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The Japanese national project started on standardization of the test method of the DC critical current of superconducting cables. A round robin test of critical current measurement is carried out to survey underlying problems for the standardization. The sample cables are made of Bi-2223 tapes and the inner core conductor has two layers and the outer shield conductor is composed of a single layer. The diameter of the shield layer is about 40 mm and the length of the cable is 2.00 m. The critical current was determined by the electric field criterion of 1 μV/cm. The n value is also measured for the inner core and the outer shield conductor. Three institutes participated in the test for two sample cables. The obtained experimental relative standard deviation for the critical current at 77.30 K is in the range of 0.2 to 1.3%, and is sufficiently small. Hence, it can be said that the present method that is widely used is suitable as a standard test method. On the other hand, the experimental relative standard deviation of the value is in the range of 2.8 to 18.6%, which is relatively large. This is caused by the measurements done at different temperatures.

A large-scale demonstration test of a triaxial high-temperature superconducting (HTS) cable for a practical cable system was performed in a chemical plant of a private company. The 200 m-long HTS (REBCO: REBa2Cu3O7-δ) triaxial cable, which was manufactured by connecting 3 cables using 2 joints via a snake-shaped layout, was laid approximately 5 m higher than ground level, and the cable was cryocooled by circulating liquid nitrogen. For the preverification test, the rise-up test of the liquid nitrogen and the development of technology for bending the cable, joining it, as well as laying and installing it, were conducted. No leakage of liquid nitrogen at the terminal due to damage caused by heat shock or liquid nitrogen drop impact was observed. The pressure required for the liquid nitrogen to achieve a 5 m height was from 27.5 to 33 kPa, which is in good agreement with the calculated pressure of 33.6 kPa. The cooling rate was well controlled, and the desired level of 4 K/h was achieved. The economic challenges and methods of achieving market penetration were also discussed. The goal was to realize a superconducting cable for practical applications, and it was thought that the energy and costs necessary for cryocooling could be drastically reduced by using the existing cold system in the plant. In this way, it is expected HTS cables can achieve low costs and high energy-saving effects and penetrate markets in the future.

A new ternary layered pnictide, Li1−xSn2+xP2, was synthesized by a solid-state reaction and its properties were examined to explore its potential as a multifunctional material. The compound crystallizes in a layered structure in the Rm space group (no. 166) with buckled honeycomb Sn–P layers separated by mixed-occupation Li/Sn layers. Crystal structure analysis by synchrotron X-ray diffraction showed that the substitution degree of Li by Sn is x = 0.38. The local ordering of Li/Sn occupation was demonstrated using 31P nuclear magnetic resonance analysis. The thermal and electrical transport properties are significantly affected by this local ordering. The lattice thermal conductivity of Li1−xSn2+xP2 was found to be relatively low (1.2 W m−1 K−1 at 525 K). The room-temperature electrical resistivity of Li1−xSn2+xP2 was found to be 0.3–0.4 mΩ cm and metallic conductivity was observed down to 0.5 K. First-principles calculations demonstrated that the electronic structure and Fermi energy of Li1−xSn2+xP2 are significantly dependent upon x. Moreover, the electronic structure of Li1−xSn2+xP2 is different from that of the related compound NaSn2As2, which shows a superconducting transition. Electrochemical measurements using a single-particle technique demonstrated the activity of Li1−xSn2+xP2 as an anode material for rechargeable Li-ion batteries.

Bioleaching of arsenic (As)-rich, so-called “dirty” concentrates can produce additional Cu value from the flotation waste while simultaneously releasing toxic As. This study bioleached three such concentrates of varying pyrite/enargite ratios ([Py]/[Ena] = 0.7, 1.3 and 2.4) at a pulp density of 20%. The dissolution behavior of Cu and As in relation to the solution redox potential (Eh) was studied with and without activated carbon (AC) as a potential Eh-controlling catalyst. At this high pulp density, Eh was naturally suppressed, without a need for AC dosing, to

Lysozyme chloride is a bactericidal substance that is included as an active ingredient in many medicines and quasi-drugs. We experienced a case of anaphylactic reaction caused by deodorant spray-containing lysozyme chloride.The patient was a 10-year-old girl who had an egg allergy. She visited an emergency department because of urticaria, wheezing, dyspnea, and pallor after she used deodorant spray that contained lysozyme chloride derived from hen's egg white. Results for deodorant spray and lysozyme chloride were positive in both skin prick tests and basophil activation tests. According to the medical history and the results, her condition was diagnosed as an anaphylactic reaction to lysozyme chloride in the deodorant spray.Although ingredient labelling is obligatory for lysozyme chloride in quasi-drugs, lysozyme chloride is not often described to be derived from egg white. It is important to alert patients with egg allergy to avoid lysozyme chloride-containing products.

Sodium metabisulfite (MBS) was used in this study for selective flotation of chalcopyrite and molybdenite. Microflotation tests of single and mixed minerals were performed to assess the floatability of chalcopyrite and molybdenite. The results of microflotation of single minerals showed that MBS treatment significantly depressed the floatability of chalcopyrite and slightly reduced the floatability of molybdenite. The results of microflotation of mixed minerals demonstrated that the MBS treatment could be used as a selective chalcopyrite depressant in the selective flotation of chalcopyrite and molybdenite. Furthermore, the addition of diesel oil or kerosene could significantly improve the separation efficiency of selective flotation of chalcopyrite and molybdenite using MBS treatment. A mechanism based on X-ray photoelectron spectroscopy analysis results is proposed in this study to explain the selective depressing effect of MBS on the flotation of chalcopyrite and molybdenite.

The Ising magnet $\mathrm{Sm}{\mathrm{Pt}}_{2}{\mathrm{Si}}_{2}$ undergoes an antiferromagnetic (AFM) transition at ${T}_{\mathrm{N}1}$ = 5.6 K, but the magnetic moments of some Sm ions remain disordered even below ${T}_{\mathrm{N}1}$. Here, we report the results of measurements of thermal expansion, magnetostriction, and dc magnetization of $\mathrm{Sm}{\mathrm{Pt}}_{2}{\mathrm{Si}}_{2}$ in the temperature range from 0.26 to 7 K. The magnetization and thermal expansion results show clear irreversible phenomena at temperatures below ${T}_{\mathrm{g}}\phantom{\rule{4pt}{0ex}}\ensuremath{\approx}$ 2.4 K. These results suggest that the partially disordered state of the Sm ions becomes a cluster spin glass below ${T}_{\mathrm{g}}$ and coexists with the AFM long-range order. However, unlike the conventional coexistence of spin glass and antiferromagnetism, the isothermal magnetization process at 0.26 K shows a hysteresis curve with almost no remanent magnetization. This observation suggests that the cluster spin glass state is an unusual state with a short relaxation time at zero field.

We propose an efficient way of increasing the entropy of mixing in high-entropy-alloy-type compounds, which can be achieved by multi-site alloying. As an example of this concept, we report the synthesis and observation of polycrystalline samples of new high-entropy-alloy-type metal chalcogenides (Ag,In,Pb,Bi)Te1-xSex (x = 0.0, 0.25, and 0.5) with a NaCl-type structure. The samples were synthesized using high pressure synthesis. Superconductivity with transition temperatures of 2.7, 2.5, and 2.0 K was observed with x = 0.0, 0.25, and 0.5, respectively. To investigate the multi-site alloying effect on the entropy of mixing (ΔSmix) for the examined samples, we calculated the total ΔSmix for two crystallographic sites. For the samples with x = 0.25 and 0.5, ΔSmix reaches 1.89R and 2.00R, respectively, which exceed the ΔSmix of 1.79R for a simple (single-site) high-entropy alloy containing six different elements.

The copper ore in Chilean copper porphyry deposits is often associated with molybdenum minerals. This copper–molybdenum (Cu–Mo) sulfide ore is generally mined from various locations in the mining site, thus, the mineral composition, oxidation degree, mineral particle size, and grade vary. Therefore, in the mining operation, it is common to blend the ores mined from various spots and then process them using flotation. In this study, the floatability of five types of Cu–Mo ores and the blending of these ores in seawater was investigated. The oxidation degree of these Cu–Mo ores was evaluated, and the correlation between flotation recovery and oxidation degree is presented. Furthermore, the flotation kinetics of each Cu–Mo ore were calculated based on a mineralogical analysis using mineral liberation analysis (MLA). A mineralogical prediction model was proposed to estimate the flotation behavior of blended Cu–Mo ore as a function of the flotation behavior of each Cu–Mo ore. The flotation results show that the recovery of copper and molybdenum decreased with the increasing copper oxidization degree. In addition, the recovery of blended ore can be predicted via the flotation rate equation, using the maximum recovery (Rmax) and flotation rate coefficient (k) determined from the flotation rate analysis of each ore before blending. It was found that Rmax and k of the respective minerals slightly decreased with increasing the degree of copper oxidation. Moreover, Rmax varied greatly depending on the mineral species. The total copper and molybdenum recovery were strongly affected by the degree of copper oxidation as the mineral fraction in the ore varied greatly depending upon the degree of oxidation.

OBJECTIVES: Thiamine acts as a coenzyme (prosthetic group) after converting to thiamine pyrophosphate in crucial metabolic enzymes of pyruvate dehydrogenase, α-ketoglutarate dehydrogenase and transketolase. Theoretically, thiamine should not be consumed by an increase in the number of substrates for those enzymes. However, thiamine is often described to be consumed by excessive carbohydrate intake. Such a possible misunderstanding is assessed in the relevant literature. METHODS: The original paper (Elmadfa, et al. Int J Vitam Nutr Res 2001), which seems to mislead the reader into considering an increase in thiamine requirement for excessive carbohydrate intake, and the relevant papers were reviewed. RESULTS: The original paper demonstrated that increases in carbohydrate intake from 55% to 65% and 75% of total energy caused decreases in plasma and urine concentrations of thiamine, while erythrocyte transketolase activity remained unchanged. This seems to misleadingly support the idea that excessive carbohydrate intake increases the thiamine requirement for carbohydrate metabolism. It could be interpreted as the decreases of thiamine concentrations were observed only during an adaptation period. It was reported that diabetic patients had low plasma thiamine levels in association with increased renal clearance and fractional excretion of thiamine, without a decrease in erythrocyte transketolase activity (Thornalley, et al. Diabetologia 2007). As a similar case of possible misinterpretation, a case report (Watson, et al. Ir J Med Sci 1981) demonstrated that glucose loading precipitated thiamine deficiency in malnourished patients with latent thiamine deficiency. CONCLUSIONS: From the relevant literature, it is inferred that excessive carbohydrate intake in people without hyperglycemia could lead to a small increase, if any, in urinary thiamine excretion, but not to an increase in thiamine requirement for glucose metabolism. Even in the academic field, it seems that thiamine is often misunderstood to be consumed by excessive carbohydrate intake. FUNDING SOURCES: None.

Overcoming the slow-leaching kinetics of refractory primary copper sulfides is crucial to secure future copper sources. Here, the effect of carbon was investigated as a catalyst for a bioleaching reaction. First, the mechanism of carbon-assisted bioleaching was elucidated using the model chalcopyrite mineral, under specified low-redox potentials, by considering the concept of Enormal. The carbon catalyst effectively controlled the Eh level in bioleaching liquors, which would otherwise exceed its optimal range (0 ≤ Enormal ≤ 1) due to active regeneration of Fe3+ by microbes. Additionally, Enormal of ~0.3 was shown to maximize the carbon-assisted bioleaching of the model chalcopyrite mineral. Secondly, carbon-assisted bioleaching was tested for three types of chalcopyrite/enargite-bearing complex concentrates. A trend was found that the optimal Eh level for a maximum Cu solubilization increases in response to the decreasing chalcopyrite/enargite ratio in the concentrate: When chalcopyrite dominates over enargite, the optimal Eh was found to satisfy 0 ≤ Enormal ≤ 1. As enargite becomes more abundant than chalcopyrite, the optimal Eh for the greatest Cu dissolution was shifted to higher values. Overall, modifying the Eh level by adjusting AC doses to maximize Cu solubilization from the concentrate of complex mineralogy was shown to be useful.

Sequential treatment was applied to carbonaceous Au-Ag-bearing ore concentrate to maximize the Au and Ag recovery. In the preliminary test, the present carbonaceous ore had well liberated and exposed type of gold grains, which are not refractory, but included mainly three types of Ag presented as electrum, hessite (Ag2Te) and Ag-bearing other minerals. Au recovery was ∼100% without any treatment, meanwhile Ag recovery was only 33.3%. The sequential treatment comprises two oxidation steps: (a) mixed culture of iron- and sulfur-oxidizing microorganisms at pH 1.2, followed by (b) cell-free spent medium (CFSM) at pH 4.0 from a white rot-fungus, Phanerochaete chrysosporium, which includes lignin-degrading enzymes. As a result, Ag recovery was 55.5% after the first step and greatly improved to ∼100%, including the dissolved Ag+ concentration in the first step of acid treatment. Although the acidophilic iron-oxidizing microorganisms were inhibited by dissolved Ag+ and Cd2+ ions, the strong acidic conditions dissolved hessite and Ag-bearing oxide minerals. However, the remaining carbonaceous matter acted to sorb Ag(CN)2− in cyanidation, causing the recovery loss. In the next step the lignin-degrading enzymes degraded carbonaceous matter in the ore. This step is necessary to avoid the adsorption of Ag(CN)2− on graphitic carbonaceous matter, leading a mostly perfect recovery of the remaining Ag in the solid residues, without necessity of alkaline washing. The sequential treatment including enzymatic lignin-degrading process was also effective in carbonaceous silver ore avoiding the emission of air pollutants.

A new ternary layered pnictide, Li1-xSn2+xP2, was synthesized by a solid-state reaction and its properties were examined to explore its potential as a multifunctional material. The compound crystallizes in a layered structure in the R-3m space group with buckled honeycomb Sn-P layers separated by mixed-occupation Li/Sn layers. Crystal structure analysis using synchrotron X-ray diffraction showed that the substitution degree of Li by Sn (x) is approximately 0.3. Local ordering of Li/Sn occupation was demonstrated using 31P nuclear magnetic resonance analysis. The lattice thermal conductivity of Li1-xSn2+xP2 was found to be relatively low (1.2 Wm−1K−1 at 525 K). The room-temperature electrical resistivity of Li1-xSn2+xP2 was found to be 0.3-0.4 mohm cm and metallic conductivity was observed down to 0.5 K. First-principles calculations demonstrated that the electronic structure and Fermi energy of Li1-xSn2+xP2 are significantly dependent upon x. Electrochemical measurements using a single-particle technique demonstrated the activity of Li1-xSn2+xP2 as an anode material for rechargeable Li-ion batteries.