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Chemiluminescence of OH∗ is commonly employed as an optical indicator for the combustion process. It is widely recognized that the generation of OH∗ in hydrogen flames is primarily governed by the reaction H + O + M=>OH∗+M. In this study, the time histories of OH∗ chemiluminescence from the A→X band around 308 nm were recorded behind reflected shock waves for stoichiometric and lean H 2 /O 2 mixtures highly diluted in argon over the temperature range of 1130–3150 K and at the pressure of approximately 0.9 atm. Based on the time histories of OH∗ chemiluminescence, the best-fit reaction rate coefficient for the reaction H + O + M=>OH∗+M was determined as k = 3.17 × 1027exp(-121968 cal mol−1/RT) + 2.25 × 1017exp(-4246 cal mol−1/RT) cm6 mol−2 s−1 over the temperature range studied. Furthermore, by using the current rate coefficient in mechanism predictions, the predicted time histories and relative peak intensities of OH∗ chemiluminescence are in good agreement with experimental results reported in literature. • The time histories of OH∗ chemiluminescence up to 3150K are recorded. • The rate coefficient for H + O + M=>OH∗+M is determined. • The OH∗ sub-mechanism with the fitted rate coefficient has been verified. [ABSTRACT FROM AUTHOR]

Owing to the energy-efficient attributes of electrochromic technology, there has been a growing emphasis on the fabrication of electrochromic devices with high-contrast and stable performance. As an electron donor, the deliberate incorporation of oxygen vacancies into an electrochromic material is poised to significantly elevate the film's electrochromic characteristics. In this study, we successfully synthesized one-dimensional W 18 O 49 nanowires thin films with enhanced oxygen vacancies using a straightforward combination of solvothermal reactions and annealing in Ar. In comparison to films annealed in air, those treated in argon (Ar) exhibited a higher concentration of oxygen vacancies, resulting in improved light absorption characteristics. The optimal annealing conditions were determined to be 400 °C for 40 min. Under these conditions, the thin film demonstrates enhanced electrochromic performance, exhibiting a notable 71.6% modulation in transmittance, a 27.2% increase compared to the air condition. It displays a rapid response time (T b = 3.3 s, T c = 3 s), high coloration efficiency (CE = 55.9 cm2 C−1), and excellent cycling stability (with a ΔT retention rate of 93.9% after 750 cycles). [ABSTRACT FROM AUTHOR]

Mo 2 AlB 2 is a new and metastable phase in the MAB phase family. The lamellar Mo 2 AlB 2 compound is considered to be an optimal candidate for preparing 2D MoB nanosheets. However, studies have less focused on its thermostability as compared with other MAB phases. In this work, the thermal stability of Mo 2 AlB 2 was studied under Ar atmosphere to understand its limited applications. The results showed that Mo 2 AlB 2 slowly decomposed at above 800 °C, but completely decomposed into MoB and Al at 1100 °C for only 0.5 h. Based on the experimental results and density functional theory calculations, the decomposition mechanism of Mo 2 AlB 2 phase was analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] The results of shock-tube measurements of acetylene concentration and characteristics of the ensemble of soot particles during the pyrolysis of benzene, ethylene, ethylene–methane and ethylene–propane diluted with argon are compared with the predictions of the unified kinetic model of soot formation implemented in the MACRON program based on the Galerkin method. The simulation results demonstrate good agreement with experimental data for the pyrolysis of ethylene alone and with the specified additives, thereby confirming the two route mechanism of soot nuclei formation. The agreement for benzene pyrolysis is less satisfactory. [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]

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]

SiC ceramic was fabricated by spark plasma sintering of β-SiC powder and Y 2 O 3 -MgO additives in argon. The effects of β→α phase transformation of SiC on microstructure and thermal conductivity of densified bulks were systematically investigated, in comparison to the counterparts using α-SiC as starting powder. The β→α phase transformation led to a "unimodal to bimodal" transition in grain size distribution. After sintering at 1850 oC, the incomplete β→α phase transformation induced the appearance of β/α heterophase boundary with strong effect of phonon-scattering. After sintering at 2050 oC, the completion of β→α phase transformation resulted in enlarged grains and disappearance of β/α heterophase boundary in SiC ceramic. The lattice oxygen content was decreased primarily by enhanced grain growth and oxygen picking-up of sintering additives, and possibly some contribution from β→α phase transformation. The optimized microstructure enabled SiC ceramic to obtain a remarkable increase in thermal conductivity from 126 to 204 W/mK after the replacement of α-SiC by β-SiC as starting powder and the accomplishment of β→α phase transformation. [ABSTRACT FROM AUTHOR]

Optical erbium oxide (Er 2 O 3) films were prepared by radio frequency (RF) magnetron sputtering to improve the infrared (IR) transmittance of chemical vapor deposition (CVD) diamond. This study aims to analyze the microstructure, composition and optical properties of Er 2 O 3 anti-reflection films at various oxygen/argon ratios. Atomic force microscopy (AFM) analysis was used to detect the surface morphology of chemical oxidation CVD diamond and Er 2 O 3 films. The surface roughness of Er 2 O 3 films decreased with an increase in the oxygen/argon ratio. The crystalline structure of Er 2 O 3 films was analyzed by using X-ray diffraction. Meanwhile, a gradual decrease was observed when the crystallite size and its strain were calculated. This was due to the transformation of partial phases from monoclinic to cubic structures. The chemical composition of Er 2 O 3 films was analyzed by X-ray photoelectron spectroscopy (XPS). The surface of Er 2 O 3 films underwent a transformation from the unstable structure of nonstoichiometric Er 2 O 3-x to the stable structure of Er 2 O 3 with an increase in the level of oxygen. Defect behavior was determined by transmission electron microscopy (TEM). Specifically, dislocation and twinning were observed at a high oxygen/argon ratio, which was mainly attributed to the competitive growth of polycrystalline Er 2 O 3 films. The optical constants of Ψ and △ were shifted to lower wavelengths with increase oxygen/argon ratio. The maximum transmittance of the Er 2 O 3 /diamond film was 79% in the long-wavelength infrared (LWTR) range of 8–12 μm at an oxygen/argon ratio of 1:35. This value was significantly higher than that of the high oxygen/argon ratio. The present study concludes that a low oxygen/argon ratio promotes the growth and IR transmittance of Er 2 O 3 films. [ABSTRACT FROM AUTHOR]

In this study, the reaction characteristics of reduction of calcined dolomite with ferrosilicon under argon flow to produce magnesium were studied by conducting experiments Pidgeon pellets were used to study the effect of reduced temperature, argon flow, and reduced time on the conversion of calcined dolomite reduction by ferrosilicon. The results show that the conversion significantly increases with the increase in the reduction temperature and reduction time. The conversion first increases and then decreases with the increase in argon flow. The highest conversion was obtained when the argon flow rate was 3 L·min−1, and a nearly spherical shape, nanoscale magnesium powder was obtained. Then the characters of the circulating argon entrainment process were numerically studied by ANSYS Fluent 17. A physical model of multilayer pellet arrangement was established, and a numerical calculation model of chemical reaction, radiation, heat conduction, and convection heat transfer was constructed. This confirms that high-temperature argon can effectively strengthen the heat exchange between pellets, improve the heat transfer efficiency, and facilitate the pellets to react quickly. When the conversion is 80%, the production efficiency increased by about 28.6%. In addition, the magnesium production efficiency showed an increase tendency with the increase of the argon inlet flow rate. [ABSTRACT FROM AUTHOR]

Chemical vapor reaction (CVR) fabricated-SiC samples were irradiated with 300 keV Ar2+ ions in the fluence range of 5 × 1015 –1 × 1017 ions·cm−2. Raman spectrum and grazing incidence X-ray diffraction analysis display amorphization and lattice expansion of the irradiated CVR-SiC. Transmission electron microscope observations show that small black spots with an average diameter of 1.5 nm are formed at a low fluence of 5 × 1015 ions·cm−2. Moreover, large argon bubbles with an average diameter of 15.1 nm are formed at a high fluence of 1 × 1017 ions·cm−2, and the Ar concentration threshold for bubble formation is 8.83 at.%. The influence of implantation amorphization and Ar atom migration in CVR-SiC on the formation of Ar bubbles is discussed. The results provide a basis for understanding the noble-gas-induced irradiation behavior of CVR-SiC for preventing irradiation damages in future nuclear applications. [ABSTRACT FROM AUTHOR]

• Worldwide 1st time binder based 3D-printed (FGF) biodegradable Mg-based (MgGd-alloy) bone scaffolds. • Obtaining an as printed interconnected open porosity for cell ingrownth and vascularisation. • Mechanical behavior of experimental test and simulation shows good agreement. In this study, a binder based 3D-printing technology viz. Fused Granular Fabrication (FGF) technique was used to produce interconnected and open porous Mg-6.3Gd bone scaffolds for compression test analyses. The consolidation of the green parts (as printed scaffolds) was performed using solvent debinding in cyclohexane and subsequent conventional sintering in argon atmosphere. Compression tests were performed on as sintered parts. Additionally, a simulation strategy was developed for modeling the compression behavior of the sintered parts, utilizing the data from the experimental results. The experimental compression test results and the simulation strategy for the compression behavior of the 3D-printed scaffolds demonstrated good agreement. [Display omitted] [ABSTRACT FROM AUTHOR]

We measured He and Ar in fresh peridotites from the Twin Sisters massif, Washington USA. 3He/4He ratios measured on >35 samples are highly variable (∼0.8 to ∼6 times the atmospheric ratio, R A). Step-heating of a subset of these samples in every case reveals a low 3He/4He component (∼1 R A) released at <1000 °C and a high 3He/4He component (>3 R A) above that temperature, but these components are not effectively isolated by crushing and powder fusion analysis. He-Ar systematics indicate an intimate association of two fluid-inclusion hosted components in the peridotites. The first is a ∼6 R A mantle component that is released at higher temperatures during step heating and is more abundant in dunite bands than surrounding harzburgites. The second component, released at low temperatures, has a 3He/4He ratio of 1.0 ± 0.5 R A, atmospheric 40Ar/36Ar, and 4He/40Ar far above atmospheric. It appears to be a mixture of mantle and radiogenic He sources introduced during obduction-related serpentinization, sometimes invisible, by surface-derived waters enriched with deeply-sourced helium. These data indicate that mantle noble gas signatures can be retained in lithospheric peridotites against both diffusive loss and radiogenic ingrowth over at least 108 year timescales, likely due to concentration and immobilization of He in fluid inclusions. However, the mantle signature can be greatly modified by pervasive and potentially cryptic fluid alteration during emplacement. [ABSTRACT FROM AUTHOR]

The effects of pulse frequency on microstructure and properties of in-situ TiC reinforced Fe-based tungsten argon arc layers were studied. The results showed that under the same heat input, with the increases of the pulse frequency, the macroscopic forming quality improved, the particle size of TiC and the grain size of the Fe-based layer's matrix increased first and then decreased. TiC changed from equiaxed into agglomerated and finally into fine particles. TiC agglomerated obviously led to a poor corrosion resistance, and plastic stress accumulated in the gaps at 27 Hz. At 729 Hz, TiC dispersed evenly with the smallest grain size, and the layer possessed the highest hardness and best corrosion resistance. Moreover, the plastic stress distributed uniformly, which was conducive to suppressing plastic deformation. This study provides an economical method for preparing wear-corrosion resistant Fe-based cladding layers that used in the remanufacturing industry. [ABSTRACT FROM AUTHOR]

There is a growing need to consider alternative propellants for operation in Hall thrusters, away from the conventional legacy of using xenon. This is particularly the case for small Hall thrusters; which are growing exponentially in their use, whilst needing to be operational on inexpensive propellants. Alternative propellants include condensable propellants (i.e., zinc and iodine), or other gaseous propellants (krypton, argon, and nitrogen (N 2)) - which are the focus here. A low power (nominally 100 W) miniature Hall thruster has been designed and manufactured based upon standard scaling laws, with specific considerations for operation with the use of alternative gaseous propellants, and with an attempted novel field topology. The thruster, designated the HEKT-100, was designed to be a low power magnetically shielded thruster to operate on krypton, however the level of shielding present is unknown or tested. Here the thruster has subsequently been operated on xenon, krypton, argon, and diatomic nitrogen successfully, with an unstable operation with neon. The thruster is operated at discharge powers of between 30–810 W. Using a pendulum thrust balance, the thruster performance was measured across a wide range of flow rates, magnetic field strengths, and anode discharge voltages. The performance measured for xenon, krypton, argon, and diatomic nitrogen respectively was, peak thrusts of 12.6 mN, 6.9 mN, 6.6 mN and 5.7 mN, anode efficiencies up to 26.3%, 15.2%, 9.6% and 5.4%, and specific impulses up to 2160 s, 1730 s, 1390 s, and 1000 s. This dataset and the following analysis provides one of the few times a comprehensive selection of alternative gaseous propellants have been tested within the same thruster and compared directly with unchanged geometry or set-up. • Operation of a low power Hall thruster on xenon, krypton, argon, neon, and nitrogen. • Hall thruster scaling considerations for alternative propellant. • Sub-kilowatt ignition with diatomic Nitrogen, and Neon. • Nitrogen operation similar in performance to argon. [ABSTRACT FROM AUTHOR]

SiC–MgAl 2 O 4 –Al composites were prepared using SiC, MgAl 2 O 4 , corundum and Al powder as raw materials by firing at 1450 °C in flowing argon. The effects of binders on phase composition and microstructure evolution were investigated. The results show that the external of specimens with thermosetting phenolic resin and water soluble resin as binders both contained SiC, MgAl 2 O 4 , corundum and Al 4 O 4 C phases. In center of the specimens, Al 4 C 3 and Al 2 OC phases appeared in the thermosetting phenolic resin bonded specimens while Al 4 O 4 C and Al 2 OC phases appeared in the water soluble resin bonded specimens. The microstructure shows that MgAl 2 O 4 whiskers generated at surface of both specimens through gas-gas reaction. As for the specimens with thermosetting phenolic resin as binder, the residual carbon (decomposed from phenolic resin) and Al in the external of the specimen react with O 2 to form CO and Al 2 O, which promoting the formation of plate-like Al 4 O 4 C. In the center of the specimen, Al 4 C 3 , Al 2 O 3 and Mg(g) formed. Mg(g) migrates to outside and transforms to MgAl 2 O 4 whiskers, and a part of Al 4 C 3 transform to columnar Al 2 OC. Al 2 OC whiskers can also be generated through the reaction among Al 2 O, CO and C. Compared with the thermosetting phenolic resin bonded specimens, Al at external of the water soluble resin bonded specimen reacts with O 2 to form Al 2 O 3 , which further transforms to particle Al 4 O 4 C. In the center of water soluble resin bonded specimen, a little Al 4 C 3 formed and can totally transform to Al 4 O 4 C and Al 2 OC. [ABSTRACT FROM AUTHOR]

Palladium-silver (Pd–Ag) alloys are important as an alternative to gold-based alloys. The purpose of this study was to investigate the effect of an argon-arc vacuum pressure casting process on the recasting of the Pd–Ag alloy. The recasting Pd–Ag alloys were compared with conventional horizontal centrifugal (HC) casting to an argon (Ar)-arc vacuum pressure (Ar-arc/VP) casting. The first-generation castings were made from a Pd–Ag alloy purchased from a supplier. Next-generation castings were made from 50 wt% Pd–Ag alloy before casting and 50 wt% from previous castings. This sequence was repeated over three generations to form the 2nd, 3rd and 4th recasting ingots. The ingots were then measured for marginal accuracy, interfacial oxidation, hardness and phase identification. The recasting success rate of recastibility reached 100%. Compared with the HC group, the Ar-arc/VP group had better edge precision, smaller oxide layer thickness and lower hardness. The comparison of X-ray diffraction intensity showed that the relative intensities of Pd and Ag in the first, second and third generations recasting of the Ar-arc/VP group were significantly higher than those of the HC group. Phase analysis showed that the trace elements of indium and tin contents in the Pd–Ag recasting ingots of the Ar-arc/VP group were higher than those of the HC group. The results showed that the casting process used for recasting affected the quality of the Pd–Ag alloy. Therefore, Ar-arc/VP casting process could improve the effect of Pd–Ag recasting and maintain the alloy properties in comparison with HC casting. [ABSTRACT FROM AUTHOR]

The fracture behavior of a melt-infiltration-processed SiC/Si composite, used to mimic the matrices of industrial fiber-reinforced ceramic composites, was examined in different atmospheres and temperatures. Specimens tested in four-point bending at 900 °C in oxygen-gettered argon, dry air, or steam-rich atmospheres exhibited higher average fracture strengths than specimens tested at 25 °C. Higher mean fracture strength values were obtained for specimens tested in dry air or in a steam-rich atmosphere at 900 °C than for specimens tested in high-purity, oxygen-gettered argon at this temperature. The increased fracture strengths obtained in air and in steam-rich atmospheres coincided with increased specimen oxidation and apparent oxide filling and blunting of flaws in these composites. A transition in the location of catastrophic failure, from sites of preexisting damage created by Vickers indentations for tests in argon to other locations for tests in air or steam-rich atmospheres, was also consistent with such apparent oxide filling/blunting of indentation-induced flaws. [ABSTRACT FROM AUTHOR]

The development of a novel small-scale electrical power source technology is essential in the design of microelectronic devices. In this sense, this study presents the optimization of the sputtering deposition parameters to grow a LiFePO 4 cathode, a candidate material for the development of solid-state lithium batteries. Specifically, it was evaluated the effect of argon deposition pressure on the electrochemical properties of LiFePO 4 cathode. By combining X-ray photoelectron spectroscopy with electrochemical characterization methods, it was revealed that argon deposition pressure modulated the degree of the re-sputtering effects. In addition, it was found that high argon deposition pressure leads to the growth of LiFePO 4 films with oxygen and phosphor deficiency. The absence of these atoms caused the decrease in the LiFePO 4 electrochemical activity. Conversely, deposition parameters based on low argon sputtering pressure significantly reduced the degree of the re-sputtering effects, which in turn favored the growth of stoichiometric LiFePO 4 films with an enhanced electrochemical activity. [ABSTRACT FROM AUTHOR]

There exist many ways to calculate the contact angle of a sessile droplet on a planar surface on the basis of molecular modeling data, and the result may depend on the chosen approach. This paper presents molecular dynamics simulations of argon and water sessile droplets on simple model and more complex atomistic substrates. Several approaches for calculating contact angles are described. These approaches are based on an analysis of instantaneous droplet's configurations and averaged density profiles. The latter are analyzed using density cutoffs and the Sobel filters. Parameters of the interaction between the planar surface and the fluid are being tuned in order to consider model lyophilic and lyophobic substrates. Dependences of the contact angle on the strength of interaction between the fluid and the substrate and on the droplet size are obtained. The apparent line tensions for the observed sessile droplets are evaluated. • Contact angles of argon and water sessile droplets on planar surfaces are calculated. • Dependences of contact angle on temperature and droplet size are obtained. • Four different approaches for contact angle calculation are implemented. • The obtained contact angle value may depend on the way of its calculation. • Sign of the apparent line tension is different for argon and water sessile droplets. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrogen removal from particle-reinforced Al composite is critical for preventing porosities near particle clusters and improving comprehensive material properties. This study investigated the effects of different argon flow schemes and power ultrasound on bubble dispersion in water. Based on similarity theory, the optimal argon flow scheme for ultrasonic-assisted argon (UAA) treatment was identified and applied to TiB 2 /2024 Al composite to explore the degassing mechanism. Three argon flow schemes for UAA treatment: EV-EC (External ventilation, equal channel), IV-EC (Internal ventilation, equal channel), and IV-RC (Internal ventilation, reduced channel) were evaluated through numerical simulation and water simulation experiments. The results demonstrated that IV-RC scheme exhibits superior bubble dispersion characteristics and a broader bubbling range. Experimental results in Al composite confirmed that UAA treatment with IV-RC scheme achieved the highest degassing efficiency, with a relative density improvement of up to 98.01 % and the lowest hydrogen content (0.0235 ppm). Synchrotron radiation X-ray computed tomography results indicated that UAA treatment effectively reduces the pore size and volume, transforming interconnected, complex pores into dispersed, nearly spherical ones. Ultrasonic cavitation aids this process by breaking small argon bubbles into numerous tiny bubbles that penetrate deeply into the melt, reducing the wettability angle between particles and the matrix and thereby improving hydrogen removal efficiency. [ABSTRACT FROM AUTHOR]

Liquid argon (LAr), widely used as the active target in neutrino and dark matter experiments, is a scintillator with a light yield of approximately 40 photons/keV. The scintillation spectrum is centered at 128 nm, and the attenuation length is of the order of meters, depending on the purity. The addition of small amounts of dopants allows for shifting the scintillation peak simplifying the light detection and opening the possibility to the development of imaging systems. There is no precise knowledge of the optical properties of LAr in the VUV range, but it could be exploited to improve the performances of liquid argon-based experiments, especially when the involved mass is in the ton scale. LArRI (Liquid Argon Refractive Index) aims to directly measure the refractive index of LAr in the VUV spectrum, using an interferometric technique. The refractive index is obtained by comparing two interference patterns, created in vacuum and liquid, acquired with cryogenic silicon photomultipliers. This work primarily presents the methodology, the preliminary tests, and the analysis strategy, which are intended to be applied to real data shortly. [ABSTRACT FROM AUTHOR]

ALLEGRO is a proposed FCC-ee general-purpose detector concept with a noble liquid (NL) electromagnetic calorimeter (ECAL) as a central feature. Calorimetry based on liquified noble gases is a well-proven technology that has been successfully applied in numerous high-energy physics (HEP) experiments. This technology provides excellent energy resolution, linearity, stability, uniformity and timing properties at a reasonable cost, making it a strong candidate for future HEP experiments. By using multi-layer printed circuit boards as readout electrodes, we can build a calorimeter with almost arbitrarily high granularity. This in turn allows for four-dimensional imaging, machine learning algorithms and particle-flow reconstruction to be fully exploited. In this proceedings contribution we give an overview to the ALLEGRO concept and present the ongoing R&D work for adapting NL calorimetry to an ECAL of a lepton collider experiment. In addition to simulation studies and expected performance, we show results on signal extraction and noise mitigation studies made with readout electrode prototypes and compare the measurements to simulations, as well as discuss test results of absorber prototypes. In addition we present progress of the mechanical design project and status of the barrel ECAL test-beam prototype module development. [ABSTRACT FROM AUTHOR]

Power-over-Fiber (PoF) technology has been used extensively in settings where high voltages require isolation from ground and electromagnetic isolation is critical. In cryogenic environments, PoF offers a reliable power transmission technology, leveraging optical fibers to transfer power with minimal system degradation. PoF technology excels in maintaining low noise levels and isolation when delivering power to sensitive electronic systems operating in extreme temperature ranges and high voltage environments. In a novel application of PoF for a HEP detector, power is provided to photon detector modules located on a surface at ∼ 300 kV with respect to ground in the planned DUNE experiment. This summary paper of the PoF talk at the 16th PISA Meeting on Advanced Detectors highlights the R&D effort of PoF in extreme conditions and underscores its capacity to revolutionize power delivery and management in critical applications offering a dependable solution with low noise, optimal efficiency, and superior isolation. The DUNE (Abi et al., 2020) experiment will soon deploy large liquid argon (LAr) time projection chambers (TPC) to detect neutrino interactions and other particle physics phenomena. In addition to the particle tracking provided by the TPC, photon detectors, powered by a first ever PoF system, in the cryostat will leverage the high scintillation light yield of LAr to provide crucial timing and additional calorimetric information. [ABSTRACT FROM AUTHOR]

The Photon Detection System (PDS) is a crucial component of the ICARUS detector in the Short Baseline Neutrino (SBN) Program at Fermi National Accelerator Laboratory (FNAL). It consists of 360 PhotoMultiplier Tubes (PMTs) 8" Hamamatsu R5912-MOD and, since June 2020, it has been operating at the liquid Argon cryogenic temperature. During these years, the PMTs have shown gain losses as an aging effect. Using a climatic chamber at the INFN Sezione di Catania, we confirmed a stable gain for a single PMT 8" Hamamatsu R5912-MOD when operated at room temperature, and a persistent gain loss at temperatures around -70 °C, although this temperature is rather higher than that of the liquid Argon. [ABSTRACT FROM AUTHOR]

Boron nitride (BN) interphase plays a crucial role in silicon carbide fiber-reinforced silicon carbide (SiC f /SiC) composites, because it directly influences the mechanical properties and high-temperature resistance of SiC f /SiC composites. However, fabricating a high-quality BN interphase on SiC fabrics with low cost and high efficiency remains a significant challenge. In this study, a uniform and dense BN interphase was overally prepared on 2.5D-SiC fabric by precursor-derived method. Whether it is the surface fiber or the inner fiber of the 2.5D-SiC fabric, the interphase thickness remains consistent at 550 ± 30 nm. Moreover, the obtained BN exhibits a lower crystallization temperature (approximately 1200 °C). Additionally, it maintains a strong bond with the fabric after high-temperature treatment at 1600 °C in an argon atmosphere and also retains robust adhesion after high-temperature vacuum treatment at 1600 °C. This study not only presents the overall fabrication of a uniform BN interphase on SiC fabric but also provides a novel strategy for preparing interphases on various types of fabrics. • A dense and uniform BN interphase is overall prepared by precursor-derived method for the first time. • A lower crystallization temperature of the BN precursor (∼1200 °C) is exhibited. • The BN interphase thickness of the inner and surface fibers of the fabric is 550 ± 30 nm. • At 1600 oC in Ar atmosphere, the BN interphase effectively inhibits SiC grain growth. [ABSTRACT FROM AUTHOR]

The results of studies of magnetron sputtering of copper at discharge currents from 2 to 15 A in a 76 mm diameter planar magnetron are presented. In addition to the standard gas mode at an argon pressure of 0.12 Pa, a gasless mode was also implemented in which no argon was supplied to the vacuum chamber and the base pressure was 1·10−3 Pa. The stable gasless mode is realized at a discharge current higher than 8 A. The electrical discharge parameters as well as the copper sputtering rate, the ion current density on the substrate and the degree of ionization of the sputtered target material were measured and compared for the two modes mentioned. The plasma composition was also measured by optical spectrometry. The experimental data were used to calculate the density and composition of the neutral and ion fluxes to the substrate. It is shown that the gasless mode provides a higher ion current density on the probe and a higher degree of ionization of the sputtered copper compared to the gas mode at the same discharge current. The degree of ionization of the sputtered material reaches 14–15 % in gasless mode, whereas in gas mode it varies from 2 to 13 % depending on the discharge current. • Ionization of copper in gasless mode of high-power magnetron sputtering is studied. • Sputtering rate and ion current density on substrate in gasless mode are measured. • Density and composition of the neutral and ion fluxes to substrate are determined. [ABSTRACT FROM AUTHOR]

• The nano-bubbles aggregation in Argon two-phase systems on a Pt substrate have been investigated. • The growth rate of the individual bubbles can be effectively modified with the number or distances of the heat sources. • Whatever the gap between two adjacent heats are smaller, the size, lifespan and stability of the bubbles has increased. • As soon as the existence of a film layer of vapor molecules between two neighboring bubbles, bubbles aggregation phenomena occur. • The spacing between two adjacent heats related to neighboring bubbles aggregation or separation is represented. These days, understanding the nano-bubble aggregation has attracted lot of attentions in various fields from medicine to industries. In the present work, by means of molecular dynamics simulation, effects of surface conditions on nano-bubbles aggregation in two-phase systems have been studied. Hence, in the argon two-phase system, two heat sources have been installed on a Pt substrate and their distance has been changed: From the first to seventh system, the gap between these two surface-mounted heat sources is 46.80, 39.90, 31.20, 24.30, 23.40, 11.70, and 00.00 Å, respectively. Corresponding to the simulation results, the effect of the number of heat sources and their distances on the individual-bubbles growth rate is quite evident: whatever the spacing between two adjacent heats are smaller, the formed nano-bubbles are more stable or larger as well, and have longer lifespan. Besides, according to the calculation of the changes in quantities of the bubble contact angle (CA/deg.), size (H/Å), diameter of the cross-section area (L/Å), and thickness of the outer layer (A/Å), it was observed that each of these nano-bubbles, which have the same formation conditions and exist simultaneously in the equilibrium system, behave differently. Interestingly, by reducing the distance between the two sources in the range of 31.20–11.70 Å, owing to the existence of a film layer of vapor molecules between two neighboring nano-bubbles, the bubbles aggregation phenomena occur. At last, if the gap between the heat two sources becomes zero, an ultra-stable nano-bubble, which will has the largest size, lifetime and stability, is observed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ar, C, and Fe low energy and low fluence Ion implantation for 2DEG electrical isolation. • Defects creation by ion implantation in AlGaN/GaN heterostructure. • 2DEG AlGaN/GaN high electron mobility transistor (HEMT). • Non-radiative recombination centers produced by Ion bombardment. • High thermal stability of 2DEG isolation by ion implantation. • Defects diffusion towards AlGaN surface. We report a comparative study of the isolation mechanisms of two-dimensional electron gas (2-DEG) in Al 0.2 Ga 0.8 N/GaN heterostructure by room temperature ion implantation with Ar, C or Fe at 15, 20, 18 keV and fluences of 7 × 1013, 1 × 1014, 5 × 1013 cm−2, respectively. The samples were annealed up to 900 °C post-implantation and characterized by X-ray Diffraction, X-ray Photoelectron Spectroscopy, Photoluminescence, Rutherford Backscattering Spectrometry in Channeling mode and Capacitance Voltage profiling. The ion implantation produces unrecoverable crystal lattice damage such as point defects and non-radiative carrier traps level into the band gap of GaN. As a consequence, a decrease in the number of occupied states at the upper side of the valence band of GaN was observed. Moreover, defects accumulation at the near-surface region by annealing at 900 °C was observed. Due to the various defects, the concentration of 2-DEG carriers, after ion implantation, for all three ions investigated, is reduced from 1019-1020 to less than 1013 ––1014 cm−3. The 2-DEG isolation was stable up to 900 °C for all three ions, while the non-radiative defects and carrier traps produced were slightly more stable in the case of Fe implantation. The reduction of carrier concentration is responsible for the isolation of 2-DEG. [ABSTRACT FROM AUTHOR]

The paper compares the collective acceleration of ions in a Luce diode in residual atmospheres of air, argon and krypton at pressures of 6–156 mPa, evaluating the efficiency of capture of Ar and Kr ions into collective acceleration from their residual atmospheres. At a diode voltage of ∼232 kV, proton energies were 510 ± 38, 619 ± 62 and 567 ± 59 keV for air, argon, and krypton atmospheres, respectively, while the number of protons per shot was approximately 2 and 3 times higher in the argon and krypton residual atmosphere compared to the normal residual atmosphere. This increase in energy also led to a significant increase in the proportion of protons with energies greater than 3.02 MeV - to 1010 per shot on average. It was found that with increasing argon pressure, the diode current noticeably decreases, and with increasing krypton pressure, on the contrary, the diode current noticeably increases, which can be explained by the fact that argon is more neutral than krypton. The efficiency of capture of Ar and Kr ions into collective acceleration from their residual atmospheres was estimated as 0.06 % and 0.19 %, respectively. • Residual atmospheres of air, Ar and Kr are compared at pressures of 6–156 mPa. • Protons are accelerated to higher numbers and energies in Ar and Kr atmospheres. • Diode current increases with increasing Kr pressure due to its electronegativity. • On average, there are 3 times more accelerated Kr ions per shot than Ar ions. [ABSTRACT FROM AUTHOR]

We developed a system to measure changes in PMT photocathode's behavior from room to cryogenic temperatures and to determine the absolute quantum efficiency (Q.E.) by comparing the photocathode current with that of a calibrated photodiode. Preliminary test results on the 8-inch Hamamatsu R5912-MOD PMT coated with ≈ 200 μ g/cm2 of tetraphenyl butadiene do not show significant variations in Q.E. at cryogenic temperatures with respect to room temperature and are in agreement with other measurements. [ABSTRACT FROM AUTHOR]

The Power over Fiber (PoF) technology delivers electrical power by sending laser light through an optical fiber to a photovoltaic power converter, in order to power sensors or electrical devices. This solution offers several advantages: removal of noise induced by power lines, robustness in a hostile environment, spark free operation when electric fields are present and no interference with electromagnetic fields. This technology is at the basis of the Cryo-PoF project: an R&D funded by the Italian Institute for Nuclear Research (INFN) in Milano-Bicocca (Italy). This project is inspired by the needs of the DUNE Vertical Drift detector, where the VUV light of liquid argon must be collected at the cathode, i.e. on a surface whose voltage exceeds 300 kV. We developed a cryogenic system, which is solely based on optoelectronic devices and a single laser input line, to power both the Photon Detection devices and its electronic amplifier. The Milano-Bicocca setup employ a commercial GaAs laser source with 2 W maximum power and a photovoltaic power converter with efficiency of ∼ 30% at liquid nitrogen temperature. The results obtained in Milano Bicocca will be presented with emphasis on performance and potential application in the field of applied physics. [ABSTRACT FROM AUTHOR]

The Deep Underground Neutrino Experiment (DUNE) has among its primary goals the determination of the neutrino mass ordering and the possible CP-violating phase in the neutrino mixing matrix. The System for On-Axis Neutrino Detection (SAND) is one of the three components of the DUNE Near Detector complex, permanently located on-axis to monitor the neutrino beam stability and measure its flux. SAND includes a novel liquid Argon detector - GRAIN - designed to image neutrino interactions using scintillation light produced in Ar by charged particles, eliminating the dependence on slow charge collection of LAr TPCs. Two optical systems are currently being developed for GRAIN, both based on Silicon Photomultiplier (SiPM) matrices, coupled either to UV cryogenic lenses or Coded Aperture masks. This contribution will present the design of GRAIN optical systems and their spatial resolution performance in preliminary simulation studies. [ABSTRACT FROM AUTHOR]

DarkSide-20k is a 50 t dual phase liquid argon time projection chamber currently under construction in Hall-C of LNGS. DarkSide-20k is projected to lead the search for WIMP like dark matter, probing down to WIMP-nucleon cross sections of 10−48 cm2 for a WIMP mass of 0.1 TeV. In order to achieve this goal DarkSide-20k employs novel techniques and technologies including: the use of underground argon depleted in the radioisotope 39Ar; a neutron veto integrated into the TPC mechanical structure; large-area cryogenic SiPM array photodetectors. These bespoke SiPMs, assembled into photodetector modules, instrument both the veto and TPC detectors. The design and ongoing production of these photodetector modules will be reported. [ABSTRACT FROM AUTHOR]

[Display omitted] • Propranolol was completely degraded by nonthermal plasma in three feed gases. • In Ar/O 2 atmosphere the lowest specific energy density was achieved – 75 kJ/dm3. • H 2 O 2 was the predominant reactive oxygen species in Ar plasma. • Hydroxyl radical had no effect on degradation in Ar/O 2 mixture. • The abundance of degradation products was theoretically supported. Propranolol, a beta-blocker, is a widely used drug for cardiovascular diseases. A synthetic sample containing propranolol (PRO) solution at native pH was recirculated up to ten times through an original coaxial non-thermal plasma reactor with a water falling film. Different discharge conditions, feed gasses, and power greatly influenced the extent of PRO degradation and the abundance of degradation products. The highest degradation rates were achieved in Ar plasma, either pure or in a mixture with O 2 , with over 70% of PRO degraded after only two passes through the DBD reactor. The full non-thermal plasma treatment was followed by a minimal change of pH value and conductivity. On the other hand, ambient air as the feed gas resulted in 60% of PRO degradation rate after the full treatment and contributed to a major drop in pH value and an increase in the conductivity of the treated solution. The structures of 47 degradation products in all three gases were identified and the degradation pathway is proposed, supported by DFT methodology. Scavenging experiments demonstrated that hydroxyl radical was predominant when plasma was generated using ambient air and Ar, while it had a minimal effect on the degradation in the mixture of Ar and O 2. The desired level of propranolol decomposition was achieved only by the adjustment of the nonchemical parameters of the treatment, such as plasma gas composition and power. These results imply that a non-thermal plasma reactor is a highly effective method for pharmaceutical wastewater treatment, with no catalysts added. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultra-small PtSn clusters were controlled through argon calcination atmosphere. • More than 8 g[C 3 H 6 ]·g[Pt]−1·h−1 of propylene formation rates were achieved. • Ultra-low deactivation constant of 0.0001 h−1 was evaluated for PtSn8@S-1-Ar-50. • The anticipating C 3 H 6 selectivity was owing to PtSn@S-1 confined-catalysis. It's a great challenge for enhancing the stability over Pt-based catalysts with low Pt loading during propane dehydrogenation based upon the manipulation of ultra-small PtSn clusters and their compositions. Here, we developed a novel strategy to produce and stabilize sub-nanometer PtSn clusters even atomical dispersion within Silicalite-1 crystals via tailoring calcination atmosphere from air to argon, which could achieve a stable performance of propane dehydrogenation with only 0.15 wt% Pt loading. Argon calcination atmosphere of PtSn@Silicalite-1 significantly decreased the size of PtSn clusters, which further presented a strikingly catalytic performance with the high formation of propylene over 8.0 mol[C 3 H 6 ]·g[Pt]−1·h−1 even after 3840 min at 600 °C (WHSV=760 g[C 3 H 8 ]·g[Pt]−1·h−1). Hardly any deactivation was obtained over PtSn8@S-1-Ar-50 after long-term runs for 3840 min with an extremely low deactivation constant of 0.0001 h−1 so far, which was mainly derived from the outstanding stability of PtSn sub-nanometers within S-1 crystals through appropriate flow rate of argon calcination atmosphere. [ABSTRACT FROM AUTHOR]

It is important to improve thermal efficiency and to reduce harmful exhaust gas emissions in internal combustion engines. A closed cycle engine system that uses a monatomic molecular gas as the working fluid can be expected to have high thermal efficiency due to the high specific heat ratio of the gas. Several studies have been reported on closed cycle engines with conventional spark ignition or compression ignition. This research newly proposes an argon circulated closed cycle homogeneous charge compression ignition (HCCI) engine system fueled with hydrogen. In this engine system, effects of in-cylinder gas initial temperature and residual water in recirculated gas on combustion characteristics were investigated. The results show that the system with argon circulation has the wider range of operable conditions and the higher thermal efficiency compared to the case with air as the working fluid. • An argon circulated closed cycle homogeneous charge compression ignition engine fueled with hydrogen was proposed. • The HCCI combustion of hydrogen is possible by the argon circulation under a wide range of operating conditions in this study. • The third body effects of argon and residual water in the intake mixture have some effects to delay the combustion. [ABSTRACT FROM AUTHOR]

• We proposed a SiC deposition method by ion beam induced chemical vapor deposition (IBICVD). • We selected Ar+ ions as an ion beam for IBICVD. • We used dimethylsilane (DMS) as a source gas for IBICVD. • SiC film was formed when substrates were irradiated by Ar+ ions in conjunction with DMS. In this paper, a methodology for silicon carbide (SiC) film formation by ion beam induced chemical vapor deposition (IBICVD) using dimethylsilane (DMS) is presented. Both pure DMS gas and Ar+ ion beam were simultaneously injected to a Si substrate. The Ar+ ion energy was 100 eV. The Si substrate temperature was 400, 600, or 800 °C. The duration of each ion beam injection experiment was 10 h. When the substrate temperature was 400 °C, no film formation occurred by the IBICVD experiment. In the case of 600 °C, a film was found to be formed on the substrate by the injection of both DMS gas and Ar+ ion beam. Although Fourier transform infrared (FTIR) spectroscopy measurement of the film showed that the film consisted of SiC, the film thickness was not enough to analyze the film characteristics further. When the Si substrate was set at 800 °C, a film was formed on the substrate by IBICVD. FTIR, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS) measurements of the film showed the occurrence of SiC deposition. The XPS measurement also showed that the atomic concentration ratio of carbon to silicon (C/Si ratio) of the film was 1.36. Therefore, excessive C atoms were incorporated to the deposited films. On the contrary, the C/Si ratio of a SiC film prepared by the thermal CVD method using DMS was 1.88. These results suggest that the Ar+ ion beam induced chemical vapor deposition using DMS is useful for reducing of the amount of C atoms to be excessively included in the film. [ABSTRACT FROM AUTHOR]

Methods of preparation and application of zinc oxide nanoparticles doped with Mn(II) and Co(II) ions are presented and discussed in the paper. Part one shows the results of the solvothermal synthesis of zinc oxide nanoparticles doped with Mn(II) and Co(II) ions. The effect of process parameters on the properties of doped nano zinc oxide has been identified. We also examined the impact of annealing in argon atmosphere of doped zinc oxide nanoparticles on physicochemical properties. Morphology analysis was performed using scanning microscopy and molecular analysis was performed using by inductively coupled plasma - optical emission spectrometry. The zeta potential was measured for samples annealed in argon atmosphere and for samples not annealed. Phase analysis was performed by x-ray diffraction. Based on this analysis, the lattice parameters were determined. [ABSTRACT FROM AUTHOR]

A novel metal-free amperometric sensor based on O 2 /Ar plasma modified carbon nanowalls (CNW) was successfully developed for non-enzymatic detection of hydrogen peroxide (H 2 O 2). This study demonstrates the effectiveness of surface modification of CNW by O 2 /Ar plasma treatment to improve the electrochemical sensing performance. It was shown that the CNW treated in low oxygen flow rate (O 2 /Ar: 0.1/10sccm) exhibited the highest concentration of incorporated oxygen on its structure, which consequently resulted in conversion of intrinsic hydrophobicity of CNW to hydrophilicity. Interestingly, however, further increase in oxygen flow rate did not increase the oxygen content of CNW structure, but instead it resulted in an increment in the defect and contributing less oxygen on CNW surface. The highest amperometric response was observed for the CNW treated with O 2 /Ar: 1.0/10sccm, which has lower oxygen content than the CNW treated with O 2 /Ar: 0.1/10sccm, but still possessing hydrophilic characteristic as well as owning more defect sites. These results can suggest the importance of both defects and oxygen-containing functional groups in electrochemical behavior of the electrode as both defects and oxygen-containing functional groups can act as potential active sites for electrochemical reactions and oxygen-containing functional groups can enhance the hydrophilicity and surface area wetted by the electrolyte. The modified CNW exhibited the potential for quantification analysis of H 2 O 2 with a wide linear range covering from 50 μM to 28000 μM, a good sensitivity of 126.6 μA/mM.cm2 and a detection limit of 0.91 μM (S/N = 3). This study demonstrates the success in utilizing the CNW structure towards detecting of H 2 O 2 as a metal-free sensor. [Display omitted] [ABSTRACT FROM AUTHOR]

Noble gas isotope systematics of ocean island basalts (OIB) provide evidence for relatively undegassed and primitive mantle sources. These OIB sources partly derive from the deep mantle by virtue of their distinctiveness from mid-ocean ridge basalts (MORB), which dominantly sample upper mantle. New helium, neon and argon isotope data are presented for Canary Islands lavas, carbonatites and cumulate and mantle xenoliths confirming 3He/4He ratios that are the same or lower than MORB, but that are heterogeneous (∼3–9.5R A) within and between islands in the archipelago. Neon and Ar isotope systematics for lavas are mostly within the range of air compositions. Harzburgite xenoliths from Lanzarote, which are interpreted to represent ancient refractory mantle residues, have distinct He-Ne-Ar isotope systematics from lavas or cumulate xenoliths. The harzburgites are characterized by forsteritic olivine (>Fo 91) with uniformly low-3He/4He (6.6 ± 0.2R A), high 40Ar/36Ar (630–4900), and have Ne isotope compositions that range between air values or that are similar or more nucleogenic than depleted MORB mantle (DMM). Similar refractory mantle peridotites have been discovered as xenoliths at other OIB localities and are likely to be distinct from continental lithospheric mantle. Refractory mantle (RM), which by virtue of its high melting temperature is difficult to partially melt, may be a significant component in the convecting mantle and has potential to impart a cryptic noble gas signature to partial melts in intraplate, divergent and convergent margin settings. In this sense, RM may represent a 'sixth mantle component' after DMM, high-µ (high 238U/204Pb; HIMU), enriched mantle endmembers (EMI, EMII) and the 'focus zone' (FOZO). An RM-type component may be presented in the older eastern Canary Islands and possibly in recent rejuvenated volcanism from Teide (Tenerife). Canary Island intraplate volcanism samples multiple mantle components, confirming that the most gas-rich mantle sources involved in magmatism dominate OIB noble gas compositions. [ABSTRACT FROM AUTHOR]

High-purity argon is conventionally recovered from air by cryogenic distillation, which is a mature, efficient but high-cost technology. In recent years, membrane gas separation technology is starting to emerge illustrating the potential to achieve lower production costs compared to distillation, without compromising the final product quality. In this work, a flowsheet of a conventional cryogenic distillation system for the separation of an oxygen-argon mixture was built and simulated in the gPROMS™ modeling environment. Then, a detailed mathematic modeling framework of a hollow fiber membrane system for the same separation was developed. The predictive power of the model is in a good agreement with theoretically expected results for a wide range of operating conditions. The results indicate that commercially available polymeric membranes are not capable of achieving a high-purity argon product while innovative materials, such as carbon membranes, turn out to be more efficient. Finally, the performance of the membrane process was compared with the cryogenic distillation process using an optimization-based techno-economic analysis. The comparison revealed that the distillation process has a lower operational cost compared to a membrane process for a final product purity of 99.9 mol%. • Membranes Modeling Framework for Argon separation. • Cryogenic Distillation Flowsheet for Argon separation. • Optimization of the above processes. • Techno-economic analysis and comparison of the above processes. • Cryogenic distillation leads to lower operating costs. [ABSTRACT FROM AUTHOR]

Background: The noble gases argon and xenon are potential novel neuroprotective treatments for acquired brain injuries. Xenon has already undergone early-stage clinical trials in the treatment of ischaemic brain injuries, with mixed results. Argon has yet to progress to clinical trials as a treatment for brain injury. Here, we aim to synthesise the results of preclinical studies evaluating argon and xenon as neuroprotective therapies for brain injuries.Methods: After a systematic review of the MEDLINE and Embase databases, we carried out a pairwise and stratified meta-analysis. Heterogeneity was examined by subgroup analysis, funnel plot asymmetry, and Egger's regression.Results: A total of 32 studies were identified, 14 for argon and 18 for xenon, involving measurements from 1384 animals, including murine, rat, and porcine models. Brain injury models included ischaemic brain injury after cardiac arrest (CA), neurological injury after cardiopulmonary bypass (CPB), traumatic brain injury (TBI), and ischaemic stroke. Both argon and xenon had significant (P<0.001), positive neuroprotective effect sizes. The overall effect size for argon (CA, TBI, stroke) was 18.1% (95% confidence interval [CI], 8.1-28.1%), and for xenon (CA, TBI, stroke) was 34.1% (95% CI, 24.7-43.6%). Including the CPB model, only present for xenon, the xenon effect size (CPB, CA, TBI, stroke) was 27.4% (95% CI, 11.5-43.3%). Xenon, both with and without the CPB model, was significantly (P<0.001) more protective than argon.Conclusions: These findings provide evidence to support the use of xenon and argon as neuroprotective treatments for acquired brain injuries. Current evidence suggests that xenon is more efficacious than argon overall. [ABSTRACT FROM AUTHOR]

Novel analytical approaches to determining the trapped 38Ar/36Ar ratio of gases contained within Martian meteorites are presented and applied to the Martian regolith breccia Northwest Africa (NWA) 7034 and paired stone NWA 11220. The resulting data indicate that extensive mass-dependent fractionation of atmospheric Ar may have occurred within 150 million years of planetary formation, ostensibly as a result of diffusion-limited hydrodynamic escape. The inferred fractional loss of Ar and lighter atmospheric constituents exceeds 50%. These data suggest that volatiles derived from planetary outgassing and/or impactors may dominate the present abundance of atmospheric Ar. [ABSTRACT FROM AUTHOR]

We began this work intending to illustrate the network origins of jargon, a signal feature of team learning and the division of labor. In the process, we came to recognize the substantive importance of message timing, which we discuss as the pulse of a network. This paper describes our route to that recognition. We analyze data from a renovated classic network experiment providing empirical support for three hypotheses. The first, and most familiar from past work, is that teams moving down their learning curve to greater efficiency are prone to shared jargon. As a team moves down its learning curve, language drifts away from day-to-day speech, into jargon. The second and third hypotheses concern network correlates of the drift. With respect to network structure, teams are less likely to converge on jargon when communication is concentrated in one teammate. With respect to pulse, teams are more likely to converge on jargon when communication efforts are numerous and crowded in time. The two network predictors overlap conceptually. They both involve learning and access to information, but are distinct in their mechanism: Structure provides access. Pulse creates motivation to access. Teammates keeping up with numerous messages concentrated in time have a shared incentive to find shorthand terms (i.e., jargon) that enable faster exchange of accurate information. Network structure predicts team convergence on jargon, but pulse is a stronger predictor. Directions for new research are discussed. • Teams converge on jargon as they go down their learning curve. • Network mechanisms: structure provides access, pulse creates an incentive to access. • Network pulse is more important than structure for team convergence on jargon. [ABSTRACT FROM AUTHOR]

• The argon-nitrogen mixture was used as shielding gas to weld 316LN austenitic stainless steel and the magnetic permeability of welded joint is significantly lower than 1.03. • Using argon-nitrogen mixed gas as shielding gas, the mechanical strength and toughness of welding joint at cryogenic temperature can be effectively improved. • The microstructure of the welded joints using different ratios of argon-nitrogen mixed shielding gases was analyzed by electron backscatter diffraction. To ensure the stable operation of fusion reactors and synchrotron radiation facilities, the magnetic permeability of the weld joints in 316LN austenitic stainless steel (ASS) must be μ r ≤ 1.03. Therefore, controlling magnetic permeability during welding is essential. This paper examines the impact of nitrogen in the shielding gas on the magnetic permeability, microstructure, and mechanical properties of 316LN welded joints. This was achieved by using argon-nitrogen mixed shielding gas to weld the test plates. The findings indicate that the primary microstructures of the welded joints consist of austenite and a small amount of ferrite. The magnetic permeabilities are measured at 1.026, 1.015, 1.010, 1.007, 1.004, and 1.005, respectively. The main factor contributing to the decline in magnetic permeability with increased nitrogen content in the shielding gas is the reduction in ferrite content. Additionally, adding nitrogen to the shielding gas improves the mechanical properties of the welded joints at 4.2 K. The ultimate tensile strengths of the welded samples using pure argon gas and argon-nitrogen mixed gas (1 % and 2 % nitrogen) were 1423.73 MPa, 1465.49 MPa, and 1546.45 MPa, respectively. The impact energy of the samples was 38 J , 139 J , and 137 J , respectively. Analysis of the fracture surfaces reveals that the argon-nitrogen mixed gas welded samples exhibit ductile fracture with dimples and micropore morphology. In contrast, the pure argon gas welded samples show the combination of ductile and brittle fracture. It is proposed that fine grain strengthening and the dispersion strengthening effect of N is the main factors in improving strength. This study provides an effective guide for the application of the welded joint of 316LN ASS at cryogenic temperature. [ABSTRACT FROM AUTHOR]

The effect of Ar content in the range of 0–100 % was studied separately in the outer, intermediate and nebulizer gas flow on the excitation temperature and electron density, the intensity of element lines and the molecular background in a N 2 microwave induced plasma. The addition of Ar to the nebulizer flow leads to an increase in the intensities of both atomic and ionic lines with total excitation energies (E sum) 3–13 eV to 1.7 times, depending on the selected line. Addition to the outer or intermediate flow shifts the atomic-ionic equilibrium towards the formation of ions. As a result, the intensity of ionic lines (E sum = 10–13 eV) increases up to 1.2 times, the decrease in the intensity of atomic lines (E sum = 3–6 eV) reaches up to 20 %. The excitation temperature and electron density in the plasma did not change significantly regardless of which flow the argon was fed into. The intensity of the molecular components of the plasma background (OH, NH, NO) changes significantly when Ar is introduced into the nebulizer flow. The OH intensity increases to 1.8 times, and NH intensity increases to 1.5 times at 100 % Ar relative to pure N 2 plasma. Supplying 100 % Ar simultaneously into the intermediate and nebulizer gas flow and N 2 into the outer flow allows one to reduce the limits of detection by up to 3.3 times, depending on the selected spectral line of the element. [Display omitted] • The effect of argon in the outer, intermediate or nebulizer gas flow on the parameters of the nitrogen MIP-OES is presented. • An increase in line intensities is observed when argon is supplied to the nebulizer gas flow. • Addition of argon in the intermediate and nebulizer gas flow reduces MIP-OES detection limits by up to 3.3 times. [ABSTRACT FROM AUTHOR]