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28 August 2022, Volume 42 Issue 4 Previous Issue    Next Issue

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Preparation, Characterization and Electrochemical Performance of N, P Co-doped Cattail-derived Carbon Aerogels Ju HUANG, Jiaming SUN, Kun ZHANG, Zhenwei WU, Wei LI, Shouxin LIU 2022, 42 (4):  1-8.  doi: 10.3969/j.issn.0253-2417.2022.04.001 Abstract ( 311 )   HTML ( 7854 )   PDF (5060KB) ( 519 )   Save N and P co-doped carbon aerogels(NPCA) were prepared from cattail inflorescence with NH4H2PO4 as dopant by pretreatment with acidic sodium chlorite, ultrasonic cell fragmentation, freeze-drying and carbonization at high temperature. The surface morphology, pore structure, crystalline structure and surface chemical composition of NPCA were characterized by SEM, N2 adsorption/desorption, XRD and XPS. The effects of doping amounts and carbonization temperatures on the electrochemical properties of NPCA were systematically studied. The results of research showed that NPCA was a three-dimensional network structure that composed of amorphous carbon. The nitrogen element on the surface of NPCA existed in the form of pyridine nitrogen(N-6), pyrrole nitrogen(N-5), graphitization nitrogen(N-Q) and oxidation state of nitrogen(N-X), and the phosphorus element existed in the form of P—O and P—C. The pore structure and surface chemical structure of NPCA were greatly affected by doping amount of NH4H2PO4 and carbonization temperature. The optimum preparation conditions of NPAC were that the mass ratio of cattail-based cellulose to ammonium dihydrogen phosphate was 1∶2 and the carbonization temperature was 800 ℃. The NPAC-2-800 prepared under this condition has rich pore structure and surface functional groups. Furthermore, the specific surface area was 599.88 m2/g, the total pore volume was 0.27 cm3/g, the micropore volume was 0.20 cm3/g, and the average pore size was 3.69 nm, the N and P contents of NPCA were 5.69% and 5.12%, respectively. The electrochemical properties of the NPCA were measured by three electrode system in 6 mol/L KOH solution. The specific capacitance of NPCA-2-800 was 249 F/g at a current density of 1 A/g, which was 133.4% higher than that of the undoped sample(106.7 F/g), and had good rate performance. Figures and Tables | References | Related Articles | Metrics

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Preparation and Properties of Waterborne UV Curable Epoxy Itaconate Resin Modified by Polysiloxane Junna BIAN, Jian CHEN, Zhaozhe YANG, Guomin WU, Zhenwu KONG 2022, 42 (4):  9-15.  doi: 10.3969/j.issn.0253-2417.2022.04.002 Abstract ( 265 )   HTML ( 343 )   PDF (646KB) ( 432 )   Save Semi-terminated isocyanate epoxy itaconate resin modified by silicone(IPDIHSiIE) was synthesized by graft copolymerization of polysiloxane modified epoxy itaconate resin(SiIE) that was prepared from the reaction between hydroterminated polysiloxane modified epoxy itaconic acid ester resin and half-terminated isocyanate. The chemical structure of IPDIHSiIE was characterized by FT-IR and 1H NMR. Effects of the amount of polysiloxane on the physical and chemical properties of the modified resin and the film were investigated. The results showed that the reaction between polysiloxane and epoxy itaconate resin was completed at 90 ℃ for 8 h, indicating that the target product could be successfully prepared by silicohydride addition. With the increase of the amount of polysiloxane, the particle size of the modified resin dispersion gradually increased, the storage stability became worse, and the gel first risen and then fell. When the content of polysiloxane was 5%, the Z-mean particle size of aqueous dispersion was 129.8 nm, the aqueous dispersion was translucent and had no obvious change after storage for one month. Meanwhile, the gel rate reached the maximum of 93.1%. The hydrophobic property of the modified film was improved with the increase of polysiloxane content, and the film had good thermal stability. With the increase of polysiloxane content, the pencil hardness and flexibility of the film were improved, the adhesion decreased slightly and the glass transition temperature decreased gradually. Figures and Tables | References | Related Articles | Metrics

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Fractionation of Bamboo Residues by Acid Hydrotrope Guangliu XU, Zhichen ZHAO, Rui ZHANG, Han ZHANG, Junjun ZHU 2022, 42 (4):  16-24.  doi: 10.3969/j.issn.0253-2417.2022.04.003 Abstract ( 255 )   HTML ( 89 )   PDF (6312KB) ( 435 )   Save The effects of acid hydrotrope(p-toluenesulfonic acid(p-TsOH)) on the fractionation of bamboo residues, and the preparation of monosaccharides, lignin nanoparticles and furfural were investigated. The physicochemical structure variations of bamboo residues before and after the pretreatment were analyzed using scanning electron microscopy(SEM), X-ray diffraction(XRD) and infrared spectroscopy(FT-IR), and the lignin nanoparticles were analyzed by transmission electron microscopy(TEM). Under the conditions of p-TsOH mass fraction of 55%, temperature of 90 ℃ and pretreatment time of 120 min, the results showed that the removal rates of xylan and lignin were 82.72% and 82.16% respectively, while the retention rate of cellulose was as high as 87.3%.The glucose yield was 96.4% after 72 h enzymatic hydrolysis. After pretreatment, the spent liquor was diluted by slowly adding water to precipitate the lignin nanoparticles(with an average particle size of 69.33 nm). The liquid after lignin precipitation was concentrated by vacuum evaporation. Furfural was then prepared by subjecting the concentrated liquid to a reactor at 170℃ for 5 min, and the yield of furfural was 78.5%. The results of mass balance demonstrated that 1 000 g dried bamboo residues could produce 426.6 g of fermentable sugars(including 390.9 g glucose and 35.7 g xylose), 217.1 g lignin nanoparticles and 85.4 g furfural. Figures and Tables | References | Related Articles | Metrics

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The Adsorption Performance of Wear Elements in Lubricant by Activated Carbon Ruting XU, Jian ZHAO, Kang SUN, Xincheng LU, Yanping ZHANG, Jianchun JIANG 2022, 42 (4):  25-32.  doi: 10.3969/j.issn.0253-2417.2022.04.004 Abstract ( 305 )   HTML ( 286 )   PDF (644KB) ( 464 )   Save By using different activated carbons as adsorbents, the effects of pore size distribution and surface properties on the adsorption capacity of activated carbon for lubricant wear elements were studied, which based on the analysis of activated carbon by basic properties, specific surface area and pore structure, FT-IR, XPS and surface functional group analysis. The results showed that the mesopore volume and the contents of carboxyl and hydroxyl groups of activated carbon were the key factors affecting the adsorption capacity. Moreover, the adsorption effect of activated carbon on wear elements in simulated oil continuously increased with the increasing of the mesopore volume and the content of carboxyl and hydroxyl groups. Among the six kinds of activated carbons, AC4 with a mesopore volume of 0.901 cm3/g and a total carboxyl and hydroxyl group contents of 0.929 2 mmol/g, exhibited the best wear elements removal performances. Under the optimal adsorption conditions of temperature 80 ℃, adsorption time 60 min and additive amount of activated carbon 5%, the removal rates of Fe, Cu, Pb and Al in the simulated lubricant by AC4 were more than 95%. The removal effect of wear elements by activated carbon was significantly better than that of sawdust, activated clay, silica gel and filter paper, indicating that activated carbon could be used as an excellent adsorbent for waste lubricating oil regeneration and the high-performance material of oil filter. Figures and Tables | References | Related Articles | Metrics

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Synthesis of Blue and Green Lignin-based Luminescent Carbon Dots by Hydrothermal-Nitric Acid Oxidation Ying WANG, Bang AN, Mingcong XU, Jinquan YUE, Shouxin LIU, Wei LI 2022, 42 (4):  33-39.  doi: 10.3969/j.issn.0253-2417.2022.04.005 Abstract ( 337 )   HTML ( 305 )   PDF (8334KB) ( 502 )   Save Blue luminescent carbon quantum dots(B-CQDs) were synthesized by a simple one-step hydrothermal method using lignin and m-phenylenediamine as precursors. Green luminescent carbon quantum dots(G-CQDs) were synthesized by nitric acid oxidation. The optical properties and structures characteristics of these two CQDs were characterized by UV absorption spectroscopy, fluorescence spectroscopy, TEM, FT-IR and XPS. The cytotoxicity and cell imaging properties of G-CQDs were also tested. The results showed that nitric acid played an important role in the synthesis of G-CQDs. The oxidation of nitric acid increased the graphite N content, deepened the graphitization, passivated the surface state, and red-shifted the fluorescence emission wavelength. The results of structural characterization showed that the prepared B-CQDs and G-CQDs were mainly composed of C, N and O elements. All of them had abundant hydrophilic groups such as —OH, —NH, C—O and —COOH on the surface, which were monodisperse in water with the average particle size were 1.3 nm and 2.5 nm, respectively. The results of optical property analysis showed that the excitation wavelengths of B-CQDs and G-CQDs were Ex=392 nm and Ex=446 nm, and the corresponding emission wavelengths were 488 nm and 514 nm, respectively. They exhibited excitation-dependent fluorescence emission behavior and excitation-independent emission behavior, respectively. The results revealed that the possible emission mechanism of G-CQDs belonged to the bandgap fluorescence emissions based on conjugated π-domains. The synthesized G-CQDs with excellent photoluminescence, stable fluorescence and low cytotoxicity could be applied to bioimaging of HeLa cells. Figures and Tables | References | Related Articles | Metrics

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The Effects of Molecule Weight on the Crystallization Ability of Xylan Xuchen JIN, Zhouyang XIANG 2022, 42 (4):  40-46.  doi: 10.3969/j.issn.0253-2417.2022.04.006 Abstract ( 292 )   HTML ( 90 )   PDF (1511KB) ( 406 )   Save Using heterogeneous xylanase treatment on xylan, xylan samples(X0-X6) with different molecular weights were prepared by controlling the time of enzymatic hydrolysis. The enzyme treaeted xylans were dispersed/dissolved by 2% or 4% NaOH solutions and then re-precipitated by ethanol to prepare the alkali treated xylans. The effects of molecular weight on the crystallization ability of xylan were studied through X-ray diffraction(XRD) analyses on the enzyme treated and alkali treated xylan samples. The results showed that the weight average molecular weight(Mw), number average molecular weight(Mn) and polydispersity index(PDI) of xylan decreased to 25 700, 5 400 and 4.73, respectively, after heterogeneous xylanase treatment for 2.5 h. Then, with the further extension of enzymatic treatment time, the Mw of xylan changed slightly, while Mn decreased further, resulting in the increase of the PDI. It was found that the structure of xylan hydrate crystals was destroyed by heterogeneous xylanase treatment and subsequent heterogeneous alkali(2% NaOH solution) treatment, leading to the weakening of XRD peaks and the crystallinity decrease of xylan. Xylans with different molecule weights obtained by xylanase treatment were completely dissolved in 4% NaOH solution to prepare homogeneous solution. After re-precipitation, the XRD analysis showed that the complete crystalline structure of xylan hydrated crystal could be formed again, with almost unchanged crystallinity compared to that of unmodified xylan, indicating that heterogeneous reduction of the molecular weight of xylan had little influence on its crystallization ability. Figures and Tables | References | Related Articles | Metrics

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Preparation and Characterization of Peppermint Essential Oil Microcapsules Xiuming SONG, Yu LIU, Xiangyu XU, Lei SUN 2022, 42 (4):  47-53.  doi: 10.3969/j.issn.0253-2417.2022.04.007 Abstract ( 285 )   HTML ( 135 )   PDF (2488KB) ( 405 )   Save The microcapsules of peppermint essential oil were prepared by the composite coagulation method, which were made of natural polymer gelatin and arabian gum powder as wall materials, and peppermint essential oil as core material. The effects of different process conditions on the embedding rate and particle size of peppermint essential oil microcapsules were investigated by single-factor tests. The morphological structure and thermal stability of the microcapsules were also characterized by SEM, TEM, FT-IR and TG. The results showed that the oil content of microcapsules prepared was 44.9%, and the average particle size was 5.8 μm with the mass fraction of shell material 2%, ratio of core to shell 2∶1, the pH 3.7, the stirring speed 600 r/min and the curing time 6 h. The result of FT-IR confirmed that the essential oil of peppermint was successfully coated by wall materials. SEM and TEM analysis showed that the microcapsules were in the shape of regular round spheres, and the shell-wall materials were combined to form a "white-on-black" core-shell structure by electrostatic interaction, with a diameter of about 2 μm and a thickness of about 0.6 μm. The TG showed that the mass residue of peppermint essential oil was only 5.4% at 130 ℃. Comparatively, the mass loss of peppermint essential oil microcapsules could be found only at the temperature higher than 190 ℃, which showed that the thermal stability of peppermint essential oil was significantly improved after embedding. Thus, the quality loss and thermal stability of peppermint essential oil were improved by microencapsulation. Figures and Tables | References | Related Articles | Metrics

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Preparation, Characterization and Electrochemical Properties of Graphite Nanosheets/Bamboo Charcoal Composites Xuan YANG, Jianjun LAI, Hongfeng LI, Guanfeng LIN, Biao HUANG, Xinyu ZHENG 2022, 42 (4):  54-60.  doi: 10.3969/j.issn.0253-2417.2022.04.008 Abstract ( 296 )   HTML ( 11368 )   PDF (3003KB) ( 466 )   Save Based on mechanical force effect, graphite nanosheets/bamboo charcoal(GN/BC) composites with excellent electrochemical performance were prepared by high-energy ball milling and pulverization, and high-temperature carbonization using bamboo charcoal and flake graphite as raw materials. Meanwhile, the high-temperature porous bamboo charcoal(PBC) prepared without flake graphite was used as the control sample under the same conditions. The surface morphology and structure of the material were characterized by X-ray diffraction(XRD), Raman spectroscopy(Raman), scanning electron microscope(SEM) and specific surface area and pore distribution analyzer. The electrochemical performance of the product was tested by a three-electrode system. The results showed that the addition of flake graphite with higher crystallinity could improve the crystallinity of the composites. High-energy ball milling could break the graphite flakes into nanostructures and embed them in the bamboo charcoal. The specific surface area of the prepared GN/BC was 863.47 m2/g, the total pore volume was 0.56 cm3/g, the micropore volume was 0.26 cm3/g, and the average pore diameter was 2.58 nm. At a current density of 1A/g, the composite material had a high specific capacitance of 280.97 F/g and good rate performance. Figures and Tables | References | Related Articles | Metrics

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Analysis of Enzymatic Hydrolysis Process of High-solid Lignocellulose Materials Xiaoyan CHEN, Rongqing ZHANG, Yating JIAN, Qiang YU, Zhongming WANG, Zhenhong YUAN 2022, 42 (4):  61-67.  doi: 10.3969/j.issn.0253-2417.2022.04.009 Abstract ( 248 )   HTML ( 3791 )   PDF (594KB) ( 516 )   Save Focusing on alkali-treated bagasse, the effects of solid-liquid mixing methods, addition of three kinds of deep eutectic solvents(DES), feed method of fed-batch feeding, and the addition of xylanase on the enzymatic hydrolysis efficiency at high solid loading were investigated. The results showed that magnetic stirring could accelerate enzymatic hydrolysis speed, but had little effect on the efficiency of enzymatic hydrolysis. Negligible effect on enzymatic hydrolysis was observed by addition of low-concentration DES. A fed-batch with initial substrate loading of 150 g/L was fed at 12 and 36 h, respectively, which resulted in a total solid loading of 350 g/L for enzymatic hydrolysis. After enzymatic hydrolysis for 96 h, the total sugar concentration reached 162.7 g/L with the conversion rates of approximately 51% of both cellulose and hemicellulose. On the basis of fed-batch feeding, 1 000 IU/g hemicellulase was added, and the enzyme cocktail was used for enzymatic hydrolysis for 96 h. The total sugar concentration reached 218.9 g/L, and the conversion rate of cellulose and hemicellulose were 72% and 63%, respectively, which were 40% and 22% higher than those without the addition of hemicellulase. Figures and Tables | References | Related Articles | Metrics

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Chemical Constituents and Tyrosinase Inhibitory Activities from the Pink Flowers of Bauhinia variegata L. Meng LIANG, Yafeng WANG, Taojie XIE, Hongjie ZHU, Yonglin HUANG 2022, 42 (4):  68-74.  doi: 10.3969/j.issn.0253-2417.2022.04.010 Abstract ( 211 )   HTML ( 236 )   PDF (612KB) ( 420 )   Save The methanol extract of the pink flowers of Bauhinia variegata L. was isolated and purified by chromatography on Sephadex LH-20, MCI gel CHP 20P and Toyopearl Butyl-650C were used to isolate and purify, a total of 14 compounds were obtained. The structures of the compounds were identified by NMR spectroscopy, and their tyrosinase inhibitory activities were screened by the method of tyrosinase-catalyzed levodopa oxidation rate. Fourteen compounds isolated and purified from the pink flowers of B. variegata, were identified as pyrocatechol(1), protocatechuic acid(2), phydroybenzoic acid(3), 2, 5-dihydroxy methyl phenylacetate(4), trans-p-coumaric acid(5), cis-p-coumaric acid(6), caffeic acid(7), ethyl caffeic acid(8), trans ferulic acid(9), guaiacol β-D-glucopyranoside(10), p-hydroxybenzoic acid glucose ester(11), (E)-2, 3-dihydroxycyclopentyl-3-(3′, 4′-dihydroxyphenyl) acrylate(12), chlorogenic acid(13), and isoorientin(14) by spectral analysis and comparison with literature data. Compounds 5, 6, 9, 10, 11, 12, 14 were obtained from this plant for the first time. The results of tyrosinase inhibition activity test showed that, compounds 2 and 7 showed relatively good tyrosinase inhibitory activity with IC50 values of (4.804±0.939) g/L and (7.339±0.549) g/L, respectively. Their inhibitory activity increased with the increase of compound concentration, showing a positive dose-effect relationship. Figures and Tables | References | Related Articles | Metrics

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Application Performance Comparison of Lignin-based Phenolic Resin with High Phenol Substitution Rate in Plywood Hui ZHAO, Yanru XU, Hao REN 2022, 42 (4):  75-80.  doi: 10.3969/j.issn.0253-2417.2022.04.011 Abstract ( 264 )   HTML ( 314 )   PDF (473KB) ( 466 )   Save Lignin-based phenolic resin(LPF)with high phenol substitution rate(≥70%) were synthesized based on alkali lignin(UL)from black liquor of kraft pulping of spruce, or based on demethylated lignin(DUL) and hydroxymethylated lignin(HUL) obtained from the modification of UL. The effects of the hydroxyl content of three types of lignin on the adhesive strength and free formaldehyde content of LPF adhesives were compared and analyzed in this paper. The results of structure analysis of lignin showed that the hydroxyl ratios of DUL and HUL increased by 26.41% and 72.35%, respectively, while compared to raw UL. UL, DUL and HUL were separately used to replace phenol for the preparation of LPF that were applied in the bonding experiment of poplar veneer. The experimental results showed that demethylation of UL could further improve the heat-resistant water-based bonding strength((σHWT). At 30% lignin substitution rate, DUL showed the largest σHWT of 1.09 MPa, which was 39.39% higher than PF(0.78 MPa). The replacement rate of lignin increased from 30% to 70%. Meanwhile, the content of free formaldehyde in plywood decreased from 0.33 mg/L to 0.29 mg/L, which was still less than the requirement of national standard GB 9846.2—2004(< 0.5 mg/L). The bonding strength of LPF prepared from HUL was significantly improved after modification of UL by hydroxymethylation. At 30% lignin replacement rate, the dry bonding strength(σdry) and wet bonding strength(σWST) were 2.55 MPa and 1.99 MPa which increased by 79.02% and 135.31% respectively, while compared those with PF(1.43 MPa and 0.84 MPa). Figures and Tables | References | Related Articles | Metrics

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Shellac-based CQDs were Used to Detect Tetracycline Hydrochloride Hongyan XU, Jinzhi YE, Qi ZHANG, Jiajia LIU, Lanxiang LIU 2022, 42 (4):  81-87.  doi: 10.3969/j.issn.0253-2417.2022.04.012 Abstract ( 364 )   HTML ( 165 )   PDF (3376KB) ( 390 )   Save Using bleached shellac as raw material, water soluble shellac-based carbon quantum dots(shellac-CQDs) with blue fluorescence were synthesized by hydrothermal and one-step synthesis method. Their composition and structure were characterized by Fourier transform infrared spectroscopy(FT-IR), X-ray photoelectron spectroscopy(XPS), transmission electron microscopy(TEM) and dynamic light scattering(DLS). The analysis results showed that shellac-CQDs mainly contained C and O elements, which were composed of aromatic ring structure and a large number of oxygen-containing functional groups, with an average particle size of 2.0 nm. The spectral tests showed that the maximum excitation wavelength and emission wavelength of shellac-CQDs were 320 and 432 nm, respectively. The maximum absorption wavelength in the UV-Vis spectrum was 289 nm. Based on the good fluorescence properties of shellac-CQDs and the quenching effect of tetracycline hydrochloride on its fluorescence, a new method for the detection of tetracycline hydrochloride using shellac-CQDs as fluorescence sensor was established. The results showed that there was a good linear relationship between the fluorescence peak areas and the concentration of tetracycline hydrochloride in the range of 0.02-0.10 g/L. The detection limit of this method was 0.01 g/L. It has been preliminarily applied to the detection of tetracycline hydrochloride in tap water or feed, and the recovery rate of the samples was 96.9%-107.7%, and the relative standard deviation(RSD) was between 1.9% and 5.5%, indicating that this method has high accuracy, good repeatability and potential practical application value. Figures and Tables | References | Related Articles | Metrics

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Inhibitory Effect and Mechanism of Quaternary Ammonium Salts Containing Hydrogenated Nobyl on Sphaeropsis sapinea Jiayu CHANG, Qingying DING, Zhuanquan XIAO, Zongde WANG, Ji ZHANG, Shangxing CHEN 2022, 42 (4):  88-94.  doi: 10.3969/j.issn.0253-2417.2022.04.013 Abstract ( 233 )   HTML ( 197 )   PDF (3153KB) ( 407 )   Save Three series of 36 quaternary ammonium salts containing hydrogenated nopyl were synthesized using β-pinene as the starting material. Their inhibitory rates on pathogenic fungi of Sphaeropsis sapinea were tested. The inhibitory mechanism of four compounds including bis(hydrogenated nopyldimethylammonium bromide)(14), hexamethylene-1, 6-bis(hydrogenated nopyldimethylammonium chloride)(26), tetramethylene-1, 4-bis(hydrogenated nopyldiethylammonium bromide)(28) and 1, 4-dibenzyl-bis(hydrogenated nopyldimethylammonium bromide)(31) on pathogenic fungi of S. sapinea were preliminarily explored from three aspects of mycelial dry weight, cell membrane permeability and mycelial structure. The results showed that most of the quaternary ammonium salt compounds containing hydrogenated nopyl had good inhibitory effect on S. sapinea, and the inhibitory effect of gemini quaternary ammonium salts containing hydrogenated nopyl on S. sapinea were stronger than that of single quaternary ammonium salts. The inhibitory rates of most quaternary ammonium salt compounds containing hydrogenated nopyl were more than 90% or even 100%, at a mass concentration of 50 mg/L, which were much higher than those of commonly used fungicides chlorothalonil and carbendazim. The preliminary antibacterial mechanism study showed that the dry weight of mycelium decreased, the relative conductivity increased significantly, and the morphology and structure of mycelium changed significantly when they were treated by above-mentioned four compounds. Based on these phenomena, we speculated that quaternary ammonium compounds could inhibit the mycelial growth of S. sapinea by damaging the integrity of cell membrane and changing the morphology and structure of mycelium. Figures and Tables | References | Related Articles | Metrics

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Chemical Constituents of Triterpenes from Sabia discolor Dunn Lili ZHU, Linjing ZHONG, Mengjuan XU, Junkun CHEN, Linfu LIANG 2022, 42 (4):  95-100.  doi: 10.3969/j.issn.0253-2417.2022.04.014 Abstract ( 260 )   HTML ( 193 )   PDF (648KB) ( 321 )   Save The ethanol extracts from the stem of Sabia discolor Dunn were isolated and purified by silica gel and Sephadex LH-20 column chromatography. The structures of the compounds were verified by modern spectroscopy(MS, 1H NMR, 13C NMR). Ten pentacyclic triterpenoids were isolated from the stem of S. discolor, and identified as 20-hydroxy-lupan-3-one(1), monogynol A(2), (20S)-3-oxo-20-hydroxytaraxastane(3), 20-taraxastene-3α, 28-diol(4), 3β, 20β-dihydroxytaraxastane(5), oleanolic acid(6), 1-oxo-erythrodiol(7), juglangenin A(8), castanopsol(9) and 1α, 3β-dihydroxyl-olean-12-en-28-oic acid(10), respectively. Among them, compounds 2, 4, 7, 8 and 9 were obtained from the genus Sabia for the first time, and compounds 1, 3, 5 and 10 were isolated from this plant for the first time. Figures and Tables | References | Related Articles | Metrics

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Formaldehyde/Dioxane Pretreatment on Bamboo for Producing Monosaccharide and Lactic Acid Tengfei MA, Yawei ZHAN, Yue LIU, Zhiqiang LI 2022, 42 (4):  101-106.  doi: 10.3969/j.issn.0253-2417.2022.04.015 Abstract ( 268 )   HTML ( 275 )   PDF (2927KB) ( 453 )   Save Using bamboo as raw material, the effect of formaldehyde/1, 4-dioxane pretreatment on the yield of enzymatic hydrolysis sugar from bamboo cellulose was studied. The producing process of lactic acid through fermentation with the enzymatic hydrolysate was also investigated. The results showed that the pretreatment could remove lignin and greatly increase the cellulose content of the pretreated bamboo substrate, with cellulose content reaching 75.6%-90.7%. The highest yield of cellulose-to-glucose by enzymatic hydrolysis after pretreatment was 92.8%. The enzymatic hydrolysate could be directly used for fermentation to produce lactic acid, and the yield of the glucose to lactic acid could reach 73.2%. The changes of bamboo structure before and after pretreatment were observed by scanning electron microscope(SEM), X-ray diffraction(XRD) and ion chromatograph. After pretreatment, the bamboo surface curled, the wax layer on the surface of bamboo was almost completely dissolved and removed, and the structure became loose. Figures and Tables | References | Related Articles | Metrics

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Research Progress on Separation of Active Components from Forest Sources by Targeted Molecular Imprinting Materials Mujie LYU, Litao WANG, Jiandong WANG, Jinsong CAO, Haojie JIN, Yujie FU 2022, 42 (4):  107-118.  doi: 10.3969/j.issn.0253-2417.2022.04.016 Abstract ( 271 )   HTML ( 1849 )   PDF (3214KB) ( 542 )   Save China was rich in forest resources, and it was an important direction and approach of the development of forestry industry for exploiting the active components of forest resources which were beneficial to human health. With the rapid development of forestry bio-agent industry based on the active components as important material basis in China, targeted molecular imprinting materials have important industrial application value in the accurate separation and high-value processing of forest active components. This article introduced the principle and classification of targeted molecular imprinting technology, as well as the carrier types of several new-style targeted molecularly imprinted adsorption materials in recent years, mainly include graphene, silica, carbon dots and bio-based carriers. It focused on the application status in the separation of flavonoids, polyphenols, alkaloids, organic acids and other forest source active ingredients by targeted molecularly imprinted adsorption materials. Finally, the development of targeted molecular imprinting materials for the separation of active components from forest sources was summarized and prospected, the limitation of targeted molecular imprinting materials and the development trend of targeted molecular imprinting materials in the separation of active components from forest sources were also analyzed. Figures and Tables | References | Related Articles | Metrics

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Application of Aspen Plus in Lignocellulosic Biomass Pretreatment for Ethanol Production: A Review Fang WANG, Hongdan ZHANG 2022, 42 (4):  119-130.  doi: 10.3969/j.issn.0253-2417.2022.04.017 Abstract ( 421 )   HTML ( 5932 )   PDF (2999KB) ( 683 )   Save Pretreatment was a key step in sugar platform -based biomass refinery using lignocellulosic biomass as raw material. In this paper, the advantages and disadvantages of the commonly used methods such as dilute acid/alkali, steam explosion, liquid hot water, microwave, subcritical CO2, ionic liquids, deep-eutectic solvents, organosolv, milling/grinding, and biological, and the research progress of subsequent enzymatic hydrolysis and fermentation were reviewed. Furthermore, the application of the co-production of ethanol and platform chemicals in the pretreatment of biomass feedstock at home and abroad based on Aspen Plus and techno-economic analysis were introduced. Finally, the drawbacks of Aspen Plus in biomass pretreatment for ethanol production were summarized and the further research directions were proposed. Figures and Tables | References | Related Articles | Metrics