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 im...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.展开更多
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 inve...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.展开更多
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 hydr...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.展开更多
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.
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...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.展开更多
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...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.展开更多
基金Ministry of Education,Culture,Research and Technology(KEMENDIKBUDRISTEK)Republic of Indonesia,for providing the Research Grant“Basic Research Scheme”No.110/E5/PG.02.00.PL/2023.
文摘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.
基金Supported by Scientific and Technological Innovation Project of Chinese Academy of Agricultural Sciences(ASTIP-IBFC07)Production Post of Degradable Bast Fiber Mulching Film of National Agro-Industry Technology Research System for Bast and Leaf Fiber Crops(CARS-19-E23)~~
文摘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.
文摘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.
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China.
文摘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.
