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[Display omitted] • Hot-rolled Mg-3Al-0.5Ce alloy possesses anisotropic elastic–plastic fracture toughness (J IC) behavior. • Anisotropic J IC could be attributed to long-aligned Al 11 Ce 3 precipitates within elongated grain boundaries along RD. • Profuse 10 1 ¯ 2 〈 10 1 ¯ 1 〉 extension twins (ET) with lamellae almost ⊥ to RD forms irrespective of the notch, a n ‖ to RD or TD. • The ET lamellae ⊥ and ‖ to crack path lead to trans and inter lamellar crack for a n ‖ to RD and TD , respectively. • Trans-lamellar crack causes larger plasticity in a n ‖ R D and have higher J IC than in a n ‖ T D with inter-lamellar crack. Anisotropic fracture toughness (FT) in a hot-rolled Mg-3Al-0.5Ce magnesium alloy has been investigated using fatigue pre-cracked compact tension (CT) specimens with the notch (a n) ‖ to the rolling direction (R D) and transverse direction (T D). During testing, notable non-linear load–displacement behavior before peak load indicated significant crack tip plasticity. Thus, elastic–plastic FT (J IC) was evaluated and found to be 20.7 N / m m and 15.8 N / m m for a n ‖ to R D and T D , respectively. Long-aligned Al 11 Ce 3 precipitates were present in this alloy within the elongated grain boundaries along RD. During FT testing, profuse 10 1 ¯ 2 〈 10 1 ¯ 1 〉 extension twins (ET) with c-axis almost ‖ and lamellae morphology almost ⊥ to RD formed between these elongated precipitates, irrespective of the notch, a n ‖ to RD or TD. The ET lamellae ⊥ and ∥ to crack path lead to trans and inter lamellar crack for a n ‖ to RD and TD, respectively. Translamellar crack in a n ‖ to R D leads to comparatively high strain hardening, dislocation density, geometrically necessary boundaries, and grain refinement, indicating larger plastic energy dissipation and thereby has higher J IC than in a n ‖ to TD with interlamellar crack. [ABSTRACT FROM AUTHOR]

[Display omitted] • CaO 2 -metallic NP was applied for pretreatment and H 2 production from RS. • MnO 2 -CaO 2 NP addition was beneficial for biomass pretreatment and H 2 production. • MnO 2 -CaO 2 NP addition attained 16% lignin removal than hydrothermal treated RS. • MnO 2 -CaO 2 NP supplementation modulating the acetate and butyrate mediated pathway. In this study, calcium peroxide was modified and doped with metal-based nanoparticles (NP) to enhance the efficiency of pretreatment and biohydrogen generation from RS. The findings revealed that the addition of MnO 2 -CaO 2 NPs (at a dosage of 0.02 g/g TS of RS) had a synergistic effect on the breakdown of biomass and the production of biohydrogen. This enhancement resulted in a maximum hydrogen yield (HY) of 58 mL/g TS, accompanied by increased concentrations of acetic acid (2117 mg/L) and butyric acid (1325 mg/L). In contrast, RS that underwent pretreatment without the use of chemicals or NP exhibited a lower HY of 28 mL/g TS, along with the lowest concentrations of acetic acid (1062 mg/L) and butyric acid (697 mg/L). The outcome showed that supplementation of NP stimulated the pretreatment of RS and improved the formation of acetic and butyric acid through the regulation of metabolic pathways during acidogenic fermentation. [ABSTRACT FROM AUTHOR]

• An efficient biohybrid system developed for oxygenation of n-alkanes. • Synergistic combination of MoS 2 -CNT-Eosin-Y with yeast Candida tropicalis shows higher efficiency. • The biohybrid system enables the efficient regeneration of nicotinamide cofactors. • MoS 2 -CNT-Eosin-Y activates the P450 catalytic cycle resulting higher α, ω dicarboxylic acids yield. To date, oxyfunctionalization of saturated hydrocarbons in a selective fashion is a prime challenge in industry. Currently, Inorganic-biohybrid catalysts have shown tremendous potential for sustainable conversion of fine chemicals by integrating light harvesting potential of inorganic materials with metabolic activity of microbes. Herein, we have developed a biohybrid system combining a highly efficient light-harvesting inorganic material MoS 2 -CNT-Eosin-Y and yeast Candida tropicalis (C.tropicalis) for efficient preparation of α, ω- dicarboxylic acid (α, ω-DCA) using saturated n-alkanes. The yeast C.tropicalis harvests photo generated electrons from the illuminated MoS 2 -CNT-Eosin-Y and uses them for the activation of the P450 catalytic cycle. This process enables the efficient regeneration of nicotinamide cofactors (NADH/NAD+) facilitating production of α, ω-DCA. Under irradiation condition the biohybrid catalyst shows 4.01 times higher dodecanedioic acid production compared to that of native yeast strain. Analysis of NADH/NAD+ ratio and alcohol dehydrogenases (ADH) activity clearly indicates that light illumination on MoS 2 -CNT-Eosin-Y/ C.tropicalis promotes regeneration of cofactor during cellular metabolism of C. tropicalis thereby improving the activity of ADH enzyme resulting higher production of α, ω-DCA. The present work opens up a new avenue for the sustainable synthesis of fine chemicals through tailoring of complex biohybrid pathways. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Lactobacillus lactis has been employed for biohydrogen production. • NiO/Fe 2 O 3 addition stimulates hydrogen production over 18% than control. • NiO/Fe 2 O 3 supplementation redirects butyrate mediated hydrogen metabolism. • Dehydrogenase activity enhances after nano-materials supplementation. • NAD+/NADH and FAD+/FADH 2 pool increases by 19% and 17%. The positive interaction between Clostridium sp. and lactic acid-producing bacteria (Lactobacillus sp) is commonly seen in various high-rate hydrogen production systems. However, the exact role of the hydrogen production ability of Lactobacillus sp in a dark fermentation production system is rarely studied. Lactobacillus delbrueckii was herein used for the first time, to the best of the author's knowledge, to demonstrate biohydrogen production under anaerobic conditions. At first, the pH condition was optimized, followed by the addition of nanoparticles for enhanced biohydrogen production. Under optimized conditions of pH 6.5, substrate concentration 10 g/L, and 100 mg/L of NiO/Fe 2 O 3 , the maximum hydrogen yield (HY) of 1.94 mol/mol hexose was obtained, which is 18 % more than the control. The enhanced H 2 production upon the addition of nanoparticles is supported via the external electron transfer (EET) mechanism, which regulates the metabolic pathway regulation with increased production of acetate and butyrate and reduced formation of lactate. [ABSTRACT FROM AUTHOR]

• Aims to reduce the size of radiators in fuel cell electric vehicles. • Uses phase change materials to compensate for the reduced radiator area. • A generic methodology is proposed for sizing the new thermal management system. • Minimum radiator area requirements for commercial fuel cell vehicles are evaluated. The escalating transport demand over the past decade has intensified the need to replace internal combustion (IC) engines with better alternatives like fuel cells that can simultaneously provide superior performance and diminished emissions. The radiators that are used in fuel cell-based electric vehicles are at least twice the size of IC engine radiators. This leads to vehicle overloading and an increase in fuel consumption. The undertaken study proposes a reduction in radiator size by storing thermal energy in phase change materials. This paper presents a generalized sizing method for the recommended thermal management system, using a simple mathematical approach based on Pinch Analysis. The optimization studies show the possibility to bring down the minimum radiator area requirement in a fuel cell vehicle like the 2022 Toyota Mirai by 5.5 times by using around 13 kg of Paraffin Wax along with it. The proposed methodology is realized by analyzing a few representative parameters like ambient temperature, drag area and curb weight of the vehicle, maximum allowable temperature rise in fuel cells, etc. In addition, the study also estimates the minimum required radiator areas for a few commercial fuel cell vehicles in the Indian environment. [ABSTRACT FROM AUTHOR]

• Novel biohybrid system for solar assisted CO 2 conversion to chemicals. • Synergistic combination of MOF@ TiO 2 with electroactive microbial system shows higher CO 2 conversion. • Efficient electron transfer stimulate Wood-Ljungdahl pathway of electro active microbes. • Well-organized charge transfer from ZTC@TiO 2 to a microbe resulted a high methanol yield. Recently, photosynthetic biohybrid systems are emerged as efficient catalytic materials having advantages of the light-harvesting ability of semiconductors and the catalytic efficiency of biological system. In this context, a stable visible light active Zn-metal organic framework (ZTC) functionalized with TiO 2 (ZTC@TiO 2) was synthesized, and synergistically integrated with an electroactive microbial (EAB) system for efficient CO 2 reduction under visible-light illumination. The resultant bio-hybrid shows remarkably higher CO 2 reduction under visible light irradiation as compared to independent ZTC@TiO 2 and microbe system. Under optimized condition, the bioinorganic hybrid (EAB-ZTC@TiO 2) shows a CO 2 conversion to acetic acid and methanol with a higher selectivity towards methanol. The improved photocatalytic CO 2 conversion and selectivity towards methanol is ascribed to a well-organized donor-acceptor interfacial charge transfer from ZTC@TiO 2 to a microbe, which effectively activates the Wood-Ljungdahl pathway of microbes, thereby improving the CO 2 reduction efficiency. [Display omitted] [ABSTRACT FROM AUTHOR]

Microsatellites are nonrandom hypervariable iterations of one to six nucleotides, existing across the coding as well as noncoding regions of virtually all known genomes, arising primarily due to polymerase slippage and unequal crossing over during replication events. Two or more perfect microsatellites located in close proximity form compound microsatellites. We studied the distribution of compound microsatellites in 118 ssDNA virus genomes belonging to three economically important virus families, namely Anelloviridae, Circoviridae, and Parvoviridae, known to predominantly infect livestock and humans. Among these virus families, 0–58.49% of perfect microsatellites were involved in the formation of compound microsatellites, the majority being located in the coding regions. No clear relationship existed between the genomic features (genome size and GC%) and compound microsatellite characteristics (relative abundance and relative density). The majority of the compound microsatellites resulted from di-SSR couples. A strong positive relationship was observed between the maximum distance value and length of compound microsatellite, percentage of microsatellites involved in the compound microsatellite formation, and relative microsatellite density. The degree of variability among microsatellite characteristics studied was largely a species-specific phenomenon. A major proportion of compound microsatellites was represented by similar motif combinations. The findings of the present study will help in better understanding of the structural, functional, and evolutionary role of compound microsatellites prevailing in the smaller genomes. • Study reports distribution of compound microsatellites in 118 ssDNA virus genomes of Anelloviridae, Circoviridae, and Parvoviridae. • Majority of compound microsatellites are located in the coding regions of the genome. • No clear relationship existed between the genomic features and compound microsatellite characteristics. • Majority of the compound microsatellites resulted from di-SSR couples. • The degree of variability is largely a species-specific phenomenon. [ABSTRACT FROM AUTHOR]

The O 2 /H 2 O couple-based transformation between renewable energy and electricity has emerged as a key step in implementing a carbon-neutral energy infrastructure. Therefore, an inexpensive and efficient electrocatalyst driving both O 2 reduction and O 2 evolution reaction in water becomes critical that can be directly applied in a unitized regenerative fuel cell in both electrolyzer or fuel cell mode. Here, we have crafted a high entropy metal oxide (HEO) containing readily abundant first-row transition metals (Fe, Cr, Co, Mn, Ni) via a metal-organic framework intermediate followed by regulated annealing at 750 °C. This material exhibited bidirectional ORR and OER activity in alkaline aqueous media (pH 14.0) with excellent energy efficiency on either side, showcasing a difference of 0.79 V (while achieving 10 mA cm−2 current density) and ∼90% Faradaic efficiency. The in-depth electrochemical and surface analysis pointed out the key formation of the Ni–OOH layer on the HEO particle and the optimal porosity for maximized electrochemical surface area generation as pivotal factors behind its superior reactivity. An alkaline electrolyzer was assembled with this HEO (anode) and Ni-foam (cathode), which demonstrated concurrent production of O 2 and H 2 over 6 h with minimal alterations in the anodic material. Therefore, this robust, inexpensive, and scalable HEO material can boost the progress in developing sustainable electrolyzer/fuel cell assemblies. • Rational design strategy: An MOF intermediate has been deployed to generate a high entropy metal oxide containing Fe, Cr, Co, Mn, and Ni. • Bidirectional OER/ORR electrocatalysis: This quinary HEO exhibited exceptional OER/ORR activity in alkaline aqueous media (pH 14.0) comparable to Pt/C and IrO 2. • Unraveling the structure-function relationship: The in-depth analysis indicated the key formation of the Ni-OOH layer during this bidirectional electrocatalysis. • Ready for practical applications: An alkaline operational electrolyzer was devised with this HEO (anode) and Ni-foam (cathode) for durable water electrolysis. [ABSTRACT FROM AUTHOR]

The 3-D matrix scale ion-exchange mechanism was explored for high-capacity cadmium (Cd) removal using bone chars (BC) chunks (1–2 mm) made at 500 °C (500BC) and 700 °C (700BC) in aqueous solutions. The Cd incorporation into the carbonated hydroxyapatite (CHAp) mineral of BC was examined using a set of synchrotron-based techniques. The Cd removal from solution and incorporation into mineral lattice were higher in 500BC than 700BC, and the diffusion depth was modulated by the initial Cd concentration and charring temperature. A higher carbonate level of BC, more pre-leached Ca sites, and external phosphorus input enhanced Cd removal. The 500BC showed a higher CO 3 2-/PO 4 3- ratio and specific surface area (SSA) than the 700BC, providing more vacant sites by dissolution of Ca2+. In situ observations revealed the refilling of sub-micron pore space in the mineral matrix because of Cd incorporation.The X-ray nanodiffraction (XND) analyses revealed that Cd was mainly removed from water by incorporation into the mineral lattice of 500BC via ion exchange, rather than surface sorption and precipitation, and the mineral phase was transformed from hydroxyapatite (HAp) to cadmium hydroxyapatite (Cd-HAp). The Rietveld's refinement of X-ray diffraction (XRD) data resolved up to 91% of the crystal displacement of Ca2+ by Cd2+. The specific phase and stoichiometry of the new Cd-HAp mineral was dependent on the level of ion exchange. This mechanistic study confirmed that 3-D ion exchange was the most important path for heavy metal removal from aqueous solution and immobilization in BC mineral matrix, and put forward a novel and sustainable remediation strategy for Cd removal in wastewater and soil clean-up. [Display omitted] • Bone char at 500 °C integrated more Cd into the mineral matrix than at 700 °C. • Depth-dependent spatial distribution of Cd-HAp occurred to the bone char. • Matrix scale ion exchange drives Cd removal than complexation and precipitation. • A higher CO 3 2−/PO 4 3− ratio of 500 °C bone char led to higher removal of Cd. • Pre-leached bone char, and external phosphorus input enhanced Cd removal. [ABSTRACT FROM AUTHOR]

The environmental issues existing all over the world have pushed the researchers to innovate products that would lead to the reduction of all sorts of pollution. This study focused on the utilization of underutilized Agave Americana fibres in yarn form after converting them into braids. An attempt has been made to modify the surface of the fibers using enzyme and alkali for improvising the uptake and adherence of resin which enhances the properties of composites. The spun Agave Americana fibres were procured and treated chemically and biologically for removing the fibre chemical constituents and natural oils that cover the outer layer of the fiber cell wall. The fibres from the yarn showed the improvement in morphological analysis after treatments which have increased the fiber-matrix adhesion leading to the improved mechanical properties of the composites. Both the treated yarns were braided for reinforcements to provide unique structural features and characteristics to the composites. The matrix used was epoxy resin because of its superior qualities and high performance. The roughness of the composite structure reinforced with the chemical treated yarn braid reinforced samples was the highest with 27.60 over the untreated and enzyme treated samples. The tensile strength of alkaline treated yarn braid reinforced composites increased with 48.56% over the untreated yarn braid reinforced composites whereas the enzyme treated yarn braid reinforced composites exhibited only 37.89% increase over the untreated sample. As for the flexural strength, the results were in contrast with the tensile strength results as the enzyme treated yarn braid reinforced composites showed more increase with 42.16% whereas it was only 34.33% in the alkali treated yarn braid reinforced composites. At higher temperatures the thermal stability was noted to be the highest in the alkali treated sample with 92.5%. These results have shown that these treatments and braided structure can be used as reinforcement for bringing good performance composite structures. • This study focused on the utilization of underutilized Agave Americana fibres in yarn form after converting them into braids. • To modify the surface of the fibers using enzyme and alkali. • Braided structure can be used as reinforcement for bringing good performance composite structures. [ABSTRACT FROM AUTHOR]

Stroke has become one of the leading causes of lower limb paresis. Costing the patients, a fortune for its diagnosis and prognosis. Clinical experimentations have proven that one can regain ambulation if the rehabilitation is started in the acute or sub-acute stage. Traditional mode of rehabilitation include manual therapies which are labor-intensive and time consuming. Therefore, robotic training are preferred over manual therapies. Nevertheless, there are some limitations such as devices are bulky and complex, some are not portable, others need body weight support system, and costly. To address such issues, this paper proposes development of a new Caster Walker Gait Trainer (CGT) for gait rehabilitation. CGT is an end-effector based passive device in which Stephenson III six-bar linkage has been implemented to mimic the kinematics of a healthy gait. The trainer device uses a belt-pulley system for providing motion to the linkage. The lower limb of the patient gets the drive as he/she pushes the cater walker forward or backward. The paper also proposed the optimal design of defect-free Stephenson III six-bar linkage using loop-by-loop approach. To design the linkage, an optimal problem is formulated, and tear drop ankle trajectory is desired. The optimization problem is solved using a nature-inspired algorithm and it is found that the trajectory generated by the synthesized mechanism is able to mimic the desired trajectory. Then using the notion of inverse kinematics, hip and knee trajectories are obtained from the generated ankle trajectory for validation. • Stephenson III six-bar linkage embedded caster walker. • The patient specific mechanism to operate pedal when they push the caster walker rectilinearly. • Belt pulley driven Caster Walker Gait Trainer (CGT). • Control algorithm for automating the rehabilitation and training program of the patient. • Adaptability and acclimatization of different patients with faster results of rehabilitation. [ABSTRACT FROM AUTHOR]

Due to high-speed operation at low inertia, flexible manipulators are becoming more and more popular in today's world. These manipulators produce excessive vibration, which must be reduced using an efficient control technique for the manipulator to function well. In the present study, a flexible manipulator model with a single link is built in such a manner that it can be considered as a flexible fishing rod. The free end of the flexible rod has a provision for applying a payload, which serves to give a deflection of the flexible rod. A lumped parameter method is adopted for modelling the flexible rod as well as the string using the Sim-Mechanics tool in MATLAB. Simulations were carried out for sudden and sinusoidal loading. It has been found that the flexible link produces excessive vibration under both sudden and sinusoidal loading. A proportional integral derivative (PID) controller is used to suppress the excessive vibration generated in the simulation model. Four different locations (Location 1: 15 cm; Location 2: 30 cm; Location 3: 45 cm; and Location 4: 60 cm) are selected for controller positioning. Simulation revealed that the minimum deflection was observed at location 4, i.e., at the tip for both sudden and sinusoidal loading. The developed model is validated using two loading conditions, viz., the beam's self-weight and a point load of 30 N at the free end. It has been found that the simulation results resemble the analytical results with an error of 0.44% and 0.36% for both the loading conditions. • A model of fishing rod-type flexible robotic manipulator is developed. • Model is developed based on Lumped parameter using Sim-Mechanics. • Sudden loading and sinusoidal loading are applied at the free end. • PID controller is used to suppress the excessive vibration generated in the simulation model. [ABSTRACT FROM AUTHOR]

A theoretical approach using first-principle calculations of the density of states (DOS) of functionalized carbon nanotubes (CNTs) is carried out to understand their enhanced electron field emission (FE) properties. The theoretical functionalization of CNTs is perceived using hydrogenation (H/O–H) and oxidation methods. In order to investigate the enhancement in the FE properties of functionalized CNTs, both single-walled carbon nanotubes (SWCNT) and double-walled carbon nanotubes (DWCNT) are studied. The work function is observed to be more decreased in case of zigzag SWCNT (φ = 3.32 for oxygenated SWCNT) as compared to others SWCNT. The dependence of DOS on zigzag/armchair edge functionalization has also been investigated to reveal the impact of DOS on FE. The observed results indicate that edge functionalization of CNTs leads to significant changes in the band structure, DOS, and work functions. The shifting of DOS away from the Fermi level and decrease in work function is evidenced owing to the reduction in the curvature effect of CNT. Also, due to enhanced DOS near the Fermi level, making them a better proposition for FE applications. Our calculations provide an in-depth insight into the functionalization mechanism to understand the enhanced FE properties from them. • Vienna ab initio simulations package is utilized to perform simulations for carbon nanotubes (CNTs). • Functionalization of CNTs via hydrogenation and oxidation has been studied. • Impact of CNTs fuctionalization on field emission has been studied and explained using density of states (DOS). • Edge functionalization of CNTs leads to substantial changes in the band structure, DOS, and work functions. [ABSTRACT FROM AUTHOR]

DFT/TD-DFT methods were used to determine the fluoride anion sensing mechanism of 3′,6′-Bis(tert-butyldimethylsilyloxy)spiro[benzo[f]chromene3,9′ffuorene], abbreviated as SP. The description of ring opening in the ground state of SP molecule and its isomerization in open form is presented. It was revealed from the study that in the ground state, SP is the most stable form in contrast with the isomer obtained in the open form. To initiate the ring opening, at first, the fluoride ion attacks as a nucleophile to de-silylate the SP molecule. This attack of fluoride ion may induce Cspiro-O bond cleavage leading to the formation of two anionic species, i.e., MC-D1 and MC-D2 respectively (MC is merocyanin). The mono-de-silylation process was endogenic, which was followed by the ring opening process. Furthermore, the orthogonal geometry of probe SP does not show ICT character, whereas, MC-D1 and MC-D2 displayed ICT character owing to the formation of planar geometry along with an increase in conjugation. The fluorescence property of SP, and most stable isomers of open form (CT, MC-D1, and MC-D2) were predicted theoretically. The calculated emission spectra uncovered that SP may show fluorescence, which could be quenched in presence of fluoride anion. [Display omitted] • SP molecule is thermodynamically more stable in comparison to open form isomers in the ground state. • Addition of the F- anion triggers the endogenic de-silylation process in SP, which is followed by the ring-opening process. • The mono and di-desilylated anionic open forms of SP show ICT character. • SP molecule may undergo the ring-opening process in theS 1 state. • The SP and CT may exhibit fluorescence. [ABSTRACT FROM AUTHOR]