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对纸铝塑复合包装材料中的铝塑分离方法和工艺进行了研究,以苯-无水乙醇-水混合液为分离剂,根据铝塑分离时间、分离率、铝塑总得率,采用三角形坐标图分析法,优化了分离剂中3种组分的体积比及铝塑复合材料分离的最佳工艺;考察了分离剂的温度、三组分的体积比对铝塑分离效果的影响,并对各组分在铝塑分离中所起作用进行了分析研究。结果表明,当分离剂中3种溶剂的体积比V(苯)∶V(无水乙醇)∶V(水)为30∶20∶50、温度60℃、分离时间为5.85 min时,铝塑分离效果最佳,此时分离率为100%,铝塑总得率可达97.46%。通过对塑料分离前后的红外光谱图对比可知,分离剂没有改变塑料的性质。 相似文献
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陕西科技大学造纸工程学院张素风等人,对纸铝塑复合包装材料中的铝塑分离方法和工艺进行了研究,以苯一无水乙醇一水混合液为分离剂,根据铝塑分离时间、分离率、铝塑总得率,采用三角形坐/标图分析法,优化了分离剂中3种组分的体积比及铝塑复合材料分离的最佳工艺;考察了分离剂的温度、三组分的体积比对铝塑分离效果的影响,并对各组分在铝塑分离中所起作用进行了分析研究。 相似文献
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针对混合溶剂处理铝塑复合物工艺的研究,分别以苯-乙醇-水、甲苯-乙醇-水、苯乙烯-乙醇-水3种混合液作为分离剂进行铝塑分离实验。由于苯、甲苯、苯乙烯的溶解度参数相近,当铝塑完全分离时,考察不同分离剂各组分的体积比,通过混合溶剂溶解度参数计算公式得出各混合溶剂的溶解度参数。根据相似相溶原理,得出铝塑复合物间有机胶黏剂溶解度参数的理想范围。结果表明,3种混合溶剂处理铝塑复合物,当铝塑完全分离时,铝塑复合物间胶黏剂的溶解度参数范围为29.1~34.8;甲苯-乙醇-水混合溶剂作为分离剂,所需的甲苯体积比最小(20%)。 相似文献
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试验以花椒籽为原材料,研究无水乙醇浸提法提取花椒籽油的工艺。通过单因素试验和三因素三水平响应面分析试验,优化无水乙醇浸提法提取花椒籽油工艺的工艺参数。研究分别对影响花椒籽油提取工艺的影响因素(料液比、提取温度、提取时间、提取次数)进行单因素试验,获得较优水平因素后选用提取温度、料液比、提取时间进行响应面分析试验,确定了影响花椒籽出油率的大小顺序:提取温度、料液比、提取时间。无水乙醇浸提法提取花椒籽油的最适工艺条件参数:料液比1∶5 (g/mL)、提取温度59℃、提取时间2.7 h,在最佳工艺参数下花椒籽的出油率为23.38%。经过对比,验证值与理论值的相对误差小于5%。该试验为开发花椒籽油的生产提供一定的理论依据。 相似文献
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以桐油通过酯交换反应制得的桐油脂肪酸甲酯为原料,以无水乙醇为溶剂,采用尿素包合法分离其中的C18不饱和脂肪酸甲酯。以C18不饱和脂肪酸甲酯含量和收率为评价指标,探究了尿素用量、无水乙醇用量、包合温度、包合时间对桐油脂肪酸甲酯分离效果的影响。通过正交实验设计优化得到最佳工艺条件。对桐油C18不饱和脂肪酸甲酯的溶剂性能进行了测定。结果表明,尿素用量是影响C18不饱和脂肪酸甲酯含量的主要因素,C18不饱和脂肪酸甲酯制备最佳工艺条件为尿素与桐油脂肪酸甲酯质量比1∶1、无水乙醇体积与桐油脂肪酸甲酯质量比5∶1、包合温度5℃、包合时间18 h,在此条件下C18不饱和脂肪酸甲酯含量可达99. 28%,收率为54. 93%。得到的桐油C18不饱和脂肪酸甲酯的闪点(190℃)、沸点(320℃)高,有机挥发物未检出,贝壳松脂丁醇值(KB)为59,证明其是一种环境友好型溶剂。 相似文献
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泡沫分离技术因其具有低浓度下效率高、成本低和无污染等优点在降低蛋白质分离成本方面具有巨大的潜力。但气-液界面诱导的蛋白质变性能显著降低蛋白质的分离效果,这严重限制了泡沫分离技术在蛋白质分离领域的工业化应用。为了解决这一难题,在列举了泡沫分离过程中普遍存在的蛋白质变性现象的基础上,首先从分子和泡沫水平对泡沫分离过程中蛋白质变性机理的研究现状进行了介绍,并总结、分析和对比了泡沫分离过程中蛋白质变性机理的分子水平研究方法。其次,将泡沫分离过程中蛋白质变性的抑制方法分为分离前的抑制和分离后的复性两类,在介绍这两类方法研究现状的基础上对其进行了分析和对比,指出后者更有利于蛋白质泡沫分离效果的提高。最后提出了泡沫分离蛋白质在分子水平上的研究仍十分薄弱,并指出了解决气-液界面诱导蛋白质变性和蛋白质界面吸附之间的矛盾是提高泡沫分离效果的关键,并对其未来可能的研究方向进行了展望。 相似文献
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Hemicellulases used in the wheat separation process have resulted in better separation, purer fractions, increased plant capacity, reduced processing time etc. In order to further improve enzyme-treatment in the wheat separation process, monocomponent xylanases were evaluated. A laboratory viscosity model has been set up to evaluate the xylanases. The model showed good correlation (for a commercial hemicellulase preparation used for wheat separation) between viscosity of the wheat flour slurry and the sludge/supernatant ratio after centrifugation of the slurry. A xylanase (Novozyme 867) with excellent performance in the wheat separation process has been found. The xylanase has high activity towards soluble arabinoxylan and gives a rapid viscosity reduction of wheat flour slurries. The enzyme also has a moderate activity towards insoluble arabinoxylan, but due to the low molecular weight of the solubilized material this was not was found to contribute negatively to the enzymes' performance. The pH and temperature conditions in the wheat separation process were well within the active range of the enzyme. A pilot plant experiment showed improved yield of gluten and A-starch, with no apparent negative effect on the gluten quality. 相似文献
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填充柱超临界CO2流体色谱是近年发展的一种绿色高效色谱分离技术。本文采用填充柱超临界CO2流体色谱对外消旋γ-辛内酯、γ-癸内酯、γ-十一内酯、γ-十二内酯4种香料进行制备规模手性拆分。色谱柱Chiralpak AD 250mm×10mm10μm,柱温、柱压、改性剂等参数在前期分析研究基础上设定。调节流动相流速、样品浓度得较佳分离通量,并进行制备性分离,结果:γ-辛内酯,上样2mg/次,每次运行9min,180min分离40mg,回收率(以2个对映体计,下同)66.3%;γ-癸内酯,上样0.8mg/次,每次运行9min,180min分离16mg,回收率68.1%;γ-十一内酯,上样0.8mg/次,每次运行11min,220min分离16mg,回收率64.4%;γ-十二内酯,上样0.7mg/次,每次运行11min,220min分离14mg,回收率71.4%。上述分离制备所得对映体的光学纯度(e.e%)均为100%。 相似文献
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Several methods (e.g., UV/H2O2 oxidation, adsorption, flocculation-precipitation) are normally employed to remove dye from water. A new technique based on liquid/liquid extraction using reverse micelles is proposed whereby recovery of solvent and reuse of dye is possible. Experiments were conducted by mixing a known quantity of dye in aqueous phase and solvent-containing surfactants in a simple mixer. The separation of solvent phase, containing encapsulated dye in reverse micelles, from aqueous phase due to gravity results in separation of dye from water. The removal of different ionic dyes (e.g., eosin yellow, methylene blue, malachite green, methyl orange, orange G) from aqueous phase in the presence of different cationic and anionic surfactants [e.g., sodium dodecylbenzene sulfonate, sodium bis(2-ethylhexyl) sulfosuccinate, hexadecyltrimethylammonium bromide, and cetyl pyridinium chloride] in different solvents (e.g., amyl alcohol, benzyl alcohol, methyl benzoate, and isooctane) were studied by conducting experiments. The percentage removal of dye from aqueous phase increases with the decrease in dye concentration or with the increase in surfactants concentration. Furthermore, the percentage COD removal of dye is increased with the increase in surfactant concentration. The nature of solvent has minimal effect on percentage removal of dye. The ratio of solventto aqueous phase volume required for the removal of dye decreases with the increase in surfactant concentration. It is possible to back-extract dye into aqueous phase and recover solvent by using counterionic surfactants. The separation of aqueous phase from the aqueous-phase solvent dispersion is faster for amyl alcohol as compared to benzyl alcohol and methyl benzoate. A theoretical model based on ion-exchange reaction between surfactants and dye is used to analyze the experimental data. 相似文献
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随着颜色复制精度的提高,含有浅色墨的多通道喷墨打印系统使用范围越来越广,但是含浅色墨的喷墨打印系统墨色维度高,光谱冗余严重,分色数据量较大、灵活性不高,且由于同色油墨间的相关性,映射精度对分色精度影响较大。针对这些问题,本研究在色域划分思想的基础上,基于分区纽介堡方程理论,结合灰成分替代原理以及两种色墨替代原理,建立了CMYKcmk两种色墨喷墨打印系统的分色计算模型。结果表明本方法能够减少分色计算量,提高分色可调整性,较好地实现两种色墨喷墨打印分色。 相似文献
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浊点萃取技术及其在食品工业中的应用 总被引:7,自引:0,他引:7
本文介绍了一种新型液-液萃取方法——浊点萃取;讨论了浊点萃取的影响因素;介绍了浊点萃取在分离和纯化生物大分子,萃取金属离子及有机小分子及在食品工业的应用情况。 相似文献
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分别用常规大口径、中口径和细口径毛细管柱色谱测定白酒微量组分,总结了优化色谱条件及柱分离效果的评价,并以典型白酒为例,探讨了部分组分数据的精密度与准确度。结果表明,使用常规细口径柱不仅分离效果好,且分析速度快,定量结果可靠。 相似文献
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G. D. Vareli P. G. Demertzis K. Akrida-Demertzi 《European Food Research and Technology》1998,207(2):122-127
Inverse gas chromatography was used to study the adsorption of water and ethanol on two starchy (cornmeal and wheatflour) and one cellulosic (wheat straw) substrate, in the temperature range 50–90??°C. Three particle size fractions of each substrate were investigated – 180–250?μm, 160–180?μm and 125–160?μm, denoted, respectively, by: 60–80 mesh, 80–100 mesh and 100-120 mesh. Values for the separation factor and for thermodynamic parameters, such as Gibbs free energy and enthalpy of adsorption, were calculated from the chromatographic retention data. The results showed that water was adsorbed more strongly than ethanol on all substrates, at all temperatures. In addition, it was found that lower temperatures were more favourable for the adsorption of both solutes. There was no significant difference between values of separation capacity of the three fractions of wheat straw. In contrast, the separation capacities of starchy materials with smaller particle sizes, i.e. 80–100 mesh and 100–120 mesh, were greater. The 100–120 mesh wheatflour fraction exhibited the highest separation at all temperatures. 相似文献