Enhanced photocatalytic performance of CuFeO2-ZnO heterostructures for methylene blue degradation under sunlight

One of the strategies to overcome the drawbacks of fast charge recombination of a photocatalyst is to develop semiconductor heterostructures. Herein, we report a two-step precipitation-hydrothermal process to create CuFeO₂-ZnO heterostructures with different weight percentages of CuFeO₂ (0.5, 1, 5, and 10%). Though X-ray diffraction detected the presence of CuFeO₂ on ZnO above 5%, Raman spectroscopy could reveal the presence of CuFeO₂ phase as low as 0.5 wt%. For all of the compositions, the bandgap of ZnO did not vary (3.15 eV) on forming heterostructures with CuFeO₂. The oxidation of methylene blue under sunlight was used to determine the photocatalytic performance of the heterostructures. In comparison to pure ZnO and CuFeO₂, CuFeO₂-ZnO heterostructures exhibited a better photocatalytic efficiency. Overall, 5 wt% CuFeO₂ on ZnO showed 100% degradation with a rate constant of 0.272?±?0.002 min^?1, which is 16 times faster than ZnO. Time-resolved photoluminescence analysis indicated a higher lifespan of charge carriers in the 5wt% CuFeO₂-ZnO heterostructure (32.3 ns) than that of CuFeO₂ (0.85 ns) and ZnO (27.6 ns). The Mott–Schottky flat band potentials of ZnO and CuFeO₂ was determined to be -0.82 and 1.17 eV, respectively, revealing the presence of Type I heterostructures. The heterostructures also showed outstanding recyclability, with a degradation rate of 97% even after four cycles. The current study shows the significance of forming p-type CuFeO₂ and n-type ZnO heterostructures for enhanced photocatalysis.

     

Fluid overload and acute kidney injury

Acute kidney injury is commonly encountered in critically ill patients, and is associated with worse outcomes. Fluid therapy is a key component in the management of these patients, often leading to fluid overload, especially in the setting of septic acute kidney injury. Emerging data overwhelmingly suggest that fluid overload in these patients may be associated with adverse outcomes. Management of such patients should include a strategy of early guided resuscitation, followed by careful assessment of fluid status, and early initiation of renal replacement therapy as soon as it is deemed safe, aiming for a neutral or negative fluid balance. This review will focus on the pathophysiological link between fluid overload and acute kidney injury, mechanisms of organ dysfunction in fluid overload, and strategies for management.     

Fabrication,characterization and application of pectin degrading Fe3O4–SiO2 nanobiocatalyst

The covalent binding of pectinase onto amino functionalized silica-coated magnetic nanoparticles (CSMNPs) through glutaraldehyde activation was investigated for nanobiocatalyst fabrication. The average particle size and morphology of the nanoparticles were characterized using transmission electron microscopy (TEM). The statistical analysis for TEM image suggests that the coating and binding process did not cause any significant change in size of MNPs. The morphological and phase change of the magnetic nanoparticles (MNPs) after various coatings and immobilization were characterized by X-ray diffraction (XRD) studies. The various surface modifications and pectinase binding onto nanoparticles were confirmed by Fourier transform infrared (FT-IR) spectroscopy. The maximum activity of immobilized pectinase was obtained at its weight ratio of 19.0 × 10^? 3 mg bound pectinase/mg CSMNPs. The pH, temperature, reusability, storage ability and kinetic studies were established to monitor their improved stability and activity of the fabricated nanobiocatalyst. Furthermore, the application was extended in the clarification of Malus domestica juice.     

Nonlocal nonlinear bending and free vibration analysis of a rotating laminated nano cantilever beam

In this article, we present the nonlocal, nonlinear finite element formulations for the case of nonuniform rotating laminated nano cantilever beams using the Timoshenko beam theory. The surface stress effects are also taken into consideration. Nonlocal stress resultants are obtained by employing Eringen’s nonlocal differential model. Geometric nonlinearity is taken into account by using the Green Lagrange strain tensor. Numerical solutions of nonlinear bending and free vibration are presented. Parametric studies have been carried out to understand the effect of nonlocal parameter and surface stresses on bending and vibration behavior of cantilever beams. Also, the effects of angular velocity and hub radius on the vibration behavior of the cantilever beam are studied.     

PLGA nanodepots co-encapsulating prostratin and anti-CD25 enhance primary natural killer cell antiviral and antitumor function

Nano Research - Natural killer (NK) cells are attractive effector cells of the innate immune system against human immunodeficiency virus (HIV) and cancer. However, NK cell therapies are limited by...     

Etched Triangle Resonator Dual Band Microstrip Band Pass Filter

Wireless Personal Communications - Increasing demand for mobility and high data rates has brought more attention and the need for wireless technologies. Ultra-Wide Band (UWB) waveforms have the...     

Vertical Handover Analysis Using Modified MADM Method in LTE

Ubiquitous Communication is being a trend in this era. It is possible anywhere anytime with the sustenance and by the agreement of different service providers of Mobile technology. A mobile node which is attached to its base station relinquishes its connection while continuous mobility causes a fluctuation of signal strength. To overcome this issue, heterogeneous networks provision is obligatory. Normally Base stations serve several mobile nodes. Whenever a base station cannot handle a mobile terminal, it will assign its node to nearby available base station for service. The process of assignment of mobile nodes to another base station is termed as Heterogeneous handover. This type of Handover is needed for seamless integration of networks. LTE has proved promising outcomes in providing successful handover, Since it uses eNodeB infrastructure. In this work, Received signal strength is taken as main measure and analysed. Received Power acts as the building block for making possible handover across heterogeneous Radio Access Technologies. Proposed method suggests a vertical handover based on various signal measures. Enhanced Weighted Sum Method is incorporated for Handover decision making. Several criteria also utilized.

     

Low-cost and biodegradable cellulose/PVP/activated carbon composite membrane for brackish water treatment

A simple fabrication of a biodegradable membrane for use in water purification systems is presented in this work. Sodium carboxymethyl cellulose and PVP are dissolved in water and crosslinked with citric acid. The presence of glycerol has given immense flexibility and mechanical strength to the membrane. The addition of activated charcoal has enhanced its purification and dye adsorption capabilities at room temperature in dark and light conditions. The polymer semiconductor composites are completely soil degradable within a week and the membrane also exhibits good electrical conductivity when compared to the membrane without charcoal. The addition of glycerol has acted as molecular spacer between polymers composite's monomer backbone that allows good electron mobility of 9.9 cm² V⁻¹ s⁻¹. The dye adsorption efficiency of the material with two commonly used toxic textile dyes is found to be 100% for methyl orange and up to 57% for Rhodamine B within 3 h. The material shows good dye adsorption efficiency under dark and light conditions with acidic, neutral, and alkaline pH. Salt rejection was also found to increase from 25.3 to 64.4% with applied voltage. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48746.