The article by Silvia Merler is well-written and most importantly contains a number of neat graphics.
I think it is important to put the points raised into the wider economic context:
1. Making the access to the Western financial markets more difficult is just one outcome of the sanctions. It's effects, much discussed here, a far broader and cut deeper, especially together with the Russian 'counter'-sanctions.
2. As already mentioned before there are excellent reasons why Russian companies have foremost tapped into the European financial markets and not the Chinese one. The latter has been somewhat of a stop-gap, as it seems from the numbers. Shifting comes at a considerable price.
P.S: A good update about the currency reserves:
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