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Cluster-like network structures of single-walled carbon nanotubes (SWNTs) were synthesized by chemical grafting poly 2-hydroxyethyl methacrylate (polyHEMA) to the sidewalls of SWNTs. Acid chloride-functionalized tubes were coupled with commercially available HEMA monomer, which was in turn polymerized using a radical initiator. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to identify the surface changes on the nanocomposites. Microscopic observations of the nanotube complexes by field emission scanning electron microscopy (FE-SEM) show that the tubes were dispersed and formed cluster-like network, branched structures with less bundling, thus, strongly suggesting a firm coating of the polymer on nanotube walls. The coating was further confirmed by transmission electron microscopy. The thermal properties of the nanotube complex as studied by thermal gravimetric analysis (TGA) revealed that coating enhanced stability of the complex, when compared to that of bulk polyHEMA and pristine SWNTs. The nanotube complexes showed excellent suspension stability when dispersed in organic solvent.

In this study, the effect of copper ion (Cu${}^{2+}$) was investigated on the film formation rate of Ti-based nanoceramic conversion layer on a ST12 type mild steel. At the first step, the film formation properties of the Ti conversion layer were characterized using DC polarization technique and FE-SEM micrographs. In the next step, concentration of Cu ion was optimized in the Ti solution bath, and finally, the rate of Ti ion (Ti${}^{4+}$) consumption in the conversion solution bath, with and without Cu ion, was detected by spectrophotometric technique using a dye-metal indicator. It was revealed that the addition of Cu ion to the Ti solution bath could increase the precipitation rate of Ti-based compounds on the mild steel substrate, leading to increment of film formation rate of the conversion layer.

Straw combines are intended to process the remaining harvested straw. When cut at high temperatures and in abrasive conditions, the cutting blade of straw combines undergoes substantial surface deterioration. This deterioration shortens the blade’s lifespan and increases the cutting cost of the machine. In recent decades, cryogenic treatments have played a significant role in enhancing material properties. In this paper, cryogenic treatment is utilized to boost the wear resistance of straw combine blades in the current investigation. The performance of cryogenic treatment was tested in the laboratory using the pin-on-disc wear tester with sample type, load, sliding velocity, and time serving as process factors and wear loss as the response parameter. The smoothness of the cryogenically-treated sample’s surface is certified through morphological examination. Specific wear rate and field emission scanning electron microscope (FE-SEM) indicated that cryogenic treatment enhances the grain structure and intermolecular interaction of the specimen, resulting in an increase in wear resistance. As opposed to the untreated specimen, the wear on the treated surface is uniform over the entire surface, as demonstrated by FE-SEM analysis. The grain structure and intermolecular bonding of the specimen were improved as a result of the cryogenic treatment. The cryogenic treatment increased the cost of the cutter bar and chopping cylinder blades by 9.38% and 13.61%, respectively, compared to untreated blades, but the increased cost was fully offset by the longer blade life.

This work estimates the optimum process parameters for the double-layer deposition of aluminum 6063 over EN8 medium carbon steel using friction surfacing. The control process parameters like axial force and feed rate of the consumable rod on two different deposition surface conditions, i.e. a good interface and a course interface during the process were investigated. The second layer deposition was performed over the roughness developed after the first layer deposition and contributed largely to the mechanical anchoring mechanism at the second coating interface. Assessment of the mechanical strength at the first coating interface (substrate/ coating 1) and second coating interface (coating 1/ coating 2) through bending and microhardness tests at both the interfaces was performed. The bending test results disclosed the existence of small delamination with no cracking at the second interface with a feed rate of 150mm/min at axial force of 5kN. An increase of 16.2% in the hardness value of consumable aluminum was seen at the first coating interface region. In contrast, the mean hardness at the second coating interface region was nearly the same as that of the consumable rod. Extensive studies of the surface coating and the microstructural features at both interfaces were performed through FESEM and EDAX analyses.

The scope of the present work is in enhancing the particle size, and dielectric properties of Mg-substituted Cobalt ferrites nanoparticles prepared by sol–gel auto combustion method. The different ratios of Mg-substituted Co Ferrites (Co${}_{1-x}$Mg_xFe₂O₄($x=0.00$, 0.05, 0.10, 0.15, 0.20 and 0.30)) are calcinated at 850${}^{\circ }$C. The synthesized nanoparticles were characterized by powder XRD, FTIR, FE-SEM, EDX techniques and dielectric behavior. The structural parameters were confirmed from powder XRD and the average particle size is obtained from 39 to 67 nm due to the substitution of Mg${}^{2+}$ which was calculated by Debye Scherrer’s formula. FE-SEM showed the surface morphology of the different ratio of the sample. The dielectric loss has measured the frequency range of 50Hz–5MHz. From electrical modulus, conductivity relaxation and thermal activation of charge carriers has been discussed.

In this study, zinc oxide was prepared by pulsed laser ablation method (PLAL), which is an easy-to-use and inexpensive physical method. The optical properties were studied using UV-Vis spectrometers, structure properties by (XRD) to calculate the crystalline size, and particle size determination by Field emission scanning electron microscopy (FE-SEM) and (EDS), transmission electron microscopy (TEM) assays and it was proved that they are within the ideal nanoscale for biological application. These ZnO NPs were employed on the inhibitory activity of different types of Gram-positive and Gram-negative bacteria, as well as on fungi, and it was noted their ability to penetrate the bacterial cell wall and inhibit its action.

To learn how the manner of preparation influences film development, this study examined film expansion under a variety of deposition settings. To learn about the membrane’s properties and to ascertain the optimal pretreatment conditions, which are represented by ambient temperature and pressure, Laser pressure of 2.5m bar, the laser energy density of 500mJ, distortion ratio ($x=0.5$) as a function of laser pulse count, all achieved with the double-frequency Nd: YAG laser operating in quality-factor mode at 1064nm. Mg_xZn${}_{1-x}$ films of thickness $10\pm 200$nm were deposited on glass substrates at pulse frequencies of (1–6)Hz and pulse durations of 10ns. The spectrum of rays. The X-rays demonstrated that the diffraction peaks’ findings show that the crystallinity of the films is highly dependent on the quantity of magnesium present in the layers. All the generated movies feature a polycrystalline hexagonal membrane structure, with the (101) plane being the main reflection. The average particle size was determined to be less than 50nm using FE-SEM measurements, and (RMS) of the surface roughness of the membranes Mg_xZn${}_{1-x}$ may be calculated using AFM analysis. The spectrum spans from (300)nm to (900) nm in wavelength. All films have a transmittance rate of more than 70% for the visible area of the spectrum$=$(400–800)nm, and in one model, it reaches greater than 95%. The energy gap (Eg) for these films is (2.68, 2.6, 2.4 and 2.32) electron volts, with a standard deviation of (100, 200, 300, and 400) shoot. In addition, the energy gap values drop as the laser pulse strength increases, and the range in which these values may be set is quite narrow (2.68–2.32).

This paper describes the synthesis of ZnO nanoparticles using air microplasma jets as the main reaction medium. Various techniques, including X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV—Vis spectroscopy, were employed to confirm the characterization of the artificially synthesized ZnO nanoparticles. The absence of additional peaks associated with secondary phases of ZnO, as revealed by the XRD analysis, indicates the exceptional purity of these nanoparticles. Through the use of SEM, we examined the surface morphology and observed a substantial rate of agglomeration. The energy band gaps of ZnO nanoparticles were determined to be 3.3 electron volts (eV). The cytotoxic effects of zinc oxide nanoparticles were assessed using the methyl thiazolyl tetrazolium (MTT) assay on breast cancer cells exposed to various doses of the nanoparticles. The Acridine-Orange/Ethidium-bromide (AO/EB) dual stain was employed to assess apoptotic cells. The data indicate that ZnO NPs can induce apoptosis, suggesting their potential as an anticancer treatment in breast cancer cell lines. The presented findings indicate that nanoscale zinc oxide particles (ZnO NPs) possess significant potential for future utilization in many biological applications. An example of such an application could be the prospective substitution for chemotherapy in the management of various forms of cancer diseases.

Nanocrystalline 3C-SiC is irradiated by neutron flux ($2\times 10^{13}$n/cm²s) up to 20h in the TRIGA Mark II type research reactor. At the first stage, silicon carbide nanoparticles were analyzed by scanning electron microscope (SEM) and transmission electron microscope (TEM) devices before and after neutron irradiation. Amorphous transformation and agglomeration effects on the permittivity of nanocrystalline silicon carbide (3C-SiC) were comparisons investigated before and after neutron irradiation. Dielectric spectroscopies of nanocrystalline 3C-SiC have been conducted at the frequency ranges of 0.1Hz–2.5MHz and temperature ranges of 100–400K. Real and imaginary parts of the permittivity of the nanomaterial were analyzed for comparison before and after neutron irradiation. Neutron irradiation increased dopant elements concentration in the nanocrystalline 3C-SiC particles, and that directly affects dielectric polarization and increased permittivity. All the mechanisms of the observed effects are given in the work.

This research set out to provide a faster, easier, and more efficient process for nanoparticle (NP) synthesis of aluminum oxide NPs preparation by microwave irradiation, using plant extracts separately and in the same way (tea, coffee, rosemary), which is an easy-to-use and inexpensive method. The structural properties were investigated by X-ray diffractometer analysis technique (XRD). The X-ray analysis shows the structure has a polycrystalline nature with a hexagonal phase. The optical properties were studied using ultraviolet visible (UV-Vis) spectrometer, where the energy gap was determined. The surface morphology properties of the prepared aluminum NPs were examined by atomic force microscope (AFM). The Fourier transform infrared (FTIR) spectroscopy verified the presence of Al-O, C–O, and C–H bonds, this study confirms the high reducing and capping capacity of aluminum NPs via biomolecules found in the plant extract. The inhibitory activity of these Al₂O₃-NPs was observed, along with their potential to enter the bacterial cell wall and hinder its activity.