Alloy Design,Combinatorial Synthesis,and Microstructure–Property Relations for Low-Density Fe-Mn-Al-C Austenitic Steels

We present recent developments in the field of austenitic steels with up to 18% reduced mass density. The alloys are based on the Fe-Mn-Al-C system. Here, two steel types are addressed. The first one is a class of low-density twinning-induced plasticity or single phase austenitic TWIP (SIMPLEX) steels with 25–30 wt.% Mn and <4–5 wt.% Al or even <8 wt.% Al when naturally aged. The second one is a class of κ-carbide strengthened austenitic steels with even higher Al content. Here, κ-carbides form either at 500–600°C or even during quenching for >10 wt.% Al. Three topics are addressed in more detail, namely, the combinatorial bulk high-throughput design of a wide range of corresponding alloy variants, the development of microstructure–property relations for such steels, and their susceptibility to hydrogen embrittlement.     

Catalytic performance of Ni/CeO2/Al2O3 modified with noble metals in steam gasification of biomass

In the steam gasification of biomass, the additive effect of noble metals such as Pt, Pd, Rh and Ru to the Ni/CeO₂/Al₂O₃ catalyst was investigated. Among these noble metals, the addition of Pt was most effective even when the loading amount of added Pt was as small as 0.01 wt.%. In addition, the catalyst characterization suggests the formation of the Pt–Ni alloy over the Pt/Ni/CeO₂/Al₂O₃.     

Automatic electron beam alignment adjustment system and automatic filament current adjustment system for electron beam welder

Recently, the electron beam welders with high acceleration voltage (more than 100 kV) and high electrical power (more than 15 kW) have been reviewed the role of the high-energy electron beam density again, due to space or aircraft development or automobile industry desired high productivity and high accurate welding for saving energy. NEC group have supplied these electron beam welders. This time, the automatic alignment adjustment system of the electron beam orbit and the automatic adjustment system of filament current were developed and put to a practical use. As a result, the great effectiveness for the stability of welding quality was apparent.     

Flow properties and rheology of slag from coal gasification

We have studied the rheological characteristics of Texaco gasifier slag at high-temperature. Slag samples have been analyzed by X-ray fluorescence, X-ray diffraction, and scanning electron microscopy. The rheological behavior of the slag has been investigated experimentally using a high-temperature rheometer at temperatures between 1200 °C and 1340 °C. The effects of the shear rate and temperature on the rheological behavior of the slag have been explored. Moreover, the observed rheological behavior of the slag has been correlated with its solid-phase content, as calculated with the aid of the computer software package FactSage. The results show that the sensitivity of the slag viscosity to temperature decreases with increasing rotation speed. Above its liquidus temperature calculated by FactSage, the slag behaves as a Newtonian fluid; below its liquidus temperature, however, the rheological behavior of the slag becomes non-Newtonian owing to its increased solid-phase content. Meanwhile, Slag containing a number of crystalline particles shows dramatic shear-thinning and thixotropic behavior. Moreover, the shear-thinning behavior of the slag becomes ever more distinct as the temperature is decreased. The yield stress values of the slag and the number and particle size of the crystalline particles in the slag increase with decreasing temperature.     

Wall slip and melt-fracture of polystyrene melts in capillary flow

We investigated slip and unstable flow phenomena of polystyrene melts in capillaries from the view of the effects of temperature and molecular weight by using three polystyrene samples with different molecular weights (M_w = 192,000, M_w = 258,000, and M_w = 321,000). The slip velocities are estimated by the Mooney method and the modified Mooney method. We found that the slip velocity increases and the critical slip stress above which a slip starts to occur decreases with the temperature. We also observed the melt-fracture at above a critical melt-fracture stress higher than . We found that the onset of melt fracture is affected by the extensional stress near the entry region to the capillary in the barrel and the melt-fracture tends to easily occur with increase of the molecular weight, but is not sensitive to the temperature.     

Endothelin ETB Receptor-Mediated Astrocytic Activation: Pathological Roles in Brain Disorders

In brain disorders, reactive astrocytes, which are characterized by hypertrophy of the cell body and proliferative properties, are commonly observed. As reactive astrocytes are involved in the pathogenesis of several brain disorders, the control of astrocytic function has been proposed as a therapeutic strategy, and target molecules to effectively control astrocytic functions have been investigated. The production of brain endothelin-1 (ET-1), which increases in brain disorders, is involved in the pathophysiological response of the nervous system. Endothelin B (ET_B) receptors are highly expressed in reactive astrocytes and are upregulated by brain injury. Activation of astrocyte ET_B receptors promotes the induction of reactive astrocytes. In addition, the production of various astrocyte-derived factors, including neurotrophic factors and vascular permeability regulators, is regulated by ET_B receptors. In animal models of Alzheimer’s disease, brain ischemia, neuropathic pain, and traumatic brain injury, ET_B-receptor-mediated regulation of astrocytic activation has been reported to improve brain disorders. Therefore, the astrocytic ET_B receptor is expected to be a promising drug target to improve several brain disorders. This article reviews the roles of ET_B receptors in astrocytic activation and discusses its possible applications in the treatment of brain disorders.     

Extracellular Vesicles Taken up by Astrocytes

Extracellular vesicles (EVs) are composed of lipid bilayer membranes and contain various molecules, such as mRNA and microRNA (miRNA), that regulate the functions of the recipient cell. Recent studies have reported the importance of EV-mediated intercellular communication in the brain. The brain contains several types of cells, including neurons and glial cells. Among them, astrocytes are the most abundant glial cells in the mammalian brain and play a wide range of roles, from structural maintenance of the brain to regulation of neurotransmission. Furthermore, since astrocytes can take up EVs, it is possible that EVs originating from inside and outside the brain affect astrocyte function, which in turn affects brain function. However, it has not been fully clarified whether the specific targeting mechanism of EVs to astrocytes as recipient cells exists. In recent years, EVs have attracted attention as a cell-targeted therapeutic approach in various organs, and elucidation of the targeting mechanism of EVs to astrocytes may pave the way for new therapies for brain diseases. In this review, we focus on EVs in the brain that affect astrocyte function and discuss the targeting mechanism of EVs to astrocytes.     

Adsorption of urea,creatinine, and uric acid from three solution types using spherical activated carbon and its recyclability

In this paper, we propose that the urinary toxins from the wastewater be adsorbed on an adsorbent such as spherical activated carbon and the latter be regenerated by subjecting it to high temperatures to recycle activated carbon and also to recycle the water used in dialysis. We studied the adsorption of artificial waste dialysate, which is a mixed solution of urea, creatinine, and uric acid, and the separate solutions for each of these and found that their extents of adsorption onto the spherical activated carbon material were nearly identical. The amount of adsorption was approximately 1.4 mg·g^-1 for urea, 18 mg·g^-1 for creatinine, and 20 mg·g^-1 for uric acid. The urea, creatinine, and uric acid adsorbed onto the spherical activated carbon decomposed on heat treatment at 500℃, and the adsorption capacity of the spherical activated carbon was regenerated. Our study successfully demonstrated that the spherical activated carbon can be recycled in the waste dialysate treatment process.