Lightweight computing technologies such as the Internet of Things and flexible wearable systems have penetrated our everyday lives exponentially in recent years. Without a question, the running of ...such electronic devices is a major energy problem. Generally, these devices need power within the range of microwatts and operate mostly indoors. Thus, it is appropriate to have a self-sustainable power source, such as the photovoltaic (PV) cell, which can harvest indoor light. Among other PV cells, the dye-sensitized solar cell (DSSC) has immense capacity to satisfy the energy demands of most indoor electronics, making it a very attractive power candidates because of its many benefits such as readily available materials, relatively cheap manufacturing methods, roll-to-roll compatibility, easy processing capabilities on flexible substrates and exceptional diffuse/low-light performance. This review discusses the recent developments in DSSC materials for its indoor applications. Ultimately, the perspective on this topic is presented after summing up the current progress of the research.
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Coal and coal-based products (by-products), along with other fossil fuels should be used with caution because of their impact on human health and the global climate. In the light of the environmental ...impact these fossil fuels cause, it's essential to understand the elemental configuration of coal-derived samples and their impact on the ecosystem. Some reports in past have described, geochemical and mineralogical physiognomies of fly-ash and their impact on the environment. However, a comprehensive investigation of various aspects of fly ash like geochemistry, mineralogy, morphology, and toxicological effects has been very sparse and the present study reports the above aspects. The ICP-OES studies confirm the presence of various elements (Al, Ca, Fe, Mg, Na, P, S, Si, and Ti) in the samples. The XRD analysis exposed the presence of minerals like Quartz, H-Hematite, Anatase, Muscovite, and Rutile, in addition to the various phases such as amorphous and crystalline in the fly-ash. Specific samples also possessed Ilmenite which is uncommon in many other samples. Chromium and lead, the well-known heavy metals to cause soil and water pollution in the neighbourhood were found to be existing in higher concentrations in the fly-ash samples, whereas cadmium was found to be the least among the toxic elements found in the samples. The samples were subjected to FE-SEM analysis, which reveals the presence of irregularly shaped minerals and unburnt carbon known to reduce the burning efficiency of coal, especially in power plants. Toxicology studies reported in the work suggested that fly-ash is toxic to the environment at higher concentrations than at lower concentrations.
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•Coal Fly Ash samples have been characterized for geochemical, mineralogical and toxicological properties.•Environmental impacts of coal fly ash from coal-fired power plants have been reported.•Various elements and their oxides in amorphous and crystalline forms are part of fly ash samples.•Higher concentrations of the heavy metals in fly ash samples appear to be toxic.
For large-scale energy storage, iron-based flow batteries (IRFBs) have been considered as a better choice because of their low-cost and use of environmentally friendly iron-based salts. The ...development of a IRFBs has been limited by the sluggish kinetics of the reaction, especially at the positive electrode during charging. Therefore, it is very important to look for stable electrolytes and superior electrode materials along with their modifications. Carbon-based electrodes are majorly used in IRFBs and these electrodes are feasible to modify using electrocatalysts. In the current study, nitrogen-doped carbon particles (NICaps) derived from Bermuda grass were used to modify graphite felt electrode. SEM, EDAX, Raman, and XPS analysis were used to characterize the modified graphite felt (MGF) electrode. It was observed that the NICaps MGF electrode had a significant improvement in electrochemical properties. The cathodic and anodic peak currents for the MGF electrode (1.55 and 1.63 mA/cm2 respectively) had a remarkable increase in comparison with the untreated graphite felt electrode (UGF) (0.48 and 0.88 mA/cm2 respectively). The Nyquist plot and the data derived from the equivalent circuit indicated lower charge transfer resistance for MGF. The charge-discharge studies carried out using 132 cm2 cell reveals that the modified electrodes result in higher current uptake of 50 mA/cm2 whereas the current uptake from the UGF electrode was limited to 20 mA/cm2. The battery resulted in an average coulombic efficiency of 95%, the peak power density of 60 mW/cm2, and better stability during multiple cycling.
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•NICaps modified graphite felts were used as electrodes for better performance of IRFBs.•CV, EIS and Tafel studies showed significant improvement in electrochemical performance.•Charge-discharge studies reveals the higher current density uptake of 50 mA/cm2.•MGF resulted in the average CE of 95% and the electrode was stable upto 50 charge-discharge cycles.
The bismuth (Bi
)-doped cobalt ferrite nanostructures with dual phase, i.e. cubic spinel with space group Fd3m and perovskite with space group R3c, have been successfully engineered via self-ignited ...sol-gel combustion route. To obtain information about the phase analysis and structural parameters, like lattice constant, Rietveld refinement process is applied. The replacement of divalent Co
by trivalent Bi
cations have been confirmed from energy dispersive analysis of the ferrite samples. The micro-structural evolution of cobalt ferrite powders at room temperature under various Bi
doping levels have been identified from the digital photoimages recorded using scanning electron microscopy. The hyperfine interactions, like isomer shift, quadrupole splitting and magnetic hyperfine fields, and cation distribution are confirmed from the Mossbauer spectra. Saturation magnetization is increased with Bi
-addition up to x = 0.15 and then is decreased when x = 0.2. The coercivity is increased from 1457 to 2277 G with increasing Bi
-doping level. The saturation magnetization, coercivity and remanent ratio for x = 0.15 sample is found to be the highest, indicating the potential of Bi
-doping in enhancing the magnetic properties of cobalt ferrite.
Graphene as a single or few-layered 2D material acts as a stable and efficient substrate to build effective nanocomposite catalysts for numerous applications. In this study, a few layers of ...exfoliated graphene sheets are engineered with novel high entropy alloy (HEA) nanoparticles through mechanical milling technique followed by sonication. Three different HEA-Graphene (HEA-G) composites were produced with the metal-to-graphene weight ratio of 50:50, 70:30 and 90:10. As-synthesized HEA-G composites were extensively characterized through microscopy (AFM and TEM) and spectroscopic (Raman) techniques to understand the HEA nanoparticle formation and distribution over the surface of graphene sheets. Further, the catalytic behaviour of HEA-G composites was examined using cyclic voltammetry (CV) and chronoamperometry (CA) to understand the non-enzymatic oxidation of urea using the HEA-G composites. The onset of the catalytic behaviour was observed with the composite 50:50 which was increased till 70:30 composite. However, the 90:10 composition exhibited minimal catalytic response compared to the other two composites. The composite 70:30 being the best performer was used to derive sensitivity based on the oxidation of urea which was found to be 37.4 μAm M−1 cm−2. The current study opens the window to explore a new class of all possible HEA nanocomposites for electrocatalytic applications.
•High entropy alloy (NiFeCrCoCu) nanoparticleengineered graphene (HEA-G) composites produced by simple and effective ballmilling technique.•Electrocatalyticperformance of HEA-G composites towards oxidation of urea.•The variation of HEAnanoparticle and graphene weight percentage as a composite to enhance thecatalytic behaviour.•HEA-G compositeexhibit better working potential and sensitivity for urea detection.
The formation of Fe₃O₄ nanoparticles by hydrothermal process has been studied. X-ray Diffraction measurements were carried out to distinguish between the phases formed during the synthesis. Using the ...synthesized Fe₃O₄ nanoparticles, poly(vinyledene fluoride)-Fe₃O₄ composite films were prepared by spin coating method. Scanning electron microscopy of the composite films showed the presence of Fe₃O₄ nanoparticles in the form of aggregates on the surface and inside of the porous polymer matrix. Differential Scanning calorimetry revealed that the crystallinity of PVDF decreased with the addition of Fe₃O₄. The conductitivity of the composite films was strongly influenced by the Fe₃O₄ content; conductivity increased with increase in Fe₃O₄ content. Vibration sample magnetometry results revealed the ferromagnetic behavior of the synthesized iron oxide nanoparticles with a Ms value of 74.50 emu/g. Also the presence of Fe₃O₄ nanoparticles rendered the composite films magnetic.
Polyethylene tetraphthalate (PET) bottles, a major environmental pollutant from the food industry, has been used as an activated carbon source in the current work. The specific surface area of the ...activated carbon has been analyzed using N2 adsorption/desorption isotherms, at different sonication time periods. A high surface area of 899 m2 g-1 with microporosity has been achieved for 20 h sonication followed by activation at 800 °C. To further enhance the material performance, carbon doped MoS2 (MoS2–C), using conventional hydrothermal technique has been synthesized. Different composite ratios of activated carbon and MoS2-C have been tested using electrochemical impedance spectroscopy and the best ratio owing to lesser charge-transfer resistance has been chosen for supercapacitor and HER analysis. The porous network of the plastic derived activated carbon (PAC) with a few layers of MoS2–C contributes significantly to the increase in the power density (469 W kg-1). By inducing defects on the material surface, there has been a significant enhancement in the electrocatalytic activity on PAC and this facilitates HER on its surface. Subsequently, the HER activity of the PDAC/MoS2–C composite has also been reported. Here, the PDAC defective sites along with the hexagonal MoS2–C’s largely exposed reactive edges indicate a reduction in the overpotential and Tafel values of −195 mV and −82 mVdec−1, suggesting that the material under investigation is a good catalyst for electrochemical HER. Also, this article reports for the first-time, HER activity of defect induced plastic derived activated carbon and its excellent catalytic activity.
•Plastic derived activated carbon (PAC) synthesized via KOH activation technique.•MoS2–C nanoflowers grown via hydrothermal technique using water - ethylene glycol mixture.•HER achieved on activated carbon creating defective sites on PAC (PDAC).•The composites of PDAC/MoS2–C catalyzed HER at −195 mV overpotential and −82 mVdec−1 Tafel slope values.•Composite formation of PAC and MoS2–C for enhanced symmetric, hybrid supercapacitor and HER.
The 5-hydroxytryptamine 3 (5-HT3) receptor belongs to the pentameric ligand-gated cation channel superfamily. Humans have five different 5-HT3 receptor subunits: A to E. The 5-HT3 receptors are ...located on the cell membrane, but a previous study suggested that mitochondria could also contain A subunits. In this article, we explored the distribution of 5-HT3 receptor subunits in intracellular and cell-free mitochondria. Organelle prediction software supported the localization of the A and E subunits on the inner membrane of the mitochondria. We transiently transfected HEK293T cells that do not natively express the 5-HT3 receptor with an epitope and fluorescent protein-tagged 5HT3A and 5HT3E subunits. Fluorescence microscopy and cell fractionation indicated that both subunits, A and E, localized to the mitochondria, while transmission electron microscopy revealed the location of the subunits on the mitochondrial inner membrane, where they could form heteromeric complexes. Cell-free mitochondria isolated from cell culture media colocalized with the fluorescent signal for A subunits. The presence of A and E subunits influenced changes in the membrane potential and mitochondrial oxygen consumption rates upon exposure to serotonin; this was inhibited by pre-treatment with ondansetron. Therefore, it is likely that the 5-HT3 receptors present on mitochondria directly impact mitochondrial function and that this may have therapeutic implications.
Abstract The delivery of curcumin, a broad-spectrum anticancer drug, has been explored in the form of liposomal nanoparticles to treat osteosarcoma (OS). Curcumin is water insoluble and an effective ...delivery route is through encapsulation in cyclodextrins followed by a second encapsulation in liposomes. Liposomal curcumin's potential was evaluated against cancer models of mesenchymal (OS) and epithelial origin (breast cancer). The resulting 2-Hydroxypropyl-γ-cyclodextrin/curcumin - liposome complex shows promising anticancer potential both in vitro and in vivo against KHOS OS cell line and MCF-7 breast cancer cell line. An interesting aspect is that liposomal curcumin initiates the caspase cascade that leads to apoptotic cell death in vitro in comparison with DMSO-curcumin induced autophagic cell death. In addition, the efficiency of the liposomal curcumin formulation was confirmed in vivo using a xenograft OS model. Curcumin-loaded γ-cyclodextrin liposomes indicate significant potential as delivery vehicles for the treatment of cancers of different tissue origin. From the Clinical Editor Curcumin-loaded γ-cyclodextrin liposomes were demonstrated in vitro to have significant potential as delivery vehicles for the treatment of cancers of mesenchymal and epithelial origin. Differences between mechanisms of cell death were also evaluated.
Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) RNA‐dependent RNA polymerase (RdRp) has been identified to be a mutation hot spot, with the P323L mutation being commonly observed in ...viral genomes isolated from North America. RdRp forms a complex with nonstructural proteins nsp7 and nsp8 to form the minimal replication/transcription machinery required for genome replication. As mutations in RdRp may affect formation of the RdRp–nsp7–nsp8 supercomplex, we analyzed viral genomes to identify mutations in nsp7 and nsp8 protein sequences. Based on in silico analysis of predicted structures of the supercomplex comprising of native and mutated proteins, we demonstrate that specific mutations in nsp7 and nsp8 proteins may have a role in stabilization of the replication/transcription complex.
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