The adsorption behavior of toxic gas molecules (NO, CO, NO 2 , and NH 3 ) on graphene-like BC 3 are investigated using first-principle density functional theory (DFT). The most stable adsorption configurations, adsorption energies, binding distances, charge transfers, electronic band structures, and the conductance modulations are calculated to deeply understand the impacts of the molecules above on the electronic and transport properties of the BC 3 monolayer. The graphene-like BC 3 monolayer is a semiconductor with a band gap of 0.733 eV. The semi-metal graphene has a low sensitivity to the abovementioned molecules. However, it is discovered that all the above gas molecules are chemically adsorbed on the BC 3 sheet with the adsorption energies less than −1 eV. The NO 2 gas molecule is totally dissociated into NO and O species through the adsorption process, while the other gas molecules retain their molecular forms. The amounts of charge transfer upon adsorption of CO and NH 3 gas molecules on BC 3 are found to be small. Hence, the band gap changes in BC 3 as a result of interactions with CO and NH 3 are only 4.63% and 16.7%, indicating that the BC 3 -based sensor has a low and moderate sensitivity to CO and NH 3 , respectively. Contrariwise, upon adsorption of NO or NO 2 on BC 3 , a significant charge is transferred from the molecules to the BC 3 sheet, causing a semiconductor-metal transition. It is found that the BC 3 -based sensor has high potential for NO detection due to the significant conductance changes, moderate adsorption energy, and short recovery time. More excitingly, the BC 3 is a likely catalyst for dissociation of the NO 2 gas molecule. Our findings divulge promising potential of the graphene-like BC 3 as a highly sensitive molecular sensor for NO and NH 3 detection and a catalyst for NO 2 dissociation.

An Eulerian/Lagrangian approach is used to calculate the physical forces acting on a spherical bubble. Reynolds average Navier-Stokes (RANS) equations for the Eulerian approach are solved with a finite volume scheme. The SIMPLE algorithm is utilized for pressure and velocity linkage. To model convective fluxes, an upwind scheme is used. The Reynolds stress transport model (RSTM) is used to calculate the turbulent parameters. In the Lagrangian approach, a modified form of the Reyleigh-Plesset (RP) and Maxey equations are solved with MATLAB programming software for evaluation of bubble motion and bubble dynamics. The carrying fluid in this study is diesel fuel. Continuous filter white noise (CFWN) is solved parallel to the Maxey and RP equations to calculate fluctuating terms of velocity in x and y directions. Six forces exerted on the bubble during its motion are investigated inside the cavitating flow regime. The cavitating regime can be extremely effective on bubble force and increase bubble forces up to several thousand times. Added mass force in the y direction has the highest value among all forces exerted on the bubble during its motion inside the nozzle.

A methodology for non-destructive simultaneous estimation of spatially varying thermal conductivity and heat capacity in 2D solid objects was developed that requires only boundary measurements of temperatures. The spatial distributions were determined by minimizing the normalized sum of the least-squares differences between measured and calculated values of the boundary temperatures. Computing time was significantly reduced for the entire inverse parameter identification process by utilizing a metamodel created by an analytical response surface supported by an affordable number of numerical solutions of the temperature fields obtained by the high fidelity finite element analyses. The minimization was performed using a combination of particle swarm optimization and the BFGS algorithm. The methodology has shown to accurately predict linear and nonlinear spatial distributions of thermal conductivity and heat capacity in arbitrarily shaped multiply-connected 2D objects even in situations with noisy measurement data thus proving that it is robust and accurate. The current drawback of this method is that it requires an a priori knowledge of the general spatial analytic variation of the physical properties. This can be remedied by representing such variations using products of infinite series such as Fourier or Chebyshev and determining correct values of their coefficients.

A B S T R A C TA fully 3D conjugate numerical analysis was performed to reveal the effects of air, R134a refrigerant and water on electromagnetic fields of electronic cooling designs made of arrays of micro pin-fins with integrated Through-Silicon-Vias (TSVs). The integrated TSV cooling configuration included 8 cylindrical TSVs with 150 µm diameter each and 200 µm height. The external dimensions of the silicon substrate were 900×700×280 µm. Each TSV encapsulated four equally spaced copper vias each having a diameter of 40 µm. The impacts of the presence of the stationary cooling fluids without heat transfer on TSVs electric and magnetic fields were examined for five different frequencies; 100 MHz, 500 MHz, 1 GHz, 5 GHz and 10 GHz. Then, separately, the effects of moving cooling water with temperature-dependent physical properties were studied while exposing the cooled micro pin-fin array to a uniform heat flux of 500 W cm −2 . For the case of stagnant and moving cooling fluids it was found that water influences the electric field twice as much as either R134a or air and that this influence decreases only negligibly with the increase in frequency of the electric current passing through the TSVs. The influence of the presence of the stagnant and moving cooling fluids on the magnetic field is orders of magnitude smaller and reduces rapidly with the increased frequency.