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Velocity analysis of supersonic jet flow in double-cone ignition scheme

Chinese Physics B 2024年第6期33卷 460-465页

作者：朱仲源张成龙李英骏 School of Science China University of Mining and TechnologyBeijing 100083China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing 100083China Double-cone ignition(DCI)joint team State Key Laboratory for Geomechanics and Deep Underground EngineeringChina University of Mining and TechnologyBeijing 100083China

In the double-cone ignition schemes(DCIS), the deuterium–tritium target shell is ablated and compressed by a highpower nanosecond laser in Au-cones to generate plasmas. Under the actions of spherically symmetric compression and acceleration along the Au cone, they will be ejected out of the cone mouth and collide with each other. The plasmas experience conversion from kinetic energy to internal energy at the vertex of the geometric center of two Au cones that are symmetric to each other, because of which high-density fusion plasmas are preheated. This key physical process has undergone experimental verification on the Shenguang-II upgraded facility in China. Apparently, the improvement and optimization of the velocity of plasmas in hypersonic jet flow at the cone mouth are crucial for the success of the DCIS. In the DCIR7 experiment of the Shenguang-II upgraded facility, a velocity yield of approximately 130–260 km/s was achieved for the plasmas at the cone mouth, with a result of nearly 300 km/s based on numerical simulation. In this paper, theoretical analysis is performed as regards the process, in which target shells are ablated and compressed by laser to generate highvelocity plasmas ejected through jet flow. Based on this analysis, the formula for the velocity of plasmas in supersonic jet flow at the cone mouth is proposed. This study also provides measures that are more effective for improving the kinetic energy of plasmas and optimizing energy conversion efficiency, which can serve as theoretical references for the adjustment and optimization of processes in subsequent experiments.

关键词： double-cone ignition(DCI) plasma hydrodynamics laser fusion

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Analytical model for Rayleigh-Taylor instability in conical target conduction region

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Chinese Physics B 2022年第10期31卷 450-457页

作者： zhong-yuan zhu Yun-Xing Liu Ying-Jun Li Jie Zhang School of Science China University of Mining and TechnologyBeijing 100083China Double-cone Ignition(DCI)Joint Team State Key Laboratory for Geomechanics and Deep Underground EngineeringChina University of Mining and TechnologyBeijing 100083China Double-cone Ignition(DCI)Joint Team Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China

This work builds an isobaric steady-state fluid analytical-physical model of the plasma conduction region in a conical target. The hydrodynamic instability in the double-cone ignition scheme^([21]) for inertial confinement fusion(ICF) proposed by Zhang is studied with the built model. With this idealized model, the relevant parameters, such as density, temperature,and length of the plasma in the conduction region of the conical target under long-pulse conditions are given. The solution of the proposed analytical model dovetails with the trend of the numerical simulation. The model and results in this paper are beneficial for discussing how to attenuate Rayleigh-Taylor instability in ICF processes with conical and spherical targets.

关键词： double-cone ignition Rayleigh-Taylor instability conical target conduction region

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Alternative Splicing and Expression Profile Analysis of Expressed Sequence Tags in Domestic Pig

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Genomics, Proteomics & Bioinformatics 2007年第1期5卷 25-34页

作者： Liang Zhang Lin Tao Lin Ye Ling He yuan-zhong zhu Yue-Dong zhu Yan Zhou James D. Watson Institute of Genome Sciences Zhejiang University Hangzhou 310008 China Hangzhou Genomics Institute Hangzhou 310008 China School of Life Sciences Fudan University Shanghai 200433 China. School of Life Sciences Fudan University Shanghai 200433 China

Domestic pig （Sus scrofa domestica） is one of the most important mammals to humans. Alternative splicing is a cellular mechanism in eukaryotes that greatly increases the diversity of gene products. Expression sequence tags （ESTs） have been widely used for gene discovery, expression profile analysis, and alternative splicing detection. In this study, a total of 712,905 ESTs extracted from 101 different nonnormalized EST libraries of the domestic pig were analyzed. These EST libraries cover the nervous system, digestive system, immune system, and meat production related tissues from embryo, newborn, and adult pigs, making contributions to the analysis of alternative splicing variants as well as expression profiles in various stages of tissues. A modified approach was designed to cluster and assemble large EST datasets, aiming to detect alternative splicing together with EST abundance of each splicing variant. Much efforts were made to classify alternative splicing into different types and apply different filters to each type to get more reliable results. Finally, a total of 1,223 genes with average 2.8 splicing variants were detected among 16,540 unique genes. The overview of expression profiles would change when we take alternative splicing into account.

关键词： alternative splicing expression profile EST clustering

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High cerium content(Nd-Pr-Ce)_(2)Fe_(14)B melt-spun ribbons with high coercivity

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Journal of Rare Earths 2024年第4期42卷 690-695页

作者： Yujiang zhong Junming Wang Zikai yuan Ruijin Liu Minggang zhu Zhe Liu Xin Chen Wei Li Zhaohui Guo Division of Functional Materials Central Iron and Steel Research InstituteBeijing100081China Ningbo Jinji Strong Magnetic Material Co. Ltd.Ningbo315172China Jiangxi Jiangwu Rare Metal New Material Co. Ltd.Nanchang330013China

The effects of wheel speeds on the magnetic properties and microstructures of[(Nd,Pr)_(1-x)Ce_(x)]-Fe-B meltspun ribbons were *** to melt-spun ribbons with low cerium(Ce)content(x=0.2),amorphous formation can be suppressed at high wheel speed in the ribbons with a relatively high Ce content(x=0.8),and with the increase of the wheel speed,the magnetic properties of the ribbons with high Ce content raise *** high wheel speed,the coercivity mechanism of melt-spun ribbons is mainly pinning field,and the high wheel speed introduces a large number of defects into the matrix as pinning ***,ribbons with high Ce content form a fine and uniform grain structure,so the grain boundary area enlarges,which further hinders the movement of domain *** combined effects of the above factors enable ribbons with high Ce content to have excellent magnetic properties(Hcj=0.977 T,Mr=64 m^(2) A/kg)at the wheel speed of 35 m/s.

关键词： Wheel speed Cecontent Microstructure Magnetic properties Rare earths

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The Effect of Moisture in Different Altitude Layers on the Eastward Propagation of MJO

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Journal of Meteorological Research 2024年第3期38卷 437-452页

作者： Xiaoyu zhu zhong zhong Yimin zhu Yunying LI Yijia HU Yao HA College of Meteorology and Oceanography National University of Defense TechnologyChangsha410000China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing210000China

In this study,driven by ERA5 reanalysis data,the Weather Research and Forecasting(WRF)version 4.0 was used to investigate the eastward propagation of the Madden-Julian oscillation(MJO)in the tropical atmosphere during December-February(DJF)of 2007/*** experiment with 11 cumulus parameterization schemes respectively shows that the Grell 3D scheme is one of several worse ones in describing MJO *** addition,still by use of the Grell 3D scheme,four nudging assimilation experiments for water vapor in all model vertical layers(Ndg_all),lower layers(Ndg_low),middle layers(Ndg_mid),and upper layers(Ndg_upp)were *** is found that when the water vapor in the model approaches to the observed value,the model performance for MJO activities is improved *** the four nudging simulations,Ndg_all certainly performs *** Ndg_mid is important for the MJO-filtered profiles related to moisture,Ndg_low and Ndg_upp exhibit superiority to Ndg_mid in simulating MJO eastward ***_low has advantages when MJO features are represented by zonal wind at 850 hPa and precipitation because the lower-level MJO-filtered moisture is conducive to the existence of lower-level condensational heating to the east of the MJO convective ***_upp performs better when describing the MJO eastward propagation features by outgoing longwave radiation(OLR)since it can capture the moisture and cloud top temperature of deep convection associated with MJO,as well as front Walker *** results suggest that the lower-level moisture is more important in regulating the MJO eastward propagation,and the observed maximum MJO-filtered moisture in the middle troposphere might be a phenomenon accompanying the MJO deep convection,but not a factor controlling its eastward propagation.

关键词： Madden-Julian oscillation(MJO) nudging technique Weather Research and Forecasting(WRF)model vertical moisture structure

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Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 139-146页

作者： Guan-Wen yuan Lei Lei yuan-zhu Wang Bo Wang Yi-Ying Wang Chao Chen Zhao-Qiang Shen Yi-Fu Cai Yi-zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope(JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes(PBHs)with a mass of~1000M_(⊙).These PBHs act as seeds for early galaxy formation with masses of~10^(8)-10^(10)M_(⊙)at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the M_(c)~750M_(⊙)is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

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GNAS mutations suppress cell invasion by activating MEG3 in growth hormone–secreting pituitary adenoma

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Oncology Research 2024年第6期32卷 1079-1091页

作者： CHAO TANG CHUNYU zhong JUNHAO zhu FENG yuan JIN YANG YONG XU CHIyuan MA Department of Neurosurgery Affiliated Jinling HospitalMedical School of Nanjing UniversityNanjing210002China Department of Neurosurgery Children’s Hospital of Nanjing Medical UniversityNanjing210019China Affiliated Eye Hospital Nanjing Medical UniversityNanjing210029China Department of Neurosurgery Jinling HospitalSouthern Medical UniversityNanjing210002China Department of Neurosurgery Jinling HospitalNanjing Medical UniversityNanjing210002China

Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of smaller and less invasive ***,the role of GNAS mutations in the invasiveness of GHPAs is *** mutations were detected in GHPAs using a standard polymerase chain reaction(PCR)sequencing *** expression of mutation-associated maternally expressed gene 3(MEG3)was evaluated with ***3 was manipulated in GH3 cells using a lentiviral expression *** invasion ability was measured using a Transwell assay,and epithelial–mesenchymal transition(EMT)-associated proteins were quantified by immunofluorescence and western ***,a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and *** invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type ***,the invasiveness of mutant GNASexpressing GH3 cells ***3 is uniquely expressed at high levels in GHPAs harboring mutated ***,MEG3 upregulation inhibited tumor cell invasion,and conversely,MEG3 downregulation increased tumor cell ***,GNAS mutations inhibit EMT in ***3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/β-catenin signaling pathway,which was further validated in *** data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/β-catenin signaling pathway.

关键词： GHPAs GNAS mutation MEG3 β-catenin EMT

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Gradient microstructure and superior strength-ductility synergy of AZ61 magnesium alloy bars processed by radial forging with different deformation temperatures

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Journal of Materials Science & Technology 2024年第3期170卷 65-77页

作者： Jingfeng Zou Lifeng Ma Yanchun zhu Ling Qin yuan yuan School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Heavy Machinery Engineering Research Center of the Ministry Education Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Engineering University of HullCottingham RdHull HU67RXUK National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China

Gradient microstructure modification is a cost-efficient strategy for high strength without compromising ductility,which is urgently needed in the fundamental science of engineering *** this study,heterogeneous structures of AZ61 alloy bars with anisotropic gradients(with different grain size distributions from the surface to the center)were observed to exhibit strong strength-ductility synergies under different deformation tem *** results reveal that the grain refinement process under mediumlow temperature deformation conditions(≤350℃)consists of four transition stages along the radial direction,i.e.,twin activations and deformation band formations,dislocation cells and pile-ups,ultrafine sub-grains,and randomly orientated quasi-micron *** deformation temperatures have a great influence on twin activations and deformation band formations,and the high temperature can easily provoke the initiation of non-basal *** deformation bands were determined as a primary nucleation site due to their highly unstable dislocation hindrance *** in combination with the Radial forging(RF)deformation process,the differences of dynamic precipitates can be attributed to microstructural difference and solubility limit of Al at different tem *** summarizing the tensile test results,the sample forged at 350℃exhibited the best strength-ductility synergy,exhibiting the highest elongation(EL)of 23.2%with a 251 MPa yield strength(YS)and 394 MPa ultimate tensile strength(UTS)in center region,and combined with the highest strength value of 256 MPa YS and 420 MPa UTS in the center region,while the EL was slightly degraded to 19.8%.

关键词： Gradient microstructure Radial forging Strength-ductility synergy Magnesium alloy Strengthening mechanism

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A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 255-273页

作者： zhong Qu Guoqing Mu Bin yuan School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing400065China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this ***,as the performance of crack detection in cement pavement improves,the depth and width of the network structure are significantly increased,which necessitates more computing power and storage *** limitation hampers the practical implementation of crack detection models on various platforms,particularly portable devices like small mobile *** solve these problems,we propose a dual-encoder-based network architecture that focuses on extracting more comprehensive fracture feature information and combines cross-fusion modules and coordinated attention mechanisms formore efficient feature ***,we use small channel convolution to construct shallow feature extractionmodule(SFEM)to extract low-level feature information of cracks in cement pavement images,in order to obtainmore information about cracks in the shallowfeatures of *** addition,we construct large kernel atrous convolution(LKAC)to enhance crack information,which incorporates coordination attention mechanism for non-crack information filtering,and large kernel atrous convolution with different cores,using different receptive fields to extract more detailed edge and context ***,the three-stage feature map outputs from the shallow feature extraction module is cross-fused with the two-stage feature map outputs from the large kernel atrous convolution module,and the shallow feature and detailed edge feature are fully fused to obtain the final crack prediction *** evaluate our method on three public crack datasets:DeepCrack,CFD,and *** results on theDeepCrack dataset demonstrate the effectiveness of our proposed method compared to state-of-the-art crack detection methods,which achieves Precision(P)87.2%,Recall(R)87.7%,and F-score(F1)87.4%.Thanks to our lightweight cr

关键词： Shallow feature extraction module large kernel atrous convolution dual encoder lightweight network crack detection

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Spatial-and spin-resolution ARPES and magnetism beamline at SSRF

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Nuclear Science and Techniques 2024年第8期35卷 23-37页

作者： Fang‑yuan zhu Jie‑Feng Cao Xiang‑Yu Meng Jun‑Qin Li Rui Yu Ya‑Mei Wang Shan Qiao Bo Zhao Ming‑zhu Zhang zhong‑Kai Liu Mei‑Xiao Wang Yong Wang Ren‑zhong Tai Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China ShanghaiTech Laboratory for Topological Physics School of Physical Science and TechnologyShanghai Tech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China

The BL07U beamline is a new extreme ultraviolet and soft X-ray beamline housed in the Shanghai Synchrotron Radiation Facility. Beamlines are used in nano-resolved angle-resolved photoemission spectroscopy(nano-ARPES), spin-resolved angle-resolved photoemission spectroscopy(spin-ARPES), X-ray magnetic circular dichroism spectroscopy, and X-ray magnetic linear dichroism spectroscopy for certain scientific research. The BL07U beamline, which is based on a pair of elliptical polarized undulators and a variable-included-angle plane-grating monochromator, delivers circularly or linear polarized X-rays within the energy range of 50–2000 eV. The beamline features two branches: One dedicated to nano-ARPES,which has a minimum spot size of only ~ 200 nm, and another branch comprising spin-ARPES, a vector magnetic field, and superconductive magnetic end-station.

关键词： Soft X-ray beamline Nano-ARPES Spin-ARPES XMCD/XMLD

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