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Magnesium alloys, because of their excellent strength-to-weight ratio, are increasingly used in many industries. When used in external elements, the key factor is to provide adequate anticorrosion protection. High-temperature, cured-powder coatings are widely used to protect most metals, but their use on magnesium alloys is difficult as a result of the instability of the magnesium substrate at elevated temperatures. Another problem is ensuring the proper adhesion of the organic coating to the magnesium substrate. This paper presents the procedure for the synthesis of a duplex coating on AZ91 magnesium alloy. The topcoat was a powder coating based on acrylic resin, the main ingredient of which was glycidyl methacrylate. Because of the presence of epoxy groups, the coating was cured using ultraviolet (UV) radiation (low-temperature technology). The conversion subcoating was produced by plasma electrolytic oxidation (PEO) in an alkaline silicate electrolyte. The synthesized coating system was tested, among others, for microscopic (SEM), adhesive (mesh of cuts), and anticorrosion (EIS). The duplex PEO/UV-curable powder coating showed very good adhesion to the metal and increased the anticorrosion properties of the magnesium substrate, compared to the powder coating produced directly on the magnesium alloy and on an alternative conversion coating (synthesized in the process of chemical zircon phosphating). [ABSTRACT FROM AUTHOR]

The role of the oxide layer in the corrosion of aluminium in hydrochloric, sulphuric(VI) and orthophosphoric acid is studied at pH 1. The oxide layer is stable in hydrochloric and sulphuric acids. The corrosion rate of aluminium in these solutions is 0.2 and 0.3 mm/year, respectively. The oxide layer is unstable in orthophosphoric acid and the corrosion rate is higher, 1.75 mm/year. The corrosion process is studied using scanning electron microscopy, immersion and electrochemical techniques. The mechanism of corrosion of aluminium in the orthophosphoric acid solution is proposed. It includes the adsorption of a reaction intermediate on the surface of the corroding metal and the formation of the oxide layer at anodic potentials with respect to the open‐circuit potential. It is also explained when the inductive loop appears on the electrochemical impedance spectra of aluminium corroding in orthophosphoric acid solution. The mechanism of aluminium corrosion in hydrochloric and sulphuric acid is more complex compared to orthophosphoric acid, and is not analysed in detail. [ABSTRACT FROM AUTHOR]

The objective of this work was to test vanadium isopolyoxoanions as potential corrosion inhibitors of the intermetallic phase Al 2 Cu in sulfuric acid solutions at pH = 1.3 and 2.5. The intermetallic was melted in an electric arc furnace. Its phase composition was confirmed using X-ray diffraction, light microscopy, and differential scanning calorimetry. Then Al 2 Cu corrosion kinetics was studied. Chemical composition of the solution after corrosion was determined using inductively coupled plasma-optical emission spectroscopy. The surface of corroded specimens was analyzed using scanning electron microscopy and X-ray photoelectron spectroscopy. Subsequent electrochemical studies involved determination of open-circuit potential, electrochemical impedance spectra, and polarization curves. It was found that the Al 2 Cu phase corrodes selectively and vanadium isopolyoxoanions increase this process both at pH = 1.3 and 2.5 with two exceptions. Corrosion inhibition was observed for 100 and 200 mM of Na 3 VO 4 at pH 1.3, with inhibition efficiency 78% and 62% respectively, due to precipitation of V 2 O 5 .

Introduction: Activity of factor VIII (FVIII) increased above 150% of reference range predisposes to venous thromboembolism (VTE). The aim of this study was to identify predictors of increased FVIII activity in patients following VTE., Materials and Methods: 241 (38% men) patients presented due to objectively documented VTE episode at least 3 months ago were included in this study. FVIII activity was measured using a clotting assay on the analyzer BCS XP., Results: Among 241 patients with VTE, activity of FVIII above 150% (FVIII ≥ 150%) was observed in 96 (40%). These patients were older (p = 0.035) and their concentrations of fibrinogen and C-reactive protein (CRP) were higher by 12% and 88% (p < 0.001), respectively, compared with other patients. There was a positive correlation between FVIII and fibrinogen (r = 0.34; p < 0.001), FVIII and CRP (r = 0.30; p < 0.001). Type of treatment, time from the VTE episode and type of VTE were not associated with FVIII. Twenty patients (8%) had activity of FVIII increased above 200% (FVIII > 200%) and this group was also older (p = 0.015), more patients in that group had obesity (p = 0.015), idiopathic VTE (p = 0.043), less of them had positive family history (p = 0.010) and they were characterized by fibrinogen and CRP increased by 28% (p < 0.001) and 102% (p = 0.004), respectively, compared with patients with FVIII between 150-200%. Independent predictors of FVIII ≥ 150% were: fibrinogen (p < 0.001), bilirubin (p = 0.002), hemoglobin (p = 0.016), glucose (p = 0.040), CRP (p = 0.023), total homocysteine (p = 0.032). Fibrinogen was the only independent predictor of FVIII > 200% (p = 0.016)., Conclusions: The activity of FVIII in patients after VTE episode is influenced by age, concentration of fibrinogen, bilirubin, hemoglobin, glucose, CRP and homocysteine. Our results suggest the role of environmental factors, mainly inflammatory response in maintaining elevated FVIII activity following VTE.

Adipose tissue is a dynamic endocrine organ that is essential to regulation of metabolism in humans. A new approach to mental disorders led to research on involvement of adipokines in the etiology of mental disorders and mood states and their impact on the health status of psychiatric patients, as well as the effects of treatment for mental health disorders on plasma levels of adipokines. There is evidence that disturbances in adipokine secretion are important in the pathogenesis, clinical presentation and outcome of mental disorders. Admittedly leptin and adiponectin are involved in pathophysiology of depression. A lot of disturbances in secretion and plasma levels of adipokines are observed in eating disorders with a significant impact on the symptoms and course of a disease. It is still a question whether observed dysregulation of adipokines secretion are primary or secondary. Moreover findings in this area are somewhat inconsistent, owing to differences in patient age, sex, socioeconomic status, smoking habits, level of physical activity, eating pathology, general health or medication. This was the rationale for our detailed investigation into the role of the endocrine functions of adipose tissue in mental disorders. It seems that we are continually at the beginning of understanding of the relation between adipose tissue and mental disorders.