Change In Color Research Articles

Analysis of the effect of three different blanching processes on the flavor profile of peeled and unpeeled broad beans.

Broad beans, a seasonal leguminous vegetable renowned for their distinctive flavor and high-quality plant protein, present unique opportunities for culinary and nutritional applications. To better understand the impact of various blanching processes on their characteristics, we employed headspace gas chromatography-ion mobility mass spectrometry (HS-GC-IMS) and biochemical tests to evaluate changes in color, volatile compound content, and levels of antioxidant-related substances following different blanching treatments. Our findings revealed that microwave blanching significantly influenced the a* metric and antioxidant capacity of broad beans. Specifically, we identified 44 volatile compounds in peeled broad beans and 57 in unpeeled ones. The steam-blanched broad beans retained a flavor profile similar to the control samples, characterized by relatively high concentrations of alcohols, aldehydes, and esters, contributing to a fruity and fresh aroma. In contrast, microwave blanching led to higher concentrations of aldehydes and alcohols and introduced additional odor characteristics such as mushroom, cocoa, and almond notes, enhancing the complexity of the flavor profile. This study provided the essential knowledge for further utilization of broad beans as well as the extension of their shelf life.

Bisphenol A induces sex-dependent alterations in the neuroendocrine response of Djungarian hamsters to photoperiod.

In nature, species synchronize reproduction and energy metabolism with seasons to optimize survival and growth. This study investigates the effect of oral exposure to bisphenol A (BPA) on phenotypic and neuroendocrine seasonal adaptations in the Djungarian hamster, which in contrast to conventional laboratory rodents, is a well-recognized seasonal model. Adult female and male hamsters were orally exposed to BPA (5, 50, or 500 μg/kg/d) or vehicle during a 10-week transition from a long (LP) to short (SP) photoperiod (winter transition) or vice versa (summer transition). Changes in body weight, food intake, and pelage color were monitored weekly and, at the end of the exposure, expression of hypophysio-hypothalamic markers of photoperiodic (TSHβ, deiodinases), reproductive (Rfrp, kisspeptin) and metabolic (somatostatin, Pomc) integration, reproductive organ activity, and glycemia were assessed. Our results revealed sex-specific effects of BPA on acquiring SP and LP phenotypes. During LP to SP transition, females exposed to 500 μg/kg/d BPA exhibited delayed body weight loss and reduced feed efficiency associated with a lower expression of somatostatin, while males exposed to 5 μg/kg/d BPA showed an accelerated acquisition of SP-induced metabolic parameters. During SP to LP transition, females exposed to 5 μg/kg/d BPA displayed a faster LP adaptation in reproductive and metabolic parameters, along with kisspeptin downregulation occurring 5 weeks earlier and Pomc upregulation delayed for up to 10 weeks. In males, BPA exposure led to decreased expression of central photoperiodic integrators, with no effect on the acquisition of the LP phenotype. This pioneering study investigating EDC impacts on mammalian seasonal physiology shows that BPA alters the dynamic of metabolic adaptation to both SP and LP transitions with marked sex dimorphism, causing temporal discordance in seasonal adaptation between males and females. These findings emphasize the importance of investigating EDCs' impact on non-conventional animal models, providing insights into wildlife physiology.

Artificial Intelligence in Diagnosis and Management of Nail Disorders: A Narrative Review.

Artificial intelligence (AI) is revolutionizing healthcare by enabling systems to perform tasks traditionally requiring human intelligence. In healthcare, AI encompasses various subfields, including machine learning, deep learning, natural language processing, and expert systems. In the specific domain of onychology, AI presents a promising avenue for diagnosing nail disorders, analyzing intricate patterns, and improving diagnostic accuracy. This review provides a comprehensive overview of the current applications of AI in onychology, focusing on its role in diagnosing onychomycosis, subungual melanoma, nail psoriasis, nail fold capillaroscopy, and nail involvement in systemic diseases. A literature review on AI in nail disorders was conducted via PubMed and Google Scholar, yielding relevant studies. AI algorithms, particularly deep convolutional neural networks (CNNs), have demonstrated high sensitivity and specificity in interpreting nail images, aiding differential diagnosis as well as enhancing the efficiency of diagnostic processes in a busy clinical setting. In studies evaluating onychomycosis, AI has shown the ability to distinguish between normal nails, fungal infections, and other differentials, including nail psoriasis, with a high accuracy. AI systems have proven effective in identifying subungual melanoma. For nail psoriasis, AI has been used to automate the scoring of disease severity, reducing the time and effort required. AI applications in nail fold capillaroscopy have aided the analysis of diagnosis and prognosis of connective tissue diseases. AI applications have also been extended to recognize nail manifestations of systemic diseases, by analyzing changes in nail morphology and coloration. AI also facilitates the management of nail disorders by offering tools for personalized treatment planning, remote care, treatment monitoring, and patient education. Despite these advancements, challenges such as data scarcity, image heterogeneity, interpretability issues, regulatory compliance, and poor workflow integration hinder the seamless adoption of AI in onychology practice. Ongoing research and collaboration between AI developers and nail experts is crucial to realize the full potential of AI in improving patient outcomes in onychology.

Comparative Analysis of Whitening Outcomes of Over-the-Counter Toothpastes: An In Vitro Study

Background/Objectives: Whiter teeth are widely accepted as the most beautiful. With the growing demand for whiter teeth, several manufacturers have launched different brands of whitening toothpaste claiming to be effective in removing tooth stains and whitening teeth. The objective of this in vitro study was to evaluate and compare the whitening effect of eight over-the-counter available toothpastes by measuring the changes in color using a digital colorimeter in a simulated staining–brushing cycle model. Methods: A total of 32 extracted bovine enamel were polished with 1000–2000 grit SIC paper and immersed in a tea staining solution for 30 min at 37 °C to create extrinsic staining. The specimens were randomly divided into eight groups (n = 4) and subjected to a staining–brushing cycle for 2 weeks. During this period, the specimens were stained for 5 min twice, brushed for 2 min twice per day, and immersed in artificial saliva for the remaining time. The colors of the enamel surfaces L*, a*, and b* were recorded, and the color difference (ΔE) was measured before the treatment and after 1 and 2 weeks of the staining–brushing cycle. Results: The repeated measures showed a significant reduction of (ΔE) after 1 week of the staining–brushing cycle in all eight experimental groups (p < 0.05). The (ΔE) was significantly reduced after the second week of the staining–brushing cycle in groups 1, 3, and 5 (p < 0.05). However, it was insignificant in groups 2, 6, 7, and 8 (p > 0.05). Among the tested materials, group 1 showed the highest and group 8 showed the lowest teeth-whitening effects. Conclusions: The over-the-counter toothpaste used in this study showed effective teeth-whitening. Charcoal-based toothpaste showed the highest efficiency in teeth whitening.

A Schiff-base-modified Cu nanocluster with redox dual-catalytic sites and fluorescence sensing for the degradation and detection of atrazine.

Atrazine is a widely used and heavily contaminating pesticide. In this work, we designed and synthesized a versatile catalyst for the degradation and fluorescent detection of atrazine. This catalyst consists of Cu clusters modified by a Schiff base. The combination of Cu clusters and Schiff base enables it to act as a catalyst with the dual roles of oxidation and reduction. The inclusion of the Schiff base also narrows the band gap of Cu clusters and accelerates the redox electron transfer, leading to the degradation of atrazine up to 98%. Furthermore, the red fluorescence of Cu clusters and the green fluorescence of Schiff base allow this catalyst to sense atrazine like a sensor by a change in fluorescence color. The limit of detection for atrazine is as low as 0.1 nM and visual limit of detection is 10 nM. The mechanisms of catalysis and fluorescence sensing of the catalyst are verified by mass spectrometry and density functional theory. This multi-functional catalyst has great application potential in environmental protection, health and safety and other fields.

The establishment of blue-sky index: how to quantify the aerosol optical impacts on sky color

Abstract Color of the sky serves as a direct indicator of haze, while also exerting substantial influence on human physiological and psychological well-being, as well as the overall environmental scenery. However, quantifying color changes is quite challenging. This research develops a quantitative approach for evaluating the influence of atmospheric aerosol pollution on the appearance of the sky. We first calculated the influence of atmospheric aerosols on the sky’s diffuse radiation, which is the source of sky color. Then, we mapped the diffuse radiation onto a perceptually uniform color space to quantify alterations in sky color. The results reveal that the relationship between aerosol concentration and sky color change follows a logarithmic-like distribution: the higher the concentration, the weaker the change in sky color per unit increase in aerosol concentration. Consequently, during the early phases of air pollution control implementation, there may be minimal observable changes in the color of the sky. However, as these measures are further enforced, a discernible bluing effect on the sky will become evident. Based on the quantification of the change of sky color, a blue-sky index (BSI) was established. We find that concurrent with improvements in air quality resulting from emission reduction measures, the BSI has significantly decreased in recent years in China. This trend indicates an increase in the frequency of blue-sky occurrences.

Single-Atom Iridium-doped Carbon Dots Nanozyme with High Peroxidase-Like Activity as Colorimetric Sensors for Multimodal Detection of Mercury Ions.

Nanozyme-based colorimetric sensors are promising approaches for environmental monitoring, food safety, and medical diagnostics. However, developing novel nanozymes that exhibit high catalytic activity, good dispersion in aqueous solution, high sensitivity, selectivity, and stability is challenging. In this study, for the first time, single-atom iridium-doped carbon dot nanozymes (SA Ir-CDs) are synthesized via a simple in situ pyrolysis process. Doping carbon dots with iridium in the form of single atoms to achieve maximum atomic utilization not only enhances peroxidase (POD)-like activity to 178.81 U mg-1 but also improves the dispersibility of single-atom nanozymes in aqueous solutions over 30 days. Hence, the SA Ir-CD colorimetric platform is developed for mercury ions (Hg2+) detection and exhibited a good linear relationship from 0.01 to 10 µm and a detection limit of 4.4 nm. Notably, the changes in color can be observed not only through the naked eye but also via a smartphone, enabling convenient field and onsite monitoring without the need for sophisticated analytical equipment. In this study, an approach for fabricating single-atom metal-based carbon dot nanozymes with high POD-like activity is developed, and a new effective and easy-to-use colorimetric sensor for Hg2+ detection is constructed.

Establishment of a Breeding Approach Combined with Gamma Ray Irradiation and Tissue Regeneration for Highbush Blueberry

Blueberries are a relatively recently domesticated species, primarily bred through hybridization. Mutation breeding, which uses chemical or physical treatment to increase plant mutation, has not yet been applied to blueberries. This study introduces a mutation breeding strategy for the highbush blueberry cultivar Vaccinium corymbosum. We established a high-efficiency regeneration protocol, which was applied to leaves and stems exposed to gamma irradiation using 60Co-γ rays at doses of 10, 20, 40, 80, and 120 gray (Gy), to increase the efficiency of mutated cells to develop into adventitious shoots. We determined that the median lethal dose (LD50) was approximately 56 Gy for leaf explants and 80 Gy for stem explants. Phenotypic variations, including changes in leaf color and growth characteristics, which may be due to altered plant response to environmental factors, were successfully observed in the first-generation (M1) plants. The height of M1 plants quantitatively decreased with increasing irradiation doses. To evaluate the mutants induced by each irradiation dose, whole-genome resequencing was conducted on individuals from each dose group, revealing significant genomic alterations at the 80 Gy dose. This approach provides a valuable reference for future blueberry breeding programs aimed at enhancing genetic diversity and improving cultivar performance.

Exploring and analyzing the causes of color in the earth

Color is an essential element of human visual perception, which exists in all aspects of our daily lives and plays a key role in scientific research and technological applications. Color is produced by various mechanisms, including absorption and reflection of chemical pigments, complex formation of transition metal ions, and micro- and nanostructural modulation of structural colors. This paper aims to comprehensively explore the scientific principles of color generation and its applications in different fields. The article first describes how transition metal ions exhibit colors by forming complexes and explains in detail the coordination process of copper ions in an aqueous solution and its resulting d-orbital splitting, which in turn absorbs light of specific wavelengths and exhibits complementary colors. Secondly, the article explores the mechanism of color expression of natural pigments in plants, significantly how pigment molecules containing conjugated double bonds, such as -carotene, can absorb specific wavelengths of light and exhibit vivid colors through electron delocalization and energy level jumps. Finally, the article illustrates the principles of structural color and its potential for industrial applications, including using micro- and nanostructures, such as photonic crystals, to modulate the scattering and absorption of light, thus enabling dynamic changes in color and environmental protection. The in-depth exploration of the mechanism of color generation enhances our understanding of the basic principles of color science. It provides theoretical support for technological innovation and practical applications in related fields.

Comparative Evaluation of Surface Roughness and Color Stability of Polyetheretherketone with Conventional Interim Prosthetic Materials: An In Vitro Study.

The aim of this in vitro study was to compare the surface roughness and color stability of polyetheretherketone (PEEK) with those of conventional interim prosthetic materials like polymethylmethacrylate, bis-acrylic composite, and rubberized diurethane dimethacrylate, following immersion in solutions of varying pH value. A total of 320 circular discs with 10 mm diameter and 2 mm height were divided based on the fabrication (n = 80)-group A: polymethylmethacrylate; group B: bis-acrylic composite; group R: rubberized diurethane; and group P: hot-pressed PEEK-and were subjected to baseline measurement of roughness (n = 40) and color (n = 40) using 3D profilometer and UV-Vis spectrophotometer, respectively. Later, 10 samples from each group were immersed in distilled water, black coffee, green tea, and Pepsi, respectively, for 120 days, and measurements of roughness and color were repeated. The differences in roughness (ΔRa) and color change(ΔE) were calculated and statistically analyzed with a significance level of p-value < 0.05. Irrespective of the immersion solution, the highest mean difference in the roughness values was shown by rubberized diurethane specimens: ΔRa = 3.574880 (0.0048350) in carbonated beverages, and lowest difference was shown by bis-acrylic composite: ΔRa = 0.29004 (0.0017473) in distilled water. The greatest color stability was exhibited by PEEK. The type of interim material and immersion solution had a statistically significant effect on change in color and roughness values. The immersion in solutions of varying pH had a significant effect on surface roughness and color stability of all the tested materials. The Ra value of all specimens after immersion was still within the clinically acceptable range. Polyetheretherketone was the most color stable material in all solutions, except in green tea. This study will provide guidance to dentists and patients regarding the selection of interim material for long-term use, depending on the effect of beverage consumption on its color stability and roughness. How to cite this article: Saraswathy A, Latha N, Ayyadanveettil P, et al. Comparative Evaluation of Surface Roughness and Color Stability of Polyetheretherketone with Conventional Interim Prosthetic Materials: An In Vitro Study. J Contemp Dent Pract 2024;25(10):930-935.

Conservation Analysis and Colorimetric Characterization of Betalain Extracts from the Peel of Red Beetroot, Golden Beetroot, and Prickly Pear Applied to Cottage Cheese.

The maintenance of betalains and the color of extracts from the peel of red beetroot (RBAC), golden beetroot (YBAC), and purple prickly pear (PBAC) were evaluated, describing the capacity of their use as natural pigments and in the formulation of attractive and functional foods. Betalain extracts were prepared as juices from frozen and dehydrated peel, adding organic acids and concentrating for water reduction. Extracts were evaluated and applied on cottage cheese, measuring the capacity of betalains retention and pigmentation, during 10 days of storage of closed and opened products. Extracts of RBAC showed the highest betacyanin concentration, followed by YBAC with betaxanthins and PBAC with less betacyanin content. The pH stability for the extracts was pH4-7; RBAC and PBAC were stables at <90 °C, whereas YBAC exposed >125 °C. Extracts were constant during 10 days under oxygen and light exposure; however, YBAC exhibited low resistance in this environment. With cottage cheese, extracts exposed no changes in betalains and color on closed products (10 days of storage at 4 °C). In opened products, PBAC maintained the maximum betalains and color at 90%, PBAC at 75%, and YBAC at 60%. The obtained data contributed to use of agro-industrial residues, betalain extraction and conservation, and their potential use in food coloration and stabilization.

Effects of Light Intensity and Irrigation Method on Growth, Quality, and Anthocyanin Content of Red Oak Lettuce (Lactuca sativa var. cripspa L.) Cultivated in a Plant Factory with Artificial Lighting

Cultivating red oak lettuce in plant factories often encounters challenges in achieving the desired red leaf coloration. To make the leaves a pleasant red color, anthocyanins are key substances that need to be induced. This study aimed to evaluate the effects of increasing light intensity and irrigation methods on the growth and leaf color of red oak lettuce in a controlled environment. Two light intensities (300 and 400 µmol m−2 s−1) with white LEDs and two irrigation methods (circulating vs. non-circulating irrigation) were applied seven days before harvesting. The results indicated that plants grown with circulating irrigation exhibited significantly higher fresh and dry weights than those grown under non-circulating conditions, regardless of light intensity. When non-circulating irrigation was applied, shoot fresh weight decreased by approximately 22% on the harvesting day compared to the circulating treatments. Under the 400 µmol m−2 s−1 light intensity with non-circulating irrigation (400N-C), plants displayed the lowest lightness (L*) at 40.7, increased redness (a*) to −7.4, and reduced yellowness (b*) to 11.0. These changes in coloration were optimized by day 5 after treatment. Additionally, spectral indices, including normalized difference vegetation index and photochemical reflectance index, varied significantly among treatments. The 400N-C treatment also resulted in the highest anthocyanin content and antioxidant activity in red oak lettuce. These findings suggest that combining high light intensity with non-circulating irrigation before harvest can improve both the coloration and quality of red oak lettuce in plant factories with artificial lighting.

Combustion and emission characteristics of ammonia/methane partially premixed flame under ultrasonic excitation

ABSTRACT Ammonia (NH3) is emerging as a promising alternative fuel due to its high energy density and non-carbon mature. However, its large-scale industrial application is limited by its low reactivity and high nitrogen oxide (NOx) emissions during combustion. This paper investigated the effect of ultrasonic excitation on the combustion and emission characteristics of ammonia-methane-air partially premixed flame in a laboratory-scale burner. The flame temperature distribution was reconstructed using deflection tomography, and the flue gas composition was measured using a multicomponent gas analyzer. Numerical simulations were also conducted under the same experimental conditions. The experimental results showed that applying various ultrasonic frequencies resulted in a stable flame. The ultrasonic excitation resulted in changes in flame brightness and color, as well as a reduction in nitric oxide (NO) emission. Compared to the case without ultrasonic excitation, the maximum flame temperature increased by 17.85%, and NO emission decreased by 19.04% when excited with 20.2 kHz ultrasonic. The simulation results indicated that ultrasonic excitation enhanced the formation of free radicals. Single-point and rate of production (ROP) analysis further revealed that ultrasonic excitation enhanced the dehydrogenation of NHi and the polymerization between NH2 and NH. Additionally, ultrasonic excitation accelerated the direct reactions between NH and N with NO, leading to the formation of N2.

Integrative Omics Analysis Reveals Mechanisms of Anthocyanin Biosynthesis in Djulis Spikes.

Djulis (Chenopodium formosanum Koidz.), a member of the Amaranthaceae family plant, is noted for its vibrant appearance and significant ornamental value. However, the mechanisms underlying color variation in its spikes remain unexplored. This research initially detected the anthocyanin content at different developmental stages of the spike and subsequently utilized an integrative approach, combining targeted metabolomics, transcriptomics, and untargeted metabolomics analyses, to elucidate the mechanisms of anthocyanin biosynthesis in the spikes of djulis. The results of the combined multi-omics analysis showed that the metabolites associated with anthocyanin synthesis were mainly enriched in the flavonoid biosynthesis pathway (ko00941) and the anthocyanin biosynthesis pathway (ko00942). With the maturation of djulis spikes, a total of 28 differentially expressed genes and 17 differentially expressed metabolites were screened during the transition of spike color from green (G) to red (R) or orange (O). Twenty differentially expressed genes were selected for qRT-PCR validation, and the results are consistent with transcriptome sequencing. The upregulation of seven genes, including chalcone synthase (CfCHS3_1, CfCHS3_2, CfCHS3_3), flavanone 3-hydroxylase (CfF3H_3), flavonoid 3'5'-hydroxylase (CfCYP75A6_1), dihydroflavonol reductase (CfDFRA), and glucosyltransferase (Cf3GGT), promotes the formation and accumulation of delphinidin 3-sambubioside and peonidin 3-galactoside. The research results also showed that anthocyanins and betalains can coexist in the spike of djulis, and the reason for the change in spike color during development may be the result of the combined action of the two pigments. A possible regulatory pathway for anthocyanin biosynthesis during the spike maturation was constructed based on the analysis results. The results provide a reference and theoretical basis for further studying the molecular mechanism of anthocyanin regulation of color changes in Amaranthaceae plants.

UVB Induces Sympathetic Nervous System Activation and Norepinephrine Secretion to Regulate TheSkin Color of Mice Through the β2-AR/AP-1 Pathway in Epidermal Keratinocytes.

The aim of this study was to investigate how ultraviolet B (UVB) light regulates AP-1 expression via the β2-adrenergic receptor (β2-AR) in epidermal keratinocytes, which in turn regulates melanin synthesis in melanocytes, thereby modulating downstream melanin production in skin hair follicles and altering mouse skin color. We established a UV-irradiated mouse model to investigate the effects of UV radiation on changes in skin color. By measuring changes in the expression of genes related to cutaneous sympathetic nerves, norepinephrine synthesis and melanin synthesis, we investigated the relationship between β2-AR expression and cutaneous melanogenesis and determined the localization of β2-AR in cells. The results of the siRNA-mediated transfection of keratinized cells with downregulated β2-AR expression were further verified in vitro. Our results suggest that UVB alters the color of the dorsal skin in mice by activating the AP-1/IL-6 pathway, which triggers the sympathetic release of norepinephrine, thereby increasing β2-AR expression in keratinocytes. Overall, our study improves the current understanding of how UVB light influences skin color changes and highlights the complex interplay between ultraviolet radiation and skin physiology.

Evaluation of Workplace Online CB-ART Interventions for Reducing Disaster-Related Distress

Research suggests that the workplace is an effective platform for delivering disaster interventions, highlighting the benefits of implementing early and brief post-disaster interventions both within and outside of workplace settings. This pilot study sought to expand empirical knowledge of a unique brief disaster intervention—the single-session cognitive behavioral and art-based (CB-ART) intervention—by exploring its online use in a workplace setting during wartime conditions. In this single-session intervention, 12 employees sequentially drew three images: their disaster-related stress, their resources, and an integration of these. The aims of the study were to (1) identify the strategies participants employed to mitigate their distress, as evidenced by their drawings and accompanying narratives; (2) assess whether participants experienced a significant reduction of distress levels post-intervention; and (3) explore the resources utilized by participants after the intervention. Results highlight participants’ compositional transformations of the stressful image, including changes in size, color, and placement within the integrative drawing, which enabled them to modify its emotional content. Further support for the significance of the CB-ART intervention is evident in the significant decrease in participants’ distress levels after the intervention, measured by the Subjective Units of Distress Scale, as well as in the illustrative examples of the resources used several months post-intervention. On a practical level, our study offers a tool that can be easily implemented online during disaster times, ensuring that workplace support remains accessible despite disruptions. Our findings may encourage health policymakers to consider workplace settings as valuable platforms for disaster interventions, thereby conserving resources needed during crises.

Preparation and Efficacy of Microemulsion Carvacrol-Based Fruit and Vegetable Cleaner and Its Application on Cherry Tomatoes.

Carvacrol, a natural plant compound with antibacterial, antioxidant, and various biological activities, serves as the basis for developing a micro-emulsion fruit and vegetable cleaner. The study found that carvacrol demonstrated a minimum inhibitory concentration (MIC) ranging between 0.25 and 0.5 mg/mL against four foodborne pathogenic bacteria and three spoilage fungi. The formulated cleaner, containing 67 mg/mL of carvacrol, demonstrated superior characteristics (a particle size of 228 nm, an absolute zeta potential of 21.4 mv, and a stability coefficient of 91.2%). Remarkably, the cleaner remained stable when stored at room temperature for at least 3 months. Its efficacy against pesticides ranged from 76% to 91%. The cleaning effectively inhibited microbial colonies and the decay rate of cherry tomatoes during storage at 4 °C. Furthermore, the cleaning treatment was found to minimize changes in color and hardness. Overall, this study provides evidence that a fruit and vegetable cleaner based on carvacrol enhances the safety of the food industry effectively.

Unveiling the Dissociation Mechanism of Diglycine Perchlorate.

Determining the dissociation mechanism of perchlorate materials remains a top priority to address sustainability, handling, processing, and synthesis issues of new and existing high-energy density materials vital to many industrial processes. We determined the dissociation mechanism of diglycine perchlorate (DGPCl) using vibrational spectroscopy, which unveiled the formation of ammonium perchlorate (AP) and carbon at high temperatures. Our studies establish that DGPCl shows multiple phase transitions upon heating. The reversible melting transition (∼100 °C) is characterized by reorientations in hydrogen bonding, thereby modifying glycine geometry. The irreversible liquid-liquid transition (∼170 °C) is guided by the dissociation of cationic glycine and the formation of an intermediate complex, showing a change in color. Above 240 °C, the liquid state transforms to a solid state with the evolution of H2O, HCN, CO, CH4, N2O, CO2, etc., gases, detected using high-resolution rovibrational and mass spectroscopy. Notably, no NH3 release was observed, ruling out an earlier prediction. This results in the formation of AP, one of the strongest oxidizers, as residue enveloped by carbon layers, a potential fuel. The observed exothermic enthalpy above 240 °C is ∼405 kJ/mol. The discovery may pave the way toward finding better organic perchlorates with modified properties to mitigate challenges with the existing ones.

Impact of Harsh Grinding on the Structure and Color of LiCoPO4 and LiNiPO4 Pigments.

LiCoPO4 and LiNiPO4 phosphate pigments have colorations very close to the primary colors of the subtractive system: magenta and yellow, respectively. These two pigments are therefore of great interest in a variety of applications, including e-reader devices. However, the need to reduce their crystallite size in order to formulate stable electrophoretic inks has revealed that aggressive milling results in significant color changes, particularly for cobalt-based pigments. Here, we elucidate the origin of this phenomenon by carefully examining the structural changes induced by grinding, utilizing a combination of X-ray diffraction pattern refinement, molecular dynamics simulations, and UV-visible near-infrared, EPR, and NMR spectroscopies. Structural distortion near the crystallite surfaces was shown to be responsible for the change in coloration. As the surface-to-volume ratio increases with a decreasing crystallite size, these atomic reorganizations in the first few atomic layers close to the surface become increasingly significant and even critical for sample coloration.

Efficacy of Air and Oxygen Micro-nano Bubble Waters Against Colletotrichum gloeosporioides and Impacts on Postharvest Quality of 'Fan Retief' Guava Fruit.

This study focused on the application of micro-nano bubbles (MNBs) water generated using air or oxygen (O2), as an alternative to chlorine-based wash for fruits. For the in vitro and in vivo investigation, 106 spore or conidia/mL Colletotrichum gloeosporioides suspension was used, and treated with solutions of air- or O2-MNB for 30- or 60-min, sodium hypochlorite (NaOCl), and untreated (as control). In the second experiment, freshly harvested guava fruits were washed with tap water (control), NaOCl (standard practice), air-, or O2-MNB (for 15- or 30-min). All samples were packaged, stored for 21 days at 13 °C, and monitored for changes in natural microbial population and quality attributes. Based on the confocal laser and transmission electron microscopy results, exposure of C. gloeosporioides to air-MNB for 60 min resulted in the lowest viable cell count (%) compared to control and other treatments (O2-MNB and NaOCl). Air- and O2-MNB treatments damaged cellular structures, disrupted cell membrane integrity, and deformed hyphal morphology. Washing 'Fan Retief' guava (Psidium guajava L.) in air- or O2-MNB (for 15 and/or 30 min), better-retained tissue strength, delayed changes in color, and total soluble solid (TSS) content. Notably, MNB treatments were as effective as NaOCl washing and significantly reduced microbial load on fruit surface by ≥2 Log (p < 0.05). Micro-nano bubble water treatment offers a new paradigm for decontamination and preservation of guava fruit quality.