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Efficient and highly functional three-dimensional systems that are ubiquitous in biology suggest that similar design architectures could be useful in electronic and optoelectronic technologies, extending their levels of functionality beyond those achievable with traditional, planar two-dimensional platforms. Complex three-dimensional structures inspired by origami, kirigami have promise as routes for two-dimensional to three-dimensional transformation, but current examples lack the necessary combination of functional materials, mechanics designs, system-level architectures, and integration capabilities for practical devices with unique operational features. Here, we show that two-dimensional semiconductor/semi-metal materials can play critical roles in this context, through demonstrations of complex, mechanically assembled three-dimensional systems for light-imaging capabilities that can encompass measurements of the direction, intensity and angular divergence properties of incident light. Specifically, the mechanics of graphene and MoS2, together with strategically configured supporting polymer films, can yield arrays of photodetectors in distinct, engineered three-dimensional geometries, including octagonal prisms, octagonal prismoids, and hemispherical domes.

A study has been carried for a viscous, incompressible electrically conducting MHD blood flow with temperature-dependent thermal conductivity and viscosity through a stretching surface in the presence of thermal radiation, viscous dissipation, and chemical reaction. The flow is subjected to a uniform transverse magnetic field normal to the flow. The governing coupled partial differential equations are converted into a set of non-linear ordinary differential equations (ODE) using similarity analysis. The resultant non-linear coupled ordinary differential equations are solved numerically using the boundary value problem solver (bvp4c) in MATLAB with a convincible accuracy. The effects of the physical parameters such as viscosity parameter (μ(T˜b))\left({\mu ({{\tilde T}_b})} \right) , permeability parameter (β), magnetic field parameter (M), Local Grashof number (Gr) for thermal diffusion, Local modified Grashof number for mass diffusion (Gm), the Eckert number (Ec), the thermal conductivity parameter (K(T˜b))\left({K({{\tilde T}_b})} \right) on the velocity, temperature, concentration profiles, skin-friction coefficient, Nusselt number, and Sherwood number are presented graphically. The physical visualization of flow parameters that appeared in the problem is discussed with the help of various graphs to convey the real life application in industrial and engineering processes. A comparison has been made with previously published work and present study revels the good agreement with the published work. This study will be helpful in the clinical healing of pathological situations accompanied by accelerated circulation.

This study investigates the impact of variable permeability as well as chemical reactions on the oscillatory free convective flow that passes parallel porous flat plates with fluctuating temperature and concentration in the presence of a magnetic field. A vertical channel is assumed to be rotating at an angular velocity Ω. Periodic free stream velocity causes oscillations in one plate, while periodic suction velocity causes oscillations in the other plate. Complex variable notations are used to solve the governing equations. The perturbation technique is used to derive analytical expressions for the temperature, concentration, and velocity fields. In this study, various parameters were investigated in relation to mean velocity, mean temperature, mean concentration, amplitude, and phase difference. The study also examines the impact on secondary velocity, primary velocity, temperature, concentration, and heat transfer rate during transients. The outcomes are presented graphically for the physical parameters of the problem. The findings contribute to optimizing systems and improving efficiency in heat transfer, fluid dynamics, and environmental remediation. [ABSTRACT FROM AUTHOR]

The present study explores the dynamics of a two-dimensional, incompressible nanofluid flow through a stretching curved sheet within a highly porous medium. The mathematical model is formulated by including external forces such as viscous dissipation, thermal radiation, Ohmic heating, chemical reactions, and activation energy by utilizing a curvilinear coordinate system. The viscosity and thermal conductivity of the nanofluids are examined using the Koo–Kleinstreuer–Li model. The choice of |$Al_{2}O_{3}$| and |$CuO$| nanoparticles in this model stems from their distinct thermal properties and widespread industrial applicability. By non-dimensionalizing the governing partial differential equations, the physical model is simplified into ordinary differential equations. BVP-5C solver in MATLAB is utilized to numerically solve the obtained coupled non-linear ordinary differential equation. Graphical results are presented to investigate the velocity, temperature, and concentration profiles with entropy generation optimization under the influence of several flow parameters. The artificial neural network backpropagated with Levenberg–Marquardt method (ANN-BLMM) used to study the model. The performance is validated using regression analysis, mean square error and error histogram plots. The outcome illustrates that the velocity and temperature profiles increase with increasing the Forchhiemer parameter. Also, the velocity profile increases with increasing curvature parameter, while, reverse effect is observed for temperature profile. This research augments our comprehension of nanofluid dynamics over curved surfaces, which has implications for engineering applications. The insights gained have the potential to significantly contribute to the advancement of energy-efficient and environmentally sustainable cooling systems in industrial processes. [ABSTRACT FROM AUTHOR]

The investigation of blood flow into curved arteries is fascinating and essential to prevent the advancement of vascular disease. Motivated by electro-kinetic manipulation, gold nanoparticles, and their size applications, a mathematical model is developed to explain blood flow, entropy generation, and electro-kinetic energy conversion (EKEC) efficiency in curved arterial flow. To make this study more realistic, a patient-specific overlapped stenosis condition and non-Newtonian (power-law fluid) blood flow model have been considered. The effects of a magnetic field, external heating, and chemical reactions are also included. The Stone's strongly implicit scheme has been considered to solve the system of non-linear partial differential equations (PDE's) in the" MATLAB" software. In this numerical investigation, an error tolerance of 10 − 6 has been considered for every iteration step under Stone's scheme. The significance of various physical parameters, such as nanoparticle volume fraction (m), their size (dp), magnetic field intensity (M), inverse Debye length ( κ ¯ ), flow behavior index (Sc), heat source (H), and chemical reaction parameter (ξ) on the blood flow velocity, temperature, concentration, EKEC efficiency, and entropy generation have been explained graphically. This study also developed stream function contours to describe flow trapping patterns. The findings of this study conclude that the blood flow EKEC efficiency reduces with the presence of nanoparticles and stenosis in the artery. In addition, both flow velocity and entropy enhance by adopting large-size nanoparticles instead of small diametric nanoparticles. Clinical researchers and biologists may use the results of this computational study to forecast endothelial cell damage and plaque deposition in curved arteries with WSS profiles, by which the severity of these conditions can be reduced. [ABSTRACT FROM AUTHOR]

A novel mathematical model for a hybrid (Cu–CuO/blood) Jeffrey nanofluid passing a vertical symmetric microchannel along with an electroosmosis pump is presented. The focuses on the advancement of mathematical modeling techniques, its comprehensive analysis of microfluidic system dynamics, and its potential to inform the optimal design of devices using nanofluids with broad applications in various fields. Arrhenius’s law is used to analyze endothermic– exothermic reactions and activation energy. The governing partial differential equations of the fixed frame are transformed into ordinary differential equations of the wave frame using self-similarity transformations. Low Reynolds number and long-wavelength approximations helped to find solutions of the equations by applying a suitable BVP solver in MATLAB. The fluid’s velocity, temperature, concentration, and electroosmosis properties are studied graphically. Two-dimensional contour plots of fluid velocity and three-dimensional surface plots of fluid properties are discussed. Physically significant quantities of mass transfer rate, skin friction coefficient, entropy generation, and heat transfer rate are studied using contour plots. Artificial neural network simulation using Bayesian regularization backpropagation algorithms is analyzed for training state, error histogram, fit, performance, and regression plots. Conclusively, the comprehensive analysis of the fluid dynamics, entropy generation, mass and heat transfer, and in the microchannel, coupled with the successful implementation of artificial neural network simulation, contributes to an improved understanding of the system’s behavior. Entropy generation was raised for enhanced Brownian motion number and reduced values of thermophoresis, activation energy, and endothermic–exothermic reaction parameters. This study’s results can be used to improve the efficiency and effectiveness of microfluidic devices used in fields as diverse as electrical cooling and medicine delivery. [ABSTRACT FROM AUTHOR]

Nanofluids have a wide range of applications in biological research. They are employed in targeted medication administration, hyperthermia (for cancer treatment) and differential diagnostics like magnetic resonance image (MRI). In light of these medical applications, the impact of an external magnetic field and an exponential heat source on the dynamics of Ti O 2 – H 2 O over a nonlinearly stretched surface has been investigated. A realistic modified Buongiorno model has been used which includes the effects of reaction rate, Biot number and activation energy. The boundary value problem governing the model is solved on MATLAB R2022a using the solver, BVP5C. Further, the consequences of different parameters on rate of heat transfer coefficient (Nusselt number), rate of mass transfer coefficient (Sherwood number), drag coefficient, velocity, temperature and volume fraction profile are observed graphically. It is noted that volume fraction and uniform heat source intensity have a positive effect on the Nusselt number and negative effect on Sherwood number. The effects of thermal radiation and magnetic field on volume fraction profile are, respectively, positive and negative. The current physics of flow across a vertical stretching surface is expected to serve as the foundation for various medical science, engineering and technology applications. [ABSTRACT FROM AUTHOR]

In the present paper, the effects of radiation, variable viscosity, and the inclination of the artery on copper nanofluid through composite stenosis with chemical reaction are discussed. The viscosity of blood is varied with temperature as represented in the Reynolds viscosity model. The coupled nonlinear equations of the nanofluid model are simplified by considering the mild stenosis case. The governing equations are solved numerically by applying the Finite Difference Method. The effects of the physical parameters on the velocity, temperature, and concentration along the radial axis have been studied and are physically interpreted for medical applications. The effect of shear stress along the increasing height of stenosis has been explained with the help of graphs. The proposed work will be beneficial to clinicians, hematologists, and biomedical engineers because they serve as useful approximations, which are capable of throwing some light toward the understanding of the genesis of pathological states, like arteriosclerosis as well as the mechanism of gaseous exchanges that take place within arteries and capillaries. [ABSTRACT FROM AUTHOR]

Efficient and highly functional three-dimensional systems that are ubiquitous in biology suggest that similar design architectures could be useful in electronic and optoelectronic technologies, extending their levels of functionality beyond those achievable with traditional, planar two-dimensional platforms. Complex three-dimensional structures inspired by origami, kirigami have promise as routes for two-dimensional to three-dimensional transformation, but current examples lack the necessary combination of functional materials, mechanics designs, system-level architectures, and integration capabilities for practical devices with unique operational features. Here, we show that two-dimensional semiconductor/semi-metal materials can play critical roles in this context, through demonstrations of complex, mechanically assembled three-dimensional systems for light-imaging capabilities that can encompass measurements of the direction, intensity and angular divergence properties of incident light. Specifically, the mechanics of graphene and MoS2, together with strategically configured supporting polymer films, can yield arrays of photodetectors in distinct, engineered three-dimensional geometries, including octagonal prisms, octagonal prismoids, and hemispherical domes. [ABSTRACT FROM AUTHOR]

Abstract: The transfer of synthesized large‐area 2D materials to arbitrary substrates is expected to be a vital step for the development of flexible device fabrication processes. The currently used hazardous acid‐based wet chemical etching process for transferring large‐area MoS2 films is deemed to be unsuitable because it significantly degrades the material and damages growth substrates. Surface energy‐assisted water‐based transfer processes do not require corrosive chemicals during the transfer process; however, the concept is not investigated at the wafer scale due to a lack of both optimization and in‐depth understanding. In this study, a wafer‐scale water‐assisted transfer process for metal–organic chemical vapor‐deposited MoS2 films based on the hydrofluoric acid treatment of a SiO2 surface before the growth is demonstrated. Such surface treatment enhances the strongly adhering silanol groups, which allows the direct transfer of large‐area, continuous, and defect‐free MoS2 films; it also facilitates the reuse of growth substrate. The developed transfer method allows direct fabrication of flexible devices without the need for a polymeric supporting layer. It is believed that the proposed method can be an alternative defect‐ and residue‐free transfer method for the development of MoS2‐based next‐generation flexible devices. [ABSTRACT FROM AUTHOR]

A long heated cylinder was placed near a cold wall under the incident of a Couette flow. The conventional fluid was chosen as water (H2O). The nanoparticle materials were selected as Al2O3 and CuO. The governing Navier-Stokes and energy equations were solved numerically through a finite volume method on a staggered grid system using QUICK scheme for convective terms and SIMPLE algorithm. The dependencies of hydrodynamic and heat transfer characteristics of the cylinder on non-dimensional parameters governing the nanofluids (Particle concentrations (φ), diameter (dnp), and particle materials) and the fluid flow (Peclet number Pe and gap height ratio L) were explored here. The shifting of the front stagnation point due to the addition of nanoparticles in the base fluid was investigated. A comparison between the heat transfer enhancement (NuM) of the cylinder and its drag coefficient's (CD) increment/reduction was made by presenting their ratio NuM/CD. The least square method was applied to the numerical results to propose NuM = NuM(Pe) and NuM = NuM(L). [ABSTRACT FROM AUTHOR]

Dumping of municipal solid waste into uncontrolled dumpsites is the most common method of waste disposal in most cities of India. These dumpsites are posing a serious challenge to environmental quality and sustainable development. Mumbai, which generates over 9000 t of municipal solid waste daily, also disposes of most of its waste in open dumps. It is important to analyse the impact of municipal solid waste disposal today and what would be the impact under integrated waste management schemes. In this study, life cycle assessment methodology was used to determine the impact of municipal solid waste management under different scenarios. Six different scenarios were developed as alternatives to the current practice of open dumping and partially bioreactor landfilling. The scenarios include landfill with biogas collection, incineration and different combinations of recycling, landfill, composting, anaerobic digestion and incineration. Global warming, acidification, eutrophication and human toxicity were assessed as environmental impact categories. The sensitivity analysis shows that if the recycling rate is increased from 10% to 90%, the environmental impacts as compared with present scenario would reduce from 998.43 kg CO2 eq t-1 of municipal solid waste, 0.124 kg SO2 eq t-1, 0.46 kg PO4-3 eq t-1, 0.44 kg 1,4-DB eq t-1 to 892.34 kg CO2 eq t-1, 0.121 kg SO2 eq t-1, 0.36 kg PO4-3 eq t-1, 0.40 kg 1,4-DB eq t-1, respectively. An integrated municipal solid waste management approach with a mix of recycling, composting, anaerobic digestion and landfill had the lowest overall environmental impact. The technologies, such as incineration, would reduce the global warming emission because of the highest avoided emissions, however, human toxicity would increase. [ABSTRACT FROM AUTHOR]

We demonstrate photo-patternable ion gel-gated graphene transistors and inverters on plastic substrates. The photo-patternable ion gel can be used as a negative photoresist for the patterning of underlying graphene as well as gate dielectrics. As a result, an extra graphene-patterning step is not required, which simplifies the device fabrication and avoids a side effect arising from the photoresist residue. The high capacitance of ion gel gate dielectrics yielded a low voltage operation (∼2 V) of the graphene transistor and inverter. The graphene transistors on plastic showed an on/off-current ratio of ∼11.5, along with hole and electron mobilities of 852 ± 124 and 452 ± 98 cm2 V−1 s−1, respectively. In addition, the flexible graphene inverter was successfully fabricated on plastic through the potential superposition effect from the drain bias. These devices show excellent mechanical flexibility and fatigue stability. [ABSTRACT FROM AUTHOR]

P-type polyaniline (PANI)/n-type ZnO based heterojunction is fabricated and the effect of continuous ultraviolet (UV) exposure on its current–voltage (I–V) characteristics is investigated. The I–V characteristics of PANI/ZnO showed diode-like behavior under dark condition and its ideality factor and barrier height were obtained as 1.54 and 1.35 eV, respectively. For immediate UV exposure the diode showed photo-characteristics, however, during continuous UV exposure diode characteristics started to change with exposure time. After sufficient exposure time characteristics became stable and the ideality factor and barrier height after UV exposure were obtained as 7.94 and 0.92 eV, respectively. It is proposed that the permanent physical changes in PANI film during UV exposure are responsible to change the rectifying behavior. It is found that after 10 min of continuous exposure the PANI film stabilizes and the PANI/ZnO junction shows stable characteristics. [ABSTRACT FROM AUTHOR]

A stretchable and transparent In-Ga-Zn-O (IGZO) thin film transistors with high electrical performance and scalability is demonstrated. A load-controlled roll transfer method is realized for fully automated and scalable transfer of the IGZO TFTs from a rigid substrate to a nonconventional elastomeric substrate. The IGZO TFTs exhibit high electrical performance under stretching and cyclic tests, demonstrating the potentiality of the load-controlled roll transfer in stretchable electronics. The mechanics of the load-controlled roll transfer is investigated and simulated, and it is shown that the strain level experienced by the active layers of the device can be controlled to well below their maximum fracture level during transfer. [ABSTRACT FROM AUTHOR]

The excellent impermeability of graphene was exploited to produce stable ohmic contact at the interface between Al metal and a semiconducting indium gallium zinc oxide (IGZO) layer after high-temperature annealing. Thin film transistors (TFTs) were fabricated with and without a graphene interlayer between the Al metal and the IGZO channel region. Metal contact at the interface prepared without a graphene interlayer showed serious instabilities in the IGZO TFT under thermal annealing; however, the insertion of a graphene interlayer between the IGZO channel and the Al metal offered good stability under repeated high-temperature annealing cycles and maintained ohmic contact. [ABSTRACT FROM AUTHOR]

Abstract: Films of polyaniline (PANI) and PANI–zinc oxide (ZnO) composites have been synthesized by solution cast and spin coating technique. The ZnO powder of particle size 100–200nm was synthesized by sol–gel technique and the polyaniline was synthesized by chemical oxidative polymerization of aniline. The composite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infra red (FTIR) and the results were compared with polyaniline films. Dielectric properties of PANI and PANI–ZnO composite films have been investigated between frequency ranges of 8.5 and 13.0GHz. The ‘a’ lattice parameter of ZnO was found to increase and the ‘c’ lattice parameter was found to decrease after ZnO–PANI composite formed. The characteristic FTIR peaks of PANI were found to shift to higher wave number in ZnO–PANI composite. These observed effects have been attributed to interaction of ZnO particles with PANI molecular chains. Dielectric constant of PANI–ZnO composite film was found to be smaller than the PANI film. The decrease of dielectric constant in PANI–ZnO films as compared to PANI was attributed to the interfaces formed between ZnO particles and PANI. [Copyright &y& Elsevier]

The article presents a study which investigates applicability of molybdenum disulfide in thin-film transistor and circuitry of organic light-emitting diode (OLED) display. it mentions that proposed architecture exhibits 28 times increase in mobility compared to a normal back-gated thin-film transistor, and its potential as a wearable display attached to a human wrist is demonstrated.

Development of energy harvesting system becomes one of the most important necessities of today. In this context, nanogenerators (NGs) have attracted considerable attentions in recent years due to their potential applications such as self-powered portable devices. This review article addresses the significant development of NGs systems based on semiconducting and insulating piezoelectric materials. Further, the need of mechanical flexibility and optical transparency on the demand of various electronic applications has been highlighted. In addition, we discussed some recent studies on graphene-based NGs which have been explored for stable performance of NGs. [ABSTRACT FROM AUTHOR]

A stretchable and transparent indium‐galliumzinc‐oxide (IGZO) thin‐film transistor (TFT) with high electrical performance and scalability is reported by Jae‐Hyun Kim, Jong‐Hyun Ahn, and co‐workers on page 2024. A load‐controlled roll transfer method is realized for fully automated and scalable transfer of the IGZO TFTs from a rigid substrate to an elastomeric substrate. The IGZO TFTs exhibit stable electrical performance without deformation or breakage when stretched and twisted, demonstrating the potentiality of the load‐controlled roll transfer in stretchable electronics. [ABSTRACT FROM AUTHOR]