9 resultados para lithium battery

em University of Queensland eSpace - Australia


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Ordered mesoporous carbon CMK-5 was comprehensively tested for the first time as electrode materials in lithium ion battery. The surface morphology, pore structure and crystal structure were investigated by Scanning Electronic Microscopy (SEM), N-2 adsorption technique and X-ray diffraction (XRD) respectively. Electrochemical properties of CMK-5 were studied by galvanostatic cycling and cyclic voltammetry, and compared with conventional anode material graphite. Results showed that the reversible capacity of CMK-5 was 525 mAh/g at the third charge-discharge cycle and that CMK-5 was more compatible for quick charge-discharge cycling because of its special mesoporous structure. Of special interest was that the CMK-5 gave no peak on its positive sweep of the cyclic voltammetry, which was different from all the other known anode materials. Besides, X-ray photoelectron spectroscopy (XPS) and XRD were also applied to investigate the charge-discharge characteristics of CMK-5.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Ordered nanoporous carbon (ONC) was comprehensively tested for the first time as electrode material in lithium-ion battery. Structure characterization shows the order nanoporous structure and tiny crystallite structure of as-synthesized ONC. The electrochemical properties of this carbon were studied by galvanostatic cycling and cyclic voltammetry. Of special interest is that ONC gave no peak on its positive sweep of the cyclic voltammetry, which was different from other known anode materials. Besides, X-ray photoelectron spectroscopy (XPS) and XRD were also used to investigate the electrochemical characteristics of ONC. (c) 2006 Elsevier Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The phenotypic and genetic factor structure of performance on five Multidimensional Aptitude Battery (MAB) subtests and one Wechsler Adult Intelligence Scale-Revised (WAIS-R) subtest was explored in 390 adolescent twin pairs (184 monozygotic [MZ]; 206 dizygotic (DZ)). The temporal stability of these measures was derived from a subsample of 49 twin pairs, with test-retest correlations ranging from .67 to .85. A phenotypic factor model, in which performance and verbal factors were correlated, provided a good fit to the data. Genetic modeling was based on the phenotypic factor structure, but also took into account the additive genetic (A), common environmental (C), and unique environmental (E) parameters derived from a fully saturated ACE model. The best fitting model was characterized by a genetic correlated two-factor structure with specific effects, a general common environmental factor, and overlapping unique environmental effects. Results are compared to multivariate genetic models reported in children and adults, with the most notable difference being the growing importance of common genes influencing diverse abilities in adolescence. (C) 2003 Elsevier Inc. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Clinicians frequently use lithium to augment antipsychotic medication in schizophrenia. Therefore, we undertook a systematic review and meta-analysis of the use of lithium in the treatment of schizophrenia. Data sources and study selection: Randomized controlled trials examining lithium (as a sole or an adjunctive compound) in participants with schizophrenia or related disorders were searched in the register of the Cochrane Schizophrenia Group. No language restrictions were applied. The Boolean phrase [lithium* or lithicarb or eskalith or lithobid or lithane or cibalith-s or quilonum or hypnorex] was used to locate articles. The search strategy initially identified 90 references. The authors of the included studies were contacted to obtain original patient data. The data were combined in a meta-analysis. The main outcome parameters were the number of patients with a clinically significant response and the number of patients leaving the studies early. Results: The meta-analysis includes 20 studies (N = 611). The evidence shows that lithium as a sole agent is ineffective in the treatment of schizophrenia. Eleven trials examined the augmentation of antipsychotics with lithium. More patients who received lithium augmentation than those who received antipsychotics alone were classified as responders. However, the superiority was not consistent across different response thresholds, and when patients with prominent affective symptoms were excluded from the analysis, the advantage of lithium augmentation was not significant (p = .07). Significantly more patients taking lithium left the trials early, suggesting a lower acceptability of lithium augmentation compared with that of taking antipsychotics alone. Conclusion: Despite some evidence in favor of lithium augmentation, the overall results are inconclusive. A large trial of lithium augmentation of antipsychotic medications will be required in order to detect a benefit of small effect size in patients with schizophrenia who lack affective symptoms.