National Physical Laboratory of India is realized by using an absolute radiometer. For practical work, a group of tungsten incandescent lamps are used. The level of uncertainty is ± 1.3 × 10. Experimental work has been initiated to realize mole, the SI unit for amount of substance The NPL does not maintain standards of measurements for ionizing radiations. This is the responsibility of the Homi Bhabha Atomic Research Centre, Mumbai. The standards maintained at NPL are periodically compared with standards maintained at other National Metrological Institutes in the world as well as the BIPM in Paris. This exercise ensures that Indian national standards are equivalent
The Net (substance) The Net (substance) The Net, in alchemy, is an alloy of copper and iron, whose crystal structure induces a network pattern on its surface. It was described in the 17th century by Sir Isaac Newton. Newton produced the substance by following what he regarded as a recipe, encoded in classical mythology, for part of the process of achieving the philosopher's stone. The relevant myth involved the god Vulcan finding his wife Venus (alchemical symbol for copper) in bed with the god Mars (alchemical symbol for iron) Newton's interpretation rested on typical alchemical associations, construing Vulcan as a stand-in for fire,