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Theory and test of underground explosions:Coupling rule between cratering and ground shock

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Underground Space 2024年第4期17卷 146-160页

作者： Wei Guo Jie Li Benjun Shi Tianhan xu Xiaohui xu Gan Li Jie Shi State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact Army Engineering University of PLANanjing 210007China

Calculating the parameters of the ground shock induced by an underground explosion is a complex energy coupling *** is difficult to establish a unified ground shock coupling law from limited test *** paper summarizes the research results obtained at home and abroad and systematically analyzes the coupling mechanism of craters formed by an underground explosion and the ground *** differences between the concepts of"closed-explosion critical depth"and"equivalent closed-explosion critical depth"are clearly *** spreading of the ground shock energy is attributed to the explosive expansion of the air cavity,revealing a linear relationship between the volume of the cavity region(or the volume of the crack region)and the ground shock energy associated with the underground *** proportionality factor is related to the mechanical properties of the medium and is independent of the magnitude of the explosion *** on this,a theoretical calculation formula and conversion method for the ground shock coupling coefficient were *** tests were conducted in clay and Plexiglass under varying burial *** test results were consistent with the theoretically calculated *** study provides a theoretical basis for the design of explosion-resistant structures in underground engineering.

关键词： Underground explosion Ground shock coupling Coupling coefficient Equivalent closed explosion Experimental study

Phonon-blockade-based multiple-photon bundle emission in a quadratically coupled optomechanical system

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Frontiers of physics 2024年第3期19卷 207-215页

作者： Ye-Jun xu Hong Xie Interdisciplinary Research Center of Quantum and Photoelectric Information Chizhou UniversityChizhou 247000China Department of Mathematics and Physics Fujian Jiangxia UniversityFuzhou 350108China

We propose a scheme to realize antibunched multiple-photon bundles based on phonon blockade in a quadratically coupled optomechanical *** adjusting the detunings to match the conditions of phonon blockade in the photon sidebands,we establish super-Rabi oscillation between zero-photon state and multiple-photon states with adjustable super-Rabi frequencies under appropriate single-phonon resonant *** the system dissipation into account,we numerically calculate the standard and generalized second-order functions of the cavity mode as well as the quantum trajectories of the state populations with Monte Carlo simulation to confirm that the emitted photons form antibunched multiple-photon ***,the desirable n-photon states are reconstructed after a direct phonon emission based on phonon blockade,and thus the single-phonon emission heralds the cascade emission of n-photon *** proposal shows that the optomechanical system can simultaneously behave as antibunched multiple-photon emitter and single-phonon *** a nonclassical source could have potential applications in quantum information science.

关键词： multiple-photon bundle emission phonon blockade optomechanical system

Scattering for the Radial Schrodinger Equation with Combined Power-type and Choquard-type Nonlinearities

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1029-1041页

作者： Ying WANG Cheng Bin xu The Graduate School of China Academy of Engineering Physics Beijing 100088P.R.China School of Mathematics and Statistics Qinghai Normal UniversityXining 810008P.R.China

In this paper,we show the scattering of the radial solution for the nonlinear Schrodinger equation with combined power-type and Choquard-type nonlinearities iut+△u=λ1|u|p1-1u+λ2(Iα*|u|^(p2))|u|p^(2-2)*** the energy space H^(1)(R^(N))forλ_(1)λ_(2)=-*** establish a scattering criterion for radial solution together with Morawetz estimate which implies the scattering *** show that the defocusing perturbation terms does not determine the scattering solution in energy space.

关键词： Schrodinger equation Choquard-type Scattering theory

Boundary Behaviors for a Continuous-state Nonlinear Neveu’s Branching Process

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2005-2016页

作者： Lin Yu BAI xu YANG School of Mathematics and Information Science North Minzu UniversityYinchuan 750021P.R.China

By generalizing a criterion of Mufa Chen for Markov jump processes,we establish the necessary and sufficient conditions for the extinction,explosion and coming down from infinity of a continuous-state nonlinear Neveu... 详细信息

关键词： Continuous-state branching process nonlinear branching Neveu’s branching extinction explosion coming down from infinity

(Lu_(1/7)Yb_(1/7)Sc_(1/7)Er_(1/7)Y_(1/7)Ho_(1/7)Dy_(1/7))_(2)Si_(2)O_(7)high entropy rare-earth disilicate with low thermal conductivity and excellent resistance to CMAS corrosion

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Journal of Advanced Ceramics 2024年第5期13卷 549-560页

作者： xu Wang Mingyu Meng Feihan xu Ling Liu Lihong Gao Shizhen Zhu Zhuang Ma School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing 100081China Tangshan Research Institute Beijing Institute of TechnologyTangshan 063000China

Low thermal conductivity,compatible thermal expansion coefficient,and good calcium–magnesium–aluminosilicate(CMAS)corrosion resistance are critical requirements for environmental barrier coatings used on silicon-based ***2Si2O7(RE=rare earth)has been widely recognized as one of the most promising candidates for environmental barrier coatings due to its good water vapor corrosion ***,the relatively high thermal conductivity and poor resistance to CMAS corrosion have limited its practical *** by the high entropy effect,in this work,a novel rare earth disilicate(Lu_(_(1/7))Yb_(_(1/7))Sc_(_(1/7))Er_(_(1/7))Y_(_(1/7))Ho_(_(1/7))Dy_(_(1/7)))2Si2O7((7RE_(_(1/7)))2Si2O7)has been designed and synthesized by a solid reaction process.(7RE_(_(1/7)))2Si2O7 showed a low thermal conductivity of 1.81 W·m^(−1)·K^(−1)at 1273 ***,the thermal expansion coefficient of(7RE_(_(1/7)))_(2)Si_(2)O_(7)(4.07×10^(−6)℃^(−1)from room temperature(RT)to 1400℃)is close to that of the SiC-based ceramic matrix composites(SiC-CMCs)((4.5–5.5)×10^(−6)℃^(−1)).Additionally,(7RE_(_(1/7)))2Si2O7 exhibited excellent resistance to CMAS *** exposed to CMAS at 1300℃for 48 h,the reaction layer thickness was 22μ*** improved performance of(7RE_(_(1/7)))2Si2O7 highlights its potential as a promising candidate for thermal/environmental barrier coatings.

关键词： high entropy disilicate (Lu_(1/7)Yb_(1/7)Sc_(1/7)Er_(1/7)Y_(1/7)Ho_(1/7)Dy_(1/7))_(2)Si_(2)O_(7)((7RE_(1/7))_(2)Si_(2)O_(7)) high-temperature thermal properties calcium-magnesium-aluminosilicate(CMAS)corrosion

Strong hetero-interface interaction in 2D/2D WSe_(2)/ZnIn_(2)S_(4) heterostructures for highly-efficient photocatalytic hydrogen generation

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Journal of Energy Chemistry 2024年第10期97卷 379-387,I0008页

作者： xu Guo Xing Liu jing Shan Zhuo xu Zhiming Fang Lu Wang Shengzhong Liu School of Energy Powerand Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China Shaanxi Key Laboratory for Advanced Energy Devices School of Materials Science and EngineeringShanxi Normal UniversityXi'an 710119ShanxiChina Qinghai Advanced Energy Storage Laboratory SPIC Qinghai Photovoltaic Industry Innovation Center Co.Ltd.State Power Investment CorporationXining 810oo7QinghaiChina Key Laboratory of Photoelectric Conversion and Utilization of Solar Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen ***,2D/2D WSe_(2)/ZnIn_(2)S_(4) heterostructures with strong hetero-interface interaction and abundant contact were constructed via an impregnation-annealing *** charge transfer from ZnIn_(2)S_(4) to WSe_(2)was evidenced by transient absorption spectroscopy in crafted heterostructures owing to the tight and2D face-to-face *** a result,the prepared WSe_(2)/ZnIn_(2)S_(4) heterostructures exhibited boosted photocatalytic performance and a highest hydrogen evolution rate of 3.377 mmol/(g h)was achieved with an apparent quantum yield of 45.7%at 420 *** work not only provides new strategies to achieve efficient 2D/2D heterostructures but also paves the way for the development of green hydrogen in the future.

关键词： Strong hetero-interface interaction in 2D/2D WSe_(2)/ZnIn_(2)S_(4) heterostructures for highly-efficient photocatalytic hydrogen generation

Unsaturated bi-heterometal clusters in metal-vacancy sites of 2D MoS2 for efficient hydrogen evolution

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Carbon Energy 2024年第3期6卷 264-275页

作者： Gonglei Shao Jie xu Shasha Gao Zhang Zhang Song Liu xu Zhang Zhen Zhou Interdisciplinary Research Center for Sustainable Energy Science and Engineering(IRC4SE2) School of Chemical EngineeringZhengzhou UniversityZhengzhouHenanChina College of Chemistry and Materials Engineering Wenzhou UniversityWenzhouZhejiangChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjinChina State Key Laboratory of Chemo/Biosensing and Chemometrics Institute of Chemical Biology and Nanomedicine(ICBN)College of Chemistry and Chemical EngineeringHunan UniversityChangshaHunanChina Institute of New Energy Material Chemistry School of Materials Science and EngineeringNankai UniversityTianjinChina

The valence states and coordination structures of doped heterometal atoms in two-dimensional(2D)nanomaterials lack predictable regulation ***,a robust method is proposed to form unsaturated heteroatom clusters via the metal-vacancy restraint mechanism,which can precisely regulate the bonding and valence state of heterometal atoms doped in 2D molybdenum *** unsaturated valence state of heterometal Pt and Ru cluster atoms form a spatial coordination structure with Pt–S and Ru–O–S as catalytically active *** them,the strong binding energy of negatively charged suspended S and O sites for H+,as well as the weak adsorption of positively charged unsaturated heterometal atoms for H*,reduces the energy barrier of the hydrogen evolution reaction proved by theoretical ***,the electrocatalytic hydrogen evolution performance is markedly improved by the ensemble effect of unsaturated heterometal atoms and highlighted with an overpotential of 84 mV and Tafel slope of 68.5 mV dec^(−1).In brief,this metal vacancy-induced valence state regulation of heterometal can manipulate the coordination structure and catalytic activity of heterometal atoms doped in the 2D atomic lattice but not limited to 2D nanomaterials.

关键词： clusters hydrogen evolution reaction metal vacancy MoS2 unsaturated heterometal

Exhaustive review of acceleration strategies for Monte Carlo simulations in photon transit

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 5-21页

作者： Louzhe xu Zijie Zhu Ting Li Institute of Biomedical Engineering Chinese Academy of Medical Sciences&Peking Union Medical College Tianjin 300192 P.R.China

Monte Carlo simulation techniques have become the quintessence and a pivotal nexus of inquiry in the realm of simulating photon movement within biological *** the stochastic sampling of tissue archetypes delineated by explicit optical characteristics,Monte Carlo simulations possess the theoretical capacity to render unparalleled accuracy in the depiction of exceedingly intricate ***,the quintessential challenge associated with Monte Carlo simulation methodologies resides in their extended computational duration,which significantly impedes the re¯nement of their ***,this discourse is speci¯cally dedicated to exploring innovations in strategies and technologies aimed at expediting Monte Carlo *** delves into the foundational concepts of various acceleration tactics,evaluates these strategies concerning their speed,accuracy,and practicality,and amalgamates a comprehensive overview and critique of acceleration methodologies for Monte Carlo ***,the discourse envisages prospective trajectories for the employment of Monte Carlo techniques within the domain of tissue optics.

关键词： Medical optics photon transport simulation Monte Carlo simulation acceleration

基于扫频光谱测量技术的快速高精度折射率传感系统

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光通信技术 2020年第8期44卷 10-13页

作者：刘茂环樊昕昱王彬徐炳鑫何祖源长飞光纤光缆股份有限公司光纤光缆制备技术国家重点实验室武汉430074 上海交通大学区域光纤通信网与新型光通信系统国家重点实验室上海200240

为达到医学、化学等不同领域对高精度折射率测量的较高要求,基于高精度扫频光谱测量技术,结合倾斜光纤光栅进行折射率测量,提出实现高精度折射率变化传感系统。对倾斜光纤光栅截止模进行了细微差别折射率下的光谱测量,测得折射率响应灵... 详细信息

为达到医学、化学等不同领域对高精度折射率测量的较高要求,基于高精度扫频光谱测量技术,结合倾斜光纤光栅进行折射率测量,提出实现高精度折射率变化传感系统。对倾斜光纤光栅截止模进行了细微差别折射率下的光谱测量,测得折射率响应灵敏度为28.3 nm/RIU;对系统在固定折射率下对测量截止模光峰值中心波长的精度进行标定,算出系统的测量精度为1.15×10^-6 RIU,在静态测量情况下测量精度可以达到6.5×10^-7 RIU。

关键词：光谱测量折射率传感光纤光栅高精度