Isolation and Characterization of Cellulose Nanofiber(CNF)from Kenaf(Hibiscus cannabinus)Bast through the Chemo-Mechanical Process

The present work emphasizes the isolation of cellulose nanofiber(CNF)from the kenaf(Hibiscus cannabinus)bast through a chemo-mechanical process.In order to develop high CNF yield with superior properties of CNF for improving compatibility in varied applications this method is proposed.The fiber purification involved pulping and bleaching treatments,whereas mechanical treatment was performed by grinding and high-pressure treatments.The kraft pulping as a delignification method followed by bleaching has successfully removed almost 99%lignin in the fiber with high pulp yield and delignification selectivity.The morphology of the fibers was characterized by scanning electron microscopy,which showed a smooth surface,fiber bundles,gel-shaped nanofiber,and an average size of 94.05 nm with 69%of CNF in 34–100 nm size.The chemo-mechanical process exhibited a more crystalline nature in CNF than pulp kenaf.The low zeta potential values exhibit the distribution of fibrils and colloidal suspension stability without any further agglomeration.A lower concentration of CNF is less stable exhibiting the product agglomeration.Therefore,the chemo-mechanical process for the isolation of CNF(Hibiscus cannabinus)from kenaf involves sustainable,low-cost,non-toxic,and cheap alternatives than other traditional methods.

Effects of Bast Fiber Seedling Film on Quality and Root Respiration Enzyme Activities of Seedlings of Different Rice Varieties

This study was conducted to investigate the effects of bast fiber seedling film on rice seedling growth. In this study, indica cultivar ＇Xiangwanxian 13＇ and indica hybrid cuitivar ＇Y Liangyou 1＇ were used to investigate the changes of aboveground part growth and root respiration enzyme activities of rice seedlings af- ter the application of bast fiber seedling film. The results showed that, compared with the CK, the accumulation of shoot biomass, chlorophyll content, root bleeding intensity, soluble sugar content, and nitrate nitrogen content were significantly im- proved with the application of bast fiber seedling film. In addition, the activities of malate dehydrogenas （MDH） and alcohol dehydrogenas （ADH） were higher in rice seedling roots raised with bast fiber seedling film, while there was no significant change in lactate dehydrogenase （LDH） after the application of bast fiber seedling film. However, there were no significant differences in these indexes between the two cultivars. All the results indicated that the growth and development of rice seedlings could be improved with the application of bast fiber seedling film.

Isolation and Characterization of Cellulose Whiskers from Kenaf (<i>Hibiscus cannabinus</i>L.) Bast Fibers

Cellulose whiskers were isolated from kenaf (Hibiscus cannabinus L.) bast fibers via sulfuric acid and hydrochloric acid hydrolysis. Raw kenaf bast, NaOH treated, bleached fibers, sulfuric acid whiskers (SAW) and hydrochloric acid whiskers (HClW) morphology, functional groups, crystallinity, and thermal stability were characterized. The TEM images showed that the sulfuric acid and HCl whiskers have average diameters and length range of 3 nm and 100 - 500 nm, respectively. The FTIR study indicated that during the conversion process, most of the hemicellulose and almost all the lignin were removed by the NaOH and subsequent bleaching treatments. The crystallinity of HCl whiskers was found to be higher (84%) than that of sulfuric acid whiskers (72%). Thermogravimetric analysis indicated that HCl whiskers had better thermal stability than the sulfuric acid ones. In addition, a two-stage decomposition behavior was revealed by TGA in the sulfuric acid whiskers because of incorporation of the sulfate group with the cellulose crystals.

Bast Fiber Starts to Shine

Bast fiber, which has not attracted that much attention before, is going to step up to be more recognized, so there comes the bast fiber fashion week, as an appetizer for the bast fiber promotion year.

Properties and Processing of the Pineapple Leaf Fiber

The properties and constituent of pineapple fiber were tested, and on the base of that, chemical treatment was used to improve the spinnability of the fiber, and the pure and blended yarn of pineapple fiber were produced in worsted and cotton spinning system.

A Comparison of the Tensile Strengths of Yucca Fiber Extracted by Microbial and Chemical Methods

Leaves from greenhouse-grown Yucca plants were harvested and retted by microbial and chemical methods respectively.The dimensions and tensile strengths of the two sets of products were compared.While the fibers obtained by microbial retting had superior tensile strength,the chemically retted fibers were devoid of debris,whiter and generally more attractive.The method of retting should match the use to which the plant fibers are intended.

Identification of 13th-14th Century Chinese Handmade Paper Fibers Collected in Yuan Dynasty Paper Currencies

The earliest paper currencies in existence in China were handcrafted during the Yuan dynasty.These currencies were scientifically excavated from different ruins or tombs,whereas scientific analyses of the papers are rare.This study used optical and scanning electron microscopy to examine the fibers collected in Yuan dynasty paper currencies in conjunction with the Herzberg staining method.Despite differences in circulation period,paper fibers in both Zhi Yuan Tong Xing Bao Chao(two Guan)and Zhong Tong Yuan Bao Jiao Chao(one Guan and 500 Wen,issued in Zhi Zheng period)were identified as similar papermaking materials,bast fibers of mulberry bark.The results indicate that mulberry bark,a durable papermaking material used since ancient times,was mainly utilized as a raw material in these Yuan dynasty paper currency.This fiber identification work solved the critical problem of papermaking material in the Yuan dynasty paper currency and provided important information for conserving these precious cultural relics.

新时期我国麻类产业科技创新的重点任务

麻类作物是重要的特色经济作物,为高端纺织、食品医药、生物材料等领域提供重要工业原料,持续加强麻类产业科技创新对我国农业农村现代化建设具有重要意义。针对新时期麻类产业发展承担的新职能,文章梳理了近年来我国麻类产业技术研发重要进展,分析了麻类产业发展面临的新挑战,并结合新兴技术研发态势,提出了我国麻类产业科技创新的重点任务。研究建议:新时期我国麻类产业科技创新应进一步夯实种质资源研究,推进现代生物育种技术应用;加快抗逆丰产技术创新,在盐旱渍涝污染等边际土地中拓展种植空间;研发全产业链绿色低碳技术,促进麻类生产高产高质高效;创新加强麻类新材料创制,带动麻类产业创新发展,赋能粮食安全与重要农产品有效供给。

黄麻韧皮纤维活性物质鉴定及抑菌效果分析

采用溶剂法从黄麻韧皮纤维中提取黄酮、多糖、生物碱3种成分,并对提取物的化学组分及抑菌效果进行测定分析。结果表明,3种提取物中总黄酮、总多糖、总生物碱含量分别为17.36 mg/g、3.57 mg/g、61.01μg/g。高效液相色谱法(HPLC)检测出黄酮类提取物主要包括异槲皮素(167.47μg/g)、槲皮素(12.35μg/g)、木犀草素(6.41μg/g)、山奈酚(6.26μg/g)等;多糖类提取物中的单糖组分有半乳糖(0.41 mg/g)、半乳糖醛酸(0.43 mg/g)、阿拉伯糖(1.03 mg/g)等;生物碱类提取物主要组分为盐酸小檗碱(9.97μg/g)。纸片扩散法、二倍稀释观察法、扫描电镜分析显示,3种提取物对金黄色葡萄球菌、大肠杆菌、痢疾杆菌均能产生不同程度的抑制效果。综上,黄麻韧皮纤维中的活性物质较为丰富,且具有良好的抑菌性能。

麻类作物活性成分的抗炎作用研究进展

在国内,麻类作物是一种被广泛种植的经济作物,除纺织、食品、建筑材料等常见用途,其活性功能成分在生物医药、农业等领域亦有广泛研究和应用;文章综述了常见麻类作物(如亚麻、大麻、苎麻等)活性成分的抗炎效果与机理,及其在医药与畜牧领域的研究、应用现状,展望了其作为新抗炎药物的潜力,旨在为今后麻类作物活性成分在大健康领域的深度开发提供科学参考.

两种麻纤维育秧膜对水稻秧苗根际土壤微生物群落结构的影响

试验主要探究了壳寡糖麻育秧膜和普通麻育秧膜对水稻秧苗根际土壤理化性质和微生物群落结构的影响。结果表明:使用两种不同麻育秧膜组中土壤pH、总氮含量增加;普通麻育秧膜处理下土壤有机质显著降低;壳寡糖麻育秧膜处理下总钾含量显著降低。与无膜覆盖的对照组相比,两种不同麻育秧膜处理下水稻秧苗根际土壤真菌多样性并没有显著变化,而细菌的多样性和丰富度显著降低。对根际土壤理化性质和土壤微生物群落进行冗余分析,发现水解氮与根际土壤真菌群落的相关性最大,而土壤有机质则与根际土壤细菌群落分布的相关性最大。

可降解地膜对大棚内土壤温湿度和草莓产量及品质的影响初探

冬季大棚草莓种植常用地膜覆盖,塑料残膜危害严重,试验以塑料地膜为对照,研究两种PBAT地膜(PBAT地膜1、PBAT地膜2)和一种环保型麻地膜对大棚内土壤温湿度和草莓产量及品质的影响,验证可降解地膜在草莓种植中应用的可行性。结果表明:PBAT地膜1草莓苗穴处温湿度较高,麻地膜膜下湿度最低;可降解地膜早期开花率和结果率高于塑料地膜;PBAT地膜1和麻地膜栽培的草莓早期产量显著高于塑料地膜,分别高出33.37%和22.98%,草莓总产量各处理间无显著差异;结果盛期各处理的草莓甜度和硬度无显著差异,塑料地膜、PBAT地膜1和麻地膜草莓单果重更高。试验初步表明,PBAT地膜和麻地膜可以用于冬季大棚草莓种植,其中PBAT地膜1和麻地膜效果最优。

不同采收期罗布麻纤维的变化及脱胶工艺

研究了不同采收期罗布麻韧皮的化学组分和纤维性能,以及罗布麻KOH脱胶工艺。研究发现,随着采收期从7月延长到11月,罗布麻韧皮中纤维素质量分数由31.9%上升至46.8%,木质素含量也呈递增趋势,半纤维素、脂蜡质、果胶、水溶物含量呈递减趋势,脱胶后纤维细度、单纤维强力以及单纤维长度均增加。10月后采收的罗布麻纺织服用性能更好。罗布麻KOH脱胶条件为KOH 10 g/L,H_(2)O_(2)4 g/L,时间75 min,浴比1∶50,脱胶后纤维白度83.6%,残胶率4.50%,单纤维断裂强力21.69cN,纤维素质量分数87.9%。SEM观察表明,脱胶后纤维表面光滑。

无纺结构麻纤维复合材料疲劳性能及失效机理

近年来,以可持续性为特征的麻纤维因其在环境可接受性和商业可行性方面的优势而备受关注。以麻纤维代表之一的洋麻毡为增强材料,不饱和聚酯(UP)为基体,采用手工叠层和模压成型的方法制备了洋麻/UP复合材料。设计低周疲劳(低速低循环疲劳)和高周疲劳(高速多循环疲劳测试)来探讨其疲劳性能和疲劳极限,重点观察不同疲劳测试条件下麻纤维的断裂形态和失效机理。

A Comprehensive Analysis of the Thermo-Chemical Properties of Sudanese Biomass for Sustainable Applications

The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing.

生物酶改善澜沧荛花皮的造纸性能研究

本研究用果胶酶、半纤维素酶、果胶酯酶及由以上几种酶组成的复合酶,预处理澜沧荛花皮,以还原糖含量来评价生物酶对非纤维物质的脱除效果,并测试纸浆的得率、卡伯值、纸张物理性能等指标以评价不同生物酶对澜沧荛花皮造纸性能的影响。结果表明,由果胶酶(10 mL)、半纤维素酶(10 mg)、果胶酯酶(10 mL)复配的D_(1)酶对非纤维物质脱除效果最优,D_(1)酶预处理液中还原糖溶出量为7.4%。D_(1)酶预处理后蒸煮所得浆料的卡伯值与对照样A_(0)(未经酶预处理)相比下降了5.3%,纸张白度增加了10.3%。D_(1)酶预处理20天与未经酶预处理的原料分别在K_(2)CO_(3)用量为5%和6%(以Na_(2)O计)的条件下蒸煮,纸张耐折度提高了30.3%、抗张指数提高了14.8%、撕裂指数提高了11.2%,表明生物酶预处理能够减少蒸煮过程中化学品的用量,并提升纸张的物理性能。

荛花韧皮部制浆工艺优化及纸浆性能研究

以荛花韧皮部为研究对象,分析了韧皮部的化学组分含量,初步对比了五种不同制浆方法对纸浆性能的影响,从而选择出荛花韧皮部合适的制浆方法,并优化其制浆工艺。实验结果表明,荛花韧皮部硝酸乙醇纤维素含量为54.6%,木素含量为8.7%,果胶含量为18.1%,苯醇抽出物为2.6%;与其他四种制浆方法相比,AS-AQ制浆方法在制浆得率及纸浆卡伯值、特性黏度、白度等方面较有优势,因此荛花韧皮部采用AS-AQ法制浆较为合适,其最佳的制浆工艺条件为:用碱量14%,亚硫酸化度80%,升温时间1.5 h,保温时间3 h,最高温度140℃,液比1:5;在此工艺条件下浆料得率为60.1%,卡伯值为9.66,特性黏度为1115 mL/g,白度为44.74%ISO。

X射线衍射法分析棉秆皮纤维结晶结构

棉秆皮纤维是从棉秆皮中提取的新型纤维素纤维。利用X射线衍射分析仪测试棉秆皮纤维,根据X射线衍射图的分峰结果计算棉秆皮纤维的结晶度、结晶指数和晶粒尺寸等结晶结构参数。

麻地膜降解对土壤性质和作物产量影响的研究

为了研究麻地膜在土壤中的降解特性以及麻地膜降解后对土壤物理、化学及生物学特性和作物产量的影响,分别在春、夏、冬3个季节条件下观测RC麻地膜、JC麻地膜和塑料地膜在土壤中的降解特性;JC麻地膜分别设2层(JC2)、4层(JC4)、8层(JC8)、12层(JC12)、16层(JC16)、塑料地膜4层(P4)、8层(P8)、12层(P12)共9个处理,另设未使用地膜作对照(CK),用盆栽试验方法研究了麻地膜在土壤中的降解及对土壤性质和作物产量的影响。结果表明,麻地膜在土壤中能充分降解,温度升高可加速其降解;麻地膜降解可降低土壤容重和增加孔隙度,改善土壤三相比例,增加土壤养分,提高土壤微生物数量,培肥土壤。麻地膜埋入明显促进红麻根系生长,改善根冠比,提高了植株的养分积累量;红麻的日生长量、株高、茎粗、皮厚以及干物质量均高于对照,红麻干皮产量均明显高于CK,并且有随着麻地膜埋入量的增加而提高之势。塑料地膜的埋入则恶化了土壤生态环境,影响了红麻生长发育而造成减产。因此,麻地膜的埋入能够改善土壤生态环境,同时促进作物生长发育及产量的提高。