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针对目前秸秆纤维加工中存在能耗大、化学污染严重等问题,研制了依靠物理方法达到清洁制取秸秆纤维的装置。通过对物料特性及螺杆机械结构的分析研究,完成了制取装置关键部件的结构参数确定和整体设计,解决了普通螺杆机械的结构问题,实现了依靠机械方式制取秸秆纤维的目标。 相似文献
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为研究造纸法再造烟叶原料——烟梗、烟末及烟棒的纤维特性,测定了它们的化学成分含量,分析了其纤维显微结构和纤维质量,考察了热水抽提前后原料表面形貌变化。结果表明:烟末和烟棒的纤维特性相近,与烟梗差别较大:①烟末和烟棒的灰分、热水抽出物和综纤维素在10%,59%和27%左右,与烟梗相差较大(分别为12.30%,53.72%和27.04%);3种原料的聚戊糖和木质素含量相近,均在7%和9%左右。②3种原料经热水完全抽提后,细胞表面蜡质层消失,细胞壁明显变薄,纤维轮廓更清晰。③3种原料的纤维长度均较短,细小组分含量均较高。相比烟末和烟棒,烟梗原料的纤维质量较高,其质量平均长度为0.76 mm,细小组分含量为20.6%。④根据再造烟叶原料的纤维特性差异,在再造烟叶制浆过程中,可以用不同的打浆条件处理不同纤维特性的原料,从而获得高质量的浆料;另外,在打浆过程中需控制浆料打浆力度,避免重度打浆。 相似文献
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近年来,世界范围内造纸原料短缺的矛盾日益尖锐。人们在不断开发新的造纸原料的同时已经认识到废纸作为再生资源用于制浆造纸的重要性。但废纸纤维较差的强度性能又使它的应用受到很大的限制,如何提高再生纤维的强度性能,增强其结合力已成为目前迫切需要解决的问题。本试验通过中浓打浆对废纸纤维进行研究,希望对该资源的应用有所研益。1试验1.l试验所用脱墨废纸浆(DIP)为实验室制备。1.2打浆设备为PFI磨,试验采用15%、20%两个打浆浓度,装浆量为zvg(绝干),飞刀辊与打浆林间隙为0.Zmm,打浆压力为1.gkN/m。1.3抄片定… 相似文献
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打浆过程中纤维的润胀 总被引:1,自引:0,他引:1
打浆是利用机械的方法处理悬浮于水中的纤维,并赋予纤维某些特性。这些特性一般包括纸料的滤水性、柔软性、可塑性。使纸料通过纸机抄造能达到预期的质量指标。在打浆过程中,纤维形态发生了变化,这些变化集中反映在纤维细胞壁上。纤维的润胀和细纤维化是纤维在打浆过程中的两种主要变化,是关系到 相似文献
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水稻秸秆纤维素纳米晶须的制备及其表征 总被引:1,自引:0,他引:1
为开发水稻秸秆的高附加值应用,采用2,2,6,6-四甲基哌啶-氮-氧化物(TEMPO)体系,以水稻秸秆为原料制备纤维素纳米晶须,并采用傅里叶变换红外光谱仪、扫描电子显微镜、X射线衍射仪等对其进行表征分析。研究结果表明:水稻秸秆主要含有纤维素、半纤维素和木质素,经化学处理后纤维素含量显著提高,而半纤维素和木质素含量有所降低;水稻秸秆横截面呈多孔状,内部及表面均随机分布着大小不等的球状颗粒;化学处理部分去除了非纤维素物质,纤维表面变得相对较光滑;冷冻干燥后的纤维素纳米晶须交织成多层网状,直径为10~25nm,长度为200~400nm;水稻秸秆及其纤维与纤维素纳米晶须的结晶度分别为29.76%,30.28%和40.71%,三者均表现为纤维素Ⅰ的晶体结构。 相似文献
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CONCEPCIÓN VIDAL-VALVERDE JOSEFA HERRANZ INMACULADA BLANCO ENRIQUE ROJAS-HIDALGO 《Journal of food science》1982,47(6):1840-1845
The dietary fiber, cellulose, hemicellulose, lignin and pectic substances of 21 fruits have been determined. For some of these fruits several varieties and different degrees of ripeness have been considered. The contents of these compounds ranged between 0.2– 2.75% for dietary fiber, 0.06–1.8% for cellulose, 0.00–0.86% for hemicellulose, 0.06–0.5% for lignin and 0.12–1.28% for pectic substances. In some cases the dietary fiber can be affected by the fruit variety. Plantain increased in dietary fiber, hemicellulose and pectic substances content with increased ripening, while no change in cellulose and a decrease of lignin content were observed. 相似文献
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Heru Suryanto Eko Marsyahyo Yudy Surya Irawan Rudy Soenoko 《Journal of Natural Fibers》2014,11(4):333-351
This study was to investigate the morphology, structure, and chemical properties of the Mendong fibers extracted from Mendong grass (Fimbristylis globulosa) in the form of raw and treated fiber by alkali-included chemical content and functional group and to evaluate the strength and properties of Mendong fibers compared with other natural fibers. These studies explore the chemical properties of the fiber including fiber composition and functional group by FTIR, mechanical properties of fiber, and the structural and morphological analysis of the fiber using SEM and XRD. The results showed that the chemical contents of Mendong fibers were 72.14% cellulose, 20.2% hemicellulose, 3.44% lignin, 4.2% extractive, and moisture of 4.2%–5.2%. Mechanical properties of the fiber were a strong character with tensile strength of 452 MPa, and modulus of 17 GPa. The structural properties of Mendong fiber such as crystallinity, crystalline index, microfibril angle, and crystalline size were 70.17% and 58.6%, 22.9°, and 14.3 nm, respectively. This fiber has competitive advantages compared with other natural fibers and can be developed further as a potential reinforcement of polymer matrix composites. 相似文献
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分别采用稀酸和酸碱顺序两种方法处理稻草秸秆,20 FPU/g(底物干重)的纤维素酶、底物质量浓度为80 g/L,45℃酶解72 h。结果表明,木质素与半纤维素对纤维素转化为葡萄糖都有较大影响,稀酸处理的秸秆酶解纤维素转化率(43.4%,葡萄糖质量浓度24.1 g/L)是未处理秸秆(16.8%,葡萄糖质量浓度6.2 g/L)的2.6倍,而酸碱顺序处理的秸秆(60.6%,葡萄糖质量浓度47.7 g/L)则是未处理秸秆的3.6倍。采用上述两种方法处理秸秆后,秸秆木质素和半纤维素被移去,秸秆结构发生改变,从而秸秆纤维更易受纤维素酶的攻击,并且秸秆木质素和半纤维素质量分数越低,纤维素的酶解得率就越高。 相似文献
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探索开发废弃化学纤维、蛋白纤维、植物纤维共混与木质素、半纤维素绿色合成的新工艺、新产品;突破旧衣与秸秆纤维复合循环制造共性关键技术,为旧衣纤维资源再生绿色循环利用开辟了新的途径;同时为造纸废水中的木质素、半纤维素利用增加附加值,提升旧衣及秸秆的经济价值。 相似文献
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对稻草进行对甲苯磺酸(p-TsOH)一步法制浆和两步法制浆,并与碱法制浆进行对比,探讨了p-TsOH法制浆的可行性。结果表明,与碱法稻草浆相比,p-TsOH稻草浆的得率更高,成纸的松厚度及强度更好;p-TsOH两步法制浆可以进一步提高木质素脱除率,且浆料纤维断裂少,平均纤维长度更长。其中,稀碱-p-TsOH两步法制浆(N-P45T70t60)比p-TsOH一步法制浆(P45T70t60)的木质素脱除率高12.7个百分点,成纸的抗张指数和耐破指数分别高4.52 N·m/g和0.653 kPa·m~2/g,耐破指数与碱法稻草浆成纸相当。 相似文献
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Evaluation of pretreatment with Pleurotus ostreatus for enzymatic hydrolysis of rice straw 总被引:5,自引:0,他引:5
Taniguchi M Suzuki H Watanabe D Sakai K Hoshino K Tanaka T 《Journal of Bioscience and Bioengineering》2005,100(6):637-643
The effects of biological pretreatment of rice straw using four white-rot fungi (Phanerochaete chrysosporium, Trametes versicolor, Ceriporiopsis subvermispora, and Pleurotus ostreatus) were evaluated on the basis of quantitative and structural changes in the components of the pretreated rice straw as well as susceptibility to enzymatic hydrolysis. Of these white-rot fungi, P. ostreatus selectively degraded the lignin fraction of rice straw rather than the holocellulose component. When rice straw (water content of 60%) was pretreated with P. ostreatus for 60 d, the total weight loss and the degree of Klason lignin degraded were 25% and 41%, respectively. After the pretreatment, the residual amounts of cellulose and hemicellulose were 83% and 52% of those in untreated rice straw, respectively. By enzymatic hydrolysis with a commercial cellulase preparation for 48 h, 52% holocellulose and 44% cellulose in the pretreated rice straw were solubilized. The net sugar yields based on the amounts of holocellulose and cellulose of untreated rice straw were 33% for total soluble sugar from holocellulose and 32% for glucose from cellulose. The SEM observations showed that the increase in susceptibility of rice straw to enzymatic hydrolysis by pretreatment with P. ostreatus is caused by partial degradation of the lignin seal. When the content of Klason lignin was less than 15% of the total weight of the pretreated straw, enhanced degrees of enzymatic solubilization of holocellulose and cellulose fractions were observed as the content of Klason lignin decreased. 相似文献