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This research investigates the effects of pack cementation parameters on the thermodynamics, growth kinetics, and microstructure of the simple and silicon‐modified aluminide coatings on the IN718 superalloy. The growth kinetic modelling of the aluminide coating, activated by NH4Cl, is established as h=174252.02T12WAl12WNH4Cl12t12exp-8306.5T ${h={{174252.02}\over{{T}^{{{1}\over{2}}}}}{W}_{Al}^{{{1}\over{2}}}{W}_{NH4Cl}^{{{1}\over{2}}}{t}^{{{1}\over{2}}}exp\left({{-8306.5}\over{T}}\right)}$. further optimizing the kinetics modelling that includes both CaCl2 activator or the mixture of CaCl2 and NH4Cl. The results showed that NH4Cl as an activator generated a higher equilibrium partial pressure of halides, which enhanced the deposition efficiency of active Al atoms and facilitated the significant precipitation of Cr‐rich carbides. Additionally, part of the CaCl2 substitute NH4Cl could maintain a high coating growth rate and reduce the hazards. Adding Si element preferentially combines with Cr formed the Cr9.1Si0.9 phase along grain boundaries, which blocked the inner‐diffusion channels of Al atoms and reduced the thickness of the silicon‐modified aluminide coating compared to simple aluminide coating. These researches revealed the relationship among the thermodynamics, growth kinetics, and microstructure of simple and silicon‐modified aluminide coatings. The thickness and microstructure of coatings can be effectively regulated by adjusting the powder composition, content, and process parameters to achieve precise control. [ABSTRACT FROM AUTHOR]

Copper/graphite/Ti 2 SnC composites were prepared using spark plasma sintering with copper-coated graphite powder, Ti 2 SnC powder, and copper powder as raw materials. The effect of sintering temperatures (800, 850, 900, and 950 °C) on the microstructure, relative density, hardness, resistivity, and tribological properties of the composites was studied in this paper. The results show that Cu and Ti 2 SnC demonstrate obvious inter-diffusion during sintering and become stronger with an increase in the sintering temperature, and the phase change process of the Cu matrix was in the order: Cu → Cu 5.6 Sn → Cu 41 Sn 11 → Cu 3 Sn. The relative density, hardness, friction coefficient, and the wear rate of the composites were the best when the sintering temperature was 900 °C, and their values were 97.21%, 67.68 HSD, 0.25, and 3.72 × 10−6 mm3/(N·m), respectively, whereas the resistivity of the composites was the best when the sintering temperature was 950 °C, and it was 6.116 × 10−7 Ω m. • Copper/Graphite/Ti 2 SnC composites were prepared by spark plasma sintering. • The composites samples were sintered at different temperatures (800, 850, 900, 950 °C). • The tribological properties, hardness, and resistivity of the composites samples were investigated. • The composites samples were analyzed by XRD, SEM, and EDS. [ABSTRACT FROM AUTHOR]

A new mercapto-terminated binuclear Cu(II) complex, [Cu 2 Cl 2 (mtboc) 2 (C 12 H 8 N 2 ) 2 ] [mtboc =2-(methylthio)benzo[ d ]oxazole-5-carboxylic acid] (Cu2), was synthesized and characterized by single-crystal X-ray diffraction studies. The Cu2 complex was then immobilized on the surface of Au electrodes through S Au bonds to form a self-assembled monolayer. The electrochemical properties of the as-prepared Cu2- modified Au electrode (Au/Cu2) were investigated using cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry (DPV). Moreover, as a biomimetic sensor for the determination of dopamine (DA) and uric acid (UA), the Au/Cu2 electrode exhibited excellent electrocatalytic activity for the oxidation of DA with a faster electron-transfer rate (6.61 s −1 ). The DPV technique was used for the trace determination of DA. The dependence of current vs. concentration was linear from 0.2 to 30 μM with a regression coefficient of 0.9975, and the detection limit of DA was ∼ 0.08 μM. Furthermore, the modified electrode clearly separated the DA signal from the interference effect of UA, thus realizing the simultaneous detection of DA and UA. Finally, the method was applied to the selective and precise analysis of DA in commercial injection and urine samples. [ABSTRACT FROM AUTHOR]

Glaucoma is the main cause of irreversible visual loss worldwide, and comprises a group of progressive, age-related, and chronic optic neuropathies. Prostaglandin analogs are considered a first-line treatment in the management of glaucoma and have the best efficacy in reducing intraocular pressure. When comparing these therapeutic agents between them, long-term therapy with 0.03% bimatoprost is the most effective followed by treatment with 0.005% latanoprost and 0.004% travoprost. The prevalence of adverse events is lower for latanoprost than for other prostaglandin analogs. However, some patients do not respond to the treatment with prostaglandin analogs (non-responders). Intraocular pressure-lowering efficacy differs significantly between individuals partly owing to genetic factors. Rs1045642 in ABCB1 , rs4241366 in SLCO2A1 , rs9503012 in GMDS , rs10306114 in PTGS1 , rs11568658 in MRP4 , rs10786455 and rs6686438 in PTGFR were reported to be positive with the response to prostaglandin analogs in patients with glaucoma. A negative association was found between single nucleotide polymorphisms of PTGFR (rs11578155 and rs6672484) and the response to prostaglandin analogs in patients with glaucoma. The current review is an analysis of the information relevant to prostaglandin analog treatments based on previous literatures. It describes in detail the clinical pharmacology and pharmacogenetics of drugs belonging to this therapeutical class to provide a sound pharmacological basis for their proper use in ophthalmological clinical practice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhou, Zhan and Wei.)