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Chinese Annals of Mathematics,Series B 2024年第4期45卷 537-554页

作者： Shuangrong LI Wancheng sheng Department of Mathematics Shanghai UniversityShanghai 200444China Department of Mathematics Zhejiang University of Science and TechnologyHangzhou 310023China Corresponding author.Department of Mathematics Newtouch Center for Mathematics of Shanghai UniversityShanghai UniversityShanghai 200444China

In this paper,the authors study the centered waves for the two-dimensional(2D for short)pseudo-steady supersonic flow with van der Waals gas satisfied Maxwell's law around a sharp *** view of the initial value of the specific volume and the properties of van der Waals gas,the centered waves at the sharp corner are constructed by *** is shown that the supersonic incoming flow turns the sharp corner by a centered simple wave or a centered simple wave with right-contact discontinuity or a composite wave(jump-fan,fan-jump or fan-jump-fan),or a combination of waves and constant ***,the critical angle of the sharp corner corresponding to the appearance of the vacuum phenomenon is obtained.

关键词： Two-dimensional Euler equations Van der Waals gas Centered simple wave Composite wave

Ground-layer Adaptive Optics for the 2.5 m Wide-field and High-resolution Solar Telescope

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Research in Astronomy and Astrophysics 2024年第3期24卷 224-236页

作者： Ying Yang Lan-Qiang Zhang Nan-Fei Yan Jin-sheng Yang Zhen Li Teng-Fei Song Xue-Jun Rao chang-Hui Rao Key Laboratory on Adaptive Optics Chinese Academy of SciencesChengdu 610209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China School of Electronic Electrical and Communication Engineering of the University of Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern A&A Ministry of EducationNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650216.China

The 2.5 m wide-field and high-resolution solar telescope(WeHoST)is currently under developing for solar *** aims to achieve high-resolution observations over a super-wide field of view(FOV)of5′×5′,and a desired resolution of 0.3″.To meet the scientific requirements of WeHoST,the ground-layer adaptive optics(GLAO)with a specially designed wave front sensing system is as the primary *** introduce the GLAO configuration,particularly the wave front sensing *** analytic method,we simulate the performance of both classical AO and GLAO systems,optimize the wave front sensing system,and evaluate GLAO performance in terms of PSF uniformity and correction improvement across whole *** results indicate that,the classical AO will achieve diffraction-limited resolution;the suggested GLAO configuration will uniformly improve the seeing across the full 5′×5′FOV,reducing the FWHM across the axis FOV to less than0.3″(λ≥705 nm,r0≥11 cm),which is more than two times *** specially designed wave front sensor schedule offers new potential for WeHoST’s GLAO,particularly the multi-FOV GLAO and the flexibility to select the detected *** capabilities will significantly enhance the scientific output of the telescope.

关键词： instrumentation adaptive optics-instrumentation detectors-instrumentation high angular resolution-methods numerical-telescopes-Sun activity

Near-infrared organic lasers with ultra-broad emission bands by simultaneously harnessing four-level and six-level systems

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Chinese Chemical Letters 2024年第8期35卷 288-293页

作者： Lei Wang Jun-Jie Wu chang-Cun Yan Wan-Ying Yang Zong-Lu Che Xin-Yu Xia Xue-Dong Wang Liang-sheng Liao Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices Institute of Functional Nano&Soft Materials(FUNSOM)Soochow UniversitySuzhou 215123China Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyMacao SAR 999078China

Organic lasers with broad emission bands in near-infrared(NIR)region are crucial for their applications in laser communication,night-vision as well as bioimaging owing to the abundance of selectable lasing ***,for most organic gain materials,gain regions are limited in a small wavelength range because of the fixed energy level ***,we design a strategy to realize NIR organic lasers with broad emission bands based on tunable energy level systems induced by cascaded excited-state intramolecular proton transfer(ESIPT).A novel gain material named DHNN was developed,which can undergo a cascaded double-ESIPT process supporting four-level and six-level systems *** doping DHNN into polystyrene microspheres,NIR lasers with tunable emission bands can be achieved based on the careful modulation of ***,organic lasers with an ultra-broad emission band ranging from 700 nm to 900 nm was successfully achieved by harnessing four-level and six-level systems simultaneously.

关键词： Excited-state intramolecular proton transfer Organic solid-state laser Wide gain interval Near-infrared emission Molecular design

Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-cheng Gu Zhao-Jing Han Ze-Yu Chen Zhao-Xuan Li sheng-Bao Xia Zheng-Ning Li Hua Jin Wei-Wei Xu Xing-Jun Liu Shenzhen Research Institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods

Streamlined whole-genome genotyping through NGS-enhanced thermal asymmetric interlaced(TAIL)-PCR

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Plant Communications 2024年第9期5卷 25-37页

作者： sheng Zhao Yue Wang Zhenghang Zhu Peng Chen Wuge Liu Chongrong Wang Hong Lu Yong Xiang Yuwen Liu Qian Qian Yuxiao chang Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China 2 Guangdong Provincial Key Laboratory of New Technology in Rice Breeding Rice Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640China

Whole-genome genotyping(WGG)stands as a pivotal element in genomic-assisted plant ***theless,sequencing-based approaches for WGG continue to be costly,primarily owing to the high expenses associated with library preparation and the laborious *** prior development of foreground and background integrated genotyping by sequencing(FBI-seq),we discovered that any sequence-specific primer(SP)inherently possesses the capability to amplify a massive array of stable and reproducible non-specific PCR products across the ***,we further improved FBI-seq by replacing the adapter ligated by Tn5 transposase with an arbitrary degenerate(AD)*** protocol for the enhanced FBI-seq unexpectedly mirrors a simplified thermal asymmetric interlaced(TAIL)-PCR,a technique that is widely used for isolation of flanking ***,the improved TAIL-PCR maximizes the primer-template mismatched annealing capabilities of both SP and AD *** addition,leveraging of next-generation sequencing enhances the ability of this technique to assay tens of thousands of genome-wide loci for any *** cost-effective,user-friendly,and powerful WGG tool,which we have named TAIL-PCR by sequencing(TAIL-peq),holds great potential for widespread application in breeding programs,thereby facilitating genome-assisted crop improvement.

关键词： whole-genome genotyping primer-template mismatched annealing specific primer arbitrary degenerate primer molecular breeding

Deep carbon recycling viewed from global plate tectonics

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National Science Review 2024年第06期11卷 37-55页

作者： Maoliang Zhang sheng Xu Yuji Sano School of Earth System Science Tianjin University Marine Core Research Institute Kochi University Atmosphere and Ocean Research Institute The University of Tokyo

Plate tectonics plays an essential role in the redistribution of life-essential volatile elements between Earth's interior and surface, whereby our planet has been well tuned to maintain enduring habitability over much of its history. Here we present an overview of deep carbon recycling in the regime of modern plate tectonics,with a special focus on convergent plate margins for assessing global carbon mass balance. The up-to-date flux compilation implies an approximate balance between deep carbon outflux and subduction carbon influx within uncertainty but remarkably limited return of carbon to convecting mantle. If correct, carbon would gradually accumulate in the lithosphere over time by（i） massive subsurface carbon storage occurring primarily in continental lithosphere from convergent margins to continental interior and（ii） persistent surface carbon sinks to seafloors sustained by high-flux deep CO2emissions to the atmosphere. Further assessment of global carbon mass balance requires updates on fluxes of subduction-driven carbon recycling paths and reduction in uncertainty of deep carbon outflux. From a global plate tectonics point of view, we particularly emphasize that continental reworking is an important mechanism for remobilizing geologically sequestered carbon in continental crust and sub-continental lithospheric mantle. In light of recent advances,future research is suggested to focus on a better understanding of the reservoirs, fluxes, mechanisms, and climatic effects of deep carbon recycling following an integrated methodology of observation, experiment,and numerical modeling, with the aim of decoding the self-regulating Earth system and its habitability from the deep carbon recycling perspective.

关键词： deep carbon recycling convergent plate margins subduction continental reworking global carbon mass balance

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过渡期生长激素缺乏症的管理

中国当代儿科杂志 2024年第3期26卷 224-229页

作者：成胜权空军军医大学西京医院儿科陕西西安710032

随着对生长激素缺乏症认识的不断深入,临床逐渐重视过渡期生长激素缺乏症(transition growth hormone deficiency,TGHD)的管理。TGHD诊治不足是主要的临床痛点,为规范TGHD诊治,国内外已发布了相关指南/共识。该文结合指南/共识和现有临... 详细信息

随着对生长激素缺乏症认识的不断深入,临床逐渐重视过渡期生长激素缺乏症(transition growth hormone deficiency,TGHD)的管理。TGHD诊治不足是主要的临床痛点,为规范TGHD诊治,国内外已发布了相关指南/共识。该文结合指南/共识和现有临床研究,总结了TGHD的评估、诊断、治疗和临床挑战,以期优化和进一步改善TGHD临床诊治和管理。

关键词：生长激素缺乏症过渡期疾病管理重组人生长激素

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

作者： Gu-jun Chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

Incorporating contextual evidence to improve implicit discourse relation recognition in Chinese

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Frontiers of Computer Science 2024年第3期18卷 91-104页

作者： sheng XU Peifeng LI Qiaoming ZHU School of Computer Science and Technology Soochow UniversitySuzhou 215000China

The discourse analysis task,which focuses on understanding the semantics of long text spans,has received increasing attention in recent *** a critical component of discourse analysis,discourse relation recognition aims to identify the rhetorical relations between adjacent discourse units(e.g.,clauses,sentences,and sentence groups),called arguments,in a *** works focused on capturing the semantic interactions between arguments to recognize their discourse relations,ignoring important textual information in the surrounding ***,in many cases,more than capturing semantic interactions from the texts of the two arguments are needed to identify their rhetorical relations,requiring mining more contextual *** this paper,we propose a method to convert the RST-style discourse trees in the training set into dependency-based trees and train a contextual evidence selector on these transformed *** this way,the selector can learn the ability to automatically pick critical textual information from the context(i.e.,as evidence)for arguments to assist in discriminating their *** we encode the arguments concatenated with corresponding evidence to obtain the enhanced argument ***,we combine original and enhanced argument representations to recognize their *** addition,we introduce auxiliary tasks to guide the training of the evidence selector to strengthen its selection *** experimental results on the Chinese CDTB dataset show that our method outperforms several state-of-the-art baselines in both micro and macro F1 scores.

关键词： discourse parsing discourse relation recognition contextual evidence selection

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth