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In this study, natural crystalline material collected from the head of the Pomadasys maculatus fishes are characterized for their potential applications in various fields including laser optics. Interestingly, the natural otolith crystals exhibit two-photon absorption-induced optical limiting characteristics under Nd:YAG laser excitation. The optical limiting threshold for otolith crystals was found to be $6.22\times 10^{12}$W/m². The presence of Calcium (Ca), Copper (Cu), Potassium (K), and Sodium (Na) is confirmed by ICP-OES analysis. The presence of Ca is primarily from the functional group of otolith that was found on the surface of otolith. From the GCMS analysis, 25 compounds were found in the methanol extract of otolith. The magnetic property of Pomadasys maculatus fish sample was analyzed by vibrating sample magnetometer (VSM). The decomposition/mass loss over a temperature was analyzed by thermogravimetric analysis (TGA) and also the endo and exothermic event temperatures and phase transitions were observed from Differential Thermal Analysis (DTA).

In this paper, a recent curved non-slip wall boundary treatment for isothermal Lattice Boltzmann equation (LBE) [Z. Guo, C. Zheng and B. Shi, Phys. Fluids14(6) (2002)] is extended to handle the thermal curved wall boundary for a double-population thermal lattice Boltzmann equation (TLBE). The unknown distribution population at a wall node which is necessary to fulfill streaming step is decomposed into its equilibrium and non-equilibrium parts. The equilibrium part is evaluated according to Dirichlet and Neumann boundary constraints, and the non-equilibrium part is obtained using a first-order extrapolation from fluid lattices. To validate the thermal boundary condition treatment, we carry out numerical simulations of Couette flow between two circular cylinders, the natural convection in a square cavity, and the natural convection in a concentric annulus between an outer square cylinder and an inner circular cylinder. The results agree very well with analytical solution or available data in the literature. Our numerical results also demonstrate that the TLBE together with the present boundary scheme is of second-order accuracy.

Standard results for the fluctuations of thermodynamic quantities are derived under the assumption of sampling identical systems that are in different, not fully equilibrated states. These results apply to fluctuations with time in a particular macroscopic body and can be traced to the fluctuations of thermal occupancy. When many identically prepared — but not identical — systems are studied, mesoscopic fluctuations due to variations from sample-to-sample contribute to the fluctuations of thermodynamic quantities. We study the combined effect of mesoscopic fluctuations and fluctuations of thermal occupancy. In particular, we evaluate the total particle number and specific heat fluctuations in a two-dimensional, noninteracting electron gas in classically integrable and chaotic circumstances.

This study describes the influence of thermal/plasma treatments on the structure and photocatalytic performance of the Au-doped TiO₂ catalyst. Au (gold) nanoparticles were attached on TiO₂ (Titania) nanoparticle surfaces by conventional deposition precipitation technique and the resulting catalysts were subsequently modified with thermal (at 450°C under vacuum) and plasma (at an ambient temperature under Argon atmosphere for 20 min) treatments. Structural characterization of the modified catalysts was performed by diverse analytical techniques and the photocatalytic activity was evaluated by assessing the degradation of the methylene blue (MB) in water under UV (ultra-violet) irradiations. Results showed that the thermal/plasma treatment significantly influenced the structural features of Au-doped TiO₂ catalyst by altering the morphology, increasing the Au nanoparticles population, improving the Au/TiO₂ catalytic activity, changing the textural properties and reducing the band gap energies thus tuned Au-doped TiO₂ catalyst to higher efficiency. Thermal/plasma treated Au-doped TiO₂ was found to exhibit higher photocatalytic activity than the as-synthesized (pristine sample). This improvement in photocatalytic activity might be due to the cathodic influence of gold in suppressing the electron–hole recombination during the reaction.

Leakage power is becoming a key design challenge in current and future CMOS designs. Due to technology scaling, the leakage power is rising so quickly that it largely elevates the die temperature. In this paper, we deeply investigate the impact of leakage power on thermal profile in both 2D and 3D floorplanning. Our results show that chip temperature can increase by about 11°C in 2D design and 68°C for 3D case with leakage power considered. Then we propose a thermal-driven floorplanning flow integrated with an iterative leakage-aware thermal analysis process to optimize chip temperature and save leakage power consumption. Experimental results show that for 2D design, the max chip temperature can be reduced by about 8°C and the proportion of leakage power to total power can be reduced from 19.17% to 11.12%. The corresponding results for 3D are 60°C temperature reduction and 16.3% less leakage power proportion.

The pyrolysis process of waste printed circuit board (WPCB) with high economic benefit has been a black box problem, limiting the upgrading of pyrolysis processes. The resourcefulness and hazardous nature of WPCB will make it necessary for it to be treated properly. Multiphysics model was built to simulate the whole processes of WPCB pyrolysis and contaminants’ release. The circuit board samples containing six components were selected for pyrolysis in a tube furnace at a rate of 10${}^{\circ }$C/min from room temperature to 600${}^{\circ }$C, and the residual rate of Br- was determined by the oxygen bomb method. The results showed that the difference in temperature distribution could be attributed to thermal conductivity and surface area. Heat distribution would be more even from the inner material in areas where holes existed. The assembly method would affect the stress distribution around the components. Thermal stress at the pins might cause the separation of components from the substrate. The concentration of brominated contaminants was influenced by the material and assembly method. The instantaneous concentration around the pin was 3–4 times compared to the bare substrate, which was beneficial for the release and control of brominated organics. This study provided the research method for the in-depth understanding of the pyrolysis process of complex materials; and provided a basis for the upgrading of related processes.

This work extends the seminal work of Gottfried on the two-body quantum physics of particles interacting through a delta-shell potential to many-body physics by studying a system of nonrelativistic particles when the thermal De-Broglie wavelength of a particle is larger than the range of the potential and the density is such that average distance between particles is larger than the above range. The ability of the delta-shell potential to reproduce some basic properties of the deuteron are examined. Relations for moments of bound-states are derived. The virial expansion is used to calculate the first quantum correction to the ideal gas pressure in the form of the second virial coefficient. Additionally, all thermodynamical functions are calculated up to the first-order quantum corrections. For small departures from equilibrium, the net flows of mass, energy and momentum, characterized by the coefficients of diffusion, thermal conductivity and shear viscosity, respectively, are calculated. Properties of the gas are examined for various values of physical parameters including the case of infinite scattering length when the unitary limit is achieved.

The thermal and mechanical properties of nasopharyngeal airway (NPA) samples are improved by irradiation using 4keV oxygen and nitrogen ion beams with different ion fluences varying from $25\times 10^{17}$ ions/cm² to $65\times 10^{17}$ ions/cm². The thermal stability of NPA medical device increases with increasing nitrogen and oxygen ion fluences. The tensile strength increased from 48MPa for unirradiated sample to 74MPa for samples irradiated with nitrogen and to 58MPa for samples irradiated with oxygen ion, while the elongation at break decreases for irradiated samples. Silver thin films are deposited on NPA medical device samples using 4keV argon ion beam. The XRD spectra demonstrated that silver nanoparticles are deposited on NPA medical device substrate. The effects of Ag thin film on gram-positive and gram-negative bacteria are studied.

Hybrid nanomaterials consisting of functionalized fullerene and gold nanoparticle (NP) have been synthesized. Fullerene was functionalized by citric acid and used as reducing and capping agent for preparation of gold NPs. Functionalization of fullerene by use of citric acid was performed by enzymatic and thermal approaches. The core-shell structures containing gold NPs as core and fullerene as shell (gold/fullerene) were prepared. It was found that method and density of functionalization of fullerene effect final structure and therefore their physicochemical property of hybrid nanomaterial dramatically. Ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), atomic force microscopy (AFM), transmission electron microscopy (TEM) were used to analyze the structure of the synthesized hybrid nanomaterial and also study their self-assembly and physicochemical properties. Effect of the size, structure and morphology (e.g., agglomeration) of the synthesized hybrid nanomaterial on their UV-Vis absorption behavior has been also verified by theoretical modeling.

In the present work, we study the static and dynamic behavior of a bi-layer cantilever micro-beam and its pull-in instability subjected to simultaneous effects of thermal moment, electrostatic force and mechanical shock. The nonlinear governing equation in the static case has been linearized using a Step-by-Step Linearization Method (SSLM) and the resulted linear equation has been solved using a Finite Difference Method (FDM). The obtained results for some cases have been compared to the existing results and good agreement achieved. The dynamic response of the system owing to application of a mechanical shock and a step DC voltage for thermally actuated micro-beam have been accomplished by a partial differential equation. A Reduced-Order Model (ROM) has been used to simulate the dynamic behavior of the micro-beam. The effects of temperature changes and mechanical shock on the pull-in behavior have been studied and obtained results show an earlier pull-in phenomenon experience when these effects are considered.

Since its first demonstration of an acoustic metamaterial in the early 21st century, it is widely used for sound wave manipulation purposes in many applications such as aerospace, automotive, defense, marine, etc. However, the traditional acoustic metamaterials display acoustic characteristics for restricted use because of their fixed structures. For real-world applications, the active sound wave manipulation is desirable. In recent years, active acoustic metamaterials (AAMs) have garnered attention owing to their unique design and material characteristics, which result in various dynamic responses against the incoming sound wave. This paper aims to provide an overview of the fundamental concept of active metamaterials, describing the multiple tuning mechanisms and design strategies, and highlighting their potential applications. The current fabrication challenges and future outlook in this promising field are also discussed.

Ag/Co nanoparticles (NPs) were prepared by a two-step method. First, Ag NPs were synthesized by "Controlled Current Coulometry" (CCC) electrochemical method using a Pt rotating electrode. Then, Ag/Co core-shell NPs were prepared through the reduction method using Ag NPs as a core. Both steps were accomplished at room temperature. Techniques such as patterned X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed for the characterization of Ag/Co NPs. Optical properties of synthesized NPs were also investigated by UV-Vis spectroscopy. The absorption peak of Ag NPs was observed at ~400 nm wavelength and the peaks that were detected at 425 nm and 415 nm wavelengths reveal the formation of Ag/Co NPs. The core-shell structure of Ag/Co NPs was confirmed by thermal and electrochemical techniques. We also applied "Mie" theory to calculate the absorption cross-section band of synthesized Ag/Co NPs. Comparison between the results of optical properties and also those obtained from "Mie" theory showed good agreements.

The molar entropy (ΔS) and molar enthalpy (ΔH) for the denaturation event that triggers cutaneous erythema was determined to be ΔS = 190 J/(mole K) and ΔH = 146.9 × 10³ J/mole. The experiment involved placing heated water against the skin of the forearm, for a range of temperatures and exposure times. Exposing the skin to 45°C for 22 s was at the threshold for producing erythema, which was similar to the threshold for a slight degree of pain.

Pyroelectric composites of triglycine sulfate (TGS)-polyvinylidene difluoride (PVDF) doped with graphene are studied. It is found that the graphene can effectively improve the polling efficiency and thermal property of the composites so that the infrared detective performance can be significantly improved. For example, by adding about 0.83 wt.% of graphene, the infrared detective property can be improved by more than 30%. It is also found that the size of the graphene plays a critical role on the property improvement. For example, the small-sized graphene prepared by ultrasonic exfoliation (UE) method is more effective than the big-sized graphene prepared by electrochemical exfoliation (EE) method.

Thermal management in the looming world of electronic packaging system is the most prior and conspicuous issue as far as the working efficiency of the system is concerned. The cooling in such systems can be achieved by impinging air jet over the heat sink as jet impingement cooling is one of the cooling technologies which are widely studied now. Here the modulation in impinging and geometric parameters results in the establishment of the characteristic cooling rate over the target surface. The characteristic cooling curve actually resembles non-uniformity in cooling rate. This non-uniformity favors the area average heat dissipation rate. In order to study the non-uniformity in cooling characteristic, the present study takes an initiative in plotting the local Nusselt number magnitude against the non-dimensional radial distance of the different thickness of target surfaces. For this, the steady temperature distribution over the target surface under the impingement of air jet is being determined numerically. The work is completely inclined towards the determination of critical value of geometric thickness below which the non-uniformity in the Nusselt profile starts. This is done by numerically examining different target surfaces under constant Reynolds number and nozzle-target spacing. The occurrences of non-uniformity in Nusselt profile contributes to over a 42% enhancement in area average Nusselt magnitude. The critical value of characteristic thickness (t/d) reported in the present investigation approximate to 0.05. Below this value, the impingement of air jet generates a discrete pressure zones over the target surface in the form of pressure spots. As a result of this, the air flowing in contact with the target surface experiences a damping potential, in due of which it gets more time and contact with the surface to dissipate heat.

This study aims to explore the buckling behavior of rectangular plate with angle-ply overlay under thermal and mechanical loadings using meshless method. The governing differential equations (GDEs) of the plate are based on a new higher-order shear deformation theory (HSDT) and are discretized using polynomial radial basis function (RBF) to cast a set of equations simultaneously. A code is developed for the solution in MATLAB (2019). Uniform temperature differences and mechanical loads are the cause of in-plane loads. Convergence study has been conducted to check the current formulation’s soundness. The accuracy of the contemporary theory and formulation is validated with the published results. A parametric investigation is conducted for buckling behavior under the span-to-thickness ratio, lamination scheme, effect of the number of layers and effect of length-to-width ratio.

Pretreatment equipment for food waste preparation is described at a laboratory and industrial scale. Small-scale methods include sonication, ultrasound, and microwave. The majority of industrial-scale installations rely on mechanical particle size reduction and heat treatment. Pretreatment equipment may be used not only to prepare food waste for anaerobic digestion (AD) but also to remove contaminants harmful to the AD process, enhance AD process performance, and achieve regulatory compliance: particularly in achieving product and process hygiene standards. The need for whole-life assessment of pretreatment technology is discussed, particularly in terms of energy consumption and environmental risks associated with the dispersal of plastic residues and microplastics.

We examine recent prescriptions for estimating the thermal Casimir force between two metallic plates from the point of view of their consistency with the Bohr-van Leeuwen theorem of classical statistical physics. We find that prescriptions including the effect of ohmic dissipation satisfy the theorem, while prescriptions that neglect ohmic dissipation do not.