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Vineyards are distinctive agroecosystems heavily influenced by local natural factors and traditional management practices, with significant implications for the quality and quantity of grape production. This study investigated the ecological impact of copper-containing fungicides on the accumulation and distribution of copper, manganese, chromium, and cobalt in the upper soil horizons of vineyards of varying ages in the Fruška Gora region, Serbia. The results indicated a marked difference in total copper content across vineyards, with the oldest vineyard exhibiting levels 6.9 times above the regulatory limit. Factor analysis delineated a strong correlation between copper accumulation and vineyard age while also highlighting the influence of landscape morphology on the spatial distribution of heavy metals. The findings suggest that copper accumulation is primarily related to agricultural practices, particularly the duration of fungicide application, while the distribution of other heavy metals is more closely associated with topographic features. The novelty of our research lies in the fact that we have shown that the assessment of copper accumulation in soil in vineyard ecosystems should take into account not only viticultural practices but also the history of land use and the landscape characteristics of the area. [ABSTRACT FROM AUTHOR]

Post-synthetic modification of proton-conducting metal–organic frameworks (MOFs) by loading small molecules capable of generating protons into pores is an efficient approach for developing a new type of material with improved ionic conductivity. Herein, the synthesis, characterization and proton conductivity of a novel electroneutral MOF based on palladium(II) meso-tetrakis(4-(phosphonatophenyl))porphyrinate, IPCE-1Pd, are reported. The exposure of the obtained framework to imidazole by the diffusion vapor method has surprisingly led to its complete crystal-to-crystal MOF-to-HOF transformation, resulting in the formation of a novel hydrogen-bonded organic framework (HOF) IPCE-1Pd_Im, which is the first example of such kind of structural change among all known MOFs. This modification has led to an almost 25-fold increase in the proton conductivity in comparison with the pristine MOF, reaching up to 6.54 × 10−3 S cm−1 at 85 °C and 95% relative humidity, which is one of the highest values among all known porphyrin-based HOFs. [ABSTRACT FROM AUTHOR]

A growing interest in dental practice in intranasal anesthesia using tetracaine and oxymetazoline dictates the need for their simultaneous determination in combination drugs and human saliva. Potentiometric multisensory systems based on perfluorosulfonic acid membranes, including polyaniline‐modified ones, were developed for these purposes. A change in the distribution of the sensor sensitivity to the related analytes was achieved by variation of the conditions for concentration polarization at the membrane interface with a studied solution due to a change in the intrapore volume, nature, and availability of the sorption centers, as well as the hydrophilicity of the membrane surface that were specified by the conditions for their synthesis and subsequent hydrothermal treatment. Reversibility of the analyte sorption using the chosen conditions for regeneration provided long‐term stable work of both the sensors and the calibration equations established by multivariate linear regression. The membrane modification promoted their resistance to fouling. The relative errors of the simultaneous tetracaine and oxymetazoline determination in the combination drug solutions were no greater than 7% and 11%, while in the artificial saliva solutions, they were 15% and 17%, respectively, when an array of the cross‐sensitive sensors based on the composite membranes prepared by different methods was used. The analysis errors were reduced to 3%–6% when analyzing the drug and to 0.2%–6% when analyzing the artificial saliva if an array was organized with the sensors based on the membrane with the dopant and the membrane without it, due to the decreasing correlation between their responses. Potentiometric multisensory systems based on perfluorosulfonic acid membranes, including polyaniline‐modified ones, were developed for the simultaneous determination of tetracaine and oxymetazoline in combination drugs and human saliva. Reversibility of the analyte sorption during regeneration provided long‐term stable work of the sensors and calibration equations established by multivariate linear regression. The analysis errors were 0.2%–6% for the sensor array based on the membrane with polyaniline and the one without it, due to the low correlation between the responses. [ABSTRACT FROM AUTHOR]

The cathode material of Na2/3Ni1/3Mn2/3O2 composition (NNMO) was obtained by the carbonate coprecipitation followed by solid-phase reaction and characterized by XRD analysis, ICP-MS, and electron and impedance spectroscopy. NNMO crystallizes in a P2-type layered hexagonal structure (sp. gr. P63/mmc), consists of spherical agglomerates of ~ 1–3 microns in size, and forms from the plate-like primary grains. The NNMO ionic conductivity value at room temperature was 1.8*10−4 and 1.3*10−4 S cm−1 when measured perpendicularly and parallel to the compression axis, respectively. The estimated in dc mode values of electronic conductivity were by 2–3 orders of magnitude less than ionic conductivity. The obtained materials were tested as cathodes in sodium-ion battery cells versus sodium metal. The discharge capacity of NNMO was 160 mAh g−1 and 86 mAh g−1 in the potential range of 1.5–4.0 V and 2.3–4.0 V, respectively (20 mA g−1). NNMO was shown to be stable under cycling in the potential range of 2.3–4.0 V. [ABSTRACT FROM AUTHOR]

We review applications of various nuclear resonance techniques for high-pressure experiments within the nearly 30-year-long operation of the Nuclear Resonance beamline at the European Synchrotron Radiation Facility (ESRF). Starting from a short introduction to the relevant techniques, we discuss the corresponding experimental setups, involved X-ray optics, and examples of applications. In addition, we emphasize the benefits of conducting high-pressure experiments in combination with other extreme conditions and introduce new focusing capabilities for extreme-pressure studies. Finally, we provide a short review of utilized detector systems, electronics, and available packages for data treatment. [ABSTRACT FROM AUTHOR]

Developing new materials for Li‐ion and Na‐ion batteries is a high priority in materials science. Such development always includes performance tests and scientific research. Synchrotron radiation techniques provide unique abilities to study batteries. Electrochemical cell design should be optimized for synchrotron studies without losing electrochemical performance. Such design should also be compatible with operando measurement, which is the most appropriate approach to study batteries and provides the most reliable results. The more experimental setups a cell can be adjusted for, the easier and faster the experiments are to carry out and the more reliable the results will be. This requires optimization of window materials and sizes, cell topology, pressure distribution on electrodes etc. to reach a higher efficiency of measurement without losing stability and reproducibility in electrochemical cycling. Here, we present a cell design optimized for nuclear resonance techniques, tested using nuclear forward scattering, synchrotron Mössbauer source and nuclear inelastic scattering. [ABSTRACT FROM AUTHOR]

The antioxidant properties of selenium nanoparticles coated with arabinogalactan have been studied. The nanoparticles were characterized by transmission electron microscopy and infrared spectroscopy. Arabinogalactan-coated selenium nanoparticles were incubated together with Ehrlich ascitic carcinoma cells and then exposed to microwave radiation. The antioxidant properties of selenium nanoparticles were evaluated using chemiluminescent analysis. The viability of Ehrlich ascitic carcinoma cells under microwave irradiation and incubation with selenium nanoparticles was assessed by flow cytometry. Under conditions of exposure to experimental tumor cells of microwave radiation, the concentration of free radicals in the cells did not change. The effect of arabinogalactan-coated selenium nanoparticles on tumor cells is expressed as an increase in the delay time for the activation of the antioxidant system. [ABSTRACT FROM AUTHOR]

Resonant absorption of a photon by bound electrons in a solid can promote an electron to another orbital state or transfer it to a neighboring atomic site. Such a transition in a magnetically ordered material could affect the magnetic order. While this process is an obvious road map for optical control of magnetization, experimental demonstration of such a process remains challenging. Exciting a significant fraction of magnetic ions requires a very intense incoming light beam, as orbital resonances are often weak compared to above‐band‐gap excitations. In the latter case, a sizeable reduction of the magnetization occurs as the absorbed energy increases the spin temperature, masking the non‐thermal optical effects. Here, using ultrafast X‐ray spectroscopy, this work is able to resolve changes in the magnetization state induced by resonant absorption of infrared photons in Co‐doped yttrium iron garnet, with negligible thermal effects. This work finds that the optical excitation of the Co ions affects the two distinct magnetic Fe sublattices differently, resulting in a transient non‐collinear magnetic state. The present results indicate that the all‐optical magnetization switching (AOS) most likely occurs due to the creation of a transient, non‐collinear magnetic state followed by coherent spin rotations of the Fe moments. [ABSTRACT FROM AUTHOR]

Phosphates Li1 +xTi1.8 –xFexGe0.2(PO4)3 (x = 0.1–0.3) with the NASICON structure have been prepared and studied for the first time. It has been shown that co-doping with germanium and iron leads to significant increase in the ionic conductivity of the prepared materials at low degrees of titanium substitution. The influence of the synthesis method (solid-state and sol-gel) and conditions of precursor processing on the ionic conductivity of the materials has been studied. Optimum conditions for the mechanical processing of precursors have been found to obtain ceramics with the highest conductivity. Li1.2Ti1.6Fe0.2Ge0.2(PO4)3 prepared by the solid-state method exhibits the highest ionic conductivity at room temperature (1.7 × 10–4 S/cm) among all samples. [ABSTRACT FROM AUTHOR]

Objectives Health care systems worldwide are facing a shortage in the pathology workforce that could negatively affect health care services, particularly oncology. To address this potential shortfall, the pathology community must identify the reasons why graduating students are not choosing pathology as a specialty. Methods We analyzed 226 free-text essay responses submitted by nonpathology residents at a teaching hospital. We used a general inductive approach and quantitative analysis to identify the barriers that prevent medical college graduates from choosing pathology as a specialty. Results Residents at our institution view pathology similar to residents from other countries, with the main obstacles to choosing pathology as a specialty being a perception that it lacks practical application to patient care or provides "no real help" and has a lack of patient interaction. In Russia specifically, there is a focus on the perceived negative aspects of autopsy as a barrier to selecting pathology. Less significant factors that may be based more on stereotypes than reality include the expectation that the work is not engaging, the emotional burden, and the occupational risks. Conclusions For medical students who place less importance on patient interaction, addressing these secondary factors could help select potential pathologists during students' undergraduate years. [ABSTRACT FROM AUTHOR]

The use of cation-exchange membranes as electrolytes for lithium metal batteries can prevent the formation of lithium dendrites during extended cycling and guarantee safe battery operation. In our study, the Nafion-212 membrane in lithium form solvated by a mixture of ethylene carbonate and propylene carbonate (EC-PC) was used as an electrolyte in a lithium metal battery with the LiFePO4 cathode. The Nafion-212-EC-PC electrolyte is electrochemically stable up to 6 V, indicating its suitability for high-energy density batteries. It has an ionic conductivity of 1.9 × 10−4 S/cm at 25 °C and a high lithium transference number. The symmetric Li|Nafion-212-EC-PC|Li cell shows a very low overvoltage of ~0.3 V at a current density of ±0.1 mA/cm2. At 25 °C, the LiFePO4|Nafion-212-EC-PC|Li battery exhibits a capacity of 141, 136, 125, and 100 mAh/g at 0.1, 0.2, 0.5, and 1C rates, respectively. It maintains a capacity of 120 mAh/g at 0 °C and 0.1C with stable performance for 50 charge/discharge cycles. The mechanism of conductivity and capacity retention at low temperatures is discussed. [ABSTRACT FROM AUTHOR]

Using LaBWO6 as a host, we have prepared a series of erbium-doped lanthanum borotungstates (LBTs), La1 – xErxBWO6, and Yb/Er-codoped La1 –x–yYbxEryBWO6, which crystallize in monoclinic crystal system (sp. gr. P21). The materials have been synthesized by ceramic route and a sol–gel (Pechini) process, followed by annealing. We have studied the spectral properties of the synthesized LBTs exhibiting the luminescence in the green spectral region upon the excitation in the near-infrared region. The highest efficiency, with Ben = 0.55%, has been obtained for La0.97Yb0.02Er0.01BWO6 composition. Sol–gel synthesis (Pechini process) has been shown to be the optimal approach for the preparation of such phosphors. Due to a combination of high upconversion efficiency and thermal stability, the synthesized upconversion phosphors can be used for the design of white light sources pumped in the near-IR spectral region. [ABSTRACT FROM AUTHOR]

The present study investigates the functionalecological status of typical light clay soils in vineyards in the southern region of Crimea, using both traditional (including fallow soils) and organic land-use systems. This analysis was carried out by examining agrochemical indicators, microbial respiratory activity, microbial biomass, and the ecological status of the microbial community. In organic vineyard soils, the mean substrate-induced respiration, microbial biomass carbon and the ratio of microbial biomass to organic carbon were found to be 2.8, 4.0, and 4.1 times higher, respectively, compared to conventional farm soils. On the contrary, the microbial metabolic coefficient was 1.4 times lower, signifying more favorable conditions for the functioning of the soil microbiota. The increased mobile sulfur content in organic vineyard soils (18.3 mg kg−1 vs. 8.0 mg kg−1 in traditional farms) and inadequate mobile phosphorus supply in some farms present potential risks. The suboptimal functional state of the microbiome in fallow soils previously under traditional plant protection necessitates comprehensive ecotoxicological analyses before development. Assessing the soil functional ecological status through an ecophysiological evaluation of the microbiome is vital for understanding ampelocenosis soils and making informed decisions on vineyard management practices. [ABSTRACT FROM AUTHOR]

All-solid-state lithium batteries are a promising alternative to commercially available lithium-ion batteries due to their ability to achieve high energy density, safety, and compactness. Electrolytes are key components of all-solid-state batteries, as they are crucial in determining the batteries' efficiency. Herein, the structure of LiM2(PO4)3 (M = Ti, Ge, Zr) and lithium-ion migration mechanisms are introduced as well as different synthetic routes and doping (co-doping), and their influence on conductivity is discussed. The effective methods of reducing electrolyte/electrode interface resistance and improving ion-conducting properties are summarized. In addition, different polymer/NASICON composites are considered. The challenges and prospects of practical applications of NASICON-type lithium phosphates as electrolytes for all-solid-state batteries are discussed. [ABSTRACT FROM AUTHOR]

The olefin separation from their mixture with paraffins by facilitated transport membranes is a very important process for the further macromolecular compounds production. Membranes loaded with silver ions, which are responsible for the facilitated olefin transport, are instable with time due to their reduction, while those containing protons catalyze the polymerization of olefins. In this work, membranes based on polyethylene with grafted sulfonated polystyrene in various ionic forms (H+, Li+, Na+) were used for the first time for the separation of the ethylene/ethane mixture. The influence of sulfonation time, relative humidity, and various ionic forms on ethylene separation was studied. The SEM study shows a non-uniform sulfur distribution over the membrane thickness for membranes sulfonated for different reaction times. With increasing sulfonation time and relative humidity the ethylene permeability and the factor of its separation with ethane increase. Separation factors for membranes in the Li+-form are shown to be as high as for membranes in the H+-form. A possible mechanism for the facilitated ethylene transport is discussed. [ABSTRACT FROM AUTHOR]

We have studied Cu–Zn and Cu–Ni containing catalysts on carbon supports based on IR-pyrolyzed chitosan and detonation nanodiamond (DND) and assessed their activity for the methanol steam reforming process. All of the catalysts have demonstrated rather high activity for this process and good stability over 30 h of continuous operation. The DND-based catalysts have been shown to have better performance, which seems to be due to their larger surface area and the nature of the functional groups on their surface. The activity of the bimetallic catalysts and the nature of the supports have been shown to be interrelated. [ABSTRACT FROM AUTHOR]

Hydrogen-bonded organic frameworks (HOFs) possessing high crystallinity, simple synthetic procedure and easy regeneration provide high efficiency as multifunctional systems, including applications as proton conductors. Porphyrinylphosphonates having acidic moieties, which can form multiple hydrogen bonds, together with tunable physical–chemical properties of a macrocycle may significantly improve the proton conductivity of such materials. Herein, the synthesis, characterization and proton-conducting properties of a novel anionic HOF based on a new complex of palladium(II) with meso-tetrakis(4-(phosphonatophenyl))porphyrin, HOF-IPCE-1Pd, are reported. Directed structural transformation of the framework by the exchange of dimethylammonium counterions for ammonium cations along with the absorption of ammonia and water molecules led to the formation of a more hydrolytically stable structure of HOF-IPCE-1Pd-NH3, demonstrating the proton conductivity of 1.27 × 10−3 S cm−1 at 85 °C and 85% RH, which is one of the highest among all known HOFs based on porphyrins. It is noteworthy that the reversible absorbance of water/ammonia molecules preserves the crystal structure of HOF-IPCE-1Pd-NH3. [ABSTRACT FROM AUTHOR]

The degradation of drugs is a substantial problem since it affects the safety and effectiveness of pharmaceutical products, as well as their influence on the environment. A novel system of three potentiometric cross-sensitive sensors (using the Donnan potential (DP) as an analytical signal) and a reference electrode was developed for the analysis of UV-degraded sulfacetamide drugs. The membranes for DP-sensors were prepared by a casting procedure from a dispersion of perfluorosulfonic acid (PFSA) polymer, containing carbon nanotubes (CNTs), whose surface was preliminarily modified with carboxyl, sulfonic acid, or (3-aminopropyl)trimethoxysilanol groups. A correlation between the sorption and transport properties of the hybrid membranes and cross-sensitivity of the DP-sensor to sulfacetamide, its degradation product, and inorganic ions was revealed. The analysis of the UV-degraded sulfacetamide drugs using the multisensory system based on hybrid membranes with optimized properties did not require a pre-separation of the components. The limits of detection of sulfacetamide, sulfanilamide, and sodium were 1.8 × 10−7, 5.8 × 10−7, and 1.8 × 10−7 M. The relative errors of the determination of the components of the UV-degraded sulfacetamide drugs were 2–3% (at 6–8% relative standard deviation). PFSA/CNT hybrid materials provided the stable work of the sensors for at least one year. [ABSTRACT FROM AUTHOR]

SYNCmoss is a software package dedicated to fitting Mössbauer spectra measured with a synchrotron Mössbauer source (SMS). Operation conditions of an SMS can be continuously varied from high resolution and low intensity to the opposite extreme. These variations influence the width and shape of the instrumental function. The main purpose of SYNCmoss is to fit data obtained with instrumental functions of various shapes. SYNCmoss allows the instrumental function to be extracted from the spectrum of a standard absorber, and then to utilize it in the fitting procedures for the samples studied. SYNCmoss is standalone software -- it does not require installations of any software environment. Setting input parameters and the fitting procedure are controlled within a graphical user interface. High-intensity mode of the SMS leads to a short acquisition time, allowing for fast (for example, operando) measurements resulting in a long sequence of spectra with close or smoothly varying parameters. For such cases, SYNCmoss provides an option to fit a series of spectra in automatic mode. SYNCmoss provides fitting models for various cases of hyperfine interaction including the full Hamiltonian for the combined interaction. Finally, for generality, the software has the ability to also fit conventional Mo¨ ssbauer spectra and simple cases of nuclear forward scattering spectra. [ABSTRACT FROM AUTHOR]

Casting compositions were developed for the first time based on phosphorus-containing polyol and hydroxyl-containing oligoethers in combination with melamine polyphosphate and copper orthohydrophosphate for the design of low-combustible foamed polyurethanes with an oxygen index of 32–36 vol %. It was found that, in the presence of CuHPO4⋅H2O, the smoke-developed index of developed FPUs under flame-combustion conditions decreased by 24% to 508 m2 kg–1. The obtained materials are characterized by a compressive strength of 120 kPa at 10% relative strain, which meets the requirements of GOST (State Standard) 56590–2015 and frost resistance up to 250 sequential freezing cycles. [ABSTRACT FROM AUTHOR]

Ion exchange membranes are widely used for water treatment and ion separation by electrodialysis. One of the ways to increase the efficiency of industrial membranes is their modification with various dopants. To improve the membrane permselectivity, a simple strategy of the membrane surface modification was proposed. Heterogeneous RALEX-CM membranes were surface-modified by ceria with a phosphate-functionalized surface. Despite a decrease in ionic conductivity of the prepared composite membranes, their cation transport numbers slightly increase. Moreover, the modified membranes show a threefold increase in Ca2+/Na+ permselectivity (from 2.1 to 6.1) at low current densities. [ABSTRACT FROM AUTHOR]

Ground penetrating radar is non-invasive technology suitable for mapping moisture content variations since it shows high sensitivity to changes in water saturation. In this work we used a GPR tomography approach to estimate moisture content within two small-leaved lime (Tilia cordata) and two Scots pine (Pinus sylvestris) trunks. Additional information was derived using the method of GPR zero-offset. GPR data was collected in Moscow (diurnal monitoring in September 2021) using a shielded GPR antenna working at 1500 MHz. Moisture values derived from GPR data were compared with the values obtained directly by measuring sampled wood cores gravimetrically. A good agreement was observed between GPR-derived moisture content and core sample-derived values. Notwithstanding GPR-derived moisture content is about two times higher than core sample-derived values, a strong linear relation with a determination coefficient more than 0.8 is observed. Diurnal monitoring did not reveal any significant changes in moisture content inside the trunks. It can be concluded that the period of early autumn in the Moscow region is characterized by a constant moisture content of the small-leaved lime trunk during the day. [ABSTRACT FROM AUTHOR]

Comparative results of studying the oxidative dehydrogenation of ethane (ODE) on catalytic vanadium-phosphorus oxide systems deposited by the molecular layering method on the surface of oxide supports (Al2O3, SiO2) have been presented. It has been found that the highest activity in ODE and selectivity for ethylene are exhibited by vanadium-phosphorus-containing catalysts. The influence of the acidity of catalytic systems on the activity and selectivity of the process has been revealed. The selectivity of the ODE process for ethylene reaches 90%. An increase in the oxygen concentration in the initial mixture from 3.5 to 20% leads mainly to a decrease in the selectivity of the ODE process with respect to the ethylene yield. [ABSTRACT FROM AUTHOR]

Replacing liquid electrolytes with solid-state conductors is one of the key challenges to increasing the safety and energy density of next-generation Li secondary batteries. In this work, the NASICON-type Li1+xAlxZryTi2−x−y(PO4)3 with 0 ≤ x, y ≤ 0.2 solid electrolytes were synthesized using solid-state and sol-gel techniques at various sintering temperatures (800, 900, and 1000 °C). Their morphology and conducting properties were studied to determine the optimal dopant content and synthesis method. Li1.2Al0.2Zr0.1Ti1.7(PO4)3 and Li1.1Al0.1Zr0.2Ti1.7(PO4)3 prepared at 900 °C using a solid-state reaction exhibit the highest total conductivity at 25 °C (7.9 × 10−4 and 5.4 × 10−4 S cm−1, respectively), which is due to the optimal size of lithium transport channels, as well as the high density of these samples. The potential profile of Li|Li1.2Al0.2Zr0.1Ti1.7(PO4)3|Li cells was retained during cycling at a current density of 0.05 mA cm−2 for 100 h, indicating a high interfacial Li metal/electrolyte stability. [ABSTRACT FROM AUTHOR]

Transitioning to energy-saving and renewable energy sources is impossible without accelerated development of hydrogen energy and hydrogen technologies. This review summarizes the state-of-the-art and recent advances of various hydrogen production processes, including but not limited to thermochemical and electrolytic processes. Their opportunities and limitations, operating conditions, and catalysts are discussed. Nowadays, most hydrogen is still produced by steam reforming of methane, its partial oxidation, or coal gasification. Considerable attention is also paid to natural gas pyrolysis. However, hydrogen produced using these technologies has a lot of impurities and needs additional purification. A series of technologies for hydrogen purification, including its filtration through palladium alloy membranes, and membrane catalysis, allowing hydrogen production and purification in one stage, are discussed. The main way to produce carbon-free hydrogen is water electrolysis using low-cost energy from nuclear or renewable sources. Both conventional and novel methods of hydrogen storage and transportation, which are an important part of the hydrogen economy, are reviewed. Biohydrogen production technologies are also discussed. Finally, prospects for further work in this field are provided. This review will be useful to researchers and manufacturers working in this field. [ABSTRACT FROM AUTHOR]

Perfluorosulfonic acid Nafion membranes are widely used as an electrolyte in electrolysis processes and in fuel cells. Changing the preparation and pretreatment conditions of Nafion membranes allows for the optimization of their properties. In this work, a Nafion-NMP membrane with a higher conductivity than the commercial Nafion® 212 membrane (11.5 and 8.7 mS∙cm−1 in contact with water at t = 30 °C) and a comparable hydrogen permeability was obtained by casting from a Nafion dispersion in N-methyl-2-pyrrolidone. Since the ion-exchange capacity and the water uptake of these membranes are similar, it can be assumed that the increase in conductivity is the result of optimizing the Nafion-NMP microstructure by improving the connectivity of the pores and channels system. This leads to a 27% increase in the capacity of the membrane electrode assembly with the Nafion-NMP membrane compared to the Nafion® 212 membrane. Thus, the method of obtaining a Nafion membrane has a great influence on its properties and performance of fuel cells based on them. [ABSTRACT FROM AUTHOR]

The effect of different nitrogen-doped carbon additives (carbon coating from polyaniline, N-doped carbon nanotubes, and N-doped carbon nanoparticles) on electrochemical performance of nanocomposites based on the olivine-type LiFePO4 was investigated. Prepared materials were characterized by XRD, SEM, TGA-MS, CHNS-analysis, IR-, Raman, and impedance spectroscopies. Polyaniline deposition on the LiFePO4 precursor with following annealing lead to the formation of a LiFePO4/C nanocomposite with a carbon coating doped with nitrogen. Due to nitrogen atoms presence in carbon coating, the LiFePO4/N-doped carbon nanocomposites showed enhanced conductivity and C-rate capability. The discharge capacities of the synthesized materials in LIBs were close to the theoretical value at 0.1 C and retained high values with increasing current density. At high C-rates, the best results were obtained for a more dispersed LiFePO4/C composite with carbon coating prepared from polyaniline previously in situ deposited on LiFePO4 precursor particles. Its discharge capacity reached 96, 84, 73, and 47 mAh g−1 at 5, 10, 20, and 60 C-rates, respectively. [ABSTRACT FROM AUTHOR]

Lithium metal batteries are one of the more promising replacements for lithium-ion batteries owing to their ability to reach high energy densities. The main problem limiting their commercial application is the formation of dendrites, which significantly reduces their durability and renders the batteries unsafe. In the present work, we used a single-ion conducting gel polymer electrolyte based on a poly(ethylene-ran-butylene)-block-polystyrene (SEBS) block copolymer, which was functionalized with benzenesulfonylimide anions and plasticized by a mixture of ethylene carbonate and dimethylacetamide (SSEBS-Ph-EC-DMA), with a solvent uptake of 160% (~12 solvent molecules per one functional group of the membrane). The SSEBS-Ph-EC-DMA electrolyte exhibits an ionic conductivity of 0.6 mSm∙cm−1 at 25 °C and appears to be a cationic conductor (TLi+ = 0.72). SSEBS-Ph-EC-DMA is electrochemically stable up to 4.1 V. Symmetrical Li|Li cells; further, with regard to SSEBS-Ph-EC-DMA membrane electrolytes, it showed a good performance (~0.10 V at first cycles and <0.23 V after 700 h of cycling at ±0.1 mA∙cm−2 and ±0.05 mAh∙cm−2). The LiFePO4|SSEBS-Ph-EC-DMA|Li battery showed discharge capacity values of 100 mAh∙g−1 and a 100% Coulomb efficiency, at a cycling rate of 0.1C. [ABSTRACT FROM AUTHOR]

The advent of X-ray free-electron lasers (XFELs) has revolutionized fundamental science, from atomic to condensed matter physics, from chemistry to biology, giving researchers access to X-rays with unprecedented brightness, coherence and pulse duration. All XFEL facilities built until recently provided X-ray pulses at a relatively low repetition rate, with limited data statistics. Here, results from the first megahertz-repetition-rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering (SCS) instrument of the European XFEL are presented. The experimental capabilities that the SCS instrument offers, resulting from the operation at megahertz repetition rates and the availability of the novel DSSC 2D imaging detector, are illustrated. Timeresolved magnetic X-ray scattering and holographic imaging experiments in solid state samples were chosen as representative, providing an ideal test-bed for operation at megahertz rates. Our results are relevant and applicable to any other non-destructive XFEL experiments in the soft X-ray range. [ABSTRACT FROM AUTHOR]

A synchrotron Mo? ssbauer source (SMS) enables conventional (energy-domain) Mo? ssbauer spectroscopy at synchrotron radiation facilities. In comparison with radioactive sources, SMS provides a beam of several micrometres in size, permitting studies of extremely small samples. The SMS linewidth can be narrowed at the expense of its intensity by varying the angular position and temperature of the key element of the SMS - an iron borate 57FeBO3 crystal. Here, in order to optimize the SMS performance, the angular and temperature dependencies of the SMS parameters have been studied and the optimal angular position and temperature of the crystal have been determined for highest intensity at specified source width. The results show that, when accepting broadening of the source width up to ~6 natural widths, the intensity of the SMS at the European Synchrotron reaches more than 105 γ-quanta s-1. In the opposite extreme, the width of the source approaches the natural width with intensity decreasing to about 103 γ-quanta s-1. These changes of intensity up to two orders of magnitude take place over a temperature range of about 0.5°C. For all temperature and angular conditions, the instrumental function of the source was derived; we also analyzed the modification of its shape when passing from the 'low-width' to 'high-intensity' extremes of SMS operation. Finally, we estimated the influence of the temperature instability and mosaicity of the iron borate crystal on the SMS performance. [ABSTRACT FROM AUTHOR]

Polymer electrolyte based on Nafion-117 membranes in the Li+ form with intercalated 1,3-dioxolane-dimethoxyethane solvent mixtures (DOL-DME) has been obtained. The obtained electrolyte Nafion-Li+-DOL-DME has been characterized by DSC analysis, IR- and impedance spectroscopy. The solvent uptake of membrane in the DOL-DME mixture amounts to 1.9. Nafion-Li+-DOL-DME is characterized by an ionic conductivity ~10−7 S cm−1 at room temperature. The comparative study of the electrochemical properties of Li–S batteries with liquid electrolyte (1M Li(CF3SO2)2N in DOL-DME) with polypropylene film (PP) or Nafion-Li+-DOL-DME and S/C composites with mesoporous carbon as cathode materials has shown that the use of membrane can improve cyclability of the cell. The first-cycle discharge capacities of S/C electrodes in the Li–S battery cells with PP and Nafion-Li+-DOL-DME were 730 and 450 mAh g−1, respectively (0.1 mV s−1). However, the discharge capacity of S/C in the cell with PP reduced significantly after 10 cycles. The Li–S battery with the use of membrane exhibits significantly enhanced cyclability. The discharge capacity of S/C in the cell with Nafion-Li+-DOL-DME amounts to 365 mAh g−1 after 10 cycles and to up to 290 mAh g−1 after 40 cycles. [ABSTRACT FROM AUTHOR]

The ideal and actual cycles of an aircraft gas-turbine engine (Brayton cycles) are analyzed. The basic measures increasing the actual effective work of the cycle and decreasing the fuel consumption are noted. The analysis shows that the overall efficiency of the cycle may be increased by employing the maximum possible gas temperature and large pressure rise. [ABSTRACT FROM AUTHOR]

This article presents the results of the development of membrane-catalytic methods for obtaining purified hydrogen of various degrees of purity required for feeding high-, medium-, and low-temperature fuel cells. In order to conduct this, porous ceramic catalytic converters were obtained using self-propagating high-temperature synthesis. These converters are suitable for high-speed processes for producing synthesis gas with different carbon monoxide content (0.08–0.1 vol. %), which can be used to feed fuel cells of various types. Using a hybrid catalytic membrane reactor, in which the stage of catalytic conversion of organic substrates was combined with the stage of selective extraction of ultrapure hydrogen (content of H2 was not less than 99.9999 vol. %) from the reaction zone, combined carbon dioxide and steam reforming of organic substrates of various origins were carried out. The result of the work was the creation of a prototype of a small-sized electric generator plant in which a catalytic membrane reactor was combined with a solid-oxide fuel cell. [ABSTRACT FROM AUTHOR]

Proton-exchange membranes based on gamma-irradiated films of PVDF and radiation-grafted sulfonated polystyrene with an ion-exchange capacity of 1.8 meq/g and crosslinking degrees of 0 and 3% were synthesized. A solvent-free, environmentally friendly method of styrene grafting from its aqueous emulsion, with a styrene content of only 5 vol.% was used. Energy dispersive X-ray mapping analysis showed that the grafted sulfonated polystyrene is uniformly distributed throughout the membrane thickness. The obtained materials had a proton conductivity up to 132 mS/cm at 80 °C and a hydrogen permeability of up to 5.2 cm2/s at 30 °C, which significantly exceeded similar values for Nafion®-212 membranes. The resulting membranes exhibited a H2/O2 fuel cell peak power density of up to 0.4 W/cm2 at 65 °C. Accelerated stability tests showed that adding a crosslinking agent could significantly increase the stability of the membranes in the fuel cells. The thermal properties and crystallinity of the membranes were investigated through differential scanning calorimetry and X-ray powder diffraction methods. The conductivity, water uptake, and mechanical properties of the membranes (stress–strain curves) were also characterized. [ABSTRACT FROM AUTHOR]

The influence of different conductive additives (carbon nanofibers (CNFs), carbon nanoplatelets, and pyrolytic carbon from sucrose (Sucr) or polyvinylidene fluoride) on the morphology, electron conductivity, and electrochemical performance of LiFePO4-based cathodes was investigated to develop the most efficient strategy for the fabrication of high-rate cathodes. Pyrolytic carbon effectively prevents the growth of LiFePO4 grains and provides contact between them, CNFs provide fast long-range conductive pathways, while carbon nanoplatelets can be embedded in carbon coatings as high-conductive "points" which enhance the rate capability and decrease the capacity fading of LFP. The LiFePO4/CSucr/CNF showed better performance than the other cathodes due to the synergy of the high-conductive CNF network (the electronic conductivity was 1.3 × 10−2 S/cm) and the shorter Li+ ion path (the lithium-ion diffusion coefficient was 2.1 × 10−11 cm2/s). It is shown that the formation of composites based on LFP and carbon nanomaterials via mortar grinding is a more promising strategy for electrode material manufacturing than ball milling. [ABSTRACT FROM AUTHOR]

The SASE3 soft X-ray beamline at the European XFEL has been designed and built to provide experiments with a pink or monochromatic beam in the photon energy range 250-3000 eV. Here, the focus is monochromatic operation of the SASE3 beamline, and the design and performance of the SASE3 grating monochromator are reported. The unique capability of a free-electron laser source to produce short femtosecond pulses of a high degree of coherence challenges the monochromator design by demanding control of both photon energy and temporal resolution. The aim to transport close to transform-limited pulses poses very high demands on the optics quality, in particular on the grating. The current realization of the SASE3 monochromator is discussed in comparison with optimal design performance. At present, the monochromator operates with two gratings: the low-resolution grating is optimized for timeresolved experiments and allows for moderate resolving power of about 2000-5000 along with pulse stretching of a few to a few tens of femtoseconds RMS, and the high-resolution grating reaches a resolving power of 10 000 at the cost of larger pulse stretching. [ABSTRACT FROM AUTHOR]

Lithium titanate composites with conducting additives are synthesized by the sol–gel method. As the conducting additives, carbon nanotubes (CNTs)—plain and heterosubstituted, graphene-like nanoflakes (CNFs), and the carbon coating formed by sucrose (S) pyrolysis are used. The introduction of carbon nanotubes considerably increases the reversible discharge capacity of composites including the case of high current densities. This occurs as a result of the formation of a three-dimensional network which sustains the fast transport of lithium ions and electrons between the particles of the anode material. Thus, at the current density of 200, 800, 1600, and 3200 mA/g, the reversible discharge capacity of the Li4Ti5O12/С/CNT is found to be 130, 107, 94, and 71 mA h/g, respectively. The use of CNFs as the conducting additive fails to considerably improve the properties of the anode material. [ABSTRACT FROM AUTHOR]