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Photocatalytic C–X borylation of aryl halides by hierarchical SiC nanowire-supported Pd nanoparticles

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Chinese Journal of Catalysis 2020年第2期41卷 357-363页

作者： zhi-feng jiao Ji-Xiao Zhao Xiao-Ning Guo Xiang-Yun Guo State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina Institut für Anorganische Chemie and Institute for Sustainable Chemistry&Catalysis with BoronJulius-Maximilians-Universit?t WürzburgAm Hubland97074 WürzburgGermany School of Petrochemical Engineering Changzhou UniversityChangzhou 213164JiangsuChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Hierarchical Si C nanowire-supported Pd nanoparticles showed high photocatalytic activity for the C–X(X = Br, I) borylation of aryl halides at 30 °C. The Si C/Pd Mott-Schottky contact enhances the rapid transfer of the photogenerated electrons from Si C to the Pd nanoparticles. As a result, the concentrated energetic electrons in the Pd nanoparticles can facilitate the cleavage of C–I or C–Br bonds, which normally requires high-temperature thermal processes. We show that the present Pd/Si C photocatalyst is capable of catalyzing the transformation of a large variety of aryl halides to their corresponding boronate esters under visible light irradiation, with excellent yields.

关键词： Boronate esters Carbon-halogen activation Hierarchical SiC nanowires Pd nanoparticles Photocatalysis

Microstructural characterization and mechanical properties of(TiC+TiB)/TA15 composites prepared by an in-situ synthesis method

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China Foundry 2024年第2期21卷 168-174页

作者： zhi-yong Zhang jiao-jiao Cheng Jia-qi Xie Shi-bing Liu Kun Shi Jun Zhao Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China National Key Laboratory of Advanced Casting Technologies Shenyang 110022China

Titanium matrix composites reinforced with ceramic particles are considered a promising engineering material due to their combination of high specific strength,low density,and high *** this study,the TA15-based composites reinforced with a volume fraction of 10% to 25%(TiB+TiC)were prepared using powder metallurgy and casting *** characterization and phase constitution were examined using optical microscopy(OM),scanning electron microscopy(SEM),and X-ray diffraction(XRD).In addition,the microhardness,room temperature(RT)and high temperature(HT)tensile properties of the composites were *** revealed that the reinforcements are distributed uniformly even in the composites with a high volume of TiB and ***,as the volume fraction exceeds 15%,TiB and TiC particles become coarsening and exhibit rod-like and dendritic-like *** increases gradually from 321.2 HV for the base alloy to a maximum of 473.3 HV as the reinforcement increases to 25vol.%.Tensile test results indicate that a reinforcement volume fraction above 20% is beneficial for enhancing tensile strength and yield strength at high temperatures,but it has an adverse effect on room temperature ***,if the reinforcement volume fraction is below 20%,it can improve high-temperature elongation when the temperature exceeds 600℃.

关键词： titanium matrix composites microstucture microhardness tensile properties in-situ synthesis

Prediction of undeformed chip thickness distribution and surface roughness in ultrasonic vibration grinding of inner hole of bearings

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 311-323页

作者： Yanqin LI Daohui XIANG Guofu GAO feng jiao Bo ZHAO School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China

Ultrasonic vibration grinding differs from traditional grinding in terms of its material removal *** randomness of grain-workpiece interaction in ultrasonic vibration grinding can produce variable chips and impact the surface roughness of ***,previous studies used iterative method to calculate the unformed chip thickness(UCT),which has low computational *** this study,a symbolic difference method is proposed to calculate the *** UCT distributions are obtained to describe the stochastic interaction characteristics of ultrasonic grinding ***,the UCT distribution characteristics under different machining parameters are ***,a surface roughness prediction model is established based on the UCT ***,the correctness of the model is verified by *** study provides a quick and accurate method for predicting surface roughness in longitudinal ultrasonic vibration grinding.

关键词： Ultrasonic vibration grinding Undeformed chip thickness(UCT) Distribution characteristics Surface roughness

Chlorajaponins A—Q,Lindenane-Related Sesquiterpenoid Dimers from Chloranthus japonicus and Their Biological Activities

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Chinese Journal of Chemistry 2024年第11期42卷 1247-1259页

作者： Wei-jiao feng Yue Gu Pei-zhi Huang Hong-Ying Yang Rui Zhang Yi-Lin He Ting-Hong Lv Ya Li Kun Gao State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhouGansu730000 China Research Institute Lanzhou Jiaotong UniversityLanzhouGansu730070 China

Seventeen undescribed lindenane-related sesquiterpenoid dimers,chlorajaponins A—Q(1—17),and 13 reported analogs(18—30)were isolated from Chloranthus japonicus *** 1 possesses an unprecedented 3/5/7/5/5/6/5/3 fused octacyclic scaffold,featuring a 6(5→4)-abeo-lindenane monomer,while 2 exhibits a 3/5/6/6/5/6/5/3 fused octacyclic *** structures were determined through a combination of spectroscopic analyses and X-ray *** 1,2,and 18 demonstrated significant inhibitory effects on lipid accumulation and effectively reduced the levels of triglycerides and total cholesterol,as well as the levels of aspartate aminotransferase and alanine aminotransferase in a HepG2 cell *** addition,compounds 1,2,and 18 significantly suppressed the protein expression of the fatty acid synthase(FASN)and the sterol regulatory element-binding protein 1(SREBP1).Moreover,the anti-inflammatory assay showed that compounds 19—22 and 25 inhibited the NO production induced by lipopolysaccharide in RAW 264.7 macrophages with IC50 values of 7.89±0.44,6.25±0.46,2.98±0.29,10.77±0.60,and 3.60±0.28μmol/L.

关键词： Chloranthus japonicus Lindenane-type sesquiterpenoid dimers Lipid-lowering activity Anti-inflammatory activity NMR spectroscopy Natural products X-ray diffraction

Buckling Properties of Water-Drop-Shaped Pressure Hulls with Various Shape Indices Under Hydrostatic External Pressure

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China Ocean Engineering 2024年第1期38卷 1-17页

作者： DING Xiao-de ZHANG Jian WANG Fang jiao Hui-feng WANG Ming-lu School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Shanghai Engineering Research Center of Marine Renewable Energy College of Engineering Science and Technol-ogyShanghai Ocean UniversityShanghai 201306China China Ship Scientific Research Center Wuxi 214082China

The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater ***,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape *** critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s *** numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were *** results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical *** formula can be extended to estimate the buckling capacity of water-drop-shaped pressure *** addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping ***,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical *** experimental results were consistent with the numerical *** results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt *** paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories.

关键词： buckling pressure hull water drop underwater observatory

Flexible,high-density,laminated ECoG electrode array for high spatiotemporal resolution foci diagnostic localization of refractory epilepsy

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Bio-Design and Manufacturing 2024年第4期7卷 388-398页

作者： Yafeng Liu Zhouheng Wang Yang jiao Ying Chen Guangyuan Xu Yinji Ma Xue feng Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Laboratory of Flexible Electronics Technology Tsinghua UniversityBeijing 100084China College of Artificial Intelligence Southwest UniversityChongqing 400715China Institute of Flexible Electronics Technology of THU Jiaxing 314000China Qiantang Science and Technology Innovation Center Hangzhou 310016China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China

High spatiotemporal resolution brain electrical signals are critical for basic neuroscience research and high-precision focus diagnostic localization,as the spatial scale of some pathologic signals is at the submillimeter or micrometer *** entails connecting hundreds or thousands of electrode wires on a limited *** study reported a class of flexible,ultrathin,highdensity electrocorticogram(ECoG)electrode *** challenge of a large number of wiring arrangements was overcome by a laminated structure design and processing technology *** flexible,ultrathin,high-density ECoG electrode array was conformably attached to the cortex for reliable,high spatial resolution electrophysiologic *** minimum spacing between electrodes was 15μm,comparable to the diameter of a single *** hundred electrodes were prepared with an electrode density of 4444 mm^(-2).In focal epilepsy surgery,the flexible,high-density,laminated ECoG electrode array with 36 electrodes was applied to collect epileptic spike waves inrabbits,improving the positioning accuracy of epilepsy lesions from the centimeter to the submillimeter *** flexible,high-density,laminated ECoG electrode array has potential clinical applications in intractable epilepsy and other neurologic diseases requiring high-precision electroencephalogram acquisition.

关键词： Electrocorticogram(ECoG)electrode Epilepsy High density High resolution Laminated structure

Further study on the genesis of lamellar calcite veins in lacustrine black shale--A case study of Paleogene in Dongying Depression, China

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Petroleum Science 2024年第3期21卷 1508-1523页

作者： Guan-Min Wang Yun-jiao Zhang Zi-Yuan Yin Rui Zhu zhi-Yao Hou Yu Bai School of Geosciences China University of Petroleum(East China)Qingdao266580ShandongChina

Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark *** formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving *** paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe *** distinct types of calcite veins have been identified:granular calcite veins and sparry calcite *** two types differ significantly in color,grain structure,morphology,and *** further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite *** granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite *** granular calcite veins were likely influenced by the reduction of sulfate *** the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic *** contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion *** carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of *** opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarb

关键词： Calcite veins Shale diagenesis Material source Formation period Formation mechanism

A Comprehensive Survey on Deep Learning Multi-Modal Fusion:Methods,Technologies and Applications

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Computers, Materials & Continua 2024年第7期80卷 1-35页

作者： Tianzhe jiao Chaopeng Guo Xiaoyue feng Yuming Chen Jie Song Software College Northeastern UniversityShenyang110819China

Multi-modal fusion technology gradually become a fundamental task in many fields,such as autonomous driving,smart healthcare,sentiment analysis,and human-computer *** is rapidly becoming the dominant research due to its powerful perception and judgment *** complex scenes,multi-modal fusion technology utilizes the complementary characteristics of multiple data streams to fuse different data types and achieve more accurate ***,achieving outstanding performance is challenging because of equipment performance limitations,missing information,and data *** paper comprehensively reviews existing methods based onmulti-modal fusion techniques and completes a detailed and in-depth *** to the data fusion stage,multi-modal fusion has four primary methods:early fusion,deep fusion,late fusion,and hybrid *** paper surveys the three majormulti-modal fusion technologies that can significantly enhance the effect of data fusion and further explore the applications of multi-modal fusion technology in various ***,it discusses the challenges and explores potential research ***-modal tasks still need intensive study because of data heterogeneity and *** complementary information and eliminating redundant information between modalities is critical in multi-modal *** data fusion methods may introduce extra noise and lead to worse *** paper provides a comprehensive and detailed summary in response to these challenges.

关键词： Multi-modal fusion representation translation alignment deep learning comparative analysis

RNA m6A dynamic modification mediated by nucleuslocalized FTO is involved in follicular reserve

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Zoological Research 2024年第2期45卷 415-428页

作者： jiao-Na Zhang Rui-Ting Wang Francesca-Gioia Klinger Shun-feng Cheng Wei Shen Xiao-feng Sun College of Life Sciences Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of ShandongQingdao Agricultural UniversityQingdaoShandong 266109China Department of Biomedicine and Prevention University of Rome Tor VergataRome 00133Italy

In eukaryotic organisms,the most common internal modification of messenger RNA(m RNA)is N6-methyladenosine(m6A).This modification can be dynamically and reversibly controlled by specific enzymes known as m6A writers and *** fat-mass and obesity-associated protein(FTO)catalyzes RNA demethylation and plays a critical role in various physiological and pathological *** research identified dynamic alterations in both m6A and FTO during the assembly of primordial follicles,with an inverse relationship observed for m6A levels and nuclear-localized FTO *** of Fto small interfering RNA(si RNA)altered the expression of genes related to cell proliferation,hormone regulation,and cell chemotaxis,and affected RNA alternative *** of the full-length Fto gene led to changes in m6A levels,alternative splicing of Cdk5,cell proliferation,cell cycle progression,and proportion of primordial ***,overexpression of Fto lacking a nuclear localization signal(NLS)did not significantly alter m6A levels or primordial follicle *** findings suggest that FTO,localized in the nucleus but not in the cytoplasm,regulates RNA m6A demethylation and plays a role in cell proliferation,cell cycle progression,and primordial follicle *** results highlight the potential of m6A and its eraser FTO as possible biomarkers and therapeutic targets.

关键词： m6A FTO Ovary Primordial follicle assembly Alternative splicing