Concentration Of Nanoparticles Research Articles

Effects of aggregation and settling of photoactive TiO2 nanoparticles on Microcystis aeruginosa and extracellular matters release

Owing to their diverse applications, TiO2-nanoparticles have been extensively discharged into the aquatic environment, posing serious threats to aquatic life and human health. Meanwhile, the aquatic organisms such as cyanobacteria affect the mobility and fate of the nanoparticles, in turn, these aquatic organisms also may be influenced by the nanoparticles, and which further elicits more hazard to ecosystem. In this study, the different concentration of TiO2 nanoparticles were added into the algal solution to observe the status of TiO2 nanoparticles and assess their influences, especially for photocatalytic toxicity on algal growth. The results demonstrated that algal cells and extracellular polymeric substances (EPS) simultaneously affected the TiO2 aggregation and settling in algae culture. In addition, TiO2 NPs inhibited the growth of algal cells through the multiple effects on the light adsorption, photosynthetic activity, oxidative stress and lipid peroxidation. Particularly, the reactive oxygen species generated by photoactive TiO2 NPs caused the changes of EPS and microcystin-LR (MC-LR) release, and these extracellular matters were crucial intermediate to the state of TiO2 NPs and algal cells growth. This study will not only be significant for understanding TiO2 behavior in the real aquatic environment but also be helpful for exploring the effects of TiO2 nanoparticles on cyanobacteria, especially for the released extracellular matters.

Melting and Heat Management of Phase Change Material Using Smart Ternary-Hybrid Coolant

This research investigates the effectiveness of using a smart ternary-hybrid nanofluid to enhance the melting rate and convective behavior of electrically conducting tin (Sn) in a rectangular enclosure under the influence of a uniform magnetic field. The enclosure has adiabatic vertical walls with hot and cold temperatures on the bottom and top walls. The finite element method (FEM) is used to solve the governing equations with appropriate boundary conditions using Galerkin's weighted residual approach. The study focuses on applying tin as the phase change material (PCM), with the highest temperature of 508 K, the lowest temperature of 503 K, and the melting interface temperature of 505 K. To enhance the heat transfer performance, tin-based ternary (graphene (G), silicon carbide (SiC), and nickel (Ni)) hybrid smart coolant is applied into the system. To investigate the mechanism of the melting and convective thermal transfer process, the results of the present study are reported with time for various values of the magnetic field (Ha) and solid concentration of ternary hybrid nanoparticle (). This study represents the streamlines, isothermal lines, melting interface, melting fraction, and heat transfer for the above-mentioned parameters. The results show that increasing the magnetic field reduces the rate of thermal transport by 38.96% at t = 4000s. However, at a particular time of 2500s, increasing the solid volume fraction of nanoparticles enhances the melting fraction by approximately 8.34%. Two regression equations are derived for the Nusselt number and melting fraction, with multiple response variables. This article improves understanding of natural convective heat transport during phase change processes for various coolants in different engineering applications.

Electrochemical detection of atrial natriuretic peptide-coated nanocarriers based on a molecularly imprinted polymer receptor thin film

Molecular imprinting polymers (MIPs) are biomimetic materials of great interest in the scientific and industrial fields for the development of innovative sensing strategies. Herein, we proposed a new sensing application by developing an electrochemical sensor using molecular imprinting (MI) technology for recognition of atrial natriuretic peptide (ANP) both as a free molecule in solution and attached to nanoparticle-based drug delivery systems (DDSs), aiming to provide fast and reliable information on the cell uptake of nanoparticles (NPs). As proof of concept, poly(lactic-co-glycolic acid) (PLGA) NPs were synthesized and used as nanocarriers for ischemic heart disease therapy were synthesized and then functionalized with ANP (named here as PLGA-NPs@ANP). The MIP receptor film was prepared by electrochemical polymerization of dopamine over the working area of a gold screen-printed electrode (AuSPE), using cyclic voltammetry (CV) technique. The construction of the ANP sensor was carefully optimized to enhance its performance, including the film thickness and the procedures for effective template extraction from the MIP matrix. The MIP biosensor presented a linear response against polymeric NPs (PLGA-NPs@ANP) concentration logarithm ranging from 4.0 μg mL-1 to 100 μg mL-1, with a sensitivity of – 0.0129 mA mL μg-1 decade-1 and an LOD < 4.0 μg mL-1. Furthermore, the developed MIP receptor film was able to discriminate ANP-functionalized nanocarriers from non-functionalized NPs.

Charge-patterned nanofiltration membranes with polystyrene sulfonate particles and polyethyleneimine in cross-linked polyvinyl alcohol

Removing salinity has always been a challenge for wastewater treatment. Utilizing nanofiltration (NF) membranes is a promising approach. However, currently available NF membranes are less effective in monovalent salt removal. In this study, work toward the initial aim of fabricating charge mosaic membranes led to charge-patterned NF-selective films on polyether sulfone (PES) or polyacrylonitrile (PAN) support membranes, with similar rejection for mono- and divalent salts. The membranes were fabricated by a two-step layer assembly of first negatively charged polystyrene sulfonate (PSS) particles immobilized in a polyvinyl alcohol (PVA) layer, followed by coating a positively charged polyethyleneimine (PEI) layer. Both PVA and PEI were crosslinked using glutaraldehyde that had initially been impregnated into the support membrane. The type of support membrane, nanoparticle, PVA, and PEI concentrations during fabrication, as well as feed pH and salt concentration, play significant roles in separation performance of obtained composite membranes. Charge-patterned NF membranes fabricated using 0.5 wt.% PVA and 0.05 wt.% PSS for assembly of the first layer followed by coating 0.5 wt.% PEI solution had even somewhat higher rejection for monovalent salt (NaCl; ∼82%) compared to multivalent salts (Na2SO4, MgSO4, and MgCl2; ∼74%), at a permeance of 5.5 LMH/bar on the PES and 3.1 LMH/bar on the PAN support membrane.

Dynamic light scattering unveils stochastic degradation in large-pore mesoporous silica nanoparticles

Mesoporous Silica Nanoparticles (MSNs) have been increasingly investigated as versatile drug delivery carriers. A particular challenge for the systemic use of MSNs lies in the control of their degradation, which has not been fully understood until now. We implemented standard dynamic light scattering (DLS) experiments and introduced a novel DLS technique in a confocal volume to track the dynamics of large-pore MSN degradation in situ. This unique DLS technique, which involves a small observation volume, was chosen for its ability to count particle by particle during the degradation process, a method that has not been commonly used in nanoparticle research. The experiments were performed in different media compositions at low particle concentrations, below the silica solubility limit. MSNs with large conical pores were prepared and studied as they offer the possibility to incorporate and release large-sized biomolecules. Large-pore MSNs followed a singular degradation mechanism following a stochastic-like behavior, a finding that challenges the common idea that all nanoparticles (NPs) degrade similarly and homogeneously over time. We showed that some NPs are observed intact over a prolonged period while most other NPs have already vanished or been transformed into swollen NPs. Thus, a heterogeneous degradation process occurs, while the total concentration of NPs undergoes an exponential decay. These large conical pores MSNs will be utilized as reliable biomolecule nanocarriers by predicting the factors underlying the NP hydrolytic stability.

Determination of operational flow regime and heat transfer performance optimization of mono and hybrid nanofluids using FOM and sensitivity analysis

Nanofluids are considered as the most suitable replacement for conventional coolants due to their augmented thermal properties. The current study focuses on the operational suitability of different nanofluids (45 nanofluids) and estimates their heat transfer performance through Figure of merit (FOM) analysis. To perform an FOM-based ranking of these nanofluids, the heat transfer coefficient, friction factor, and pumping power of several nanofluids were also calculated. The effect of varying the volumetric concentration (0.01–1 vol%) on the pumping power, heat transfer coefficient, and thermo-physical characteristics of several nanofluids was examined. Different process and design parameters like pressure drop, flow velocity, mass flow rate, internal channel diameter, fluid temperature gradient, and wall temperature of the system were varied to check their effect on heat transfer coefficient, friction factor, and pumping power. Based on the FOM analysis, the authors determined that the majority of the nanofluids (26 nanofluids) investigated can be used in both laminar and turbulent flow regimes. The heat transfer coefficient decreases with increasing nanoparticle concentration. Therefore, it is essential to keep the concentration at an optimum level to attain the desired heat transfer performance. Among various key findings from the study, authors reported that the friction factor and pumping power of the nanofluid increases when the pressure drops and the channel’s internal diameter increases, while with increasing flow velocity, the friction factor and pumping power decrease. The authors also suggest that the pressure drop should be limited to 1–1.003 bar, the flow velocity should be greater than 1.4–1.5 m/s and the internal diameter should be 0.02 m to maintain the friction factor below 0.1. The aforementioned parameters are crucial when optimizing the heat transfer performance of a cooling system using nanofluid as a coolant.

Advanced electrochemical synthesis and characterization of Al2O3 nanoparticles embedded in polyaniline matrix for optoelectronic applications

Nanocomposite materials, featuring conducting polymers and aluminum oxide nanoparticles (Al2O3-NPs), are revolutionizing various fields including biomedicine, optoelectronic devices, and dye adsorption. In this study, we report on the synthesis of Al2O3 nanoparticles embedded in a Polyaniline (PANI) matrix for the fabrication of Al2O3/PANI nanocomposite films. The electrodeposition method was employed to deposit these films onto ITO-glass substrates, with concentrations ranging from 5 % to 20 %. The optical properties of the nanocomposites were analyzed using UV–Vis spectroscopy, allowing the determination of the refractive index and absorption coefficients. In addition, the Scherrer equation was used to calculate the average crystallite size, providing insight into the microscopic, ordered regions within the material. With increasing nanoparticle concentration in PANI-Al2O3 nanocomposites, Tauc plots revealed an increase in energy band gaps from 3.70 eV to 3.85 eV. Additionally, optical bandgap energies increased in PANI- Al2O3 nanocomposites, while electrical conductivities decreased with higher Al2O3 NPs content. Incorporation of Al2O3 NPs reduced the degree of conjugated π-bonds in PANI and disrupted the ordered structure of polymer chains. Moreover, the SEM analysis confirmed that the nanocomposite films had a dense, fiber-like structure. Further analysis of FTIR and XRD data revealed interactions between Al2O3 nanoparticles and PANI chains. At lower concentrations, minimal interaction was observed, while higher concentrations resulted in enhanced molecular interactions, leading to improved chain stretching, molecular packing, and larger crystallite sizes. As a result of Al2O3 nanoparticle incorporation, the nanocomposites exhibited conductivity values ranging from 0.12 to 0.02 S cm−1. These engineered nanocomposite films, characterized by high crystallinity, varied electrical conductivities, and controlled band gaps, show promising potential as active components in next-generation optoelectronic devices.

THE MAGNETIC FIELD ON THE BIOCONVECTION FLOW OF NEPCM IN A Z-SHAPED CAVITY CONTAINING THREE CIRCULAR CYLINDERS

This work adopts an incompressible smoothed particle hydrodynamics (ISPH) method for handling the bioconvection flow of nanoparticle-enhanced phase change materials (NEPCM) inside a Z-shaped containing three circular cylinders and oxytactic microorganisms. The fractional time derivative of a system of controlling equations is solved by the ISPH method. The influences of magnetic field on thermosolutal convection of NEPCM in Z-shaped cavity. The mesh-free nature of the ISPH method helps in simulating the nanofluid flow in complex geometries. The Z-shaped cavity was chosen in this work for bioconvection flow because of its uses in semiconductors in solar cells, electronic devices, biomedicine, and thermal batteries. The bioconvection flow and heat transfer of the embedded circular cylinders are significant in heat exchangers and renewable energies. The scales of physical parameters are bioconvection Rayleigh number Rab=1−1000, Lewis number Le=1−20, Hartmann number Ha=0−80, fractional-time derivative α=0.9−1, Rayleigh number Ra=103−106, the radius of embedded circular cylinders Rc=0.05−0.2, and nanoparticles’ parameter ϕ=0−0.15. The results introduced the importance of Rab in enhancing the distributions of oxytactic microorganisms, and oxygen concentrations as well as the intensity of the velocity field. The size of embedded circular cylinders is effective in adjusting the distributions of oxytactic microorganisms, oxygen concentration, and temperature inside a Z-shaped cavity. The maximum velocity field decreases by 86.79% as nanoparticle concentration increases from 0% to 15% due to the resulting high viscosity of the suspension fluid. An expanded radius of embedded circular cylinders improves the values of Nu‾ and Sh‾. This research provides crucial insights into optimizing thermal management and efficiency across diverse technological applications, from electronics to renewable energy and biomedical devices.

Bio-inspired stretchable and self-healable nanocomposite gelatin hydrogel with low silica nanoparticle content and brilliant angle/strain-independent structural colors

Stretchable and self-healable structural-colored nanocomposite gelatin hydrogel with photonic structure of random dense/loose regions of non-close-packed silica nanoparticles (SiO2 NPs) is developed via convenient and scalable polymer-mediated assembly. The formation of the special photonic structure with overall low SiO2 NP content is characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The small-angle X-ray scattering test indicates the existence of short-range order, which is consistent with the TEM and SEM results. The dense photonic structure consisting of SiO2 NP chains and domains, and the loose structure consisting of abundant solitary SiO2 NPs, accounts for pronounced and uniform structural colors via combined effects of coherent scattering of light by dense structure, and Mie scattering of solitary NPs. These structural colors are independent of viewing angles and large mechanical strains. The dynamic physical and chemical bonding of the gelatin hydrogel network matrix enables self-healing functions and good deformability. Moreover, salt treatment of the structural-colored gelatin hydrogel networks enhances physical crosslinking and the mechanical strength of the hydrogel. The resilient, flexible and self-healable structural-colored nanocomposite hydrogel with low SiO2 NP content has great potential in wearable photonics, cosmetics, and various other color-related fields. This work also sheds light on enhancing non-iridescent structural colors through advanced photonic design.

An In-Vitro Study of the Cytotoxicity of Chitosan Nanoparticles-Containing Orthodontic Primer

Background: Demineralization is an anticipated side effect of fixed orthodontic treatment. Incorporating antimicrobial compounds into orthodontic adhesive material may be an effective method for averting white spots. The objective of this study was to evaluate the cytotoxicity of an orthodontic primer modified with varying quantities of chitosan nanoparticles. Materials and methods: 0%, 1%, 5%, and 10% concentrations of Chitosan nanoparticles have been combined with Transbond TM XT primer. Three discs of eight millimeters in diameter and two millimeters in thickness were constructed for each group, for a total of twelve discs. Results: included the application of scanning electron microscopy (SEM) and X-ray diffraction (XRD) to confirm the Nano powder's properties. The data was statistically examined using one-way analysis of variance (ANOVA), and the results indicated statistically non-significant differences between groups (p˃0.05). In conclusion, the addition of chitosan nanoparticles to the orthodontic adhesive system's primer exhibited an acceptable level of cytotoxicity and was within the appropriate ISO limits (70% cell viability).

Numerical heat transfer analysis of bio convective flow of non-Newtonian nanofluid with Darcy-Forchheimer effect over a curved stretching surface

The main aim of this study is to investigate the behavior of bio-convective flow of 2nd grade micropolar nanofluid with Darcy-Forchheimer law over a curved porous stretching surface. The fluid flow analysis includes novel aspects such as the nonuniform heat source/sink, Joule heating, magnetic field, chemical reaction, and thermal radiation. Furthermore, the boundary of the stretching surface is acquired the stratification conditions. A suitable conversion method is employed to transform the flow model into a collection of ordinary differential equations, characterized by their nonlinearity. The bvp4c technique on the MATLAB is utilized to acquire numerical solutions for this set of nonlinear equations. The characteristics of various influential parameters on the velocity, temperature, concentration, and microorganism density profiles are observed and discussed. In the present problem, it is observed that by the growth of micropolar parameter enhances the angular fluid velocity. Moreover, larger values of the magnetic parameter, Darcy number, and porosity parameter result in a decrease in the fluid’s linear velocity. The temperature profile exhibits a decreasing pattern with the elevation thermal stratification parameter, while the opposite trend shows by the increment of the radiation parameter and Eckert number. Additionally, the concentration of nanoparticles decreases as the Schmidt number and Brownian motion parameter increases.

Impacts of thermal conductivity and viscosity variation parameters on non-Newtonian nanofluid flow with mixed convection and chemical reaction features

Impacts of thermal conductivity and viscosity variation parameters on non-Newtonian nanofluid flow with mixed convection and chemical reaction features

Effect of using a ZnO-TiO2/water hybrid nanofluid on heat transfer performance and pressure drop in a flat tube with louvered finned heat exchanger

AbstractThis study used an experimental setup consisting of a flat tube with a louvered finned crossflow configuration to examine the effects of utilizing a ZnO-TiO2-water hybrid nanofluid on heat transfer rate, heat transfer coefficient, Nusselt number, and pressure drop. The studies were carried out under laminar flow conditions (200 &lt; Re &lt; 800), at four different temperatures (50, 60, 70, 80 °C), four different volume concentrations of nanoparticles (0.025, 0.05, 0.1, 0.2%), and three different volume flow rates (4, 6, 8 LPM). The findings were compared with pure water (0%). The results indicate that using hybrid nanofluid improves the heat transfer performance and increases pressure loss in comparison with pure water. When comparing hybrid nanofluid to pure water, the largest increases in heat transfer rate, heat transfer coefficient, Nusselt number, and pressure drop were 87.8%, 21.7%, 26.4%, and 10%, respectively. In addition, it was found that, up to a specific value (0.05%), increasing the nanoparticle volume concentration enhanced the heat transfer rate, heat transfer coefficient and Nusselt number, but which began to decrease on increasing the concentration past this value. Therefore, it was concluded that nanoparticle volume concentrations greater than 0.05% negatively affect heat transfer under the current operating conditions. The maximum heat transfer rate, heat transfer coefficient, and Nusselt number were obtained under the conditions of an 8 LPM volume flow rate, 80 °C inlet temperature, and 0.05% volume concentration.

Efficient chromium removal from leather industrial wastewater in batch experimental study: Green synthesis and characterization of zinc oxide nanoparticles using Ficus benghalensis extracts

The urgent need to address the severe environmental risk posed by chromium-contaminated industrial wastewater necessitates the development of eco-friendly cleanup methodologies. Utilizing the Ficus benghalensis plant extracts, the present study aims to develop green zinc oxide nanoparticles for the removal of Cr metal ions from wastewater. The leaves of Ficus benghalensis, often known as the banyan tree, were used to extract a solution for synthesizing ZnO NPs. These nanoparticles were developed with the goal of efficiently eliminating chromium (Cr) from industrial effluents. Batch studies were carried out to assess the efficiency of these synthesized ZnO NPs in treating leather industrial effluent, with aiming for optimal chromium removal. This involved measuring the nanoparticles' capacity to adsorb Cr ions from wastewater samples by comparing chromium levels before and after treatment. Removal efficiency for Cr was estimated through the batches such as optimization of pH, contact time, initial Cr concentration and sorbent dose of ZnO NPs were of the batches. These synthesized ZnO NPs were found to be successful in lowering chromium levels in wastewater to meet permissible limit. The nanoparticles exhibited their highest absorption capacity, reaching 94 % (46 mg/g) at pH 4, with a contact time of 7 hours with the optimum sorbent dose of 0.6 g/L. Hence, the excellent adsorption capabilities of these nanoparticles, together with their environmentally benign manufacturing technique, provide a long-term and efficient solution for chromium-contaminated wastewater treatment. Its novel nature has the potential to significantly improve the safety and cleanliness of water ecosystems, protecting the both i.e. human health and the environment.

Comprehensive Analysis of Curcumin Zinc Oxide Nanoparticles, Synthesis, Characterization, and Cytogenotoxic Profiling.

Curcumin from turmeric (Curcuma longa) has traditionally been used due to its pharmacological properties, such as anticancer, anti-inflammatory, cholesterol-lowering, and antioxidant activities, but has had limitations in use due to low bioavailability. Nanoparticles have protuberant efficacies to diagnose or cure a variety of diseases, including tumors, by fine-tuning their size, structure, and physicochemical characteristics. This study aims to develop a new dosage form of curcumin nanoparticles with zinc oxide to enhance its therapeutic efficacy against cancer and cause no damage to genetics. Curcumin zinc oxide nanoparticles were prepared and characterized by using a Zeta sizer, ultraviolet (UV)-spectrophotometer, scanning electron microscope (SEM), and Fourier transform infrared (FTIR) spectroscopy. Different concentrations range from 40 to 0.078 μg/mL, and these nanoparticles were evaluated for their anticancer activity by colorimetric analysis (MTT assay) on normal (Vero) and cancerous cell lines (MCF-7) and genotoxicity by the comet assay. The spherical-shaped curcumin zinc oxide nanoparticles of 189 nm size were prepared with characteristic functional groups. The selectivity index of curcumin zinc oxide nanoparticles, calculated from IC50 values, is 4.60 > 2.0, showing anticancer potential comparable to tamoxifen. The genetic damage index of the highest concentration (40 μg/mL) of curcumin zinc oxide nanoparticles was 0.08, with a percent fragmentation of 8%. The results suggest that nanoparticles of curcumin zinc oxide produced better anticancer effects and did not cause any significant damage to the DNA. Consequently, further research is required to ensure the development of a safe and quality dosage form of nanoparticles for proper utilization.

Electrochemical Hg2+ sensor based on electrospun cellulose acetate nanofibers doped with Ag nanoparticles

Mercury (Hg) sensors are critical for environmental monitoring, industrial processes, and public health. They are designed to measure the presence and concentration of mercury ions (Hg2+) in various matrices, including air, water, soil, and biological samples. Mercury in the environment raises concerns due to its toxicity and potential for bioaccumulation. Therefore, this work aims to develop an improved, eco-friendly mercury sensor to address the evolving need for monitoring and control of mercury. The electrochemical sensor for reported here is based on the ability of silver (Ag) to catalyze the reduction of the mercury species Hg2+ to elemental mercury (Hg0), forming an Ag/Hg amalgam. To optimize this sensor, the concentration of silver nanoparticles (AgNPs) on modified nanofibers is determined using differential pulse voltammetry (DPV). Morphological studies and chemical characterization reveal a fiber thickness ranging from 250 to 450 nm and characteristic functional groups, respectively. The sensoŕs analytical performance for detecting Hg2+ concentrations is evaluated through cyclic voltammetry (CV) and DPV in 0.1 M potassium chloride as a supporting electrolyte. The sensor’s detection limit (LOD) for Hg2+ was 0.43 μg/L, with a sensitivity of 0.33 mA/μg/L. In conclusion, the electrochemical sensor exhibits sensitivity and selectivity for Hg2+ detection in the presence of other interfering metal ions, along with eco-friendly and cost-effective features, making it a reliable and practical tool for detecting Hg2+ concentration in water samples.

Optimization and heat transfer analysis for MHD radiative natural convective flow of hybrid nanofluid within a partially heated cavity

The current study consists of optimization and heat transfer analysis for magnetohydrodynamic (MHD) radiative-natural convective flow of hybrid nanofluid (mixture of silver and copper nanoparticles with ethylene glycol (base fluid)) saturated inside the partially heated isosceles triangular cavity. Additionally, the current analysis investigates the distraction of available energy during thermal mixing and flow friction through local entropy generation. The conservation laws of total mass, momentum, and energy balance equations have been utilized to govern the physical flow problem. After eradicating the pressure terms in the governing partial differential equations (PDEs) via the penalty technique, the Galerkin finite element method (FEM) with the Newton-Raphson technique has been utilized to solve it. The outcomes established that the concentration of silver nanoparticles, as compared to copper nanoparticles, gives better energy transport. An increase in the concentration of nano-particles from ( ϕ 1 = ϕ 2 = 0 ) to ( ϕ 1 = ϕ 2 = 0.1 ) increased the intensity of streamlines from ψ max = 1.5 to ψ max = 4 and energy transmit rate increases by 57.4 % . The influence of thermal radiation decreased the fluid flow friction or local entropy via fluid flow.

One-Step Preparation Method and Rapid Detection Implementation Scheme for Simple Magnetic Tagging Materials

With the widespread application of tagging materials, existing chemical tagging materials exhibit limitations in stability and detection under field conditions. This study introduces a novel magnetic detection scheme. Hydrophilic material-modified Fe3O4 nanoparticles (COOH-PEG@Fe3O4 NPs) were synthesized using the co-precipitation technique. The content of Fe3O4 nanoparticles in the magnetic tagging liquid can reach up to 10 wt% and remain stable in an aqueous phase system for seven days. This research details the preparation process, the characterization methods (IR, 1HNMR, EDX, XRD, SEM, TEM, VSM, DLS), and the performance effects of the materials in magnetic tagging. Experimental results indicate that COOH-PEG@Fe3O4 NPs exhibit high remanence intensity (Br = 1.75 emu/g) and considerable stability, making it possible to quickly detect tagged liquids in the field using portable flux meters and optical pump magnetometers. This study provides new insights into the design and application of magnetic tagging materials, making it particularly suitable for long-term tagging and convenient detection in field scenarios.

Radioprotective effect of polyvinylpyrrolidone modified selenium nanoparticles and its antioxidation mechanism in vitro and in vivo.

Polyvinylpyrrolidone (PVP) is a commonly used biomedical polymer material with good water solubility, biocompatibility, low immunogenicity, and low toxicity. The aim of this study is to investigate the antioxidant mechanism and clinical potential of PVP modified selenium nanoparticles (PVP-Se NPs) as a new radioprotective agent. A laser particle size analyzer and transmission electron microscope were used to characterize PVP-Se nanoparticles prepared by chemical reduction. Human umbilical vein endothelial cells (HUVECs) were used to evaluate the radiation protective effects of PVP-Se NPs. SD rats were employed as an in vivo model to identify the most effective concentration of PVP-Se NPs and assess their potential radioprotective properties. Western blot (WB) was used to detect the expression of nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling proteins in human umbilical vein endothelial cells (HUVECs) and rat liver and kidney tissues. PVP-Se NPs could reduce the oxidative stress injury and inflammatory response caused by X-ray irradiation in HUVECs and rats, and inhibit cell apoptosis by modulating NF-κB and MAPK signaling pathways. PVP-Se NPs could increase HUVECs viability, reduce apoptosis, inhibit inflammatory factors IL-1β, IL-6 and TNF-α, improve the survival rate of rats, promote antioxidant enzyme activities in cells and rats, reduce malondialdehyde concentration in serum, and reduce the expression of inflammatory factors such as IL-1β, IL-6 and TNF-α in cell supernatant and liver and kidney tissues. PVP-Se NPs could significantly reduce the phosphorylation levels of NF-κB and MAPK pathway-associated proteins in HUVECs and rat liver and kidney tissues (p < 0.05). PVP-Se NPs can protect against radiation-induced oxidative damage by modulating NF-kB and MAPK pathways, providing a theoretical basis and experimental data for their use as an effective radioprotective agent.

Enhanced DeNOx catalysis: Induction-heating-catalysis-ready 3D stable Ni supported metal combinations

Catalysis plays a critical role in the quest for sustainable automotive technology, particularly in reducing harmful emissions from vehicles. The catalysts are required to operate efficiently in dynamic and challenging environments. This study introduces innovative deNOx catalysts featuring nominal concentrations of Pd and Re nanoparticles doped on a NiMo support. The best-performing fabricated catalyst demonstrated impressive 95 % NOx conversion at 250°C, significantly outperforming traditional systems and reducing ammonia slip. Integrating nickel as the support material was strategic choice to leverage novel induction heating-assisted catalytic system. This approach is particularly advantageous when starting cold engine, reducing harmful NOx emissions when the catalyst is not fully operational. Functional monolith model of car converter catalyst with similar composition was also developed. This research presents novel catalyst solution that achieves high deNOx efficiency while offering a cost-effective alternative to traditional methods. Induction heating enhances the catalyst's performance, particularly at lower temperatures, showcasing significant improvement over conventional thermal methods.