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New Antibacterial Dihydropyrones Induced by Co-Culture of Penicillium crustosum PRB-2 and Penicillium citrinum HDN11-186
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作者 YU Guihong ZHOU Luning +1 位作者 WU Guangwei LI Dehai 《Journal of Ocean University of China》 CAS CSCD 2024年第1期216-220,共5页
Two new dihydropyrones,rhytismatones C(1)and D(2),and a known compound,penicillenol A1(3),were isolated from the co-culture broth of the deep-sea-derived fungus Penicillium crustosum PRB-2 and Suaeda salsa-derived end... Two new dihydropyrones,rhytismatones C(1)and D(2),and a known compound,penicillenol A1(3),were isolated from the co-culture broth of the deep-sea-derived fungus Penicillium crustosum PRB-2 and Suaeda salsa-derived endophytic fungus Peni-cillium citrinum HDN11-186.Their structures were elucidated through comprehensive analysis of nuclear magnetic resonance(NMR)spectra and mass spectra.The absolute configurations of new compounds were determined by calculating the electronic circular di-chroism(ECD)spectrum.UPLC-MS data showed that compounds 1–3 could only be detected in the media of co-culture,suggesting new biosynthetic pathways were activated in the co-cultured fungi.Compound 1 showed obvious antibacterial activities against Pro-teus sp.MMBC-1002 and Bacillus subtilis MMBC-1004 with minimum inhibitory concentration(MIC)both at 25μmolL^(-1). 展开更多
关键词 CO-CULTURE Penicillium crustosum Penicillium citrinum dihydropyrones antibacterial activity
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Porous heterostructure of graphene/hexagonal boron nitride as an efficient electrocatalyst for hydrogen peroxide generation 被引量:2
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作者 Mengmeng Fan Zeming Wang +10 位作者 Yuying Zhao Qixin Yuan Jian Cui Jithu Raj Kang Sun Ao Wang Jingjie Wu Hao Sun Bei Li Liang Wang Jianchun Jiang 《Carbon Energy》 SCIE CSCD 2023年第5期138-151,共14页
Compared with the traditional heteroatom doping,employing heterostructure is a new modulating approach for carbon-based electrocatalysts.Herein,a facile ball milling-assisted route is proposed to synthesize porous car... Compared with the traditional heteroatom doping,employing heterostructure is a new modulating approach for carbon-based electrocatalysts.Herein,a facile ball milling-assisted route is proposed to synthesize porous carbon materials composed of abundant graphene/hexagonal boron nitride(G/h-BN)heterostructures.Metal Ni powder and nanoscale h-BN sheets are used as a catalytic substrate/hard template and“nucleation seed”for the formation of the heterostructure,respectively.As-prepared G/h-BN heterostructures exhibit enhanced electrocatalytic activity toward H_(2)O_(2) generation with 86%-95%selectivity at the range of 0.45-0.75 V versus reversible hydrogen electrode(RHE)and a positive onset potential of 0.79 versus RHE(defined at a ring current density of 0.3 mA cm^(-2))in the alkaline solution.In a flow cell,G/h-BN heterostructured electrocatalyst has a H_(2)O_(2) production rate of up to 762 mmol g_(catalyst)^(-1) h^(-1) and Faradaic efficiency of over 75%during 12 h testing,superior to the reported carbon-based electrocatalysts.The density functional theory simulation suggests that the B atoms at the interface of the G/h-BN heterostructure are the key active sites.This research provides a new route to activate carbon catalysts toward highly active and selective O_(2)-to-H_(2)O_(2) conversion. 展开更多
关键词 efficient electrocatalyst GRAPHENE H_(2)O_(2)generation hexagonal boron nitride porous heterostructure
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Co@CoO:An efficient catalyst for the depolymerization and upgrading of lignocellulose to alkylcyclohexanols with cellulose intact 被引量:1
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作者 Shuang Xiang Lin Dong +5 位作者 Zhiqiang Wang Xue Han Yong Guo Xiaohui Liu Xue-Qing Gong Yanqin Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期191-199,I0006,共10页
The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key meth... The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key method in"lignin-first"strategy,Recently,we found that a core-shell structured Co@CoO catalyst with CoO shell as the real active site had excellent performance in the hydrogenolysis of 5-hydromethylfurfural to 2,5-dimethylfuran due to its unique ability to dissociate H_(2)and yield active H^(δ-)species(Xiang et al.,2022).In this work,we report a one-pot depolymerization and upgrading of lignocellulose to alkylcyclohexanols,a flavour precursor,with intact cellulose over this unique core-shell structured catalyst,Co@CoO.Lignin model compounds(β-O-4,4-O-5,α-O-4)were first used to clarify the activity of Co@CoO catalyst.Then,the one-pot conversion of various organosolv lignin(birch,pine and poplar)to alkylcyclohexanols was realized with the mass yield of alkylcyclohexanols up to25.8 wt%from birch lignin under the reaction condition of 210℃,1 MPa H_(2),16 h.Finally,the corresponding woody sawdusts were used as feedstocks and found that the Co@CoO catalyst indeed preferentially depolymerized and upgraded the lignin part and obtained the same alkylcyclohexanols products with the retention of cellulose-rich pulp.The collected alkylcyclohexanols were further esterified to obtain valueadded esters,which can be used as flavors.This work will inspire the design of new efficient metal oxide catalysts in lignin fractionation and depolymerization to high-value-added chemicals with intact cellulose. 展开更多
关键词 LIGNOCELLULOSE LIGNIN DEPOLYMERIZATION Co@CoO Alkylcyclohexanols
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Effect of PyC Interface Thickness on the Heat-stability of Cansas-ⅡSiC_(f)/SiC Composites 被引量:1
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作者 韩笑 于国强 +4 位作者 张盛 SHI Jian GAO Xiguang SONG Yingdong WANG Fang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第4期725-734,共10页
The effect of the pyrolytic carbon(PyC)interface thickness on the heat-stability of CansasⅡSiC_(f)/SiC composites under Ar up to 1500℃was studied in detail.After the heat treatment at 1500℃for 50 h,the interface bo... The effect of the pyrolytic carbon(PyC)interface thickness on the heat-stability of CansasⅡSiC_(f)/SiC composites under Ar up to 1500℃was studied in detail.After the heat treatment at 1500℃for 50 h,the interface bonding strength of the thin interface(about 200 nm)decreases from 74.4 to 20.1 MPa(73.0%),while that of the thick interface(about 2μm)declines from 7.3 to 3.2 MPa(52.7%).At the same time,the decline fraction of strength of the composites with the thin interface is 12.1%,less than that with the thick interface(42.0%).The fiber strength also decreases after heat treatment,which may be due to the significant growth ofβ-SiC grains and critical defects.The different heat-stability of the interface with the thin and thick thickness might be related to the inconsistency of the degree of the graphitization of PyC.Compared with the composites with the thick interface,the composites with the thin interface remained higher tensile strength after heat treatment due to the better interface bonding strength.The interface with strong bonding strength could protect the fiber by postponing the decomposition of amorphous phases SiC_(x)O_(y) and hindering the generation of fiber defects. 展开更多
关键词 SiC_(f)/SiC mini-composites heat-stability interface thickness mechanical properties microstructure
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Chemical characterization of smoke from the production process of wood-plastic composites
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作者 Wang Shi-fa Zhang Ai-jun 《Forestry Studies in China》 CAS 2007年第1期57-62,共6页
The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust (Fraxinus mandschurica Rupr.) and polypropylene powder as the raw material, w... The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust (Fraxinus mandschurica Rupr.) and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290℃ during 8 min (the conditions were similar to those employed on an industrial scale). The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry (GC-MS). The analytical results showed that the unpleasant smell was emitted from the pyrogenation of wood sawdust rather than from the polypropylene powder. Nine types of compounds (hydrocarbons, ethers, phenols, aldehydes, ketones, alcohols, acids and their derivatives, furan and its derivatives, and nitrogen-containing compounds) were collected in the gas phase during heating. Among those 126 components detected by GC-MS, 112 compounds were identified. 展开更多
关键词 wood-plastic composite unpleasant smell pyrogenation Manchurian ash sawdust polypropylene powder
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Effective depolymerization of alkali lignin using an attapulgite-Ce_(0.75)Zr_(0.25)O_(2)(ATP-CZO)-supported cobalt catalyst in ethanol/isopropanol media
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作者 Jiajia Chen Xinyu Lu +2 位作者 Dandan Wang Pengcheng Xiu Xiaoli Gu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期50-62,共13页
Lignin is the world's greatest renewable aromatic biofeedstock,and it has promising applications in high value-added chemical products.Herein,N-Co/ATP-CZO was used as a catalyst for the depolymerization of alkali ... Lignin is the world's greatest renewable aromatic biofeedstock,and it has promising applications in high value-added chemical products.Herein,N-Co/ATP-CZO was used as a catalyst for the depolymerization of alkali lignin in ethanol and isopropanol systems,and explored the effects of formic acid(FA)amount,reaction time,reaction temperature and other factors on the depolymerization of alkali lignin.Among them,formic acid serves as both catalytic and in situ-hydrogen donor.Ultimately,the highest yield of bio-oil(59.28%(mass)),including 30.05%(mass)of monomer,was obtained after a reaction of FA to alkali lignin mass ratio of 4 and 240°C for 8 h.Among the monomers,the yield of Guaiacol was the highest(5.94%(mass)),followed by 2-methoxy-4-methylphenol(5.74%(mass)).This study,the modification of attapulgite was carried out to reduce the acidity while enhancing the catalytic activity for depolymerization,and the selection of hydrogen donor was investigated.A feasible pathway for lignin depolymerization research was opened. 展开更多
关键词 Lignin Biofuel Catalyst support Mixing Ce_(0.75)Zr_(0.25)O_(2)solid solution
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The case-dependent lignin role in lignocellulose nanofibers preparation and functional application-A review
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作者 Xiya Zhang Lili Zhang +1 位作者 Yimin Fan Zhiguo Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1553-1566,共14页
Lignocellulose nanofibers(LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the imp... Lignocellulose nanofibers(LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the important role of these two stages. This review discussed the interaction between lignin and chemicals in the pretreatment stage, and discovered the general law of the effect of lignin in the mechanical fibrillation stage.Lignin exhibits both promotion and inhibition effects on mechanical fibrillation, and the mutual competition between the two effects ultimately affects the energy consumption, morphology and yield of LCNFs. Furthermore, the recent research progress related to the contributions of lignin on the functional application of LCNFs was summarized, aiming to provide profound guidance for the preparation and application of LCNFs. 展开更多
关键词 Lignocellulose nanofibers LIGNIN FIBRILLATION CELLULOSE PRETREATMENT
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Synthesis and Properties of Rosin-Based Composite Acrylamide Hydrogels
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作者 Shuangsheng Zhang Bin Sun +3 位作者 Siyu Li Xiangyu Lin Muhua Chen Xu Xu 《Journal of Renewable Materials》 SCIE EI 2023年第2期853-865,共13页
Hydrogels have been widely applied in agricultural drought-resistance,pollution regulation,drug delivery and so on.Acrylamide(AM)is usually used as raw material to synthesize acrylamide hydrogels.However,inherently lo... Hydrogels have been widely applied in agricultural drought-resistance,pollution regulation,drug delivery and so on.Acrylamide(AM)is usually used as raw material to synthesize acrylamide hydrogels.However,inherently low mechanical strength greatly limits their applications in some special areas.Therefore,it is necessary to choose suitable functional monomers to optimize acrylamide hydrogels and improve their mechanical performances.In this paper,a novel acrylamide monomer modified by rosin was synthesized,and then polyacrylamide/rosinbased acrylamide(RAM)composite hydrogels were prepared via free radical polymerization using potassium persulfate as initiator,N,N′-methylene-bisacrylamide(MBA)as a crosslinker.The influence of RAM monomer was investigated in detail.The chemical structure,pore structure,swelling properties,thermal performances and mechanical properties of composite hydrogels were characterized by Fourier Transform Infrared spectrometer(FT-IR),thermogravimetric analysis(TG),scanning electron microscope(SEM),and universal testing,respectively.The results showed that the thermal stability and mechanical property of RAM hydrogels were improved significantly.The compressive strength of RAM hydrogels was increased to 3.5 times than that of AM hydrogels,and the tensile strength was 5.1 times compared with AM hydrogels as well.Moreover,RAM hydrogels exhibited a faster initial swelling rate due to the new pore structure formed after introducing the RAM monomer. 展开更多
关键词 HYDROGEL ROSIN swelling property mechanical property thermal stability
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Lignin‐derived carbon with pyridine N‐B doping and a nanosandwich structure for high and stable lithium storage
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作者 Dichao Wu Jiayuan Li +5 位作者 Yuying Zhao Ao Wang Gaoyue Zhang Jianchun Jiang Mengmeng Fan Kang Sun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期232-247,共16页
Biomass‐derived carbon is a promising electrode material in energy storage devices.However,how to improve its low capacity and stability,and slow diffusion kinetics during lithium storage remains a challenge.In this ... Biomass‐derived carbon is a promising electrode material in energy storage devices.However,how to improve its low capacity and stability,and slow diffusion kinetics during lithium storage remains a challenge.In this research,we propose a“self‐assembly‐template”method to prepare B,N codoped porous carbon(BN‐C)with a nanosandwich structure and abundant pyridinic N‐B species.The nanosandwich structure can increase powder density and cycle stability by constructing a stable solid electrolyte interphase film,shortening the Li^(+) diffusion pathway,and accommodating volume expansion during repeated charging/discharging.The abundant pyridinic N‐B species can simultaneously promote the adsorption/desorption of Li^(+)/PF_(6)^(−) and reduce the diffusion barrier.The BN‐C electrode showed a high lithium‐ion storage capacity of above 1140 mAh g^(−1) at 0.05 A g^(−1) and superior stability(96.5% retained after 2000 cycles).Moreover,owing to the synergistic effect of the nanosandwich structure and pyridinic N‐B species,the assembled symmetrical BN‐C//BN‐C full cell shows a high energy density of 234.7Wh kg^(−1),high power density of 39.38 kW kg−1,and excellent cycling stability,superior to most of the other cells reported in the literature.As the density functional theory simulation demonstrated,pyridinic N‐B shows enhanced adsorption activity for Li^(+) and PF_(6)^(−),which promotes an increase in the capacity of the anode and cathode,respectively.Meanwhile,the relatively lower diffusion barrier of pyridinic N‐B promotes Li^(+) migration,resulting in good rate performance.Therefore,this study provides a new approach for the synergistic modulation of a nanostructure and an active site simultaneously to fabricate the carbon electrode material in energy storage devices. 展开更多
关键词 high cycling stability high energy density lithium‐ion batteries pyridinic N‐B species sandwich structure carbon nanosheet
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A mini-review on the modeling of volatile organic compound adsorption in activated carbons: Equilibrium, dynamics, and heat effects 被引量:4
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作者 Shanshan Wang Liangliang Huang +2 位作者 Yumeng Zhang Licheng Li Xiaohua Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第3期153-163,共11页
The research on the adsorption equilibria,kinetics,and increase in process temperature of the volatile organic compound(VOC)adsorption in porous materials ensures safe production,thereby reducing production costs and ... The research on the adsorption equilibria,kinetics,and increase in process temperature of the volatile organic compound(VOC)adsorption in porous materials ensures safe production,thereby reducing production costs and improving separation efficiency.Therefore,it is critical in predicting the entire adsorption process based on minimal or no experimental input of the adsorbate and adsorbent.We discuss,in this review,the factors that affect the adsorption performance of VOCs in activated carbons,including the adsorption equilibrium,adsorption kinetics,and exotherm during adsorption.Subsequently,the existing prediction models are summarized and compared concerning the adsorption equilibrium,adsorption kinetics,and exothermic process of adsorption.We then propose a new prediction model based on intermolecular interaction and provide an outlook toward the design and manipulation of efficient adsorbents for the VOC system. 展开更多
关键词 Volatile organic compounds Activated carbon Adsorption equilibria Adsorption kinetics Adsorption exotherm
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Synthesis,Crystal Structure and Antitumor Activity of a New 3H-Phenanthro-[2,1-d]imidazole Derivative of Dehydroabietic Acid 被引量:3
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作者 谷文 苗婷婷 +3 位作者 王石发 郝云 张康平 金晓燕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1440-1445,共6页
The title compound (CI9H24BrN302, 3) was synthesized from dehydroabietic acid and its crystal structure was determined by single-crystal X-ray diffraction. The compound is of monoclinic system, slSace group C2 with ... The title compound (CI9H24BrN302, 3) was synthesized from dehydroabietic acid and its crystal structure was determined by single-crystal X-ray diffraction. The compound is of monoclinic system, slSace group C2 with a = 24.830(5), b = 7.1410(14), c = 13.981(3) A, p = 107.68(3)°, Z = 4, V= 2361.9(8) A3, Mr = 482.42, Dc = 1.357 Mg/m3, S = 1.003,μ = 1.772 mm1, F(000) = 1008, the final R = 0.0660 and wR = 0.1402 for 2244 observed reflections (I 〉 2o(/)). The crystal structure is stabilized by four hydrogen bonds (O(W)-H(WA)...O(3), O(W)-H(WB)...O(1), N(2)-H(2A)...O(W) and N(3)-H(3A)...N(1)) formed among the title compound, the crystal water and acetone molecules. The preliminary antitumor assay showed the title compound exhibited considerable inhibitory activity against HepG2 and SMMC-7721 cell lines with the ICs0 values of 17.1 and 10.2 μM, respectively. 展开更多
关键词 dehydroabietic acid 3H-phenanthro[2 1-d]imidazole crystal structure ANTITUMOR
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Syntheses, Crystal Structures and Antibacterial Activities of Two New Methyl 12-Alkylamino-13,14-dinitrodeisopropyl-dehydroabietates 被引量:2
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作者 CHEN Hao GENG Yi +1 位作者 WANG Shi-Fa GU Wen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第2期257-262,167,共7页
The title compounds(5 a and 5 b) were synthesized from dehydroabietic acid and characterized by MS, IR, NMR and elemental analysis. The crystal structure of compound 5 a was determined by single-crystal X-ray diffract... The title compounds(5 a and 5 b) were synthesized from dehydroabietic acid and characterized by MS, IR, NMR and elemental analysis. The crystal structure of compound 5 a was determined by single-crystal X-ray diffraction. The compound is of monoclinic system, space group P21 with a = 8.0860(16), b = 14.011(3), c = 9.799(2) ?, β = 106.31(3)?, Z = 2, V = 1065.5(4) ?3, Mr = 431.48, Dc = 1.345 Mg/m3, S = 1.002, μ = 0.099 mm-1, F(000) = 460, the final R = 0.0617 and wR = 0.1532 for 1397 observed reflections(I > 2σ(I)). The preliminary antibacterial assay showed that compound 5 a exhibited considerable inhibitory activity against Bacillus subtilis, Staphylococcus aureus and Methicillin-resistant S. aureus(MRSA) with MIC values of 2~8 μg/mL. 展开更多
关键词 dehydroabietic ACID synthesis CRYSTAL structure ANTIBACTERIAL activity
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Recent Technologies for the Extraction and Separation of Polyphenols in Different Plants:A Review 被引量:3
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作者 Yingying Hu Bowen Yan +3 位作者 Zhefan Stephen Chen Lei Wang Wei Tang Caoxing Huang 《Journal of Renewable Materials》 SCIE EI 2022年第6期1471-1490,共20页
Polyphenol is an important secondary metabolite with unique physiological functions and biological activity.The polyphenols in different plants and biomass have different chemical structures,which needs various extrac... Polyphenol is an important secondary metabolite with unique physiological functions and biological activity.The polyphenols in different plants and biomass have different chemical structures,which needs various extraction methods to obtain them.Recently,plant polyphenols and their application research in food and medicine have become a research hotspot,which is mainly focused on preparation,purification,structural identification,and biological activity assays.Among these researches,extraction and separation are the key sections to investigate the structure and activity of polyphenol.Hence,this review summarized the recent extraction and separation techniques of polyphenol,including solvent extraction,supercritical fluid extraction,ultrasonic extraction,enzymatic extraction,resin adsorption extraction,and electric field method,etc.In addition,this review also reveals the current problems and proposes future extraction research of polyphenol.It is hoped that this review will provide a guide for the researchers who are actively committed to promoting progress in the field of polyphenolics. 展开更多
关键词 PLANTS POLYPHENOLS EXTRACTION SEPARATION
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Insights into depolymerization pathways and mechanism of alkali lignin over a Ni_(1.2)-ZrO_(2)/WO_(3)/γ-Al_(2)O_(3)catalyst 被引量:2
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作者 Xinyu Lu Dandan Wang +7 位作者 Haoquan Guo Pengcheng Xiu Jiajia Chen Yu Qin Hossain Mahmud Robin Chaozhong Xu Xingguang Zhang Xiaoli Gu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第8期191-201,共11页
This study performed catalytic depolymerization of alkali lignin over Ni-based catalysts.Effects of different promoters(Zr and W),Ni loadings,reaction temperatures,and the addition of formic acid and catalyst on ligni... This study performed catalytic depolymerization of alkali lignin over Ni-based catalysts.Effects of different promoters(Zr and W),Ni loadings,reaction temperatures,and the addition of formic acid and catalyst on lignin conversion and products distribution were all investigated.The result showed that the highest oil yield(40.1%(mass))was obtained at 240℃over Ni_(1.2)/γ-Al_(2)O_(3) promoted by Zr and W species.Quantitative analysis indicates that Zr and W species prefer to lignin depolymerization while Ni active phase prefer to hydrodeoxygenation and hydrogenation.The interconversion of products derived from lignin depolymerization was determined by gas chromatography-mass spectrometer,which demonstrated that phenolic compounds were dominant products in all lignin derived bio-oils,wherein the proportion of vanillin was highest(65.7%)at 180℃,while that of alkyl guaiacols increased with the increase of temperature(from 12.45%at 180℃ to 66.67%at 240℃).Residual lignin obtained after lignin depolymerization was also investigated for detecting differences on functional groups,wherein the disappearing peaks at 1511 cm^(-1)(stretching of aromatic rings),1267,1215 and 1035 cm^(-1)(vibrations of guaiacyl and syringyl units)were detected by Fourier transform infrared spectrometry.Additionally,the higher O/C ratio measured by elemental analysis also confirmed that alkali lignin was depolymerized effectively under mild conditions. 展开更多
关键词 Alkali lignin Formic acid Chemical reduction Phenolic compounds
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Synthesis,Crystal Structure and Cytotoxic Activity of a New N-Vinyl-1H-dibenzo[a,c]carbazole Derivative of the Dehydroabietic Acid 被引量:1
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作者 GU Wen HAO Yun +1 位作者 CHEN Hong-Tu WANG Shi-Fa 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第12期1904-1910,共7页
The title compound (C29H33NO2, 3) was synthesized and structurally characterized by elemental analysis, IR, MS, 1H- and 13C-NMR and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group ... The title compound (C29H33NO2, 3) was synthesized and structurally characterized by elemental analysis, IR, MS, 1H- and 13C-NMR and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P21 with a = 14.428(3), b = 7.3440(15), c = 22.768(5) A, β = 95.17(3)°, V = 2402.7(8) A3, Z = 4, Mr = 427.56, Dc = 1.182 g/cm3, F (000) = 920, 2(MoKa) = 0.71073 A,μ = 0.073 mm-1, the final R= 0.0670 and wR= 0.1002 for 2437 reflections with I〉 2σ(I) Two crystallographically independent molecules with different conformations co-exist in the structure. The crystal structure is stabilized by intermolecular C-H…π interactions which make the molecules stack along the b axis. In addition, the preliminary cytotoxic assay showed that the title compound exhibited moderate inhibitory activity against KB and SW1116 cells. 展开更多
关键词 dehydroabietic acid crystal structure 1H-dibenzo[a c]carbazole cytotoxic activity
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A Review of Lignocellulosic Biomass Pretreatment Technologies 被引量:5
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作者 Caoxing Huang Jiao Liu +2 位作者 Wenhui Geng Wei Tang Qiang Yong 《Paper And Biomaterials》 CAS 2021年第3期61-76,共16页
Lignocellulose is the most abundant renewable resource on earth.However,owing to the tightly entangled structural characteristics,it is challenging to convert lignocellulose into bio-based products in the biorefinery ... Lignocellulose is the most abundant renewable resource on earth.However,owing to the tightly entangled structural characteristics,it is challenging to convert lignocellulose into bio-based products in the biorefinery process without pretreatment.Pretreatment can destroy the natural resistance structure of lignocellulosic biomass,which is conducive to its downstream enzymatic saccharification and fermentation process.Physical,chemical,and physicochemical pretreatments have been widely conducted for lignocellulosic biomass;several updated approaches and peculiar chemicals have also been proposed for these pretreatment methods in the recent years.Hence,this study comprehensively reviews the novel technologies and chemicals that were applied in the various pretreatments.In addition,the mechanisms,advantages,and disadvantages of the updated pretreatments are discussed to provide a reference for developing new pretreatment methods. 展开更多
关键词 lignocellulosic biomass PRETREATMENT enzymatic hydrolysis BIOETHANOL
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Synthesis, Photo-physical Properties and Cell Imaging of Meso-2,6-dichlorophenyl Boron-dipyrromethene Derivatives 被引量:1
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作者 TAO Jia-Yu SONG Wen-Ting +4 位作者 SUN Lei LI Zheng-Zheng FU Bo CAI Zheng-Chun XU Hai-Jun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第9期1503-1510,共8页
The meso-2,6-dichlorophenyl boron-dipyrromethene(BODIPY) derivative 1 was synthesized and characterized by single-crystal X-ray diffraction analysis, 1 H NMR and Esi-HRMS. Compound 1 crystallizes in monoclinic, space ... The meso-2,6-dichlorophenyl boron-dipyrromethene(BODIPY) derivative 1 was synthesized and characterized by single-crystal X-ray diffraction analysis, 1 H NMR and Esi-HRMS. Compound 1 crystallizes in monoclinic, space group P21/n with a = 8.717(4), b = 20.938(9), c = 12.402(6) ?, β = 98.660(7)°, V = 2237.7(17) ?3, D3 c = 1.333 Mg/cm, F(000) = 936, μ = 0.319 –mm1, Z = 4, the final R = 0.0537 and wR = 0.1556 for 5064 observed reflections with I > 2ζ(I). Its photophysical properties were investigated by fluorescence and UV-Vis spectrum. 1 shows high fluorescence quantum yield in different solvents and poor solvent effect. In addition, compound 1 has high values of initial decomposition temperature(298 ℃). Moreover, cell imaging experiments showed 1 is promising for further bioimaging applications. 展开更多
关键词 BODIPY photo-physical properties cell imaging CRYSTAL structure
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Simulation and design of a heat-integrated double-effect reactive distillation process for propylene glycol methyl ether production 被引量:1
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作者 Ran An Shengxin Chen +5 位作者 Shun Hou Yuting Zhu Chunhu Li Xinbao Zhu Ruixia Liu Weizhong An 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第12期103-114,共12页
A double-effect reactive distillation(DERD)process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy cons... A double-effect reactive distillation(DERD)process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy consumption in the tubular plug-flow reactor.A single-column reactive distillation(RD)process was conducted under optimized operating conditions based on sensitivity analysis as a reference.The results demonstrated that the proposed DERD process is able to achieve more than 95%selectivity of the desired product.After that,a design approach of the DERD process with an objective of the minimum operating cost was proposed to achieve further energy savings in the RD process.The proposed DERD configuration can provide a large energy-savings by totally utilization of the overhead vapor steam in the high-pressure RD column.A comparison of the single-column RD process revealed that the proposed DERD process can reduce the operating cost and the total annual cost of 25.3%and 30.7%,respectively,even though the total capital cost of DERD process is larger than that of the RD process. 展开更多
关键词 Propylene oxide Reactive distillation Heat integration Propylene glycol monomethyl ether Process simulation
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An improved theoretical procedure for the pore-size analysis of activated carbon by gas adsorption 被引量:3
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作者 Guodong Wang Jianchun Jiang +1 位作者 Kang Sun Jianzhong Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第3期551-559,共9页
Amorphous carbon materials play a vital role in adsorbed natural gas(ANG) storage. One of the key issues in the more prevalent use of ANG is the limited adsorption capacity, which is primarily determined by the porosi... Amorphous carbon materials play a vital role in adsorbed natural gas(ANG) storage. One of the key issues in the more prevalent use of ANG is the limited adsorption capacity, which is primarily determined by the porosity and surface characteristics of porous materials. To identify suitable adsorbents, we need a reliable computational tool for pore characterization and, subsequently, quantitative prediction of the adsorption behavior. Within the framework of adsorption integral equation(AIE), the pore-size distribution(PSD) is sensitive to the adopted theoretical models and numerical algorithms through isotherm fitting. In recent years, the classical density functional theory(DFT) has emerged as a common choice to describe adsorption isotherms for AIE kernel construction. However,rarely considered is the accuracy of the mean-field approximation(MFA) commonly used in commercial software. In this work, we calibrate four versions of DFT methods with grand canonical Monte Carlo(GCMC) molecular simulation for the adsorption of CH_4 and CO_2 gas in slit pores at 298 K with the pore width varying from 0.65 to 5.00 nm and pressure from 0.2 to 2.0 MPa. It is found that a weighted-density approximation proposed by Yu(WDA-Yu) is more accurate than MFA and other non-local DFT methods. In combination with the trapezoid discretization of AIE, the WDA-Yu method provides a faithful representation of experimental data, with the accuracy and stability improved by 90.0% and 91.2%, respectively, in comparison with the corresponding results from MFA for fitting CO_2 isotherms. In particular, those distributions in the feature pore width range(FPWR)are proved more representative for the pore-size analysis. The new theoretical procedure for pore characterization has also been tested with the methane adsorption capacity in seven activated carbon samples. 展开更多
关键词 Non-local density functional theory Amorphous porous materials Pore size characterization Gas adsorption Adsorption integral equation
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Synthesis,Crystal Structure and Antitumor Activity of a New Indolequinone Derivative of Ursolic Acid 被引量:1
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作者 郝云 华大威 +3 位作者 苗婷婷 王石发 金晓燕 谷文 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第8期1167-1173,共7页
The title compound(C(37)H(48)BrNO5, 6) was synthesized from ursolic acid and its crystal structure was determined by single-crystal X-ray diffraction analysis. The compound is of orthorhombic system, space group... The title compound(C(37)H(48)BrNO5, 6) was synthesized from ursolic acid and its crystal structure was determined by single-crystal X-ray diffraction analysis. The compound is of orthorhombic system, space group P212121 with a = 16.846(3), b = 18.844(4), c = 11.262(2)A, Z =4, V = 3575.1(13) A^3, Mr = 666.67, Dc = 1.239 Mg/m^3, S = 1.002, μ = 1.190 mm^-1, F(000) = 1408,the final R = 0.0831 and wR = 0.1459 for 2286 observed reflections(I 〉 2σ(I)). The crystal structure is stabilized by two intermolecular hydrogen bonds(N–H(0A)···O(2) and O(1)–H(1A)···O(3)). In the preliminary antitumor assay, the title compound 6 exhibits potent cytotoxic activity against Hep G2 and SMMC-7721 cells with IC50 values of 1.64 ± 0.21 and 1.22 ± 0.13 μM, respectively. 展开更多
关键词 ursolic acid indolequinone crystal structure antitumor activity
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