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An Evaluation of the Infection Status and Source of Subgroup J Avian Leukosis Virus in Cloned Free-Range Layers

Journal of Integrative Agriculture 2013年第4期12卷 687-693页

作者： ZHANG Pei-pei LIU Shao-qiong WANG Jian WANG Bo zhao cheng-di ZHANG Yong-guang SUN Shu-hong College of Veterinary Medicine Shandong Agricultural University Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences

In recent years, subgroup J avian leukosis virus （ALV-J） has been found to frequently infect layers in China. This virus is responsible for economic losses due to both mortality and decreased performance in chickens. In this study, 45-d-old cloned flee-range layers were suspected to be infected with ALV and other immunosuppressive diseases because their feathers were unkempt and their growth rate was impaired. To estimate the infection status and determine the source of ALV-J in the flock, 30 cloacal swabs were randomly collected to measure the p27 antigen level by enzyme-linked immunosorbent assay （ELISA）. Among the birds that were tested, 87% （26/30） were positive. In addition, 6 anticoagulant blood samples were aseptically collected at random from the flock when the layers were 60 d old. These samples were centrifuged to obtain the leukocytes, which were then used to inoculate chicken embryo fibroblast （CEF） cells for the identification of ALV-J by indirect immunofluorescence （IFA）. Of the samples tested, 100% （6/6） were positive. The flock＇s production performance was also investigated, and 10 layers were necropsied to evaluate pathological changes at 115 d of age. The flock never laid eggs even though they reached the age of the first laying （110 d）. Furthermore, there were pathological changes present, including atrophy of the thymus and bursa of Fabricius, undeveloped ovaries, glandular stomach haemorrhage, and hepatosplenomegaly. Paraffin-embedded sections of intumescent liver and spleen were prepared for antigen localisation using IFA. Positive signals were prevalent in paraffin-embedded sections of the intumescent liver and spleen. Furthermore, provirus DNA was extracted from 4 cloned flee-range layers, and 2 patemal parents （HR native cocks）, and the gp85 gene of ALV-J was amplified by PCR to analyse the genetic variation. The results of the autogenous variation analysis showed that the 6 strains were 98.5-99.7% homologous. This study indicated that there

关键词： cloned free-range layers ALV-J infection status hereditary variation source exploration

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Nonlinear optics of two-dimensional heterostructures

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Frontiers of physics 2024年第3期19卷 19-27页

作者： Xiangkun Zeng Chenyu Wan Zhichen zhao di Huang Zhanshan Wang Xinbin cheng Tao Jiang MOE Key Laboratory of Advanced Micro-Structured Materials Shanghai Frontiers Science Center of Digital OpticsInstitute of Precision Optical Engineeringand School of Physics Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 200092China

Two-dimensional (2D) materials exhibit exceptionally strong nonlinear optical responses, benefiting from their reduced dimensionality, relaxed phase-matching requirements, and enhanced light-matter interaction. With additional degrees of freedom in the modulation of the physical properties by stacking 2D layers together, nonlinear optics of 2D heterostructures becomes increasingly fascinating. In this perspective, we provide a brief overview of recent advances in the field of nonlinear optics of 2D heterostructures, with a particular focus on their remarkable capabilities in characterization and modulation. Given the recent advances and the emergence of novel heterostructures, combined with innovative tuning knobs and advanced nonlinear optical techniques, we anticipate deeper insights into the underlying mechanisms and more associated applications in this rapidly evolving field.

关键词： nonlinear optics 2D heterostructures

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Evolution of inner wall wrinkle defects in the sinking zone of a thick-walled steel tube during radial forging

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Advances in Manufacturing 2024年第2期12卷 396-408页

作者： Yu-zhao Yang cheng Xu Li-Xia Fan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

An axial wrinkle defect was observed in the inner wall of the sinking zone of a thick-wall steel tube processed by cold radial *** can evolve into *** present study focuses on the evolution of wrinkles and the effects of process parameters on them using a three-dimensional radial forging process finite element model,radial forging experiments,and surface morphology *** results indicated that the vertical section angle of the hammer die and the size of the tube blank significantly affect the evolution of *** height-to-width ratioλwas introduced to describe the morphology of *** had an approximately linear relationship with the radius reduction in the sinking *** was a linear correlation between the growth slope ofλand the axial to circumferential strain ratio|εr/εθ|,which can predict theλunder few process *** the 30SiMn2MoVA steel,at the junction of the forging and sinking zones,the threshold ofλof the wrinkle that can evolve into a fissure is approximately 1.123.

关键词： Radial forging Inner wall Wrinkle defects Evolution Sinking zone

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Investigation of cracking mechanism of the first tunnel lining during double-arch tunnel construction

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Underground Space 2024年第1期14卷 1-17页

作者： Yi Sui Xiaohui cheng Zuozhou zhao Weibin Ma Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China School of Civil Engineering Tsinghua UniversityBeijing 100084China

To solve the engineering problem of the first tunnel lining cracking caused by the second tunnel construction of double-arch highway tunnels,a research method combining distributed optical-fibre monitoring,inversion analysis and numerical simulation that can reflect lining cracking was *** fibres were laid on opposite sides of the steel arches inside the first tunnel *** optical-fibre monitoring was conducted continuously during the second tunnel *** on the fibre-optic strain profile,the lining cracking was deduced and warned in *** mechanical behaviour of the steel arch was investigated by the inversion analysis,which took into consideration the integrated impact of axial force and flexural moment.A two-dimensional(2D)load-structure method–based numerical model was established,considering the influence of different load distributions in each construction *** total strain rotating crack constitutive model was applied to reflect the cracking behaviour of concrete lining in the simulation,and the model was calibrated and verified in the *** analysis between the simulated strain distribution and the distributed optical-fibre monitoring results was carried *** deformation mode and crack distribution of the lining were *** cracking mechanism was ***,the second tunnel construction led to the loading at the top of the middle partition wall and the release of rock pressure in the first *** these load changes,the secondary lining of the first tunnel cracked on the inner side of the top of the middle partition wall owing to tension,and compression-bending failure occurred near the right arch ***,the influence of the parameters on the lining force was analysed,and a construction optimisation scheme was proposed.

关键词： Double-arch tunnel Cracking mechanism distributed optical-fibre sensing Inversion analysis Total strain rotating crack model Loadstructure method

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A novel multi-slice electromagnetic field-circuit coupling method for transient computation of long-distance gas-insulated transmission lines

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High Voltage 2024年第4期9卷 826-838页

作者： Shucan cheng Yanpu zhao Kejia Xie Bin Hu School of Electrical Engineering and Automation Wuhan UniversityWuhanChina Shandong Taikai High Voltage Switchgear Co. Ltd.TaianChina

Accurate calculation of short-circuit electromagnetic force is crucial for both mechanical strength check and the optimal design of gas-insulated transmission lines(GIL).Since the full 3D numerical simulation method is highly time-consuming,a novel lightweight 2D multi-slice electromagnetic field-circuit coupled method for computing transient electromagnetic force is proposed,where appropriate port voltage degrees of freedom(DoFs)are introduced for the solid GIL conductor *** the transient magnetic field equations are combined with the constraint equations of circuit part,including nodal voltage and loop current DoFs,a direct field-circuit coupling scheme is thus *** proposed method can simultaneously consider the effect of interphaseshunts and ground wires,as well as the skin effect and proximity *** can accurately capture the transient electromagnetic characteristics of GIL spanning from several to tens of kilometers under different short-circuit *** transient electromagnetic forces,as well as the induced voltages and currents of the enclosure,are analysed by the proposed method for both single-phase and three-phase enclosed GIL under various short-circuit *** proposed method has the advantages of high accuracy and lightweight computational cost,and thus it is also suitable for conducting important simulation tasks such as mechanical strength checks during the design optimisation phase of long-distance GIL.

关键词： transient coupling field

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Radar false alarm plots elimination based on multi-feature extraction and classification

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 83-92页

作者： cheng Yi zhao Yan Yin Peiwen School of Control Science and Engineering Tiangong UniversityTianjin 300387China Tianjin Key Laboratory of Intelligent Control of Electrical Equipment Tianjin 300387China

Caused by the environment clutter,the radar false alarm plots are *** false alarm points has always been a key issue in Radar plots *** this paper,a radar false alarm plots elimination method based on multi-feature extraction and classification is proposed to effectively eliminate false alarm ***,the density based spatial clustering of applications with noise(DBSCAN)algorithm is used to cluster the radar echo data processed by constant false-alarm rate(CFAR).The multi-features including the scale features,time domain features and transform domain features are ***,a feature evaluation method combining pearson correlation coefficient(PCC)and entropy weight method(EWM)is proposed to evaluate interrelation among features,effective feature combination sets are selected as inputs of the ***,False alarm plots classified as clutters are *** experimental results show that proposed method can eliminate about 90%false alarm plots with less target loss rate.

关键词： radar plots elimination density based spatial clustering of applications with noise multi-feature extraction classifier

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Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo Liu Shu-sen cheng Yu-qing Xue Xiao-man cheng zhao Liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

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Electronic-scale assessment of high-temperature oxidation mechanisms in a novel Fe-based alloy

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Journal of Iron and Steel Research International 2024年第4期31卷 982-997页

作者： Wei-di Luo Ting-ping Hou Xuan Liang Dong Zhang Heng-fu Lin Yu Li Tian-liang zhao cheng-yang Hu Serhii Yershov Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy.Wuhan University of Science and Technology.Wuhan 430081 HubeiChina Hubei Province Key Laboratory of Systems Science in Meallurgial Process Wuhan University of Science and Technology.Wuhan 430081.Hubei.China International Research Institute for Steel Technology Wuhan University of Science and Technology.Wuhan 430081.HubeiChina Collaborative Innovation Center for Advanced Steels w uhan University of Science and Technology.Wuhan 430081.HuleiChina

The development of alloys with high antioxidation performance is limited by the ambiguous details of the oxidation ***,based on the structures of internal oxides detected by high-resolution transmission electron microscopy,a hybrid method combining first-principles calculation,climb image nudged elastic band method and quasi-harmonic Debye model has been implemented to explain the oxidation mechanism with an emphasis on the origin of delamination and *** results showed that the delamination of oxides corresponds to the acceleration of diffusion of Cr element caused by lamellar *** reduction in the cracking occurrence at high temperature mainly results from the smaller bulk modulus of ***,the stronger chemical bonds promoted by lamellar structures also correspond to the higher crackingresistance.

关键词： Oxidation Crystal structure diffusion Cracking-First-principles calculation

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Numerical analysis of coupled sloshing and motion of a cylindrical FPSO in regular waves

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Journal of Hydrodynamics 2024年第3期36卷 457-465页

作者： Wei-wen zhao Xiao-long Yang De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Offshore Oil Engineering Co.Ltd. Tianjin300461China

In this paper,the coupled sloshing and motion characteristics of a cylindrical floating production storage offloading(CFPSO)are numerically investigated by means of computational fluid dynamics(CFD)*** simulations are performed using an in-house CFD solver naoe-FOAM-SJTU which is developed based on *** active wave generating-absorbing boundary condition(GABC)is utilized for wave generation and *** stabilized k-omega SST turbulence model are used to avoid excessive eddy viscosity near the free *** with and without partially filled liquid tanks in regular waves with different wave periods are simulated and vertical planar motions such as surge,heave and pitch response amplitude operators(RAOs)are *** due to liquid sloshing and wave loads are extracted and *** free surface motions inside liquid tanks in one wave period presented to explain the motion characteristics.

关键词： Coupled analysis liquid sloshing wave motion cylindrical floating production storage offloading(CFPSO)

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Early Cretaceous Metasomatized Lithospheric Mantle beneath the Central Jiangnan Orogen in South China:Geochemical and Sr-Nd Isotope Evidence from the Tuanshanbei Dolerite

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 602-616页

作者： WANG cheng WEI Hantao LIU Qingquan YANG zhao Guangdong Provincial Key Laboratory of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-sen UniversityGuangzhou 510275China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Development and Research Centre China Geological SurveyBeijing 100037China School of Environmental Studies China University of GeosciencesWuhan 430074China

It is well established that Cretaceous magmatism in the South China Block(SCB)is related to the Paleo-Pacific ***,the starting time and the associated deep crust-mantle processes are still *** dike swarms carry important information on the deep earth(including mantle)geodynamics and geochemical *** the Jiangnan Orogen(South China).there is no information on whether the Mesozoic magmatic activities in this region are also directly related to the Pacific subduction or *** this study,we present detailed zircon U-Pb geochronological,wholerock element and Sr-Nd isotope data for Early Cretaceous Tuanshanbei dolerite dikes,and provide new constraints on the condition of the lithospheric mantle and mantle dynamics of the SCB during that ***-ICP-MS zircon U-Pb dating suggests that this dolerite erupted in the Early Cretaceous(~145 Ma).All samples have alkaline geochemical affinities with K_(2)O+Na_(2)O=3.11-4.04 wt%,K_(2)O/Na_(2)O=0.50-0.72,and Mg^(#)=*** are enriched in LILE but depleted in HFSE with higher initial^(87)Sr/^(86)Sr ratio(0.706896-0.714743)and lower ε_(Nd)(t)(-2.61 to-1.67).They have high Nb/U,Nb/La,La/Sm and Rb/Sr,and low La/Nb,La/Ta,Ce/Pb,Ba/Rb,Tb/Yb and Gd/Yb *** geochemical signatures suggest that the fractional crystallization is obvious but crustal contamination play a negligible role during magmatic *** dolerite were most likely derived from low-degree(2%-5%)partial melting of a phlogopite-bearing mantle material consisted of~85% spinel peridotite and~15% garnet peridotite previously metasomatized by asthenospherederived fluids/melts with minor subduction-derived fluids/***-rollback generally lead to the upwelling of the hot *** upwelling of asthenosphere consuming the lithospheric mantle by thermo-mechanical-chemical *** lithospheric mantle may have partially melted due to the heating by the upwelling asthenosphere and lithospheric extension.I

关键词： Early Cretaceous mafic dike metasomatized lithospheric mantle Tuanshanbei dolerite Jiangnan Orogen South China

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