10 research outputs found
Large-strain-induced magnetic properties of Co electrodeposited on nanoporous Au
Nanostructured Co with large lattice extension and contraction was produced by electrodepositing Co on nanoporous Au. The Co deposited showed a low magnetic saturation of 76 emu/g and a high coercivity of 462 Oe. First-principles calculations showed that the magnetic moment of a Co atom is significantly decreased by lattice contraction. Therefore, the noteworthy magnetic properties of the Co deposited are attributed to the large lattice strain. Also, molecular dynamics simulation showed that the lattice extension and contraction of about 10% are generated in the overall Co crystal. This is in agreement with the experimental results of HRTEM observation. The constraint of the movement of Co atoms by the concave structure of nanoporous Au leads to a wide spread of large strain region
Catalytic decoloration of methyl orange solution by nanoporous metals
Nanoporous Au exhibits catalytic degradation of methyl orange (MO) solution while its counterpart, bulk Au, does not. Other nanoporous metals such as Pd and Ni also exhibited the catalytic MO degradation. Because the degradation occurred under dark conditions, it is clearly distinguished from photocatalytic degradation conventionally observed in TiO₂ and ZnO
Preparation of Nanoporous Ruthenium Catalyst and Its CO Oxidation Characteristics
Anodic polarization measurements for various ruthenium (Ru) alloys revealed that hexagonal close-packed nanoporous Ru (np-Ru) can be fabricated by dealloying or selective dissolution of manganese (Mn) from Ru–Mn alloy. The pore size and specific surface area of fabricated np-Ru were 3 nm and 51.5 m²g⁻¹, respectively. An electron diffraction pattern suggested a polycrystalline nature of the fabricated np-Ru, which is perhaps due to the change in the crystal structure during dealloying. The oxidation of carbon monoxide (CO) was efficiently catalyzed by the np-Ru. The activation energy was 82 kJ mol⁻¹ which is comparable to that of the polycrystalline RuO₂/Ru catalyst. The present np-Ru is a novel candidate as a recoverable Ru catalyst
Magnetism of fcc/fcc, hcp/hcp twin and fcc/hcp twin-like boundaries in cobalt
The magnetic moments of the fcc/fcc, hcp/hcp twin and fcc/hcp twin-like boundaries in cobalt were investigated by first-principles calculations based on density functional theory. The magnetic moments in fcc/fcc were larger than those of the bulk fcc, while the variations in the magnetic moment were complicated in hcp/hcp and fcc/hcp. The magnetovolume effect on the magnetic moment at the twin(-like) boundaries was investigated in terms of the local average atomic distance and the average deviation from equilibrium; however, the complicated variations in the magnetic moment could not be explained from the magnetovolume effect. Next, the narrowing (or broadening) of the partial density of states (PDOS) width of 3d orbitals, the number of occupied states for the spin-down channel, and the PDOS around the Fermi level were investigated. The entire variation in the magnetic moment at the twin(-like) boundaries could be understood in terms of these factors. Charge transfer occurred in hcp/hcp. In this case, the contributions of 4s and 4p electrons to the variation in the magnetic moment were relatively large
Visible-light photocatalysis of ZnO deposited on nanoporous Au
ZnO deposited on nanoporous Au showed photocatalytic decomposition toward methyl orange under visible light, unlike ZnO sputtered on flat Au without a nanoporous structure. First-principles calculations suggested that the surface lattice disorder in nanoporous Au induced a band gap narrowing and a large built-in electric field in the adjacent ZnO, resulting in the visible-light photocatalytic response
Sema3E-PlexinD1 signaling selectively suppresses disoriented angiogenesis in ischemic retinopathy in mice
A nationwide multi-institutional retrospective study to identify prognostic factors and develop a graded prognostic assessment system for patients with brain metastases from uterine corpus and cervical cancer
Abstract Background The prevalence of brain metastases (BM) from uterine cancer has recently increased because of the improvement of overall survival (OS) of patients with uterine cancer due to its early detection and improved local control as a result of new effective treatments. However, little information is available regarding their clinical characteristics and prognosis, because oncologists have encountered BM from uterine cancer on rare occasions. Methods Records from 81 patients with uterine BM were collected from 10 institutes in Japan. These were used in a multi-institutional study to identify prognostic factors and develop a graded prognostic assessment (GPA) for patients with BM from uterine cancer. Results Median OS after the development of BM was 7 months (95% confidence interval, 4 to 10 months). Multivariate analysis revealed that there were survival differences according to the existence of extracranial metastases and number of BM. In the present uterine-GPA, a score of 0 was assigned to those patients with ≥5 BM and extracranial metastasis, a score of 2 was assigned to those patients with one to four BM or without extracranial metastasis, and a score of 4 was assigned to those patients with one to four BM and without extracranial metastasis. The median OS for patients with a uterine-GPA scores of 0, 2, and 4 was 3, 7, and 22 months, respectively. A survival analysis confirmed the presence of statistically significant differences between these groups (p < 0.05). The results were validated by data obtained from the National Report of Brain Tumor Registry of Japan. Conclusion Uterine GPA incorporates two simple clinical parameters of high prognostic significance and can be used to predict the expected survival times in patients with BM from uterine cancer. Its use may help in determining an appropriate treatment for individual patients with BM