Difference between revisions of "Passivation layer mineral"

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(initial page content moved out unchanged from Binary diamondoid compound)
 
(note on nickle and added link to wanted page Surface passivation)
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* Sn tin - SnO2 - wikipedia: [http://en.wikipedia.org/wiki/Tin_dioxide tim dioxide] - '''[http://en.wikipedia.org/wiki/Cassiterite cassiterite]'''
 
* Sn tin - SnO2 - wikipedia: [http://en.wikipedia.org/wiki/Tin_dioxide tim dioxide] - '''[http://en.wikipedia.org/wiki/Cassiterite cassiterite]'''
 
* Cu copper - wikipedia: [http://en.wikipedia.org/wiki/Patina patina] ...
 
* Cu copper - wikipedia: [http://en.wikipedia.org/wiki/Patina patina] ...
* Ni nickel - wikipedia: [http://en.wikipedia.org/wiki/Nickel(II)_fluoride nickel fluoride] - [http://en.wikipedia.org/wiki/Nickel_oxide nickel oxides] - '''[http://en.wikipedia.org/wiki/Bunsenite busenite]'''
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* Ni nickel - wikipedia: [http://en.wikipedia.org/wiki/Nickel(II)_fluoride nickel fluoride] - [http://en.wikipedia.org/wiki/Nickel_oxide nickel oxides] - '''[http://en.wikipedia.org/wiki/Bunsenite busenite]''' Nickel minerals can cause allergies through prolonged skin contact.
 
* Cr chromium ...
 
* Cr chromium ...
 
* V vanadium, Nb niobium ...
 
* V vanadium, Nb niobium ...
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* PbS Galena [https://en.wikipedia.org/wiki/Galena] Mohs 2.5-3 (soft)
 
* PbS Galena [https://en.wikipedia.org/wiki/Galena] Mohs 2.5-3 (soft)
  
=== Passivation of passivation layer minerals ===
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== Passivation of passivation layer minerals ==
  
 
Here an interesting problem occurs.
 
Here an interesting problem occurs.
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Specifically it is often a good idea to cover the whole surface with lone pairs of electrons. But further oxidation of an already oxidized material will probably not work or be rather unstable ['''to investigate for every specific situation'''].
 
Specifically it is often a good idea to cover the whole surface with lone pairs of electrons. But further oxidation of an already oxidized material will probably not work or be rather unstable ['''to investigate for every specific situation'''].
 
What should be doable almost always is hydrogen passivation. (Such passivation may cause higher friction due to high lateral spacing between the small hydrogen atoms sitting atop larger atoms and the low lateral stiffness of the single bonded hydrogen atoms)
 
What should be doable almost always is hydrogen passivation. (Such passivation may cause higher friction due to high lateral spacing between the small hydrogen atoms sitting atop larger atoms and the low lateral stiffness of the single bonded hydrogen atoms)
It may be necessary to find a special solution for each indivitual material - nitrogen phosphorus and sulfur may often be useful for plugging surfaces closed.
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It may be necessary to find a special solution for each indivitual material - nitrogen phosphorus and sulfur may often be useful for plugging surfaces closed. (See: [[Surface passivation]])

Revision as of 08:54, 4 December 2016

Passivation layer minerals of today's industrial metals

We do have daily skin contact with these minerals without even realizing it.
Often these minerals are naturally present as ores from which the metals are extracted.

wikipedia: passivation in general


  • PbS Galena [2] Mohs 2.5-3 (soft)

Passivation of passivation layer minerals

Here an interesting problem occurs. To prevent two atomically precisely flat blocks from fusing seamlessly together on contact their surfaces must look differently than their insides. Specifically it is often a good idea to cover the whole surface with lone pairs of electrons. But further oxidation of an already oxidized material will probably not work or be rather unstable [to investigate for every specific situation]. What should be doable almost always is hydrogen passivation. (Such passivation may cause higher friction due to high lateral spacing between the small hydrogen atoms sitting atop larger atoms and the low lateral stiffness of the single bonded hydrogen atoms) It may be necessary to find a special solution for each indivitual material - nitrogen phosphorus and sulfur may often be useful for plugging surfaces closed. (See: Surface passivation)