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排序方式: 共有97条查询结果,搜索用时 15 毫秒
11.
Dimitra Vernardou Charalampos Drosos Andreas Kafizas Martyn E. Pemble Emmanouel Koudoumas 《Molecules (Basel, Switzerland)》2020,25(23)
The need for clean and efficient energy storage has become the center of attention due to the eminent global energy crisis and growing ecological concerns. A key component in this effort is the ultra-high performance battery, which will play a major role in the energy industry. To meet the demands in portable electronic devices, electric vehicles, and large-scale energy storage systems, it is necessary to prepare advanced batteries with high safety, fast charge ratios, and discharge capabilities at a low cost. Cathode materials play a significant role in determining the performance of batteries. Among the possible electrode materials is vanadium pentoxide, which will be discussed in this review, due to its low cost and high theoretical capacity. Additionally, aqueous electrolytes, which are environmentally safe, provide an alternative approach compared to organic media for safe, cost-effective, and scalable energy storage. In this review, we will reveal the industrial potential of competitive methods to grow cathodes with excellent stability and enhanced electrochemical performance in aqueous media and lay the foundation for the large-scale production of electrode materials. 相似文献
12.
T. Kouris C. Papadopoulou G. D. Kanias E. Bairaktari-Kouri G. Theodossiadis 《Journal of Radioanalytical and Nuclear Chemistry》1989,130(1):121-128
Cataract is a very common disease of the eye lens known since ancient times. Different mechanisms are responsible for the biogenesis of cataract but most scientists agree with the theory that cataract formation can be attributed to metabolism disorders in the lens. Instrumental neutron activation analysis has been applied in this work for the determination of the following trace elements: antimony, cobalt, iron, rubidium, selenium and zinc in human lenses with mature cataract. The results are statistically treated and correlated with age and sex of patients. Based on these findings, the concentration of elements studied does not have any correlation with the age and/or sex of the patients, i.e. when the lens becomes totally opaque. 相似文献
13.
It is shown that the j plane singularity (Pomeron) which leads to a rising total cross-section like (lns)?, ? > 0. cannot be factorizable in the Mueller diagrams for inclusive production of particles with large rapidity differences. The relevance of this result for the theories of a renormalized Pomeron is discussed. 相似文献
14.
15.
Marina A. Medvedeva Theodore E. Simos Charalampos Tsitouras 《Mathematical Methods in the Applied Sciences》2020,43(4):1582-1589
Implicit Runge-Kutta (RK) methods are in common use when addressing stiff initial value problems (IVP). They usually share the property of A-stability that is of crucial importance in solving the latter type of IVP. Radau IIA family of implicit RK methods is among the preferred ones. Especially its fifth-order representative named RADAU5 has received a lot of attention for use with lax accuracies. Here, we try the lesser possible perturbation of its coefficients. Then, we derive a trigonometric fitted modification that is intended to be applied in periodic IVPs. Numerical tests over a variety of problems with oscillatory solutions justify our effort. 相似文献
16.
It is shown that every properly embedded incompressible surface in a handlebody can be constructed by a canonical gluing process. A simple condition is given which asserts that the result of the gluing process is an incompressible surface. A new notion of isotopy is introduced in order to distinguish surfaces belonging to distinct isotopy classes. Several examples (known and new) are constructed. 相似文献
17.
Papadopoulos Charalampos Mimidis Konstantinos Tentes Ioannis Tente Thaleia Anagnostopoulos Konstantinos 《平面色谱法杂志一现代薄层色谱法》2021,34(5):411-418
JPC – Journal of Planar Chromatography – Modern TLC - A set of constituents of the erythrocyte membrane lipidome has been proposed to serve as biomarkers for liver disease and acute... 相似文献
18.
Maria C. Giannakourou Stylianos Poulis Spyridon J. Konteles Akrivi Dipla Vladimiros P. Lougovois Vassiliki Kyrana Charalampos Proestos Vassilia J. Sinanoglou 《Molecules (Basel, Switzerland)》2021,26(9)
The scope of this work is the study of a combined process including a dipping step into an oregano (Origanum vulgare ssp. hirtum) infusion (OV) followed by osmotic treatment of chicken fillets at 15 °C. Chicken fillets were immersed in an osmotic solution consisting of 40% glycerol and 5% NaCl with (OV/OD) and without (OD) prior antioxidant enrichment in a hypotonic oregano solution. A comparative shelf life study of all the samples (untreated, OD and OV/OD treated) was then conducted at 4 °C in order to assess the impact of this process on the quality and shelf life of chilled chicken fillets. Microbial growth, lipid oxidation and color/texture changes were measured throughout the chilled storage period. Rates of microbial growth of pretreated fillets were significantly reduced, mainly as a result of water activity decrease (OD step). Rancidity development closely related to off odors and sensory rejection was greatly inhibited in treated fillets owing to both inhibitory factors (OD and OV), with water-soluble phenols (OV step) exhibiting the main antioxidant effect. Shelf life of treated chicken fillets exhibited a more than three-fold increase as compared to the untreated samples based on both chemical and microbial spoilage indices, maintaining a positive and pleasant sensory profile throughout the storage period examined. 相似文献
19.
Theodoros Chatzimitakos Charalampos BinellasKaterina Maidatsi Constantine Stalikas 《Analytica chimica acta》2016
The use of magnetic ionic liquids (MILs) is in constant growth due to their switchable properties in the presence of an external magnetic field along with the outstanding properties of ionic liquids. In this study, a novel stirring-assisted drop-breakup microextraction (SADBME) approach is put forward, based on the synthesis and utilization of methyltrioctylammonium tetrachloroferrate (N8 8,8,1[FeCl4]), as a MIL. The proposed procedure complies with the principles of the green chemistry, since it uses low volumes of easily synthesized ILs-based magnetic extracting phases avoiding the use of toxic solvents. To demonstrate its applicability, the proposed microextraction procedure is studied in conjunction with HPLC for the determination of selected phenols and acidic pharmaceuticals in aqueous matrices, taking into account the main experimental variables involved. The results obtained are accurate and highly reproducible, thus making it a good alternative approach for routine analysis of phenols and acidic pharmaceuticals. The low-cost approach is straightforward, environmentally safe and exhibits high enrichment factors and absolute extraction percentages and satisfactory recoveries. To the best of our knowledge, this is the first time that a MIL is used for analytical purposes in a practical, efficient and environmentally friendly drop-breakup microextraction approach for small molecules. 相似文献
20.
Improving the CBS‐based partitioned semi‐implicit coupling algorithm for fluid‐structure interaction 下载免费PDF全文
We detail in this work 2 simple but effective alternatives to improve the characteristic‐based split–based partitioned semi‐implicit coupling algorithm for fluid‐structure interaction. The basic idea lies in introducing the end‐of‐step velocity into the implicit stages of the 2 algorithms integrating different splits. The algorithm built upon the second‐order pressure split is further stabilized via the pressure gradient projection with particular emphasis on the extremely low mass ratio. The smoothed finite element method is exploited for spatial discretization of fluid and solid equations. Even without any accelerators, both the semi‐implicit solvers incorporating fixed‐point iterations engender visible improvements versus the previously published data for several benchmarks. 相似文献