Narrow Results

Exploring electrokinetics phenomena in the context of diverse currents and nanoparticle blends introduces the possibility of novel biomedical approaches. This research is aimed at exploring the streaming patterns of electro-magnetized blood infused with titanium dioxide nanoparticles and single-walled carbon nanotubes (SWCNTs) in a squeezed arterial channel under the influence of electroosmosis. The model is deliberated through the imposition of an intense external magnetic field that is aligned perpendicular to the channel, resulting in effects such as Hall and ion-slip currents and Joule warming. The distribution of electric potential within the electric double layer (EDL) is predicted by solving the Poisson–Boltzmann equation. The Runge–Kutta–Fehlberg (RKF45) shooting scheme via bvp4c solver in Mathematica is hired to execute the proposed blood flow model computation. By presenting informative graphs and tables, a study is carried out to comprehend and elucidate the physical effects of crucial factors on flow dynamical features and physical quantities. A statistical analysis is carried out to identify the intricate association of model parameters with physical flow characteristics, enriching the study’s novelty. Some key outcomes are that the blood temperature attenuates with swilling values of Hall and ion slip parameters. The skin friction on the artery’s upper wall is lessened when the electroosmosis parameter gets increase. Expanding volume fraction of nanoparticles results in an elevation of the Nusselt number on the upper wall. In squeezed artery, the streamlines in the blood flow are notably aligned. The study’s findings could contribute to improving drug delivery strategies, diagnostics, medical imaging, patient care, treatment outcomes, design of biomedical devices, such as stents and catheters, and understanding of blood flow behavior in intricate arterial configurations.

To control the emission of SO₂ from flue gas into the atmosphere while considering the capture and collection of greenhouse gas CO₂, the adsorption behavior of a binary mixture of SO₂ and other gases in flue gas (O₂/N₂/H₂O/CO${}_2)$ in (10, 10) carbon nanotube (CNT) was simulated using grand canonical Monte Carlo (GCMC) simulation. The adsorption and separation performance of SO₂ in CNTs with a diameter range of 0.81–1.63 nm for the five-component mixture gas was also analyzed. The findings suggest that the adsorption and separation of SO₂ are primarily influenced by CO₂ (reduction of adsorption capacity by about 50%, separation coefficient of SO₂/CO₂ is lowest) with this effect being more pronounced under high pressure. Meanwhile, it was observed that CNTs with larger pipe diameters exhibit higher SO₂ adsorption capacity, but relatively lower SO₂/CO₂ selectivity and lower stability. On the other hand, CNTs with smaller diameters have relatively lower adsorption capacity for SO₂, but exhibit good selectivity and stability (under different pressure) for SO₂/CO₂. Based on the statistical analysis of SO₂ adsorption capacity and SO₂/CO₂ selectivity, it was determined that (6, 6) CNT with a diameter of 0.81nm can exhibit excellent SO₂ adsorption and separation performance at atmospheric pressure, while appropriate large diameter CNTs should be selected for flue gas treatment under high pressure.

The influence of reinforcement of carbon nanotubes (CNTs) on microstructural features and mechanical properties of thermally sprayed Al₂O₃–3wt.%TiO₂ and WC–20wt.%Co coatings was investigated. Alumina–Titania coatings were deposited by Air Plasma Spraying (APS) and Tungsten Carbide–Cobalt coatings were deposited by High-Velocity Oxy-Fuel (HVOF) spraying process. The coatings obtained with reinforcement of CNTs were characterized to interpret the microstructural changes and also to evaluate the variation in their mechanical properties. The percentage composition of CNTs in both APS and HVOF coatings systems were varied in the order of 2, 4, and 6wt.%. It has been found that homogenous dispersion of carbon nanotubes in the coating systems results in increased microhardness and reduced surface roughness. Also, the microstructural features of the coating systems clearly showed that the coatings are denser with fewer pores due to the presence of CNTs.

Unsteady thin hybrid nanoliquid film flow over a stretchable cylindrical surface is studied with the uniform thickness of hybrid nanoliquid. The combined effects of different nanoparticles like single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs) and copper (Cu) are considered for investigation in the presence of thermocapillarity, magnetic field and thermal radiation. The finite difference technique is applied to solve the governing set of nonlinear equations. Result showed that the hybrid nanoliquid film thinning rate declined with the higher volume fraction of different nanoparticles. The hybrid nanoliquid film thickness enhanced with higher values of radiation parameter and magnetic field. A curve $Z=Z_c$ is described within the hybrid nanoliquid film which separated total flow region in two zones. In one side of this curve, heat is transferred from the cylindrical surface to the hybrid nanoliquid film and in the other side, opposite scenario is observed.

Recent data show that assembly of repetitive-sequence, single-stranded DNA molecules (ssDNA) and carbon nanotubes (CNTs) depend on the specific sequence repeat. Therefore, it is of practical interest to assess various methods for generating single-stranded DNA molecules that contain repetitive sequences. Existing automated synthesis procedures for generating long (> 100 nt) ssDNA molecules generate ssDNA products of variable purity and yield. An alternative to automated synthesis is the polymerase chain reaction (PCR), which provides a powerful tool for the amplification of minute amounts of specific DNA sequences. Here we show that a modified asymmetric PCR method allows synthesis of long ssDNAs comprised of tandem repeats of the repetitive vertebrate telomeric sequence (TTAGGG)_n, and is also applicable to arbitrary (repetitive or nonrepetitive) DNA. Long, repetitive deoxynucleotides produced by automated synthesis are surprisingly heterogeneous with respect to both length and sequence. Benefits of the method described here are that long, repetitive ssDNA sequences are generated with high sequence fidelity and yield.

One of the important phenomena influencing the resistivity behavior of nanotubes based on the change of their radius is a physical effect called “pinch effect”. In this paper, according to the experimental results, the electrical resistivity behavior of carbon nanotubes is modeled as a function of the radius in the radius range of 3–10nm. The pinch effect is not observed for weak current, but if the radius of carbon nanotube is very small, this effect will be considerable and affects carbon nanotube resistivity. The deviations observed in $\rho$–$R$ (resistivity as a function of nanotube radius) diagrams for individual carbon nanotube are justified with different parameters such as pinch effect phenomenon. The results show an acceptable theoretical model for the behavior of electrical resistivity relative to radius reduction. The theory diagram of the electrical resistivity behavior of carbon nanotubes in terms of radius reduction is predicted in very small radii. These results are consistent with the experimental results. It is consistent and generalizable.

Carbon nanotubes (CNTs) can be fluidized in the form of fluidlike agglomerates made of many three-dimensional sub-agglomerates, having a multi-stage agglomerate (MSA) structure and containing large amounts of twisting CNTs of micrometer magnitude.

Poly(ortho-anisidine) (POA)/single-walled carbon nanotubes (SWCNTs) composite films have been prepared by means of oxidative potentiostatic electropolymerization of the monomer (ortho-anisidine) in the presence of purified SWCNTs. The magnetic properties of the obtained films have been investigated by electron spin resonance (ESR) (ν ≅ 9.4 GHz; temperature range 10–300 K) and compared with those of pure POA films in the same oxidation state. The similarity of the ESR signals and the dependence on temperature of the ESR line features suggest a polaron origin of the paramagnetic states. A strong increase of the ESR integral intensity has been detected for composite samples kept for 72 h in hydrogen atmosphere at room temperature. Under the same conditions, a less pronounced increase in the intensity has been detected in the case of pure polymer films. The kinetics of the hydrogen adsorption–desorption processes in the nanocomposite samples has been investigated and interpreted in the frame of an H-physisorption mechanism. The comparison between the H-induced effects in POA and nanocomposite POA/SWCNTs films has been carried out taking into account the structure of the samples and the presence of defects.

In this study, we demonstrated a novel method to grow carbon nanotubes (CNTs) by chloride-mediated chemical vapor deposition with hydride vapor-phase nucleated catalyst (HVPN). In the HVPN method, FeCl₂ as a catalyst precursor was produced by an in situ chemical reaction between Fe powder and HCl gas. After the synthesis of FeCl₂, CNTs were grown by supplying acetylene. We studied growth conditions for the catalyst formation process in HVPN method. High-quality CNT forests were grown by optimizing the FeCl₂ synthesis conditions. This study has established the HVPN method as a novel, highly controllable way to grow CNT forests.