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This paper investigates the impact of annealing temperature on the photocatalytic degradation efficiency of rhodamine B (rhB) using a montmorillonite/zinc-oxide (MMT/ZnO) nanocomposite. The MMT/ZnO nanocomposites, synthesized through a chemical method, are annealed for one hour at 300°C, 500°C, and 700°C. The study involves a comprehensive analysis of sample composition, surface morphology, and structure using various analytical methods, including Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, and Fourier Transform Infrared Spectroscopy (FTIR). RhB degradation efficiency is assessed by monitoring changes in dye concentration in the solution after exposure to UVC radiation, measured with UV-Vis spectroscopy. By-products resulting from the photocatalysis process are identified through LCMS analysis. The results demonstrate that MMT/ZnO annealed at 500°C (referred to as MZ@500) exhibits the highest capability for rhB decomposition, achieving a remarkable 95.5% degradation efficiency with 10 ppm of rhB and 0.1 g/L of MZ@500. Furthermore, this composite effectively fragments the dye's chromophore structure into smaller, ring-broken compounds.

This study aims to synthesize a nanocomposite photocatalyst from naturally sourced clay (montmorillonite, MMT) and titanium dioxide nanotubes (TNTs) to efficiently degrade organic dyes in wastewater under UVC light. The TNTs were synthesized through the hydrothermal method and were randomly attached to both the surface and interlayer spaces of the MMT sheets. Pristine MMT was found to exhibit good adsorption properties, while the TNTs demonstrated strong photocatalytic activity. The combination of these materials in the MMT/TNT nanocomposite resulted in a material that exhibited both adsorption and photocatalytic properties. The dye degradation efficiency of the MMT/TNT nanocomposite reached 95%, which is significantly higher than that of pristine MMT (50%) and TNTs alone (60%). This enhanced performance can be attributed to the synergistic effect between the adsorption capacity of MMT and the photocatalytic activity of TNTs. The study highlights the potential of using naturally sourced materials like MMT in the development of advanced photocatalysts for environmental remediation. The MMT/TNT nanocomposite offers a sustainable and efficient solution for the removal of organic pollutants from wastewater. These findings provide a pathway for further development of high-performance nanocomposites that combine the dual functional properties of adsorption and photocatalysis, contributing to more efficient wastewater treatment technologies.

Chemical conversion of natural graphite into graphene based nanomaterials is achievable and scalable by designed Hummers’ method. Conventionally, high amount of manganyl compound (Mn2O7 or MnO3+) and explosive risk of thermal runaway in the reaction are still the key concerns of efficiency and safety in the production technology. In this manuscript, reaction mechanism and innovative strategy are applied in the cascade design of graphite oxide synthesis. By optimizing the amounts of reactive chemicals (KMnO4, H2SO4 and water), utilizing exothermic energy (for self-heating reaction and exfoliation) and combining reaction divisions (for control of thermal runaway), the principal issues of safety and efficiency are improved for simple and practical preparation of graphene oxide nanomaterials. The cascade synthesis occurs in just 8 h without external supply of thermal energy, producing solid yield of more than 130%wt. Obtained graphene oxide nanosheets have good colloidal property, uniform decoration of functional groups, appropriate C/O atomic ratio of 1.62 and optoelectronic band gap energy of 3.33 eV. Characterization of graphene oxide membranes showed elemental oxygen mapping, C/O atomic ratio of 2.12, ultimate tensile strength of 59.17 MPa and strong elastic modulus of 10.123 GPa. Hydrogel of partially reduced graphene oxide was prepared and analyzed, revealing the C/O atomic ratio of 2.63 and band gap energy of 2.88 eV. The technological improvements open a safe and efficient route of graphene oxide production for scientific and industrial purposes.

This study investigated the effects of concentrate levels and oil supplementation on rumen characteristics and growth performance of cattle. Twenty-four Brahman crossbred bulls were arranged in a 2×3 factorial design with two levels of concentrate (0.5 and 1.5% body weight) and three supplemental sources (60 g soybean oil/kg dry matter (DM), 60 g fish oil/kg DM and non-oil). Total rumen bacteria number was higher in cattle fed diets with lower concentrate level (P=0.05), yet it was not affected by oil supplementation. Acetic and butyric acid concentration in rumen decreased with the increase of concentrate level in diet. The intake of total DM and crude protein were higher in cattle fed higher concentrate diet (6.25 kg/day and 778 g/day, respectively). In terms of growth performance, the higher concentrate level cattle consumed, the better weight gain was achieved (768 g/day). Soybean oil addition helped attain the highest weight gain of 738 g/day, while similar weight increase was observed in cattle fed non-oil and fish oil supplemented diets (624 g/day and 641 g/day, respectively). Supplementation of concentrate and oil also increased weight gain and the maximum daily weight gain (851 g/day) was recorded in cattle fed the diet containing soybean oil combined with 1.5% concentrate. [ABSTRACT FROM AUTHOR]

The speciation of a particular element in any given matrix is a prerequisite to understanding its solubility and leaching properties. In this context, speciation of uranium in lanthanum zirconate pyrochlore (La2Zr2O7 = LZO), prepared by a low-temperature combustion route, was carried out using a simple photoluminescence lifetime technique. The LZO matrix is considered to be a potential ceramic host for fixing nuclear and actinide waste products generated during the nuclear fuel cycle. Special emphasis has been given to understanding the dynamics of the uranium species in the host as a function of annealing temperature and concentration. It was found that, in the LZO host, uranium is stabilized as the commonly encountered uranyl species (UO22+) up to a heat treatment of 500 °C at the surface. Above 500 °C, the uranyl ion is diffused into the matrix as the more symmetric octahedral uranate species (UO66-). The uranate ions thus formed replace the six-coordinated 'Zr' atoms at regular lattice positions. Further, it was observed that concentration quenching takes place beyond 5 mol% of uranium doping. The mechanism of the quenching was found to be a multipolar interaction. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate leptin (LEP) gene polymorphisms in crossbred Holstein Friesian (HF) x Lai Sind cattle and their effects on milk yield and milk quality traits. Milk yield was recorded for lactation period of 305 days. Milk fat and protein were estimated using the Milko Tester machine. DNA extracted from blood samples (n=206) was amplified by PCR technique followed by sequencing for single nucleotide polymorphism (SNP) identification. Applied genotyping for the two SNPs (g.C1180T and g.C2059T) was done by PCR-RFLP method with the presence of Kpn2I and Sau3Al restriction enzymes, respectively. At the LEP/Kpn2I locus, cows of CT genotype accounted for the highest proportion (78%) whereas at the second SNP, the frequency of CC dominated (63%). In the association analysis, the LEP/Kpn2l polymorphism did not affect 305-day milk yield, but showed significant influence on milk quality traits, of which cows with CT genotype had higher protein (3.67%) and fat (3.99%) content than ones with CC and TT. The other locus (LEP/Sau3Al) was not associated with any traits analyzed. In conclusion, the g.C1180T SNP could be included in marker assisted selection of crossbred HF cows for improving protein and fat percentages. [ABSTRACT FROM AUTHOR]

Energy dispersive X-ray fluorescence (EDXRF) spectrometric methods have been developed for the determination of some common metallic impurities in ThO2 matrix. A series of ThO2 standards containing the analyte impurities in the range 10–100 (or 100–500) μg/g was prepared synthetically. The spectrometer conditions were optimized to obtain calibration plots for the various analytes. The accuracy and precision of the developed methodology for regular assay of ThO2 was evaluated by analyzing three synthetic samples. Further three secondary ThO2 standards were analyzed by EDRXF to check the developed methods. The determined concentrations of Ca, Cr, Fe, Ni and Cu were in good agreement with the certified values of the secondary standards. [ABSTRACT FROM AUTHOR]