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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

Numerical modeling of simultaneous hydraulic fracturing in the mode of multi-well pads

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Science China(Technological Sciences) 2017年第2期60卷 232-242页

作者： yao jun zeng QingDong HUANG ZhaoQin SUN Hai ZHANG Lei School of Petroleum Engineering China University of Petroleum (East China) Department of Petroleum Engineering Colorado School of Mines

In order to investigate propagation regularity of hydraulic fractures in the mode of multi-well pads, numerical modeling of simultaneous hydraulic fracturing of multiple wells was conducted. The mathematical model was established coupling rock deformation with fluid flow in the fractures and wellbores. And then the model was solved by displacement discontinuity method coupling with implicit level set method. The implicit method was based on fracture tip asymptotical solution and used to determine fracture growth length. Simulation results showed that when multiple wells were fractured simultaneously, adjacent fractures might propagate towards each other, showing an effect of attraction other than repulsion. Fracture spacing and well spacing had significant influence on the propagation path and geometry of multiple fractures. Furthermore, when multiple wells were fractured simultaneously, stress reversal regions had a large area, and stress reversal regions were distributed not only in the area between fractures but also on the outside of them. The area of stress reversal regions was related to fracture spacing and well spacing. Results indicated that multi-well fracturing induced larger area of stress reversal regions than one-well fracturing, which was beneficial to generating complex fracture network in unconventional reservoirs.

关键词： hydraulic fracturing multi-well pads displacement discontinuity method implicit level set method stress reversal region

Analysis of fracture propagation and shale gas production by intensive volume fracturing

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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1385-1408页

作者： Qingdong zeng Long BO Lijun LIU Xuelong LI Jianmeng SUN Zhaoqin HUANG jun yao College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266580Shandong ProvinceChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China College of Energy Chengdu University of TechnologyChengdu 610059China College of Geoscience China University of Petroleum(East China)Qingdao 266580Shandong ProvinceChina

This paper presents an integrated study from fracture propagation modeling to gas flow modeling and a correlation analysis to explore the key controlling factors of intensive volume *** fracture propagation model takes into account the interaction between hydraulic fracture and natural fracture by means of the displacement discontinuity method(DDM)and the Picard iterative *** shale gas flow considers multiple transport mechanisms,and the flow in the fracture network is handled by the embedded discrete fracture model(EDFM).A series of numerical simulations are conducted to analyze the effects of the cluster number,stage spacing,stress difference coefficient,and natural fracture distribution on the stimulated fracture area,fractal dimension,and cumulative gas production,and their correlation coefficients are *** results show that the most influential factors to the stimulated fracture area are the stress difference ratio,stage spacing,and natural fracture density,while those to the cumulative gas production are the stress difference ratio,natural fracture density,and cluster *** indicates that the stress condition dominates the gas production,and employing intensive volume fracturing(by properly increasing the cluster number)is beneficial for improving the final cumulative gas production.

关键词： fracture network propagation shale gas fow intensive volume fracturing displacement discontinuity method(DDM) embedded discrete fracture model(EDFM)

Postsynthetic acid modification of amino-tagged metal-organic frameworks:Structure-function relationship for catalytic 5-hydroxymethylfurfural synthesis

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Chinese Journal of Chemical Engineering 2022年第9期35卷 245-252页

作者： yao Zhong Cuiying Huang Lijie Li Qiang Deng jun Wang Zheling zeng Shuguang Deng Key Laboratory of Poyang Lake Environment and Resource Utilization(Nanchang University)of the Ministry of Education School of ResourceEnvironmental and Chemical EngineeringNanchang UniversityNanchang 330031China School for Engineering of Matter Transport and EnergyArizona State UniversityArizona 85287United States

Developing an efficient and selective catalyst for the dehydration of fructose to 5-hydroxymethylfurfural(HMF)is significant for biomass ***,a metal-organic framework(MOF)with acidity and strong hydrophobicity is first reported by the condensation of amino-tagged MOFs with mercapto carboxylic acids and subsequent *** hydrophobic acidic MOFs possess acid densities ranging from 0.2-1.0 mmol·g^(-1),H_(2)O contact angles of 114°-125°,and specific surface areas above260 m^(2)·g^(-1).Compared to the methyl sulfo-functionalized MOF,the benzene sulfo-functionalized MOF with a strong hydrophobicity shows much higher activity and selectivity for the conversion of fructose to *** particular,2.99%(mass)UiO-PhSO_(3)H shows the best catalytic performance with a 90.4%HMF yield due to its suitable hydrophobicity and abundant acidic ***,the catalyst shows great stability after recycling for 5 *** work provides an interesting design strategy for the preparation of hydrophobic acidic MOFs and shows the powerful synergistic effect of acidity and hydrophobicity.

关键词： Metal-organic framework 5-Hydroxymethylfurfural Fructose Acidity Hydrophobicity

Optimal decomposition level selection approach in wavelet threshold denoising algorithm for ECG signal

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The Journal of China Universities of Posts and Telecommunications 2023年第4期30卷 86-104页

作者： yao Yindi Yi jun zeng Zhibin Li Xiong Wang Chen Li Yuhang School of Communications and Information Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China School of Microelectronics Xidian UniversityXi'an 710071China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

The effect of electrocardiogram(ECG)signal wavelet denoising depends on the optimal configuration of its control parameters and the selection of the optimal decomposition ***,the existing optimal decomposition level selection scheme has some problems,such as lack of reliable theoretical guidance and insufficient accuracy,which need to be solved *** solve this problem,this paper proposes an optimal decomposition level selection method based on multi-index fusion,which is used to select the optimal decomposition level for wavelet threshold denoising of ECG *** the stage of index selection,in order to overcome the limitation of a single evaluation index,the optimal multi-evaluation index is selected through the joint analysis of the geometric and physical significance of traditional evaluation *** the stage of index fusion,based on the method of weighting the selected multiple indexes by the information entropy weight method and the coefficient of variation method,an optimal decomposition level selection method based on the evaluation index Z is proposed to improve the accuracy of the optimal decomposition level ***,extensive experiments are carried out on the real ECG signal from the Massachusetts Institute of Technology-Beth Israel Hospital(MIT-BIH)arrhythmia database and simulated signal to test the performance of the proposed *** experimental results show that the accuracy of this method is superior to other related methods,and it can achieve better denoising effect of ECG signal.

关键词： ECG signal wavelet threshold denoising optimal decomposition level muti-index fusion

Polypropylene crisper and 1-MCP delay the softening,lignification and transcription levels of related enzyme genes of golden needle mushrooms(Flammulina velutipes)

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Journal of Integrative Agriculture 2022年第1期21卷 249-260页

作者： WANG Wen-jun LI yao LI Fu-hua zeng Kai-fang MING Jian College of Food Science Southwest UniversityChongqing 400715P.R.China Research Center of Food Storage&Logistics Southwest UniversityChongqing 400715P.R.China

The fresh postharvest golden needle mushroom(Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality *** with 1-methylcyclopropene(1-MCP) and polypropylene(PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage. The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes;either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase(PAL), cinnamyl alcohol dehydrogenase(CAD), cellulase(Cx), pectin methylesterase(PME) and polygalacturonase(PG). Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best. The results of transmission electron microscopy(TEM) and scanning electron microscopy(SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture. The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes. In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.

关键词： Flammulina velutipes polypropylene crisper 1-MCP softening and lignification transcription levels

Numerical Simulation of Water Entry of Wedges in Waves Using A CIPBased Model

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China Ocean Engineering 2021年第1期35卷 48-60页

作者： HU Zi-jun ZHAO Xi-zeng LI Meng-yu ZHAO Xin yao Wen-wei SHAO Jie Zhejiang Institute of Hydraulic and Estuary Hangzhou 310020China Ocean College Zhejiang UniversityZhoushan 316021China

In this study,the water entry of wedges in regular waves is numerically investigated by a two-dimensional in-house numerical *** numerical model based on the viscous Navier−Stokes(N−S)equations employs a high-order different method—the constrained interpolation profile(CIP)method to discretize the convection term.A Volume of Fluid(VOF)-type method,the tangent of hyperbola for interface capturing/slope weighting(THINC/SW)is employed to capture the free surface/interface,and an immersed boundary method is adopted to treat the motion of *** momentum source function derived from the Boussinesq equation is applied as an internal wavemaker to generate regular *** accuracy of the numerical model is validated in comparison with experimental results in the *** results of water entry in waves are provided in terms of the impact force of wedge,velocity and pressure distributions of *** attention is paid to the effects of wave parameters and the position of wedge impacting the water *** is found that the existence of waves significantly influences the velocity and pressure field of fluid and impact force on the wedges.

关键词： Water entry water wave wedge internal wave maker CIP method VOF method

Functionalized metal-organic frameworks with strong acidity and hydrophobicity as an efficient catalyst for the production of 5-hydroxymethylfurfural

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Chinese Journal of Chemical Engineering 2021年第5期34卷 167-174页

作者： Huan Li yao Zhong Luxi Wang Qiang Deng jun Wang Zheling zeng Xinxiang Cao Shuguang Deng Key Laboratory of Poyang Lake Environment and Resource Utilization(Nanchang University)of the Ministry of Education School of ResourceEnvironmental and ChemicalEngineeringNanchang UniversityNanchang 330031China Laboratory for Development&Application of Cold Plasma Technology College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471022China School for Engineering of Matter Transport and EnergyArizona State University551 E.Tyler MallTempeAZ 85287United States

In the dehydration of fructose to 5-hydroxymethyl furfural(HMF),in situ produced water weakens the acid strength of the catalyst and causes the rehydration of HMF,causing unsatisfactory catalytic activity and *** this work,a class of benzenesulfonic acid-grafted metal-organic frameworks with strong acidity and hydrophobicity is obtained by the direct sulfonation method using 4-chlorobenzenesulfonic acid as sulfonating *** resultant MOFs have a specific surface area of greater than 250 m^(2)·g^(-1),acid density above 1.0 mmol·g^(-1),and water contact angle up to 129°.The hydrophobic MOF-PhSO_(3)H exhibits both higher catalytic activity and selectivity than MOF-SO_(3)H in the HMF synthesis due to its better hydrophobicity and ***,the catalyst has a high recycled *** last,fructose is completely converted,and 98.0%yield of HMF is obtained under 120℃ in a DMSO solvent *** successful preparation of the hydrophobic acidic MOF provides a novel hydrophobic catalyst for the synthesis of HMF.

关键词： Catalysis Catalyst Biomass Metal-organic framework Fructose 5-Hydroxymethylfurfural

Investigation of erosion behavior of 304 stainless steel under solid–liquid jet flow impinging at 30°

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Petroleum Science 2020年第4期17卷 1135-1150页

作者： Yan-Lin Zhao Chun-Yan Tang jun yao Zi-Hua zeng Shi-Gang Dong Beijing Key Laboratory of Process Fluid Filtration and Separation College of Mechanical and Transportation EngineeringChina University of Petroleum-BeijingBeijing 102249People’s Republic of China College of Energy Xiamen UniversityXiamen 361005People’s Republic of China

This work carried out liquid-solid two-phase jet experiments and simulations to study the erosion behavior of 304 stainless steel at 30° *** single-phase impinging jet was simulated using dense grid by one-way coupling of solid phase due to its dilute *** simulation results agreed well with *** was found that after impinging particle attrition occurred and particles became round with decreasing length-ratio and particle breakage occurred along the "long" *** experiment and simulations found that the erosion generated on the sample could be divided into three regions that were nominated as stagnant region,cutting transition region and wall jet *** particle-wall impacts were found to occur in the cutting transition region and the wall jet *** the cutting transition region,holes and lip-shaped hogbacks were generated in the same direction as the flow *** the wall jet region,furrows and grooves were *** averaged grooves depth tended to become constant with the progress of impinging and reach the steady state of erosion in the *** addition,it was found that impinging effect increased erosion and anti-wear rate.

关键词： Solid–liquid flow Impinging jet Erosion Experiment Numerical simulation