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Rare Metals 2024年第9期43卷 4387-4400页

作者： Ao Xia Jia-Guang Zheng Qing-Bo Zhang yu-gang shu Cheng-Guo Yan Liu-Ting Zhang Zhan-Liang Tao Li-Xin Chen School of Energy and Power Jiangsu University of Science and Technology Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and EngineeringZhejiang University

The facile construction of nanoscale NbHxsupported by Ti3C2（NbHx@Ti3C2） was achieved using facile ball milling strategy to improve the hydrogen desorption kinetics and reversibility of magnesium borohydride (Mg（BH4）2).The doping of 30 wt%NbHx@Ti3C2catalyst reduced the onset dehydrogenation temperature of Mg（BH4）2to 71.2℃.Additionally,the Mg（BH4）2+30NbHx@Ti3C2composite achieved remarkable hydrogen release of over 9.2 wt% at a temperature as low as 230℃,indicating unexpected dehydrogenation ***,the reversibility of NbHx@Ti3C2doped Mg（BH4）2was retained to more than 4.2 wt%after four cycles,which was increased by 68% compared to that of undoped Mg（BH4）*** strong catalysis of NbHx@Ti3C2catalyst could be attributed to the synergistic effect of NbHxand Ti3C2in hydrogen spillover and *** as a??hydrogen pump??for effective hydrogen spillover,while Ti3C2created numerous diffusion channels for hydrogen dissolution and provided the active catalytic site to facilitate the re/dehydrogenation of Mg（BH4）2.

关键词： Catalysts Hydrogen storage Magnesium borohydride Mxene

Visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)

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Chinese Chemical Letters 2024年第7期35卷 281-284页

作者： Tian-yu Gao Xiao-Yan Mo shu-Rong Zhang yuan-Xu Jiang shu-Ping Luo Jian-Heng Ye Da-gang yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are obtained in moderate to high yields under mild conditions. This protocol shows noteworthy functionalgroup compatibility, high chemo-and regioselectivities under transition-metal-free conditions with an inexpensive organo-dye as photosensitizer. Mechanistic studies indicate that the benzylic carbanion is generated as an intermediate via the sequential single electron transfer(SSET) process.

关键词： Carbon dioxide Epoxides Visible-light photoredox catalysis Hydroxy acid Sequential single electron transfer

Comparative analysis of the microbiome of sympatric wintering Bean Geese,Domestic Ducks,humans,and soil at Shengjin Lake of China reveals potential public risk to human health

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Avian Research 2024年第2期15卷 279-286页

作者： gang Liu Na Xu Chongyang yu College of Life Sciences Anhui Medical UniversityHefei 230032China

The gut microbiota of migratory waterbirds is affected by various complex factors,including cross-species transmission,which increases the risk of pathogen spreading among sympatric animals and poses a potential public health risk to *** this study,we investigated the microbial communities of wintering Bean Geese(Anser fabalis),Domestic Ducks(*** domesticus),humans,and soil using high-throughput sequencing of the 16S rRNA gene region in Shengjin Lake,*** total,6,046,677 clean reads were obtained,representing 41,119 operational taxonomic units(OTUs)across the four *** dominant microbial phyla were the Proteobacteria,Firmicutes,Bacteroidota,and *** Sorensen similarity index and alpha and beta diversity results showed that the gut microbial communities of Bean Geese and Domestic Ducks were more similar to those of the other *** analysis revealed that Faecalibacterium prausnitzii,Pseudomonas fragi,and Bradyrhizobium elkanii were hubs of the three major *** common microbiomes were iden-tified in Bean Geese,Domestic Ducks,humans,and soil in Shengjin Lake.A total of 96 potential pathogens were identified among the four groups,with 20 specific potentially pathogenic microbiomes found in the gut of Bean *** of these pathogens are responsible for significant financial losses in the poultry industry and pose risks to human *** pneumoniae,Morganella morganii,Escherichia coli,and Ralstonia insidiosa are potential core pathogens found in the four groups at Shengjin Lake that can cause diseases in humans and an-imals and facilitate cross-species transmission through various ***,humans are at risk of con-tracting these pathogens from migratory birds because of their frequent contact with domestic ***,further studies are required to explore the potential pathogenic species and transmission pathways among sympatric wintering Bean Geese,Domestic Ducks,humans,and soil.

关键词： Microbiome Migratory waterbird Pathogens Poultry Sympatric species

Progress on the glassy-crystal laminates:From design,microstructure to deformation and future solutions

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Journal of Materials Science & Technology 2024年第5期172卷 113-144页

作者： yu Chen Ronggao Cui Jun Shen gang Wang College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Motor Design Business Weichai New Energy Technology Co.Ltd.Weifang 261061China Guangdong Key Laboratory of Electromagnetic Control and Intelligent Robots Shenzhen UniversityShenzhen 518060China Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200444China

The development of new design strategies to create innovative structural materials,refine existing ones,and achieves compatible combinations of strength and plasticity remains a worldwide *** alloys,such as shape memory alloys(SMAs),bulk metallic glasses(BMGs),high entropy alloys(HEAs),and heterogeneous pure metals such as Cu,have excellent mechanical responses,but they still fall short of meeting all the requirements of structural materials due to specific flaws,such as lack of tensile de-formation for BMGs and low yielding strength for *** address these shortcomings,proposals such as integrating glassy matrices and crystallized alloys,such as HEAs/SMAs,have been ***,these solutions have unresolved issues,such as the challenging control of B2 phase formation in BMG ***,glass-crystal(A/C)laminated alloys with alternating layers have been reported to exhibit improved mechanical properties and activated work-hardening behaviors,but they still face press-ing issues such as bonding interfaces and unknown deformation *** review focuses on design routes such as the selection of alloy components and processing techniques,exploration of micro-structural evolution and deformation modes with an increase in strain,and future solutions to address pressing and unsolved *** prominent advantages include diversified deformation mechanisms,such as deformation twinning,martensitic phase transformation,and precipitation hardening,as well as tuned interactive reactions of shear bands(SBs)near the A/C ***,this review provides a promising pathway to design and develop structural materials in the materials field community.

关键词： Glassy-crystal laminates Bulk metallic glasses High entropy alloys Shape memory alloys Microstructure Deformation mechanisms Future solutions

State-sensitive convolutional sparse coding for potential biomarker identification in brain signals

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Science China(Information Sciences) 2024年第5期67卷 270-286页

作者： Puli WANG yu QI gang PAN College of Computer Science and Technology Zhejiang University State Key Laboratory of Brain-Machine Intelligence Zhejiang University MOE Frontier Science Center for Brain Science and Brain-machine Integration Zhejiang University Affiliated Mental Health Center & Hangzhou Seventh People's Hospital Zhejiang University School of Medicine

The identification of prototypical waveforms, such as sleep spindles and epileptic spikes, is crucial for the diagnosis of neurological disorders. These prototypical waveforms are usually recurrently presented in certain brain states, serving as potential biomarkers for clinical evaluations. Convolutional sparse coding(CSC) approaches have demonstrated strength in identifying recurrent patterns in time-series. However,existing CSC approaches do not explicitly explore state-specific patterns, making it difficult to identify state-related biomarkers. To address this problem, we propose state-sensitive CSC to learn state-specific prototypical waveforms. Specifically, we model signals of a certain state with specific waveforms that only appear frequently in this state and background waveforms that are independent of states. Based on this,state-sensitive CSC separates state-specific waveforms from background ones explicitly by incorporating incoherence constraints into optimizations. Experiments with epilepsy brain signals demonstrate that our approach can effectively identify prototypical waveforms in pre-ictal states, providing potential biomarkers for seizure prediction. Our approach provides a promising tool for automatic biomarker candidate identification.

关键词： convolutional sparse coding prototypical waveforms state-specific dictionary biomarker identification neural signal processing

Is Yang-Mills theory unitary in fractional spacetime dimensions?

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 59-64页

作者： Qingjun Jin Ke Ren gang Yang Rui yu Graduate School of China Academy of Engineering Physics Beijing 100193China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Hangzhou 310024China School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China Beijing Computational Science Research Center Beijing 100193China

We present concrete evidence that Yang-Mills theory exhibits non-unitarity in non-integer spacetime *** violation of unitarity stems from evanescent operators that,while vanishing in four dimensions,are non-zero in general d *** demonstrate that these evanescent operators lead to the emergence of both negative-norm states and complex anomalous dimensions.

关键词： gauge field theories field theories in dimensions other than four renormalization

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Efficacy and safety of Yangxue Qingnao Granules in treatment of migraine:A systematic review and meta-analysis

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World Journal of Clinical Cases 2024年第2期12卷 335-345页

作者： Bo Zhou Gui-shu Wang yu-Ning Yao Tong Hao Huan-Qin Li Ke-gang Cao Department of Neurology Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing 100091China Department of Infectious Disease Dongfang HospitalBeijing University of Chinese MedicineBeijing 100078China Institute for Brain Disorders Beijing University of Chinese MedicineBeijing 100700China Department of Acupuncture and Moxibustion Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical UniversityBeijing 100010China

BACKGROUND Yangxue Qingnao Granules(YXQN)is a Chinese patent medicine that has been commonly used in the clinical treatment of *** To assess the efficacy and safety of YXQN alone for the treatment of *** We searched 10 databases to identify relevant randomized controlled trials(RCTs)published before September *** review authors independently searched and screened the literature,extracted the data,and assessed the methodological quality of the studies using criteria from ROB 2.0,and analyzed the data using Review Manager 5.4 *** A total of 12 RCTs including 767 participants with migraine met the selection *** divided these studies into comparisons of YXQN with placebo,routine treatment drugs,and other Chinese patent *** meta-analysis showed the following:(1)Efficacy:The YXQN group outperformed the placebo group[relative risk(RR)=0.29,95%confidence interval(95%CI):0.15–0.43,P<0.00001],routine treatment group(RR=0.18,95%CI:0.09–0.27,P<0.0001),and Chinese patent medicine group(RR=0.27,95%CI:0.13–0.41,P<0.001);(2)frequency of headache:There was a significant difference between YXQN vs placebo[mean difference(MD)=-1.25,95%CI:-1.60 to-0.90,P<0.00001],routine treatment drugs(MD=-0.85,95%CI:-1.15 to-0.56,P<0.00001),and Chinese patent medicine(MD=-0.91,95%CI:-1.35 to-0.46,P<0.0001);(3)headache duration:We found great heterogeneity between studies,with no differences between YXQN and placebo(MD=-0.61,95%CI:-1.53 to-0.31,P=0.19)and routine treatment drugs(MD=-0.22,95%CI:-0.89 to 0.46,P<0.53).YXQN was more effective than other Chinese patent medicines in reducing headache duration(MD=-1.24,95%CI:-1.70 to-0.77,P<0.00001);and(4)headache severity:There was no significant difference between YXQN vs placebo(MD=-1.67,95%CI:-3.52 to 0.19,P=0.08),routine treatment drugs(MD=-0.53,95%CI:-2.02 to 0.96,P=0.68),and other Chinese patent medicines(MD=-0.49,95%CI:-2.83 to 1.85,P=0.68).Mild gastrointestinal adverse reactions were reported

关键词： Meta-analysis Migraine Yangxue Qingnao Granules Traditional Chinese patent medicine

Navigating the Challenges of Emerging Contaminants to Protect Human and Ecological Health

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Engineering 2024年第6期37卷 1-2页

作者： Jiuhui Qu Michael R.Hoffmann gang yu School of Environment Tsinghua UniversityBeijing 100084China Linde-Robinson Laboratories California Institute of TechnologyPasadenaCA 91125USA Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal UniversityZhuhai 519000China

Emerging contaminants are defined as chemicals that are not currently(or have only recently been)regulated and about which there are concerns regarding their impact on human or ecological *** contaminants are widely detected in air,water,soil,sediment,and biotic *** is against this backdrop of urgency that we have curated this special issue titled“Emerging Contaminants Control:Science and Technology,”with the goal of uniting the latest scientific insights and pioneering strategies to address this global *** special issue embarks on a comprehensive examination of the emerging contaminants dilemma,covering aspects such as risk assessment,remediation technologies,environmental surveying,and the broader implications for *** a collection of articles,we probe deep into the core of this issue,showcasing studies that range from appraising environmental risks to forging new methods for treatment and scrutinizing the occurrence of contaminants across different environmental settings.

关键词： Ecological surveying environmental

Density-based ship detection in SAR images:Extension to a self-similarity perspective

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Chinese Journal of Aeronautics 2024年第3期37卷 168-180页

作者： Xueqian WANG gang LI Zhizhuo JIANG yu LIU You HE Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China

Nonlocal self-similarity is an important property of Synthetic Aperture Radar(SAR)images to characterize the repetitiveness of features embodied by SAR images within nonlocal areas and has been used for enhancement of SAR *** SAR ship detectors often independently handle small sub-images cropped from a large marine SAR image and do not exploit the nonlocal self-similarity *** this paper,we propose a new ship detector from the perspective of nonlocal self-similarity in SAR images to improve the ship detection performance,basically including three stages:prescreening,intra-cue calculation,and inter-cue *** the prescreening stage,we design a new Histogram-based Density(HD)feature to rapidly select candidate sub-images potentially containing ship targets from a large SAR *** the intra-cue calculation stage,target cues within a single candidate sub-image are *** the inter-cue calculation stage,thanks to the nonlocal self-similarity among different candidate sub-images in terms of density features,we innovatively extract a weighted superpixel-HD map to obtain accumulated intracues across all the candidate ***,for each candidate sub-image,we fuse its inter-cue and intra-cue to obtain final detection *** results based on real SAR images show that our newly proposed method provides a better target-to-clutter contrast and ship detection performance than those of other state-of-the-art detection approaches.

关键词： Ship detection Synthetic aperture radar(SAR) Density Self-similarity Histogram

High corrosion and wear resistant electroless Ni–P gradient coatings on aviation aluminum alloy parts

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 155-164页

作者： Bo Wang Jiawei Li Zhihui Xie Gengjie Wang gang yu College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410012China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province/College of Chemistry and Chemical Engineering China West Normal UniversityNanchong 637002China Zhongchuan Machinery Ltd.Co. Aero Engine Corporation of ChinaChangsha 410200China

A Ni–P alloy gradient coating consisting of multiple electroless Ni–P layers with various phosphorus contents was prepared on the aviation aluminum alloy. Several characterization and electrochemical techniques were used to characterize the different Ni–P coatings’ morphologies, phase structures, elemental compositions, and corrosion protection. The gradient coating showed good adhesion and high corrosion and wear resistance, enabling the application of aluminum alloy in harsh environments. The results showed that the double zinc immersion was vital in obtaining excellent adhesion (81.2 N). The optimal coating was not peeled and shredded even after bending tests with angles higher than 90°and was not corroded visually after 500 h of neutral salt spray test at 35℃. The high corrosion resistance was attributed to the misaligning of these micro defects in the three different nickel alloy layers and the amorphous structure of the high P content in the outer layer. These findings guide the exploration of functional gradient coatings that meet the high application requirement of aluminum alloy parts in complicated and harsh aviation environments.

关键词： aluminum alloy electroless nickel coating corrosion adhesion