Libro de las categorías de las naciones

Of all the different areas in computational chemistry, density functional theory (DFT) enjoys the most rapid development. Even at the level of the local density approximation (LDA), which is computationally less demanding, DFT can usually provide better answers than Hartree-Fock formalism for large systems such as clusters and solids. For atoms and molecules, the results from DFT often rival those obtained by ab initio quantum chemistry, partly because larger basis sets can be used. Such encouraging results have in turn stimulated workers to further investigate the formal theory as well as...

Galaxies have a history. This has become clear from recent sky surveys which have shown that distant galaxies, formed early in the life of the Universe, differ from the nearby ones. New observational windows at ultraviolet, infrared and millimetric wavelengths (provided by ROSAT, IRAM, IUE, IRAS, ISO) have revealed that galaxies contain a wealth of components: very hot gas, atomic hydrogen, molecules, dust, dark matter ... A significant advance is expected due to new instruments (VLT, FIRST, XMM) which will allow one to explore the most distant Universe. Three Euroconferences have been...

Eighty-eight lavishly illustrated pages of stepby-step coloured drawings and photographs teaches you how to grow orchids confidently, successfully and professionally. Written for the amateur and the professional without access to sophisticated laboratory equipment and chemicals, this contains all you need to know to become an expert.

Química: origen y fronteras aborda cuestiones fundamentales de esta ciencia bajo las preguntas ¿qué somos?, ¿de dónde venimos?, ¿dónde estamos?, ¿para dónde vamos? Los autores desglosan temas y conceptos básicos de la química, y recorren aspectos de su evolución desde los primeros desarrollos experimentales hasta los avances recientes en el control de reacciones químicas y en la robótica molecular. Se trata de una introducción poco convencional a la química, puesto que propende por un acercamiento reflexivo a esta ciencia, sus preguntas y sus potenciales investigativos, y lo...