902 resultados para zinc metalloprotease


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Zinc is produced from ores by two general methods, distillation and electrolysis. The general principles involved in the electrolytic zinc process of today were known as far back as 1880. Difficulties encountered in purifying the solution for electrolysis and lack of suitable mechanical apparatus were the main reasons that such a long time elapsed before the process was used to produce zinc in commercial quantities.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this research was to investigate the possibilities of roasting and leaching a bulk copper-zinc sulfide concentrate, and the subsequent separation of the metals from the leach solution by electro­lytic deposition.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

It has been proven by research and years of experience, that before electrolytic zinc is possible, the electrolyte, as zinc sulfate solution must be prepared as pure as is economical. In other words, the ideal electrolyte must only be a solution of one metal - zinc. Every other metal and carbon must be excluded if good recovery and a firm deposit is to be obtained.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Reclaimed metals, or secondary metals, are becoming of great im­portance in the metal industries of the world. Secondary metals are an important factor in production. The increase in the secondary production of copper is due to many factors. One of these may be its permenance, that is, the metal does not corrode very readily. Another reason for increase in production is the high price paid for it.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The lead storage battery as it is used today is made up of the pasted type plates of lead dioxide, the anode, and sponge lead, the cathode, and wooden or hard rubber separators, which serve to insulate these from one another. In manufacturing these, it is desirable to keep them free from impurities.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The use of zinc as a structural metal has been militated against by two of its properties, namely, its low tensile strength and its susceptibility to grain growth. The importance of these factors can be appreciated when it is realized that the tensile strength of coarsely crystalline cast zinc is 4,000 pounds per square inch, while finely crystalline cast zinc has a tensile strength of 12,000 pounds per square inch.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The purpose of this research was to continue the work of Thomas Parker, who worked on the recovery of copper and zinc from brass during the school year l934 - 1935. Since there is such a wide variety of brasses made with usually a third alloying constituent, remelt­ed scrap is suitable only for castings of wide tolerance in specifications.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This investigation, carried on in the metallur­gical laboratories at the Montana School of Mines, was undertaken with the desire to work out a rapid method for the estimation, or the determination, of the amount of lead in zinc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The reclamation of metals from scrap is becoming increasingly important in the metallurgical industry. Copper, because it does not corrode readily and is electronegative to most common metals, is peculiarly adapted to reclamation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In metallurgical practice today some of the relatively rare metal Indium is recovered as a by-product from the ores of other metals. Indium is a soft, silvery—white metal belonging to the third group of the periodic classification. It is situated just above tin in the electrochemical series.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The ore under investigation in this thesis is a copper-zinc ore which came from the state of New Mexico. The exact location is unobtainable. The purpose of the investigation was to determine the most effective means of concentration of the valuable min­erals present in the ore.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Several methods have been investigated, with some success, for treating scrap brass to recover copper and zinc, either as pure metals or as salts of the metals. One of the more promising of these methods is electrolysis in sulfate solution for the recovery of pure copper and zinc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The measurement of current efficiency by hydrogen evolution is based on the assumption that the portion of the current which deposits no zinc will release hydrogen. This assumption is correct for solutions containing no impurities electropositive to zinc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Magnesium is one of the most active elements and forms oxides, nitrides, and carbides, but not hydrides. Due to its activity, low melting point, low strength when unalloyed, and the difficulty with which it is worked, magnesium has not been and is not at present well developed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Very little work has been done towards the recovery of zinc from mine water because the zinc content of the water is generally low. As different from copper, which can very easily be replaced by iron in any of its solutions, zinc is very high up in the electro-chemical series and so the few metals above zinc, most of which are rare and hence expensive, cannot be used to replace zinc from its solution.