Influence of pH Galvanic Baths on the Nickel Deposits

The influence of pH on cathodic and anodic current efficiency, surface quality and morphology of nickel deposit in the electrolyte solutions of the Watts bath type was investigated. Cathodic current efficiency of nickel deposit is maximum for electrolytic bath whose pH value is about 4 and decreases for an electrolytic bath with a higher pH. The deposited thickness is a significant parameter because the thickness determining may establish if the deposition corresponds to the destination application deposition or not; and the measurements were made by non-destructive physical methods. The properties of nickel deposits, brightness and hardness are influenced by the pH of the bath electrolyte. The surface morphology of nickel deposit was analyzed by scanning electronic microscopy (SEM). The results showed that the structure of nickel deposits is influenced by pH of the bath. The pH increasing causes structural changes on the deposits in fine to coarse, while the electrodeposited nickel at pH 6.21 has a compact morphology with many cracks

Studies About Electrochemical Plating with Zinc-Nickel Alloys

The electrochemical deposition of zinc and combinations with elements of the 8th group of the Periodic System (nickel, cobalt, iron) have good properties for anticorrosive protection, compare with pure zinc. For steel pieces, these films delay apparition and formation of white and red iron oxide. We used solutions with different concentrations of zinc chloride, nickel chloride and potassium chloride. For analyze the results we utilized the optic microscope and the X-ray diffraction

Influence of Technological Parameters on the Evolution of Nickel Films Deposited by Electrolysis

The influence of technological parameters on the structure of nickel layers electrodeposited on a copper substrate in a Watts bath has been studied. The complex influence of current densities, temperature and pH values on the formation of the deposition layers are compared. The surface morphology of the nickel films was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). X-ray diffraction (XRD) was used to investigate the crystallinity of the prepared samples. The increase in the current density leads to fine crystallized films, while layers obtained at even higher current density have dendritic structures. The temperature increasing results in a structure change from fine to coarse

CHEMICAL AND PHYSICAL CHARACTERIZATION OF COMMON BEAN (PHASEOLUS VULGARIS L.) LANDRACES BY NORTH – NORTH-WESTERN EXTREMITY OF ROMANIA

The aim of our study was to characterize beans (Phaseolus vulgaris L.), one of the most important legumes at the international level, by examining their physical and biochemical properties, to highlight the importance of preserving local bean varieties in Romania, beans which are kept in the collection of the Mihai Cristea Suceava Plant Genetic Resources Bank. Local cultures of Phaseolus vulgaris, have been best preserved, especially in the Maramureș area, followed by Suceava area. Based on all 28 samples from the common bean germplasm collection, the mean values for seed size characteristics were seed length (L) 14.64 ± 2.24 mm and seed width (W) 8.93 ± 1.51 mm. The average weight of the 1,000-seed characteristic was 521.34 g, with the minimum and maximum values ranging from 136.96 to 1,045 g for all 28 samples. The highest coefficient of variation was calculated for 1,000-seeds weight (39.9 %) and the lowest for L/W (13.2 %). The protein content determined for 16 samples from the common bean germplasm collection was 23.79 ± 2.49 g/ 100 g of dry matter. The amount of protein varies between 18.84 g/ 100 g of dry matter (sample F23) and 26.69 g/ 100 g of dry matter (sample F27). The free amino acid content varies between 0.56 g/100 of dry matter and 1.29 g/100 g of dry matter, and the boiling time between 35 and 80 minutes. Boiling time is dictated by the variety of beans, but a very interesting thing, observed from the analyses carried out, is that the boiling time varies inversely with the percentage of protein. So, in sample F27 we have a boiling time of 35 minutes and a protein content of 26.69 g/ 100 g of dry matter. The sample with the highest protein content has the lowest boiling time. At the same time, sample F19 has a boiling time of 80 minutes and a protein content of 19.44 g/ 100 g of dry matter