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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.

The current study was carried out to monitor the dynamics of phenolic compounds and vitamin C variations in Hippophae rhamnoides L. (sea buckthorn) under the influence of different color filters, as follows: yellow (590 nm), blue (450 nm), and violet (400 nm). The fruits were harvested at maturity from different parts of the canopy (i.e., base, middle, and top), immediately stored at −18 °C, and afterward lyophilized to reduce the loss of compounds for preparing the chemical assays that were carried out. HPLC-DAD-ESI+ was used to determine the phenolic compounds and vitamin C content of the fruits. EPR (electron paramagnetic resonance) measurements were also carried out to confirm the antioxidant character of the berries. This is the first study to examine the effect of different color filters on the accumulation of phenolic compounds and vitamin C content in the fruits of sea buckthorn. Among the three color filters used, the violet filter proved to be the most beneficial for the accumulation of total phenolic compounds (3.326 mg/g) and vitamin C (1.550 mg/g) in the berries. To reach high contents of phenolic compounds and vitamin C, the best setup included using very-high-energy emission LEDs as close as possible to blue and violet (400–450 nm). Therefore, the different light color intensities and temperatures on each level of a canopy play key roles in enhancing the phenolic compound content, antioxidant activity, and vitamin C content of sea buckthorn fruits. This knowledge will help provide insights into the accumulation of secondary metabolites and improve future production strategies in sea buckthorn. [ABSTRACT FROM AUTHOR]

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]

Salinity is one of the most critical abiotic stresses affecting various physiological, biochemical, and molecular functions of plants. This study aimed to assess the effects of different salt concentrations on in vitro blueberry shoots ('Bluecrop', 'Blueray', 'Brigitta Blue', 'Duke', 'Goldtraube', 'Hortblue Petite', and 'Patriot' cultivars) and to understand the mechanisms employed by this species under saline conditions. The Woody Plant Medium (WPM) proliferation medium was supplemented with 10, 50, 100, and 150 mM NaCl to induce salt stress. After ten weeks of in vitro culture under salinity stress, various parameters were evaluated, including the number of shoots obtained/explant, shoot length, fresh weight, dry weight, water content, stress tolerance index (STI), and McKinney index (MKI). Additionally, the behaviour of blueberry cultivars under salt stress was analysed using electron paramagnetic resonance spectroscopy (EPR). Compared to the control (culture medium without NaCl), all treatments with NaCl reduced shoot length and the number of shoots obtained/explant in all studied blueberry cultivars. 'Brigitta Blue' reported the shortest shoots (0.04 ± 0.02 cm) at a concentration of 150 mM NaCl, followed by 'Blueray' with 0.05 ± 0.03 cm. Also, the lowest number of shoots/explant was recorded for both cultivars under 150 mM NaCl, namely 0.12 ± 0.07 shoots/explant ('Brigitta Blue') and 0.11 ± 0.04 shoots/explant ('Blueray'). Salt tolerance, as expressed by ITS and MKI, confirmed that 'Goldtraube' exhibited higher salt tolerance, with the highest ITS values and the lowest MKI values. Further validation presented 'Goldtraube' as the most unresolved spectra of the Mn (II) hyperfine structure under all salt concentrations, therefore 'Goldtraube' was the most tolerant to saline stress. [ABSTRACT FROM AUTHOR]

The paper is part of the interdisciplinary recent concerns of "environmental management", looking to determine the damages caused by pollution, remediation expenditures, and benefits that may arise through the application of remediation techniques and decontamination technologies in the mining and metallurgical Maramureş area. Large areas of land were diverted from their original destination (pastures, arable land, forests) being now covered with ponds and dumps of mine or flotation tailings, deposits that are insufficiently protected, and have become sources of pollution to surrounding areas. All Eastern European countries have in common major environmental problems, the most serious being due to mining, metallurgy and chemistry. In the relationship of "economic-ecological" equilibrium, should be considered both economic criteria, as well as ecological ones. Pollution as the deterioration of environment, requires costs for rehabilitation of degraded areas, and for environmental protection, costs for new technologies, non polluting ones. The assessment foundation of environmental damages, is necessary for establishing the priority directions in the allocation of funds for projects to protect and rehabilitate the environment. [ABSTRACT FROM AUTHOR]

Today more and more the world is facing different sources of pollution, the most affected areas being the proximity of the biggest industrial centres (e.q: chemistry, mining and metallurgy, machine building etc.). The industrial area of Baia Mare is a typical one for such a situation. To maintain a clean and healthy environment in Baia Mare and the surrounding areas, important financial costs are necessary. In terms of European Union accession, demands on environmental protection have also increased, aspect that was unfortunately neglected until now in Romania. Will local community be able to support these costs? Or, finally, all the responsible pollutants will be closed down. [ABSTRACT FROM AUTHOR]

The progressive nature of scientific research is probably the most impressive example that can be given for the term of "progress", together with the belief that subsequent ages are improvements of the previous ones. Economic analysis of technical progress is to determine the effects of the use of new production methods, upon the performance of the economy. Technical progress, the result of research and development activity, is measured by productivity gains and by increasing the quality of the products. Technical progress can also determine the relative decrease of the price of the new goods, causing the increase of profitability and consumer benefits. Competition motivates companies in developing new products and new technologies for producing goods, less expensive. Innovation is not limited to the adoption of new technology, being the process by which technology is developed step by step, until production structures of the company acquire their new performance features, thus providing variety and higher quality of the products and remarkable fact, more accessible to the average consumer. [ABSTRACT FROM AUTHOR]

Nanocrystalline Supermalloy powders were obtained by wet milling in argon atmosphere. As process control agent the C6 H6 was used. Several milling times have been used ranging from 2 up to 20 h. The formation of the alloy was evidenced by X-ray diffraction (XRD). An annealing at 623 K for 4 h was applied in order to remove the internal stresses and to finish the solid state reaction. A typical crystallite size of 11-12 nm has been obtained after 20 h of wet milling. The magnetic measurements have been performed in a magnetic field up to 8 T at 300 K. A decrease of magnetization is observed upon increasing the milling time due both to the defects induced during the milling and to adsorbed benzene on the particles surface. Differential scanning calorimetry (DSC) curves show the exothermic peaks correlated with the presence of the C6 H6 on the powder particles. The benzene and the internal stresses and crystalline defects are eliminated and an increase of magnetization with milling time can be observed for samples annealed at 623 K for 4 h. [ABSTRACT FROM AUTHOR]

(Pr,Dy)2Fe14B/α-Fe hard/soft nanocomposites were obtained by mechanical milling and subsequent annealing. The influence of the milling and annealing conditions on the structural, microstructural and magnetic properties of (Pr0.92Dy0.08)2Fe14B/α-Fe nanocomposite have been investigated. The crystallites mean size was deduced from the Full - Width - at - Half - Maximum - FWHM of the diffraction a-Fe peaks according to Scherrer's formula. The crystallites mean size, for the iron phase, increases when increasing the annealing temperature. [ABSTRACT FROM AUTHOR]

The scientific interest regarding MnBi hard magnetic phase results from the high magnetocrystalline anisotropy of low-temperature phase (LTP) and large Kerr rotation angle of quenched high temperature phase (QHTP). The MnBi phase was obtained by melting of elemental Mn and Bi components. The sample obtained after melting were annealed at different temperatures: 258 °C, 300 °C, 400 °C and 420 °C under vacuum (10-5 mbar). The X-ray patterns show a better cristallinity of the structure after annealing. In both as melt and annealed samples some quantity of free Bi phase was evidenced due to hard diffusion of the elemental components in MnBi matrix. The magnetic coercivity is reinforced by increasing the temperature and a value μ0H ≈ 2.5 T was obtained at 450 K for melted samples and subsequently milled for 2 h and annealed at 300 °C. In order to test the influence of milling on the MnBi phase stability, the as melted samples and the annealed samples were mechanically milled. The quantity of the unreacted Bi phase increases after milling. [ABSTRACT FROM AUTHOR]

X-ray photoelectron spectroscopy (XPS), magnetization and magnetic susceptibility of Mn1− x Al x (x = 0.0, 0.2, 0.4, 0.5, 0.6, 0.7) alloys are reported. X-ray diffraction measurements showed that all investigated samples have the same crystallographic structure as the parent compound (AuCu3-structure type). The alloys are disordered for x ≤ 0.5, but become almost crystallographically ordered for higher Al concentration. This change in the crystallographic order is reflected both in the magnetization and Curie temperature values. The exchange interaction is ferromagnetic between the pairs of the near-neighbour Mn-Ni and Ni-Ni magnetic moments and antiferromagnetic for Mn-Mn pairs. The last one is present only in the disordered alloys, which leads to smaller values of the magnetization of these alloys in comparison with the ordered ones. The Mn magnetic moment has the fully ordered value of 3.2 μB in all investigated alloys. The decrease of the Ni magnetic moment as the Al concentration increases may be explained by the hybridization of the Ni 3d and Al 3sp states, which leads to a partial filling of the Ni 3d band. The magnetic susceptibility measurements pointed out the existence of spin fluctuations on Ni sites. [ABSTRACT FROM AUTHOR]

Nanostructured alloy powders of SmCo5 + 10 wt% Fe obtained using recycled material were studied for the first time. The SmCo5 precursor was obtained from commercial magnets recycled by hydrogen decrepitation. The results were compared with identically processed samples obtained using virgin SmCo5 raw material. The samples were synthesized by dry high-energy ball-milling and subsequent heat treatment. Robust soft/hard exchange coupling was observed—with large coercivity, which is essential for commercial permanent magnets. The obtained energy products for the recycled material fall between 80% and 95% of those obtained when using virgin SmCo5, depending on milling and annealing times. These results further offer viability of recycling and sustainability in production. These powders and processes are therefore candidates for the next generation of specialized and nanostructured exchange-coupled bulk industrial magnets. [ABSTRACT FROM AUTHOR]