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In recent years, nanotechnological research has introduced hybrid nanofluids, which are advanced fluids with augmented thermal properties that give better results than regular nanofluids. The thermal transfer characteristics of the Falkner-Skan flow of MgO-MoS2/Engine oil hybrid nanofluid induced by a wedge surface with thermophoresis and Brownian motion are numerically investigated. The main objective of this research is to examine the augmented thermal transport behavior of Casson and Carreau hybrid nanofluids. The equations that arise are solved by adopting the bvp5c scheme in MATLAB software. Plots and numerical values illustrate the stimulus of various pertinent parameters on the flow-determining factors such as velocity, thermal and concentration fields, wall friction, energy, and mass transports. The rate of energy transport in the Carreau hybrid nanofluid is significantly larger than that of the Casson hybrid nanofluid. The implication of 5% volume of MgO-MoS2 nanoparticles enhances the rate of thermal transport by 53% in the Carreau fluid and 47% in the Casson fluid, respectively. This research holds potential for applications in geothermal energy systems. [ABSTRACT FROM AUTHOR]

AbstractA numerical investigation is performed to scrutinize the enhanced thermal transmission of Carreau nanoliquid above an incessantly moving thin needle in the occurrence of nonuniform heat rise/fall effects. The arising system of nonlinear coupled equations is exercised numerically by employing a suitable numerical scheme, i.e. bvp5c Matlab solver. The prime motive of this research is to determine the effectual thermal conductivity of the nanoliquid by using Maxwell/Xue models to achieve enhanced energy transmission. The stimulus of pertinent constraints upon the flow factors, viz. velocity and thermal gradients, are illustrated through plots. Also, the wall friction and energy transmission rate are bestowed via plots and tabular values. The outcomes reveal that the Xue nanomodel augments the thermal transmission rate of the nanofluid to a greater extent than the Maxwell nanomodel. This research holds potential for applications in geothermal power production. [ABSTRACT FROM AUTHOR]

This article investigates the heat transmission rate in hybrid and tri-hybrid particles that emerged in Oldroyed-B blood flow flowing through wedge shape arteries. The rate type Oldroyd-B flow model is considered to examine the behavior of relaxation and retardation times. The transmuted nondimensional conditions and boundary restrictions are solved using the bvp5c technique. It is observed that the heat transmission rate is high for the tri-hybrid (GO-Al2O3-TiO2) blood flow combination compared to the hybrid (Al2O3-TiO2) blood combination. This study can deliver a vibrant opinion concerning heat transmission behavior and the blood flow nature in a wedge shape artery. [ABSTRACT FROM AUTHOR]

This paper examines the thermal transfer attributes of ZnO-H2O Walter's-B nanoliquid flow alongside an upright cone in the bearing of slip mechanism, radiative heat flux, and non-uniform heat source. We adopted suitable similarities to convert the nonlinear PDEs into ODEs and solved the transformed governing system by employing the bvp5c solver package in Matlab software. The prime novelty of this research is to compute the effective thermal diffusivity of the nanoliquid via the Maxwell and Xue nanomodels. Further, simultaneous results are deliberated for Maxwell and Xue cases via pictorial outcomes under various controlling limitations, such as velocity slip, radiative heat flux, buoyancy, viscoelastic, and volume fraction of nanomaterial. The thermal transmission rate of nanoliquid reported by the Xue nanomodel is higher than the Maxwell nanomodel. Therefore, the Xue nanomodel effectively works to enhance the thermal conductivity of the liquids with viscoelastic nature. Further, this study is helpful in industrial processing, where control over heat transport is required. [ABSTRACT FROM AUTHOR]

In thermal power and manufacturing processes, solar energy utilization has grown extensively. This work investigates the heat diffusion characteristics of an unsteady Oldroyd-B hybrid nano liquid flow across an expanding cylinder. A constant magnetic field is applied in the radial path in the presence of radiant heating, generation, or sinks, and Cattaneo-Christov (CC) heat flow. Hybrid nano liquid composed of two distinct nanoparticles (CoFe 2 O 4 and Fe 3 O 4) embedded in ethylene glycol as the primary fluid. A mathematical model was established and reconstructed into a nonlinear ordinary differential equations (ODEs) system, utilizing the proper likeness conversion. The Matlab inbuilt bvp5c scheme determines the problem's numerical solution. We observed the instabilities in the flow and thermal area and also the local Nusselt number impacted by the pertinent dimensionless characteristics. The findings are addressed graphically and tabularly for several nanoparticle shapes (spherical, brick, and platelet). It has been discovered that spherical shapes are found to have a faster heat conduction rate than brick and platelet nanoparticle shapes for the considered flow case. While unsteadiness parameters tend to increase the temperature field, the augmentation of the temperature relaxation factor reduces the energy profile. • Effective solar energy usage in Parabolic Trough Solar Collectors (PTSC). • Discrete outcomes for spherical, brick, and platelet-shaped nanoparticles. • Spherical-shaped ferro particles showed better heat transfer rates than platelet and brick-shaped particles. • Thermal radiation improves heat transfer in hybrid nano-liquid with platelet-shaped nanoparticles. • The coaxial cylinders can be employed as a central heat pipe for the PTSC's active thermal transport. [ABSTRACT FROM AUTHOR]

Solar thermal energy is a versatile and sustainable form of energy. It has vast applications and can be used to reduce fossil fuel consumption. The sun's heat harnesses this renewable energy; therefore, the energy transmission rate plays a significant role here. This article gives the idea of a new geometric design of solar thermal collector tubes for multiple uses and materials to be used on the tube's outer layer to maximize heat absorption. For this purpose, we investigated velocity, temperature, and heat transfer rates due to different nanoparticle (Cu/Al 2 O 3 /GO) combinations. We assumed the flow of Newtonian/non-Newtonian nanofluids flowing through the coaxial region of the cylindrical shape solar tubes. Here, water and seawater are considered for the Newtonian case, and sodium alginate is regarded for the non-Newtonian case. The governing equations of the flow are converted into ODEs with the help of similarity variables and solved numerically using the Keller box method. The MATLAB code for the Keller box method has been developed to plot graphical results. The primary outcomes are exhibited through graphs and tables. It is perceived that the temperature and heat transfer rates in Newtonian and non-Newtonian fluids are enhanced due to the trihybrid (Cu + Al 2 O 3 +GO) combination. This work can be utilized in an evacuated solar thermal system and gives the idea to develop a sustainable solar thermal system for multipurpose usage. • A sustainable solar thermal system model for multipurpose usage. • Simultaneous outcomes for Newtonian and non-Newtonian cases. • Al 2 O 3 +GO nanomaterial combination enhances the sun's heat absorption rate. • The heat absorption rate of evacuated solar heater tubes can be improved with a Cu + Al 2 O 3 +GO + sea water combination. [ABSTRACT FROM AUTHOR]

Theoretical analysis is performed to examine the heat convection in hydromagnetic Sutterby nanofluid flow across a cone in the attendance of Darcy-Forchheimer and modified temperature flux effects. The enhanced heat transmission was investigated using Maxwell and interfacial layer (nanolayer) approaches by considering ethylene glycol (EG) based spherical copper (Cu) nanoparticles. An exact model is developed and verified numerically using the bvp5c MATLAB scheme. Simultaneous outcomes are obtained for Maxwell and nanolayer approaches. Pertinent parameters influence on momentum and energy fields is examined via plots and tables. The nanolayer approach reported higher thermal conductivity than the Maxwell approach. Also, modified heat flux commendably improves the heat diffusion rate of Sutterby nanofluid without affecting the wall resistance. [ABSTRACT FROM AUTHOR]

The present report emphasizes on the thermo-physical feature of the radiative hydrodynamic stream of hybrid nanofluid above a nonlinearly extending surface with uneven heat sink or source effects. The equations yielded by mathematical modeling are accessed numerically by employing bvp5c MATLAB package. The uniqueness of the current scrutiny is to deliberate the simultaneous results of the radiative hydrodynamic flow along extending surface for nanofluid (ethylene glycol + CuO) and hybrid nanofluid (ethylene glycol + CuO + Al2O3) instances. Furthermore, the influences of sundry physical parameters on the flow and thermic gradients are graphed, and wall friction and heat transmission rate are illustrated via tables for nanofluid and hybrid nanofluid situations. The outcomes reveal that the energy transport rate in a hybrid nanofluid case is substantially larger than the nanofluid case. Moreover, the viscous dissipation parameter performs a major role in enriching the temperature gradient of the hybrid nanoliquid than the nanoliquid. The prime application of the present work can be found in industrial processing, where control over heat transport is required. [ABSTRACT FROM AUTHOR]

A numerical analysis is performed to scrutinize the heat transport of the Sutterby hybrid nanofluid flow between two concentric cylinders. This work incorporates ethylene glycol as a base liquid immersed with Al2O3 and TiO2 nanomaterials. A uniform magnetic field is employed in the existence of radiative heat, Ohmic heating, and in homogeneous heat production or absorption to investigate base fluid and hybrid nanofluids' motion and thermal transfer properties. The flow model is constructed and solved mathematically utilizing the Keller–Box method and MATLAB software. Comparable outcomes for base liquid and cross-nanoliquid are discovered and explained. The subject of the research work is the use of solar energy with parabolic trough solar collectors. It is discovered that the thermal transmission rate of hybrid nanofluid is more remarkable than base liquid. The magnetic field's drag force can control the flow and heat regions. [ABSTRACT FROM AUTHOR]

The present article emphasizes the bearing of radiative heat flux, Joule heating on the 3D magneto-flow of tangent hyperbolic mixed nanoliquid above a linear/nonlinear expandable surface. The aluminum alloy nanoparticles AA7072 and AA7075 are suspended in methanol liquid to obtain a hybrid nanofluid. The nonlinear partial differential equations are renovated to ordinary differential equations by utilizing appropriate similarity conversions, and further, the solutions are attained via the bvp5c MATLAB package. The novelty of this research is to supply simultaneous outcomes of the radiative hydrodynamic flow along linear and nonlinear extending surface situations. Further, the stimulus of sundry factors on the flow features is reflected with the aid of plots. The thermal transport rate in the nonlinear extending case is twice greater than the linear stretching case under the action of nanoparticles. Also, the existence of unique nanoparticles performs a substantial response in boosting the thermal transport mechanism of the non-Newtonian liquid. [ABSTRACT FROM AUTHOR]

The silver and gold nanoparticles display noteworthy results in antimicrobial and anticancer therapies. Silver is a considerable anti-inflammation, and gold nanoparticles effectively use to convert the photons to heat to destroy cancer cells. By keeping this in view, we investigated the radiative heat allocation in blood-based Ag-Au hybrid nanofluid flow. We assumed a blood vessel with cosine stenosis in the existence of an aligned magnetic field and variable heat source/sink. The flow model was developed to investigate the underlying physics and solved numerically after applying appropriate transformations. The computational outcomes for the flow and energy fields were explored through graphical and numerical illustrations. Also, the consequences of local Nusselt number and wall friction were discussed. The outcomes are validated and found to be in noble agreement. It is noticed that the inclined magnetic angle can control the drag force and heat transmission. Also, the Ag-Au combination effectively enhances the rate of heat transfer. This may help the effective conversion of photons to heat energy used in cancer therapies. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is one of the most widely used commodity plastic materials worldwide in terms of the production and its consumption. At commercial scale, PP is produced in various grades like homopolymer and copolymer (random and impact) by the polymerization of propylene and mixture of propylene-ethylene monomers using Ziegler–Natta catalysts and alkyl aluminum as co-catalysts. The present study deals with the colored lump formation of polypropylene random copolymer (PPCP) during storage at large scale and its probable route cause analysis for the lump formation. The lump samples were collected and characterized using FTIR, TGA, DSC and molecular weight determination and compared with pure PPCP. FTIR data show all the signature peaks of PPCP with additional > C=O stretching near 1720 cm−1 in colored lump sample, TG analysis revealed degradation of PPCP polymer and formation of volatile organic compounds in the temperature range 200–250 °C, the DSC analysis of the colored lump and pure PPCP showed that the melting peak was broader for colored lump of PPCP (i.e., PPCP_Y) which is an indicative that polymer molecules were having different chain length and the molecular weight analysis showed that the colored sample was having very low molecular weight with some bimodal character as compared to pure polymer. Based on these data and observations, the possible reason for the colored lump formation was also discussed. [ABSTRACT FROM AUTHOR]

Long-term multi-decadal scale variability of South Asian Summer Monsoon (SASM) is known to be associated with the Atlantic Multidecadal Oscillation (AMO) with positive phase associated with above-normal rainfall and vice-versa over SASM region. Analysis of the 120-year historical record suggests that the relationship between the AMO and the SASM has weakened in recent decades. Two possible reasons emerge from the analyses of observational datasets and model experiments. Enhanced Indian Ocean warming and weakened North Atlantic Subtropical High (NASH) are the prime factors weakening AMO-SASM association in the recent decades. Indian Ocean warming co-occurred during the recent AMO warm phase weakens the meridional temperature gradient, weakening the regional Hadley cell, large-scale monsoon circulation and precipitation. The suppressed convection triggers a Rossby wave which manifests as a cyclonic circulation over west central Asia weakening the Tibetan anticyclone. In addition, weakening of NASH weakens the Circum-Global Teleconnection (CGT) connecting AMO to the SASM, leading to weakening of AMO-SASM association. Projected warming of the Indian Ocean and Atlantic demands better understanding of the AMO-SASM teleconnection and their projected changes for assessing future changes in SASM in a warming world. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 pandemic has upended life throughout the globe. Appropriate emphasis has been placed on developing effective therapies and vaccines to curb the pandemic. While awaiting such countermeasures, mitigation efforts coupled with robust testing remain essential to controlling spread of the disease. In particular, serological testing plays a critical role in providing important diagnostic, prognostic, and therapeutic information. However, this information is only useful if the results can be accurately interpreted. This pandemic placed clinical testing laboratories and requesting physicians in a precarious position because we are actively learning about the disease and how to interpret serological results. Having developed robust assays to detect antibodies generated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and serving the hardest-hit areas within the New York City epicenter, we found 3 types of discordances in SARS-CoV-2 test results that challenge interpretation. Using representative clinical vignettes, these interpretation dilemmas are highlighted, along with suggested approaches to resolve such cases. [ABSTRACT FROM AUTHOR]

Chlorella vulgaris is known for its protein, growth factor, and nutritional constituents. Chlorella vulgaris was cultivated in a 1000-L outdoor open raceway pond with a maximum volumetric productivity of 130 mg L-1 day-1. The harvested biomass was dried through different methods, viz., sun drying (30 °C), oven drying (60 °C), lyophilization (−110 °C), drum drying (120 °C), and spray drying (100–150 °C). The effect of the drying method on proximate composition, pigments (chlorophyll, carotenoids), bioactive compounds (total phenolic content, flavonoid content), vitamin B12, antioxidant properties (ferric reducing antioxidant power, DPPH, and total antioxidant activity), and the color quality of C. vulgaris biomass was evaluated. Surface characterization by scanning electron microscopy (SEM) and functional group characterization through Fourier transform infrared spectroscopy were also performed. The biomass dried through lyophilization and sun drying retained maximum bioactive compounds and antioxidant activities. In contrast, drum drying resulted in a loss of nutrients, viz., protein (up to 44%), lipid (up to 41%), vitamin B12 (up to 40%), total phenolic content (> 50%), total flavonoid content (> 50%), and antioxidant activity (> 50%). Oven drying led to a loss of 30% in total flavonoid content and 17% in ferric reducing antioxidant power. SEM showed the destruction of cell wall integrity in the drum-dried sample and porous structure in the spray-dried sample. This study suggests that drying methods affect the nutrients and bioactive compounds of C. vulgaris biomass, and therefore a drying method should be selected carefully depending on the end use of the biomass. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes an improved "K" type seven‐level switched capacitor inverter topology. The proposed topology consists of eight active switches, one floating capacitor, and two dc‐link capacitors. The floating capacitors are charged and discharged in each half‐cycle to maintain the capacitor voltage with the same value of the input voltage. The floating capacitor voltage is self‐balanced, and the output voltage is 1.5 times higher than the input voltage. To prove the superiority of the proposed topology, it is compared with the existing seven‐level inverters in terms of maximum voltage stress on the switch and required the number of power components. The simulation and experimental validation are carried out for 1.6 kW, 50 Hz using a laboratory‐based setup with a switching frequency of 5 kHz. The results are discussed highlighting the performance of the proposed topology for the dynamic load variations at different modulation indices. Both simulation results and experimental results have good agreement in terms of voltage balancing of flying capacitor. [ABSTRACT FROM AUTHOR]

The 2-D MXene material has garnered immense attention in the multidisciplinary region due to its high surface area, excellent electrical conductivity, good biocompatibility, and tunable physicochemical properties. MXene nanoparticles can be utilized in thermal ablation to destroy unwanted tissues and tumors without invasive surgery. Therefore, this work investigates MXene (Ti3C2) embedded blood flow over a curved shape stretching artery. The mathematical model for hybrid blood flow is developed to see the thermal changes due to external pressure and diffusion. Furthermore, the flow model PDEs are equipped with Darcy-Forchheimer's condition, external magnetic force, thermal radiation, and heat source/sink. These PDEs are converted into a system of ODEs by a proper similarity conversion. The solution of governing equations are acquired numerically, the flow and thermal performance outputs are exhibited through pictorial and tabular representations. It is revealed that the thermal performance is enhanced due to sphere shaped MXene (Ti3C2) nanoparticles. The outcomes of this study can be utilized in photothermic therapy and other applications where heat transfer plays an essential role. [ABSTRACT FROM AUTHOR]

Transformerless inverters (TIs) are widespread in photovoltaic (PV) applications due to their low cost and high efficiency. However, TIs suffer due to leakage current as a consequence of PV parasitic capacitance, and high-frequency common-mode voltage, which has resulted in the emergence of several topological and control scheme modifications. In this article, a switched-capacitor (SC) based inverter capable of synthesizing a five-level voltage is proposed. In the devised structure, the negative pole of the dc bus is directly connected to the grid neutral, thereby resulting in zero leakage current. In addition, industrial standard half-bridge modules can be employed directly for implementing the proposed inverter without modifications, making it more practically feasible. The proposed topology has the capability of self-voltage balancing of SC, reactive power processing, and full dc-bus utilization as opposed to half-bridge topologies. The principle of operation and a simple logic-gate-based pulse generation scheme is presented in detail. Simulation and experimental results confirming the practical viability of the proposed topology are presented. Finally, the superior features and the merits of the proposed topology are shown through a detailed comparison against state-of-the-art topologies. [ABSTRACT FROM AUTHOR]

An experiment was conducted to know the variability among 22 maintainers on maldandi and milo source of male sterility in rabi sorghum along with four checks M 35-1, BJV-44, DJ6514 and PKV Kranti. The study revealed considerable amount of variability for all the characters studied. The genotypic and phenotypic coefficients of variation observed to be the highest for grain yield per-plant, the number of seeds per panicle and panicle weight. All the characters showed an arrow difference between PCV and GCV, indicating that the observed variability has been primarily due to genotypic differences with the least influence of environment. High heritability coupled with high genetic advance over mean was noticed for all the characters studied there by indicating that the selection would be effective in improvement of these characters as they are controlled by the additive genes. Based on mean performance the genotypes IS 14010 and IS 19445 were found significantly superior over the checks M35-1 and DJ6514. [ABSTRACT FROM AUTHOR]

Observational records and climate model projections reveal a considerable decline in the Atlantic Meridional Overturning Circulation (AMOC). Changes in the AMOC can have a significant impact on the global climate. Sustained warming due to increased greenhouse gas emissions is projected to weaken the AMOC, which in turn can lead to changes in the location of Inter-tropical convergence zone (ITCZ), oceanic and atmospheric large-scale circulation, tropical precipitation and regional monsoons. Using proxy records, observations and CMIP6 simulations of IITM Earth System Model (IITM-ESM), we investigate the changes in the AMOC and associated changes in the large-scale circulation and precipitation patterns over the South Asian monsoon region. Transient CO2 simulation and additional model sensitivity experiments with realistic surface heat and freshwater perturbation anomalies under the experimental protocol of Flux Anomaly Forcing Model Intercomparison Project (FAFMIP) performed with IITM-ESM reveal a decline in the strength of AMOC. The weakening of AMOC is associated with enhanced heat and freshwater forcing in the North Atlantic resulting in the reduction of northward oceanic heat transport and an enhanced northward atmospheric heat transport. Changes in AMOC lead to weakening of large-scale north–south temperature gradient and regional land-sea thermal gradient, which in turn weaken the regional Hadley circulation and, monsoon circulation over the South Asian region. Both the FAFMIP and transient CO2 experiments reveal consistent results of weakening South Asian Monsoon circulation with a decline of AMOC, while precipitation exhibits contrasting responses as precipitation changes are dominated by the thermodynamic response. The suite of observational and numerical analysis provides a mechanistic hypothesis for the weakening of South Asian monsoon circulation concomitant with a weakening of AMOC in a warming climate. [ABSTRACT FROM AUTHOR]

Ferrofluids are the colloidal suspensions of magnetic nanoparticles and base fluids. It has several medical applications like drug targeting, cell separation, magnetic resonance imaging, etc. The dispersion of more than one magnetic nanoparticle into the convectional fluid is called hybrid nanofluid. It has various technological applications like damping, dynamic sealing, heat dissipation, etc. Due to the immense applications of the ferrofluids, in this analysis, we examined the liquid film flow and heat transfer of hybrid ferrofluid in the attendance of radiation and irregular heat source/sink. We considered the magnetite (Fe3O4) and cobalt ferrite (CoFe2O4) nanoparticles and suspended them into water–ethylene glycol (EG) mixture (50–50%). A mathematical model is developed for the present investigation and solved numerically after applying the suitable similarity transformations. The impact of various governing non-dimensional parameters on the momentum, energy fields, and local Nusselt number of ferro- and hybrid ferrofluids is studied with the aid of graphical illustrations. It is perceived that the rate of heat transfer is higher in hybrid ferrofluid than that of ferrofluid. [ABSTRACT FROM AUTHOR]

This letter describes a novel nine-level inverter based on switched capacitors (SCs) with quadruple-boost ability requiring reduced components. The structure of the proposed topology relies on the series/parallel connection of SCs. It consists of 12 switches and two SCs. As opposed to similar SC-based inverters, the proposed topology does not employ a back-end H-bridge and the voltage stress of all the switches does not exceed twice the input dc voltage. A simple logic-gate-based pulsewidth-modulation scheme is developed for gating the switches of the proposed topology. A comprehensive comparison against the state-of-the-art topologies in terms of the required number of components is performed to attest the outperforming merits of the proposed topology. Finally, various experimental results are presented to validate the feasibility and operability of the proposed topology. [ABSTRACT FROM AUTHOR]

Xylitol, a sugar alcohol is a low-calorie sweetener has wide applications in food and pharmaceutical industry and hence considered as a high value premium product. The conventional methods for fermentative xylitol production uses chemicals (acid/alkali) which generates inhibitors affecting fermentation and downstream purification of xylitol. In the present study, wet air oxidation was evaluated as a chemical-free pretreatment option of wheat bran for xylose release which is subsequently fermented to xylitol. Life cycle assessment was used as a tool to compare wet air oxidation with conventional methods like dilute acid pretreatment for valorization of wheat bran, a model agro-industrial remnant. A comparative evaluation of wet air oxidation and dilute acid pretreatment was investigated for fermentative production of xylitol (1 g/L as functional unit) with the aim of identifying the process involved with the lowest environmental impact, while also demonstrating the higher xylose recovery of 13.52 g/L coupled with FO based concentration unit. The inputs and outputs of the process involving energy use, chemicals employed, and emissions produced were evaluated with respect to food and environment perspective. Environmental impacts of wet air oxidation and dilute acid pretreatment with fermentative xylitol production of 6.134 and 1.42 g/L, respectively showed emission results of 1.476 and 5.288 kg CO 2 equivalent, respectively. Though, primary energy demand of wet air oxidation was almost found to be equivalent to dilute acid, due to energy penalty for reactor mixing was higher in wet air oxidation. However, energy demand of wet air oxidation-based pretreatment was found to be energy efficient by 30% as compared to dilute acid. Coupling biogas reduces energy demand by 3.5%. The reduction in impacts relevant to food safety namely, marine aquatic and freshwater ecotoxicity potential were found by 74.29% and 84.97% substantially lower in wet air oxidation as compared to dilute acid based xylitol production. The effect of sulphate, as input form of sulphuric acid in dilute acid showed an impact of 3.83 folds higher on human toxicity potential as compared to wet air oxidation pretreatment process. [Display omitted] [ABSTRACT FROM AUTHOR]

Two-Stage boosting multilevel inverters (MLIs), which are highly suitable for photovoltaic power plants, are known to suffer because of the high voltage stress on the switches of second stage. One of the ways to confront this issue is through eliminating the front-end booster. However, this leads to increased structural and control complexity of the resulting integrated boosting MLI. This letter presents a single-stage boosting MLI requiring lesser number of switches, diodes, and capacitors for renewable power generation applications. It requires nine switches and only one capacitor for five-level voltage generation. The topology has inherent self-balancing capability, thereby does not need additional balancing circuitry. The proposed topology has a uniform peak inverse voltage stress on the switches of value equal to the input dc voltage. A less complicated logic-form-equations-based gating pulse generation scheme is designed for enabling the proposed MLI to maintain its capacitor voltage. Further, a comparative study with state-of-the-art topologies is carried out to demonstrate the superior performance of the proposed topology. Finally, the feasibility of the proposed topology is validated through experimental tests and the corresponding results are elucidated. [ABSTRACT FROM AUTHOR]

This paper presents a nine-level transformer-based inverter requiring only eight switches. The envisaged structure consists of two standard H-bridges fed from a single dc source. Besides, a single-phase transformer is employed to aid the process of intermediate voltage level generation. An ad-hoc pulsewidth modulation scheme based on boolean logic form equations is developed to derive the gating pulses. An effortless extension of the proposed inverter to a higher number of voltage levels is also achieved by generalizing the switching functions. Furthermore, the superior performance of the proposed topology is demonstrated through a comprehensive cost-based analysis. Finally, the validation of the proposed topology is accomplished through experiments on a down-scale prototype, and the measurement results are included. [ABSTRACT FROM AUTHOR]

The flow of magnetohydrodynamic Carreau liquid with the Brownian moment, thermophoresis and cross diffusion effects is investigated numerically. The buoyancy persuades on the flow is contemplated in such a way that the surface is neither perpendicular/horizontal nor wedge/cone. This is very helpful in the design of jet-engine. The equations govern the flow are transmuted using acceptable similarity variables and numerically solved by recruiting Runge-Kutta based Newtons method. The graphical results are obtained to discuss the stimulus of flow, thermal and concentration fields for different parameters of interest. The wall friction, local Nusselt and Sherwood numbers are examined with the assistance of tables. It is noticed that the parabolic flow is controlled by the buoyant forces developed by the temperature difference. Since the flow is laminar, the Reynolds number considered as <1000. This study has applicable in man-made products and various industries like pumps and oil purification, petroleum production, power engineering and chemical engineering processes. [ABSTRACT FROM AUTHOR]

This letter presents an improved sensorless nine-level inverter topology with reduced number of components. It is formed by cascading a three-level T-type neutral clamped point inverter with a floating capacitor (FC) fed two-level converter unit. Additionally, two line-frequency switches are appended across the dc-link. A simple logic-form equations-based pulse width modulator is designed which is in-charge of maintaining the FC voltage at its reference value without any aid of voltage and current sensor. Thus, the complexity in control of the proposed topology is very minimal. The working principle of the proposed inverter and formulation of logic-form equations is deliberated in detail. Furthermore, experimental results obtained from the developed prototype are presented to validate feasibility and operability of the proposed topology. Finally, a comprehensive comparison with some of the recently reported inverter topologies proving the merits of the proposed topology is included. [ABSTRACT FROM PUBLISHER]

This paper presents a nine-level active-neutral-point-clamped (ANPC) based multilevel inverter (MLI) topology for grid-connected applications requiring only ten switches. The envisaged structure comprises two parts, namely five-level ANPC unit, and a two-level converter leg whose midpoint is used as another ac terminal. An ad hoc switching state redundancy based modulation strategy is used to ensure that the voltage across the flying capacitor is tightly balanced and is implemented using a look-up table further simplifies the control complexity. The performance and effectiveness of the proposed topology with its control scheme are validated through simulations and experimental tests. Comparison with other MLIs is included to highlight the merits of the proposed topology. From the results, it will be shown that the proposed inverter requires the least part count as compared to other topologies with the same performance and output quality. [ABSTRACT FROM PUBLISHER]

Abstract: The novel derivatives of morpholine-clubbed 3-substituted coumarinyl acetamide and cinnamide derivatives 5a-5j and 6a-6j have been synthesized via various 2-chloro-N-phenyl acetamide and cinnamoyl chloride derivatives, respectively. The required motif has been generated through Vilsmeier-Haack reaction on 4-hydroxycoumarin annelation of morpholine followed by imine formation and subsequently condensation with various 2-chloro-N-phenylacetamide and cinnamoyl chloride to furnish the desired molecule. The synthesized molecules were characterized by various spectroscopic methods viz IR, 1H NMR, 13C NMR. Their antimicrobial activities against various strains of bacteria and fungi have been evaluated, and computational studies have also been performed for all the newly synthesized analogs. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Considering the recent aspiration of experts dealing with the painting of aircraft and bonnet of cars to further understand the relevance of skin friction and heat transfer while painting all these objects that are neither horizontal nor vertical, neither a cone/wedge or cylinder but upper horizontal surface of a paraboloid of revolution; a two-dimensional electrically conducting Casson fluid flow on an upper horizontal thermally stratified surface of a paraboloid of revolution is analyzed. The influence of melting heat transfer and thermal stratification are properly accounted for by modifying classical boundary condition of temperature. Plastic dynamic viscosity and thermal conductivity of the fluid are assumed to vary linearly with temperature. In view of this, all necessary models were modified to suit the case T m < T ∞ $T_m

Copper imparts better organoleptic properties to cheese, while cheese acts as a vehicle for probiotic cultures. These studies revealed that copper stress changed key probiotic properties like acid and bile salt tolerance of a model organism Lactobacillus helveticus CD6. After growing the culture in copper stress, the acid tolerance at pH 2 was lost along with a decrease in bile salt tolerance by 15%, while other desiring properties like auto‐aggregation, cell surface hydrophobicity and antibacterial activity were improved. This study suggests that copper tolerant culture with retained probiotic properties could be used to deliver through cheese to the consumers. [ABSTRACT FROM AUTHOR]

This paper proposes a new nine-level inverter for medium- and high-power applications. The proposed topology comprises of a three-level (3L) active neutral-point-clamped (ANPC) inverter connected in series with a floating capacitor (FC) fed H-bridge. Besides, two additional switches operating at line frequency are appended across the dc link of the 3L ANPC structure. Compared with conventional hybrid cascaded inverters, the primary advantage of this addition is doubling of the resulting root mean square output voltage. This amelioration is achieved while preserving the standard 3L ANPC and H-bridge structures with minimum topological modification. A simple logic-gate-based voltage balancing scheme is developed to regulate the FC voltage. The proposed voltage balancing method is independent of load power factor, inverter modulation index, and can balance the voltage across FC instantaneously. The step-by-step formulation of logical expressions for the generation of gating pulses is deliberated in detail and can be generalized for any $n$-level inverter. Further, simulation results as well as the experimental measurements obtained from the laboratory prototype are presented to validate the effectiveness and practicability of the proposed configuration. Finally, the notable merits of the proposed inverter over the prior art topologies is established through a comprehensive comparative study. [ABSTRACT FROM PUBLISHER]

Background: Mandibular incisors are the smallest among the permanent dentition, with thin enamel and dentin. Intact teeth do not fracture easily while mastication. Objectives: To evaluate the fracture resistance of mandibular incisors after endodontic treatment and metal ceramic crown placement. Materials and methods: Eighty recently extracted intact mandibular incisors were divided into four groups of twenty each based on root canal treatment and crowns, intact natural tooth without RCT and crown preparation was used as control group. Each tooth was mounted separately in acrylic block and subjected to loading in universal load testing machine until fracture, results were analyzed by one-way ANOVA and Turkey’s multiple post hoc procedures. Results: The results showed that Fracture resistance of teeth restored with metal ceramic crowns was very high when compared to the teeth without crowns (p<0.05).There was no statistically significant difference between intact and endodontically treated teeth (p>0.05). Conclusion: The study concluded that endodontic treatment and tooth preparation followed by metal ceramic restoration increased the fracture resistance of mandibular incisors. [ABSTRACT FROM AUTHOR]

An ambitious project connecting Jammu and Srinagar through a railway link in tectonically active and geologically complex Himalayan Mountain terrain is under progress. Under this project, the world's highest (359 m) railway arch-bridge is under construction across the River Chenab in the northern territory of India. This mega engineering structure has a two-fold ribbed arch design, comprising of steel girders. During the excavation for one of the concrete pillars on the right abutment, wide open joints and weak/shear zones were noticed. The width of these joints varies from 30 to 50 cm, trending along N170 ° with a dip of 65 ° . The foundation area of this pillar is 13 m × 24 m and on the cut slopes of the right bank of Chenab River. These exposed joints and weak zones were treated with consolidation grouting to strengthen the foundation area. To delineate the extent of these joints and weak zones below the foundation level, seismic tomography was carried out in five boreholes drilled for this purpose to cover the 300 sq-m area. The results of cross-hole seismic tomography reveals the presence of three low velocity (≤ 2600 m/s) anomalous zones below the foundation area. This also ascertained the efficacy of grouting in consolidating the joints and weak zones. Later, rock-mass quality (Q) was determined based on the relationship between the P-wave velocity and the Q-value (Barton, 2002) to infer the support system for the slope stabilization below the foundation. 3-D visualization of the seismic velocity demarcates the extent of weak or untreated zones. This methodology facilitates to update the design parameters according to Q-values during the construction stage and estimate the required level of reinforcement and support system. Similar methodology can be applicable in other areas under same site conditions. [ABSTRACT FROM AUTHOR]

This letter proposes a single-phase nine-level (9L) inverter topology suitable for grid-connected renewable energy systems. The proposed inverter is realized using a T-type neutral-point-clamped inverter connected in cascade to a floating capacitor (FC) H-bridge. Additionally, two low-frequency switches are added across the dc-link enabling the inverter to generate a 9L waveform. A sensorless voltage control based on redundant switching state is developed and embedded with PWM controller, which is responsible for regulating the FC voltage at one-quarter of the dc source voltage. The proposed PWM technique employs the generation of 9L waveform without using any voltage sensor, thereby reducing the complexity of the overall control scheme. This, in turn, will make the overall system appealing for various industrial applications. In comparison to conventional and recent topologies, generation of the 9L waveform using a lower number of components is the notable contribution. Another important feature of the proposed inverter is that if FC H-bridge fails, it can be bypassed, and the inverter can still operate as a 5L inverter at its nominal power rating. Furthermore, a comprehensive comparison study is included which confirms the merits of the proposed inverter against those of other state-of-the-art topologies. Finally, simulation and experimental results are included for validating the feasibility of the proposed system. [ABSTRACT FROM PUBLISHER]

Laminar flow past a rotating cylinder near a plane wall is studied numerically using a second-order accurate immersed boundary method. The wake-wall interactions are investigated in detail, for different wall heights and varying rotational rates. Flow patterns are classified based on the wake structure and the effect of rotation on critical wall heights is discussed for both clockwise and counterclockwise rotation. For the configuration studied i.e. rotating cylinder above a bottom plane wall, counterclockwise rotation of cylinder favors the wake-wall interactions, while clockwise rotation influences in an adverse manner. In addition to conventional analysis, the evolution of the vortical structures in the wake region are examined using Lagrangian analysis of individual vortical structures. The diffusion of the positive vortex shed from the wall facing side of the cylinder is accelerated due to the influence of boundary layer with net negative vorticity. The wall augmented diffusion of positive cylinder vortices is compensated by the creation of secondary wall vortices from the bottom wall boundary layer. Counterclockwise rotation of cylinder increases the shear inside boundary layer resulting in more pronounced diffusion. [ABSTRACT FROM AUTHOR]

Extrinsic magnetic fields are capable to set the thermal and physical properties of magnetic-nanofluids and regulate the flow and heat transfer characteristics. Applied magnetic field affects the thermal conductivity of magnetic-nanofluids and makes it aeolotropic. With this incentive, we investigate the flow and heat transfer characteristics of liquid film flow of magnetic-nanofluids over the vicinity of a thin elastic sheet by considering the transverse magnetic field with variable heat source/sink. We consider water as a base fluid embedded with the two different types of aluminum alloy nano/particles namely AA 7072 and AA 7075. AA 7072 is a special type of heat treatable aluminum alloy with 98% Al and 1% of Zn with the additives such as Si, Fe and Cu etc. Similarly, AA 7075 contains 90% Al, 5–6% Zn, 2–3% Mg, 1–2% Cu with the additives as Si, Fe and Mn etc. The transformed governing partial differential equations are solved numerically using R-K based shooting technique. The diagrammatic and tabular results depict the effect of pertinent parameters on common profiles of interest. It is found that the heat transfer rate of water-AA 7075 is significantly high when compared with the heat transfer rate of water-AA 7072. It is also found that the increasing percentage of Cu leads to enhance the heat transfer rate. [ABSTRACT FROM AUTHOR]

Heat and mass transfer nature of magnetohydrodynamic Williamson and Casson fluids towards an upper paraboloid of revolution with thermophoresis and Brownian moment is discussed theoretically. Thermo-diffusion and diffusion-thermo effects are incorporated in the model. The governing equations of the flow is transformed using fitting similarity variables and solved by employing R-K based shooting technique. The behaviour of flow, temperature and concentration fields for different physical aspects is discussed through graphical illustrations. Also computed the coefficient of skin friction, local Nusselt and Sherwood numbers and presented through tables. It is found that the heat and mass transfer performance of Casson fluid is comparatively higher than that of Williamson fluid. [ABSTRACT FROM AUTHOR]

In this article, we analyzed the upper convected Maxwell fluid (UCM) flow across a horizontal melting surface in the presence of cross-diffusion and double stratification (thermal and solutal) effects. We reconstructed the controlling equations as a group of nonlinear ordinary differential equations and then resolved by enforcing Runge-Kutta method with shooting technique. The influence of important parameters on the three common profiles (velocity, temperature, and concentration) is discussed through plots. Tables are utilized to discuss the wall friction, heat and mass transfer rates of both Newtonian and UCM flows. We witnessed that the thermal stratification, Soret number, Schmidt number and temperature dependent viscous parameter improve heat transfer rate. Setting the two flows side by side, it is worthy to mention that the temperature and concentration profiles looking high in the Newtonian fluid flow. [ABSTRACT FROM AUTHOR]

A Mathematical model is developed for investigating the heat and mass transfer of magnetohydrodynamic Casson fluid over a moving wedge with slip, nonlinear thermal radiation, uniform heat source/sink and chemical reaction. For regulating the momentum and concentration gradients we also considered the viscous dissipation and cross diffusion effects. Numerical solutions are carried out by employing Runge-Kutta and Newton's methods. The effects of the physical governing factors on the flow, temperature and concentration profiles are illustrated graphically for accelerating and decelerating flow cases. We also computed the local Nusselt and Sherwood numbers along with friction factor for the same cases. It is found that increasing the temperature jump parameter encourages the heat transfer rate. It is also concluded that the local Nusselt number is high in accelerating flow case when equated with the decelerating flow case. [ABSTRACT FROM AUTHOR]

Nowadays graphene is emanating as one of the most encouraging nanomaterial due to its continuous electrical conducting behaviour even at zero carrier concentration. With this initiation, we investigate the flow and heat transfer nature of liquid film flow of magnetic-nanofluids over a stretching surface by considering the aligned magnetic field with non-uniform source/sink and thermal radiation. For this study, we considered the graphene (GP) nanoparticles embedded in water and water-ethylene glycol (EG) mixtures (i.e. 70%water + 30%EG and 50%water + 50%EG). With the assistance of similarity transformations, governed equations are transferred as ordinary differential equations. Numerical results are determined by applying the Runge-Kutta and Newton’s methods. Graphs are exhibited and explained for important parameters. The influence of non-dimensional parameters on reduced Nusselt number, flow and heat transfer is discussed with the assistance of graphs. It is found that aligned magnetic field regulates the local Nusselt number. It is also found that rising the volume fraction of nanoparticles effectively boosts the thermal conductivity of water + 50%EG + GP nanofluid when compared with water + GP and water + 30%EG + GP nanofluids. [ABSTRACT FROM AUTHOR]

In this study, we investigated the momentum and heat transfer characteristics of Casson nanofluid flow over a rotating cone in a rotating frame filled with water based CoFe 2 O 4 nano particles. Heat flux conditions and wall temperature conditions are very important in controlling of up and down heat transport phenomena's in industrial as well as engineering application. Resulting set of coupled nonlinear governing equations are solved numerically using Runge–Kutta based shooting technique. In graphical results we presented dual solutions for the prescribed wall temperature (PWT) and prescribed heat flux (PHF) cases. The effect of governing parameters on velocity and temperature fields along with the skin friction coefficient and the heat transfer rate are presented with the help of graphs and tables. Results indicate that the rising values of the volume fraction of ferro particles and buoyancy parameter have tendency to improve the skin friction coefficient as well as the heat transfer rate for both the prescribed wall temperature (PWT) and prescribed heat flux (PHF) cases. [ABSTRACT FROM AUTHOR]

With every passing day, heat transfer enhancement in convectional base fluids plays a major role in several industrial and engineering processes. During this process, nanofluids attained great importance to enhance the heat transfer rate in convectional flows. Keeping this into view, in this study, we analyzed the MHD flow and heat transfer characteristics of a dusty nanofluid over a stretching surface in the presence of a volume fraction of dust and nano-particles. We have considered two types of nanofluids; namely, CuO-water and Al2O3-water immersed with dust particles. The governing partial differential equations are transformed into a set of nonlinear ordinary differential equations by using similarity transformation, which are then solved numerically using Runge-Kutta based shooting technique. We found an excellent agreement of the present results with the existing literature. The effects of non-dimensional governing parameters; namely, magnetic field, volume fraction of dust particles, volume fraction of nano-particles, porosity, mass concentration of dust particles and fluid particle interaction on velocity and temperature profiles for both fluid and dust phases are discussed and presented through graphs. Also, skin friction coefficient and local Nusselt number are discussed and presented in tabular form. [ABSTRACT FROM AUTHOR]

The knowledge of heat transfer of MHD nanofluid flows over different geometries is very important for heat exchangers design, transpiration, fiber coating, etc. With this initiation, mathematical model is developed to investigate the heat transfer nature of electrically conducting magnetohydrodynamic nanofluid flow over a cone and a wedge. For this investigation, we consider a nonlinear thermal radiation, viscous dissipation, Joule heating with non-uniform heat source/sink effects. Water considered as the base fluid and suspended with copper nanoparticles. R-K and Newton's methods are employed to resolve the altered governing nonlinear equations. Effects of pertinent parameters of concern on the common profiles are conversed (in two cases). It is observed that the momentum and temperature boundary layers are non-uniform for the flow over three a wedge and a cone. Rising the viscous dissipation strengths the velocity and temperature fields. [ABSTRACT FROM AUTHOR]

Numerical solutions are presented for fluid flow past a rotating elliptic cylinder for different non-dimensional rotational rates (0.5, 1.0 and 1.5) and various axis ratios (0.1, 0.3, 0.5, 0.7 and 1.0). The two-dimensional, incompressible Navier–Stokes equations are solved using Immersed Boundary method on a non-body conforming Cartesian grid. Reynolds number based on the perimeter of the elliptic cylinder is 100. Periodic flow after an impulsive start of the elliptic cylinder is studied. Flow patterns and variation of aerodynamic force coefficients are reported for different set of parameters and it is observed to be very different from that of rotating circular cylinder. As the cylinder rotates, the trailing edge of the cylinder aids the flow while the leading edge deters the flow. This has significant effect on the wake region and vortex shedding pattern. Complex interactions between cylinder and shed vortices result in many interesting phenomenon, such as formation of hovering vortex. Parameters affecting the formation of hovering vortex and its underlying mechanism are analyzed. Aerodynamic force coefficients and vortex shedding frequencies are presented and it is observed that force coefficients have multiple amplitudes and frequencies. [ABSTRACT FROM AUTHOR]

Reliance on volunteer blood donors can lead to transfusion product shortages, and current liquid storage of red blood cells (RBCs) is associated with biochemical changes over time, known as ‘the storage lesion’. Thus, there is a need for alternative sources of transfusable RBCs to supplement conventional blood donations. Extracorporeal production of stem cell-derived RBCs (stemRBCs) is a potential and yet untapped source of fresh, transfusable RBCs. A number of groups have attempted RBC differentiation from CD34+ cells. However, it is still unclear whether these stemRBCs could eventually be effective substitutes for traditional RBCs due to potential differences in oxygen carrying capacity, viability, deformability, and other critical parameters. We have generated ex vivo stemRBCs from primary human cord blood CD34+ cells and compared them to donor-derived RBCs based on a number of in vitro parameters. In vivo, we assessed stemRBC circulation kinetics in an animal model of transfusion and oxygen delivery in a mouse model of exercise performance. Our novel, chronically anemic, SCID mouse model can evaluate the potential of stemRBCs to deliver oxygen to tissues (muscle) under resting and exercise-induced hypoxic conditions. Based on our data, stem cell-derived RBCs have a similar biochemical profile compared to donor-derived RBCs. While certain key differences remain between donor-derived RBCs and stemRBCs, the ability of stemRBCs to deliver oxygen in a living organism provides support for further development as a transfusion product. [ABSTRACT FROM AUTHOR]

Nanofluids are potential heat transfer fluids with enhanced thermal and physical properties can be applied in many areas. External magnetic field have tendency to set the thermal and physical properties of nanofluids. With this motivation, we investigated the effects of temperature dependent viscosity, heat source/sink and viscous dissipation on natural convective heat transfer of radiative magnetohydrodynamic (MHD) non-Newtonian nanofluid caused by a cone. For this study, a simulation is performed by mixing of copper nanoparticles in the kerosene. The self similar transformed governing equations are solved by enforcing Runge-Kutta based shooting technique. We acquire the significant accuracy of the recent results by comparing with the published results. In addition, it is indicated that the dual solutions exist for both the base fluid and nanofluid cases. The effects of dimensionless parameters including Eckert number, Weissenberg number, Power-law index, viscous variation parameter, heat source/sink, thermal radiation parameter, and magnetic field parameter on velocity and temperature fields along with the friction factor coefficient and the local Nusselt number are discussed with the help of graphs and tables. It is shown that nanoparticles inclusion into the non-Newtonian fluids has a positive effect on thermal performance. In addition, the viscous variation parameter has a tendency to encourage the friction factor coefficient as well as the heat transfer rate. Moreover, Cu-kerosene nanofluid signifies a better thermal performance than the Ag-kerosene nanofluid. [ABSTRACT FROM AUTHOR]

Recent days, graphene is emanating as one of the most encouraging nanomaterials due to its continuous electrical conducting behaviour even at zero carrier concentrations. Heat transfer in non-Newtonian fluids plays a major role in technology and in nature due to its stress relaxation, shear thinning and thickening properties. With this incentive, we investigate the flow and heat transfer characteristics of electrically conducting liquid film flow of water based non-Newtonian nanofluids dispensed with graphene nanoparticles. For this investigation, we proposed a mathematical model for the flow of Jeffrey, Maxwell and Oldroyd-B nanofluids past a stretching surface in the presence of transverse magnetic field and non-uniform heat source/sink. Numerical results are carried out by employing Runge-Kutta-Felhberg integration scheme. The influence of pertinent parameters on reduced Nusselt number, friction factor, flow and heat transfer is discussed with the assistance of graphs. Embedding the graphene nanoparticles effectively enhances the thermal conductivity of Jeffrey nanofluid when compared with the Oldroyd-B and Maxwell nanofluids. Deborah number in terms of relaxation time plays a major role in convective heat transfer. [ABSTRACT FROM AUTHOR]

The motion of nanofluid (water and 36 nm alumina nanoparticles) along upper horizontal surface of a paraboloid of revolution in the presence of nonlinear thermal radiation, Lorentz force and space dependent internal heat source within thin boundary layer is investigated theoretically. It is assumed that buoyancy induces the flow over this kind of surface which is neither a horizontal/vertical nor cone/wedge, hence suitable buoyancy model for this case of fluid flow is presented. The viscosity and thermal conductivity are assumed to vary with volume fraction and suitable models for the case 0 % ≤ ϕ ≤ 0.8% are adopted. The transformed governing equations are solved numerically using Runge-Kutta fourth order along with shooting technique (RK4SM). Good agreement is obtained between the solutions of RK4SM and MATLAB bvp5c for limiting case. The influence of pertinent parameters are illustrated graphically and discussed. It is found that temperature and velocity functions are maximum at higher values of internal space dependent heat source. Local heat transfer rate is maximum at smaller values of internal space dependent heat source. [ABSTRACT FROM AUTHOR]