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In the present study, nickel ferrite (NiFe2O4)-based smart magnetic nanoparticles were fabricated and coated with methionine. Physiochemical characterization of the obtained Met-NiFe2O4 nanoparticles revealed the presence of methionine coating over the nanoparticle surface. Drug release study indicated that Tet-Met-NiFe2O4 nanoparticles possess pH-responsive controlled drug release behavior for tetracycline (Tet). The drug loading content for Tet was found to be 0.27 mg/L of nanoparticles. In vitro cytotoxicity test showed that the Met-NiFe2O4 nanoparticles is biocompatible. Moreover, this magnetic nanostructured material shown strong anticancer property as these nanomaterials significantly reduced the viability of A375 cells when compared to free Tet solution. In addition, Tet-Met-NiFe2O4 nanoparticles also showed strong antibacterial activity against different bacterial pathogens. [ABSTRACT FROM AUTHOR]

A drain current local variability compact model due to random fluctuation of channel length induced by line edge roughness/line width roughness (LER/LWR) is derived here. The random fluctuation of channel length leads to correlated fluctuations of threshold voltage and effective mobility of the current carriers. Therefore, an unified compact model is required to combine all the causes. Our model is based on the principle of propagation of variance. For the model verification purpose, calibrated technology computer aided design (TCAD) simulation platform is extensively used for all possible bias regions and several LER profile parameters. Channel profile optimization is critically studied with respect to different LER parameters, aiming reduction of ID variability. The model is further extended for SOI (Silicon-on-insulator) transistor and validated with literature data of threshold voltage and on-current variability. [ABSTRACT FROM AUTHOR]

Around the world, countries are making efforts to tackle immediate environmental concerns such as global warming and its impact on climate change, as well as the challenge of fast-depleting fossil fuel resources. Moreover, these nations strive to achieve complete elimination of greenhouse gases, considering the context of the ongoing and escalating global energy crisis. As a result, researchers are investigating bio-based feedstocks as viable and environmentally friendly alternatives for bioenergy production. Microalgae are a type of photosynthetic microorganism that could be used as a renewable energy resource. They are capable of growing in harsh environmental circumstances and on terrain that is not suitable for agriculture. Additionally, they tend to flourish in both seawater and wastewater. Microalgae exhibit superior photosynthetic efficiency and biomass productivity in comparison to their terrestrial plant counterparts. Microalgae biomass, as well as the metabolites derived from it, can be transformed into a range of biofuels, including bioethanol, biodiesel, crude oil, pyrolytic bio-oil, biomethane, biohydrogen, and jet biofuel. Nevertheless, numerous obstacles still need to be overcome to attain faster and more widespread commercial utilization of microalgae as a renewable bioenergy source for bioethanol production. To enhance the sustainability of the environment and economic feasibility of microalgal bioethanol, it is crucial to choose suitable microalgal bio jets, create methods for concentrating biomass, and utilize wet microalgal biomass for bioethanol production. All these methods and steps need to be carried out meticulously. Additionally, adopting a coordinated biorefinery approach to produce value-added products would further contribute to the identified goals. This article aims to provide an overview of the present state of research on microalgal bioethanol and its prospects. [ABSTRACT FROM AUTHOR]

The release of petroleum and petroleum derivatives, such as polycyclic aromatic hydrocarbons (PAHs), in the environment owing to anthropogenic activities, has become a major global threat to human health and ecological equilibrium. It causes a number of diseases and petroleum hydrocarbon (PH) compounds bind to soil components, making their removal very difficult. In order to find an eco-friendly, convenient, and non-expensive way, indigenous PH degrading microorganisms are employed. Biofilm, being a syntrophic association plays an important role in PAH degradation. The three-dimensional structure of the biofilm matrix is found to facilitate the efficient and rapid degradation of PAH. Various physicochemical parameters of biofilm are found to regulate the efficacy of PAH degradation. In order to amend certain drawbacks of biofilm mediated remediation, these days microbial electrochemical systems are increasingly being used for redressal of PH contamination, where the solid anode functions as an endless electron acceptor and the microbial activity is stimulated by bio-current in situ to guarantee the PH removal from contaminated soil and water. Following uptake of emulsified PH, it may be denatured by biofilm-associated enzymes or by biosurfactant molecules (such as rhamnolipids). The biomolecules synthesized by the bacterial cells further help in the expression of the specific genes thereby helping in the enhancement of PH degradation. [ABSTRACT FROM AUTHOR]

Anaerobic digestion is a traditional method of producing methane-containing biogas by utilizing the methanogenic conversion of organic matter like agricultural waste and animal excreta. Recently, the application of microbial electrolysis cell (MECs) technology to a traditional anaerobic digestion system has been extensively studied to find new opportunities in increasing wastewater treatability and methane yield and producing valuable chemicals. The finding that both anodic and cathodic bacteria can synthesize methane has led to the efforts of optimizing multiple aspects like microbial species, formation of biofilms, substrate sources and electrode surface for higher production of the combustible compound. MECs are very fascinating because of its ability to uptake a wide variety of raw materials including untreated wastewater (and its microbial content as biocatalysts). Extensive work in this field has established different systems of MECs for hydrogen production and biodegradation of organic compounds. This review is dedicated to explaining the operating principles and mechanism of the MECs for electromethanogenesis using different biochemical pathways. Emphasis on single- and double-chambered MECs along with reactor components is provided for a comprehensive description of the technology. Methane production using hydrogen evolution reaction and nanocatalysts has also been discussed. [ABSTRACT FROM AUTHOR]

Microbial electrocatalysis reckons on microbes as catalysts for reactions occurring at electrodes. Microbial fuel cells and microbial electrolysis cells are well-known in this context; both prefer the oxidation of organic and inorganic matter for producing electricity. Notably, the synthesis of high energy-density chemicals (fuels) or their precursors by microorganisms using biocathode to yield electrical energy is called Microbial Electrosynthesis (MES), giving an exceptionally appealing novel way for producing beneficial products from electricity and wastewater. This review accentuates the concept, importance and opportunities of MES, as an emerging discipline at the nexus of microbiology and electrochemistry. Production of organic compounds from MES is considered as an effective technique for the generation of various beneficial reduced end-products (like acetate and butyrate) as well as in reducing the load of CO2 from the atmosphere to mitigate the harmful effect of greenhouse gases in global warming. Although MES is still an emerging technology, this method is not thoroughly known. The authors have focused on MES, as it is the next transformative, viable alternative technology to decrease the repercussions of surplus carbon dioxide in the environment along with conserving energy. [ABSTRACT FROM AUTHOR]

Nowadays, the world is experiencing an energy crisis due to extensive globalization and industrialization. Most of the sources of renewable energy are getting depleted, and thus, there is an urge to locate alternative routes to produce energy efficiently. Microbial fuel cell (MFC) is a favorable technology that utilizes electroactive microorganisms acting as a biocatalyst at the anode compartment converting organic matter present in sewage water for bioelectricity production and simultaneously treating wastewater. However, there are certain limitations with a typical stand-alone MFC for efficient energy recovery and its practical implementation, including low power output and high cost associated with treatment. There are various modifications carried out on MFC for eliminating the limitations of a stand-alone MFC. Examples of such modification include integration of microbial fuel cell with capacitive deionization technology, forward osmosis technology, anaerobic digester, and constructed wetland technology. This review describes various integrated MFC systems along with their potential application on an industrial scale for wastewater treatment, biofuel generation, and energy production. As a result, such integration of MFCs with existing systems is urgently needed to address the cost, fouling, durability, and sustainability-related issues of MFCs while also improving the grade of treatment received by effluent. [ABSTRACT FROM AUTHOR]

In the 21st century, hybrid nanocomposites were widely used in bioelectronic, biosensing, photocatalytic, and biomedical applications. In the present study, we fabricated a novel Fe3O4/PVA/Eggshell hybrid nanocomposite and physicochemically characterized it using powder XRD, EDS, FTIR, VSM, and HR-TEM analysis. The XRD spectrum revealed the crystalline and FCC configuration of Fe3O4 NPs with average crystal size of 16.28 nm, and the HRTEM image indicates the prepared hybrid nanocomposite is of spherical shape with less agglomeration. This hybrid nanocomposite showed a significant photodegradation property in degrading organic pollutants such as congo red and crystal violet dyes under the sunlight irradiation. In addition, the hybrid nanocomposite also displayed a potent antibacterial property against different Gram +ve and Gram −ve bacterial pathogens. This study provides a significant example in the overview of fabrication of cost effectively, eco-friendly, and multiple-application hybrid nanocomposites through eggshell membrane fibers. [ABSTRACT FROM AUTHOR]

In this work, with the help of extensive technology computer-aided design simulations, we report a comprehensive study of MOSFET based circuit design using ultra-thin body III-V on-insulator (OI) CMOS transistors. We demonstrate the circuit performance of III-V CMOS by combining InAs-OI n-channel and GaAs-OI junction-less p-channel transistors. The performance metrics of different circuits designed using III-V transistors are also compared with III-V/Germanium and Silicon-on-insulator (SOI) based CMOS logic. CMOS inverter circuit designed using III-V/Ge (InAs-OI/GeOI) CMOS shows 51% and 17% reduction in rise and fall time compared to SOI CMOS. The oscillation frequency of the ring oscillator designed using III-V/Ge (InAs-OI/GeOI) and III-V (InAs-OI/GaAs-OI) CMOS logic is approximately three times and two times higher than SOI based design. The unity-gain bandwidth of the inverting amplifier using III-V/Ge (InAs-OI/GeOI) and III-V (InAs-OI/GaAs-OI) architecture is 22 times and 9.5 times higher compared to SOI CMOS based circuit. Static noise margin (SNM) of conventional six-transistor (6-T) SRAM cell is also analyzed during hold operation. Due to the poor electrostatic integrity of III-V transistors, degradation in SNM is observed compared to its SOI counterparts. The cascode low noise amplifier (LNA) circuit designed using InAs-OI transistor shows the higher gain and low noise figure at the same operating frequency compared to the SOI transistor-based LNA. [ABSTRACT FROM AUTHOR]

For decades, one of the most pressing issues has been air pollution, which is responsible for more than six million fatalities per year worldwide. Biofuels are currently the advanced alternatives that ensure energy security while reducing air pollution-reducing the world's reliance on fossil fuels. Biomethanol is one of the most reliable biomass products, and the process of converting biomass to biofuel is known as a biorefinery. Biorefinery methods for converting individual biomass into biomethanol are being developed because the output of biomethanol involves various discrete processes that fall under the category of biorefinery. This review focuses on the various types of biomasses that can produce biomethanol, as well as the procedures involved in converting each biomass into biomethanol. We have addressed all available and unexplored biorefinery solutions for the generation of biomethanol. The economic advantages, environmental impact factors, and biomethanol assessment through waste biomass feedstock are examined and discussed. • Biorefinery methods for converting waste biomass into biomethanol. • Biomethanol via lignocellulose and waste biomass by thermochemical conversion process. • Conversion of methane/biogas to biomethanol. • Techno-economical assessment for industrial scale biomethanol production. • The economic advantages, environmental impact factors, and assessment. [ABSTRACT FROM AUTHOR]

Granular activated carbon (GAC) has been widely used at the anode of a microbial fuel cell (MFC) to enhance anode performance due to its outstanding capacitance property. To the best of our knowledge, there haven't been any studies on GAC in the cathode for biofilm development and nitrate reduction in MFC. In this study, by adding GAC to biocathode, we investigated the impact of different GAC amounts and stirring speeds on power generation and nitrate reduction rate in MFC. The denitrification rate was found to be nearly two-times higher in MFCs with GAC (0.046 ± 0.0016 kg m−3 d−1) compared to that deprived of GAC (0.024 ± 0.0012 kg m−3 d−1). The electrotrophic denitrification has produced a maximum power density of 37.6 ± 4.8 mW m−2, which was further increased to 79.2 ± 7.4 mW m−2 with the amount of GAC in the biocathode. A comparative study performed with chemical catalyst (Pt carbon with air sparging) cathode and GAC biocathode showed that power densities produced with GAC biocathode were close to that with Pt cathode. Cyclic voltammetry analysis conducted at 10 mV s−1 between −0.9 V and +0.3 V (vs. Ag/AgCl) showed consistent reduction peaks at −0.6V (Ag/AgCl) confirming the reduction reaction in the biocathode. This demonstrates that the GAC biocathode used in this research is effective at producing power density and denitrification in MFC. Our belief that the nitrate reduction was caused by the GAC biocathode in MFC was further strengthened when SEM analysis showing bacterial aggregation and biofilm formation on the surface of GAC. The GAC biocathode system described in this research may be an excellent substitute for MFC's dual functions of current generation and nitrate reduction. [Display omitted] • Biocathode catalyzed electrotrophic denitrification was studied in MFC. • GAC played an excellent current mediator resulting in high denitrification and power generation. • The performance improved with increase in content and stirring speed of GAC in cathode. • Results suggest GAC-biocathode can replace Pt cathode in bioelectrochemical cells. • Possible electrons exchange between electroactive bacteria and GAC through direct contact. [ABSTRACT FROM AUTHOR]