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As a threat to meeting the global demand for food created by the continued growth of population, different methods are being applied to enhance seed germination and plant growth. This study investigates the effect of hydrogen-rich water (HRW) and different plasma-activated waters (PAW) and their combinations including HRW, PAW1, PAW2, HPAW1, and HPAW2 on the seed germination of lentils. Different arc discharge reactors are generated under atmospheric pressure in the air. Optical emission spectroscopy was used to detect the radiative species formed in the plasma zone. Raman spectra and physicochemical properties of different waters were investigated. The results demonstrated significant differences in the properties of different activated waters compared to control water. On day 3 after treatment, the fraction and length of germinated seeds were evaluated. During germination, treated water significantly increased germination parameters such as final germination percentage, mean germination time, germination index, and coefficient of germination velocity. HPAW2 exhibited the highest germination index (GI), which combines germination percentage and speed. The plasma systems also effectively reduced the pH of PAW1 and PAW2, with a greater decrease observed in HPAW1 and HPAW1. Analysis of nitrite and nitrate levels revealed that HPAW2 had the highest concentrations, indicating more reactive processes in the presence of hydrogen. Based on our results, it can be concluded that lentil seed germination can be increased using PAW and hydrogenated PAW combined. [ABSTRACT FROM AUTHOR]

This study explores the effects of chamber pressure on the electrical and thermodynamic characteristics of a low-pressure thermal plasma jet. The investigation focuses on current–voltage characteristics, arc voltage fluctuations, plasma jet temperature, electron density, and velocity within the range of 100–500 A arc current, at chamber pressures of 100 Pa, 1 kPa, and 3 kPa. Spectral analysis of the arc voltage reveals the presence of distinct frequencies, including restrike, Helmholtz, and acoustic modes, which exhibit varying behavior under different chamber pressure conditions. Restrike frequency shows an increase with decreasing chamber pressure, while Helmholtz frequency remains unaffected, and the power density of the acoustic frequency diminishes, eventually disappearing from the spectrum. The transition of the plasma jet from a continuum regime to a frozen state with decreasing chamber pressure is observed along with its shock structures. Optical emission spectroscopy is utilized to map the excitation temperature and electron density profile along the jet axis, demonstrating that the jet temperature and density peaks at the compression zone. Furthermore, Mach probe measurements of the plasma jet velocity at different axial locations, under various chamber pressure conditions, illustrate that the plasma jet maintains a supersonic state, regardless of chamber pressure. However, after the formation of a Mach disk, the jet velocity becomes subsonic. The highest velocity is achieved at 100 Pa chamber pressure, reaching Mach 2.9 at 50 mm from the anode exit. This research enhances our understanding of thermal plasma jets under low-pressure conditions, contributing to the advancement of knowledge in their applications across various domains. [ABSTRACT FROM AUTHOR]

This Perspective paper deals with an overview of particle-in-cell/Monte Carlo collision models applied to different plasma-propulsion configurations and scenarios, from electrostatic (E × B and pulsed arc) devices to electromagnetic (RF inductive, helicon, electron cyclotron resonance) thrusters, as well as plasma plumes and their interaction with the satellite. The most important items related to the modeling of plasma–wall interaction are also presented. Finally, the paper reports new progress in the particle-in-cell computational methodology, in particular, regarding accelerating computational techniques for multi-dimensional simulations and plasma chemistry Monte Carlo modules for molecular and alternative propellants. [ABSTRACT FROM AUTHOR]

For plasma window (PW) applications, we developed the cascade arc discharge device with an indirectly heated hollow cathode. The 8-mm channel diameter hollow cathode made of a lanthanum hexaboride (LaB 6) was heated by the C/C composite heater surrounding the cathode to increase the thermionic electron emission. The PW developed successfully separated 2.4 kPa and 16 Pa, and the pressure separation capability was sustained for over 1 h. H- β Stark broadening measurement and the Thomson scattering measurement showed that the electron density and temperature inside the channel reached 10 19 – 10 20 m − 3 and 2.0 eV, respectively. The power balance analysis on the electron thermal energy revealed that the neutral density and temperature inside the channel were as high as 10 23 m − 3 and 4000 K, respectively. The relation between the pressure separation capability and the neutral temperature showed that the flow inside the channel of the PW had the molecular flow feature. The SEM-EDX analysis on the LaB 6 cathode showed that boron diffused to the molybdenum (Mo) shaft during plasma operation, which supported the LaB 6 cathode. Mo shaft became brittle after more than 50 h of operation, exhibiting the necessity of buffer material between the LaB 6 cathode and Mo shaft for long-duration operation. [ABSTRACT FROM AUTHOR]

The present research deals with the production and characterization of geopolymers prepared by mixing metakaolin with sodium silicate, sodium hydroxide solution and different amounts of electric arc furnace dust derived from the production of carbon steel, to be used by the construction industry. Specimens with compositions containing 90, 80, 70, 60 and 50 g of metakaolin and respectively 10, 20, 30, 40 and 50g of electric arc furnace dust powder were prepared. A blank composition containing metakaolin, sodium silicate, sodium hydroxide solution and free from electric arc furnace dust were also prepared for comparison. After production and hardening, all samples were characterized regarding compressive strength and water absorption. Hardened samples with compositions containing 10 and 30g of electric arc furnace dust were then submitted to a release test in order to evaluate the heavy metals elution. It has been observed that the addition of electric arc furnace dust worsens the pastes workability during their production in this way limiting the amount of electric arc furnace dust which may be added to the geopolymeric matrix. However, samples containing 90 g of metakaolin and 10 g of electric arc furnace dust still maintain fair compressive strength (about 27 MPa), low water absorption (about 28 %) and display limited elution of heavy metals. An additional thermal treatment of 1h at 700 °C, performed to induce sintering of the geopolymeric composites and therefore to reduce their porosity, did not lead to materials with improved performances. [ABSTRACT FROM AUTHOR]

We report a low cost, simple method to fabricate reduced graphene oxide (rGO) optical sensors from recycled batteries. The rGO nanosheets were exfoliated by electrochemical method under the assistant of electric arc using 5 % KOH or NaOH electrolytes. The rGO nanosheets show interlayer distances ranging from 3.98 to 6.22 Å, and thicknesses from 0.62 to 6.00 nm, corresponding from 1 to 10 layers, respectively, determined from X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM) measurements. Selected area electron diffraction (SAED) measurement indicates that rGO nanosheets content Miller-Bravais indices of (1–210) and (0–110) planes, and the hexagonal diffraction pattern of (0–110) plane of graphene sheets with d-spacing of 2.13 Å. Low defect densities in exfoliated rGO nanosheets were confirmed by I D /I G ratios ∼0.16 to 0.18 via Raman. The rGO nanosheets exfoliated in NaOH electrolyte have 19.35 % lower oxygen content compared to those exfoliated in KOH electrolyte inspected from XPS spectra. The performance of the rGO optical sensors is controlled by defects created from oxygen functional groups formed during exfoliation process. The responsivity and response (rise) time of NaOH-exfoliated rGO sensor are 0.46 A/W and 2.3 s, respectively. These values are 21 % (for responsivity) larger and 35 % (for rise time) smaller than those of KOH-exfoliated rGO sensor. The best-in-class of high gain were demonstrated in this study for the rGO optical sensors prepared from disposed graphite rods. The results demonstrate how disposed batteries can be recycled to produce photodetectors and other optoelectronic devices using cheap and relatively nontoxic methods. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2)-based steel making is expected to become a major driver of intercontinental low-carbon H 2 imports. Eight H 2 supply scenarios based on either local H 2 production at major steel producing locations (Germany/Japan), or liquid H 2 carrier (dibenzyltoluene/perhydrodibenzyltiluene, DBT/PDBT) import from the United Arab Emirates, and their integration with H 2 direct reduced iron (H-DRI) and electric arc furnace (EAF) processes, are investigated using process modeling. Solar energy-based PDBT import using surplus heat for dehydrogenation is the most cost-competitive H 2 import scenario in Germany's case (levelized steel production cost, ∼685 $/tLS, with carbon emissions, ∼237 kgCO 2 /tLS). In Japan's case this scenario is the most economically favorable of all scenarios (∼736 $/tLS), with emissions (∼350 kgCO 2 /tLS) comparable to natural gas-DRI-EAF with 50% carbon capture. Steam methane reforming with carbon capture-based PDBT import is neither environmentally nor economically viable. PDBT-based H-DRI-EAF production cost is sensitive to electricity, H 2 production, dehydrogenation energy, and carbon costs. • LOHC import from UAE to Germany/Japan for steel making is expected to be feasible. • Integrated LOHC dehydrogenation and HDRI-EAF steel making processes are proposed. • Renewable LOHC steel making emissions are 75% lower than for conventional DRI-EAF. • Renewable LOHC steel can be produced within medium-bound projected H-DRI-EAF cost. • SMR-CCS LOHC is neither environmentally nor economically competitive. [ABSTRACT FROM AUTHOR]

With recent trends moving towards sustainable approaches in adherence to environmental, social, and governance (ESG) standards, research is actively focused on sustainable production of high-potential materials. In this study, a successful synthesis pathway was demonstrated for a graphene/tungsten carbide (WC) nanocomposite via pulsed arc discharge in liquid medium, utilizing crude palm oil and commercial cooking palm oil as liquid precursors. The synthesis of the graphene/WC nanocomposites was carried out by applying current with amplitude of 80 A and 100 A to the tungsten electrode immersed in the liquid palm oil, subjected to 150 arc discharges. A comparative investigation was performed to examine the morphological and functional characteristics of the materials synthesized from the different types of palm oil under different current conditions. In addition, the synthesized nanocomposites were assessed with respect to their gas sensing performance. Impressively, the CRG100(150) nanocomposite (produced from crude palm oil with current of 100 A) exhibited gas sensing response of 4.853% upon injection of 200 ppm of ethanol. The CRG100(150) nanocomposite also demonstrated short response and recovery time of 43 s and 182 s, respectively. Thus, the successful synthesis of CRG100(150), utilizing a natural precursor via arc discharge in liquid, paves the way for the development of sustainable gas sensing materials. [ABSTRACT FROM AUTHOR]

The disposal of electric arc furnace (EAF) slag is often problematic, with most of it ending up being landfilled rather than recycled. Incorporating EAF slag into the typical clay-feldspar-quartz system to produce useful ceramics offers a potential and environmentally safer option. Thermodynamics package FactSage 8.2 was employed to predict the equilibrium-products of sintering process of EAF slag mixtures at different temperatures ranging from 600 to 1600 °C. Subsequent ceramic products were fabricated at a temperature of 1150 °C following the thermodynamic analysis by considering the fraction of liquid formation and the viscosity of the system. These products were further subjected to X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses and compared to the thermodynamic predictions. The physical performance of the products was also examined by evaluating the shrinkage, water absorption, apparent porosity, bulk density and modulus of rupture (MOR). When EAF slag was added to the base mixture, there was a positive trend of improvement in the physical properties and specifically, MOR peak value of 37.56 MPa was obtained when 40 % EAF slag was added. However, the MOR value as well as other physical properties started to decline when the base mixture had more than 40 % EAF slag. Conclusively, incorporating 40 % EAF slag improved the final product and correlated with the thermodynamic studies, process parameters, and experimental assessments of the ceramic tiles. [ABSTRACT FROM AUTHOR]

Electrical and fast imaging measurements are performed on an experimental device designed to study the dynamics of electric arcs in the DC regime. The work presented here investigates the relationship between electrical fluctuations and material ejection from the electrode surface. Cross-analysis of the electrical and imaging data reveals a significant correlation between electrical fluctuations in the kHz range and particle emission from the electrode surface. Different types of ejection are presented and a study of the dynamics of the ejected particles is carried out through the analysis of a statistically significant number of trajectories. [ABSTRACT FROM AUTHOR]

This article presents the author's methodology for testing selected parameters of a low-current vacuum arc, implemented using an innovative test stand based on a vacuum discharge chamber with a contact system mounted inside. In order to verify the validity of the adopted research methodology, as well as the correctness of the operation of the developed laboratory bench, measurements and calculations were made, among other things, of the energy and burning time of the vacuum arc, depending on selected factors, such as pressure and the delay time of the contact opening, calculated from the "passage through zero" of the sinusoid of the current flowing through the system. The tests were performed at 230 V and a current of 5 A for two pressure values: p1 = 1.00 × 105 Pa (atmospheric pressure) and p2 = 4.00 × 10−3 Pa (high vacuum environment). It was found that the vacuum insulation technique allows a significant reduction in the value of the arc energy and the burning time of the arc. It was also observed that in the case of a high vacuum environment, the ignition of the vacuum arc occurs after a time equal to about 3 ms from the "passage through zero" of the current flowing through the system. Below this value, the phenomenon did not occur. The results obtained provide an opportunity for the design and manufacturing of vacuum switchgear, where there is the prospect of reducing the negative effects associated with the arc burning process in the contact gap. [ABSTRACT FROM AUTHOR]

The development of multi‐principal‐element alloys (MPEAs) with unique characteristics such as high work hardening capacity similar to well‐known alloy systems like Hadfield steel X120Mn12 (ASTM A128) is a promising approach. Hence, by exploiting the core effects of MPEAs, the application range of conventional alloy systems can be extended. In the present study, work‐hardening MPEAs based on the equimolar composition CoFeNi are developed. Mn and C are alloyed in the same ratio as for X120Mn12. The production route consists of cast manufacturing by an electric arc furnace and surface functionalization via mechanical finishing using ultrasonic‐assisted milling (USAM) to initiate work hardening. The microstructure evolution, the hardness as well as the resulting oscillating wear resistance are detected. A pronounced lattice strain and grain refinement due to the plastic deformation during the USAM is recorded for the MPEA CoFeNi‐Mn12C1.2. Consequently, hardness increases by ≈380 HV0.025 in combination with a higher oscillating wear resistance compared to the X120Mn12. This shows the promising approach for developing work‐hardening alloys based on novel alloy concepts such as MPEAs. [ABSTRACT FROM AUTHOR]

Background: Silver nanoparticles are extensively researched for their antimicrobial properties. Cold atmospheric plasma, containing reactive oxygen and nitrogen species, is increasingly used for disinfecting microbes, wound healing, and cancer treatment. Therefore, this study examined the effect of water activated by dielectric barrier discharge (DBD) plasma and gliding arc discharge plasma on the antimicrobial activity of silver nanoparticles from Alborzia kermanshahica. Methods: Silver nanoparticles were synthesized using the boiling method, as well as biomass from Alborzia kermanshahica extract grown in water activated by DBD and GA plasma. The physicochemical properties of the synthesized nanoparticles were evaluated using UV-vis spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta potential analysis, transmission electron microscopy (TEM), and gas chromatography-mass spectrometry (GC-MS) analysis. Additionally, the disk diffusion method was used to assess the antimicrobial efficacy of the manufactured nanoparticles against both Gram-positive and Gram-negative bacteria. Results: The spectroscopy results verified the presence of silver nanoparticles, indicating their biosynthesis. The highest amount of absorption (1.049) belonged to the nanoparticles synthesized by boiling under GA plasma conditions. Comparing the FTIR spectra of the plasma-treated samples with DBD and GA revealed that the DBD-treated samples had more intense peaks, indicating that the DBD method proved to be more effective in enhancing the functional groups on the silver nanoparticles. The DLS results revealed that the boiling method synthesized silver nanoparticles under DBD plasma treatment had a smaller particle size (149.89 nm) with a PDI of 0.251 compared to the GA method, and the DBD method produced nanoparticles with a higher zeta potential (27.7 mV) than the GA method, indicating greater stability of the biosynthesized nanoparticles. Moreover, the highest antimicrobial properties against E. coli (14.333 ± 0.47 mm) were found in the DBD-treated nanoparticles. TEM tests confirmed that spherical nanoparticles attacked the E. coli bacterial membrane, causing cell membrane destruction and cell death. The GC-MS results showed that compounds like 2-methylfuran, 3-methylbutanal, 2-methylbutanal, 3-hydroxy-2-butanone, benzaldehyde, 2-phenylethanol, and 3-octen-2-ol were much higher in the samples that were treated with DBD compared to the samples that were treated with GA plasma. Conclusion: The research indicated that DBD plasma was more efficient than GA plasma in boosting the antimicrobial characteristics of nanoparticles. These results might be a cornerstone for future advancements in utilizing cold plasma to create nanoparticles with enhanced antimicrobial properties. [ABSTRACT FROM AUTHOR]

A unified one-dimensional model of an arc plasma in air, between copper electrodes, that includes the change of the gap distance is presented. The occurrence of multiple reversals of the electric field and the anode voltage drop is observed. The evolution of the spatial distribution of the electron and heavy particle temperatures with the gap distance and the opening speed is also studied. The model quantitatively predicts a number of plasma properties under conditions that are relevant to the contact separation in low-voltage switching devices. [ABSTRACT FROM AUTHOR]

Supersonic ion jets produced in vacuum arc discharges have a wide range of applications, where precise control of ion kinetic energy is crucial. However, a comprehensive understanding of the ion acceleration mechanism remains elusive, particularly regarding whether there is ion velocity separation in the vacuum spark stage. In this paper, a 1D spherical implicit particle-in-cell (PIC) with Monte Carlo collision (MCC) model is employed to investigate the ion velocity separation in multi-charged vacuum arc plasma with varying electrode bias voltages and plasma ion densities. The results show that ion kinetic energy can reach hundreds of electron volts due to continuous acceleration by the formed potential valley, which leads to ion velocity separation at low electrode bias voltage or low plasma density. An increasing electrode bias voltage flattens the potential valley, reducing the electric field acceleration. While increasing the plasma density deepens the valley and intensifies Coulomb collisions, resulting in nearly-equal velocities across ions in different charge states. These findings can theoretically explain the discrepancies observed in previous experiments regarding the dependence of the ion velocity on its charge state during the vacuum spark stage. [ABSTRACT FROM AUTHOR]

The objective of the current work was to investigate the creep behavior of functionalized graphene (f-GNF)-epoxy nanocomposite. Time and temperature-dependent mechanical behaviors were investigated by performing creep tests at three different stress levels and two different temperatures. Graphene produced by the electric arc discharge method was functionalized with Triton X-100 by a non-covalent method. Then, f-GNF-epoxy nanocomposites are produced by using the Three Roll Milling (3RM) method to eliminate nanofiller agglomeration. By performing quasi-static compression tests, stress levels for creep tests are determined as 50, 100, and 200 MPa to guarantee the viscoelastic deformation regime, around yield, and the viscoplastic deformation regime, respectively. The results indicate significant creep resistance in the nanocomposite with 0.1 wt% f-GNF. Depending on temperature and stress level, the effect of f-GNF is more pronounced at higher stresses and temperatures. f-GNFs have a significant effect on inhibiting the mobility of polymer chains, resulting improvements in the creep modulus. This indicates that thermally activated processes controlling the creep rate are in part inhibited by the presence of f-GNF. In the creep tests carried out for 2 h, a maximum improvement of 85% was observed in the creep modulus of epoxy-nanocomposite compared to pure epoxy at room temperature. [ABSTRACT FROM AUTHOR]

Electric arcs are a necessary heat source in many industrial processes that take place in Submerged Arc Furnaces (SAFs). Arcs exhibit non-linear electrical characteristics and behave in a complex manner. Therefore, an improved understanding of their behavior enables better control of furnace operation. Modeling of industrial arcs is a multiphysics process that involves simultaneously solving several coupled physical phenomena, such as electromagnetics, fluid dynamics, and heat transfer, including a radiative heat transfer from the plasma arc. Coupling fluid dynamics and electromagnetics is known as Magnetohydrodynamics (MHD). For practical applications, however, there are also simpler approaches to arc modeling, either based on simplified physical principles or empirical behavior. In this paper, a combined Cassie–Mayr model (CMM) and a channel arc model (CAM) are implemented and coupled with a submerged arc furnace electrical circuit model. The complete circuit model parameters such as resistances and inductances are estimated using modeling of a full size furnace, and then, actual measurements from a SAF are used to validate the models by comparing current and voltage waveform. Both models are then used to estimate harmonic distortion in a SAF for different arc current ratios, which should help operators to estimate the arc current in real time thus be able to lower and raise the electrode to keep operating conditions constant. [ABSTRACT FROM AUTHOR]

Supersonic coherent jets are widely in practice in steelmaking processes including electric arc furnaces (EAF). Injecting oxygen through such coherent jets plays a vital role in enhancing the liquid gas mixing and reaction rates leading to boosting energy efficiency. Several experiments and numerical simulations have been carried out to understand the physical phenomenon of the coherent jets and to predict the behavior of the jets. However, the research on pollutant formation in the coherent jets for steelmaking is limited. As the industry transitions toward reducing emissions, prediction of pollutant formation is crucial. This numerical study analyzes both methane shrouding coherent jets and hydrogen shrouding coherent jets and predicts the NOx (oxides of nitrogen) formation. It has been found that NO concentration dominates over N2O and NO2 and has the highest concentration around the jet. Although the NO concentration reaches as high as 1070 ppm at high-temperature region around the jet, it remains below 225 ppm along the fuel inlet axis. Also, it has found that the NOx concentrations increase along the radial direction up to 1.5 De from the jet central line and gradually decreases, whereas the NO concentration peaks at 15 D e along the jet axis in the downstream direction. [ABSTRACT FROM AUTHOR]

Modeling analysis of underwater pulsed arc discharge can predict the characteristics of plasma channels, providing theoretical guidance for the practical application of underwater pulsed discharge. Due to the complexity of experimental diagnostics for 'kA'-level underwater pulsed discharge, there is currently a lack of precise experimental data to support the initial value selection and result optimization of the modeling. This paper established a plasma channel model for underwater pulsed arc discharge. In conjunction with the Saha ionization equilibrium equation, the model was capable of simulating the current, pressure, temperature, and electron density of the channel after gap breakdown. By utilizing spectroscopic diagnostic data and a multi-objective optimization algorithm, the initial values and key parameters of the model were reasonably determined. The simulation results were in good agreement with the experimental diagnostic results, reasonably representing the trends in electron density and blackbody radiation temperature. Moreover, the model was applicable for reasonably explaining the emission spectral mechanism of the arc channel and shock waves prediction under different discharge conditions. [ABSTRACT FROM AUTHOR]

In this study, multi-walled carbon nanotubes (MWCNTs) were synthesized using the arc discharge method, and gold (Au) , and Au@MWCNT nanoparticles (NPs) were obtained via a rapid and cost-effective chemical reduction method. The performance of these catalysts in ethylene glycol (EG) fuel cells was investigated. According to the Transmission Electron Microscope (TEM) results, the Au particle size was determined to be 3.89 nm, and the MWCNT diameter was found to be 8.21 nm. For EG oxidation, current densities of 33.28 mA/cm2 for Au NPs and 171.28 mA/cm2 for Au@MWCNT NPs were obtained. This result demonstrates that the MWCNT support increased the electrocatalytic activity by a factor of 5.14. Long-term stability tests showed that the MWCNT support exhibited more stable and consistent characteristics and improved CO tolerance. Electrochemical Impedance Spectroscopy (EIS) testing revealed that the MWCNT-supported structure significantly enhanced charge transfer. These findings contribute significantly to the literature by demonstrating the potential for cost-effective production of carbon supported Au NPs, and their application in fuel cells. • MWCNT production using arc-discharge method. • Preparation of Au and Au@MWCNT catalysts and their use in ethylene glycol oxidation studies. • Au@MWCNT exhibits superior electrocatalytic activity towards ethylene glycol oxidation. • Synthesis of more stable catalyst for ethylene glycol oxidation. • Anode catalyst showing high potential for fuel cell applications. [ABSTRACT FROM AUTHOR]

Plasma-activated water can efficiently inactivate pathogenic microorganisms and is considered to be a potent disinfectant in the medical, food, and agricultural industries. In this study, the air discharged by the gliding arc was mixed with different gases including O2, ambient air, synthetic air, and N2 at different flow rates to produce the activated gases, which were then activated gases were inducted into saline to prepare plasma-activated saline (PAS). The gaseous reactive species in the activated gases were composed of NO, NO2, and N2O5 and the aqueous reactive species in the PAS included H2O2, NO2−, NO3–, ⋅ OH , and 1O2 with different intensities, while the inactivation effects of the PAS also varied with the type and the flow rates of the mixed gases in the activated gases. The inactivation effects of the PAS treated by the discharged air mixed with O2, ambient air, and synthetic air started to become weak after 3 h placement. Scavenger analysis demonstrated that the 1O2 played a critical role in the inactivation process. This study indicated that air discharged by the gliding arc mixed with different gases could regulate the reactive species and the biological effects of PAS, providing insight into the preparation of PAS applied for disinfection. [ABSTRACT FROM AUTHOR]

In this study, we introduce a theoretical model designed to explore both the photochemical and photothermal behavior of arc plasma radiation-induced ablation in gassing materials. We employ time-dependent density functional theory to analyze the photochemical behavior, while reactive force field molecular dynamics are used to explore the photothermal behavior. The phenomena, behavior and consequences of valence shell electronic excitation are analyzed in terms of ultraviolet (UV) absorption, electron-hole distribution, and Mayer bond order. Based on the photochemical findings, we apply a periodic electric field that corresponds to the vibration frequency of the permanent dipole moment to simulate infrared radiation, and convert UV photon energy into atomic kinetic energy to analyze UV radiation. This atomic-scale insight into photothermal behavior enables us to identify the final composition of ablation gases, including H2, CO, H2O, NH3, as well as specific cyanides, amines, and hydrocarbons. The results of the theoretical model and physical properties indicate that the concentration of hydrogen-containing gases in the ablation gas significantly affects the arc extinguishing capabilities of different polymers. Finally, we propose modification schemes suitable for polymers in power circuit breakers, considering UV absorption and smoke black production. Additionally, we present the potential application of theoretical models for calculating the ablation rate, necessitating further in-depth re-search. [ABSTRACT FROM AUTHOR]

To realize the overall optimization of electric arc furnace (EAF) steelmaking system, a multi‐objective optimization model including smelting cost, energy consumption per ton of steel, and carbon emission per ton of steel is established. The model is optimized by multi‐objective genetic algorithm to improve the charging structure. At the same time, the data in the optimal solution set are used to analyze the influence of the change of scrap ratio on smelting cost, carbon emission per ton of steel, and smelting cycle. According to the actual working conditions and the demand of steel plant, the optimized results are selected. Compared with the actual production data, the proportion of scrap steel increases to 50.9%, the ratio of molten iron decreases to 38.8%, the smelting cost per ton of steel decreases by 12 Yuan, the energy consumption per ton of steel decreases by 4%, the carbon emission per ton of steel significantly decreases by 13%, and the smelting cycle is shortened by 2 min, but at the cost of increasing the power consumption per ton of steel. The optimized results and the analysis of the change of scrap ratio provide reference for the optimization of EAF steelmaking system. [ABSTRACT FROM AUTHOR]

A direct current (DC) arc discharge is a widely used method for large-scale production of metal nanoparticles, core–shell particles, and carbon nanotubes. Here, the growth of iron nanoparticles is explored in a modified DC arc discharge. Iron particles are produced by the evaporation of an anode, made from low-carbon steel. Methane admixture into argon gas serves as a carbon source. Electron microscopy and elemental analysis suggest that methane and/or products of its decomposition adhere to iron clusters forming a carbon shell, which inhibits iron particle growth until its full encapsulation, at which point the iron core growth is ceased. Experimental observations are explained using an aerosol growth model. The results demonstrate the path to manipulate metal particle size in a hydrocarbon arc environment. [ABSTRACT FROM AUTHOR]

The present study establishes an experimental platform for investigating arc erosion and explores the erosion characteristics of Ti 3 AlC 2 material under a voltage of 10 kV in SF 6 /N 2 , SF 6 /CO 2 , and N 2 /CO 2 environments. Our findings reveal that the arc energy and duration exhibit a gradual increase in the sequence of SF 6 /N 2 , SF 6 /CO 2 , and N 2 /CO 2 , while the breakdown strength decreases. Scanning electron microscopy (SEM) and a three-dimensional laser confocal microscope were employed to observe uneven erosion morphology. Additionally, high-speed camera footage captures the arc bending and drifting phenomenon caused by Rayleigh-Taylor instability between the arc and gas. X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) analysis were utilized to characterize the composition of eroded surfaces. Erosion models were proposed for each mixed atmosphere along with comprehensive discussions on their underlying mechanisms. This work expands the application scope of MAX phase materials while providing a theoretical foundation for designing electrical contact materials. [ABSTRACT FROM AUTHOR]

Viscosity, density, and surface tension of an industrial electric arc furnace (EAF) slag from production of construction steel with varying SiO2 and Al2O3 contents are investigated using a rotating viscometer and the maximum bubble pressure method. In addition, influence of thermophysical properties on foaming index is discussed. To predict the behavior of the solid phase in the slag at different temperatures, thermodynamic calculations are performed using FactSage 8.1 software. The experiments demonstratethat SiO2 and Al2O3 act as network formers in the studied slag systems, resulting in increased viscosity values in the liquid‐dominant region and decreased density of the slag. The presence of alumina and silica altered the behavior of the slag in the liquid‐dominant region, shifting the breaking point of the slags. Furthermore, the addition of silica decreases the surface tension of the slag, confirming its role as a surfactant. However, the addition of Al2O3 increases the surface tension due to the high surface tension of pure alumina. Consequently, the foaming index of the slag can increase by ≈40%, primarily due to the polymerization of the slag. [ABSTRACT FROM AUTHOR]

The authors have described a method for synthesis of the crystalline phases of chromium boride CrB and CrB2 at atmospheric pressure without introducing additional modifiers improving the reactivity of the original charge. The formation of chromium borides was implemented under the action of an arc discharge with the original vacuum free dc electric-arc reactor. The influence of the parameters of the reactor on the phase composition of the obtained samples has been investigated. It has been established that the impact of an arch discharge of strength 200 A and duration 60 s on a mixture of Cr and B powders in a 1.0:2.55 atomic ratio ensures the formation of chromium diboride CrB2. The properties of the obtained powders have been studied by the methods of x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. [ABSTRACT FROM AUTHOR]

Ever since they have been studied, gas discharges have been classified by their visual appearance as well as by their current and voltage levels. Glow and arc discharges are the most prominent and well-known modes of discharges involving electrodes. In a first approximation, they are distinguished by their current and voltage levels, and current–voltage characteristics are a common way to display their relations. In this review, glow discharges are defined by their individual electron emission mechanism such as secondary electron emission by photons and primary ions, and arcs by their respective collective mechanism such as thermionic or explosive electron emission. Emitted electrons are accelerated in the cathode sheath and play an important role in sustaining the discharge plasma. In some cases, however, electron emission is not important for sustaining the plasma, and consequently we have neither a glow nor an arc discharge but a third type of discharge, the ohmic discharge. In part 1 of this review, these relationships are explained for quasi-stationary discharges, culminating with updated graphical presentations of I–V characteristics (Figs. 15 and 16). In part 2, further examples are reviewed to include time-dependent discharges, discharges with electron trapping (hollow cathode, E × B discharges) and active anode effects. [ABSTRACT FROM AUTHOR]

This investigation conducted an experimental study of flow control in a Mach 2.5 cavity combustor using arc plasma energy deposition (APED), implemented both with and without injection. APED was produced by a pulsed arc discharge plasma actuator at frequencies of 5, 10, 15, and 20 kHz. The objective is to elucidate the influence and underlying mechanisms of APED on the flow dynamics by statistically evaluating time-resolved schlieren images and monitoring pressure fluctuations throughout the control process. The findings indicate that APED significantly modifies the energy distribution across unsteady modes and alters the pressure distribution within the flow field. In scenarios without injection, high-frequency discharge triggers oscillations in the shear layer; the impact of precursor shocks and thermal bubbles diminishes the magnitude and fluctuations of both shear layer-induced and internal shocks. Conversely, in the injection scenario, high-frequency discharge, in conjunction with oscillations of the boundary layer and bow shocks, amplifies the oscillation amplitude and frequency of jet vortex shedding. Additionally, APED intensifies the pulsation and penetration depth of the jet, which is essential for enhancing the mixing efficiency of the incoming flow with fuel. The effectiveness of the control is positively correlated with the actuator's discharge frequency, or its average power, within the confines of this study. [ABSTRACT FROM AUTHOR]

Shock–shock interactions (SSIs) are widespread in hypersonic vehicles. The mutual interaction between multiple shock waves can result in severe pressure loads and increase the thermal load. The SSI induced by a double wedge configuration is a classical problem. This paper describes a novel U-electrode surface arc actuator that produces a supermultichannel array surface arc discharge under hypersonic conditions. High-speed schlieren measurements are used to investigate the SSI induced by the hypersonic double wedge and plasma control under Mach 8 flow conditions. The results show that the shock wave array induced by the plasma forms a virtual compression surface. This surface deforms the shock wave induced by the first wedge, and the oblique shock wave in front of the secondary wedge and the SSI region disappear due to the uplift and hot gas mass disturbance from the impact. Because the applied actuation frequency is higher than the characteristic frequency of the base flow field, the high-frequency pulsations of the shock wave are controlled by the plasma actuation. Additionally, the low-frequency instability is suppressed. Thus, the aerodynamic load and low-frequency instability of the double wedge configuration under high-Mach-number conditions are effectively regulated. [ABSTRACT FROM AUTHOR]

In this work, to establish the oxidation resistance for graphite in the air atmosphere with temperatures ranging from 700 to 1000 °C, an innovative multi-component, dual-layer coating was developed. The coating consists of two layers with a total thickness of around 250 μm. The first layer was consisted of B2O3 with SiO2 and ZnO, while the second layer included SiC with silicon as an additive. Through scanning electron microscopy (SEM) images and elemental maps, alongside heat treatment experiments at 1000 °C, which resulted in only a 6% weight loss, it was evident that the coating was effectively applied and performed exceptionally well. Moreover, cyclic heat treatment experiments confirmed the coating's durability and thermal stress resistance, with minimal weight reduction results. Applying these coatings is uncomplicated, and the materials are readily available, ensuring cost-effectiveness. [ABSTRACT FROM AUTHOR]

We discuss 1D, 2D and 3D bifurcation diagrams of two nonlinear dynamical systems: an electric arc system having both chaotic and periodic steady-state responses and a cytosolic calcium system with both periodic/chaotic and constant steady-state outputs. The diagrams are mostly obtained by using the 0–1 test for chaos, but other types of diagrams are also mentioned; for example, typical 1D diagrams with local maxiumum values of oscillatory responses (periodic and chaotic), the entropy method and the largest Lyapunov exponent approach. Important features and properties of each of the three classes of diagrams with one, two and three varying parameters in the 1D, 2D and 3D cases, respectively, are presented and illustrated via certain diagrams of the K values, − 1 ≤ K ≤ 1 , from the 0–1 test and the sample entropy values S a E n > 0 . The K values close to 0 indicate periodic and quasi-periodic responses, while those close to 1 are for chaotic ones. The sample entropy 3D diagrams for an electric arc system are also provided to illustrate the variety of possible bifurcation diagrams available. We also provide a comparative study of the diagrams obtained using different methods with the goal of obtaining diagrams that appear similar (or close to each other) for the same dynamical system. Three examples of such comparisons are provided, each in the 1D, 2D and 3D cases. Additionally, this paper serves as a brief review of the many possible types of diagrams one can employ to identify and classify time-series obtained either as numerical solutions of models of nonlinear dynamical systems or recorded in a laboratory environment when a mathematical model is unknown. In the concluding section, we present a brief overview of the advantages and disadvantages of using the 1D, 2D and 3D diagrams. Several illustrative examples are included. [ABSTRACT FROM AUTHOR]

Noninvasive imaging of circuit breakers under short-circuit testing is addressed by recording the magnetic field produced over an array of external sensors and by solving an inverse problem to identify the causing current distribution. The temporal and spatial resolution of the sensing chain are studied and implemented in a physical set-up. A wire model is adopted to describe electrical current distribution. Additionally, the simpler, more direct approach to evaluating the passage of electric current in front of sensors is proposed. The dynamics of suitable approximating models of the electric arc that forms across contacts is obtained and agrees with multi-physical simulations and with experimental time histories of current and voltage. The two methods are flexible and allow the analysis of different types of circuit breakers. [ABSTRACT FROM AUTHOR]

The C4F7N/CO2 mixture is considered one of the most promising alternatives to sulfur SF6. Recent studies have shown that the addition of O2 to the C4F7N/CO2 mixture can suppress carbon precipitation following electric arc discharges. This paper conducts arc-burning experimental research on SF6, 10%C4F7N/90%CO2, and 10%C4F7N/85%CO2/5%O2 mixtures. Measurements were taken of the arc voltage and arc current under a 10 kA breaking current for these three gases. Additionally, the pressure at the nozzle throat during arc and cold flow conditions, as well as the pressure in the storage chamber, were measured. The post-arc current and Rate of Rise of Recovery Voltage (RRRV) for the three gases were calculated. The study also compared the solid precipitates in the gas medium after multiple arc-burning experiments. The results indicate that adding O2 to the C4F7N/CO2 mixture can increase the pressure at the nozzle throat during the arc phase, and the inclusion of O2 has minimal impact on the peak arc-extinguishing voltage and critical RRRV. It is hypothesized that a small amount of oxygen has a negligible effect on the thermal recovery properties of the C4F7N/CO2 mixture, while also inhibiting the precipitation of carbon following electric arc discharges. This research could provide a reference for developing and optimizing eco-friendly high-voltage circuit breakers. [ABSTRACT FROM AUTHOR]

An arc glow discharge device was used to prepare a helical carbon fiber skeleton with helical carbon fibers hooked to each other by spraying a hydrogen and ethanol mixture onto the iron wire substrate through the discharge area, using anhydrous ethanol as the carbon source. The samples were characterized by SEM, EDS, Raman and XPS. A growth mechanism of helical carbon fiber driven by C sp3 was proposed. The various growth modes of carbon fiber during the formation of carbon fiber skeleton were investigated. A ring appearance that indicated a change in the direction of carbon fiber growth was observed. And double helical carbon fiber was constructed from single helical carbon fiber in two ways. Super-large carbon fiber with a diameter of about 13 μm was observed, and it was speculated that this super-large carbon fiber is the backbone of the carbon fiber skeleton. The mechanical properties of the carbon fiber skeleton are isotropic. [ABSTRACT FROM AUTHOR]

This article explores the decarbonization of industries with high carbon dioxide emissions, specifically focusing on the steel industry. It discusses the replacement of traditional blast furnaces with MIDREX® reactors operated with hydrogen as a reducing agent. However, the article presents an alternative method using ammonia that is cost-effective. It introduces three industrial projects aimed at reducing CO2 emissions in steel production and discusses different methods of direct reduction of iron oxide to produce iron, including the use of carbon monoxide and hydrogen gas, as well as ammonia. The text also mentions the optimization of high-temperature electrolysis of water and collaborations between companies and universities for hydrogen production. The use of ammonia as a means of transporting hydrogen is highlighted for its lower cost. The article concludes with a description of a laboratory experiment for students to explore the direct reduction of iron oxide using ammonia, providing safety considerations and potential applications in the context of decarbonizing steel production. [Extracted from the article]

Purpose: The purpose of this study is to investigate the influence of varying concentrations of nano-SiO2 particle doping on the structure and properties of the micro-arc oxidation (MAO) coating of 7075 aluminum alloy. This research aims to provide novel insights and methodologies for the surface treatment and protection of 7075 aluminum alloy. Design/methodology/approach: The surface morphology of the MAO coating was characterized using scanning electron microscope. Energy spectrometer was used to characterize the elemental content and distribution on the surface and cross section of the MAO coating. The phase composition of the MAO coating was characterized using X-ray diffractometer. The corrosion resistance of the MAO coating was characterized using an electrochemical workstation. Findings: The results showed that when the addition of nano-SiO2 particles is 3 g/L, the corrosion resistance is optimal. Originality/value: This study investigated the influence of different concentrations of nano-SiO2 particles on the structure and properties of the MAO coating of 7075 aluminum alloy. [ABSTRACT FROM AUTHOR]

The increase in high-precision radiation therapy, particularly volumetric-modulated arc therapy (VMAT), has increased patient numbers and expanded treatment sites. However, a significant challenge in VMAT treatment planning is the inconsistent plan quality among different planners and facilities. This study explored the use of dose-volume histogram (DVH) prediction tools to address these disparities, specifically focusing on RapidPlan (Varian Medical Systems) and PlanIQ (Sun Nuclear). RapidPlan predicts achievable DVHs and automatically generates optimization objectives. While it has demonstrated organ-at-risk (OAR) dose reduction benefits, the quality of the plan used to build its model significantly affects its predictions. On the other hand, PlanIQ offers ease of use and does not require prior model-building. Five planners participated in this study, each creating two treatment plans: one referencing RapidPlan and the other using PlanIQ. The planners had the freedom to adjust parameters while referencing the DVH predictions. The plans were evaluated using "Plan Quality Metric" (PQM) scores to assess the planning target volume excluding the rectum and OARs. The results revealed that RapidPlan-referenced plans often outperformed PlanIQ-based plans, with less interplanner variability. PlanIQ played a pivotal role in the construction of the RapidPlan model. This study is the first to compare plans generated by multiple planners using both tools. This study provides insights into optimizing treatment planning by considering the characteristics of both RapidPlan and PlanIQ. [ABSTRACT FROM AUTHOR]

In this study, we investigate the impacts of the 17 March 2013 strong geomagnetic storm on the wholly coupled Solar Wind‐Magnetosphere‐Ionosphere‐Thermosphere system‐of‐systems. Obtained from multipoint observations, our new results show (1) the solar‐wind Alfven waves propagating antisunward in the sheath region and (2) oscillating solar wind interplanetary magnetic field (IMF) and electric (E) field (IEF EY) that powered (3) rigorous dayside and nightside flux transfer events (FTEs) when (4) the nightside‐reconnection‐related short circuiting led to fast‐time Subauroral Ion Drifts (SAID) and Subauroral Polarization Streams (SAPS) E field development across the inner‐magnetosphere plasmapause where the solar‐wind Alfven waves (4) transitioned into kinetic Alfven waves (5) fueling the hot zone. Also, the antisunward solar‐wind Alfven waves (6) drove enhanced large‐scale region‐1 field‐aligned currents creating (7) undershielding conditions (8) allowing the dawn‐to‐dusk convection E field's earthward penetration, and (9) generated increased solar‐wind kinetic energy, which became deposited (10) to the ionosphere increasing the ionospheric electron temperature (by the downward flowing suprathermal electron fluxes) and (11) to the thermosphere oscillating the neutral winds and increasing the neutral temperature, and finally leading to (12) the development of bright stable auroral red (SAR) arcs in (13) the enhanced SAID/SAPS flow channels (FCs) developed during FTEs, (14) demonstrated with FC‐2 and FC‐3 events, in the enhanced polar convection that (15) the Rice Convection Model could reproduce. Finally, we conclude the antisunward‐propagating large‐amplitude solar‐wind Alfven waves' ultimate significant role in creating the favorable conditions for the various phenomena documented with the new observational results (1–14). Plain Language Summary: We investigate the wholly coupled Solar Wind‐Magnetosphere‐Ionosphere‐Thermosphere (SW‐M‐I‐T) system‐of‐systems operational during the 17 March 2013 strong geomagnetic storm. Results show the development of two significant phenomena in the coupled SW‐M system: (a) the region 1 field‐aligned currents and (b) the antisunward solar‐wind Alfven waves. While (a) created undershielding conditions allowing the dawn‐to‐dusk electric field (Edd) earthward propagation, (b) drove (B field, E field, wind) oscillations and generated kinetic energy (up to ∼400 TW) that became deposited (up to ∼5 TW) into the magnetosphere efficiently (up to ∼2.5%). In the coupled M‐I system, the kinetic energy drove reconnection events while the Edd convected the plasma in a two‐cell pattern. During nightside reconnection, the earthward injected ring current (RC) protons led to the development of the hot zone and conjugate large‐scale E fields near/across the plasmapause, while the downward heat flux channeled into the ionosphere elevated the electron temperature (Te). In the coupled I‐T system, the elevated Te increased the thermospheric neutral temperature (Tn) and both (Te and Tn) ignited the stable auroral red arc while the thermospheric neutral winds became oscillatory because of the antisunward solar‐wind Alfven waves that acted as the ultimate driver of the wholly coupled SW‐M‐I‐T system‐of‐systems operational. Key Points: Solar‐wind Alfven waves led to SAID/SAPS development via reconnection and transitioned into kinetic Alfven waves fueling the hot zoneEnhanced R1 FACs led to undershielding permitting the dawn‐to‐dusk convection E field's earthward penetration (to L ≈ 6 RE) on the nightsideOscillating thermospheric neutral winds and neutral temperature increase led to the development of bright SAR arcs [ABSTRACT FROM AUTHOR]

The development of super high-rise building projects has become crucial for mitigating land shortages in rapidly growing urban areas. Super high-rise steel structures, particularly RC core wall-steel frame systems, have become the preferred choice due to their superior performance, high prefabrication level, and construction efficiency. Despite their benefits, super high-rise buildings face challenges related to higher energy consumption and carbon emissions. Consequently, it is important to analyze the carbon emissions of these buildings throughout their lifecycle and propose low-carbon construction strategies. A carbon emission analysis focused on super high-rise buildings with RC core wall-steel frame structures is conducted in this study. A carbon emission analysis model is constructed based on BIM-enabled LCA through a real-world case study. The emission factor method is combined with the BIM model to calculate carbon emission. Furthermore, carbon emissions across various construction strategies are compared, with a particular focus on the manufacturing processes of the main materials. The results indicate that incorporating admixtures in concrete, along with adopting the electric arc furnace (EAF) method and utilizing recycled scrap steel in steel manufacturing, significantly reduces the carbon emissions of the buildings. Lastly, effective low-carbon approaches for these buildings are proposed. [ABSTRACT FROM AUTHOR]

Steel mill dust (SMD), produced by electric arc furnaces, is a highly polluting industrial waste due to its high content of metals (Zn, Fe, and Pb) and fine particle size (ca. 5.4 µm). This residue can be valorized to recover Zn using pyro and hydrometallurgical methods, with hydrometallurgy offering greater selectivity and lower energy costs. However, composition of SMD presents a challenge in identifying an optimal leaching agent. This study investigates the preferential extraction of Zn using two leaching agents, namely 150 g L−1 (1.5 M) phosphoric acid (H3PO4) and 240 g L−1 (6 M) sodium hydroxide (NaOH), in a two-stage leaching process (80 °C). Metallic Zn from the alkaline pregnant solution was recovered by electrodeposition (750 A/m2, graphite anode, stainless-steel cathode) and smelting (450 °C). The samples of SMD contained 26.3% Zn, 20.1% Fe, and 0.9% Pb, in compounds such as magnetite (Fe3O4), zincite (ZnO), and franklinite (ZnFe2O4). Each leaching agent successfully attained a 99% Zn recovery, demonstrating the proposed procedure's high efficacy. However, H3PO4 leached also Fe and corroded the cathode during electrodeposition, thereby restricting the final recovery of metallic Zn. NaOH demonstrated greater selectivity for Zn over Fe and Pb, producing high-purity Zn deposits on the cathode by electrodeposition and 99% metallic zinc by smelting. [ABSTRACT FROM AUTHOR]

Carbon nanotubes, as carbon allotropes distinguished by their intricate structures and exceptional physicochemical properties, have demonstrated substantial progress in recent years across diverse domains, including energy production, chemical synthesis, and environmental preservation. They exhibit notable attributes such as high thermal stability, superior adsorption capacity, and a substantial specific surface area, rendering them superb catalyst supports. Particularly in electrochemical energy storage, CNTs are extensively employed in supercapacitor electrodes owing to their elevated electrical conductivity, mechanical robustness, and electrocatalytic prowess, which facilitate significant energy storage capabilities. Their intricate pore architecture and reactive sites make functionalized carbon nanotubes well suited for synthesizing composite materials with diverse components, which are ideal for sequestering carbon dioxide from both atmospheric and indoor environments. This review presents a comprehensive examination of carbon nanotube synthesis methodologies, encompassing chemical vapor deposition, arc discharge, and laser ablation, and evaluates their impacts on the structural and functional properties of carbon nanotubes. Furthermore, this article underscores the applications of carbon nanotubes in fields such as fuel cells, photocatalysis, ammonia synthesis, dry methane reforming, Fischer–Tropsch synthesis, and supercapacitors. Despite the considerable potential of carbon nanotubes, their manufacturing processes remain intricate and costly, impeding large-scale industrial production. This review concludes by addressing the challenges in fabricating carbon nanotube composites and outlining future development prospects. [ABSTRACT FROM AUTHOR]

The decarbonisation of the steel and cement industry is of utmost importance in tackling climate change. Hence, steel production in modern integrated steel mills will be shifted towards electric arc furnaces in the future, in turn causing dwindling supplies of blast furnace slag, which is used as a supplementary cementitious material inter alia to reduce the CO2 emissions of cement production. Achieving a sustainable circular steel and building material economy requires the valorisation of currently landfilled steel slags and investigating utilisation options for electric arc furnace slag, which is increasingly being generated. For this purpose, different metallurgical residues and by-products were treated by carbothermal reduction in an inductively heated graphite crucible and then rapidly cooled by wet granulation, yielding a slag fraction similar to granulated blast furnace slag and a metal fraction valuable as a secondary raw material. A spreadsheet-based model was developed to calculate residue combinations to accomplish target compositions of the slag and metal fractions to fulfil previously identified requirements of the targeted cementitious and ferrous products. The results demonstrate the high accuracy of the model in predicting the properties (e.g. main oxide composition) of the generated slag and metal fraction, which fulfil the needed requirements for their use as (i) a supplementary cementitious material and (ii) a secondary raw material in steel production. [ABSTRACT FROM AUTHOR]

Titanium alloy has been widely used in several industrial applications because it has superior mechanical properties and good corrosion resistance. Titanium alloys are also widely used as an implant material, and the Ti-6Al-4 V is one of the most popular. Recent research proves that the release of Al and V ions from the Ti-6Al-4 V alloy can cause long-term health problems. Therefore, Titanium alloys without Aluminum and Vanadium were developed as implant material. In this paper we develop Ti-30Nb-xSn with x = 0, 2, 5 dan 8% (%wt.) as implant material. The alloying melted in an electric arc vacuum furnace, homogenised at 1000°C holding time 5 h with ice water quench. The specimen was characterised by a Vickers hardness tester, optical metallography, SEM-EDS, XRD, ultrasonic test to investigate the modulus of elasticity and corrosion testing with the potentiodynamic polarisation method. The optimum results are reached at Ti-30Nb-5Sn alloys where the β-phase optimum with modulus elasticity valued 112 GPa, and hardness Vickers valued 312.2 HV. In addition, the addition of Sn can increase corrosion resistance optimum with valued 90.11 × 10−6mmpy. [ABSTRACT FROM AUTHOR]

Electric arc furnace (EAF) slag is a coproduct of steel production used primarily for construction purposes. Some applications of EAF slag result in residential exposures by incidental ingestion and inhalation of airborne dust. To evaluate potential health risks, an EAF slag characterization program was conducted to measure concentrations of metals and leaching potential (including oral bioaccessibility) in 38 EAF slag samples. Arsenic, hexavalent chromium, iron, vanadium, and manganese (Mn) were identified as constituents of interest (COIs). Using a probabilistic risk assessment (PRA) approach, estimated distributions of dose for COIs were assessed, and increased cancer risks and noncancer hazard quotients (HQs) at the 50th and 95th percentiles were calculated. For the residents near slag‐covered roads, cancer risk and noncancer HQs were <1E − 6 and 1, respectively. For residential driveway or landscape exposure, at the 95th percentile, cancer risks were 1E − 6 and 7E − 07 based on oral exposure to arsenic and hexavalent chromium, respectively. HQs ranged from 0.07 to 2 with the upper bound due to ingestion of Mn among children. To expand the analysis, a previously published physiologically based pharmacokinetic (PBPK) model was used to estimate Mn levels in the globus pallidus for both exposure scenarios and further evaluate the potential for Mn neurotoxicity. The PBPK model estimated slightly increased Mn in the globus pallidus at the 95th percentile of exposure, but concentrations did not exceed no‐observed‐adverse‐effect levels for neurological effects. Overall, the assessment found that the application of EAF slag in residential areas is unlikely to pose a health hazard or increased cancer risk. [ABSTRACT FROM AUTHOR]

The main goal was to investigate the ability of a non-thermal plasma reactor with gliding arc discharge to remove diesel exhaust particulates (DEPs). A conventional knife-shaped LTP GA (low-temperature plasma gliding arc) reactor was utilized. The following three cases were studied: 140 L/min, 70 L/min, and 14 L/min of air drawn through the reactor, and diesel exhaust fumes were sampled continuously. They were assayed in terms of concentration and number particle size distribution. The higher the residence times, the higher the energy input that may be utilized for DEPs' removal. The reactor performance definitely lowered the concentration of DEPs (250–580 nm) and altered their number size distribution. There was no effect on the number concentration, nor the particle size distribution, of DEPs of 10–250 nm in size. Regarding the effectiveness of DEPs' removal, decreasing the flow rate from 140 L/min to 70 L/min somehow altered the values. Achieving the airflow of 14 L/min led to a substantial improvement (even to a fourfold increase for 300–480 nm particles). Non-thermal plasma reactors with gliding arc discharge may be successfully adapted to the process of DEP treatment. Their performance may be optimized by adjusting the airflow at the inlet of the reactor to guarantee the longest aerosol residence times and the highest removal efficiency. [ABSTRACT FROM AUTHOR]

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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny 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.)