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Recent Advances in Nickel Catalyzed Carbonylative Reactions via the Insertion of Carbon Monoxide

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Chinese Journal of Chemistry 2024年第2期42卷 177-189页

作者： Xinzhou chen Gang chen Zhong lian Department of Dermatology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug ***,they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom ***-metal-catalyzed carbonylation via the insertion of co is one of the most efficient and straightforward strategies to access carbonyl ***,most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal ***,there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of *** with the well-established palladium-catalyzed carbonylative reactions,nickel-catalyzed analogous transformations have been relatively *** is primarily because CO strongly binds to nickel,often resulting in catalyst *** recent years,some research groups have focused on using CO surrogates or NN_(2) pincer nickel catalyst to circumvent the formation of Ni(CO)_(4).Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds,such as ketones,carboxylic acids,thioesters,acyl chloride and carboxamides.

关键词： Carbonylation Nickel catalysis Carbon monoxide C1 chemistry Carbonyl-containing compounds

Recent advances in fabrication and functions of neuromorphic system based on organic field effect transistor

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International Journal of Extreme Manufacturing 2024年第2期6卷 273-295页

作者： Yaqian Liu Minrui lian Wei chen Huipeng chen School of Physics and Electronic Engineering Zhengzhou University of Light IndustryHenan 450002People’s Republic of China Institute of Optoelectronic Display National&Local United Engineering Lab of Flat Panel Display TechnologyFuzhou UniversityFuzhou 350002People’s Republic of China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207People’s Republic of China Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore Department of Physics National University of Singapore3 Science Drive 3Singapore 117543Singapore

The development of various artificial electronics and machines would explosively increase the amount of information and data,which need to be processed via in-situ *** synapse devices can store and process signals in a parallel way,thus improving fault tolerance and decreasing the power consumption of artificial *** organic field effect transistor(OFET)is a promising component for bioinspired neuromorphic systems because it is suitable for large-scale integrated circuits and flexible *** this review,the organic semiconductor materials,structures and fabrication,and different artificial sensory perception systems functions based on neuromorphic OFET devices are ***,a summary and challenges of neuromorphic OFET devices are *** review presents a detailed introduction to the recent progress of neuromorphic OFET devices from semiconductor materials to perception systems,which would serve as a reference for the development of neuromorphic systems in future bioinspired electronics.

关键词： organic field effect transistor neuromorphic systems synaptic transistor sensory perception systems device fabrication

A Novel Multi-Stream Fusion Network for Underwater Image Enhancement

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China Communications 2024年第2期21卷 166-182页

作者： Guijin Tang lian Duan Haitao Zhao feng Liu Jiangsu Key Laboratory of Image Processing and Image Communication Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

Due to the selective absorption of light and the existence of a large number of floating media in sea water, underwater images often suffer from color casts and detail blurs. It is therefore necessary to perform color correction and detail restoration. However,the existing enhancement algorithms cannot achieve the desired results. In order to solve the above problems, this paper proposes a multi-stream feature fusion network. First, an underwater image is preprocessed to obtain potential information from the illumination stream, color stream and structure stream by histogram equalization with contrast limitation, gamma correction and white balance, respectively. Next, these three streams and the original raw stream are sent to the residual blocks to extract the features. The features will be subsequently fused. It can enhance feature representation in underwater images. In the meantime, a composite loss function including three terms is used to ensure the quality of the enhanced image from the three aspects of color balance, structure preservation and image smoothness. Therefore, the enhanced image is more in line with human visual ***, the effectiveness of the proposed method is verified by comparison experiments with many stateof-the-art underwater image enhancement algorithms. Experimental results show that the proposed method provides superior results over them in terms of MSE,PSNR, SSIM, UIQM and UCIQE, and the enhanced images are more similar to their ground truth images.

关键词： image enhancement multi-stream fusion underwater image

Clarifying effect of welding conditions on microstructure and mechanical properties of friction stir spot-welded DH590 automotive high-strength steel plates

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Journal of Iron and Steel Research International 2021年第2期28卷 232-243页

作者： Ya-peng Zhao lian-feng chen Shi-jie Zhu Yu-feng Sun Shao-kang Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanChina Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou UniversityZhengzhou 450001HenanChina Beijing Shougang Co. Ltd.Beijing 100041China

Friction stir spot welding was successfully applied to the 1.2-mm-thick DH590 dual-phase steel plates by using a polycrystalline cubic boron nitride rotating *** welding,the rotation speed ranged from 600 to 1000 r/min and the penetration depth ranged from 0.1 to 0.3 *** the spot joints,the size of the stir zone increased with the increase in rotation speed as well as the penetration depth of the *** with the banded ferrite and martensite structure of the base metal,a mixed microstructure of ferrite and tempered martensite,refined bainite structure and coarse martensite structure were found in the heat-affected zone,thermomechanically affected zone and stir zone of the joints,*** kinds of interfacial shapes were formed between the upper and lower steel plates,and the formation of the bonded interface was dominated mainly by the penetration depth of the rotating tool rather than the rotation *** was revealed that the joints with straight interfaces showed higher shear tensile loads comparing with those with hook-like *** tensile tests showed that the maximum shear tensile load reached about 15.56 kN when the rotation speed and penetration depth were set as 800 r/min and 0.3 mm,*** specimen was fractured through plug failure mode with a total elongation of about 5.6 mm.

关键词： Friction stir spot welding DH590 dual-phase steel Microstructure Joint strength Microhardness

A condition-based maintenance policy for reconfigurable multi-device systems

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Advances in Manufacturing 2024年第2期12卷 252-269页

作者： Shu-lian Xie feng Xue Wei-Min Zhang Jia-Wei Zhu School of Mechanical Engineering Tongji UniversityShanghai201804People’s Republic of China

The exploration of component states for optimizing maintenance schedules in complex systems has garnered significant interest from ***,current literature usually overlooks the critical aspects of system flexibility and *** implementation of system reconfiguration can effectively mitigate system downtime and enhance production *** study proposes a dynamic condition-based maintenance policy considering reconfiguration for reconfigurable systems.A double-layer decision rule was constructed for the devices and *** achieve the best overall maintenance effect of the system,the remaining useful life probability distribution and recommended maintenance time of each device were used to optimize the concurrent maintenance time window of the devices and determine whether to reconfigure them.A comprehensive maintenance efficiency index was introduced that simultaneously considered the maintenance cost rate,reliability,and availability of the system to characterize the overall maintenance *** reconfiguration cost was included in the maintenance *** proposed policy was tested through numerical experiments and compared with different-level *** results show that the proposed policy can significantly reduce the downtime and maintenance costs and improve the overall system reliability and availability.

关键词： Condition-based maintenance(CBM) Reconfigurable system Remaining useful life Maintenance cost System reliability

Method for the height measurement of agricultural implements based on variable parameter Kalman filter

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 193-199页

作者： Gaolong chen Xiwen Luo lian Hu Pei Wang Jie He Dawen feng Weicong Li Jinkang Jiao College of Engineering South China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China Guangdong Provincial Key Laboratory of Agricultural Artificial Intelligence(GDKL-AAI) Guangzhou 510642China

To improve the GNSS receiver’s accuracy,continuity,and stability in measuring the height of agricultural implements,this study proposed a variable-parameter Kalman filter(VPKF)algorithm based on GNSS and accelerometer to estimate the height of the implements *** VPKF was verified,and its accuracy was evaluated by parallel rail platform and field *** the parallel rail test results,when the GNSS receiver was in real-time kinematic(RTK)positioning and the time delay of differential correction data(TDDCD)was less than or equal to 4 s,the root mean square error(RMSE)of the VPKF estimation was 9.82 *** RMSE of the GNSS measurement was 18.85 *** the GNSS receiver lost differential correction data within 28 s,the absolute error of VPKF was less than 30 mm,and the RMSE was 16.93 *** field test results showed that when the GNSS receiver was in RTK positioning and the TDDCD was less than or equal to 4 s,the RMSE of VPKF estimation was 13.43 mm,and the GNSS measurement was 14.56 *** the GNSS receiver lost differential correction data within 28 s,the RMSE of the VPKF estimate was 15.22 *** results show that VPKF can optimally estimate implement height with better ***,the VPKF can obtain a more accurate,continuous,and stable height of the implement,and increase the application scenarios of the GNSS receiver to measure the implement height.

关键词： agricultural implement height Kalman filter GNSS accelerometer

Impact of short-term ambient air pollution exposure on the risk of severe COVID-19

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Journal of Environmental Sciences 2024年第1期135卷 610-618页

作者： Baihuan feng Jiangshan lian Fei Yu Dan Zhang Weizhen chen QiWang Yifei Shen Guoliang Xie Ruonan Wang Yun Teng Bin Lou Shufa Zheng Yida Yang Yu chen Department of Laboratory Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China Key Laboratory of Clinical In Vitro Diagnostic Techniques of Zhejiang Province Hangzhou 310000China Institute of Laboratory Medicine Zhejiang UniversityHangzhou 310000China Department of Infectious Diseases The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious Diseasesthe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China

Ecological studies suggested a link between air pollution and severe COVID-19 outcomes,while studies accounting for individual-level characteristics are *** the present study,we aimed to investigate the impact of short-term ambient air pollution exposure on disease severity among a cohort of 569 laboratory confirmed COVID-19 patients admitted to designated hospitals in Zhejiang province,China,from January 17 to March 3,2020,and elucidate the possible biological processes involved using *** with mild cases,severe cases had higher proportion of medical conditions as well as unfavorable results in most of the laboratory tests,and manifested higher air pollution exposure *** exposure to air pollutants was associated with increased risk of severe COVID-19 with odds ratio(OR)of 1.89(95%confidence interval(CI):1.01,3.53),2.35(95%CI:1.20,4.61),2.87(95%CI:1.68,4.91),and 2.01(95%CI:1.10,3.69)for PM_(2.5),PM_(10),NO_(2)and CO,*** for NO_(2)remained significant in two-pollutant models after adjusting for other *** analysis showed 884 differentially expressed genes which mainly were enriched in virus clearance related biological processes between patients with high and low NO_(2)exposure levels,indicating that compromised immune response might be a potential underlying mechanistic *** findings highlight the impact of shortterm air pollution exposure,particularly for NO_(2),on COVID-19 severity,and emphasize the significance in mitigating the COVID-19 burden of commitments to improve air quality.

关键词： Air pollution COVID-19 Severity Transcriptomics Immune response

Morphogenesis and Molecular Phylogeny of a Marine Urostylid Ciliate Apokeronopsis wrighti(Protista, Ciliophora, Hypotrichia)

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Journal of Ocean University of China 2024年第4期23卷 1067-1075页

作者： lian Chunyu LI Ping ZHANG Tengteng SHAO chen Department of Zoology College of Life SciencesShaanxi Normal UniversityXi’an 710119China Powerchina Northwest Engineering Corporation Limited Xi’an 710065China

Hypotrichs are one of the highly differentiated ciliated lineages which play important roles in ecological, environmental,evolutionary and basic biological studies. In the present study, we investigated the living characteristics, infraciliature, nuclear apparatus, ontogenesis and phylogenetic position of a marine hypotrichous ciliate, Apokeronopsis wrighti Long et al., 2008, which was isolated from coastal waters in Shenzhen, China. The new isolate resembles the type population in terms of morphological characteristics, morphometrics, and SSU rRNA gene sequence that is with a 99.7% similarity. Ontogenesis of A. wrighti is characterized by oral primordium for the proter as well as marginal and dorsal kineties anlagen in both filial products formed de novo, and the cirral row arranged along the paroral and endoral arises from several anterior frontoventral-transverse cirral streaks. Phylogenetic analyses based on SSU and concatenated gene data suggest that five species of Apokeronopsis form a monophyletic clade, and the genus Apokeronopsis is closely related to Thigmokeronopsis and Metaurostylopsis.

关键词： 18S rRNA gene Apokeronopsis ciliated protists multi-gene ontogenesis systematics Urostylida

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-feng Zhou Yu Long Yan-liang Yi cheng Deng lian-Xi Hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding