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学者姓名:鲍晓军
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We report a facile yet effective strategy to prepare hierarchical Beta zeolite with high molecular transport effectivity in catalysis. Alkaline etching involves preferential desilication from Beta framework and collapse of microporosity. The preferential desilication from outer rim of Beta stacking faults enlarged intercrystallite mesopores, while the collapse of microporosity created cylindroid-like intracrystalline mesopore. Part of Altet with lower stability was removed during alkaline etching, leading to a decrease in acid sites density. Alkaline etching of Beta zeolite with 0.2 mol/L NaOH solution greatly improved n -hexane isomerization activity over Ptbased catalysts. The maximum yield of isohexane and dibranched isomers increased by 6.2 % and 38.6 %, respectively. The enlargement of intercrystallite mesopores and the generation of intracrystalline mesopores of Beta zeolite lowered apparent activation energy of reaction. The apparent diffusivities measurements further revealed that Pt/Beta-0.2 M showed much lower transport limitation than Pt/Beta-parent. Our findings provide a promising catalyst for industrial alkane isomerization.
Keyword :
Alkaline etching Alkaline etching Alkane isomerization Alkane isomerization Dibranched isomers Dibranched isomers Diffusion barrier Diffusion barrier Mesoporous Beta zeolite Mesoporous Beta zeolite
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GB/T 7714 | Wang, Pengzhao , Chen, Tingting , Qiu, Zihui et al. Pt-promoted mesoporous Beta zeolite catalysts for n-Hexane isomerization with enhanced selectivity to dibranched isomers [J]. | FUEL , 2024 , 368 . |
MLA | Wang, Pengzhao et al. "Pt-promoted mesoporous Beta zeolite catalysts for n-Hexane isomerization with enhanced selectivity to dibranched isomers" . | FUEL 368 (2024) . |
APA | Wang, Pengzhao , Chen, Tingting , Qiu, Zihui , Yao, Wenjun , Liu, Pengpeng , Zhang, Yongze et al. Pt-promoted mesoporous Beta zeolite catalysts for n-Hexane isomerization with enhanced selectivity to dibranched isomers . | FUEL , 2024 , 368 . |
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Cu/ZnO/Al2O3 catalysts have been widely applied as industrial catalysts for methanol synthesis from syngas, but suffers low activity for CO2 hydrogenation to methanol. This study establishes highly active Cu catalysts through modulation of the composite of Al2O3 and ZrO2 in Cu/ZnO-based catalysts. The composition of Al2O3 and ZrO2 impacts the Cu dispersion, exposed surface area of Cu, the Cu0/(Cu0+Cu+) ratio and surface basicity. An appropriate content of Al2O3 and ZrO2 presents the higher Cu surface area, desirable ratio of Cu0/(Cu0+Cu+) and moderate -strong basic sites for effective CO2 adsorption/activation, giving rise to higher space-time yield of methanol (up to 648 gCH3OH & sdot;kgcat - 1 & sdot;h- 1) than the commercial Cu catalyst. STY of methanol can be correlated with Cu surface area and Cu0/(Cu0+Cu+) ratio under the investigated conditions. The mechanistic analysis demonstrates that surface formate and methoxy species are the major intermediates. The methanol formation principally follows the formate-methoxy intermediate pathway.
Keyword :
CO2 hydrogenation CO2 hydrogenation Cu Cu Methanol synthesis Methanol synthesis Oxide promoter Oxide promoter
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GB/T 7714 | Wang, Jianwen , Song, Yihui , Li, Jing et al. Modulation of Al2O3 and ZrO2 composite in Cu/ZnO-based catalysts with enhanced performance for CO2 hydrogenation to methanol [J]. | APPLIED CATALYSIS A-GENERAL , 2024 , 674 . |
MLA | Wang, Jianwen et al. "Modulation of Al2O3 and ZrO2 composite in Cu/ZnO-based catalysts with enhanced performance for CO2 hydrogenation to methanol" . | APPLIED CATALYSIS A-GENERAL 674 (2024) . |
APA | Wang, Jianwen , Song, Yihui , Li, Jing , Liu, Fengdong , Wang, Jiajing , Lv, Jing et al. Modulation of Al2O3 and ZrO2 composite in Cu/ZnO-based catalysts with enhanced performance for CO2 hydrogenation to methanol . | APPLIED CATALYSIS A-GENERAL , 2024 , 674 . |
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Synthesizing zeolites, which are important materials used in the petroleum and chemical industries, from natural aluminosilicate minerals has been qualitatively recognized as a greener approach compared to that from traditional Si- and Al-containing chemicals; however, studies on the quantitative environmental impacts are still lacking. Herein, life cycle assessment (LCA) and green metrics (atom economy and environmental factor) were employed to comparatively assess the life cycle environmental impacts of zeolites synthesized from chemicals and natural minerals at the industrial scale. The values of seven LCA impact categories and sensitivity analysis between them were thoroughly compared. The results showed that, for each category, the synthesis from natural minerals has lower environmental impacts to varying degrees than that from chemicals. Further efficiency analysis of zeolite manufacturing technologies by green metrics indicated that the synthesis from natural minerals outperforms that from chemicals in terms of the resource utilization rate. The quantitative results indicate that significant benefits stem from the replacement of raw materials from chemicals to natural minerals. This work may provide a basis for the future selection and upgrade of zeolite production processes. Life cycle assessment and green metrics were used to comparatively assess the synthesis of zeolites from natural minerals and chemicals in which the former exhibits a better balance between efficiency and environmental impacts than the latter.
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GB/T 7714 | Chen, Xiaoling , Xiao, Guoxi , Li, Tiesen et al. Comparative environmental assessment of zeolites synthesized from chemicals and natural minerals [J]. | GREEN CHEMISTRY , 2024 , 26 (9) : 5273-5283 . |
MLA | Chen, Xiaoling et al. "Comparative environmental assessment of zeolites synthesized from chemicals and natural minerals" . | GREEN CHEMISTRY 26 . 9 (2024) : 5273-5283 . |
APA | Chen, Xiaoling , Xiao, Guoxi , Li, Tiesen , Wang, Chan , Cui, Qingyan , Bao, Xiaojun et al. Comparative environmental assessment of zeolites synthesized from chemicals and natural minerals . | GREEN CHEMISTRY , 2024 , 26 (9) , 5273-5283 . |
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Carbon adsorbents have been widely used to remove indoor volatile organic compounds (VOCs), however, the proliferation of bacteria on the carbon adsorbents may deteriorate the indoor air quality and thus pose a serious threat to human health. Herein, we report the synthesis of antibacterial porous carbon spheres (carbonized aminophenol-formaldehyde resin, CAF) with well-dispersed Cu species via an in situ incorporation of Cu2+ during the polymerization of 3-aminophenol-formaldehyde resin followed by a thermal carbonization and reduction process. Compared with CAF, the Cu/CAF-x nanocomposites with Cu loading show a much higher specific surface area (>700 m2 g−1 vs. 569 m2 g−1 for CAF). In addition, the pore size of Cu/CAF-x is ranging from 0.7 to 1.68 nm, which is exactly conducive to adsorb the toluene molecules. As a result, the toluene adsorption capacity is improved from 123.50 mg g−1 for CAF to >170 mg g−1 for Cu/CAF-x. More importantly, such adsorbents possess excellent antibacterial performance, the Cu/CAF-10 (10 wt% of Cu loading) with a concentration of 50 μg mL−1 can completely kill the E. coli within 30 min. Our work paves the way to the development of bifunctional adsorbents with both efficient VOCs adsorption and excellent antibacterial performance. © 2023
Keyword :
Adsorption Adsorption Air quality Air quality Carbonization Carbonization Copper compounds Copper compounds Escherichia coli Escherichia coli Formaldehyde Formaldehyde Health risks Health risks Indoor air pollution Indoor air pollution Pore size Pore size Porous materials Porous materials Toluene Toluene Volatile organic compounds Volatile organic compounds
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GB/T 7714 | Zhang, Hongwei , Wu, Guanghui , Liu, Qunhong et al. Bifunctional Cu-incorporated carbon nanospheres via in-situ complexation strategy as efficient toluene adsorbents and antibacterial agents [J]. | Chemosphere , 2024 , 349 . |
MLA | Zhang, Hongwei et al. "Bifunctional Cu-incorporated carbon nanospheres via in-situ complexation strategy as efficient toluene adsorbents and antibacterial agents" . | Chemosphere 349 (2024) . |
APA | Zhang, Hongwei , Wu, Guanghui , Liu, Qunhong , Liu, Zhichen , Yang, Qin , Cui, Qingyan et al. Bifunctional Cu-incorporated carbon nanospheres via in-situ complexation strategy as efficient toluene adsorbents and antibacterial agents . | Chemosphere , 2024 , 349 . |
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Propylene is the second most important chemicals in the petrochemical industry. Propane dehydrogenation as the on -purpose propylene production route, has attracted much attentions due to great success in the exploitation of shale gas. Recently, Pt@zeolite is proven to the most promising catalyst for propane dehydrogenation, because Pt clusters encapsulated in zeolite channel show high resistance to Pt particles sintering. However, the micropore of zeolite imposes severe diffusion limitation of propylene, and thus the coke formation easily takes place which leads to a fast deactivation. Herein, we report efficient Pt/Zn-MFIhierarchical catalysts for PDH with auxiliary mesopore for accelerating mass transfer, and these Pt/Zn-MFIhierarchical exhibit not only high thermal stability but also excellent resistance to coking. The Pt/Zn-MFIhierarchical catalyst is obtained by an introduction of Pt species into the hierarchically porous Zn-MFI that is prepared from one-step hydrothermal synthesis. The formed Pt-Zn clusters are exclusively located in the micropore of MFIhierarchical, and the migrating of Pt-Zn clusters is largely prevented under the harsh reaction conditions. Mesopores in MFIhierarchical greatly enhances the diffusion rate of propylene, which significantly alleviates the coke formation arising from polymerization of propylene. The most efficient Pt/Zn-MFI-120hierarchical catalyst delivers propane conversion of around 46 % and propylene selectivity of above 98 %. This catalyst undergoes a slow loss of activity with a deactivation rate kd of as low as 0.005 h-1, and its catalytic performance can be fully restored via a simple calcination.
Keyword :
Coking-resistance Coking-resistance Hierarchical zeolite Hierarchical zeolite Propane dehydrogenation Propane dehydrogenation Propylene production Propylene production Pt-Zn clusters Pt-Zn clusters Sintering-resistance Sintering-resistance
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GB/T 7714 | Lu, Jinyang , Xu, Zhikang , Yue, Yuanyuan et al. Pt-Zn clusters encapsulated in hierarchical MFI zeolite for efficient propane dehydrogenation [J]. | CHEMICAL ENGINEERING JOURNAL , 2024 , 484 . |
MLA | Lu, Jinyang et al. "Pt-Zn clusters encapsulated in hierarchical MFI zeolite for efficient propane dehydrogenation" . | CHEMICAL ENGINEERING JOURNAL 484 (2024) . |
APA | Lu, Jinyang , Xu, Zhikang , Yue, Yuanyuan , Bao, Xiaojun , Lin, Minggui , Zhu, Haibo . Pt-Zn clusters encapsulated in hierarchical MFI zeolite for efficient propane dehydrogenation . | CHEMICAL ENGINEERING JOURNAL , 2024 , 484 . |
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热催化CO2加氢制甲醇具有显著的减碳效应,能够有效储存可再生能源,具有广阔的工业应用前景.介绍了 CO2加氢制甲醇的反应网络及其热力学挑战,并概述了其工艺流程、国内外工业应用情况,系统综述了近年来不同活性组分催化剂的研究进展,从催化剂的制备方式、活性位点、反应机理及动力学等方面阐述Cu基催化剂、贵金属催化剂、氧化物催化剂以及其他新型催化剂存在的问题和优势.重点阐述Cu基催化剂的构效关系,包括其活性组分结构、载体性质和助剂对催化活性和甲醇选择性的影响,并展望CO2加氢制甲醇催化剂的未来发展方向.
Keyword :
CO2 CO2 催化剂 催化剂 加氢 加氢 反应动力学 反应动力学 反应机理 反应机理 甲醇 甲醇
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GB/T 7714 | 王佳静 , 王建文 , 李茂帅 et al. CO2催化加氢合成甲醇研究进展 [J]. | 石油炼制与化工 , 2024 , 55 (2) : 75-83 . |
MLA | 王佳静 et al. "CO2催化加氢合成甲醇研究进展" . | 石油炼制与化工 55 . 2 (2024) : 75-83 . |
APA | 王佳静 , 王建文 , 李茂帅 , 宋奕慧 , 王石维 , 吕静 et al. CO2催化加氢合成甲醇研究进展 . | 石油炼制与化工 , 2024 , 55 (2) , 75-83 . |
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Defect-rich Pd/TiO2 catalysts are intensively adopted in heterogeneous hydrogenation reactions; however, the complexity of the defect structure makes it difficult to precisely identify which Pd-defect combination dominates the catalytic activity. Herein, defective TiO2 nanoflakes with tunable ratios of Vo to Ti3+ defects were synthesized and used to construct Pd-Vo and Pd-Ti3+ active sites after loading Pd to investigate the role of defects in regulating the structural and catalytic properties of defective Pd/TiO2 catalysts. Combining the experimental results and theoretical calculations, we reveal that both Vo and Ti3+ defects act as the electron donors for Pd and induce the strong metal-support interaction. When compared to the Vo defect, the Ti3+ defect behaves more significantly and donates more electrons, causing the Pd species on the catalysts to be better dispersed and more rich in electrons. These unique features endow the Pd-Ti3+ active centers with enhanced adsorption-activation ability toward C & boxH;C and H-2 as well as reduced energy barrier of the rate-limiting step, thus improving the intrinsic activity. The Pd-Ti3+ site manifests a high turnover frequency of 348 h(-1) and hydrogenation degree of 97% for hydrogenation of C & boxH;C in styrene-butadiene-styrene, which significantly outperforms the Pd-Vo site (254 h(-1) and 78%) and Pd nanoparticle (217 h(-1) and 53%). This work provides deep insight into the role of defects in regulating the properties of metal active sites, which can be used to guide the development of high-performance Pd/TiO2 catalysts for versatile applications.
Keyword :
defective TiO2 defective TiO2 electronic structure electronic structure hydrogenation hydrogenation styrene-butadiene-styrene styrene-butadiene-styrene Ti3+-Pd site Ti3+-Pd site Vo-Pd site Vo-Pd site
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GB/T 7714 | Wang, Shidong , Ge, Bingqing , Yang, Zongxuan et al. Construction of Highly Active Pd-Ti3+ Sites in Defective Pd/TiO2 Catalysts for Efficient Hydrogenation of Styrene-Butadiene-Styrene [J]. | ACS CATALYSIS , 2024 , 14 (3) : 1432-1442 . |
MLA | Wang, Shidong et al. "Construction of Highly Active Pd-Ti3+ Sites in Defective Pd/TiO2 Catalysts for Efficient Hydrogenation of Styrene-Butadiene-Styrene" . | ACS CATALYSIS 14 . 3 (2024) : 1432-1442 . |
APA | Wang, Shidong , Ge, Bingqing , Yang, Zongxuan , Zhang, Hongwei , Yang, Qin , Hu, Cejun et al. Construction of Highly Active Pd-Ti3+ Sites in Defective Pd/TiO2 Catalysts for Efficient Hydrogenation of Styrene-Butadiene-Styrene . | ACS CATALYSIS , 2024 , 14 (3) , 1432-1442 . |
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Electrocatalytic oxidation as a promising route to produce value-added products from biomass-derived organics has received increasing attention in recent years. However, the efficient conversion of concentrated feedstock solutions with high selectivity and Faradaic efficiency (FE) remains challenging. Herein, we report a cation-defective Ni-based electrocatalyst derived from the surface reconstruction of the NiCo Prussian blue analogue (NiCo PBA) in alkaline media for the efficient oxidation of biomass-derived organics in a high concentration solution. Taking 5-hydroxymethylfurfural (HMF) as an example, the NiCo PBA can deliver a satisfactory catalytic performance in terms of high HMF conversion (97%), selectivity to 2,5-furandicarboxylic acid (98%), and FE (100%), even at a concentration as high as 100 mM. Theoretical calculations suggest that the cation defects not only promote the fast conversion of Ni(OH)(2) to electrochemically active NiOOH under anodic potential but also enhance the adsorption of HMF onto the active sites and accelerate the spontaneous chemical oxidation. This study provides deep insights into the structural evolution of PBA-based catalysts and reveals the pivotal factor that affects the performance of electrocatalytic oxidation, paving the way to further develop advanced electrocatalysts for efficient oxidation reactions with a high concentration.
Keyword :
biomass upgrade biomass upgrade cation defects cation defects electrooxidation electrooxidation operandoRaman spectroscopies operandoRaman spectroscopies Prussian blue analogues catalysts Prussian blue analogues catalysts
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GB/T 7714 | Zhang, Hongwei , Yang, Qin , Luo, Shuting et al. On the Activity and Selectivity of 5-Hydroxymethylfurfural Electrocatalytic Oxidation over Cation-Defective Nickel Hydroxides [J]. | ACS CATALYSIS , 2024 , 14 (12) : 9565-9574 . |
MLA | Zhang, Hongwei et al. "On the Activity and Selectivity of 5-Hydroxymethylfurfural Electrocatalytic Oxidation over Cation-Defective Nickel Hydroxides" . | ACS CATALYSIS 14 . 12 (2024) : 9565-9574 . |
APA | Zhang, Hongwei , Yang, Qin , Luo, Shuting , Liu, Zhichen , Huang, Jinming , Zheng, Yun et al. On the Activity and Selectivity of 5-Hydroxymethylfurfural Electrocatalytic Oxidation over Cation-Defective Nickel Hydroxides . | ACS CATALYSIS , 2024 , 14 (12) , 9565-9574 . |
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Water electrolysis for hydrogen production holds great promise as an energy conversion technology. The electrolysis process contains two necessary electrocatalytic reactions, one is the hydrogen evolution reaction (HER) at the cathode, and the other is the oxygen evolution reaction (OER) at the anode. In general, the kinetics of OER is much slower than that of HER, dominating the overall of performance electrolysis. As identified, the slow kinetics of catalytic OER is mainly resulted from multiple electron transfer steps, and the catalysts often undergo compositional, structural, and electronic changes during operation, leading to complicated dynamic reaction mechanisms which have not been fully understood. Obviously, this challenge presents formidable obstacles to the development of highly efficient OER electrocatalysts. To address the issue, it is crucial to unravel the origins of intrinsic OER activity and stability and elucidate the catalytic mechanisms across diverse catalyst materials. In this context, in-situ/operando characterization techniques would play a pivotal role in understanding the catalytic reaction mechanisms by enabling real-time monitoring of catalyst structures under operational conditions. These techniques can facilitate the identification of active sites for OER and provide essential insights into the types and quantities of key reaction intermediates. This comprehensive review explores various catalyst design and synthesis strategies aimed at enhancing the intrinsic OER activity and stability of catalysts and examines the application of advanced in-situ/operando techniques for probing catalyst mechanisms during the OER process. Furthermore, the imperative need for developing innovative in-situ/operando techniques, theoretical artificial intelligence and machine learning and conducting theoretical research to better understand catalyst structural evolution under conditions closely resembling practical OER working states is also deeply discussed. Those efforts should be able to lay the foundation for the improved fabrication of practical OER catalysts.
Keyword :
Electrocatalysts Electrocatalysts In-situ techniques In-situ techniques Oxygen evolution reaction Oxygen evolution reaction Reaction mechanism Reaction mechanism
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GB/T 7714 | Hu, Cejun , Hu, Yanfang , Zhang, Bowen et al. Advanced Catalyst Design Strategies and In-Situ Characterization Techniques for Enhancing Electrocatalytic Activity and Stability of Oxygen Evolution Reaction [J]. | ELECTROCHEMICAL ENERGY REVIEWS , 2024 , 7 (1) . |
MLA | Hu, Cejun et al. "Advanced Catalyst Design Strategies and In-Situ Characterization Techniques for Enhancing Electrocatalytic Activity and Stability of Oxygen Evolution Reaction" . | ELECTROCHEMICAL ENERGY REVIEWS 7 . 1 (2024) . |
APA | Hu, Cejun , Hu, Yanfang , Zhang, Bowen , Zhang, Hongwei , Bao, Xiaojun , Zhang, Jiujun et al. Advanced Catalyst Design Strategies and In-Situ Characterization Techniques for Enhancing Electrocatalytic Activity and Stability of Oxygen Evolution Reaction . | ELECTROCHEMICAL ENERGY REVIEWS , 2024 , 7 (1) . |
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In recent years, studies focusing on the conversion of renewable lignin-derived oxygenates (LDOs) have emphasized their potential as alternatives to fossil-based products. However, LDOs, existing as complex aromatic mixtures with diverse oxygen-containing functional groups, pose a challenge as they cannot be easily separated via distillation for direct utilization. A promising solution to this challenge lies in the efficient removal of oxygen-containing functional groups from LDOs through hydrodeoxygenation (HDO), aiming to yield biomass products with singular components. However, the high dissociation energy of the carbon–oxygen bond, coupled with its similarity to the hydrogenation energy of the benzene ring, creates a competition between deoxygenation and benzene ring hydrogenation. Considering hydrogen consumption and lignin properties, the preference is directed towards generating aromatic hydrocarbons rather than saturated components. Thus, the goal is to selectively remove oxygen-containing functional groups while preserving the benzene ring structure. Studies on LDOs conversion have indicated that the design of active components and optimization of reaction conditions play pivotal roles in achieving selective deoxygenation, but a summary of the correlation between these factors and the reaction mechanism is lacking. This review addresses this gap in knowledge by firstly summarizing the various reaction pathways for HDO of LDOs. It explores the impact of catalyst design strategies, including morphology modulation, elemental doping, and surface modification, on the adsorption–desorption dynamics between reactants and catalysts. Secondly, we delve into the application of advanced techniques such as spectroscopic techniques and computational modeling, aiding in uncovering the true active sites in HDO reactions and understanding the interaction of reactive reactants with catalyst surface-interfaces. Additionally, fundamental insights into selective deoxygenation obtained through these techniques are highlighted. Finally, we outline the challenges that lie ahead in the design of highly active and selective HDO catalysts. These challenges include the development of detection tools for reactive species with high activity at low concentrations, the study of reaction medium–catalyst interactions, and the development of theoretical models that more closely approximate real reaction situations. Addressing these challenges will pave the way for the development of efficient and selective HDO catalysts, thus advancing the field of renewable LDOs conversion. © 2024 Institute of Process Engineering, Chinese Academy of Sciences
Keyword :
Catalyst design Catalyst design Hydrodeoxygenation Hydrodeoxygenation Lignin-derived oxygenates Lignin-derived oxygenates Targeted deoxidation Targeted deoxidation Techniques and theoretical calculation Techniques and theoretical calculation
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GB/T 7714 | Wu, X. , Zhang, H. , Hu, C. et al. Advances in enhancing hydrodeoxygenation selectivity of lignin-derived oxygenates: From synthetic strategies to fundamental techniques [J]. | Green Energy and Environment , 2024 . |
MLA | Wu, X. et al. "Advances in enhancing hydrodeoxygenation selectivity of lignin-derived oxygenates: From synthetic strategies to fundamental techniques" . | Green Energy and Environment (2024) . |
APA | Wu, X. , Zhang, H. , Hu, C. , Bao, X. , Yuan, P. . Advances in enhancing hydrodeoxygenation selectivity of lignin-derived oxygenates: From synthetic strategies to fundamental techniques . | Green Energy and Environment , 2024 . |
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