Soldering each type of solder and alloy has different melting temperatures. The term "silver solder" denotes the type of solder that is used. Some soft solders are "silver-bearing" alloys used to solder silver-plated items. Lead-based solders should not be used on precious metals because the lead dissolves the metal and disfigures it. The distinction between soldering and brazing is based on the melting temperature of the filler alloy. A temperature of 450 °C is usually used as a practical demarcation between soldering and brazing. Soft soldering can be done with a heated iron whereas the other methods typically require a higher
C-rich stability element and U-rich compared to the predominantly C-rich human element. Despite this shift the murine alpha globin mRNA is still as stable due to a complementary change in the specificity of the poly(C)-binding protein. C-rich stability element The C-rich stability element is a short part of a gene sequence important for the proper synthesis of globin and several other human proteins. Differences in the stabilities of individual mRNAs can dramatically affect the overall level of expression for genes. Eukaryotic mRNAs can have half-lives that vary from as short as several minutes to as long as several days. In differentiating human erythroid