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Melon seeds are an important source of bioactive compounds, which are considered to be health beneficial. Therefore, the objective of this work was to assess the impact of gaseous ozone treatments (30 and 60 min) on melon seeds paste (nonedible part) and compare with the effect on pulp (edible part). Ozone treatments were evaluated in terms of physicochemical (color, pH, and soluble solids content) and nutritional profiles (total phenolics, total carotenoids, and total antioxidant capacity) of processed material. Results indicate that ozone has a different impact on the two fruit matrices, being seeds less affected by this preservation treatment. 相似文献
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在漂白前进行氧脱木素,能在降低废液污染负荷的同时,还可提高浆的白度,采用CE0HP程序,仍可使思茅松硫酸盐浆在试验条件下达到85%(SBD)的高白度水平。红外光谱分析表明,共轭羰基和非共轭羰基等发色基团的破坏和羰基羟基等助色基团的削弱,是提高纸浆白度的主要原因。 相似文献
15.
Rip G. Rice Ph.D. 《臭氧:科学与工程》2002,24(1):1-15
As we enter this new century, it is striking how the number of applications for ozone is growing. During ozone's first century, the emphasis for using it involved primarily, potable water treatment, wastewater treatment, bottled water treatment, odor control and medical therapy. Of these, potable water and wastewater treatment now can be called the “classical” applications for ozone. But there are a great many more uses for this versatile chemical that might be termed “non-classical”, and these began emerging toward the end of the last century. Some of these so-called “non-classical” developing applications for ozone will be reviewed in this paper. As we enter the 21s1 century, applications for ozone in the various aspects of the agricultural and food processing industries are very active and most promising. 相似文献
16.
Synthesis of SiC nanorods from bleached wood pulp 总被引:1,自引:0,他引:1
Yongsoon Shin Chongmin Wang William D. Samuels Greg J. Exarhos 《Materials Letters》2007,61(13):2814-2817
Unbleached and bleached soft wood pulps have been used as templates and carbon precursors to produce SiC nanorods. Hydrolyzed tetraethylorthosilicate (TEOS), silicic acid was infiltrated into the pulps followed by a carbothermal reduction to form SiC nanorods at 1400 °C in Ar. Residual carbon formed along with SiC was removed by gasification at 700 °C in air. The SiC materials prepared from unbleached pulp were non-uniform SiC with a thick SiO2 coating, while the SiC nanorods prepared from the bleached pulp were uniform and straight with dimensions of 250 nm in diameter and 5.0 mm long. The formation of uniform camelback structure of SiC in the reaction between silica and bleached pulp is attributed to more silica deposited in the amorphous region of cellulose. 相似文献
17.
Gonçalo Figueira Maristela Oliveira Santos Bernardo Almada-Lobo 《Computers & Operations Research》2013
Mathematical formulations for production planning are increasing complexity, in order to improve their realism. In short-term planning, the desirable level of detail is particularly high. Exact solvers fail to generate good quality solutions for those complex models on medium- and large-sized instances within feasible time. Motivated by a real-world case study in the pulp and paper industry, this paper provides an efficient solution method to tackle the short-term production planning and scheduling in an integrated mill. Decisions on the paper machine setup pattern and on the production rate of the pulp digester (which is constrained to a maximum variation) complicate the problem. The approach is built on top of a mixed integer programming (MIP) formulation derived from the multi-stage general lotsizing and scheduling problem. It combines a Variable Neighbourhood Search procedure which manages the setup-related variables, a specific heuristic to determine the digester's production speeds and an exact method to optimize the production and flow movement decisions. Different strategies are explored to speed-up the solution procedure and alternative variants of the algorithm are tested on instances based on real data from the case study. The algorithm is benchmarked against exact procedures. 相似文献
18.
强韧包装纸板用落叶松半化学浆的研究 总被引:1,自引:0,他引:1
主要研究一种可以替代传统硫酸盐化学木浆,来生产强韧包装纸板或瓦楞纸箱箱板纸的落叶松碱性亚硫酸盐-蒽醌半化学浆。这种采用碱性亚硫酸盐添加蒽醌助剂的制浆方法研制的落叶松半化学浆,当纸浆得率为56.9%时,在低打浆度情况下纸浆强度性能可以达到我国2号未漂硫酸盐化学木浆的标准,而且有可能达到1号未漂硫酸盐化学木浆的标准,纸浆得率比落叶松硫酸盐木浆得率实际指标(43%)绝对值提高13%以上。用于制作强韧包装纸板或瓦楞纸箱箱板纸的落叶松碱性亚硫酸盐-蒽醌半化学浆,蒸煮终点宜于控制在得率约62%、卡伯值100左右。 相似文献
19.
Leiviskä T Nurmesniemi H Pöykiö R Rämö J Kuokkanen T Pellinen J 《Water research》2008,42(14):3952-3960
Pulp and paper mill wastewater was characterizated, before (influent) and after (effluent) biological wastewater treatment based on an activated sludge process, by microfiltration (8, 3, 0.45 and 0.22mum) and ultrafiltration (100, 50, 30 and 3kDa) of the wastewater samples into different size fractions. Various parameters were measured on each fraction: molecular weight distribution (MWD) using high performance size exclusion chromatography (HPSEC), total organic carbon (TOC), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total phosphorus (Tot-P), phosphate phosphorus (PO(4)-P), electrical conductivity, pH, turbidity, charge quantity and zeta potential. The MWD, TOC and COD(Cr) results indicated that the majority of the material present in both the influent and effluent was in the medium molecular weight (MW) range (i.e. MW<10kDa) with three main MW sub-fractions. There were no significant differences in the range of the MWD between the influent and effluent samples. The magnitude of the MWD in the effluent was about one half that in the influent, the greatest reduction being in the 6kDa fraction. The 3kDa fractions of both the influent and effluent showed a considerable increase in BOD(7), probably due to the removal of compounds harmful to bacteria in 3kDa ultrafiltration. Influent turbidity decreased considerably in microfiltration (8-0.22mum). As the turbidity was removed by 0.22mum filtration, the anionic charge quantity started to decrease. Particles in the influent and effluent contained 19-29% and 14-20% of the total phosphorus, respectively. The major phosphorus fraction was in the form of soluble phosphate. 相似文献
20.
Abstract The yellowish color of High Yield Pulp (HYP) gives some psychological obstacles and limits its application in some paper grades. Dyes are widely used in the papermaking process to shade the yellowish color of the paper products. We proposed to add dyes into the HYP manufacturing process to minimize the yellowish hue. In this work, we substituted the dye-added HYP (dyes added in the HYP manufacturing process) for hardwood kraft pulp in the production of fine paper grades, and compared the results from those by adding dyes into the papermaking wet end. A higher dye effectiveness was obtained when we used the dye-added HYP. Also, the dye-added HYP gave more effective performance of Precipitated Calcium Carbonate (PCC) fillers and Optical Brightening Agents (OBA) in terms of CIE whiteness and b*. In addition, the dye-added HYP showed less negative effect on brightness and better compatibility with other dyes. The underlying mechanism for the above experimental observation was proposed. 相似文献