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Qualitative properties and classification of solutions to elliptic equations with Stein-Weiss type convolution part

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Science China Mathematics 2022年第10期65卷 2123-2150页

作者： Xiang Li minbo yang Xianmei Zhou Department of Mathematics Zhejiang Normal UniversityJinhua 321004China

In this paper,we study the qualitative properties and classification of the solutions to the elliptic equations with Stein-Weiss type convolution part.Firstly,we study the qualitative properties,such as the symmetry,regularity and asymptotic behavior of the positive solutions.Secondly,we classify the non-positive solutions by proving some Liouville type theorems for the finite Morse index solutions and stable solutions to the nonlocal elliptic equations with double weights.

关键词： weighted elliptic equation finite Morse index solution Liouville type theorems qualitative properties

Global multiplicity of solutions to a defocusing quasilinear Schrodinger equation with the singular term

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Science China Mathematics 2023年第8期66卷 1789-1812页

作者： Siyu Chen Carlos Alberto Santos minbo yang Jiazheng Zhou Department of Mathematics Zhejiang Normal UniversityJinhua 321004China Departamento de Matematica Universidade de BrasiliaBraslia 70910-900Brazil

We consider a class of modified quasilinear Schrodinger equations-△u+k/2u△u^(2)=λα(x)u^(-α)+b(x)u^(β) in Ω with u(x)=0 on■Ω,where Ω■R^(N)is a bounded domain with a regular boundary,N≥3,a and b are bounded mensurable functions,0<α<1<β<2*-1 and k,λ≥0 are two parameters.We establish the global existence and multiplicity results of positive solutions in H^(1)_(0)(Ω)∩L^(∞)(Ω)for appropriate classes of parameters k andλand coefficients a(x)and b(x).

关键词： quasilinear Schrodinger equation singular term square diffusion term

Coupling pinch analysis and rigorous process simulation for hydrogen networks with light hydrocarbon recovery

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Chinese Journal of Chemical Engineering 2021年第12期34卷 141-148页

作者： minbo yang Xiao Feng Liang Zhao Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi'an 710049China Key Laboratory of Advanced Control and Optimization for Chemical Processes East China University of Science and TechnologyMinistry of EducationShanghai 200237China

In refineries,some hydrogen-rich streams contain considerable light hydrocarbons that are important raw materials for the chemical industry.Integrating hydrogen networks with light hydrocarbon recovery can enhance the reuse of both hydrogen and light hydrocarbons.This work proposes an automated method for targeting hydrogen networks with light hydrocarbon recovery.A pinch-based algebraic method is improved to determine the minimum fresh hydrogen consumption and hydrogen sources fed into the light hydrocarbon recovery unit automatically.Rigorous process simulation is conducted to determine the mass and energy balances of the light hydrocarbon recovery process.The targeting procedures are developed through combination of the improved pinch method and rigorous process simulation.This hybrid method is realized by coupling the Matlab and Aspen HYSYS platforms.A refinery hydrogen network is analyzed to illustrate application of the proposed method.The integration of hydrogen network with light hydrocarbon recovery further reduces fresh hydrogen requirement by463.0 m^(3)·h^(-1) and recovers liquefied petroleum gas and gasoline of 1711.5 kg·h^(-1) and 643 kg·h^(-1),respectively.A payback period of 9.2 months indicates that investment in light hydrocarbon recovery is economically attractive.

关键词： Hydrogen Light hydrocarbon recovery Pinch technology Simulation Systems engineering

A unified graphical method for integration of hydrogen networks with purification reuse

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Chinese Journal of Chemical Engineering 2016年第7期24卷 891-896页

作者： minbo yang Xiao Feng Guilian Liu School of Chemical Engineering & Technology Xi' an Jiaotong University Xi' an 710049 China

Introducing purifiers into hydrogen network can enhance the recovery and reuse of hydrogen in refineries,further reducing the consumption of fresh hydrogen. Based on previous graphical methods, this work proposes a simple and unified graphical method for integration of hydrogen networks with purification processes.Scenarios with different hydrogen concentrations of purified product can be analyzed by the unified procedure.As a result, the maximum hydrogen saved by purification reuse can be identified and the corresponding purification process can be optimized. The proposed method is easy and non-iterative, and it is valid to purification processes with any feed concentration. A conventional hydrogen network is analyzed to test the effectiveness of the proposed method.

关键词：炼厂氢气净化回用集成方法网络图解法纯化过程回收利用净化过程

The Brezis-Nirenberg type critical problem for the nonlinear Choquard equation

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Science China Mathematics 2018年第7期61卷 1219-1242页

作者： Fashun Gao minbo yang Department of Mathematics Zhejiang Normal University

We establish some existence results for the Brezis-Nirenberg type problem of the nonlinear Choquard equation -Δu=(integral ((|u(y)|^(2*)_μ/|x-y|~μ)dy) from Ω )|μ|^(2*_μ-2_u)+λu in Ω where Ω is a bounded dotain of R^N with Lipschitz boundary, λ is a real parameter, N≥3,2_μ~*=(2 N-μ)/(N-2)is the critical exponent in the sense of the Hardy-Littlewood-Sobolev inequality.

关键词：非线性类型方程 Lipschitz

On a Class of Infinite-Dimensional Hamiltonian Systems with Asymptotically Periodic Nonlinearities

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Chinese Annals of Mathematics,Series B 2011年第1期32卷 45-58页

作者： minbo yang Zifei SHEN Yanheng DING Department of Mathematics Zhejiang Normal University Jinhua 321004 Zhejiang China Institute of Mathematics AMSS Chinese Academy of Sciences Beijing 100}90 China

The authors study the existence of homoclinic type solutions for the following system of diffusion equations on R × RN:{■tu-xu + b ·▽xu + au + V(t,x)v = Hv(t,x,u,v),-■tv-xv-b·▽xv + av + V(t,x)u = Hu(t,x,u,v),where z =(u,v):R × RN → Rm × Rm,a > 0,b =(b1,···,bN) is a constant vector and V ∈ C(R × RN,R),H ∈ C1(R × RN × R2m,R).Under suitable conditions on V(t,x) and the nonlinearity for H(t,x,z),at least one non-stationary homoclinic solution with least energy is obtained.

关键词：哈密顿系统非线性渐近周期无穷维注册商标研究开发扩散方程常数向量

脊柱内镜下单侧椎板间入路双侧椎管减压术对腰椎管狭窄症患者腰椎功能的改善效果

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中国临床研究 2024年第5期37卷 714-718页

作者：江民波李洋王德国黄凯田纪伟上海交通大学医学院附属松江医院骨科上海201699

目的分析脊柱内镜下单侧椎板间入路双侧椎管减压术改善腰椎管狭窄症(LSS)患者腰椎功能的效果。方法选择2021年8月至2023年8月到上海交通大学医学院附属松江医院诊治的LSS患者82例,利用随机数字表法分组,实施脊柱内镜下经皮椎间孔入路椎... 详细信息

目的分析脊柱内镜下单侧椎板间入路双侧椎管减压术改善腰椎管狭窄症(LSS)患者腰椎功能的效果。方法选择2021年8月至2023年8月到上海交通大学医学院附属松江医院诊治的LSS患者82例,利用随机数字表法分组,实施脊柱内镜下经皮椎间孔入路椎管减压术治疗的41例患者纳入对照组,实施脊柱内镜下单侧椎板间入路双侧椎管减压术治疗的41例患者纳入研究组。对比两组的手术指标、腰椎功能、疼痛程度、影像学指标、椎管微炎症因子、氧化应激指标、治疗效果及并发症。结果研究组手术时间、卧床时间短于对照组,术中出血量少于对照组(P<0.05)。术后,研究组突出物侵占比低于对照组,椎管面积大于对照组(P<0.05)。术后24 h,研究组单核细胞趋化蛋白-1(MCP-1)、白细胞介素(IL)-1β、IL-1α及血清丙二醛(MDA)低于对照组(P<0.05),超氧化物歧化酶(SOD)及谷胱甘肽过氧化物酶(GSH-Px)水平高于对照组(P<0.05)。研究组MacNab优良率高于对照组(92.68%vs 75.61%,χ^(2)=4.479,P<0.05),并发症总发生率低于对照组(4.88%vs 19.51%,χ^(2)=4.100,P<0.05)。结论对于LSS患者,经皮椎间孔入路与单侧椎板间入路均取得良好的效果,但脊柱内镜下单侧椎板间入路双侧椎管减压术的效果更佳,有利于改善腰椎功能,减轻腰椎疼痛程度、椎管微炎症损伤和氧化应激损伤,减少并发症的发生。

关键词：腰椎管狭窄症脊柱内镜下单侧椎板间入路双侧椎管减压术腰椎功能椎管微炎症因子

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近距离煤层回采巷道非对称破坏机理及其控制

采矿与安全工程学报 2024年第2期41卷 242-254页

作者：丁自伟李帅张杰蔡敏博李亮姬东康萌西安科技大学能源学院陕西西安710054 陕西陕煤韩城矿业有限公司下峪口煤矿陕西渭南714000 陕西煤业化工技术研究院有限责任公司陕西西安710199

近距离煤层开采时,上位煤层的遗留煤柱集中应力会对下位煤层邻近采空区的巷道掘进产生扰动影响。针对下峪口煤矿3#_(下)煤层回采巷道掘进时产生的非对称变形破坏及支护困难等问题,结合现场地质条件,采用力学分析、数值模拟和现场试验的... 详细信息

近距离煤层开采时,上位煤层的遗留煤柱集中应力会对下位煤层邻近采空区的巷道掘进产生扰动影响。针对下峪口煤矿3#_(下)煤层回采巷道掘进时产生的非对称变形破坏及支护困难等问题,结合现场地质条件,采用力学分析、数值模拟和现场试验的方法,探究23306下进风巷掘进期间产生的非对称变形机理,并提出合理的巷道支护参数及工艺,改善了巷道围岩条件。研究结果表明:上位煤层遗留煤柱及本煤层邻近采空区的存在导致巷道围岩主应力方向及大小发生变化,而非均匀的应力分布致使巷道围岩塑性区呈现蝶形破坏,巷道顶板水平应力变化幅度大、剪切应力大,造成巷道顶板极度破碎,顶板至上覆采空区间全为塑性区分布,顶板两侧应力及塑性区的差异性分布是造成巷道非对称变形的主要原因;数值模拟得到煤柱内X-Y,X-Z,Z-Z方向的应力受本煤层邻近采空区的影响较大,巷道两侧应力大小不等,致使巷道产生非对称变形;根据巷道围岩的受力状态、工作面地质条件及支护成本,优化了巷道支护参数,现场应用效果良好。

关键词：近距离煤层回采巷道非对称变形蝶形破坏围岩控制

激光粉末床熔融Inconel718合金工艺优化与组织演变

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中国粉体技术 2024年第1期30卷 23-35页

作者：刘阳徐靖宁挺杨洪宇谭振国郭世柏王敏卜湖南科技大学机电工程学院高功效轻合金构件成形技术及耐损伤性能评价湖南省工程研究中心湖南湘潭411201 湖南西交智造科技有限公司湖南湘潭411100

【目的】分析能量密度对激光粉末床熔融镍铁基高温合金(Inconel718,IN718)显微组织的主要影响,以期提高激光粉末床熔融IN718的致密度。【方法】采用田口方法和方差分析方法优化激光功率、扫描速度、扫描间距,得到高致密合金样品激光功率... 详细信息

【目的】分析能量密度对激光粉末床熔融镍铁基高温合金(Inconel718,IN718)显微组织的主要影响,以期提高激光粉末床熔融IN718的致密度。【方法】采用田口方法和方差分析方法优化激光功率、扫描速度、扫描间距,得到高致密合金样品激光功率-扫描速度-扫描间距的关系模型,并对模型得到的结果进行验证。【结果】扫描间距对样品的相对密度影响最大,贡献率为38.31%;在研究范围内,熔池尺寸与体能量密度成正比,Al和Ti元素在晶界处有明显的微观偏析,能促进液膜开裂,从而导致裂纹等缺陷的形成。【结论】设计的模型将有助于建立一种高效的LPBF制备Inconel718合金工艺。

关键词：激光粉末床熔融镍铁基高温合金显微组织元素偏析