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WOS: 000446711300053, The corrosion resistances of three different thermochemical coatings (grown using titanizing, boriding, and borotitanizing treatments) applied to STKM-13A steel surfaces were investigated. The coatings were characterized using optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffractometry, 2D profilometry, and microhardness experiments. The corrosion tests were conducted using both electrochemical and static immersion methods, in 3.5 pct NaCl and 40 pct HF acid solutions, respectively. The corrosion resistance of STKM-13A steel was enhanced after the coating process. The specimens were exposed to more corrosion in the HF solution than in the NaCl solution. The best corrosion resistance was obtained in the borotitanized and borided specimens immersed in the NaCl and HF solutions, respectively. The borided STKM-13A steel sample showed even less cumulative weight loss than Inconel 625 in the static immersion HF acid solution test. This suggests potential use of the borided STKM-13A steel in the uranium production units of nuclear power plants as an alternative to more costly alternatives such as Monel, Inconel, and Hastelloy. (C) The Minerals, Metals & Materials Society and ASM International 2018

Laboratory experiments were used to examine the influence of cellulose and straw on denitrification and N immobilization in a sandy loam soil. The soil was mixed with 300 μg nitrate-N/g and incubated in a special vessel under conditions that changed from aerobic to anaerobic or in the permanent absence of O2. Gases (O2, CO2, N2, N2O, NO and CH4) were analysed by gas chromatography at regular intervals and the soil was examined for nitrate, nitrite, ammonium and cellulose. Compared with controls, the application of straw and cellulose (0.5% and 1.0%, respectively) enhanced nitrate immobilization and decreased denitrification, under both anaerobic and originally aerobic (PO2 = 20 vol%) conditions. However, a comparison of results from the aerobic and the anaerobic incubations shows that an increase in denitrification and N immobilization was apparent at an original O2 concentration of 20 vol%. N2 was the major product of denitrification in all experiments. Free methane was apparent as soon as nitrate was respired. The stimulating effect of O2 on total denitrification in the presence of relatively high amounts of easily decomposable cellulose is ascribed to a higher turnover and an intensified mineralization rate (CO2 production), which increased the total demand for electron acceptors.