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Over the years, alloys have been the predominant choice of electrode material for electrochemical hydrogen storage. However, they encounter challenges emerging from their complex synthesis process and intricate structure, leading to low discharge capacity. Hierarchical Ni 3 S 2 nanorods-embedded flower-shaped NiMn-layered double hydroxide (LDH) microspheres (∼10 μm) are, thus, synthesized via a facile one-pot binder-free hydrothermal process and examined for their electrochemical hydrogen storage behavior. The Ni 3 S 2 /Ni 2 Mn 1 -LDH composite showcased superior reversibility and a maximum storage capacity of ∼860 mAh/g at 1000 mA/g current density under ambient temperature and pressure conditions. It exhibited a Coulombic efficiency of ∼86% and a capacity retention rate of ∼98% even after 100 charge-discharge cycles in 3 M KOH electrolyte. The enhanced electrochemical performance is attributed to the layered morphology and synergistic behavior demonstrated by the Ni 3 S 2 nanorods on the LDH layers. To this end, the material emerges as a promising and efficient candidate to be utilized in energy storage systems. [Display omitted] • Ni 3 S 2 /Ni 2 Mn 1 -LDH developed as an efficient material for electrochemical H 2 storage. • High storage capacity of ∼860 mAh/g attributed to Ni 3 S 2 -embedded LDH microspheres. • High cyclic stability over 100 cycles with a Coulombic efficiency of ∼86%. • Storage mechanism depicting synergistic effects of spillover, redox, and H-bonding. [ABSTRACT FROM AUTHOR]

In this work, heterogeneous functionally graded material (FGM) with SS316LSi and ER70S-6 is deposited using twin wire arc additive manufacturing technique. Tribological, mechanical and microstructural characterization were undertaken for the developed FGM structure. Microstructural analysis revealed acicular ferrite and bainite regions near molten pool boundaries, with "lathy ferrite" formations during solidification. Developed FGM structure exhibited appreciable mechanical strength with an average yield strength of 440±6 MPa, ultimate tensile strength of 714±13 MPa, and 43%±1.23 elongation. Worn surfaces revealed an adhesive wear mechanism. Gradation in wear rate and average coefficient of friction, measured as 9.98 × 10−4 mm 3/N-m and 0.46–0.51, respectively, was observed in the final deposited structure with intermediate values between SS316LSi and ER70S-6. Results reveal that as-deposited FGM exhibits superior wear resistance and mechanical performance compared to SS316LSi and ER70S-6. [Display omitted] [ABSTRACT FROM AUTHOR]

A hierarchical porous structured carbon micro-nanofiber containing the bimetallic configuration of the nickel (Ni) and ceria (CeO 2) nanoparticles (NPs) was synthesized and tested for the electrochemical hydrogen (H 2) storage capacity. The electrode exhibited a high H 2 storage capacity of 498 mA h/g or 1.858% (w/w) at the charge-discharge current density of 500 mA/g. A mechanistic insight showcased the combined contributions of the high surface area containing activated carbon microfiber (ACF) substrate, the graphitic carbon nanofibers (CNFs), and the Ni and CeO 2 NPs, towards the augmented electrochemical H 2 storage capacity and cyclic stability of the fabricated Ni–CeO 2 –CNF/ACF electrode. Ni served as the catalyst for growing the CNFs via chemical vapor deposition as well as for storing H 2 via spillover mechanism, while CeO 2 created the charge carrier vacancies in the material. The measured cycle retention capacity of 99% and charge-discharge efficiency of 97.6% confirm the electrochemically stable characteristics of Ni–CeO 2 –CNF/ACF, and clearly indicate it to be an economically viable and efficient H 2 -storage material. Image 1 • Ni-CeO 2 -CNF/ACF developed as an efficient electrode for electrochemical H 2 storage. • High H 2 storage attributed to the combined roles of Ni and CeO 2 , CNFs and ACFs. • High cyclic stability and charge-discharge efficiency of the fabricated electrode. [ABSTRACT FROM AUTHOR]

• Co-production of pectinase, cellulase, and xylanase from Bacillus subtilis ABDR01. • Ultrasound facilitated process intensification of microbial enzyme production. • Ultrasonic irradiation enhanced cell biomass concentration and enzyme production. • Ultrasound treatment improved enzyme co-production by 38.15 %, 53.77 %, and 24.59 %. The effect of low-intensity ultrasound irradiation was studied to improve the co-production for pectinase, cellulase, and xylanase enzymes using Bacillus subtilis ABDR01. Different parameters such as ultrasonic irradiation at the different growth phases of the bacterial strain, ultrasound power, irradiation duration, and irradiation duty cycle were assessed. Sonication with 90 W ultrasound power, 25 kHz frequency with 70 % duty cycle for 5 min at 6 h of bacterial growth phase gave the maximum productions of 87.82 U/ mL pectinase 22.17 U/ mL cellulase and 137.95 U/ mL xylanase respectively. The enzyme activity of pectinase, cellulase, and xylanase was enhanced by about 38.15 %, 53.77 %, and 24.59 %, respectively, compared to non-sonicated control cultivation. This optimized low-frequency ultrasound irradiation to bacterial cells enhanced the nutrient uptake rate and increased the cell wall permeability, which results in higher enzyme productivity. Our results signify the effectiveness of low-frequency ultrasound irradiation for improved enzyme yields and hyperactivation during microbial fermentation. [ABSTRACT FROM AUTHOR]

Abstract A nickel (Ni)-graphene oxide (GO) dispersed carbon film was prepared by the carbonization of the phenolic precursor-based polymer. Three dimensional (3D) micropillars were fabricated on the carbon film using laser ablation technique. The micropillars-engraved film was used as electrodes in a single chamber microbial electrolytic cell (MEC) for hydrogen (H 2) production. Besides promoting biofilm formation at anode, the 3D micropillars provided relatively more exposure to the in situ dispersed electrocatalytic Ni nanoparticles (NPs) and electroconductive GO in the carbon film. The Tafel slope of ∼49 mV dec−1 indicated that Heyrovsky reaction or electrochemical desorption was the rate determining step for H 2 evolution. A H 2 production rate of 4.22 ± 0.21 m3m−3d−1 was measured at 0.8 V in the prepared electrode-based MEC. Whereas the overall H 2 and cathodic recoveries were measured to be 92.3 ± 2.77% and 98.7 ± 0.99%, respectively, the Coulombic and overall energy efficiencies were determined to be 93.5 ± 2.81% and 72.2 ± 3.61%, respectively. The relatively higher efficiency of the MEC was ascribed to the synergistic contributions of the 3D micropillars, Ni NPs and GO, indicating the prepared electrode to be a viable alternative to the expensive noble metal-based electrodes used in MECs for H 2 production. Graphical abstract Image 1 Highlights • Ni-rGO dispersed 3D micropillars fabricated on carbon film by laser ablation. • 3D micropillars-engraved carbon film used as an efficient electrode for MEC. • High H 2 evolution rate attributed to synergistic roles of 3D structure, Ni and rGO. • 3D micropillars facilitated biofilm formation at anode. [ABSTRACT FROM AUTHOR]

A novel one step method was developed to dope nitrogen (N), sulfur (S) and carbon (C) in the Fe nanoparticles-dispersed carbon nanofibers (CNFs) grown over carbide-derived carbon (CDC), using thiourea as the single source of N, S and C. The synthesized N/S-Fe-CNF/CDC electrode was successfully used in a microbial fuel cell (MFC). When tested as the oxygen reduction reaction (ORR) catalyst, the electrode achieved a high current density (2.261 ± 0.002 mA/cm2), high OCP (0.611 ± 0.005 V), high stability upto 400 cycles, response time of ∼11 s, electron transfer number in the range 3.73–4.03, and Tafel slopes of −0.0627 and −0.183 V/dec at low and high current densities, respectively. A first order kinetics and a 4e− pathway were deduced from the ORR analysis. Notably, the fabricated MFC based on the prepared electrode produced a high current density of 1.3887 ± 0.002 mA/cm2, high OCP of 0.626 ± 0.005 V and maximum power density of 0.238 ± 0.002 mW/cm2, attributed to the synergistic effects of heteroatoms, Fe nanoparticles, and CNFs. Image 1 • Thiourea was used as the single source of heteroatoms (N, S) and carbon in Fe-CDC. • N/S-Fe-CNF/CDC-based MFC generated high OCP and power density. • Synergy of N, S, Fe, and graphitic CNFs resulted in the high performance of MFC. [ABSTRACT FROM AUTHOR]

Nickel (Ni) and ceria (CeO 2 ) nanoparticles (NPs) containing microporous and graphitic carbon nanofiber (CNF)-activated carbon microfiber (ACF)-based adsorbent was prepared as an efficient hydrogen (H 2 ) storage material at 200 °C and 1 bar. The prepared Ni CeO 2 -ACF/CNF was tested for the H 2 storage capacity under batch (static) as well as dynamic (flow) conditions, and the amounts of H 2 adsorbed were measured to be approximately the same. In its multiple roles, Ni NP served as the chemical vapor deposition catalyst to grow the CNFs on ACF, besides enhancing H 2 adsorption via the spillover mechanism, and decreasing the reduction temperature of CeO 2 . The experimental data corroborated the positive effects of the synergistic interaction between the Ni and CeO 2 NPs and the graphitic characteristics of the CNFs on H 2 adsorption. Although CeO 2 induced irreversibility in H 2 adsorption on Ni CeO 2 -ACF/CNF, the adsorbent was completely regenerated at 300 °C and 1 bar, indicating the developed H 2 storage-regeneration process in this study to be effective, practical, and energy efficient. [ABSTRACT FROM AUTHOR]

Nickel (Ni) metal-containing microporous and graphitic carbon nanofiber (CNF)-based adsorbent was prepared for the first time as a hydrogen (H 2 ) storage material. Ni was in situ dispersed in the activated carbon microfiber (ACF) substrate and it served as the chemical vapor deposition catalyst to grow CNFs on the ACF. The prepared ACF/CNF multi-scale web was modified using steam to increase the BET surface area (S BET ) and microporosity content of the material. The H 2 storage capacity of the materials was determined at different temperatures (77, 273 and 298 K), and under batch (static) and dynamic (flow) conditions. The comparative data revealed that the S BET of the materials controlled the storage capacity at cryogenic temperature. The positive effects of the graphitic CNFs and the inclusion of metal (Ni) in the materials were evident at elevated temperatures (273 and 298 K). The H 2 uptakes under dynamic conditions were determined to be approximately the same as under batch conditions, indicating that the prepared materials can be efficiently used as adsorbents for H 2 under flow conditions. [ABSTRACT FROM AUTHOR]

The emergence and rapid growth of smart and IoT devices increased the demand for an efficient and effective task computing platform. Mobile edge computing (MEC) has emerged as a solution for the execution of these proximal and latency-sensitive tasks. Additionally, security is a concern with any computation platform containing distributed and heterogeneous devices. Blockchain is a recent technique that has emerged as a potential solution to provide authenticity, security, consistency, and integrity. The proposed work utilizes the advantages of blockchain technology to provide security with the scheduling of tasks. BSFW has been proposed for the secure scheduling of tasks that utilizes the features of the fireworks algorithm for the optimization of schedules. The objective function has been presented to optimize the makespan and energy consumption of the schedules. To evaluate the effectiveness of the proposed algorithm, different experiments have been conducted that results in the outperformance of the proposed work with other compared techniques in different scenarios. The result has provided 14–25% improvement in performance compared to other approaches. The evaluation has been performed on makespan, energy consumption, throughput, convergence, and execution time metrics. • A new task scheduling scheme has been proposed that solves the problem of task scheduling in MEC environment. • A security and reliability feature has also been added while scheduling in the MEC environment. • Blockchain technique has been applied to provide security in the network. • Firework algorithm has been applied to provide an optimal solution for task processing. • Extensive performance evaluation has been performed to evaluate the performance of the BSFW. • The evaluation outcome has shown a noticeable improvement in performance metrics against other compared techniques. [ABSTRACT FROM AUTHOR]

Catalytic wet air oxidation (CWAO) is extensively used for the destruction of organic contaminants in wastewater. The present study describes the removal of phenol from water, used as a model organic contaminant, by CWAO with iron (Fe) metal nanoparticles (NPs)-doped carbon microbeads (∼0.6 mm) as the catalyst. The Fe-carbon composite was prepared by the carbonization and activation of the phenolic precursor-based polymeric beads in which the Fe NPs were in-situ added during the polymerization stage. Carbon nanofibers (CNFs) were grown on the carbon microbead substrate by catalytic chemical vapor deposition with acetylene as the carbon source. Oxidation reactions were carried out under different operating conditions in a high pressure-stirred reactor, viz., temperature, catalyst loading, and speed of the stirrer. The reactor was fitted with an especially configured impeller cum catalyst basket which held the prepared CNF-decorated Fe-doped carbon beads. The data showed an efficient remediation of the phenol-laden water, indicating the potential scale-up of the proposed CWAO catalyst and impellor cum catalyst holder-assembly in this study. [ABSTRACT FROM AUTHOR]

Rhein, the most toxic anthraquinone moiety in Cassia occidentalis seeds, has been associated with hepatomyoencephalopathy (HME) in children. Structural and functional alterations in the lymphoid organs have been reported both in HME patients and experimental animals indicating a possibility of the dysfunction of immune system following exposure to CO seeds or its toxic anthraquinones ( Panigrahi et al., 2014a ). In the present study the mechanism of immune response of Rhein in splenocytes has been investigated by measuring functional assays of lymphocyte, cell surface receptor expression and analysis of cytokine levels. Results indicate that Rhein at a maximum dose of 10 μM is non cytotoxic up to 72 h in splenocytes. In addition to its potential to decrease the allogenic response of T-cells, Rhein significantly suppresses the proliferation of the concavalin A (Con A) and lipopolysaccharide (LPS) stimulated splenocytes. Lymphocyte receptor expression analysis revealed that Rhein exposure significantly down regulate the expression of CD3e, CD4, CD8, CD28, CD69 molecules in T-cells. The expression of CD19, CD28, CD40 in B-cells were also found to be significantly decreased following Rhein exposure. In accordance with the functional responses, Rhein treatment significantly lowered the expression of IL2 and IL6 cytokines in Con A stimulated splenocytes, and IL6, IL10, IFNγ and TNFα in LPS stimulated splenocytes. Over all, the study suggests the immunomodulatory activity of Rhein and that it would be useful in understanding the immune response of CO seeds in human subjects. [ABSTRACT FROM AUTHOR]

Sodium benzoate (SB) is a widely used food preservative due to its bacteriostatic and fungistatic properties. The acceptable daily intake of SB is 5 mg/kg-bw, however, it has been found to be used in the food commodities at relatively high levels (2119 mg/kg). Earlier studies on SB have shown its immunosuppressive properties, but comprehensive immunotoxicity data is lacking. Our studies have shown that SB was non cytotoxic in splenocytes up to 1000 μg/ml for 72 h, however at 2500 μg/ml it was found to be cytotoxic. Thus, 1000 μg/ml dose of SB was chosen for the subsequent experiments. SB significantly suppresses the proliferation of Con A and LPS stimulated splenocytes at 72 h, while allogenic response of T cells was significantly decreased after 96 h. SB did not affect the relative expression of CD3e or CD4 molecules following 72 h exposure, however, it downregulated the relative expression of CD8 co-receptor. Further, exposure of splenocytes to SB for 72 h led to reduced expression of CD28 and CD95, which play a vital role in T cell activation. SB also suppresses the relative expression of CD19, CD40 and CD95 receptors on B cells after 72 h. In addition to the functional responses, SB lowered the expression of IL4, IL6, IFNγ and IL17 cytokines in Con A stimulated splenocytes; and IL6, IFNγ and TNFα in LPS stimulated splenocytes following 48 h of exposure. Taken together, the present study is suggestive of the immunomodulatory potential of SB. [ABSTRACT FROM AUTHOR]

Leather industry has significant economic influence; however, it suffers from the negative impact due to environmental pollution caused by tannery wastes produced during leather processing processes. The tanning processes contribute significantly to chemical oxygen demand (COD), total dissolved solids (TDS), chlorides, sulfates and heavy metal pollution. The chemicals discharged into aquatic systems end up in highly polluted sediments and salinisation of rivers. European Chemical Agency (ECHA) has prioritized some of the hazardous chemicals used in leather under Substances of Very High Concern (SVHC) and substances for Authorization. The situation has highlighted the need for greener technologies. Out of the two broad categories of technical methods, the first group involves the introduction of processing technologies by decreasing the effluent pollution load, avoiding the use of harmful chemicals and producing solid wastes that can be used as by-products. The other category is related to the treatment of wastewater, handling and processing of solid waste in an environment-friendly manner. Both methods have been applied to prevent negative impact on the environment during leather production. The methods have been reviewed for their technical suitability and commercial feasibility and it was felt that combination of both is essential. The technologies can have up-front additional costs but have to be balanced against multiple benefits in terms of environmental cleanup, improved labour productivity, material quality consistency and better international image. By using the best available technologies and optimized systems the leather industry can evolve as an environment friendly technology. [ABSTRACT FROM AUTHOR]

The present study was undertaken to investigate the effect of Cassia occidentalis (CO) seeds on the transcriptional expression patterns of mRNAs in rat liver by microarray analysis. The results indicated that exposure of CO (0.5%) seeds in diet to rats differentially regulated 60 transcripts belonging to various metabolic pathways including, oxidative stress, xenobiotic metabolism, carbohydrate metabolism, cell cycle, apoptosis etc. The expression of AKT1, CAT, SOD1, CYP1A1, CYP2B1, TGF-β, BAX, CREB1, JNK1 and IL-6 were validated by the qRT-PCR. In addition, involvement of oxidative stress was observed due to marked depletion of glutathione, increase in lipid peroxidation and modulation of antioxidant enzymes in hepatic tissue of rats treated with 0.5-2.0% CO in diet. Furthermore, significant decrease in the levels of Phase 1 (EROD, MROD and PROD) and Phase 2 (QR and GST) enzymes following 0.5-2.0% CO exposure indicates the impairment of xenobiotic metabolism and possible accumulation of toxic ingredients of the seeds in liver. Overall, the study predicts the involvement of multiple pathways and related biomolecules in CO induced hepatotoxicity and the data may be useful in formulating strategies for therapeutic interventions of suspected CO poisoning study cases. [ABSTRACT FROM AUTHOR]

Abstract: Sunset yellow FCF (SY), a permitted food color, is extensively used in various food preparations and quite often exceeds the permissible levels (100–200mg/kg). Several toxicity studies on SY are reported, however immunomodulatory properties have not been explored yet. To investigate the immunotoxic properties of SY, splenocytes were isolated, cultured and subjected to mitogen stimulated proliferation assay (lipopolysaccharide, LPS or concanavalin A, Con A), mixed lymphocyte reaction (MLR) assay, immunophenotypic analysis of cell surface receptor expression and assay for cytokines release in the culture supernatants were performed in the presence of SY. Since SY did not exhibit any cytotoxicity up to 250μg/ml, this dose was used for further studies. It was observed that SY (250μg/ml) significantly (p <0.05) suppressed the mitogen induced proliferation of splenocytes and MLR response. Further, immunophenotypic analysis revealed that SY alters the relative expression of CD3e/CD4/CD8 in T cells and CD19 in B-cells. Consistent with the suppression of T-cell and B-cell responses and altered surface receptor expression, SY also lowered the expression of IL2, IL4, IL6, IL-17, IFN-γ and TNF-α cytokines. These results suggest that non-cytotoxic dose of SY may have immunomodulatory effects. [Copyright &y& Elsevier]

Abstract: Orange II, an azo dye, is not permitted in food preparations, but high levels of the dye have been detected in different food commodities. Though there are reports on the toxicity of Orange II but knowledge based on the immunomodulatory properties of Orange II is scanty. The present investigation was undertaken to study the in vitro immunotoxic potential of Orange II in splenocytes. Splenocytes were isolated, cultured and subjected to immunophenotypic analysis, mixed lymphocyte reaction (MLR) assay or stimulated with lipopolysaccharide (LPS) or concanavalin A (Con A) for 72h. The supernatant was collected for cytokine assays. Orange II showed cytotoxic effects at 100–1000μg/ml concentrations and 50μg/ml was determined as the highest non-cytotoxic dose. Orange II at the non-cytotoxic dose (50μg/ml) significantly altered the relative distribution of T and B-cells, MLR response and the mitogen induced proliferative response of T-cells and B-cells. Consistent with the hypo-responsiveness of the T and B-lymphocytes, Orange II induced a concomitant decline in the secretion of cytokines IL-2, IL-4, IL-6, IFN-γ, TNF-α and IL-17. On the contrary, there was an increase in the production of IL-10, an anti-inflammatory regulatory cytokine, which may be one of the causative factor for immunosuppressive property of Orange II. These results suggest that non-cytotoxic dose of Orange II may have immunomodulatory effects. [Copyright &y& Elsevier]

Abstract: Incorporation of europium luminescent centre in its chosen valence state Eu2+ or Eu3+ has been effectively done in the complex strontium hexa aluminate SrAl12O19 by high temperature solid state reaction at regulated environment. Nanocrystalline SrAl12O19 doped with europium in its reduced form Eu2+, could be successfully synthesized by controlled autocombustion process from the nitrate salts of precursor components. The charge state of the dopant ion was ascertained from photoluminescence studies which show series of sharp emission lines in 590–710nm range for Eu3+ activator whereas broad green emission for Eu2+ activator. Nanocrystalline SrAl12O19:Eu showed blue shifted broad green emission characteristic of Eu2+ 4f5d transition demonstrating the effectiveness of autocombustion process in producing Eu2+ charge state which usually requires a reducing environment. Intra-band gap excitation of SrAl12O19 between energy levels of rare earth dopant could be tailored effectively to obtain broad excitation transition in near UV/violet region and emission in the visible region. Striking dependence of morphology on valence state of Eu and growth environment was observed which could be explained due to creation of solid state defects in formation of lamellar structure in oxygen-rich environment. [Copyright &y& Elsevier]