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Atar Musa Keskin Hakan Güçlü Yavuzcan H. 《Journal of Coatings Technology and Research》2004,1(3):219-224
The impacts of impregnation and bleaching on the varnish layer hardness of Oriental beech (Fagus orientalist L.) wood were investigated. A number of bleaching combinations {[NaOH−H2O2], [NaOH−Ca(OH)2−H2O2], [NaOH−MgSO4−H2O2] [NaHSO3−H2C2O4], [NaSiO3−H2O2], [KMnO4+NaHSO3+H2O3]} were applied at 18% concentration for bleaching to both impregnated and unimpregnated specimens of Oriental beech wood.
Subsequently, water-based (WB) varnish was coated over the samples and the varnish layer hardness values were determined in
accordance with ASTM D 4366-95.
All of the chemicals used for bleaching reduced the surface hardness. However, after varnish coating, the hardness of most
samples was similar to that of the varnish-coated natural (control) samples. 相似文献
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In this study, a kinetic model of the final bleaching stage with hydrogen peroxide in a totally chlorine free (TCF) bleaching sequence for ALCELL® processed pulp was developed. The model was based on the rate of chromophore destruction characterized by the decrease in the light absorption coefficient of bleached pulp at 457 nm, CK. Based on the fact that the chromophore destruction proceeds rapidly in an initial phase followed by a much slower reaction during which a “floor-level” chromophore concentration is approached asymptotically, we propose that the hydrogen peroxide stage of the ALCELL® derived pulp in the studied TCF sequence consists of two distinct phases. The initial phase is a very fast reaction. The rate equation of the second phase was determined as: which is valid in a pH range of 10.5 to 11.5 and a temperature range of 60 to 92.5°C. 相似文献
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The disposal and re-use of spent bleaching clay from the vegetable oil processing industry is a problem of growing importance.
Although today the only practical way of removal of the spent material is disposal, extraction with organic solvents is a
well-known method of de-oiling contaminated bleaching clay. In our investigations we compare the extractibility of two different
types of bleaching clays with CO2 as a solvent. All experiments were carried out with a high-pressure extraction plant. The extraction and separation conditions,
temperature and pressure, as well as the CO2 mass flow, were varied during experiments. The aim of our investigations was a complete separation of the oil from the adsorbent.
The latter should then be re-used as bleaching clay. The oil and the bleaching clay were analyzed and tested, respectively.
The results show that oil of good quality can be recovered and the bleaching clay still has an activity approximately 50%
of fresh clay. 相似文献
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二氧化氯的生产和应用评述 总被引:17,自引:1,他引:17
详细评述了 2 0世纪二氧化氯的主要生产工艺和制备方法及二氧化氯作为漂白剂、消毒杀菌剂、水处理剂等在多种行业中的应用 ,分析展望了 2 1世纪二氧化氯的生产和应用前景 ,认为应在我国大力发展二氧化氯的生产并促进其应用。 相似文献
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文章对作者自制的非硅型氧漂稳定剂SHT进行了双氧水的稳定性试验,结果表明:稳定剂SHT能耐强碱和高温,适用于常规的双氧水漂白工艺,可单独使用;可在硬水中使用,尤其是在Ca2+、Mg2+浓度较高的情况下,对Ca2+、Mg2+等离子仍然具有螯合作用;能克服产品在织物前处理过程中出现的各种质量问题,高效地保证设备的正常运转;并且采用稳定剂SHT能够缩短工艺流程,各项应用性能优异,综合成本低,是目前市场上不可多得的非硅型双氧水稳定剂。 相似文献
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姜生 《南通纺织职业技术学院学报》2010,10(3):1-4
在亚麻织物前处理加工过程中较难去除的是亚麻麻皮木质素,针对亚麻织物前处理工艺中亚麻麻皮的漂白或去除难易程度进行了试验,并探讨了原色纱亚麻织物中麻皮木质素漂白或去除适用的加强煮练、氯漂、酸洗等工艺方法. 相似文献