As a natural material with good biocompatibility and biodegradability, nano-cellulose has unique structure and excellent mechanical properties. It has been widely used in the construction of electrochemical energy storage system of lithium-ion batteries(LIBs), and has made significant progress. This thesis provided an overview of the preparation and modification methods of cellulose nanofibrils(CNF), cellulose nanocrystals(CNC) and bacterial cellulose(BC) in the context of the application of advanced energy storage devices LIBs and green materials nanocellulose, and reviewed the research progress on the application of nanocellulose in the field of LIBs. It was mainly divided into three aspects: first, nanocellulose-based flexible LIBs electrodes; second, carbon materials derived from nano cellulose as electrodes; third, nano cellulose derived battery separator. Finally, some problems in this field were analyzed, summarized and prospected.

Hollow mesoporous silica microspheres SiO₂-1 and SiO₂-2 were prepared by sol-gel and hydrothermal synthesis using dichloride-N, N'-bis (3-hydrorosin loxy-2-hydroxypropyl) tetramethylenediamine (DHRT) as template agent and ethyl orthosilicate as silicon source.SEM, TEM, FT-IR, XRD and nitrogen adsorption-desorption were used to characterize SiO₂-1 and SiO₂-2.The results showed that silicon dioxide microspheres with amorphous structure were successfully prepared by both methods; the agglomeration phenomenon between silica particles gradually disappeared with the increase of the amount of template agent (0.1-1 g); SiO₂-1 was mainly loose microsphere with patterns, and SiO₂-2 was hollow microsphere with the wall thickness of 80-85 nm.The average particle size distributions of SiO₂-1 and SiO₂-2 prepared with different template dosages (0.3-1 g) were 0.22-0.33 μm and 0.34-0.41 μm, respectively.The morphology and particle size of SiO₂-1-0.7 and SiO₂-2-0.7 prepared by two methods exhibited good morphology and low particle size, with specific surface area of 561.52 and 463.41 m²/g, cumulative pore volume of 0.35 and 0.42 m³/g, and average pore size of 2.56 and 3.66 nm, respectively.Zeta potential analysis showed that the formation of SiO₂ hollow mesoporous structure was mainly caused by the cooperative self-assembly process between the oligomer obtained by hydrolyzing polycondensation of ethyl orthosilicate and the template agent.

In order to promote the development of biomass gasification technology and the utilization of gasification products, the development and industrial status of biomass gasification technology, gasifier type and its development status at home and abroad were mainly introduced, and the advantages and disadvantages of biomass gasification technology were analyzed. At the same time, it is also found that China's biomass resources had great potential and biomass energy had the excellent characteristics of renewability, such as renewable, less pollution, large reserves, wide distribution, zero carbon emissions and so on. However, it was difficult to internationalize because of a series of problems such as imperfect of collection-storage-transportation system, shortage of capital chain and more by-products. It was further prospected that biomass gasification in China should not only take a basic research, but also consider the overall demand of biomass gasification technology and the competition with other technologies as the future development direction and important key point. This paper was expected to lay a solid foundation for the further development of biomass gasification technology and the high-value utilization of gasification products.

Tannic acid(TA) is a kind of multi hydroxyl aromatic biomass. The thermal properties of TA were analyzed by thermogravimetric experiment, the carbonization process of TA was observed by muffle furnace heating experiment, the apparent activation energy was observed by KAS and Ozawa method, and the most probable function was determined by Satava method. Thermogravimetric analysis showed that TA entered the state of rapid weight loss at about 182 ℃; when the temperature reached 800 ℃, the carbon residue of TA in nitrogen atmosphere was 15.29%. In air atmosphere, the carbon residue was 1.97% due to the second rapid weight loss in the temperature range of 436-538 ℃. It was found in the macro carbonization experiment that TA would form an expanded carbon layer when heated. Among them, a hollow carbon layer appeared at 100-200 ℃, and a solid carbon layer was formed at 300-400 ℃, which had obvious expansion, integrity, compactness and good gloss. It had the potential to become a new carbon source in intumescent flame retardants. The results of thermal decomposition kinetics showed that the apparent activation energy of thermal decomposition of TA in nitrogen atmosphere was 494 kJ/mol, lgA was 111.32, and the most probable mechanism function of rapid weight loss stage was G(α)=[-ln(1-α)]^1/n, n=0.105 3, and its thermal decomposition mechanism belonged to random nucleation and subsequent nucleation growth reaction.

With the depletion of petroleum resources and the increasingly serious white pollution, the preparation of bio-based poly(ethylene 2, 5-furandicarboxylate)(PEF) from lignocellulosic resources has become one of the research hotspots in the fields of biorefinery and green chemical industry. Compared with petroleum-based plastics, such as poly(ethylene terephthalate)(PET) and polycarbonate(PC), PEF not only has excellent thermal properties and mechanical strength, but also has more obvious advantages in gas barrier properties, which is considered as a perfect substitute for PET. However, PEF also has some drawbacks, including low elongation at break, dark color, difficult degradation and slow deep crystallization speed. Therefore, it is necessary to modify PEF before practical application. In this paper, the research progresses of PEF modification, including copolymerization, blending and other modification methods were reviewed. The effects of different diols or diacid modified monomers, catalyst types, reaction modes, additives on the properties of PEF were summarized, and the developing trend and application prospects of modified PEF were discussed.

Supercapacitors are a new type of green energy storage device with the advantages of fast charging and discharging and long service life. The electrode material is the core component of supercapacitors. The carbon from biomass is considered as a good choice for the preparation of activated carbon because of its wide variety, low price, environmental friendly, porous structure and rich in hetero-atoms, and it is the most popular electrode material for commercial applications. This paper reviewd the effects of pore structure and specific surface area on the performance of electrochemical energy storage of activated carbon, summarized the common pore structures of biomass activated carbon such as tubular, lamellar, honeycomb and network and their electrochemical properties, and analyzed the effects of different biomass components on the performance of activated carbon from three categories: plant-based, animal-based and microbial-based. Finally, the traditional methods of preparing activated carbon and the new preparation methods in recent years were briefly introduced. The problems and challenges of biomass activated carbon were pointed out. Some suggestions were provided to guide the selection of precursors for biomass activated carbon.

Nanocellulose is a kind of nano-sized cellulose extracted from natural cellulose. It not only has the basic characteristics of cellulose, but also has large specific surface area, unique strength and optical properties originated from nano-size. However, the presence of free hydroxyl groups in cellulose is hydrophilic, which reduces the stiffness of nanocellulose materials in humid environments and limits its application fields. Therefore, hydrophobic modification of nanocellulose can expand its scope of application. This article reviewed the methods of hydrophobic modification of nanocellulose in recent years, including physical adsorption modification, esterification/acetylation modification, graft copolymerization, silane coupling agent modification, etc., and summarized the research results of the above methods, as well as the advantages and disadvantages. And the future development direction was prospected in order to provide reference for hydrophobic modification research.

Desirable pine resources are the basis for the sustainable, high value-added and fine chemical utilization of pine oleoresin. According to the chemical composition and structural characteristics of pine oleoresin, combined with the analysis of the current situation of pine oleoresin resources as well as their deep processing and utilization industries, the demand for individuation pine resources is discussed from the perspective of fine utilization. By the perspectives of production, processing, utilization and benefits, intensive high-quality pine oleoresin resources are needed, which have strong oleoresin exudation, long-lasting resinosis, good quality, and easy processability. And by the perspective of deep processing and utilization, individuation oleoresin resources are needed further, which have higher quality, more useful, more balanced or more outstanding specific components. To research and breed individuation pine resources such as pimaric-type rosin, isopimaric-type rosin, mercusic-type rosin, α-pinene-type turpentine, β-pinene-type turpentine, 3-carene-type turpentine, β-phellandrene-type turpentine and longifolene-type heavy turpentine, are scientifically important and applicably valuable for the fine chemical utilization, high value-added deep processing of rosin and turpentine. It is recommended to focus on the main oleoresin-tapping pine species such as P. massoniana, P. kesiya var. langbianensis, P. elliottii, P. elliottii×P. caribaea, P. latteri Mason, etc., and carry out more integrative and interdisciplinary researches on oleoresin chemistry, fine chemicals, genomics, metabolomics, genetic breeding, resource cultivation, and chemical engineering of forest products.

Orange oil, tangerine oil and limonene were used as target samples to study their scavenging capacities on ABTS⁺·, DPPH· and O₂^-· and total antioxidant capacity(FRAP value), as well as their antioxidant abilities in vivo and inhibitory abilities to Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa. The results showed that tangerine oil had the best scavenging capacity on ABTS⁺· and DPPH·, their IC₂₅ values were 1.481 and 24.824 g/L, respectively; limonene had the best scavenging effect on O₂^-·, and the scavenging rate was 32.86% at 0.8 g/L. The ferric ion reducing antioxidant power(FRAP) values of limonene, orange oil and tangerine oil were close to each other and weaker than those of BHA. At the mass concentration of 100 mg/L, the catalase(CAT) activities in Caenorhabditis elegans treated with tangerine oil and limonene were about 46 U/mg, which was 1.63 times of that in the untreated control group. Orange oil, tangerine oil and limonene had a relatively good inhibitory effect on S. aureus and E. coli. The inhibitory effect of tangerine oil on S. aureus was close to limonene, and the diameter of inhibition zone was about 11 mm. Orange oil, tangerine oil and limonene had an excellent antioxidant activity in vitro and in vivo, and they were moderately sensitive to S. aureus.

Based on the freeze-drying process and chemical vapor deposition technology, polyvinyl alcohol(PVA) was compounded with cellulose to enhance the mechanical compressibility and dimensional stability of cellulose(CE) aerogels, followed by the fabrication of highly elastic, hydrophobic, and porous CE/PVA composite aerogels. The effects of PVA content on the mechanical properties of CE/PVA composite aerogels were studied. As the mass fraction of PVA increased, the compressive strength of cellulose aerogels increased. When the amount of PVA was 15% of the mass of cellulose, the compressive strain increased to 66 kPa, which was increased by 6.5 times. Simultaneously, the influences of silane modification on the microstructure, thermal stability, hydrophobicity, specific surface area and physical properties of composite aerogels were explored, and the results showed that S-CE/PVA composite aerogel modified by methyltriethoxysilane(MTES) had a denser lamellar structure, the initial decomposition temperature rose to 314.6℃, the water contact angle was as high as 115°, the specific surface area was 109.42 cm³/g, the density was 0.045 g/cm³, and the porosity was greater than 95%.

A choline chloride-urea(molar ratio of 1:2) based deep eutectic solvent(DES) system was used as a non-hydrolytic pretreatment media to prepare the cellulose nanofibrils(CNF) from bleached kraft poplar pulp by using microfluidizer. The properties of CNF were characterized by elemental analysis, scanning electron microscope(SEM), Fourier transform infrared spectroscopy(FT-IR), thermogravimetric analysis and X-ray diffraction analysis. Furthermore, the polymerization degree(D_P) of CNF and the energy consumption were calculated. The results showed that DES pretreatment could promote the swelling of pulp fibers, which was beneficial to fibrillation during the microfluidization process. The microfluidization treatment, was performed 15 times. It was found that compared with the energy consumption(4.35×10⁷ kW·h/t) of raw materials without DES pretreatment, the energy consumption(2.44×10⁷ kW·h/t) of raw materials with DES pretreatment decreased by 43.91%. whereas the crystallinity indexes(I_Cr) of CNF prepared before and after pretreatment were 54% and 44%, respectively. However, DES pretreatment had no obvious effect on the polymerization degree of fiber raw materials. DES pretreatment also reduced the thermal stability of CNF. The increase of homogenization times could promote the fibrillation of fibers, and reduce the crystallinity and polymerization degree of cellulose at the same time. FT-IR analysis showed that choline cations interacted with anionic groups of cellulose fibers through static electricity during DES pretreatment. Elemental analysis showed that nitrogen-containing residues remained in CNFs.

Lignin is an amorphous, highly cross-linked polyphenol aromatic polymer with a wide range of sources and rich carbon content, and is suitable for the preparation of porous carbon materials. Using lignin to prepare porous carbon is an important way to solve the problem that lignin is difficult to be used efficiently. It can solve environmental pollution and realize resource utilization. This article mainly introduced the research status of the preparation of microporous activated carbon with lignin as carbon precursor by physical and chemical activation method and the preparation of mesoporous carbon materials by template method in recent years. The pore structure and morphology of porous carbon materials prepared by different methods were compared and analyzed, as well as their application progress in adsorption, catalysis and electrochemistry.

Furfural residue is the biomass waste in the process of furfural industrial production. In this paper, the sources and composition characteristics of furfural residue are firstly introduced. On this basis, the researches of furfural residue in the fields of biomass energy, composite materials, fine chemicals and agricultural supplies are reviewed, and the research progress in various application fields is analyzed and summarized. Finally, according to the characteristics of furfural residue, the existing problems and challenges in the application of furfural residue are pointed out and the high-value utilization of furfural residue are also prospected.

As a medical plant with a long history, the Usnea species of lichen are widely distributed in China. However, the research about its chemical composition and activity is rare, delayed, and the basic data accumulation is weak, which restricts its further development and utilization.The primary metabolites polysaccharide(lichenan, isolichenan, galactomannan, and heteropo-lysaccharide) and fatty acids, and secondary metabolites(single benzene ring derivatives, depsides, depsidones, and benzofuran) of the Usnea species of lichen are reviewed in this article.The research progress of the bioactivity of lichen polysaccharide and lichen acid are introduced. Lichen polysaccharides have functions of antioxidation and antitumor; and lichen acids have functions of insecticidal, antibacterial, anticancer, antitumor, antioxidation, antivirus, antiinflammatory, liver-protecting, detoxication, and enzyme inhibition.

In this work, the effects of sodium chlorite(SC) and sodium hydroxide(SH) pretreatments on the chemical composition of poplar were investigated. The preparation of xylooligosaccharides(XOS) and monosaccharides by enzymatic hydrolysis was discussed. The results showed that poplar lignin could be selectively removed by SC pretreatment. After 6% SC pretreatment at 70℃ for 3 h, the removal of lignin reached 65.8%, whereas 90.7% glucan and 92.4% xylan were retained. The data of X-ray diffraction and X-ray photoelectron spectroscopy indicated that SC pretreatment removed the total lignin in poplar and the surface lignin on poplar, and increased the crystallinity and accessibility of the substrate. After the pretreatment with 6% SC at 70℃ and 1% SH at 50℃, the contents of glucan, xylan, and lignin in the pretreated poplar were 67.8%, 21.5%, and 2.9%, respectively. The highest XOS yield of 47.2% from the SC-SH-pretreated poplar by xylanase hydrolysis was obtained, and the XOS preparation was composed of 98% xylobiose. Compared with the poplar treated by 6% SC at 70℃ for 3 h, SH pretreatment increased the yield of XOS by 7.1 times. After the hydrolysis by xylanase, the glucose yield of two-step pretreated poplar residue was 90.2% with a cellulase lading of 30 mg/g dry matter. Finally, 52.5 g XOS, 317.6 g glucose and 49.9 g xylose were obtained from 1 kg raw poplar. The results of this work provided a theoretical guidance for the preparation of XOS and monosaccharides from poplar under mild conditions.

Stimulus-responsive hydrogels, as a new class of functional polymer materials, can actively sense the difference of the external environment and reflect the change to the outside world by specific ways such as swelling or contraction, and show a great application potential in many fields of life and production. As a renewable natural resources, biomass has been widely applied in the preparation of stimulus-responsive hydrogels in recent years. Particularlly for rapid development of engineering technology and applications, including controllable/active polymerization and click chemistry, dynamic covalent bond, supramolecular self-assembly and super molecular aggregation state regulatory molecules, etc, is able to overcome the instrisic structure defects of biomass macromolecule to a certain extent, and fabricate the stimulus-responsive hydrogels containing unique molecular structure of biomass raw materials, which promoted the development of new green synthesis strategies, multi-functional technology, simple modular synthesis technology, modern biotechnology and other technologies. Based on the stimulus-responsive methods and types of stimulus-responsive hydrogels, this paper assembles six types of hydrogels, including temperature response, acid-base response, light response, electric response, magnetic response and multiple response and highlights the effect of the unique molecular structure of biomass raw materials on the performance of the stimulus-responsive hydrogels. Also, the applications of biomass-based hydrogels with different environmental responses in the fields of drug controlled release, biological tissue engineering, biosensors, adsorption materials, cell culture and antibacterial materials were summarized, and the future development direction of biomass-based hydrogels was prospected.

In this article, the research progress of electrochemical technology of lignin depolymerization recently, including micro electrochemical expression of lignin depolymerization, types of catalysts, electrode materials and electrode mechanism of electrochemical reactor and other strategies, were reviewed. The frontier research of lignin depolymerization by electrochemical technology combined with ionic liquid catalysis system, biological enzyme catalysis system and photocatalysis technology were analyzed. The influences of electrode material and current density on electrocatalytic efficiency were summarized, and the challenges as well as the opportunities of the application of electrochemical technology were presented.

To explore the development and utilization of flavonoids in the leaves of the main bamboo species of Bambusa, extracts of leaves from ten bamboo species were obtained by extraction, separation and purification, using bamboo leaves from Bambusa as the materials. A HPLC method was established for the determination of 5 flavonoids in extract of bamboo leaves, and the antioxidant activities of those extracts were evaluated by DPPH and ABTS assays. The HPLC method for the determination of 5 flavonoids isoorientin, orientin, vitexin, isovitexin and luteoside in extract of bamboo leaves was using YMC-Pack ODS-A column(250 mm×4.6 mm, 5 μm) with 0.5% acetic acid/water(A) and acetonitrile(B) as the mobile phases, elution with 14% B for 40 min, the injection volume 10 μL, the flow rate 1 mL/min, the column temperature 30 ℃ and the detection wavelength at 340 nm. Under these conditions, the five flavonoids were completely separated within 40 min, the degree of separation was greater than 1.2, and the concentration had a good linear correlation with the peak area(R²>0.999). The recovery rate was 94.36%-105.37%, and the relative standard deviation(RSD) was 0.98%-3.48%. These results indicated that the method was stable and reliable. The total contents of 5 flavonoids in extract of leaves from 10 bamboo species of Bambusa measured under these conditions were 62.30-223.24 mg/g, and the mass fraction of bamboo leaves extract from B. multiplex f. fernleaf was the highest(223.24 mg/g). The half inhibitory mass fraction(IC₅₀) values of DPPH· and ·ABTS⁺ were 28.58-44.37 mg/L and 8.58-11.07 mg/L, respectively, slightly higher than those of Vc and BHT. The bamboo species with better DPPH· scavenging rate were B. eutuldoides (IC₅₀=28.58 mg/L), B. textilis (IC₅₀=28.68 mg/L) and B. multiplex f. fernleaf (IC₅₀=31.65 mg/L). The bamboo species with better ABTS^·+ scavenging rate were B. multiplex f. fernleaf(IC₅₀=8.58 mg/L), B. multiplex f. silverstripe(IC₅₀=9.11 mg/L) and B. textilis (IC₅₀=9.27 mg/L). The IC₅₀ values of B. multiplex f. fernleaf and B. textilis of two kinds of radicals were lower, which were the two bamboo species with the best removal effect and the most value of development and utilization.

Firstly, this review introduced the research background and application status of bio-based hydrogels. According to the different crosslinking mechanisms, physical and chemical hydrogels were classified and described. Then, the hydrogels prepared from cellulose, chitosan, protein and other bio-based materials were summarized based on the classification of the used biomass, including the solvents system of cellulose, the preparation of cellulose-based hydrogels and modification of cellulose derivatization. Also, the feedstock sources and modification methods of chitosan-based hydrogels, as well as cross-linking mechanisms such as electrostatic interaction and imine bond formed by amine groups on their molecular chains were assembled. Protein-based hydrogels with good biocompatibility and bioactivity, formed by β-folded self-assembly of polypeptide chains were depicted as well in this review. Similarly, bio-based hydrogels prepared by using physical or chemical crosslinking of hydrophilic natural polymers such as starch, sodium alginate and carrageenan, were introduced respectively. At the same time, the main applications of functionalized bio-based hydrogels in the biomedical fields were described in detail, including drug sustained release, targeted delivery, cell media, tissue repair scaffolds, wound dressings, etc. In addition, the application and research progress of bio-based hydrogels as adsorbent materials in environmental field were reviewed, and their applications in packaging, sensing, photoelectric catalysis and other fields were also highlighted. Finally, the development opportunities and challenges of bio-based hydrogels were summarized, and the future research directions were prospected.

In order to reduce the use of fossil fuels and explore new renewable energy, bio-aviation kerosene was prepared by one-step hydrogenation of castor oil in the high-pressure micro fixed bed with Pt-La/SAPO-11 as catalyst. The effect of different reaction temperature, space velocity, hydrogen pressure and hydrogen oil ratio(hydrogen volume/castor oil volume, the same below) on the selectivity of C₈-C₁₆ hydrocarbon, C₈-C₁₆ iso-alkanes, C₈-C₁₆ aromatics and conversion ratio of triglyceride were explored. The optimal technological parameters were obtained as follows: temperature 400℃, hydrogen pressure 4 MPa, space velocity 1 h^-1, hydrogen-oil ratio 1 000. Under these conditions, the conversion rates of the product was 87.78%, the selectivity of C₈-C₁₆ hydrocarbon was 58.24%, the selectivity of C₈-C₁₆ iso-alkanes was 17.32%, and the selectivity of C₈-C₁₆ aromatics was 10.72%. According to the previous research, it was speculated that the unsaturated fatty ricinoleic acid was converted into saturated ricinoleic acid by hydrogenation on the Pt-La/SAPO-11 catalyst, and then intermediate products such as alcohols and acids were generated at the acidic sites of the catalyst. The hydrocarbon product obtained through dehydroxylation, decarboxylation and other reactions on metal sites and acid sites, and finally obtained aviation fuel component C₈-C₁₆ alkanes under hydrogenation, cracking and isomerization reactions.