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Multi-objective optimization of a solar receiver considering both the dimple/protrusion depth and delta-winglet vortex generators

In this study, multi-objective optimization of the performance of a solar receiver with dimple and delta-winglet vortex generators (DWVGs) is carried out. The thermal performance and outlet dimensionless turbulent kinetic energy (TKE) are chosen as the optimization objectives. The dimple depth, dimple arrangement, the length, height, angle and spacing of the DWVGs are selected as the optimization

Recycling of domestic wastewater treated by vertical-flow wetlands for irrigation of two consecutive Capsicum annuum generations

Due to water scarcity, there is great interest in reusing various nutrient-rich wastewaters. The aim of this article is consequently to evaluate if domestic wastewater treated by various wetland systems can be successfully recycled to irrigate generations of commercial crops such as Chilli (Capsicum annuum) grown in compost within a laboratory environment to obtain a cultivar adapted to domestic w

Dioxidomolybdenum(VI) and -tungsten(VI) complexes with tripodal amino bisphenolate ligands as epoxidation and oxo-transfer catalysts

The molybdenum(VI) and tungsten(VI) complexes [MO2(L)] (M = Mo (1), W (2), H2L = bis(2-hydroxy-3,5-di-tert-butybenzyl)morpholinylethylamine) were synthesized and the complexes were used to catalyze oxotransfer reactions, viz. sulfoxidation, epoxidation and benzoin oxidation. For comparison, the same reactions were catalyzed using the known complexes [MO2(L′)] (M = Mo (3), W (4), H2L′ = bis(2-hydro

Three-dimensional microplate formation with evaporating nanoparticle suspensions on superhydrophobic surfaces

The concept of evaporation driven self-assembly of nanoparticles is exploited to fabricate three dimensional microstructures on textured superhydrophobic surfaces. The evaporative droplets always remain in Cassie–Baxter state during the process of drying. However, the wetting transition from Cassie to Wenzel state has been observed for pure water drop on similar surfaces. After complete evaporatio

Quantifying the effects of land use and climate on Holocene vegetation in Europe

Early agriculture can be detected in palaeovegetation records, but quantification of the relative importance of climate and land use in influencing regional vegetation composition since the onset of agriculture is a topic that is rarely addressed. We present a novel approach that combines pollen-based REVEALS estimates of plant cover with climate, anthropogenic land-cover and dynamic vegetation mo

Anodization of Al(100), Al(111) and Al Alloy 6063 studied in situ with X-ray reflectivity and electrochemical impedance spectroscopy

We present results from the anodization of single crystal Al(100) and Al(111) surfaces and the aluminum alloy AA 6063 studied in situ by X-ray reflectivity and electrochemical impedance spectroscopy. We observe that the anodic oxide layer grows linearly with the anodization potential and that the thicknesses are similar for all samples. However, the thicknesses obtained from X-ray reflectivity are

Experimental and theoretical analysis of in-plane cohesive testing of paperboard

In-plane cohesive failure of paperboard was characterized by short-span uniaxial tension tests. Six paperboards' qualities were experimentally investigated, from which cohesive stress-widening curves were extracted. A fracture energy was defined, expressed in the tensile strength and maximum slope of the cohesive stress-widening relation. Analytical cohesive relations were derived based on the ten

Narrating climate futures : shared socioeconomic pathways and literary fiction

In parallel with five new scientific scenarios of alternative societal developments (shared socioeconomic pathways, SSPs), a wide range of literary representations of a future world in which climate change comes to matter have emerged in the last decade. Both kinds of narrative are important forms of “world-making.” This article initiates a conversation between science and literature through situa

Computational homogenisation for thermoviscoplasticity : application to thermally sprayed coatings

Metal forming processes require wear-resistant tool surfaces in order to ensure a long life cycle of the expensive tools together with a constant high quality of the produced components. Thermal spraying is a relatively widely applied coating technique for the deposit of wear protection coatings. During these coating processes, heterogeneous coatings are deployed at high temperatures followed by q

Chemical changes in organic matter after fungal colonization in a nitrogen fertilized and unfertilized Norway spruce forest

Background and aims: Decomposition and transformation of organic matter (OM) in forest soils are conducted by the concomitant action of saprotrophic and mycorrhizal fungi. Here, we examine chemical changes in OM after fungal colonization in nitrogen fertilized and unfertilized soils from a Norway spruce forest. Methods: Sand-filled bags amended with composted maize leaves were placed in the forest

Reliability Based Design Optimization for Multiaxial Fatigue Damage Analysis Using Robust Hybrid Method

The purpose of the Reliability-Based Design Optimization (RBDO) is to find the best compromise between safety and cost. Therefore, several methods, such as the Hybrid Method (HM) and the Optimum Safety Factor (OSF) method, are developed to achieve this purpose. However, these methods have been applied only on static cases and some special dynamic ones. But, in real mechanical applications, structu

A validation study of an interviewer-administered short food frequency questionnaire in assessing dietary vitamin D and calcium intake in swedish children

Vitamin D and calcium are essential nutrients with a range of biological effects of public health relevance. This study aimed to validate a short food frequency questionnaire (SFFQ) against a three-day food record (3D record), assessing the intake of vitamin D and calcium in Swedish children during wintertime. In a double-blinded, randomized food-based intervention study on the effect of feeding d

Impact of basic angle variations on the parallax zero point for a scanning astrometric satellite

Context. Determination of absolute parallaxes by means of a scanning astrometric satellite such as Hipparcos or Gaia relies on the short-term stability of the so-called basic angle between the two viewing directions. Uncalibrated variations of the basic angle may produce systematic errors in the computed parallaxes. Aims. We examine the coupling between a global parallax shift and specific variati

First evidence of multiple populations along the AGB from Strömgren photometry

Spectroscopic studies have demonstrated that nearly all Galactic globular clusters (GCs) harbour multiple stellar populations with different chemical compositions. Moreover, colour-magnitude diagrams based exclusively on Strömgrem photometry have allowed us to identify and characterise multiple populations along the RGB of a large number of clusters. In this paper we show for the first time that S

Tourism, tourist learning and sustainability : an exploratory discussion of complexities, problems and opportunities

Learning is often a central element of tourism. Tourists can learn actively, i.e. with a specific purpose, as well as passively through the comparison of values, norms and customs. It has been argued that travel supports active learning that has positive outcomes for sustainability, for instance, in the context of conservation. Yet, the complexity of active and passive learning processes and their

The Gaia -ESO Survey : radial distribution of abundances in the Galactic disc from open clusters and young-field stars

Context. The spatial distribution of elemental abundances in the disc of our Galaxy gives insights both on its assembly process and subsequent evolution, and on the stellar nucleogenesis of the different elements. Gradients can be traced using several types of objects as, for instance, (young and old) stars, open clusters, HII regions, planetary nebulae. Aims. We aim to trace the radial distributi

Molecular Dynamic Simulations of Ionic Liquid's Structural Variations from Three to One Layers inside a Series of Slit and Cylindrical Nanopores

We apply molecular dynamic simulations to describe [C2mim+][Tf2N-] ionic liquids and its mixtures with solvents confined inside carbon nanopores. Both slit and cylindrical pores are modeled to determine the influence of pore geometry on the electric double layer (EDL) structure and capacitance. Two types of solvents are selected to dilute the ionic liquids in order to establish the effect of solve

Dynamic Fault-Tolerance and Mobility Provisioning for Services on Mobile Cloud Platforms

We present the implementation of a platform for providing mobility and reliability to computational tasks that are executed in the access cloud. The platform is primarily aimed at providing an experimental tool for further studying of sophisticated techniques for task scheduling, placement and migration policies. In its current form, the platform supports streaming services but can be extended wit