Kinetics Study of Adsorption Behaviors of Trivalent Metal Ions onto Chelating Resin: Comparison between Scandium(III) and Other Metal Ions

Scandium (Sc) lacks commercially viable independent deposits and is mainly recovered as a by-product of the smelting of other ores. In the process of recovering nickel from laterite ores, Sc is recovered from leaching solutions. The recovery of Sc requires its efficient separation and purification from other impurities. This study proposes a process for the selective separation and recovery of Sc from other trivalent cations in sulfuric acid solutions using an iminodiacetic acid chelating resin, Diaion™ CR11. The adsorption behaviors of trivalent ions Sc(III), Cr(III), Al(III), and Fe(III) onto CR11 in single- and multiple-metal systems were investigated to determine the appropriate Sc separation conditions. In systems containing single metal ions, pseudo-first-order and pseudo-second-order kinetic models were used to fit the data. Linear and nonlinear methods were used for fitting. The activation energies were calculated from the rate constants at a pH of 2.0 and at three different temperatures of 23℃, 60℃, and 80℃ and followed the order: Cr(III) > Fe(III) > Sc(III) > Al(III). In binary systems including Sc(III), the simultaneous adsorption of Sc(III) and other trivalent ions onto CR11 was investigated. Previously adsorbed Sc(III) on CR11 was displaced by the subsequent adsorption of Fe(III) or Cr(III) from the solution. The affinity of the metal ions to iminodiacetic acid and the adsorption reaction rate were critical factors for suitable selective Sc separation, indicating that prior removal of Fe(III) was necessary. Column experiments at 23℃ using a synthetic solution without Fe(III) showed that Cr(III) adsorption was suppressed, and that Sc(III) was efficiently adsorbed. Scandium can be efficiently recovered from a solution containing Sc(III) after prior removal of Fe(III) by adsorption at low temperature using CR11

Point Cloud Denoising and Outlier Detection with Local Geometric Structure by Dynamic Graph CNN

The digitalization of society is rapidly developing toward the realization of the digital twin and metaverse. In particular, point clouds are attracting attention as a media format for 3D space. Point cloud data is contaminated with noise and outliers due to measurement errors. Therefore, denoising and outlier detection are necessary for point cloud processing. Among them, PointCleanNet is an effective method for point cloud denoising and outlier detection. However, it does not consider the local geometric structure of the patch. We solve this problem by applying two types of graph convolutional layer designed based on the Dynamic Graph CNN. Experimental results show that the proposed methods outperform the conventional method in AUPR, which indicates outlier detection accuracy, and Chamfer Distance, which indicates denoising accuracy.Comment: 2023 IEEE 12th Global Conference on Consumer Electronics (GCCE 2023

Nonlinear optical responses in noncentrosymmetric superconductors

The unique nonreciprocal responses of superconductors, which stem from the Cooper pairs' quantum condensation, have been attracting attention. Recently, theories of the second-order nonlinear response in noncentrosymmetric superconductors were formulated based on the Bogoliubov-de Gennes theory. In this paper, we study the mechanism and condition for second-order optical responses of time-reversal symmetric superconductors. The numerical results show the characteristic photocurrent and second harmonic generation in the superconducting state. However, the superconductivity-induced nonlinear optical responses disappear under some conditions on pair potential. We show that the coexistence of intraband and interband pairing is necessary for the second-order superconducting optical responses. In addition, the superconducting Berry curvature factor, which is related to a component of Berry curvature in the superconducting state, is essential for the nonlinear responses. Thus, we derived the microscopic conditions where the superconducting nonlinear response appears.Comment: 21 pages and 9 figure

Molecular Rheology of Glassy Polymers (FUNDAMENTAL MATERIAL PROPERTIES-Molecular Rheology)

Molecular origin of the viscoelasticity around the glass transition zone is investigated by means of dynamic birefringence and dynamic viscoelasticity measurements. The present study show that the viscoelasticity around the glass transition zone has two molecular origins: One is the orientation relaxation of main chain axis and the other one is the rotational motion of structure units about the main chain axis

Sign change in c-axis thermal expansion and lattice collapse by Ni substitution in Co1-xNixZr2 superconductors

We investigated the structural, electronic, and superconducting properties of Co1-xNixZr2, in which c-axis thermal expansion is systematically controlled. At x (smaller than) 0.3, c-axis negative thermal expansion (NTE) was observed, and the thermal expansion constant {\alpha}c approached zero with increasing x. At x = 0.4-0.6, zero thermal expansion was observed, and positive thermal expansion (PTE) appeared for x (greater than) 0.7. By analyzing the c/a ratio, we observed a possible collapsed transition in the tetragonal lattice at around x = 0.6-0.8. The lattice collapse results in c-axis PTE and the suppression of bulk superconductivity.Comment: 16 pages, 5 figures, 1 table, Supporting material

Clinical Experience Using a Real Time Autofluorescence Endoscopy System in the Gastrointestinal Tract

Autofluorescence spectra of neoplastic tissues have been reported to be significantly different from those of normal tissues when excited by blue or violet light. From this concept, a light-induced autofluorescence endoscopic imaging system for gastrointestinal mucosa (LIFE-GI; Xillix, Canada and Olympus, Japan) has been newly developed and the clinical evaluation of the prototype system has been conducted in hospitals in Canada, Netherlands and Japan

The First Bipartisan Privacy Bill in the United States“ American Data Privacy and Protection Act” ―Its Submission progress and Features―

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EVALUATION OF TORQUE MOMENT IN ESTHETIC BRACKETS

Objectives: To examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires. Materials and Methods: This study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5–40° were examined. Results: The torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires. Conclusions: The current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires

Risk factors for anemia of prematurity among 30-35-week preterm infants

Background: The risk factors for anemia of prematurity (AOP) among late preterm infants are unelucidated. We identified risk factors for declining hemoglobin (Hb) concentration and triggering factors for AOP treatment in infants born at 30-35 gestational weeks. Methods: From 2012 to 2020, we conducted a single-center retrospective study of infants born at 30-35 weeks of gestation without congenital anomalies or severe hemorrhage. The primary outcome was AOP development, defined by initiation of treatments including red blood cell transfusion, subcutaneous injections of erythropoietin, and iron supplementation. A multivariable logistic regression model was used to investigate potential risk factors for AOP. Results: A total of 358 infants were included. Lower gestational age (odds ratio, 0.19; 95% confidence interval 0.11-0.32), small for gestational age (SGA; 7.17, 2.15-23.9), low maternal Hb level before birth (0.66, 0.49-0.87), low Hb at birth (0.71, 0.57-0.89), and multiple large blood samplings (1.79; 1.40-2.29) showed significantly higher odds for AOP development. Conclusions: Gestational age, SGA, low maternal Hb before birth, Hb at birth, and high number of large blood samplings were positively associated with AOP development in infants born at 30-35 gestational weeks