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Magnesium silicate hydrate (M-S-H) was prepared via one-pot hydrothermal synthesis and electrophoretically deposited (EPD) onto stainless steel substrate (Type 304), varying different process parameters. The optimal conditions for the EPD process were found to be as follows. A stable suspension of material was achieved using isopropanol containing 1% water as dispersing medium and Mg-nitrate as charging additive. The best coating was obtained after three successively repeated EPD processes at a voltage of 30 V, accompanied by drying at room temperature between each EPD cycle. The coating showed a thickness of 31 µm and very smooth surface. After calcination at 900 °C coating retains its adherence to the substrate but undergoes a structural transformation from poorly crystallized M-S-H to well-crystallized clinoenstatite phase which is known for its biocompatibility. As a result, it densifies and shrinks giving grainy and slightly rough surface. Structural properties and parameters of the magnesium silicate hydrate (M-S-H) and clinoenstatite were acquired by XRD technique, while morphology was examined by the analysis of SEM micrographs. This study demonstrates that: i) M-S-H can be synthesized through simple hydrothermal route starting from simple, low-cost precursors, ii) EPD process is an effective technique for deposition of M-S-H materials onto stainless steel and iii) inosilicate mineral (clinoenstatite) can be successfully obtained from M-S-H by calcination at 900 °C. HIGHLIGHTS Magnesium silicate hydrate (M-S-H) was prepared via a one-pot hydrothermal synthesis. The optimal conditions for the electrolytic deposition process were determined. Kinetics of the process were investigated using the Hamaker`s equation. Clinoenstatite can be successfully obtained from M-S-H by calcination.

In this review article, we summarize the current knowledge about the applicability of advanced oxidation processes (AOPs) such as UV/H2O2, Fenton and photo-Fenton for removal of textile dyes from wastewater and the effect of operational parameters (initial dye concentration, initial H2O2 concentration, initial Fe2+ concentration and initial pH) on these processes. Numerous studies have reported the use of AOPs for degradation of textile dyes, and the results show that they are very effective. By comparing the results of the previous studies, it seems that the photo- Fenton process is more efficient than the Fenton and UV/H2O2 process.

Preparation, characterization and application of materials modified with TiO2 nanoparticle have been reviewed. Chitosan, bacterial biomass and dendrimers were the starting material for modification. Sorbents characterization was performed by scanning electron microscopy (SEM). In order to investigate the sorption capabilities of sorbents, we used them for removal of heavy metal ions from aqueous solution. The effect of contact time on heavy metal ions sorption and maximum sorption capacities of biosorbents are shown. As a very important parameter of the sorption process, the effect of initial pH values on heavy metal removal was examined. This paper indicates that sorption using the material modified with TiO2 is becoming a promising alternative to conventional adsorbents in removing heavy metal ions.

Our studies concern the effects of different parameters on dyeing process of knitting materials with reactive vinyl sulphonic dyes. Based on the corresponding parameters correlations, an estimation of ultrasound application validity in dyeing processes of cotton - type textile substrates has been established. Desired color hue may be attained with application of ultrasound reducing dye concentration or shortening dyeing time for 20 min with reduction of salt concentration even to 20 g/dm3.

The present paper describes the assessment of colour parameters of industrial paints for horizontal signalization (designed as POM S1 and POM S2 / ZEB 1 and ZEB 2) of white colour hue, coming from two different producers ("Pomoravlje" and "Zorka") with reference to an independent sample (IND 0) and some physical properties of each sample. Colorimetric characterization of samples was performed using a reflectance spectrophotometer "Update Colour Eye 3000". Standard and modified test methods (ASTM) were performed to establish physical properties of the paints. The industrial paints show better values for the investigated parameters and properties and satisfy standards prescribed by law. POM S2 sample with dry film thickness, similar to the same of other samples, provides the best physical features maximizing quality and minimizing protection cost.

Scanning electronic microscope JSM-5300 (JEOL, Japan) has been used to investigate the structure of the PES fibers upper layers. Preparation of samples was performed by placing them on an aluminium support, with a glue or double-sided adhesive tape. The tool for spreading the conductive layer on the sample's surface, used in this work, was JFC-1100E ION SPUTTER (JEOL Co., Japan). Potential difference of electron acceleration was 30 kV, and multiplication of the samples was 3500 times. ORWO NP 20 DIN films were used for taking the photos. The samples were dyed with C.I.D. Yellow 23, in concentration of l%, at pH = 4.5, with the following acids added: acetic formic and oxalic. The results show absence of any internal damage in fiber structure. On the surface however, groups of particles have been observed varying in shape, magnitude and spacing density. Organic (acetic, formic and oxalic) acids used in the experiments caused differences in upper layers structures of dyed PES fibers. This is the main reason to induce differences in color (DE), chromaticity (DH) and lightness (DL), among the samples (with the all acids included) and a standard (addition of acetic acid only).

Due to the fact that oxidation-reduction potential and rH2 value of every water are its crucial features, numerous efforts have been made to use electrochemical means for water preparation. In this paper, we report the results of electrochemical influence research of magnesium-aluminium silicate catalyst, in the form of ceramics made of kaolinite and bentonite clays, on the rH2, pH and EOR changes of the waters of particular characteristics in the wanted direction. Particularly, the possibility of changing "active water" characteristics was investigated. The composite made with micro alloyed aluminium exhibits a very negative stationary potential and its interaction with water results in water reduction. Addition of some active components to the mixture of kaolin and bentonite can provide clay mixtures, which after sintering at high temperatures produce very porous ceramics with microcrystalline and amorphous regions of stoichiometric and nonstoichiometric new oxides and some metallized surface (in our case-mainly with magnesium surplus). Nonstoichiometric oxide mixtures and metallized amorphous ceramics regions show high electrochemical and chemical activities in contact with water. This leads to redox potential changes and appearance of Mg2+ ions in the magnesium aluminium silicate-water system.

In this paper, the steel active-passive anticorrosive protection was done. Steel plates samples with dimensions 40 ?100 ?2 millimeters were used. Samples surfaces preparation was done by degreasing, then by sandblasting by pneumatic pistol. The metallising by molten metal was done by hand pistol which worked with metal vein "Protector" (? 3,18 millimeters) of electrochemical active anode material on the basis of microalloyed aluminum. The mentioned application was done twice and obtained layer thickness was 150-200 micrometers. After this operation, organic coating "Vinilpom", the product of Coatings Industry "Pomoravlje", was applied. Coating quality was followed by measuring of coating thickness, of dried film hardness, level of connecting with a base and of gloss. Whole composition steel - "Protector", organic coating electrochemical study was done by measuring of galvanic team electrochemical potential change in 20% NaCl solution, during the time.