Characteristics of dust aerosols inferred from lidar depolarization measurements at two wavelengths

Lidar depolarization measurements were performed simultaneously at two wavelengths (532 and 1064 nm) in an Asian dust event. The observed particle depolarization ratio for 1064 nm was generally larger than that for 532 nm, and it was found that the mixing of Asian dust and other spherical aerosols must be taken into account. A simple two-component theory considering two types of aerosol (dust and spherical aerosols) was developed and applied to the observed data. The mixing ratio of dust and the backscatter-related Angstr?m exponents for dust and spherical aerosols was derived. These parameters can be used to infer characteristics of the aerosols and the mixed states.     

Highly purified hydrogen production from ammonia for PEM fuel cell

Liquid ammonia is an attractive hydrogen carrier because of high storage capacity. According to ISO14687-2, an acceptable ammonia concentration in hydrogen for polymer electrolyte membrane (PEM) fuel cell vehicles is 0.1 ppm. When ammonia is used as the hydrogen carrier, about 1000 ppm of ammonia included in gas generated by ammonia decomposition at 773–823 K and 0.1 MPa has to be reduced to less than 0.1 ppm. Although several types of ammonia absorption materials are investigated as ammonia remover, the target value cannot be achieved by static adsorption methods. However, we have succeeded in that the ammonia concentration is reduced down to 0.01–0.02 ppm by using Li-exchange X-type zeolite (Li-X) as the absorbent and dynamic adsorption methods. Furthermore, Li-X is simply recycled by heating at 673 K. Therefore, Li-X is a durable and recyclable ammonia removal material for the highly purified hydrogen production from ammonia for PEM fuel cells.     

Static strength of hot-stamped spot welded joints: study on spot welding tailored blank technology

Hot stamping spot welding tailored blank technology is a process to produce spot welded automotive body parts by the following process: spot welding steel sheets in lap configuration → hot stamping (heating to about 900°C) → quenching and forming in water-cooled die → shot blasting to remove scale. This process has the advantage of producing high strength lap welded automotive body parts without increasing the number of forming dies. In this study, the mechanical properties of the hot stamped spot weld (spot welding → hot stamping) and conventional spot weld (hot stamping → spot welding) of the 1500 MPa class uncoated boron steel sheets were compared. The obtained results are as follows. The tensile shear strength (TSS) of the hot-stamped spot weld and conventional spot weld were comparable and the fracture modes were the same. On the other hand, the cross tension strength (CTS) of hot-stamped spot weld was significantly higher than that of the conventional spot weld. The fracture position of the hot-stamped spot weld was outside the nugget and conventional spot weld was inside the nugget. The high CTS of the hot-stamped spot welds might be caused by the improvement of the fracture toughness of the nugget, which was caused by reduction of the solidification segregation of the phosphorus. It is assumed that the heating process after spot welding leads to the reduction of the solidification segregation. For the tension test because there was no HAZ softening in the hot-stamped spot weld, no fracture was observed in HAZ and a higher elongation was obtained.     

Flow characteristics of a cold helium arc-jet plasma along open field lines

We experimentally study plasma parameters including ion acoustic Mach number of expanding cold helium plasma jet with an electron temperature of less than 1 eV flowing along open field lines. It is experimentally found that the ion Mach number increases from 1 to 3, and that the plasma potential decreases by about 1 V. We discuss the experimental results based on a quasi one-dimensional flow model in which the plasma is assumed to be quasi-neutral and in a state of thermodynamic equilibrium. Our model describes the ion acceleration, the axial profiles of the potential drop, and the electron temperature/density. The model also shows that the helium ions are accelerated both by the electric field and by the increasing cross-sectional area of the transonic flow. After the ion acceleration, the ion Mach number decreases and the electron temperature increases. These phenomena are discussed in terms of a shock wave. It is noted that the electron density decreases even in the shock wave. This is discussed in terms of rapid recombination because of the low electron temperature. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Cancer Cachexia: Its Mechanism and Clinical Significance

The term “cachexia” is derived from the Greek words kakos (bad) and hexis (habit). Cachexia is a malnutrition associated with chronic diseases such as cancer, chronic heart failure, chronic renal failure, and autoimmune diseases, and is characterized by decreased skeletal muscle mass. Cancer cachexia is quite common in patients with advanced cancer. Weight loss is also a characteristic symptom of cancer cachexia, along with decreased skeletal muscle mass. As nutritional supplementation alone cannot improve cachexia, cytokines and tumor-derived substances have been attracting attention as its relevant factors. Cancer cachexia can be also associated with reduced chemotherapeutic effects, increased side effects and treatment interruptions, and even poorer survival. In 2011, a consensus definition of cachexia has been proposed, and the number of relevant research reports has increased significantly. However, the pathogenesis of cachexia is not fully understood, and there are currently few regulatory-approved standard treatments for cachexia. The main reason for this is that multiple etiologies are involved in the development of cachexia. In this review, we will outline the current status of cachexia, the mechanisms of which have been elucidated in recent years, especially from the perspective of advanced cancer.     

Organocatalytic Enantioselective Hydrophosphonylation of Sulfonylimines having a Heteroarenesulfonyl Group as a Novel Stereocontroller

Organocatalytic enantioselective hydrophosphonylation of imines having the a heteroarenesulfonyl group afforded the respective products with high enantioselectivity. Both enantiomers of α‐amino phosphonates were obtained by using different Cinchona alkaloids with up to 98% ee.     

Survey of synthetic disinfectants in grapefruit seed extract and its compounded products

Grapefruit seed extract (GSE), derived from the seeds of grapefruit (Citrus paradisi MCAF.), is listed as a natural food additive in Japan. Products containing GSE are used as disinfectants made from only natural sources, especially after Japanese researchers found that GSE prevents the growth of norovirus. On the other hand, recent overseas studies indicated that synthetic disinfectants, such as benzalkonium and benzethonium chlorides, were present in some commercial GSE products. To confirm the quality of commercial GSE products available in Japanese markets, we carried out comprehensive research to identify the major constituents of commercial GSE products which are used as food additives (13 products from 6 manufacturers), dietary supplements (5 products from 4 manufacturers), cosmetic materials (16 products from 10 manufacturers) and disinfectant or deodorant sprays (7 products from 7 manufacturers). By means of NMR and LC/MS analysis, synthetic disinfectants such as benzethonium or benzalkonium salts were detected in most of the commercial GSE products.     

Structures and N2-sorption properties of carbonaceous films prepared by high-powered sputtering of d-phenylalanine

Amino acid-based carbonaceous films were prepared by the radio-frequency (rf) sputtering of d-phenylalanine under the rf power density from 0.18 to 0.53 W/cm². As the rf power was increased, the deposition rate tended to increase, especially for 120-W sputtering. The surface of carbonaceous films prepared by high rf power have rugged surfaces following their storage in a vacuum box. The carbonization of the sputtered films progressed with rf power; the oxygen and nitrogen content in the films decreased as rf power increased, as well as the content of CH moieties decreased. Increasing the rf sputtering power enhanced the N₂-sorption capability and the viscous character of the carbonaceous films. The quartz crystal resonators coated with the carbonaceous films by the highest rf sputtering power had superior resonance signals toward the N₂ sorption-desorption measurement with suppressed noise.     

Transport Properties of Two-dimensional Snowballs Below the Surface of 4He-II Under Rotation

Kelvin-waves play an important role for the dissipation of quantum turbulence at low temperatures. Here the plasma resonance of two-dimensional (2D) snowballs trapped below the surface of rotating superfluid ⁴He are measured for the first time in order to examine whether 2D snowballs could be a new probe for study of vortex dynamics. Below 200 mK, a positive shift of the resonant frequency f ₁ and linewidth broadening are observed as small variations in the absorption spectra under rotation. Both f ₁ and the linewidth Δf increase linearly with the rotation speed, and the slopes of f ₁ and Δf against the rotation speed have no temperature dependence. The increase of Δf suggests that an additional dissipation is caused by the coupling between the snowballs and vortices. We provide a qualitative explanation for the linear increase of Δf in the context of Kelvin-waves excited by the motion of snowballs.