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We demonstrate a genuine method for three-dimensional pictorial reconstructions of two-dimensional, three-dimensional, and hybrid specimens based on confocal Raman data collected in a back-scattering geometry of a 532-nm setup. The protocol, or the titular PRISM (Phase-Resolved Imaging Spectroscopic Method), allows for sub-diffractive and material-resolved imaging of the object's constituent material phases. The spacial component comes through either the signal distal attenuation ratio (direct mode) or subtle light-matter interactions, including interference enhancement and light absorption (indirect mode). The phase component is brought about by scrutinizing only selected Raman-active modes. We illustrate the PRISM approach in common real-life examples, including photolithographically structured amorphous Al2O3, reactive-ion-etched homoepitaxial SiC, and Chemical Vapor Deposition graphene transferred from copper foil onto a Si substrate and AlGaN microcolumns. The method is implementable in widespread Raman apparatus and offers a leap in the quality of materials imaging. The lateral resolution of PRISM is stage-limited by step motors to 100 nm. At the same time, the vertical accuracy is estimated at a nanometer scale due to the sensitivity of one of the applied phenomena (interference enhancement) to the physical property of the material (layer thickness). [ABSTRACT FROM AUTHOR]

Potential energy surfaces of even–even superheavy nuclei are evaluated within the macroscopic-microscopic approximation. A very rapidly converging analytical Fourier-type shape parametrization is used to describe nuclear shapes throughout the periodic table, including those of fissioning nuclei. The Lublin Strasbourg Drop and another effective liquid-drop type mass formula are used to determine the macroscopic part of nuclear energy. The Yukawa-folded single-particle potential, the Strutinsky shell-correction method, and the BCS approximation for including pairing correlations are used to obtain microscopic energy corrections. The evaluated nuclear binding energies, fission-barrier heights, and Q α energies show a relatively good agreement with the experimental data. A simple one-dimensional WKB model à la Świa̧tecki is used to estimate spontaneous fission lifetimes, while α decay probabilities are obtained within a Gamow-type model. [ABSTRACT FROM AUTHOR]

The research hypothesis postulates that mycorrhizal fungal strains can increase the content of phosphorus (P) and selected micronutrients in tomato fruit. The aim of this study was to determine the suitability of three tomato cultivars for growing in a heated plastic tunnel, and to evaluate the influence of fungal strains applied to the rhizosphere of tomato plants on the concentrations of selected minerals, in particular P, iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn), in the fruit. A two-factorial experiment was conducted in 2015-2016. Tomatoes were grown in coco coir in a heated plastic tunnel in the Experimental Garden of the University of Warmia and Mazury in Olsztyn. The first experimental factor were three tomato cultivars, 'Growdena F1', 'Listell F1' and 'Torero F1', suitable for growing in a controlled environment. The second experimental factor was growing tomatoes in coco coir mats with and without fungal strains: control treatment (without fungal strains), growth medium inoculated with fungi of the genus Glomus, growth medium inoculated with a combination of fungi of the genus Trichoderma. The experiment had a s split-block design, with 10 plants per replicate in each treatment. In order to determine the mineral content of tomato fruit, plant material was dried at a temperature of 65°C and ground in an electric mill. The samples were analyzed in the Chemical and Agricultural Research Laboratory in Olsztyn to determine their content of P, Fe, Cu, Mn and Zn. The analyzed fungal strains did contribute to a significant increase in P concentrations in tomato fruit, compared with the control treatment. Fungi of the genera Glomus and Trichoderma ssp. increased the Fe content of tomato fruit by 12.5% and 16.9%, respectively, compared with the control treatment, and Glomus fungi increased also Mn concentration in tomato fruit. [ABSTRACT FROM AUTHOR]

Recent years have witnessed an increased interest in the cultivation and consumption of peppers. Therefore, new solutions are being sought to provide pepper plants with the most favorable conditions for growth and development. In view of the above, the aim of this study was to evaluate the effect of selected biostimulants on the biometric parameters, yield and nutritional value of Capsicum annuum fruit. The research hypothesis postulates that biostimulants can increase the yield and improve the nutritional quality of pepper fruit. The experiment was conducted in an unheated plastic tunnel. The experimental materials comprised three sweet ('Solario F1', 'Turbine F1' and 'Whitney F1') and two hot ('Cyklon' and 'Palivec') cultivars of C. annuum. It was found that the combined application of environmentally-friendly microbial-based biostimulants (BB Soil, BB Foliar, Multical, MK5 and Biocin F) did not clearly improve the morphological traits of pepper fruit, yield or the concentrations of sugars and organic acids in fruit, therefore their use is not economically justified. Hot peppers had a higher content of dry matter, total sugars and L-ascorbic acid than sweet peppers. The analyzed biostimulants increased nitrate (V) concentrations in the fruit of both hot and sweet peppers. 'Turbine F1' and 'Solario F1' were particularly prone to nitrate (V) accumulation in fruit, therefore the use of biostimulants should be limited in their cultivation. Pepper fruits with the largest horizontal diameter and the thickest skin should be preferred because these traits are associated with high sugar content. [ABSTRACT FROM AUTHOR]

In this report, we present transfer-free p-type hydrogen-intercalated quasi-free-standing epitaxial Chemical Vapor Deposition graphene on 15-mm × 15-mm semi-insulating vanadium-compensated on-axis 6H SiC(0001), characterized in that its room-temperature direct-current Hall-effect-derived hole mobility μ p = 5019 cm2/Vs, and its statistical number of layers (N), as indicated by the relative intensity of the SiC-related Raman-active longitudinal optical A 1 mode at 964 cm−1, equals N = 1.05. The distribution of the ellipsometric angle Ψ measured at an angle of incidence of 50 ° and λ = 490 nm points out to N = 0.97. The close-to-unity value of N implies that the material under study is a close-to-perfect quasi-free-standing monolayer, which is further confirmed by High-Resolution Transmission Electron Microscopy. Therefore, its spectroscopic properties, which include the Si H peak at 2131 cm−1, the histograms of Ψ and Δ , and the Raman G and 2D band positions, widths, and the 2D-to-G band intensity ratios, constitute a valuable reference for this class of materials. • Quasi-free-standing single-layer graphene in an industrial technology • Direct observation of the hydrogen-related Si-H peak at 2131 cm-1 • Parameters for effective ellipsometric characterization of QFS graphene on SiC • Referential database of graphene spectroscopic properties • Novel approach to graphene certification [Display omitted] [ABSTRACT FROM AUTHOR]

In this report, we demonstrate an applied protocol for layer-resolved Raman imaging and analysis of undesirable ad-layers found in Chemical Vapor Deposition graphene grown on copper foil and transferred onto an oxidized silicon substrate. The method assumes that the intensity of the silicon-related Raman-active mode at 520 cm-1 is attenuated by 2.3 % each time the light passes through a single graphene layer. Upon normalization with respect to a reference graphene-free area, the 520 cm-1 mode relative intensity r-I Si measured in a back-scatter mode follows a univalent function of the number of the graphene layers N. Since N is treated as a continuous argument, it can be ascribed a fractional value and considered statistically. Importantly, the r-I Si offers higher layer differentiation capability and unambiguity than non-functional indicators, including the 2D band width or the 2D-to-G band intensity ratio, thus providing unequivocal evaluation. [Display omitted] • Method for high-resolution Raman imaging of CVD graphene. • Truly functional and univalent protocol for layer-resolved analysis. • Applicable to multilayer graphene. • Useful extension for the Graphene Flagship technical standard. [ABSTRACT FROM AUTHOR]

A greenhouse experiment was conducted in 2011-12 to determine the effects of fertilization using an Asahi SL biostimulator on heavy metal concentrations in two cultivars of eggplants (Solanum melongena L.) grown in an unheated plastic tunnel in the garden of the Research and Experimental Station of the University of Warmia and Mazury in Olsztyn. Eggplants with their high nutritional and biological values plus popularity, eggplants are an important crop economically. However, due to their temperature requirements, eggplants are difficult to grow in regions with less favorable climatic conditions. Biostimulants and biopreparations are applied to protect plants against exogenous stressors, and to promote their healthy growth and development. Such protective treatments are increasingly applied in the cultivation of thermophilous vegetables in colder climates. The Asahi SL biostimulator supports the plant's natural defense mechanisms, thus alleviating the negative effects of adverse environmental conditions. Under optimal growing conditions the biostimulator helps crops reach their full genetic potential. The experimental materials comprised plants of two eggplant cultivars: Black Beauty and Violetta Lunga. Seedlings were grown in line with the generally observed standards for eggplant cultivation. The heavy metal content of plant material (in fruit) was determined. The concentrations of heavy metals and nitrates (V) in eggplants grown in an unheated plastic tunnel did not exceed the maximum permissible levels. The biostimulator exerted varied effects on the heavy metal and nitrate (V) contents of eggplants, and it increased the accumulation of mercury in the edible parts of eggplants. A significant increase in the concentrations of cadmium and nitrates (V) was noted in the cv. Black Beauty control eggplants. [ABSTRACT FROM AUTHOR]

In the framework of the macroscopic-microscopic approach the Yukawa folding procedure is used together with the Lublin-Strasbourg Drop liquid-drop type energy to describe atomic nuclei in the actinide region. The nuclear deformation is described by a 4-dimensional shape parametrisation similar to the well-known Funny-Hills expression. It is demonstrated that left-right asymmetry and non-axiality are present at the first and second saddle and should be included in the theoretical description. The importance of a different deformation of the proton and the neutron distribution also appears in the present analysis. [ABSTRACT FROM AUTHOR]

In the framework of the macroscopic-microscopic model fission barriers in the region of actinide nuclei are investigated. Taking left-right mass asymmetric and non-axial shapes into account is demonstrated to have a substantial effect on fission barrier heights. [ABSTRACT FROM AUTHOR]

The response of nuclear energy with respect the change of proton and neutron distributions is investigated. Contrary to most macroscopic-microscopic approaches, different radii and multipole deformations of both distributions are admitted here. The average part of the total energy is evaluated using the Yukawa-folded model, while the microscopic energy corrections are obtained within the Strutinsky and BCS methods. [ABSTRACT FROM AUTHOR]

Project financially supported by Minister of Education and Science in the range of the program entitled "Regional Initiative of Excellence" for the years 2019-2022, Project No. 010/RID/2018/19." now reads: "The results presented in this paper were obtained as part of a comprehensive study financed by the University of Warmia and Mazury in Olsztyn, Faculty of Agriculture and Forestry, Department of Agroecosystems and Horticulture, 30.610.016-110. "The results presented in this paper were obtained as part of a comprehensive study financed by the University of Warmia and Mazury in Olsztyn, Faculty of Agriculture and Forestry, Department of Agroecosystems and Horticulture, 30.610.016-110. [Extracted from the article]

In this report, we demonstrate a method for the enhancement of Raman active modes of hydrogen-intercalated quasi-free-standing epitaxial chemical vapor deposition graphene and the underlying semi-insulating 6H–SiC(0001) substrate through constructive signal interference within atomic-layer-deposited amorphous Al2O3 passivation. We find that an optimum Al2O3 thickness of 85 nm for the graphene 2D mode and one of 82 nm for the SiC longitudinal optical A1 mode at 964 cm–1 enable a 60% increase in their spectra intensities. We demonstrate the method's efficiency in Raman-based determination of the dielectric thickness and high-resolution topographic imaging of a graphene surface. [ABSTRACT FROM AUTHOR]

Kelvin Probe Force Microscopy is a method to assess the contact potential difference between a sample and the probe tip. It remains a relative tool unless a reference standard with a known work function is applied, typically bulk gold or cleaved highly oriented pyrolytic graphite. In this report, we suggest a verifiable, two-dimensional standard in the form of a photolithographically patterned, wire-bonded structure manufactured in the technology of transfer-free p-type hydrogen-intercalated quasi-free-standing epitaxial Chemical Vapor Deposition graphene on semi-insulating high-purity nominally on-axis 4H-SiC(0001). The particular structure has its hole density p S = 1.61 × 1013 cm−2 measured through a classical Hall effect, its number of the graphene layers N = 1.74 extracted from the distribution of the ellipsometric angle Ψ , measured at the angle of incidence AOI = 50 ° and the wavelength λ = 490 nm, and its work function ϕ G R = 4.79 eV postulated by a Density Functional Theory model for the specific p S and N. Following the algorithm, the contact potential difference between the structure and a silicon tip, verified at Δ V G R − Si = 0. 64 V , ought to be associated with ϕ G R = 4.79 eV and applied as a precise reference value to calculate the work function of an arbitrary material. [Display omitted] • QFS graphene on SiC as a KPFM reference standard. • Electrically verifiable and updatable. • A likely complement to HOPG and bulk gold. [ABSTRACT FROM AUTHOR]

The ability to precisely measure magnetic fields under extreme operating conditions is becoming increasingly important as a result of the advent of modern diagnostics for future magnetic-confinement fusion devices. These conditions are recognized as strong neutron radiation and high temperatures (up to 350 °C). We report on the first experimental comparison of the impact of neutron radiation on graphene and indium antimonide thin films. For this purpose, a 2D-material-based structure was fabricated in the form of hydrogen-intercalated quasi-free-standing graphene on semi-insulating high-purity on-axis 4H-SiC(0001), passivated with an Al2O3 layer. InSb-based thin films, donor doped to varying degrees, were deposited on a monocrystalline gallium arsenide or a polycrystalline ceramic substrate. The thin films were covered with a SiO2 insulating layer. All samples were exposed to a fast-neutron fluence of ≈ 7 × 10 17 cm−2. The results have shown that the graphene sheet is only moderately affected by neutron radiation compared to the InSb-based structures. The low structural damage allowed the graphene/SiC system to retain its electrical properties and excellent sensitivity to magnetic fields. However, InSb-based structures proved to have significantly more post-irradiation self-healing capabilities when subject to proper temperature treatment. This property has been tested depending on the doping level and type of the substrate. [ABSTRACT FROM AUTHOR]

In this paper, we report on the first experimental study on the impact of neutron radiation on quasi-free-standing (QFS) graphene. For this purpose, we have fabricated hydrogen-intercalated QFS graphene on semiinsulating high-purity 4H-SiC(0001), passivated it with an Al 2 O 3 layer, and exposed it to a fast-neutron fluence of ≈ 6. 6 × 1 0 17 cm−2. The results have shown that the graphene sheet is only moderately affected by the neutron radiation with the estimated defect density of ≈ 4 × 1 0 10 cm−2. The low structural damage allowed the Al 2 O 3 /graphene/SiC system to maintain its electrical properties and an excellent sensitivity to magnetic fields characteristic of QFS graphene. Consequently, our findings suggest that the system may be a promising platform for magnetic diagnostics in magnetic-confinement fusion reactors. However, the scope of its use should be a subject of further study. In this context, we have explored possible modes of damage and have concluded that the main factor that affects the electrical parameters of the structure is the impact of neutrons on the layer of hydrogen atoms saturating the SiC(0001) surface. We have shown, employing density functional theory (DFT) computations, that damage to the intercalating layer could lower hole concentration in graphene via reduced charge polarization and local coupling on the interface. [Display omitted] • Quasi-free-standing properties of graphene persist after neutron irradiation. • Post-radiation damage to the H intercalation lowers the carrier density in graphene. • A degree of self-healing in the system via surface diffusion of hydrogen. • Temperature above 200 °C facilitates the reconstruction of damaged H intercalation. [ABSTRACT FROM AUTHOR]

The technique of band-interaction calculations has been widely used for many years in the context of nuclear structure studies and a number of approximations have generally been made in this context. In this article we examine the impact of certain of these simplifications, basing our study on the interaction of some model bands. We show that large uncertainties can result when the interacting-band model is used under the assumptions that quite often are not even explicitly mentioned - neither verified. [ABSTRACT FROM AUTHOR]

The emission of light particles in coincidence with fast fission in near peripheral reactions of 40Ar+197Au at 30 MeV/u beam energy has been studied by using the Improved Quantum Molecular Dynamics Model (ImQMD). It is demonstrated that in the symmetrical fast fission of the heavy target-like fragment (TLF), the emission of the coalescence-invariant neutrons (CIN) is enhanced particularly at large angles in comparison to that in the events without fission. Due to the enhanced CIN emission and the accumulation of the isospin effect in the long-time process, the yield ratio of the CIN to the coalescence-invariant protons (CIP) in the fission events exhibits significant dependence on the symmetry energy E sym (ρ) varying with density. Considering that the large angle neutrons are experimentally advantageous to measure for the lower flying velocity and lower multiplicity, we emphasize that the yield ratio R CINP at large angles in the fast fission events can be used as a novel probe of the nuclear symmetry energy at sub-saturation densities. [ABSTRACT FROM AUTHOR]