Electrochemical reduction of carbon dioxide in methanol at ambient temperature and pressure

The electrochemical reduction of carbon dioxide was studied in methanol-based supporting electrolytes on various metal electrodes at ambient temperature and pressure. The ionophore of the catholyte was benzalkonium chloride, [RN(CH3)2CH2C6H5]⁺Cl^–, where R=C8–C18, the chain length being distributed around C14. A divided H-type cell was used, the supporting electrolytes were 10–2moldm–3 benzalkonium chloride in double distilled methanol (catholyte) and a 10–1moldm–3 aqueous KHCO3 solution (anolyte). Nine different, high purity (>99.5%) metal electrodes were used: Ti, Fe, Co, Ni, Pt, Ag, Au, Zn and Sn. Carbon monoxide, methane and ethane were the main organic products. Silver, Au, Zn and Sn cathodes allowed for the best faradaic yields of CO production, the maximum amount of CO (71%, 185 mmol) being formed on the Ag electrode. Methane evolved on each of the nine tested electrodes, with current yields in the range from 0.2 to 3.0%. Ethane and ethylene were produced on the nickel electrode, with low faradaic efficiencies, 0.5 and 0.3%, respectively. No dimerization products were detected. This research can contribute to large-scale manufacturing of useful organic products from a readily available and cheap raw material: CO2-saturated methanol from industrial absorbers (the Rectisol process).     

The adhesion between electrolessly deposited copper and a photoimageable polymer

We investigated the relationship between the peel adhesion of copper, deposited by electroless plating, to a photoimageable polymer and the time of chemical etching before plating. Mechanical interlocking is generally considered as being the adhesion mechanism between deposited metals and substrates. However, we found that the peel strength decreased with an increase in the etching time though the polymer roughness did not change. The glass transition temperature of the photoimageable polymer became lower as the etching time increased. The pretreatment not only roughened the surface of the photoimageable polymer, but also affected the bulk polymer and the adhesion.     

Investigation of shielding method of ELF magnetic field generated from conductors

We have studied experimentally the shielding method of ELF magnetic field applied to the source of line conductors. For the single‐phase line current, it appears to be difficult to achieve effective shielding. On the other hand, for the balanced three‐phase conductors, including triangle and twisted configuration, a certain reduction of generated magnetic field was achieved by adjusting the configuration of conductors or by surrounding the conductors with cylindrical shielding materials made of ferromagnetic materials or nonferromagnetic metals. Normalized characteristics between phase current, distance between source current and observation point, distance between phase conductors, and the pitch of twisted cable were derived. In addition, the effect of unbalanced current was also investigated. © 2000 Scripta Technica, Electr Eng Jpn, 131(2): 12–19, 2000     

Temperature distribution along stack in an acoustic-resonance tube: discussions on advanced linearized theory

Verification of the applicability of the linearized thermoacoustic theory proposed in 1988 by Swift, J. Acoust. Soc. Am., 84 , (4), 1145–1180, to an acoustic- resonance tube refrigerator and discussions on the advanced linearized theory were conducted through a comparison with the measured temperature distribution along the stack in a simulated acoustic-resonance tube. The measured temperature in all cases of various stack configurations such as stack plate spacing and length showed an almost linear distribution along the stack, while Swift's linearized theory gave a curved distribution with relatively large deviation from experimental data. Eddy diffusivity and/or steady streaming effects excited by sound waves were taken into account in the linearized model, and the effects of these terms on the prediction of temperature distribution were examined. The agreement between theory and experiment was markedly improved by the introduction of steady streaming. This provided a guideline for the construction of an advanced linearized theory. © 1999 Scripta Technica, Heat Trans Jpn Res, 27(8): 551–567, 1998     

Natural Compounds Attenuate Denervation-Induced Skeletal Muscle Atrophy

The weight of skeletal muscle accounts for approximately 40% of the whole weight in a healthy individual, and the normal metabolism and motor function of the muscle are indispensable for healthy life. In addition, the skeletal muscle of the maxillofacial region plays an important role not only in eating and swallowing, but also in communication, such as facial expressions and conversations. In recent years, skeletal muscle atrophy has received worldwide attention as a serious health problem. However, the mechanism of skeletal muscle atrophy that has been clarified at present is insufficient, and a therapeutic method against skeletal muscle atrophy has not been established. This review provides views on the importance of skeletal muscle in the maxillofacial region and explains the differences between skeletal muscles in the maxillofacial region and other regions. We summarize the findings to change in gene expression in muscle remodeling and emphasize the advantages and disadvantages of denervation-induced skeletal muscle atrophy model. Finally, we discuss the newly discovered beneficial effects of natural compounds on skeletal muscle atrophy.     

Mechanical properties of Si nanowires as revealed by in situ transmission electron microscopy and molecular dynamics simulations

Deformation and fracture mechanisms of ultrathin Si nanowires (NWs), with diameters of down to ~9 nm, under uniaxial tension and bending were investigated by using in situ transmission electron microscopy and molecular dynamics simulations. It was revealed that the mechanical behavior of Si NWs had been closely related to the wire diameter, loading conditions, and stress states. Under tension, Si NWs deformed elastically until abrupt brittle fracture. The tensile strength showed a clear size dependence, and the greatest strength was up to 11.3 GPa. In contrast, under bending, the Si NWs demonstrated considerable plasticity. Under a bending strain of <14%, they could repeatedly be bent without cracking along with a crystalline-to-amorphous phase transition. Under a larger strain of >20%, the cracks nucleated on the tensed side and propagated from the wire surface, whereas on the compressed side a plastic deformation took place because of dislocation activities and an amorphous transition.     

Analysis of Cs-adsorption behavior using a column filled with microcapsule beads of potassium copper hexacyanoferrate

Ash-washing technology is a crucially important technology for removing radioactive Cs from contaminated ash. For that technology, Cs⁺ removal from the ash-washing solution by the adsorbent is necessary. This study was conducted to establish rapid preparation of appropriate adsorption columns for Cs⁺ uptake. A one-site model was not used for analysis because the model cannot accommodate sites with different adsorption speed. Results demonstrated that the adsorption behavior of the column filled with the granules of potassium copper hexacyanoferrate was well reproduced by a two-site adsorption model with parameters chosen through analysis of batch adsorption test results.     

High-Temperature Mechanical Behavior and Fracture Analysis of a Low-Carbon Steel Related to Cracking

Cracking in continuously cast steel slabs has been one of the main problems in casting for decades. In recent years, the use of computational models has led to a significant improvement in caster performance and product quality. However, these models require accurate thermomechanical properties as input data, which are either unreliable or nonexistent for many alloys of commercial interest. A major reason for this lack of reliable data is that high-temperature mechanical properties are difficult to measure. Several methods have been developed to assess the material strength during solidification, especially for light alloys. The tensile strength during solidification of a low carbon aluminum-killed (LCAK; obtained from Tata Steel Mainland Europe cast at the DSP plant in IJmuiden, the Netherlands) has been studied by a technique for high-temperature tensile testing, which was developed at Sumitomo Metal Industries in Japan. The experimental technique enables a sample to melt and solidify without a crucible, making possible the accurate measurement of load over a small solidification temperature range. In the current study, the tensile test results are analyzed and the characteristic zero-ductility and zero-strength temperatures are determined for this particular LCAK steel grade. The fracture surfaces are investigated following tensile testing, which provides an invaluable insight into the fracture mechanism and a better understanding with respect to the behavior of the steel during solidification. The role of minor alloying elements, like sulfur, in hot cracking susceptibility is also discussed.     

HCl emission during co-pyrolysis of demolition wood with a small amount of PVC film and the effect of wood constituents on HCl emission reduction

In this study, HCl emission during the co-pyrolysis of demolition wood and a small amount of polyvinyl chloride (PVC) film (the Cl content of which ranged from 0.5% to 6% by weight) in an N₂ atmosphere at elevated temperatures of up to 600 °C was measured using a laboratory-scale cylindrical batch reactor. In the pyrolysis experiments, HCl emission was reduced by the presence of wood. The effect of the primary constituents of wood (cellulose, hemicellulose, and lignin) on HCl emission was investigated by not only measuring HCl emission and Cl distribution to various phases during the co-pyrolysis of each constituent with PVC film but also by conducting thermogravimetric analysis of the constituents. This investigation first revealed that hemicellulose significantly reduced HCl emission by fixing most of the Cl molecules in a sample into pyrolyzed residue.     

Effect of highly lipolyzed goat cheese on HL-60 human leukemia cells: antiproliferative activity and induction of apoptotic DNA damage

To establish cheese as a dairy product with health benefits, we embarked on examining the multifunctional role of cheeses, especially in the field of cancer prevention. The current study was designed to investigate whether different types of commercial goat cheeses may possess antiproliferative activity, using an HL-60 human promyelocytic leukemia cell line as a cancer cell model. Among 11 cheese extracts tested at 500μg/mL, 6 (Crottin de Chavignol, Pouligny Saint-Pierre, Chabichou du Poitou, Valencay, Kavli, and Sainte-Maure de Touraine) resulted in a significant decrease of cell viability, which is consistent with a decrease in viable cell number. Compared with the half-maximal inhibitory concentration (IC(50)) value of individual cheeses in cellular proliferation assays, the Pouligny Saint-Pierre extract showed strong inhibition. Incubation of cells in the presence of Pouligny Saint-Pierre extract resulted in induction of cellular morphological changes and apoptotic DNA fragmentation as well as expression of the active form of caspase-3 protein. Based on the quantification of the ratio of free fatty acids to triglycerides in different cheese samples, a significant correlation was detected between lipolytic ripeness and IC(50) values for antiproliferative capacity tested in HL-60 cells. Collectively, these results support a potential role of highly lipolyzed goat cheeses in the prevention of leukemic cell proliferation.