We successfully prepared nanosized Fe-Co alloy powder directly by a thermal plasma process, although a small amount of unprocessed Co was observed in the X-ray diffraction results. The mean particle ...size was ∼90 nm. The processed alloy particles were found to be single crystals, as confirmed by EBSD measurement. When an initial mixed powder having an Fe: Co ratio of 70 : 30 was used as the starting material, the mean and standard deviation of the Co concentration were 26.7 at% and 3.0 at%, respectively. The saturation magnetization values were in agreement with the bulk value, indicating that this small amount of oxygen dose not greatly affect the value of mass magnetization. This research realized the first full magnetization of a bare FeCo nanosized powder without any reduction treatment.
•The FeCo alloy fine powder was prepared by thermal plasma process.•Processed FeCo nano particle was single crystal.•The concentration distribution of Fe and Co is quantitively evaluated.•The full magnetization for bare FeCo nanopowder was obtained.
This study investigated the usefulness of a novel inflammation-based prognostic system, named the COP-NLR (COmbination of Platelet count and Neutrophil to Lymphocyte Ratio), for predicting the ...postoperative survival of patients with colorectal cancer (CRC).
The COP-NLR was calculated on the basis of data obtained on the day of admission: patients with both an elevated platelet count (>30 × 10(4) mm(-3)) and an elevated NLR (>3) were allocated a score of 2, and patients showing one or neither were allocated a score of 1 or 0, respectively.
Four-hundred and eighty patients were enrolled. Multivariate analysis of clinical characteristics selected by univariate analysis showed that the COP-NLR (1, 2/0) (odds ratio, 0.464; 95% confidence interval, 0.267-0.807; P=0.007) had an association with cancer-specific survival, along with pathology, lymph node metastasis, the serum levels of carcinoembryonic antigen, C-reactive protein and albumin, and the Glasgow Prognostic Score. Kaplan-Meier analysis and log-rank test revealed that the COP-NLR was able to divide such patients into three independent groups (P<0.001).
The COP-NLR is considered to be a useful predictor of postoperative survival in patients with CRC.
•A Ni-Cu alloy nanopowder was prepared using induction thermal plasma (ITP) process.•The relationship between the composition and particle size was evaluated.•Alloy composition changed continuously ...depending on its location in the chamber.•The ITP process has high potential as a high-throughput powder process.
The composition of nanoparticles obtained by a thermal plasma process was quantitatively investigated using a Ni-Cu isomorphous alloy system. Specifically, a Ni-Cu alloy nanopowder with an average particle diameter of ~ 70 nm was prepared by the thermal plasma process and the particle composition was investigated. As the lattice constant follows the Vegard's law, a nanopowder with an average composition equivalent to the predefined composition was successfully obtained. According to the EDS analysis obtained from each particle, the standard deviation of composition distribution was 7.7 at% as a powder. The computational study indicated that each particle has a homogeneous composition because of the nanoparticle formation via nanodroplet and that a composition distribution of 1.05 at% is estimated in the powder. Further, the spatial composition distribution of the alloy powder in the reaction chamber was experimentally studied by trapping the powder at a certain location, and the results indicated that the composition distribution of the powder varied spatially.
A low oxygen induction thermal plasma (LO-ITP) system was developed and a cold-welding behavior of bare fine metallic aluminum powders prepared by the system developed here was observed. This ...behavior is suitable for a metal precursor for metal matrix composites (MMC) since fine and bare metal particles may contribute to obtaining a well-dispersed state and a high relative density respectively, which lead to the enhancement of the reinforcement of MMC properties. The electric conductivity of the aluminum green pellet compacted at 200 MPa reached 2.9 × 107 S/m, which is comparable to that of bulk aluminum, indicating that the cold welding was taken place since the surface contamination layer such as an oxide may be negligibly thin. Therefore, the powder obtained in this work is expected to be useful in enhancing the reinforcement of MMC properties.
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•A new low oxygen induction thermal plasma system was developed.•Bare fine metallic Al powders were successfully prepared.•The electric conductivity of the Al green pellet reached that of bulk Al.•This system can be used as a production process for fine bare metal powders.
Abstract
A systematic study on the formation and magnetic properties of Tsai-type 2/1 approximants in Ga–(Pd, Pt)–Tb alloys was conducted by replacing Pd with Pt in a previously reported ...antiferromagnetic Ga–Pd–Tb 2/1 approximant. Tsai-type 2/1 approximants were found to form quaternary Ga–(Pd, Pt)–Tb alloys as well as ternary Ga–Pt–Tb alloys. Magnetic susceptibility measurements indicated that the substitution of Pt for Pd in the 2/1 approximants resulted in a change in the magnetism from antiferromagnetic to spin-glass-like behavior.
Triple helix formation of procollagen occurs in the endoplasmic reticulum (ER) where the single-stranded α-chains of procollagen undergo extensive post-translational modifications. The modifications ...include prolyl 4- and 3-hydroxylations, lysyl hydroxylation, and following glycosylations. The modifications, especially prolyl 4-hydroxylation, enhance the thermal stability of the procollagen triple helix. Procollagen molecules are transported to the Golgi and secreted from the cell, after the triple helix is formed in the ER. In this study, we investigated the relationship between the thermal stability of the collagen triple helix and environmental temperature. We analyzed the number of collagen post-translational modifications and thermal melting temperature and α-chain composition of secreted type I collagen in zebrafish embryonic fibroblasts (ZF4) cultured at various temperatures (18, 23, 28, and 33 °C). The results revealed that thermal stability and other properties of collagen were almost constant when ZF4 cells were cultured below 28 °C. By contrast, at a higher temperature (33 °C), an increase in the number of post-translational modifications and a change in α-chain composition of type I collagen were observed; hence, the collagen acquired higher thermal stability. The results indicate that the thermal stability of collagen could be autonomously tuned according to the environmental temperature in poikilotherms.
In order to realize an anisotropic bulk nanocomposite (NC) magnet, anisotropic SmCo 5 powder and Fe nanopowder were prepared by a low oxygen powder metallurgy process. Single-phase SmCo 5 powder was ...obtained by an arc melting and jet milling process. Spherical Fe nanopowder with an average particle size of 98 nm was prepared by the low oxygen-induction thermal plasma (LO-ITP) process. Magnetic measurements showed the anisotropic behavior of the SmCo 5 powder and coercivity of 1 MA/m. The sintered SmCo 5 /Fe NC magnet displayed the nonlinear spring-back curves, indicating the exchange coupling effect in this NC magnet. Very thin Fe areas were observed between the SmCo 5 grains when non-oxidized Fe nanoparticles were added, and it is assumed that effective exchange coupling was induced in these ideal microstructures. This work proposed the potential of an anisotropic hard magnetic powder prepared by jet milling, and nano-sized soft magnetic particles were prepared by the LO-ITP process for improving the magnetic properties of the anisotropic NC bulk magnet.
A PTL routing method for large-scale SFQ logic circuits is proposed. In this method, a routing problem is solved in two steps; global routing and detailed routing. In the global routing, a routing ...region is split into rectangular subregions and paths connecting them are obtained. Wire length budgeting is introduced into the global routing for allocating sufficient amount of routing resources to each net considering wire length matching in the detailed routing. In the detailed routing, exact wiring routes are determined based on a solution of the global routing and wire length matching is performed at each subregion. The global routing with wire length budgeting is formulated and an algorithm for it is proposed. In the proposed global routing algorithm, initial routes are searched at first using the rip-up and reroute technique, and then, routing resource distribution is calculated by constructing a flow-graph and solving a max-flow problem. If distribution of routing resources fails, global route extension is conducted to allocate additional routing resources to nets. The routing resource distribution and the global route extension are repeated until sufficient resources are allocated to all nets. As a design example, a 16 bit Sklansky adder was designed using the proposed method. Wire length matching in detailed routing was succeeded and the target frequency of 50 GHz was achieved.
It was predicted that TbCu7-type Sm-Fe powder prepared by the low-temperature reduction-diffusion (LTRD) process using a Li-Ca reductant would contain no residual ɑ-Fe because this reductant would ...not produce the absorbed water that hinders the reaction between Sm and Fe by forming oxychlorides when molten salt is used as the reductant. Contrary to this expectation, a detailed microstructure analysis revealed that a residual phase of unreacted ɑ-Fe existed in some TbCu7-type Sm-Fe particles rather than as separate Fe particles. This residual ɑ-Fe phase was not located in the center of the Sm-Fe particles and was not detected in some Sm-Fe particles, suggesting that the reason for the residual ɑ-Fe phase is inhomogeneous diffusion of Sm into the Fe due to slow diffusion at low temperatures. Although this TbCu7-type Sm-Fe powder contained a small amount of unreacted ɑ-Fe phase, the magnetic properties of the nitride TbCu7-type Sm-Fe were also estimated.
•The possibility synthesizing single-phase TbCu7-type Sm-Fe powder was investigated.•The residual α-Fe phase was smaller than in the case using molten salts.•ɑ-Fe phases are not located in the center of some TbCu7-type Sm-Fe particles.•It is inferred that the reduced Sm was inhomogeneously diffused into the Fe.•The coercivity of the TbCu7-type Sm-Fe-N powder was estimated as Hc = 5.5 MA·m-1
•The low-oxygen induction thermal plasma (LO-ITP) process was developed.•Both stable and metastable phases of anisotropic Nd-Fe ultrafine particles were prepared.•Numerical calculations clarify the ...alloying mechanism during rapid cooling wherein Nd-Fe vapor solidifies.•The LO-ITP process paves the way to achieve a new-generation anisotropic permanent magnet.
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Both stable Th2Zn17-type and metastable TbCu7-type phases of anisotropic Nd-Fe ultrafine particles are prepared selectively by controlling the cooling rate using the low-oxygen induction thermal plasma (LO-ITP) process. The cooling rate is controlled by introducing the additional Ar gas at the end of the plasma flame. Moreover, numerical calculations based on a binary aerosol formation-growth model clarifies the alloying mechanism during rapid cooling wherein Nd-Fe vapor solidifies. The metastable Nd-Fe alloy ultrafine particle is formed in the cooling rate of 5 × 105 K/sec via the alloy droplet which is formed after the Fe and Nd vapors convert simultaneously into the liquid phase. The mean particle sizes of obtained ultrafine alloy powders without and with quenching are 76.3 ± 24.2 nm and 37.0 ± 12.5 nm, respectively. Electron microscopy observation reveals that the obtained particles are single crystalline. The Nd concentration of Nd-Fe particles shows a distribution in the range of 10.1–12.6 at%. X-ray diffraction and magnetic measurement demonstrate that the obtained particles are anisotropic and can be aligned by external magnetic field. Therefore, this process paves the way to achieve a new-generation anisotropic permanent magnet.
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