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With the appropriate choice of the imaginary current densities, the fields inside the surface or outside the surface can be deduced from the imaginary currents. [4] In a radiation problem with given current density sources, electric current density J 1 {\displaystyle J_{1}} and magnetic current density M 1 {\displaystyle M_{1}} , the tangential ...
Iridium is a chemical element; it has symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group , it is considered the second-densest naturally occurring metal (after osmium ) with a density of 22.56 g/cm 3 (0.815 lb/cu in) as defined by experimental X-ray crystallography .
Thus element 164 with 7d 10 9s 0 is noted by Fricke et al. to be analogous to palladium with 4d 10 5s 0, and they consider elements 157–172 to have chemical analogies to groups 3–18 (though they are ambivalent on whether elements 165 and 166 are more like group 1 and 2 elements or more like group 11 and 12 elements, respectively). Thus ...
Deuterated molecules, which contain at least one deuterium (2 H) atom, have slightly different masses and are listed in a separate table. The total number of unique species, including distinct ionization states, is indicated in each section header. Most of the molecules detected so far are organic.
Visualization of a celestial sphere. In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth.All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, which may be centered on Earth or the observer.
Even so, as physicists started to synthesize elements that are not found in nature, they found the stability decreased as the nuclei became heavier. [17] Thus, they speculated that the periodic table might come to an end. The discoverers of plutonium (element 94) considered naming it "ultimium", thinking it was the last. [18]
Einsteinium is the element with the highest atomic number which has been observed in macroscopic quantities in its pure form as einsteinium-253. [4] Like all synthetic transuranium elements, isotopes of einsteinium are very radioactive and are considered highly dangerous to health on ingestion. [5]
The above argument shows explicitly why the surface terms can cancel, but lacks generality. Alternatively, one can treat the case of lossless surrounding media with radiation boundary conditions imposed via the limiting absorption principle (LAP): Taking the limit as the losses (the imaginary part of ε) go to zero. For any nonzero loss, the ...