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The article focuses on advancing sustainable synthesis through electrochemical carbonyl hydrogenation on M–N–C catalysts. Specific catalysts exhibit oxyphilicity or carbophilicity, selectively converting aldehydes to hydrocarbons or acetaldehyde/acetone to ethanol/2-propanol. The study highlights mechanistic insights and the potential for sustainable electrocatalytic valorization of biomass-derived compounds in green chemistry.

This chapter discusses the current state of research of artificial atoms (superatoms) (quasiatomic nanoheterostructures) and more complex nanostructures based on themsynthetic molecules, proposed a new model of an artificial atom, satisfactorily explaining its electronic properties, as well as the prospects for the development of the new scientific field. [ABSTRACT FROM AUTHOR]

A new implementation of the Continuous Surface Stress (CSS) method into a quad/octree grid structure is presented, which realizes effective adaptive mesh refinement (AMR) for computation of interfacial flows with significant topology changes. The momentum conservation property of the CSS method is exactly retained. The extension of the CSS method to the AMR framework and a designed phase-based refinement criterion are described in detail. The new implementation works on 2D/3D and on axis-symmetric grids. The proposed method is shown to be accurate in the computation of the Laplace pressure. The spurious velocity is evaluated based on the benchmark cases of static droplet and translating droplet. The test case of multiple droplets colliding onto a liquid film illustrates the functionality and efficiency of the method in dealing with complex interfacial flows. Thanks to the high resolution realized by AMR, it is shown in computation of the process of binary droplet collisions that the method is capable of capturing finest interfacial structures subjected to complex topology changes. • Momentum conservation property of the CSS method exactly retained. • Computation of multiple droplets impact onto a liquid film by a single work station. • Finest interfacial structures captured within collision complex. [ABSTRACT FROM AUTHOR]

We present an efficient method for generating maximum entanglement in one-dimensional atomic lattices. The proposed method relies on adiabatic rapid transfer into two Rydberg states with strongly asymmetric interactions. The method is suitable for Rydberg S states in the absence of applied electrostatic fields. We show numerical simulations of entanglement generation in rubidium atoms using calculated van der Waals potentials under realistic experimental conditions. We study the effect of the chosen Rydberg states on the final entanglement. [ABSTRACT FROM AUTHOR]

The dynamic multipole polarizabilities and thus the second-order van der Waals coefficients C2K of all orders are known exactly for the interaction between two classical spherical conducting shells, each of uniform electron density ρ with outer radius R and thickness t. The result is C2K = -ck(t / R)√4π ρ[(2R)2]k. The ck approach a limiting constant value, so the infinite series for the van der Waals interaction at separation d, -C6/d6 - C8/d8 - …, can be summed analytically, diverging only for d ≤ 2R. This divergence can be removed without changing the asymptotic series. Real quasispherical objects like nanoclusters, fullerenes, and even atoms can be approximated by this spherical-shell model, with R fixed by the true static dipole polarizability. Once t/R is fixed, all the higher coefficients are determined by just C6 and C8. Finally, we compare the exact C2k to those from a pair interaction model, which works for solid spheres (t = R) but not for fullerenes. [ABSTRACT FROM AUTHOR]

We consider ultracold collisions of ground-state heteronuclear alkali-metal dimers that are susceptible to four-center chemical reactions 2AB → A2 + B2 even at submicrokelvin temperatures. These reactions depend strongly on species, temperature, electric field, and confinement in an optical lattice. We calculate ab initio van der Waals coefficients for these interactions and use a quantum formalism to study the scattering properties of such molecules under an external electric field and optical lattice. We also apply a quantum threshold model to explore the dependence of reaction rates on the various parameters. We find that, among the heteronuclear alkali-metal fermionic species, LiNa is the least reactive, whereas LiCs is the most reactive. For the bosonic species, LiK is the most reactive in zero field, but all species considered, LiNa, LiK, LiRb, LiCs, and KRb, share a universal reaction rate once a sufficiently high electric field is applied. For indistinguishable bosons, the inelastic/reactive rate increases as d2 in the quantum regime, where d is the dipole moment induced by the electric field. This is a weaker power-law dependence than for indistinguishable fermions, for which the rate behaves as d6. [ABSTRACT FROM AUTHOR]

We present a theoretical study of the isotope effect arising from the replacement of H by T in the charge-transfer collision H(n = 2) + He+(1s) at low energy. Using a quasimolecular approach and a time-dependent wave-packet method, we compute the cross sections for the reaction including the effects of the nonadiabatic radial and rotational couplings. For H(2s) + He+(1s) collisions, we find a strong isotope effect at energies below 1 eV/amu for both singlet and triplet states. We find a much smaller isotopic dependence of the cross section for H(2p) + He+(1s) collisions in triplet states, and no isotope effect in singlet states. We explain the isotope effect on the basis of the potential energy curves and the nonadiabatic couplings, and we, evaluate the importance of the isotope effect on the charge-transfer rate coefficients. [ABSTRACT FROM AUTHOR]

Abstract: A recent paper [J. Chem. Phys. 132 (2010) 134705] illustrated the potential of the van der Waals density functional (vdW-DF) method [Phys. Rev. Lett. 92 (2004) 246401] for efficient first-principle accounts of structure and cohesion in molecular crystals. Since then, modifications of the original vdW-DF version (identified as vdW-DF1) have been proposed, and there is also a new version called vdW-DF2 [Phys. Rev. B 82 (2010) 081101(R)], within the vdW-DF framework. Here we investigate the performance and nature of the modifications and the new version for the binding of a set of simple molecular crystals: hexamine, dodecahedrane, C60, and graphite. These extended systems provide benchmarks for computational methods dealing with sparse matter. We show that a previously documented enhancement of non-local correlations of vdW-DF1 over an asymptotic atom-based account close to and a few Å beyond binding separation persists in vdW-DF2. The calculation and analysis of the binding in molecular crystals require appropriate computational tools. In this paper, we also present details on our real-space parallel implementation of the vdW-DF correlation and on the method used to generate asymptotic atom-based pair potentials based on vdW-DF. [Copyright &y& Elsevier]

The microwave resonant frequencies of ground-state 87Rb and 133Cs atoms in Xe buffer gas are shown to have a relatively large nonlinear dependence on the Xe pressure, presumably because of RbXe or CsXe van der Waals molecules. The nonlinear shifts for Xe are opposite in sign to the previously measured shifts for Ar and Kr, even though all three gases have negative linear shifts. The Xe data show striking discrepancies with the previous theory for nonlinear shifts. Most of this discrepancy is eliminated by accounting for the spin-rotation interaction, γN · S, in addition to the hyperfine-shift interaction, δA I · S, in the molecules. To the limit of our experimental accuracy, the shifts of 87Rb and 133Cs in He, Ne, and N2 were linear with pressure. [ABSTRACT FROM AUTHOR]

We demonstrated that the weak van der Waals-force-bound argon dimer can be nonadiabatically aligned by nonresonant femtosecond laser pulses, showing periodic alignment and anti-alignment revivals after the extinction of the laser pulse. Based on the measured nonadiabatic alignment trace, the rotational constant of the argon dimer ground state is determined to be B0 = 0.05756?±?0.00004 cm-1. Noticeable alignment dependence of frustrated tunneling ionization and bond-softening induced dissociation of the argon dimer are observed. [ABSTRACT FROM AUTHOR]

Abstract: We have established the cohesive law for interfaces between a carbon nanotube (CNT) and polymer that are not well bonded and are characterized by the van der Waals force. The tensile cohesive strength and cohesive energy are given in terms of the area density of carbon nanotube and volume density of polymer, as well as the parameters in the van der Waals force. For a CNT in an infinite polymer, the shear cohesive stress vanishes, and the tensile cohesive stress depends only on the opening displacement. For a CNT in a finite polymer matrix, the tensile cohesive stress remains the same, but the shear cohesive stress depends on both opening and sliding displacements, i.e., the tension/shear coupling. The simple, analytical expressions of the cohesive law are useful to study the interaction between CNT and polymer, such as in CNT-reinforced composites. The effect of polymer surface roughness on the cohesive law is also studied. [Copyright &y& Elsevier]

Abstract: In this paper, nanoscale modeling of a multi-shell fullerene embedded in an elastic medium and its application to vibrational analysis is investigated. The spherical layers of the multi-shell fullerene are concentrically nested, with carbon–carbon van der Waals interactions between them. Also, the whole multi-shell fullerene is influenced by polymer–carbon van der Waals forces from the surrounding elastic medium. The elasticity generated by the carbon–carbon bonds is assumed to be distributed isotropically over the fullerene surfaces. Following derivation of explicit equations for the motion of the multi-shell fullerene, vibrational behavior of a double-shell fullerene is analyzed and resonant frequencies and the associated mode shapes are determined. [Copyright &y& Elsevier]

In this paper, we introduce a modified Lyapunov vector method for retrieving the leading Lyapunov exponent for a dynamical system with strong nonlinear forces. Performances of the proposed method and the classical QR method are compared. This method is applied to the computation of Lyapunov exponents of a mechanical oscillator under the influence of van der Waals forces. The advantage of this approach lies in the property of preserving the norm of the solution vector. [Copyright &y& Elsevier]

Several time-dependent quantum and hybrid methods are applied to study the dissociation dynamics of tri- and tetra-atomic van der Waals complexes, formed by a diatomic molecule and one or two rare gas atoms. Beginning with “exact” formulations of the wave packet propagation, using grid or channel descriptions, some approximations as reduction of dimensionality or “mean field” treatments are included. Also, hybrid procedures combining either simultaneously or sequentially Classical and Quantum Mechanics, are presented and discussed. [Copyright &y& Elsevier]

• Novel "Diffuse Bounce Back (DBB)" boundary condition is proposed. • DBB utilizes uniform Cartesian grid for flows in complex geometry. • Unlike most uniform Cartesian grid boundary conditions such as Interpolated Bounce Back or Immersed Boundary Methods, DBB is rigorously derived from the weak form of lattice Boltzmann equation. • Grid convergence of DBB and convergence to regular Bounce-back scheme are tested. • Force oscillation around a moving object is shown to be reduced in DBB. The lattice Boltzmann method has been widely used in curved and moving boundary fluid simulations. Both explicit and implicit treatments are studied to recover proper boundary conditions on Cartesian grids. These methods can describe curved boundaries more accurately and more smoothly than the staircase approximation. However, to improve the order of accuracy and to reduce the fluctuation of force, complicated modifications have been applied to the collision step of lattice Boltzmann equation. In this study, a new boundary scheme based on diffuse geometry is proposed for lattice Boltzmann method. The scheme is derived by directly incorporating the bounce back condition into the weak form of the streaming step of discretized Boltzmann equation. The new method does not change the collision operator. Therefore it can be easily combined with complex collision models. Although diffuse boundary is introduced, this scheme recovers exact bounce back condition at sharp boundary limit, regardless of the shapes and motions of the boundaries. Numerical tests show that the accuracy of this method is second order and depends on the boundary thickness and several other factors. In moving boundary problems, the fluctuation of force can be largely reduced compared to popular sharp boundary conditions because it does not require extrapolation to fulfil the unknown information of the newly generated fluid nodes around the boundaries. In this paper the detailed derivation for the new scheme is explained and the benchmark problems are solved to test its accuracy and the effect of different parameters. [ABSTRACT FROM AUTHOR]

SENCALAR/GLASSMAN QUINTET Altin Sencalar, trombone; Chris Glassman, bass trombone; five others Clef DCR-161 (CD). Altin Sencalar and Chris Glassman must now be added to the trombone- badass list. Frei's arrangement contemporizes Trane's modal tenor sax classic and transforms it into a series of trombone fanfares.-Thomas Conrad PHOTO (COLOR). [Extracted from the article]

We investigate the singularity structure of the (-1)F graded partition function in QCD with nf ≥ 1 massive adjoint fermions in the large-N limit. Here, F is fermion number and N is the number of colors. The large N partition function is made reliably calculable by taking space to be a small three-sphere S³. Singularities in the graded partition function are related to phase transitions and to Hagedorn behavior in the (-1)F-graded density of states. We study the flow of the singularities in the complex "inverse temperature" β plane as a function of the quark mass. This analysis is a generalization of the Lee-Yang-Fisher-type analysis for a theory which is always in the thermodynamic limit thanks to the large N limit. We identify two distinct mechanisms for the appearance of physical Hagedorn singularities and center-symmetry changing phase transitions at real positive β, inflow of singularities from the β = 0 point, and collisions of complex conjugate pairs of singularities. [ABSTRACT FROM AUTHOR]

The article discusses the views of Nicola Pugno, a professor at Polytechnic of Turin, Italy, about the use of nanotechnology in human suits. Pugno says that such suits will enable humans to scale vertical walls as spiders do. In those suits, capillary and van der Waals forces, which are used by spiders, will be harnessed, argues Pugno. These forces give molecular attraction between small objects.