Initial Content Research Articles

Zircon U-Pb geochronology and petrogenesis of Middle Eocene monzonitic plutons in NE Turkey: constraints for generation of post-collisional I-type shoshonitic magmas

ABSTRACT We present U – Pb zircon geochronology and whole-rock Sr-Nd-Pb isotopic compositions of monzonitic plutons from NE Turkey to elucidate their genesis and provide significant insights into the generation of post-collisional I-type shoshonitic magmas. Zircon U – Pb dating of the monzonitic plutons yielded an emplacement of the Middle Eocene (44–39 Ma). Geochemically, the monzonitic plutons are I-type, metaluminous, and shoshonitic in composition, and have high contents of total alkalis and LILE, high ratios of LREE/HREE and LREE/HFSE, and show negative Nb-Ta-Ti and Eu (EuN/Eu* = 0.69–0.84) anomalies. The monzonitic plutons have homogeneous and moderately low initial 87Sr/86Sr (0.70464–0.70495), positive εNd(t) values (0.33 to 1.28), and narrow variation of the initial Pb isotope contents with 206Pb/204Pb (18.74–18.82), 207Pb/204Pb (15.64–15.65), and 207Pb/204Pb (38.81–38.90). The combined use of whole-rock trace elements and isotopic compositions with regional geology suggests that parental magmas of the monzonitic plutons were generated from mainly melt-metasomatized sub-continental lithospheric mantle source and lesser crustal components in an extensional orogenic setting, and then monzonitic magmas have evolved by dominantly fractional crystallization in crustal levels.

Microstructures and properties of polymer-derived hexagonal boron nitride fibers with initial gradient oxygen contents

Oxygen plays a crucial role in the synthesis of boron nitride (BN) and the preparation of BN ceramics. The effects of oxygen content on the microstructure and properties of BN fibers treated at 1600 °C have not been studied yet. In this work, polymer-derived BN fibers are cured at 300 °C under oxygen and pyrolyzed at 600 °C, 700 °C and 800 °C under ammonia as the pre-heated BN fibers. Then, these pre-heated BN fibers are treated at 1600 °C under nitrogen as the final BN fibers. The compositions and microstructures of the pre-heated and final BN fibers are investigated. As the pre-heated temperature increases, the oxygen contents of the pre-heated BN fibers decrease to 24 wt%, 17 wt% and 5 wt%, respectively. The structures of the pre-heated BN fibers transform from amorphous BN to turbostratic BN. The oxygen in the pre-heated BN fiber volatilizes as boron oxide during treatment at 1600 °C, promoting the formation and growth of h-BN in the final BN fiber, with the maximum grain size reaching 74 × 20 nm (La × Lc). As the grain size of the final BN fiber increases, the Young's modulus, density and oxidation resistance level of the BN fiber improve, and the dielectric properties decrease. The final BN fiber that underwent pre-heating at 700 °C has the best comprehensive properties, with a tensile strength of 1.11 GPa and a Young's modulus of 265 GPa. This study researches the relationship between composition, structure and performance, and provides a scientific basis for the preparation process of BN fibers.

Initial validation of the powered mobility device autonomy residential screen (PoMoDARS)

Background The Powered Mobility Device Autonomy Residential Screen (PoMoDARS) is a new tool to enable clinicians to screen resident capacity and performance skills for powered mobility device (PMD) use in residential aged care settings. The PoMoDARS is context specific, time efficient and promotes resident autonomy and safety. Aims To (i) undertake initial face and content validation of the PoMoDARS, and (ii) use the research findings to make any modifications. Methods A mixed-methods study design, underpinned by Classical Test Theory. Eight clinicians completed 20 PoMoDARS screens and provided both quantitative and qualitative feedback on item importance and ease of use within a formal interview. Results Initial face and content validity of the PoMoDARS were supported, with small modifications made to item descriptors and instructions. Conclusions The PoMoDARS has been developed for use in residential aged care settings to screen resident PMD use. While initial validation has been undertaken, further studies to determine the reliability of the tool and continue the validation process are required. Significance Older adults in residential aged care facilities benefit greatly from the autonomy gained through PMD use. The PoMoDARS promotes collaboration between occupational therapists, nurses, and the wider team to support residents and safe PMD use.

Extreme Sn isotope fractionation in highly evolved granites

Stable Sn isotopes have been widely used to trace the planetary differentiation processes, the provenance and trade paths of ancient bronze artifacts, the mineralization history of tin ore deposits, and the terrestrial magmatic processes. However, systematic Sn isotope studies of felsic igneous rocks especially the Sn mineralization-related highly evolved granites are still lacking. In this study, we present the first high-precision Sn isotope data of two Sn-rich highly evolved S-type granites (Laochang and Kafang) from the world-class Gejiu Sn ore district. These granite samples show remarkably variable δ122/118Sn values (relative to the Sn standard solution NIST 3161a) ranging from 0.11 ± 0.02‰ to 0.93 ± 0.02‰ (2σ), which is the largest variation range reported in granites so far. The absence of correlations between Sn isotopes and LOI (loss-on-ignition) and εNd(t) values, along with the low magmatic oxygen fugacity (△FMQ < 0) for these granites, rule out hydrothermal alteration, wall-rock assimilation, source composition heterogeneity, and anatexis processes as causes of the Sn isotope fractionation. The Laochang granites show negative correlations between δ122/118Sn values and magmatic differentiation indicators (e.g., CaO, Fe2O3, Ti, Eu/Eu*, F/Cl), suggesting fractional crystallization increased the δ122/118Sn isotopes in the residual melts. The fractional crystallized minerals are mainly composed of biotite, plagioclase, and minor ilmenite. Compared with the Laochang granites, the Kafang granites show higher SiO2 contents, F/Cl ratios, and δ122/118Sn values, suggesting the magma at this stage was fluid-saturated and fluid exsolution coupled with fractional crystallization would further enrich the heavy Sn isotopes in the residual melts. We further quantified the contributions of crystal fractionation and fluid exsolution on Sn isotopic variability using a Rayleigh fractionation model. The modeling indicates that △122/118Sncrystal-melt = −0.6 to −0.5‰ and △122/118Snfluid-melt = −1.9 to −0.7‰ with an initial H2O content of 2 wt.% can explain the observed δ122/118Sn values of Gejiu granites. This study implies that both crystal fractionation and fluid exsolution processes cause increase of Sn isotopic values in the highly evolved granites and Sn isotopes are useful for tracing the evolution of highly differentiated igneous rocks.

Nanocomposite Li- and Mn-rich spinel cathodes characterized with a green, aqueous binder system

There is a growing need for alternatives to commercialized high-energy–density cathodes for Li-ion batteries with chemistries less dependent on Co and Ni and, in the past decade, particular attention has been placed on Li- and Mn- rich cathodes. Herein we report synthesis and characterization of Li- and Mn-rich cathode active materials (CAMs) with spinel-based nanocomposite structure having stoichiometries LixMn1.5Ni0.5O4 (x = 0.45–1.50) synthesized via liquid-feed flame spray pyrolysis. When cycled from 4.9 to 2.4 V, LixMn1.5Ni0.5O4 (x = 1.26, 1.50) exhibited energy densities greater than 1000 Wh kgCAM-1 using a green, aqueous binder system. Increasing initial Li content results in larger 1st charge capacity, which can potentially serve as a Li donor to irreversible, Li-consuming solid electrolyte interphase formation in next generation anode active materials.

In situ forming of PEG-NH2/dialdehyde starch Schiff-base hydrogels and their application in slow-release urea

In this study, a biodegradable Schiff-base hydrogel urea, possessing substantial water retention and certain slow-release ability was designed and synthesized. Firstly, dialdehyde starch (DAS) and amine-terminated polyethylene glycol (PEG-(NH2)2) were synthesized using potato starch and polyethylene glycol. Then, a novel Schiff-base hydrogel (SH) was prepared through the in-situ reaction between the aldehyde group of DAS and the amino group of PEG-(NH2)2. Three SH based slow-release urea, designated as SHU1, SHU2, and SHU3 and distinguished by varying urea content, were obtained using SH as the substrate. Several characterizations and tests were conducted to determine the structure, thermal properties, morphology, swelling properties, sustainable use, water retention, and biodegradation properties of SH. Additionally, the slow-release behavior of SHU was studied. SEM results revealed that SH possessed a porous three-dimensional network structure, with a maximum water absorption capacity of 4440 % ± 6.23 %. Compared to pure urea, SHU exhibited better slow-release performance after 30 days of release in soil, with SHU1 having a residual nitrogen content of specifically 36.01 ± 0.57 % of the initial nitrogen content. A pot experiment with pakchoi substantiated the water retention and plant growth promotion properties of SHU. This study demonstrated a straightforward method for the preparation of starch-based Schiff-base hydrogels as fertilizer carriers.

Anaerobic digestion of dairy cattle slurry—long-term effects on crop yields and chemical soil characteristics

Renewable energy in the form of biogas can be produced by anaerobic digestion (AD) of animal manure. However, there is still a lack of knowledge on the long-term effects of AD-treated manure on soil characteristics and crop productivity, compared with untreated manure. A field experiment was established in a perennial grass-clover ley in 2011 to study the effects on important soil and crop characteristics when the slurry from a herd of organically managed dairy cows is anaerobically digested. While the rate of manure application affected soil concentrations of extractable nutrients and pH, these variables were unaffected by AD. Soil organic matter (SOM) concentrations decreased in all plots and faster on the plots with high intrinsic SOM. The decrease was similar with application of untreated (non-digested) slurry (US) and anaerobically digested slurry (ADS), and it was not affected by application rates. The general decline may be explained by the initial high SOM content, the long-term effect of drainage, and higher temperatures with climatic change. US and ADS gave similar yields of grass-clover ley (2 cuts/year) and green fodder, on average 0.79 and 0.40 kg DM m−2, respectively. Clover yield was similar in manured treatments and the non-fertilized control. With respect to crop yields and chemical soil characteristics, long-term (10 years) effects of AD in an organic dairy cow farming system seem to be minor. The benefits of extracting energy from the slurry did not compromise grassland productivity or soil quality in the long term.Graphical

Morpho-Anatomical, Physiological and Biochemical Adjustments in Response to Heat and Drought Co-Stress in Winter Barley.

This study aimed to investigate the combined effect of high temperatures 10 °C above the optimum and water withholding during microgametogenesis on vegetative processes and determine the response of winter barley genotypes with contrasting tolerance. For this purpose, two barley varieties were analyzed to compare the effect of heat and drought co-stress on their phenology, morpho-anatomy, physiological and biochemical responses and yield constituents. Genotypic variation was observed in response to heat and drought co-stress, which was attributed to differences in anatomy, ultrastructure and physiological and metabolic processes. The co-stress-induced reduction in relative water content, total soluble protein and carbohydrate contents, photosynthetic pigment contents and photosynthetic efficiency of the sensitive Spinner variety was significantly greater than the tolerant Lambada genotype. Based on these observations, it has been concluded that the heat-and-drought stress-tolerance of the Lambada variety is related to the lower initial chlorophyll content of the leaves, the relative resistance of photosynthetic pigments towards stress-triggered degradation, retained photosynthetic parameters and better-preserved leaf ultrastructure. Understanding the key factors underlying heat and drought co-stress tolerance in barley may enable breeders to create barley varieties with improved yield stability under a changing climate.

Mechanism of the post-suffusion mechanical response of gap-graded soils from the perspective of force-chain evolution

The discrete element method (DEM) coupled with the pore-scale finite volume (PFV) method was used to simulate the suffusion and post-suffusion behavior of gap-graded soil with different initial fines content (fc). A series of drained triaxial tests were performed on the non-eroded, eroded and reconstituted samples. The results indicate that the erosion ratio (Er) increases as the fc of the sample increases. The mechanical response of the sample with an initial fc of 15 % is almost unaffected by suffusion. The dilatancy and peak deviatoric stress ratios of sample with initial fc of 25 % and 35 % are significantly lower with increasing erosion ratio. When the Er is greater than 8.2, eroded samples with an initial fc of 35 % collapse during shearing, and the eroded and reconstituted samples behave as dilation and contraction, respectively. As the initial fc increases, the mechanical response of the reconstituted samples differs more and more from that of the corresponding eroded samples. The force chain analysis indicates more force chains in the eroded sample than in the reconstituted sample, resulting in higher dilatancy of the eroded sample with fc of 25 % and 35 % during shearing.

A Commercial Clay-Based Material as a Carrier for Targeted Lysozyme Delivery in Animal Feed.

The controlled supply of bioactive molecules is a subject of debate in animal nutrition. The release of bioactive molecules in the target organ, in this case the intestine, results in improved feed, as well as having a lower environmental impact. However, the degradation of bioactive molecules' in transit in the gastrointestinal passage is still an unresolved issue. This paper discusses the feasibility of a simple and cost-effective procedure to bypass the degradation problem. A solid/liquid adsorption procedure was applied, and the operating parameters (pH, reaction time, and LY initial concentration) were studied. Lysozyme is used in this work as a representative bioactive molecule, while Adsorbo®, a commercial mixture of clay minerals and zeolites which meets current feed regulations, is used as the carrier. A maximum LY loading of 32 mgLY/gAD (LY(32)-AD) was obtained, with fixing pH in the range 7.5-8, initial LY content at 37.5 mgLY/gAD, and reaction time at 30 min. A full characterisation of the hybrid organoclay highlighted that LY molecules were homogeneously spread on the carrier's surface, where the LY-carrier interaction was mainly due to charge interaction. Preliminary release tests performed on the LY(32)-AD synthesised sample showed a higher releasing capacity, raising the pH from 3 to 7. In addition, a preliminary Trolox equivalent antioxidant capacity (TEAC) assay showed an antioxidant capacity for the LY of 1.47 ± 0.18 µmol TroloxEq/g with an inhibition percentage of 33.20 ± 3.94%.

Product contamination during mechanochemical synthesis of praziquantel co-crystal, polymeric dispersion and cyclodextrin complex

This paper aims to evaluate the product contamination by elemental impurities during the mechanochemical synthesis of praziquantel (PZQ) co-crystal, polymeric dispersion and cyclodextrin complex by grinding. To assess that, PZQ was co-ground with malic acid (MA), Poloxamer F-127 (F-127) and hydroxypropyl-β-cyclodextrin (HPβCD) in high-energy vibrational mills using stainless steel and agate grinding tools, applying different processing time (30 and 90 min). Differential scanning calorimetry and X-ray powder diffraction confirmed the formation of the targeted products, regardless of applied processing time and grinding tool type. After digestion of the solid powder products, the levels of selected elemental impurities were analysed by inductively coupled plasma mass spectrometry (ICP-MS). The analysis revealed that the content of Mg, Ca, and V are below the limit of quantification in all samples analysed. The contents of P and Na are not related to the type of ball mill and reaction time, but to the starting materials themselves, considering that Na is found in HPβCD and MA, while P was found in F-127. The detected Si impurities in the co-ground products can be related to the use of the agate balls and jars, while the presence of Cr and Fe can be related to the use of the stainless steel grinding tools. The risk assessment showed that the oral administration of the prepared co-ground products in quantities corresponding to regular PZQ oral doses resulted in only insignificant exposure to Cr. Finally, the use of agate grinding tools should be preferred, as administration of such products results in lower Cr exposure. The presented elemental impurities did not lead to any significant drug degradation as PZQ content at the end of the six-month testing period was still in the range of 95–105 % of the initial content. Regardless, ICP-MS analysis of the elemental impurities should be considered in regular quality control procedures in the development and production of novel pharmaceutical products prepared by grinding.

Global sensitivity analysis of APSIM-wheat yield predictions to model parameters and inputs

The performance of cropping system models is often limited by uncertainties in model parameters and inputs. This study aims to explore how model yield prediction responds to these uncertainties under various environmental and management conditions. The Sobol’ method was used to investigate the sensitivity of the Agricultural Production Systems SIMulator (APSIM)-Wheat yield prediction to the following factors: air temperature (maximum and minimum), precipitation, initial soil nitrogen content, nitrogen fertilization amount, and soil hydraulic parameters. Eighteen scenarios were defined to consider a combination of three weather conditions (wet, normal, and dry growing season, based on the historical climatology of the Wimmera district of Victoria, Australia), three soil types (sandy, loamy, and clayey soils), and two nitrogen fertilization applications (50 and 100 kg N/ha). Eight thousand APSIM simulations were used to calculate the first order and total sensitivity indices for each scenario. The effects of weather, soil water characteristics and nitrogen availability were estimated by measuring their impacts on sensitivity indices. Our results show that yield was more sensitive either to variables that control water availability (precipitation and soil type) or variables that control nitrogen availability, depending on which was more limiting to wheat growth under the scenario. For example, in case of low nitrogen fertilization scenario, the initial nitrogen content sensitivity ranked first. Variation of this factor contributed 64% to 79% to the variance in simulated yield for clayey soils, nearly four times higher than the second-ranked factor (nitrogen fertilization amount). Soil hydraulic parameters and precipitation were most important when the crop growth was more constrained by water availability than by nitrogen availability. In the case of sandy soils in dry years with high nitrogen fertilization level, soil parameters and precipitation accounted for 83% of the yield variability. Minimum temperature consistently ranked as the least important factor under all scenarios. This work will help researchers better understand the model inputs’ impacts on the simulated yield variability under various soil, management, and weather conditions. The results also support agronomists and practitioners in the optimal use of the APSIM-Wheat model as a management tool.

Reduction of Aflatoxin contamination in coconut oil using concentrated solar radiation

Global demand for edible coconut oil has a rapid growth due to its health benefits. However, the susceptibility to carcinogenic mold contamination, aflatoxin, poses a significant global health concern. Concentrated solar radiation was used in this study as a new initiative to investigate the more efficient elimination of aflatoxin in coconut oil. Samples were collected from the Colombo district, Sri Lanka, as branded (n = 3) and unbranded (n = 5). The initial aflatoxin content was determined using High-Performance Liquid Chromatography (HPLC-FLD) system with AflaStarTM FIT immunoaffinity columns. They were exposed to concentrated solar radiation for 10 (T-1), 20 (T-2), and 30 (T-3) minutes respectively, using a parabolic proto-type solar concentrator. The remaining aflatoxin content was re-determined after each treatment. Following each treatment (T-1, T-2 and T-3), the maximum allowed total Aflatoxin and Aflatoxin B1 (AFB1) content of all coconut oil samples were lower than the set European Union (EU) limits (4.2 µg/kg) with a mean total Aflatoxin reduction of 94.00 ± 6.48 %, 98.67 ± 2.80 %, 100.00 ± 0.00 % respectively. T-1 and T-2 treatments at mean concentrated solar radiation levels (W/m2) of 971 ± 29 and 945 ± 65.4 were recognized as the most efficient at removing total and AFB1 aflatoxin tainted in coconut oil at higher levels.

The effect of aeration rate and feedstock density on biodrying performance for wet refuse-derived fuel quality improvement

This study investigates the effect of aeration rate and feedstock density on the biodrying process to improve the quality of type 2 wet refuse-derived fuel. The aeration rate and feedstock density were varied to investigate these parameters’ effect on the system’s performance. The experiments used 0.3 m3 lysimeters with continuous negative ventilation and five days of operation. In Experiment A, aeration rates of 0.4, 0.5, and 0.6 m3/kg/day were tested with a feedstock bulk density of 232 kg/m3. In Experiment B, the optimum aeration rates determined in Experiment A (0.5 and 0.6 m3/kg/day) were used, and the feedstock density was varied (232 kg/m3, 250 kg/m3, and 270 kg/m3). The results showed that an aeration rate of 0.5 m3/kg/day was the most efficient for a feedstock density of 232 kg/m3; when the aeration rate was increased to 0.6 m3/kg/day, a feedstock density of 250 kg/m3 was the most effective. However, a feedstock density of 270 kg/m3 was not found to be practical for use in the quality improvement system. When the feedstock density is increased, the water in the feedstock and the water resulting from the biodegradation process cannot evaporate due to the feedstock layer’s low porosity, and the system requires an increased aeration rate. Furthermore, the increase in density scaled with increased initial volatile solid content, initial organic content, and initial moisture content, which significantly impacted the final moisture content based on multivariate regression analysis.

Parametric investigation and optimization in laser based directed energy deposition of tungsten carbide-cobalt

Cemented carbide (WC-Co), the widely used tool-die material, is difficult to be machined by conventional and nonconventional techniques. This inspired exploring additive manufacturing (AM) of this material. However, porosity, brittleness due to cobalt depletion, etc. have been reported in the literature with rare success. For the AM of WC-Co, the current work focuses on directed energy deposition, which can be implemented with existing laser cutting-welding workstations, with modifications. To ensure the retention of cobalt even after inevitable vaporization of some of its initial content during deposition, 20 wt. % of Co was mixed with WC powder by low-energy ball milling. Laser power, scan speed, and powder flow rate were varied following a full-factorial design of experiments. The analysis of variance revealed that the experimental model and most of the parameters were significant. Only the laser power came out to be insignificant for the contact angle. The track height and width increased with the laser power and reduced with the scan speed. The contact angle increased with the scan speed and reduced with the powder flow rate. Cross sections of the deposited track showed no pores or cracks. Multiobjective optimization with gray relational analysis was conducted to get the parameter combination giving high values of the contact angle, track height, and width simultaneously. The optimum parameter combination, thus, obtained is 700 W laser power, 5 mm/s scan speed, and 5 g/min powder flow rate. This yielded 305 ± 40 μm track height, 2132 ± 33 μm width, and 152° ± 2° contact angle.

Investigation of wine fermentation of three-leaf cayratia (Cayratia trifolia L.) using Saccharomyces cerevisiae 2.1

Background: Cayratia trifolia has been extensively studied for its bioactive components and medicinal properties. This study was carried out to evaluate the fermentation ability of Saccharomyces cerevisiae 2.1 yeast to determine suitable fermentation conditions. Methods: The initial sugar content for three-leaf cayratia fermentation and fermentation efficiency were calculated. The temperature for three-leaf cayratia fermentation, incubation time, and preliminary 1 liter of three-leaf cayratia wine fermentation were determined. All treatments showed that the total sugar content decreased after 9 days of fermentation compared to the initial level. Temperature during fermentation has a direct effect on yeast activity. Temperature increases the growth of yeast and speed of enzyme activity. The fermentation time changes depending on temperature, initial soluble solid contents, and yeast strains, leading to changes in the ethanol content after the end of fermentation. Results:The results showed that the S. cerevisiae 2.1 strain was able to ferment at room temperature with an initial pH of 4.5, 24 °Brix, and a yeast density of 107 cells/mL. The appropriate fermentation conditions determined for S. cerevisiae 2.1 yeast were 24 °Brix and incubation at room temperature (28-33°C) with a fermentation time of 11 days. Concusion: In 1 liter scale fermentation, three-leaf cayratia wine had 9.46% (v/v) and the fermentation efficiency was 90.34%. The wine produced had a unique color, flavor, and aroma that met the sensory evaluation of the Vietnamese standard TCVN-3217:79.

Influences of alloying composition and cooling rate on precipitation behaviors of primary Al3Zr-D023 intermetallics in Al-Mg-Li-Zr alloys

In the industrial process, the potential benefit of Al3Zr precipitates is usually weakened because coarse Al3Zr precipitates have no positive effect on the dynamic recovery, recrystallization and grain growth. Effects of alloying composition and cooling rate on precipitation and growth behaviors of primary Al3Zr-D023 intermetallics were investigated, especially in a large compositional space. Four types of elements exist in the Al3Zr-D023 phase. Increasing initial Mg, Li, Zr, and Ti contents is beneficial to increase the start precipitation temperature of Al3Zr-D023 particles. Increasing initial Mg, Li, Zr, Ti contents and reducing cooling rate are beneficial to increase the mean length, decrease the nucleation rate and the number density of Al3Zr-D023 precipitates. Furthermore, Zr and Ti element contents show a strong positive correlation with the start precipitation temperature and the final length of Al3Zr-D023 precipitates. Reducing slightly initial Ti content is beneficial to reduce the final length of Al3Zr-D023 precipitates. Furthermore, two empirical equations were obtained using the multiple linear regression method, which reveal the complex interactions rather than single-element effect of Mg, Li, Zr, and Ti.

Phosphate Recovery from Urine-Equivalent Solutions for Fertilizer Production for Plant Growth.

This study presents a proof of concept for the recovery of phosphate from aqueous solutions with high phosphorus (PO4-P) initial contents to simulate the concentration of streams from decentralized wastewater systems. Solutions with ∼500 ppm phosphorus enable phosphate adsorption and recovery, in contrast to the highly diluted inlet streams (<10 ppm) from centralized wastewater treatment plants. In this work, Mg-Fe layered double hydroxide is used as a phosphate adsorbent, demonstrating its separation from aqueous streams, recovery, and use as a fertilizer following the principles of circular economy. We demonstrate that the mechanism of phosphate adsorption in this material is by a combination of surface complexation and electrostatic attraction. After the loss of crystallinity in the presence of water in the first cycle and its associated decrease in adsorption capacity, the Mg-Fe layered double hydroxide (LDH) is stable after consecutive adsorption/desorption cycles, where desorption solutions were reused to substantially increase the final phosphate concentration demonstrating the recyclability of the material in a semicontinuous process. Phosphate recovered in this way was used to complement phosphate-deficient plant growth medium, demonstrating its efficacy as a fertilizer and thereby promoting a circular and sustainable economy.

Effect of cooking methods on the nutritional quality of selected vegetables at Sylhet City

The study was carried out to analyze the impacts of boiling, steaming, and microwave cooking on the physicochemical properties, the content of bioactive compounds, and boiling effect on mineral and heavy metal content of six widely consumed vegetables in Bangladesh's north-eastern region. In comparison to raw, boiled, and microwave-cooked vegetables, those that are steam-cooked retain a higher percentage of β-carotene with the exception of carrots. Boiling vegetables led to the most substantial reduction in ascorbic acid content (from 9.83 % to 70.88 %), with spinach experiencing the greatest decline. In contrast, microwaving had the mildest effect on ascorbic acid, preserving over 90 % of the initial content. The decrease in carotene content may be associated with color changes (decreasing greenness and increasing hue angle) in the chosen vegetables. The colorimeter shows the L* value (lightness/darkness) of all cooked vegetables significantly decreased. In terms of total polyphenol content (TPC) and total flavonoid content (TFC), boiling had a higher negative effect on most vegetables than the other two cooking methods, with losses of up to 70.3 % and 82.27 %, respectively. All cooked vegetables, with the exception of carrot and microwave pumpkin, had substantial reductions in free radicals scavenging activity, with losses ranging from 8.48 % to 56.73 %. In comparison to raw vegetables, boiled vegetables significantly lost minerals like potassium (K), magnesium (Mg), zinc (Zn), copper (Cu), and manganese (Mn). On the other hand, the calcium (Ca) and iron (Fe) content of all cooked vegetables, except for carrots and peas, exhibited an increase, ranging from 6 to 17 % and 6–12 %, respectively. The Cr concentration in all vegetables and the Zn, Fe, Mn, and Cd content in the spinach sample was higher than the FAO/WHO recommended maximum permissible level (MPL), whereas the accumulation of Cu and Ni content was lower in all vegetables. In conclusion, this study demonstrated that microwaving was the most effective method for retaining the nutritional value of vegetables, while steaming had a moderate impact.

Efficient separation of indole from fossil fuel pyrolysis products by carboxylic acid non-aromatic ring ionic liquids: Experiment and mechanism exploration

Indole is a nitrogen-containing compound that is obtained from fossil fuel pyrolysis products. Its usage is not only related to the production of fine chemicals and medicines, but it also has the potential to benefit environmental protection. To separate indole through liquid–liquid extraction with ionic liquids, two types of carboxylic acid non-aromatic ring ionic liquids (CNILs) were successfully synthesized and characterized in this work. The effects of stirring time, mCNILs: mmixtures, and extraction temperature were extensively investigated in this work. The results indicate that the adopted CNIL, [N-tmg][Bpc], which processes multifunctional sites, exhibited better extraction performance for indole. Under the optimized conditions (mCNILs: mmixtures = 1:5, temperature, 25 °C, stirring time, 30 min) and initial indole content, mindole: moil = 5:100, the extraction efficiency of indole was found to be 97.08% using the CNIL [N-tmg][Bpc]. Additionally, the molecular polarity, bond length, interaction energy, and non-covalent interaction were evaluated via quantum chemistry calculation, and found that the non-covalent interaction between the CNIL anions and indole was the primary driver of extraction, and the multifunctional sites in CNIL anions improved the ability of CNILs to extract indole. Finally, the reusability of CNIL, [N-tmg][Bpc], was tested through repeated extraction experiments, and the recovered [N-tmg][Bpc] was found to efficiently extract indole. The successful synthesis of CNILs with high extraction performance for indole provides a novel route to develop new ionic liquid separation agents. The finding in this work contributes to the chemical industry's efforts to develop appropriate and sustainable technologies for indole separation.