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1.
ACS Appl Mater Interfaces ; 16(40): 53631-53642, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39322220

RESUMO

All-solid-state fluoride batteries have the potential to achieve energy densities significantly higher than those of lithium-ion batteries. A common cathode material for fluoride batteries is Cu. Cu has a low polarization, but its rapid capacity degradation due to grain growth and subsequent delamination from the solid-state electrolyte are critical issues. To enhance the performance of Cu-based cathodes in all-solid-state fluoride batteries, we explore alloying of Cu with Ni to create metastable solid solution phases (CuxNi1-x with x = 0, 0.32, 0.52, 0.72, 0.89, and 1.0). Compared to Cu, Ni has a higher polarization but exhibits superior capacity retention. The Cu0.72Ni0.28 alloy demonstrates a polarization as low as Cu, but it has a significantly improved capacity retention, which is comparable to Ni. Transmission electron microscopy observations demonstrate that the thin Ni-rich region formed near the interface inhibits Cu grain growth and delamination from the LaF3 electrolyte. By incorporating an appropriate amount of Ni into Cu, Cu-Ni alloy films combine the advantages of both metals, improving the performance of fluoride batteries.

2.
Planta ; 249(6): 1921-1947, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30891648

RESUMO

MAIN CONCLUSION: Among seaweed groups, brown algae had characteristically high concentrations of mannitol, and green algae were characterised by fructose. In red algae, metabolite profiles of individual species should be evaluated. Seaweeds are metabolically different from terrestrial plants. However, general metabolite profiles of the three major seaweed groups, the brown, red, and green algae, and the effect of various extraction methods on metabolite profiling results have not been comprehensively explored. In this study, we evaluated the water-soluble metabolites in four brown, five red, and two green algae species collected from two sites in northern Japan, located in the Sea of Japan and the Pacific Ocean. Freeze-dried seaweed samples were processed by methanol-water extraction with or without chloroform and analysed by capillary electrophoresis- and liquid chromatography-mass spectrometry for metabolite characterisation. The metabolite concentration profiles showed distinctive characteristic depends on species and taxonomic groups, whereas the extraction methods did not have a significant effect. Taxonomic differences between the various seaweed metabolite profiles were well defined using only sugar metabolites but no other major compound types. Mannitol was the main sugar metabolites in brown algae, whereas fructose, sucrose, and glucose were found at high concentrations in green algae. In red algae, individual species had some characteristic metabolites, such as sorbitol in Pyropia pseudolinearis and panose in Dasya sessilis. The metabolite profiles generated in this study will be a resource and provide guidance for nutraceutical research studies because the information about metabolites in seaweeds is still very limited compared to that of terrestrial plants.


Assuntos
Clorófitas/metabolismo , Metaboloma , Phaeophyceae/metabolismo , Rodófitas/metabolismo , Alga Marinha/metabolismo , Análise por Conglomerados , Frutose/metabolismo , Manitol/metabolismo , Especificidade da Espécie
3.
Chemistry ; 22(17): 5924-36, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-26970337

RESUMO

Recently, it was shown that µ-oxo-µ-peroxodiiron(III) is converted to high-spin µ-oxodioxodiiron(IV) through O-O bond scission. Herein, the formation and high reactivity of the anti-dioxo form of high-spin µ-oxodioxodiiron(IV) as the active oxidant are demonstrated on the basis of resonance Raman and electronic-absorption spectral changes, detailed kinetic studies, DFT calculations, activation parameters, kinetic isotope effects (KIE), and catalytic oxidation of alkanes. Decay of µ-oxodioxodiiron(IV) was greatly accelerated on addition of substrate. The reactivity order of substrates is toluene

4.
Environ Monit Assess ; 184(7): 4501-15, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21830065

RESUMO

This study investigated the arsenic (As) level in groundwater, and the characteristics of aquifer sediment as related to the occurrence of As in groundwater in Hanam, Vietnam. The deposition and transport of As-containing substances through rivers were also examined. Arsenic concentrations in 88% of the groundwater samples exceeded the As limit for drinking water based on the WHO standards. The dominating form of arsenic was As(III). The maximum total As content in bore core sediment was found in a peat horizon of the profiles and generally, elevated levels of As were also found in other organic matter-rich horizons. Total As contents of the bore core sediments were significantly correlated with crystalline iron oxide, silt and clay contents, suggesting that As in aquifer sediment was mainly associated with iron (hydr)oxides and clay mineral. In the groundwater, As concentration showed significant correlations with the total concentrations of Fe and HCO (3)(-). Significant correlations between HCl-extractable As and non-crystalline Fe oxide, total C, N, and S were also observed in the profiles. The results support the hypothesis that under favorable reductive conditions established by the degradation of organic matter, the dissolution of iron (hydr)oxides releases adsorbed As into the groundwater. The deposition of As in the sediments from the Red River were significantly higher than that in the Chau Giang River, suggesting that the Red River is the main source of As-containing substances deposited in the study area.


Assuntos
Arsênio/análise , Monitoramento Ambiental , Água Subterrânea/química , Poluentes Químicos da Água/análise , Adsorção , Ferro/química , Minerais/química , Rios/química , Solo/química , Vietnã , Poluição Química da Água/estatística & dados numéricos
5.
Environ Monit Assess ; 170(1-4): 301-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19936956

RESUMO

In this study, we attempted multivariate color profiling of soils over a land degradation gradient represented by dry evergreen forest (original vegetation), dry deciduous forest (moderately disturbed by fire), and bare ground (severely degraded) in Sakaerat, Thailand. The soils were sampled in a dry-to-wet seasonal transition. Values of the red-green-blue (RGB), cyan-magenta-yellow-key black (CMYK), L*a*b*, and hue-intensity-saturation (HIS) color models were determined using the digital software Adobe Photoshop. Land degradation produced significant variations (p<0.05) in R, C, Y, L*, a*, b*, S, and I values (p<0.05). The seasonal transition produced significant variations (p<0.05) in R, G, B, C, M, K, L*, b*, and I values. In discriminating the soils, the color models did not differ in discriminatory power, while discriminatory power was affected by seasonal changes. Most color variation patterns had nonlinear relationships with the intensity of the land degradation gradient, due to effects of fire that darkened the deciduous forest soil, masking the nature of the soil as the intermediate between the evergreen forest and the bare ground soils. Taking these findings into account, the utilization of color profiling of soils in land conservation and rehabilitation is discussed.


Assuntos
Conservação dos Recursos Naturais , Solo/química , Cor , Modelos Químicos , Estações do Ano , Solo/análise , Tailândia , Árvores , Tempo (Meteorologia)
6.
Neurosci Lett ; 321(3): 141-4, 2002 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-11880192

RESUMO

A serine protease neuropsin expressed in the hippocampus of adult brain has been implicated in synaptic plasticity. We report here that endogenous neuropsin was localized extracellularly in neuronal cell bodies and their neurites in mouse hippocampal cultures. Furthermore, we found that, in cultured mouse hippocampal neurons, recombinant neuropsin enhanced neurite projection from soma after 14 h of culture and neuronal aggregation with neurite fascicles at 48 h. This suggests that neuropsin is involved in neurite outgrowth and fasciculation during the development of the nervous system.


Assuntos
Envelhecimento/metabolismo , Diferenciação Celular/fisiologia , Matriz Extracelular/enzimologia , Hipocampo/enzimologia , Hipocampo/crescimento & desenvolvimento , Calicreínas , Neuritos/enzimologia , Serina Endopeptidases/metabolismo , Animais , Agregação Celular/efeitos dos fármacos , Agregação Celular/fisiologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Matriz Extracelular/efeitos dos fármacos , Hipocampo/citologia , Imuno-Histoquímica , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/ultraestrutura , Proteínas Recombinantes/farmacologia , Serina Endopeptidases/farmacologia
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