20 research outputs found
Study of the Kinetics of Cadmium Cementation in the Presence of a Flocculant
Восстановление ионов кадмия из водных растворов проводили порошком цинка,
крупностью от 63 до 200 мкм. В ряде опытов проверяли влияние на процесс цементации кадмия
катионоактивного флокулянта Besfloc K6645. Процесс проводили в области температур от 30
до 50 оС при непрерывном перемешивании со скоростью 200 об/мин верхнеприводной мешалкой.
Кинетические кривые построили с использованием кадмий-селективного
электрода. Показано,
что повышение температуры протекания реакции положительно влияет на цементацию. Введение
в электролит флокулянта в количестве 70 мг/л снижало степень цементации кадмия. Полученные
данные позволили рассчитать кажущиеся энергии активации, которые составили при проведении
процесса без добавки флокулянта ориентировочно 46, 33 и 11 кДж/моль на первом, втором
и третьем участках кинетических кривых, соответственно, при проведении восстановления без
добавки флокулянта и 117–130 и 82–85 кДж/моль в присутствии флокулянта Besfloc K6645. При
восстановлении кадмия в присутствии флокулянта кажущаяся энергия активации возрастала
более чем в два разаThe reduction of cadmium ions from aqueous solutions was carried out with zinc powder, particle size from 63 to 200 μm. In a number of experiments, the influence of the cationic flocculant Besfloc K6645 on the cadmium cementation process was tested. The process was carried out in the temperature range from 30 to 50 °C with continuous stirring at a speed of 200 rpm with an overhead stirrer. Kinetic curves were built using a cadmium selective electrode. It is shown that an increase in the reaction temperature has a positive effect on cementation. The introduction of a flocculant in the amount of 70 mg/l into the electrolyte reduced the degree of cadmium cementation. respectively, when carrying out the reduction without the addition of a flocculant, and 117–130 and 82–85 kJ/mol in the presence of the Besfloc K6645 flocculant. When cadmium was reduced in the presence of a flocculant, the apparent activation energy more than double
Additive chiral interaction on interfaces of "Heavy metal/Ferromagnet" structures for enhancement of the Dzyaloshinskii-Moriya interaction
Additive chiral interaction on interfaces of "Heavy metal/Ferromagnet" structures for enhancement of the Dzyaloshinskii-Moriya interaction
Magnetic and magnetoresistance properties of Co nanostrips self-organized on step-bunched surfaces
Magnetic and magnetoresistance properties of Co nanostrips self-organized on step-bunched surfaces
Combination of the Methods of symmetrical components and Double Entry to Increase the Reliability of Digital Differential Relay Protection
The method of symmetrical components is one of the main methods used to calculate asymmetric modes in electric power systems. To increase the reliability of digital differential relay protection in case of asymmetric faults, a combination of symmetric components and double entry methods is proposed. It is supposed to compile balance equations, to apply the theory of graphs and matrices, and the estimation of reliability indicators is carried out on the basis of the method of Markov chains. The obtained results allow to make a conclusion about the prospects of implementing a differential protection using the method of double entry and symmetrical components in the electrical networks