In this work, the influence of different deposition angles on the structural,
chemical and magnetic properties of nickel (Ni) thin films was investigated.
Nickel samples were deposited by glancing ...angle deposition technique at two
different angles, 65o and 85o. Characterization of the thin films was
carried out by scanning electron microscopy, X-ray photoelectron
spectroscopy and magneto-optical Kerr effect microscopy. Structural analysis
was found that the changes in the deposition angle have a great influence on
the porosity of the film as well as on the amount of the present nickel
oxide (NiO) in the samples. On the other hand, we have also found that
different deposition angle changes the magnetic response of nickel film. The
coercivity of the samples deposited at the angle of 85o is significantly
higher compared to the samples deposited at lower angle which could be
correlated with the higher porosity and the amount of NiO in the thin films.
In this study, nickel (Ni) thin films were deposited at two different angles
(65o and 85o) using Glancing Angle Deposition technique, to the thicknesses
of 60 - 290 nm. Structural analysis of the ...deposited films was performed by
scanning electron microscopy and X-ray diffraction, while spectroscopic
ellipsometry was used for the investigation of optical properties.
Electrical resitivity of the samples was determined by four-point probe
method. Structural analysis showed that the Ni films grow in a shape of
zigzag nanocolumns, where the deposition angle strongly affects their
porosity. As the thickness of the films increase they absorb light strongly
and become less dense. Besides, samples deposited at the angle of 85o
exhibit higher values of electrical resistivity as compared to the samples
deposited at the angle of 65o, which can be correlated with high porosity
and the growth mechanism of the deposited nanostructures.
Rutting measurements are a significant part of scientific research on the impact of forest vehicles on the forest soils and damage to the forest transport infrastructure. Although photogrammetric ...methods of measurement or measurements based on LiDAR (light detection and ranging) data are increasingly being used for rutting measurements, the previous research conducted using these methods indicated the challenge of recording water-filled ruts. For this reason, it is necessary to define a reliable method of rutting field measurement in lowland forest stands characterized by a high level of groundwater that fills the ruts shortly after the passage of forest vehicles. This research analyzed the measurement accuracy using a total station and a GNSS RTK device with a CROPOS correction base in relation to the measuring rod that represented the reference method. Based on recorded and processed data, ruts are displayed in two ways: as net and as gross value of rut depth. The analysis of net rutting revealed a statistically significant difference between the calculated rut depths based on measurements with a GNSS RTK device and other methods. On average, the net rutting measured by the GNSS RTK device was 2.86 cm smaller than that of the reference method. When calculating the gross rutting, which consisted of the net rut depth and the bulge height, no statistically significant difference was found between the measurement methods used. Based on this result, the bulge height was also analyzed, and showed a statistically significant difference between the data recorded by the GNSS RTK device and other methods. It can be concluded that measuring the depth of ruts with a total station gives accurate data and represents the optimal modern field measurement method for the same or similar terrain conditions. In contrast, the GNSS RTK device, which constantly gives higher elevation points, can be used to measure gross rutting.
Croatian pedunculate oak (Quercus robur L.) populations represent southern range peripheral populations, often viewed as sources of valuable diversity and drought-resistant ecotypes. At the same ...time, they endure stronger selection pressures as a result of climate change. The leaves of 20 individuals per population (17) were sampled in a field trial and analyzed using 10 nuclear and 9 chloroplast SSRs to determine the level of intrapopulation genetic variability and genetic differentiation. Analysis with nSSRs revealed deviation from HWE in seven populations. AMOVA showed a high intra-population diversity (98.53%) and a small but statistically significant inter-population differentiation. Isolation by distance explained 19.6% of differentiation. Average FST between populations was low (0.013) compared with usual values for peripheral populations. Populations were rich in cpSSR haplotypes, confirming the hotspot of diversity caused by the encounter of recolonization routes. Unbiased haplotype diversity (HE) from 9 chloroplast SSRs and 325 individuals was (HE = 0.440). Sixty-six different haplotypes were grouped in three maternal lineages by both a median-joining network and a neighbor-joining algorithm. AMOVA for cpSSRs showed statistically significant diversity among populations (70.23%), suggesting genetic differentiation, but also a probable anthropogenic effect. AMOVA of nSSRs within and between lineages showed that original recolonization patterns of nuclear diversity were subsequently erased by gene flow.
Processing and characterization of PMMA-MXene composites were investigated. γ-Methacryloxypropyltrimethoxy (MEMO) silane was used to modify the surface of MXenes and improve the compatibility between ...MXenes and the polymer. The FTIR analysis revealed the formation of a chemical bond between MXene and MEMO silane, while the XPS analysis confirmed the presence of silicon in the functionalized MXene. PMMA composites with non-functionalized and functionalized MXene were prepared using a solution casting method. Tensile tests showed that, compared to neat PMMA, Young's modulus increased in both composites by 22.1 and 27.6%, respectively. As a result of coupling between the PMMA matrix and the surface-modified MXenes, the tensile strength also increased by about 37%. In addition, optical spectroscopy showed higher absorption for the composite with surface-modified MXenes and short-lived fluorescence with emission intensity sensitive to the crumpling of functionalized MXene nanosheets.
In this research, the influence of the thermal treatment of geopolymer gels at 300 °C, 600 °C and 900 °C when incorporated with 5% rare earth elements (REEs) in the form of (GP-Sm) Sm2O3 and (GP-Nd) ...Nd2O3 was investigated. Changes in the chemical and structural properties of the geopolymer gels during thermal treatment for 1 h were monitored. Physico-chemical characterization was performed using the following methods: diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), scanning electron microscopy with energy dispersive spectrometry (SEM-EDS), and X-ray photoelectron spectroscopy (XPS). Besides the characterization of the fundamental properties, some practical macroscopic properties were analyzed as well: sorptivity, open porosity, and Archimedean density. The stretching vibrations of Nd–O–Si and Sm–O–Si were confirmed at a value of around 680 cm−1and an Nd–O–Si absorption band at a higher value, together with the most dominant band of Si–O stretching vibration similar for all the samples. No significant chemical changes occurred. Structural analysis showed that for GP-Nd, the largest pore diameter was obtained at 900 °C, while for GP-Sm, the largest pore diameter was obtained at 600 °C. EDS confirmed the amount of dopant to be about 5%. X-ray photoelectron spectroscopy showed that for GP-Nd, the ratio of Si and Al changed the most, while for GP-Sm, the ratio of Si and Al decreased with increasing temperature. The contributions of both dopants in the GP-gel structure remained almost unchanged and stable at high temperatures. The atomic percentages obtained by XPS analysis were in accordance with the expected trend; the amount of Si increased with the temperature, while the amount of Al decreased with increasing temperature. The sorptivity and open porosity showed the highest values at 600 °C, while the density of both geopolymers decreased linearly with increasing temperature.
Every day, more people are becoming infected and dying from exposure to COVID-19. Some countries in Europe like Spain, France, the UK and Italy have suffered particularly badly from the virus. Others ...such as Germany appear to have coped extremely well. Both health professionals and the general public are keen to receive up-to-date information on the effects of the virus, as well as treatments that have proven to be effective. In cases where language is a barrier to access of pertinent information, machine translation (MT) may help people assimilate information published in different languages. Our MT systems trained on COVID-19 data are freely available for anyone to use to help translate information (such as promoting good practice for symptom identification, prevention, and treatment) published in German, French, Italian, Spanish into English, as well as the reverse direction.
Selenium (Se), an essential trace element for human and animal health, is covalently incorporated into amino acids, acts as a cofactor for antioxidant enzymes, and is involved in the maintenance of ...the immune system. The main goal of this investigation was to show the effect of Se supplementation, at levels slightly higher than the recommended values, combined with natural zeolite clinoptilolite on Se deposition in tissues (muscle and liver) and on the immune and antioxidative status of supplemented growing pigs. The experiment was carried out during a 98 d period on 60 pigs. Pigs were fed a standard feed mixture based on corn and soybean and were divided into four groups, according to the level of dietary selenium supplementation as follows: C-0.3 mg/kg DM organic Se, E1-0.5 mg/kg DM sodium selenite, E2-0.5 mg/kg DM organic selenium; E3-0.5 mg/kg DM organic Se+0.2% zeolite. Higher (
P
< 0.05) selenium concentrations were determined in the muscle and liver in growing pigs fed with higher organic Se in combination with zeolite compared to the lower organic Se concentration. Addition of organic Se increased (
P
< 0.05) Se deposition in muscle and liver compared to the equal amount of inorganic Se (E2 vs. E1). Higher organic Se in combination with natural zeolite addition increases (
P
< 0.05) proportion of pigs' cluster of differentiation (CD)45
+
compared to the same amount of inorganic Se and lower organic Se addition. The proportion of CD45
+
and CD4
+
lymphocytes was higher (
P
< 0.05) in E3 group compared to the other groups. Higher (
P
< 0.05) proportion of CD21
+
lymphocytes were measured in the E2 and E3 groups compared with the other groups. The highest (
P
< 0.01) activity of glutathione peroxidase (GSH-Px) in pig erythrocytes was observed in the E3 group, while higher (
P
< 0.05) activity of glutathione reductase (GR) was in all experimental groups related to the control one. A dietary addition of 0.5 mg/kg DM of organic Se in combination with zeolite (0.2% DM) has increased (
P
< 0.05) Se deposition in liver, muscle, and blood, compared to the dietary addition of 0.3 mg/kg DM of the organic Se.
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