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Topic Review
Red-Beetroot-Extract in the Biodegradable Polymers
This study investigated the effect of natural antioxidants inherent to beetroot (Beta vulgaris var. Vulgaris) on the ageing of environmentally friendly plastics. Certain properties were examined in this context, comprising thermal, mechanical, and morphological properties. A visual evaluation of relevant changes in the given polymers (polylactide and polycaprolactone) was conducted during an ageing test in a UV chamber (45 °C, 70% humidity) for 720 h. The films were prepared by a casting process, in which samples with the extract of beetroot were additionally incorporated in a common filler (bentonite), this serving as a carrier for the extract. The results showed the effect of the incorporated antioxidant, which was added to stabilize the biodegradable films. Its efficiency during the ageing test in the polymers tended to exceed or be comparable to that of the reference sample. 
  • 1.0K
  • 04 Sep 2021
Topic Review
Gas Chromatography - Vacuum Ultraviolet Spectroscopy (GC-VUV)
Gas Chromatography - Vacuum Ultraviolet (GC-VUV) spectroscopy is a universal detection platform for gas chromatography. The first benchtop detector was introduced in 2014 with detection capabilities between 120 - 240 nm. This portion of the ultraviolet spectrum had historically been restricted to bright source synchrotron facilities due to significant background absorption challenges inherent to working within the wavelength range. Further detector platform development has extended the wavelength detection range out from 120 - 430 nm. VUV detection provides both qualitative and quantitative spectral information for most gas phase compounds. GC-VUV spectral data is three dimensional (time, absorbance, wavelength) and specific to chemical structure. Nearly all compounds absorb in the VUV region of the electromagnetic spectrum with the exception of carrier gases hydrogen, helium, and argon. The high energy, short wavelength VUV photons probe electronic transitions in almost all chemical bonds including ground state to excited state. The result is spectral "fingerprints" that are specific to individual compound structure and can be readily identified by the VUV library. Unique VUV spectra enable closely related compounds such as structural isomers to be clearly differentiated. VUV detectors complement mass spectrometry, which struggles with characterizing constitutional isomers and compounds with low mass quantitation ions. VUV spectra can also be used to deconvolve analyte co-elution, resulting in an accurate quantitative representation of individual analyte contribution to the original response. This characteristically lends itself to significantly reducing GC runtimes through flow rate-enhanced chromatographic compression. VUV spectroscopy follows the simple linear relationship between absorbance and concentration described by the Beer-Lambert Law resulting in more accurate retention time-based identification. VUV absorbance spectra also exhibit feature similarity within compound classes, meaning VUV detectors can rapidly compound class characterization in complex samples through compound spectral shape and retention index information. Advances in technology reduces the typical group analysis data processing time from 15-30 minutes to <1 minute per sample.
  • 1.0K
  • 17 Nov 2022
Topic Review
Cellulose-Based Hydrogels
Hydrogels, three-dimensional (3D) polymer networks, present unique properties, like biocompatibility, biodegradability, tunable mechanical properties, sensitivity to various stimuli, the capacity to encapsulate different therapeutic agents, and the ability of controlled release of the drugs.
  • 1.0K
  • 28 Jan 2021
Topic Review
Mechanism of Cotton Combustion
As a cellulose-based polymer, the combustion of cotton is an exothermic oxidation process that takes place upon heating, consuming flammable gases, liquids, and solid residues produced during the pyrolysis of the textile material, thus generating heat.
  • 1.0K
  • 27 Jul 2023
Topic Review
Micro-Computed Tomography
Micro-computed tomography (micro-CT) is a consolidated imaging technology allowing non-destructive three-dimensional (3D) qualitative and quantitative analysis by the observation of microstructures with high resolution. This paper Ten Years of Micro-CT in Dentistry and Maxillofacial Surgery: A Literature Overview aims at delivering a structured overview of literature about studies performed using micro-CT in dentistry and maxillofacial surgery (MFS) by analyzing the entire set of articles to portray the state of the art of the last ten years of scientific publications on the topic. 
  • 1.0K
  • 23 Feb 2021
Topic Review
Triarylmethyl Radical-Based High-Efficiency OLED
Perchlorotrityl radical (PTM), tris (2,4,6-trichlorophenyl) methyl radical (TTM), (3,5-dichloro-4-pyridyl) bis (2,4,6 trichlorophenyl) methyl radical (PyBTM), (N-carbazolyl) bis (2,4,6-trichlorophenyl) methyl radical (CzBTM), and their derivatives are stable organic radicals that exhibit light emissions at room temperature. Since these triarylmethyl radicals have an unpaired electron, their electron spins at the lowest excited state and ground state are both doublets, and the transition from the lowest excited state to the ground state does not pose the problem of a spin-forbidden reaction. When used as OLED layers, these triarylmethyl radicals exhibit unique light-emitting properties, which can increase the theoretical upper limit of the OLED’s internal quantum efficiency (IQE) to 100%.
  • 1.0K
  • 15 Apr 2022
Topic Review
Shape Changing Materials
This short review is the applications section of our original paper that reviews materials and structures displaying non-conventional deformations as a response to different actuations (e.g., electricity, heat and mechanical loading).
  • 1.0K
  • 27 Oct 2020
Topic Review
The Design of Ni-Based Single Crystal Superalloys
The most important performance characteristics of heat-resistant alloys (HRAs) are creep and fatigue resistance, which are very complex functions of chemical composition and microstructure. The microstructure of metal HRAs, among which the first place is occupied by Ni-based alloys, usually consists of two main phases: a solid solution based on the main element containing alloying elements (matrix), and a strengthening phase, which is usually used as intermetallides, carbides and silicides.
  • 1.0K
  • 17 Jan 2022
Topic Review
G-Quadruplexes: Emerging Anticancer Roles
G-quadruplexes, a family of (thermodynamically and kinetically stable) tetraplex helices, are non-canonical secondary structures derived from guanine (G)-rich sequences of nucleic acids. G-quadruplexes were found to occur in functionally-important regions of the human genome, including the telomere tandem sequences, several proto-oncogene promoters and other regulatory regions, ribosomal DNA (rDNA), as well as mRNA sequences encoding for proteins with roles in tumorigenesis, thus establishing a clear connection between G-quadruplexes and known hallmarks of cancer. Stabilization of G-quadruplexes belonging to the above categories, by means of small-molecule intervention, has been correlated with a range of anticancer effects, which has led to classifying G-quadruplexes as novel potential targets in anticancer research. The most common ways in which G-quadruplexes are now understood to serve in an anticancer capacity are presented herein.
  • 1.0K
  • 03 Mar 2021
Topic Review
Plant-Based Indole Alkaloids
Indole (C8H7N) is a weakly basic molecule consisting of a pyrrole ring fused to a benzene nucleus, and ten π electrons move throughout the structure. The basic environment of indole alkaloids is thought to be caused by the delocalization of the lone pair of nitrogen electrons into the free circulation of the π electronic system. This results in indole becoming protonated at the C-3 position, which is thermodynamically more stable.Indole alkaloids have gained popularity due to their diverse pharmacological activities. Indole alkaloids have been identified in several prominent plant families, including Apocynaceae, Rubiaceae, Nyssaceae, and Loganiaceae, among others. Some of the identified indole alkaloid compounds have been highly effective in pre-clinical and clinical studies. Thousands of compounds containing the indole nucleus have been isolated from plant sources. Their pharmacological activities were assessed, with some now being examined in clinical trials and some already approved for therapeutic use in humans. Indole alkaloids are often characterized by their potent biological activities, which are relevant to the field of medicine, including anticancer, antibacterial, antiviral, antimalarial, antifungal, anti-inflammatory, antidepressant, analgesic, hypotensive, anticholinesterase, antiplatelet, antidiarrheal, spasmolytic, antileishmanial, lipid-lowering, antimycobacterial, and antidiabetic activities. 
  • 1.0K
  • 27 Apr 2021
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