ChemGlobe: Neptunium - http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/93.html
Electronic, thermal, and steric data along with an isotope table. |
ChemicalElements.com: Neptunium - http://www.chemicalelements.com/elements/np.html
Basic information, atomic structure, and isotopes table. |
Encyclopedia Britannica: Neptunium - http://www.britannica.com/EBchecked/topic/409383/neptunium
Overview, discovery, structure and properties. |
EnvironmentalChemistry.com: Neptunium - http://environmentalchemistry.com/yogi/periodic/Np.html
Atomic structure, chemical and physical properties, and table of nuclides. |
It's Elemental: Neptunium - http://education.jlab.org/itselemental/ele093.html
Basic physical and historical information. |
LANL: Neptunium - http://periodic.lanl.gov/elements/93.html
Basic information and history. |
Lenntech: Neptunium - http://www.lenntech.com/Periodic-chart-elements/Np-en.htm
Physical data, chemical properties, health and environmental effects. |
Visual Elements: Neptunium - http://www.chemsoc.org/viselements/pages/neptunium.html
General and physical information, source, and key isotopes. |
WebElements: Neptunium - http://www.webelements.com/webelements/elements/text/Np/key.html
Extensive information on history, uses, compounds, and properties. |
Wikipedia: Neptunium - http://en.wikipedia.org/wiki/Neptunium
Notable characteristics, history, occurrence, isotopes, and weapons applications. |