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In the present work, an autogenous TIG welding technique was used to join 2 mm thick sheets of a TiNi binary shape-memory alloy at three different values of current (80 A, 90 A and 100 A). The effects of the welding current on microstructures, residual stresses, mechanical properties and nano-mechanical behaviour were investigated. Microstructure analysis revealed that with an increase in current, the columnar grain size decreased, which had a significant effect on mechanical properties. The tensile strength of the weldment at 100 A was ∼92% of that base alloy’s (BA) and elongation of approx. 14%. The reduction in elongation was due to the formation of Ti2Ni and Ti3Ni4 type precipitates. The microhardness profile in all the weldments showed an increase of approx. 30% between the base alloy and the fusion zone due to the formation of Ti2Ni and Ti3Ni4 type precipitates during welding. Residual stress analysis suggested the tensile residual stresses in the longitudinal direction are minimum in the weldment performed at 100 A. The nanoindentation results revealed that the weldment obtained at 100 A had the least plastic deformation (∼45.5% less than the 80 A weldment) owing to a decrease in inter-dendritic spacing and high proportion of IMCs: Ti2Ni and metastable Ni4Ti3.

Owing to the improved thermophysical properties of nano-materials, the nanofluid convey novel applications in industries, engineering as well as bio-medicals. With high efficiency performances, the nanoparticles include applications in various cooling and heating systems, energy production, aerospace engineering, thermal extrusion, bio-medical applications like treatment of diseases, brain tumour, surgical applications and many more. Moreover, the magneto-nanofluids have the characteristics in the flow of blood in the human artery. The current analysis deals with the free convective unsteady flow of viscous nanofluid subject to the magnetic force over a vertical plate in presence of porous space. The heat transfer phenomenon is accessed by utilizing the additional features like Joule heating, viscous dissipation and absorption coefficients. In addition to the volume fraction of the nanofluid, the effect of the chemical reaction is also introduced. The solution procedure for the modified time-dependent boundary value problem is performed by using the code in-build MATLAB namely Built-in-Shooting method. The change in velocity, temperature and concentration of nano-materials is examined through various graphs. The physical consequences of flow parameters like porosity parameter K p 1 ⩽ K p ⩽ 3 , thermal Grashoff number Gr 1 ⩽ G r ⩽ 3 , solutal Grashoff number Gc 1 ⩽ G c ⩽ 3 , magnetic field parameter M 1 ⩽ M ⩽ 3 , thermal radiation parameter Nr 0.1 ⩽ N r ⩽ 1 , radiation absorption parameter Q 0 ⩽ Q ⩽ 0.5 , Prandtl number Pr 2 ⩽ Pr ⩽ 21 , Eckert number Ec 0 ⩽ E c ⩽ 0.4 , heat source S - 0.2 ⩽ S ⩽ 0.2 , chemical reaction parameter Kc 1 ⩽ K c ⩽ 4 , nanoparticles volume fraction ϕ 0.0 ⩽ ϕ ⩽ 0.1 , Lewis number Le 1 ⩽ L e ⩽ 10 on velocity, temperature and concentration distributions is graphically analyzed. The results show that skin friction coefficients decline with buoyant forces. A lower numerical variation in Nusselt number is resulted with heat source parameter. Moreover, a sharp fall in nanofluid concentration is noticed with increment of chemical reactants and Lewis number.

This contemporary study is done to analyze the comparative study of hybrid nanofluids motion due to semi-infinite asymmetric channel with contracting and expanding porous walls orthogonally. Boundary conditions considered are convective conditions. Hybrid nanofluids consist of more than two nanoparticles. Purpose of nanofluid is to enhance the heat transfer characteristics by adding nanoparticles into base fluid. When we add two nanoparticles collectively to form nanofluid than it is more useful. Maganese Zinc ferrite and Nickle Zinc ferrite are used as nanoparticles and engine oil and Kerosene oil are considered in place of base fluid. Nonlinear heat source sink effect is considered along with activation energy. Darcy Forchheimer porous medium is considered in momentum equation. We have introduces suitable transformations to get ODE’s from PDE’s. Homotopy analysis method is used to find the convergent solution. For more accuracy tables are also drawn for convergent solution. Velocity for M n Z n F e 2 O 4 - N i Z n F e 2 O 4 - C 10 H 22 - C 8 H 18 is lowest among all. Impact of important parameters along velocity, temperature, concentration, skin friction and Nusselt number is seen through graphs. For positive values of wall contraction (or expansion) rate parameter velocity of the fluid enhances. Motion slows down for greater Forchheimer number. Temperature rises via thermal Biot number. Concentration profile is increasing with larger estimation of activation energy.

Ti50Ni50−xCux (x = 10, 15, 20, 25) ternary shape memory alloys (SMAs) were developed in an arc melting furnace and characterized by differential scanning calorimetry (DSC), atomic force microscopy (AFM), scanning electron microscopy (SEM), and x-ray diffraction (XRD) techniques. The transformation temperatures and thermal hysteresis showed a decreasing trend with the successive addition of Cu. The SEM and XRD results showed the formation of nano-scaled Ti(Ni,Cu)2 type precipitates along with small densities of Ti2Ni type precipitates. The precipitation of fine Ti(Ni,Cu)2 type precipitates was found to be sensitive toward the presence of lattice defects. It is expected that in TiNiCu based SMAs, the precipitation mechanism of Ti(Ni,Cu)2 type precipitates depends upon the relative ease of diffusion of Cu toward the heterogeneous nucleation sites provided by the lattice defects. Surface topographic characteristics of the alloys were also investigated by the AFM. The AFM results showed that the fine acicular martensite structure transformed to coarser acicular martensite with successive addition of Cu followed by different thermal treatments. Hardness showed direct correlation with the Cu content and the thermal treatment employed, whereas cold workability was shown to decrease with the successive addition of Cu in TiNiCu based SMAs.

A 50-year old diabetic male presented with cough, breathlessness, fever, and chest pain. Clinical and radiological evaluation revealed a right-sided pyopneumothorax. Surgical drainage with tube thoracostomy was performed. Pleural fluid cultures grew Enterococcus fecium as a sole organism. Our patient was treated with vancomycin and amikacin with an excellent clinical response. Enterococci are rarely implicated in the lower respiratory tract and pleural infections and are not usually considered if initiating empirical treatment. Their intrinsic resistance to empirically used antibiotics may complicate the course of the disease. Hence initial Gram staining and expeditious microbiological isolation with susceptibility testing is warranted in all cases. Gram-positive aerobes, notably staphylococcus followed by streptococcus and pneumococcus, are the commonly encountered organisms in pleural infections.

Aspergillus flavus was used to produce alkaline protease. Solid state fermentation (SSF) strategy was adopted to explore the most favorable physical and nutritional conditions for enzyme production. Maximum production was achieved at pH 6.0 and a temperature of 30 °C after 84 h of growth period. For the optimization of the chemical parameters, different carbon and nitrogen sources were used including glucose, fructose, sucrose, ammonium sulphate, and urea. Maximum production was observed with 0.3% concentration of all the compounds. Ammonium sulphate salting out and gel chromatography was used to purify the enzyme. The enzyme was completely precipitated out at 80% saturation. The value of Vmax was 3.9 U/mL, while the value of Km was 1.9 mg/mL. The enzyme was tested for its compatibility with a few famous detergents available on the market. With the alkaline protease under study, the enzyme displayed a maximum retention of its activity i.e. 80.8% in the presence of commercial detergent Surf excel. The activity dropped down to 61.5% when the enzyme was allowed to work in the presence of another locally used detergent, i.e., Bonus. Protease production from A. flavus was carried out on rice bran and wheat bran and the wheat bran gave better results.

The present analysis deals with two-dimensional magneto-Williamson liquid bounded by a stretching surface. Impacts of viscous dissipation, heat generation/absorption and nonlinear thermal radiation are also considered. Entropy generation minimization in flow of Williamson fluid is discussed. Convergent solutions of resulting problems are obtained. Nusselt number, skin friction coefficient, temperature and velocity are discussed. Velocity reduces for larger Williamson fluid parameter. Temperature enhances for larger radiation parameter and Biot number. Entropy generation and Bejan number are increased for larger Biot number, while both have opposite behavior for Brinkman number.

Here, we communicate the peristalsis of single- and multi-walled CNTs through nonlinear porous, non-uniform propagating channel boundaries. Non-uniform channel boundaries are of asymmetric characteristics. Flow equations are modeled by taking variable viscosity, linear and nonlinear porous medium (i.e., Darcy and Darcy–Forchheimer), nonlinear thermal radiation, mixed convection, heat generation and absorption aspects. Convective heat transfer aspects are at the convectively heated surface. The entropy generation rate is modeled via the second law of thermodynamics. Modeled equations are simplified with the help of long wavelength assumption. Dimensionless system of equations with respective boundary conditions is solved numerically via built-in shooting algorithm in Mathematica 8 software. Further, these numerical results are directly received in the form of curves. Such curves are made for velocity, temperature, pressure gradient, trapping, entropy rate and Bejan number. Heat transfer rate at lower and upper walls is achieved through bar charts.

The bioconvection flow of tiny fluid conveying the nanoparticles has been investigated between two concentric cylinders. The contribution of Lorenz force is also focused to inspect the bioconvection thermal transport of tiny particles. The tiny particles are assumed to flow between two concentric cylinders of different radii. The first cylinder remains at rest while flow is induced due to second cylinder which rotates with uniform velocity. Furthermore, the movement of tiny particles follows the principle of thermophoresis and Brownian motion as a part of thermal and mass gradient. Similarly, the gyro-tactic microorganisms swim in the nanofluid as a response to the density gradient and constitute bio-convection. The problem is modeled by using the certain laws. The numerical outcomes are computed by using RKF -45 method. The graphical simulations are performed for flow parameters with specific range like 1≤Re≤5, 1≤Ha≤5, 0.5≤Nt≤2.5, 1≤Nb≤3, 0.2≤Sc≤1.8, 0.2≤Pe≤1.0 and 0.2≤Ω≤1.0. It is observed that the flow velocity decreases with the increase in the Hartmann number that signifies the magnetic field. This outcome indicates that the flow velocity can be controlled externally through the magnetic field. Also, the increase in the Schmidt numbers increases the nanoparticle concentration and the motile density.

The thermo-dynamical modeling is a powerful tool for predicting the optimal melting of heat transfer; this is because there is a good correlation between numerical and analytical heattransfers via thermodynamic predicted results. A mathematical model is constructed underflow of a non-Newtonian (Reiner-Philippoff) fluid based on certain assumptions. Such mathematical model flow is handled by invoking similarity solutions for governing equations. The obtained system of nonlinear equations is solved numerically by utilizing fourth-fifth order Runge-Kutta-Fehlberg method. The consequences of distinguished parameters onfluid flow are analyzed in details through the plotted graphic visuals. Physical quantities are also considered numerically by tables. The claimed results reveal that the velocity profile reduce due to Forchheimer parameter and porosity parameter. The growing nature of temperature field is observed against temperature ratio parameter. The numerical values of local Nusselt number decline with radiation parameter and surface heating parameter. The obtained results presents novel role in the heat transfer phenomenon, electronic cooling, microheat pipes, electronic cooling, reaction processes, nuclear reactors etc.

Climatic changes are associated with fluctuations spanning over a period of three decades as a classic period of computing weather trends all around the world which, by studies till now, was proved to be harmful for life on earth. Natural processes going on in this earth were observed to be impacted significantly by these variations in our climate that are the result of anthropogenic activities. Rapid growth in population demands more resources for their survival that includes the basic amenities of livelihood, i.e., nutrition, energy, and housing. Limited resources in combination with the risk of climatic changes are in fact a big problem that must be solved before it results in nonreversible damage. Modeling is the advanced approach to study climate change. Right after the Second World War, predominantly in the USA, by the end of the 1960s, representatives were being presented with the model’s findings, which strongly supported the concept that the persistent intensification in greenhouse gas (GHG) emissions caused by human activities have completely changed the overall impact of global climate. With the passage of time, more advancement in modeling was observed; first of all, conceptual models were formed; those were replaced by analog models and then energy balance models were introduced by researchers. In agricultural systems, modeling as an essential tool is accomplished by scientists from different disciplines that has contributed for six decades in this field. Models have been used in ecosystem studies, hydrology, climate, crops, livestock and Hadley Climate model version 3 (HadCM3) is recently commonly used and several other Global climate models (GCMs) are in practice apart from statistical models like Statistical Downscaling Model (SDSM) are prominent among others for analytical climatic data studies. In order to study the climate changes; different climate projection scenarios have been made on the basis of previously provided data, i.e., rainfall, temperature, carbon dioxide and GHG emissions, and other components. On the basis of these scenarios, future predictions are likely to be more realistic and hopefully helpful for addressing the changing climatic situations across the globe and proactively devising mitigation practices to save the masses.

The main aim of this study is to apply the recent definition of fractional derivative i.e. Atangana-Baleanu time-fractional derivative on second grade fluid flowing on an infinite plate under the MHD (magnetohydrodynamics) effect. The flow is studied under both Darcy's law and heat transfer. To find out the analytical solution, the Laplace transformation technique is utilized on the obtained non-dimensional governing equations momentum and heat equations with initial and boundary conditions. To enhance the innovation of this study, the graphical and numerical comparison of heat and momentum equation is analyzed with different parameters for different values. Main results and conclusions are accomplished at the end of this work. The increasing change in temperature profile is noticed with fractional parameter and Grashof number. The velocity profile increases with the Prandtl number while a reverse trend is noted for the temperature profile.

Background: Few studies have assessed the relation of hyperuricacidemia with the acute coronary syndrome (ACS). This study investigated the association between high uric acid levels with the presence and severity of ACS. Methods: Three hundred and seventy patients having angiographic evidence of atherosclerosis (CAD + case group) compared to 170 patients with no luminal stenosis (n=110) or with

Equiatomic TiNi alloy composites, reinforced with 0, 5, 10, and 15 vol% ZrO2, were synthesized using conventional sintering approach. Equiatomic TiNi pre-alloyed powder and ZrO2 powder were mixed in planetary ball mill for 6 h followed by cold compaction and pressure-less sintering, respectively. The sintered density was found to vary inversely with the addition of ZrO2 content. The X-ray diffraction (XRD) spectra have shown the formation of multiple-phases which were resulted from the decomposition of the B19′ and B2 phases of the equiatomic TiNi alloy due to the addition of ZrO2 and higher diffusion rate of Ni than that of Ti in the alloy composite. An increase in hardness was noted due to the addition of ZrO2, measured by micro and nanoindentation techniques. Potentiodynamic polarization scan revealed a 10% decrease in the corrosion rate of the composite containing 10 vol% ZrO2. Electrochemical impedance spectroscopy (EIS) results indicated an increase in passive layer resistance (Rcoat) due to the increase in charge transfer resistance (Rct) caused by the reduced leaching of ions from the surface.

A substantial proportion of subjects with autosomal recessive retinitis pigmentosa (arRP) or Usher syndrome type II (USH2) lacks a genetic diagnosis due to incomplete USH2A screening in the early days of genetic testing. These cases lack eligibility for optimal genetic counseling and future therapy. USH2A defects are the most frequent cause of USH2 and are also causative in individuals with arRP. Therefore, USH2A is an important target for genetic screening. The aim of this study was to assess unscreened or incompletely screened and unexplained USH2 and arRP cases for (likely) pathogenic USH2A variants. Molecular inversion probe (MIP)-based sequencing was performed for the USH2A exons and their flanking regions, as well as published deep-intronic variants. This was done to identify single nucleotide variants (SNVs) and copy number variants (CNVs) in 29 unscreened or partially pre-screened USH2 and 11 partially pre-screened arRP subjects. In 29 out of these 40 cases, two (likely) pathogenic variants were successfully identified. Four of the identified SNVs and one CNV were novel. One previously identified synonymous variant was demonstrated to affect pre-mRNA splicing. In conclusion, genetic diagnoses were obtained for a majority of cases, which confirms that MIP-based sequencing is an effective screening tool for USH2A. Seven unexplained cases were selected for future analysis with whole genome sequencing.

Motivated by bio-chemical systems and ciliated propulsion, we consider the steady laminar flow from a non-uniform wavy channel adjacent to a saturated porous medium which has been investigated analytically using an integration technique. A highly permeability domain is considered. We employed a sinusoidal complex wavy relation for the ciliated walls. A mathematical relation was used to convert the rheological equations from $$\big(\bar{X},\bar{\xi }\big)$$ coordinate system to a $$\big(\bar{x},\bar{\xi }\big)$$ dimensionless system. These rheological equations are simplified under two biological assumptions, one is creeping phenomena, and the second one is long-wavelength approximation. The solution of governing equations is obtained through Mathematica software 10.0 with the help of integration technique in a wave frame. The impacts of embedded hydro-mechanical parameters on the rheological features are studied. The boundary layer phenomena are obtained in the velocity profile under larger magnetic and porosity effects. The magnitude of pressure gradient is reduced under larger strength of magnetic and porosity effects. The cilia length parameter has a dynamic role in enhancement of the pressure gradient. The larger strength of the thermophoretic parameter has remarkable effects in augmentation of volumetric fraction, heat and mass transfer phenomena. The outcomes of current investigation are applicable in energy systems, manufacturing of ciliated micro-pumps, petroleum engineering, thermal augmentation of physiological and chemical fluids, and industrial magnetic materials processing.

Our main focus here is to analyze the chemically reactive flow of Prandtl–Eyring nanofluid. Flow is caused by linear stretching of sheet. Heat transfer characteristics are examined subject to nonlinear radiative flux and heat source/sink. Moreover Joule heating and dissipation effects are considered. Entropy optimization is expressed as a function of temperature, velocity and concentration. Total entropy has been calculated. Buongiorno nanofluid model which incorporates important slip mechanisms like Brownian motion and thermophoresis diffusion is used. Chemical reaction is considered along with activation energy. Suitable transformations are implemented to convert the governing expressions into ordinary one. Built-in-shooting technique is used for the solution development. Results for the velocity, entropy, temperature, Bejan number and concentration are presented graphically. Particular attention is given to quantities of engineering interests such as skin friction coefficient and Nusselt and Sherwood numbers.

Present research addresses entropy generation in unsteady flow of viscous material. Flow by a stretchable rotating disk is examined. Applied magnetic field is considered. Energy equation consists of viscous dissipation and thermo-diffusion and diffusion thermo effects. Chemical reaction with activation energy is implemented. Through implementation of second law of thermodynamics the total irreversibility rate is calculated. Mathematical expressions for residual errors are presented. Convergent series solutions by homotopic procedure are developed. Influences of pertinent variables for velocity, entropy generation, temperature, Bejan number and concentration fields are arranged. Moreover the computational analysis of skin friction coefficient and Nusselt number is presented in Tables 2 and 3. It is concluded that entropy generation and Bejan number show opposite impact versus Brinkman number.

Flow of Williamson nanofluid over a stretching sheet is addressed. Entropy generation is modeled by second thermodynamics law. Present model examines the momentum, heat, mass and entropy generation. Joule heating, viscous dissipation and chemical reaction are considered in the modeling. Fluid is conducting electrically through applied magnetic field. Optimal homotopy analysis method is implemented for the solutions. Series solutions convergence by residual errors is ensured. Outcomes of magnetic parameter. Prandtl number, Brownian motion, chemical reaction parameter, thermophoresis and Brinkman number are examined. Moreover coefficient of skin friction and heat transfer rate (Nusselt number) are computed and examined. Heat transfer rate by Brownian parameter is increased. Furthermore entropy generation rate increases for higher magnetic parameter.

Here entropy generation effectiveness in hydromagnetic flow of viscous fluid by permeable rotating disk is examined. Partial slip effect is studied. Formulation is based on mixed convection and nonlinear radiation. A new chemically reacted species model featuring activation energy is taken into account. Entropy analysis is elaborated employing thermodynamic second relation. The Von-Karman approach is utilized for non-dimensionalization process. Shooting scheme is implemented for the computations of solutions. The characteristics of magnetic and slip parameters, thermal and solutal buoyancy variables, Prandtl number, temperature difference parameter, radiative parameter, dimensionless reaction rate, activation energy factors, heat generation/absorption factor and Schmidt number are discussed for concentration, velocity and thermal fields. Surface drag forces, heat/mass transfer rates, entropy generation rate and Bejan number are addressed.

The present study addresses the effects of Hall current and heat generation on peristaltic flow of conducting pseudoplastic fluid in an inclined channel with compliant walls. Mathematical modeling is given in presence of Soret and Joule heating effects. The relevant equations are computed subject to long wavelength and low Reynolds number approximation. Equations containing material parameters are nonlinear. Perturbation technique leads to solution expressions. Graphical results of velocity, temperature, concentration and heat transfer rate are analyzed for the pertinent parameters. Trapping phenomenon is also discussed.

Here, flow of magnetite nanoliquid by nonlinear stretching sheet is considered. Heat source/sink and nonlinear radiation are explored. Velocity and thermal slip aspects in Fe3O4-nanoliquid flow modelling are retained. Present study focuses on entropy generation analysis. Viscous dissipation, non-linear thermal radiation and joule heating irreversibilities are accounted. Formulated problems computed by Optimal Homotopy algorithm. The velocity, temperature, entropy generation, Bejan number, skin friction and heat transfer rate are discussed. It is observed that entropy generation rates enhances for Brinkman number and solid volume fraction of nanoparticles while reverse behavior of Bejan number holds.

Here peristalsis of Carbon nanotubes is performed between non-uniform propagating waves channel/tube. Viscosity of the material is considered dependent upon temperature here. Thermally radiative aspects are considered through linear term of heat flux. Channel boundaries retain the momentum and thermal slip characteristics. Iijima suggested physical quantities for single and multiple WCNTS are taken. Conservation principles (i.e. Mass, momentum and energy) are used to modeled the flow. Later on lubrication assumptions are utilized to simplified such equations. Exact solution for stream function, velocity and temperature is carried out. Further pressure rise per wavelength is plotted via numerical integration. Effective heat transfer rate is analyzed through bar charts.

Our goal in this attempt is to model a nonlinear stretchable flow of a radiative viscous liquid with magnetohydrodynamics. Flow caused is due to a unsteady stretching surface with variable thickness. Consideration of thermal radiation effect characterizes the heat transfer process. Induced electric and magnetic fields are not accounted for. Appropriate transformations gave nonlinear systems. Modern methodology, i.e., НAM, is implemented for the computational process. Velocity and temperature are plotted for influential variables which are important in this problem. Moreover, surface drag force and heat transfer rate are computed and discussed. Velocity field is noted to decay the function of the larger Hartman number whereas opposite situation for temperature is examined via larger radiation parameter.

The present article reports the impact of temperature on optical properties of InGaAs/GaAsSb/InAlAs nano-scale heterostructure which has been assumed to grow on GaAs substrate. For this heterostructure, the optical properties such as optical gain and transition wavelength have been simulated under the variable temperature with the help of 6 band k.p approach. The outcomes of the calculations inform that the increased temperature can reduce the optical gain appreciably with the red shift in wavelength in near infrared (NIR) region.

Hospitals have a pivotal role in reducing health inequities for indigenous people and other marginalised groups, argue Anna Matheson and colleagues