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亚麻/聚丙烯机织复合材料薄板的制备与研究 总被引:8,自引:0,他引:8
本文以聚丙烯长丝作为基体,亚麻纱线为增强体,二者按一定体积含量进行捻合,形成合股纱,采用机织的方法织造亚麻/聚丙烯共织平纹布.选取五层平纹布进行层合热压,制备出亚麻增强聚丙烯(PP)热塑性复合材料薄板.对其拉伸性能进行测试,并分析破坏机理. 相似文献
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Thermal degradation of flax: The determination of kinetic parameters with thermogravimetric analysis
The thermal degradation of flax was investigated with thermogravimetric analysis. The flax used for these experiments underwent different stages of retting or, in one case, boiling. The most retted type of flax was also chemically treated to obtain elementary fibers. These samples were all tested in dynamic and isothermal runs after careful sample preparation. The resulting thermograms were analyzed and later used to calculate the kinetic parameters of cellulose degradation. These kinetic parameters included reaction constants and activation energies. A clear difference in the various tested types of flax was observed through a comparison of these values, and an explanation for these differences was suggested. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2634–2643, 2002 相似文献
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亚麻沤制废水属于高浓度有机废水。该废水有机物浓度COD为4000—10000mg/l,BOD_5为2000—6000mg/l,木质素为130—260mg/l。本文采用上向流厌氧污泥床作为该废水的主要处理工艺,取得了很好的效果。COD的去除率可达到78.1%~95.2%,BOD_5的去除率可达到90.2%~98.7%,木质素的去除率可达到12.5%~51.9%.为后续的好氧处理出水达到国家排放标准,奠定了很好的基础. 相似文献
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Alexander Kanapin Mikhail Bankin Tatyana Rozhmina Anastasia Samsonova Maria Samsonova 《International journal of molecular sciences》2021,22(22)
Modern flax cultivars are susceptible to many diseases; arguably, the most economically damaging of these is the Fusarium wilt fungal disease. Over the past decades international flax breeding initiatives resulted in the development of resistant cultivars. However, much remains to be learned about the mechanisms of resistance to Fusarium infection in flax. As a first step to uncover the genetic factors associated with resistance to Fusarium wilt disease, we performed a genome-wide association study (GWAS) using 297 accessions from the collection of the Federal Research Centre of the Bast Fiber Crops, Torzhok, Russia. These genotypes were infected with a highly pathogenic Fusarium oxysporum f.sp. lini MI39 strain; the wilt symptoms were documented in the course of three successive years. Six different single-locus models implemented in GAPIT3 R package were applied to a selected subset of 72,526 SNPs. A total of 15 QTNs (Quantitative Trait Nucleotides) were detected during at least two years of observation, while eight QTNs were found during all three years of the experiment. Of these, ten QTNs occupied a region of 640 Kb at the start of chromosome 1, while the remaining QTNs mapped to chromosomes 8, 11 and 13. All stable QTNs demonstrate a statistically significant allelic effect across 3 years of the experiment. Importantly, several QTNs spanned regions that harbored genes involved in the pathogen recognition and plant immunity response, including the KIP1-like protein (Lus10025717) and NBS-LRR protein (Lus10025852). Our results provide novel insights into the genetic architecture of flax resistance to Fusarium wilt and pinpoint potential candidate genes for further in-depth studies. 相似文献
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以亚麻短纤维为包覆纤维,涤纶短纤维为芯纱纺制摩擦纺包芯纱,通过三因子二次通用旋转组合试验,研究摩擦辊转速、纺纱速度,以及芯纱比例这3个主要工艺参数对纱线性能的影响,分析得到纺制亚麻短纤维摩擦纺包芯纱的较佳工艺范围。 相似文献
49.
The cell-wall composition has been analyzed for 13 batches of flax fibers grown over 3 years under 3 different weather conditions including a ‘normal one, a harsh drought and a rainy weather. It was found that both stresses, drought and excess of rain induced a decrease of uronic acid in the matrix and an increase of the structuring pectins. Besides, a drought led to an increase of hemicellulose polysaccharides (+24%) whereas an excess of rainfall caused a rise in the amount of so-called structuring pectins (+67%). As the fiber’s mechanical properties remained the same over the years, it was assumed that the cell-wall composition was modified to preserve the mechanical role of the fiber in the stem. 相似文献
50.
Umit Huner 《Journal of Natural Fibers》2018,15(6):808-821
The aim of this study is to examine the impact of surface modification on properties of flax fiber and flax-reinforced composites. For this purpose, acetic anhydride, sodium hydroxide, and silane were used to treat surface of the flax fiber. The effects of treatments on fiber were investigated by using contact angle, attenuated total reflectance-Fourier transform infrared, atomic force microscopy (AFM), and scanning electron microscopy (SEM). Contact angle and AFM results revealed that sodium hydroxide-treated flax fibers have higher adhesion force on the fiber surface. Particularly, NaOH treatment improved the mechanical properties of the epoxy matrix composite. 相似文献