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THE GLOBAL EXISTENCE AND UNIQUENESS OF SMOOTH SOLUTIONS TO A FLUID-PARTICLE INTERACTION MODEL IN THE FLOWING REGIME
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作者 Lin ZHENG Shu WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1877-1885,共9页
This paper is concerned with the Cauchy problem for a 3D fluid-particle interaction model in the so-called flowing regime inℝ3.Under the smallness assumption on both the external potential and the initial perturbation... This paper is concerned with the Cauchy problem for a 3D fluid-particle interaction model in the so-called flowing regime inℝ3.Under the smallness assumption on both the external potential and the initial perturbation of the stationary solution in some Sobolev spaces,the existence and uniqueness of global smooth solutions in H3 of the system are established by using the careful energy method. 展开更多
关键词 fluid-particle flowing regime global existence
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THE GLOBAL EXISTENCE OF STRONG SOLUTIONS TO THERMOMECHANICAL CUCKER-SMALE-STOKES EQUATIONS IN THE WHOLE DOMAIN
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作者 邹委员 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期887-908,共22页
We study the global existence and uniqueness of a strong solution to the kinetic thermomechanical Cucker-Smale(for short,TCS) model coupled with Stokes equations in the whole space.The coupled system consists of the k... We study the global existence and uniqueness of a strong solution to the kinetic thermomechanical Cucker-Smale(for short,TCS) model coupled with Stokes equations in the whole space.The coupled system consists of the kinetic TCS equation for a particle ensemble and the Stokes equations for a fluid via a drag force.In this paper,we present a complete analysis of the existence of global-in-time strong solutions to the coupled model without any smallness restrictions on the initial data. 展开更多
关键词 thermomechanical Cucker-Smale model Stokes equations strong solutions global existence
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Effect of burial depth of a new tunnel on the seismic response of an existing tunnel
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作者 Ma Runbo Cao Qikun +3 位作者 Lu Shasha Zhao Dongxu Zhang Yanan Xu Hong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期863-882,共20页
Burial depth is a crucial factor affecting the forces and deformation of tunnels during earthquakes.One key issue is a lack of understanding of the effect of a change in the buried depth of a single-side tunnel on the... Burial depth is a crucial factor affecting the forces and deformation of tunnels during earthquakes.One key issue is a lack of understanding of the effect of a change in the buried depth of a single-side tunnel on the seismic response of a double-tunnel system.In this study,shaking table tests were designed and performed based on a tunnel under construction in Dalian,China.Numerical models were established using the equivalent linear method combined with ABAQUS finite element software to analyze the seismic response of the interacting system.The results showed that the amplification coefficient of the soil acceleration did not change evidently with the burial depth of the new tunnel but decreased as the seismic amplitude increased.In addition,the existing tunnel acceleration,earth pressure,and internal force were hardly affected by the change in the burial depth;for the new tunnel,the acceleration and internal force decreased as the burial depth increased,while the earth pressure increased.This shows that the earth pressure distribution in a double-tunnel system is relatively complex and mainly concentrated on the arch spandrel and arch springing of the relative area.Overall,when the horizontal clearance between the center of the two tunnels was more than twice the sum of the radius of the outer edges of the two tunnels,the change in the burial depth of the new tunnel had little effect on the existing one,and the tunnel structure was deemed safe.These results provide a preliminary understanding and reference for the seismic performance of a double-tunnel system. 展开更多
关键词 burial depth new tunnel existing tunnel seismic response shaking table tests numerical simulations
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The Existence of Solutions for Kirchhoff-Type Equations with General Singular Terms
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作者 WANG Ji-nan SUN Da-wei 《Chinese Quarterly Journal of Mathematics》 2024年第3期315-323,共9页
We study the existence of solutions for Kirchhoff-type equations.Firstly,we use the Sobolev inequality and the weakly lower semi-continuity of the norm to prove that the corresponding function can reach the global min... We study the existence of solutions for Kirchhoff-type equations.Firstly,we use the Sobolev inequality and the weakly lower semi-continuity of the norm to prove that the corresponding function can reach the global minimum.Then,we use the variational method and some analytical techniques to obtain the existence of the positive solution of the equation whenλis small enough. 展开更多
关键词 Kirchhoff-type equation The existence Positive solution Variational method
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Durability evaluation for existing railway engineering: a review
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作者 Jiahe Wang Huajian Li +3 位作者 Chengxian Ma Chaoxun Cai Zhonglai Yi Jiaxuan Wang 《Railway Sciences》 2024年第1期59-68,共10页
Purpose – This study aims to analyze the factors, evaluation techniques of the durability of existing railwayengineering.Design/methodology/approach – China has built a railway network of over 150,000 km. Ensuring t... Purpose – This study aims to analyze the factors, evaluation techniques of the durability of existing railwayengineering.Design/methodology/approach – China has built a railway network of over 150,000 km. Ensuring thesafety of the existing railway engineering is of great significance for maintaining normal railway operationorder. However, railway engineering is a strip structure that crosses multiple complex environments. Andrailway engineering will withstand high-frequency impact loads from trains. The above factors have led todifferences in the deterioration characteristics and maintenance strategies of railway engineering compared toconventional concrete structures. Therefore, it is very important to analyze the key factors that affect thedurability of railway structures and propose technologies for durability evaluation.Findings – The factors that affect the durability and reliability of railway engineering are mainly divided intothree categories: material factors, environmental factors and load factors. Among them, material factors alsoinclude influencing factors, such as raw materials, mix proportions and so on. Environmental factors varydepending on the service environment of railway engineering, and the durability and deterioration of concretehave different failure mechanisms. Load factors include static load and train dynamic load. The on-site rapiddetection methods for five common diseases in railway engineering are also proposed in this paper. Thesemethods can quickly evaluate the durability of existing railway engineering concrete.Originality/value – The research can provide some new evaluation techniques and methods for thedurability of existing railway engineering. 展开更多
关键词 Durability assessment existing railway engineering Evaluation techniques
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Existence of Entropy Solution for Degenerate Parabolic-Hyperbolic Problem Involving p(x)-Laplacian with Neumann Boundary Condition
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作者 Mohamed Karimou Gazibo Duni Yegbonoma Frédéric Zongo 《Applied Mathematics》 2024年第7期455-463,共9页
We consider a strongly non-linear degenerate parabolic-hyperbolic problem with p(x)-Laplacian diffusion flux function. We propose an entropy formulation and prove the existence of an entropy solution.
关键词 Lebesgue and Sobolev Spaces with Variable Exponent Weak Solution Entropy Solution Degenerate Parabolic-Hyperbolic Equation Conservation Law Leray Lions Type Operator Neumann Boundary Condition existence Result
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The Inner Split in Genetics of Wu Colloquial Expression“[hÃɲ^(33) paʔ^(3) lÃɲ^(33) tÃɲ^(31)]”
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作者 SONG Jia-fu 《Journal of Literature and Art Studies》 2024年第9期794-801,共8页
“[ã^(44) kã^(44) paʔ^(5) lã44 tã^(53)]”(Chinese characters transcription“昂更八冷打”)is an colloquial expression in Tongxiang dialect of Suzhou-Jiaxing-Huzhou Sub-branch,Taihu Branch,Wu.It describes an awkward... “[ã^(44) kã^(44) paʔ^(5) lã44 tã^(53)]”(Chinese characters transcription“昂更八冷打”)is an colloquial expression in Tongxiang dialect of Suzhou-Jiaxing-Huzhou Sub-branch,Taihu Branch,Wu.It describes an awkward state with unfinished tasks.Its similar expressions can be found in other regions of Taihu Branch,including Yixing,Changzhou,Shaoxing and Ningbo,usually serving as“all”,while the expression“[hÃɲ^(33) paʔ^(3) lÃɲ^(33) tÃɲ^(31)]”(“亨八冷打”)in Shanghai Sub-branch indicates“the remaining parts”when used alone.“[hÃɲ^(33) paʔ^(3) lÃɲ^(33) tÃɲ^(31)]”stands for“all”only when followed by a word with meaning of“adding together”.In this paper,it is concluded and deduced from other similar morphemes that the contradictory connotations are related to an“inner split”process of an original word.Considering similar morphemes in other Chinese dialects(including Cantonese,Hakka,Jianghuai and Min),the following analysis proposes three possible original expressions and correlating trajectories of this inner phonetic-semantic split process,and selects a most credible way based on the rhyming dictionary and previous reconstructive models of ancient Chinese phonology.This presumptive analysis indicates that a broader“split and derivate”process generating new morphemes exists widely in Sinitic dialects as a natural company of phonetic features in Chinese language flow. 展开更多
关键词 wu Middle-ancient Chinese phonology Chinese dialect inner split
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The Relationship between Dachuan Baijie Muddymen Dance and“Da Xia”and“Da Wu”
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作者 MA Lei 《Journal of Literature and Art Studies》 2024年第9期765-768,共4页
Dachuan Baijie Muddymen Dance is a kind of dance with local characteristics.From its dance movements and prop usage,it should be related to ancient Ba people’s war dance,as well as to recorded ancient dances such as... Dachuan Baijie Muddymen Dance is a kind of dance with local characteristics.From its dance movements and prop usage,it should be related to ancient Ba people’s war dance,as well as to recorded ancient dances such as“Da Xia”and“Da Wu”. 展开更多
关键词 Muddymen Dance Ba people war dance “Da Xia” “Da wu
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Existence of Solutions of a Convolution Integral Equation
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作者 Henry Otoo Benjamin Dadzie Mensah Lewis Brew 《Journal of Applied Mathematics and Physics》 2024年第5期1835-1847,共13页
In this study, we prove the of existence of solutions of a convolution Volterra integral equation in the space of the Lebesgue integrable function on the set of positive real numbers and with the standard norm defined... In this study, we prove the of existence of solutions of a convolution Volterra integral equation in the space of the Lebesgue integrable function on the set of positive real numbers and with the standard norm defined on it. An operator P was assigned to the convolution integral operator which was later expressed in terms of the superposition operator and the nonlinear operator. Given a ball B<sub>r</sub> belonging to the space L it was established that the operator P maps the ball into itself. The Hausdorff measure of noncompactness was then applied by first proving that given a set M∈ B r the set is bounded, closed, convex and nondecreasing. Finally, the Darbo fixed point theorem was applied on the measure obtained from the set E belonging to M. From this application, it was observed that the conditions for the Darbo fixed point theorem was satisfied. This indicated the presence of at least a fixed point for the integral equation which thereby implying the existence of solutions for the integral equation. 展开更多
关键词 VOLTERRA Integral Equation CONVOLUTION Fixed Point existENCE Noncompactness
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Anti-inflammatory effects of Tao Hong Si Wu Tang in mice with lung cancer and chronic obstructive pulmonary disease
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作者 Guo-Li Wang Yan-Ling Xu +4 位作者 Ke-Ming Zhao Ai-Feng Sui Li-Na Wang Hu Deng Ge Wang 《World Journal of Clinical Oncology》 2024年第9期1198-1206,共9页
BACKGROUND Lung cancer(LC)combined with chronic obstructive pulmonary disease(COPD)is a common combination of comorbidities.Anti-inflammation and modulation of oxidative/antioxidative imbalance may prevent COPD-induce... BACKGROUND Lung cancer(LC)combined with chronic obstructive pulmonary disease(COPD)is a common combination of comorbidities.Anti-inflammation and modulation of oxidative/antioxidative imbalance may prevent COPD-induced LC,and are also crucial to the treatment of LC combined with COPD.Modern studies have shown that Tao Hong Si Wu Tang(THSW)has vasodilatory,anti-inflammatory,anti-fatigue,anti-shock,immunoregulatory,lipid-reducing,micronutrient-supplementing,and anti-allergy effects.AIM To observe the effects of THSW on COPD and LC in mice.METHODS A total of 100 specific pathogen-free C57/BL6 mice were randomly divided into five groups:Blank control group(group A),model control group(group B),THSW group(group C),IL-6 group(group D),and THSW+IL-6 group(group E),with 20 mice in each group.A COPD mouse model was established using fumigation plus lipopolysaccharide intra-airway drip,and an LC model was replicated by in situ inoculation using the Lewis cell method.RESULTS The blank control group exhibited a clear alveolar structure.The model control and IL-6 groups had thickened alveolar walls,with smaller alveolar lumens,interstitial edema,and several inflammatory infiltrating cells.Histopathological changes in the lungs of the THSW and THSW+IL-6 groups were less than those of the model control group.The serum IL-1β,IL-6,and TNF-αlevels and IL-6R,JAK,p-JAK,STAT1/3,p-STAT1/3,FOXO,p-FOXO,and IL-7R expression levels in lung tissues of mice in the rest of the groups were significantly higher than those of the blank control group(P<0.01).Compared with the model control group,the IL-6 group demonstrated significantly higher levels for the abovementioned proteins in the serum and lung tissues(P<0.01),and the THSW group had significantly higher serum IL-1β,IL-6,and TNF-αlevels and IL-7R expression levels in lung tissues(P<0.01)but significantly decreased IL-6R,JAK,p-JAK,STAT1/3,p-STAT1/3,FOXO,p-FOXO,and IL-7R levels(P<0.01).CONCLUSION THSW reduces the serum IL-1β,IL-6,and TNF-αlevels in the mouse model with anti-inflammatory effects.Its antiinflammatory mechanism lies in inhibiting the overactivation of the JAK/STAT1/3 signaling pathway. 展开更多
关键词 Tao Hong Si wu Tang Anti-inflammatory Chronic obstructive pulmonary disease Lung cancer Traditional Chinese medicine
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Operation optimization strategy of existing residential building energy-saving renovation market:From the perspective of subject behavior
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作者 GUO Han-ding LI Rui-jiao +1 位作者 QIN Guang-lei ZHANG Yin-xian 《Ecological Economy》 2024年第3期290-300,共11页
The energy-saving renovation of existing residential buildings is a crucial measure to achieve the strategic goal of energy conservation and emission reduction in China and build ecologically livable cities.This artic... The energy-saving renovation of existing residential buildings is a crucial measure to achieve the strategic goal of energy conservation and emission reduction in China and build ecologically livable cities.This article focuses on the perspective of subject behavior,starting from analyzing the current situation and difficulties of the operation of the energy-saving renovation market for existing residential buildings in China,drawing on the practical experience of the operation of the existing residential building energy-saving renovation market abroad.Based on principles such as systematicity,humanization,feasibility,and sustainability,the article constructs an operation optimization system of the existing residential building energy-saving renovation market from the perspective of subject behavior.In order to provide a reference for the healthy and orderly operation of the existing residential building energy-saving renovation market,this paper proposes implementation strategies for optimizing the operation of the existing residential building energy-saving renovation market.Suggestions are proposed from four aspects:optimizing the market environment,innovating the financing model,building the information sharing platform,and utilizing the synergies of the main subjects. 展开更多
关键词 the existing residential buildings energy-saving renovation market operation optimization strategy perspective of subject behavior
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Global Existence of the Solution for a Reduced Model of the Vectorial Quantum Zakharov System
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作者 Guiyu Yang 《Journal of Applied Mathematics and Physics》 2024年第2期533-542,共10页
In this paper, we study the global existence of the smooth solution for a reduced quantum Zakharov system in two spatial dimensions. Using energy estimates and the logarithmic type Sobolev inequality, we show the glob... In this paper, we study the global existence of the smooth solution for a reduced quantum Zakharov system in two spatial dimensions. Using energy estimates and the logarithmic type Sobolev inequality, we show the global existence of the solution to this system without any small condition on the initial data. 展开更多
关键词 Quantum Zakharov System Global existence Logarithmic Sobolev Inequality
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Global Existence and Decay of Solutions for a Class of a Pseudo-Parabolic Equation with Singular Potential and Logarithmic Nonlocal Source
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作者 Xiaoxin Yang 《Journal of Applied Mathematics and Physics》 2024年第1期181-193,共13页
This article investigates the well posedness and asymptotic behavior of Neumann initial boundary value problems for a class of pseudo-parabolic equations with singular potential and logarithmic nonlinearity. By utiliz... This article investigates the well posedness and asymptotic behavior of Neumann initial boundary value problems for a class of pseudo-parabolic equations with singular potential and logarithmic nonlinearity. By utilizing cut-off techniques and combining with the Faedo Galerkin approximation method, local solvability was established. Based on the potential well method and Hardy Sobolev inequality, derive the global existence of the solution. In addition, we also obtained the results of decay. 展开更多
关键词 Nonlocal Parabolic Equation Singular Potential Logarithmic Nonlocal Source Global existence DECAY
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-Point Boundary Value Problem Sign-Changing Green’s Function Fixed Point Index Iterative Technique Monotone Positive Solution existENCE
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ELASTIC MEMBRANE EQUATION WITH MEMORY TERM AND NONLINEAR BOUNDARY DAMPING:GLOBAL EXISTENCE,DECAY AND BLOWUP OF THE SOLUTION 被引量:2
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作者 Abderrahmane ZARA Nasser-eddine TATAR Salem ABDELMALEK 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期84-106,共23页
In this paper we consider the Elastic membrane equation:with memory term and nonlinear boundary damping: Under some appropriate assumptions on the relaxation function h and with certain initial data, the global exis... In this paper we consider the Elastic membrane equation:with memory term and nonlinear boundary damping: Under some appropriate assumptions on the relaxation function h and with certain initial data, the global existence of solutions :and a general decay for the energy are established using the multiplier technique. Also, 'we show that a nonlinear source of polynomial type is able to force solutions to blow up in finite time even in presence of a nonlinear damping. 展开更多
关键词 elastic membrane equation global existence boundary damping boundarysource general decay BLOwuP
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Research progress on chemical constituents and pharmacological activities of Amomum longiligulare T.L.Wu 被引量:1
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作者 QU Hui-juan OU Hong-ya +1 位作者 LIN Kai-wen WEI Na 《Journal of Hainan Medical University》 2023年第1期67-71,共5页
In order to develop and utilize the tropical medicinal resource Amomum(A.)longiligulare T.L.Wu more reasonably and effectively,this paper summarizes the research progress in chemical constituents and pharmacological a... In order to develop and utilize the tropical medicinal resource Amomum(A.)longiligulare T.L.Wu more reasonably and effectively,this paper summarizes the research progress in chemical constituents and pharmacological activities of A.longiligulare by consulting the literatures,so as to provide a certain theoretical basis for exploring its material basis.The chemical constituents of A.longiligulare mainly include volatile oil,diphenylheptane and flavonoids,which have good efficacy in anti-peptic ulcer,as well as antioxidant,analgesic and other pharmacological activities.This paper briefly discusses the reasons for the differences in the composition of volatile oil studied by different scholars.By summarizing its pharmacological activities,it is found that its various pharmacological activities may be the basis of its anti-peptic ulcer. 展开更多
关键词 Amomum longiligulare T.L.wu Chemical constituents Pharmacological activities
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THE EXISTENCE OF WEAK SOLUTIONS AND PROPAGATION REGULARITY FOR A GENERALIZED KDV SYSTEM
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作者 郭柏灵 肖亚敏 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期942-958,共17页
This paper examines the existence of weak solutions to a class of the high-order Korteweg-de Vries(KdV)system in Rn.We first prove,by the Leray-Schauder principle and the vanishing viscosity method,that any initial da... This paper examines the existence of weak solutions to a class of the high-order Korteweg-de Vries(KdV)system in Rn.We first prove,by the Leray-Schauder principle and the vanishing viscosity method,that any initial data N-dimensional vector value function u0(x)in Sobolev space H^(s)(R^(n))(s≥1)leads to a global weak solution.Second,we investigate some special regularity properties of solutions to the initial value problem associated with the KdV type system in R^(2)and R^(3). 展开更多
关键词 global existence propagation regularity KdV system
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THE EXISTENCE OF GLOBAL SOLUTIONS FOR THE FULL NAVIER-STOKES-KORTEWEG SYSTEM OF VAN DER WAALS GAS
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作者 Hakho HONG 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期469-491,共23页
The aim of this work is to prove the existence for the global solution of a nonisothermal or non-isentropic model of capillary compressible fluids derived by J.E.Dunn and J.Serrin(1985),in the case of van der Waals ga... The aim of this work is to prove the existence for the global solution of a nonisothermal or non-isentropic model of capillary compressible fluids derived by J.E.Dunn and J.Serrin(1985),in the case of van der Waals gas.Under the small initial perturbation,the proof of the global existence is based on an elementary energy method using the continuation argument of local solution.Moreover,the uniqueness of global solutions and large time behavior of the density are given.It is one of the main difficulties that the pressure p is not the increasing function of the densityρ. 展开更多
关键词 Navier-Stokes-Korteweg system van der Waals gas existENCE UNIQUENESS
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The existence of radial k-admissible solutions for n-dimension system of k-Hessian equations
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作者 HE Xing-yue WANG Jing-jing GAO Cheng-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第2期310-316,共7页
In this paper,we focus on a general n-dimension system of k-Hessian equations.By introducing some new suitable growth conditions,the existence results of radial k-admissible solutions of the k-Hessian system are obtai... In this paper,we focus on a general n-dimension system of k-Hessian equations.By introducing some new suitable growth conditions,the existence results of radial k-admissible solutions of the k-Hessian system are obtained.Our approach is largely based on the well-known fixed-point theorem. 展开更多
关键词 k-Hessian equations radial k-admissible solutions existENCE xed-point theorem
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Effect of existence state of asphaltenes on the asphaltenes-wax interaction in wax deposition
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作者 Yun Lei Han Wang +5 位作者 Shuang-Shuang Li Xue-Qian Liu Hao-Ran Zhu Yu-Ming Gao Hao-Ping Peng Peng-Fei Yu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期507-514,共8页
Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax i... Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax interaction.In this study,the concept of the existence state of asphaltenes was introduced to semi-quantitatively investigate the precipitation and aggregation characteristics of asphaltenes.On this basis,the influence of the existence state of asphaltenes on wax deposition was studied by coldfinger device and high-temperature gas chromatography,and the composition and properties of the deposits were analyzed.Four main findings were made:(1)As the asphaltene concentration increases,the existence state of asphaltenes gradually transitions from dispersed state to aggregated state,and the asphaltene concentration of 0.30 wt%in this study is the starting point of the transition.(2)The existence state of asphaltenes in crude oil does affect the process of wax deposition,as shown in the fact that the dispersed asphaltenes promote the occurrence of wax deposition,while the aggregated asphaltenes can inhibit wax deposition.(3)In the presence of the aggregated asphaltenes,that is,when the asphaltene concentration is higher than 0.30 wt%,the shedding phenomenon of deposit layer was observed,and with the increase of aggregated asphaltenes,the deposit layer fell off earlier.(4)With the increase of the dispersed asphaltenes,the wax appearance temperature(WAT)and wax content of the deposits all showed an increasing trend,while with the appearance of the aggregated asphaltenes,the above situation was reversed.The findings of this study can help for better understanding of the interaction between the asphaltenes and wax in wax deposition. 展开更多
关键词 ASPHALTENES Precipitation/aggregation existence state of asphaltenes Deposition
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