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Synergistic Brønsted Base/Photoredox-Catalyzed Three-Component Coupling with Malonates to Synthesize δ-Hydroxy Esters and δ-Keto Esters

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Chinese Journal of Chemistry 2024年第9期42卷 957-962页

作者： Ting Li wei Wang Ming Dong Zhije Zhang sha Yu Zhengchu Chen Siping wei Dong yi Green Pharmaceutical Technology Key Laboratory of Luzhou City Central Nervous System Drug Key Laboratory of Sichuan ProvinceSchoolof PharmacySouthwestMedicalUniversityLuzhouSichuan 646000China Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province LuzhouSichuan 646000China

Multicomponent alkene 1,2-dicarbofunctionalizations(DCFs)have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C-C double bond in one step for enhancing molecular complexity and *** the best of our knowledge,there is only one report on photoredox-catalyzed three-component DCFs with malonates through the radical−radical cross-coupling,while photoredox-catalyzed radical-polar crossover(RPC)-type DCFs with malonates were still ***,we describe a redox-neutral RPC-type 1,2-dialkylation of styrenes with malonates and aldehydes through the synergistic Brønsted base/photoredox catalysis *** transition-metal-free strategy provides an efficient and clean approach to a broad variety ofδ-hydroxy esters and also features exceptionally mild conditions,wide compatibility of substrate scope and functional groups,and high atomic ***,three-component 1,2-alkylacylation from the same starting materials was achieved in one-pot manner through such RPC-type coupling and subsequent two-electron oxidation process,providing a set ofδ-keto esters of interest in pharmaceutical research.

关键词： Alkene difunctionalization Photoredox catalysis Malonates Radical reactions C-C coupling Synthetic methods Aldehydes Alkylation Multicomponentreactions

Insight into the development of electrolytes for aqueous zinc metal batteries from alkaline to neutral

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Chinese Chemical Letters 2024年第2期35卷 232-241页

作者： An Duan sha Luo wei Sun School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Aqueous zinc metal batteries are considered as promising candidates for next-generation electrochemical energy storage devices,especially for large-scale energy storage,due to the advantages of high-safety,high energy density and low *** the bridge connecting cathode and anode,electrolyte provides a realistic operating *** alkaline and neutral aqueous zinc metal batteries,issues associated with electrolyte and anode are still *** this review,we reveal the development and evolution of electrolytes for aqueous zinc metal batteries from alkaline to neutral via the description of fundamentals and challenges in terms of comparison and *** also elaborate the strategies in electrolytes regulation and highlight the basic roles and progresses in additives engineering.

关键词： Aqueous electrolytes Zinc metal batteries pH-dependent chemistry Electrolyte regulation Additives engineering

An improved interval model updating method via adaptive Kriging models

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 497-514页

作者： sha wei yifeng CHEN Hu DING Liqun CHEN shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample ***,the surrogate model in IMU methods mostly adopts the one-time construction *** makes the accuracy of the surrogate model highly dependent on the experience of users and affects the accuracy of IMU ***,an improved IMU method via the adaptive Kriging models is *** method transforms the objective function of the IMU problem into two deterministic global optimization problems about the upper bound and the interval diameter through universal grey *** optimization problems are addressed through the adaptive Kriging models and the particle swarm optimization(PSO)method to quantify the uncertain parameters,and the IMU is *** the construction of these adaptive Kriging models,the sample space is gridded according to sensitivity *** sampling is then performed in key subspaces based on the maximum mean square error(MMSE)*** interval division coefficient and random sampling coefficient are adaptively adjusted without human interference until the model meets accuracy *** effectiveness of the proposed method is demonstrated by a numerical example of a three-degree-of-freedom mass-spring system and an experimental example of a butted cylindrical *** results show that the updated results of the interval model are in good agreement with the experimental results.

关键词： interval model updating(IMU) non-probabilistic uncertainty adaptive Kriging model surrogate model grey number

Recent progress of gastroesophageal reflux after endoscopic myotomy

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World Journal of Gastroenterology 2024年第34期30卷 3926-3928页

作者： Xuan Yan wei-Hong sha The First School of Clinical Medicine Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Gastroenterology and Hepatology Guangdong Provincial People’s HospitalGuangzhou 510080Guangdong ProvinceChina

Per-oral endoscopic myotomy(POEM)is an innovative minimally invasive technique and has emerged as the preferred modality for treating achalasia and spastic esophageal disorders in numerous specialized centers *** reflux(GER)is a common complication following POEM ***,an article in the World Journal of Gastroenterology,providing a comprehensive update on post-POEM *** this article,the authors present novel insights and strategies that offer valuable implications for endoscopy.

关键词： Per-oral endoscopic myotomy Gastroesophageal reflux Progress Treatment Update

A Rapid and Effective HPLC Method for Identification of Bovis Calculus in Chinese Patent Medicines

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Chinese Herbal Medicines 2013年第3期5卷 224-233页

作者： XIA Jing XIA Li WANG wei-yi sha yi-wei WANG Ke JI Shen shanghai Institute for Food and Drug Control Guangdong Food and Drug Vocational College Key Laboratory of Marine Biogenetic Resources Third Institute of OceanographyState Oceanic Administration (SOA) shanghai Chongming Institute for Food and Drug Control

Objective Due to the limited resource and the large demand,many kinds of Bovis Calculus(BC) including artificial Bovis Calculus(ABC),in vivo cultured Bovis Calculus(in vivo CBC),and in vitro cultured Bovis Calculus(in vitro CBC)were used in Chinese patent medicines(CPMs).Previous studies have shown that the chemical constituents of ABC and their properties were different from other *** two types of CBC with much higher price than ABC were approximately equivalent with natural Bovis Calculus in quality and clinical *** aim of the study is to establish a rapid and effective method for the identification of BC in *** An HPLC method with the higher specificity for analyzing bilirubin was established to distinguish ABC from other three kinds of BC by comparing the change of bilirubin content with the addition of EDTA-2Na as the extraction solvent and *** The bilirubin content in CPMs containing ABC was basically unchanged,while that in CPMs containing other kinds of BC showed significant *** proposed method was employed to analyze a variety of CPMs containing Bovis Calculus(CPMBCs) and proven to be *** An effective analytical method is established for the quality control of CPMBCs and further ensures the safety and efficacy of these drugs in clinical practice.

关键词： artificial Bovis Calculus bilirubin Bovis Calculus Chinese patent medicines cultured Bovis Calculus EDTA-2Na solution

Nitrogen-doping boosts *CO utilization and H2O activation on copper for improving CO2 reduction to C2+ products

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Green Energy & Environment 2024年第9期9卷 1459-1465页

作者： yisen Yang Zhonghao Tan Jianling Zhang Jie Yang Renjie Zhang sha Wang yi Song Zhuizhui Su Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Center for Carbon Neutral Chemistry Institute of Chemistry Chinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences Key Laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

To improve the electrocatalytic transformation of carbon dioxide （CO2） to multi-carbon (C2+) products is of great *** we developed a nitrogen-doped Cu catalyst,by which the maximum C2+Faradaic efficiency can reach 72.7%in flow-cell system,with the partial current density reaching 0.62 A *** in situ Raman spectra demonstrate that the *CO adsorption can be strengthened on such a N-doped Cu catalyst,thus promoting the*CO utilization in the subsequent C–C coupling ***,the water activation can be well enhanced by N doping on Cu *** to the synergistic effects,the selectivity and activity for C2+products over the N-deoped Cu catalyst are much improved.

关键词： Electrocatalytic CO 2 reduction reaction Copper catalyst Doping Multi-carbon products In situ Raman measurement

Determining the planting year of navel orange trees in mountainous and hilly areas of southern China:a remote sensing based method

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Journal of Mountain Science 2024年第10期21卷 3293-3305页

作者： LEI Juncheng WANG sha WANG Yuandong LUO wei School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China School of Chemistry and Chemical Engineering Gannan Normal UniversityGanzhou 341000China

Remote sensing has demonstrated validity in determining the planting year of deciduous fruit trees;however,its effectiveness in ascertaining the planting year of evergreen fruit trees remains ***,the sources of error associated with using remote sensing to determine the planting year of fruit trees remain *** study investigates several cultivated sweet orange(Citrus sinensis)varieties,which are extensively cultivated throughout subtropical *** analyzed Landsat time series data from 132 navel orange orchards in Gannan,covering the period from 1993 to *** each orchard,Google Earth Engine was employed to extract three vegetation indices—Enhanced Vegetation Index(EVI),Normalized Difference Vegetation Index(NDVI),and Normalized Burn Ratio(NBR)—for each available date,thereby generating three distinct vegetation index time *** planting year of navel orange trees was identified based on abrupt changes observed in these time *** principal sources of error in determining the planting year were investigated using the Wilcoxon signed-rank test,Spearman's correlation analysis,and Kruskal-Wallis H *** findings include:(1)Following the planting of navel orange trees,EVI,NDVI,and NBR exhibited fluctuations and a gradual increase over time,peaking approximately 10 to 15 years later.(2)The vegetation index time series derived from Landsat imagery effectively determined the planting year of evergreen navel orange trees in orchards,even within highly fragmented *** these indices,NDVI and NBR time series outperformed the EVI time ***,the average determination errors for EVI,NDVI,and NBR time series were 6.4,1.8,and 2.8 years,respectively.(3)Major sources of error included the methods used to construct the time series,the selection of vegetation indices,and the orchard management ***,this study provides a viable method for determining the planting year of evergreen navel orange trees in f

关键词： Time series Remote sensing Google Earth Engine Gannan Subtropics

Low-carbon development policies and achievements in the context of the livestock sector in China

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 367-380页

作者： sha wei Junming FAN Yanfeng TIAN Hongmin DONG Institute of Environmental and Sustainable Development in Agriculture Chinese Academy of Agriculture SciencesBeijing 100081China Inner Mongolia YouRan Dairy Co. Ltd.Hohhot 010070China

Rapid growth and a vast transition of Chinese livestock industry driven by economic incentives make it become an important contributor on climate change over the last four *** study first analyzes the evolving lowcarbon livestock development policies and regulations,then an assessment and explanations of the achievements and non-achievements are *** findings reveal that China began to pay attention to low-carbon development policy starting in the early ***,only after the cyclic and green concept became the main sustainable development policy,China began to move seriously toward low-carbon livestock *** policy instruments were introduced,including moderate scale,feed optimization,manure resource utilization,facility and equipment allocation rate,energy conservation and ***,achievements were made in introducing such ***,due to the large share of standard agriculture and regional resources,and environmental diversity,such policies may have little effect in *** divergence between the policies and actual practices are explained,and important policies applicable to all developing countries are also recommended.

关键词： Low carbon livestock development policy recommendations divergence carbon market

Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2479-2505页

作者： Mingzhe Huang Mi Xiao Liang Gao Mian Zhou wei sha Jinhao Zhang State Key Lab of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight *** this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is *** method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell *** geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational *** topological configurations of thin-shell structures are described by constructing the effective density field on the *** volume constraints are imposed in the proximity of each control point to obtain bone-like cellular *** facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global *** numerical examples are provided to demonstrate the effectiveness of the proposed *** simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness.

关键词： Cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells