Sindora glabra Merr.ex de Wit has being increasingly appealed to be utilized for its oil as fuel since 1980,but recommendations on how to start were rare.In this paper, the history of classification and utilization of this plant was described and the existing problems on its utilization as fuel resource were pointed out.The authors concluded that the present available knowledge on S.glabra was not enough for its utilization.Priorities should be put on resource inventory, cultivation, breeding, mechanism of oil producing, harvest technology, combustion property study and construction of information net.

The polymers based on dynamic borate bonds had certain self-healing ability and multiple responses to stimuli, and they could respond to biological signal changes by inducing topological recombination of physical/chemical structures in the materials. A variety of natural/non-natural polymer materials based on three different transesterification mechanisms of borate esters were reviewed in this paper, namely hydrolysis/re-esterification, transesterification between diol and borate and transesterification between borate and borate. It was a strategy to design a more stable tetrahedral borate structure through the synergistic effect of traditional covalent bond and borate dynamic covalent bond to solve the borate ester polymer short plate. Application potential of borate-based polymers in many fields was summarized, such as biomedicine, sensors and recyclable materials. The synergistic of borate ester bond and other dynamic bonds to prepare ideal polymer materials was mainly emphasized, such as hydrogels, organic gels, liquid crystal materials, recyclable nanomaterials, etc.

In this paper, the main source and application of CO ₂,the common methods of industrial separation and recovery of CO ₂ were introduced. The application of activated carbons in separating gas used PSA technology, and the common methods of adsorbents regeneration in process of PSA were also discussed. Factors including pore structure and surface chemical structure of activated carbons that influenced the performance of adsorption and recovery of CO ₂ on activated carbons were reviewed.

The new low-energy consumption process of corn fuel ethanol developed by our team adopted low temperature liquefaction, synchronous saccharification and batch fermentation of concentrated mash, three-tower differential pressure distillation and molecular sieve dehydration process and waste heat recovery technology from various sections of the plant. At present, it has successfully applied to a number of fuel ethanol distillery. Taking the Heilongjiang Hongzhan Science and Technology Co., Ltd. 300 000-ton fuel ethanol project as an example, the technical characteristics, energy consumption and product quality were compared and analyzed between the new and the traditional process. The results showed that the steam consumption, process water and amount of circulating water of the new process were reduced by 10.26%, 28.09% and 11.11% compared with those of traditional process, respectively. The production of 1 ton fuel ethanol could save 49 kg standard coal; thus 14 700 tons of standard coal could be saved annually and the energy consumption cost of fuel ethanol could be saved by about 8 million Yuan. At the same time, the product qualities of fuel ethanol and corn distiller's grains (DDGS) were in line with the national standards, some indicators were higher than the national standards, such as the purity of ethanol could reach 99.9%, methanol content was as low as 0.01%, crude protein content was 26.1%, crude fat content was 10.5% and the crude fiber content was 8.7%.

The biochars I, R, S and M were prepared at 300, 500 and 700℃ with the grasses of king grass, rice straw, bagasse and corn straw as raw materials, respectively. The effects of different pyrolysis temperatures on the structure and composition of biochar were studied. Results showed that with pyrolysis temperature increasing, the yield of the four kinds of biochars decreased, carbon content and ash content increased. The yields of I, R, S and M at 300℃ were 45.81%, 48.67%, 46.81% and 46.00%, and the yields at 700℃ were 33.95%, 35.47%, 25.42% and 31.23%. The ash contents and I, R, S and M at 700℃ increased by 54.39%, 65.44%, 95.54% and 71.85% compared those at 300℃. The C/N ratio of R, S, and M were increased with pyrolysis temperature increasing, but that of R was opposite. The pH values of the four biochars increased with pyrolysis temperature increasing. The pH values of I, R, S and M at 700℃ were 7.68, 9.87, 7.59 and 9.33. I and S was porosity and the number of pore increased with the increase of pyrolysis temperature. Both R and M formed a certain amount of flocs at 700℃. EDX analysis revealed that the elemental composition of Si was contained higher in R. Infrared spectroscopy showed that with the increase of pyrolysis temperature, the alkane groups, methyl groups (—CH₃) and methylene groups (—CH₃) of the four kinds of biochars gradually disappear. The biochar structure was dominated by aromatic compounds and oxygen functional groups, and the structure was more stable.

As a kind of polymer material with versatile product forms, polyurethane is widely used in many applications. Developing technologies that can use green and renewable raw materials as feedstock has become a research hotspot, as well as great significance to the polyurethane research in the future. Based on the relevant literatures of the last decade, this paper focuses on the basic methods and research progress for the synthesis of bio-based polyols and isocyanates from common renewable alternatives, such as vegetable oil(castor oil, soybean oil, tung oil, palm oil, etc.), lignocellulose, rosin, natural phenols(cardanol and tannin), sugars and other biomass resources. In addition, the research status of non-isocyanates was mentioned, and the unique advantages of these materials for the preparation of bio-polyurethane were listed. This article also comprehensively examines the future hurdles that hinder the utilization of these materials, and then the development prospects of bio-based polyurethane materials in different fields are outlooked.

Biomass is important renewable resources, mainly containing cellulose, hemicellulose, and lignin. Hemicellulose is the second most abundant component in plant cell walls, and it can be hydrolyzed to prepare important chemicals and modified to prepare multifunctional materials. This article reviews the research progress of molecular simulation of biomass hemicellulose, including the molecular simulation study of the morphology of hemicellulose macromolecules and its binding mode to cellulose, and the molecular simulation research on the preparation of chemicals and materials from hemicellulose. It can be concluded that the interaction of hemicellulose with cellulose and lignin in the cell wall and its macromolecular morphology have significant influence on the extraction and utilization of cellulose, hemicellulose, and lignin. Molecular simulation is helpful to understand the process mechanism and has important theoretical guiding significance for the improvement of reaction efficiency. Finally, the development and application of molecular simulation in hemicellulose research are prospected. The blank areas of hemicellulose molecular simulation are pointed out, mainly including the production of bio-oil by hemicellulose liquefaction, xylose isomerization to produce xylulose, the binding interaction between hemicellulose and lignin, and other hemicellulose-based materials, which requires further exploration and research.

In order to achieve the reduction and recycling, anaerobic digestion of sludge is the most widely used treatment method in the world. Volatile fatty acids(VFAs), an important product in acidification stage, could be used to remove nitrogen and phosphorous from wastewater as carbon sources, and to synthesize valuable products, such as bioplastics polyhydroxyalkanoates(PHAs). Metabolic mechanism and microbial mechanism of acidogenesis process during sludge anaerobic fermentation were introduced. The research results of anaerobic fermentation of sludge in recent years were reviewed systematically. The effects of substrate species, pretreatment technology, pH value and fermentative temperature on the acid production by anaerobic fermentation of sludge and its research progress were discussed. Temperature and pH value obtained more attention and it was summarized and compared the acid production by sludge fermentation under different substrate types, temperature, acid and alkaline conditions could affect the production and type distribution, while sludge pretreatment technology tended to increase the production of acid, but had little effect on the type distribution. The application of anaerobic fermentation in the synthesis of PHAs, bioenergy, nitrogen and phosphorus removal from sewage was also introduced. Finally, due to the different organic compoments of the substrate, the acidification efficiency would be different. Meanwhile, controlling the substrate type, pH value and temperature would not only affect the acid production, but also affect the acid production type. Therefore, the research directions of further study were given as the reasons for differences in acidification efficiency of different substrates, directional fermentation of sludge to produce acid, and achieving the regulation of various acids proportions in total VFAs.

In order to study the effect of the multiphase reaction flow field on the gasification process in downdraft fixed-bed gasifier, based on Fluent software, Euler Langrange model was established to track the movement of straw particles. P1 model was used to simulate the radiation heat transfer process of gasification process. At the same time, the gasification characteristics of straw downdraft gasifier were analyzed by coupling chemical reactions.The results showed that when the fuel coefficient was 0.26 and the particle size of straw was 13 mm, the volatiles of straw begin to react with the gastifier at the distance of 4.85 m from the bottom outlet of the burner. The flame temperature at the center of the gasifier increased, and then decreased with the depletion of volatiles. When the particle size of straw particles increased from 10 mm to 30 mm, the flammable gas content gradually decreased, but the content gap was not large.When the particle size of straw reached 40 mm, the temperature in gasifier dropped rapidly, then the serious phenomenon of incomplete dry volatilization would happen.

Biomass had negative carbon properties and met the requirements of green development as a typical renewable energy. Under relatively mild conditions, hydrothermal carbonization was the process of converting biomass into various functional carbon materials. This paper discussed recent advances of biomass-based porous carbon materials by the hydrothermal transformation from biomass, such as monosaccharides(glucose, fructose, and xylose), lignocellulosic fibers(cellulose, hemicellulose, and lignin) and chitosan. The effects of temperature, reaction time and raw material concentration on its structure and properties were mainly discussed, as well as its applications in gas adsorption, dye adsorption and heavy metal ion adsorption. The authors proposed future research directions for the hydrothermal synthesis of high performance and environmentally friendly porous carbon materials from biomass.

The conventional natural encapsulating materials and preparation methods for microcapsules were introduced. The natural shell materials include three typical series, i.e., carbohydrates, proteins and lipids. The traditional natural shell materials include sodium alginate, chitosan, glutin, etc., but the noval materials consist of liposome, microbial cell wall (yeast cell wall), porous starch, etc.. The common preparation methods for microcapsules include complex coacervation, simple coacervation, interfacial polymerization, in-situ polymerization, piercing-solidifying, spray drying, etc.. The advanced preparation methods for microcapsules include molecular inclusion, microchannel emulsification, rapid expansion of supercritical solution, yeast microencapsulation, layer-by-layer self-assembly, vesicle templating, etc..

As a "green technology", the light curing technology which is not only energy-saving, environmental protection but also economical and efficient, has been applied in many fields. The use of natural renewable resources to produce photocurable resins is of great significance to the sustainable development of photocurable technology. As a kind of natural renewable resource, itaconic acid with unsaturated double bond and two carboxyl groups could replace acrylic acid, hexanedioic acid and other petrochemical resources to synthesize various UV light curable unsaturated resins. The synthetic properties of the resin were excellent. The progress of preparation of itaconic acid UV light curable resins was reviewed, including epoxy itaconic acid resin, itaconic acid polyester, itaconic acid polyester acrylate, itaconic acid polyurethane acrylate, etc. The UV light curable resins from itaconic acid would have important application value in the fields of coatings, biomedicine and 3D printing, which could provide a new approach for the high value utilization of biomass products.

Environment protection, energy saving, and high efficiency are the main research directions for thermal insulation materials in the future, and the development of thermal insulation materials based on biomass is the future trend. Biomass-based porous materials refer to the porous materials prepared from renewable biomass as the precursor, which have the wide raw materials and diverse preparation methods. They have excellent characteristics, such as high porosity, low density, light weight, and so on, which has great application potential in the field of thermal insulation. In this paper, the heat preservation mechanism of the porous materials was overviewed, and the research progress on the cellulose, starch, chitosan, plant protein porous material in recent years was reviewed. The surfactant foaming method, freeze-drying method, pore-forming agent method, mould hot pressing method, solvent exchange phase separation in the application of biomass-based porous material preparation were also highlighted. Finally, the existing problems of biomass-based porous insulation materials are analyzed, and the future research directions of porous insulation materials are also prospected.

The holocellulose film was manufactured from the holocellulose that was extracted from the bagasse with using ZnCl₂ solution as solvent by using the phase inversion method. Then, the effect of holocellulose dosage(calculated by the mass of ZnCl₂ solution, similarly hereinafter), dissolution time, gelation time and glycerin soaked mass fraction on the porosity, water flux of wet membrane and mechanical properties of dry film, were investigated. Sequentially, SEM, XRD, FT-IR and TG were applied to study the dissolution and film formation mechanism. The results showed that the holocellulose extracted from the bagasse could be used as raw material to prepare cellulose films. And when the holocellulose dosage was 5%, the gelation time was 3 d and the dissolution time was 1 h, the water flux of the obtained wet membrane reached the minimum of 17.2 L/(m·h), and the porosity was 83.3%. And the corresponding dry film obtained by plasticizing with 10% glycerol had the maximun tensile strength of 21.9 MPa and the elongation at break reached 22.2%.FT-IR and TG analysis showed that hemicellulose was not contained in the film made from holocellulose, and the hemicellulose may be hydrolyzed during dissolution or precipitated during film formation. SEM image showed that there are a large number of uniform holes inside the wet membrane, and the pores of the membrane shrank to form a dense structure.XRD results showed that the cellulose type Ⅰ to cellulose type Ⅱ after film formation, and the crystallinity decreased from 48.8% to 41.5%.

Lignin is a kind of abundant, cheap and sustainable natural biomass resource. Recently, converting lignin to functional nanomaterials has greatly broadened its application. Meanwhile, this conversion greatly solved the typical problems for traditional materials. Here, in this paper, several preparation methods including preparation of lignin functional nanoparticles such as self-assembly, mechanical method, polymerization assembly, freeze-drying carbonization, etc were introduced. And then their different applications in catalysts, additives, adsorbents, UV protection and anti-oxidation, sterilization, carrier materials, aggregation-inducing emmision materials, etc were described. Also, an outlook about the prospect of its application was presented. Developing controllable preparation and functional modification will facilitate the further application of lignin-based nanoparticles in the fields of environmental protection, energy, catalysis and biomedicine.

Microcrystalline cellulose(MCC) was extracted from pineapple leaf fibrous by means of pre-acid immersion, alkaline extraction and acid hydrolysis and the influences of mass fraction of sulfuric acid solution, temperature and reaction time on the reaction were discussed. The results showed that the optimum preparation conditions of MCC were mass fraction of sulfuric acid 64%, reaction temperature 45 ℃ and reaction time 90 min. Hexagonal boron nitride(h-BN) was used to modified MCC in order to gain h-BN-MCC composite powder. The products were mainly characterized by Fourier transform infrared spectroscopy(FT-IR), scanning electron microscopy(SEM) and thermogravimetic analysis(TG). The results showed that the infrared spectrogram characteristic peaks were consistent with the reference and the mass loss of cellulose microcrystalline was 97% when the temperature raised to 700 ℃. The whisker lengths were about several to twenty microns and the diameters were 2-3 μm.Then the composite powder was dispersed in polyvinyl alcohol(PVA) to prepare h-BN-MCC-PVA composite membrane. Tensile strength and contact angle test were used to characterize the membrane. MCC could assist h-BN to compound with PVA well and tensile strength and elongation at break of h-BN-MCC-PVA composite membrane could be increased by 15.1% and 122.0% respectively. And the composite powder could enhance the hydrophobicity of the film and the contact angle could increase from 34.91° to 52.28°.

Corn straw was used as raw material for aerobic biological pretreatment by a complex bacterial system and then inoculated with anaerobic sludge for anaerobic fermentation. The influence of pretreatment time on anaerobic fermentation was investigated, and the changes in lignocellulose structure and content, key enzyme activities, microbial diversity and anaerobic acidification fermentation yield were determined. The results showed that with the extension of pretreatment time, the structure of corn straw was gradually destroyed, the activity of lignin peroxidase, the key enzyme for lignin degradation, gradually decreased, and the activities of xylanase and cellulase gradually increased and were up to 0.879 U/mg and 0.0257 U/mg. Actinomyces, Bacillus and Aspergillus were the dominant bacterium groups in the aerobic biological pretreatment of straw. The best acid production from anaerobic fermentation of corn straw was achieved by aerobic biological pretreatment for 2 d. The yield of ethanol and volatile fatty acids was 249.3 mg/g, 46.73% higher than that of untreated. The yield of ethanol and volatile fatty acids was 138.2 mg/g after 5 d of aerobic pretreatment, which was 18.66% lower than that of the untreated corn straw. The reason for the decrease of volatile fatty acids production from anaerobic fermentation due to extended aerobic pretreatment time was the excessive degradation of hemicellulose and cellulose. The pretreatment method of anaerobic fermentation of corn straw using aerobic biological pretreatment with complex microbial system as the purpose of energy and resource utilization should strictly control the pretreatment time to avoid the decrease of product yield caused by excessive degradation of cellulose and hemicellulose.

This work focused with the assistance of the mechanism of pyrolysis carbonization of cellulose, lignin and hemicellulose were analysed by TG, TEM, Raman, XRD, and FT-IR based on the molecular restructuring behavior of three major components of cellulose, lignin and hemicellulose during pyrolysis. The results showed that hemicellulose was completely decomposed during pyrolysis; molecular rearrangement occurred during the pyrolysis of cellulose, forming crystallized areas in biomass char; lignin had a very complex cross-linked structure, melted during pyrolysis, forming amorphous carbon areas in biomass char. During the charring process, cellulose undergone mainly dehydration reactions when the temperature was lower than 200 ℃, and the temperature range of 200 to 400 ℃ was the main stage of pyrolysis; lignin was relatively structurally stable in the studied temperature range(200-500 ℃), with only partial structural transformation occurring while softening and melting.

Polyvinyl alcohol(PVA) hydrogels with anisotropic microstructures were firstly prepared by directional freezing-thawing(DFT) of PVA aqueous solution, and then they were crosslinked with ⁶⁰Co γ-rays irradiation to improve their thermal stability and mechanical properties. Scanning electron microscopy(SEM) showed that original anisotropic microstructures of PVA hydrogels could be maintained after radiation-induced crosslinking. Long aligned channels were found along the parallel direction, pores with similar sizes were found along the perpendicular direction. The thermal stability tests showed that the PVA hydrogels prepared with one directional freezing-thawing cycle and irradiated with 30-70 kGy ⁶⁰Co γ-rays could maintain their original gel states in 60℃ water for more than 10 h. Tensile mechanical testing showed that the radiation crosslinked PVA hydrogels(DFT-RC-3-10) maintained their anisotropic tensile properties, moreover, the tensile strengths and elastic moduli of the radiation crosslinked PVA hydrogels(DFT-RC-3-10) were enhanced, for the PVA gel samples prepared with three directional freezing-thawing cycles and irradiated with 10 kGy ⁶⁰Co γ-ray, the tensile strength and elastic modulus in the direction perpendicular to the freezing direction were enhanced to 0.86 and 0.10 MPa, respectively.

As a new type of nano-porous carbon-based materials, carbon aerogel has many unique characteristics such as high porosity, large specific surface area, high electrical conductivity, and high thermal stability, etc., which is widely used in the fields of catalyst, capacitors and adsorption materials.Compared with traditional carbon aerogels, biomass-based carbon aerogels have the advantage in abundant and renewable precursors, which opens an opportunity for the high-value and functionalized utilization of biomass. Based on a brief introduction of the preparation process of biomass-based carbon aerogels (including sol gelation, drying and carbonization), this review paper mainly introduced the preparation methods of three types of carbon aerogels from different biomass precursors (plant cellulose, bacterial cellulose and plants with three-dimensional porous structure), and the applications of carbon aerogels in catalyst, adsorption materials, ultracapacitors and lithium-ion batteries were elaborated as well. Finally, the research direction and development prospective of biomass derived carbon aerogels were discussed.

Chitosan(CS)/polyvinyl alcohol(PVA)/chitosan oligosaccharide(CHOS) nanofibrous membrane was prepared by electrospinning. The morphology, structure, bacteriostasis, hydrophilicity and solubility of the membrane were studied. Scanning electron microscope(SEM) observation showed that CS/PVA/CHOS nanofibrous membrane had uniform and dense micro morphology. FT-IR test showed that CHOS was dispersed in CS/PVA/CHOS nanofibrous membrane in the form of physical mixing. XRD test showed that the addition of CHOS changed the crystallinity of the nanofibrous membrane and promoted the compatibility between components. Water contact angle test showed that the nanofibrous membrane had good hydrophilicity. As the mass ratio of CS, PVA and CHOS was 20:80:10, the water contact angle of CS/PVA/CHOS nanofibrous membrane decreased from 59.8° to 37.5° compared with that of CS/PVA nanofibrous membrane with the mass ratio of CS and PVA 20:80. Bacteriostatic test and solubility test showed that CS/PVA/CHOS nanofibrous membrane with mass ratio of CS, PVA and CHOS 20:80:10 were better than those of CS/PVA nanofibrous membrane without CHOS, the bacteriostasis and solubility increased 38.9% and 38.6%, respectively.

Alkali lignin(AL) was separated and purified from papermaking black liquor by acidic precipitation. Then, quaternary ammonium lignin(QAL) was obtained by modifying AL with 3-chloro-2-hydroxypropyl trimethyl ammonium chloride. Using cellulose hydrogel(CEH) as matrix, antibacterial silver nanoparticles-quaternary ammonium lignin-cellulose hydrogel(Ag NPs-QAL-CEH) was prepared by impregnating with QAL and silver nitrate solutions. The structures of AL and QAL were characterized by Fourier transform infrared spectroscopy and the results showed that QAL was successfully prepared. The results of elemental analysis showed that the content of nitrogen increased from 0.6% to 5.9%. Ag NPs-QAL-CEH was characterized by X-ray diffraction and scanning electron microscopy. The results indicated that Ag NPs were obtained by reducing Ag⁺ with QAL, and Ag NPs-QAL was uniformly dispersed in the three-dimensional network structure of CEH. The antibacterial performance of the hydrogel showed that Ag NPs-QAL-CEH formed obvious inhibition zone against S. aureus and E. coli. Furthermore, with the increase of AgNO₃ dosage, the diameters of antibacterial circle increased from 14.2 mm to 20.1 mm and 16.1 mm to 18.1 mm, respectively. When the mass concentration of AgNO₃ was 7.87 g/L in 50 mL QAL solution(including 2.5 g QAL), the obtained Ag NPS-6-QAL-CEH had the best bacteriostatic effect, and the inhibitory rates against S. aureus and E. coli could reach more than 99.5%.

The progress of experimental and theoretical work on bamboo leaves extracts was reviewed. Recently,some effective components were found in extracts of bamboo leaves,including flavonoids,polysaccharides,mineral elements and other components. The technology of extraction and purification of effective components from bamboo leaves were introduced. The biological activities of bamboo leaves extracts including antibacterial properties, antioxidant function and pesticidal function were highlighted. Some tentative conclusions are made about future short-term trends.

The experiments of biomass pyrolysis were carried out in the pipe-type furnace. The effect of pyrolysis temperature on the char yield was investigated. The difference of biomass pyrolysis char yield between agricultural biomass and forest biomass was studied. The SEM analysis of biomass char was done, the characterization of char surface structure in different pyrolysis temperature was studied. The results showed that the yield of char decreased with the increment of temperature. The char yield of cantleye corniculata and rice husk decreased from 28.38% and 45.84% at 300℃ to 7.55% and 15.45% at 600℃. The yield of char from agricultural biomass was higher than forest biomass at the same pyrolysis conditions. The maximum char yield was 30.32% from bran at 400℃. The minimum char yield was 19.23% from pyinkado, SEM analysis indicated that the char was porous structure.

Using activated carbon prepared by sawdust and PEG2000 as surface coated agent, water-soluble carbon quantum dots were synthesized by chemical oxidation method. The method of synthesis of CQDs was optimized. The optimed synthesis condition of CQDs was 0.3 g of standast activated carbon, the mixed oxidant of 40 mL HAc-80 mL 30% H ₂O ₂, at the temperature of 100 ℃ for 12 h. In order to repair the surface defect of CQDs, a passivation treatment is perfermed using ultrasonic and micromave methods. The structures and optical properties of the obtained CQDs were characterized by transmission electron microscope (TEM), Ultraviolet-Visible (UV-Vis) spectroscopy, photoluminescence (PL) spectroscopy and Fourier transform infrared spectrophotometer (FT-IR). The prepared CQDs feature the excellent optical performance and high dispersion without agglomeration. The effects of ambient temperature, light and pH value on the property of CQDs were studied. Experimental results show that CQDs have lots of advantages, such as good stability, excellent anti-light bleaching, pH value dependence and feasible surface functionalization.

Based on the cryogenic nitrogen gas adsorption method, the pore characteristics of biochars made from farmland waste including rice straw, corn stalk and wheat straw were studied. The BET equation, BJH equation and t-plot method were used to caculate the specific surface area, pore size distribution and microporous parameters, and FHH model was used to obtain the fractal dimension(D) of pore. Results showed that different temperature and different materials all had larger effects on the pore characteristics of biochar. With the increase of pyrolysis temperature, the BET specific surface area and pore volume of rice-straw-biochar and wheat-straw-biochar increased firstly and then decreased, whereas, the porosity of corn-stalk-biochar always increased. It was concluded that the mesopores were the main type of pores in three kinds of biochars and the pores mainly consisted of the second pores. It was found that rice-straw-biochar, corn-stalk-biochar and wheat-straw-biochar all had good fractal characteristics, and the pore fractal dimensions were 2.545 4-2.669 3, 2.629 7-2.689 5 and 2.577 3-2.597 2, respectively, which reflected the complexity and heterogeneity of the biochar porosity. Both rice-straw-biochar and wheat-straw-biochar had higher fractal dimension at 500 ℃(2.669 3 and 2.597 2), but corn-stalk-biochar had higher fractal dimension at 700 ℃(2.689 5).

Lignocellulose is the most abundant renewable biomass resource on the earth and cellulose is one of the three components of lignocellulose and is important raw material for the production of bio-based materials, fuels and chemicals. However, the complex chemical structure of lignin limits the application of lignocellulose. Conventional physical, chemical and physical-chemical lignin degradation methods often require high temperature and high pressure conditions, resulting in high energy consumption, inhibitors and environmental pollution. The biocatalysis process mediated by microorganisms is usually carried out under mild conditions, which can reduce energy input and provide a more specific and effective choice for the utilization of lignin. The degradation of lignin by fungi, represented by white-rot fungi, presents the problems of long pretreatment cycle and poor adaptability to the environment. Bacterium becomes the future potential of lignin degradation, owing to its rapid proliferation, profound environmental adaptability and easy genetic manipulation. This review introduced the progress of microbial degradation of lignin on the base of chemical structure, and mainly analyzed the microorganisms (fungi and bacteria), degrading enzymes (peroxidase and laccase) as well as the degradation mechanism. Besides, the applications of microbial degraded lignin in lipids, bioplastics, vanillin and wastewater treatment were summarized and the future development was suggested.

The effects of anhydrous calcium chloride on the physicochemical properties of cotton straw based porous biochar were studied with cotton straw as raw material under different temperature. The morphology and structure were characterized by simultaneous thermal analysis(TG-DSC), X-ray diffraction(XRD), Raman spectroscopy(Raman), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and N₂ adsorption-desorption analysis. The TG results showed when the pyrolysis temperature reached 500 ℃, the weight loss of the samples was less, so 550-750 ℃ was selected as the pyrolysis temperature range. The experimental results showed that the samples prepared by the two pyrolysis methods(direct pyrolysis and CaCl₂ activation) were amorphous carbon structure. During 550-750 ℃, for direct pyrolysis, the I_D/I_G values of Roman analysis were about 0.93, the maximum specific surface area was 2.09 m²/g and the average pore size was 7.21 nm; for CaCl₂ activation, the I_D/I_G values were about 0.85, the maximum specific surface area was 487.68 m²/g and the average pore size was 5.97 nm. And the samples prepared by the activation method are better than the samples prepared by the direct pyrolysis method in the degree of graphitization, specific surface area and pore size, while the samples prepared by the direct pyrolysis method had larger pore size, high degree of disorder and good stability.

Biobased epoxy resin(DGEBDB) was created using 6-(bis(4-hydroxy-3-methoxyphenyl) methyl) dibenzo [c, e] oxyphosphate 6-oxide(BDB) and epichlorohydrin(ECH) as raw materials and tetrabutylammonium bromide(TBAB) as catalyst. Then, it was solidified with bisphenol A(DHABA), a curing agent containing β-amino alcohol structure, to obtain a bio-based flame retardant and antibacterial epoxy resin(EB/DHABA) with both intrinsic antibacterial and intrinsic flame retardant properties. The relationship between structure and performance was investigated by varying the ratio of DGEBDB to commercial epoxy resin E51. The structure of DGEBDB was characterized by nuclear magnetic resonance spectroscopy(¹H NMR). The curing behavior, thermal, mechanical, antibacterial and flame retardant properties of epoxy resin were tested and analyzed by FT-IR, TG, paint film impactor, colony counter and vertical combustion tester. The results showed that EB/DHABA had been successfully prepared, the resin had excellent comprehensive properties, and the glass transition temperature could reach 130.62℃. When the content of DGEBDB in the system was 10%, the crosslinking density of the system was highest, which was 3 519 mol/m³. T_10% was about 350℃, and it decreased with the increase of DGEBDB addition. The pencil hardness of the paint film could reach up to 5H and it had good impact strength and solvent resistance. It also had good killing effect on E. coli and S. aureus, with a sterilization rate of 99.4%. The results of vertical combustion test revealed that when the content of DGEBDB in the system reached 30%, the flame retardant effect was the best, and UL-94 grade could reach V-0 grade.