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11.
以粉末状新疆胡麻磷脂粗品为原料,经金属离子沉淀法、柱层析法、全溶剂萃取法及薄层层析富集法等工艺制备了高纯度卵磷脂,并研究了金属离子沉淀法对柱层析分离磷脂混合物效果的影响。结果表明:以金属离子锌为复合沉淀离子,以中性氧化铝为吸附剂,以氯仿:甲醇:水=65:25:4(V:V:V)为洗脱剂进行等度洗脱,可获得高纯度的卵磷脂精品;未经金属离子沉淀法处理的磷脂混合物,氧化铝吸附柱层析法无法分离得到单一组分的卵磷脂,对于该部分磷脂混合物,研究采用薄层层析富集法获得卵磷脂纯品。所得卵磷脂采用红外光谱、紫外光谱、一维多次展开薄层层析、二维双液展开薄层层析等手段进行了鉴定。 相似文献
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介绍了天丝、亚麻及其混纺纱的特性,并介绍了在棉纺设备上生产天丝/亚麻65/3518.4tex混纺纱的纺纱工艺流程及纺纱各工序的工艺及措施。 相似文献
14.
亚麻、棉混纺纱纺制过程中,容易出现异性纤维、色差、布面麻粒多、橡皮纱、芝麻纱等质量问题。通过加大对原料的挑拣力度,在清梳并工序充分混合,设备上采取相应改进措施,选择合理的工艺及流程,加强运转管理,控制好各工序温湿度,能有效保证亚麻/棉混纺纱的质量稳定。 相似文献
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油改性醇酸树脂的制备及催化剂对合成工艺影响因素的研究 总被引:3,自引:0,他引:3
探讨了以亚麻油、丙三醇、苯酐为原料制备油改性醇酸树脂的方法及催化剂对合成工艺性能的影响. 相似文献
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亚麻/涤纶/Modal混纺纱纺纱实践 总被引:1,自引:0,他引:1
介绍了亚麻纤维和Modal纤维的特性.详细描述了亚麻纤维、Modal和涤纶混合纺制针织用纱(线)的工艺流程和生产过程中的工艺参数. 相似文献
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Additive manufacturing technologies have a lot of potential advantages for construction application, including increasing geometrical construction flexibility, reducing labor costs, and improving efficiency and safety, and they are in line with the sustainable development policy. However, the full exploitation of additive manufacturing technology for ceramic materials is currently limited. A promising solution in these ranges seems to be geopolymers reinforced by short fibers, but their application requires a better understanding of the behavior of this group of materials. The main objective of the article is to investigate the influence of the microstructure of the material on the mechanical properties of the two types of geopolymer composites (flax and carbon-reinforced) and to compare two methods of production of geopolymer composites (casting and 3D printing). As raw material for the matrix, fly ash from the Skawina coal power plant (located at: Skawina, Lesser Poland, Poland) was used. The provided research includes mechanical properties, microstructure investigations with the use of scanning electron microscope (SEM), confocal microscopy, and atomic force microscope (AFM), chemical and mineralogical (XRD-X-ray diffraction, and XRF-X-ray fluorescence), analysis of bonding in the materials (FT-IR), and nuclear magnetic resonance spectroscopy analysis (NMR). The best mechanical properties were reached for the sample made by simulating 3D printing process for the composite reinforced by flax fibers (48.7 MPa for the compressive strength and 9.4 MPa for flexural strength). The FT-IR, XRF and XRD results show similar composition of all investigated materials. NMR confirms the presence of SiO4 and AlO4 tetrahedrons in a three-dimensional structure that is crucial for geopolymer structure. The microscopy observations show a better coherence of the geopolymer made in additive technology to the reinforcement and equal fiber distribution for all investigated materials. The results show the samples made by the additive technology had comparable, or better, properties with those made by a traditional casting method. 相似文献
20.
Evgenia Kollia Xrisoula Saridaki Dimitrios Karagiannis Vassilis Kostopoulos 《应用聚合物科学杂志》2020,137(13):48787
Present work investigates the effect of hydrothermal aging of flax fiber-reinforced bio-based epoxy resin laminates on the mechanical and thermomechanical properties of the composites. Three different types of bio-based resins were used. Plates reinforced with eight layers plain weave flax fibers of 150 g/m2, manufactured using Resin Transfer Molding (RTM), compression molding or autoclave technique depends on type of the resin. One dimensional Fickian behavior shows a good fitting to the experimental data derived from weight measurements. The water uptake at the equilibrium state in the case of 60 °C temperature was slightly greater than that at 40 °C. The mechanical properties after hydrothermal aging show a significant reduction and do not return to their initial values even after the drying process. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48787. 相似文献