Reactive plasma spraying (RPS) is a promising technology for the in situ formation of several ceramic coatings. The focus of this paper is to summarize the state of our current knowledge about the RPS process and using the nitriding of Al particles and the fabrication of aluminum nitride coatings, as a case study. The aspects and challenges in this process such as the influence of the plasma power, in-flight time, particle size, nitriding mechanism, splat morphology, in-flight particle diagnostics, N2 plasma gas, and the feeding rate on the RPS process are analyzed and discussed. 相似文献
The effects of the surface charge type and density C496, C492 and A130LMW polyacrylamides (PAMs) on the rheological behavior of real industrial papermaking suspensions were quantitatively related to the degree of flocculation for the same industrial papermaking suspensions. The floc sizes were larger but less dense when anionic PAM was used, and this due to the repulsive forces between the anionic PAM and colloidal particles, leading to the development of open structure flocs of less density. On the other hand, rheological measurements showed that the papermaking suspension is thixotropic with a measurable yield stress. The results showed that the magnitude of the critical stress, τc, complex viscosity, η*, elastic modulus, G′, and viscous modulus, G″, depend on the number of interactions between the PAM chains and particle surface and the strength of those interactions. Cationic PAM showed higher values of η*, G′, G″ and τc compared to anionic PAM. This behavior is in good agreement with Bingham yield stress, τB, adsorption and effective floc density results. Similar to oscillatory measurements, creep measurements also showed that the deformation was much lower for the cationic PAM based suspensions than for the anionic PAM based suspensions. Furthermore, the results revealed that increasing the cationic PAM surface charge decreases the floc size but increases the adsorption rate, elasticity and effective floc density proposing differences in the floc structures, which are not revealed clearly in the Bingham yield stress measurements. 相似文献
Protection of Metals and Physical Chemistry of Surfaces - AISI 316 L austenitic stainless steel is widely used in various sectors of the industry (chemical, petro-chemical industry, paper industry,... 相似文献
Journal of Applied Electrochemistry - Modern technologies continuously need special materials with specific properties to adopt the desired application. Recently, numerous researches have been... 相似文献
In this study, mercury iodide (HgI2) nanoparticles (NPs) were synthesized by pulsed laser ablation in ethanol at laser fluences of 22.9, 33.1, and 43.3 J/cm2. The effect of laser fluence on the structural and optical properties of HgI2 NPs was studied. X-ray diffraction findings reveal that all synthesized HgI2 samples were polycrystalline in nature with orthorhombic structure. Absorption peak was appeared at 474 nm and the optical energy gap of HgI2 NPs decreases from 2.13 to 2.05 eV as laser fluence increased from 22.9 to 43.3 J/cm2. Zeta potential (ZP) results confirm that the nanoparticles synthesized at 22.9 and 33.1 J/cm2 have high degree of stability. Fluorescence measurements show the presence of several emission bands. Raman spectra of HgI2 NPs show the presence of six vibration modes centered at 15, 29, 37, 44, 51, and 70 cm?1. Fourier transform infrared (FT-IR) results show the presence of two bonds, namely, C–O and Hg-I. Transmission Electron Microscope (TEM) results showed that the formation of spherical nanoparticles for sample prepared at 22.9 J/cm2, 25–75 nm in size. While the nanoparticles synthesized with 33.1 and 43.3 J/cm2 exhibit nanorods and nanotubes morphologies, respectively. The dark I–V characteristics of β-HgI2 NPs/Si heterojunction photodetectors show rectification properties and the junction quality depends on the laser fluence and the best junction characteristics was obtained for heterojunction prepared at 33.1 J/cm2. The white light photosensitivity of the HgI2/p-Si photodetectors was measured at reverse bias under different intensities. The maximum responsivity reached was 3.39A/W at 450 nm for photodetector prepared at 33.1 J/cm2.
A series of dihydropyrimidinone-based antimalarial compounds were designed and synthesised based on the previously identified amide-based quinoline hybrids which showed good resistance reversal ability against the resistant strain of Plasmodium falciparum. The aromatic ring on the dihydropyrimidinone of the original hits was exchanged for a methyl group to bring the molecular weights below 500 Da and also determine the effect of the aromatic ring count on the resistance reversal ability of the hybrids. Apart from the previously used amide bond, the hybrid linker was also extended to the triazole linker. Although the triazole linker is synthetically easier to access, the use of an amide linker seems to have an activity advantage. The synthesised compounds in addition to the previously identified hits were subjected to molecular docking particularly targeting the orthosteric site of Plasmodium falciparum glutathione reductase (PfGR) protein. The ligand with the best binding interaction was rationally optimised to increase its suitability as a competitive inhibitor against the cofactor of the PfGR. Two of the optimised ligands showed better binding affinities than the cofactor while one of the two ligands displayed hydrophobically packed correlated hydrogen-bond which is very important in maintaining the ligand stability within the protein. In silico ADME predictions of the synthesised compounds indicate that these compounds possess good pharmacokinetic properties. 相似文献