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 utilitarianism morally. Others distinguish between 'strong' and 'weak' versions of negative utilitarianism, where strong versions are "only" concerned with reducing negative well-being, and weak versions say that "both" positive and negative well-being matter but that negative well-being matters more. Other versions of negative utilitarianism differ in how much weight they give to negative well-being ('disutility') compared to positive well-being (positive utility), as well as the different conceptions of what well-being (utility) is. For example, negative preference utilitarianism says that the well-being in an outcome depends on frustrated preferences. Negative hedonistic utilitarianism thinks of well-being in terms of pleasant and unpleasant experiences.