Flax retting by degumming composite enzyme produced by Bacillus licheniformis HDYM-04 and effect on fiber properties

Flax enzymatic retting with composite enzyme produced by microbes with inexpensive substrates is widely researched due to less contamination and lower cost. Bacillus licheniformis HDYM-04, isolated from a liquid sample of flax retting pool, efficiently produced degumming enzymes after 48 h of fermentation with inexpensive konjaku flour, consisted of 587.5 U/mL pectinase, 365.2 U/mL mannanase, and 140.1 U/mL xylanase. Almost half the maximum activity of three above-mentioned degumming enzymes was maintained at pH 4.0–6.0 which demonstrated its stability in pH condition of flax retting. After 120 h of retting with this composite enzyme, scanning electronic microscopy showed more significant reduction in gummy components on the fiber surface than those of water retting. The fiber strength was 182.4 ± 9.3 N, 14.3% higher than water-retted samples. The long fiber rate and fiber yield also verified higher fiber productivity. The results permitted this degumming composite enzyme an applicable potential in flax retting.     

Progress in Enzyme-Retting of Flax

Abstract

New methods for retting flax are sought to overcome problems in the current method of dew-retting of flax. Published data are reviewed and new data presented on the development and testing of a method to ret flax using pectinase-rich enzyme mixtures plus chelators based on cost and fiber yield and properties. In spray enzyme retting (SER), flax stems are crimped to physically disrupt the plant's protective barrier and then sprayed until soaked with, or briefly immersed in, an enzyme/chelator formulation. Flax is then incubated at temperatures optimal for enzyme activity, washed, and dried. Pilot scale tests, conducted with 10 kg samples of flax retted with a series of formulations, showed that this method effectively retted flax stems from a variety of sources, including fiber flax, mature fiber flax, and linseed straw. Fiber yield, strength, and fineness were significantly influenced by variations in enzyme-chelator amounts. Cellulases inpectinase mixtures appeared to preferentially attack dislocations in fibers and fiber bundles resulting in loss of fiber strength. Polygalacturonases alone effectively separated fiber from non-fiber components. The SER method proved to be an effective framework for further tests on enzyme-chelator formulations that now must be integrated with physical processing to optimize the extraction of flax fibers based on cost and fiber yield and properties.     

不同等离子体对亚麻纤维接枝改性效果的比较

亚麻是一种重要的纺织纤维，具有多项优异性能，但其染色性能存在缺陷。采用大气压介质阻挡放电对亚麻纤维进行接枝改性，可明显改进其染色性能。文章研究了不同气氛下大气压介质阻挡放电引发亚麻织物接枝丙烯酸的效果与差异。结果表明，空气、氦气的接枝共聚物结构相同，氮气则不同；空气等离子体的处理效果最好。     

The Impact of Environmental Factors and Applied Agronomy on Quantitative and Qualitative Traits of Flax Fiber

According to the Liebieg’s law—in many regions of Europe, the main limiting factor that affects very often flax yield are weather conditions (precipitation). Resistance to drought stress of 51 flax genotypes was evaluated in pot trials (2002–2012). Controlled drought stress (62.5% optimal soil humidity) caused a decrease in fiber yield by 39.7–49.3% and a substantial drop in quality. Among the tested cultivars, the ones that gave relatively promising yields in conditions of water deficit were: Sara [PL], Ilona [NL], Modran [PL], Escalina [NL], Luna [PL], Aliz?e [FR], Artemida [PL], Selena [PL], Modran [PL], Nike [PL], and Venica [CZ]. Relatively good yields of fiber for these varieties were the result of the good yields of straw.

In field trials carried out on two types of soil (pseudosolic and black soil), the highest fiber yield with good quality was obtained using: (1) sowing density of 2 800 seeds m^?2, (2) row sowing, (3) harvesting time at green-yellow maturity stage (BBCH 83). Higher plant densities using row sowing resulted in higher fiber content (% in straw) together with better quality (tex). Earlier harvest times (BBCH 75, BBCH 79) allowed for obtaining very thin fiber. The content of pectin and lignin in the fiber increased with harvesting delay.     

亚麻纤维线密度与直径回归相关模型的构建及验证

为建立一个快速有效的亚麻纤维细度的测试方法,采用传统的中段称重法获得纤维细度（Nm）,用直径显微图像仪测试出亚麻纤维直径（d）。统计软件SPSS 3.0拟合分析纤维直径和纤维细度的相关性,获得6个回归模型。优化后的回归方程为Nm=159＋2.505×105/d2,相关系数 r=0.801**,表明亚麻纤维直径和纤维细度间存在着比较好的相关性。F-检验和t-检验证明该方法与传统中段称重法差异不显著。实验室间验证结果表明该方法具有比较好的精密度、重现性和再现性。因此通过显微图像仪测试纤维直径,再经过存储在主机上回归方程的换算,同步实现亚麻纤维细度的自动化快速检测。     

Enzyme-Retted Flax Using Different Formulations and Processed Through the USDA Flax Fiber Pilot Plant

SUMMARY

Mature Ariane flax was retted with various proportions of the commercial enzyme mixture Viscozyme L (0.05, 0.1, 0.2, and 0.3% of product as supplied) and ethylenediaminetetraacetic acid (4,7, and 18 mM) from Mayoquest 200. Retted material was then cleaned through the USDA Flax Fiber Pilot Plant (Flax-PP) consisting of the following: 9-roller crushing colander, top shaker, scutching wheel, and 5-roller grooved colander. To simulate cottonization of fiber for use in textiles, the Flax-PP-cleaned fiber was passed 1 × through a Shirley Analyzer. Fiber yields and properties (strength, elongation, fineness, and color), which were determined for the various processing stages, were influenced by various formulations and by processing stage. For this flax sample, 0.05% Viscozyme plus 18 mM EDTA produced the highest yield of Flax-PP and Shirley-cleaned fibers, strong fine fibers of light color, and the strongest coarse fibers from Shirley by-product material.     

用化学方法改善亚麻可染性的研究

通过对亚麻化学改性,在亚麻大分子上引进阳离子基团,可使其在无盐的中性染浴中利用活性染料进行染色,本文研究了亚麻与N-羟甲基丙烯酰胺/胺化反应的机理,探讨了反应后亚麻染色性能的改善原理,实验结果表明,改性后亚麻在无盐条件下对活性染料的上染率、固色率达90%左右,染色牢度较好,并可大大节约染料。     

图像分析法测定亚麻纤维分裂度的研究

针对人工检测亚麻纤维分裂度的诸多缺点,提出了采用图像分析法测定亚麻纤维分裂度的方法.该方法将亚麻纤维按照外观形态进行分类,不同的类别采取不同的方法进行测定;将纤维均匀分散于黑色板面之上,通过调整光线,使用数码相机获取图像;采用Image-Pro Plus软件对图像进行分析,得到关于纤维像素的大量数据;使用自编的MATLAB程序对数据进行筛选及分析,得出纤维的准确数量,计算分裂度.试验结果表明,与人工检测方法相比,图像分析法具有操作简便、速度快、准确性高、节省人力等特点.     

Fiber Flax Breeding in China and Europe

In Western Europe fiber flax breeding was started in the Netherlands in 1816, and pedigree selection was introduced in 1900 in the Netherlands also. Therefore, the commercial breeding of fiber flax started at the end of the 19th century. Flax breeding in other European countries started in the early 20th century. Before Western European variety became available, European varieties seeds were imported from Russia. In China, breeding work on fiber flax began at 1950s. After the end of the 20th century, flax breeding technologies developed more rapidly. The flax breeding methods now include hybridization, induced mutation, interspecific hybridization, utilization of male-sterility, ploidy breeding, tissue culture, gene transformation, marker assisted selection, etc. Despite of new breeding methods, the cross breeding is still the main breeding method for fiber flax. The history of flax breeding, germplasm collection, breeding goals, breeding programs, breeding methods, and new varieties are presented in the article. Some problems about flax breeding were analyzed, and some suggestions were presented.     

亚麻/棉混纺纱的上浆工艺

目前，越来越多地使用亚麻混纺纱以改善其性能上的缺陷。麻、棉都是天然纺织材料，亚麻／棉混纺织物因其手感滑爽、透气、粗犷等独特的风格，越来越受到高档消费者的青睐。文章介绍了亚麻／棉混纺纱的上浆工艺，通过大量实验测试和分析浆液性能和浆纱质量，得出了适宜于亚麻／棉混纺纱上浆的最佳工艺配方。     

Effects of Combine Harvesting on Head Rice Yield and Chaff Content of Long and Short Grain Paddy Harvest in Sri Lanka

Paddy harvesting is the process of collecting the mature rice crop from the field which consists of activities such as cutting, handling, threshing and cleaning. Cutting, threshing and cleaning plays an important role to reduce postharvest losses. Lower performance of traditional harvesting process, labour shortage, reduced turn-around time and use of high yielding varieties have inevitably forced farmers to shift into mechanical grain harvesting in Sri Lanka. Rice milling is carried out to produce an edible polished or white rice product from harvested rough rice. Head rice yield is considered for marketing purposes because broken rice has low price in the market. Field survey was conducted in Polonnaruwa, Ampara and Hambanthota districts to identify most popular types of combine harvesters operating in the above districts. Paddy samples were collected from harvest of two most popular models of combine harvester in triplicate. Paddy sample of 1m² area from every paddy field were harvested separately by manual harvesting followed by manual threshing and cleaning in laboratory as control sample of relevant paddy field. Moisture content of the paddy grains were measured in the paddy field using digital moisture meter before harvesting. Paddy samples were subjected to sun drying until the moisture content come down to 14±1% before the quality analysis in the laboratory. Each paddy sample was analyzed for moisture content, chaff percentage and head rice yield percentage (HRY). Paddy was milled using laboratory scale rubber roll sheller and abrasive polisher. Chaff content percentage was measured by adding 100 ml of paddy to water and volume of chaff was measured using graduated cylinder. HRY was calculated dividing the weight of grain partials, which are larger than the ³/₄ of the grain, by weight of paddy sample. HRY between the two combine harvesting machine models evaluated were not significantly different at p<0.05 and also it was not significantly dependent on the harvesting methods such as combine harvesting and manual harvesting. The chaff content was significantly higher in model-2 in comparison to control sample for long grain paddy while model-1 was not significantly different with control sample for short grain paddy.     

How Does Light Intensity Affect the Elementary Fiber Length in Flax?

Abstract

There are not enough antecedents about the effect of a decrease in photosynthesis on flax stem growth and elementary fiber length. Therefore, plots sowed with cultivar Diane were shaded with nets that intercepted 70% of photosynthetically active radiation. The nets were placed at three stages of the growth period: S1: 575°Cd (height: 25 cm), S2: 854°Cd (height: 54 cm), and S3: 1304°Cd (height: 84 cm). These applications resulted in stems shadowed only in the parts, which grew during the treatment. Additionally, control plots without shadows during the entire cycle (S0) were grown. In every treatment the production of fiber was quantified, and a harvest index (HI = fiber biomass obtained/stems biomass produced) was calculated. Fiber quality was also evaluated using elementary fiber length. The harvest index was bigger in control plants than shadow plants. The length of elementary fiber of the shadow treatments S1, S2, and S3 was 4.28 cm, 3.76 cm, and 3.02 cm, respectively, whereas the adjacent portions to the shaded one in each treatment had a length fiber increase of 21%, 34%, and 37%, respectively. In the same portions, S0 had fiber lengths of 4.94, 4.45, and 3.82 cm, respectively. The trend observed in all the shaded treatments showed a decrease of elementary fiber length. The fiber length in the adjacent portions to the shaded ones was not conditioned by the shadow treatment received. These results allow relating fiber quality with stresses generated by meteorological events that take place during the growth of the stem.     

亚麻纤维混纺纱的工艺实践

为了顺利纺制CJ/Tencel/亚麻55/30/15 14.5 tex混纺纱,分析了亚麻、Tencel和棉三种纤维的性能特点,针对亚麻纤维较短且粗硬纤维较多的特点,对其进行软化处理以提高其可纺性;针对Tencel纤维易产生静电的缺点,需对其进行抗静电处理;各工序车速偏低控制,粗纱、细纱捻系数偏大控制。通过一系列的工艺技术措施,最终使整个生产过程较顺利,但成纱粗节、棉结相对偏多,需在以后的生产过程中加以控制。     

Evaluation of percentage oil yield,energy requirement and mechanical properties of selected bulk oilseeds under compression loading

The present study examined the percentage oil output, energy and mechanical properties of selected bulk oilseeds namely pumpkin, hemp, sesame, milk thistle, cumin and flax by a uniaxial compression process of a maximum load capacity of 500 kN and a preset speed of 5 mm/min. Each sample was measured at 60 mm pressing height with a plunger using the pressing vessel of diameter 60 mm. The results show that milk thistle seeds required the highest force corresponding to the highest stress and energy demand for recovering the oil in both the bulk oilseeds and seedcakes. However, pumpkin seeds produced the maximum residual oil yield of 24.99 ± 0.04%, followed by sesame seeds at 21.29 ± 1.82% and then flax seeds at 22.61 ± 0.31%. The study revealed that higher energy is required to produce the maximum oil yield with minimum residual oil in the seedcake by continuous pressing.     

The response of polymer optical fiber (POF) to bending and axial tension for the application of a POF sensor for automotive seat occupancy sensing

The automotive industry is a promising area for innovations in the field of polymer optical fiber (POF) sensors as the industry currently uses the POF mostly for data transmissions. Since an optical fiber sensor has a high bandwidth, is small in size, is lightweight, and is immune to electromagnetic interference, it offers higher performance than that of its electrical-based counterparts such as the strain gage, elastomeric bladder, and resistive sensor systems. This enhanced performance makes an optical fiber sensor a suitable material for sensing seat occupancy for improved safety features in automobiles. The overall goal of this research is to develop a textile-based optical fiber sensor for automotive seat occupancy with high accuracy and reproducibility. In this study, the bending and tensile loading responses of POF were investigated, where two perfluorinated (PF) graded index (GI) POFs with two different core/cladding diameters, 62.5/750 and 62.5/490 μm, were used. The bending loss and the light attenuation against the applied axial stress were measured by a photon counting optical time-domain reflectometer. The critical bending diameters were analyzed: Cytop-1 (62.5/750 μm)?≥?38.10 mm, Cytop-2 (62.5/490 μm)?≥?44.45 mm. Furthermore, the elastic sensitive strain regions (x), where the stress-induced loss was recoverable, of the POFs at a 76.2 mm gage length at a strain rate of 4 mm/min were determined: Cytop-1: 3% ≤ x ≤ 3.5%, Cytop-2: 3.1% ≤ x ≤ 3.3%. The Cytop-1 was found to be less sensitive to bending and to have greater elastic sensitive strain range relative to the Cytop-2. In this study, a theoretical approach of the PF GI POF behavior to bending and axial tension was provided. The results demonstrated the feasibility of POFs as optical fiber sensors for automotive seat occupancy sensing.     

一种小型辅助人力甘蔗收割装置

目前我国的甘蔗收割仍靠人工,为了减轻人工收割甘蔗的劳动强度和提高效率,本文设计了一种小型的脚带式辅助人力收割甘蔗的装置。收割人员可通过下踩装置上的踏板达到剪切甘蔗的目的,代替了弯腰收割甘蔗的动作。本文对该装置进行了虚拟分析,以solidworks建模为基础,对装置进行了力、关键部件、位移分析,进行了样机的设计验证。     

Permeability anisotropy of flax nonwoven mats in vacuum‐assisted resin transfer molding

The resin flow characteristics of natural fiber mats must be taken into consideration in the design and optimization of liquid composite molding processes. This paper studied two common types of nonwoven mat structures produced by the parallel‐laying process and the cross‐laying process. The flax fiber orientation distribution characteristics of these mats were determined by using a fast Fourier transform (FFT) image analysis algorithm. Flax fiber mats produced by the parallel‐laying method had a prominent principal direction of fiber orientation, while mats produced by the cross‐laying method had a nearly random fiber orientation. The parallel‐laid mats showed a higher overall compressibility than the cross‐laid mats because of the tendency of nesting between layers of parallel fibers, leading to a lower porosity under the same vacuum level and thus a lower overall permeability. The cross‐laid nonwoven mats demonstrated nearly isotropic in‐plane permeability, while the parallel‐laid mats showed a much higher permeability in the principal fiber direction than in the orthogonal direction.     

The Dimensional Distribution of Kenaf and Apocynum Fibers

ABSTRACT

In this research, single fiber cell separation method was studied and optimized. More than 200 fiber cell dimensional sizes of kenaf and apocynum were analyzed. Furthermore, the diameter changes of kenaf fiber cell before and after different degumming treatments were also explored. Results showed that the average length and diameter of kenaf fiber are 2.16 mm and 10.56 μm, while the average length and diameter of apocynum fiber are 9.04 mm and 7.41 μm. It was also found that the average diameter of kenaf and apocynum fibers decreased with the degumming process, and the diameter distribution became more even.     

亚麻增强聚丙烯复合材料薄板的冲击性能

以亚麻纤维为增强体,与聚丙烯(PP)树脂长丝进行丝束级混合,形成PP包覆亚麻的纱线结构,利用机织工艺织成二维机织布,作为复合材料的预制件。采用层合热压的方法制备亚麻/PP复合材料薄板。通过对板材冲击性能的测试以及破坏形貌的分析,研究了亚麻/PP薄板的冲击破坏机制以及影响板材冲击性能的因素。结果表明:斜纹组织板材的冲击性能优于相同制备工艺的平纹组织板材;树脂、纤维、铺层数、冲击速度等因素对板材的冲击性能均有影响。     

亚麻与天然蛋白质纤维混纺纱的开发

阐述了市场对亚麻混纺纱的开发需求,以及在棉、毛混合设备上纺制亚麻混纺纱存在的问题。亚麻纺织品凉爽,透气性好,吸湿、散湿快,挺括不贴身,强力好,且有一定的保键功能,是理想的夏季服装面料。亚麻是天然纤维中惟一的束状纤维,无天然卷曲,刚直,弹性差,抱合力差,可纺性差,较脆,易断裂,在纺纱过程中应合理选用原料和选择纺纱方法。经过多次试验,合理地制定出了各工序的主要工艺参数。