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Abstract Additive manufacturing of thermoplastic elastomeric material (TPE) using direct ink writing (DIW) based printing technique opens new horizons for various applications. However, the most crucial process in DIW 3D printing is the optimization of printing parameters to obtain high-quality products both in terms of aesthetics and strength. In this work, statistical models were developed considering layer height, print speed, and, ink concentration to obtain the optimized print quality product from the blend of thermoplastic polyurethane (TPU)/ epichlorohydrin − ethylene oxide − allyl glycidyl ether elastomer (GECO) based TPE materials. Experiments were designed according to the central composite design (CCD) scheme and the influence of input printing parameters on shrinkage and tensile strength was analyzed. The significance of each parameter was systematically studied using the response surface method. For both responses, shrinkage, and tensile strength, printing speed was found to be the most significant parameter. Ink concentration significantly affected tensile strength with a contribution of ∼ 34%. On the other hand, the layer height, with a contribution of ∼ 22% significantly affected the shrinkage behaviour of the 3D printed sample. Finally, multi-objective optimization was performed using a genetic algorithm to identify the optimal 3D printing parameters of the developed TPE materials.

Abstract Multifunctional flexible conductive materials have generated significant interest in developing future portable electronic systems, including wearable electronics, implantable devices, and many more. Producing wearable electronics materials that are dependable in all-weather situations and provide high-performance electromagnetic interference (EMI) shielding remains challenging. "electromagnetic textile materials" refers to these wearable EMI shielding garments. One key material that can address the EMI problem facing systems such as wearable/flexible circuit working environments and human health is conductive polymeric nonwoven (NW) textile materials. In this review, our focus is primarily limited to the polymeric NW textile and their composites family as effective EMI shielding materials. The study provides the fundamentals of NW-based EMI shielding mechanisms, mechanisms to mitigate EM reflection, and fabrication techniques of EMI shielding NW materials. Also, the standard for future researchers to select the ideal material combination for effectively mitigating EMI waves as shields/filters is presented. Review articles exist on EMI shielding textiles in general, but no single article is dedicated to NW textile-based EMI shields. Again, no review article exists presenting the approaches employed towards mitigating EM wave reflection in NW -based EMI shield design and fabrication. In addition, the challenges encountered with the fabrication and/or application of NW-based EMI shielding materials are presented in this paper. The question of why NW selection is the primary structure for EMI shield fabrication is presented herewith for the first time in this article.

Abstract The selective distribution of filler within polymer blends presents a compelling advantage, notably manifesting as a reduced percolation threshold when compared to an individual polymer matrix with a random filler dispersion. In this context, a thermoplastic elastomeric (TPE) blend comprising ethylene propylene diene rubber (EPDM) and linear low-density polyethylene (LLDPE), denoted as EL, has been meticulously formulated. The incorporation of varying amounts of conductive carbon black (Vulcan XC 72; VCB) into this TPE matrix has been achieved through conventional melt blending, yielding a composite material with exceptional electromagnetic interference (EMI) shielding effectiveness of -27.80 dB at 50 phr (parts per hundred rubber). This success is credited to the creation of a linked structure resulting from a dual-step percolation process. The selective distribution of carbon black (CB) throughout the TPE mixture results in a decreased critical concentration for connectivity and enhanced electromagnetic interference (EMI) shielding performance. This advancement underscores the potential of EPDM-LLDPE-VCB (ELV) composites to safeguard against electromagnetic radiation. It paves the way for their utilization in various techno-commercial applications, where a balance of mechanical strength, thermal stability, and flexibility is crucial. Graphical Abstract

Abstract The deformation behavior of Ti-6Al-4V titanium alloy is significantly influenced by slip localized within crystallographic slip bands. Experimental observations reveal that intense slip bands in Ti-6Al-4V form at strains well below the macroscopic yield strain and may serially propagate across grain boundaries, resulting in long-range localization that percolates through the microstructure. These connected, localized slip bands serve as potential sites for crack initiation. Although slip localization in Ti-6Al-4V is known to be influenced by various factors, an investigation of optimal microstructures that limit localization remains lacking. In this work, we develop a novel strategy that integrates an explicit slip band crystal plasticity technique, graph networks, and neural network models to identify Ti-6Al-4V microstructures that reduce the propensity for strain localization. Simulations are conducted on a dataset of 3D polycrystals, each represented as a graph to account for grain neighborhood and connectivity. The results are then used to train neural network surrogate models that accurately predict localization-based properties of a polycrystal, given its microstructure. These properties include the ratio of slip accumulated in the band to that in the matrix, fraction of total applied strain accommodated by slip bands, and spatial connectivity of slip bands throughout the microstructure. The initial dataset is enriched by synthetic data generated by the surrogate models, and a grid search optimization is subsequently performed to find optimal microstructures. Describing a 3D polycrystal with only a few features and a combination of graph and neural network models offer robustness compared to the alternative approaches without compromising accuracy. We show that while each material property is optimized through a unique microstructure solution, elongated grain shape emerges as a recurring feature among all optimal microstructures. This finding suggests that designing microstructures with elongated grains could potentially mitigate strain localization without compromising strength.

Abstract Unraveling the effects of continuous dislocation interactions with interfaces, particularly at the nanometer length scales, is key to a broader understanding of plasticity, to material design and to material certification. To this end, this work proposes a novel discrete dislocation dynamics-based model for dislocation interface interactions tracking the fate of residual dislocation on interfaces. This new approach is used to predict the impact of dislocation/interface reactions on the overall mechanical behavior of accumulative roll bonded nanometallic laminates. The framework considers the dynamic evolution of the interface concurrent with a large network of dislocations, thus, accounting for the local short and long range effects of the dislocations under the external boundary conditions. Specifically, this study focuses on two-phase Fe/Cu nanometallic laminates, and investigates the role of the underlying elastic and plastic contrast of the Fe and the Cu layers on the composite response of the material. Moreover, the role of initial microstructures, resulting from processing is also investigated. Subsequently, the model is used to examine the effect of layer thickness and interface orientation relationship on the residual stresses of the relaxed microstructure. The associated mechanical response of these laminates are compared when loaded under normal direction compression, as well as shear compression. Finally, this work predicts a dominant effect of the layer thickness, as compared to the interface orientation relationship, on the macroscopic response and on the residual stresses of these nanolaminates, while the local dislocation transmission propensity through the interface is significantly influenced by the corresponding orientation relationship.

Abstract Modeling dislocations is an inherently multiscale problem as one needs to simultaneously describe the high stress fields near the dislocation cores, which depend on atomistic length scales, and a surface boundary value problem which depends on boundary conditions on the sample scale. We present a novel approach which is based on a peridynamic dislocation model to deal with the surface boundary value problem. In this model, the singularity of the stress field at the dislocation core is regularized owing to the non-local nature of peridynamics. The effective core radius is defined by the peridynamic horizon which, for reasons of computational cost, must be chosen much larger than the lattice constant. This implies that dislocation stresses in the near-core region are seriously underestimated. By exploiting relationships between peridynamics and Mindlin-type gradient elasticity, we then show that gradient elasticity can be used to construct short-range corrections to the peridynamic stress field that yield a correct description of dislocation stresses from the atomic to the sample scale.

Abstract This article comprehensively discusses the mechanical and tribological properties of epoxy matrix composites filled with 100μm graphite particulates, at loadings ranging from 0 to 1wt%. The investigation also focuses on the effects of the graphite filler on the wear surface of the specimens, utilizing an optical microscope for analysis. The results revealed a significant decrease in the tensile strength of the composite, with a reduction of more than 50% observed at 1wt% graphite loading. However, the flexural strength exhibited an initial sharp increase at 0.1wt% graphite loading, followed by a decline at higher graphite contents. Moreover, both impact and hardness values demonstrated improvement as the graphite content increased. The addition of graphite particles led to a reduction in the friction coefficient, attributed to the solid lubrication capabilities of graphite. Furthermore, the wear rate exhibited a sharp decrease with an increase in graphite content due to the formation of a lubrication layer at the contact surface, effectively reducing the break-off of the specimen.

Abstract Heat-based local ablation techniques are effective treatments for specific oligometastatic and localized cancers and are being studied for their potential to induce immunogenic cell death and augment systemic immune responses to immunotherapies. The diverse technologies associated with thermal therapy have an unmet need for method development to enable device-specific experimentation, optimization, calibration and refinement of the parameter space to optimize therapeutic intent while minimizing side effects or risk to the patient. Quality assurance, training, or comparing thermal dose among different modalities or techniques using animal models is time and resource intensive. Therefore, the application and use of tissue mimicking thermosensitive, thermochromic liquid crystal and thermochromic paint phantom models may reduce costs and hurdles associated with animal use. Further, their homogenous composition may enable more precise assessment of ablative techniques. This review utilized SciFinder, Web of Science, PubMed and EMBASE to systematically evaluate the literature describing the background and applications of thermochromic liquid crystal, thermochromic paint and tissue-mimicking thermochromic phantoms used to characterize the thermal effects of ablation devices with a focus on facilitating their use across the medical device development life cycle. Graphical Abstract

Abstract Sheet Moulding Compound (SMC) based composites have a large potential in industrial contexts due to the possibility of achieving comparatively short manufacturing times. It is however necessary to be able to numerically predict both mechanical properties as well as manufacturability of parts. In this paper a fully 3D, semi-empirical model based on fluid mechanics for the compression moulding of SMC is described and discussed, in which the fibres and the resin are modelled as a single, inseparable fluid with a viscosity that depends on volume fraction of fibres, shear strain rate and temperature. This model is applied to an advanced carbon-fibre SMC with a high fibre volume fraction (35%). Simulations are run on a model of a squeeze test rig, allowing comparison to experimental results from such a rig. The flow data generated by this model is then used as input for an Advani-Tucker type of model for the evolution of the fibre orientation during the pressing process. Numerical results are also obtained from the software 3DTimon. The resulting fibre orientation distributions are then compared to experimental results that are obtained from microscopy. The experimental measurement of the orientation tensors is performed using the Method of Ellipses. A new, automated, accurate and fast method for the ellipse fitting is developed using machine learning. For the studied case, comparison between the experimental results and numerical methods indicate that 3D Timon better captures the random orientation at the outer edges of the circular disc, while 3D CFD show larger agreement in terms of the out-of-plane component. One of the advantages of the new image technique is that less work is required to obtain microscope images with a quality good enough for the analysis.

Abstract Given the greater global awareness of environmental impacts of plastics and the need to develop alternative materials from renewable natural resources, there has been an increasing drive over recent years to develop biobased and biodegradable composites, especially those produced from agro-industrial waste and byproducts. This perspective provides a brief introduction to the field as well as discussing some of the critical aspects to be considered as we accelerate the development of these novel alternative materials for a range of applications.

Abstract Incorporating inorganic nanomaterials into a polymer matrix is one of the most effective ways to create thermoelectric performance for applications where physical flexibility is essential. In this study, flexible thermoelectric nanocomposite films were synthesized by incorporating inorganic copper iodide (CuI) nanosheets as the filler into poly (3,4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT: PSS). The process involved the preparation of bulk CuI from precursors and, subsequently, the nanosheet synthesis by dissolving the bulk CuI in dimethyl sulfoxide (DMSO). The morphology of the nanosheets and the nanocomposite films was thoroughly examined, and the film’s thermoelectric performance was evaluated using a standard thermoelectric measurement system, ZEM-3. The morphological observation revealed a triangular nanosheet geometry for CuI, with an average lateral dimension of ~33 nm. The PEDOT/CuI nanocomposite films were prepared by mixing CuI nanosheets with PEDOT: PSS through ultrasonication and filtration on a PVDF membrane. The film with 6.9 vol% of CuI nanosheets exhibited an electrical conductivity and Seebeck coefficient of 852.07 S·cm-1 and 14.95 µV·K-1, respectively. This resulted in an enhanced power factor of 19.04 µW·m-1·K-2, much higher than the individual composite components. It demonstrated a trend of increasing power factor with the nanosheets up to 6.9 vol% due to improved electrical conductivity. The increase in electrical conductivity can be attributed to the screening effect induced by DMSO, which leads to a conformational change in the PEDOT chains. Furthermore, an optimal fraction of CuI nanosheets also contributes to this conformational change, further enhancing the electrical conductivity. Graphical Abstract

Abstract Graphene enhanced thermoplastic composites offer the possibility of conductive aerospace structures suitable for applications from electrostatic dissipation, to lightning strike protection and heat dissipation. Spray deposition of liquid phase exfoliated (LPE) aqueous graphene suspensions are highly scalable rapid manufacturing methods suitable to automated manufacturing processes. The effects of residual surfactant and water from LPE on thin films for interlaminar prepreg composite enhancement remain unknown. This work investigates the effect of heat treatment on graphene thin films spray deposited onto carbon fibre/polyether ether ketone (CF/PEEK) composites for reduced void content. Graphene thin films deposited onto CF/PEEK prepreg tapes had an RMS roughness of 1.99 μm and an average contact angle of 11°. After heat treatment the roughness increased to 2.52 μm with an average contact angle of 82°. The SEM images, contact angle, and surface roughness measurements correlated suggesting successful removal of excess surfactant and moisture with heat treatment. Raman spectroscopy was used to characterise the chemical quality of the consolidated graphene interlayer. Spectral data concluded the graphene was 3–4 layered with predominantly edge defects suggesting high quality graphene suitable for electrical enhancement. Conductive-AFM measurements observed an increase in conductive network density in the interlaminar region after the removal of surfactant from the thin film. Heat treatment of the Control sample successfully reduced void content from 4.2 vol% to 0.4 vol%, resulting in a 149% increase in compressive shear strength. Comparatively, heat treatment of graphene enhanced samples (~ 1 wt%) reduced void content from 5.1 vol% to 2.8 vol%. Although a 25% reduction in shear strength was measured, the improved electrical conductivity of the interlaminar region extends the potential applications of fibre reinforced thermoplastic composites. The heat treatment process proves effective in reducing surfactant and thus void content while improving electrical conductivity of the interlayer in a scalable manner. Further investigations into graphene loading effects on conductive enhancement, and void formation is needed.

Abstract Aluminium matrix composites (AMC) do combine a high lightweight potential with a wide range of specific mechanical or thermal properties, depending on their material composition or the content of reinforcement particles, respectively. Currently, the three main production technologies for manufacturing such AMC are powder metallurgy, semi-solid processes and casting. Here, the AMC´s reinforcement proportion that can be processed depends on the chosen manufacturing strategy and is therefore often limited to a maximum value of 30 vol. %, due to agglomeration and porosity problems. In this context, the main objective is to understand the fundamental mixing behaviour of powder mixtures for AMC green body production having reinforcement contents of up to 50 vol.% SiCp. For this purpose, powder mixtures of monomodal AlSi7Mg0.6 and different SiCp fractions were prepared with different mixing times and speeds to investigate the influence of these mixing parameters on the homogeneity of the particle distribution. Afterwards, the influence of powder size on the mixing process was investigated. The results showed that a slower mixing speed resulted in faster homogenisation as well as a larger particle size can be faster mixed. Furthermore, a regression model was developed using mixing time, speed and particle loading, to determine sufficient mixing parameters.

Abstract Epoxy is widely used material, but epoxy has limitations in terms of brittleness in failure, and thus researchers explore toughening and strengthening options such as adding a second phase or using electromagnetic fields to tailor toughness and strength, on demand and nearly instantaneously. Such approach falls into the category of active toughening but has not been extensively investigated. In this research, Si-BaTiO3 nanoparticles were used to modify the electro-mechanical properties of a high-performance aerospace-grade epoxy so as to study its response to electric fields, specifically low field strengths. To promote uniform dispersion and distribution, the Si-BaTiO3 nanoparticles were functionalised with silane coupling agents and mixed in the epoxy Araldite LY1564 at different content loads (1, 5, 10 wt%), which was then associated with its curing agent Aradur 3487. Real-time measurements were conducted using Raman spectroscopy while applying electric fields to the nanocomposite specimens. The Raman data showed a consistent trend of increasing intensity and peak broadening under the increasing electric field strength and Si-BaTiO3 contents. This was attributed to the BaTiO3 particles’ dipolar displacement in the high-content nanocomposites (i.e., 5 wt% and 10 wt%). The study offers valuable insights on how electric field stimulation can actively enhance the mechanical properties in epoxy composites, specifically in relatively low fields and thin, high-aspect-ratio composite layers which would require in-situ mechanical testing equipped with electric field application, an ongoing investigation of the current research.

Abstract This review highlights the advantages of incorporating hexagonal Boron Nitride (BN) into the current membrane-based architectures for water remediation over other well-explored 2D nanomaterials such as graphene, graphene oxide, molybdenum sulphide, MXenes. BN has an interlayer spacing of 3.3A0 which is similar to that of graphene, but smaller than that of the other 2D nanomaterials. BN is bioinert, and stable under harsh chemical and thermal conditions. When combined with thin film composite and mixed matrix membrane architectures, BN can help achieve high permeance, dye rejection, and desalination. Laminar membranes assembled by BN nanosheets do not swell uncontrollably in aqueous environments unlike graphene oxide. BN nanomaterials have a large specific surface area which implies more adsorption sites, and are inherently hydrophobic in nature, which means the adsorbent in its powder form can be easily separated from contaminated water. BN adsorbents can be regenerated by treating with chemicals or heating to high temperatures to remove the adsorbate, without damaging the BN, due to its thermal and chemical inertness. BN nanomaterials have the potential to circumvent the current shortcomings of membranes and adsorbents, while greatly enhancing the performance of membranes and adsorbents for water remediation. Graphical Abstract

Abstract Drone technology is widely available and is rapidly becoming a crucial instrument in the functions of businesses and government agencies worldwide. The demand for delivery services is accelerating particularly since the Covid-19 pandemic. Both companies and customers want these services to be efficient, timely, safe, and sustainable, but these are major challenges. Last-mile delivery by lightweight short-range drones has the potential to address these challenges. However, there is a lack of consistency and transparency in assessing and reporting the sustainability of last-mile delivery services and drones. This paper critically reviews published papers on Life Cycle Assessments of drones to date. The study reveals a lack of comprehensive studies, and a need to examine composite and battery manufacturing developments and provides key considerations for future study development. Graphical Abstract

Abstract A study on electrical conduction of carbon/epoxy laminates has so far been conducted in an ad hoc nature without a standardised method, involving many extrinsic factors. How these factors affect electrical conduction of carbon/epoxy laminates has not been well established. The objectives of this work are to ascertain the effects of electrical currents, temperatures, and clamping torques on the anisotropic electrical conduction of carbon/epoxy laminates. Two-probe method with solid electrodes was developed with machined carbon/epoxy laminate specimens of various dimensions. The contributions of elevated temperatures and clamping pressures to electrical conduction were investigated. Various contact conditions with or without conductive paint were examined. The relationship of electrical resistance correlating with temperature and clamping pressure was developed to aid an analysis of data trends. From the average test results of 18 groups, aided with qualitative predictions, the milliampere-to-ampere increases of current led to significant reductions in electrical conductivities in both in-plane and through-the-thickness directions. The rises of temperatures resulted in the similar reductions in electrical conductivity due to the increased resistance. The increase in clamping torque increased the electrical conductivity values in both directions. Applying conductive paint to the contact faces did not appear to affect the contact resistance. Thus, the enhanced values of electrical conductivity from the painted specimens were attributed to their lower body temperatures, as the conductive paint at the contact faces soaked up the substantial amount of the electrical energies.

Abstract The presented work collects results from the evaluation of electrical response to mechanical deformation and formation of defects presented by different polymeric based composite materials with potential for applications in Structural Health Monitoring and Strain Detection. With the aim of showing the variety of key materials in sectors like civil aviation, wind energy, automotive or railway that present this ability, specimens of very different nature have been analyzed: a) thermoplastic commercial 3D printing filaments loaded with carbonic fillers; b) epoxy resin loaded with Carbon Nanotubes and c) long carbon fiber reinforced resin composite. Measurements of electrical properties of these materials were taken to evaluate their capability to detect the presence of structural defects of different sizes as well as its spatial location. On the other hand, simultaneous measurements of electrical resistivity and mechanical strain during tensile tests were performed to analyze the potential of materials as strain detectors. All composites studied have shown a positive response (modification of electrical performance) to external mechanical stimulus: induced damage and deformations. Graphical Abstract

Abstract The modern-day computing technologies are continuously undergoing a rapid changing landscape; thus, the demands of new memory types are growing that will be fast, energy efficient and durable. The limited scaling capabilities of the conventional memory technologies are pushing the limits of data-intense applications beyond the scope of silicon-based complementary metal oxide semiconductors (CMOS). Resistive random access memory (RRAM) is one of the most suitable emerging memory technologies candidates that have demonstrated potential to replace state-of-the-art integrated electronic devices for advanced computing and digital and analog circuit applications including neuromorphic networks. RRAM has grown in prominence in the recent years due to its simple structure, long retention, high operating speed, ultra-low-power operation capabilities, ability to scale to lower dimensions without affecting the device performance and the possibility of three-dimensional integration for high-density applications. Over the past few years, research has shown RRAM as one of the most suitable candidates for designing efficient, intelligent and secure computing system in the post-CMOS era. In this manuscript, the journey and the device engineering of RRAM with a special focus on the resistive switching mechanism are detailed. This review also focuses on the RRAM based on two-dimensional (2D) materials, as 2D materials offer unique electrical, chemical, mechanical and physical properties owing to their ultrathin, flexible and multilayer structure. Finally, the applications of RRAM in the field of neuromorphic computing are presented.

Abstract Piezoelectric microelectromechanical system (piezo-MEMS)-based mass sensors including the piezoelectric microcantilevers, surface acoustic waves (SAW), quartz crystal microbalance (QCM), piezoelectric micromachined ultrasonic transducer (PMUT), and film bulk acoustic wave resonators (FBAR) are highlighted as suitable candidates for highly sensitive gas detection application. This paper presents the piezo-MEMS gas sensors’ characteristics such as their miniaturized structure, the capability of integration with readout circuit, and fabrication feasibility using multiuser technologies. The development of the piezoelectric MEMS gas sensors is investigated for the application of low-level concentration gas molecules detection. In this work, the various types of gas sensors based on piezoelectricity are investigated extensively including their operating principle, besides their material parameters as well as the critical design parameters, the device structures, and their sensing materials including the polymers, carbon, metal–organic framework, and graphene.

Abstract We report the chemical synthesis of poly(aniline-co-aniline-2,5-disulfonic acid)) and its composite containing L-hexuronic acid and metallic Ag/SiO2 nanoparticles as a new thermally stable anionic polyelectrolyte for removing safranin dye. The composite was characterized by IR, UV, cyclic voltammetry, SEM, TEM, TGA, DSC, EDXS and elemental analyses. Microscopic images exhibited intensified spherical particles dispersed over almost the entire surface. The XRD exhibited peaks of the partially crystalline material at many 2θ values, and their interatomic spacing and sizes were calculated. The cyclic voltammograms exhibited characteristic redox peaks relative to the quinoid ring transition states. The uptake rates up to 82.5% adsorption were completed within 75 min and the equilibrium time was 45 min. The isotherm of dye adsorption interprets the interaction with the adsorbent and explain the relationship between the dye removal capacity and the initial dye concentration. In the current, the Langmuir isotherm model was the optimum to interpret both the dye/copolymer and the dye/composite interactions. The uptake of safranin by copolymer/SiO2@Ag nanocomposite was well defined by pseudo second order model with rate constant K2 = 0.03 g− 1 mg− 1 min− 1 for 19 mg safranin. A comparison of safranin adsorption efficiency of the synthesized material with other reported material in the same domain suggested that the present composite has a higher adsorption rate and capacity. The ongoing research is devoted to improving the removal percentage of the dye by using 1,3,5-triazine based sulfonated polyaniline/Ag@ SiO2 nanocomposite.

Abstract Large-area, continuous monolayer WS2 exhibits great potential for future micro-nanodevice applications due to its special electrical properties and mechanical flexibility. In this work, the front opening quartz boat is used to increase the amount of sulfur (S) vapor under the sapphire substrate, which is critical for achieving large-area films during the chemical vapor deposition processes. COMSOL simulations reveal that the front opening quartz boat will significantly introduce gas distribute under the sapphire substrate. Moreover, the gas velocity and height of substrate away from the tube bottom will also affect the substrate temperature. By carefully optimizing the gas velocity, temperature, and height of substrate away from the tube bottom, a large-scale continues monolayered WS2 film was achieved. Field-effect transistor based on the as-grown monolayer WS2 showed a mobility of 3.76 cm2V−1 s−1 and ON/OFF ratio of 106. In addition, a flexible WS2/PEN strain sensor with a gauge factor of 306 was fabricated, showing great potential for applications in wearable biosensors, health monitoring, and human–computer interaction.

Abstract Perovskites are the key enabler materials for the solar cell applications in the achievement of high performance and low production costs. In this article, the structural, mechanical, electronic, and optical properties of rubidium-based cubic nature perovskite LiHfO3 and LiZnO3 are investigated. These properties are investigated using density-functional theory with the aid of CASTEP software by introducing ultrasoft pseudo-potential plane-wave (USPPPW) and GG-approximation-PB-Ernzerhof exchange–correlation functionals. It is investigated that the proposed compounds exhibit stable cubic phase and meet the criteria of mechanical stability by the estimated elastic properties. Also, according to Pugh's criterion, it is noted that LiHfO3 is ductile and LiZnO3 is brittle. Furthermore, the electronic band structure investigation of LiHfO3 and LiZnO3 shows that they have indirect bandgap (BG). Moreover, the BG analysis of the proposed materials shows that these are easily accessible. Also, the results for partial density of states (DOS) and total DOS confirm the degree of a localized electron in the distinct band. In addition, the optical transitions in the compounds are examined by fitting the damping ratio for the notional dielectric functions scaling to the appropriate peaks. At absolute zero temperature, the materials are observed as semiconductors. Therefore, it is evident from the analysis that the proposed compounds are excellent candidates for solar cells and protective rays applications.

Article highlights In this review article we have covered the state-of-the-art microfluidic methodologies for the synthesis of a broad range of nanoparticle (NPs) for potential applications in the fields of biomedicine and drug delivery. Apart from the experimental methodologies, this review also details the most common multiscale simulation methods used to unravel the critical mechanisms involved in nanoparticle synthesis and their interactions with other entities. A comprehensive summary of the microfluidic techniques, divided into passive and active micro-mixing methods, have been provided, while highlighting advantages and disadvantages of individual methods. We have discussed challenges related to NPs synthesis, their application in new fields, and future perspectives.

Abstract Urine test paper is a standard, noninvasive detection method for direct bilirubin, but this method can only achieve qualitative analysis and cannot achieve quantitative analysis. This study used Mini-LEDs as the light source, and direct bilirubin was oxidized to biliverdin by an enzymatic method with ferric chloride (FeCl3) for labeling. Images were captured with a smartphone and evaluated for red (R), green (G), and blue (B) colors to analyze the linear relationship between the spectral change of the test paper image and the direct bilirubin concentration. This method achieved noninvasive detection of bilirubin. The experimental results demonstrated that Mini-LEDs can be used as the light source to analyze the grayscale value of the image RGB. For the direct bilirubin concentration range of 0.1–2 mg/dL, the green channel had the highest coefficient of determination coefficient (R 2) of 0.9313 and a limit of detection of 0.56 mg/dL. With this method, direct bilirubin concentrations higher than 1.86 mg/dL can be quantitatively analyzed with the advantage of rapid and noninvasive detection.

Abstract An ultra-small mid-infrared plasmonic nanowire laser based on n-doped GaN metallic material is proposed and studied by the finite-difference time-domain method. In comparison with the noble metals, nGaN is found to possess superior permittivity characteristics in the mid-infrared range, beneficial for generating low-loss surface plasmon polaritons and achieving strong subwavelength optical confinement. The results show that at a wavelength of 4.2 µm, the penetration depth into the dielectric is substantially decreased from 1384 to 163 nm by replacing Au with nGaN, and the cutoff diameter of nGaN-based laser is as small as 265 nm, only 65% that of the Au-based one. To suppress the relatively large propagation loss induced by nGaN, an nGaN/Au-based laser structure is designed, whose threshold gain has been reduced by nearly half. This work may pave the way for the development of miniaturized low-consumption mid-infrared lasers.

Abstract Recently, flexible sensors with high sensitivity have been applied in wearable sports sensing field. Here, we reported a flexible and sensitive capacitive pressure sensor based on nylon textile and polyvinylidene fluoride (PVDF) dielectric film. From the experimental results, the sensor has an extremely high sensitivity of 33.5 kPa−1, a low detection limit of 0.84 Pa, a quick response time of 27 ms. Moreover, the pressure sensor shows excellent reliability under over 100,000 working cycles. With their superior overall performance, capacitive sensors have effectively proved their enormous potential for basketball motion monitoring. This research will promote the development of wearable sports sensors.

Abstract In this review, the radiolytic and physical methods that can be used for the functionalization of carbon nanotubes (CNTs) and their applications as a support for fuel cell electrodes are described. Alloy nanoparticles have also been examined. For example, Pt–Ru nanoparticles were deposited onto a functionalized multiwalled carbon nanotube (MWNT) composite by reducing metal ions (e.g., Pt4+ and Ru3+) here using γ-irradiation and, hence, creating Pt–Ru/MWNT catalysts. The morphology, size, and composition of these Pt–Ru/MWNT catalysts were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and elemental analysis, respectively. The efficiency of the Pt–Ru/MWNT catalyst was examined for use in the oxidation of carbon monoxide (CO) and methanol. The results of stripping voltammetry for the adsorbed CO on the Pt–Ru/MWNT catalyst electrodes indicated that CO oxidation was energetically favorable at these electrodes. Thus, Pt–Ru/MWNT catalysts were found to be suitable for electrode assembly in direct methanol fuel cells.

Abstract Photodetectors (PDs) suffer from dark current due to defects in the perovskite photosensitive layer. Contact between the photosensitive layer and carbon electrodes could result in recombination of carriers at the interface. In this work, CsPbI3 quantum dots (QDs) were added between the photosensitive layer and the carbon electrode as the interfacial layer to passivate the surface defects of perovskite layer and improve the energy level matching at the interface. The effect of QDs concentrations on the passivation of the perovskite layer was investigated. It was found that the photoluminescence intensity of perovskite films was the strongest and the decay lifetime was the longest when the QDs concentration was 3 mg/mL. Owing to QDs passivation, the dark current of perovskite PD decreased by 94% from $$2.04\; \times \;10^{ - 9}$$ 2.04 × 10 - 9 to $$1.17\; \times \;10^{ - 10}$$ 1.17 × 10 - 10 A. The responsivity (R) at 605 nm improved by 27% from 0.29 to 0.37 A/W at 0 V bias voltage. The specific detectivity (D*) increased by 420% from $$8.9\; \times \;10^{11}$$ 8.9 × 10 11 to $$4.7\; \times \;10^{12}$$ 4.7 × 10 12 Jones.

Abstract Due to the widespread applications of metal nanoparticles (NPs), green synthesis strategies have recently advanced, e.g., methods that utilize extracts made from different plant wastes. A particularly innovative approach to reducing large amounts of available household/agricultural green wastes is their application in nanoparticle generation. Regarding this, the aim of our work was to examine the possibility of upgrading green nanoparticle syntheses from an innovative economic and environmental point of view, namely by investigating the multiple recyclabilities of green tea (GT), coffee arabica (CA), and Virginia creeper (Parthenocissus quinquefolia) (VC) waste residues for iron nanoparticle (FeNPs) synthesis. The plant extracts obtained by each extraction round were analyzed individually to determine the amount of main components anticipated to be involved in NPs synthesis. The synthesized FeNPs were characterized by X-ray powder diffraction and transmission electron microscopy. The activity of the generated FeNPs in degrading chlorinated volatile organic compounds (VOC) and thus their future applicability for remediation purposes were also assessed. We have found that VC and especially GT residues could be reutilized in multiple extraction rounds; however, only the first extract of CA was suitable for FeNPs’ generation. All of the obtained FeNPs could degrade VOC with efficiencies GT1-Fe 91.0%, GT2-Fe 83.2%, GT3-Fe 68.5%; CA1-Fe 76.2%; VC1-Fe 88.2%, VC2-Fe 79.7%, respectively, where the number (as in GT3) marked the extraction round. These results indicate that the adequately selected green waste material can be reutilized in multiple rounds for nanoparticle synthesis, thus offering a clean, sustainable, straightforward alternative to chemical methods. Graphical abstract

Abstract We study the electrical and morphological properties of random arrays of Ge nanowires (NW) deposited on sapphire substrates. NW-based devices were fabricated with the aim of developing chemiresistive-type sensors for the detection of explosive vapours. We present the results obtained on pristine and annealed NWs and, focusing on the different phenomenology observed, we discuss the critical role played by NW–NW junctions on the electrical conduction and sensing performances. A mechanism is proposed to explain the high efficiency of the annealed arrays of NWs in detecting 2,4,6 trinitrotoluene vapours. This study shows the promising potential of Ge NW-based sensors in the field of civil security.

Abstract The idea of benefitting from the properties of III-V semiconductors and silicon on the same substrate has been occupying the minds of scientists for several years. Although the principle of III-V integration on a silicon-based platform is simple, it is often challenging to perform due to demanding requirements for sample preparation rising from a mismatch in physical properties between those semiconductor groups (e.g. different lattice constants and thermal expansion coefficients), high cost of device-grade materials formation and their post-processing. In this paper, we demonstrate the deposition of group-III metal and III-V semiconductors in microfabricated template structures on silicon as a strategy for heterogeneous device integration on Si. The metal (indium) is selectively electrodeposited in a 2-electrode galvanostatic configuration with the working electrode (WE) located in each template, resulting in well-defined In structures of high purity. The semiconductors InAs and InSb are obtained by vapour phase diffusion of the corresponding group-V element (As, Sb) into the liquified In confined in the template. We discuss in detail the morphological and structural characterization of the synthesized In, InAs and InSb crystals as well as chemical analysis through scanning electron microscopy (SEM), scanning transmission electron microscopy (TEM/STEM), and energy-dispersive X-ray spectroscopy (EDX). The proposed integration path combines the advantage of the mature top-down lithography technology to define device geometries and employs economic electrodeposition (ED) and vapour phase processes to directly integrate difficult-to-process materials on a silicon platform. Graphical abstract

Abstract Fabrication of high-quality semiconductor thin films has long been a subject of keen interest in the photocatalytic field. Here, we report a facile, solution-based anodic plating and calcination for large-scale synthesis of BiVO4 thin films on indium tin oxide coated glass for use as photoanodes in solar water splitting. Using Na2SO3 as a sacrificial reagent, continuous solar H2 production with 94% Faradaic efficiency was obtained over 6 h of photoelectrochemical water splitting.

Abstract We focus on a novel concept of photosynthetic soft membranes, possibly able to allow the conversion of solar energy and carbon dioxide (CO $$_2$$ 2 ) into green fuels. The considered membranes rely on self-assembled functional molecules in the form of soap films. We elaborate a multi-scale and multi-physics model to describe the relevant phenomena, investigating the expected performance of a single soft photosynthetic membrane. First, we present a macroscale continuum model, which accounts for the transport of gaseous and ionic species within the soap film, the chemical equilibria and the two involved photocatalytic half reactions of the CO $$_2$$ 2 reduction and water oxidation at the two gas–surfactant–water interfaces of the soap film. Second, we introduce a mesoscale discrete Monte Carlo model, to deepen the investigation of the structure of the functional monolayers. Finally, the morphological information obtained at the mesoscale is integrated into the continuum model in a multi-scale framework. The developed tools are then used to perform sensitivity studies in a wide range of possible experimental conditions, to provide scenarios on fuel production by such a novel approach.

Abstract Raman spectroscopy can quickly achieve non-destructive, qualitative and quantitative detection, and analysis the molecular structure of substances. Herein, a facile and low-cost method for preparation of highly sensitivity SERS substrates was implemented through the displacement reaction of copper foam immersed in AgNO3 ethanol solution. Due to the 3D structure of copper film and homogenous displacement, the Ag–Cu substrate showed high performance SERS enhancement (1.25 × 107), and the lowest detection concentration for R6G reached 10–10 Mol/L. For glucose detection, mixed decanethiol (DT)/mercaptohexanol (MH) interlayer was used to enable glucose attach to the substrate surface, and the limit of detection reached to 1 uM/L. SERS substrate makes the Ag–Cu SERS substrate promising for biological applications.

Abstract Element doping is an important method for improving the performance levels of photoelectrochemical (PEC) cells. Nevertheless, to date, the PEC conversion efficiency and photocurrent characteristics of the available photoanodes remain very low. In this study, cobalt (Co) was selectively doped into the bottom and/or top layers of double-layered α-Fe2O3 nanorod arrays grown on conductive transparent substrates (F:SnO2, FTO) via a two-step hydrothermal method; this process was performed to enhance the charge transfer ability and thus significantly improve the PEC performance. The light response capabilities of all α-Fe2O3 films were evaluated by an electrochemical workstation under dark or visible light irradiation conditions. The sample of Co doped in the bottom layer exhibited a high photoelectrochemical performance, achieving a current density of 1.37 mA/cm2 at + 1.0 V versus saturated calomel electrode (SCE); additionally, the sample exhibited a photoelectric synergistic ability to reduce Cr(VI) in an aqueous solution, with 84.85% reduction in 180 min. Under the influence of the electric field inside the double-layer electrode, the photoexcited electrons and holes are transferred to the surfaces of the FTO substrate and the photoanode, increasing the current density and enhancing Cr(VI) reduction. The results of this study offer an alternative approach for designing novel photoanodes with improved PEC performance levels by engineering the electron density distribution and band structure for efficient carrier separation; the results may provide new solutions in heavy metal reduction and contaminant degradation projects.

Abstract The biological methods are considered as environmental-eco-friendly methods for the silver nanocomposites mediation and are widely used in this context. However, the biological methods go along with the relevant limitations, for instance simultaneous synthesis of silver chlorides (AgNCl) type during the AgNPs mediation process. Therefore, the present research is coming to summarize several aspects in this context. Firstly, to present the possible promotion of the sustainable development using bioactive source (e.g. milk) as a source of two different available and new lactobacillus strains (Lactobacillus curvatus and Lactobacillus fermentum). Secondly, to show the ability of the respective isolates to be involved in mediation of various biosilver nanocomposites ((Bio)NCs) synthesis. Moreover, at this stage, for the first time, two (Bio)NCs mediation methods, called “direct method” and “modified method”, have been developed, thus three types (AgNPs, AgNCl and AgNP@AgNCl) of nanocomposites mediated by two different Lactobacillus isolates take place. The interdisciplinary approach included using several spectroscopic, microscopic, spectrometric and thermogravimetric methods demonstrated that all six synthesized nanoparticles (three AgNPs, AgNCl and AgNP@AgNCl types from each source) consist of complex structure including both metallic silver core as well as organic surface deposits. The spectrometric technique allowed to identification of the organics branching surface, naturally secreted by the used Lactobacillus isolates during the inoculation step, suggesting the presence of amino-acids sequences which are direct connected with the reduction of silver ion to metal silver, and subsequently with the formation of coated (Bio)NCs and nucleation process. Moreover, based on the obtained results, the mediation mechanism of each (Bio)NCs has been proposed, suggesting that the formation of AgNPs, AgNCl and AgNP@AgNCl types occurs in different manners with faster synthesis firstly of AgNCl, then of the AgNPs type. No differences between the (Bio)NCs synthesized by two different Lactobacillus isolates have been noticed indicating no discrepancies between metabolites secreted by the respective sources. Graphical abstract

Abstract A new, sizable family of 2D transition metal carbonitrides, carbides, and nitrides known as MXenes has attracted a lot of attention in recent years. This is because MXenes exhibit a variety of intriguing physical, chemical, mechanical, and electrochemical characteristics that are closely linked to the wide variety of their surface terminations and elemental compositions. Particularly, MXenes are readily converted into composites with materials including oxides, polymers, and CNTs, which makes it possible to modify their characteristics for a variety of uses. MXenes and MXene-based composites have demonstrated tremendous promise in environmental applications due to their excellent reducibility, conductivity, and biocompatibility, in addition to their well-known rise to prominence as electrode materials in the energy storage sector. The remarkable characteristics of 2D MXene, including high conductivity, high specific surface area, and enhanced hydrophilicity, account for the increasing prominence of its use in storage devices. In this review, we highlight the most recent developments in the use of MXenes and MXene-based composites for electrochemical energy storage while summarizing their synthesis and characteristics. Key attention is paid to applications in supercapacitors, batteries, and their flexible components. Future research challenges and perspectives are also described.

Abstract We propose and demonstrate a novel range of models to accurately determine the optical properties of nitrogen-free carbon quantum dots (CQDs) with ordered graphene layered structures. We confirm the results of our models against the full range of experimental results for CQDs available from an extensive review of the literature. The models can be equally applied to CQDs with varied sizes and with different oxygen contents in the basal planes of the constituent graphenic sheets. We demonstrate that the experimentally observed blue fluorescent emission of nitrogen-free CQDs can be associated with either small oxidised areas on the periphery of the graphenic sheets, or with sub-nanometre non-functionalised islands of sp 2 -hybridised carbon with high symmetry confined in the centres of oxidised graphene sheets. Larger and/or less symmetric non-functionalised regions in the centre of functionalised graphene sheet are found to be sources of green and even red fluorescent emission from nitrogen-free CQDs. We also demonstrate an approach to simplify the modelling of the discussed sp 2 -islands by substitution with equivalent strained polycyclic aromatic hydrocarbons. Additionally, we show that the bandgaps (and photoluminescence) of CQDs are not dependent on either out-of-plane corrugation of the graphene sheet or the spacing between sp 2 -islands. Advantageously, our proposed models show that there is no need to involve light-emitting polycyclic aromatic molecules (nanographenes) with arbitrary structures grafted to the particle periphery to explain the plethora of optical phenomena observed for CQDs across the full range of experimental works.

Abstract Plasticity modelling has long relied on phenomenological models based on ad-hoc assumption of constitutive relations, which are then fitted to limited data. Other work is based on the consideration of physical mechanisms which seek to establish a physical foundation of the observed plastic deformation behavior through identification of isolated defect processes (’mechanisms’) which are observed either experimentally or in simulations and then serve to formulate so-called physically based models. Neither of these approaches is adequate to capture the complexity of plastic deformation which belongs into the realm of emergent collective phenomena, and to understand the complex interplay of multiple deformation pathways which is at the core of modern high performance structural materials. Data based approaches offer alternative pathways towards plasticity modelling whose strengths and limitations we explore here for a simple example, namely the interplay between rate and dislocation density dependent strengthening mechanisms in fcc metals.

Abstract A procedure for defining virtual spaces, and the periodic one-electron and two-electron integrals, for plane-wave second quantized Hamiltonians has been developed, and it was validated using full configuration interaction (FCI) calculations, as well as executions of variational quantum eigensolver (VQE) circuits on Quantinuum’s ion trap quantum computers accessed through Microsoft’s Azure Quantum service. This work is an extension to periodic systems of a new class of algorithms in which the virtual spaces were generated by optimizing orbitals from small pairwise CI Hamiltonians, which we term as correlation optimized virtual orbitals with the abbreviation COVOs. In this extension, the integration of the first Brillouin zone is automatically incorporated into the two-electron integrals. With these procedures, we have been able to derive virtual spaces, containing only a few orbitals, that were able to capture a significant amount of correlation. The focus in this manuscript is on comparing the simulations of small molecules calculated with plane-wave basis sets with large periodic unit cells at the $$\Gamma$$ Γ -point, including images, to results for plane-wave basis sets with aperiodic unit cells. The results for this approach were promising, as we were able to obtain good agreement between periodic and aperiodic results for an LiH molecule. Calculations performed on the Quantinuum H1-1 quantum computer produced surprisingly good energies, in which the error mitigation played a small role in the quantum hardware calculations and the (noisy) quantum simulator results. Using a modest number of circuit runs (500 shots), we reproduced the FCI values for the 1 COVO Hamiltonian with an error of 11 milliHartree, which is expected to improve with a larger number of circuit runs.

Abstract Self-healing materials can increase the lifetime of products and improve their sustainability. However, the detection of damage in an early stage is essential to avoid damage progression and ensure a successful self-healing process. In this study, self-healing sensor composite strips were developed with the embedding of a thermoplastic styrene-based co-polymer (TPS) sensor in a self-healing matrix. Piezoresistive TPS sensor fibers composites (SFCs) and 3D printed sensor element composites (SECs) were fabricated and embedded in a self-healing matrix by lamination process to detect damage. In both cases, the value of the initial resistance was used to detect the presence of damage and monitor the efficiency of healing. A higher elongation at fracture could be achieved with the extruded sensor fibers. However, for the composite strips the SECs could achieve a higher elongation at fracture. Mechano-electrical analysis revealed that the strips maintained a monotonic, reproducible response after the healing of the matrix. The SFCs had significantly lower drift of the sensor signal during cyclic mechanical analysis. Nevertheless, on a tendon-based soft robotic actuator, the SECs obtained a drift below 1%. This was explained by the lower deformation (e.g.) strain in comparison to the tensile test experiments.

Abstract Particulate matter (PM) in the environment can adversely affect the health of living things. However, high removal efficiency and low-pressure loss are crucial design challenges for any air filtration system. To circumvent the challenge, here, we demonstrate a novel triboelectric (TE) air filtration system that is based on a rotation-type triboelectric nanogenerator (TENG) and a filter comprising two sets of plates: primary and secondary, that are placed in the airflow channel. When the TENG charges the two plate sets with opposite charges, the flowing air particles are charged at the primary plates and are collected, due to an electric field, at the secondary plates. The TE filter has demonstrated a PM2.5 removal efficiency of ~ 99.97% for the fine dust particles, and it remains stable even after several washing cycles. The pressure loss is almost two orders less than the high-efficiency particulate air filter. Since the airflow itself can drive the TENG, the TE filter can potentially be integrated with any air conditioning system for fine dust filtration in offices, automobiles, etc.

Abstract GaAs-on-Si templates with two different dislocation filter layers (DFLs) were grown at 550 °C low-temperature (LT)-DFL and 660 °C high-temperature (HT)-DFL using metal organic vapor-phase epitaxy and the effects of the growth temperature were studied. The threading dislocation density (TDD) values of LT-DFL and HT-DFL were 5.2 × 107 cm−2 and 1.5 × 107 cm−2, respectively. The 1.5 × 107 cm−2 of TDD in HT-DFL is reduced by almost one order compared to the 1.2 × 108 cm−2 of that in the control sample without DFLs. The annihilation process was mainly observed in the HT-DFL by a transmission electron microscope, resulting in a lower TDD. The 500-nm-thick GaAs bulk layer and InAs QDs were regrown on GaAs-on-Si templates and the optical properties were also evaluated by photoluminescence (PL). The highest PL peak intensity of the HT-DFL indicates that less non-radiative recombination in both the GaAs bulk and QDs occurred due to the reduced TDD. The GaAs p–i–n diodes were also fabricated to analyze the bulk leakage (J B) and the surface leakage current. The J B of HT-DFL shows the lowest value of 3.625 × 10–7 A/cm−2 at applied bias voltage of 1 V, which is 20 times lower than the J B of the control sample without DFLs. This supports that the high-temperature growth of DFL can make a good performance GaAs device on Si.

Abstract Carbon-based nanomaterials are promising for a wide range of biomedical applications, i.e. drug delivery, therapy, and imaging including photoacoustic tomography, where they can serve as contrast agents, biocompatibility and biodistribution of which should be assessed before clinical setting. In this paper, localization of carbon flurooxide nanoparticles, carbon nanodots from β-alanine, carbon nanodots from urea and citric acid and glucose-ethylenediamine nanoparticles (NPs) in organs of Wistar rats were studied by photoacoustic measurements after 24 h of their intravenous injection. 16 ns light pulse from a Q-switched Nd:YAG laser with 1064 nm wavelength was used as an excitation source. The laser-induced photoacoustic signals were recorded with a ring piezoelectric detector. Light absorption by carbon NPs resulted in noticeable enhancement of the photoacoustic amplitude in the tissues where the NPs were accumulated. The NPs were preferably accumulated in liver, kidneys and spleen, and to a lesser extent in heart and gastrocnemius muscles. Together with remarkable fluorescent properties of the studied carbon nanomaterials, their photoacoustic responses allow their application for bi-modal fluorescence-photoacoustic bio-imaging.

Abstract Radiotherapy is an important modality for the treatment of cancer, e.g., X-ray, Cs-137 γ-ray (peak energy: 662 keV). An important therapy pathway of radiation is to generate the double strand breaks of DNA to prohibit the proliferation of cancer cells. In addition, the excessive amount of reactive oxygen species (ROS) is induced to damage the organelles, which can cause cellular apoptosis or necrosis. Gold nanoparticles (GNPs) have been proven potential as a radiosensitizer due to the high biocompatibility, the low cytotoxicity and the high-Z property (Z = 79) of gold. The latter property may allow GNPs to induce more secondary electrons for generating ROS in cells as irradiated by high-energy photons. In this paper, the radiobiological effects on A431 cells with uptake of 55-nm GNPs were studied to investigate the GNPs-enhanced production of ROS on these cells as irradiated by Cs-137 γ-ray. The fluorescence-labeling image of laser scanning confocal microscopy (LSCM) shows the excessive expression of ROS in these GNPs-uptake cells after irradiation. And then, the follow-up disruption of cytoskeletons and dysfunction of mitochondria caused by the induced ROS are observed. From the curves of cell survival fraction versus the radiation dose, the radiosensitization enhancement factor of GNPs is 1.29 at a survival fraction of 30%. This demonstrates that the tumoricidal efficacy of Cs-137 radiation can be significantly raised by GNPs. Because of facilitating the production of excessive ROS to damage tumor cells, GNPs are proven to be a prospective radiosensitizer for radiotherapy, particularly for the treatment of certain radioresistant tumor cells. Through this pathway, the tumoricidal efficacy of radiotherapy can be raised.

Abstract In this work, extremely thin silicon-on-insulator field effective transistors (ETSOI FETs) are fabricated with an ultra-thin 3 nm ferroelectric (FE) hafnium zirconium oxides (Hf0.5Zr0.5O2) layer. Furthermore, the subthreshold characteristics of the devices with double gate modulation are investigated extensively. Contributing to the advantages of the back-gate voltage coupling effects, the minimum subthreshold swing (SS) value of a 40 nm ETSOI device could be adjusted from the initial 80.8–50 mV/dec, which shows ultra-steep SS characteristics. To illustrate this electrical character, a simple analytical model based on the transient Miller model is demonstrated. This work shows the feasibility of FE ETSOI FET for ultra-low-power applications with dynamic threshold adjustment.

Abstract In this study, for the first time, the effects of temperature and nanopowder volume fraction (NPSVF) on the viscosity and the rheological behavior of SAE50–SnO2–CeO2 hybrid nanofluid have been studied experimentally. Nanofluids in NPSVFs of 0.25% to 1.5% have been made by a two-step method. Experiments have been performed at temperatures of 25 to 67 °C and shear rates (SRs) of 1333 to 2932.6 s−1. The results revealed that for base fluid and nanofluid, shear stress increases with increasing SR and decreasing temperature. By increasing the temperature to about 42 °C at a NPSVF of 1.5%, about 89.36% reduction in viscosity is observed. The viscosity increases with increasing NPSVF about 37.18% at 25 °C. In all states, a non-Newtonian pseudo-plastic behavior has been observed for the base fluid and nanofluid. The highest relative viscosity occurs for NPSVF = 1.5%, temperature = 25 °C and SR = 2932.6 s−1, which increases the viscosity by 37.18% compared to the base fluid. The sensitivity analysis indicated that the highest sensitivity is related to temperature and the lowest sensitivity is related to SR. Response surface method, curve fitting method, adaptive neuro-fuzzy inference system and Gaussian process regression (GPR) have been used to predict the dynamic viscosity. Based on the results, all four models can predict the dynamic viscosity. However, the GPR model has better performance than the other models.

Abstract GaSb-based single-transverse-mode narrow ridge waveguide (RW) lasers with high power and simultaneous good beam quality have broad application prospects in the mid-infrared wavelength region. Yet its design and formation have not been investigated systematically, while the beam characteristics that affect their suitability for specific applications remain rarely analyzed and optimized. The present work addresses these issues by theoretically establishing a waveguide parameter domain that generalizes the overall possible combinations of ridge widths and etch depths that support single-transverse-mode operation for GaSb-based RW lasers. These results are applied to develop two distinct and representative waveguide designs derived from two proposed major optimization routes of model gain expansion and index-guiding enhancement. The designs were evaluated experimentally based on prototype 1-mm cavity-length RW lasers in the 1950 nm wavelength range, which were fabricated with waveguides having perpendicular ridge and smooth side-walls realized through optimized dry etching conditions. The model gain expanded RW laser design with a relatively shallow-etched (i.e., 1.55 $$\upmu$$ μ m) and wide ridge (i.e., 7 $$\upmu$$ μ m) yielded the highest single-transverse-mode power to date of 258 mW with a narrow lateral divergence angle of 11.1 $$^\circ$$ ∘ full width at half maximum at 800 mA under room-temperature continuous-wave operation, which offers promising prospects in pumping and coupling applications. Meanwhile, the index-guiding enhanced RW laser design with a relatively deeply etched (i.e., 2.05 $$\upmu$$ μ m) and narrow ridge (i.e., 4 $$\upmu$$ μ m) provided a highly stable and nearly astigmatism-free fundamental mode emission with an excellent beam quality of M $$^2$$ 2 factor around 1.5 over the entire operating current range, which is preferable for seeding external cavity applications and complex optical systems.