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.

用羊八井加密阵列数据寻找与BASTE实验相符的3TeV能区的宇宙γ暴

采用西藏羊八井加密阵列数据 ,对美国CGRO天文卫星上的BASTE实验在 1998年 3月期间所观测到的15个宇宙γ暴进行了 3TeV能区的符合寻找。这些γ暴均位于羊八井阵列的有效观测视场内。在寻找工作中采用了组团方法 ,以提高观测阵列对γ暴的灵敏度。寻找结果表明 ,所有BASTE符合暴候选事例团的多重数分布均在背景的统计涨落之内 ,没有发现存在 3TeV能区BASTE符合暴的证据。这个结果支持了γ暴的宇宙学起源模型。

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.

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。

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.

Growth, Development and Yield of Kenaf as Affected by Planting Dates and N Fertilization

Kenaf (Hibiscus cannabinus L) consists of various beneficial components like stalks, seeds, leaves, fibers, oils, proteins, allelopathic chemicals, and fiber strands, among other things. Despite the numerous uses of the crop, there is little or no information on optimum agronomic practices such as planting date and N fertilization of the crop in the Upper East Region (UER) of Ghana where the crop is widely cultivated by smallholder farmers. Field experiments were therefore carried out in 2020 and repeated during the 2021 cropping season in the study area. The objective of the study was to determine appropriate planting date and N fertilization for increased kenaf productivity. In each year, the treatments consisted of 3 × 5 factorial combinations of three planting dates (1st July, 7th July and 14th July) and five levels of N (0, 20, 40, 60 and 80 kg/ha) replicated three times. The design of the experiment was a split-plot with the N fertilizer as the main plot and the planting date assigned to sub plot. The results showed that, planting kenaf in early (1st) July or N fertilization at the rate of 60 kg/ha increased plant density, stem height, stem diameter, dry bast and core yields in both cropping seasons.

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。

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。

Physico-mechanical characteristics of bast fibres of Sesamum indicum and Sesamum radiatum for bioprospecting

Natural fibres are renewable,inexpensive and biodegradable sources of sustainable materials from plants or animals.Bast fibres,as the notable natural fibres,are gathered from the outer cell layers of the stem of plant.Mature and young bast fibres from two species of Sesamum,namely Sesamum indicum L.and S.radiatum Schumach.&Thonn.were extracted through traditional water retting technique and analyzed for their physical,mechanical and chemical attributes.Anatomical studies revealed polygon shaped phloem(bast fibre)cells with small lumen were similar to jute,in terms of architecture,and bagasse,in terms of lumen size.Upon extraction and subsequent drying,the young stems of S.radiatum were found to yield more bast fibres by mass compared with the rest of the Sesamum samples,that was,0.59 g(dry weight)of bast fibres from 100 g(fresh weight)of stem.According to stereo microscopic images,the mature S.radiatum fibres had rougher edges than the rest.Both S.indicum and S.radiatum fibre surfaces also seemed to have pores,according to scanning electron microscopy(SEM)images.The porosity appeared to get more pronounced as the plants got older.The Sesamum bast fibres were also found to be extremely hydrophilic with a high-water retention value.The fibres obtained from S.radiatum were determined to be suitable for the textile industry due to their light colour,ideal diameter and length,and water-holding capacity that matched the requirements of fabric manufacturing.Even in the absence of a mordant,the mature fibres showed a significant degree and evenness of Alizarin dye attachment,which might be correlated to the increase in fibre surface roughness with fibre maturity.These fibres were also discovered to be comparable with jute in terms of phloem cell shape(polygonal),diameter(13-15 m),tenacity(12.86-32.54 gf/(g·km-1)),and linear density(2.5-3.3 g/km).It suggested that they might find industrial applications if further research were to be done.

棉秆皮微晶纤维素/改性氧化石墨烯阻燃纤维的制备及其性能

为提高棉秆皮微晶纤维素(MCC)纤维的阻燃性能,采用9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)为改性剂对氧化石墨烯(GO)进行改性,将改性后的GO(DOPO-GO)与MCC共混,通过湿法纺丝制得MCC/DOPO-GO阻燃纤维,并对其阻燃性能、热学性能和力学性能进行分析。结果表明:添加DOPO-GO阻燃剂的MCC纤维的极限氧指数为27.3%,较MCC纤维提高了66.5%;与MCC纤维相比,MCC/DOPO-GO阻燃纤维热分解所需的热焓值由221.8 J/g提升至1502 J/g,热学稳定性得到提高;MCC/DOPO-GO阻燃纤维燃烧后形成的残炭致密且连续,石墨化程度提高;MCC/DOPO-GO纤维的力学性能也得到了极大改善,其断裂强度由MCC纤维的0.4 cN/dtex提高至2.2 cN/dtex。

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。

Synthesis and bioassay of all four stereoisomers of (2E,4E)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one, the assignment of the absolute configuration of the sex pheromone of Matsucoccus matsumurae Japanese pine bast scale

A facile enantioselective synthesis of all four stereoisomers of (2E,4E)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one (1) is described. The stereochemistry at 6-C and 10-C of 1 was constructed by using optically active citronellal as starting material and by the asymmetric crotylic metal reaction. In the bioassay and field tests, only la, i.e. (6R,10R)-1 was active. The other three isomers 1b (6S,10R), 1c (6R,10S) and 1d (6S,10S) were inactive. Therefore, the naturally occurring pheromone was assigned as (6K,10R)-1.

黄麻韧皮纤维石油醚提取物的化学成分及抑菌分析

为充分利用黄麻资源,试验以黄麻韧皮纤维为原料,采用石油醚加热回流法提取,对提取物分别采用GC-MS法、纸片扩散法进行化学成分及抑菌分析。通过气相色谱-质谱法(GC-MS)分析鉴定出56种化合物,包括开链烃类22种、闭链烃类4种、卤代烃类5种、醇类7种、醛类1种、酚类2种、醚类2种、酮类1种、酸类3种、杂环类3种、酯类6种,其总相对含量分别为60.98%、2.65%、2.62%、22.33%、0.42%、1.35%、1.17%、0.35%、0.59%、2.70%、4.09%。采用纸片扩散法测定出提取物对金黄色葡萄球菌、大肠杆菌均能产生明显的抑制作用,对白色念珠菌抑制作用不明显。结果表明,石油醚可提取黄麻韧皮纤维中的γ-谷甾醇、白藜芦醇、羽扇豆醇、豆甾醇、25-羟基胆固醇、丙丁酚等多种有效药理活性物质,拓展了功能纤维利用价值。

棉麻混纺机织物舒适性评价

为探讨棉麻混纺机织物在夏季服装中的舒适性,以市售不同混纺比的棉麻(苎麻、亚麻、汉麻)机织物为研究对象,在实验室条件下对透气性、透湿性、导湿性和保暖性等热湿舒适性指标进行了客观测试,利用语义差分法对刺痒感、黏体感等触感舒适性指标进行了主观评价,并基于织物的结构参数对舒适性指标进行了分析与讨论,最后运用改进熵权TOPSIS法对织物的舒适性进行了综合评判。结果表明:棉麻混纺织物适合制作夏季服装,且含苎麻纤维织物的综合性能优于含汉麻和亚麻织物;透气性在舒适性综合评价中所占权重最大。认为:利用熵权TOPSIS法能够有效优选出综合性能优良的织物品种,对类似服装面料的舒适性评价及选购具有一定的指导与参考价值。