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排序方式: 共有2349条查询结果,搜索用时 15 毫秒
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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
5.
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
6.
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
7.
Rosario?Zamora Gemma?Gómez Francisco?J.?HidalgoEmail author 《Journal of the American Oil Chemists' Society》2002,79(3):267-272
13C NMR spectra of oil fractions obtained chromatographically from 109 vegetable oils were obtained and analyzed to evaluate
the potential use of those fractions in the classification of vegetable oils and to compare the results with the NMR analysis
of complete oils. The oils included the following: virgin olive oils from different cultivars and regions of Europe and north
Africa; “lampante” olive, refined olive, refined olive pomace, hazelnut, rapeseed, high-oleic sunflower, corn, grapeseed,
soybean, and sunflower oils; and mixtures of virgin olive oils from different geographical origins. Oils were divided into
two sets of samples. The training set (98 samples) was employed to select the variables that resulted in significant discrimination
among the different oil classes. By using stepwise discriminant analysis, more than 98% of correct validated assignments were
obtained; these results were confirmed when applied to the test set (11 blind samples). Results suggest that the use of oil
fractions considerably increases the discriminating power of NMR in the analysis of vegetable oils. 相似文献
8.
潘劲松 《湖南工业大学学报》2010,24(2):22-26
通过对实验数据的分析,用拟合和逐步回归的方法建立了最优配比方案的数学模型并进行了求解,所得结果与实验数据基本吻合,具有合理性。 相似文献
9.
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
10.
水电站月度调度函数的模型制定与模拟结果评价 总被引:1,自引:0,他引:1
基于统计学中多元逐步回归原理建立了多年调节水电站分月调度函数模型,并根据水电站优化调度特征确定待选自变量,用以指导电站实际优化调度运行。在考虑电站自身各约束及综合利用要求的前提下,进一步采用程序设计模拟调度函数指导水电站长系列调度运行,通过对模拟结果的全面评价,证实所建立的调度函数具有良好的指导意义和实用价值。 相似文献