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A giant negative electrocaloric (EC) effect in a PbZrO3/(0.88BaTiO3-0.12 Bi(Mg1/2,Ti1/2)O3) (PZ/(BT-BMT)) multilayered composite ferroelectric (MCFE) thin film which is grown on Pt(111)/Ti/SiO2/Si(100) substrates by the sol-gel method is investigated in this work. The negative EC effect in the PZ/(BMT-BT) MCFE thin film is greatly higher than that in the PZ AFE thin film with an adiabatic temperature change (ATC) ΔT = 1.5 K. The ATC ΔT of the PZ/(BMT-BT) MCFE thin film is -32 K under the applied electric field change ΔE = 1151 kV/cm. The result is conducive to enhance the EC refrigeration efficiency greatly. [ABSTRACT FROM AUTHOR]

This paper describes an investigation of plastic instability of an internally impulsively loaded thin-walled spherical pressure vessel with plastic orthotropy. In the framework of finite deformation and Hill's orthogonal anisotropic yield criterion, the vessel instability strain is derived, which includes the effects of the plastic orthotropy and strain rate. [ABSTRACT FROM AUTHOR]

The vehicle routing problem with split deliveries and pickups is a hot research topic in recent years, where a customer can be served multiple times with split deliveries and pickups. The objective is to minimize the travel distance, use the fewest number of vehicles and increase the load rate, which will further reduce the carbon emissions that damage the environment. In this paper, we use a two-stage construction heuristic approach to solve this problem. First, partitioning algorithms based on the multi-restart-iterative sweep algorithm are adopted to partition the customer domain into sub-domains according to the vehicle capacity, and to determine the split points and the corresponding values. Second, a modified Clarke-Wright savings algorithm is used to check the possibility of each point in each route based on the load of each point and the vehicle load limitation. The three case studies with 12 instances per each from the reconstructed Solomon benchmark datasets were conducted to evaluate the effectiveness and feasibility of the proposed approaches-Unsplit, Both-Split and Enhanced-Both-Split. The comparison among these approaches reveals that the splits reduce the total travel cost and vehicles used, and increase the average loading rate considerably, especially when customers have larger demand values. Our computation results proves that the vehicle routing problem with split deliveries [ABSTRACT FROM AUTHOR]

We carried out high‐resolution Large Eddy Simulations to study the three‐dimensional hydrodynamic characteristics over regular and irregular wave‐generated ripples. Two types of irregularities in ripple crestlines are considered, namely ripples with a termination defect and with a bifurcation defect. Over regular ripples, the flow and vortex structures vary in the spanwise direction, displaying evident three‐dimensional vortex structures. Compared to regular ripples, the presence of a bifurcation or a termination defect implies local variations in ripple height and spacing. As a result, the maximum velocity, vortex strength and the position of the vortex center over ripples neighboring a defect are all affected by the presence of the defect. The maximum velocity at the ripple crest neighboring a defect is linearly related to the position of the vortex center. The presence of defects induces an asymmetric distribution of shear stress and sediment flux that will ultimately affect bedform evolution. Plain Language Summary: Wave‐generated ripples are a ubiquitous pattern present on seafloors and beaches. Because of their regularity and simple shape, ripples capture the attention of the casual observer and have become the focus of many scientists. When looking at a ripple field in detail, it is possible to observe that crestlines are not necessarily straight and continuous, and they often present irregularities usually called "defects." However, researchers still do not know why defects are present and what is their role on ripple evolution. We performed high‐resolution Large Eddy Simulations to study the flow structures over both regular and irregular (because of the presence of defects) ripple geometries. We analyzed the vortex structures, shear stress and possible sediment flux over different types of bedform structures and conclude that defects affect local and neighboring ripples by altering the dynamics of the vortices developing over the bedforms. These results have implications for the evolution of a rippled seabed and its role on frictional effects and sediment transport. Key Points: Three‐dimensional flow structures over defect ripples have been investigated through high‐resolution Large Eddy Simulations modelDefects (bifurcations and terminations) cause local variations on vortex size and positionThe maximum velocity over a ripple crest neighboring a defect is linearly related to the vortex attributes [ABSTRACT FROM AUTHOR]

A number of bimetallic complexes of Ni(II) and Cu-(II) of the type is isolated and characterized. The four ligands are used were bis-amines of\r bis-imines and with both di- or trimethylene links between the nonaromatic nitrogen atoms.