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2.
Sci Rep ; 11(1): 23652, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880373

RESUMO

The multi-phase flow of non-Newtonian through a divergent channel is studied in this article. Jeffrey fluid is considered as the base liquid and tiny gold particles for the two-phase suspension. Application of external electric field parallel to complicated capillary with net surface charge density causes the bulk motion of the bi-phase fluid. In addition to, electro-osmotic flow with heat transfer, the simultaneous effects of viscous dissipation and nonlinear thermal radiation have also been incorporated. Finally, cumbersome mathematical manipulation yields a closed-form solution to the nonlinear differential equations. Parametric study reveals that more thermal energy is contributed in response to Brinkman number which significantly assists gold particles to more heat attain high temperature, as the remedy for compressed or swollen capillaries/arteries.


Assuntos
Capilares/fisiologia , Tratamento Farmacológico , Hidrodinâmica , Eletricidade , Modelos Teóricos , Osmose
3.
Sci Rep ; 11(1): 16067, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373556

RESUMO

Present article reads three dimensional flow analysis of incompressible viscous hybrid nanofluid in a rotating frame. Ethylene glycol is used as a base liquid while nanoparticles are of copper and silver. Fluid is bounded between two parallel surfaces in which the lower surface stretches linearly. Fluid is conducting hence uniform magnetic field is applied. Effects of non-linear thermal radiation, Joule heating and viscous dissipation are entertained. Interesting quantities namely surface drag force and Nusselt number are discussed. Rate of entropy generation is examined. Bvp4c numerical scheme is used for the solution of transformed O.D.Es. Results regarding various flow parameters are obtained via bvp4c technique in MATLAB Software version 2019, and displayed through different plots. Our obtained results presents that velocity field decreases with respect to higher values of magnetic parameter, Reynolds number and rotation parameter. It is also observed that the temperature field boots subject to radiation parameter. Results are compared with Ishak et al. (Nonlinear Anal R World Appl 10:2909-2913, 2009) and found very good agreement with them. This agreement shows that the results are 99.99% match with each other.

4.
Sci Rep ; 11(1): 15944, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354197

RESUMO

This paper presents the analysis of transfer of heat and mass characteristics in boundary layer flow of incompressible magnetohydrodynamic Maxwell nanofluid with thermal radiation effects confined by exponentially shrinking geometry. The effects of Brownian motion and thermophoresis are incorporated using Buongiorno model. The partial differential equations of the governing model are converted in non-dimensional track which are numerically inspected with proper appliances of Runge-Kutta fourth order scheme.The significant effects of heat and mass fluxes on the temperature and nanoparticles volume fractions are investigated. By the increases in Lewis number between [Formula: see text] to [Formula: see text], the decrease in nanoparticle volume fraction and temperature is noted. With the change in the Prandtl constant that varies between [Formula: see text] to [Formula: see text], the nanoparticles volume fraction and temperature are dwindled. Nanoparticles volume fraction and temperature distribution increase is noted with applications of radiation constant. With consequent variation of thermophoresis parameter between [Formula: see text] to [Formula: see text], nanoparticles volume fraction and temperature distribution increases. It is also noted that the increase in thermophoresis parameter and Brownian parameter from [Formula: see text] to [Formula: see text], nanoparticles volume fraction decreases while temperature distribution increases.

5.
Sci Rep ; 10(1): 19300, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33168878

RESUMO

This comparative analysis studies the impact of two different nanoparticles Copper and Copper Oxide in two different partially ionized magnetofluid (water and kerosene oil mixed with Copper/Copper Oxide) flows over a linearly stretching surface. The impacts of electrons and ions collisions in the presence of the Cattaneo-Christov heat transfer model are also investigated. The effects of prominent parameters on velocity and temperature fields are depicted through graphical illustrations. A similarity transformation procedure is applied to transform the nonlinear partial differential equations to the ordinary one. Our numerical methodology is based upon the Finite difference method that is the default method in the bvp4c built-in function of the MATLAB scheme. Nusselt number and Skin drag coefficient are computed numerically and presented in tabular form for both types of nanofluids over a linear stretched surface. Our results demonstrate that the effects of CuO are dominant in comparison to the Cu on fluid velocity. The fluid temperature is more prominent in the case of Cu-water nanofluid when we increase nanoparticles concentration.

6.
Sci Rep ; 10(1): 18339, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110118

RESUMO

The study of nanofluids is the most debated subject for the last two decades. Researchers have shown great interest owing to the amazing features of nanofluids including heat transfer and thermal conductivity enhancement capabilities. Having such remarkable features of nanofluids in mind we have envisioned a mathematical model that discusses the flow of nanofluid comprising Nickel-Zinc Ferrite-Ethylene glycol (Ni-ZnFe2O4-C2H6O2) amalgamation past an elongated curved surface with autocatalytic chemical reaction. The additional impacts added to the flow model are the heat generation/absorption with nonlinear thermal radiation. At the boundary, the slip and the convective conditions are added. Pertinent transformations are affianced to get the system of ordinary differential equations from the governing system in curvilinear coordinates. A numerical solution is found by applying MATLAB build-in function bvp4c. Graphical illustrations and the numerically computed estimates are discussed and analyzed properly. It is comprehended that velocity and temperature distributions have varied trends near and away from the curve when the curvature parameter is enhanced. Further, it is comprehended that the concentration field declines for both homogeneous and heterogeneous reaction parameters.

7.
Sci Rep ; 10(1): 16832, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033287

RESUMO

The inadequate cooling capacity of the customary fluids forced the scientists to look for some alternatives that could fulfill the industry requirements. The inception of nanofluids has revolutionized the modern industry-oriented finished products. Nanofluids are the amalgamation of metallic nanoparticles and the usual fluids that possess a high heat transfer rate. Thus, meeting the cooling requirements of the engineering and industrial processes. Having such amazing traits of nanofluids in mind our aim here is to discuss the flow of nanofluid comprising Nickel-Zinc Ferrite and Ethylene glycol over a curved surface with heat transfer analysis. The heat equation contains nonlinear thermal radiation and heat generation/absorption effects. The envisioned mathematical model is supported by the slip and the thermal stratification boundary conditions. Apposite transformations are betrothed to obtain the system of ordinary differential equations from the governing system in curvilinear coordinates. A numerical solution is found by applying MATLAB build-in function bvp4c. The authentication of the proposed model is substantiated by comparing the results with published articles in limiting case. An excellent concurrence is seen in this case. The impacts of numerous physical parameters on Skin friction and Nusselt number and, on velocity and temperature are shown graphically. It is observed that heat generation/absorption has a significant impact on the heat transfer rate. It is also comprehended that velocity and temperature distributions have varied behaviors near and far away from the curve when the curvature is enhanced.

8.
Entropy (Basel) ; 21(7)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-33267356

RESUMO

Our objective in the present study is to scrutinize the flow of aqueous based nanofluid comprising single and multi-walled carbon nanotubes (CNTs) past a vertical cone encapsulated in a permeable medium with solutal stratification. Moreover, the novelty of the problem is raised by the inclusion of the gyrotactic microorganisms effect combined with entropy generation, chemical reaction, and thermal radiation. The coupled differential equations are attained from the partial differential equations with the help of the similarity transformation technique. The set of conservation equations supported by the associated boundary conditions are solved numerically with the bvp4c MATLAB function. The influence of numerous parameters on the allied distributions is scrutinized, and the fallouts are portrayed graphically in the analysis. The physical quantities of interest including the skin friction coefficient and the rate of heat and mass transfers are evaluated versus essential parameters, and their outcomes are demonstrated in tabulated form. For both types of CNTs, it is witnessed that the velocity of the fluid is decreased for larger values of the magnetic and suction parameters. Moreover, the value of the skin friction coefficient drops versus the augmented bioconvection Rayleigh number. To corroborate the authenticity of the presented model, the obtained results (under some constraints) are compared with an already published paper, and excellent harmony is achieved in this regard.

9.
Sci Rep ; 8(1): 3709, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29487368

RESUMO

A mathematical model is envisaged to study the axisymmetric steady magnetohydrodynamic (MHD) Carreau nanofluid flow under the influence of nonlinear thermal radiation and chemical reaction past a radially stretched surface. Impact of heat generation/absorption with newly introduced zero mass flux condition of nanoparticles at the sheet is an added feature towards novelty of the problem. Further, for nanofluid the most recently organized model namely Buongiorno's model is assumed that comprises the effects thermophoresis and Brownian motion. Utilizing suitable self-similar transformations, the set of partial differential equations with high nonlinearity are converted into a dimensionless system of ordinary differential equations. Set of these transmuted equations are numerically solved by MATLAB built-in function bvp4c. Impact of germane parameters on all involved profiles are plotted to examine the heat and mass transfer characteristics. This study reveals that the temperature distribution is an escalating function of the heat generation and nonlinear radiation parameters. Also, it is noted that the incrementing values of chemical reaction parameter lowers the nanoparticles concentration profile. A comparison of the present investigation with already published explorations in limiting case is also added to authenticate the presented results; hence reliable results are being presented.

10.
J Endourol ; 32(5): 410-416, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29495894

RESUMO

OBJECTIVE: To evaluate the outcomes of laparoendoscopic single-site nephrolithotomy (LESS-NL) for symptomatic caliceal diverticular calculi. PATIENTS AND METHODS: From November 2009 to March 2014, 11 cases of LESS-NL with a homemade single-port device for caliceal diverticular calculi were performed by a single experienced laparoscopic surgeon. All patients were assessed at postoperative 1 month, 1 year, and 3 years for symptom-free status and by CT for stone-free and caliceal diverticular obliteration status. All complications were categorized by the Clavien-Dindo classification. Demographic parameters and postoperative outcomes were retrospectively analyzed. RESULTS: All procedures were effectively performed without conversion to open or conventional laparoscopic surgery. Median patient age was 53 years (range 22-73), and median diverticular size was 26 mm (range 15-58). Six patients (54.5%) had multiple stones, and five patients (45.5%) had a single stone; median stone size was 20.6 mm (range 12.1-66.4). The transperitoneal approach was used in seven patients (63.6%) and retroperitoneal approach in four patients (36.4%). Median operative time was 161 minutes (range 110-250), median estimated blood loss was 50 mL (range 20-400), and median hospital stay was 4 days (range 3-6). An additional needlescopic instrument was used in five cases (45.5%). There were three cases (27.3%) of grade I complications (two postoperative fever, one ileus), and no intraoperative or major complications. Median visual analog scale score significantly improved by discharge day (from 4.9 preoperatively to 1.4; p = 0.003). After a median follow-up of 38 months (range 36-41), all patients were symptom free with no evidence of stone or caliceal diverticulum on imaging. CONCLUSIONS: LESS-NL is a safe, feasible, and definitive treatment option for symptomatic caliceal diverticular calculi.


Assuntos
Divertículo/cirurgia , Cálculos Renais/cirurgia , Cálices Renais/cirurgia , Laparoscopia/métodos , Nefrostomia Percutânea/métodos , Adulto , Idoso , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
11.
Entropy (Basel) ; 20(12)2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33266654

RESUMO

The present study characterizes the flow of three-dimensional viscoelastic magnetohydrodynamic (MHD) nanofluids flow with entropy generation analysis past an exponentially permeable stretched surface with simultaneous impacts of chemical reaction and heat generation/absorption. The analysis was conducted with additional effects nonlinear thermal radiation and convective heat and mass boundary conditions. Apposite transformations were considered to transform the presented mathematical model to a system of differential equations. Analytical solutions of the proposed model were developed via a well-known homotopy analysis scheme. The numerically calculated values of the dimensionless drag coefficient, local Nusselt number, and mass transfer Nusselt number are presented, with physical insights. The graphs depicting the consequences of numerous parameters on involved distributions with requisite deliberations were also a part of this model. It is seen that the Bejan number is an increasing function of the thermal radiation parameter.

12.
Int J Urol ; 21(5): 466-72, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24877252

RESUMO

OBJECTIVES: We investigated whether multiparametric magnetic resonance imaging is appropriate to localize prostate cancer foci in Koreans. METHODS: A total of 141 prostate cancer foci in 115 prostate specimens from patients who had undergone radical prostatectomy with preoperative 3 Tesla multiparametric magnetic resonance imaging including T2-weighted imaging, diffusion weighted imaging and magnetic resonance spectroscopy. Differences in the histopathological findings between detected and undetected prostate cancer foci on multiparametric magnetic resonance imaging were investigated. RESULTS: The mean tumor size was 1.9 cm, and 31.9%, 48.9%, and 19.9% of the patients had Gleason scores of 6, 7, or ≥8, respectively. The detection rates of prostate cancer foci were 54.6%, 57.4%, 55.3%, and 45.4% on multiparametric magnetic resonance imaging, T2-weighted imaging, diffusion weighted imaging, and magnetic resonance spectroscopy, respectively. On multivariate analysis, tumor size ≥1.5 cm (odds ratio 3.1; 95% confidence interval 1.31­7.49), Gleason score >7 (4 + 3; odds ratio 2.9; 95% confidence interval 1.05­8.05), and a malignant epithelium/stroma ratio of ≥60% (odds ratio 2.9; 95% confidence interval 1.14­7.20) were significant independent predictors of prostate cancer foci detection on multiparametric magnetic resonance imaging and diffusion weighted imaging. In a multivariate linear model analysis, the apparent diffusion coefficient value was inversely associated with maximum tumor diameter (ß = −0.242, P < 0.05), Gleason score (ß = −0.234, P < 0.05)and high malignant epithelium/stroma ratio (ß = −0.229, P < 0.05). CONCLUSIONS: Distinct histological differences between prostate cancer foci that were detected and missed by multiparametric magnetic resonance imaging can be identified. Despite limitations, multiparametric magnetic resonance imaging seems useful for determining prostate cancer in Korean patients, particularly with Gleason score >7 and tumor diameter>1.5 cm.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/patologia , Idoso , Povo Asiático , Imagem de Difusão por Ressonância Magnética , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Int J Biol Sci ; 9(7): 693-701, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23904793

RESUMO

Intergenomic F1 hybrids between L. auratum x L. henryi and their BC1 progeny were investigated through genomic in situ hybridization technique (GISH) to determine their potential value in lily breeding. We confirmed that F1 intergenomic hybrids possessed a set of chromosomes (x=12) from both parents and that flowers of the F1 auratum × henryi hybrid showed an intermediate morphological phenotype. Pollen size, viability and germination ability were measured through microscopic observations. F1 intergenomic hybrids produced a relevant frequency of 2n-gametes, which were successfully used to perform crosses with Oriental hybrids, resulting in the triploid Oriental Auratum Henryi (OAuH) hybrid. Twenty BC1 plants were generated by crossing between four different Oriental hybrid cultivars and F1 AuH hybrids using an in vitro embryo rescue technique, after which the genome constitution and chromosome composition were analyzed by GISH. All plants were triploid, showing 12 from female parents (diploid Oriental hybrid) and 24 from male parents (diploid F1 AuH hybrid). Overall, 16 out of 20 BC1 progeny possessed recombinant chromosomes with 1-5 crossover sites per plant. Cytological analysis of 20 BC1 plants by GISH verified that the occurrence of 2n pollen formation in all F1 AuH hybrids was derived from the FDR (first division restitution) mechanism, in which the genome composition of all BC1 plants possess 12 Oriental + 12 L. auratum + 12 L. henryi chromosomes. Allotriploids derived from the AuH hybrid were used as female for crossing with the diploid Oriental hybrid cultivar 'Sorbonne' and considerable numbers of plants (0-6.5 plants per ovary) were only obtained when female OAuH (BC1) triploids were used. Taken together, the results of this study indicate that production and analysis of F1 AuH hybrids and their progeny through sexual polyploidization can be useful for efficient creation of important horticultural traits.


Assuntos
Cromossomos de Plantas , Células Germinativas Vegetais , Lilium/genética , Poliploidia , Cruzamentos Genéticos , Genoma de Planta , Hibridização Genética , Hibridização In Situ , Pólen/fisiologia
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