Hydrogen production using thermochemical water-splitting Iodine–Sulfur process test facility made of industrial structural materials: Engineering solutions to prevent iodine precipitation

A thermochemical water-splitting iodine–sulfur process offers the potential for mass-producing hydrogen at high-efficiency levels, and it uses high-temperature heat sources, including high-temperature gas-cooled reactors, solar heat, and waste heat of industries. The raw material (H₂O) is split into H₂ and O₂ by combining three chemical reactions using sulfur and iodine. Currently, R&D tasks are essential to confirm the integrity of the components that are made of practical structural materials and the stability of hydrogen production in harsh working conditions. A test facility for producing hydrogen was constructed from corrosion-resistant components that are developed using industrial materials. In addition, for stable hydrogen production, technical issues for instrumental improvements (i.e., stable pumping of the hydrogen iodide (HI)–I₂–H₂O solution without locking the shaft seal, prevention of leakage by improving the quality control of glass-lined steel, prevention of I₂ precipitation using a water removal technique in a Bunsen reactor) were solved. The entire process was successfully operated for 150 h at the rate of ca. 30 L/h. The integrity of components made of practical structural materials and the operational stability of the hydrogen production facility in harsh working conditions were demonstrated.     

High response torque control of IPMSM using state feedback control based on n‐t coordinate system

This paper proposes a torque control method for interior permanent magnet synchronous motors (IPMSMs). The proposed method uses state feedback control based on a new n‐t coordinate system and controls the voltage amplitude and phase based on the coordinate system. The t‐axis is a tangent line of the constant voltage ellipse, and the n‐axis is a normal line of the ellipse. The n‐axis current is utilized to place the poles of the transfer function at the desired position and reduce the mutual coupling between the voltage amplitude controller and phase controller. The proposed method realizes a high torque response even under parameter variation for the linear range and over‐modulation range of the inverter, including a 6‐step mode. The effectiveness of the proposed method was verified by simulation and experimental results.     

Origin of the thermal plasticity property of zirconium oxide gels for use in direct thermal nanoimprinting

Some types of oxide gels derived from solutions exhibit a thermal plasticity property. In our previous report, the thermal plasticity property was utilized to produce oxide patterns and thin film transistors. However, it was not clear why some oxide gels exhibited a thermal plasticity property. In this report, we prepared not only a plastic ZrO₂ gel but also a non-plastic ZrO₂ gel, and investigated the structural and thermal properties of these gels to clarify why some gels exhibit a thermal plasticity property. We identified a clustered structure in ZrO₂ gels, with a Zr-O-Zr core coordinated by organic ligands. This structure was strongly related to the thermal plasticity property. The thermal plasticity property of ZrO₂ gel resulted from desorption and oxidization of the extra ligands by heating. We determined that the plastically deformed gels were consisted of clusters, and that the behaviour of ligands was a trigger in making a gel plastically deformed.     

FreeFEM++ code for reaction-diffusion equation–based topology optimization: for high-resolution boundary representation using adaptive mesh refinement

Structural and Multidisciplinary Optimization - In this article, we present a simple FreeFEM++ code to represent high-resolution boundaries of the optimal shape using reaction-diffusion...     

Trifluoromethyl Dihydrothiazine-Based β-Secretase (BACE1) Inhibitors with Robust Central β-Amyloid Reduction and Minimal Covalent Binding Burden

The β-site amyloid precursor protein cleaving enzyme 1 (BACE1, also known as β-secretase) is a promising target for the treatment of Alzheimer's disease. A pK_a lowering approach over the initial leads was adopted to mitigate hERG inhibition and P-gp efflux, leading to the design of 6-CF₃ dihydrothiazine 8 (N-(3-((4S,6S)-2-amino-4-methyl-6-(trifluoromethyl)-5,6-dihydro-4H-1,3-thiazin-4-yl)-4-fluorophenyl)-5-cyanopicolinamide). Optimization of 8 led to the discovery of 15 (N-(3-((4S,6S)-2-amino-4-methyl-6-(trifluoromethyl)-5,6-dihydro-4H-1,3-thiazin-4-yl)-4-fluorophenyl)-5-(fluoromethoxy)pyrazine-2-carboxamide) with an excellent balance of potency, hERG inhibition, P-gp efflux, and metabolic stability. Oral administration of 8 elicited robust Aβ reduction in dog even at 0.16 mg/kg. Reflecting the reduced hERG inhibitory activity, no QTc prolongation was observed at high doses. The potential for reactive metabolite formation of 15 was realized in a nucleophile trapping assay using [¹⁴C]-KCN in human liver microsomes. Utilizing covalent binding (CVB) in human hepatocytes and the maximum projected human dosage, the daily CVB burden of 15 was calculated to be at an acceptable value of below 1 mg/day. However, hepatotoxicity was observed when 15 was subjected to a two-week tolerance study in dog, which prevented further evaluation of this compound.     

Stress corrosion cracking of copper in swollen bentonite simulating nuclear waste disposal environment

Stress corrosion cracking (SCC) of pure copper in bentonite clay was examined using a slow strain rate test (SSRT). Bentonite was swollen with pure water or aqueous solutions containing NH₃ of 5 and 10 mM. Thick corrosion films and particulate deposits were formed on the copper surface after the SSRT. Typical tarnish rupture-type SCC occurred on pure copper in swollen bentonite with and without NH₃. The crack propagation rate was enhanced by NH₃. It is confirmed that a thick oxide layer was formed on copper during plastic deformation, resulting in tarnish crack-type SCC. Many particulate deposits observed on the surface were formed due to the rapid dissolution of Cu²⁺ ions to form porous CuO at local deformed sites, regardless of the SCC occurrence.     

生态与经济的共生——祝贺《中国园林》创刊25周年

<正>首先衷心祝贺《中国园林》创刊25周年!作为国际编委,能够拜读每期贵刊,我深感荣幸,值此机会想介绍日本社会和园林景观的最新动态,希望能给中国的读者一些参考。     

Liqsedflow: Role of Two-Phase Physics in Subaqueous Sediment Gravity Flows

The paper describes an extension of the computational code LIQSEDFLOW proposed by the authors. The salient features of the code lie in its capability to describe the multi-phased physics of subaqueous sediment gravity flows. Specifically, it combines Navier-Stokes/continuity equations and equations for the advection and hindered settling of grains for a liquefied soil domain, with a consolidation equation for the underlying, progressively solidifying soil domain via a transition layer characterized by zero effective stress and a small yet discernible stiffness. Evolutions of the flow and solidification surfaces are traced as part of the solution using a volume-of-fluid (VOF) technique. The predicted features of the gravity flows of initially fluidized sediments with different concentrations conform to the observed performances in two-dimensional flume tests. The present results demonstrate the crucial role of two-phase physics, particularly solidification, in reproducing the concurrent processes of flow stratification, deceleration, and redeposition in subaqueous sediment gravity flows.     

Role of Neuroinflammation and Blood-Brain Barrier Permutability on Migraine

Currently, migraine is treated mainly by targeting calcitonin gene-related peptides, although the efficacy of this method is limited and new treatment strategies are desired. Neuroinflammation has been implicated in the pathogenesis of migraine. In patients with migraine, peripheral levels of pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α, are known to be increased. Additionally, animal models of headache have demonstrated that immunological responses associated with cytokines are involved in the pathogenesis of migraine. Furthermore, these inflammatory mediators might alter the function of tight junctions in brain vascular endothelial cells in animal models, but not in human patients. Based on clinical findings showing elevated IL-1β, and experimental findings involving IL-1β and both the peripheral trigeminal ganglion and central trigeminal vascular pathways, regulation of the Il-1β/IL-1 receptor type 1 axis might lead to new treatments for migraine. However, the integrity of the blood-brain barrier is not expected to be affected during attacks in patients with migraine.