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The hydriding/dehydriding characteristics of 90 wt% MgH2a10 wt% MeSi2 (Me = Ti, Cr) composites, synthesized by ball milling under argon, were studied by Sievertas type apparatus and by high-pressure differential scanning calorimetry (HPDSC). The composites have demonstrated similar absorption kinetics and capacity at temperature of 300 degree C and a pressure of 1 MPa. They showed fast kinetics and achieved absorption capacity higher than 6 wt%. Slightly higher values for the enthalpy of hydriding and dehydriding were obtained at scanning conditions in the HPDSC for the composite 90 wt% MgH2a10 wt% CrSi2 compared to those for the composite with addition of TiSi2.

Li sub(0.33)La sub(0.55)TiO sub(3) solid electrolytes with a pure phase were synthesized by the citric acid-supported sol-gel method and then sintered under controlled redox atmospheres of air, argon and hydrogen. Although of similar morphology and relative density, Li sub(0.33)La sub(0.55)TiO sub(3) samples sintered under reduction atmosphere such as argon and hydrogen exhibited a tetragonal structure with lattice distortion. The distortion and volume expansion of the crystal lattice was identified as originating from the transformation of the Ti valence state, and this was more clearly observed under sintering of the hydrogen atmosphere. The qualitative analysis of the Ti valence state using an X-ray Photoelectron Spectroscopy experiment was performed and indicated that the largest amount of Ti super(3+)(18.6%) was formed in the Li sub(0.33)La sub(0.55)TiO sub(3) samples sintered under hydrogen atmosphere. The relationship between the lattice distortion and the lithium ion conductivity of the Li sub(0.33)La sub(0.55)TiO sub(3) sintered under different atmospheres is also discussed on the basis of the lattice distortion.

A new compound Er sub(3)Co sub(4)Al sub(12 ) was prepared by arc melting under argon atmosphere. The powder X-ray diffraction data of Er sub(3)Co sub(4)Al sub(12 ) were successfully indexed, giving a hexagonal structure with a = 8.6185(2) Aa, c = 9.2347(3) Aa, and unit-cell volume V = 594.04 Aa super(3). Compound Er sub(3)Co sub(4)Al sub(12 ) has the Gd sub(3)Ru sub(4)Al sub(12 ) type-structure, Z = 2 and space group P6 sub(3)/mmc.

Background A rapid, cost-effective, and eco-friendly method was investigated to enhance the germination potential of lemon basil ( Ocimum africanum Lour.) seeds using radiofrequency (RF) cold plasma treatment, addressing poor germination due to seed dormancy in the CIM-Jyoti variety. Methods Lemon basil seeds (variety CIM-Jyoti) were treated with RF cold plasma using Oxygen (O 2 ), Argon (Ar), and Ar + O 2 gas combinations, varying RF power (W1: 60 W, W2: 150 W, W3: 240 W), process pressure (P1: 0.2 mbar, P2: 0.4 mbar, P3: 0.6 mbar), and treatment time (T1: 5 min, T2: 10 min, T3: 15 min). Germination percentage, seedling vigor indices (SVI-I and SVI-II), and water absorption efficiency were evaluated, with seed surface morphology analyzed via scanning electron microscopy (SEM). Results The Ar + O 2 gas combination at P2W3T2 treatment resulted the highest percent improvements in germination, SVI-I, and SVI-II by 24.5%, 44.0%, and 69.4%, respectively over control and that highest water absorption efficiency after 10 h of soaking and SEM analysis confirmed this was due to surface etching. O 2 gas treatment at P1W2T2 increased germination by 16.3%, SVI-I by 24.3%, and SVI-II by 24.7% compared to the control. Ar gas treatment at P1W2T1 improved germination by 13.3%, with SVI-I and SVI-II enhanced by 29.6% and 23.0%, respectively at P1W2T2. Conclusions RF cold plasma treatment with the Ar + O 2 gas combination proved most effective for enhancing lemon basil seed germination and vigor than using these gases all alone, offering a sustainable alternative for improving seed performance.

This paper reports an XPS surface study of pure phase BiFeO3 thin film produced and later etched by pure argon ions. Analysis of high-resolution spectra from Fe 2p, Bi 4f and 5d, O 1s, and the valence band, exhibited mainly Fe3+ and Bi3+ components, but also reveal Fe2+. High-energy argon etching induces the growth of Fe(0) and Bi(0) and an increment of Fe2+, as expected. The BiFeO3 semiconductor character is preserved despite the oxygen loss, an interesting aspect for the study of the photovoltaic effect through oxygen vacancies in some ceramic films. The metal-oxygen bonds in O 1s spectra are related only to one binding energy contrary to the split from bismuth and iron reported in other works. All these data evidence that the low-pressure argon atmosphere is proved to be efficient to produce pure phase BiFeO3, even after argon etching.

The history of Mars’ atmosphere is important for understanding the geological evolution and potential habitability of the planet. We determine the amount of gas lost to space through time using measurements of the upper-atmospheric structure made by the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. We derive the structure of 38Ar/36Ar between the homopause and exobase altitudes. Fractionation of argon occurs as a result of loss of gas to space by pickup-ion sputtering, which preferentially removes the lighter atom. The measurements require that 66% of the atmospheric argon has been lost to space. Thus, a large fraction of Mars’ atmospheric gas has been lost to space, contributing to the transition in climate from an early, warm, wet environment to today’s cold, dry atmosphere.

Investigations of the surface physicochemical properties of polylactic acid and polylactic acid/hydroxyapatite composite in a 70/30 ratio modified by atmospheric pressure low-temperature glow discharge argon plasma with the pulse duration of 1 μs and 5 μs and repetition rate of 100 kHz are described. Plasma modification of such materials may significantly affect physicochemical properties of surface. The polymerization of l-lactide was carried out at a temperature of 155 °C for 6 h. X-ray diffraction analysis shows that the degree of crystallinity of polylactic acid and composites based on polylactic acid/hydroxyapatite composite increases after plasma treatment due to polymer chain disruption. Infrared spectroscopy indicates that the –C=O absorption band intensity increases with plasma pulse duration, in turn indicating oxidation processes occurring in the polylactic acid surface layers. The wettability characteristics of the materials are improved by the plasma treatment, resulting in decreased water, glycerol, and ethylene glycol contact angle, and enhanced free surface energy.

We report a significant reduction in taper transmission loss by processing ZBLAN fibre under a controlled argon environment. The contrast between tapers processed under argon and ambient air is highlighted through quantitative loss measurement as well as by investigating the surface morphology of the tapers using optical and electron microscopy.

Different applications require different customizations of silicon photomultiplier (SiPM) technology. We present a review on the latest SiPM technologies developed at Fondazione Bruno Kessler (FBK, Trento), characterized by a peak detection efficiency in the near-UV and customized according to the needs of different applications. Original near-UV sensitive, high-density SiPMs (NUV-HD), optimized for Positron Emission Tomography (PET) application, feature peak photon detection efficiency (PDE) of 63% at 420 nm with a 35 um cell size and a dark count rate (DCR) of 100 kHz/mm2. Correlated noise probability is around 25% at a PDE of 50% at 420 nm. It provides a coincidence resolving time (CRT) of 100 ps FWHM (full width at half maximum) in the detection of 511 keV photons, when used for the readout of LYSO(Ce) scintillator (Cerium-doped lutetium-yttrium oxyorthosilicate) and down to 75 ps FWHM with LSO(Ce:Ca) scintillator (Cerium and Calcium-doped lutetium oxyorthosilicate). Starting from this technology, we developed three variants, optimized according to different sets of specifications. NUV-HD–LowCT features a 60% reduction of direct crosstalk probability, for applications such as Cherenkov telescope array (CTA). NUV-HD–Cryo was optimized for cryogenic operation and for large photosensitive areas. The reference application, in this case, is the readout of liquid, noble-gases scintillators, such as liquid Argon. Measurements at 77 K showed a remarkably low value of the DCR of a few mHz/mm2. Finally, vacuum-UV (VUV)-HD features an increased sensitivity to VUV light, aiming at direct detection of photons below 200 nm. PDE in excess of 20% at 175 nm was measured in liquid Xenon. In the paper, we discuss the specifications on the SiPM related to different types of applications, the SiPM design challenges and process optimizations, and the results from the experimental characterization of the different, NUV-sensitive technologies developed at FBK.

Background A significant proportion of patients with pneumothorax who do not tolerate surgery develop intractable pneumothorax after prolonged failure of conservative treatment. This significantly lengthens the duration of hospitalization and patients’ quality of life. As the application of medical thoracoscopy (MT) in the management of pleural diseases is explored, MT combined with argon plasma coagulation (APC) may be an alternative option for the treatment of intractable pneumothorax. Methods A retrospective analysis was conducted on thirteen patients with intractable pneumothorax whose duration of the air leak exceeded seven days and subsequently treated with MT combined with APC at West China Hospital of Sichuan University. Under MT, we first dissected the pleural adhesions with an electrocautery knife, probed for the rupture located in the pulmonary bullae or pleural and cauterised it with APC. Subsequently, all pulmonary bullae were cauterised and human fibrin sealant was sprayed locally on the cauterised surface. Preoperative, intraoperative, and more than one year of postoperative follow-up information was collected from these patients. We divided the patients into two groups with and without detected ruptures treated under MT to compare the overall efficacy and safety of this treatment. Results All patients had pulmonary comorbidities and the median duration of the current pneumothorax episode before MT treatment was 30 days. Nine patients had a history of recurrent pneumothorax episodes, two of whom had been treated with video-assisted thoracoscopic surgery (VATS). Regarding efficacy, the overall median time of time to air leak cessation was 2.5 days, with 2 days in the group with detected ruptures treated and 5 days in the group without detected ruptures treated, and the overall median time of time to chest tube removal was 6 days, with 4 days in the group with detected ruptures treated and 7 days in the group without detected ruptures treated. Regarding safety, only 2 patients experienced postoperative adverse events of fever and chest pain. Conclusions For intractable pneumothorax patients with pleural adhesions that may limit lung re-expansion, who are not candidates for surgery, MT combined with APC can be an alternative treatment option.