The modification of nitrogen-contaminated diamonds into color-enhanced diamonds is usually achieved by irradiation and thermal treatment (annealing). These treatments affect nitrogen contamination chemical bonding, vacancy concentration, and atom orientation centers in the diamond lattice. In this study, natural diamonds were subjected to irradiation and thermal annealing color enhancement treatments to produce green, blue, and yellow fancy diamonds. The study followed the changes that occur during treatment relying on visual assessment, fluorescence, UV-vis, FTIR, and EPR spectroscopy to characterize paramagnetic centers. The results indicated that diamonds containing high levels of nitrogen contamination presented a relatively high carbon-centered radical concentration. Two paramagnetic groups with different -values were found, namely, low -value centers of 2.0017-2.0027 and high -value centers of 2.0028-2.0035. It is suggested that the 2.0017-2.0022 centers correlate with blue centers, whereas the 2.0023-2.0027 centers correlate with yellow centers. It was also found that thermal treatment was required to produce blue and yellow fancy diamonds, whereas no such treatment was needed to produce green diamonds.
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http://dx.doi.org/10.1039/d2cp00764a | DOI Listing |
PLoS One
December 2024
CIBIO, Research Centre in Biodiversity and Genetic Resources, InBIO, Universidade do Porto, Vila do Conde, Portugal.
Thermoregulating ectotherms may resort to different external heat sources to modulate their body temperature through an array of behavioural and physiological adaptations which modulate heat exchange with the environment and its distribution across the animal's body. Even small-bodied animals are capable of fine control over such rates and the subsequent re-allocation of heat across the body. Such thermal exchanges with the environment usually happen through two non-mutually exclusive modes: heliothermy (radiant heat gain from the sun) or thigmothermy (heat gained or lost via conduction).
View Article and Find Full Text PDFAnn Ital Chir
December 2024
Radiotherapy Department, Affiliated Hospital of Hebei University, 071003 Baoding, Hebei, China.
Front Neurosci
December 2024
Basic Medical School, Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China.
Background: Neuropathic pain (NeP) presents considerable challenges in terms of effective management and significantly impacts the quality of life for affected patients. The current treatment options for NeP are limited, highlighting the need for alternative therapeutic approaches. Dahuang Fuzi Decoction (DF), a formula from traditional Chinese medicine, has shown potential in relieving pain symptoms associated with various types of NeP.
View Article and Find Full Text PDFFront Vet Sci
December 2024
Research Group in Bioclimatology, Ethology and Animal Welfare (BioEt), Department of Animal Science, Federal University of Paraiba, Areia, Paraiba, Brazil.
The present study aimed to evaluate the effects of different nutritional plans on meat quails subjected to heat stress. A total of 324 quails male European quails () were used, with an average initial weight of 121.48 g ± 3.
View Article and Find Full Text PDFFood Sci Nutr
December 2024
Department of Food Engineering, Faculty of Agriculture Atatürk University Erzurum Türkiye.
Pomegranate is one of the most popular fruits worldwide, and it is important to maintain the overall quality and bioaccessibility of freshly squeezed pomegranate juices (PJS). The adverse effects of heat treatment on sensory properties and phytochemicals encourage the use of non-thermal processes in the juice industry. Hereby, the effects of high-pressure homogenization (HPH) (50, 100, and 150 MPa) on the physicochemical properties, antimicrobial activity, in vitro bioaccessibility, and antioxidant capacity of freshly-squeezed PJS from different genotypes were investigated.
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