La2CuO4@x%CuO (x = 0, 10, 20, 30) nanocomposites were synthesized via glycine-nitrate combustion method employing excess fuel and investigated as multifunctional catalysts for environmental applications. This study reports, for the first time, the nitroaromatic reduction and degradation of organic dye effluent capabilities of Ruddlesden-Popper oxides coupled with CuO. Structural studies confirmed orthorhombic La2CuO4 (Bmab) with successful CuO incorporation. Furthermore, the materials exhibited good thermal stability, nanoscale morphology, and compositional purity as evidenced by TGA, FE-SEM and XPS studies. Nitroaromatic reduction catalysed by La2CuO4@20%CuO was governed primarily by pore size rather than surface area. Pristine La2CuO4 showed enhanced visible-light absorption and lower recombination rates, as optical analysis revealed an increase in band gap with CuO addition, thereby, promoting efficient charge utilization. As a multifunctional catalyst for environmental applications, La2CuO4 achieved similar to 99% RhB degradation under visible-light irradiation, while the La2CuO4@20%CuO composite exhibited superior nitroaromatic reduction due to improved pore-assisted mass transport. The phases remained structurally intact even after five consecutive degradation and reduction cycles, as confirmed by P-XRD, demonstrating the excellent durability and versatility of the synthesized nanocomposites.

In this study, nanostructured NiAlFeO4 ferrite catalysts were synthesised by varying pH and systematically characterized to evaluate their structural, magnetic, optical, and photocatalytic properties. X-ray diffraction (XRD) investigation confirmed the formation of a pure cubic spinel phase with Fd3m space group and nanoscale crystallite size. Nitrogen adsorption-desorption (BET) studies revealed that NAFO-2 possessed the highest surface area (48.2 m2/g) and pore volume (0.143 cm3/g), which facilitated enhanced adsorption and diffusion of reactants. Magnetic measurements at 10 K and 300 K showed that all samples exhibited ferrimagnetic behaviour at low temperatures and soft magnetic, near-superparamagnetic characteristics at room temperature, with NAFO-2 displaying the highest saturation magnetisation. Zero-Field-Cooled (ZFC) and Field-Cooled (FC) magnetisation profiles indicated the absence of a sharp blocking temperature, confirming the presence of thermally active magnetic moments and high-temperature magnetic ordering. Despite the lowest Photoluminescence (PL) emission intensity and hence efficient charge carrier separation, NAFO-1 exhibited lower photocatalytic activity than NAFO-2. Photocatalytic activity was assessed by degrading RhB dye under visible light in the presence of H2O2. NAFO-2 achieved the highest degradation efficiency, attributed to its optimal surface textural properties and magnetic behaviour. Control experiments and mechanistic evaluation confirmed a heterogeneous photo-Fentonlike pathway, with reactive oxygen species such as OH center dot and O2 center dot- playing a dominant role. These findings demonstrate the potential of NAFO ferrites as efficient, magnetically recoverable photocatalysts for advanced wastewater treatment applications.

The study of phase-separated metallic glasses (PSMGs) is motivated by both theoretical curiosity and their potential practical applications. It offers important understanding of the atomic arrangement and properties of disordered materials, while also giving new pathways for developing advanced materials with tailored properties. PSMGs exhibit unique structural and physical characteristics that distinguish them from monolithic metallic glasses (MGs), allowing for enhanced mechanical, thermal, and chemical performance. Recent advances in synthesizing PSMGs have paved the way for engineering materials with hierarchical microstructures across multiple length scales, enabling the design of novel composites with optimized strength, ductility, corrosion resistance, and other desirable properties. This chapter presents an in-depth exploration of nanoscale phase separation in MGs, emphasizing its influence on material properties. The discussion is organized into two main units. The first unit provides a brief overview to phase separation in MGs, discussing the underlying mechanisms, microstructural evolution, thermal behavior, and the advantages of phase-separated structures. It also highlights selected findings related to their morphology and properties. The second unit discusses recent advances in Zr-based PSMGs with respect to their design and properties. This also includes the new results of in-situ transmission electron microscopy (TEM) tensile deformation and corrosion tests of phase-separated Zr–Al–Fe–Y MG compositions, which have not been reported so far.

ABSTRACT In the present work, a Cr 3+ ‐modified n = 2 RP ferrite, La 2 SrFeCrO 7 , was successfully synthesized using a Pechini‐type sol–gel method. Structural analysis using Rietveld refinement of PXRD data confirmed the formation of a single‐phase tetragonal RP structure (space group I4/mmm ), with lattice contraction reflecting the incorporation of smaller Cr 3+ ions at the B site. Optical studies revealed a significant red shift in absorption and a band gap of 1.55 eV, making the material responsive to visible light. Magnetic investigations showed predominantly antiferromagnetic ordering accompanied by weak ferromagnetism, originating from competing super‐exchange interactions involving Fe 3+ and Cr 3+ ions. The photocatalytic performance was evaluated through the degradation of a number of dyes. Complete photocatalytic degradation was attained within 70 min for MO, 100 min for RhB, 130 min for MB, and 140 min for the mixed dye system. Furthermore, kinetic investigations revealed that the rate constants follow the sequence: MO > RhB > MB, which correlates well with the experimentally observed photocatalytic degradation behavior. The photocatalytic activity is attributed to improved visible‐light absorption, effective charge separation, and Cr 3+ ‐assisted photo‐Fenton reactions. The superior photocatalytic activity of La 2 SrFeCrO 7 toward the degradation of both individual and mixed dye pollutants highlights its potential for advanced wastewater remediation.

This work investigates the effect of supported iron-oxide nano-catalysts for hydrothermal conversion of food waste. The studied supports were Vulcan carbon (VC), CeO2, ZSM-5 and amorphous SiO2-Al2O3. Catalytic hydrothermal liquefaction experiments were carried out in a batch reactor at 16 MPa and 300 degrees C maintained for 1 h. Different fractions of Fe(0), Fe2+ and Fe3+ alter its tendency toward deoxygenation, hydrogenations and condensation reactions, which influence the bio-crude yield, elemental compositions, and energy recoveries. The fresh and spent catalysts were characterized using X-ray photoelectron spectroscopy, physisorption analysis, thermogravimetric analysis, transmission and scanning electron microscopy. It was found that the change in catalyst support influences HTL pathways and product compositions. The results reveal that the inclusion of FeOx catalyst on Vulcan carbon, SiO2-Al2O3 and ZSM-5 supports can increase the bio-crude yield by similar to 7-9 wt% compared to their FeOx-free yields. The increase in bio-crude yield was associated with the decrease in the surface ratios of Fe3+/Fe2+ at the range of 0.8-1.6. In overall, catalysts that had higher tendencies in converting amines into oil-soluble compounds increased the bio-crude yield, while catalysts that promoted dehydration and decarboxylation route decreased the bio-crude yield. The maximum energy recovery in bio-crude was obtained using FeOx/SiO2-Al2O3 catalyst with values similar to 95 %. The deactivation of catalysts was associated with the increase in Ca and P poisonous elements on catalytic sites, which decreased the energy recovery of recycled FeOx/SiO2-Al2O3 to similar to 85 % after three cycles.

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The current study describes the synthesis of the perovskite manganite La 0.8 Ca 0.15 Na 0.05 Mn 0.8 Fe 0.2 O 3 using Pechini method. The Rietveld analysis of the powder X-ray diffraction data verified the presence of a single phase exhibiting orthorhombic symmetry with the Pnma space group. The phase undergoes a shift from paramagnetism to ferromagnetism when the temperature reaches the Curie temperature of 111 K. A positive Weiss constant ( Theta ) and a greater effective magnetic moment than the anticipated value suggests the presence of dominating ferromagnetic interactions in the phase.

Ongoing research emphasizes the vital role of advanced scientific knowledge in addressing complex wastewater management challenges. Efficient catalysts for degrading pollutants like nitrophenols and organic dyes are crucial for sustainable water quality, resource preservation, and cost-effective solutions. Herein, highly stable and magnetically recoverable Bi3+-doped Ni–Cu–Cr quinary spinel ferrite nanoparticles, synthesized using sol–gel technology, were proposed as heterogeneous nanocatalysts for removing pollutants like nitrophenols and dyes from wastewater. The optical band gap values obtained from DRS lies in the visible range (1.35–1.60 eV) making them suitable and reliable photocatalysts. The augmentation in BET surface area observed with the escalating Bi3+ doping levels signifies an increased availability of active sites conducive to facilitating reactions. Moreover, all the Ni–Cu–Cr ferrites show tremendous results in the reduction of 4-NP and photocatalytic degradation of RhB, but the BF-4 nanocatalyst exhibits the best results among all the other catalysts (reduction of 4-NP and degradation of RhB was 99% completed in 21 and 40 min, respectively). Considering the above fascinating results, we have also extended our scope of work for the reduction of 2-NP, 3-NP, and 2,4,6-TNP and degradation of MB, MO, and a mixture of all organic dyes, i.e., RhB + MB + MO. It was observed that BF-4 swiftly reduces as well as degrades all types of pollutants in the shortest period of time confirming the versatility of our BF-4 nanocatalyst. Moreover, we delved into the degradation mechanism of dyes by investigating the impact of active species, including O2–• and OH• through scavenging experiments, and as a result, OH• was identified as the main contributor to the degradation of dyes. As indicated by the VSM studies, the BF-4 nanocatalyst was easily recoverable using an external magnet and can be used again for recycling reactions. In the context of wastewater management and water resource preservation, our Bi3+-doped Ni–Cu–Cr quinary ferrites stand out as ideal candidates. Their exceptional stability and robust catalytic activity make them a top choice for effectively removing and degrading a wide range of pollutants, contributing to the improvement of water quality and the sustainable management of water resources.

Flory's statistical theory (FST) has been employed to estimate the ultrasonic velocity, density, internal pressure, and several important thermophysical parameters such as the energy of vaporization, the heat of vaporization, cohesive energy density, polarity index, and solubility for eight binary mixtures of ionic liquids and water within the temperature range of 288.15 to 308.15 K. The ionic liquids chosen for this investigation are [BMim][dca], [BMim][TfO], [BMpy][TfO], [BMpyr][dca], [BMpyr][TfO], [EEPy][ESO4], [HMim][dca], and [MPy][MSO4]. The predicted values of ultrasonic velocity and density show good agreement with the data reported in the literature. It endorses the applicability of FST to these binary mixtures. A comparative analysis of the internal pressure values (Pi) determined by using FST and the standard thermodynamic approach is also presented. The results obtained for Pi using both approaches show good agreement. Besides, for the mixtures under study, the correlation between ultrasonic velocity, density, and surface tension has also been examined. The variation of thermophysical parameters with concentration and temperature changes has been utilized to explore the nature and strength of the solute-solvent interactions prevalent in these mixtures. It is pointed out that A-A-type interactions dominate over A-B-type interactions in water-rich regions of the mixtures.

Flory's Statistical Theory (FST) has been applied to investigate excess thermodynamical parameters viz., excess enthalpy, excess entropy, and excess Gibbs free energy for eight binary mixtures of ionic liquids and water at different concentration and temperatures. The concentration and temperature dependent variations of excess enthalpy suggest that ionic liquid mixtures exhibit an endothermic nature and the presence of weak dispersive forces among their constituents. The positive excess Gibbs free energy of mixing points out that the pure components do not mix thoroughly for the systems under study. Overall, these binary systems are thermodynamically unfavorable suggesting that the mixing of ionic liquids and water is not energetically favored or spontaneous. Experimental molar volumes are compared with those calculated using FST and these values show excellent agreement. It affirms the validity of FST's application to these systems. Additionally, some partial properties have also been determined to explore the solute-solvent interactions. The Redlich-Kister (R-K) polynomial model has been applied to excess thermodynamical parameters The high R2 values and low standard deviation values confirm the validity of fitting the RK polynomial model to the functions obtained using FST of liquids for these systems within the given temperature range. image

This article examines electrical properties of fullerene (C70) based all-small-molecule organic photovoltaics with low donor concentration. Enhancements in the properties of devices are observed with the incorporation of lithium fluoride (LiF) and molybdenum trioxide (MoO3) as cathode buffer layers (CBLs). Samples are characterized using field emission-scanning electron microscopy (FESEM), optical absorption spectra, current-voltage (I-V) characteristics in dark and under illumination, and capacitance-frequency (C-omega) measurements. Device with single CBL (LiF) exhibits reduced photoabsorption leading to less saturation photocurrent density (Jsat) and lower maximum exciton generation rate (Gmax), due to non-uniform deposition of LiF in device. In contrast, device having two CBLs (LiF & MoO3) has enhanced the photoabsorption exhibiting high Jsat and Gmax attributed to uniform deposition of MoO3. Moreover, dielectric properties and AC conductivity of devices are also measured confirming the results and these are found to be dependent on the frequency and voltage.

Background: Cowpea is an important fodder legume crop due to its high protein content and fast growing nature. Cowpea can be grown as sole crop or it can also be grown as intercrop with some non legume such as maize, pearl millet or sorghum. Mostly the farmers prefer erect or semi erect high yielding cowpea varieties as an intercrop because they are easy to harvest. The transfer of erectness along with other forage traits can be done with proper knowledge of gene action controlling that particular trait. Methods: To improve the fodder yield, two sets of crosses along with their segregating generations were analysed for erectness along with other forage traits to estimate the type of gene action through generation mean analysis. Identification of SSR primers associated with erectness was also carried out in F2 population of a Cross (C-88 x TNFC 6926). Result: The scaling test showed significant results for most of the traits indicating the presence of epistatic interactions. The six-parametric model test was performed and the results indicated the significant overall mean and traits were inherited quantitatively. The high magnitude of additive x additive gene effect for green fodder yield suggests the pedigree method is most suitable breeding programme for development of fodder cultivars with better quality traits. Out of 151 SSR primers, 15 SSRSs showed polymorphism between two parental lines. Out of these 15 SSR primers, three primers showed linkage with erectness.

Shoot fly is a devastating pest and causes a serious threat to sorghum. In the present investigation, oxidative enzymes, guaiacol peroxidase (GPX), tyrosine ammonia lyase (TAL) and biochemical metabolites were studied for shoot fly resistance in six sorghum genotypes at 15 and 21 days after emergence (DAE). The plant material had been categorized into resistant genotypes (IS18551, ICSV705, and ICSV700), moderately resistant genotype (PSC-4) and susceptible genotypes ( SWARNA and SL-44) on the basis of observed shoot fly resistance. All the enzymes showed an upregulated trend in their activity with shoot fly infestation. The oxidative enzymes diamine oxidase (DAO) and polyamine oxidase (PAO) upregulated to 1.6 fold and 2.0 fold in susceptible genotypes. Ascorbate oxidase (AOX) activity was also higher in resistant genotypes at 21 DAE. The increased production of H 2 O 2 by PAO and DAO led to the activation of the H 2 O 2 -metabolising enzyme GPX by 3.5 fold and 2.0 fold in leaf and stem tissue of susceptible genotypes as compared to resistant genotypes at both sampling stages. The response of the phenylpropanoid pathway enzyme TAL was upregulated more in leaf of the resistant genotype ICSV705 (2.12 fold) at 21 DAE leading to production of phenolic constituents viz . flavanols and condensed tannin. These key enzymes along with oxidative enzymes enable the resistant genotypes to tolerate the biotic stress as evident from the lower content of thiobarbituric acid reactive substance (TBRAS) in resistant genotypes compared to the susceptible ones.

In this investigation, the spatiotemporal distribution of cyanobacteria and their relationships with variations in water chemistry (physico-chemical parameters and heavy metal) of Sutlej River, Punjab (India) has been analyzed by employing multivariate statistical methods. Sutlej River exhibits a rich array of cyanobacterial diversity, comprising 28 species across 15 genera, distributed among 11 families and spanning 5 orders within the class Cyanophyceae. In terms of relative abundance, Microcystis aeruginosa (17.47%) was documented as the most abundant taxa followed by Microcystis robusta (16.55%), Merismopedia punctata (11.03%), Arthrospira fusiformis (6.67%) and Pseudanabaena galeata (3.68%). Significant variations were observed among sampling sites in most of the physico-chemical parameters. Principal Component Analysis delineated sampling sites into two discernible groups according to variations in water chemistry. River Pollution Index (RPI) showed that river water is under the unpolluted (RPI 1.5) to negligibly polluted category in the upstream sites, while moderately polluted (RPI 5.5) in the downstream sites. Heavy metal Pollution Index (HPI) revealed consistent heavy metal contamination at sites RWS7 and RWS8 across all seasons. Conversely, site RWS1 consistently exhibited lower HPI values throughout the three studied seasons. Further, Canonical Correspondence Analysis identified that pH, TDS, TA, NO3, Na, and NH4 are the key physicochemical parameters which affect the spatiotemporal distribution of cyanobacteria in the studied river system. Overall, this study will offer significant information for hydrologists, ecologists, and taxonomists to develop future holistic strategies for further monitoring of the Sutlej River and other similar habitats.

In the current paper, the effect of lanthanide metal cation substitution on structural, magnetic, optical and transport properties of R0.5Sr0.5Fe0.5Cr0.5O3 (R--La, Nd and Sm) perovskite oxides have been investigated. Structural investigations reveal that there is a phase transition from cubic to orthorhombic symmetry with the doping of heavier rare earth ion. The findings of XPS studies point to the existence of mixed valence states of Cr and Fe ions. The change in magnetization in response to an external magnetic field reveals that the phases have a mostly antiferromagnetic character with some trace amounts of ferromagnetic components. In temperature dependent magnetization studies, magnetic reversal has been observed in Nd doped sample, while La and Sm doped samples only show positive magnetization. The band gap energies of the synthesized materials determined from the UV-vis reflectance spectroscopy lie in the range of 1.60-1.78 eV indicating the semi-conducting nature of the samples. The temperature-dependent resistivity measurements show semi-conducting behaviour of the samples with decreasing temperature which finally become insulating at low temperature. It has been shown that the VRH model provides the best fit for the resistivity data when compared to the other transport mechanism models that were used to describe the electrical conduction process of synthesized phases.

In this study, we investigate the effects of coprocessing algae biocrude with petroleum in hydrotreating units. Algae biocrudes are characterized by being rich in oxygen and nitrogen components, which may pose challenges for refinery catalysts and operations. The studied biocrude was produced from a marine eustigmatophyte microalga in a hydrothermal liquefaction pilot plant and afterward it was distilled to remove excess water and high-boiling material. Coprocessing experiments were carried out in a continuous hydroprocessing pilot plant using vacuum gas oil (VGO) as the petroleum feed. The tests sought to examine different coprocessing ratios (2.5, 5, and 10 vol % biocrude in VGO) relative to baseline operation with pure VGO, as well as to determine the optimum temperature to achieve certain levels of sulfur (<300 wppm) and nitrogen (<100 wppm) removal for a given feed blend. There was a gradual decline in desulfurization activity relative to the baseline level as the coprocessing ratio increased. This unwanted effect was countered by raising reactor temperature between 2 and 6 degrees C over the 380 degrees C baseline temperature for pure VGO. Denitrogenation of the biocrude blends was achieved with ease, indicating that the nitrogen components in the biocrude distillate were mostly nonrefractory. There was no evidence to suggest that coprocessing the biocrude blends accelerated catalyst deactivation. Hydrogen consumption grew to some extent, particularly at the highest coprocessing ratio. The coprocessed products were in general less dense, had higher hydrogen content, and were richer in n-paraffins compared to the one from VGO. Biogenic carbon was found to be preserved in the liquid products at coprocessing ratios of 5% and below, whereas at a 10% ratio apparently, there were losses to gas products.

To investigate the role of PbO as a former or a modifier and effect of its compositional variation on the physical, structural and optical properties, lithium lead borophosphate glasses were synthesized by melt quenching technique. For the physical properties of the prepared glasses, density was measured using the Archimedes principle, which showed an increasing trend from 3.13 to 4.51 with increasing concentrations of lead oxide. Additionally, other physical parameters were calculated based on the measured density values. The structural analysis were performed through X-ray diffraction and Fourier transform infrared spectroscopy. Lack of sharp and characteristic peaks in the XRD spectra confirmed the non crystalline nature of the prepared glasses. Structural units due to PbO, P2O5 and B2O3 were identified from the FTIR spectra. Ultraviolet-visible absorption spectroscopy was performed for optical properties and increase in the indirect band gap from 4.80 eV to 4.90 eV was observed. One glass sample was chosen for doping of erbium, neodymium, thulium and ytterbium, for study of their up-conversion properties. The UV-Vis-NIR absorption spectra of erbium, neodymium, and thulium samples were recorded, and wavelength of 980 nm was chosen for excitation. Ytterbium, acting as a sensitizer, facilitated the conversion of the excitation infrared light into visible light. Upon excitation at 980 nm, the erbium-doped sample emitted light at 520 nm, 547 nm, and 665 nm, utilizing excited state up-conversion (ESA) and energy transfer up-conversion (ETU) mechanisms. Similarly, the neodymium-doped sample emitted at 542 nm, 602 nm, and 660 nm, while the thulium-doped sample emitted at 488 nm, 521 nm, and 649 nm. The results of up-conversion indicate that rare earth-doped lithium lead borophosphate glasses are excellent hosts for up-conversion processes.