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Electrochemical fabrication of nanowires poly (Indole-6-carboxylic acid) adorned with nanorod MnO2 for evaluation of its capacitive properties
No full textA poly(indole-6-carboxy acid) nanowire composite with & beta;-MnO2 nanorod (6-PICA|& beta;-MnO2-NRs) was prepared by an electrochemical method and hydrothermal. The incorporation of & beta;-MnO2-NRs and the formation of 6-PICA nanowires are verified by SEM, TEM, Raman, powder XRD, and XPS, where the nanowires perform as an electroactive material and also as an environment to disperse the & beta;-MnO2 nanorods, at different concentrations. The study as a supercapacitor material shows that the specific capacitance of 6-PICA|& beta;-MnO2-NRs is 61.35 mFcm  2, higher than that of 6-PICA (43.01 mFcm  2) deposited on the ITO conductive glass electrode. These results indicate that the presence of pure phase & beta;-MnO2 in the form of nanostructure enhances the specific capacitance and ion diffusion in the charge-discharge process of 6-PICA at higher current densities without losing significant stability after 1000 cycles.AMRR thanks ANID - FONDECYT No. 11190995 and No. 1230426, and JC thanks the support from Unidad de Equipamiento Cientifico MAINI-UCN through Powder X -Ray Diffraction data (DRX-FIC Regional EQU 25 Conicyt 2010). At Vicerrectoria de Investigacion y Desarrollo Tecnologico (VRIDT-UCN), Direccion de Investigacion y Analisis de la Produccion Cientifica (DIAPC-UCN) of the Universidad Catolica del Norte, Chile (Proyecto de Iniciacion a la investigacion -VRIDT-UCN), and Partially funded by the Lithium I + D + i Center of the Universidad Catolica del Norte (lithium.ucn.cl)
Spin-lattice-dynamics analysis of magnetic properties of iron under compression
No full textCompression of a magnetic material leads to a change in its magnetic properties. We examine this effect using spin-lattice dynamics for the special case of bcc-Fe, using both single- and poly-crystalline Fe and a bicontinuous nanofoam structure. We find that during the elastic phase of compression, the magnetization increases due to a higher population of the nearest-neighbor shell of atoms and the resulting higher exchange interaction of neighboring spins. In contrast, in the plastic phase of compression, the magnetization sinks, as defects are created, increasing the disorder and typically decreasing the average atom coordination number. The effects are more pronounced in single crystals than in polycrystals, since the presence of defects in the form of grain boundaries counteracts the increase in magnetization during the elastic phase of compression. Also, the effects are more pronounced at temperatures close to the Curie temperature than at room temperature. In nanofoams, the effect of compression is minor since compression proceeds more by void reduction and filament bending-with negligible effect on magnetization-than by strain within the ligaments. These findings will prove useful for tailoring magnetization under strain by introducing plasticity.Open Access funding enabled and organized by Projekt DEAL. GDS, DT and EMB thank support from a SIIP-UNCUYO-2022-2023 grant, from PICTO-UUMM-2019-00048 and from PIP 2021-2023 11220200102578CO. RM acknowledges support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)-project number 268565370-TRR 173 Spin+X (project A06). Open Access funding enabled and organized by Projekt DEAL
Assessment of Bio-Compounds Content, Antioxidant Activity, and Neuroprotective Effect of Red Cabbage (Brassica oleracea var. Capitata rubra) Processed by Convective Drying at Different Temperatures
No full textParkinson's disease (PD) is the second most common neurodegenerative disorder, and no efficient therapy able to cure or slow down PD is available. In this study, dehydrated red cabbage was evaluated as a novel source of bio-compounds with neuroprotective capacity. Convective drying was carried out at different temperatures. Total phenolics (TPC), flavonoids (TFC), anthocyanins (TAC), and glucosinolates (TGC) were determined using spectrophotometry, amino acid profile by LC-DAD and fatty acid profile by GC-FID. Phenolic characterization was determined by liquid chromatography-high-resolution mass spectrometry. Cytotoxicity and neuroprotection assays were evaluated in SH-SY5Y human cells, observing the effect on preformed fibrils of alpha-synuclein. Drying kinetic confirmed a shorter processing time with temperature increase. A high concentration of bio-compounds was observed, especially at 90 C-degrees, with TPC = 1544.04 +/- 11.4 mg GAE/100 g, TFC = 690.87 +/- 4.0 mg QE/100 g and TGC = 5244.9 +/- 260.2 mu mol SngE/100 g. TAC degraded with temperature. Glutamic acid and arginine were predominant. Fatty acid profiles were relatively stable and were found to be mostly C18:3n3. The neochlorogenic acid was predominant. The extracts had no cytotoxicity and showed a neuroprotective effect at 24 h testing, which can extend in some cases to 48 h. The present findings underpin the use of red cabbage as a functional food ingredient.This research was supported by the Agencia Nacional de Investigacion y Desarrollo, ANID-Chile, through funds provided to Project FONDECYT 1210124
Editorial: Physiological, biochemical and molecular approaches in response to abiotic stresses in plants
No full textSin resumen.This work was supported by grants from the Chilean ANID/ACT210007 (AA); and Universidad Mayor (grant no. I-2022006; AA)
Green Cover And Socioemotional And Academic Outcomes Of School Age Children. The Case Of Santiago, Chile
No full textMapping Firms Adaptive Profiles: The Role Of Experiences And Risk Perception In The Aquaculture Industry
No full textTeaching Of Educational Content Expressing Mapuche Values To Children In Initial Education In La Araucania Region, Chile
No full textStable Isotope Composition (C And N) Of Vegetation In Subtropical Andes: Piedmont 'Anomaly' And Its Implications For Paleo (Ecology) And Human Diet Reconstruction
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