Fabrication of high thermal conductivity copper/diamond composites by electrodeposition under potentiostatic conditions

High thermal conductivity Cu/diamond composites were fabricated using an electrodeposition technique. The electrodes were oriented horizontally, and the cathode was located at the bottom of the plating bath. Diamond particles (10-230 mu m) were first precipitated on the cathode substrate, and then copper was electrodeposited on the substrate to fill the gap between the precipitated diamond particles, which resulted in the formation of a Cu/diamond composite. The deposition behavior of the copper was electrochemically investigated, and the current densities of copper deposition under galvanostatic conditions were estimated. The current densities for the substrate with diamond particle layers were 4-10 times higher than the current density for the substrate without diamond particle layers, which led to undesired hydrogen evolution. Cu/diamond composites were formed under potentiostatic conditions without hydrogen evolution, and the resultant composites had compact morphologies. A specimen containing 49 vol% diamond particles with a mean diameter of 230 mu m had the highest thermal conductivity of 600 W m(-1) K-1, which is 1.5 times that of pure copper (ca. 400 W m(-1) K-1). Graphic High thermal conductivity Cu/diamond composites were fabricated by electrodeposition under a potentiostatic condition without the evolution of hydrogen gas.ArticleJOURNAL OF APPLIED ELECTROCHEMISTRY. 50(5):631-638 (2020)journal articl

Fabrication of high thermal conductivity Cu/diamond composites at ambient temperature and pressure

High thermal conductivity Cu/diamond composites were produced at ambient temperature and pressure using an electrodeposition technique, employing various diamond particle sizes in the range of 10 to 230 mu m. The microstructures of the resulting composites were analyzed by scanning electron microscopy and their thermal conductivities were assessed using a Xenon flash instrument. The theoretical thermal conductivities of these materials were calculated based on the Hasselman-Johnson equation and compared with the experimentally determined values. The Cu/diamond composites produced in this work were found to exhibit compact textures without any gaps between the Cu matrix and the diamond particles, and the experimental thermal conductivities were in good agreement with the theoretical values. The specimen containing 61 vol.% of 230 mu m diameter diamond particles had the highest conductivity of 662 W K-1 m(-1), which is 1.6 times that of pure Cu (ca. 400 W K-1 m(-1)). (C) 2019 Author(s).ArticleAIP ADVANCES. 9(8):085309 (2019)journal articl

Effect of Transition Elements upon the Nucleation and the Morphology of Magnetite in Silicate Melts of Basaltic Composition

Effects of transition elements, Ti, Cr and Cu upon the nucleation and morphology of mag-netite in silicate melts of basaltic compositon were examined. Crystallization of magnetite was carried out at △T= — 10°C in the atmospheric condition. Quenched products are composed of magnetite, (plagi-oclase) and silicate glass. Examinations of the morphology of magnetite show that an addition of Ti and Cu with Keff 1, has a definite effect to decrease grain size and to increase the number of crystals. The results obtained were discussed in relation to σ*, σ** and Keff

MEATabolomics: Muscle and Meat Metabolomics in Domestic Animals

In the past decades, metabolomics has been used to comprehensively understand a variety of food materials for improvement and assessment of food quality. Farm animal skeletal muscles and meat are one of the major targets of metabolomics for the characterization of meat and the exploration of biomarkers in the production system. For identification of potential biomarkers to control meat quality, studies of animal muscles and meat with metabolomics (MEATabolomics) has been conducted in combination with analyses of meat quality traits, focusing on specific factors associated with animal genetic background and sensory scores, or conditions in feeding system and treatments of meat in the processes such as postmortem storage, processing, and hygiene control. Currently, most of MEATabolomics approaches combine separation techniques (gas or liquid chromatography, and capillary electrophoresis)–mass spectrometry (MS) or nuclear magnetic resonance (NMR) approaches with the downstream multivariate analyses, depending on the polarity and/or hydrophobicity of the targeted metabolites. Studies employing these approaches provide useful information to monitor meat quality traits efficiently and to understand the genetic background and production system of animals behind the meat quality. MEATabolomics is expected to improve the knowledge and methodologies in animal breeding and feeding, meat storage and processing, and prediction of meat quality

MEATabolomics: Muscle and Meat Metabolomics in Domestic Animals

In the past decades, metabolomics has been used to comprehensively understand a variety of food materials for improvement and assessment of food quality. Farm animal skeletal muscles and meat are one of the major targets of metabolomics for the characterization of meat and the exploration of biomarkers in the production system. For identification of potential biomarkers to control meat quality, studies of animal muscles and meat with metabolomics (MEATabolomics) has been conducted in combination with analyses of meat quality traits, focusing on specific factors associated with animal genetic background and sensory scores, or conditions in feeding system and treatments of meat in the processes such as postmortem storage, processing, and hygiene control. Currently, most of MEATabolomics approaches combine separation techniques (gas or liquid chromatography, and capillary electrophoresis)–mass spectrometry (MS) or nuclear magnetic resonance (NMR) approaches with the downstream multivariate analyses, depending on the polarity and/or hydrophobicity of the targeted metabolites. Studies employing these approaches provide useful information to monitor meat quality traits efficiently and to understand the genetic background and production system of animals behind the meat quality. MEATabolomics is expected to improve the knowledge and methodologies in animal breeding and feeding, meat storage and processing, and prediction of meat quality

Computer-Assisted Laboratory Diagnosis and Its Clinical Usefulness

Clinical diagnosis based solely on the interpretation of laboratory tests without information regarding patient\u27s morbid history and physical examination is now possible when properly selected tests are set in combination and carried out for the definite purposes of (1) appraisal of the patient\u27s general condition, (2) assessment of hepatic, renal and pancreatic dysfunction, and (3) guessing the names of the patient\u27s possible diseases. Interpretation of test results can now be carried out quickly and very efficiently by means of a computer. This is computer-assisted laboratory diagnosis or CALD. It was in 1970, 15 years ago, that the first primitive trial of such a system was carried out in Ube, Yamaguchi. Since then this system of CALD has evolved to the level that its use has become a part of daily routine in the Departments of Clinical Pathology of Kawasaki Medical School, Kurashiki, and Yamaguchi University School of Medicine, Ube. It was described to the members of the Korean Society of Clinical Pathologists in their general meeting held in Taegu in 1985. Recently a team in the Department of Clinical Pathology of Tokai University Medical School in Isehara, Kanagawa Prefecture, was successful in developing another type of CALD. In the United States although trials of CALD were started in the 1970\u27s, development has not been so rapid. At present, only a few laboratories are employing CALD. Aspects of CALD development in Japan and the USA will be described very briefly in the latter part of this article

Proton Spin Relaxation Induced by Quantum Tunneling in Fe8 Molecular Nanomagnet

The spin-lattice relaxation rate $T_{1}^{-1}$ and NMR spectra of $^1$H in single crystal molecular magnets of Fe8 have been measured down to 15 mK. The relaxation rate $T_1^{-1}$ shows a strong temperature dependence down to 400 mK. The relaxation is well explained in terms of the thermal transition of the iron state between the discreet energy levels of the total spin S=10. The relaxation time $T_1$ becomes temperature independent below 300 mK and is longer than 100 s. In this temperature region stepwise recovery of the $^1$H-NMR signal after saturation was observed depending on the return field of the sweep field. This phenomenon is attributed to resonant quantum tunneling at the fields where levels cross and is discussed in terms of the Landau-Zener transition.Comment: 13 pages, 5 figure