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Journal of Iron and Steel Research(International) 2022年第5期29卷 859-865页

作者： wen-hao gong De-hong Lu Guang-yu He Wei Ma Qing-hua Yan Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China

The effect of the volume fraction of 3D-metal matrix composites(MMC)framework on the compressive properties of 3D interpenetrating hierarchical ZrO_(2)-toughened Al_(2)O_(3)particle(ZTAp)/40Cr steel composites was *** results showed that the compressive properties of the material tended to decrease as the volume fraction of 3D-MMC framework *** composite with 35 vol.%3D-MMC had a yield strength of 1455.2 MPa and compressive strength of 1612.8 MPa,which occurred at a strain value of 5.6%.Compared to the homogeneously dispersed composite material,the composite with 35 vol.%3D-MMC had a 144.7%higher yield strength,which occurred at a 20%higher *** analysis of the cracks inside the material revealed that the crack was hindered and deflected by the matrix during propagation,which lengthened the crack propagation path and consumed more energy,thus leading to *** results indicated that 3D interpenetrating hierarchical structure had a strengthening and toughening effect on ZTAp/40Cr composites.

关键词： Architectured composite Metal matrix composite ZrO_(2)-toughened Al_(2)O_(3) Compressive property Hierarchical composite

Nonexistence of quantum black and white hole horizons in an improved dynamic approach

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 56-73页

作者： wen-Cong Gan Xiao-Mei Kuang Zhen-hao Yang Yungui gong Anzhong Wang Bin Wang College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China GCAP-CASPER Physics DepartmentBaylor UniversityWaco 76798-7316USA Institute for Theoretical Physics&Cosmology Zhejiang University of TechnologyHangzhou 310023China United Center for Gravitational Wave Physics(UCGWP) Zhejiang University of TechnologyHangzhou 310023China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Department of Physics School of Physical Science and TechnologyNingbo UniversityNingbo 315211China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

In this paper,we study the quantum geometric effects near the locations where classical black hole horizons used to appear in Einstein's classical theory,within the framework of an improved dynamic approach,in which the internal region of a black hole is modeled by the Kantowski-Sachs(KS)spacetime and the two polymerization parameters are functions of the phase space *** detailed analysis shows that the effects are so strong that black and white hole horizons of the effective quantum theory do not exist at all and instead are replaced by transition surfaces,across which the metric coefficients and their inverses are smooth and remain finite,as are the corresponding curvatures,including the Kretschmann *** surfaces always separate trapped regions from anti-trapped *** number of such surfaces is infinite,so the corresponding KS spacetimes become geodesically complete,and no black and white hole-like structures exist in this scheme.

关键词： canonical quantization loop quantum gravity quantum aspects of black holes

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Isotopic insights on quantitative assessments of interaction of eco-hydrological processes in multi-scale karst watersheds

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International Soil and Water Conservation Research 2024年第1期12卷 156-170页

作者： Zhuo hao Yang Gao Qingwen Zhang wen wen Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Humanities and Social Sciences Beijing Institute of TechnologyBeijing100081China

The dynamics of hydrological processes and the storage mechanisms of karst water resources are the most important issues in karst *** impact of environmental changes on water quantity,and the evaluation and quantification of eco-hydrological processes remain poorly *** this study,high-frequency continuous monitoring in multi-scale karst watersheds in Southwest China combined the approaches of water isotopes and the hybrid single-particle lagrangian integrated trajectory(HYSPLIT)model to identify the recharge mechanisms between atmospheric vapor,rainfall,surface water,and groundwater,and to reveal the interaction of eco-hydrological *** dominant moisture sources in Puding(PD)County were the Indian Ocean(43-69%)and local moisture(24-33%).Theδ^(18)O and deuterium excess(d-excess)values showed a positive correlation indicating that secondary or sub-cloud evaporation was prominent in the wet *** water line-conditioned excess(lc-excess)indicated that karst water interacted with recent precipitation,groundwater,and evaporation across *** to its specific hydrogeological structure,surface water and rainwater have a higher contribution rate to groundwater *** Chenqi stream replenished the Houzhai River mainly in the form of groundwater,with percentages ranging from 38.1 to 93.5%in the wet season,and 47.8-80.1%in the dry *** the Houzhai outlet,surface water and groundwater interconverted frequently with a percentage of 45.6-49.1%.We believe this is the first systematic study to quantify the supply relationship between water vapor transport,rainfall,surface water and groundwater in the Chinese karst zone,making a significant move forward in the field of karst hydrological processes and improving the efficiency of water resource evaluation and management.

关键词： Stable isotope Moisture sources Water cycle Karst watersheds

Weakly Approximate Diagonalization of Homomorphisms into Finite von Neumann Algebras

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2187-2194页

作者： wen Hua QIAN Jun hao SHEN wen Ming WU School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematics and Statistics University of New HampshireDurhamNH 03824USA

Let A be a unital C^(∗)-algebra and B a unital C^(∗)-algebra with a faithful traceτ.Let n be a positive *** give the definition of weakly approximate diagonalization(with respect toτ)of a unital homomorphismφ:A→Mn(B).We give an equivalent characterization of McDuff II1 *** show that,if A is a unital nuclear C^(∗)-algebra and B is a type II1 factor with faithful traceτ,then every unital^(∗)-homomorphismφ:A→Mn(B)is weakly approximately *** B is a unital simple infinite dimensional separable nuclear C^(∗)-algebra,then any finitely many elements in Mn(B)can be simultaneously weakly approximately diagonalized while the elements in the diagonals can be required to be the same.

关键词： Weakly approximately diagonalizable McDuff factors nuclear hyperfinite

Magmatic-tectonic response of the South China Craton to the Paleo-Pacific subduction during the Triassic:a new viewpoint based on Well NK-1

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Journal of Oceanology and Limnology 2024年第1期42卷 58-89页

作者： Chan WANG hao LIU Gang LI Zhen SUN Tingting gong Li MIAO Xiaowei ZHU Yunying ZHANG Weihai XU wen YAN Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory of Tectonic Controlled Mineralization and Oil Reservoir of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China College of Earth Science Chengdu University of TechnologyChengdu 610059China University of Chinese Academy of Sciences Beijing 100049China

The Nansha Block(NB)is one of the blocks separated from the southern margin of the South China Craton(SCC)by the western Pacific subduction,which contains rich information of geodynamic and tectonic *** reveal the essence of western Paleo-Pacific subduction during the Triassic period,Well NK-1 in this block was selected for petrographic study,and published research data from other cooperative teams were compared.A double-cycle pattern of basic to neutral magmatic volcanism was established,and 36 lithological rhythmic layers and representative cryptoexplosive breccia facies and welded tuff bands were *** with a reanalysis of published geochronological data,geochemical elements,and isotope geochemistry,we found that the rock assemblages could be divided into an intermediate-acid dacite(DA)series(SiO_(2)>65%)and basaltic(BA)series(Co<40μg/g),which was formed during the early Late Triassic((218.6±3.2)–(217.9±3.5)Ma).BA exhibits obvious calc-alkaline island-arc magmatic properties:(^(87)Sr/^(86)Sr)_i ratio ranging 0.70377–0.71118(average:0.70645),^(147)Sm/^(144)Nd ratio ranging 0.119–0.193(average:0.168),and chondrite-normalized rare earth element(REE)curves being flat,while DA exhibits remarkable characteristics of subducted island-arc andesitic magma:(^(87)Sr/^(86)Sr)_i ratio(0.70939–0.71129;average:0.71035),εNd(t)value(-6.2–-4.8;average:-5.6)andε_(Hf)(t)value(-2.9–-1.7,average:-2.2)show obvious crust-mantle mixing *** and DA reveal typical characteristics of island-arc magma systems and typeⅡenriched mantle(EM-Ⅱ)*** magma was likely resulted from the process whereby the continental crust frontal accretionary wedge was driven by the Paleo-Pacific slab subduction into the deep and began to melt,resulting in a large amount of melt(fluid)joined the asthenosphere on the side of the continental *** contrast,DA magma was likely resulted from the process whereby the plate front was forced to bend with increasing subducti

关键词： Paleo-Pacific tectonic domain tectonic evolution rift volcanic rock Nansha Block South China Craton

Observation of gapless corner modes of photonic crystal slabs in synthetic translation dimensions

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Photonics Research 2024年第3期12卷 444-455页

作者： wen-JIN ZHANG hao-CHANG MO wen-JIE CHEN XIAO-DONG CHEN JIAN-wen DONG School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China

Second-order topological photonic crystals support localized corner modes that deviate from the conventional bulk-edge ***,the frequency shift of corner modes spanning the photonic band gap has not been experimentally ***,we observe the gapless corner modes of photonic crystal slabs within a parameter space by considering translation as an additional synthetic *** corner modes,protected by topological pumping in synthetic translation dimensions,are found to exist independently of the specific corner *** gapless corner modes are experimentally imaged via the near-field scanning measurement and validated numerically by full-wave *** propose a topological rainbow with gradient translation,demonstrating the ability to extract and separate specific frequency components of light into different spatial *** work contributes to the advancement of topological photonics and provides valuable insights into the exploration of gapless corner modes in synthetic dimensions.

关键词： translation dimensions corner

On the improved dynamics approach in loop quantum black holes

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Communications in Theoretical Physics 2024年第3期76卷 138-143页

作者： Hongchao Zhang wen-Cong Gan Yungui gong Anzhong Wang Institute for Theoretical Physics&Cosmology Zhejiang University of TechnologyHangzhou310023China United Center for Gravitational Wave Physics(UCGWP) Zhejiang University of TechnologyHangzhou310023China College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China GCAP-CASPER Physics DepartmentBaylor UniversityWacoTX 76798-7316United States of America School of Physics Huazhong University of Science and TechnologyWuhanHubei 430074China Department of Physics School of Physical Science and TechnologyNingbo UniversityNingboZhejiang 315211China

In this paper,we consider the B?hmer–Vandersloot(BV)model of loop quantum black holes obtained from the improved dynamics *** adopt the Saini–Singh gauge,in which it was found analytically that the BV spacetime is geodesically *** show that black/white hole horizons do not exist in this geodesically complete ***,there exists only an infinite number of transition surfaces,which always separate trapped regions from anti-trapped *** on the improved dynamics approach adopted in other models of loop quantum black holes are also given.

关键词： loop quantum gravity black hole dynamics approach

Molecular dynamics study of hydrogen-induced cracking behavior of ferrite–pearlite gas transmission pipeline steel

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Journal of Iron and Steel Research(International) 2024年第2期31卷 488-500页

作者： Tao-long Xu Si-han Guo gong-zhen He hao-yu Han Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Sichuan East Gas Transmission Sales Center of Sinopec Natural Gas Branch Wuhan430074HubeiChina

Hydrogen embrittlement of pipelines depends on the hydrogen-induced cracking behavior of the pipeline steel *** on molecular dynamics analysis,the ferrite–cementite(α-Fe/Fe3C)lamellar atomic structure with the Bagaryatskii orientation relationship was established,and stepwise relaxation of the conjugate gradient energy minimization and constant-temperature and constant-pressure relaxation were performed under NPT(the isothermal–isobaric)*** mechanical property curves of theα-Fe/Fe3C models were obtained under different cementite terminal plane structures,and the evolution of the atomic structure was analyzed in *** addition,the influence of different hydrogen concentrations,different temperatures,different strain rates,changes in voids,and different micro-degrees of freedom on the deformation and failure mechanism of the model was investigated,aiming to provide a reliable way to explore the micro-mechanism of macro-cracking behavior of pipeline steel.

关键词： Ferrite-cementite lamellar structure Pipeline steel Failure mechanism Crack propagation Molecular dynamics

DLF-YOLOF:an improved YOLOF-based surface defect detection for steel plate

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Journal of Iron and Steel Research(International) 2024年第2期31卷 442-451页

作者： Guang-hu Liu Mao-xiang Chu Rong-fen gong Ze-hao Zheng School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051LiaoningChina

Surface defects can affect the quality of steel *** methods based on computer vision are currently applied to surface defect detection of steel ***,their real-time performance and object detection of small defect are still *** improved object detection network based on You Only Look One-level Feature(YOLOF)is proposed to show excellent performance in surface defect detection of steel plate,called ***,the anchor-free detector is used to reduce the network ***,deformable convolution network and local spatial attention module are introduced into the feature extraction network to increase the contextual information in the feature ***,the soft non-maximum suppression is used to improve detection accuracy ***,data augmentation is performed for small defect objects during training to improve detection *** show the average precision and average precision for small objects are 42.7%and 33.5%at a detection speed of 62 frames per second on a single GPU,*** shows that DLF-YOLOF has excellent performance to meet the needs of industrial real-time detection.

关键词： Steel surface defects detection YOLOF Anchor-free detector Small object detection Real-time detection

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research(International) 2024年第3期31卷 647-659页

作者： Shun-hu Zhang Yi Zhang wen-hao Tian Yan Li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： Yield criterion Plastic deformation Rolling force Velocity field Analytical solution