Obtaining and Characterization of Vitroceram by Chemical Doped ZnO for Art Mosaic

This paper presents the obtaining and the characterization of ZnO doped vitroceramic, used as photo and termoresistive pigment for art mosaic. The coprecipitation involves two sequential steps, first of ions Zn2+(aq), Cr3+(aq), Co3+(aq) and Mn3+(aq), as oxihydroxides in predetermined molar reports: 98:0,6:0,7:06, followed by maturation, forced filtration and redispersion of the granules in distilled water, after which, by ion exchange is precipitated as intergranular film of Sb3+(aq) and Bi3+(aq) ions. After forced filtration and drying, the material is subjected gradually to a thermal process, according to a curve with three levels: 20-110 °C, 110-360 °C şi 360-950 °C, with a heating rate of 3 °C/min., each level keeping a constant temperature while varying between 4 and 8 h for nanostructures processes of crystalls reform. The vitroceramic was characterized by SEM-EDX, microFTIR and termic derivatography, after treatment at 110 °C and respectively 950 °C, underlining uniformity of grains and revealing their heterojonctional structure in cross-section

The representation of the trade winds in ECMWF forecasts and reanalyses during EUREC4A

The characterization of systematic forecast errors in lower-tropospheric winds is an essential component of model improvement. This paper is motivated by a global, long-standing surface bias in the operational medium-range weather forecasts produced with the Integrated Forecasting System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF). Over the tropical oceans, excessive easterly flow is found. A similar bias is found in the western North Atlantic trades, where the EUREC 4 A field campaign provides an unprecedented wealth of measurements. We analyze the wind bias in the IFS and ERA5 reanalysis throughout the entire lower troposphere during EUREC4 A. The wind bias varies greatly from day to day, resulting in root mean square errors (RMSEs) up to 2.5 m s(-1), with a mean wind speed bias up to -1 m s(-1) near and above the trade inversion in the forecasts and up to -0.5 m s(-1) in reanalyses. These biases are insensitive to the assimilation of sondes. The modeled zonal and meridional winds exhibit a diurnal cycle that is too strong, leading to a weak wind speed bias everywhere up to 5 km during daytime but a wind speed bias below 2 km at nighttime that is too strong. Removing momentum transport by shallow convection reduces the wind bias near the surface but leads to stronger easterly near cloud base. The update in moist physics in the newest IFS cycle (cycle 47r3) reduces the meridional wind bias, especially during daytime. Below 1 km, modeled friction due to unresolved physical processes appears to be too strong but is (partially) compensated for by the dynamics, making this a challenging coupled problem

Impacts of parameterized orographic drag on the Northern Hemisphere winter circulation

A recent intercomparison exercise proposed by the Working Group for Numerical Experimentation (WGNE) revealed that the parameterized, or unresolved, surface stress in weather forecast models is highly model-dependent, especially over orography. Models of comparable resolution differ over land by as much as 20% in zonal mean total subgrid surface stress (Ttot). The way Ttot is partitioned between the different parameterizations is also model-dependent. In this study, we simulated in a particular model an increase in Ttot comparable with the spread found in the WGNE intercomparison. This increase was simulated in two ways, namely by increasing independently the contributions to Ttot of the turbulent orographic form drag scheme (TOFD) and of the orographic low-level blocking scheme (BLOCK). Increasing the parameterized orographic drag leads to significant changes in surface pressure, zonal wind and temperature in the Northern Hemisphere during winter both in 10 day weather forecasts and in seasonal integrations. However, the magnitude of these changes in circulation strongly depends on which scheme is modified. In 10 day forecasts, stronger changes are found when the TOFD stress is increased, while on seasonal time scales the effects are of comparable magnitude, although different in detail. At these time scales, the BLOCK scheme affects the lower stratosphere winds through changes in the resolved planetary waves which are associated with surface impacts, while the TOFD effects are mostly limited to the lower troposphere. The partitioning of Ttot between the two schemes appears to play an important role at all time scales

Why is it so difficult to represent stably stratified conditions in numerical weather prediction (NWP) models?

In the 1990s, scientists at European Centre for Medium-Range Weather Forecasts (ECMWF) suggested that artificially enhancing turbulent diffusion in stable conditions improves the representation of two important aspects of weather forecasts, i.e., near-surface temperatures and synoptic cyclones. Since then, this practice has often been used for tuning the large-scale performance of operational numerical weather prediction (NWP) models, although it is widely recognized to be detrimental for an accurate representation of stable boundary layers. Here we investigate why, 20 years on, such a compromise is still needed in the ECMWF model. We find that reduced turbulent diffusion in stable conditions improves the representation of winds in stable boundary layers, but it deteriorates the large-scale flow and the near-surface temperatures. This suggests that enhanced diffusion is still needed to compensate for errors caused by other poorly represented processes. Among these, we identify the orographic drag, which influences the large-scale flow in a similar way to the turbulence closure for stable conditions, and the strength of the land-atmosphere coupling, which partially controls the near-surface temperatures. We also take a closer look at the relationship between the turbulence closure in stable conditions and the large-scale flow, which was not investigated in detail with a global NWP model. We demonstrate that the turbulent diffusion in stable conditions affects the large-scale flow by modulating not only the strength of synoptic cyclones and anticyclones, but also the amplitude of the planetary-scale standing waves

On the quantum, classical and total amount of correlations in a quantum state

We give an operational definition of the quantum, classical and total amount of correlations in a bipartite quantum state. We argue that these quantities can be defined via the amount of work (noise) that is required to erase (destroy) the correlations: for the total correlation, we have to erase completely, for the quantum correlation one has to erase until a separable state is obtained, and the classical correlation is the maximal correlation left after erasing the quantum correlations. In particular, we show that the total amount of correlations is equal to the quantum mutual information, thus providing it with a direct operational interpretation for the first time. As a byproduct, we obtain a direct, operational and elementary proof of strong subadditivity of quantum entropy.Comment: 12 pages ReVTeX4, 2 eps figures. v2 has some arguments clarified and references update

Impacts of orography on large-scale atmospheric circulation

Some of the largest and most persistent circulation errors in global numerical weather prediction and climate models are attributable to the inadequate representation of the impacts of orography on the atmospheric flow. Existing parametrization approaches attempting to account for unresolved orographic processes, such as turbulent form drag, low-level flow blocking or mountain waves, have been successful to some extent. They capture the basic impacts of the unresolved orography on atmospheric circulation in a qualitatively correct way and have led to significant progress in both numerical weather prediction and climate modelling. These approaches, however, have apparent limitations and inadequacies due to poor observational evidence, insufficient fundamental knowledge and an ambiguous separation between resolved and unresolved orographic scales and between different orographic processes. Numerical weather prediction and climate modelling has advanced to a stage where these inadequacies have become critical and hamper progress by limiting predictive skill on a wide range of spatial and temporal scales. More physically-based approaches are needed to quantify the relative importance of apparently disparate orographic processes and to account for their combined effects in a rational and accurate way in numerical models. We argue that, thanks to recent advances, significant progress can be made by combining theoretical approaches with observations, inverse modelling techniques and high-resolution and idealized numerical simulations

Childbearing intentions in a low fertility context: the case of Romania

This paper applies the Theory of Planned Behaviour (TPB) to find out the predictors of fertility intentions in Romania, a low-fertility country. We analyse how attitudes, subjective norms and perceived behavioural control relate to the intention to have a child among childless individuals and one-child parents. Principal axis factor analysis confirms which items proposed by the Generation and Gender Survey (GGS 2005) act as valid and reliable measures of the suggested theoretical socio-psychological factors. Four parity-specific logistic regression models are applied to evaluate the relationship between the socio-psychological factors and childbearing intentions. Social pressure emerges as the most important aspect in fertility decision-making among childless individuals and one-child parents, and positive attitudes towards childbearing are a strong component in planning for a child. This paper also underlines the importance of the region-specific factors when studying childbearing intentions: planning for the second child significantly differs among the development regions, representing the cultural and socio-economic divisions of the Romanian territory

Numerical and experimental transition results evaluation for a morphing wing and aileron system

A new wing-tip concept with morphing upper surface and interchangeable conventional and morphing ailerons was designed, manufactured, bench and wind tunnel tested. The development of this wing tip model was performed in the frame of an international CRIAQ project, and the purpose was to demonstrate the wing upper surface and aileron morphing capabilities in improving the wing tip aerodynamic performances. During numerical optimization with ‘in-house’ genetic algorithm software, and during wind tunnel experimental tests, it was demonstrated that the air flow laminarity over the wing skin was promoted, and the laminar flow was extended with up to 9% of the chord. Drag coefficient reduction of up to 9% was obtained when the morphing aileron was introduced

Studii asupra unor vinuri de Aligoté obtinut prin diferite tehnologii de vinificaţie

The influence the fermentation volumes have on the sensory profile of the final productis very important.Aligoté grapes from Bucium viticultural center, Iasi vineyardwere used. After crushing, destemming and pressing, the marc was divided into containers of various volumes, from 25 L demijohns to 1000 L tanks. Various selected yeasts was innoculated. For the organoleptic annalysis of wines obtained by the fermenting Aligoté musts, a sensory analysis was organized for each wine assortment.The wines obtained in the industrial system show notes of fresh cut grass and hay and more pronounced notes of green fruits, with a stronger minerality. The texture and persistence of the wines obtained at small scale production are more obviou