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1.
Heliyon ; 10(17): e36950, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39286145

RESUMEN

Because of their numerous benefits such as high charge cycle count, low self-discharge rate, low maintenance requirements, and tiny footprint, Li-batteries have been extensively employed in recent times. However, mostly Li-batteries have a limited lifespan of up to three years after production, may catch fire if the separator is damaged, and cannot be recharged when they are fully depleted. Due to the significant heat generation that li-batteries produce while they are operating, the temperature difference inside the battery module rises. This reduces the operating safety of battery and limits its life. Therefore, maintaining safe battery temperatures requires efficient thermal management using both active and passive. Thermal optimization may be achieved battery thermal management system (BTMS) that employs phase change materials (PCMs). However, PCM's shortcomings in secondary heat dissipation and restricted thermal conductivity still require development in the design, structure, and materials used in BTMS. We summarize new methods to control temperature of batteries using Nano-Enhanced Phase Change Materials (NEPCMs), air cooling, metallic fin intensification, and enhanced composite materials using nanoparticles which work well to boost their performance. To the scientific community, the idea of nano-enhancing PCMs is new and very appealing. Hybrid and ternary battery modules are already receiving attention for the li-battery life span enhancement ultimately facilitating their broader adoption across various applications, from portable electronics to electric vehicles and beyond.

3.
ACS Omega ; 9(10): 11081-11109, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38497021

RESUMEN

This comprehensive review analysis examines the domain of composite thermoelectric materials that integrate nanoparticles, providing a critical assessment of their methods for improving thermoelectric properties and the procedures used for their fabrication. This study examines several approaches to enhance power factor and lattice thermal conductivity, emphasizing the influence of secondary phases and structural alterations. This study investigates the impact of synthesis methods on the electrical characteristics of materials, with a particular focus on novel techniques such as electrodeposition onto carbon nanotubes. The acquired insights provide useful guidance for the creation of new thermoelectric materials. The review also compares and contrasts organic and inorganic thermoelectric materials, with a particular focus on the potential of inorganic materials in the context of waste heat recovery and power production within industries. This analysis highlights the role of inorganic materials in improving energy efficiency and promoting environmental sustainability.

4.
Sci Rep ; 12(1): 11658, 2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35804039

RESUMEN

The present study probed the creation of heat energy and concentrating into Newtonian liquids across vertical 3D-heated plates. The role of the Soret and Dufour theories in concentrating and energy formulas is discussed. The role of hybrid nanoparticles is introduced to illustrate particle efficiency in terms of solute and thermal energy. It is removed a viscous dissipation process and a changing magnetic field. The proposed approach is motivated by the need to maximize solute and thermal energy uses in biological and industrial domains. The constructed system of (partial differential equations) PDEs includes concentration, momentum, and thermal energy equations within various thermal characteristics. Transformations are used to formulate the system of (ordinary differential equations) ODEs for solution. To assess various features vs various variables, a Galerkin finite element approach is used. Motion into nanoscale components is shown to be smaller than motion into hybrid nanoparticles. Furthermore, fluctuations in heat energy and solute particle counts are seen in relation to changes in Soret, Eckert, magnetic, and Dufour numbers. The basic finding is that the generation of thermal energy for hybridized nanomaterials is much higher.

5.
Sci Rep ; 12(1): 12219, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35851297

RESUMEN

Fluid-structure interaction (FSI) gained a huge attention of scientists and researchers due to its applications in biomedical and mechanical engineering. One of the most important applications of FSI is to study the elastic wall behavior of stenotic arteries. Blood is the suspension of various cells characterized by shear thinning, yield stress, and viscoelastic qualities that can be assessed by using non-Newtonian models. In this study we explored non-Newtonian, incompressible Casson fluid flow in a bifurcated artery with a stenosis. The two-dimensional Casson model is used to study the hemodynamics of the flow. The walls of the artery are supposed to be elastic and the stenosis region is constructed in both walls. Suitable scales are used to transform the nonlinear differential equations into a dimensionless form. The problem is formulated and discretized using Arbitrary Lagrangian-Eulerian (ALE) approach. The finite element method (FEM) technique is used to solve the system of equations, together with appropriate boundary conditions. The analysis is carried out for the Bingham number, Hartmann number, and Reynolds number. The graphical results of pressure field, velocity profile, and load on the walls are assessed and used to study the influence of hemodynamic effects on stenotic arteries, bifurcation region, and elastic walls. This study shows that there is an increase in wall shear stresses (WSS) with increasing values of Bingham number and Hartmann number. Also, for different values of the Bingham number, the load on the upper wall is computed against the Hartmann number. The result indicate that load at the walls increases as the values of Bingham number and Hartmann number increase.


Asunto(s)
Hemodinámica , Modelos Cardiovasculares , Arterias , Velocidad del Flujo Sanguíneo , Simulación por Computador , Constricción Patológica , Humanos , Estrés Mecánico
6.
Materials (Basel) ; 15(2)2022 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-35057249

RESUMEN

In the current work, an investigation has been carried out for the Bingham fluid flow in a channel-driven cavity with a square obstacle installed near the inlet. A square cavity is placed in a channel to accomplish the desired results. The flow has been induced using a fully developed parabolic velocity at the inlet and Neumann condition at the outlet, with zero no-slip conditions given to the other boundaries. Three computational grids, C1, C2, and C3, are created by altering the position of an obstacle of square shape in the channel. Fundamental conservation and rheological law for viscoplastic Bingham fluids are enforced in mathematical modeling. Due to the complexity of the representative equations, an effective computing strategy based on the finite element approach is used. At an extra-fine level, a hybrid computational grid is created; a very refined level is used to obtain results with higher accuracy. The solution has been approximated using P2 - P1 elements based on the shape functions of the second and first-order polynomial polynomials. The parametric variables are ornamented against graphical trends. In addition, velocity, pressure plots, and line graphs have been provided for a better physical understanding of the situation Furthermore, the hydrodynamic benchmark quantities such as pressure drop, drag, and lift coefficients are assessed in a tabular manner around the external surface of the obstacle. The research predicts the effects of Bingham number (Bn) on the drag and lift coefficients on all three grids C1, C2, and C3, showing that the drag has lower values on the obstacle in the C2 grid compared with C1 and C3 for all values of Bn. Plug zone dominates in the channel downstream of the obstacle with augmentation in Bn, limiting the shear zone in the vicinity of the obstacle.

7.
Sci Rep ; 11(1): 23835, 2021 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-34903853

RESUMEN

Fluid structure interaction (FSI) gained attention of researchers and scientist due to its applications in science fields like biomedical engineering, mechanical engineering etc. One of the major application in FSI is to study elastic wall behavior of stenotic arteries. In this paper we discussed an incompressible Non-Newtonian blood flow analysis in an elastic bifurcated artery. A magnetic field is applied along [Formula: see text] direction. For coupling of the problem an Arbitrary Lagrangian-Eulerian formulation is used by two-way fluid structure interaction. To discretize the problem, we employed [Formula: see text] finite element technique to approximate the velocity, displacement and pressure and then linearized system of equations is solved using Newton iteration method. Analysis is carried out for power law index, Reynolds number and Hartmann number. Hemodynamic effects on elastic walls, stenotic artery and bifurcated region are evaluated by using velocity profile, pressure and loads on the walls. Study shows there is significant increase in wall shear stresses with an increase in Power law index and Hartmann number. While as expected increase in Reynolds number decreases the wall shear stresses. Also load on the upper wall is calculated against Hartmann number for different values of power law index. Results show load increases as the Hartmann number and power law index increases. From hemodynamic point of view, the load on the walls is minimum for shear thinning case but when power law index increased i.e. for shear thickening case load on the walls increased.


Asunto(s)
Arterias/fisiología , Circulación Sanguínea , Constricción Patológica/fisiopatología , Campos Magnéticos , Modelos Cardiovasculares , Animales , Elasticidad , Análisis de Elementos Finitos , Hemodinámica , Humanos , Hidrodinámica
9.
J Med Virol ; 88(5): 790-7, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26399724

RESUMEN

Suboptimal viral suppression and CD4 response to antiretroviral treatment (HAART) is known to cause poor outcomes with the increase cost of treatment. We aimed to assess factors associated with such control among HIV/AIDS patients in Malaysia. Four hundred and six HIV/AIDS patients, using Antiretroviral Therapy (ART) for at least the past three months, treated as outpatients at medication therapy adherence clinics (MTAC) were recruited. CD4 cell counts, viral load readings along with co-variants such as socio-demographic factors, adverse drug reactions, comorbidities, and medication record were obtained. Statistical Package for Social Sciences (SPSS(®)) version 18 and STATA IC(®) version 12 were used for data analysis. CD4 counts were found highest among those within the age category 41-50 years (390.43 ± 272.28), female (402.64 ± 276.14), other ethnicities (400.20 ± 278.04), and participants with no formal education (414.87 ± 290.90). Patients experiencing adverse effects had a 2.28 (95%CI:1.25-4.18) fold greater risk of poor CD4 control, while patients with comorbidities had 2.46 (95%CI:1.02-5.91) fold greater risk of mild viral suppression. Adverse drug reactions, co-morbidities were found to be significantly associated with poor immunological and virological outcomes in HIV/AIDS patients. However, a comprehensive evaluation is needed to better understand other confounders.


Asunto(s)
Antirretrovirales/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Carga Viral , Adolescente , Adulto , Anciano , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/epidemiología , Humanos , Malasia/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Insuficiencia del Tratamiento , Adulto Joven
10.
J Ayub Med Coll Abbottabad ; 22(1): 164-7, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21409934

RESUMEN

BACKGROUND: Preterm premature rupture of membranes is responsible for one third of all preterm births and is associated with significant maternal, foetal and neonatal risks. The objectives were to compare the foeto-maternal outcome in patient with and without preterm premature rupture of membranes. METHOD: This prospective comparative study was conducted in Gynae-C Unit of Ayub Teaching Hospital from Sep 2005 to Mar 2006. Total 170 cases were recruited in the study out of which 85 had Preterm Premature Rupture of Membranes (PPROM), and 85 had preterm labour without PROM. Patients' data were recorded on a performa. Maternal outcome was measured on the basis of presence of fever and mode of delivery. Foetal outcome was measured on the basis of weight of the baby, and presence of infection (fever), APGAR score and neonatal death. Analysis was performed using SPSS-10. RESULTS: The primary data arranged in groups was divided into PPROM and no-PPROM groups. The PPROM was found to be frequent in younger age group between 15-25 years while no-PPROM was common among the age group between 26-35 years (p = 0.002). Lower socioeconomic class and history of previous one or more preterm delivery was significantly associated with PPROM (p = 0.001). Maternal fever was also significant in the PPROM group (p = 0.01). Low birth weight was statistically significant in the PPROM group. Majority of the babies born to mother were either extremely low birth weight or low birth weight, i.e., between 1-25 kg (p = 0.005). Low APGAR score at the time of delivery (p = 0.01) and foetal infection (p = 0.002) between the PROM and no-PPROM group was found to be statistically significant Neo-natal deaths was also higher in the PPROM group as compared to no PPROM group (11 verses 2) (p = 0.009). CONCLUSION: In our study premature rupture of membrane had increased neonatal morbidity and mortality as compared to preterm birth. Strategies should be developed for its prevention.


Asunto(s)
Rotura Prematura de Membranas Fetales/diagnóstico , Rotura Prematura de Membranas Fetales/terapia , Resultado del Embarazo , Adolescente , Adulto , Femenino , Humanos , Recién Nacido , Persona de Mediana Edad , Embarazo , Estudios Prospectivos , Factores de Riesgo , Resultado del Tratamiento
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