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
SAT(Satisfiability)可满足性问题研究具有很广的应用价值,是计算机和人工智能领域内的一个重要问题,也是第一个被证明为NP完全的问题。随着对SAT问题的深入研究,已经提出了很多高效的算法,其中随机算法(WalkSAT)、进化算法等启发式算...SAT(Satisfiability)可满足性问题研究具有很广的应用价值,是计算机和人工智能领域内的一个重要问题,也是第一个被证明为NP完全的问题。随着对SAT问题的深入研究,已经提出了很多高效的算法,其中随机算法(WalkSAT)、进化算法等启发式算法是今年来研究的热点。进化算法是遗传算法的一种,通过对生物组织进化的学习,形成的一种高效算法。针对CNF(Con-jecture Normal Formula)权重和生物进化算法相结合,提出一种有效求解难SAT问题的不完全算法WOSAT.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National Natural Science Fundation of China(21006073)Shanghai Rising-Star Program(11QA1407200)+1 种基金open-project program of the State Key Laboratory of Chemical Engineering(SKL-ChE-08C07)Shanghai Leading Academic Discipline Project(B303)~~
文摘利用催化气相化学沉积(Catalytic chemical vapor deposition,CCVD)法在炭纸上原位生长得到CNF/CP复合体,并对这种复合体的物理化学性能和氧气电催化还原反应(Oxygen reduction reaction,ORR)性能进行了研究。结果表明:纳米炭纤维较为均匀地分散在炭纸上,其中纳米炭纤维具有窄的直径分布。所制CNF/CP复合体具有较大的比表面积和独特的中孔结构;相对于炭纸,CNF/CP复合体的端面碳原子和基面碳原子比例较高。另外,CNF/CP还具有较高的ORR反应活性,其ORR为2电子反应过程,原因可以归结于纳米炭纤维独特的微结构。同时,CNF/CP也具有较高的交换电流密度和较正的平衡电压。
文摘SAT(Satisfiability)可满足性问题研究具有很广的应用价值,是计算机和人工智能领域内的一个重要问题,也是第一个被证明为NP完全的问题。随着对SAT问题的深入研究,已经提出了很多高效的算法,其中随机算法(WalkSAT)、进化算法等启发式算法是今年来研究的热点。进化算法是遗传算法的一种,通过对生物组织进化的学习,形成的一种高效算法。针对CNF(Con-jecture Normal Formula)权重和生物进化算法相结合,提出一种有效求解难SAT问题的不完全算法WOSAT.
