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81.
A Modified Silane Treatment for Superior Hydrolytic Stability of Glass Reinforced Composites 总被引:3,自引:0,他引:3
A silicon tetrachloride-modified silane treatment of E-glass particles and fibers improved the hydrolytic stability of the glass reinforced composites by creating a water-resistant silane copolymer interphase of approximately 30 Angstroms thickness. SEM observation of E-glass particulate reinforced dimethacrylate-based resin composites showed that strong interfacial adhesion was maintained even under 72 hours of exposure to boiling water, while interfacial adhesion in the conventionally-treated materials was destroyed under the same conditions. Interfacial fracture energy was measured using an embedded single fiber fragmentation test. In the initial dry state, no interfacial debonding was observed in either the modified or conventionally-treated microcomposites, indicating strong interfacial adhesion in both cases. However, after exposure to boiling water for 24 hours, debonding occurred in both cases, with interfacial fracture energies of 281 J/m2 and 54 J/m2 for the modified and conventionally-treated interfaces, respectively. The improvement in hydrolytic stability of the interface is believed to be caused by a higher degree of crosslinking in the silane layer and the replacement of at least some of the hydroxyl groups on the glass surface by covalent O—Si—O bonds. 相似文献
82.
Acidification can both eliminate formation damage and improve flow passage, which can be good for improving single well productivity. Based on this, the authors bring up the thought of moderate acidification technique for sandstone reservoir, and combine it with high pressure packing technique, and one step further, presents a compound sand control technique of high pressure packing and moderate acidification. At the same time, the authors preliminarily discuss the main points of this technique and analyze its mechanism of sand control and yield increase as well as its adaptability. The main purpose of this technique is to clean out the clay and mud in the immediate vicinity of wellbore, decrease the fine content or the particle size in that area, enlarge the seepage channel, and fill in optimized gravel, so as to make it conducive for transpiring the fine sand in the formation and keeping the gravel layer unblocked, as a result making the sand control life prolonged and single-well productivity raised. The keys of this compound technique are moderate acidification and gravel size optimization. 相似文献
83.
Lara Valentín Beata Kluczek‐Turpeinen Pekka Oivanen Annele Hatakka Kari Steffen Marja Tuomela 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):851-858
BACKGROUND: For most dioxin‐contaminated sawmill soils, combustion is recommended. However, the process may be inefficient if the soil has a high organic matter content. The use of saprotrophic basidiomycetous fungi is an alternative for pretreatment of this kind of soil. A total of 147 fungi were evaluated for their ability to grow in sawmill soil. From this screening, the best soil colonizing fungi were selected to study their enzyme activities and degradation of soil organic matter. Pine (Pinus sylvestris) bark was used as a co‐substrate to propagate the fungi into the soil. The activities of manganese peroxidase (MnP), laccase, endo‐1,4‐β‐glucanase, endo‐1,4‐β‐xylanase, and endo‐1,4‐β‐mannanase were analysed from the inocula and fungal treated soil. RESULTS: The screening revealed that 56 out of 147 fungi were able to grow in non‐sterile soil, and most of them were litter‐decomposing fungi (LDF). In pine bark cultures, the highest enzyme activities were observed with Phanerochaete velutina, which produced 5 U g?1 of MnP. The activity of endo‐1,4‐β‐glucanase was generally higher than that of other hydrolytic enzymes. The highest carbon loss from soil with a high organic matter content was achieved by P. velutina (3.4%) and Stropharia rugosoannulata (2.4%). CONCLUSIONS: Many LDF, and in addition the white‐rot fungus P. velutina, are potential degraders of soil organic matter since they showed good growth and respiratory activity. Pine bark was a suitable lignocellulosic co‐substrate and a good promoter of MnP activity. Copyright © 2009 Society of Chemical Industry 相似文献
84.
混凝-缺氧-好氧工艺处理纺织印染废水 总被引:8,自引:1,他引:7
采用混凝--水争酸化--生物接触氧化工艺流程处理纺织印染废水,处理量4000m^3/d,进水COcr1000~3000mg/L、色度4512~1024倍、PH11~13。从1998年7月开始运行至今,CODcr平均去除经为92.32%,色度平均去除率为92.19%,出水P来7,出水各项指标均符合《纺织染整工业水污染物排放标准》GB4287~1992一组标准的要求,运行结果表明,该工艺处理效果稳定、 相似文献
85.
L. Bazinet F. Lamarche D. Ippersiel C. Gendron B. Mahdavi J. Amiot 《Journal of food science》2000,65(8):1303-1307
The purpose of this study was to compare chemical and electrochemical acidification, in order to identify differences between the two acidification procedures. The results reveal differences in the acidification profiles obtained with the two methods. Whereas chemical acidification showed a salting‐in effect from addition of salts, bipolar‐membrane electroacidification (BMEA) removes salts through electrochemical demineralization, favoring protein precipitation. Hence, at pH 4.6, all the caseins were precipitated by BMEA, while some were not yet precipitated by chemical acidification. Nevertheless, the chemical composition and the casein fraction composition of the isolates were the same for both chemical and electrochemical acidification. 相似文献
86.
根据酞菁蓝粗粉生产废水的特点,设计了物化/生化的综合处理工艺,处理出水各项指标均可达到广东省<水污染物排放限值>(DB 44/26-2001)的二级标准. 相似文献
87.
介绍了某染织厂废水处理设施的改造工程.采用水解酸化、接触氧化、混凝气浮工艺处理染织废水,取得了良好的处理效果.运行结果表明,在进水CODCr、BOD5、SS分别为900~1 100、250~350、350~450 mg/L的条件下,出水达到GB 8978-1996一级排放标准. 相似文献
88.
89.
以静电纺丝法制备的聚乙烯吡咯烷酮(PVP)纤维为模板,以非水解溶胶-凝胶法制备的Al2O3溶胶为浸渍液,利用模板浸渍技术制备出Al2O3凝胶-PVP复合纤维,再经1 000℃煅烧制备出γ-Al2O3纤维。借助X射线衍射和扫描电镜研究了浸渍溶胶浓度、浸渍时间及浸渍次数对γ-Al2O3纤维物相组成及形貌的影响。结果表明:当Al2O3溶胶中铝离子浓度为0.1 mol/L、浸渍时间为30 s、浸渍1次时,合成的γ-Al2O3纤维表面平滑,连续性好,纤维直径达到0.22μm。 相似文献
90.