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The absorption spectrum of 13 CH 4 is recorded in the center of the tetradecad near 1.73 μm (5695–5850 cm −1 ) at 296 K and 80 K by direct absorption spectroscopy (DAS). The achieved noise equivalent absorption of the spectra is α min  ≈ 5 × 10 −8  cm −1 leading to line intensity detectivity threshold on the order of 5 × 10 −26 and 5 × 10 −27  cm/molecule at 296 K and 80 K, respectively. As a result, two empirical line lists are constructed including about 3350 and 2070 lines at room temperature and liquid nitrogen temperature, respectively. For comparison, the HITRAN database provides in the region only the strongest 13 CH 4 lines (about 440 lines in total). From the intensity ratios of the lines measured at the two temperatures, 1529 empirical values of the lower state energy level ( E emp ) were derived. Their accuracy is reflected by the clear propensity of the corresponding empirical values of the lower state rotational quantum number, J emp , to be close to integer values. They provide accurate temperature dependence for 91% and 99% of the total 13 CH 4 absorption in the region at 296 K and 80 K, respectively. The comparison to the TheoReTS ab initio line list shows significant deviations for line positions. The obtained experimental data will be valuable to tune ab initio line positions to empirical values in future versions of the theoretical line lists. [ABSTRACT FROM AUTHOR]

This study uses time-diary data for dual-earner couples from Belgium, Denmark, Spain, and the United Kingdom to analyze educational inequalities in parental care time in different national contexts. For mothers, education is significantly associated with parenting involvement only in Spain and the United Kingdom. In Spain these differences are largely explained by inequalities in mothers' time and monetary resources, but not in the United Kingdom, where less-educated mothers disproportionally work in short part-time jobs. For fathers, education is associated with parenting time in Denmark, and particularly in Spain, while the wife's resources substantially drive these associations. On weekends, the educational gradient in parental care time applies only to Spain and the United Kingdom, two countries with particularly large inequalities in parents' opportunities to engage in parenting. The study shows country variations in educational inequalities in parenting, suggesting that socioeconomic resources, especially from mothers, shape important variations in parenting involvement. [ABSTRACT FROM AUTHOR]

The volume penalization (VP) or the Brinkman penalization (BP) method is a diffuse interface method for simulating multiphase fluid-structure interaction (FSI) problems in ocean engineering and/or phase change problems in thermal sciences and engineering. The method relies on a penalty factor (which is inversely related to body's permeability κ) that must be large to enforce rigid body velocity in the solid domain. When the penalty factor is large, the discrete system of equations becomes stiff and difficult to solve numerically. In this paper, we propose a projection method-based preconditioning strategy for solving volume penalized (VP) incompressible and low-Mach Navier-Stokes equations. The projection preconditioner enables the monolithic solution of the coupled velocity-pressure system in both single phase (uniform density and viscosity) and multiphase (variable density and viscosity) flow settings. In this approach, the penalty force is treated implicitly, which is allowed to take arbitrary large values without affecting the solver's convergence rate or causing numerical stiffness. It is made possible by including the penalty term in the pressure Poisson equation (PPE), which was not included in previous works that solved VP incompressible Navier-Stokes equations using the projection method. We show how and where the Brinkman penalty term enters the PPE by re-deriving the projection algorithm for the VP method. Solver scalability under grid refinement is demonstrated, i.e., convergence is achieved with the same number of iterations regardless of the problem size. A manufactured solution in a single phase setting is used to determine the spatial accuracy of the penalized solution. Various values of body's permeability κ are considered. Second-order pointwise accuracy is achieved for both velocity and pressure solutions for reasonably small values of κ. Error saturation occurs when κ is extremely small, but the convergence rate of the solver does not degrade. The solver converges faster as κ decreases, contrary to prior experience. Two multiphase fluid-structure interaction (FSI) problems from the ocean engineering literature are also simulated to evaluate the solver's robustness and performance (in terms of its number of iterations). The proposed solver also allows us to investigate the effect of κ on the motion of the contact line over the surface of the immersed body. It also allows us to investigate the dynamics of the free surface of a solidifying metal. • A projection preconditioner for volume penalized multiphase incompressible/low Mach Navier-Stokes equations is proposed. • The new projection method considers the Brinkman penalty term in both pressure Poisson and velocity update equations. • In contrast to prior experience, the solver convergence rate improves with decrease in body's permeability. • Second-order pointwise accuracy is achieved for both velocity and pressure solutions for reasonably small permeability values. • Challenging multiphase fluid-structure interaction and phase change problems are simulated using the proposed preconditioner. [ABSTRACT FROM AUTHOR]