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排序方式: 共有463条查询结果,搜索用时 15 毫秒
71.
Mirhashemihaghighi S León B Pérez Vicente C Tirado JL Stoyanova R Yoncheva M Zhecheva E Sáez Puche R Arroyo EM Romero de Paz J 《Inorganic chemistry》2012,51(10):5554-5560
A promising group of inorganic salts recently emerged for the negative electrode of advanced lithium-ion batteries. Manganese carbonate combines low weight and significant lithium storage properties. Electron paramagnetic resonance (EPR) and magnetic measurements are used to study the environment of manganese ions during cycling in lithium test cells. To observe reversible lithium storage into manganese carbonate, preparation by a reverse micelles method is used. The resulting nanostructuration favors a capacitive lithium storage mechanism in manganese carbonate with good rate performance. Partial substitution of cobalt by manganese improves cycling efficiency at high rates. 相似文献
72.
Mary C. Salazar José L. Paz Antonio J. Hernández Carlos I Manzanares Eduardo V. Ludeña 《Theoretical chemistry accounts》2001,106(3):218-222
In the present contribution we report a study of the weakly bound van der Waals N2–He molecule in the framework of the supermolecule approach by means of the PWPW and mPW1PW exchange–correlation functionals,
using density functional theory local-spin-optimized atom-centered basis sets complemented with bond functions optimized at
the mPW1PW level of theory. Calculations show that the mPW1PW functional using bond functions gives a realistic representation
of the interaction-energy potentials for this van der Waals dimer, comparable to reference M?ller–Plesset perturbation theory
calculations. In contrast, the PWPW functional is unable to describe the bonding properties of this system and all values
of the bonding properties obtained at different geometries with this functional are considered out-of-scale compared with
the rest of the calculations presented in this study.
Received: 30 October 2000 / Accepted: 3 January 2001 / Published online: 3 April 2001 相似文献
73.
Oscar Cervantes Zaira del Rocio Lopez Norberto Casillas Peter Knauth Nayeli Checa Francisco Apolinar Cholico Rodolfo Hernandez-Gutirrez Luis Hector Quintero Jose Avila Paz Mario Eduardo Cano 《Molecules (Basel, Switzerland)》2022,27(2)
A ferrofluid with 1,2-Benzenediol-coated iron oxide nanoparticles was synthesized and physicochemically analyzed. This colloidal system was prepared following the typical co-precipitation method, and superparamagnetic nanoparticles of 13.5 nm average diameter, 34 emu/g of magnetic saturation, and 285 K of blocking temperature were obtained. Additionally, the zeta potential showed a suitable colloidal stability for cancer therapy assays and the magneto-calorimetric trails determined a high power absorption density. In addition, the oxidative capability of the ferrofluid was corroborated by performing the Fenton reaction with methylene blue (MB) dissolved in water, where the ferrofluid was suitable for producing reactive oxygen species (ROS), and surprisingly a strong degradation of MB was also observed when it was combined with H2O2. The intracellular ROS production was qualitatively corroborated using the HT-29 human cell line, by detecting the fluorescent rise induced in 2,7-dichlorofluorescein diacetate. In other experiments, cell metabolic activity was measured, and no toxicity was observed, even with concentrations of up to 4 mg/mL of magnetic nanoparticles (MNPs). When the cells were treated with magnetic hyperthermia, 80% of cells were dead at 43 °C using 3 mg/mL of MNPs and applying a magnetic field of 530 kHz with 20 kA/m amplitude. 相似文献
74.
Rocío Quiroga Esther Nistal Brisamar Estbanez David Porras María Jurez-Fernndez Susana Martínez-Flrez María Victoria García-Mediavilla Jos A. de Paz Javier Gonzlez-Gallego Sonia Snchez-Campos María J. Cuevas 《Experimental & molecular medicine》2020,52(7):1048
Childhood obesity has reached epidemic levels and is a serious health concern associated with metabolic syndrome, nonalcoholic fatty liver disease, and gut microbiota alterations. Physical exercise is known to counteract obesity progression and modulate the gut microbiota composition. This study aims to determine the effect of a 12-week strength and endurance combined training program on gut microbiota and inflammation in obese pediatric patients. Thirty-nine obese children were assigned randomly to the control or training group. Anthropometric and biochemical parameters, muscular strength, and inflammatory signaling pathways in mononuclear cells were evaluated. Bacterial composition and functionality were determined by massive sequencing and metabolomic analysis. Exercise reduced plasma glucose levels and increased dynamic strength in the upper and lower extremities compared with the obese control group. Metagenomic analysis revealed a bacterial composition associated with obesity, showing changes at the phylum, class, and genus levels. Exercise counteracted this profile, significantly reducing the Proteobacteria phylum and Gammaproteobacteria class. Moreover, physical activity tended to increase some genera, such as Blautia, Dialister, and Roseburia, leading to a microbiota profile similar to that of healthy children. Metabolomic analysis revealed changes in short-chain fatty acids, branched-chain amino acids, and several sugars in response to exercise, in correlation with a specific microbiota profile. Finally, the training protocol significantly inhibited the activation of the obesity-associated NLRP3 signaling pathway. Our data suggest the existence of an obesity-related deleterious microbiota profile that is positively modified by physical activity intervention. Exercise training could be considered an efficient nonpharmacological therapy, reducing inflammatory signaling pathways induced by obesity in children via microbiota modulation.Subject terms: High-throughput screening, DNA metabolism 相似文献
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José G. Aguirre-De Paz Davir González-Calderón Aydeé Fuentes-Benítes Carlos González-Romero 《Tetrahedron letters》2018,59(18):1760-1762
The exploration of azide-enolate cycloaddition in the synthesis of novel Rufinamide analogs is reported for the first time. A very simple procedure involving the use of β-ketonitriles as dipolarophiles afforded 5-aril/heteroayl Rufinamide derivatives in two steps. 相似文献
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