145 research outputs found
Electrochemical Formation of Nd–Ni Alloys in Molten CaCl₂–NdCl₃
Published on behalf of The Electrochemical Society by IOP Publishing Limited. The electrochemical formation of Neodymium–Nickel (Nd–Ni) alloys was investigated in a molten CaCl₂–NdCl₃ (1.0 mol%) system at 1123 K. Cyclic voltammograms for Molybdenum (Mo) and Ni electrodes showed the electrodeposition/dissolution of metallic Nd and the formation/dissolution of Nd–Ni alloys, respectively. The equilibrium potential of Nd³³+/Nd was determined at 0.27 V (vs. Ca²²+/Ca) by open-circuit potentiometry for a Mo electrode. The potentials of 0.48, 0.68, and 0.95 V, corresponding to the two-phase coexisting states of (NdNi₂ + NdNi₃), (NdNi₃ + NdNi₅), and (NdNi₅ + Ni), respectively, were confirmed using energy-dispersive X-ray spectroscopy and X-ray diffraction of the Ni electrode electrolyzed samples. The optimum electrolysis conditions for the Nd and Dysprosium (Dy) separation were discussed, and the standard Gibbs energies of formation were calculated for Nd–Ni alloys
Electrochemical Formation of Dy–Ni Alloys in Molten CaCl2–DyCl3
The electrochemical formation of Dy–Ni alloys was investigated in molten CaCl2–DyCl3 (1.0 mol%) at 1123 K. Cyclic voltammetry indicated the formation of Dy–Ni alloys at more negative than 1.0 V vs. Ca2+/Ca. Higher cathodic currents were observed from approximately 0.6 V, which indicated the formation of Dy–Ni alloys having higher Dy concentration. An open-circuit potentiometry was carried out with Mo and Ni electrodes before and after the addition of DyCl3. After the potentiostatic electrolysis of Mo electrode at −0.50 V for 30 s in molten CaCl2–DyCl3, only one potential plateau appeared at 0.33 V, which was interpreted as the equilibrium potential of Dy3+/Dy. In contrast, four potential plateaus were observed at 0.49, 0.62, 0.87, and 1.04 V for Ni electrode after the potentiostatic electrolysis at 0.25 V for 15 min. According to energy-dispersive X-ray spectroscopy and X-ray diffraction of the electrolyzed samples, the four potential plateaus correspond to the two-phase coexisting states of (DyNi + DyNi2), (DyNi2 + DyNi3), (DyNi3 + DyNi5), and (DyNi5 + Ni). Standard Gibbs energies of formation were calculated for Dy–Ni alloys
Fusion of Ni Plating on CP-Titanium by Electron Beam Single-Track Scanning: Toward a New Approach for Fabricating TiNi Self-Healing Shape Memory Coating
The limited wear resistance of commercially pure titanium (CP-Ti) hinders its use in abrasive and erosive environments, despite its good strength–weight ratio and corrosion resistance. This paper reports the first study proposing a novel method for wear-resistant TiNi coating through Ni plating and electron beam (EB) irradiation in an in situ synthetic approach. Single-track melting experiments were conducted using the EB to investigate the feasibility of forming a TiNi phase by fusing the Ni plate with the CP-Ti substrate. Varying beam powers were employed at a fixed scanning speed to determine the optimal conditions for TiNi phase formation. The concentration of the melt region was found to be approximate as estimated from the ratio of the Ni-plate thickness to the depth of the melt region, and the region with Ni-48.7 at.% Ti was successfully formed by EB irradiation. The study suggests that the mixing of Ti atoms and Ni atoms was facilitated by fluid flow induced by Marangoni and thermal convections. It is proposed that a more uniform TiNi layer can be achieved through multi-track melting under appropriate conditions. This research demonstrates the feasibility of utilizing EB additive manufacturing as a coating method and the potential for developing TiNi coatings with shape memory effects and pseudoelasticity.Wang L., Okugawa M., Konishi H., et al. Fusion of Ni Plating on CP-Titanium by Electron Beam Single-Track Scanning: Toward a New Approach for Fabricating TiNi Self-Healing Shape Memory Coating. Materials 16, 5449 (2023); https://doi.org/10.3390/ma16155449
Effect of Asian dust on pulmonary function in adult asthma patients in western Japan: A panel study
AbstractBackgroundAsian dust (AD) has become a major health concern. The concentration of AD is typically expressed in particulate matter less than 10 μm (PM10) and 2.5 μm (PM2.5). However, PM10 and PM2.5 consist of various substances besides AD. Light detection and ranging (LIDAR) systems can selectively measure the quantity of AD particles to distinguish non-spherical airborne particles from spherical airborne particles. The objective of this study was to investigate the relationship between pulmonary function in adult asthma patients and AD using LIDAR data.MethodsSubjects were 231 adult asthma patients who had their morning peak expiratory flow (PEF) measured from March to May 2012. A linear mixed model was used to estimate the association of PEF with sand dust particles detected by LIDAR.ResultsIncreases in the interquartile range of AD particles (0.018 km−1) led to changes in PEF of −0.42 L/min (95% confidence interval [CI], −0.85 to 0.01). An increase of 11.8 μg/m3 in suspended particulate matter and 6.9 μg/m3 in PM2.5 led to decreases of −0.17 L/min (−0.53 to 0.21) and 0.03 L/min (−0.35 to 0.42), respectively. A heavy AD day was defined as a day with a level of AD particles >0.032 km−1, which was the average plus one standard deviation during the study period, and six heavy AD days were identified. Change in PEF after a heavy AD day was −0.97 L/min (−1.90 to −0.04).ConclusionsHeavy exposure to AD particles was significantly associated with decreased pulmonary function in adult asthma patients
Impact of admission glycemia and glycosylated hemoglobin A1c on long-term clinical outcomes of non-diabetic patients with acute coronary syndrome
AbstractBackgroundAdmission glucose levels have proven to be a predictor in patients with acute myocardial infarction and elevated glycosylated hemoglobin A1c (HbA1c) is associated with an increased risk of cardiovascular disease, even in patients without diabetes. However, the effect of both admission glucose and HbA1c levels on clinical outcomes in non-diabetic patients with acute coronary syndrome (ACS) has not been fully elucidated. We evaluated the combined effect of admission glucose and HbA1c values on long-term clinical outcomes in non-diabetic patients with ACS treated with percutaneous coronary intervention (PCI).Methods and resultsThis was an observational study of 452 consecutive non-diabetic patients with ACS who underwent PCI between January 1997 and December 2006. The patients were assigned to four groups according to the median values of admission glucose and HbA1c. The primary endpoint comprising a composite of all-cause death and non-fatal MI was compared among the four groups. The primary endpoint occurred in 13.3% of the participants during a median follow-up period of 4.7 years. The cumulative incidence rate of primary endpoint significantly differed among the groups (p=0.048). Multivariable Cox regression analysis showed that the combination of elevated admission glucose and HbA1c was independently associated with long-term clinical outcomes.ConclusionsCombined admission glucose and HbA1c values were independently associated with clinical outcomes in non-diabetic patients with ACS treated with PCI
Electrochemical Formation of Nd-Ni Alloys in Molten LiF-CaF₂-NdF₃
The electrochemical formation of Nd-Ni alloys was investigated in a molten LiF-CaF₂-NdF₃ (0.30 mol%) system at 1123 K. Cyclic voltammetry and open-circuit potentiometry indicated the formation of several phases of Nd-Ni alloys. The whole electrode became almost NdNi₂ 2 phase by potentiostatic electrolysis of a 0.2 mm-thick Ni plate at 0.15 V vs. Li+/Li for 75 minutes. The formed NdNi₂ electrodes were transformed to other phases such as NdNi₃ and NdNi₅. The existences of NdNi₂, NdNi₃ and NdNi₅ were confirmed by powder XRD analysis. By summarizing the results, the formation potential for each alloy phase has been determined
早期糖尿病性腎症での腎臓におけるα-Klotho 発現の低下とその尿中カルシウム排世に対する役割についての検討
Hypercalciuria is one of the early manifestations of diabetic nephropathy. We explored here the role of α-Klotho, a protein expressed predominantly in distal convoluted tubules that has a role in calcium reabsorption. We studied 31 patients with early diabetic nephropathy and compared them with 31 patients with IgA nephropathy and 7 with minimal change disease. Renal α-Klotho expression was significantly lower and urinary calcium excretion (UCa/UCr) significantly higher in diabetic nephropathy than in IgA nephropathy or minimal change disease. Multiple regression analyses indicated that α-Klotho mRNA was inversely correlated with calcium excretion. We next measured these parameters in a mouse model of streptozotocin (STZ)-induced diabetic nephropathy, characterized by glomerular hyperfiltration, as seen in early diabetic nephropathy. We also confirmed a reduction of renal α-Klotho mRNA down to almost 50% and enhanced calcium excretion in mice with STZ-induced diabetic nephropathy in comparison with nondiabetic mice. Hypercalciuria was exacerbated in heterozygous α-Klotho knockout mice in comparison with wild-type mice, each with STZ-induced diabetic nephropathy. Thus, α-Klotho expression was decreased in distal convoluted tubules in diabetic nephropathy in humans and mice. Renal loss of α-Klotho may affect urinary calcium excretion in early diabetic nephropathy.博士(医学)・乙第1293号・平成24年5月28日© 2012 International Society of Nephrolog
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