Chemical ionization source, the reagent gas is present in large excess compared to the analyte. Electrons entering the source with energy around 200-500 eV will preferentially ionize the reagent gas. Then, the ion/molecule reactions produces more stable reagent ions and the resultant collisions with other reagent gas molecules will create an ionization plasma. Positive and negative ions of the analyte are formed by reactions with this plasma. The following reactions are possible with methane as the reagent gas. If ammonia is the reagent gas, For isobutane as the reagent gas, Self chemical ionization is possible if the reagent ion is an ionized
Negative and positive rights obligates others to act with respect to the right holder. In the framework of the Kantian categorical imperative, negative rights can be associated with perfect duties while positive rights can be connected to imperfect duties. Belief in a distinction between positive and negative rights is usually maintained, or emphasized, by libertarians, who believe that positive rights do not exist until they are created by contract. The United Nations Universal Declaration of Human Rights lists both positive and negative rights (but does not identify them as such). The constitutions of most liberal democracies guarantee negative rights, but not all include positive