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In recent years, essential oils (EOs) have received increased attention from the research community, and the EOs of cinnamon, patchouli, and geranium have become highly recognized for their antibacterial, antifungal, antiviral, and antioxidant effects. Due to these properties, they have become valuable and promising candidates for addressing the worldwide threat of antimicrobial resistance and other diseases. Simultaneously, studies have revealed promising new results regarding the effects of physical fields (magnetic and electric) and LASER (MEL) exposure on seed germination, plant growth, biomass accumulation, and the yield and composition of EOs. In this frame, the present study aims to investigate the influence of MEL treatments on cinnamon, patchouli, and geranium EOs, by specifically examining their composition, antimicrobial properties, and antioxidant activities. Results showed that the magnetic influence has improved the potency of patchouli EO against L. monocytogenes, S. enteritidis, and P. aeruginosa, while the antimicrobial activity of cinnamon EO against L. monocytogenes was enhanced by the electric and laser treatments. All exposures have increased the antifungal effect of geranium EO against C. albicans. The antioxidant activity was not modified by any of the treatments. These findings could potentially pave the way for a deeper understanding of the efficiency, the mechanisms of action, and the utilization of EOs, offering new insights for further exploration and application. [ABSTRACT FROM AUTHOR]

We present theoretical investigations examining the electronic and magnetic properties of the SmFe12−xMox (x = 1, 2) and SmFe10Mo2H compounds, including magneto-crystalline anisotropy, magnetic moments, exchange-coupling parameters, and Curie temperatures. The spin-polarized fully relativistic Korringa–Kohn–Rostoker (SPR-KKR) band structure method has been employed, using the coherent potential approximation (CPA) to deal with substitutional disorder. Hubbard-U correction was applied to the local spin density approximation (LSDA+U) in order to account for the significant correlation effects arising from the 4f electronic states of Sm. According to our calculations, the total magnetic moments increases with H addition, in agreement with experimental data. Adding one H atom in the near-neighbor environment of the Fe 8j site reduces the magnetic moments of Fe 8j and enhances the magnetic moment of Fe 8f. For every investigated alloy, the site-resolved spin magnetic moments of Fe on the 8i, 8j, and 8f sites exhibit the same magnitude sequence, with m s F e (8i) > m s F e (8j) > m s F e (8f). While the addition of H has a positive impact on magneto-crystalline anisotropy energy (MAE), the increase in Mo concentration is detrimental to MAE. The computed exchange-coupling parameters reveal the highest values between the closest Fe 8i spins, followed by Fe 8i and Fe 8j spins, for all investigated alloys. The Curie temperature of the alloys under investigation is increased by decreasing the Mo concentration or by H addition, which is qualitatively consistent with experimental findings. [ABSTRACT FROM AUTHOR]

Petroleum is the most important resource for global energy production, far exceeding the role of coal and natural gas, the role of river energy and wind energy, and also the role of nuclear fuel.

Today the world is facing, more and more, different sources of pollution, the most affected areas being the proximity of big industrial centers (e.g.: chemistry, mining and metallurgy, machinery building etc.). Baia Mare industrial area is a typical one for such a situation. To maintain a clean and healthy environment in Baia Mare city and in the surrounding areas, important costs are needed. The usefulness of the mathematical models consists in the possibility of mathematical processing of industrial parameters evolutions, with relevant interpretations on various influences and their correction for achieving the set goals (maximizing financial efficiency, environmental protection with the compliance of legal requirements etc.)

The intrinsic magnetic properties (magnetic moments, magneto-crystalline anisotropy, Curie temperatures) of the (Fe1−xMx)2B alloys have been calculated using the spin-polarized relativistic Korringa–Kohn–Rostoker (SPR-KKR) band structure method. The transition metal elements M (M = Co, Ni, Mo, Ta, W and Re) considered in the present study are reported to form stable M2B or FeMB alloys with a tetragonal Cu2Al structure type. The experimental studies show that the Fe2B alloy has a large magnetization (173 Am2/kg), a large Curie temperature (1017 K) and a relatively large anisotropy constant K1 (−0.80 MJ/m3), but the alloy is inappropriate for permanent magnet applications due to in-plane easy magnetization axis (EMD). The present investigations show the magnetocrystalline anisotropy behaviour by doping with selected d-elements aiming to find an appropriate dopant which is able to switch the EMD from planar to axial and to enhance the magnetocrystalline anisotropy energy (MAE) value without a major decrease of magnetization and Curie temperature. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to investigate the behavior of mechanically milled Nd2Fe14B powders. The effect of the milling on the magnetic properties of the Nd2Fe14B intermetallic is measured and is compared to the structural analysis performed by Mössbauer spectroscopy and atom probe tomography (APT). The high energy ball milling of Nd2Fe14B powders for up to 12 h induces the progressive disappearance of the hard magnetic behavior. Mössbauer spectroscopy and APT analyses have shown the decomposition of the Nd2Fe14B phase in the early stages of milling into an amorphous, disordered Nd-Fe-B phase that is rich in neodymium and in an α-Fe phase. The corresponding microstructure is very characteristic, with the formation of submicrometric pure iron particles, surrounded by an amorphous shell enriched in neodymium and in boron. By using APT, each step of the process can be identified. This high-resolution technique allows us obtaining a 3D mapping in real space of the chemical species (Nd, Fe, and B) on the atomic scale. Three-dimensional reconstructions of the nanostructure of the analyzed samples are realized from the data and show the formation of the Nd2Fe14B nanocomposite that is composed of α-Fe soft magnetic nanosized crystallites embedded in the Nd2Fe14B hard magnetic matrix. These results confirm the decomposition of the initial Nd2Fe14B phase. After 2 h of high-energy mechanical milling, Fe particles with diameters of up to 100 nm are observed. By increasing the milling time, the element intermixing and grain size reduction of the decomposition products can be observed. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate the possibility of using a soluble ceramic material, 5 wt% CaO, as an additive for an SmCo5/20wt%Fe exchange-coupled nanocomposite obtained by mechanical milling in order to inhibit the grain growth of the soft magnetic phase during annealing, which results in a more stable microstructure and an implicit improvement in the hard–soft interphase exchange coupling. Moreover, we show that the additive improves the phase stability of the composite material, reducing the amount of Sm2Co17-type phases formed during the synthesis process, an important aspect because Sm2Co17 is detrimental to the magnetic performance of the SmCo5/20%Fe nanocomposite. These effects are reflected in a nearly 13% increase in the coercive field (Hc) and a 20% increase in the energy product, (BH)max, for the powders produced using CaO as compared to pure SmCo5/20%Fe nanocomposites processed in the same manner. [ABSTRACT FROM AUTHOR]

The microstructure of mechanically milled Nd2Fe14B, SmCo5/Fe and SmCo3Cu2/α-Fe alloys has been investigated by Mössbauer spectrometry and atom probe tomography. The structural changes that occur upon milling and subsequent annealing were characterised at a nanometer scale. Milling promotes intermixing of the elements and the formation of nanograins. In Nd-Fe-B powders, the Nd2Fe14B phase is transformed into α-Fe and an amorphous Nd-Fe-B phase. In SmCo5/Fe powders, Fe/Co intermixing occurs, leading to the formation of Sm(Co,Fe)5 and α-Fe(Co) phases. In SmCo3Cu2/Fe powders, although Sm is partly oxidised, Fe/Co intermixing occurs as well, leading to the formation of α-Fe(Co) nanograins surrounded by Sm(Co,Cu,Fe)5 intergranular regions. The combined Mössbauer and atom probe tomography investigation of rare earth / transition metal powders thus allows revealing the effect of mechanical milling and subsequent annealing on the nanostructure of the powders. These results are helpful for the understanding of the magnetic properties of the powders. [ABSTRACT FROM AUTHOR]

The ac susceptibilities of NdFe11Ti and NdFe11TiH, both of which crystallize with the I4/mmm tetragonal ThMn12-type structure, have been measured between 20 and 300 K and the results reveal spin reorientations at ∼185 K and at 100±1 K, respectively. The Mössbauer spectra of NdFe11Ti and NdFe11TiH have also been measured between 4.2 and 295 K and fits of the observed line shape profiles indicate that the spin-reorientations in both compounds correspond to a rotation from an axial orientation to a canted or basal orientation upon cooling. Both the low temperature canted or basal magnetic structures and the lowering of the spin-reorientation temperature upon hydrogenation result from the competing neodymium and iron magnetic anisotropies and differing relative second-, fourth-, and sixth-order contributions as a function of temperature and hydrogen content of the neodymium to the magnetic anisotropy energy. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The magnetic properties of NdFe11Ti and NdFe11TiH are determined through combined ac magnetic susceptibility, thermomagnetic, and iron-57 Mossbauer spectral studies. The results indicate that NDFe11Ti and NdFe11TiH undergo a spin-reorientation transition at tilde 185 K and at 100 plusmn 1 K, respectively, from an axial magnetic phase at higher temperatures to a canted or basal magnetic phase at lower temperatures.

Detailed investigations on the electronic and magnetic properties of the Heusler compounds Mn2− xCu xVAl with L21 structure have been performed. Polycrystalline samples have been examined by X-ray diffraction and magnetization measurements have been performed. The degrees of the B2 and L21 atomic ordering obtained from the intensity ratios of the X-ray patterns have been determined. The Curie temperatures decrease with Cu content, ranging between 771 K ( x = 0) and 580 K ( x = 0.5). Additionally, electronic band structure calculations using the Korringa-Kohn-Rostoker (KKR) Green's function method have been performed. The substitutional disorder was accounted by the means of the Coherent Potential Approximation (CPA). The site occupation considered in the calculations has been correlated with those obtained by the X-ray experiments. Our study is giving an insight on the evolution of the half-metallic fully compensated ferrimagnet (HMFi) character with disorder and Cu doping showing restrictions in obtaining of a HMFi by doping with 3d metals. [ABSTRACT FROM AUTHOR]

Energy is an essential factor regarding the economic development and for providing a high standard of living to the population of any country. Because energy is produced mainly using classic fuels (coal, oil and gas) for a few decades there are signals regarding their exhaustion. Therefore, mankind should concern more about finding viable alternatives to replace the classical fuels. This way the use of nuclear fuels appeared, then the force of the wind, of the tides and of the photovoltaic cells. However, there are still enough energy resources for further growth of the global energy production. The great consumers are both the major energy producers, only their hierarchy has changed and changes over time. The paper presents all these countries, and also Romania, including its specific developments in recent years. [ABSTRACT FROM AUTHOR]

Unemployment is one of the most serious problems of the contemporary world, fact which is expressed not only by all European statistics, statistics showing a growing number of unemployed, despite the consistent concern of the governments of all developed countries. Worse is that the unemployment is the highest among young people up to 25 years, many of them being university graduates. This way the trend of young people to stop attending studies appeared ... seeing as useless their efforts to invest in their future through university studies, the chances of finding a job are minimal despite their diplomas. Hence the name of "the lost generation" - the way that young people are called nowadays. The market economy, based mainly on private property is not considering social issues, it pursues just one goal: profit, more exactly the profit maximization. [ABSTRACT FROM AUTHOR]

The Paris Agreement on climate change issues was adopted at the COP.21 of December 12, 2015. Representatives from 195 countries have agreed to undertake concrete measures in order to contain the rise of global atmospheric temperatures until the end of the century, to less than 2 degrees Celsius in comparison to preindustrial era values. As a way to boost its enactment, the agreement provides that developed countries undertake a yearly 100 billion dollars financing in Eco-friendly technologies directed to developing countries. This paper, other than being a brief listing of Summits dealing with climate change issues also describes the evolution of the CO2 atmosphere percentage as well as the consumption of carbon based fuels - the reason for the highly increasing raise in the concentration of the most nominated greenhouse effect gas that causes the rise of temperature on our planet. [ABSTRACT FROM AUTHOR]

The recent interest in the field of bioplastics is to obtain packaging material from pure starch without synthetic polymers. The rheological behaviour represents one of the most important feature of such materials. Samples with different ratio of starch, glycerol and water were prepared and investigate regarding their rheological behaviour. After the samples reaches their limit of swelling and were completely decomposed viscosity was measured with a Brookfield DV-III Ultra rheometer at different temperatures and share rates. The data were analyzed with Kaleidagraph software. For a given sample our measurements show that the viscosity is dependent on share rate and switches from a non-Newtonian to a Newtonian behaviour in function of temperature and sample composition. We used the power law model to describe this dependence and for a given set of data there is only one output for the fit parameters. We consider the best fit of the experimental data when the curve traced by the computer passes almost through all experimental points. In the present research work we establish a particular algorithm of mathematical analysis of experimental data which allows a separation of the contribution of each variable to the viscosity. [ABSTRACT FROM AUTHOR]