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11.
This paper highlights the possibility of inverse gas chromatography for the surface characterization of common fillers (CaCO3, talc, SiO2,) for paints and coatings. Divided solids are described, on the one hand, by the dispersive component of their surface energy and, on the other, by a specific parameter indicating their acid-base interaction potential. The role of the surface morphology at a molecular level is also examined. It is demonstrated that steric effects play an important role in the adsorption of probes on lamellar solids like talc. The consequences of surface treatments as well as examples of practical applications are also reported. 相似文献
12.
A new method using high‐intensity ultrasonic waves, instead of peroxide‐aided reactive extrusion, was applied to modify a linear polypropylene into a branched structure. The ultrasonic waves induced chain scission and created reactive macromolecules of polypropylene successfully in the melt state without any peroxide. To enhance and control the recombination reaction during sonication, a multifunctional agent and an antioxidant were used. The rheological property measurements clearly confirmed that the modified polypropylene had a nonlinear branched structure. It showed shear‐thinning behaviors in its viscosities at low frequencies, high elastic behaviors in Cole–Cole plots, and a high rheological polydispersity index in comparison with a linear polypropylene. The degradation or recombination of polypropylene was adequately controlled by an antioxidant, which stabilized the structure during sonication. Also, the use of an antioxidant was quite effective in improving the extrusion processability by delaying the instability of the extrudate to a higher shear rate. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006 相似文献
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映秀湾水力发电总厂计算机监控系统建设较早,因受当时计算机应用技术限制,使得目前运行的计算机监控系统存在很多不足之处,为此,提出对该系统进行改造的设想,旨在能进一步满足映电总厂“无人值班”(少人值守)和安全经济运行的需要。 相似文献
15.
阐述胜利701气枪震源船震源系统的改造设计。改造设计使胜利701船达到了Ⅱ类航区海船的规范要求,满足了海上三维勘探和高分辨勘探的发展需要,为以后类似船舶的改造提供了经验。 相似文献
16.
Preparation of Compound Ultrafine CeO2 by Wet-Solid-Phase Mechanochemical Modification 总被引:1,自引:0,他引:1
To satisfy practical requirements from industrial applications, an alternate route for synthesis compound ultrafine CeO2 powders by wet-solid-phase mechanochemical modification using industrial grade hydrated cerium carbonate as raw material was proposed.The effect of modifier reaction percentage, reaction time, calcining temperature and modifier amount on particle size, density, suspensibility, and hardness of compound CeO2 powder was investigated.The phase evolutions of preparation process were characterized by XRD.SEM micrograph of the final product shows that compound CeO2 powders obtained are well-dispersed, spherically-shaped, uniformly-sized and submicron-sized particles.The method is readily available in raw material, low in cost, simple in process, and has great potential for industrialization.The compound CeO2 powders of different physical properties can be synthesized by controlling the above-mentioned influence factors in preparation process. 相似文献
17.
催化裂化装置结焦问题的探讨 总被引:9,自引:0,他引:9
针对中国石化股份公司所属56套催化裂化装置近两年半以来由于结焦造成非计划停工的原因,进行分析、探讨并提出了解决办法。指出催化裂化装置的结焦虽然是不可避免的、但通过采取有效措施,可以把结焦对装置安全生产的危害降低到最小程度。 相似文献
18.
两栖装甲装备新型防腐材料的研究 总被引:1,自引:0,他引:1
沿海地区特殊海洋环境造成装甲装备的严重腐蚀,为了研制一种新型的耐蚀有机涂层,该文作者研究了有机硅改性环氧树脂的化学反应,并对改性树脂的性能进行了测试分析.结果表明,改性树脂克服了环氧树脂的耐温性差、亲水性强以及盐水渗透率高的性能缺陷,为进一步制备该地区装甲装备防腐涂料奠定基础. 相似文献
19.
Ahluwalia Jasjit S.; Nollen Nicole; Kaur Harsohena; James Aimee S.; Mayo Matthew S.; Resnicow Ken 《Canadian Metallurgical Quarterly》2007,26(2):214
Objectives: Examine the effectiveness of an intervention to increase fruits and vegetables (FV) consumption among smokers. Design: Cluster-randomized trial of 20 public housing developments; 10 randomly assigned to an FV intervention and 10 to a smoking cessation intervention. Main outcome measures: Usual (past 7 days) and past 30 days change in daily FV intake at 8 weeks and 6 months postbaseline. Results: Greater increases were seen in the FV group. At Week 8 and Month 6, the FV group had consumed 1.58 (p = .001) and 0.78 (p = .04), respectively, more daily FV servings in the past 7 days than the cessation group. At the same time points, the FV group had consumed 3.61 (p = .01) and 3.93 (p = .01), respectively, more FV servings in the past 30 days than the cessation group. Completing more motivational interviewing sessions (p = .02) and trying more recipes (p = .02) led to significantly greater increases at Month 6 among FV participants. Conclusions: Motivational interviewing counseling and lifestyle modification through trying out healthy recipes may be effective in helping a high-risk population increase their FV intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
聚酰胺的改性与加工应用 总被引:1,自引:0,他引:1
本文介绍了有关尼龙树脂材料改性,共聚和新品种尼龙等聚合物设计技术,聚合物合金等复合技术,以DSI等胶粘技术为中心的相关加工技术的动向和具体事例。 相似文献