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111.
112.
阐述了塑料结构壁管的基本情况和国内外现状.重点就扬子石油化工股份有限公司研究院研制的聚丙烯结构壁管专用料的情况进行了介绍。 相似文献
113.
114.
Alper Sarıoğlan Ömer Tunç Savaşçı Ayşe Erdem-Şenatalar Vu Thu Ha Gilbert Sapaly Younès Ben Taârit 《Catalysis Letters》2007,118(1-2):123-128
MFI type inorganic carrier was used in two different cationic forms, hydrogen and calcium respectively. MFI-supported molybdenum
and rhenium catalysts were prepared. The activities of the catalysts were compared for the aromatization reaction of methane.
Higher activity values were attained with the catalysts supported on HZSM-5. Aromatics were also observed with the catalysts
supported on CaZSM-5, despite their deficiency in acid sites. Highly dispersed rhenium is expected to be formed with the use
of the inorganic carrier in calcium form. On the other hand, lower reaction rates were observed with rhenium supported on
CaZSM-5, in spite of the improved dispersion of the active rhenium species on this catalyst. This was interpreted in terms
of the critical role of the acid sites in the conversion of methane to aromatics, compared to the improved dispersion of the
active metal. 相似文献
115.
E.I. Vargha-Butler T.K. Zubovits D.R. Absolom A.W. Neumann H.A. Hamza 《Chemical Engineering Communications》1985,33(5):255-276
The sedimentation volume, Vsed, of coal particles in mixtures of pairs of non-polar and more polar organic liquid combinations as well as in aqueous solutions was determined at 20°C.
The liquid combinations were chosen such that the surface tension, γSV, of the coal particles fell between the surface tensions, γLV, of the two liquids. A constant mass of a given coal sample was suspended in constant volumes of liquid mixtures of different concentrations.
It was found that the sedimentation volume changed with varying composition of the liquid mixtures, as did the surface tension. A maximum or a minimum occurred in Vsed when the surface tension of the suspending liquid was equal to that of the coal particles, i.e. when γLV = γSV. Maxima occurred in more polar and minima in the non-polar or less polar liquid mixtures. The position of the extrema, and hence the surface tension, γsv, of the particles, was found to change with particle size, in agreement with findings from other independent techniques.
It was found that the surface tension of coal, γsv, depends on the surrounding liquid, i.e. coal is hydrophobic in organic and hydrophilic in aqueous media, again in agreement with the results from other techniques. 相似文献
The liquid combinations were chosen such that the surface tension, γSV, of the coal particles fell between the surface tensions, γLV, of the two liquids. A constant mass of a given coal sample was suspended in constant volumes of liquid mixtures of different concentrations.
It was found that the sedimentation volume changed with varying composition of the liquid mixtures, as did the surface tension. A maximum or a minimum occurred in Vsed when the surface tension of the suspending liquid was equal to that of the coal particles, i.e. when γLV = γSV. Maxima occurred in more polar and minima in the non-polar or less polar liquid mixtures. The position of the extrema, and hence the surface tension, γsv, of the particles, was found to change with particle size, in agreement with findings from other independent techniques.
It was found that the surface tension of coal, γsv, depends on the surrounding liquid, i.e. coal is hydrophobic in organic and hydrophilic in aqueous media, again in agreement with the results from other techniques. 相似文献
117.
比重瓶法与密度仪法测定香精密度相关性的回归分析 总被引:1,自引:0,他引:1
目前测定香精密度的方法主要有标准传统法-比重瓶法和密度仪法。用这两种方法测得的结果一致与否,为探求这两者之间相关关系的密切程度和表现形式,通过测定系列香精的密度,并对所得数据进行线性相关和回归分析,得出了比重瓶法与密度仪法所得结果的相关方程。利用该方程可以由密度仪法测得的结果计算出比重瓶法的密度,经计算出的结果与标准方法比较一致。通过回归方程,可以用密度仪法代替标准法来测定香精的密度。 相似文献
118.
The influence of HAF carbon black and BaTiO3 ceramic powder contents in SBR vulcanizates on the dielectric constant (ε′) at different frequencies and at fixed temperature of 303 K is studied well in this article. The temperature dependence of the ac conductivity (σac) was also studied. ε′ appreciably decreases as frequency increased for both filled and unfilled SBR vulcanizates. At each frequency, ε′ gradually decreased with BaTiO3 loading, but its change at any fixed frequency with BaTiO3 filler loading is not uniform. For HAF group ε′ (at loading ≥ 40 phr), drops rapidly with frequency. Meanwhile, it increased appreciably beyond a certain HAF filler loading (≈ 20 phr). Experimental values of the dielectric constant of both BaTiO3 and HAF contents were compared with those calculated by using Tsangaris, Clausius and Bruggman models. Tsangaris model with simple modifications was applied and a fairly good agreement was obtained. The HAF particles or aggregates was found to take the shape of oblate ellipsoids with the minor axes parallel to the applied frequency as detected from the decreasing behavior of the depolarizing factor (Y) with HAF contents. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2227–2234, 2007 相似文献
119.
钢包粘渣与包衬耐火材料 总被引:5,自引:0,他引:5
阐明了钢包粘渣与包衬耐火材料存在一定的关系 ,抗渣渗透性差、容易出现开裂的包衬耐火材料容易粘渣。为防止钢包粘渣 ,适于采用抗侵蚀性和抗渣渗透性优良的尖晶石砖、铝尖晶石 (或铝镁 )浇注料、低密度浇注料以及抗剥落性好的刚玉 -锆英石浇注料作包衬耐火材料 相似文献
120.
广东南华水泥有限公司原煤均化库因生产需要进行了改造,相应地,原煤均化库布料小车的电气控制回路也进行了改造。在改造过程中,该厂充分利用原控制电路和改进后的电路元器件,只增加了若干干簧管和控制开关,稍作改动便达到了控制目的,既科学可靠,又经济实用。 相似文献