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Access to clean water is the mandatory requirement for every living being to sustain life. So, membrane-based integrated approach of adsorption and separation technology has recently been preferred by scientists over other conventional techniques, for wastewater treatment. Current research focused on the synthesis of novel imidazolium (A1) based IL, which was further functionalized with hydroxyapatite (HAp; extracted from Labeo rohita scales), to create possible solutions towards environmental remediation. Cellulose acetate (CA) was used for the fabrication of three different ionic liquid membranes. All the synthesized products were characterized by FTIR, XRD and TGA. Two dyes of different nature, i.e., congo red (anionic) and crystal violet (cationic) were selected because of their highly toxic and carcinogenic effects, for batch adsorption experiments. Antibacterial activity of the synthesized membranes was also evaluated against S. aureus. Results of the study revealed that CA-HA1 1:2 acted as the best adsorbent towards the removal of crystal violet, exhibiting removal efficiency of 98% with the contact time of 24 h while in case of congo red adsorption, CA-HA1 (1:2) proved as prime adsorbent with the removal efficiency of 96% for the same preceding contact time. Considering the antibacterial character of the synthesized membranes, CA-A1 (1:1) emerged as very efficient antibacterial agent with the inhibition zone of 50 mm after 48 h. The overall behavior of monolayer and multilayer adsorption was witnessed for both dyes while kinetic studies favored the pseudo-second order reaction for all adsorbents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In the present research, the structural, electronic and optical properties of transition metal dichalcogenide-doped transition metal oxides MoS 2 -doped-V 2 O 5 with various doping concentrations ( x = 1-3%) of MoS 2 atoms are studied by using first principles calculation. The generalized gradient approximation Perdew-Burke-Ernzerhof simulation approach is used to investigate the energy bandgap ( E g ) of orthorhombic structures. We examined the energy bandgap ( E g ) decrement from 2.76 to 1.30 eV with various doping ( x = 1-3%) of molybdenum disulfide (MoS 2 ) atoms. The bandgap nature shows that the material is a well-known direct bandgap semiconductor. MoS 2 doping ( x = 1-3%) atoms in pentoxide (V 2 O 5 ) creates the extra gamma active states which contribute to the formation of conduction and valance bands. MoS 2 -doped-V 2 O 5 composite is a proficient photocatalyst, has a large surface area for absorption of light, decreases the electron-hole pairs recombination rate and increases the charge transport. A comprehensive study of optical conductivity reveals that strong peaks of MoS 2 -doped-V 2 O 5 increase in ultraviolet spectrum region with small shifts at larger energy bands through increment doping x = 1-3% atoms of MoS 2 . A significant decrement was found in the reflectivity due to the decrement in the bandgap with doping. The optical properties significantly increased by the decrement of bandgap ( E g ). Two-dimensional MoS 2 -doped-V 2 O 5 composite has high energy absorption, optical conductivity and refractive index, and is an appropriate material for photocatalytic applications., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The accumulation of Cr(VI) ions in water can cause serious influences on the environment and human health. This work reports a humble synthesis of ZnSe nanoparticles anchored to the sol-gel prepared TiO 2 for visible-light-driven photocatalytic reduction of Cr(VI) ions. The 7.9 nm ZnSe nanoparticles were attached to TiO 2 surfaces at a content of 1.0-4.0 wt% as experiential by TEM investigation. The designed nanocomposite unveiled mesostructured surfaces exhibiting surface areas of 176-210 m 2 g -1 . The impregnation of ZnSe amended the visible-light absorption of TiO 2 due to the bandgap decrease from 3.14 to 2.90 eV. The photocatalytic reduction of Cr(VI) applying the optimized portion of 3.0 wt% ZnSe/TiO 2 was achieved at 177 μ mol min -1 . This photocatalytic activity is higher than the common Degussa P25 and pristine TiO 2 by 20 and 30 times, respectively. The improved performance is signified by the efficient interfacial separation of charge carriers by the introduction of ZnSe. This innovative ZnSe/TiO 2 has also shown photocatalytic stability for five consecutive runs., (© 2022 IOP Publishing Ltd.)

In this study, a high-density ZrN/ZrSi 2 composite reinforced with ZrO 2 as an inert phase was synthesized under vacuum starting with a Zr-Si 4 N 3 -ZrO 2 blend using combustion-synthesis methodology accompanied by compaction. The effects of ZrO 2 additions (10-30 wt%) and compression loads (117-327 MPa) on the microstructure, porosity and hardness of the samples were studied. The process was monitored using XRD, SEM, EDS, porosity, density and hardness measurements. Thermodynamic calculations of the effect of ZrO 2 addition on the combustion reaction were performed including the calculation of the adiabatic temperatures and the estimation of the fractions of the liquid phase. The addition of up to 20 wt% ZrO 2 improved the hardness and reduced the porosity of the samples. Using 20 wt% ZrO 2 , the sample porosity was reduced to 1.66 vol%, and the sample hardness was improved to 1165 ± 40.5 HV at 234 MPa.

In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (T c ), spin polarization, half magnetic ferromagnetism and transport properties of ZnX 2 Se 4 (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of T c is perceived for ZnCr 2 Se 4 . The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) μ B of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy ΔE crystal , exchange energies Δ x ( d ), Δ x ( pd ) and exchange constants (N o α and N o β). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0-400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 10 11 W/mK 2 ) among studied compounds.

Tapioca processing industries are very popular in the rural community to produce a variety of foods as the end products. Due to their small scales and scattered locations, they require robust modular systems to operate at low capacity with minimum supervision. This study explores the application of a novel sequencing batch-integrated fixed-film activated sludge membrane (SB-IFASM) process to treat tapioca processing wastewater for reuse purposes. The SB-IFASM employed a gravity-driven system and utilizes biofilm to enhance biodegradation without requiring membrane cleaning. The SB-IFASM utilizes the biofilm as a secondary biodegradation stage to enhance the permeate quality applicable for reuse. A lab-scale SB-IFASM was developed, preliminarily assessed, and used to treat synthetic tapioca processing industry wastewater. The results of short-term filtration tests showed the significant impact of hydrostatic pressure on membrane compaction and instant cake layer formation. Increasing the pressure from 2.2 to 10 kPa lowered the permeability of clean water and activated sludge from 720 to 425 and from 110 to 50 L/m 2 ·h bar, respectively. The unsteady-state operation of the SB-IFASM showed the prominent role of the bio-cake in removing the organics reaching the permeate quality suitable for reuse. High COD removals of 63-98% demonstrated the prominence contribution of the biofilm in enhancing biological performance and ultimate COD removals of >93% make it very attractive for application in small-scale tapioca processing industries. However, the biological ecosystem was unstable, as shown by foaming that deteriorated permeability and was detrimental to the organic removal. Further developments are still required, particularly to address the biological stability and low permeability.

The preparation of a dextran (Dex)-hydroxyethyl cellulose (HEC) blend impregnated with ammonium bromide (NH 4 Br) is done via the solution cast method. The phases due to crystalline and amorphous regions were separated and used to estimate the degree of crystallinity. The most amorphous blend was discovered to be a blend of 40 wt% Dex and 60 wt% HEC. This polymer blend serves as the channel for ions to be conducted and electrodes separator. The conductivity has been optimized at (1.47 ± 0.12) × 10 -4 S cm -1 with 20 wt% NH 4 Br. The EIS plots were fitted with EEC circuits. The DC conductivity against 1000/T follows the Arrhenius model. The highest conducting electrolyte possesses an ionic number density and mobility of 1.58 × 10 21 cm -3 and 6.27 × 10 -7 V -1 s -1 cm 2 , respectively. The TNM and LSV investigations were carried out on the highest conducting system. A non-Faradic behavior was predicted from the CV pattern. The fabricated electrical double layer capacitor (EDLC) achieved 8000 cycles, with a specific capacitance, internal resistance, energy density, and power density of 31.7 F g -1 , 80 Ω, 3.18 Wh kg -1 , and 922.22 W kg -1 , respectively.

The efficacy of LaNaTaO 3 perovskites decoration RuO 2 at diverse contents for the photocatalytic H 2 generation has been explored in this study. The photocatalytic performance of RuO 2 co-catalyst onto mesoporous LaNaTaO 3 was evaluated for H 2 under UV illumination. 3%RuO 2 /LaNaTaO 3 perovskite photocatalyst revealed the highest photocatalytic H 2 generation performance, indicating that RuO 2 nanoparticles could promote the photocatalytic efficiency of LaNaTaO 3 perovskite significantly. The H 2 evolution rate of 3%RuO 2 /LaNaTaO 3 perovskite is 11.6 and 1.3 times greater than that of bare LaNaTaO 3 perovskite employing either 10% CH 3 OH or pure H 2 O, respectively. Interestingly, the photonic efficiency of 3%RuO 2 /LaNaTaO 3 perovskite was enhanced 10 times than LaNaTaO 3 perovskite in the presence of aqueous CH 3 OH solutions as a hole sacrificial agent. The high separation of charge carriers is interpreted by the efficient hole capture using CH 3 OH, hence leading to greater H 2 generation over RuO 2 /LaNaTaO 3 perovskites. This is attributed to an adjustment position between recombination electron-hole pairs and also the reduction of potential conduction alignment as a result of RuO 2 incorporation. The suggested mechanisms of RuO 2 /LaNaTaO 3 perovskites for H 2 generation employing either CH 3 OH or pure H 2 O were discussed. The photocatalytic performances of the perovskite photocatalyst were elucidated according to the PL intensity and the photocurrent response investigations., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Vanadium carbide is known, for its hardness and other unique properties, as a refractory material. The synthesis of vanadium carbide is always associated with the utilization of expensive active metals, such as aluminum, calcium and magnesium, as a reducing agent to extract the vanadium metal from its corresponding oxide, followed by carbidization. The carbidization of reduced vanadium requires a complicated process and elevated temperature. Mechanical activation to synthesize vanadium carbide from its corresponding oxide and carbon source represents a promising, straightforward and less energy-intensive route. In the present study, vanadium carbide is synthesized by the carbothermic reduction of a mechanically activated mixture of V 2 O 5 and carbon black as reducing agents without any additives. The reduction process is monitored by means of thermogravimetric analysis. The reduction products are characterized by X-ray diffraction and field emission scanning electron microscope. It is found that V 8 C 7 with an average crystallite size of 88 nm can be synthesized from a V 2 O 5 -C mixture after milling for 15 h and further heating at 1050 °C for 1 h in an inert atmosphere.