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Nanotechnology, with its potential to manipulate matter at nanometric scales, has revolutionized multiple sectors. Among various nanomaterials, zinc oxide nanoparticles (ZnO NPs) are prominent due to their unique physicochemical properties, attributed to their small size and crystallinity. ZnO NPs are widely used in biomedicine due to their adaptability, biocompatibility, low toxicity, and cost-effectiveness. However, conventional fabrication methods, which often involve harmful reducing chemicals, pose significant environmental and health risks. In recent years, the use of biological extracts in the synthesis of ZnO NPs has gained favor as a more sustainable and eco-friendly approach. Plant-based phyto-extracts, in particular, are highly effective for this purpose. These extracts act as bio-reducers, stabilizers, and capping agents, influencing the size, surface properties, and overall architecture of the ZnO NPs. This green synthesis method not only reduces environmental impact but also enhances the inherent biofunctionalities of ZnO NPs, making them highly suitable for various biomedical applications. Greenly-designed ZnO NPs exhibit a range of pharmacological benefits, including antimicrobial effects against bacterial and fungal pathogens, antioxidative properties against reactive oxygen species (ROS), anticancer activities against abnormal cell proliferation, antidiabetic and anti-inflammatory properties. These attributes make greenly-designed ZnO NPs promising candidates for advancing healthcare technologies, combining sustainability with potent therapeutic potential. [Display omitted] • Nanotechnology holds functions in the diverse sectors. • ZnO NPs (zinc oxide nanoparticles) has peculiar physiochemical traits. • ZnO NPs are suitable for biomedical applications. • Phyto-extract adopted ZnO NP's fabrication is eco-friendly. • Greenly-designed ZnO NPs exhibits versatile pharmacological traits. [ABSTRACT FROM AUTHOR]

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This work aims to determine the effect of stresses caused by dislocation networks placed at the interface of a semiconductor heterostructure of the thin GaAs/Si system. In this case, we use a mathematical modeling by Fourier series expansion to numerically simulate the stresses for the two cases of isotropic and anisotropic elasticity in order to predict the mechanical behavior of the heterostructure in the presence of interfacial dislocations while respecting well-defined stress boundary conditions. The elastic stress relaxation is reached for a layer thickness threshold of the GaAs deposit on the Si substrate not exceeding 5 nm. [ABSTRACT FROM AUTHOR]

To decrease the light scattering caused by birefringence of the tetragonal phase of dental Yttria-Stabilized Zirconia (YSZ), two main strategies are followed: 1) increasing Y 2 O 3 content to have a larger amount of non-birefringent cubic phase or 2) decreasing grain size below 100 nm to reduce their scattering coefficient. Both strategies might affect mechanical properties and aging resistance. This study shows that increasing the stabilizer content enhances both translucency and aging resistance, at the expense of mechanical properties. Nanometric-sized YSZ show, instead, very interesting compromise. Nanometric-sized zirconia stabilized with 3 mol.% of Y 2 O 3 possesses high strength and toughness (above 1600 MPa and 3.3 MPa m1/2), aging resistance and translucency, thanks to its fully-stabilized tetragonal nano-grains. Nanometric-sized zirconia stabilized with 1.5 mol.% of Y 2 O 3 has the best mechanical performances (strength above 1500 MPa and toughness of 4.8 MPa m1/2), still showing aging resistance and intermediate opacity. These results highlight the interest of moving towards Yttria-containing transformable tetragonal nano-ceramics for dental applications. [Display omitted] [ABSTRACT FROM AUTHOR]

We model the dielectric function of aluminum (Al). The modeling has been performed on Al in bulk and nanometric states. First, we will model the experimental measurements of the dielectric constant as a function of the pulsation ω by appropriate mathematical functions in an explicit way. In the second part, we will highlight the contributions due to intraband and interband electronic transitions. In the last part, we model the dielectric constant of this metal in the nanometric state using several complex theoretical models such as the Drude Lorentz theory and the Drude two-point critical model. We shall comment on which model fits the experimental dielectric function best. [ABSTRACT FROM AUTHOR]

The research activities are oriented towards elaborating and characterizing nano- sized powders by powder metallurgy technologies based on wet milling in a planetary mill. For the elaboration of the TiB2 powders, a wet milling regime of initial powders was used up to nano size with the following parameters: milling technology by collision, milling times, rotational speed. The characterization of the TiB2 material will include particle size distribution analysis. EDXS and SEM analysis were used to study the structural evolution of the powder after ball milling. The mechanical milling technology, by its milling regimes, proved to be very efficient, obtaining a reduction of the titanium diboride powders particle size up to 50% compared to the initial unmilled powders. [ABSTRACT FROM AUTHOR]

Prosthetic contamination and biofilm formation continue to plague implanted materials. With increasing resistance to traditional antibiotic regimens, alternative approaches to preventing bacterial adhesion and biofilm formation have focused on the physiochemical properties of the prosthetics. Roughness, topography, hydrophobicity, porosity, charge, stiffness, and surface area all influence the processes of adhesion and colonization leading to biofilm formation. In this review, we discuss the physiochemical properties of solid and porous prosthetic materials that influence biofilm formation at the nanometric scale. [ABSTRACT FROM AUTHOR]

The 1:2 chelation behavior of the cimetidine (cim) anti-ulcer drug towards three metal ions of tungsten (VI), silicon(IV) and hafnium (IV) was investigated. The synthesis and characterizations of [M(cim)2].xCl2 (where M = W, Si or Hf; x = 2 for Si or Hf and x = 3 for W) were discussed. The cim ligand acts as tetradentate N(3) imidazole, S(8) thioether, N(11) secondary amine and the N-nitrile group seems to be involved in the complexation. The microanalytical, magnetic, conductance, FTIR, UV-visible, XRD, 1H-NMR spectral studies, were employed for the characterization. The inhibition activity of drug ligand and its metal ion complexes was evaluated towards different types of bacteria and fungi through in vitro antimicrobial activities. The antitumor activity of silicon(IV) complex is straightened towards human liver carcinoma (HepG-2) cell lines. [ABSTRACT FROM AUTHOR]

A nanometric HMX-based polymer-bonded explosive (PBX) is prepared by using the solution-water slurry technique. The resultant PBX is composed of 94% of HMX, 5% of fluororubber Viton, and 1% of wax. The properties of the nanometric HMX-based PBX, such as sensitivity and compressive performance, are comprehensively researched. The results show significant improvement for the nanometric HMX-based PBX as compared to the micron-sized HMX-based PBX. The friction sensitivity, impact sensitivity, and shock sensitivity of the nanometric HMX-based PBX are obviously lower by 30, 48, and 24%, respectively. Moreover, the compressive strength and strain of the nanometric HMX-based PBX are significantly higher by 273 and 33%, respectively. Thus, both the safety and mechanical resistibility of the PBX will significantly benefit from using nanometric HMX. [ABSTRACT FROM AUTHOR]

The evolution of ultra precision finishing processes due to the continuous demand of stringent functional and technological requirement of the components has led to the emergence and development of the non-conventional abrasive flow finishing (AFF) process. This could be attributed to the need for relaxation of tool limitations: precise finishing of complex geometries and internal passages in typical industrial components. Herein, the abrasive laden polymer conforms onto the work piece geometry due to its flow characteristics overcoming the shape limitations inherent in conventional finishing processes. The paper describes nanometric surface finishing of typical prosthetic implants and an extrusion die used in bio-medical and pharmaceutical industries, respectively. Finishing and deburring of a propeller and a shuttle valve used in aerospace applications are also discussed. The study highlights the possibility of successful extension and implementation of AFF process in simultaneous ultra precision finishing applications of industrial components. The versatility, functional, and stochastic aspect of the developed AFF system in surface finishing of ferrous and non-ferrous components is also emphasized. [ABSTRACT FROM AUTHOR]

The importance of crystal interfaces in the assessment of the effects of elastic fields Eshelby et al. (Acta Meta 1:251-259, ) for nanoscale multilayer materials is a topical area that has been the focus of many researchers. This work focuses on the characterization and modeling of interfacial defects on both microscopic and macroscopic scales. From a design perspective, considering such elastic fields has become a critical element in the development of multilayer's in the industry due to their effect on the properties of materials. The description of elastic fields associated with misfit dislocations in a multilayer involving hetero fields is possible thanks to the inversion of a single set of linear equations. Thus, the aim of this investigation is to evaluate the effects of elastic fields at the level of crystal interfaces for a nanoscale three-layer material under the effect of two-way networks of unidirectional dislocations. These are placed at interfaces accommodating a parametric mismatch which accounts for the particular anisotropic elasticity for each crystal. [ABSTRACT FROM AUTHOR]

The increasing technology node scaling makes VLSI devices extremely vulnerable to Single Event Effects (SEEs) induced by highly charged particles such as heavy ions, increasing the sensitivity to Single Event Transients (SETs). In this paper, we describe a new methodology combining an analytical and oriented model for analyzing the sensitivity of SET nanometric technologies. The paper includes radiation test experiments performed on Flash-based FPGAs using heavy ions radiation beam. Experimental results are detailed and commented demonstrating the effective mitigation capabilities thanks to the adoption of the developed model. [ABSTRACT FROM AUTHOR]

Aggressive miniaturization has led to severe performance and signal integrity issues in copper-based interconnects in the nanometric regime. As a consequence, development of a proper analytical model for such interconnects is extremely important. In this work, an ABCD parameter matrix-based model is presented for fast and accurate estimation of crosstalk delay and noise for identically coupled copper-based nanointerconnect systems. Using the proposed model, the crosstalk delay and noise are estimated in copper based nanointerconnects for intermediate and global interconnects at the future integrated circuit technology nodes of 21 and 15 nm, respectively. Proposed model has been compared with SPICE and it is found that this model is almost 100% accurate as SPICE with respect to both the crosstalk delay as well as noise. Moreover, this model is as much as ~ 63 and ~ 155 times faster, respectively. From the crosstalk delay and noise analysis of unrepeated interconnects, it is observed that both delay and noise contribution will increase in scaled technology nodes. The same trend is observed also for the repeated interconnects. Also more number of repeaters and higher repeater sizes will be needed for delay minimization as we scale deeper. So as far as crosstalk induced effects are concerned, the copper interconnects will face a huge challenge to overcome in nanometer technology nodes. [ABSTRACT FROM AUTHOR]

Large-scale coarse grained molecular dynamics simulations were performed to investigate the self-assemblies of Cetyltrimethylammonium Bromide spherical micelle and the solubilization of four cyclic compounds; pyrrole, aniline, thiophene and cyclohexane within the nanometric micelle. Our results showed that solubilizates with lower polarity are located in the inner regions of micelle and materials with higher polarity are located at the outer areas of micelle and near to the surface. We observed that at low solubilizate content, these compounds are predominantly solubilized in a definite zone in the micelle and this does not significantly change micellar size and shape. With increasing of solubilizates content the location of solubilization is extended from one region to several regions into the micelle and the micelle is subjected to change in size and shape. Our findings are in good conformity with experimental results. It has also been deduced that micelle formation time is crucially bounded to solubilization stage. [ABSTRACT FROM AUTHOR]

Aluminum is used as a metal fuel in energetic materials for the improvement of propulsion performance and density. Both nano-sized and micrometer-sized activated powders represent valuable options in order to improve metal combustion properties, each possessing advantages and drawbacks. These ingredients bear peculiar properties (namely, higher specific surface, coatings, or surface characteristics) which generate high mixing viscosity once suspended in a polymer as well as altered mechanical properties of the final product. Four different powders dispersed in a polymer binder are taken into consideration and the evolution of viscosity in time during the curing process is investigated. The suspending medium is represented by a mixture of hydroxyl-terminated polybutadiene (HTPB), isophorone diisocyanate (IPDI) and dioctyl adipate (DOA). Viscosity was measured for 5 h on samples under isothermal curing at 60 °C. Non-isothermal DSC kinetic analyses were also performed using the Kissinger method. It was found that, for the test conditions, a size reduction of metal particles slowed down the increment rate of curing viscosity while some peculiar coatings, such as fatty acids, introduced opposite trends. [ABSTRACT FROM AUTHOR]

Abstract: The effect of the redox pair electrolyte in the structural, electrochemical and capacitive properties of micrometric and nanometric PEDOT films have been examined. The thickness of the films has been found to play a key role on the capacitive properties, outstanding electrochemical properties being achieved at the nanometric scale. Electrochemical and capacitive properties were extensively investigated using cyclic voltammetry, recurrent galvanostatic pulse, chronopotentiometry and electrochemical impedance spectroscopy techniques. Results evidenced that nanometric PEDOT films exhibit very high electrochemical stabilities and excellent specific capacitances (∼185Fg−1), the latter being preserved in ∼94% after 2000 cycles in a -containing solution. Morphological studies revealed that the electrochemical and capacitive properties of PEDOT films are significantly influenced by their porosity, this property being relatively unaffected by the redox pair. The overall results allowed us to conclude that nanometric PEDOT films in presence of are promising candidates to be employed as supercapacitors. [Copyright &y& Elsevier]

Ag-sheathed (Bi1.6Pb0.4)Sr2Ca2Cu3O10(Bi-2223) high temperature superconductor tapes with 0.1 wt% nano Cr2O3 were fabricated using the powder-in-tube method. The effects of intermediate rolling and sintering temperature on the transport critical current density (Jc) under self-field and applied magnetic field were studied. The X-ray patterns showed a dominant Bi-2223 phase (~80%). A decrease in Jc in applied magnetic field, parallel or perpendicular to the sample wide surface was observed for all tapes. Intermediate rolling improved the self-field Jc(T=77 K) of the tapes by 25%. Both Jc versus applied field curves and normalized pinning force density Fp/Fpmax versus applied field curves showed that the pinning strength was significantly enhanced with thermo-mechanical treatments. SEM micrographs showed improvements in the grain alignment of tapes with intermediate rolling. Enhancement in Jc was observed in the nano Cr2O3 added tapes. [ABSTRACT FROM AUTHOR]

The effects of nanoroughness and chemical composition on the contact and sliding angles on hydrophobic surfaces were studied theoretically and experimentally. A theoretical model based on forces developed at the contact area between a liquid drop and hydrophobic smooth or nanoroughened surface was developed and compared with the existing models, which are based on forces developed at the periphery between the drop and the solid surface. The contact area based model gives rise to an interfacial adhesion strength parameter that better describes the drop-sliding phenomenon. Consequently, relationships were derived describing the dependence between the interfacial adhesion strength of the liquid drop to the surface of a given composition, the mass of the drop, the measured contact angles and the sliding angle. For a given surface chemistry, the sliding angle on a nanometric roughened surface can be predicted based on measurements of contact angles and the sliding angle on the respective smooth surface. Various hydrophobic coatings having different surface nanoroughnesses were prepared and, subsequently, contact angles and sliding angles on them as a function of drop volume were measured. The validity of the proposed model was investigated and compared with the existing models and the proposed model demonstrated good agreement with experimental results. [ABSTRACT FROM AUTHOR]

The present paper deals with the preparation of nanometric yttria powders. A sol–gel method has been adopted to synthesize a precursor gel which, after being heated, leads to Y2O3. Two main parameters are taken into account: the nature of the chelating agent and the [chelating agent]/[Y] relative concentration. The influence of these parameters on the composition and crystallization state of the precursor gel has been studied in the first part and on the grain morphologies of the resulting yttria powder in the second part. It has been shown that, depending on the chelating agent, nanometric powders presenting either needles, platelets or spherical shapes can actually be obtained at 800°C or 1100°C. [Copyright &y& Elsevier]

Thin films of titanium oxides TiOx (x=0.7…2) can be produced by DC reactive magnetron sputtering with O2 and/or H2O as a reactive gas. In this work we investigate the deposition of nanometric multilayers and thin films of modulated composition. Samples are characterized by electrical resistivity measurements, optical measurements, X-ray diffraction and atomic force microscopy. The influence of the sputtering parameters on the morphology and on the electrical properties of the multilayers is reported. The analysis of the electrical and optical properties of the TiO2–TiOx multilayer system will contribute to a better understanding of the doping mechanism of nano-crystalline titanium dioxide by the grain boundaries. [Copyright &y& Elsevier]