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1.
Nanoscale Adv ; 5(23): 6560-6571, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38024313

RESUMO

Nanotechnology has gained substantial attention on account of its vast applications in food manufacturing, heat exchanges, electronic cooling systems, medical treatment, coolant processes, energy production, biotechnology, transportation, biochemistry, nuclear reactors, and metrology. Currently, the phenomenon of bioconvection using nanomaterials has found wide industrial and technical implementations. Contemporary nanofluids are a dynamic source for illuminating heat transport systems related to engineering as well as industrial phenomena. Bioconvection has numerous applications in bio-micro-systems, owing to the augmentation in mass renovation besides collaborating, which are vital complications in diverse micro-systems. This study intended to model and examine an incompressible, unsteady 3D Casson fluid nanofluid with bioconvection on a stretching surface. A model by means of these characteristics is beneficial in applications, such as in nuclear reactors, coolants in automobiles, metallurgical procedures, energy construction, micro-manufacturing, industrial engineering, and geophysical fluid mechanics along with dynamics. The performance of the Brownian motion along with thermophoresis diffusion is assumed through an extraordinary effect of thermal radiation in the temperature equation of the fluid movement. This model was created by using PDE, which was then converted into an ODE system. The somatic behavior of substantial parameters was investigated graphically. Similarly, tables were interpreted to display the effect of the control of physical quantities on the local Nusselt number, local Sherwood number, and motile density. Consequently, it was determined that the temperature of Casson fluid grew exponentially with higher estimates of the magnetic parameter and the thermal Biot number. At the same time, we detected that augmented estimation of the Lewis number decreases the Casson fluid concentration. For growing values of the parameters, Biot number and the stretching parameter, there is a direct reaction for the microorganism profile.

2.
Environ Res ; 237(Pt 1): 116943, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37619627

RESUMO

The current study analyzed the high heating values (HHVs) of various waste biomass materials intending to the effective management and more sustainable consumption of waste as clean energy source. Various biomass waste samples including date leaves, date branches, coconut leaves, grass, cooked macaroni, salad, fruit and vegetable peels, vegetable scraps, cooked food waste, paper waste, tea waste, and cardboard were characterized for proximate analysis. The results revealed that all the waste biomass were rich in organic matter (OM). The total OM for all waste biomass ranged from 79.39% to 98.17%. Likewise, the results showed that all the waste biomass resulted in lower ash content and high fixed carbon content associated with high fuel quality. Based on proximate analysis, various empirical equations (HHV=28.296-0.2887(A)-656.2/VM, HHV=18.297-0.4128(A)+35.8/FC and HHV=22.3418-0.1136(FC)-0.3983(A)) have been tested to predict HHVs. It was observed that the heterogeneous nature of various biomass waste considerably affects the HHVs and hence has different fuel characteristics. Similarly, the HHVs of waste biomass were also determined experimentally using the bomb calorimeter, and it was observed that among all the selected waste biomass, the highest HHVs (21.19 MJ kg-1) resulted in cooked food waste followed by cooked macaroni (20.25 MJ kg-1). The comparison revealed that experimental HHVs for the selected waste biomass were slightly deviated from the predicted HHVs. Based on HHVs, various thermochemical and biochemical technologies were critically overviewed to assess the suitability of waste biomass to energy products. It has been emphasized that valorizing waste-to-energy technologies provides the dual benefits of sustainable management and production of cleaner energy to reduce fossil fuels dependency. However, the key bottleneck in commercializing waste-to-energy systems requires proper waste collection, sorting, and continuous feedstock supply. Moreover, related stakeholders should be involved in designing and executing the decision-making process to facilitate the global recognition of waste biorefinery concept.

3.
AJNR Am J Neuroradiol ; 43(11): 1615-1620, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36229166

RESUMO

BACKGROUND AND PURPOSE: Flow diversion has gradually become a standard treatment for intracranial aneurysms of the anterior circulation. Recently, the off-label use of the flow diverters to treat posterior circulation aneurysms has also increased despite initial concerns of rupture and the suboptimal results. This study aimed to explore the change in complication rates and treatment outcomes across time for posterior circulation aneurysms treated using flow diversion and to further evaluate the mechanisms and variables that could potentially explain the change and outcomes. MATERIALS AND METHODS: A retrospective review using a standardized data set at multiple international academic institutions was performed to identify patients with ruptured and unruptured posterior circulation aneurysms treated with flow diversion during a decade spanning January 2011 to January 2020. This period was then categorized into 4 intervals. RESULTS: A total of 378 procedures were performed during the study period. Across time, there was an increasing tendency to treat more vertebral artery and fewer large vertebrobasilar aneurysms (P = .05). Moreover, interventionalists have been increasingly using fewer overlapping flow diverters per aneurysm (P = .07). There was a trend toward a decrease in the rate of thromboembolic complications from 15.8% in 2011-13 to 8.9% in 2018-19 (P = .34). CONCLUSIONS: This multicenter experience revealed a trend toward treating fewer basilar aneurysms, smaller aneurysms, and increased usage of a single flow diverter, leading to a decrease in the rate of thromboembolic and hemorrhagic complications.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Procedimentos Endovasculares/métodos , Curva de Aprendizado , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Resultado do Tratamento , Estudos de Coortes , Estudos Retrospectivos , Embolização Terapêutica/métodos , Stents
4.
Micromachines (Basel) ; 13(9)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36144038

RESUMO

Curved veins and arteries make up the human cardiovascular system, and the peristalsis process underlies the blood flowing in these ducts. The blood flow in the presence of hybrid nanoparticles through a tapered complex wavy curved channel is numerically investigated. The behavior of the blood is characterized by the Casson fluid model while the physical properties of iron (Fe3O4) and copper (Cu) are used in the analysis. The fundamental laws of mass, momentum and energy give rise the system of nonlinear coupled partial differential equations which are normalized using the variables, and the resulting set of governing relations are simplified in view of a smaller Reynolds model approach. The numerical simulations are performed using the computational software Mathematica's built-in ND scheme. It is noted that the velocity of the blood is abated by the nanoparticles' concentration and assisted in the non-uniform channel core. Furthermore, the nanoparticles' volume fraction and the dimensionless curvature of the channel reduce the temperature profile.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35463478

RESUMO

In the present study, design of intelligent numerical computing through backpropagated neural networks (BNNs) is presented for numerical treatment of the fluid mechanics problems governing the dynamics of magnetohydrodynamic fluidic model (MHD-NFM) past a stretching surface embedded in porous medium along with imposed heat source/sink and variable viscosity. The original system model MHD-NFM in terms of PDEs is converted to nonlinear ODEs by introducing the similarity transformations. A reference dataset for BNNs approach is generated with Adams numerical solver for different scenarios of MHD-NFM by variation of parameter of viscosity, parameter of heat source and sink, parameter of permeability, magnetic field parameter, and Prandtl number. To calculate the approximate solution for MHD-NFM for different scenarios, the training, testing, and validation processes are conducted in parallel to adapt neural networks by reducing the mean square error (MSE) function through Levenberg-Marquardt backpropagation. The comparative studies and performance analyses through outcomes of MSE, error histograms, correlation and regression demonstrate the effectiveness of proposed BNNs methodology.

7.
Sci Rep ; 11(1): 20252, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642381

RESUMO

The transverse momentum spectra of light nuclei (deuteron, triton and helion) produced in various centrality intervals in Gold-Gold (Au-Au), Lead-Lead (Pb-Pb) and proton-Lead (p-Pb) collisions, as well as in inelastic (INEL) proton-proton (p-p) collisions are analyzed by the blast wave model with Boltzmann Gibbs statistics. The model results are nearly in agreement with the experimental data measured by STAR and ALICE Collaborations in special transverse momentum ranges. We extracted the bulk properties in terms of kinetic freezeout temperature, transverse flow velocity and freezeout volume. It is observed that deuteron and anti-deuteron freezeout later than triton and helion as well as their anti-particles due to its smaller mass, while helion and triton, and anti-helion and anti-triton freezeout at the same time due to isospin symmetry at higher energies. It is also observed that light nuclei freezeout earlier than their anti-nuclei due to the large coalescence of nucleons for light nuclei compared to their anti-nuclei. The kinetic freezeout temperature, transverse flow velocity and kinetic freezeout volume decrease from central to peripheral collisions. Furthermore, the transverse flow velocity depends on mass of the particle which decreases with increasing the mass of the particle.

8.
Braz. j. biol ; 81(1): 98-104, Feb. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153320

RESUMO

Abstract Fish is consumed as a rich and cheaper source of white meat and proteins all over the world. Fish farming is the leading source of income generation throughout the world. The present research study was conducted with aims to investigate the ecto and endo parasitic fauna of S. plagiostomus (snow trout) in River Swat. A total of 96 fish samples were collected on monthly basis from July-2018 to February-2019, from upper, middle and lower reaches. Fish samples were collected with the help of cast net, hand net and fishing rods. Local fishermen and experts help were also sought out for fish collection. 61 out of 96 fishes were found infected by helminth parasites. The total prevalence and intensity of 63.54% and 2.90 was observed respectively during data analysis. Highest monthly prevalence of 83.33% was recorded during July and August, while lowest prevalence of 33.33% was noted during February. Five species of helminths parasites were detected from S. plagiostomus, of which two were trematodes (Rhabdochona shizothoracis and Rhabdochona species), one species of Monogenia (Diplozoon paraddoxum), one species of Cestodes (Nippotaenia species), and one species of Acanthocephalan (Neoechynorhynchus devdevi). Highest parasite wise prevalence, intensity and relative density of 21.87%, 4.09 and 0.895 was noted for R. schizothoracis while the lowest prevalence, intensity and relative density of 4.16%, 1.25 and 0.052 was noted for N. devdevi. Highest infection of 76.08% was observed in adults host while lowest, 40% infestation rate was observed in young fish samples. 73.68% prevalence was observed in female hosts while only 56.90% prevalence was observed in male individuals. Higher infection (83.33%) was noticed during summer season, while lowest infection (44.44%) was observed during winter season. Similarly 71.79% fishes were found infected that were collected from lower reaches of the River Swat than the fish samples collected from upper reaches (52%).


Resumo O peixe é consumido mundialmente por ser uma fonte rica e barata de carne branca e proteínas. A piscicultura é a principal fonte de geração de renda em todo o mundo. O presente estudo foi conduzido com o objetivo de investigar a fauna ecto e endoparasitária de S. plagiostomus (truta da neve) no rio Swat. Foram coletadas mensalmente 96 amostras de peixes, no período de julho de 2018 a fevereiro de 2019, nos trechos alto, médio e baixo com auxílio de redes de arrasto, redes de mão e varas de pesca. Pescadores locais e especialistas também ajudaram na coleta de peixes. Dos 96 peixes encontrados, 61 estavam infectados por parasitas helmintos. A prevalência de 63,54% e a intensidade total de 2,90 foram observadas durante a análise dos dados. A maior prevalência mensal de 83,33% foi registrada nos meses de julho e agosto, enquanto a menor, de 33,33%, em fevereiro. Cinco espécies de parasitas helmintos foram detectadas de S. plagiostomus, dos quais dois eram trematódeos (espécies Rhabdochona shizothoracis e Rhabdochona), uma espécie de monogenia (Diplozoon paradoxum), uma espécie de cestóideos (espécie Nippotaenia) e uma espécie de acantocéfalo (Neoechynorhynchus devdevi). As maiores prevalências de parasitas (21,87%), intensidade (4,09) e densidade relativa (0,895) foram observadas em R. schizothoracis, enquanto as menores prevalências de parasitas (4,16%), intensidade (1,25) e densidade relativa (0,052), em N. devdevi. A infecção mais alta (76,08%) foi constatada em adultos hospedeiros, ao passo que a taxa de infestação mais baixa (40%) foi encontrada em amostras de peixes jovens. A prevalência de 73,68% foi verificada em hospedeiros do sexo feminino, enquanto a de 56,90%, em indivíduos do sexo masculino. Maior infecção (83,33%) foi observada durante a temporada de verão, e a menor infecção (44,44%), durante o inverno. Da mesma forma, 71,79% dos peixes encontrados infectados foram coletados no trecho baixo do rio Swat, enquanto 52%, no trecho alto.


Assuntos
Humanos , Animais , Masculino , Feminino , Parasitos , Cyprinidae , Doenças dos Peixes/epidemiologia , Helmintos , Paquistão/epidemiologia , Rios , Peixes
9.
Braz J Biol ; 81(1): 98-104, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32578670

RESUMO

Fish is consumed as a rich and cheaper source of white meat and proteins all over the world. Fish farming is the leading source of income generation throughout the world. The present research study was conducted with aims to investigate the ecto and endo parasitic fauna of S. plagiostomus (snow trout) in River Swat. A total of 96 fish samples were collected on monthly basis from July-2018 to February-2019, from upper, middle and lower reaches. Fish samples were collected with the help of cast net, hand net and fishing rods. Local fishermen and experts help were also sought out for fish collection. 61 out of 96 fishes were found infected by helminth parasites. The total prevalence and intensity of 63.54% and 2.90 was observed respectively during data analysis. Highest monthly prevalence of 83.33% was recorded during July and August, while lowest prevalence of 33.33% was noted during February. Five species of helminths parasites were detected from S. plagiostomus, of which two were trematodes (Rhabdochona shizothoracis and Rhabdochona species), one species of Monogenia (Diplozoon paraddoxum), one species of Cestodes (Nippotaenia species), and one species of Acanthocephalan (Neoechynorhynchus devdevi). Highest parasite wise prevalence, intensity and relative density of 21.87%, 4.09 and 0.895 was noted for R. schizothoracis while the lowest prevalence, intensity and relative density of 4.16%, 1.25 and 0.052 was noted for N. devdevi. Highest infection of 76.08% was observed in adults host while lowest, 40% infestation rate was observed in young fish samples. 73.68% prevalence was observed in female hosts while only 56.90% prevalence was observed in male individuals. Higher infection (83.33%) was noticed during summer season, while lowest infection (44.44%) was observed during winter season. Similarly 71.79% fishes were found infected that were collected from lower reaches of the River Swat than the fish samples collected from upper reaches (52%).


Assuntos
Cyprinidae , Doenças dos Peixes , Helmintos , Parasitos , Animais , Feminino , Doenças dos Peixes/epidemiologia , Peixes , Humanos , Masculino , Paquistão/epidemiologia , Rios
10.
AJNR Am J Neuroradiol ; 42(1): 57-64, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33243895

RESUMO

BACKGROUND AND PURPOSE: Clot perviousness in acute ischemic stroke is a potential CT imaging biomarker for mechanical thrombectomy efficacy. We investigated the association among perviousness, clot cellular composition, and first-pass effect. MATERIALS AND METHODS: In 40 mechanical thrombectomy-treated cases of acute ischemic stroke, we calculated perviousness as the difference in clot density on CT angiography and noncontrast CT. We assessed the proportion of fibrin/platelet aggregates, red blood cells, and white blood cells on clot histopathology. We tested for linear correlation between histologic components and perviousness, differences in components between "high" and "low" pervious clots defined by median perviousness, and differences in perviousness/composition between cases that did and did not achieve a first-pass effect. RESULTS: Perviousness significantly positively and negatively correlated with the percentage of fibrin/platelet aggregates (P = .001) and the percentage of red blood cells (P = .001), respectively. Higher pervious clots had significantly greater fibrin/platelet aggregate content (P = .042). Cases that achieved a first-pass effect (n = 14) had lower perviousness, though not significantly (P = .055). The percentage of red blood cells was significantly higher (P = .028) and the percentage of fibrin/platelet aggregates was significantly lower (P = .016) in cases with a first-pass effect. There was no association between clot density on NCCT and clot composition or first-pass effect. Receiver operating characteristic analysis indicated that clot composition was the best predictor of first-pass effect (area under receiver operating characteristic curve: percentage of fibrin/platelet aggregates = 0.731, percentage of red blood cells = 0.706, perviousness = 0.668). CONCLUSIONS: Clot perviousness on CT is associated with a higher percentage of fibrin/platelet aggregate content. Histologic data and, to a lesser degree, perviousness may have value in predicting first-pass outcome. Imaging metrics that more strongly reflect clot biology than perviousness may be needed to predict a first-pass effect with high accuracy.


Assuntos
AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Trombose/diagnóstico por imagem , Resultado do Tratamento , Idoso , Plaquetas/patologia , Angiografia por Tomografia Computadorizada/métodos , Feminino , Fibrina/análise , Humanos , AVC Isquêmico/patologia , Masculino , Trombectomia/métodos , Trombose/patologia
11.
Comput Methods Programs Biomed ; 196: 105474, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32659644

RESUMO

Chilling systems are important in the improved technological thermal mechanisms which are considered continuously in passive along with active heat-transference improvement procedures. Engineers recommended several approaches to upsurge heat transference of thermal structures. The pulsating flow, corrugated tube, magnetic field aspect and nanoliquids are the heat-transference improvement procedures delved continuously. In present research work, we addressed the heat-transference characteristics of non-Newtonian (Oldroyd-B) liquid towards heated stratified surface. Thermally radiative laminar flow is modeled. In addition, we accounted Buongiorno's nanoliquid model which includes Brownian along with thermophoretic diffusions. Modeling is further based on heat source, magnetohydrodynamics, dual stratification, thermal radiation and convective conditions. Mathematical system is simplified through boundary-layer idea. Similarity variables are reported with the aim to simplify complex mathematical system. Homotopy algorithm yields convergent results of non-dimensional expressions. Our study unveils diminution of thermal along with solutal fields when stratification factors are increased.


Assuntos
Hidrodinâmica , Aves Canoras , Algoritmos , Animais , Difusão , Campos Magnéticos
12.
Comput Methods Programs Biomed ; 191: 105396, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32160577

RESUMO

Objective A recent evolution in fluid dynamics has been the consideration of nanoliquids which retains exceptional thermal conductivity characteristics and upsurge heat transportation in fluids. Inspired by this, the current attempt develops a nonlinear mathematical model (Williamson fluid) towards moving surface heated convectively. Formulated problem further encompasses thermophoresis, magnetic dipole, heat source, Brownian diffusion, thermal radiation and thermo-solutal convective conditions. Upshots are simulated and unveiled graphically. Drag force along with heat/mass transportation rates is addressed numerically. Method The dimensionless expressions are highly non-linear and exact/analytic computations for such expressions are not possible. Thus we employed numeric (bvp4c) scheme for solution development. Conclusions Temperature of Williamson nanofluid intesifies through larger Nb (Brownian movement) factor and Nt (thermophoretic variable). Moreover, Buongiorno relation has reverse behavior for concentration ϕ(η) of Williamson nanofluid regarding Nt and Nt. Transportation rate of heat dwindles against both Nt and Nb.


Assuntos
Hidrodinâmica , Modelos Estatísticos , Nanotecnologia , Condutividade Térmica , Algoritmos , Entropia , Fenômenos Magnéticos
13.
Eur J Neurol ; 27(6): 1039-1047, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32149450

RESUMO

BACKGROUND AND PURPOSE: We investigated the effectiveness of intravenous thrombolysis (IVT) in acute ischaemic stroke (AIS) patients with large vessel or distal occlusions and mild neurological deficits, defined as National Institutes of Health Stroke Scale scores < 6 points. METHODS: The primary efficacy outcome was 3-month functional independence (FI) [modified Rankin Scale (mRS) scores 0-2] that was compared between patients with and without IVT treatment. Other efficacy outcomes of interest included 3-month favorable functional outcome (mRS scores 0-1) and mRS score distribution at discharge and at 3 months. The safety outcomes comprised all-cause 3-month mortality, symptomatic intracranial hemorrhage (ICH), asymptomatic ICH and severe systemic bleeding. RESULTS: We evaluated 336 AIS patients with large vessel or distal occlusions and mild stroke severity (mean age 63 ± 15 years, 45% women). Patients treated with IVT (n = 162) had higher FI (85.6% vs. 74.8%, P = 0.027) with lower mRS scores at hospital discharge (P = 0.034) compared with the remaining patients. No differences were detected in any of the safety outcomes including symptomatic ICH, asymptomatic ICH, severe systemic bleeding and 3-month mortality. IVT was associated with higher likelihood of 3-month FI [odds ratio (OR), 2.19; 95% confidence intervals (CI), 1.09-4.42], 3-month favorable functional outcome (OR, 1.99; 95% CI, 1.10-3.57), functional improvement at discharge [common OR (per 1-point decrease in mRS score), 2.94; 95% CI, 1.67-5.26)] and at 3 months (common OR, 1.72; 95% CI, 1.06-2.86) on multivariable logistic regression models adjusting for potential confounders, including mechanical thrombectomy. CONCLUSIONS: Intravenous thrombolysis is independently associated with higher odds of improved discharge and 3-month functional outcomes in AIS patients with large vessel or distal occlusions and mild stroke severity. IVT appears not to increase the risk of systemic or symptomatic intracranial bleeding.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Administração Intravenosa , Idoso , Isquemia Encefálica/tratamento farmacológico , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Hemorragias Intracranianas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Trombectomia , Terapia Trombolítica , Resultado do Tratamento
14.
Dysphagia ; 35(6): 898-906, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32048021

RESUMO

The Ultrasound Velocity Profiling (UVP) technique allows real-time, non-invasive flow mapping of a fluid along a 1D-measuring line. This study explores the possibility of using the UVP technique and X-ray video-fluoroscopy (XVF) to elucidate the deglutition process with the focus on bolus rheology. By positioning the UVP probe so that the pulsed ultrasonic beam passes behind the air-filled trachea, the bolus flow in the pharynx can be measured. Healthy subjects in a clinical study swallowed fluids with different rheological properties: Newtonian (constant shear viscosity and non-elastic); Boger (constant shear viscosity and elastic); and shear thinning (shear rate-dependent shear viscosity and elastic). The results from both the UVP and XVF reveal higher velocities for the shear thinning fluid, followed by the Boger and the Newtonian fluids, demonstrating that the UVP method has equivalent sensitivities for detecting the velocities of fluids with different rheological properties. The velocity of the contraction wave that clears the pharynx was measured in the UVP and found to be independent of bolus rheology. The results show that UVP not only assesses accurately the fluid velocity in a bolus flow, but it can also monitor the structural changes that take place in response to a bolus flow, with the added advantage of being a completely non-invasive technique that does not require the introduction of contrast media.


Assuntos
Deglutição , Faringe , Cinerradiografia , Humanos , Faringe/diagnóstico por imagem , Reologia , Ondas Ultrassônicas , Viscosidade , Raios X
15.
Comput Methods Programs Biomed ; 190: 105347, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32062089

RESUMO

BACKGROUND AND OBJECTIVE: The scrutiny of nonlinear convected flow aspect has continuously appealed researchers attention because of its ample demands in processes like heat exchangers, building insulation, crystal growth, insulation of nuclear reactor, food processing, solar energy and electronic element chilling etc. Taking into consideration the aforesaid utilizations, we modeled differential type (second-grade) nanoliquid considering non-linear mixed convection. The considered differential type nonlinear model elaborates viscoelasticity (elastic and viscous) characteristics. Furthermore the thermal systems emphases on transportation of heat and irreversibility reduction. Especially, evaluating the systems via thermodynamic second relation is essential with the purpose of finding a standard communication between power input prerequisite and heat transference augmentation. METHOD: Formulated non-dimensional problem is non-linear subject to the assumptions (i.e., Non-linear mixed convection, magnetic field, viscous dissipation, double stratification, Joule heating and convective conditions). Analytic simulations for modeled non-linear systems is not possible. Hence we considered bvp4c scheme for non-linear analysis. CONCLUSIONS: Velocity [Formula: see text] of second grade (non-Newtonian) fluid intensifies for larger estimations of R* and λ* whereas it dwindles for M. Temperature of nanoliquid deteriorates with S1 while (θ(η)) rises against Ec. Entropy generation (EG) and (BN) (Bejan number) significantly affected by physical parameters M, α2 and Br.


Assuntos
Entropia , Campos Magnéticos , Nanoestruturas , Termodinâmica , Algoritmos , Animais , Convecção , Modelos Estatísticos
16.
Comput Methods Programs Biomed ; 190: 105363, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32062091

RESUMO

Background In this research communication, entropy optimized Darcy-Forchheimer flow with magnetohydrodynamic over a stretched surface is considered. Here Molybdenum disulfide (MOS2) and Silicon dioxide (SiO2) are taken as a nanoparticles and Propylene glycol as a continuous phase liquid. Electrically conducting fluid is considered and flow is generated via stretched surface of sheet. The total entropy rate which is depends on four types of irreversibilities i.e., heat transfer, porosity, fluid friction and dissipation) is calculated via second law of thermodynamics. The energy expression is mathematically modeled and discussed subject to heat generation/absorption, dissipation, thermal radiation and Joule heating. Furthermore, temperature dependent viscosity is accounted. Method The nonlinear PDE's (partial differential equations) are first changed to ODE's (ordinary differential equations) through implementation of appropriate similarity variables (transformations). The numerical results of ordinary ones are computed via Built-In-Shooting method. The results for the flow field, temperature, skin friction, Nusselt number and entropy generation are discussed against various sundry flow parameters graphically. Results Salient characteristics of sundry flow parameters on the entropy generation rate, velocity, Bejan number, gradients of velocity, gradient of temperature and temperature are examined and display graphically. The results are computed for both nanoparticles. From obtained results it is observed that temperature field increases versus higher thermal Biot number for both nanoparticles. It is also observed that the thermal field is more in presence of Molybdenum disulfide as compared to Silicon dioxide, because the thermal conductivity of Molybdenum disulfide is higher than Silicon dioxide. Entropy generation and Bejan number show contrast impact versus higher estimations of Brinkman number versus both nanoparticles.


Assuntos
Dissulfetos , Entropia , Hidrodinâmica , Molibdênio , Nanoestruturas , Dióxido de Silício , Algoritmos , Simulação por Computador , Convecção , Viscosidade
17.
Comput Methods Programs Biomed ; 190: 105252, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32059157

RESUMO

In this published paper, a mathematical modeling has been conducted for the peristaltic transport in flow of hybrid nanofluid between rotating channel in the presence of nonlinear thermal radiation, slip effects and entropy generation. This corrigendum correct the flow geometry, figures captions and plots "Transport of hybrid type nanomaterials in peristaltic activity of viscous fluid considering nonlinear radiation, entropy optimization and slip effects" [Computer Methods and Programs in Biomedicine 184 (2020) 105,086] where these mistake are occurred during production process and therefore, some captions are shuffled. The difference in the captions and plots however does not affect the authenticity and mathematical validity of the problem in purpose of this published research article is to investigate the peristaltic transport in flow of hybrid nanofluid between rotating channel subject to nonlinear thermal radiation, slip effects and entropy generation. However, the flow geometry and the captions and plots should be arranged.


Assuntos
Algoritmos , Hidrodinâmica , Nanoestruturas , Gráficos por Computador , Entropia , Viscosidade
18.
Comput Methods Programs Biomed ; 189: 105324, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32058126

RESUMO

BACKGROUND: Hybrid nanoliquids have several benefits in comparison to orthodox type liquids because of their revised attributes. The enhanced rheological along with thermo-physical attributes, create them additionally apposite for systems featuring solar energy. Thus, in the current analysis, the focus retained to pursue the diversity behave by hybrid nanofluid in comparison with traditional nanofluid considering the scheme of micropolar fluid in the environment of MHD, with rotating porous channel on the exponentially stretched surface. METHODS: For the solution of the generated differential model, a numerical technique BVP-4C is applied. The information extraction is done by the graphical representations of these solutions. RESULTS: The velocity, temperature, and micro-rotation are analyzed deeply under graphical representation. For nanofluid and hybrid nanofluid, we investigated a comprehensive behavior by the variation of skin friction and Nusselt number. As a result of these explorations, we found in depth the higher rate of heat transferring in the scenario of hybrid nanofluid in comparison with nanofluid in the manifestation of porosity and rotation.


Assuntos
Algoritmos , Temperatura Alta , Hidrodinâmica , Magnetismo , Modelos Teóricos , Nanotecnologia , Gráficos por Computador , Nanotecnologia/estatística & dados numéricos , Porosidade
19.
Biomech Model Mechanobiol ; 19(5): 1713-1724, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32056033

RESUMO

Cilia beating is a naturally occurring phenomenon that can be utilized in fluid transport in designing several biomechanical devices. Inspired by the ubiquity of bio-fluids (which are non-Newtonian), we report the characteristics of shear-rate-dependent viscosities on fluid flow generated by the wavy propulsion of magnetic cilia. We assume that the metachronal waves of these cilia form a two-dimensional wavy channel, which is filled with generalized Newtonian Carreau liquid. Galilean transformation is employed to relate fixed and moving frames. The constitutive equations are reduced under the classical lubrication assumption. The resulting fourth-order nonlinear differential equations are solved via a perturbation approach using the stream function. The effects of four dominant fluid parameters (shear thinning/thickening, power-law index, and zero- and infinite-shear-rate viscosity), magnetic parameter (Hartmann number), and metachronal wave parameters on fluid velocity, pressure rise per wavelength, and trapping phenomenon are shown in graphical results and explained thoroughly. This study could play an advisory role in designing a magnetic micro-bot useful in the biomedical industry.


Assuntos
Cílios/fisiologia , Fenômenos Magnéticos , Movimento (Física) , Reologia , Resistência ao Cisalhamento , Modelos Biológicos
20.
Comput Methods Programs Biomed ; 190: 105362, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32032806

RESUMO

Hydromagnetic second order velocity slip flow of viscous material with nonlinear mixed convection towards a stretched rotating disk is numerically examined here. Important slip mechanism of Buongiorno's nanofluid model i.e., Brownian motion and thermophoretic diffusion is incorporated in the mathematical modeling. Heat transport aspects are examined via Joule heating, thermal radiation and dissipation. Convective conditions at the stretchable surface of disk is implemented for the heat transport analysis. Chemical reaction subject to activation energy is also considered. Through appropriate transformations and shooting method the outcomes are computed and demonstrated graphically. The flow field, temperature, surface drag force, concentration and Nusselt number are deliberated subject to pertinent parameters. Total entropy rate is obtained. The outcomes show that magnetic field significantly affects the flow field as well as entropy rate.


Assuntos
Convecção , Entropia , Hidrodinâmica , Campos Magnéticos , Algoritmos , Simulação por Computador , Nanotecnologia
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