midge, Contarinia oregonensis (Diptera: Cecidomyiidae). Coupled gas chromatographic–electroantennographic detection (GC-EAD) analyses of pheromone extract revealed a single compound (A) that elicited responses from male antennae. Hydrogenation of pheromone extract, followed by renewed GC-EAD analysis, revealed a new EAD-active compound with chromatographic characteristics identical to those of tridecan-2-yl acetate on five fused silica columns (DB-5, DB-210, DB-23, SP-1000, and Cyclodex-B). Syntheses, chromatography, and retention index calculations of all possible tridecen-2-yl acetates suggested that the candidate pheromone A was a tridecadien-2-yl acetate with nonconjugated double bonds. Synthetic candidate pheromone component (Z,Z)-4,7-tridecadien-2-yl acetate (Z4Z7) cochromatographed with A on all analytical columns and elicited comparable antennal activity. In GC-EAD analyses that separated the enantiomers (Z,Z)-4,7-tridecadien-(S)-2-yl acetate (2S-Z4Z7) and (Z,Z)-4,7-tridecadien-(R)-2-yl acetate (2R-Z4Z7) with baseline resolution, only 2S-Z4Z7 as a component in a racemic standard or in pheromone extract elicited antennal responses. In Douglas-fir seed orchards, sticky traps baited with 2S-Z4Z7 captured male C. oregonensis, whereas 2R-Z4Z7 was behaviorally benign. Comparable catches of males in traps baited with racemic Z4Z7 (50 g) or virgin female C. oregonensis suggested that synthetic pheromone baits could be developed for monitoring C. oregonensis populations in commercial Douglas-fir seed orchards. 相似文献
86.
通过对焦煅烧回窑的一些设计和运行参数的讨论,论述了锥形回转窑的设计及其使用的可行性和优越性。 相似文献
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本文中,我们考察了具有有效决策K-上半连续、K-拟凹映象的存在性条件问题,并且给出了有关此类映象的一个定理,其中映象从仿紧凸空间到有序的拓扑向量空间.定理的证明用到了Brouwer不动点定理. 相似文献