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利用不变集方法求(2+1)维拟线性扩散方程的精确解

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西北大学学报（自然科学版） 2010年第4期40卷 576-578,582页

作者：屈改珠渭南师范学院数学系陕西渭南714000

目的构造(2+1)维拟线性扩散方程的精确解。方法利用不变集方法。结果得到了(2+1)维拟线性扩散方程的一些精确解。结论该方法也可以用来解决其他非线性方程。

关键词：拟线性扩散方程不变集精确解

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一类非线性色散方程组的不变子空间和精确解

西北大学学报（自然科学版） 2014年第5期44卷 705-708页

作者：屈改珠西北大学数学学院陕西西安710127 渭南师范学院数学与信息科学学院陕西渭南714000

研究孤立子理论中非常重要的一类非线性色散演化方程组。利用不变子空间方法。确定出非线性色散方程组在它所容许的不变子空间W13×W22中的完全分类,并构造相应的精确解。文中的结果丰富和推广了不变子空间理论在非线性偏微分方程中的... 详细信息

研究孤立子理论中非常重要的一类非线性色散演化方程组。利用不变子空间方法。确定出非线性色散方程组在它所容许的不变子空间W13×W22中的完全分类,并构造相应的精确解。文中的结果丰富和推广了不变子空间理论在非线性偏微分方程中的应用。

关键词：不变子空间非线性色散演化方程组广义分离变量解

(1+1)维带有热源项的非线性波动方程的精确解

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西北大学学报（自然科学版） 2012年第6期42卷 882-884页

作者：屈改珠渭南师范学院数学与信息科学学院陕西渭南714000

目的讨论(1+1)维带有热源项的非线性波动方程特殊情况的解。方法利用不变集的思想方法。结果得到了上述方程的一些精确解。结论该方法也可以用来解决其他非线性偏微分方程。

关键词：非线性波动方程不变集精确解

Stress-strain relationship for reactive powder concrete with recycled powder under uniaxial compression

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1015-1027页

作者： Peng zhu Yunming zhu Wenjun qu Liyu XIE College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji UniversityShanghai 200092China

The recycled powder(RP)from construction wastes can be used to partially replace cement in the preparation of reactive powder *** this paper,reactive powder concrete mixtures with RP partially replacing cement,and natural sand instead of quartz,are *** curing is used,instead of steam curing that is normally requested by standard for reactive powder *** influences of RP replacement ratio(0%,10%,20%,30%),silica fume proportion(10%,15%,20%),and steel fiber proportion(0%,1%,2%)are *** effects of RP,silica fume,and steel fiber proportion on compressive strength,elastic modulus,and relative absorption energy are analyzed,and theoretical models for compressive strength,elastic modulus,and relative absorption energy are established.A constitutive model for the uniaxial compressive stress-strain relationship of reactive powder concrete with RP is *** the increase of RP replacement ratio from 0% to 30%,the compressive strength decreases by 42% and elastic modulus decreases by 24%.

关键词： recycled powder reactive powder concrete elastic modulus relative absorbed energy stress-strain relationship

一类非线性耗散方程组的不变子空间及其精确解

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数学的实践与认识 2015年第22期45卷 243-248页

作者：屈改珠渭南师范学院数学与信息科学学院陕西渭南714000 西北大学数学学院陕西西安710069

利用不变子空间方法研究一类在孤立子理论中具有广泛应用的非线性耗散方程组,确定出非线性耗散方程组在它所容许的不变子空间W3^1×W2^2中的完全分类,构造了方程组的精确解或者将方程组约化为有限维动力系统.文中的结果进一步推广了不... 详细信息

利用不变子空间方法研究一类在孤立子理论中具有广泛应用的非线性耗散方程组,确定出非线性耗散方程组在它所容许的不变子空间W3^1×W2^2中的完全分类,构造了方程组的精确解或者将方程组约化为有限维动力系统.文中的结果进一步推广了不变子空间理论在非线性偏微分方程中的应用.

关键词：不变子空间非线性耗散方程组广义分离变量解

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高阶非线性薄膜方程的李对称分析

西北师范大学学报（自然科学版） 2016年第6期52卷 18-21,37页

作者：屈改珠渭南师范学院数理学院陕西渭南714000

利用李群分析方法研究了高阶非线性薄膜方程.首先,利用无穷小生成元方法得到了该方程的李代数及其最优系统,然后对方程进行约化,最后获得了一些具有特定物理意义的相似解.

关键词：高阶非线性薄膜方程李对称分析不变解

(1+1)维带有对流项和源项的非线性扩散方程的新精确解

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西北师范大学学报（自然科学版） 2010年第4期46卷 10-11,18页

作者：屈改珠渭南师范学院数学系陕西渭南714000

讨论了(1+1)维带有对流项和源项的非线性扩散方程特殊情况的解.利用不变集的思想方法,得到了上述方程的几个新精确解.

关键词：反应扩散方程不变集精确解

Extending homogeneous fluidization flow regime of Geldart-A particles by exerting axial uniform and steady magnetic field

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Chinese Journal of Chemical Engineering 2024年第1期65卷 169-177页

作者： Qiang Zhang Wankun Liu Hengjun gai quanhong zhu College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China School of Chemical&Environmental Engineering China University of Mining&Technology-BeijingBeijing 100083China

The homogeneous/particulate fluidization flow regime is particularly suitable for handling the various gas–solid contact processes encountered in the chemical and energy *** work aimed to extend such a regime of Geldart-A particles by exerting the axial uniform and steady magnetic *** the action of the magnetic field,the overall homogeneous fluidization regime of Geldart-A magnetizable particles became composed of two parts:inherent homogeneous fluidization and newly-created magnetic *** the former remained almost unchanged whereas the latter became broader as the magnetic field intensity increased,the overall homogeneous fluidization regime could be extended *** for Geldart-A nonmagnetizable particles,certain amount of magnetizable particles had to be premixed to transmit the magnetic *** others,the mere addition of magnetizable particles could broaden the homogeneous fluidization *** added content of magnetizable particles had an optimal value with smaller/lighter ones working *** added magnetizable particles might raise the ratio between the interparticle force and the particle *** the magnetic field was exerted,the homogeneous fluidization regime was further expanded due to the formation of magnetic stabilization flow *** more the added magnetizable particles,the better the magnetic performance and the broader the overall homogeneous fluidization ***/lighter magnetizable particles were preferred to maximize the magnetic performance and extend the overall homogeneous fluidization *** phenomenon could be ascribed to that the added magnetizable particles themselves became more Geldart-A than-B type as their density or size decreased.

关键词： Fluidized-bed Fluidization Geldart-A particles Flow regimes Extend Magnetic stabilization

Mobility of rhenium and selenium during chemical weathering and their implication for petrogenic organic carbon oxidation

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Science China Earth Sciences 2024年第3期67卷 740-750页

作者： Yuhong ZHANG Jin WANG Yuanxin qu Chao zhu Zhangdong JIN State Key Laboratory of Loess and quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China

The oxidative weathering of petrogenic organic carbon(OC_(petro)) is an important source of carbon dioxide(CO_(2)) into the atmosphere on geological timescales and significantly influences the carbon cycle and global climate change. However, at present, a robust proxy to assess OC_(petro)oxidation is lacking. Riverine rhenium(Re) has emerged as a potential proxy to trace OC_(petro)oxidation, but little is known about Re sources and its relationship with OC_(petro)oxidation. To better understand the robustness of this proxy, we analyzed a shale weathering profile from the early Cambrian Shuijingtuo Formation in Chengkou County, Chongqing City, to address the mobility of Re and selenium(Se) and their relationship with the oxidation of OC_(petro)by analyses of the elemental variation and sequential extraction. The results showed that the chemical index of alteration(CIA)increases from the fresh bedrock to the weathered sections, indicating enhanced weathering intensity. Based on the sequential extraction and mass transfer coefficients(τ), Re and Se mainly exist in the organic phase of shale and are paired lost with OC_(petro) during weathering, with no obvious correlation with sulfide minerals. Furthermore, the different proportions of Re and Se loss with OC_(petro) loss can be attributed to their different geochemical behaviors during weathering. Our study supports Re as a robust proxy to trace OC_(petro) oxidation, whereas Se is the potential one. In the future, combined studies on various sedimentary rock profiles with catchment basins are needed to determine the sources of riverine Re and Se and their relationships with OC_(petro) oxidation.

关键词： Rhenium and selenium Shale Mobility OC_(petro) Chemical weathering