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 Post subject: Re: Нуждаюсь в совете
PostPosted: 27 May 2022 21:29 
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Molybdic, of course.
À propos,
Volodymyr wrote:
Nickel is very common in vacuum tubes.
- nickel is a part of invar, alloy which may be welded with glass. Connectors are made of that alloy.


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 27 May 2022 21:47 
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in high-power lamps, the anode is often made of nickel foil.


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 28 May 2022 11:11 
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The shiny coating on the glass is barium. The gas absorber located within the plate - an alloy of barium and aluminum, to which titanium or nickel powder is added.
It is impossible to make a getter from pure barium, it will be oxidized even during the assembly of the radio tube.

When heated, a reaction occurs BaAl4 + 4Ni = 4NiAl + Ba

Nickel (or titanium) binds aluminum into a weakly evaporates NiAl compound. This avoids the evaporation of aluminum and contamination of barium in the shiny coating.
Such contamination leads to a decrease in the sorption capacity and low mechanical strength of the shiny coating.

The plate for the getter is made of invar (Fe + 36% Ni) or frigidal (Fe + 33% Ni + 1% Cr) alloy.
These alloys have very low thermal conductivity. This allows you to protect the getter from premature evaporation, in the process of degassing the radio tube.


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 28 May 2022 17:06 
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hello! what do you think it is? unfortunately, I don't have a label photo.


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 28 May 2022 17:50 
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N-(tert-Butoxycarbonyl)-L-alanine?
CAS 15761-38-3


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 28 May 2022 18:36 
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thanks! maybe it is. I found isomers but they're a lot.


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 01 Jun 2022 09:42 
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hello. what interesting things i can make with toluene-3,4- dithiol in organic synthesis, complexes, etc.?


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 01 Jun 2022 10:19 
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vano34 wrote:
hello. what interesting things i can make with toluene-3,4- dithiol in organic synthesis, complexes, etc.?

This is an analytical reagent. For example, for tin and molybdenum.

Clark, R. E. D.; Neville, R. C. (1959). Toluene-3,4-dithiol and its derivatives as analytical reagents: A new approach to qualitative inorganic analysis. // Journal of Chemical Education, 36(8), 390–
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File comment: Clark, R. E. D.; Neville, R. C. (1959). Toluene-3,4-dithiol and its derivatives as analytical reagents: A new approach to qualitative inorganic analysis. // Journal of Chemical Education
ed036p390.pdf [4.08 MiB]
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Sn -
Марченко З. Фотометрическое определение элементов (1971) viewtopic.php?p=27452#p27452
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Mo -
Бусев А.И. - Аналитическая химия молибдена http://chemistry-chemists.com/book5/him ... ov/Mo.djvu
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 Post subject: Re: Нуждаюсь в совете
PostPosted: 01 Jun 2022 15:09 
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thanks! I just want a solid complex in the vial, can i make it easily what do you think?


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 01 Jun 2022 18:55 
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The complex with tin is insoluble in water. Dithiol is used as a solution in 2% sodium hydroxide. The solution is oxidized by air - prepare before synthesis.
(the quote from the book is in the post above).

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 Post subject: Re: Нуждаюсь в совете
PostPosted: 02 Jun 2022 16:42 
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Thank you so much!


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 09 Jun 2022 22:20 
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Hello! I want to make something interesting from these compounds, I don't want polymers. what can I make? I will get any idea.

4,4'-Dichlorobiphenyl
Diphenyl sulfone
4,4'-Dichlorodiphenyl sulfone
4,4′-(Propane-2,2-diyl)diphenol


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 12 Jun 2022 23:29 
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Добрый день! Есть ли у уважаемого сообщества литература или практический опыт по крашению тканей. Обратились тут ко мне волонтеры которые плетут сетки. На них надо много лоскутков тканей зеленого, коричневого и подобных цветов. Они сейчас пробуют разные натуральные штуки по типу луковой шелухи и результаты так себе. Можете что то посоветовать?


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 13 Jun 2022 12:44 
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viewtopic.php?p=187830#p187830

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 Post subject: Re: Нуждаюсь в совете
PostPosted: 14 Jun 2022 11:18 
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Спасибо! Попробую почитать


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 16 Jun 2022 17:57 
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hello, I want to try this organic reaction. I have perchloric acid, but as I know it's hard to make chromium 2+ salts, I don't have chromium metal to make divalent salt from its amalgam. is there another way which worth to try?


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 16 Jun 2022 18:50 
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Cr(III) or Cr(VI) + Zn + HCl (aq) => Cr(II) (blue)

Is it possible to use HClO4 (aq) instead of HCl (aq)? I don't know.

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 Post subject: Re: Нуждаюсь в совете
PostPosted: 16 Jun 2022 18:56 
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thank you! I've seen an atomic reduction reaction, but I thought it would not be very stable in solution. I will try to use zinc to see what comes out.


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 Post subject: Re: Нуждаюсь в совете
PostPosted: 16 Jun 2022 19:15 
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Cr(II) is easily oxidized by air. It gradually reacts with water.

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 Post subject: Re: Нуждаюсь в совете
PostPosted: 16 Jun 2022 22:08 
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thanks. yes, that's a problem.


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