Chemistry

The vector stencils library "Periodic table of chemical elements" contains 119 icon symbols of chemical elements for drawing Mendeleev's periodic table, chemical diagrams, infographics and illustrations.
"A chemical element is a pure chemical substance consisting of a single type of atom distinguished by its atomic number, which is the number of protons in its atomic nucleus. Elements are divided into metals, metalloids, and non-metals. Familiar examples of elements are carbon, nitrogen, oxygen (non-metals), silicon, arsenic (metalloids), aluminium, iron, copper, gold, mercury, and lead (metals).
The lightest chemical elements, including hydrogen, helium and smaller amounts of lithium, beryllium and boron, are thought to have been produced by various cosmic processes during the Big Bang and cosmic-ray spallation. Production of heavier elements, from carbon to the very heaviest elements, proceeded by stellar nucleosynthesis, and these were made available for later solar system and planetary formation by planetary nebulae and supernovae, which blast these elements into space. The high abundance of oxygen, silicon, and iron on Earth reflects their common production in such stars. While most elements are generally stable, a small amount of natural transformation of one element to another also occurs in the decay of radioactive elements as well as other natural nuclear processes." [Chemical element. Wikipedia]
The chemical symbols example "Design elements - Periodic table of chemical elements" was created using the ConceptDraw PRO software extended with the Chemistry solution from the Science and Education area of ConceptDraw Solution Park.

The vector stencils library "UML package diagrams" contains 21 symbols for the ConceptDraw PRO diagramming and vector drawing software.
"A package diagram in the Unified Modeling Language depicts the dependencies between the packages that make up a model. ...
Elements.
(1) Package: It is a general purpose mechanism for organizing model elements & diagrams into groups. It provides an encapsulated namespace within which all the names must be unique. It is used to group semantically related elements. It is a namespace as well as an element that can be contained in other package's namespaces.
(2) Class: It is a representation of objects, that reflects their structure and behavior within the system. It is a template from which actually running instances are created. Classes usually describe logical structure of system.
(3) Interface: It is a specification of behavior. Implementing classes of an interface class are required to support the behavior.
(4) Object: It is an instance of class. It is often used in analysis to represent numerous artifacts and items that exist.
(5) Table: It is a stereotyped class." [Package diagram. Wikipedia]
The example "Design elements - UML package diagrams" is included in the Rapid UML solution from the Software Development area of ConceptDraw Solution Park.