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The shortage of superior grade wood fibers is a prime problem faced by Indian pulp and paper industries. As a result, the pulp and paper industry find it difficult to withstand the competition in the market, which had grown extremely competitive. In order to increase the utilization of non-wood fibers resources in the production of high quality eco-friendly papers, dhaincha, a non-wood fiber resource has potential industrial application. In this research, pulp and paper were developed from Sesbania aculeata stem using kraft pulping followed by bleaching. Optimization of conditions for pulping was carried out by Response Surface Methodology. The relationship between three variables and three responses were studied using Box–Behnken experimental design. The developed pulp was evaluated for kappa number, brightness index, viscosity, FTIR and TGA. Then paper was developed by using optimized pulp and evaluated for physical properties. The statistical analysis (ANOVA) was carried out in order to establish the relationship between the concentration of NaOH, Na2S, treatment time and temperature with kappa number, brightness index and viscosity. The physical properties of pulp and developed handmade paper highlights the sustainable use of dhaincha plant in pulp and paper industry. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates the role of secondary condensates in the pulp and paper industry's journey to minimize its water footprint. The integration of secondary condensates, traditionally less explored in bleaching processes, is examined for its potential in reducing freshwater demand. Condensates with different organic content (chemical oxygen demand, COD) and their mixtures were tested as washing liquid after the alkaline extraction stage (EP) of eucalyptus globulus kraft pulp and compared to hot water. Two subsequent chlorine dioxide stages were applied to evaluate the impact of the washing liquid COD on pulp properties and chemicals consumption. Despite its higher organic content, the condensates can be used as a partial or total substitute for hot water without substantial compromises in the pulp properties, such as brightness, reversion, and viscosity. The calculated correlation between ClO2 consumption and COD in the washing liquid can be applied for assessing economic and environmental trade-offs, providing a roadmap for optimizing processes and reducing environmental impacts. [ABSTRACT FROM AUTHOR]

The use of cyclodextrins in textiles for the development of biofunctional fabrics represents an interesting alternative for the advancement of dental, medical, and hospital materials. Cyclodextrins can interact with the chemical groups present in cotton fibers, leading to the formation of a nanostructured surface with specific functional properties, including antibacterial activity. Although there are numerous antibacterial textile finishes, the use of methylene blue as a cyclodextrin host molecule for photodynamic applications in textile materials remains to be investigated. This is because methylene blue is a photosensitive dye capable of generating singlet oxygen (1O2) when illuminated, which inactivates the pathogenic microorganisms that may be present in wounds. The objective of this study was to develop a biofunctionalized and photoactivatable cotton fabric with antimicrobial properties for use in the cosmetic or medical industries. The materials obtained were characterized via scanning electron microscopy (SEM), Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), the determination of cotton fabric functionalization dyeing variables, colorimetry, UV-VIS spectrophotometry, degradation of 9,10-anthracenediyl-bis(methylene)dimalonic acid (ABDA), photodegradation tests, and microbiological analysis. The results showed that the textile was functionalized with β-cyclodextrin, mainly evidenced by the appearance of the band at 1730 cm−1, indicating the formation of the ester group. Thus, when exposed to light, the non-functionalized material showed greater photobleaching, about 60%, compared to the material treated with cyclodextrin. This result was also reflected in the ABDA degradation kinetics, with the treated material showing 592.00% (first phase) and 966.20% (second phase) higher degradation than the untreated sample. Finally, the photodynamic activity was determined based on the antimicrobial properties of the textile, showing a reduction of more than 99% without exposure to light and 100% when exposed to light. It is believed that this study could open avenues for future research and the development of antimicrobial fabrics, as well as demonstrate the efficiency of the treatment with cyclodextrin in relation to photobleaching. [ABSTRACT FROM AUTHOR]

Ultrafast transient vibrational action spectra of cryogenically cooled Re(CO)3(CH3CN)3+ ions are presented. Nonlinear spectra were collected in the time domain by monitoring the photodissociation of a weakly bound N2 messenger tag as a function of delay times and phases between a set of three infrared pulses. Frequency-resolved spectra in the carbonyl stretch region show relatively strong bleaching signals that oscillate at the difference frequency between the two observed vibrational features as a function of the pump–probe waiting time. This observation is consistent with the presence of nonlinear pathways resulting from underlying cross-peak signals between the coupled symmetric–asymmetric C≡O stretch pair. The successful demonstration of frequency-resolved ultrafast transient vibrational action spectroscopy of dilute molecular ion ensembles provides an exciting, new framework for the study of molecular dynamics in isolated, complex molecular ion systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agroindustrial Technology / Jurnal Teknologi Industri Pertanian is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The increase in styrofoam waste can cause environmental pollution, therefore efforts are required to reduce the use of styrofoam. One of them is by replacing it with biofoam made from agricultural industry waste such as bagasse because if this garbage is not used, it may cause environmental issues. Bagasse has a potential to be utilized as biofoam. This research aims to extract cellulose from bagasse through delignification and bleaching processes, as well as synthesize and characterize biofoam using cellulose from bagasse with the addition of chitosan variations of 2, 3.5, 5, and 6.5 g. The stages of this research are the extraction of cellulose from bagasse waste with FTIR and XRD analysis, making biofoam and biofoam characterization tests. The results of cellulose extraction from bagasse are O-H, C-H and C-O functional groups that indicate the presence of cellulose. In XRD analysis, the cellulose sample has a crystallinity index of 70.74%. Biofoam based on sugarcane bagasse cellulose with the addition of 2 g chitosan has the best characterization, which has a density of 1.23 g/mL, with a water absorption value of 46.03% at 24 hours immersion and biodegradability of 20.68% for 28 days. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study is to investigate the use of 15% carbamide peroxide in combination with fluoro calcium phosphosilicate desensitizing dentifrice during bleaching to evaluate postoperative dentinal tubule occlusion. Materials and Methods: Premolars which were extracted and bleached using 15% carbamide peroxide with fluoro calcium phosphosilicate dentifrice were used in this investigation, and the shade change was assessed. They were subsequently divided into sections and examined with scanning electron microscope. The quantity of open tubules, fully obstructed as well as moderately obstructed tubules, was recorded for each specimen. The statistical analysis of shade changes was conducted using the paired t-test. The tubule numbers were statistically evaluated after being assigned a mean and standard deviation. Results: The mean values between test and control groups in completely blocked tubules are 81.370 ± 1.989 and 42.586 ± 11.316, respectively. In partially blocked tubules, the mean values were found to be 13.219 ± 1.747 and 32.264 ± 11.554, respectively. In open tubules, the mean values are 5.398 ± 1.260 and 25.149 ± 8.781. The mean values of shade comparison for test group and control group are 1.95 ± 2.78 and 3.40 ± 2.83, respectively. Conclusions: According to the findings of the study, dentinal tubules were blocked when fluoro calcium phosphosilicate dentifrice was administered with 15% carbamide peroxide, but the bleaching process was unaffected. The potential clinical advantage of using a single paste system for both bleaching and desensitizing was also emphasized. [ABSTRACT FROM AUTHOR]

Granulated truck waste tire was first pyrolyzed in a fixed‐bed reactor under an inert atmosphere and at certain conditions. The highest oil yield of which was 47.0 wt %, was attained at 550 and 20°C/min. The oil was separated into a fraction of 150–300°C boiling points, so‐called diesel‐like fuel (DBY), with a calcium oxide (CaO) catalyst at an optimal ratio of 2 wt %. The fraction was subjected to desulfurization, bleaching, and deodorization, respectively, at specific conditions, and this process resulted in a decrease of 75.8 wt % compared to its initial sulfur content of 5000 ppm. The upgraded diesel‐like oil (DAF) fraction contained chemical compounds with carbon numbers C6–C26. In addition, its physicochemical characteristics showed a kinematic viscosity of 3.13 cSt (40°C), a density of 832 g/L (15°C), a lower heating value of 42.32 MJ/kg, and an H/C molar ratio of 1.73. Lastly, the DAF was tested with commercial diesel fuel for its motor and emission performance via a single‐cylinder diesel engine. All in all, it can be said that the DAF may be harnessed as a substitute for diesel fuels after its further upgrading via catalytic hydrodesulfurization etc. [ABSTRACT FROM AUTHOR]

Introduction: Hydrogen peroxide for bleaching procedure, can penetrate the interprismatic space of enamel and dentin tubules, leading to pulp irritation. Oxidative stress resulting from this irritation triggers an inflammatory reaction in the pulp, increasing the number of macrophage cells. One approach to mitigate the cytotoxic effects of bleaching agents diffusing is the application of antioxidants. Green tea contains numerous catechins known for their antioxidant activity. This study aims to investigate the impact of applying green tea extract gel (Camellia sinensis) at concentrations of 5% and 10% on macrophage cell count in the tooth pulp of Wistar rats' after an extra coronal bleaching procedure using 40% hydrogen peroxide. Materials and methods: Fifteen upper molars from Wistar rats' divided into three groups. The control group underwent the bleaching procedure alone. The teeth were rinsed in the control group with warm distilled water, while the first group received 5% and second group received 10% green tea extract gel. On the 5th day, molar specimens were collected and prepared for histological examination using hematoxylin-eosin (HE) staining. Macrophage cell counts were calculated using a light microscope at 400x magnification. Results: The Results of one-way ANOVA test revealed a significant influence of green tea extract concentration on macrophage cell count (p < 0.05). LSD post hoc test indicated significant differences in all compared groups. Conclusion: Application of 10% green tea extract concentration resulted in a lower macrophage cell count compared to both the 5% concentration and the control group. [ABSTRACT FROM AUTHOR]

Plant fibers have been studied as sources of nanocellulose due to their sustainable features. This study investigated the effects of acid hydrolysis parameters, reaction temperature, and acid concentration on nanocellulose yield from maguey (Agave cantala) fiber. Nanocellulose was produced from the fibers via the removal of non-cellulosic components through alkali treatment and bleaching, followed by strong acid hydrolysis for 45 min using sulfuric acid (H2SO4). The temperature during acid hydrolysis was 30, 40, 50, and 60 °C, and the H2SO4 concentration was 40, 50, and 60 wt. % H2SO4. Results showed that 53.56% of raw maguey fibers were isolated as cellulose, that is, 89.45% was α-cellulose. The highest nanocellulose yield of 81.58 ± 0.36% was achieved from acid hydrolysis at 50 °C using 50 wt. % H2SO4, producing nanocellulose measuring 8–75 nm in diameter and 72–866 nm in length, as confirmed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Fourier-transform infrared spectroscopy (FTIR) analysis indicated the chemical transformation of fibers throughout the nanocellulose production process. The zeta potential analysis showed that the nanocellulose had excellent colloidal stability with a highly negative surface charge of −37.3 mV. Meanwhile, X-ray diffraction (XRD) analysis validated the crystallinity of nanocellulose with a crystallinity index of 74.80%. Lastly, thermogravimetric analysis (TGA) demonstrated that the inflection point attributed to the cellulose degradation of the produced nanocellulose is 311.41 °C. [ABSTRACT FROM AUTHOR]

Organic photothermal materials have attracted increasing attention because of their structural diversity, flexibility, and compatibility. However, their energy conversion efficiency is limited owing to the narrow absorption spectrum, strong reflection/transmittance, and insufficient nonradiative decay. In this study, two quinoxaline‐based D–A‐D–A‐D‐type molecules with ethyl (BQE) or carboxylate (BQC) substituents were synthesized. Strong intramolecular charge transfer provided both molecules with a broad absorption range of 350–1000 nm. In addition, the high reorganization energy and weak molecular packing of BQE resulted in efficient nonradiative decay. More importantly, the self‐assembly of BQE leads to a textured surface and enhances the light‐trapping efficiency with significantly reduced light reflection/transmittance. Consequently, BQE achieved an impressive solar‐thermal conversion efficiency of 18.16 % under 1.0 kW m−2 irradiation with good photobleaching resistance. Based on this knowledge, the water evaporation rate of 1.2 kg m−2 h−1 was attained for the BQE‐based interfacial evaporation device with an efficiency of 83 % under 1.0 kW m−2 simulated sunlight. Finally, the synergetic integration of solar‐steam and thermoelectric co‐generation devices based on BQE was realized without significantly sacrificing solar‐steam efficiency. This underscores the practical applications of BQE‐based technology in effectively harnessing photothermal energy. This study provides new insights into the molecular design for enhancing light‐trapping management by molecular self‐assembly, paving the way for photothermal‐driven applications of organic photothermal materials. [ABSTRACT FROM AUTHOR]

The survey aimed to investigate the adsorption properties of cellulose-based materials derived from cereal by-products towards Ag+ ions in water solutions, and to shed light on the mechanism of adsorption. Cellulose was isolated from rice and einkorn husks using alkali and bleaching treatments. Untreated einkorn husks and commercial cellulose served as reference samples. Characterization techniques included XRD, FTIR, SEM, and low-temperature nitrogen adsorption, with surface elemental composition analyzed by XPS. The study examined how contact time, initial silver ion concentration, pH, and temperature affected adsorption. The adsorption process was modeled using pseudo-second-order and Langmuir models, and thermodynamic parameters were evaluated. All materials showed potential as effective Ag+ ion adsorbents, indicating their suitability for creating silver-modified catalytic materials. [ABSTRACT FROM AUTHOR]

This study reported the isolation of cellulose from corn cob by using microwave-assisted alkaline treatment and bleaching. The Central Composite Design (CCD) approach of Response Surface Methodology (RSM) was applied to study the effect of sodium hydroxide (NaOH) concentrations (1.5-2.5M), duration of alkaline treatment (4-8 min), hydrogen peroxide (H2O2) concentrations (7-9 wt%) and bleaching time (3-7 min) on the removal percent of non-cellulosic components and impurities from corn cob. The optimized conditions obtained from this study were 2.37M NaOH, 9 wt% H2O2, alkaline treatment time of 4 min, and bleaching time -- 4.20 min. The non-cellulosic part and the impurities removed under the optimized conditions in microwave-assisted alkaline treatment and bleaching amounted to 72.26 ± 0.15%. The cellulose content in the thus purified corn cob material was determined as 92.47%. The isolated corn cob cellulose was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and the thermogravimetric analysis (TGA). These characterizations confirmed that the alkaline treatment and microwave-assisted bleaching under the optimized conditions achieved the optimal removal percent of the non-cellulosic components and impurities from the corn cob biomass to achieve highly purified cellulose. [ABSTRACT FROM AUTHOR]

Cellulose is one of the most abundant biopolymers on Earth and is of most significant interest due to its properties and uses. Cellulose can be obtained from agro-industrial residues, such as rice husk, whose cellulose content is approximately 30%. In this study, cellulose microfibers were extracted from rice husks. Fibers were obtained by submitting the biomass to alkali (NaOH) and bleaching treatments. These treatments have already been reported in the literature; however, variables such as the concentration of reagents, the time, and the temperature of the chemical treatment have yet to be optimized. A factorial design of experiments with 3 factors and 2 levels for each factor was proposed to optimize the chemical processes. It was determined through the analysis of variance (ANOVA) that the factors evaluated significantly influenced the elimination of non-cellulosic compounds, and that the chemical treatment was more efficient when the factors took high level values. Ultraviolet-visible spectroscopy (UV-Vis) analysis showed the successful removal of undesired components during the alkaline treatment. The effect of the treatments on the morphology upon removing hemicelluloses, lignin, and inorganic material was evaluated through Scanning Electron Microscopy (SEM). The increase in the thermal stability in the alkali-treated rice husk and in cellulose microfibers, compared to the raw rice husk, was established by thermogravimetric analysis (TGA). X-ray diffraction (XRD) indicated that the treatments increased the percentage of crystallinity. [ABSTRACT FROM AUTHOR]

This article discusses the use of dermoscopy, a diagnostic tool, to evaluate the efficacy of treatment for facial port-wine stains (PWS). The study included 61 patients with untreated facial PWS who underwent photodynamic therapy. The researchers used dermoscopy to quantify the efficacy of the treatment by analyzing vessel density and color improvement. They found that vessel density positively correlated with the color of PWS, and changes in vessel density could be used to reflect changes in PWS color. The accuracy and reliability of dermoscopy assessment were compared to visual and colorimeter assessments, and dermoscopy assessment was found to be more consistent with visual assessment, suggesting it may be more suitable for people of East Asian descent. [Extracted from the article]

Background In the current cosmetics industry, bleaching is often associated with lasers. However, such treatment also harbors risks. Tooth death is observed at pulpal temperature increases ≥5.6 °C. Therefore, it seems important to investigate the effects of using different lasers. The aim of this study was to determine pulpal temperature increases at different laser parameters during bleaching by modeling a realistic environment and to compare the temperature recording using a thermocouple and thermal camera. The authors assumed that there are laser settings for the lasers used at which the pulpal temperature increases are <5.6 °C and that the temperature recordings with thermocouples and thermal cameras differ only minimally. Methods Human teeth were used, which were extracted for dental reasons. During experiment, teeth were bleached conventionally and by laser activation at 940 nm, 445 nm, and 970 nm. The temperature in the pulp was recorded using thermocouples. In a second setup, longitudinally halved teeth were bleached, while the temperature in the pulp was recorded with a thermocouple and thermal camera. Descriptive statistics were used. The significance level is 0.05. Results In addition to conventional bleaching, temperature increases <5.6 °C were observed for bleaching at 940 nm 1.5 W, at 445 nm 0.3 W, and at 970 nm 0.5 W. For bleaching procedures using 940 nm 7 W, 940 nm 2 W, 445 nm 0.5 W, and 970 nm 1 W, the temperature increase was ≥5.6 °C. Significant differences (p < 0.05) were found in the maximum temperature increases (°C) between all groups. Temperature recordings using a thermocouple and thermal camera differed by about 2.3 °C. The working hypotheses were confirmed. Conclusion With laser bleaching, attention must be paid to the type of laser, its power, and the time in order to avoid excessive overheating of the dental pulp. [ABSTRACT FROM AUTHOR]

This study demonstrates a novel methodology for developing a textile-based adsorption sensor via mixed solvent dyeing with aggregation-induced emission (AIE) dyes on recycled fabrics. AIE dyes were incorporated into the fabrics using a mixed solvent dyeing method with a co-solvent mixture of H2O and organic solvents. This method imparted unique fluorescence properties to fabrics, altering fluorescence intensity or wavelength based on whether the AIE dye molecules were in an isolated or aggregated state on the fabrics. The precise control of the H2O fraction to organic solvent during dyeing was crucial for influencing fluorescence intensity and sensing characteristics. These dyed fabrics exhibited reactive thermochromic and vaporchromic properties, with changes in fluorescence intensity corresponding to variations in temperature and exposure to volatile organic solvents (VOCs). Their superior characteristics, including a repetitive fluorescence switching property and resistance to photo-bleaching, enhance their practicality across various applications. Consequently, the smart fabrics dyed with AIE dye not only find applications in clothing and fashion design but demonstrate versatility in various fields, extending to sensing temperature, humidity, and hazardous chemicals. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to conduct a systematic review and meta-analysis to determine the necessity of a white diet during or following a bleaching procedure. This systematic review and meta-analysis followed the PRISMA guidelines meticulously. The research question was: Is a white diet necessary during and/or after a bleaching treatment? In vitro studies or clinical trials reporting the color change in bleached enamel after the use of a free-staining diet were considered for full-text review. For the analyses, a random-effects model was employed. Statistical significance was defined as a p-value < 0.05. A total of 17 documents were eligible for qualitative analysis: 5 clinical trials and 12 in vitro studies. Only data from the clinical trials were included in the meta-analysis. For at-home bleaching, differences in the color among the subjects were not statistically significant during the first (p = 0.64), second (p = 0.26) or third (p = 0.43) weeks of treatment. Also, the color difference one month after finishing the bleaching treatment were not statistically significant (p = 0.27). The color difference one month after finishing an in-office treatment showed that the restrictions on diet did not significantly improve the bleaching outcomes (p = 0.90). According to the findings of this review, dietary restrictions are not necessary during or after bleaching procedures. [ABSTRACT FROM AUTHOR]

Litchi is prone to deterioration in quality after harvest due to degradation of anthocyanins and respiratory metabolism, and chlorine dioxide (ClO2) has multiple effects on color protection and respiratory inhibition. In this study, 0.1 g (T1), 0.4 g (T2), and 1.2 g (T3) of ClO2 slow-releasing preservatives were used to treat lychees with 0 g (CK) as the control to evaluate the preservation effect by quality index, color index and anthocyanin, and correlation analysis was applied to explore the association between them. The results showed that the litchi of the T1 showed the optimal qualities. On the 7 th day, the total soluble solids and a* values of litchi in the T1 were significantly (P<0.05) increased by 2.93% and 10.13%, respectively, while the respiration rate was significantly (P<0.05) decreased by 34.54% compared to the CK group in the same period. On the contrary, the relative conductivity of the T3 litchi reached the highest value of 35.84% on the 7 th day, and a* decreased to the lowest value of 18.38, indicating significant damage to cell structure, bleaching, and the worst storage quality. To further investigate the relationship between color changes and anthocyanins, 10 key anthocyanins were selected from litchi, including 7 proanthocyanins, which accounted for 66.96% of the total. The correlation analysis showed that the correlation coefficients between a* value and cyanidin-3-O-galactoside in the T1, T2, and T3 groups were 0.980, 0.548, and 0.360, respectively, and the correlation coefficients with cyanidin-3-O-glucoside were 0.985, 0.488, and 0.402 during storage. The T1 maintained the best color, possibly due to the slower decomposition of the two key red anthocyanins above, while the T3 accelerated the decomposition of anthocyanins. This study could provide valuable insights for enhancing the postharvest quality of litchi. [ABSTRACT FROM AUTHOR]

The sol–gel process for fabricating electrochromic thin films is straightforward, offering advantages such as low cost and ease of compositional control. Herein we prepared GO–Bi–WO3 films with improved electrochromic performance using a simple sol–gel spin-coating method. The sample shows a fast-switching time (1.8 s for coloring and 1.8 s for bleaching), large optical modulation (85% at 630 nm), excellent stability (86.4% retention after 10 200 cycles), and high coloration efficiency (65.9 cm2 C−1). This work indicates the electrochromic performance of WO3-based films can be enhanced by incorporating GO, which provides an effective strategy for the rapid, safe, and efficient fabrication of electrochromic thin films. [ABSTRACT FROM AUTHOR]

Crude Palm Oil (CPO) contains approximately 50% saturated fatty acids and approximately 40% unsaturated fatty acids. Unsaturated fatty acid content is known to be effective in lowering blood cholesterol levels. Palm oil also contains bcarotene which is very beneficial for health. Palm oil processing is defined by three stages, namely degumming, bleaching and deodorization. The bleaching process is carried out at 90–105oC using 1-2% bleaching earth and deodorization at 240- 270oC. The high concentration of bleaching earth and deodorization temperature causes carotene to be degraded leading to low carotene content in the final product. The effort to maintain the carotene content is to process CPO into red palm oil (RPO). The content of carotene and fatty acids contained therein will be damaged in the presence of high heat, ascertain this, a study was conducted on the effect of heating time on the chemical properties of red palm oil. The study was conducted using a completely randomized block design with prolonged heating treatment (0, 2, 4, 6, 8 and 10 hours) at 180oC and repeated 3 times and then the fatty acid content, peroxide value, iodine number and functional groups formed in bulk red palm oil purchased online were observed. The results showed that increasing the heating time can decrease the iodine number but increase the acid number and peroxide value. Heating at 180oC for 10 hours produced iodine, acid and peroxide value of 57.72, 9.56 and 12.55, respectively. The results of the analysis using Fourier Transform Infra-Red (FTIR) showed the presence of free fatty acids at wave number 722 cm-1 and peroxide numbers at wave number 2.854 cm-1. The test results using gas chromatography showed that linoleic acid decreased by about 3.23% during heating for up to 10 hours, while saturated fatty acids increased by about 0.32%. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) has emerged as a versatile and environmentally friendly oxidant, showing wide applications in diverse sectors such as fine chemical synthesis, waste stream treatment, precious metal extraction, and textile bleaching. With an escalating demand, H2O2 has now become one of the most essential chemicals worldwide. Efficient photocatalytic generation of H2O2 from water (H2O) and oxygen (O2) has been a long‐standing challenge, presenting a promising prospect to replace existing production methods. This review presents a framework aimed at achieving highly efficient and continuous H2O2 production via photocatalysis. The key aspects include photocatalyst design, selectivity for redox reactions, stability issue and reactor design. Through a comprehensive inspection and comparison of state‐of‐the‐art research, the most viable pathways for H2O2 photogeneration are identified, ensuring optimal solar‐to‐fuel conversion efficiency and high selectivity for target products. The ultimate goal is to establish H2O2 photogeneration as a sustainable and efficient method for producing this valuable chemical, contributing to a greener and more sustainable future. [ABSTRACT FROM AUTHOR]

It is difficult to obtain ultrathin two-dimensional (2D) tungsten trioxide (WO3) nanosheets through direct exfoliation from bulk WO3 in solution due to the strong bonding between interlayers. Herein, WO3 nanosheets with controllable sizes were synthesized via K+ intercalation and the exfoliation of WO3 powder using sonication and temperature. Because of the intercalation and expansion in the interlayer distance, the intercalated WO3 could be successfully exfoliated to produce a large quantity of individual 2D WO3 nanosheets in N-methyl-2-pyrrolidone under sonication. The exfoliated ultrathin WO3 nanosheets exhibited better electrochromic performance in an electrochromic device than WO3 powder and exfoliated WO3 without intercalation. In particular, the prepared small WO3 nanosheets exhibited excellent electrochromic properties with a large optical modulation of 41.78% at 700 nm and fast switching behavior times of 9.2 s for bleaching and 10.5 s for coloring. Furthermore, after 1000 cycles, the small WO3 nanosheets still maintained 86% of their initial performance. [ABSTRACT FROM AUTHOR]

Increasingly frequent marine heatwaves are devastating coral reefs. Corals that survive these extreme events must rapidly recover if they are to withstand subsequent events, and long-term survival in the face of rising ocean temperatures may hinge on recovery capacity and acclimatory gains in heat tolerance over an individual's lifespan. To better understand coral recovery trajectories in the face of successive marine heatwaves, we monitored the responses of bleaching-susceptible and bleaching-resistant individuals of two dominant coral species in Hawai'i, Montipora capitata and Porites compressa, over a decade that included three marine heatwaves. Bleaching-susceptible colonies of P. compressa exhibited beneficial acclimatization to heat stress (i.e., less bleaching) following repeat heatwaves, becoming indistinguishable from bleaching-resistant conspecifics during the third heatwave. In contrast, bleaching-susceptible M. capitata repeatedly bleached during all successive heatwaves and exhibited seasonal bleaching and substantial mortality for up to 3 y following the third heatwave. Encouragingly, bleaching-resistant individuals of both species remained pigmented across the entire time series; however, pigmentation did not necessarily indicate physiological resilience. Specifically, M. capitata displayed incremental yet only partial recovery of symbiont density and tissue biomass across both bleaching phenotypes up to 35 mo following the third heatwave as well as considerable partial mortality. Conversely, P. compressa appeared to recover across most physiological metrics within 2 y and experienced little to no mortality. Ultimately, these results indicate that even some visually robust, bleaching-resistant corals can carry the cost of recurring heatwaves over multiple years, leading to divergent recovery trajectories that may erode coral reef resilience in the Anthropocene. [ABSTRACT FROM AUTHOR]

The ion storage layer in electrochromic devices (ECDs) stores protons or lithium ions to provide electrochemical stability and extend cycle durability. This paper reports on the performance and stability of ECDs paired with various ion storage layers (NiO, V2O5, and IrO2 films). The complementary ECD using a V2O5 ion storage layer presented the fastest response time, but the lowest optical contrast. In addition, the ECD using an IrO2 ion storage layer proved the most effective as an ion storage layer, due to its high optical modulation ability capability and long-term stability. Chronoamperometry analysis revealed that IrO2-based ECD (glass/IZTO/WO3/liquid electrolyte/IrO2/IZTO/glass) can be highly effective in modulating optical transmittance, as indicated by T = 61.5% (from Tbleaching (69.6%) to Tcoloring (8.1%)) and switching times of 5.3 s for coloring and 7.3 s for bleaching at 633 nm. [ABSTRACT FROM AUTHOR]

Terpyridine (TPY) platinum(II) chloride with a triphenylamine (TPA) group was successfully synthesized. The strong intramolecular Donor(TPA)-Acceptor(TPY) interaction induced the low-energy absorption band, mixing the spin-allowed singlet dπ(Pt)→π*(TPY) metal-to-ligand charge transfer (MLCT) with the chloride ligand-to-metal charge transfer (LMCT) and chloride ligand-to-ligand (TPY) charge transfer (LLCT) transitions, to bathochromically shift to λmax = 449 nm with significant enhancement and broadening effects. Using the cyclic voltammetry method, its oxidative electropolymerization (EP) films on working Pt disk and ITO electrodes were produced with tunable thickness and diffusion controlled redox behavior, which were characterized by the SEM, EDS, FT-IR, and AC impedance methods. Upon applying +1.4 V voltage, the sandwich-type electrochromic device (ECD) with ca. 290 nm thickness of the EP film exhibits a distinct color transformation from red (CIE coordinates: L = 50.75, a = 18.58, b = 5.69) to dark blue (CIE coordinates: L = 45.65, a = −1.35, b = −12.49). Good electrochromic (EC) parameters, such as a large optical contrast (ΔT%) of 78%, quick coloration and bleaching response times of 2.9 s and 1.1 s, high coloration and bleaching efficiencies of 278.0 and 390.5 C−1·cm2, and good cycling stability (maintains 70% of the initial ΔT% value after 3200 voltage switching cycles), were obtained. [ABSTRACT FROM AUTHOR]

Spent Bleaching Earth (SBE) is solid waste categorized as hazardous waste with code number B413 based on the Republic of Indonesian Government regulation number 101/2014 and number 22/2021. Improper processing of SBE can be triggering spontaneous ignition and pose environmental pollution due to the high of oil content which is about 20-30 %. SBE has the potential to be reused as an adsorbent in the crude oil bleaching process. In this research, the reactivation process was carried out using acid activation and followed by calcination. SBE was successfully reactivated using sulphuric acid (H2SO4) and hydrochloric acid (HCl) with various concentrations (5-20%), then, followed by a calcination process at 600-700°C for 90 and 120 min. The results showed that the physical appearance color of the bleaching earth (BE) after reactivation and calcination at temperatures above 600 °C resembled color of virgin bleaching earth (light brown). The characterization of reactivated spent bleaching earth (RSBE) product using X-Ray Fluorescence showed that the highest percentage value of silica content is 68.28 % and 74.42 %, under the reactivation condition using 15 % H2SO4 (calcination temperature and time at 600 °C and 120 min) and 20 % HCl (calcination temperature at 600 °C, and 90 min), respectively. The characterization results using Brunauer Emmett Teller (BET) analyzer, showed that the surface area of RSBE using HCl 20 % is about 150 m2/g. However, the surface area RSBE with activator H2SO4 15 % (146 m2/g). These results showed that the RSBE with HCl activator has a larger surface area than activator H2SO4, and has good absorption ability. As evidenced by the percentage of bleaching power that the RSBE with activator HCl has 72.92 % higher than RSEBE with activator H2SO4 15 % of 70.73 %. The best adsorption capacities of adsorbent were then tested for its performance to purify crude palm oil (CPO). The result shows that the RSBE met the Indonesian Industry standard (SNI 13-6336-2000) for the bleaching of CPO processes. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effects of coffee staining and bleaching applications on the optical properties of CAD-CAM blocks, and to provide a three-dimensional visualization of surface changes with atomic force microscope (AFM). Methods: 80 samples were prepared from four different CAD-CAM blocks: [Cerec (CR), Shofu (SH), Cerasmart (CRS), Lava Ultimate (LU)], and a microhybrid composite resin [Filtek Z250 (Z250)]. After staining, the samples were divided into two subgroups according to bleaching methods: 16% carbamide peroxide (HB), and 40% hydrogen peroxide (OB). Color measurements were performed at baseline (t0), after staining (t1), and after bleaching (t2) to obtain translucency parameters (TP00), color change (Î"E00), and whiteness index (WID) values. Surface roughness analysis (Ra) was performed with AFM after coffee staining and bleaching procedures (at t1 and t2). Data were analyzed with Generalized Linear Model, and Bonferroni correction (P< 0.05). Results: TP00 values increased only in the CRS group after the bleaching application, and the effect of method was again observed only in CRS. While bleaching increased WID values of all groups except CRS, no difference was found between bleaching methods. Regardless of evaluation time, the roughest group is Z250, and the only difference between bleaching methods was observed in the CR group. In conclusion, the effects of staining and bleaching applications on the optical and surface properties of CAD-CAM blocks are material-dependent. [ABSTRACT FROM AUTHOR]

Background and objectives: Pulp bleaching is a concern of many conservationists. Research has been conducted with the aim of evaluating some traditional bleaching materials used in the preservation of documents and books, such as hydrogen peroxide and sodium borohydride, which shows that these materials do not significantly improve the mechanical properties of historical papers. Also, investigating the effect of reducing agents on oxidized papers has shown the effectiveness of tert-butylamine borane complex. In another study, five dyeing processes with oxidizers (calcium hypochlorite, hydrogen peroxide in two concentrations, light bleaching and potassium permanganate) and two dyeing processes with reducing agents (sodium borohydride and tert-butylamine borane) were compared. Their effect on alfa cellulose (Whatman filter paper) and two different historical papers have been investigated. The results indicate that all the tested dye removal methods have led to a clear increase. Due to the differences of opinion, in this research, the effectiveness of two reducing agent sodium borohydride and sodium dithionite on the appearance and structural characteristics of paper is investigated. Methodology: In this research, Whatman Filter Paper No. 1 (Whatman Filter Paper No. 1) made in England with a thickness of 180 microns, diameter of 11 cm, basis weight of 87 grams per square meter and ash content of 0.06% was used. . Chemical reagents including potassium persulfate, sodium borohydride and sodium dithionite reagent grade were prepared in a laboratory from Merck, Germany.Three solutions including potassium persulfate (2% by weight/volume), sodium borohydride (1% by weight/volume), sodium dithionite (1% by weight/volume) in distilled water (distilled water, pH; 7), to perform tests on zinc. Paper samples have been used by immersion. Whatman filter paper samples were subjected to oxidation in 2% peta persulfate in distilled water for 2 days (48 hours) and then the samples were immersed. Next, the identified samples were modified by two solutions of sodium borohydride and sodium dithionite 1% in distilled water for 1 to 5 hours and then purified in distilled water. Also, the samples were subjected to accelerated aging according to ASTM standard number D4714-96 at a temperature of 90±2 centigrade and a relative humidity of 50±2% for 384 hours. Test methods include potentiostat, colorimetry, tensile strength, pH measurement, scanning electron microscope and infrared examination. Results: The results show that potassium persulfate is the most neutralizing solution among the three solutions used on the first day, and it also indicates the reducing power of two solutions of sodium dithionite and sodium borohydride, which according to the test results, sodium borohydride is the reducing power compared to sodium dithionite. The sample prepared with pH 3.92, after accelerated aging, was accompanied by an increase of several units of pH after modification with two reducing substances. Examining the data obtained from the tensile strength test shows that in comparison with the tested samples with a tensile index of 1.06, the samples modified with sodium borohydride and sodium dithionite increased the index in all five modified periods. The infrared spectrometry investigation of the samples modified with sodium borohydride and sodium dithione shows that this old material improves the structure of cellulose after aging by changing the C=O bonds to C-O and reducing the area of 1640 cm-1.. The reduction of the absorption band in the region of 1640 cm-1 has been opened in almost all time cases with this material compared to the modified sample. Based on the data, samples modified with sodium borohydride and sodium dithionite had a significant increase (approximately 25 units) in the Lfactor (light-darkness) after aging, indicating that two substances have increased the brightness of the sample by reviving the color compounds. In the microscopic examination of the surface of the fibers, in the samples identified with potassium persulfate, local separation of the fibers is observed. In the samples modified with sodium borohydride and sodium dithionite, fibers with higher consistency and entanglement are observed. Conclusion: Double bonds and carbon groups in paper samples formed with potassium persulfate have been the main responsible for the yellowness and darkness of the paper. The reducing agents, sodium borohydride and sodium dithionite reduce this aldehyde and ketone to hydrocarbon. With the loss of multiple conjugates, the light absorption of the paper is reduced and this causes the paper to brighten. The double bonds and their regeneration also cause rearrangement of the cellulose chain, which has resulted in increasing the mechanical resistance and strength of the paper samples. [ABSTRACT FROM AUTHOR]

Azoheteroarenes are emerging as powerful alternatives to azobenzene molecular photoswitches. In this study, water‐soluble arylazoisoxazole photoswitches are introduced. UV/vis and NMR spectroscopy revealed moderate to very good photostationary states and reversible photoisomerization between the E‐ and Z‐isomers over multiple cycles with minimal photobleaching. Several arylazoisoxazoles form host–guest complexes with β‐ and γ‐cyclodextrin with significant differences in binding constants for each photoisomer as shown by isothermal titration calorimetry and NMR experiments, indicating their potential for photoresponsive host–guest chemistry in water. One carboxylic acid functionalized arylazoisoxazole can act as a hydrogelator, allowing gel properties to be manipulated reversibly with light. The hydrogel was characterized by rheological experiments, atom force microscopy and transmission electron microscopy. These results demonstrate that arylazoisoxazoles can find applications as molecular photoswitches in aqueous media. [ABSTRACT FROM AUTHOR]

Alkylation of one of the inner‐core nitrogen atoms is one possible approach to obtain dianionic corrole ligands, suitable for the coordination of divalent metal ions, such as PdII. Inner‐core N‐methylation can be obtained by treating the corrole with CH3I, but the reaction conditions should be optimized to limit the formation of the dimethylated derivative. Two regioisomers, the N‐21 and the N‐22 methyl derivatives are obtained from the reaction, with the first product achieved in a higher amount. Structural characterization of the reaction products evidenced the distortion induced by the introduction of the methyl groups; the N‐methylcorroles are chiral compounds, and the enantiomers were separated by chromatography, with their absolute configuration assigned by ECD computation. Palladium insertion was achieved in the case of monosubstituted corroles, but not with the dimethylated macrocycle; X‐ray characterization of the complexes showed the distortion of the macrocycles. The Pd complexes do not show luminescence emission, but are able to produce singlet oxygen upon irradiation. The PdII complexes were also inserted in human serum albumin (HSA) and dispersed in water; in this case, the protein protects the corroles from photobleaching, and a switch from the type II to the type I mechanism in reactive oxygen species (ROS) production is observed. [ABSTRACT FROM AUTHOR]

Cellulose microfibrils were isolated from coffee parchment through acid hydrolysis, alkaline hydrolysis, and bleaching. Factorial design experiments allowed studying the influence of the chemical precursor concentrations and reaction times on the mass losses. TGA, SEM, XRD, and FT-IR techniques allowed for characterizing the coffee parchment hydrolyzed and bleached. Obtained results suggest that acid hydrolysis breaks down the lignocellulosic compounds from the coffee parchment, and alkaline hydrolysis allows the solubilization of lignin and hemicellulose. Lignocellulosic compound dissolution produces a reduction/disappearance of some vibrational bands. This dissolution enhances the crystalline index and decreases the microfibril's diameter. However, in coffee parchment, the microfibrils are twisted, giving the appearance of fibers with a minor diameter. The design of the experiment results suggests that the main factors during acid and alkaline hydrolysis are the concentration of the chemical precursors. In the bleaching process, a variation in the factors does not significantly influence the response variable. However, for brightness, the precursor concentration affects the cellulose quality. The optimal conditions for cellulose extraction from coffee parchment are 5% (v/v) of HNO3 by 2 h, 3% (m/v) NaOH by 60 min, and a 1:1 mass of NaClO:CH3COOH by 45 min for bleaching. [ABSTRACT FROM AUTHOR]

Novel hierarchical metal-organic framework/chitosan aerogel composites were developed for oil bleaching. UiO-66-COOH-type metal organic frameworks (Zr-MOFs) were synthesized and integrated onto a chitosan matrix with different contents and named MOF-aerogel-1 and MOF-aerogel-2. Due to the compatibility of chitosan, the carboxylic zirconium MOF-aerogels not only maintained the inherent chemical accessibility of UiO-66-COOH, but the unique crystallization and structural characteristics of these MOF nanoparticles were also preserved. Through 3-dimensional reconstructed images, aggregation of the UiO-66-COOH particles was observed in MOF-aerogel-1, while the MOF was homogeneously distributed on the surface of the chitosan lamellae in MOF-aerogel-2. All aerogels, with or without immobilized MOF nanoparticles, were capable of removing carotenoids during oil bleaching. MOF-aerogel-2 showed the most satisfying removal proportions of 26.6%, 36.5%, and 47.2% at 50 °C, 75 °C, and 100 °C, respectively, and its performance was very similar to that of commercial activated clay. The reuse performance of MOF-aerogel-2 was tested, and the results showed its exceptional sustainability for carotenoid removal. These findings suggested the effectiveness of the MOFaerogel for potential utilization in oil bleaching treatments. [ABSTRACT FROM AUTHOR]

Introduction. Dental bleaching is the first choice to improve smile esthetics, but, in some cases, it needs to be associated with resin composite restoration to obtain a satisfactory result. Unfortunately, the bonding of resin-based materials can be impaired due to residual oxygen molecules, which can decrease the durability of the restoration. Objectives. To evaluate the effect of the antioxidant application on the bond strength of bleached enamel after 24 hr and 3 years of water storage. Methods. In total, 84 bovine teeth were used in this study. Of these, 77 were bleached with 35% hydrogen peroxide in a single session for three cycles of 15 min. Then, the specimens were divided into groups (n = 7 each): control (without bleaching), without antioxidant (WA) use; application of 10% sodium ascorbate (SA) gel, grape seed (GS) extract, and aloe vera (AV). The restorative procedure was performed immediately after bleaching, 7 and 14 days after bleaching. Specimens were sectioned and evaluated using microtensile bond strength (μTBS). Half of the resin-enamel sticks were tested after 24 hr, and the remaining half after 3 years of water storage. µTBS data were analyzed using a three-way analysis of variance, Tukey's test, and Dunnett's test. Results. The lowest µTBS values were observed when the restoration was performed immediately after bleaching in the AV, GS, and WA groups when compared with the SA group (p < 0.005). However, no significant differences were observed among all groups after 3 years of water storage (p < 0.001). Conclusions. SA at 10% was the most effective antioxidant agent for improving the immediate bond strength. However, independent of the antioxidant agent used, the bond strength values were maintained or recovered after 3 years of water storage. SA at 10% could be used to avoid delayed bonding procedures after in-office whitening without compromising bond strength over time. Clinical Significance. The use of antioxidants after dental bleaching can be effective in improving the bonding durability of the adhesive restorations. [ABSTRACT FROM AUTHOR]

Natural antioxidants have become vital to minimize macromolecular damage caused by Reactive Oxygen Species (ROS). This study investigated the antioxidant property of β-cryptoxanthin (β-CRX) extracted from Kocuria marina DAGII and its protective effect against macromolecular damages by generating ROS via two models: UV radiation and the Fenton reaction. β-cryptoxanthin exhibited the highest scavenging activity towards hydrogen peroxide radicals with an IC50 value of 38.30 ± 1.13 μg/ml, favoring the hydrogen atom transfer mechanism. The total antioxidant capacity value of 872.0101 ± 1.84 μg BHT/mg β-CRX indicated the cumulative ROS scavenging ability of β-cryptoxanthin. β-cryptoxanthin could protect against ROS-induced lipid peroxidation, protein oxidation, and DNA damage. The highest lipid peroxidation and protein oxidation inhibition values of β-cryptoxanthin against ROS were 99.371 ± 0.51% and 78.19 ± 0.15%, respectively. β-cryptoxanthin also showed a protective effect in maintaining DNA intactness against ROS-mediated DNA damage. Allium cepa test showed the non-genotoxic nature of β-cryptoxanthin and its protective effect against ROS genotoxic effects. A photo-stability study of β-cryptoxanthin toward UVA and UVB radiation showed a rapid bleaching result of UVB obeying pseudo-zero order kinetics with an average R2 value of 0.9897 and a higher k value (−6.3 × 10–11 ± 0.2 M/s) than UVA (k value −3.1 × 10–11 ± 0.17 M/s), signifying that UVB is more potent toward photo-degradation. The good SPF value of 23.1737 ± 0.15 showed the UV protection capability of β-cryptoxanthin. Thus, the present study suggests that β-cryptoxanthin could be a valuable antioxidant to protect against ROS-induced various macromolecular damages and act as a good UV protectant. [ABSTRACT FROM AUTHOR]

It is important to precisely polish the inner surface of medical-grade TA1 pure titanium capillary tubes in order to reduce sample residue and enhance capillary pipetting precision, ultimately improving the accuracy and reliability of in vitro diagnostic equipment. To address the subpar inner surface quality of TA1 capillary tubes and the challenges associated with titanium material polishing, a novel chemically-assisted magnetic compound fluid polishing method was proposed. This method combines oxidation and mechanical removal to efficiently and precisely polish the inner surface of the tubes. Experimental studies were carried out to examine the effects of iron powder mass, hydrogen peroxide concentration and malic acid concentration on both the material removal rate and the inner surface roughness, with the aim of determining the optimal polishing parameters. The study involved the examination of surface morphology and elemental changes on the inner surface of capillary tubes both before and after polishing. This analysis aimed to assess the overall impact of the polishing technique on the inner surface of pure titanium capillary tubes. The results indicated that following a 90-minute polishing process under the specified conditions of 2 mg of iron powder, a hydrogen peroxide concentration of 7.2% and a malic acid concentration of 6%, the surface roughness of the TA1 capillary tube decreased from Ra 675 nm to Ra 75 nm. In the well-polished area devoid of initial dents, the surface roughness reached Ra 19.5 nm, with a material removal depth of up to 28 µm. Furthermore, the original surface scratches were effectively eliminated, both the depth and width of dents were significantly reduced, and no additional elements were introduced during the polishing process. [ABSTRACT FROM AUTHOR]

The CLC-ec1 chloride/proton antiporter is a membrane-embedded homodimer with subunits that can dissociate and associate, but the thermodynamic driving forces favor the assembled dimer at biological densities. Yet, the physical reasons for this stability are confounding as dimerization occurs via the burial of hydrophobic interfaces away from the lipid solvent. For binding of nonpolar surfaces in aqueous solution, the driving force is often attributed to the hydrophobic effect, but this should not apply in the membrane since there is very little water. To investigate this further, we quantified the thermodynamic changes associated with CLC dimerization in membranes by carrying out a van ‘t Hoff analysis of the temperature dependency of the free energy of dimerization, ΔG°. To ensure that the reaction reached equilibrium at different temperatures, we utilized a Förster resonance energy transfer assay to report on relaxation kinetics of subunit exchange as a function of temperature. Equilibration times were then applied to measure CLC-ec1 dimerization isotherms at different temperatures using the single-molecule subunit-capture photobleaching analysis approach. The results demonstrate that the dimerization free energy of CLC in Escherichia coli–like membranes exhibits a nonlinear temperature dependency corresponding to a large, negative change in heat capacity, a signature of solvent ordering effects such as the hydrophobic effect. Consolidating this with our previous molecular analyses suggests that the nonbilayer defect required to solvate the monomeric state is one source of the observed change in heat capacity and indicates the existence of a generalizable driving force for protein association in membranes. [ABSTRACT FROM AUTHOR]

Objective The aim of this in vitro study was to evaluate the color changes produced by different bleaching techniques on two different stained ceramic materials. Material and methods The total 40 specimens of IPS e.max and shofu were stained by immersing in coffee 30 min daily for 14 days and color assessment was done by spectrophotometer, then the specimens were divided into two subgroups according to the bleaching technique home bleaching (white smile) and office bleaching (pola office), the bleaching was done according to manufacturer instruction for pola office: an adequate thickness of the bleaching agent by the brush was applied for 8 min. This procedure was repeated for 3 times. And for home bleaching (white smile): specimens were placed in the mold to receive home bleaching agent by immersion 60 min daily for 6 days. Then the color was assessed after bleaching procedure to determine the changes. The data were statistically analyzed by one-way ANOVA test and Correlation analysis. Results Shofu recorded higher staining affinity with mean value 6.72 ± 2.33 than (IPS) e.max group with mean value 4.92 ± 2.08. For bleaching: Shofu HC group home bleaching group recorded higher bleaching affinity with mean value 7.86 ± 1.93 whereas shofu office bleaching group recorded mean value 6.04 ± 0.65. As for e.max home bleaching group recorded also higher △ E with mean value 5.68 ± 0.86 whereas e.max office bleaching group recorded mean value 4.37 ± 1.01. And a strong relation was recorded between △E1 and △E2 in all groups as r greater than 0.5. Conclusion Shofu HC and IPS e.max showed affinity to staining but Shofu HC showed higher stain ability than IPS e.max, Office and home bleaching techniques affected the color of both ceramics materials and home bleaching showed higher significant difference. And Shofu HC showed higher color change after home and office bleaching than IPS e.max. [ABSTRACT FROM AUTHOR]

Biomass-derived carbon dots (C-dots) are considered a very important carbon material in metal ion detection of their small environmental impact, simple preparation process, and relatively low cost. A green approach for synthesizing biomass-derived C-dots from Chenpi using a hydrothermal method without further processing is proposed in the present study. The as-synthesized C-dots show excellent fluorescence properties, superior resistance to UV irradiation photobleaching, and high photostability in salt-containing solutions. The C-dots were used in the form of label-free fluorescent probes for sensitively detecting Hg2+ selectively. The outcome relationship behaved linearly and was established based on a given range between 10-300 nM concentration, with a detection limit of 7.0 nM. This green strategy obtains a high C-dot quantum yield of 10.8% and satisfactory results in detecting Hg2+ in actual water samples. [ABSTRACT FROM AUTHOR]

The stable nitrogen isotope composition of bivalve shell organics serves as a proxy for nitrogen fluxes in modern and past ecosystems. An essential prerequisite to reconstruct environmental variables from δ15N values of bivalve shells is to understand if pristine isotope signals can be retrieved from shell organics after sample pretreatment. δ15N analyses of fossil shells should be limited to the intra‐crystalline organic matrix (intra‐OM), which is trapped within biomineral units and less likely contaminated or diagenetically overprinted than inter‐crystalline organics (inter‐OM). However, it remains unclear whether the different shell organic phases (insoluble/soluble inter‐OM, intra‐OM) are isotopically distinct and whether δ15N values of intra‐OM agree with those of bulk organic matter. These questions were tackled by applying different solvents (H2O, HCl, H2O2, NaOCl) to homogenized shell powder of a modern Arctica islandica. Milli‐Q water did not alter bulk δ15N values indicating the dissolution of the inter‐OM was negligible. Acid‐extracted intra‐OM exhibited a larger isotope variation within replicates and showed a minor but significant fractionation in bulk δ15N values related to the loss of acid‐soluble components. Compared to H2O2, NaOCl oxidative treatment was more effective in cleaning inter‐OM and produced reliable bulk and amino acid (AA)‐specific δ15N data of intra‐OM. Furthermore, differences in the relative abundance and δ15N values of individual AAs suggested that the N isotope composition is not uniform within shells, and the N‐bearing content and AA composition differ between organic phases. Future studies should test the capability of bulk and CSIA‐AA δ15N proxies in fossil shells as paleoenvironmental archives. Plain Language Summary: The nitrogen isotope ratio (15N/14N) of organics embedded in bivalve shells can be used to understand biogeochemical processes in the environment. When applying chemical solvents to clean the shells, some organic phases are inevitably lost. To evaluate the potential effects of chemical cleanings on nitrogen isotope composition (δ15N) in shell organics, we applied various solvents to modern shell samples. Most of the shell organic phases carry specific distinct amino acid (AA) compositions and therefore have different nitrogen isotope compositions. These results imply that the nitrogen‐bearing contents (such as AA) and their isotope compositions are not uniform within shells. Specifically, we compared the organics entrapped inside crystals (intra‐OM) with the total shell organics (raw‐OM). The offsets in bulk δ15N data between the two phases were mainly driven by the difference in AA proportions, while little differences were observed in δ15N values of AA. Technically, using raw shells without chemical pretreatment and using a bleaching protocol is suitable for raw‐OM and intra‐OM, respectively, to obtain the bulk and AA‐specific δ15N data. These findings indicate that raw‐OM is sufficient for bulk and AA‐specific δ15N analyses in modern bivalve shells for environmental reconstructions and provide a framework to study the fossil shells. Key Points: Organic phases in modern bivalve shells carry different nitrogen isotope compositionsThe amino acid composition differed between total organics and intra‐organics, resulting in different nitrogen isotope data [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate different delaying times after bleaching and the use of different sodium ascorbate (SA) concentrations (10% and 35%) in the bond strength of adhesive cementation to enamel. This study used 54 sound bovine incisors, which were randomly assigned to the following groups: G1 (unbleached/control+ adhesive cementation (AC)); G2 (bleached + AC after 7 days); G3 (bleached + 10% SA + AC after 24 h); G4 (bleached + 10% SA + AC after 7 days); G5 (bleached + 35% SA + AC after 24 h); and G6 (bleached + 35% SA + AC after 7 days). After bleaching, G3, G4, G5, and G6 received an application of SA before the cylinders build up with RelyX Veneer cement. The samples were subjected to microshear test, and the results were analyzed by two-way ANOVA with Tukey's post hoc test. Group one presented the highest mean bond strength (19.1 MPa) and G3 the lowest (16.96 MPa). There was no statistical difference between the groups tested (p ˃ 0.05). The fracture pattern observed was predominantly mixed. The adhesive cementation may be performed 24 h after bleaching when SA (10% or 35%) is used or after 7 days, without compromising bond strength. [ABSTRACT FROM AUTHOR]

Twenty novel Mn, Fe, and Cu complexes of ethylene cross-bridged tetraazamacrocycles with potentially copolymerizable allyl and benzyl pendant arms were synthesized and characterized. Multiple X-ray crystal structures demonstrate the cis-folded pseudo-octahedral geometry forced by the rigidifying ethylene cross-bridge and show that two cis coordination cites are available for interaction with substrate and oxidant. The Cu complexes were used to determine kinetic stability under harsh acidic and high-temperature conditions, which revealed that the cyclam-based ligands provide superior stabilization with half-lives of many minutes or even hours in 5 M HCl at 50–90 °C. Cyclic voltammetry studies of the Fe and Mn complexes reveal reversible redox processes indicating stabilization of Fe2+/Fe3+ and Mn2+/Mn3+/Mn4+ oxidation states, indicating the likelihood of catalytic oxidation for these complexes. Finally, dye-bleaching experiments with methylene blue, methyl orange, and rhodamine B demonstrate efficient catalytic decolorization and allow selection of the most successful monomeric catalysts for copolymerization to produce future heterogeneous water purification materials. [ABSTRACT FROM AUTHOR]

Using different bleaching materials to eliminate or reduce organic volatiles in deteriorated olive oils will positively affect its characteristics. This study aims to identify the volatiles of oxidized olive oil after physical bleaching using selected immobilized adsorbents. Oxidized olive oil was eluted using open-column chromatography packed with silica gel, bentonite, resin, Arabic gum, and charcoal at a 1:5 eluent system (w/v, adsorbent: oxidized olive oil). The smoke point was determined. The collected distilled vapor was injected into GC-MS to identify the volatiles eluted after partial refining with each of these bleaching compounds. The results showed that volatile compounds were quantitatively and qualitatively affected by the type of adsorbents used for the elution of olive oil and the smoking points of eluted oils. The most prominent detected volatile compounds were limonene (14.53%), piperitone (10.35%), isopropyl-5-methyl-(2E)-hexenal (8.6%), methyl octadecenoate (6.57%), and citronellyl acetate (5.87%). Both bentonite and resin were superior in decreasing the ratio of volatile compounds compared with other bleaching materials used. Resin immobilized medium was significantly affected (p < 0.05), raising the smoke point. These results highlighted some information regarding the characteristics of volatile compounds that result after the physical elution of olive oil through selected adsorbents. [ABSTRACT FROM AUTHOR]

Nitrogen-vacancy (NV) and other color centers in diamond have attracted much attention as non-photobleaching quantum emitters and quantum sensors. Since microfabrication in bulk diamonds is technically difficult, embedding nanodiamonds with color centers into designed structures is a way to integrate these quantum emitters into photonic devices. In this study, we demonstrate a method to incorporate fluorescent nanodiamonds into engineered microstructures using two-photon polymerization (2PP). We studied the optimal concentration of nanodiamonds in the photoresist to achieve structures with at least one fluorescent NV center and good structural and optical quality. Fluorescence and Raman spectroscopy measurements were used to confirm the presence and location of the nanodiamonds, while absorbance measurements assessed scattering losses at higher concentrations. Our results show the feasibility of fabricating microstructures embedded within fluorescent nanodiamonds via 2PP for photonics and quantum technology applications. [ABSTRACT FROM AUTHOR]

The aim of this in vitro study is to evaluate the bleaching efficiency of 5 different office bleaching methods and the changes in enamel morphology after bleaching. In this study, 75 human molar teeth are used. The teeth are divided in half in the mesiodistal direction, and a total of 150 enamel samples are obtained. The obtained samples are split into 3 main groups to evaluate the bleaching efficiency, surface roughness, and enamel surface hardness, and each group is composed of 50 samples. Then, each main group was divided into 5 separate subgroups (n = 10) containing 5 varied bleaching techniques. Before the bleaching, color measurement with a spectrophotometer, surface roughness with a profilometer, and microhardness measurement with Vickers test device are performed. After that, different bleaching procedures are applied to the 5 subgroups formed. As a result of the statistical evaluation, it is found that there is a significant level of bleaching in all groups (p < 0.05). In the comparison between the groups, there is no remarkable divergence in terms of hardness and roughness levels (p˃0.05). In light of the findings obtained from our study, we suggest that ozone can be used as an alternative bleaching agent to hydrogen peroxide. In addition, it is discovered that the use of light activation is not necessary to increase bleaching effectiveness. Finally, we believe that enamel surface morphology may be affected after office bleaching methods; therefore, various precautions should be taken before and after bleaching. [ABSTRACT FROM AUTHOR]