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Base-controlled NHC-Ru-catalyzed transfer hydrogenation andα-methylation/transfer hydrogenation of ketones using methanol

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Chinese Chemical Letters 2024年第7期35卷 276-280页

作者： Ming Huang Xiuju cai yan Liu Zhuofeng Ke School of pharmacy School of clinical pharmacyGuangdong Pharmaceutical UniversityGuangzhou 510006China School of Materials Science&Engineering PCFM LabSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China

Herein,we report the NHC-Ru catalyst system that realizes the chemo-selective transformation of ketones with *** simply changing the base,a broad range of structurally diverse ketones,could be selectively and efficiently converted to the correspondingβ-methylated secondary alcohols or secondary ***,this catalytic system was very effective for the synthesis of bio-related molecules and deuterated alcohols,as well as the three-component coupling between methyl ketones,primary alcohols,and *** reaction mechanism was further revealed by experiment and DFT mechanistic investigations.

关键词： Ru complexes Methanol Ketones β-Methylated secondary alcohols Transfer hydrogenation

Research status and perspectives of MXene-based materials for aqueous zinc-ion batteries

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Rare Metals 2024年第5期43卷 1867-1885页

作者： Xiao-Yu Wang Qi-Hang yang Xin-yan meng meng-meng Zhen Zhen-Zhong Hu Bo-Xiong Shen School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300071China

Aqueous zinc-ion batteries(AZIBs)as green battery systems have attracted widespread attention in large-scale electrochemical energy storage devices,owing to their high safety,abundant Zn materials,high theoretica specific capacity and low redox *** there are some thorny issues in AZIBs that hinder their practical application,such as low intrinsic electron conductivity,slow ion migration kinetics,zinc dendrites and side ***-based materials with superior conductivity,large polar surface and abundant active sites can simultaneously serve as cathode materials,electrolyte additive and protection layer of anode to regulate redox reactions of *** various materials have been used to improve electrochemical performances of AZIBs there is a lack of in-depth discussion on the regulation mechanism of MXene-based materials for *** this review,we elaborate the research progress of MXenebased materials in AZIBs,including their application in cathode materials and inhibition of zinc *** the future prospects and development directions of MXenebased materials that may improve performance of AZIBs are prospected.

关键词： MXene Aqueous zinc-ion batteries Composite materials Zinc dendrites

Thermally cross-linkable hole-transport materials enable solution-processed blue OLED with LT95 over 150 h

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Science China Materials 2024年第9期67卷 2767-2777页

作者： Xinkang Zhang Hao yan Xiaopeng Zhang Hong meng School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen518055China

The solution-processed method for organic light-emitting diodes(OLEDs)offers the benefits of cost-effectiveness and enhanced material *** the multilayer architecture of solution-processed OLEDs(SOLEDs),the role of hole-transport materials(HTMs)is pivotal for cascade hole ***,commercial HTMs such as poly-(9,9-dioctylfluorene-alt-N-(4-sec-butylphenyl)-diphenylamine)(TFB)are hampered by incompatible energy levels and redissolution with overlayer solvent,prompting the exploration of cross-linkable HTMs(X-HTMs)for better *** this study,we have developed two novel small-molecule X-HTMs,N^(1),N^(1)′-((perfluoropropane-2,2-diyl)bis(4,1-phenylene))bis(N^(4),N^(4)-diphenyl-N^(1)-(4-vinylphenyl)benzene-1,4-diamine)(FTPA-V)and N,N′-((perfluoropropane-2,2-diyl)bis-(4,1-phenylene))bis(9-phenyl-N-(4-vinylphenyl)-9H-carbazol-3-amine)(FPCz-V),which incorporate thermally cross-linkable vinyl groups and electron-rich trifluoromethyl *** X-HTMs enhance interfacial contact through superior film formation and solvent resistance,along with optimal energy *** application of X-HTMs significantly enhances the efficiencies and longevities of blue,green,and red ***,blue SOLED incorporating FPCz-V exhibits unprecedented lifetime(LT95)extending to over 150 h,setting a new record for blue *** electrochemistry stability,high bond dissociation energy,and triplet energy levels of X-HTMs can effectively minimize exciton annihilation and prolong the *** findings underscore the potential of X-HTM optimization to propel the development of stable solution-processed luminescent technologies.

关键词： solution-processed OLED cross-linkable HTMs solvent resistance bond dissociation energy exciton-polaron annihilation

Effects of zeolite imidazole frameworks on rice seedlings (Oryza sativa L.): Phytotoxicity, transformation, and bioaccumulation

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Journal of Environmental Sciences 2024年第10期144卷 15-25页

作者： Chaofa Chen Yongqi Yao Chenghua Xing Yunyu Guo Luyi cai Jianfang yan Xi-Lin Wu Miaozhen cai College of Geography and Environmental Science Zhejiang Normal UniversityJinhuaZhejiang 321004China College of Agriculture Jinhua PolytechnicJinhuaZhejiang 321007China

Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental ***,their environmental fate and potential ecological impact on plants remain ***,we investigated the phytotoxicity,transformation,and bioaccumulation processes of two typical ZIFs(ZIF-8 and ZIF-67)in rice(Oryza sativa L.)under hydroponic ***-8 and ZIF-67 in the concentration of 50 mg/L decreased root and shoot dry weight maximally by 55.2%and 27.5%,53.5%and 37.5%,*** scanning electron microscopy(SEM)imaging combined with X-ray diffraction(XRD)patterns revealed that ZIFs on the root surface gradually collapsed and transformed into nanosheets with increasing cultivation *** fluorescein isothiocyanate(FITC)labeled ZIFs were applied to trace the uptake and translocation of ZIFs in *** results demonstrated that the transformed ZIFs were mainly distributed in the intercellular spaces of rice root,while they cannot be transported to culms and *** so,the Co and Zn contents of rice roots and shoots in the ZIFs treated groups were increased by 1145%and 1259%,145%and 259%,respectively,compared with the control *** findings suggested that the phytotoxicity of ZIFs are primarily attributed to the transformed ZIFs and to a less extent,the metal ions and their ligands,and they were internalized by rice root and increased the Co and Zn contents of *** study reported the transformation of ZIFs and their biological effectiveness in rice,highlighting the potential environmental hazards and risks of ZIFs to crop plants.

关键词： Zeolitic imidazolate frameworks (ZIFs) Rice(Oryza sativa L.) Phytotoxicity Transformed ZIFs ZIFs bioaccumulation

Exploring the transformative impact of traditional Chinese medicine on depression:Insights from animal models

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World Journal of Psychiatry 2024年第5期14卷 607-623页

作者： yan yang yan-Kun Chen meng-Zhou Xie School of Nursing Hunan University of Chinese MedicineChangsha 410200Hunan ProvinceChina Precision Medicine R&D Center Zhuhai Institute of Advanced TechnologyChinese Academy of SciencesZhuhai 519000Guangdong ProvinceChina School of Chinese Medicine Hunan University of Chinese MedicineChangsha 410200Hunan ProvinceChina Hunan Engineering Technology Research Center for Medicinal and Functional Food Hunan University of Chinese MedicineChangsha 410200Hunan ProvinceChina Key Laboratory of TCM Heart and Lung Syndrome Differentiation and Medicated Diet and Dietotherapy Hunan University of Chinese MedicineChangsha 410200Hunan ProvinceChina

Depression,a prevalent and complex mental health condition,presents a significant global health *** is one of the most frequent mental disorders;deaths from it account for 14.3%of people *** recent years,the integration of complementary and alternative medicine,including traditional Chinese medicine(TCM),has gained attention as a potential avenue for addressing *** comprehensive review critically assesses the efficacy of TCM interventions in alleviating depressive *** in-depth look at different research studies,clinical trials,and meta-analyses is used in this review to look into how TCM practices like herbal formulations,acupuncture,and mindbody practices *** review looks at the quality of the evidence,the rigor of the methods,and any possible flaws in the current *** gives us an idea of where TCM stands right now in terms of treating *** comprehensive review aims to assess the efficacy of TCM interventions in alleviating depressive *** order to learn more about their possible healing effects,the study also looks into how different types of TCM work,such as herbal formulas,acupuncture,and mind-body practices.

关键词： Traditional Chinese medicine Depression Efficacy Treatment Holistic approach

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： meng-yang Liu Hong-wu Tang Sai-yu Yuan Jing yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

Transition metals for stabilizing lithium metal anode:advances and perspectives

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Tungsten 2024年第1期6卷 212-229页

作者： Si-Cheng Miao Ye Jia Zhi-Wen Deng yan Deng Ruo-Xuan Chen Xue-Mei Zhang Chang-Haoyue Xu meng Yao Wen-Long cai Department of Advanced Energy Materials College of Materials Science and EngineeringSichuan UniversityChengdu 610064China

As the capacity of lithium-ion batteries gradually reaches its limit,the high-capacity characteristics of lithium metal batteries(LMBs)make them one of the most promising electrochemical energy storage devices ***,uncontrolled lithium dendrite growth can cause poor cell performance and severe safety issues,seriously slowing down the commercialization of *** metals(TMs)are lithiophilic materials that effectively stabilize lithium metal anode(LMA)and inhibit dendrite ***,the growth of lithium dendrites and the performance of TMs in stabilizing lithium metals are comprehensively discussed in this ***,we elucidated the formation mechanisms of lithium dendrite,and we put forward several strategies to suppress lithium dendrite formation based on the understanding of these ***,the application of TMs and their compounds to stabilize LMA and their corresponding mechanisms are comprehensively ***,further research perspectives of TMs in stabilizing LMA are emphasized in detail.

关键词： Transition metals Lithium metal batteries Lithium dendrite Solid electrolyte interphase Formation mechanism

Braille Character Segmentation Algorithm Based on Gaussian Diffusion

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Computers, Materials & Continua 2024年第4期79卷 1481-1496页

作者： Zezheng meng Zefeng cai Jie Feng Hanjie Ma Haixiang Zhang Shaohua Li School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou310018China

Optical braille recognition methods typically employ existing target detection models or segmentation modelsfor the direct detection and recognition of braille characters in original braille images. However, these methodsneed improvement in accuracy and generalizability, especially in densely dotted braille image environments. Thispaper presents a two-stage braille recognition framework. The first stage is a braille dot detection algorithmbased on Gaussian diffusion, targeting Gaussian heatmaps generated by the convex dots in braille images. Thisis applied to the detection of convex dots in double-sided braille, achieving high accuracy in determining thecentral coordinates of the braille convex dots. The second stage involves constructing a braille grid using traditionalpost-processing algorithms to recognize braille character information. Experimental results demonstrate that thisframework exhibits strong robustness and effectiveness in detecting braille dots and recognizing braille charactersin complex double-sided braille image datasets. The framework achieved an F1 score of 99.89% for Braille dotdetection and 99.78% for Braille character recognition. Compared to the highest accuracy in existing methods,these represent improvements of 0.08% and 0.02%, respectively.

关键词： Computer vision image recognition optical braille recognition

Warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography

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Defence Technology（防务技术） 2024年第7期37卷 162-172页

作者： Pengyu Hu Jiangpeng Wu Zhengang yan meng He Chao Liang Hao Bai Xi'an Modern Control Technology Research Institute Xi'an710065China Xi'an OET Science and Technology Co. LtdXi'an710076China

High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high ***,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment *** address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo ***,background difference algorithm is utilized to extract the center and area of each fragment in the image ***,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment *** reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial ***,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.

关键词： Warhead fragment measurement High speed photography Stereo vision Multi-object tracking Spatio-temporal reconstruction