Year: 2022

PERIODIC TABLE. A thoughtful summary of the understanding of the evolution of the elements of the Periodic Table, except for the conclusions. https://lnkd.in/gx-8DrP View in LinkedIn

“THE CNO CYCLE refers to the Carbon-Nitrogen-Oxygen cycle, a process of stellar nucleosynthesis in which stars on the Main Sequence fuse hydrogen into helium via a six-stage sequence of reactions.” C12 —> N13 —> C13 —> N14 —> O15 —> N15 —> C12. “Thus, the carbon-12 nucleus used in the initial reaction is regenerated in the final one and hence acts as a catalyst for the whole cycle. Stars of lower mass convert hydrogen to helium via an alternative process known as the ‘proton-proton chain’.“ https://lnkd.in/gfyaz5f View in LinkedIn

CHEMICAL EVOLUTION OF GALAXIES. “Galactic chemical evolution (GCE), in particular, has provided stringent constraints on stellar yields. Different elements are produced from stars on different timescales. Therefore, elemental and isotopic abundance ratios evolve as a function of time in a galaxy.” https://lnkd.in/gg9biYa View in LinkedIn

THE PERIODIC TABLE of the elements showing stellar origin of each element, such as the Big Bang, Supernovae, Large Stars, Small, Stars and Cosmic Rays. A brilliant and very original compilation. https://lnkd.in/gYqQejP View in LinkedIn

ARTIFICIAL SYNTHESIS. “Rutherford was the first to transform one element into another: nitrogen plus helium —> oxygen and hydrogen. Since then, a number of artificial elements have been generated.” https://physics.info/nucleosynthesis/ View in LinkedIn

DUAL USE TECHNOLOGY. “The first experimental evidence that elements (really nuclei) can change from one type to another occurred some half-century ago during the basic research that led ultimately to the development of the atomic bomb.” https://lnkd.in/eGDp3CB View in LinkedIn

STAR CHEMISTRY. “Advances in experimental techniques that measure nuclear reactions that occur in stars are opening new opportunities for understanding the stellar and chemical evolution of our Universe.” https://lnkd.in/e3QFknM View in LinkedIn

SO ENDS this contemplation of the origin of the elements. Is it just the way that the human mind works that makes a seemingly chaotic universe appear orderly, when we can arrange the elements in an exquisitely logical and orderly sequence called the Periodic Table, or is there a genuine order to that swirling universe? Or that we can take a burning dying star and infer such linear equations of elemental synthesis from a planetary body in collapse? An important but hard to answer question. View in LinkedIn

AUTODESTRUCTIVE DEFENSE. "Many organisms, including humans, develop autoimmune disorders, which effectively defend against enemies but compromise fitness by attacking healthy tissue." https://lnkd.in/e5R5vQe View in LinkedIn

SEVERE ALLERGY. “As a consequence, some individuals in a population might be vulnerable to anaphylactic shock, in which comparatively harmless allergens provoke potentially fatal systemic immune reactions.” https://lnkd.in/g3Bfjaa View in LinkedIn