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The electronic band structure, density of states, optical absorption, phonon spectrum, stability, and thermodynamic properties of 1T’-phase RuOsSe₂ hybrid monolayer were systematically studied using ab initio calculations based on Density Functional Theory (DFT) and Density Functional Perturbation Theory (DFPT) within the generalized gradient approximation (GGA) and the HSE06 functional of hybrid correlation–exchange. Indirect bandgaps $E_g=0.68$eV and $E_g=1.23$eV were obtained within the calculation level GGA-PBE and HSE06. The investigation of optical absorption shows that the RuOsSe₂ monolayer exhibits a significant absorption in the ultraviolet and visible regions of the electromagnetic spectrum. Thermodynamic potentials and specific heat at constant volume were calculated, of which dependence on the temperature is discussed. We predict a new RuOsSe₂ monolayer from the 1T’ phase that could potentially be synthesized for future electronic devices and bring potential technological applications.

The study of Drell–Yan (DY) processes involving the collision of an (un)polarised hadron beam on an (un)polarised proton target can result in a fundamental improvement of our knowledge on the transverse momentum dependent (TMDs) parton distribution functions (PDFs) of hadrons. The production mechanism of J/ψ and J/ψ - DY duality can also be addressed. One of the forthcoming polarised DY experiments (COMPASS (SPS, CERN)) is discussed in this context. The most important features of this project are briefly reviewed, as well as its sensitivity to the various transverse momentum dependent spin asymmetries.

New supramolecular hydrogen bonded mesogens are designed with the non-covalent interactions between the two polar groups. Interesting observations made in the synthesis of new hydrogen bonded mesogen between the mesogenic group p-n-alkyl benzoic acid with n representing the alkyl carbon number from pentyl to decyl of benzoic acid group and non-mesogen ortho-toluamide containing nitro group. The thermodynamic properties of the observed textures are studied by polarizing optical microscope and compared with the corresponding differential scanning calorimetry. The results of hydrogen-bonded mesogen are studied in comparison with the free p-n-alkyl benzoic acids. The intermolecular hydrogen bonding between the two polar groups convinced by FT-IR favours the formation of hydrogen-bonded mesogen with crystal G phase different from their constituents.

This paper presents a study on optimization of design parameters and positions of single tuned mass damper (STMD) and multiple tuned mass dampers (MTMDs), used as vibration control systems in buildings under seismic excitations aiming to reduce their story drift. As case studies, three buildings are subjected to three real earthquakes and one non-stationary artificial earthquake, and their responses are analyzed. For each building, different control scenarios are proposed and to run the optimizations, the whale optimization algorithm (WOA) was used. The results showed that for Building 1, the Scenario 1-Optimized, with a STMD at the top floor, was the best alternative. In Building 2, the Scenario 1-Optimized, with also a STMD at the top floor, proved to be the best solution. Finally, for Building 3, the Scenario 4-Modified, with 3 TMDs arranged in the building elevation plane was the only one that had effective control of structural response, therefore, it is the best control scenario.

Liquid storage tanks are widely used in the industrial and the agricultural production, the earthquake damage of the liquid storage tanks will not only lead to economic losses, but also may cause environmental pollution, fire and explosion. Considering the fluid–structure interaction, the liquid sloshing and the material nonlinearity, the three-dimensional numerical calculation models of nondamping and tuned mass damper (TMD) liquid storage tanks are established, respectively. The earthquake waves with different characteristics are selected to investigate the dynamic responses of the liquid storage tank, the control effects of the TMD on the seismic responses of the liquid storage tank are analyzed, and the influence law of the change of the spring stiffness on the damping effect is discussed. The results show that the TMD has a significant damping effect on the liquid storage tank, and the element damping has significant influence on the dynamic responses in the subsequent stage of the earthquake action. Under the action of Darfield–New Zealand wave, the damping ratio corresponding to the acceleration of the tank wall is 69.6%. When the element damping is not considered, the small change of the spring stiffness has significant influence on the damping effect, but after the element damping being considered, the influence of the spring stiffness change on the damping effect is small. The TMD provides a high performance system to the damping control of the liquid storage tank under the action of earthquakes with different intensity.

The effects of relative positions of Se atoms in a monomolecular layer of MoS${}_{1.5}$Se${}_{0.5}$ have been studied. It is demonstrated that the distribution of Se atoms between top and bottom chalcogen planes is most energetically favorable. For a more probable distribution of Se atoms this monolayer alloy is a direct semiconductor with the fundamental bandgap of 2.35eV. We have also evaluated the optical band gaps of the alloy at 77K (1.86eV) and room temperature (1.80eV), which are in a good agreement with the experimentally measured bandgap of 1.79eV.

A recent investigation of the single spin asymmetry (SSA) in low virtuality electroproduction/photoproduction of J/ψ in color evaporation model is presented. It is shown that the asymmetry is sizable and can be used as a probe for the still unknown gluon Sivers function.

The exploration of the structure of the nucleon reaches a new level of sophistication when explicit dependences on transverse momenta of partons in both parton distributions and fragmentation functions are included. These dependences lead to a manifold of new correlations between the nucleon and quark spin as well as their momenta and thus a wealth of experimental observables. A particular example is the novel Sivers function that—according to firm QCD predictions—has to change sign when going from the Drell-Yan process to semi-inclusive deep-inelastic scattering. Here a review is given on which knowledge has been gathered about transverse-momentum-dependent (TMD) distribution and fragmentation functions from semi-inclusive deep-inelastic scattering experiments.

In this brief article we summarize the derivation of the Sivers function of a heavy nucleus, which we obtain by generalizing the quasi-classical McLerran-Venugopalan model to incorporate the role of spin and orbital angular momentum. In doing so we obtain a new channel which is capable of generating the Sivers function of the nucleus from the orbital motion of its nucleons. An essential role is played in this channel by the multiple rescatterings on spectator nucleons which screen the distribution function during the initial- or final-state interactions. The combination of orbital angular momentum together with multiple rescattering yields a new interpretation of the sign flip relation between the Sivers function measured in semi-inclusive deep inelastic scattering and the Drell-Yan process.

We report on the studies of Transverse-Momentum-Dependent distributions (TMDs) at a future fixed-target experiment –AFTER@LHC– using the $p^{+}$ or Pb ion LHC beams, which would be the most energetic fixed-target experiment ever performed. AFTER@LHC opens new domains of particle and nuclear physics by complementing collider-mode experiments, in particular those of RHIC and the EIC projects. Both with an extracted beam by a bent crystal or with an internal gas target, the luminosity achieved by AFTER@LHC surpasses that of RHIC by up to 3 orders of magnitude. With an unpolarised target, it allows for measurements of TMDs such as the Boer-Mulders quark distributions and the distribution of unpolarised and linearly polarised gluons in unpolarised protons. Using polarised targets, one can access the quark and gluon Sivers TMDs through single transverse-spin asymmetries in Drell-Yan and quarkonium production. In terms of kinematics, the fixed-target mode combined with a detector covering ${\eta }_{\mathrm{\text{lab}}}\in [1,5]$ allows one to measure these asymmetries at large $x^{\uparrow }$ in the polarised nucleon.

Weeks V and VI of the INT program 2018 were dedicated to physics opportunities at a future Electron-Ion Collider. Discussions were wide ranging and included topics such as short-range correlation, jets physics in deep inelastic scattering, nuclear PDFs, TMDs, and GPDs as well as small-x helicity distributions, non-linear small-x evolution equations, diffraction and particle production and correlations.

Transverse spin and transverse momentum distribution functions of the constituents of the nucleon are a crucial input for a complete description of the nucleon. COMPASS measured such for longitudinally and transversely polarized deuterons and protons. In the following we will focus on recent results from the 2007 transverse proton data and on the results for unpolarized deuterons.