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Titanium or niobium alloying is done in microalloyed steels to improve the mechanical properties by grain refinement. Contrary to niobium, titanium addition gives additional advantages of 1) lower rolling load in the mill and 2) low ferroalloy cost. However, recovery of titanium, owing to its high affinity toward oxygen, is highly inconsistent and depends mainly on secondary steelmaking process parameters like dissolved oxygen content in steel, chemical composition of slag, addition method of alloy, fluid flow conditions of the bath during and after the addition of alloy and temperature of steel. Herein, process data have been analyzed and correlated to the chemical composition of steel and slag to understand the influence of various process parameters on titanium yield. Industrial plant trials have been conducted with a modified ferrotitanium (FeTi) addition practice. FeTi wire injection is done in seven heats with different wire injection speed and bottom argon purging rate. It has been found that 200 m min−1 of injection speed along with differential flow rate of argon from porous plugs with 35 and 6 Nm3 h−1, respectively, yields better recovery of titanium. The titanium recovery increases by 4% compared to the earlier practice of wire injection and argon purging. [ABSTRACT FROM AUTHOR]

In current work, irradiation-induced microstructural evolution of the Cansas 3303 SiC fiber was investigated. This fiber was irradiated by 1.8 MeV argon ions at room temperature in the Shanghai Institute of Applied Physics, Chinese Academy of Sciences. The ion fluences were 5 × 1014, 1 × 1015, 2.5 × 1015 and 5 × 1015 ions/cm2 corresponding to the maximum doses of 0.27, 0.54, 1.35 and 2.70 displacements per atom (dpa), respectively. Irradiation effects were characterized by using micro-Raman spectroscopy and transmission electron microscopy. The results showed that the Cansas 3303 fiber consists of nanocrystalline SiC grains, carbon packets and carbon ribbons. Irradiation-induced amorphization accompanied with the decrease of SiC grain size was observed in the fiber with the increase of ion fluences. However, SiC grains still remained in this fiber up to the dose of 2.70 dpa. Besides, the reduction of the quantity and size in carbon packets and the annihilation of carbon ribbons in this fiber were also detected. [ABSTRACT FROM AUTHOR]

In this research work, we have synthesized non-crystalline Se85Te3Bi12 chalcogenide glasses by conventional melt quenching technique. The differential scanning calorimetry measurement of the synthesized specimen was done to confirm the glassy as well as non-crystalline nature of the bulk Se85Te3Bi12 alloy. The nano-thin films of thickness 30 nm of the synthesized sample at two different ambient argon pressures (1 Torr and 3 Torr) were made using the physical vapor condensation technique at a constant substrate temperature of 77 K using liquid nitrogen. The non-appearance of prominent peaks in the high-resolution x-ray diffractometer profile confirmed the non-crystalline nature of synthesized nano-thin films. The morphological analysis of the prepared nano-thin films using Field emission scanning electron microscopy confirmed the nanochalcogenide having particle size ranges from 30–90 nm. The Fourier transform infrared (FTIR) spectroscopy suggests the presence of moisture and carbon impurities in the prepared nano-thin films. The broad optical transmission shadow observed in the FTIR results is an essential requirement for new-generation IR systems. Based on UV-visible spectroscopy, optical parameters such as optical absorption coefficients, Urbach energy, optical band gaps, Tauc's parameter and extinction coefficients were measured for synthesized Se85Te3Bi12 nano-thin films. The value of absorption coefficients, Tauc's parameters, optical band gap and extinction coefficients increases with the increase of ambient argon pressure. The outcome of these studies recommends that these materials can be a preeminent candidate for photovoltaic applications. Photoluminescence spectroscopy results are accredited to the accumulation of non-crystalline nanochalcogenide particles on the substrates. DC conductivity measurements further confirm the semiconducting nature of the nanochalcogenide Se85Te3Bi12 thin films. [ABSTRACT FROM AUTHOR]

Products of thin-sheet copper are widely used in radio electronics, instrumentation, power engineering, etc. This article considers micro-plasma and TIG welding of copper with a thickness of 0.2 mm in argon and helium. As a result of the conducted research, it was established that in case of using helium as a shielding gas, the welding speed increases by more than 2 times compared to the microplasma process and by almost 5 times compared to TIG welding in argon. At the same time, the width of the weld and heat-affected zone (HAZ) decreases to 1.4…1.6 mm and 1.0…1.5 mm, respectively. Metallographic examinations of the welds did not reveal defects such as pores, cracks or lack of fusion. The weld microstructure consists of a set of equiaxed crystallites with a grain size of 4…8 μm without clearly expressed crystallization direction and with a smooth transition of the fusion line. The mechanical properties of the welded joints such as temporary resistance and microhardness were determined. Ref. 8, Fig. 7, Tab. 2 [ABSTRACT FROM AUTHOR]

Liquid argon technology is widely used by many previous and current neutrino experiments, and it is also promising for future large-scale neutrino experiments. When detecting neutrinos using liquid argon, many hadrons are involved, which can also interact with argon nuclei. In order to gain a better understanding of the detection processes, and to simulate neutrino events, knowledge of hadron-argon cross sections is needed. This paper describes a new procedure which improves upon the previous work with multi-dimensional unfolding to measure hadron-argon cross sections in a liquid argon time projection chamber. Through a simplified version of simulation, we demonstrate the validity of this procedure. [ABSTRACT FROM AUTHOR]

The study explores the specifications of a nanosecond overvoltage discharge in argon occurring between electrodes crafted from a superionic conductor, silver sulfide (Ag2S). The discharge was initiated under argon pressures ranging from 13.3 to 101 kPa, with a 2 mm separation between the polycrystalline Ag2S electrodes. Electrode material degradation within the discharge, alongside the introduction of Ag2S vapor into the interelectrode region, stemmed from microexplosions triggered by inherent surface irregularities on the electrodes. This discharge configuration holds potential as a plasma-chemical reactor for synthesizing thin films predicated on silver sulfide. Additionally, the study presents findings from analyzing Raman scattering spectra of laser radiation interacting with films synthesized from the Ag2S compound. [ABSTRACT FROM AUTHOR]

Sparging is a technique to remove an excess of dissolved oxygen from the wine with inerting gases before bottling to avoid negative consequences for its chemical and sensory properties. However, its effectiveness on these properties has not been studied in depth. This work investigates the effectiveness of different inerting gases (N2, CO2, and argon) in removing dissolved oxygen in different volumes of a model wine. The efficacy of these gases was also studied in white and red wine, as was their effect on the physicochemical characteristics. Sparging with N2 in the model wine gave the best results in terms of cost–benefits, and with CO2 the worst. The scaling in tanks of different sizes allowed us to establish that the N2 expenditure ranged between 0.09 L and 0.23 L of gas per liter of model wine, establishing an index (Lgas/Lwine) that can be very useful for wineries to remove the dissolved oxygen. Sparging treatments in white and red wine showed very similar results to the model wine. The effect on the chemical properties of the wines was, in some cases, different for white and red wine and for each gas used. The incorporation of oxygen and the subsequent sparging produced a significant loss of some volatile compounds of sensory interest and increased the content of others that have a negative sensory effect. In addition, it had a negative effect on the chromatic properties of red wines. [ABSTRACT FROM AUTHOR]

The crystal structure of anhydrous Al-MFI (NH4) containing adsorbed Ar has been determined and refined using synchrotron X-ray powder diffraction data taken at 90 K, and optimized using density functional theory techniques. Six highly occupied Ar sites almost completely fill the pore volume of the zeolite. Changing the gas flow from Ar to He at 90 K decreases the Ar occupancies of all six sites, but two decrease more than the others. Warming the sample from 90 to 295 K in Ar flow results in further decreases in site occupancies, but five of the original six sites persist. [ABSTRACT FROM AUTHOR]

There are few reported cases in which the spatial distribution of spectral emission coefficients of plasmas from tomographic optical emission spectroscopy measurements is analyzed based on a collisional-radiative model to diagnose the spatial distribution electron temperature of T e and density N e . This study aimed at in situ diagnosis of process plasma. The spectral radiance of 18 lines-of-sight was measured simultaneously in argon inductively coupled plasma. The spatial distribution of the excited level number density distribution was calculated from the spatial distribution of spectral emission coefficients obtained from spectral tomography calculations. The three-dimensional distribution of T e and N e was analyzed using a collisional-radiative model from the obtained spatial distribution of the excited levels number density. The effects of power and pressure on the dependence of the spatial distribution of T e and N e were discussed. Furthermore, data processing methods for spectral tomographic measurements with coarse wavelength resolution were also discussed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using high-speed shooting and shadow photography, the spatial structure of a pulsed discharge in a 1.5 mm long "pin(cathode)-plane" gap in nitrogen and argon in the pressure range from 0.25 to 2 atm was studied. It has been found that a spark discharge is realized in nitrogen and a diffuse form of discharge is realized in argon. For both cases, the presence of a microstructure of discharges in the studied pressure range was found, when the discharge is an aggregation of a large number of micron-diameter channels. It is shown that for each gas the dynamics of the discharge glow structure remains similar at different pressures. It has been established that the glow and microstructure of the discharge in nitrogen are similar to those in air. [ABSTRACT FROM AUTHOR]

The mechanochemical synthesis of titanium nitride during double mechanical activation of titanium powder is studied in argon and in nitrogen gas. The duration of mechanical activation of titanium in argon and nitrogen is varied in experiments. As suggested by the analysis of powder mixture morphology, X-ray diffraction analysis, and microanalysis, the preliminary mechanical activation of titanium in argon contributes to accelerating the mechanochemical synthesis of titanium nitride. Analytical relationships are obtained and theoretical estimates are given that make it possible to predict the process of double mechanical activation of titanium. [ABSTRACT FROM AUTHOR]

This paper studies supercritical argon adsorption in connected pores composed of cavity and neck by using a grand canonical Monte Carlo simulation. The effect of pressure, temperature, and cavity size were investigated systematically on the absolute and excess densities. Moreover, the sub-isotherm adsorption in the cavity and neck was also explored individually. We found that when the cavity is significantly larger than the neck, the total excess isotherm has three clear peaks, which are governed by the neck, cavity, and closed end. The first peak at low pressure is mainly caused by the adsorption in the pore neck, the second peak at higher pressure is largely in order to fill the cavity, and the third peak at higher pressure occurs because adsorbate molecules accumulate between previously adsorbed layers at the closed end. Thus, the peaks are found when the derivation of bulk density and absolute pore density in each section is almost equal. Furthermore, when the temperature is increased, the first and third peaks disappear slightly because the kinetic energy at high temperature reduces the fluid–solid and fluid–fluid interactions. Therefore, a plateau behavior in high-pressure isotherm can be observed because of the interplay between the effects of the closed end and high temperature in pore connectivity. The feature changes to a single peak prior to an increasing at high pressures when N2 adsorption is considered. Due to its molecular length is relatively large to the pore structures. This study offers the knowledge to understand and develop supercritical fluid in pore connectivity. [ABSTRACT FROM AUTHOR]

Positron scattering from the noble gas atoms neon and argon is calculated using the single-center convergent close-coupling (CCC) method. Unlike previous CCC calculations, we have relaxed the frozen-core approximation by fully opening the outermost s and p shells, and find better agreement with experiment for excitation energies and dipole polarizability. We have used this improved structure model to calculate elastic, elastic differential, total, momentum-transfer, electron-loss, and total bound excitation cross sections. We have applied a complex model potential calculation, scaled to our single-center CCC results, to obtain direct ionization and positronium-formation cross sections for these systems. This complex model potential was also used to calculate results between the positronium-formation and ionization thresholds, giving complete results from 10 - 5 eV to 5000 eV. Overall, good agreement is observed with past theory and experiment for most transitions. [ABSTRACT FROM AUTHOR]

The relativistic optical potential method has been used to calculate a complete set of cross sections for positron scattering from neon and argon in the energy range from zero to 1 keV. Elastic, positronium formation, excitation, direct ionization, and grand total cross sections are presented and compared to the recommended results of Ratnavelu et al. (J Phys Chem Ref Data 48:023102, 2019). Here, positronium formation is modeled as an ionization process by successively lowering the ionization thresholds. This process was carried out for the four lowest energy levels of positronium. [ABSTRACT FROM AUTHOR]

Abstract—The study of the effect of the initial conditions on the features of the formation and development of the anodic ionization wave between two electrodes with a tip–plane gap geometry in argon at atmospheric pressure is performed on the basis of a two-dimensional axisymmetric drift-diffusion model. [ABSTRACT FROM AUTHOR]

Accurate thermophysical properties will be essential to select and evaluate cryogenic fluids. The viscosity data of common cryogenic fluids was scattered below 200 K. To verify the data and reference correlations, in this work, the viscosity of nitrogen and argon in gas, liquid, and supercritical states were measured by using a vibrating-wire viscometer at temperatures between 90 K and 200 K and pressures between 0.3 MPa and 5 MPa. The standard uncertainty of the viscosity measurements was estimated to be 2.1 % over all temperature and pressure ranges. The results together with literature data were compared with the reference correlations. The results show good agreement between our measurements and those of the reference correlations within 2 %. [ABSTRACT FROM AUTHOR]

Featured Application: The research presented in this paper can be used to develop methods for determining optimal conditions for thermal and baric synthesis of materials. By the method of molecular dynamics, computer simulation of the processes of isobaric cooling of argon particle systems under initial conditions with a temperature of 150 K at pressure values from 0.1 to 4 MPa to a temperature of 40 K with cooling rates of 108, 109, 1010, 1011 and 1012 K/s was performed. As a result of a computer experiment, coordinate arrays of particles were obtained, which were subjected to the procedure of three-dimensional Voronoi partitioning to identify and calculate the number of elementary cells of the crystal structure. Analysis of the structure of argon solid phases formed during isobaric cooling allowed us to deduce an estimated pattern between the concentration of FCC (face-centered cubic) cells in solid argon and the cooling rate from the liquid state. The evaluation of the orientation of the axes of translation of crystal cells in the array of particle coordinates made it possible to classify the solid phases formed as a result of cooling as single crystals, glassy media with the inclusion of clusters and single cells of FCC structures. It was revealed that during isobaric cooling at a rate not exceeding 108 K/s, argon completely crystallizes, at isobaric cooling rates of 109–1010 K/s, the union of elementary cells of the crystal structure into clusters is observed in glassy argon, and at rates of 1011 K/s and higher at pressures of 1 MPa and lower, solid vitreous phases of argon are formed in which no crystal structure cells are detected. [ABSTRACT FROM AUTHOR]

This work reveals the synergistic effect of argon/nitrogen double plasma alteration on the mechanical properties of para‐aramid fiber/epoxy resin composites with various laminating sequences. Acoustic emission monitored interface failure during tensile, bending and fracture testing. A comparative analysis was conducted on the bending performance of the composites modified by argon/nitrogen double plasma and single plasma. The results showed that the synergistic effect of nitrogen and high‐energy molecule argon optimized the modifying effect of argon/nitrogen double plasma. The optimal modification parameters obtained through fiber extraction testing analysis are power 200 W, time 120 s, and Ar/N2 double gas flow rate of 12 sccm. After plasma treatment, twill weave modifies better than plain weave. The AE signal amplitude of PX1 is minimized during stretching. Due to the difference in internal bending stiffness of PX2, interface delamination failure is more likely to occur. The PX5 had greater fiber and matrix debonding failure between mode‐II fracture tests due to the weak modification effect of plain weave and its difficulty in deformation. In ballistic testing, PX1 blocks impact force through fiber bundle stretching deformation, while PX4 is more brittle. Highlights: Prepare para‐aramid/epoxy resin composites with various laminating sequences.Study on the interfacial properties of composites treated with double plasma.The composites with different gas sources treatment were analyzed.Acoustic emission analysis was used to identify interface failure modes.The bonding strength between plain and plain interfaces is the lowest. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the antimicrobial effect of cold atmospheric plasma (CAP) on pathogens associated with canine bacterial keratitis. Materials and methods: Pseudomonas aeruginosa, Staphylococcus pseudintermedius, and Streptococcus canis strains, which were obtained from dogs with infectious keratitis, were subjected to testing. For each species, four isolates and a reference strain were cultivated on Columbia sheep blood agar and treated with the kiNPen Vet® plasma pen from Neoplas GmbH, Greifswald, Germany. Various continuous treatment durations (0.5, 2, and 5 min) were applied, along with a 0.5-min treatment repeated four times at short intervals. These treatments were conducted at distances of 3 and 18 mm between the agar surface and the pen. Results: CAP treatment reduced bacterial growth in all three species. The most effective treatment duration was 5 min at 3 mm distance, resulting in inhibition zones ranging from 19 to 22 mm for P. aeruginosa, 26-45 mm for S. pseudintermedius and an overall reduction of bacterial growth for Str. canis. Inhibition zones were smaller with decreasing treatment duration and larger distance. Treatment times of 30 s repeated four times and 2 min showed comparable results. Treatment with argon alone did not lead to visible reduction of bacterial growth. Conclusion: Argon cold atmospheric plasma demonstrated a potent in vitro antimicrobial effect on P. aeruginosa, S. pseudintermedius and Str. canis strains with the latter showing the highest sensitivity. [ABSTRACT FROM AUTHOR]

Crustal deformation is characterized by brittle and ductile faults that accommodate at different scales the strain imposed by plate tectonics. The aim of this contribution is to show with the help of different examples how the in situ 40Ar/39Ar dating of synkinematic neocrystallized minerals in ductile shear zones and the step-heating 40Ar/39Ar dating of synkinematic authigenic clays in fault gouges can bring information on the timing of fault activity. However, due to their complex evolution, interpretation of the argon signature in fault zones requires consideration of several effects among which re- or neocrystallization, inheritance and fluid interaction processes are dominant. [ABSTRACT FROM AUTHOR]

Ammonia is an efficient hydrogen energy carrier and a potential zero-carbon fuel for internal combustion engines. However, the poor ignition and combustion performances of ammonia limit its further application in homogeneous charge compression ignition engines. This study proposes to employ an inert gas argon as a diluent to improve ammonia's ignition and combustion performances. Furthermore, the effect of adding hydrogen is also investigated under a wide calculation range of compression ratio, excess oxygen ratio, and argon ratio through thermodynamic analysis. The calculation results indicate that replacing nitrogen with argon can significantly shorten the ignition delay time and promote the thermal conversion efficiency and power density. Under a specific condition (compression ratio = 19 and excess oxygen ratio = 3.0), when replacing air with an argon-oxygen mixture of argon/oxygen ratio = 79: 21, the ignition delay time of pure ammonia reduces from 700 ms to 0.31 ms, the thermal conversion efficiency increases from 65.1% to 78.2%, and the power density raises by approximately 20%. Nevertheless, the NO volume fraction grows by 1179 × 10−6 VOL due to the high temperature. The ignition delay time drops with the increase of hydrogen blend ratio. With an initial condition of 1250 K and 3.0 MPa, the ignition delay time decreases by 81%–95% when the hydrogen blend ratio is elevated from 5% to 20%. However, adding hydrogen also falls the thermal conversion efficiency and elevates the NO volume fraction. A hydrogen blend ratio of 5% is an excellent tradeoff value. • Ignition and thermal efficiency of HCCI ammonia engines is improved by argon. • Thermal efficiency close to 80% in the HCCI ammonia engines is indicated. • Characteristics of combustion and emissions of HCCI ammonite engines are analyzed. • A hydrogen of 5% VOL is a favorable tradeoff for HCCI ammonia engines using argon. [ABSTRACT FROM AUTHOR]

A method of producing nitrogen-alloyed steel is considered. The nitrogen alloying technologies based on the use of nitrided ferromanganese and nitrogen purge gas are analyzed and compared to choose the most effective one for the TAGMET conditions. To produce SA 20A steel with a regulated nitrogen content (100–300 ppm), it is proposed to purge metal with nitrogen and argon during treatment in a ladle furnace and during and after degassing. Proprietary software controlling the purging of steel with nitrogen and argon from the control panel of the ladle furnace and the vacuum degassing unit has been developed. This ensured effective control of the nitriding process and achievement of the required nitrogen content in steel. Changing over from alloying with nitrided ferromanganese to purging with nitrogen gas made it possible to eliminate the pyroelectric effect and to reduce the secondary oxidation and contamination of steel with non-metallic inclusions. [ABSTRACT FROM AUTHOR]

The impact of argon and helium purging flow rates of 4 1/min and 10 1/min on fusion zone dimensions and shape was investigated. Experiments were performed during an autogenous stationary TIG welding process for welding times of 7 s, 14 s, and 21s. For a welding time of 7 s, the flow rate of the argon and helium purging gases almost did not affect the fusion zone. When the welding time was extended (14 s), the argon purging flow rate also had no significant effect on the fusion zone. However, increasing the helium purging flow rate resulted in a significant (approx. 20 %) increase in weld penetration. Arc time of 21 s and an argon flow rate of 10 l/min decreased the weld penetration by around 17 %. On the other hand, an increased helium flow rate had the opposite effect, leading to an increase of approx. 17 % in weld penetration. [ABSTRACT FROM AUTHOR]

Neutrinos were produced immediately after Big-bang. These are the most abundant particles after photons. Neutrinos are literally jam packing the Universe and are associated with some of the deepest mysteries of nature. These are excellent carriers of information from the past of Universe through sources like bursting stars and black holes which we do not have a direct access to. Consequently, there has been a surge in the study of neutrinos and their interaction with matter. However, since neutrinos are very weakly interacting particles, these have feeble cross-sections. Nonetheless, cross-section measurement is the basic ingredient for any higher order neutrino studies. Therefore, in this work we report the cross-section measurements of neutrino interactions with three atmospheric gases viz; Oxygen, Water and Argon. This study is done using NuWro event generator. Nuwro is a Polish code developed by some eminent researchers at Wroclaw University of Poland. It is configured using well known physical models of neutrino interaction. The cross-section measurements are taken in an energy interval of hundreds of MeV to a few GeV,which is also best suited to study neutrino oscillations. We also try a novel way to define the scattering potential for neutrino interactions as a function of initial neutrino flux. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Developing antibacterial materials is an efficient way to reduce the risk of harmful microorganism to human body. As a kind of popular textiles, cotton fabric (CF) is easy to breed microorganism and it is necessary to render it with biocidal effect. In this work, a water-soluble N-halamine precursor, (E)-1-(4-(allyloxy)phenyl)-N-(2-(piperazin-1-yl)ethyl)methanimine (APPEM), was synthesized and grafted onto cotton fabric through an argon plasma-induced grafting polymerization process. Afterward, the grafted cotton fabric was exposed to dilute sodium hypochlorite solution to change N–H bond into N–Cl bond and then the antibacterial cotton fabric (CF-APPEM-Cl) was obtained. The treated cotton fabric presented considerable biocidal efficacy and stability against UV light, washing, and storage. Escherichia coli (6.63 logs) and Staphylococcus aureus (6.44 logs) could be effectively inactivated within 60 min. Also, the oxidative chlorine on the fabric recovered over 76.9 and 81.5% after UV irradiation for 24 h and 50 washing cycles, respectively. And the oxidative chlorine remained 85% after 30 days of storage. Meanwhile, the mechanical properties of cotton fabric were hardly affected by this antibacterial treatment. This work provides a simple and efficient way to prepare antibacterial cotton fabric with high performance, which might be helpful to promote the development of antibacterial textiles. [ABSTRACT FROM AUTHOR]

The thermodynamic properties of the CaO-Al2O3-VOx slag system are of great significance to the direct alloying of vanadium in the smelting process of vanadium steel. In this paper, the phase equilibrium relationship of the CaO-Al2O3-VOx system under argon atmosphere at 1500 °C was studied with a high-temperature phase equilibrium experiment. Combined with SEM-EDS, XRD, and XPS, the types and compositions of each phase of the equilibrium slag samples and the content of different valence states of the vanadium element were determined. The result shows that under argon atmosphere (p(O2) = 10−3 atm) at 1500 °C, the CaO-Al2O3-VOx slag system contains four three-phase regions, seven two-phase regions, and a single-phase region (glass phase). The phase equilibrium results were plotted in a CaO-Al2O3-V2O5-VO2 spatial phase diagram, and the phase equilibrium results were projected on the CaO-Al2O3-V2O5 and CaO-Al2O3-VO2 pseudo-ternary phase diagrams, respectively. In the end, the rationality of projecting the phase equilibrium results to the pseudo-ternary phase diagram was quantitatively evaluated. [ABSTRACT FROM AUTHOR]

Ischemic stroke (IS), primarily caused by cerebrovascular obstruction, results in severe neurological deficits and has emerged as a leading cause of death and disability worldwide. Recently, there has been increasing exploration of the neuroprotective properties of the inert gas argon. Argon has exhibited impressive neuroprotection in many in vivo and ex vivo experiments without signs of adverse effects, coupled with the advantages of being inexpensive and easily available. However, the efficient administration strategy and underlying mechanisms of neuroprotection by argon in IS are still unclear. This review summarizes current research on the neuroprotective effects of argon in IS with the goal to provide effective guidance for argon application and to elucidate the potential mechanisms of argon neuroprotection. Early and appropriate argon administration at as high a concentration as possible offers favorable neuroprotection in IS. Argon inhalation has been shown to provide some long-term protection benefits. Argon provides the anti-oxidative stress, anti-inflammatory and anti-apoptotic cytoprotective effects mainly around Toll-like receptor 2/4 (TLR2/4), mediated by extracellular signal-regulated kinase 1/2 (ERK1/2), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), nuclear factor kappa-B (NF-ĸB) and B-cell leukemia/lymphoma 2 (Bcl-2). Therefore, argon holds significant promise as a novel clinical neuroprotective gas agent for ischemic stroke after further researches to identify the optimal application strategy and elucidate the underlying mechanism.

Summary: Background: Argon (Ar) has been proposed as a potential therapeutic agent in multiple clinical conditions, specifically in organ protection. However, conflicting data on pre-clinical models, together with a great variability in Ar administration protocols and outcome assessments, have been reported. The aim of this study was to review evidence on treatment with Ar, with an extensive investigation on its neuroprotective effect, and to summarise all tested administration protocols. Methods: Using the PubMed database, all existing pre-clinical and clinical studies on the treatment with Ar were systematically reviewed (registration: https://doi.org/10.17605/OSF.IO/7983D). Study titles and abstracts were screened, extracting data from relevant studies post full-text review. Exclusion criteria included absence of full text and non-English language. Furthermore, meta-analysis was also performed to assess Ar potential as neuroprotectant agent in different clinical conditions: cardiac arrest, traumatic brain injury, ischemic stroke, perinatal hypoxic-ischemic encephalopathy, subarachnoid haemorrhage. Standardised mean differences for neurological, cognitive and locomotor, histological, and physiological measures were evaluated, through appropriate tests, clinical, and laboratory variables. In vivo studies were evaluated for risk of bias using the Systematic Review Center for Laboratory Animal Experimentation tool, while in vitro studies underwent assessment with a tool developed by the Office of Health Assessment and Translation. Findings: The systematic review detected 60 experimental studies (16 in vitro, 7 ex vivo, 31 in vivo, 6 with both in vitro and in vivo) investigating the role of Ar. Only one clinical study was found. Data from six in vitro and nineteen in vivo studies were included in the meta-analyses. In pre-clinical models, Ar administration resulted in improved neurological, cognitive and locomotor, and histological outcomes without any change in physiological parameters (i.e., absence of adverse events). Interpretation: This systematic review and meta-analysis based on experimental studies supports the neuroprotective effect of Ar, thus providing a rationale for potential translation of Ar treatment in humans. Despite adherence to established guidelines and methodologies, limitations in data availability prevented further analyses to investigate potential sources of heterogeneity due to study design. Funding: This study was funded in part by Italian Ministry of Health-Current research IRCCS and by Ministero della Salute Italiano, Ricerca Finalizzata, project no. RF 2019-12371416.

We report the laser intensity dependence of multiply charged atomic ions (MCAIs) Arn+ with 2 ≤ n ≤ 8 from argon clusters in focused nanosecond laser fields at 532 nm. The laser field, in the range of 1011–1012 W/cm2, is insufficient for optical field ionization but is adequate for multiphoton ionization. The MCAI sections of the mass spectra for clusters containing 3700 and 26 000 atoms are dominated by Arn+ with 7 ≤ n ≤ 9, extending to Ar14+. While the distributions of the MCAIs remain largely constant throughout the intensity range of the laser, the abundance of Ar+ relative to the abundances of the MCAIs increases dramatically with increasing laser intensity. Consequently, exponential fittings of the yields result in a larger exponent for Ar+ than for MCAIs, and the exponents of MCAIs with 2 ≤ n ≤ 8 are similar, with only slight variations for different charge states. The width of the arrival time and, hence, the corresponding kinetic energy of Ar+ also increases with increasing laser intensities, while the width of the arrival time of MCAIs remains constant throughout the range of measurements. These results call for more detailed theoretical investigations in this regime of laser–matter interactions. [ABSTRACT FROM AUTHOR]

The protonated HCl dimer and trimer complexes were prepared by pulsed discharges in supersonic expansions of helium or argon doped with HCl and hydrogen. The ions were mass selected in a reflectron time-of-flight spectrometer and investigated with photodissociation spectroscopy in the IR and near-IR regions. Anharmonic vibrational frequencies were computed with VPT2 at the MP2/cc-pVTZ level of theory. The Cl–H stretching fundamentals and overtones were measured in addition to stretch–torsion combinations. VPT2 theory at this level confirms the proton-bound structure of the dimer complex and provides a reasonably good description of the anharmonic vibrations in this system. The trimer has a HCl–HClH+–ClH structure in which a central chloronium ion is solvated by two HCl molecules via hydrogen bonding. VPT2 reproduces anharmonic frequencies for this system, including several combinations involving core ion Cl–H stretches, but fails to describe the relative band intensities. [ABSTRACT FROM AUTHOR]

An alternative material has been proposed as an absorber for a mask blank for lithography in the vicinity of a wavelength of 11.2 nm – Ni. It has been established in this work that the optimal angle for efficient sputtering of Ru, Be, and Ni targets by accelerated argon ion sources for fabrication of a Ru/Be multilayer structure with an upper Ni layer is an angle of 60° degrees. At this angle, the etching rate for all three materials is 35 ± 5 nm/min at an argon ion energy of 800 eV and an ion current density of 0.5 mA/cm2. [ABSTRACT FROM AUTHOR]

Weld surfacing is the process of applying a layer of metal to the surface of metal objects by simultaneously melting the substrate. As a result of this process, the metal content of the padding weld can be as high as several tens of percents. It is a method used to regenerate machine parts and improve the properties of the surface layer, increasing its resistance to abrasion, corrosion, erosion, and cavitation. It also supports the repair and creation of permanent protective coatings in the engineering, automotive, energy, and aerospace industries. This makes it possible to repair damaged parts instead of completely replacing them, saving time and production costs. Plasma surfacing technology is used for components that require high hardness and corrosion resistance under various environmental conditions. Plasma wire surfacing is not sufficiently presented and described in the current literature, which creates problems in determining the appropriate process parameters. The influence of variable plasma surfacing parameters on steel C45 significantly affects surfacing weld geometry, the dilution factor, and microhardness. Higher currents can increase the dilution factor, integrating more base metal into the weld pool, which may alter the chemical composition and mechanical properties of the weld. Variations in surfacing speed and heat input also affect the microhardness of the surfaced joint, with higher heat inputs potentially leading to softer welds due to slower cooling rates. Optimizing these parameters is essential to achieving desired surfacing weld characteristics and ensuring the structural integrity of C45 steel joints. This paper presents the influence of varying plasma surfacing parameters on the surfacing geometry, the dilution factor, and microhardness. The tests were carried out on a Panasonic TM-1400 GIII automated surfacing machine with CastoMag 45554S solid wire as the filler material. Flat bars of C45 steel were prepared, and then the variable parameters of the surfacing process were developed. Tests were carried out to determine the dilution factor, followed by microhardness measurements. The results showed a significant dependence of the effect of the parameters on the surfacing geometry and the dilution factor.

A new method of efficiently transforming water vapor into hydrogen was investigated by dielectric barrier discharge (DBD) loaded with bamboo carbon bed structured by fibrous material in an argon medium. Hydrogen productivity was measured in three different reactors: a non-loaded DBD (N-DBD), a bamboo carbon (BC) bed DBD (BC-DBD), and a quartz wool (QW)-loaded BC DBD (QC-DBD). The effects of the quality ratio of BC to QW and relative humidity on hydrogen productivity were also investigated in QC-DBD at various flow rates. The reaction process and mechanism were analyzed by scanning electron microscopy, X-ray photoelectron spectroscopy, N2 physisorption experiments, infrared spectroscopy, and optical emission spectroscopy. A new reaction pathway was developed by loading BC into the fibrous structured material to activate the reaction molecules and capture the O-containing groups in the DBD reactor. A hydrogen productivity of 17.3 g/kWh was achieved at an applied voltage of 5 kV, flow rate of 4 L/min, and 100% relative humidity (RH) in the QC-DBD with a quality ratio of BC to QW of 3.0.

Photodissociation of the van der Waals complex Ar–I2 after excitation into the Rydberg states of I2 has been investigated with velocity map imaging of photofragments. Formation of the translationally hot ions of argon Ar+ with three modes in kinetic energy distribution has been revealed. The measured dependence of the kinetic energy of Ar+ on the pumping photon energy indicates the appearance of Ar+ from three channels of the photodissociation of the linear intermediate Ar+–I–I− containing chemically bound argon. These channels are (1) dissociation into Ar++ I2−; (2) three-body dissociation into (Ar+)* + I* + I−, with (Ar+)* and I* being the 2P1/2 states of the species; and (3) two-body electron photodetachment, giving rise to Ar+ + I2 + e. Three indicated channels are similar to those established for the photodissociation of trihalide anions. This similarity confirms the conclusion on the formation of the Ar+–I–I− intermediate, which is isoelectronic to the trihalide anion Cl–I–I−. The mechanism of the Ar+–I–I− formation involves two-photon excitation of the complex Ar–I2 into the Rydberg state of I2 converted into the ion-pair state and further electron transfer from Ar to I+ of the ion-pair state. The self-assembling of the structure making the formation of the Ar+–I–I− intermediate energetically accessible is confirmed by modeling the dynamics in the excited linear complex Ar–I2. Photoexcitation of the van der Waals complexes of noble gases with halogens into the ion-pair states of halogen is supposed to be a promising approach for generating the new chemical compounds of noble gas atoms. [ABSTRACT FROM AUTHOR]

Photodissociation of the van der Waals complex Ar–I2 after excitation into the Rydberg states of I2 has been investigated with velocity map imaging of photofragments. Formation of the translationally hot ions of argon Ar+ with three modes in kinetic energy distribution has been revealed. The measured dependence of the kinetic energy of Ar+ on the pumping photon energy indicates the appearance of Ar+ from three channels of the photodissociation of the linear intermediate Ar+–I–I− containing chemically bound argon. These channels are (1) dissociation into Ar++ I2−; (2) three-body dissociation into (Ar+)* + I* + I−, with (Ar+)* and I* being the 2P1/2 states of the species; and (3) two-body electron photodetachment, giving rise to Ar+ + I2 + e. Three indicated channels are similar to those established for the photodissociation of trihalide anions. This similarity confirms the conclusion on the formation of the Ar+–I–I− intermediate, which is isoelectronic to the trihalide anion Cl–I–I−. The mechanism of the Ar+–I–I− formation involves two-photon excitation of the complex Ar–I2 into the Rydberg state of I2 converted into the ion-pair state and further electron transfer from Ar to I+ of the ion-pair state. The self-assembling of the structure making the formation of the Ar+–I–I− intermediate energetically accessible is confirmed by modeling the dynamics in the excited linear complex Ar–I2. Photoexcitation of the van der Waals complexes of noble gases with halogens into the ion-pair states of halogen is supposed to be a promising approach for generating the new chemical compounds of noble gas atoms. [ABSTRACT FROM AUTHOR]

The article reports the excitation of a helical argon atmospheric pressure plasma jet using a pulse-modulated 13.56 MHz radio frequency (RF) power source. This helical structure is observed in open ambient air, which is far different from the conventional conical shape. This helical structure originates due to the periodic pressure variation in the discharge region caused by pulse-modulated RF (2 kHz modulation frequency) and propagates downstream into the ambient air. The geometrical characteristics of the observed structure are explored using optical imaging. Moreover, the influence of various input parameters, viz., duty cycle, gas flow rate, and RF power, of the modulated pulse on the formation of a helical structure are studied. These helical structures have an implication on the plasma jet chemical features (enhancement of reactive oxygen and nitrogen species) as these are involved in an increase in air entrainment into the ionization region desired for various plasma applications. [ABSTRACT FROM AUTHOR]

Ion beam processes related to focused ion beam milling, surface patterning, and secondary ion mass spectrometry require precision and control. Quality and cleanliness of the sample are also crucial factors. Furthermore, several domains of nanotechnology and industry use nanoscaled samples that need to be controlled to an extreme level of precision. To reduce the irradiation-induced damage and to limit the interactions of the ions with the sample, low-energy ion beams are used because of their low implantation depths. Yet, low-energy ion beams come with a variety of challenges. When such low energies are used, the residual gas molecules in the instrument chamber can adsorb on the sample surface and impact the ion beam processes. In this paper we pursue an investigation on the effects of the most common contaminant, water, sputtered by ultralow-energy ion beams, ranging from 50 to 500 eV and covering the full range of incidence angles, using molecular dynamics simulations with the ReaxFF potential. We show that the expected sputtering yield trends are maintained down to the lowest sputtering yields. A region of interest with low damage is obtained for incidence angles around 60° to 75°. We also demonstrate that higher energies induce a larger removal of the water contaminant and, at the same time, induce an increased amorphization, which leads to a trade-off between sample cleanliness and damage.

The features of argon radiation mixed with molecular and atomic additives in condensing supersonic jets are analyzed. Mixtures of argon (95%) with methane (5%) and argon (95%) with monosilane (5%) are used. The mixture's particles are activated by a well-focused electron beam. The dependence of the radiation intensity of individual argon lines on the gas-dynamic parameters in the jet is studied. In a certain pressure range, different various compositions of mixtures, not only anomalously intense emission was recorded on individual spectral lines of argon (ArI) in mixtures with methane and monosilane, but also the role of clusters of a certain size and composition was revealed. At the same time, a similar effect is not detected in the spectrum of argon (ArII) ions. It is established that the cause of the anomaly is a highly efficient molecular cluster mechanism of the selective excitation of the individual levels of argon atoms, which is absent in noncondensing jets and weakens at the stage of the formation of large clusters. The main channels of energy transmission are reviewed and discussed. Based on the data obtained, an empirical model of the excitation-emission process is proposed. [ABSTRACT FROM AUTHOR]

Using argon as an actinometric atom requires knowledge of its electron excitation kinetics. In turn, this kinetics is largely determined by electron impact excitation cross-sections as well as quenching rate constants for the argon metastable levels. Unfortunately, the published experimental data for these cross-sections differ both in their magnitude and in the type of energy dependence. We have shown that if we exclude the first point from the 2004 data sets, then the cross sections normalized at the 20 eV point can be fairly well approximated by well-known fitting formulas. [ABSTRACT FROM AUTHOR]

Argon metastable levels quenching rate constant data are collected and analyzed from about 30 experimental studies. The main attention is paid to molecules that are used in plasma-chemical processes in microelectronics. All data are presented in detailed tables. They correspond to room temperature. The results obtained can be useful in developing models of the actinometric method for diagnosing low-temperature low-pressure plasma, as well as models of low-pressure discharges in argon-containing mixtures. [ABSTRACT FROM AUTHOR]

The results of experimental data and evaluation of the influence of the plasma gas composition on the properties of wear-resistant coatings deposited by various gas-thermal methods are presented. It is shown that, for the majority of existing types of wear-resistant coatings used in various branches of production, plasma sputtering of coatings using argon and nitrogen as the plasma-forming gas may replace the application of wear-resistant coatings using compressed air as the plasma-forming gas. At the same time, the use of a mixture of compressed air and hot hydrocarbons from the exhaust gases of a diesel internal combustion engine of a car as a plasma-forming gas during air-plasma sputtering should be carefully substantiated. [ABSTRACT FROM AUTHOR]