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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01期 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.

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OPTIMIZING DESIGN OF MECHANICAL SELF-CENTERING DEVICE FOR SUSPENSION HEIGHT

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Chinese Journal of Mechanical Engineering 2008年第6期21卷 69-75页

作者： cao min ZHANG Yongchao YU Fan School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

Firstly, in view of the respective defects of existing self-centering devices for vehicle suspension height, the design scheme of the proposed mechanical self-centering device for suspension height is described. Taking the rear suspension of a certain light bus as a research example, the structures and parameters of the novel device are designed and ascertained. Then, the road excitation models, the performance evaluation indexes and the half-vehicle model are built, the simulation outputs of time and frequency domain are obtained with the road excitations of random and pulse by using MATLAB/Simulink software. So the main characteristics of the self-centering suspension are presented preliminarily. Finally, a multi-objective parameter design optimization model for the self-centering device is built by weighted sum approach, and optimal solution is obtained by adopting complex approach. The relevant choosing-type parameters for self-centering device components are deduced by using discrete variable optimal method, and the optimal results are verified and analyzed. So the performance potentials of the self-centering device are exerted fully in condition of ensuring overall suspension performances.

关键词： Suspension height Self-centering Vehicle height adjustment Optimizing design Multi-objective optimization

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Static and dynamic evolution of CO adsorption onγ-U(100)surface with different levels of Mo doping using DFT and AIMD calculations

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Nuclear Science and Techniques 2023年第9期34卷 142-154页

作者： jun-Wei Li Wei-min Jia Chong Liu Sha-Sha Lv Jin-Tao Wang Zheng-cao Li Key Lab of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Xi’an Research Institute of High-Technology Xi’an 710025China Key Laboratory of Beam Technology(MOE) College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China

Alloys of uranium and molybdenum are considered as the future of nuclear fuel and defense ***,surface corrosion is a fundamental problem in practical applications and *** this study,the static and dynamic evolution of carbon monoxide(CO)adsorption and dissociation onγ-U(100)surface with different Mo doping levels was investigated based on density functional theory and ab initio molecular *** the static calculation phase,parameters,such as adsorption energy,configuration,and Bader charge,were evaluated at all adsorption ***,the time-dependent behavior of CO molecule adsorption were investigated at the most favorable *** minimum energy paths for CO molecu-lar dissociation and atom migration were investigated using the transition state search *** results demonstrated that the CO on the uranium surface mainly manifests as chemical adsorption before dissociation of the CO *** CO molecule exhibited a tendency to rotate and tilt upright ***,it is difficult for CO adsorption on the surface in one of the configurations with CO molecule in vertical direction but oxygen(O)is closer to the *** charge illustrates that the charge transfers from slab atoms to the 2π*antibonding orbital of CO molecule and particularly occurs in carbon(C)*** time is less than 100 fs for the adsorptions that forms embryos with tilt upright in dynamics *** density of states elucidates that the overlapping hybridization of C and O 2p orbitals is mainly formed via the d orbitals of uranium and molybdenum(Mo)atoms in the dissociation and re-adsorption of CO *** conclusion,Mo doping of the surface can decelerate the adsorption and dissociation of CO molecules.A Mo-doped surface,created through ion injection,enhanced the resistance to uranium-induced surface corrosion.

关键词： Adsorption and dissociation Uranium CO molecule Density functional theory Ab initio molecular dynamics

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A Performance Driven Lot Merging Method with Closed Loop Optimization for Semiconductor Wafer Fabrication

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Chinese Journal of Electronics 2017年第5期26卷 912-918页

作者： cao Zhengcai HUANG Zhexiao LIU min College of Information Science and Technology Beijing University of Chemical Technology Symbolic Computation and Knowledge Engineering of ministry of Education Jilin University Department of Automation Tsinghua University

This paper deals with lot merging problem in semiconductor wafer fabrication *** is the possibility to merge two or more partial lots into single lot if their subsequent process routes are the same,an improved lot merging method is presented by grouping lots belonging to different *** on job information extracted from the buffers,several bin packing and knapsack solving algorithms are used to determine which lots should be *** iterative improvement procedure is introduced for optimizing merging strategy through a heuristic algorithm with resetting the ready time of critical *** closed loop structure with global revision factor is built for minimizing the impact of uncertain events while balancing the different orders processing *** to a simulation semiconductor manufacturing fab,the proposed algorithm can reduce cycle time and tardiness compared with other methods currently.

关键词： Semiconductor wafer fabrication Lot merging Simulation Bin packing

Stable 4.5 V LiCoO_(2)cathode material enabled by surface manganese oxides nanoshell

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Nano Research 2023年第2期16卷 2480-2485页

作者： jun Wang Si-Dong Zhang Si-Jie Guo Si-Qi Lu Yan-Song Xu Jin-Yang Li An-min cao Li-jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing 100190China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Charging the LiCoO_(2)(LCO)cathode to a higher voltage,for example 4.5 V compared to the commonly used 4.2 V,is now intensively pursued so as to achieve a higher specific ***,it suffers severe surface structural degradation and detrimental interfacial side reactions between cathode and electrolyte,which lead to the fast capacity fading during long-term ***,a surface coating strategy was developed for the protection of 4.5 V LCO by constructing a manganese oxides(MOs)nanoshell around LCO particles,which was achieved through a solution-based coating process with success in controlling the growth kinetics of the coating *** found that the introduction of the MOs nanoshell is highly effective in alleviating the organic electrolyte decomposition at the cathode surface,thus ensuring a much more stable LiF-rich cathode-electrolyte interface and an obvious lower interfacial resistance during electrochemical ***,this protection layer can effectively improve the structural stability of the cathode by hindering the cracks formation and structural degradation of LCO ***,the MOs modified LCO exhibited excellent rate performance and a high discharge capacity retention of 81.5%after 100 cycles at 1 C compared with the untreated LCO(55.2%),as well as the improved thermal stability and cyclability at the elevated *** is expected that this discovery and fundamental understanding of the surface chemistry regulation strategy provide promising insights into improving the reversibility and stability of LCO cathode at the cut-off voltage of 4.5 V.

关键词： lithium-ion battery 4.5 V LiCoO_(2) manganese oxides surface coating interfacial stability regulation

An unprecedented dumbbell-shaped pentadeca-nuclear W-Er heterometal cluster stabilizing nanoscale hexameric arsenotungstate aggregate and electrochemical sensing properties of its conductive hybrid film-modified electrode

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Nano Research 2022年第4期15卷 3628-3637页

作者： Dan Wang jun Jiang Meng-Ya cao Sai-Sai Xie Ya-min Li Li-Juan Chen jun-Wei Zhao Guo-Yu Yang Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China MOE Key Laboratory of Cluster Science School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Cluster-based functional materials have made remarkable progress owing to their wonderful structures and distinctive physicochemical performances,one of on-going advancements of which is basically driven by synthetic chemistry of exploring and constructing novel nanosized gigantic polyoxometalate(POM)*** this article,an unprecedented nanoscale hexameric arsenotungstate aggregate Na_(9)K_(16)H_(4)[Er_(0.5)K_(0.5)(H_(2)O)_(7)][Er_(5)W10O_(2)6(H_(2)O)_(14)][B-α-AsW_(9)O_(33)]_(6)·102H_(2)O(1)has been synthesized by the combined synthetic strategy of simultaneously using the arsenotungstate precursor and simple tungstate material in a highly acidic aqueous ***{[Er_(5)W_(10)O_(26)(H_(2)O)_(14)][B-α-AsW_(9)O_(33)]6}31-polyanion in 1 consists of an intriguing dumbbell-shaped pentadeca-nuclear W-Er heterometal{Er_(5)W10O_(2)6(H_(2)O)_(14)}^(23+)cluster connecting six trilacunary[B-α-AsW_(9)O_(33)]^(9-)moieties,which has never been seen ***,through electropolymerization of 1 and pyrrole on the conductive substrate,a thickness-controllable and robust 1-PPY(PPY=polypyrrole)hybrid film was successfully prepared,which represents the first POM-PPY film assembled from high-nuclear lanthanide(Ln)encapsulated POM and PPY *** 1-PPY film-based electrochemical biosensor exhibits a favorable recognition performance for ochratoxin A in multiple *** work not only provides a feasible combined synthetic strategy of the POM precursor and simple tungstate material for constructing complicated multi-Ln-inserted POM aggregates,but also offers a promising electrochemical platform constructed from POM-based conductive films for identifying trace biomolecules in complex environments.

关键词： polyoxometalate lanthanide-inserted arsenotungstate polyoxometalate-based conductive film

Hierarchical representation of on-chip context to reduce reconfiguration time and implementation area for coarse-grained reconfigurable architecture

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Science China(Information Sciences) 2013年第11期56卷 279-298页

作者： WANG YanSheng LIU LeiBo YIN ShouYi ZHU min cao Peng YANG jun WEI Shaojun Institute of Microelectronics Tsinghua University National Laboratory for Information Science and Technology Tsinghua University National ASIC System Engineering Technology Research Center Southeast University

In reconfigurable system,fast reconfiguration and small size of configuration contexts are strongly required to enhance the processing performance and reduce the implementation *** this paper,a hierarchical representation of contexts for CGRA called HCC is proposed to satisfy the above *** HCC,the contexts are constructed in a hierarchical fashion to thoroughly eliminate the repetitive portions of the contexts,not only reducing the overall contexts storage size,but also alleviating the contexts transportation *** fast context-indexing mechanism is proposed in HCC to achieve high configuration speed,since the hierarchically organized contexts can be located and accessed *** has been verified in a reconfigurable processor called REMUS *** to HCC,when implementing H.264 decoding on REMUS HP,76.67%of the overall contexts are reduced compared with the traditional non-hierarchical one;and the configuration speed is averagely 23×increased compared with the latest reported optimized configuration mechanism on Virtex-4 *** HP is implemented on a 48.9 mm2silicon with TSMC 65 nm *** shows that 1920×1088@30 fps could be achieved for H.264 high-profile decoding when exploiting a 200 MHz working *** with the high performance version of XPP,the performance is 181%boosted.

关键词： reconfigurable computing hierarchical configuration context REMUS HP fast reconfiguration context compression

Wood species identification using spectral reflectance feature and optimal illumination radian design

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Journal of Forestry Research 2016年第1期27卷 219-224页

作者： Peng Zhao jun cao Information and Computer Engineering College Northeast Forestry University College of Mechanical and Electronic Engineering Northeast Forestry University

We developed a scheme based on wood surface novel wood recognition spectral features that aimed to solve three problems. First was elimination of noise in some bands of wood spectral reflection curves. Second was improvement of wood feature selection based on analysis of wood spectral data. The wood spectral band is 350-2500 nm, a 2150D vector with a spectral sampling interval of 1 nm. We developed a feature selection proce- dure and a filtering procedure by solving the eigenvalues of the dispersion matrix. Third, we optimized the design for the indoor radian＇s mounting height. We used a genetic algorithm to solve the optimal radian＇s height so that the spectral reflection curves had the best classification infor- mation for wood species. Experiments on fivecommon wood species in northeast China showed overall recogni- tion accuracy 〉95 % at optimal recognition velocity.

关键词： Wood species identification Featureselection Radian Genetic algorithm Spectral analysis

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Convergence Analysis of L-ADMM for Multi-block Linear-Constrained Separable Convex minimization Problem

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Journal of the Operations Research Society of China 2015年第4期3卷 563-579页

作者： jun-Kai Feng Hai-Bin Zhang cao-Zong Cheng Hui-min Pei College of Applied Sciences Beijing University of TechnologyBeijing 100124China

We focus on the convergence analysis of the extended linearized alternating direction method of multipliers(L-ADMM)for solving convex minimization problems with three or more separable blocks in the objective *** convergence analysis of the L-ADMM needs to reduce the multi-block convex minimization problems to two blocks by grouping the ***,there has been no rate of convergence analysis for the *** this paper,we construct a counter example to show the failure of convergence of the extended *** prove the convergence and establish the sublinear convergence rate of the extended L-ADMM under the assumptions that the proximal gradient step sizes are smaller than certain values,and any two coefficient matrices in linear constraints are orthogonal.

关键词： Separable convex minimization Alternating direction method of multipliers Linearization Sublinear convergence