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Chinese Chemical Letters 2022年第5期33卷 2415-2419页

作者： Robert Li-Yuan Bao Lei Shi Kang Fu School of Science Harbin Institute of TechnologyShenzhen 518055China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China

A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was prepared.The developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Crafts reaction, affording the products bearing a trifluoromethylated all-carbon quaternary stereocenter with moderate to excellent yields(up to 99%) and good to excellent enantioselectivies(up to> 99.9% ee). Moreover, a proposed model of chiral pocket revealed that the attack of indole from the Re-face of β-CF_(3)-β-disubstituted nitroalkene was favorable.

关键词： Chiral bisoxazoline ligand Chiral pocket Chiral spiro ligand Friedel-Crafts reaction Trifluoromethylated all-carbon quaternary stereocenter

An automatic docking method for large-scale sections based on real-time pose measuring and assembly deviation control

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Optoelectronics Letters 2023年第11期19卷 686-692页

作者： QIAO Zhifeng fu kang LIU Zhenzhong Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin300384China

Aiming at the problem of poor accuracy consistency of large sections’docking assembly,an automatic docking method using multiple laser trackers to measure the position and posture of the docking sections in real time was proposed.In the solution of the pose of the docking section,real-time pose measurement of the docking section was realized by establishing a global coordinate system and a coordinate fusion method of three or more laser trackers.In the automatic control of the docking process,the real-time communication protocol and the circular negative feedback control strategy of measurement-adjustment-re-measurement are adopted,and the fully-automated docking of large sections is realized.Finally,an experimental verification system was set up,and the docking of the large-scale section reduction models was realized under the requirements of docking accuracy,and the effectiveness of the automatic docking scheme was successfully verified.

关键词： coordinate deviation system

New Sixth-Order Compact Schemes for Poisson/Helmholtz Equations

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Numerical Mathematics(Theory,Methods and Applications) 2023年第2期16卷 393-409页

作者： Kejia Pan Kang Fu Jin Li Hongling Hu Zhilin Li School of Mathematics and Statistics HNP-LAMACentral South UniversityChangsha 410083China MOE-LCSM School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China CRSC&Department of Mathematics North Carolina State UniversityRaleighNC 27695-8205USA

Some new sixth-order compact finite difference schemes for Poisson/Helmholtz equations on rectangular domains in both two-and three-dimensions are developed and analyzed.Different from a few sixth-order compact finite difference schemes in the literature,the finite difference and weight coefficients of the new methods have analytic simple expressions.One of the new ideas is to use a weighted combination of the source term at staggered grid points which is important for grid points near the boundary and avoids partial derivatives of the source term.furthermore,the new compact schemes are exact for 2D and 3D Poisson equations if the solution is a polynomial less than or equal to 6.The coefficient matrices of the new schemes are M-matrices for Helmholtz equations with wave number K≤0,which guarantee the discrete maximum principle and lead to the convergence of the new sixth-order compact schemes.Numerical examples in both 2D and 3D are presented to verify the effectiveness of the proposed schemes.

关键词： Poisson equation Helmholtz equation sixth-order compact scheme maximum principle staggered grid.

Bayesian Estimation and Model Selection for the Spatiotemporal Autoregressive Model with Autoregressive Conditional Heteroscedasticity Errors

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应用数学学报:英文版 2023年第4期39卷 972-989页

作者： Bing SU fu-kang ZHU Ju HUANG Department of Statistics&Actuarial Science University of Hong KongHong Kong 999077China School of Mathematics Jilin UniversityChangchun 130012China National Energy Administration Information Center Beijing 100045China

The spatial and spatiotemporal autoregressive conditional heteroscedasticity(STARCH) models receive increasing attention. In this paper, we introduce a spatiotemporal autoregressive(STAR) model with STARCH errors, which can capture the spatiotemporal dependence in mean and variance simultaneously. The Bayesian estimation and model selection are considered for our model. By Monte Carlo simulations, it is shown that the Bayesian estimator performs better than the corresponding maximum-likelihood estimator, and the Bayesian model selection can select out the true model in most times. Finally, two empirical examples are given to illustrate the superiority of our models in fitting those data.

关键词： autoregressive conditional heteroscedasticity model Bayesian estimation model selection spatial ARCH model spatial panel model spatiotemporal model

Application and progress of techno-economic analysis and life cycle assessment in biomanufacturing of fuels and chemicals

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Green Chemical Engineering 2023年第2期4卷 189-198页

作者： Rongzhan fu Lixia kang Chenyue Zhang Qiang Fei Shaanxi Key Laboratory of Degradable Biomedical Materials School of Chemical EngineeringNorthwest UniversityXi'an710069China Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an710049China

To reduce the dependency on petroleum-based products and emission of greenhouse gas,renewable biofuels and chemicals play an important role to meet the unmatched energy demands of the rapidly growing population.However,most biofuel and chemical products do not reach the commercialization stage,mainly hindered by incomparable economics to petroproducts.Techno-economic assessment(TEA)is a useful tool to estimate eco-nomic performance,and identify bottlenecks for the development of biofuel and chemical production technology,meanwhile,life cycle assessment(LCA)is applied to assess sustainability by reducing the environmental impact of biofuel and chemical production.This present review covers TEA and LCA research progress in the manufacturing of biofuels and biochemical,and discusses the impacts of TEA and LCA results on the development and optimi-zation of biofuel and chemical production.In addition,challenges associated with TEA and LCA of biofuel and biochemical production were briefly overviewed,and potential approaches that may overcome such challenges were discussed enabling viable and sustainable biomanufacturing of fuels and chemicals.future integrated TEA and LCA studies could significantly promote the economic and sustainable development of the biomanufacturing process.

关键词： Techno-economic assessment Life cycle assessment Biomanufacturing fuels Chemicals Bioethanol Biodiesel

Impact angle constrained fuzzy adaptive fault tolerant IGC method for Ski-to-Turn missiles with unsteady aerodynamics and multiple disturbances

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1210-1226页

作者： GUO Hang WANG Zheng fu Bin CHEN kang fu Wenxing YAN Jie Research Center for Unmanned System Strategy Development Northwestern Polytechnical UniversityXi’an 710072China Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China

An impact angle constrained fuzzy adaptive fault tolerant integrated guidance and control method for Ski-to-Turn(STT)missiles subject to unsteady aerodynamics and multiple disturbances is proposed.Unsteady aerodynamics appears when flight vehicles are in a transonic state or confronted with unstable airflow.Meanwhile,actuator failures and multisource model uncertainties are introduced.However,the boundaries of these multisource uncertainties are assumed unknown.The target is assumed to execute high maneuver movement which is unknown to the missile.furthermore,impact angle constraint puts forward higher requirements for the interception accuracy of the integrated guidance and control(IGC)method.The impact angle constraint and the precise interception are established as the object of the IGC method.Then,the boundaries of the lumped disturbances are estimated,and several fuzzy logic systems are introduced to compensate the unknown nonlinearities and uncertainties.Next,a series of adaptive laws are developed so that the undesirable effects arising from unsteady aerodynamics,actuator failures and unknown uncertainties could be suppressed.Consequently,an impact angle constrained fuzzy adaptive fault tolerant IGC method with three loops is constructed and a perfect hit-to-kill interception with specified impact angle can be implemented.Eventually,the numerical simulations are conducted to verify the effectiveness and superiority of the proposed method.

关键词： integrated guidance and control(IGC) impact angle constraint unsteady aerodynamics fault tolerant control(FTC) actuator failures

ARK2 stabilizes the plus-end of microtubules and promotes microtubule bundling in Arabidopsis

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Journal of Integrative Plant Biology 2023年第1期65卷 100-116页

作者： Miao Lan Xianan Liu Erfang kang Ying fu Lei Zhu State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural UniversityBeijing 100193 China

Microtubule dynamics and organization are important for plant cell morphogenesis and development.The microtubule-based motor protein kinesins are mainly responsible for the transport of some organelles and vesicles,although several have also been shown to regulate microtubule organization.The ARMADILLO REPEAT KINESIN(ARK)family is a plant-specific motor protein subfamily that consists of three members(ARK1,ARK2,and ARK3)in Arabidopsis thaliana.ARK2 has been shown to participate in root epidermal cell morphogenesis.However,whether and how ARK2 associates with microtubules needs further elucidation.Here,we demonstrated that ARK2 co-localizes with microtubules and facilitates microtubule bundling in vitro and in vivo.Pharmacological assays and microtubule dynamics analyses indicated that ARK2 stabilizes cortical microtubules.Live-cell imaging revealed that ARK2moves along cortical microtubules in a processive mode and localizes both at the plus-end and the sidewall of microtubules.ARK2 therefore tracks and stabilizes the growing plus-ends of microtubules,which facilitates the formation of parallel microtubule bundles.

关键词： Arabidopsis kinesin microtubule bundle microtubule dynamic

Orexin receptor type 2 agonism inhibits thermogenesis in brown adipose tissue by attenuating afferent innervation

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The Journal of Biomedical Research 2022年第3期36卷 195-207,I0005,I0006页

作者： Mo-qiu Jia Yong-jin Wang Kang Fu Han Jiao Jia Sun Yuanqing Gao Key Laboratory of Cardiovascular and Cerebrovascular Medicine School of PharmacyNanjing Medical UniversityNanjingJiangsu 211166China

Orexin signaling has been associated with energy expenditure and brown adipose tissue(BAT)function.However,conflicting data exist in the field about how orexin signaling regulates BAT thermogenesis.In this study,we show that a specific orexin receptor type 2(OX2R)agonist[Ala11,D-Leu15]-OxB(OB-Ala)inhibited intrascapular brown adipose tissue(iBAT)thermogenesis by reducing sympathetic output to iBAT.This effect is mediated by OX2Rs located on afferent nerve endings innervating iBAT instead of brown adipocyte itself.Microinjection of OB-Ala into iBAT inhibited iBAT thermogenesis in mice upon cold exposure and neuronal activity in the paraventricular nucleus.Findings suggest that OB-Ala could inhibit iBAT thermogenesis by attenuating sensory input thereby inhibiting the sympathetic-sensory iBAT feedback loop.Our study uncovers a novel primary action site of orexin in the regulation of energy balance.

关键词： orexin receptor type 2 brown adipose tissue thermogenesis

Fin field-effect transistors based on 2D Bi_(2)O_(2)Se——a huge innovation of 2D transistors device structure

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中国科学:化学英文版 2023年第9期66卷 2439-2440页

作者： Qundong fu Beng kang Tay Zheng Liu School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore CINTRA CNRS/NTU/THALES UMI 3288Research Techno PlazaSingapore 637553Singapore

The continuous downscaling(sub 5-nm nodes) of the processing technology is severely hampered by the shortchannel effects of the silicon(Si) material, which degrade the transistor's performance and raise the demand in the development of new device structures and materials to overcome them. Two-dimensional(2D) semiconductors are promising candidates for next-generation electronic materials owing to their atomic thickness and van der Waals(vdW) surface.

关键词： transistors transistor overcome

Trust-Region Based Stochastic Variational Inference for Distributed and Asynchronous Networks

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Journal of Systems Science & Complexity 2022年第6期35卷 2062-2076页

作者： fu Weiming QIN Jiahu LING Qing kang Yu YE Baijia Department of Automation University of Science and Technology of ChinaHefei 230027China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China School of Computer Science and Engineering and Guangdong Province Key Laboratory of Computational ScienceSun Yat-Sen UniversityGuangzhou 510006China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230027China

Stochastic variational inference is an efficient Bayesian inference technology for massive datasets,which approximates posteriors by using noisy gradient estimates.Traditional stochastic variational inference can only be performed in a centralized manner,which limits its applications in a wide range of situations where data is possessed by multiple nodes.Therefore,this paper develops a novel trust-region based stochastic variational inference algorithm for a general class of conjugate-exponential models over distributed and asynchronous networks,where the global parameters are diffused over the network by using the Metropolis rule and the local parameters are updated by using the trust-region method.Besides,a simple rule is introduced to balance the transmission frequencies between neighboring nodes such that the proposed distributed algorithm can be performed in an asynchronous manner.The utility of the proposed algorithm is tested by fitting the Bernoulli model and the Gaussian model to different datasets on a synthetic network,and experimental results demonstrate its effectiveness and advantages over existing works.

关键词： Asynchronous networks Bayesian inference distributed algorithm stochastic variational inference trust-region method