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排序方式: 共有407条查询结果,搜索用时 265 毫秒
401.
Marco Agostini Laura Giorgia Rizzi Giulio Cesareo Valeria Russo Jusef Hassoun 《Advanced Materials Interfaces》2015,2(8)
A Cu‐supported, graphene nanoplatelet (GNP) electrodes are reported a as high performance anode in lithium ion battery. The electrode precursor is an easy‐to‐handle aqueous ink cast on cupper foil and following dried in air. The scanning electron microscopy evidences homogeneous, micrometric flakes‐like morphology. Electrochemical tests in conventional electrolyte reveal a capacity of about 450 mAh g−1 over 300 cycles, delivered at a current rate as high as 740 mA g−1. The graphene‐based electrode is characterized using a N‐butyl‐N‐methyl‐pyrrolidiniumbis (trifluoromethanesulfonyl) imide, lithium‐bis(trifluoromethanesulfonyl)imide (Py1,4TFSI–LiTFSI) ionic liquid‐based solution added by ethylene carbonate (EC): dimethyl carbonate (DMC). The Li‐electrolyte interface is investigated by galvanostatic and potentiostatic techniques as well as by electrochemical impedance spectroscopy, in order to allow the use of the graphene‐nanoplatelets as anode in advanced lithium‐ion battery. Indeed, the electrode is coupled with a LiFePO4 cathode in a battery having a relevant safety content, due to the ionic liquid‐based electrolyte that is characterized by an ionic conductivity of the order of 10−2 S cm−1, a transference number of 0.38 and a high electrochemical stability. The lithium ion battery delivers a capacity of the order of 150 mAh g−1 with an efficiency approaching 100%, thus suggesting the suitability of GNPs anode for application in advanced configuration energy storage systems. 相似文献
402.
403.
Corrales J Naja GM Dziuba C Rivero RG Orem W 《The Science of the total environment》2011,409(11):2156-2162
Sulfate contamination has a significant environmental implication through the stimulation of toxic hydrogen sulfide and methylmercury (MeHg) production. High levels of MeHg are a serious problem in many wetland ecosystems worldwide. In the Florida Everglades, it has been demonstrated that increasing MeHg occurrence is due to a sulfate contamination problem. A promising strategy of lowering the MeHg occurrence is to reduce the amount of sulfate entering the ecosystem. High surface water sulfate concentrations in the Everglades are mainly due to discharges from the Everglades Agricultural Area (EAA) canals. Water and total sulfur mass balances indicated that total sulfur released by soil oxidation, Lake Okeechobee and agricultural application were the major sources contributing 49,169, 35,217 and 11,775 mtons year− 1, respectively. Total sulfur loads from groundwater, levees, and atmospheric deposition contributed to a lesser extent: 4055; 5858 and 4229 mtons year− 1, respectively. Total sulfur leaving the EAA into Water Conservation Areas (WCAs) through canal discharge was estimated at 116,360 mtons year−1, and total sulfur removed by sugarcane harvest accounted for 23,182 mtons year− 1. Furthermore, a rise in the mineral content and pH of the EAA soil over time, suggested that the current rates of sulfur application would increase as the buffer capacity of the soil increases. Therefore, a site specific numeric criterion for sulfate of 1 mg L− 1 was recommended for the protection of the Everglades; above this level, mercury methylation is enhanced. In parallel, sulfide concentrations in the EAA exceeded the 2 μg L− 1 criterion for surface water already established by the U.S. Environmental Protection Agency (EPA). 相似文献
404.
Rosalba Siracusa Francesco Monaco Ramona DAmico Tiziana Genovese Marika Cordaro Livia Interdonato Enrico Gugliandolo Alessio Filippo Peritore Rosalia Crupi Salvatore Cuzzocrea Daniela Impellizzeri Roberta Fusco Rosanna Di Paola 《International journal of molecular sciences》2021,22(13)
Treating postoperative (PO) pain is a clinical challenge. Inadequate PO pain management can lead to worse outcomes, for example chronic post-surgical pain. Therefore, acquiring new information on the PO pain mechanism would increase the therapeutic options available. In this paper, we evaluated the role of a natural substance, epigallocatechin-3-gallate (EGCG), on pain and neuroinflammation induced by a surgical procedure in an animal model of PO pain. We performed an incision of the hind paw and EGCG was administered for five days. Mechanical allodynia, thermal hyperalgesia, and motor dysfunction were assessed 24 h, and three and five days after surgery. At the same time points, animals were sacrificed, and sera and lumbar spinal cord tissues were harvested for molecular analysis. EGCG administration significantly alleviated hyperalgesia and allodynia, and reduced motor disfunction. From the molecular point of view, EGCG reduced the activation of the WNT pathway, reducing WNT3a, cysteine-rich domain frizzled (FZ)1 and FZ8 expressions, and both cytosolic and nuclear β-catenin expression, and the noncanonical β-catenin–independent signaling pathways, reducing the activation of the NMDA receptor subtype NR2B (pNR2B), pPKC and cAMP response element-binding protein (pCREB) expressions at all time points. Additionally, EGCG reduced spinal astrocytes and microglia activation, cytokines overexpression and nuclear factor kappa-light-chain-enhancer of activated B cells (NFkB) pathway, downregulating inducible nitric oxide synthase (iNOS) activation, cyclooxygenase 2 (COX-2) expression, and prostaglandin E2 (PGE2) levels. Thus, EGCG administration managing the WNT/β-catenin signaling pathways modulates PO pain related neurochemical and inflammatory alterations. 相似文献
405.
406.
Tiziana Genovese Marika Cordaro Rosalba Siracusa Daniela Impellizzeri Sebastiano Caudullo Emanuela Raffone Francesco Macrí Livia Interdonato Enrico Gugliandolo Claudia Interlandi Rosalia Crupi Ramona DAmico Roberta Fusco Salvatore Cuzzocrea Rosanna Di Paola 《International journal of molecular sciences》2022,23(10)
Endometriosis is usually associated with inflammation and chronic pelvic pain. This paper focuses the attention on the anti-inflammatory, anti-oxidant and analgesic effects of cannabidiol (CBD) and on its potential role in endometriosis. We employed an in vivo model of endometriosis and administered CBD daily by gavage. CBD administration strongly reduced lesions diameter, volume and area. In particular, it was able to modify lesion morphology, reducing epithelial glands and stroma. CBD showed anti-oxidant effects reducing lipid peroxidation, the expression of Nox-1 and Nox-4 enzymes. CBD restored the oxidative equilibrium of the endogenous cellular defense as showed by the SOD activity and the GSH levels in the lesions. CBD also showed important antifibrotic effects as showed by the Masson trichrome staining and by downregulated expression of MMP-9, iNOS and TGF-β. CBD was able to reduce inflammation both in the harvested lesions, as showed by the increased Ikb-α and reduced COX2 cytosolic expressions and reduced NFkB nuclear localization, and in the peritoneal fluids as showed by the decreased TNF-α, PGE2 and IL-1α levels. CBD has important analgesic effects as showed by the reduced mast cells recruitment in the spinal cord and the reduced release of neuro-sensitizing and pro-inflammatory mediators. In conclusion, the collected data showed that CBD has an effective and coordinated effects in endometriosis suppression. 相似文献
407.
Colour science has had a very long history, dotted over the millennia with many contributions from the most diverse fields of human knowledge. At the beginning of the 20th century, Albert Henry Munsell, an artist formally trained in academia, and Friedrich Wilhelm Ostwald, Nobel prize for chemistry in 1909 and amateur painter, each envisioned and developed a colour system with a related colour atlas. Both authors recognized the importance of the visual relationship between colours, which they conceived as sensations stemming from, but not merely confined to, pigments and light. We hereby describe the salient features of these colour spaces, their strengths and weaknesses, the authors' analogy of intents and divergence in execution. The contribution of this paper is a discussion on how these are employed both in Italian educational facilities, and salon practice, as well as a suggestion about their use within the industry of human hair cosmetics. 相似文献