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The paper presents the combination concept of a deep cryogenic treatment (DCT) with a nitriding process of 42CrMo4 steel. The DCT process at −180 °C was carried out immediately after the steel quenching, before subsequent tempering and nitriding. As a reference mode, an involving conventional heat treatment process as hardening, tempering and nitriding was carried out. A multi-stage gas nitriding process at 520 °C/32 h was used.

Two major species were identified in Fe-treated montmorillonite: monomeric or dimeric hydroxoaqua cations ${\rm{Fe}}({\rm{OH}})_x^{(3 - x) + }$ Fe(OH)x(3−x)+ (form I), and polymeric structures with edge-shared Fe(O,OH)6(form II). These species have different electron spectra (absorption maximum is 29,600 cm−1in form I, and 26,000 and 28,000 cm−1in form II), chemical and thermal stability, and electrochemical behavior. Form I behaves as a partly exchangeable cation in interaction with Cu2+from Cu-trien solution and Ni2+from Ni-EDTA, that can be used for selective quantitative analysis. On heating above the dehydration temperature (∼100–150°C) montmorillonite with Fe3+in form I is converted to a mica-like structure and Fe3+ions are fixed more strongly in the montmorillonite structure. Form II behaves similarly to hydrous ferric oxides, but its thermal crystallization to hematite is postponed to ∼500–600°C. The Fe3+cations in the interlayer space are much less thermally stable than Al pillars in pillared interlayered clays (PILCs). Form I is more active in oxidative dehydrogenation of propane, while form II is the active species in sorption of As and the non-specific combustion of propane. To produce only form II by the treatment of montmorillonite with Fe3+, its load must be kept below ∼20 wt.%; otherwise the usual hydrous ferric oxides are formed.

Laboratory powder X-ray microdiffraction with a focusing monocapillary and linear multichannel detector was applied to phase identification in fragments of painting layers of art works, canvas and wall paintings, and polychromes on wood. This method is useful in materials research of painting layers with complex stratigraphy, and it is indispensable in distinguishing inorganic pigments of different natural provenance and revealing degradation products. The advantage of X-ray microdiffraction is its nondestructive nature and no need of sample pretreatment. Samples after microdiffraction can hence be used for other analyses or archived. Another advantage is the possibility to work with samples smaller than 1 mm, which is particularly important in the analysis of artworks where the sample amount or size is a serious limit of using the laboratory techniques of materials research. The X-ray equipment used is more economical and more easily accessible than other microdiffraction techniques and is, hence, suitable for routine analytical work.

Square-wave voltammetry of solid naphthoquinone, anthraquinone, and flavone dyes, carmine, cochineal red, indigo, and Prussian blue, was compared to microanalysis (sample consumption <1 mg) of traditional painting pigments and dyes without their preliminary dissolution. Electrochemical analysis was also performed after the samples' hydrolysis simultaneously with thin-layer chromatography. Anthraquinone-based pigments and Prussian blue are reversibly reduced, cochineal red and lac dyes are irreversibly reduced, flavones are mostly reversibly oxidized, dragon's blood is irreversibly oxidized and reduced, and indigo yields both reversible oxidation and reduction. The potential window of these reactions is about 1.4 V wide. This variability permits identification of the kind of pigment or dye, and directly distinguishes, for example, alizarin and purpurin; luteolin and quercetin; or indigo and Prussian blue.Square-wave voltammetry of solid naphthoquinone, anthraquinone, and flavone dyes, carmine, cochineal red, indigo, and Prussian blue, was compared to microanalysis (sample consumption <1 mg) of traditional painting pigments and dyes without their preliminary dissolution. Electrochemical analysis was also performed after the samples' hydrolysis simultaneously with thin-layer chromatography. Anthraquinone-based pigments and Prussian blue are reversibly reduced, cochineal red and lac dyes are irreversibly reduced, flavones are mostly reversibly oxidized, dragon's blood is irreversibly oxidized and reduced, and indigo yields both reversible oxidation and reduction. The potential window of these reactions is about 1.4 V wide. This variability permits identification of the kind of pigment or dye, and directly distinguishes, for example, alizarin and purpurin; luteolin and quercetin; or indigo and Prussian blue.

Reduction of processing time is the goal of every business. In some cases, speeding up manufacturing processes is impossible or takes place at the expense of quality. The purpose of soft annealing is to obtain globular carbides in the microstructure. However, it is one of the most time-consuming heat treatment operations. Even its optimised versions require several hours of time. "Accelerated Carbide Spheroidisation and Refinement" (ASR) is an alternative process which can be performed using induction heating or thermomechanical treatment. It only takes several minutes to complete and has a beneficial effect on resultant mechanical properties. In this experiment, the impact of various microstructures in 54SiCr6 spring steel on hardening behaviour was explored. For this purpose, specimens with two different microstructures containing spheroidised carbides were produced by ASR accelerated annealing and by conventional soft annealing. Another initial microstructure, with lamellar pearlite, was obtained by hot rolling. It was found to have a certain effect as well. Quenched and tempered microstructures were observed using electron microscopy (SEM). Their mechanical properties were measured. The effects of various initial microstructures on resultant mechanical properties after cryogenic treatment were studied as well.

Single crystals of the title compound are obtained from an aqueous solutions of Cu(OAc)2(60 °C, 30 h) and the crystal structure is determined by single crystal XRD.