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Topic Review
New Fenton Catalysts
It is needed found Fenton catalysts with higher reaction rates with catalitic activity similar to the conventional catalysts. The spinel ferrites have attracted increasing interest due to their low cost, excellent catalytic activity, and magnetic properties that allow a facile separation and reutilization, in addition the presence of two differents metals in an same structure can result in a better catalitic activity. Undwer the same idea the perovskites also result interesting for its use as Fenton catalysts due to the sinergic effect betwen the metals of its structure.
  • 253
  • 05 May 2023
Topic Review
New Antimicrobial Oleanonic Acid Polyamine Conjugates
The series of 21 oleanolic acid derivatives containing di- and polyamine fragments at position C3 and C28 was synthesized and evaluated for their antimicrobial activities against both Gram-positive and Gram-negative bacterial. Almost all series presented good to moderate Minimum Inhibitory Concentrations (MIC) against Gram-positive S. aureus, S. faecalis and B. cereus bacteria, moreover compounds possess important antimicrobial activities against Gram-negative E. coli, P. aeruginosa, S. enterica, and EA289 bacteria with MICs ranging from 6.25 to 200 µg/mL. The SAR data showed that the nature of the polyamine fragment, as well as differences in the structure of oleanolic acid plays an important role in the potential activities of tested compounds. The testing of the ability to restore the antibiotic activity of doxycycline and erythromycin at a 2 µg/mL concentration in a synergistic assay showed that only Mannich base with spermine fragment 6 lead to a moderate improvement in terms of antimicrobial activities of the different selected combinations against both P. aeruginosa and E. coli. The study of the mechanism of action of the most important compound in this series (amide 2i derived from N-methyl-norspermidine) showed the effect of disruption of the outer bacterial membrane of P. aeruginosa PA01 cells. Computational ADMET profiling renders compound 2i as a suitable starting point for pharmacokinetic optimization.
  • 480
  • 19 Jan 2022
Topic Review
Neutron Powder Diffraction in Metal Halide Solid-State Electrolytes
Metal halide solid-state electrolytes (SSEs) (Li-M-X system, typically Li3MX6 and Li2MX4; M is metal or rare-earth element, X is halogen) exhibit significant potential in all solid-state batteries (ASSB) due to wide stability windows (0.36–6.71 V vs. Li/Li+), excellent compatibility with cathodes, and a water-mediated facile synthesis route for large-scale fabrication. Understanding the dynamics of Li+ transportation and the influence of the host lattice is the prerequisite for developing advanced Metal halide SSEs. Neutron powder diffraction (NPD), as the most cutting-edge technology, could essentially reflect the nuclear density map to determine the whole crystal structure. Through NPD, the Li+ distribution and occupation are clearly revealed for transport pathway analysis, and the influence of the host ion lattice on Li+ migration could be discussed.
  • 201
  • 20 Oct 2023
Topic Review
Neutralization
In chemistry, neutralization or neutralisation (see spelling differences) is a chemical reaction in which acid and a base react quantitatively with each other. In a reaction in water, neutralization results in there being no excess of hydrogen or hydroxide ions present in the solution. The pH of the neutralized solution depends on the acid strength of the reactants.
  • 1.4K
  • 22 Nov 2022
Topic Review
Neuroprotective Diets
Nutrition and rehabilitation are crucial in post-stroke recovery, especially in the elderly. Since stroke is the leading cause of long-term disability, there is a need to promote special, individually tailored nutrition strategies targeting older patients with low motor ability. Chronic stroke survivors have higher risk of developing nutrition-related chronic diseases, such as sarcopenia, anemia, type 2 diabetes mellitus and osteoporosis.
  • 573
  • 10 Aug 2021
Topic Review
Neuromorphic Computing
Neuromorphic computing systems aims at processing information in a way similar to the human brain. Instead of a conventional von Neumann computer, a neuromorphic system generally relies on a neural network, where the memory and the processing elements are intimately co-located within the same hardware. Neuromorphic computing takes advantage of computational memories, which can both store and process data via physical laws within the device and/or the circuit. This entry summarizes the history and main concepts of neuromorphic computing, including both deep neural networks (DNNs) which are adopted for extensive artificial intelligence tasks, such as driverless cars, and spiking neural networks (SNNs), which aim at a more realistic brain-inspired computation. 
  • 2.5K
  • 22 Jan 2021
Topic Review
Neoproterozoic Fold Belts Surrounding the São Francisco Craton
The São Francisco craton and its continuation in Africa, the Congo Craton, constitute Archean–Paleoproterozoic paleocontinents which, via various continental collisions during the Neoproterozoic–Cambrian, formed the western portion of the Gondwana supercontinent. The folded Brasiliano/Pan African belts occur on the margins of the paleocontinents in the form of several superimposed sedimentary basins, showing different types of magmatic arcs (accretionary material) and which, via collisional processes, were transformed into Neoproterozoic–Cambrian orogenic belts.
  • 143
  • 21 Feb 2024
Topic Review
Near-Infrared-II Fluorophores for Spectra-Domain Multichannel Biosensing
The pathological process involves a range of intrinsic biochemical markers. The detection of multiple biological parameters is imperative for providing precise diagnostic information on diseases. In vivo multichannel fluorescence biosensing facilitates the acquisition of biochemical information at different levels, such as tissue, cellular, and molecular, with rapid feedback, high sensitivity, and high spatiotemporal resolution. The implementation of in vivo multichannel fluorescence biosensing requires a meticulous selection of nonoverlap excitation–emission wavelengths for the use of NIR-II fluorophores. To achieve simultaneous visualization/tracking of multiple analytes at the tissue or cellular level, fluorophores with varying excitation–emission properties are necessary to bind specific targets. 
  • 263
  • 16 Aug 2023
Topic Review
Near-Infrared Spectrum of Olive Oils
Olive oil is regarded as one of the healthiest food oils due to its high content in triglycerides with unsaturated acids, mainly oleic acid, and its phenolic composition. The analysis of the physico-chemical parameters of quality of olive oil is still carried out in laboratories using chemicals and generating waste, which is relatively costly and time-consuming. Among the various alternatives for the online or on-site measurement of these parameters, the available literature highlights the use of near-infrared spectroscopy (NIRS). 
  • 1.4K
  • 18 Apr 2022
Topic Review
Near-Infrared Spectroscopy Coupled to Hyperspectral Imaging
Near-infrared (800–2500 nm; NIR) spectroscopy coupled to hyperspectral imaging (NIR-HSI) has greatly enhanced its capability and thus widened its application and use across various industries. This non-destructive technique that is sensitive to both physical and chemical attributes of virtually any material can be used for both qualitative and quantitative analyses.
  • 1.2K
  • 18 Mar 2022
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