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The nanoparticles are frequently used in biomedical science for the treatment of diseases like cancer and these nanoparticles are injected in blood which is transported in the cardiovascular system on the principle of peristalsis. This study elaborates the effects of Lorentz force and joule heating on the peristaltic flow of copper and iron oxide suspended blood based nanofluid in a complex wavy non-uniform curved channel. The Brinkman model is utilized for the temperature dependent viscosity and thermal conductivity. The problem is formulated using the fundamental laws in terms of coupled partial differential equations which are simplified using the creeping flow phenomenon. The graphical results for velocity, temperature, streamlines, and axial pressure are simulated numerically. The concluded observations deduce that the solid volume fraction of nanoparticles reduces the velocity and enhance the pressure gradient and accumulation of trapping bolus in the upper half of the curved channel is noticed for temperature dependent viscosity.

As part of the growing evolution in nanotechnology and thermal sciences, nanoparticles are considered as an alternative solution for the energy depletion due to their ultra-high thermal effectives. Nanofluids reflect inclusive and broad-spectrum significances in engineering, industrial and bio-engineering like power plants, energy source, air conditioning systems, surface coatings, evaporators, power consumptions, nano-medicine, cancer treatment, etc. The present study describes the bio-convective peristaltic flow of a third-grade nanofluid in a tapered asymmetric channel. Basic conservation laws of mass, momentum, energy, and concentration as well as the microorganism diffusion equation are utilized to model the problem. The simplified form of the modeled expressions is accounted with long wavelength assumptions. For solving the resulting coupled and nonlinear equations, a well-known numerical method implicit finite difference scheme has been utilized. The graphical results describe the velocity, temperature and concentration profiles, and the density of motile microorganisms at the nanoscale. Furthermore, microorganism concentration lines are analyzed., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Zinc is an essential trace metal and its concentration above 4ppm reduces the aesthetic value of water. This study explores the possibility of using functionalized nanohybrids as Zn(II) ion scavengers from aqueous solution. Functionalized nanohybrids were synthesized by the attachment of thiosemicarbazide to silica. The material was characterized by TGA, SEM, FTIR, EDX, and BET analysis, which revealed ligand bonding to silica. The functionalized silica was employed as Zn(II) ion extractant in batch experiments and removed about 94.5% of the Zn(II) ions at pH 7, near zero point charge (6.5) in 30 min. Kinetics investigations revealed that zinc adsorption follows an intra particle diffusion mechanism and first-order kinetics (K = 0.1020 min -1 ). The data were fitted to Freundlich, Dubinin-Radushkevich, and Langmuir models and useful ion exchange parameters were determined. The impact of co-existing ions on Zn(II) ion sequestration was also studied and it was found that the adsorbent can be used for selective removal of zinc with various ions in the matrix. Quantum mechanical investigations revealed that the Zn(II) ion adsorption on ZnBS1 is more favorable, having higher binding energy (BE) (-178.1 kcal/mol) and ∆ H (-169.8), and making tridentate complex with the N and S sites of the chelating ligand. The negative ∆G and BE values suggest highly spontaneous Zn(II) adsorption on the modified silica even at low temperatures.

Hybrid nanofluids are used to enhance therapeutic effects and reduce the side effects in tumour therapy. These nanoparticles are transported nearest to the cancer's tissues under the action of the peristaltic waves generated on the walls of the blood vessel. The motion of hybrid nanoparticles in non-uniform vertical channel having flexible boundaries is numerically elaborated in present study. Poisson equations are used on the basis of electro-osmotic theory to encounter the phenomena of applied electric field on the walls of the channel. Lubrication approach and Debye–Huckel linearization approximations are utilized to obtain the system of coupled ordinary differential equations from the basic conservation laws which are solved by using implicit finite difference scheme which is commonly known as Keller–Box method and MATLAB built in subroutine Bvp5c. The impact of electro-osmotic parameter on all features of flow of nanoparticles observed through several graphs and various tables. The current study is applicable and helpful in the design of micropumps and nanomedicine technologies. [ABSTRACT FROM AUTHOR]

In this experimental approach, we explored the structures, morphologies, phototoxicities, and antibacterial activities of undoped and Mn-doped ceria nanocomposite materials, MnxCe1−xO2. The MnxCe1−xO2 nanocomposites were synthesized by employing a soft chemical route. Our prime focus was on the influence of different factors, both physical and chemical, i.e., the concentration of manganese in the product, size of the nanocomposite, drug dose, and incubation time, on the bacterial strains. Different bacterial strains were selected as experimental biological models of the antibacterial activity of the manganese-doped cerium oxide nanocomposite. In addition to the photodynamic response, the adenocarcinoma cell line (MCF-7) was also studied. Based on cell viability losses and bacterial inhibition analyses, the precise mechanisms of apoptosis or necrosis of 5-ALA/PpIX-exposed MCF-7 cells under 630 nm red lights and under dark conditions were elucidated. It was observed that the undoped nanocomposites had lower cytotoxicities and inhibitions compared with those of the doped nanocomposites towards pathogens. The antibacterial activity and effectiveness for photodynamic therapy were enhanced in the presence of the manganese-doped ceria nanocomposite, which could be attributed to the correlation of the maximum reactive oxygen species generation for targeted toxicity and maximum antioxidant property in bacteria growth inhibition. The optimized cell viability dose and doping concentration will be beneficial for treating cancer and bacterial infections in the future. [ABSTRACT FROM AUTHOR]

The optical properties of the CdO and Pt doped CdO thin films synthesized by sol-gel technique were investigated. The lowest grain size value (81.34 nm) was found to be for CdO thin film. The Pt doped CdO films are transformed to clusters with nanoparticles. The transparency properties of the CdO thin film is changed with Pt doping. The plots of refractive index indicate abnormal and normal dispersion regions. The refractive index values of the CdO thin film are changed with Pt doping. The direct optical band gap values of the films were changed with doping of Pt. The film of 0.5% Pt doped CdO indicates the lowest optical band gap value (2.421 eV). The imaginary parts of the optical conductivity of the CdO and Pt doped CdO thin films are higher than that of the real parts of the optical conductivity. [ABSTRACT FROM AUTHOR]

Abstract: Zinc oxide semiconductor is a promising material for various optoelectronic applications such as visible light and UV detectors. The photoresponse and electrical characterization of the photodiode based nanofibers n-ZnO and p-Si semiconductors have been investigated. The Al/p-Si/n-ZnO/Al diode shows a clear rectifying behavior with a rectification ratio of 2.90×104 at ±4V. The diode exhibits a photoconducting behavior with a ratio I on/off of 60. The photoconducting mechanism of the diode is controlled by the presence of exponential distribution of impurity levels in the forbidden band of ZnO. The obtained results indicate that the Al/p-Si/n-ZnO/Al diode can be used as photodiode in optoelectronic applications. [Copyright &y& Elsevier]

The effect of TiO2 nanoparticles on the photophysical properties of ternary conjugated polymer (CP) blends of poly(9,9-dioctylfluorene-2,7-diyl) (PFO), poly 9,9-dioctylfluorene-alt-benzothiadiazole (F8BT) and poly(2-methoxy-5(2-ethylhexyl)-1,4 -phenylenevinylene (MEH-PPV) thin films was investigated. This ternary blend used a fixed amount of PFO as the donor with MEH-PPV and F8BT in various ratios as the acceptors. The solution-blending method and the spin-coating technique were used to prepare the blends and the thin films, respectively. Through efficient Förster Resonance Energy Transfer (FRET), the desired white emission was achieved with PFO/0.3 wt.% F8BT/0.5 wt.% MEH-PPV ternary blend thin film. Additions of nanoparticles up to 10 wt.% dramatically intensified the white emission which then dimmed at higher contents due to agglomerations. The current density–voltage characteristics of the nanocomposite thin films exhibited dependency on the content and distributions of the nanoparticles. Finally, a possible underlying mechanism for the intensification of emission is proposed. [ABSTRACT FROM AUTHOR]

Empirical Modeling of Zn/ZnO Nanoparticles Decorated/Conjugated with Fotolon (Chlorine e6) Based Photodynamic Therapy towards Liver Cancer Treatment. (e) Obtained post ZnO + Fotolon (chlorine e 6) treatment under exposure of UV lamp light. (e) Obtained significant necrosis when treated with ZnO + Fotolon (Chlorine e 6) under exposure of UV lamp light. [Extracted from the article]

This paper reports on the synthesis of ZnO nanowires (NWs), as well asthe compound nanostructures of nanoparticles (NPs) and nanowires (NWs+NPs) with different coating layers of NPs on the top of NWs and their integration in dye-sensitized solar cells (DSSCs). In compound nanostructures, NWs offer direct electrical pathways for fast electron transfer, and the NPs of ZnOdispread and fill the interstices between the NWs of ZnO, offering a huge surface area for enough dye anchoring and promoting light harvesting. A significant photocurrent density of 2.64 mA/cm2 and energy conversion efficiency of 1.43% was obtained with NWs-based DSSCs. The total solar-to-electric energy conversion efficiency of the NWs+a single layer of NPs was found to be 2.28%, with a short-circuit photocurrent density (JSC) of 3.02 mA/cm2, open-circuit voltage (VOC) of 0.74 V, and a fill factor (FF) of 0.76, which is 60% higher than that of NWs cells and over 165% higher than NWs+a triple layer of NPs-based DSSCs. The improved performance was obtained due to the increased specific surface area for higher dye anchoring and light harvesting of compound nanostructures with NWs+a single layer of NPs. [ABSTRACT FROM AUTHOR]

• Au-TiO 2 nanoparticles conjugated with doxorubicin (DOX) were synthesized for new photodynamic therapy (PDT). • Anatase/rutile phase junction effect combined with plasmonic resonance are amplified in Au- TiO 2 conjugated with DOX. • Au-TiO 2 plays a key role in photocatalytic activity via the development of a new energy bandgap in the composite. • Cancer-cell viability loss of up to 70%. • Empirical modeling was performed for statistical analysis of biotoxicity towards the breast cancer cell line. Au-TiO 2 nanoparticles conjugated with doxorubicin (DOX) were synthesized for new photodynamic therapy (PDT) plans and for comprehensive and reliable treatment of breast cancer-related acute diseases. The anatase/rutile phase junction effect combined with plasmonic resonance is amplified in Au- TiO 2 conjugated with DOX, leading to a synergistic response of PDT. Au-TiO 2 plays a key role in photocatalytic activity via the development of a new energy bandgap in the composite. The capsules of Au-TiO 2 @DOX can readily diffuse into the tumor's vicinity because of the acidic environment of the tissue core, where DOX acts as a photosensitizing agent when Au-TiO 2 is excited by an optimal dose of ultraviolet (UV) light, and it demonstrated that a cancer-cell viability loss of up to 70%. This was confirmed by various analytic techniques: reactive oxygen species (ROS) fluorescence, cell mortality assay, MTT assay, apoptosis detection assay, and membrane integrity assay. Furthermore, empirical modeling was performed for statistical analysis of biotoxicity towards the breast cancer cell line. The results acclaim the targeted photokilling efficacy of Au-TiO 2 @DOX nanocomposites for breast malignancy treatment, as well as in vivo applications, owing to their biocompatible properties for healthy tissues, and as an embattled weapon for breast cancer. After vigilant investigation, it is expected that these ongoing research outcomes will contribute significantly to actual treatment of breast cancer. [ABSTRACT FROM AUTHOR]