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62.
Novel 2D van der Waals heterostructures with innovative bimetallic oxychloride (Bi‐ and Sb‐based oxychloride) nanosheets that are well dispersed on reduced graphene oxide nanosheets, are established through element engineering for superior potassium ion battery (PIBs) anodes. This material displays an exceptional electrochemical performance, obtaining a discharge capacity as high as 360 mAh g?1 at 100 mA g?1 after running 1000 cycles for over 9 months with a capacity preservation percentage of 88.5% and achieving a discharge capacity as high as 319 mAh g?1 at 1000 mA g?1, in addition to the low charge/discharge plateaus for anodes and promising full cell performance. More significantly, the nature of such 2D van der Waals heterostructures, including the element engineering for morphology control, the function of each component of heterostructures, the mechanism of potassium ion storage, and the process of K+ intercalation accompanied with the lattice distortion and chemical bond breakages, is explored in depth. This study is critical for not only paving the way for the practical application of PIBs but also shedding light on fundamentals of potassium ion storage in 2D van der Waals heterostructures. 相似文献
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Aline Souza Medrado Mavione Souza Ribeiro Paulo Roberto Antunes de Mello Affonso Paulo Luíz Souza Carneiro Marco Ant?nio Costa 《Genetics and molecular biology》2012,35(4):797-801
The fish genus Astyanax is widespread throughout the Neotropical region and is one of the most species-rich genera of the Characiformes. Cytogenetic studies of Astyanax have revealed marked intra- and interspecific diversity, with the identification of various species complexes. In this report, we describe the karyotypic structure of two sympatric species of Astyanax (Astyanax sp. and Astyanax aff. fasciatus) from the Middle Contas River basin in the northeastern Brazilian state of Bahia. Both species had 2n = 48 but differed in their karyotypic formulae. Small heterochromatic blocks and multiple nucleolar organizer regions (NORs) were identified in both species. Terminal CMA3+/DAPI− signals were observed in Astyanax sp. and A. aff. fasciatus, mostly coincident with NORs. These results show that chromosomal markers can be used to identify species in this fish complex. These markers can provide useful information for evolutionary studies and investigations on the mechanisms of chromosomal diversity in Astyanax. 相似文献
66.
André Soares Luís Vasco Louro Marta Almeida Olga Sousa 《Reports of Practical Oncology and Radiotherapy》2012,17(6):384-388
Thymomas are rare neoplasms that have an indolent growth with a preferentially intra-thoracic dissemination pattern. Surgery is currently the standard treatment of thymomas; however radiotherapy is often used in an adjuvant setting due to a high sensitivity of these tumors to such treatment. Postoperative entire hemithoracic irradiation has been used in selected Masaoka stage IVa cases after complete surgical excision of metastatic lesions.In the present article, the authors report three cases of Masaoka stage IVa thymoma that underwent entire hemithorax irradiation after surgical excision of metastatic lesions. The first two patients presented as stage IVa thymomas. The third case consisted of a pleural recurrence of a thymoma.Hemithoracic irradiation with low doses has been used by different authors; the available data shows that it is a well-tolerated treatment that could potentially lead to better loco-regional control and increased overall survival. 相似文献
67.
Cristina Castillo José Luís Benedito Patricia Vázquez Víctor Pereira Jesús Méndez Juan Sotillo Joaquín Hernández 《Animal Feed Science and Technology》2012,171(2-4):246-250
This study investigated the in vivo effects of a commercial blend of plant extracts (carvacrol, cinnamaldehyde and capsaicin) on serum metabolic parameters closely connected with energy and protein metabolism (glucose; l-lactate; non-esterified fatty acids, NEFA; urea nitrogen, SUN; creatinine; total protein, TSP) and enzymes associated with hepatic function (aspartate-aminotransferase, AST and gamma-glutamyl transferase, GGT) in finishing-stage Belgian Blue bull calves maintained in a commercial feedlot. Monitoring was performed over 86 days in 24 animals randomly allotted to two groups: (1) a control group (CTR, no supplementation; n = 10), and (2) a group receiving dietary supplementation with a commercial blend of plant extracts (PEX, 100 mg/kg DM of concentrate; n = 14). Under the conditions of our study, supplementation with the commercial blend did not give detrimental effects, but the opposite: the decrease in serum l-lactate, NEFA and creatinine levels and the increase in SUN concentrations; suggests an improvement in the energy status and protein turnover of the supplemented animals. 相似文献
68.
Shoot-tips of Rabdosia rubescens, excised from in vitro-grown proliferating shoots that were cold-hardened at 5°C for 3 weeks, were encapsulated in alginate
beads. Subsequently, these were precultured in a mixture of 0.4 M sucrose and 2 M glycerol for 1 h and then desiccated with
silica-gel to about 21% water content prior to freezing in liquid nitrogen. After thawing, about 85% of cryopreserved shoot-tips
grew into true-to-type shoots and with enhanced rooting capacity. Eight single-bud sibling lines were used to assess genetic
stability of these encapsulated shoot-tips. When the relative DNA content was measured by flow cytometry (FCM), no changes
were observed between controls and cryopreserved shoots. Using a sequence-related amplified polymorphism (SRAP) assay, it
was observed that seven out of eight cryopreserved lines showed identical banding patterns; while the eighth line displayed
an absent band, amounting to a low variance rate of 0.01%. These findings suggested that it was necessary to monitor the genetic
stability of recovered cryopreserved R. rubescens shoots. 相似文献
69.
Seetharamaiyer Padmanabhan Ruth C. Lavin Paresh M. Thakker Jinqing Guo Lu Zhang Deke Moore Michael E. Perlman Cassandra Kirk Deborah Daly Kathy J. Burke-Howie Teresa Wolcott Suchitra Chari David Berlove James B. Fischer William F. Holt Graham J. Durant Robert N. McBurney 《Bioorganic & medicinal chemistry letters》2001,11(24):1945-3155
Solution-phase synthesis of various acylguanidine derivatives and the evaluation of a small library of compounds as potential sodium channel blockers are described. 相似文献
70.