KNO3 Research Articles

Enhancing drought, heat shock, and combined stress tolerance inMyrobalan29C rootstocks with foliar application of potassium nitrate.

Drought and heat stress are significant concerns to food security in arid and semi-arid regions, where global warming is predicted to increase both frequency and severity. To cope with these challenges, the use of drought-tolerant plants or technological interventions are essential. In this study, the effects of foliar potassium nitrate (KNO3) application on the stress tolerance and recovery of Myrobalan 29C rootstocks (Prunus cerasifera Ehrh.) were evaluated. These rootstocks are widely recognized for their adaptability and are extensively used in fruit production. To assess their response, the rootstocks were subjected to drought, heat shock, or a combination of both stressors. Additionally, they were treated with 1.0% KNO3 via foliar application. Throughout the stress and recovery periods, various morphological, physiological, and bio-chemical parameters were measured. Based on our results, KNO3 treatment improved LRWC, Chl stability, SC, and key stress markers like proline, MDA, H2O2, along with antioxidant enzymes CAT, SOD, POD during both stress and recovery phases. Moreover, our results emphasized KNO3's critical role in hormone regulation under stress. KNO3 application significantly altered hormone levels, notably increasing ABA during drought and heat shock stress, essential for stress response and adaptation. In contrast, IAA, GA, and cytokinin's significantly increased during the recovery phase in KNO3-treated plants, indicating improved growth regulation and stress recovery. In addition, KNO3 application improved the recovery process of the rootstocks by restoring their physiological and biochemical functions. This study suggests that the application of foliar KNO3 is an effective technique for enhancing the drought and heat tolerance as well as the recovery of Myrobalan 29C rootstocks. These results hold significant value for farmers, policymakers, and researchers, as they offer crucial insights into the development of drought-tolerant crops and the management of climate change's adverse effects on agriculture.

Enhancing bending performance of ultrathin flexible glass through chemical strengthening

AbstractFlexible glass with high bending strength is a remarkable component of flexible electronic displays. However, as a brittle material, its bending properties often do not meet requirements of application. To address this challenge, the application of chemical strengthening stands out as a viable approach to significantly bolster scratch resistance and bending strength in flexible glass. This study focuses on a conventional one‐step chemical strengthening method, employing molten potassium nitrate, to reinforce ultrathin aluminosilicate glass produced through the secondary down‐drawing thermoforming process. Effects of ion‐exchange temperature and time on mechanical properties of strengthened 110 µm flexible glass were investigated, and moreover, properties of strengthened ultrathin flexible glass with various thicknesses were compared. The results indicate that, after chemical strengthening at 380°C for 1 h, the compressive stress (CS) of 110 µm glass reaches 864.60 MPa, and the depth of layer is 15.86 µm, at which time the glass has the best bending performance and scratch resistance, and half of the faceplate spacing during glass breakage can be enhanced from 38.02 ± 2.7 to 8.40 ± 0.62 mm. For ultrathin flexible glass from 40 to 110 µm, after treatment at 380°C for 1 h, the CS of thick glass is higher than that of thin glass, and the enhancement of bending performance is better.

Assessment and selection of flowering inducers to increase productivity of mango cv. Ataulfo (Mangifera indica L.)

Objective: To assess new flowering inducers used to increase the fruit yield in mango cv. Ataulfo trees, to substitute paclobutrazol. Design/methodology/approach: Ten-year-old mango cv. Ataulfo trees were used, homogeneous in terms of health. The treatments evaluated were prohexadione calcium, cytokinins, itaconic acid, phosphonitrate, potassium nitrate and paclobutrazol. The experimental design was completely random blocks with five repetitions; each experimental unit and repetition consisted of one tree. The number of inflorescences, percentage of flowering, number of fruits, fruit yield by hectare, and profitability of treatments were assessed. The data were analyzed through ANOVA and Tukey’s means comparison (p<0.05). Results: There were no significant effects of the treatments for number of inflorescences, percentage of flowering, and number of fruits; however, the homogeneous formation of inflorescences was found with itaconic acid. Prohexadione calcium (P-Ca) presented the highest fruit yield (19.32 t ha-1), but it does not differ from paclobutrazol (10.34 t ha-1). The highest profitability of the crop was obtained with prohexadione calcium, in which for each peso invested the amount of $1.51 was recovered. Findings/conclusions: Prohexadione calcium can be an alternative for the use of paclobutrazol to induce flowering and increase the fruit yield of mango cv. Ataulfo in the Coast of Guerrero.

Optimization of an Alternative Culture Medium for Phycocyanin Production from Arthrospira platensis under Laboratory Conditions.

Arthrospira platensis, known as spirulina, is a cyanobacterium with multiple nutritional benefits, as it contains substantial amounts of proteins, fatty acids, and pigments. However, the production of this microalga has faced significant challenges, primarily related to the cost and composition of the required culture medium for its optimal growth. This study focused on optimizing two nitrogen sources (urea and potassium nitrate) to maximize the growth of A. platensis and the production of phycocyanin, a photosynthetic pigment of significant commercial value. Optimization was performed using the response surface methodology (RSM) with a central composite design (CCD). Analysis of variance (ANOVA) was employed to validate the model, which revealed that the different concentrations of urea were statistically significant (p < 0.05) for biomass and phycocyanin production. However, potassium nitrate (KNO3) showed no significant influence (p > 0.05) on the response variables. The RSM analysis indicated that the optimal concentrations of KNO3 and urea to maximize the response variables were 3.5 g L-1 and 0.098 g L-1, respectively. This study offers valuable perspectives for the efficient production of A. platensis while reducing production costs for its cultivation on a larger scale.

Crosstalk of sucrose, potassium, and magnesium on growth, yield, and carbohydrate partitioning in bell pepper (Capsicum annuum L.) under poor light conditions

Bell pepper has received high demand due to its high nutritional value and contained antioxidant compounds. This research aimed to evaluate the effects of sucrose and some minerals on morpho-physiological characteristics, yield parameters, and carbohydrate partitioning in the bell pepper. The pot experiment was outlined hydroponically in a factorial format based on a completely randomized design. The first factor, sucrose, was sprayed in two concentrations (0 and 0.5% w/v) and the second factor, mineral nutrition, consisted of four levels (control, magnesium nitrate 0.5% w/v, potassium nitrate 0.5% w/v, magnesium nitrate 0.25% w/v + potassium nitrate 0.25% w/v). Results indicated that sucrose 5 + combined magnesium & potassium nitrate was superior in all of the biomass and yield parameters. In this combined treatment, fruit yield per plant and fruit vitamin C increased up to 44.03% and 47.71% in comparison with control. The highest leaf-soluble carbohydrate was recorded in plants treated with sucrose 5 + combined magnesium & potassium nitrate which was not significantly different from other contained sucrose treatments. The highest fruit soluble carbohydrate was observed in sucrose 5 + combined magnesium & potassium nitrate treatment as well, but its difference was not significant from sucrose 5 + potassium nitrate. The highest leaf potassium concentration was seen in three treatments that combined sucrose and minerals. The treatment of combined magnesium & potassium nitrate contributed to more leaf magnesium concentration compared with other nutrient treatments. In total, sucrose spray alongside combined magnesium & potassium nitrate led to higher carbohydrate accumulation in fruit, causing yield increment and nutritional value enhancement in bell peppers.

Production and characterization of protease enzyme from Acinetobacter pittii using peanut meal as substrate

ABSTRACT A significantly high protease enzyme yield of 617 U/ml was achieved with Acinetobacter pittii as the microorganism and peanut oil meal as the substrate. Peanut oil meal, which consists of proteins (40-60%) and carbohydrates (22-30%), serves as a sufficient source of nitrogen and carbon necessary for microbial growth and production of enzymes. Moreover, peanut meal offers the advantages of being affordable and available in large quantities, making the meal suitable for cost-effective enzyme production. In the present study, two bacterial strains and one fungal strain were selected to produce proteases utilizing peanut oil meal as the substrate. The experimental conditions during the enzyme production, including pH and temperature, were optimized. In addition, the substrate was enriched with various carbon and nitrogen sources. The microbial strains were streaked on nutritional agar (for bacteria) and potato dextrose agar (for fungus). Following an incubation period, the plates were stored at 4°C for further studies. The molecular weight of partially purified proteases of Acinetobacter pittii was found to be ≅ 95.5 kDa. Potassium nitrate was the most ideal nitrogen source (up to 411% increase in activity) and fructose was the best carbon source (425% increase). These enzymes exhibited excellent temperature tolerance and were capable of functioning over a wide pH range. Furthermore, the obtained proteases demonstrated ability to coagulate milk effectively, indicating their potential for various food-related applications.

Enabling High‐Performance Potassium‐Ion Batteries by Manipulating Interfacial Chemistry

AbstractAs a promising candidate for the flame‐retardant electrolyte, triethyl phosphate (TEP)/potassium bis(fluorosulfonyl)amide (KFSI)‐based electrolyte has drawn much attention in the K‐ion battery community. Although the TEP/KFSI formula at a moderate main salt concentration (normally, &lt;3 m) enables the compatibility of the reactive K metal anode, the long‐standing oxidative instability of KFSI salt remains unsolved. Here, an additive strategy is reported to address the high‐voltage issue in the TEP/KFSI electrolyte, and generalize it to the other KFSI‐based electrolytes. The addition of potassium nitrate changes the surface charge distribution and effectively suppresses the decomposition of KFSI toward the high‐voltage cathode. The nitrate‐containing electrolyte enables superior stability of a 4.3 V‐class K‐ion battery, as evidenced by its 80% capacity retention over 2000 cycles (≈6 months) at the 1 C rate. Moreover, the long‐cycling stability of the graphite‐based full cell with Prussian Blue cathode is demonstrated.

Investigation of physicochemical and chemical properties of biochar activated with carbonate, nitrate, and borohydride

AbstractActivation of biomass before pyrolysis with various chemicals significantly affects the surface area and porosity, chemical composition, and formation and distribution of functional groups on the surface of the biochar produced. For this purpose, raw tea waste (RTW) was mixed with potassium nitrate (KNO3), potassium sodium carbonate (NaKCO3), and sodium borohydride (NaBH4) in solid form and pyrolyzed at 500 °C for 1 h. The effects of the chemical activators on biomass char formation were investigated using DTA-TGA and DSC. Compared to conventional pyrolysis, carbonate, nitrate, and hydrides increase the gasification of biochar by catalyzing the decomposition of cellulose and lignin. The effect of NaBH4 on graphitization and deoxidation of carbon is higher than that of carbonates and nitrides. In addition, all prepared biochar samples were characterized by XRD, SEM, FT-IR, elemental analysis, and N2 adsorption–desorption. While treatment of RTW with KNO3 and NaKCO3 increased the hydroxylation of the biochar, treatment with NaBH4 decreased hydroxylation by increasing dehydrogenation and dehydroxylation. Increasing boron content led to hydroxylation of the material with hydratation of NaBO2. The surface area and pore distribution results showed that nitrates and carbonates have insignificant effect on the surface area of biochar, while NaBH4 almost doubles the surface area and total pore volume of biochar by forming hydrogen.

Effects of different levels of gibberellic acid and potassium nitrate solutions on the emergence and seedling vigor of amaranth and Cleome gynandra

AbstractThe effects of gibberellic acid and potassium nitrate on seed emergence and seedling growth of amaranth and Cleome gynandra were investigated in the greenhouse at Marondera University of Agricultural Sciences and Technology. The study was laid out in a factorial layout within a completely randomized design replicated three times. Potassium nitrate (dry seeds, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, and 1%) and gibberellic acid (dry seeds, 100, 200, 300, 400, 500, 600, 700, 800, 900, and 1000 parts per million) were used, respectively. A total of 100 seeds of both crops were planted in each plastic pocket. Seed emergence percentage and vigor index of amaranth and C. gynandra were evaluated. The effects were more pronounced in seeds treated with gibberellic acid than in potassium nitrate. Seed emergence and vigor index of amaranth and C. gynandra seeds treated with gibberellic acid showed a significant difference at p &lt; 0.01, while potassium nitrate showed no significant difference at p &gt; 0.05. The maximum seed emergence percentage of amaranth and C. gynandra was 67.1% and 64.8%, which was obtained in 2022 and 2021, while the lowest was 35.5% and 37.5%, which was obtained in 2021. The highest vigor index I of amaranth and C. gynandrawas 590.3 and 586.2, which was observed in 2022 and 2021, while the lowest vigor index I was 45.2 and 170, which was obtained in 2021 and 2022. The results obtained indicated that the application of gibberellic acid on seeds of amaranth and C. gynandra can alleviate seed dormancy.

Nutrient recovery from wastewater for hydroponic systems: A comparative analysis of fertilizer demand, recovery products, and supply potential of WWTPs

Nutrient recovery from wastewater treatment plants (WWTPs) for hydroponic cultivation holds promise for closing the nutrient loop and meeting rising food demands. However, most studies focus on solid products for soil-based agriculture, thus raising questions about their suitability for hydroponics. In this study, we address these questions by performing the first in-depth assessment of the extent to which state-of-the-art nutrient recovery processes can generate useful products for hydroponic application. Our results indicate that less than 11.5% of the required nutrients for crops grown hydroponically can currently be recovered. Potassium nitrate (KNO3), calcium nitrate (Ca(NO3)2), and magnesium sulfate (MgSO4), constituting over 75% of the total nutrient demand for hydroponics, cannot be recovered in appropriate form due to their high solubility, hindering their separated recovery from wastewater. To overcome this challenge, we outline a novel nutrient recovery approach that emphasizes the generation of multi-nutrient concentrates specifically designed to meet the requirements of hydroponic cultivation. Based on a theoretical assessment of nutrient and contaminant flows in a typical municipal WWTP, utilizing a steady-state model, we estimated that this novel approach could potentially supply up to 56% of the nutrient requirements of hydroponic systems. Finally, we outline fundamental design requirements for nutrient recovery systems based on this new approach. Achieving these nutrient recovery potentials could be technically feasible through a combination of activated sludge processes for nitrification, membrane-based desalination processes, and selective removal of interfering NaCl. However, given the limited investigation into such treatment trains, further research is essential to explore viable system designs for effective nutrient recovery for hydroponics.

Hybrid pathways of denitrification drive N2O but not N2 emissions from an acid-sulphate sugarcane soil

AbstractAcid-sulphate sugarcane soils in the subtropics are known hot-spots for nitrous oxide (N2O) emissions, yet the reduction of reactive N2O to non-reactive dinitrogen (N2) via specific pathways remains a major uncertainty for nitrogen (N) cycling and loss from these soils. This study investigated the magnitude and the N2O:N2 partitioning of N2O and N2 losses from a subtropical acid-sulphate soil under sugarcane production using the 15N gas flux method, establishing the contribution of hybrid (co- and chemo-denitrification) and heterotrophic denitrification to N2O and N2 losses. Soils were fertilised with potassium nitrate, equivalent to 25 and 50 kg N ha−1, watered close to saturation then incubated over 30 days. An innovative, fully automated incubation system coupled to an isotope-ratio mass-spectrometer enabled real time analysis of 15N2O and 15N2 at sub-diel resolution. Peak losses of N2O and N2 reached 6.5 kg N ha−1 day−1, totalling &gt; 50 kg of N2O+N2-N ha−1. Emissions were dominated by N2, accounting for more than 57% of N2O+N2 losses, demonstrating that the reduction of N2O to N2 proceeded even under highly acidic conditions. Over 40% of N2O, but only 2% of N2 emissions, were produced via hybrid pathways. These findings demonstrate hybrid pathways are generally limited to N2O production, likely driven by high organic matter content and low soil pH, promoting both biotic, and abiotic nitrosation. Regardless of the underlying process, the magnitude of the N2O emissions demonstrates the environmental, but also the potential agronomic significance, of hybrid pathways of N2O formation for N loss from fertilised acid-sulphate soils.

Potassium and Sulfur Fertilizer Sources Influence Alfalfa Yield and Nutritive Value and Residual Soil Characteristics in an Arid, Moderately Low-Potassium Soil

Alfalfa (Medicago sativa L.) requires a large amount of potassium (K) for maintaining forage yield and stand persistence. Therefore, soil inherently low in K levels must be supplemented with K fertilizers. Although several commercial K fertilizers are available on the market, choosing an appropriate K-supplementing source for a particular soil can be crucial in boosting alfalfa yield and nutritive value. A two-year study was conducted in an arid southern New Mexico location near Tularosa to evaluate the efficacy of three K commercial fertilizer sources in improving alfalfa yield and nutritive value in a moderately low potassium (84 ppm) soil. Nine K treatments or combinations and a no-K control were tested in a randomized complete-block design with four replications. Overall, supplementation of 160 kg ha−1 of K2O in all treatments resulted in a significant increase in alfalfa seasonal forage yield and nutritive value compared to the control. Sulfate of potash combined with ammonium sulfate (AS) produced greater seasonal yield compared to other fertilizers (muriate of potash and potassium nitrate) or combinations with gypsum (p &lt; 0.05). This treatment combination also showed greater crude protein, neutral detergent fiber, tissue Fe and S, and soil residual sulfate-S and nitrate-N. A positive correlation between sulfur abundance and nitrogen availability in alfalfa production was evident in the study. Addition of AS to all three K fertilizers yielded better seasonal forage yield than K fertilizers alone or K fertilizers in combination with gypsum. Adding gypsum to the K-fertilizers appeared to have negative effect on the seasonal forage yield. Future research should evaluate various combinations of the levels of K and S to determine the most reasonable balance.

Single-session associative protocol for dentin hypersensitivity management: a 1-year randomized, blinded clinical study.

This study aimed to establish a single-session associative protocol for non-restorative management of dentin hypersensitivity (DH). Twenty-four individuals with DH and a minimum sensitivity level of 4 on the visual analog scale (VAS) were selected. The study was conducted in a split-mouth design, with each participant (n = 20) having at least 1 affected tooth in all quadrants. The management protocols consisted of control group: universal adhesive, Neural Desensitizing Protocol group: 5% potassium nitrate, Mixed Desensitizing Protocol (PAM) group: 5% sodium fluoride and 5% potassium nitrate, Remineralizing Desensitizing Protocol (PDR) group: surface-partially reacted glass technology photopolymerizable varnish. Evaluations were performed immediately after application, at 1 week, 1 month, 2 months, and 12 months using the VAS sensitivity test. The scores were subjected to statistical analysis using the Friedman test (p < 0.05), Durbin-Conover test (p < 0.05), and Wilcoxon test (p < 0.05). At the 12-month evaluation, all groups showed statistically significant differences compared to the initial assessment. For the evaluation after 12 months, there was a statistically significant difference between the PAM group, the control group, and the PDR group. It can be concluded that all groups were effective in controlling DH, but there were significant results in the control group and PDR group. The clinical relevance of this study is to demonstrate that the application of single-session desensitizing protocols can be effective in controlling DH for up to 12 months. Brazilian Clinical Trials Registry Identifier: RBR-4r63d7s.

Seed priming as a method of preservation and restoration of sunflower seeds

The study focused on determining the preservative and restorative effects of seed priming with gibberellic acid (GA3) and potassium nitrate (KNO3) on sunflower seeds against deterioration. The seeds were immersed in different concentrations (0, 250, 500, and 1000 mg L−1) of GA3 and KNO3 solutions before and after being subjected to accelerated aging (AA). Unprimed seeds (NT) were used as control. The results showed that AA led to a reduction in germination percentage, germination index, and seedling growth parameters. However, seed primed with GA3 had a higher germination percentage after AA than NT. All seed primings shortened mean germination time and improved germination index. Seedling growth was stimulated by seed priming, and seed priming after AA produced more vigorous seedlings than primed seed before AA because they were severely affected by AA. In addition, hydration sufficiently induced the germination and seedling growth of aged seeds. A significant difference was found between GA3 and KNO3, and seeds were effectively protected from aging by GA3, while hydration promoted germination of aged seeds. Consequently, the recovery effect of seed priming was more pronounced than the conservative effect, and sunflower seeds should be primed with 500-1000 mg L−1 GA3 before storage or, if this is not possible, hydration improves the vitality and subsequent growth of aged sunflower seeds.

Seed Priming with Potassium Nitrate Can Enhance Salt Stress Tolerance in Maize

Seed Priming with Potassium Nitrate Can Enhance Salt Stress Tolerance in Maize

Carbon Paste Electrode Modified with PMBP: A Sensitive Sensor for Electrochemical Detection of Acetaminophen

In this present work, a sensitive electrocatalytic modified electrode based on 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP)/multiwalled carbon nanotubes (MWCNT) modified carbon paste electrode (CPE) was successfully developed. Electrochemical impedance spectroscopy, square wave voltammetry, chronocoulometry and cyclic voltammetry were used in prompt to evaluate the PMBP/MWCNT/CPE electrochemical capacity in detecting acetaminophen (APAP) in 0.1 M PBS pH 6.4. Under optimized conditions, PMBP/MWCNT/CPE displayed a well-defined electrocatalytic activity towards APAP oxidation in the linear responses which range from 1 μM to 1 mM (R2 = 0.991) with the LOD obtained at 0.245 μM while LOQ 0.816 μM. The presence of excess (10-fold and 25-fold) interferents such as sucrose, fructose, glucose, sodium chloride, sodium sulphate, potassium nitrate, lysine, potassium chloride and magnesium chloride as interferents was insignificant. The results presented in this study provide new perspectives on PMBP as a potential nanomaterial in the development of APAP sensors. As a conclusion, the PMBP/MWCNT/CPE revealed good stability, reproducibility, and repeatability, and was discovered to be relevant for usage in the pharmaceutical samples with satisfactory performance.

The Impart and Effect of Silicon and Potassium Nitrate in Dealing with Environmental Stress on Wheat Resistance in Saline Soil

The Impart and Effect of Silicon and Potassium Nitrate in Dealing with Environmental Stress on Wheat Resistance in Saline Soil

Thermal Stability and Performance Evaluation of Hitec Molten Salt for High-Temperature Energy Storage Applications

The quest for advanced materials in thermal energy storage (TES) has become paramount in a world grappling with pressing demands for sustainable and reliable energy solutions. Among these materials, molten salts have emerged as up-and-coming contenders, owing to their exceptional thermal properties and wide operational temperature ranges. HITEC, a eutectic blend of sodium nitrate, sodium nitrite, and potassium nitrate, distinguishes itself as a superior choice due to its unique amalgamation of favorable thermal characteristics. This comprehensive review delves into the thermal properties of HITEC molten salt and its manifold applications in thermal energy storage, illuminating its potential as a pivotal element in addressing contemporary global challenges. The review examines HITEC's specific heat capacity, thermal conductivity, and thermal stability, presenting critical insights into its efficacy as a TES medium. Such comprehension fosters the advancement of Sustainable Development Goal 7. The article explores strides made in HITEC-based TES systems, underscoring inventive engineering approaches and burgeoning technologies that bolster progress towards Sustainable Development Goal 9. Furthermore, the article discusses challenges associated with HITEC molten salts, such as corrosion and material compatibility issues, and investigates ongoing research efforts to overcome these limitations. A comparative evaluation of HITEC with other molten salt mixtures elucidates its competitive advantages. This review consolidates knowledge about HITEC molten salt for thermal energy storage applications, providing valuable perspectives for researchers, engineers, and policymakers dedicated to advancing sustainable energy technologies. The review underscores the pivotal role of HITEC molten salt in advancing thermal energy storage technologies, directly influencing the achievement of several SDGs.

Comparative analysis of the remineralization potential of different active ingredients based toothpastes using SEM/EDX: An in vitro study

Background/Aim: The principal purpose of this study was to investigate the efficacy of different active ingredients to inhibit demineralization around the margins of cervical cavities in natural teeth by scanning electron microscopy and energy dispersive X-Ray elemantal analysis (SEM-EDX). Material and Methods: Thirty-two sound human molars were used. Box-shaped cavities were prepared along the cemento enamel junction (CEJ). The samples were were immersed in a demineralization solution (pH=1) maintained for 72 hours and randomly divided into 4 groups. Surfaces according to the groups were treated with potassium nitrate, arginine and calciumsodiumphosphosilicate containing remineralization agents for 14 days, respectively and the samples in control group were submitted to toothbrushing with deionized water. The samples were analyzed by using SEM-EDX analysis. Data was statistically analyzed using by one way ANOVA (analysis of variance) test and LSD (least significant difference) test for comparison between means at a significance level of 0.05. Results: SEM-EDX elemental mapping was used to evaluate the degradation from depth profiles of fluoride (F), Calcium (Ca), and phosphate (P) leaching. Micromorphological and elemental analyses were done using SEM and EDX. SEM EDX Analysis on enamel showed a significant difference between the groups except the control group (p&lt;0.05). The dentine results showed significant differences between the control group and all other groups (p&lt;0.05). Elemental analysis showed significant differences in Ca weight percentage among the first and second observation levels in all groups (p&lt;0.05). Conclusions: In conclusion, all tested toothpastes showed some ability to resist demineralization at the margins. The groups except control group showed better outcomes compared with the other tested samples.

Forensic Analysis of Recrystallized Inorganic Oxidizing Salts Used in Pyrotechnic-Based Improvised Explosive Devices Using Light Microscopy and Micro-Raman Spectroscopy

This study aimed to evaluate the advantages and challenges of analyzing post-blast pyrotechnic pipe bombs using a combination of light microscopy and micro-Raman spectroscopy. Two simulated improvised explosive devices (IEDs) were constructed and exploded using pyrotechnics as the main charge and consisted of several different components to simulate common materials that might be found in authentic bombing scenarios. In order to develop a rapid explosives residue recovery technique, a wet and dry swabbing process was compared to determine the most efficient swabbing method of recovery for inorganic oxidizers in post-blast debris. Samples were recrystallized using a water recrystallization method followed by in situ analysis using polarized light microscopy (PLM) and micro-Raman spectroscopy, targeting euhedral and subhedral crystals. While the water recrystallization had effects on the resulting Raman spectrum, such as peak intensity reduction, ultimately, the final salt identifications were not affected. The detection of several inorganic oxidizers post-blast included the identification of potassium perchlorate (KClO4), potassium nitrate (KNO3), and barium nitrate (Ba(NO3)2). The detection of KNO3 using microscopy alone was more challenging due to its relatively low abundance compared to KClO4 but was achieved with micro-Raman spectroscopy. Additionally, the mixing of inorganic oxidizers within single crystals was also observed. The results indicated that the combined approach of microscopy and micro-Raman spectroscopy enabled the successful detection of inorganic oxidizing salts in a post-blast scenario, as well as describing the advantages and limitations of this combination of techniques.