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This theoretical study examines the effects of thermal radiation, viscous dissipation, and a magnetic field effect on a nanofluid that contains carbon nanotubes in blood and moves over a two-way expanding surface. We consider both the stretching and contracting directions when examining the bidirectional nature of the expanding surface. We define the problem’s governing equations, which include energy and momentum, and transform them into a set of ordinary differential equations using suitable similarity transformations. We semi-numerically solve the resulting equations using HAM methods and the BVPh. 2.0 program. We also discuss the consequences of heat radiation and viscosity dissipation in the nanofluid. The Rosseland approximation models the effect of thermal radiation, while the incorporation of fluid’s internal friction represents viscous dissipation. This research aims to investigate the combined effects of various parameters, such as thermal radiation, Eckert number, nanoparticle volume fraction, couple stress parameter, power law index, magnetic field, and Prandtl number, on the heat, flow, and transfer properties of single-walled carbon nanotube (SWCNT), multi-walled carbon nanotube (MWCNT), and blood-based nanofluids. A fascinating field of study, this study will reveal useful details about the possible uses of carbon nanotube blood-based nanofluids across bidirectional expanding surfaces in drug delivery systems, heat transfer processes, and biomedical engineering. Blood-based nanofluids can benefit from the inclusion of carbon nanotubes to improve fluid behavior and thermal conductivity, which is crucial for a number of industrial and medicinal applications.

In this paper, the nanocrystalling composite Mg-Ni-TiO₂-CNTs was made by mechanical ball milling under hydrogen pressure of 5.0×10^-5Pa, The hydrogen storage properties and operation temperatures were investigated. It was found that the composite can absorb 7.5wt.% hydrogen in 60s under 5.0×10^-5Pa hydrogen pressure and desorb 6.5wt% hydrogen in 600s at 260°C under 5.0×10^-5Pa hydrogen pressure. The composite has very high absorption, hydrogen capacity and remarkable kinetic properties in hydriding /dehydeiding process. TiO₂, Ni and CNTs were used as additive to improve the hydrogen storage performance. They can be utilized as an effective catalyst to improve hydriding/dehydriding performance of hydrogen storage material and lead to pronounced enhancement on the hydrogen storage property of Mg. The results showed that the composite has potential application in the future.

Here we used the iron oxide nanoparticles derived from ferritin as catalyst for the synthesis of carbon nanotubes (CNTs) by the chemical vapor deposition (CVD) of coal gas. It has been found that the structure and morphology of CNTs can be tailored, to some degree, by varying the experimental conditions such as catalyst loading and process parameters. In addition to straight CNTs, some Y-branched CNTs were also obtained, which might be due to the sulfur species in the coal gas.

Multi-walled carbon nanotubes (CNTs) were grown via pyrolytic chemical vapor deposition technique and explored for their infrared sensing behavior. CNT synthesis was carried out over cobalt zinc ferrite $({\mathrm{\text{Co}}}_{0.5}{\mathrm{\text{Zn}}}_{0.5}{\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_4)$ catalyst nanoparticles under different gas flow conditions to control outside diameter of the nanotubes. It was found that a progressive decrease in the carbon precursor gas (acetylene in this case) from 5:1 to 9:1 (v/v) causes reduction of average CNT diameter from 85 nm to 635 nm. Growth conditions involving higher temperatures yield nanotubes/nanofibers with outer diameter of $>$500 nm, presumably due to surface aggregation of nanoparticles or increased flux of carbonaceous species at the catalyst surface or both. Current–voltage characteristics of the nanotubes depending on the CNT diameter, revealed linear or nonlinear behavior. When incorporated as sensing layer, the sensitivity of $\sim$5.3 was noticed with response time of $\sim$4.1 s. It is believed that IR sensing characteristics of such CNT-based detectors can be further enhanced through post-synthesis purification and chemical functionalization treatments.

In this paper, we study the behavior of three-dimensional extremely-short optical pulses propagating in a system made of carbon nanotubes in the presence of an external magnetic field applied perpendicular both to the nanotube axis and to the direction of propagation of the pulse. The evolution of the electromagnetic field is classically derived on the basis of the Maxwell’s equations. The electronic system of carbon nanotubes is considered in the low-temperature approximation. Our analysis reveals the novel and unique ability of controlling the shape of propagating short optical pulses by tuning the intensity of the applied magnetic field. This effect paves the way for the possible development of innovative applications in optoelectronics.

The Fe–Ni–P matrix composites reinforced with carbon nanotubes (CNTs) were prepared by means of liquid phase sintering at 950${}^{\circ }$C. The effects of the mass fraction of CNTs on the microstructures and properties of the composites were investigated. It is noteworthy that the structures of CNTs were hardly damaged during the sintering process via evaluation of microstructures on as-sintered composites. The strength and ductility increased gradually with the increase of CNT content while the saturation magnetization decreased gradually. The sample containing 1 wt.% CNTs showed a good combination of a compression ratio of 60% and a compressive strength of approximately 3800 MPa, which indicated its potential application in modern power generation systems.