The European Physical Journal Special Topics最新文献_第2页

Insight into the Hamilton and Crosser model for ternary hybrid nanofluid flow over a Riga wedge with heterogeneous catalytic reaction 汉密尔顿和克罗瑟三元混合纳米流体流过里加楔块与异质催化反应模型的深入研究

The European Physical Journal Special Topics Pub Date : 2024-09-16 DOI: 10.1140/epjs/s11734-024-01319-8

A. M. Obalalu, S. H. A. M. Shah, Adil Darvesh, Umair Khan, Anuar Ishak, Peter Adegbite, O. B. Ojewola, Taseer Muhammad, Ahmed M. Galal

{"title":"Insight into the Hamilton and Crosser model for ternary hybrid nanofluid flow over a Riga wedge with heterogeneous catalytic reaction","authors":"A. M. Obalalu, S. H. A. M. Shah, Adil Darvesh, Umair Khan, Anuar Ishak, Peter Adegbite, O. B. Ojewola, Taseer Muhammad, Ahmed M. Galal","doi":"10.1140/epjs/s11734-024-01319-8","DOIUrl":"https://doi.org/10.1140/epjs/s11734-024-01319-8","url":null,"abstract":"The present article is designed to study the Hamilton and Crosser model applied to the flow of ternary hybrid nanofluids over a Riga wedge, incorporating the effects of heterogeneous catalytic reactions. The complex interactions within the ternary hybrid nanofluids, comprising three distinct nanoparticles suspended in a base fluid, present significant challenges in accurately predicting flow and thermal characteristics. The Hamilton and Crosser model, known for its efficacy in determining the thermal conductivity of composite materials, is employed to analyze this intricate system. The analysis reveals the model's potential in offering a comprehensive understanding of the thermal and fluid dynamics involved, highlighting its suitability for predicting the behavior of ternary hybrid nanofluids in the presence of catalytic reactions. The governing model equations and boundary conditions are non-dimensionalized by introducing suitable similarity transformations. Thereafter, the computational Chebyshev collocation spectral technique implemented in the MATHEMATICA 11.3 software is used to calculate the numerical solution. The study reveals that the Casson parameter has a negative influence on the velocity distribution, causing it to reduce as the Casson parameter rises. This research contributes to the advancement of modeling techniques for complex fluid systems, with implications for enhanced design and optimization in various industrial and engineering applications.","PeriodicalId":501403,"journal":{"name":"The European Physical Journal Special Topics","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Iterative boundary element method for modeling an inverted T-type porous barrier in presence of ocean currents 为存在洋流的倒 T 型多孔屏障建模的迭代边界元法

The European Physical Journal Special Topics Pub Date : 2024-09-13 DOI: 10.1140/epjs/s11734-024-01327-8

Santanu Kumar Dash, Santanu Koley

引用次数: 0

Development of a centrifugal flow left ventricular assist device through hydrodynamic simulation and in vitro experimentation 通过流体力学模拟和体外实验开发离心流左心室辅助装置

The European Physical Journal Special Topics Pub Date : 2024-09-12 DOI: 10.1140/epjs/s11734-024-01315-y

Pulak Kumar Ray, Sumanta Laha, Arup Kumar Das, Prasanta Kumar Das

{"title":"Development of a centrifugal flow left ventricular assist device through hydrodynamic simulation and in vitro experimentation","authors":"Pulak Kumar Ray, Sumanta Laha, Arup Kumar Das, Prasanta Kumar Das","doi":"10.1140/epjs/s11734-024-01315-y","DOIUrl":"https://doi.org/10.1140/epjs/s11734-024-01315-y","url":null,"abstract":"Left ventricular assist devices (LVADs) have proven to be the best alternative treatment to address the increasing number of heart failures, while donors are in short supply. However, ventricular assist devices (VADs) have been linked to thrombosis, hemolysis, and other postoperative complications. Despite significant technological advancements, blood damage caused by high shear stress generation has remained a serious concern, which is greatly attributed to the VAD's geometry. The goal of this research is to develop a centrifugal pump design using computational fluid dynamics (CFD) and experimental evaluation. Based on characteristics such as pressure head generation, flow rate, maximum wall shear stress, and hydraulic efficiency, the simulations produce a pump design suitable for mechanical circulatory support. The subsequent experimental testing for pressure head and flow rates validate the CFD outcomes. Further, the pump is installed in an indigenously designed mock circulation loop to examine its capability as an LVAD. The outcomes of CFD and experimental studies reveal that the developed pump is well capable of delivering blood with a flow rate at the required pressure as per desired physiological requirements. Also, the wall shear stress values are within the limit (< 300 N/m2) to avoid any blood damage.","PeriodicalId":501403,"journal":{"name":"The European Physical Journal Special Topics","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Noise-induced destruction of equilibrium regimes and spiking patterns formation in calcium dynamics 噪声诱导的钙动力学平衡状态破坏和尖峰模式形成

The European Physical Journal Special Topics Pub Date : 2024-09-12 DOI: 10.1140/epjs/s11734-024-01310-3

Irina Bashkirtseva, Stepan Kachusov, Lev Ryashko

引用次数: 0

An investigation of the Nernst–Planck model of an electro-viscous fluid flow between squeezing plates with homogeneous–heterogeneous reactions 对挤压板间具有同质异相反应的电粘性流体流动的 Nernst-Planck 模型的研究

The European Physical Journal Special Topics Pub Date : 2024-09-11 DOI: 10.1140/epjs/s11734-024-01314-z

Wajid Ullah Jan, Muhammad Farooq, Rehan Ali Shah, Aamir Khan, Rashid Jan, Yasser Alrashedi

{"title":"An investigation of the Nernst–Planck model of an electro-viscous fluid flow between squeezing plates with homogeneous–heterogeneous reactions","authors":"Wajid Ullah Jan, Muhammad Farooq, Rehan Ali Shah, Aamir Khan, Rashid Jan, Yasser Alrashedi","doi":"10.1140/epjs/s11734-024-01314-z","DOIUrl":"https://doi.org/10.1140/epjs/s11734-024-01314-z","url":null,"abstract":"The significant influence of convective transport flow between compressing plates involving both homogeneous and heterogeneous reactions, with uniform ionic distribution across the plates’ surfaces, is examined. The physical situation is elucidated through the utilization of fundamental equations governing fluid flow, including the Poisson–Boltzmann equation, the energy equation, and the Nernst–Planck equation, as well as equations pertaining to heterogeneous and homogeneous reactions. The governing equations undergo a transformation into systems of ODEs through a similarity transformation. These equations are then solved numerically utilizing the BVP4c technique for different controlling parameter values, and the outcomes are tabulated and visually represented. In addition, a homotopy analysis method (HAM) is employed to solve the resulting equations. The accuracy and validity of the HAM findings are confirmed by comparing them to solutions obtained from BVP4c numerical solver packages. Based on both homogeneous and heterogeneous chemical reactions, it is concluded that compressing plates increases the distribution of anions and cations. Physical restrictions impact vertical and horizontal velocities, as well as positive and negative charge profiles, are drawn and briefly described. Furthermore, the rate of vertical velocity near the parallel plates increases with an increase in the squeezing Reynolds number.","PeriodicalId":501403,"journal":{"name":"The European Physical Journal Special Topics","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Foundations of automatic feature extraction at LHC–point clouds and graphs 大型强子对撞机自动特征提取的基础--点云和图形

The European Physical Journal Special Topics Pub Date : 2024-09-11 DOI: 10.1140/epjs/s11734-024-01306-z

Akanksha Bhardwaj, Partha Konar, Vishal Ngairangbam

引用次数: 0

Directional crystallization of a two-phase region with a mixed conductive–convective heat and mass transport 双相区的定向结晶与传导-对流混合热量和质量传输

The European Physical Journal Special Topics Pub Date : 2024-09-11 DOI: 10.1140/epjs/s11734-024-01309-w

Eugenya V. Makoveeva, Dmitri V. Alexandrov

{"title":"Directional crystallization of a two-phase region with a mixed conductive–convective heat and mass transport","authors":"Eugenya V. Makoveeva, Dmitri V. Alexandrov","doi":"10.1140/epjs/s11734-024-01309-w","DOIUrl":"https://doi.org/10.1140/epjs/s11734-024-01309-w","url":null,"abstract":"Here we consider the influence of simultaneous operation of convective and conductive heat and mass fluxes in a binary liquid on directional crystallization processes with a two-phase region. We consider two possible crystallization scenarios with constant and unsteady growth velocities and construct the corresponding analytical solutions in a parametric form. These solutions enable us to find such process characteristics as temperature, impurity concentration, solid-phase fraction, the laws of motion for the two-phase region boundaries dependent on material parameters and crystallization driving force, i.e. the specified system cooling conditions. The solutions obtained enable us to describe the material microstructure by means of two-phase region permeability and primary interdendritic spacing dependent on the solid-phase fraction of a solidified material. The theory under consideration also enables us to find the unfrozen liquid phase fraction of a two-phase material released in ice and permafrost melting processes, which defines the biophysical significance of the issue under study.","PeriodicalId":501403,"journal":{"name":"The European Physical Journal Special Topics","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Network analysis of the relationship between different heart rate variability metrics during sleep 睡眠期间不同心率变异性指标之间关系的网络分析

The European Physical Journal Special Topics Pub Date : 2024-09-10 DOI: 10.1140/epjs/s11734-024-01318-9

Erik Leonardo Mateos-Salgado, José Esael Pineda-Sánchez, Fructuoso Ayala-Guerrero, Carlos Alberto Gutiérrez-Chávez

{"title":"Network analysis of the relationship between different heart rate variability metrics during sleep","authors":"Erik Leonardo Mateos-Salgado, José Esael Pineda-Sánchez, Fructuoso Ayala-Guerrero, Carlos Alberto Gutiérrez-Chávez","doi":"10.1140/epjs/s11734-024-01318-9","DOIUrl":"https://doi.org/10.1140/epjs/s11734-024-01318-9","url":null,"abstract":"Heart rate variability (HRV) refers to the physiological phenomenon of variation in heartbeat duration, which can be characterized using various metrics. Considering a complex systems approach, in this study we used network modeling to quantitatively evaluate the relationship between different HRV metrics during sleep. Polysomnography recordings were performed on 24 healthy participants and their cardiac activity was sampled from the N2, N3, and REM sleep stages. Fifty-eight HRV metrics were calculated, and the relationship between each was assessed using mutual information (MI). One network was created for each sleep stage; HRV metrics constituted its nodes, and MI values were used to establish its edges. Repeated measures ANOVA was applied to each metric to assess variation between sleep stages. It was found that all three networks had characteristics of complex networks. Several communities of shared similar metrics were found across the three sleep stages. Of these, one community had the same metrics in stages N2 and N3, but in REM sleep was divided into three communities. REM sleep exhibited significant differences compared to the other sleep stages in several metrics. These preliminary findings allow us to suggest the application of this method in other HRV research contexts, which will determine its scope and limitations.","PeriodicalId":501403,"journal":{"name":"The European Physical Journal Special Topics","volume":"303 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigating the quality measures of image enhancement by convoluting the coefficients of analytic functions 通过卷积解析函数系数研究图像增强的质量测量方法

The European Physical Journal Special Topics Pub Date : 2024-09-09 DOI: 10.1140/epjs/s11734-024-01317-w

B. Nandhini, B. Sruthakeerthi

引用次数: 0

Acute lymphoblastic leukemia classification using persistent homology 利用持续同源性对急性淋巴细胞白血病进行分类

The European Physical Journal Special Topics Pub Date : 2024-09-06 DOI: 10.1140/epjs/s11734-024-01301-4

Waqar Hussain Shah, Abdullah Baloch, Rider Jaimes-Reátegui, Sohail Iqbal, Syeda Rafia Fatima, Alexander N. Pisarchik

引用次数: 0