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Microstructure evolution,mechanical properties and fracture behavior of Al-xsi/AZ91D bimetallic composites prepared by a compound casting

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Journal of Magnesium and Alloys 2024年第5期12卷 1944-1964页

作者： guangyu Li Wenming Jiang Feng guan Junwen Zhu Yang Yu Zitian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In this paper,the effect of the si content on microstructure evolution,mechanical properties,and fracture behavior of the Al-xsi/AZ91D bimetallic composites prepared by compound casting was investigated *** obtained results showed that all the Al-xsi/AZ91D bimetallic composites had a metallurgical reaction layer(MRL),whose thickness increased with increasing si content for the hypoeutectic Al-si/AZ91D composites,while the hypereutectic Al-si/AZ91D composites were *** MRL included eutectic layer(E layer),intermetallic compound layer(IMC layer)and transition region layer(T layer).In the IMC layer,the hypereutectic Al-si/AZ91D composites contained some si solid solution and flocculent Mg_(2)si+Al-Mg IMCs phases not presented in the hypoeutectic Al-si/AZ91D ***,increasing si content,the thickness proportion of the T layer increased,forming an inconsistent preferred orientation of the *** shear strengths of the Al-xsi/AZ91D bimetallic composites enhanced with increasing si content,and the Al-15si/AZ91D composite obtained a maximum shear strength of 58.6 MPa,which was 73.4% higher than the Al-6si/AZ91D *** fractures of the Al-xsi/AZ91D bimetallic composites transformed from the T layer into the E layer with the increase of the si *** improvement of the shear strength of the Al-xsi/AZ91D bimetallic composites was attributed to the synergistic action of the Mg_(2)si particle reinforcement,the reduction of oxidizing inclusions and the ratio of Al-Mg IMCs as well as the orientation change of the MRL.

关键词： Al/Mg bimetallic composites si content Mg_(2)si reinforcement Microstructure Mechanical properties Fracture behavior

Grating-free autofocus for single-pixel microscopic imaging

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Photonics Research 2024年第6期12卷 1313-1321页

作者： guan WANG HUAXIA DENG YU CAI MENGCHAO MA XIANG ZHONG XINGLONG GONG CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China School of Instrument Science and Opto-electronics Engineering Hefei University of TechnologyHefei 230009China

As a computational technology,single-pixel microscopic imaging(SPMI)transfers the target’s spatial information into a temporal *** traditional focusing method of imaging before evaluation is not applicable to the SPMI *** propose a grating-free autofocus strategy derived from the physical mechanism of optical *** the amplitude information of just one high-frequency point in the spectrum is all that is needed to achieve fast autofocus with the SPMI ***,only four patterns need to be cyclically projected,enabling efficient localization of the focal plane based on the measurement *** demonstrate SPMI autofocus experiments at micrometer and even nanometer depths of *** proposed method can be extended to achieve SMPI autofocus with invisible optical pattern illumination.

关键词： optical system illumination

The story of a decade:Genomics,functional genomics,and molecular breeding in Brassica napus

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Plant Communications 2024年第4期5卷 94-111页

作者： Jianwei Gu Zhilin guan Yushun Jiao Kede Liu Dengfeng Hong National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070HubeiChina College of Life Science and Technology Hubei Engineering UniversityXiaogan 432100 HubeiChina Wuhan Botanical Garden Chinese Academy of SciencesWuhan 430074 HubeiChina Yazhouwan National Laboratory Sanya 572024 HainanChina These authors contributed equally to this article.

Rapeseed(Brassica napus L.)is one of the major global sources of edible vegetable oil and is also used as a feed and pioneer crop and for sightseeing and industrial *** in genome sequencing and molecular marker technology have fueled a boom in functional genomic studies of major agronomic characters such as yield,quality,flowering time,and stress ***,introgression and pyra-miding of key functional genes have greatly accelerated the genetic improvement of important *** we summarize recent progress in rapeseed genomics and genetics,and we discuss effective molecular breeding strategies by exploring thesefindings in *** insights will extend our understanding of the molecular mechanisms and regulatory networks underlying agronomic traits and facilitate the breeding process,ultimately contributing to more sustainable agriculture throughout the world.

关键词： Brassica napus functional genomics genomics molecular breeding agronomic traits

Protein lysine crotonylation in cellular processions and disease associations

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Genes & Diseases 2024年第5期11卷 219-235页

作者： Hongling Zhao Yang Han Pingkun Zhou Hua guan Shanshan Gao Beijing Key Laboratory for Radiobiology Beijing Institute of Radiation MedicineBeijing 100850China

Protein lysine crotonylation(Kcr)is one conserved form of posttranslational modifications of proteins,which plays an important role in a series of cellular physiological and pathological *** e-amino groups are the primary sites of such modification,resulting in four-carbon planar lysine crotonylation that is structurally and functionally distinct from the acetylation of these *** levels of Kcr modifications have been identified on both histone and non-histone *** present review offers an update on the research progression regarding protein Kcr modifications in biomedical contexts and provides a discussion of the mechanisms whereby Kcr modification governs a range of biological *** addition,given the importance of protein Kcr modification in disease onset and progression,the potential viability of Kcr regulators as therapeutic targets is elucidated.

关键词： Cell biology Disease Lysine crotonylation Posttranslational modification Therapeutic target

Construction personnel dress code detection based on YOLO framework

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 709-721页

作者： Yunkai Lyu Xiaobing Yang Ai guan Jingwen Wang Leni Dai College of Information Engineering China Jiliang UniversityHangzhouChina College of Integrated Circuit Science and Engineering Nanjing University of Posts and TelecommunicationsNanjingChina China Jiliang University HangzhouZhejiangChina Department of Mathematics University of California San DiegoLa JollaCaliforniaUSA

It is important for construction personnel to observe the dress code,such as the correct wearing of safety helmets and reflective vests is conducive to protecting the workers'lives and safety of construction.A YOLO network-based detection algorithm is proposed for the construction personnel dress code(YOLO-CPDC).Firstly,Multi-Head Self-Attention(MHSA)is introduced into the backbone network to build a hybrid back-bone,called Convolution MHSA Network(CMNet).The CMNet gives the model a global field of view and enhances the detection capability of the model for small and obscured ***,an efficient and lightweight convolution module is *** is named Ghost Shuffle Attention-Conv-BN-siLU(GSA-CBS)and is used in the neck *** GSANeck network reduces the model size without affecting the ***,the sioU is used in the loss function and Soft NMS is used for *** results on the self-constructed dataset show that YOLO-CPDC algorithm has higher detection accuracy than current ***-CPDC achieves a mAP50 of 93.6%.Compared with the YOLOv5s,the number of parame-ters of our model is reduced by 18%and the mAP50 is improved by 1.1%.Overall,this research effectively meets the actual demand of dress code detection in construction scenes.

关键词： artificial intelligence computer vision deep learning deep neural networks

Numerical study on ignition start-up process of an underwater solid rocket motor across a wide depth range

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Chinese Journal of Aeronautics 2024年第10期37卷 136-157页

作者： Deyou WANG Shipeng LI Ge JIN Ruyao WANG Dian guan Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing System Design Institute of Electro-mechanic Engineering Beijing 100854China

Solid rocket motors have important applications in the propulsion of trans-media vehicles and underwater launched *** this paper,the ignition start-up process of an underwater solid rocket motor across a wide depth range has been numerically studied.A novel multi-domain integrated model has been developed by combining the solid propellant ignition and combustion model with the volume of fluid multiphase *** integrated model enables the coupled simulation of the propellant combustion and gas flow inside the motor,along with the gas jet evolution in the external water *** detailed flow field developments in the combustion chamber,nozzle,and wake field are carefully *** variation rules of the internal ballistics and thrust performance are also *** effects of environmental medium and operating depth on the ignition start-up process are systematically *** results show that the influence of the operating environment on the internal ballistic characteristics is primarily reflected in the initial period after the nozzle closure *** development of the gas jet in water lags significantly compared with that in *** the water depth increases,the ignition delay time of the motor is shortened,and the morphology evolution of the gas jet is significantly compressed and ***,the necking and bulging of the jet boundary near the nozzle outlet and the consequent shock oscillations are intensified,resulting in stronger fluctuations in the wake pressure field and motor thrust.

关键词： Underwater propulsion Solid rocket motor Ignition start-up process Underwater gas jet Thrust oscillation

Analysis of conductance and interfacial polarisation behaviours of silicone rubber based on frequency domain spectroscopy

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High Voltage 2024年第1期9卷 56-65页

作者： Hao Hu Zhidong Jia Xilin Wang Ruiyang guan Weinan Fan simin Luo Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhenChina guangzhou Power Supply China Southern Power Grid Company Ltd.GuangzhouChina

silicone rubber(SR)is widely used for cable insulation and operates in multi-stress coupling *** dielectric properties and ageing performance are the essential factors affecting cable *** this study,the frequency domain spectroscopy of unaged SR and SR aged under various conditions is *** dielectric responses before and after ageing are analysed in depth by the conjoint analysis via multiple complex planes(permittivity,conductivity,and modulus).Typical conductivity and interfacial polarisation properties,as well as property changes resulting from thermal and tensile ageing,are *** results show that tensile ageing promotes conductance and interfacial polarisation,while thermal ageing shows the opposite *** on the multi-core model and charge carrier hopping transport model,thermal and tensile ageing mechanisms on the conductance and interfacial polarisation behaviours of SR are *** behaviours exhibit positively correlated changing characteristics,suggesting that the two behaviours may originate from a common *** carrier transport process,promoted by the tensile effect and slightly suppressed by the thermal effect,is the primary factor and considered an important indicator to evaluate the dielectric properties of SR insulation.

关键词： interfacial rubber insulation

Degradation of iopamidol in the permanganate/sulfite process:Evolution of iodine species and effect on the subsequent formation of disinfection by-products

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Journal of Environmental Sciences 2024年第1期135卷 345-352页

作者： Yimin Lin Hongyu Dong Yating Zhu Gongming Zhou Junlian Qiao Xiaohong guan State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Department of Environmental Science School of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Permanganate/sulfite(Mn(VII)/S(IV))process is a promising pre-oxidation technology for sequestering the emerging organic contaminants in drinking water treatment ***(IPM),a representative of iodinated X-ray contrast media,has been widely detected in water sources and has the risk of forming iodinated disinfection byproducts(I-DBPs)in water treatment *** this study,we investigated the evolution of iodine species during the IPM degradation by the Mn(VII)/S(IV)process and its effect on the subsequent formation of I-DBPs during chlorination at pH 7.0 and *** could be effectively degraded in the Mn(VII)/S(IV)process at environmentally relevant pH(pH 7.0 and 8.0).The results of quenching and competitive oxidation kinetic experiments revealed that SO^(·-)_(4)was the major reactive oxidizing species contributing to the degradation of IPM whereas the contributions of HO·and reactive manganese species were negligible in the Mn(VII)/S(IV)process.I–and IO–3were generated while no HOI was detected during the degradation of IPM in the Mn(VII)/S(IV)*** effects of IPM oxidation by Mn(VII)/S(IV)on the subsequent formation of chlorinated disinfection by-products(Cl-DBPs)during chlorination were related to the category of *** pre-oxidation of IPM by Mn(VII)/S(IV)resulted in the generation of I-DBPs during the disinfection process although no I-DBPs were detected if no pre-oxidation was *** finding of this study suggested that attention should be paid to the toxicity of DBPs when water containing iodinated organic contaminants is treated by Mn(VII)/S(IV)process or other pre-oxidation technologies.

关键词： Permanganate/sulfite Iopamidol Sulfate radical Iodinated disinfection byproducts Pre-oxidation

基于相位同步动力学重构网络单纯复形的相互作用

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物理学报 2024年第12期73卷 78-88页

作者：罗恺明管曙光邹勇华东师范大学物理与电子科学学院上海200241

复杂网络的高阶相互作用,如单纯复形和超边等,已经成为了研究的热点.本文提出一种基于节点同步动力学的特性来重构网络的单纯复形结构的新方法.通过分析Kuramoto-Sakaguchi模型中节点相位的时间序列同步性,建立了网络拓扑结构的解析描述... 详细信息

复杂网络的高阶相互作用,如单纯复形和超边等,已经成为了研究的热点.本文提出一种基于节点同步动力学的特性来重构网络的单纯复形结构的新方法.通过分析Kuramoto-Sakaguchi模型中节点相位的时间序列同步性,建立了网络拓扑结构的解析描述,实现了对网络结构的精确辨识.该方法的核心在于,运用理论手段推导得到了拉普拉斯矩阵与线性化Kuramoto-Sakaguchi系统相位之间的解析联系.这一联系不仅具有强大的普适性,而且能够有效地应用于识别包含任意阶单纯复形相互作用的网络结构.本文的研究进一步表明,这种解析关系能够用于鉴别网络中的对称节点,并且通过数值模拟证实了间接相互作用节点之间发生遥同步的现象与网络结构的对称性有着密切的联系.这些发现为深入理解网络的结构特性和动力学行为提供了新的理论工具和视角.

关键词：复杂网络单纯复形相位同步高阶相互作用