Table of Content

30 November 2023, Volume 57 Issue 6 Previous Issue   

Research Report

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Preparation and Sodium Storage Properties of Bamboo Hard Carbon Gaoyue ZHANG, Ao WANG, Hao YING, Wei XU, Hao SUN, Kang SUN, Jianchun JIANG 2023, 57 (6):  1-7.  doi: 10.3969/j.issn.1673-5854.2023.06.001 Abstract ( 14 )   HTML ( 5 )   PDF (2262KB) ( 22 )   Save Bamboo-based hard carbon materials for sodium ion battery anodes were prepared by a two-step method of pre-carbonization combined with high-temperature reforming using bamboo as raw material. The influence of reforming temperature on the structure of hard carbon, and the structure-activity relationship between structure and sodium storage performance were explored. The research results showed that the high refining temperature could shrink the pores to form a closed pore structure and reduce the specific surface area, as well as led to a decrease in the layer spacing. When the refining temperature was 1 400 ℃, the specific surface area of the sample BHC-1400 was 9.2 m2/g, and the layer spacing was 0.375 nm. Its rich closed-pore structure and reasonable interlayer spacing were beneficial to the improvement of sodium storage capacity. BHC-1400 exhibited a reversible sodium storage capacity up to 364.3 mAh/g at a current density of 50 mA/g and an initial Coulomb efficiency of 81.2% as an anode material for sodium-ion batteries. Capacity retention rate keeps at 85% after 5 000 cycles of charging and discharging. Figures and Tables | References | Related Articles | Metrics

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Ultrasound Assisted Preparation and Characterization of Corn Cob Lignin Oligomers Jingyi LIU, Lin MA, Chunpeng WANG, Fuxiang CHU, Yuzhi XU 2023, 57 (6):  8-14.  doi: 10.3969/j.issn.1673-5854.2023.06.002 Abstract ( 11 )   HTML ( 3 )   PDF (5263KB) ( 14 )   Save Lignin oligomers were prepared by ultrasonic-assisted depolymerization using corn cob lignin as raw material. The effects of depolymerization conditions on the yield and relative molecular mass of lignin oligomers were investigated, and the lignin oligomers were characterized by gel permeation chromatography(GPC), infrared spectroscopy(FT-IR), two-dimensional nuclear magnetic resonance spectroscopy (2D-HSQC NMR) and nuclear magnetic resonance phosphorus spectroscopy (31P NMR). The results showed that the yield of resultant lignin oligomer reached 40.2% and the number-average molecular weight (Mn) of obtained lignin oligomer was 710 under the conditions of ultrasonic treatment (frequency 40 kHz, power 240 W) for 3 h and the solid-liquid ratio of lignin to solvent 200:1(g: L) in methanol/water (4:1, v: v) solvent system. The polydispersity index (PDI) was 1.62, which reserved the main molecular structure units of lignin, and the total hydroxyl content was 10.49 mmol/g. Figures and Tables | References | Related Articles | Metrics

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Green Separation of Lignocellulose and Properties of Reconstituted Composites Rongsheng SHEN, Dengfeng WANG, Yangliu CHEN, Lin LIU 2023, 57 (6):  15-24.  doi: 10.3969/j.issn.1673-5854.2023.06.003 Abstract ( 8 )   HTML ( 1 )   PDF (3551KB) ( 13 )   Save In order to realize the high-value utilization of waste lignocellulose, bamboo powder was used as raw material, and the deep eutectic solvent (DES) composed of choline chloride (ChCl)/lactic acid (LA) was used to separate the components of bamboo powder. The lignin and cellulose were reconstructed by a simple hot-pressing method to prepare lignocellulosic board. In this paper, the effects of the components of DES, the amount of ferric chloride, reaction temperature and reaction time on the separation of lignocellulosic components were investigated. The structure and properties of DES-separated lignin (DESL) and cellulose (DESC), DES/FeCl3-separated lignin (DESL-FeCl3) and cellulose (DESC-FeCl3), and lignin fiberboards were analyzed by infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), scanning electron microscope (SEM), Zeta potential tester, and universal testing machine. The results showed that the optimum process conditions were choline chloride and lactic acid with a molar ratio of 1:2, FeCl3 addition amount of 2%, reaction temperature of 140 ℃, and reaction time of 6 h. The yields of lignin and cellulose under these conditions were 85.57% and 48.4%, respectively. The phenolic hydroxyl number and Zeta potential of the extracted lignin were 12.86 mmol/L and -32.26 mV, respectively, and the particle size was small. The extracted cellulose had more active sites, which were favorable for the molecular reconstruction and interfacial bonding with lignin. After five cycles of recycling, DES still had good separation performance for lignocellulose. The water stability and mechanical properties of the prepared lignocellulosic board had been improved, water contact angle reached to 58.6°, and its tensile strength increased from 8.4 MPa to 53.1 MPa, which had the potential to replace petroleum-based plastics. Figures and Tables | References | Related Articles | Metrics

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Water Solubility and Antibacterial Properties of 7-Hydroxycoumarin Acylated Modified Chitosan Changwei WU, Jiayu LIU, Xiao QIU, Wenwen LYU, Ruihan JING, Dawei ZHANG 2023, 57 (6):  25-31.  doi: 10.3969/j.issn.1673-5854.2023.06.004 Abstract ( 9 )   HTML ( 1 )   PDF (3635KB) ( 10 )   Save Chitosan (CS) was modified by amidation with 7-hydroxycoumarin to improve its water solubility and enhance the bacteriostatic property by reducing the hydrogen bonding between chitosan molecules. 7-Hydroxycoumarin was firstly acylated by oxalyl chloride as a linker, and then coumarin was grafted onto chitosan molecules through a non-homogeneous amidation reaction to produce 7-hydroxycoumarin acylation-modified chitosan (CS-C). The coumarin-modified chitosan products were characterized by infrared spectrometry (FT-IR), X-ray diffraction (XRD) instrument, and thermal gravimetry, etc., for the solubility, antibacterial activity, crystalline, and thermal stability. The results showed that the chitosan had been amidated by coumarin, and the modified groups were mainly in the NH2 and chloride as well as ester bonds. The highest degree of substitution of NH2 was found when the mass ratio of chitosan to coumarin was 1:3, and the solubility mass fraction of the CS-C-3 prepared in this case could reach 79% in a neutral environment. Its bacteriostatic property was better than that of CS, with a minimum inhibitory concentration (MIC) of 0.5 g/L for Escherichia coli and a MIC of 1 g/L for Staphylococcus aureus. A minimum bactericidal concentration (MBC) value of 4 g/L for E. coli and a MBC value of 2 g/L for S. aureus. Figures and Tables | References | Related Articles | Metrics

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Effects of Different Drying Methods on the Glycosidase Activity and Effective Components of Baphicacanthus cusia Danyang LIU, Hao ZHOU, Yangyang YAN, Xiaoran YANG, Shibin SHANG, Chengzhang WANG 2023, 57 (6):  32-36.  doi: 10.3969/j.issn.1673-5854.2023.06.005 Abstract ( 6 )   HTML ( 1 )   PDF (2553KB) ( 10 )   Save Taking Guizhou Baphicacanthus cusia as the research object, the effects of 9 drying methods, including shade drying, sun drying, vacuum drying, 50 ℃ oven drying, 100 ℃ oven drying, freeze drying, hot air gun drying, microwave drying and microwave post drying, on leaf properties, effective components and β-glucosidase activity were investigated. The results showed that the dry leaves treated by microwave drying still retained green stretch state, uniform color and better appearance. The mass fractions of indigo and indirubin in the leaves of Baphicacanthus cusia dried in the oven at 50 ℃ were 0.68% and 0.051%, respectively, and β-glucosidase had higher activity (12.23 U/mg). The microwave dried Baphicacanthus cusia leaves had the advantages of good appearance and high mass fraction of indicant (8.84%), where β-glucosidase was almost completely inactivated. Therefore, the microwave drying technology could be popularized and applied in the drying process in the production of Baphicacanthus cusia. Figures and Tables | References | Related Articles | Metrics

Review Comment

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Research Progress on Bio-based Vitrimer Materials Shanyuan TONG, Yun HU, Jinni YU, Puyou JIA, Qin HUANG, Yonghong ZHOU 2023, 57 (6):  37-46.  doi: 10.3969/j.issn.1673-5854.2023.06.006 Abstract ( 20 )   HTML ( 1 )   PDF (748KB) ( 25 )   Save Traditional polymer materials were divided into thermoplastic materials and thermoset materials. Thermoplastic materials could be processed twice but not rigid enough, and thermoset materials were rigid but difficult to recycle. The glass-like polymer material was between thermoplastic material and thermosetting material, which was a kind of material with high crosslinking density network and could be processed twice. Based on the network exchange mechanism of Vitrimer, this paper focused on the development history and research progress of bio-based glass polymers. Bio-vitrimers based on different covalent bonds were introduced in detail. Generally, the conditions of dynamic transesterification reaction were relatively mild, the reaction speed was fast, and the reaction materials were extensive, while the mechanical properties and reversibility of materials were poor. The reversibility and controllability of dynamic disulfide bond exchange were better, and the reaction was not harsh to the external acid-base environment, while the reaction substrate generally had toxic behavior and pungent odor. Dynamic imine bond exchange could make the material had good mechanical properties and durability, and good biocompatibility, while the reaction conditions and raw material selection were relatively simple. The application and advantages of bio-based Vitrimer materials were reviewed. The introduction of dynamic covalent bonds made up for the shortcomings of traditional 3D printing materials, such as insufficient rigidity and single function, enhanced the comprehensive performance of carbon fiber composites, and improved the service life and self-healing efficiency of elastomer materials. Finally, the paper gived a prospect of the future development. Figures and Tables | References | Related Articles | Metrics

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A Review on Recent Advances in Biomass Liquefaction in Water Mixed Solvent Systems Yan MA, Hongxiao WANG, Guodong FENG, Ziyang WU, Weihong TAN 2023, 57 (6):  47-55.  doi: 10.3969/j.issn.1673-5854.2023.06.007 Abstract ( 15 )   HTML ( 4 )   PDF (663KB) ( 16 )   Save Solvent liquefaction was an effective process which could utilize biomass raw materials efficiently and comprehensively. Compared with water as a single solvent, the mixed solvent system could reduce the reaction temperature and pressure, improve the conversion of biomass, reduce the oxygen content in bio-oil, and increase the yield of the target product. This paper reviewed the common water mixed solvent systems in recent years, including the role of alcohol-water cosolvent, polar aprotic solvent-water system and ionic liquid-water system in the degradation process of lignocellulosic biomass, especially the application characteristics of ethanol-water cosolvent, tetrahydrofuran (THF)-water cosolvent and γ-valerolactone (GVL)-water cosolvent in biomass liquefaction. This paper also gave the shortage and suggestions of these solvents in biomass liquefaction field. Finally, based on the consideration of the economic value, recovery and safety performance of the solvent itself, it is pointed out that the development of low-cost, environment-friendly and sustainable liquefying solvents would be the key development direction in the future. Figures and Tables | References | Related Articles | Metrics

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Research Progress on the Role of Plant Polyphenols in Aquaculture Manqi YANG, Liangliang ZHANG, Liming LU, Yiwen LIU, Jianchun JIANG 2023, 57 (6):  56-66.  doi: 10.3969/j.issn.1673-5854.2023.06.008 Abstract ( 12 )   HTML ( 16 )   PDF (751KB) ( 14 )   Save With the rapid development of aquaculture towards scale, the healthy problems of aquatic animals caused by the abuse of antibiotics had become increasingly prominent. Therefore, the development of green and efficient alternatives to antibiotics had emerged. Plant polyphenols had become one of the excellent alternatives of antibiotics, because of their effects of promoting growth, antioxidant, antibacterial, anti-inflammatory and promoting intestinal health, as well as no side effects and drug residues. According to the results of relevant studies, plant polyphenols in appropriate dosage had a positive effect on the growth and physiological status of aquatic animals. This article summarized research advances on the effects of plant polyphenols on the growth performance, antioxidant capacity, anti-inflammatory, antibacterial and intestinal health of aquatic animals. Figures and Tables | References | Related Articles | Metrics