Post-transition metal packing structure. Tin forms Zintl phases such as NaSn, BaSn, KSn and CaSn. It has good corrosion resistance in air on account of forming a thin protective oxide layer. Pure tin has no structural uses. It is used in lead-free solders, and as a hardening agent in alloys of other metals, such as copper, lead, titanium and zinc. Lead is a soft metal (MH 1.5, but hardens close to melting) which, in many cases, is unable to support its own weight. It has a close-packed structure (BCN 12) but an abnormally large inter-atomic distance that has been attributed to partial
C-element particular, the so-called Maevsky's implementation is a non-distributive circuit loosely based on. Non-distributivity is introduced sometimes to increase concurrency. The 3NAND gate in this circuit can be replaced by two 2NAND gates. The C-element using only two-input gates has been proposed by Tsirlin and then synthesized by Starodoubtsev et al. using Taxogram language. This circuit coincides with that attributed (without reference) to Bartky and can operate without the input latch. Yet another version of the C-element built on two RS latches has been synthesized by Murphy using Petrify tool. However, this circuit includes inverter connected to one if the inputs.