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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

Synergistic effect of carbon nanotube and encapsulated carbon layer enabling high-performance SnS_2-based anode for lithium storage

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Journal of Energy Chemistry 2024年第10期97卷 700-709,I0015页

作者： Chunwei dong Yongjin Xia Zhijiang Su Zhihua Han Yang dong Jingyun Chen Fei Hao Qiyao yu Qing Jiang Jiaye Ye National Instituteof Clean-and-Low-Carbon Energy Beijing 102209China Key Laboratory of Automobile Materials Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022JilinChina State Key Laboratory of Explosion Science and Technology School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China School of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Tin disulfide(SnS_(2)),due to large interlayer spacing and high theoretical capacity,is regarded as a prospective anode material for lithium-ion ***,the poor electron conductivity of SnS_(2) and huge volumetric change during the lithiation/delithiation process lead to a rapid capacity decay of the battery,hindering its *** address these issues,herein,SnS_(2) is in-situ grown on the surface of carbon nanotubes(CNT)and then encapsulated with a layer of porous amorphous carbon(CNT/SnS_(2)@C)by simple solvothermal and further carbonization *** synergistic effect of CNT and porous carbon layer not only enhances the electrical co nductivity of SnS_(2) but also limits the huge volumetric change to avoid the pulverization and detachment of SnS_(2).Density functional theo ry calculations show that CNT/SnS_(2)@C has high Li^(+)adsorption and lithium storage capacity achieving high reaction ***,cells with the CNT/SnS_(2)@C anode exhibit a high lithium storage capacity of 837mAh/g after 100 cycles at 0.1 A/g and retaining a capacity of 529.8 mAh/g under 1.0 A/g after 1000 *** study provides a fundamental understanding of the electrochemical processes and beneficial guidance to design high-performance SnS_(2)-based anodes for LIBs.

关键词： Lithium-ion batteries Porous amorphous carbon Carbon nanotubes SnS_(2)-based anode Density functional theory calculations

The BTB/TAZ domain-containing protein CmBT1-mediated CmANR1 ubiquitination negatively regulates root development in chrysanthemum

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Journal of Integrative Plant Biology 2024年第2期66卷 285-299页

作者： lian-Da Du Zhang-Ji Guan Yan-Hong Liu Hui-dong Zhu Quan Sun Da-Gang Hu Cui-Hui Sun Shandong Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient Production College of Horticulture Science and EngineeringShandong Agricultural UniversityTaian 271018China

Roots are fundamental for plants to adapt to variable environmental *** development of a robust root system is orchestrated by numerous genetic determinants and,among them,the MADS-box gene ANR1 has garnered substantial *** research has demonstrated that,in chrysanthemum,CmANR1positively regulates root system ***,the upstream regulators involved in the CmANR1-mediated regulation of root development remain *** this study,we successfully identified bric-a-brac,tramtrack and broad(BTB)and transcription adapter putative zinc finger(TAZ)domain protein CmBT1 as the interacting partner of CmANR1 through a yeasttwo-hybrid(Y2H)screening ***,we validated this physical interaction through bimolecular fluorescence complementation and pull-down *** assays revealed that CmBT1 exerted a negative influence on root development in *** both in vitro and in vivo assays,it was evident that CmBT1mediated the ubiquitination of CmANR1 through the ubiquitin/26S proteasome *** ubiquitination subsequently led to the degradation of the CmANR1 protein and a reduction in the transcription of CmANR1-targeted gene CmPIN2,which was crucial for root development in *** analysis suggested that CmBT1 modulated root development,at least in part,by regulating the level of CmANR1 ***,these findings shed new light on the regulatory role of CmBT1 in degrading CmANR1 through ubiquitination,thereby repressing the expression of its targeted gene and inhibiting root development in chrysanthemum.

关键词： chrysanthemum MADS-box transcription factor root development

平行双关节坐标测量机圆光栅测角误差补偿技术

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南京理工大学学报 2009年第5期33卷 659-662页

作者：于连栋丁洋程文涛合肥工业大学仪器科学与光电工程学院安徽合肥230009

该文探讨了一种三自由度(DOF)平行双关节坐标测量机的测量原理和测量模型。分析了该测量机上的圆光栅测角误差对测量机测量精度的影响,给出了测角误差的补偿公式,利用该公式优化了测量机的测量模型。采用标准多面棱体和光电自准直仪对2... 详细信息

该文探讨了一种三自由度(DOF)平行双关节坐标测量机的测量原理和测量模型。分析了该测量机上的圆光栅测角误差对测量机测量精度的影响,给出了测角误差的补偿公式,利用该公式优化了测量机的测量模型。采用标准多面棱体和光电自准直仪对2个圆光栅的测角误差进行实验检定,并对测角误差修正前后的平行双关节坐标测量机测量精度进行了实验比对。结果表明,测量的极限偏差由0.033 mm降至0.015 mm,而标准差由0.0141 mm降为0.0061 mm,说明修正2个圆光栅的测角误差可大幅提高该测量机的测量精度。

关键词：平行双关节坐标测量机圆光栅误差补偿

Three anti-inflammatory polysaccharides from Lonicera japonica Thunb.:insights into the structure-function relationships

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Food Science and Human Wellness 2024年第4期13卷 2197-2207页

作者： yu Liu Hongjing dong dongxiao Sun-Waterhouse Wenwen Li Bin Zhang Jinqian yu Zhichang Qiu Zhenjia Zheng Key Laboratory of Food Nutrition and Health in Universities of Shandong College of Food Science and EngineeringShandong Agricultural UniversityTai’an 271018China Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province Shandong Analysis and Test CenterQilu University of Technology(Shandong Academy of Sciences)Jinan 250014China School of Chemical Sciences The University of AucklandPrivate Bag 92019New Zealand

This study demonstrates the feasibility of producing three polysaccharides(neutral LJP-1,acidic LJP-2 and acidic LJP-3)with significant in vitro and in vivo anti-inflammatory activities from the flowers of Lonicera *** three polysaccharides differed in chemical composition,molecular weight(Mw)distribution,glycosidic linkage pattern,functional groups and *** exhibited excellent protective effects(in a dose-dependent manner)in lipopolysaccharide-injured RAW264.7 macrophages and Cu SO4-damaged zebrafish via reducing NO production and inhibiting the overexpressions of inflammation-related transcription factors,inflammatory proteins and cytokines in the NF-κB/MAPK signaling *** antiinflammatory effects varied owing to their different molecular characteristics and chemical ***,LJP-2 at 400μg/m L was the most ***-2 consisted mainly of→5)-α-L-Araf(1→,→4)-α-LGalp A(1→and→2)-α-L-Rhap(1→residues with terminal T-β-***,honeysuckle flowers are good sources of anti-inflammatory polysaccharides,and precise fractionation enables the production of potent antiinflammatory agents for the development of functional foods and healthcare products.

关键词： Honeysuckle polysaccharides Fractionation Molecular characteristics Anti-inflammatory properties Structure-function relationship

Strengthening mechanism and forming control of linear friction welded GH4169 alloy joints

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Chinese Journal of Aeronautics 2024年第4期37卷 609-626页

作者： yu SU Xiawei YANG Tingxi MENG Xinyuan HE dong WU Wenya LI Shuo YIN State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Friction Welding Technologies School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Manufacturing and Biomedical EngineeringParsons BuildingTrinity College DublinThe University of DublinDublin 2Ireland

Numerical simulation and experimental research on Linear Friction Welding(LFW) for GH4169 superalloy were carried out. Based on the joint microstructure and mechanical properties,a suitable welding process was determined, which provided an important theoretical basis for the manufacture and repair of aeroengine components such as the superalloy blisk. The results show that the joint strain rate gradually increases with the increase of welding frequency, and the deformation resistance of the thermoplastic metal increases in the welding process, resulting in the interface thermoplastic metal not being extruded in time to form a flash, so the joint shortening amount gradually decreases. The thermoplastic metal in the center of the welding surface is kept at high welding temperature for a long time, resulting in the decrease of the joint strength. The microhardness of the joint shows a “W” distribution perpendicular to the weld, and most of the joints break in the Thermo-Mechanically Affected Zone(TMAZ) with high tensile strength and low *** the welding area is increased without changing the aspect ratio of the welding surface, the interface peak temperature increases gradually, and the joint shortening amount decreases with the increase of the welding interface size.

关键词： Linear Friction Welding(LFW) Microstructure Mechanical properties Numerical simulation Joint shortening amount

Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

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Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao Jian-Ping Huang Xin-Ru Mu Ji-dong Yang yu-Jian Zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

The etching strategy of zinc anode to enable high performance zinc-ion batteries

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Journal of Energy Chemistry 2024年第1期88卷 125-143,I0004页

作者： Xueqing Fu Gaopeng Li Xinlu Wang Jinxian Wang Wensheng yu Xiangting dong dongtao Liu School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022JilinChina Department of Chemistry Northeast Normal UniversityChangchun 130024JilinChina

Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic ***,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical *** etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical ***,there is no comprehensive review of the etching strategy of Zn *** review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other ***,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.

关键词： Zinc-ion batteries Zn anode Etching 3D structures Dendrite-free

A Symmetric-Actuating Linear Piezoceramic Ultrasonic Motor Capable of Producing a Scissoring Effect

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Research 2024年第1期2023卷 571-581页

作者： Zhanmiao Li Xingyu Yi Rongqi Zhu Zhonghui yu Xiaoting yuan MohammadJavad PourhosseiniAsl Shuxiang dong School of Materials Science and Engineering Peking UniversityBeijing 100871China College of Mechatronics and Control Engineering and Institute for Advanced StudyShenzhen UniversityShenzhen 518051China

Conventionally,to produce a linear motion,one motor’s stator is employed to drive one runner moving forward or *** far,there is almost no report of one electromechanical motor or piezoelectric ultrasonic motor that can directly generate two symmetrical linear motions,while this function is desired for precise scissoring and grasping in the minimally invasive surgery ***,we report a brandnew symmetric-actuating linear piezoceramic ultrasonic motor capable of generating symmetrical linear motions of two outputs directly without additional mechanical transmission *** key component of the motor is an(2×3)arrayed piezoceramic bar stator operating in the coupled resonant mode of the first longitudinal(L_(1))and third bending(B_(3))modes,leading to symmetric elliptical vibration trajectories at its two ends.A pair of microsurgical scissors is used as the end-effector,demonstrating a very promising future for high-precision microsurgical operations.

关键词： field symmetric backward