Search results
Results From The WOW.Com Content Network
Amitraz (development code BTS27419) is a non-systemic acaricide and insecticide [1] and has also been described as a scabicide. It was first synthesized by the Boots Co. in England in 1969. [2] Amitraz has been found to have an insect repellent effect, works as an insecticide and also as a pesticide synergist. [3]
The empty set is the set containing no elements. In mathematics, the empty set or void set is the unique set having no elements; its size or cardinality (count of elements in a set) is zero. [1] Some axiomatic set theories ensure that the empty set exists by including an axiom of empty set, while in other theories, its existence can be deduced.
In axiomatic set theory, the axiom of empty set, [1][2] also called the axiom of null set[3] and the axiom of existence, [4][5] is a statement that asserts the existence of a set with no elements. [3] It is an axiom of Kripke–Platek set theory and the variant of general set theory that Burgess (2005) calls "ST," and a demonstrable truth in ...
Formamide is an amide derived from formic acid. It is a colorless liquid which is miscible with water and has an ammonia -like odor. It is chemical feedstock for the manufacture of sulfa drugs and other pharmaceuticals, herbicides and pesticides, and in the manufacture of hydrocyanic acid. It has been used as a softener for paper and fiber.
3,4- Di methoxy phenethylamine (DMPEA) is a chemical compound of the phenethylamine class. It is an analogue of the major human neurotransmitter dopamine where the 3- and 4-position hydroxy groups have been replaced with methoxy groups. It is also closely related to mescaline which is 3,4,5-trimethoxyphenethylamine.
Partial orders. A reflexive, weak, [1] or non-strict partial order, [2] commonly referred to simply as a partial order, is a homogeneous relation ≤ on a set that is reflexive, antisymmetric, and transitive. That is, for all it must satisfy: Reflexivity: , i.e. every element is related to itself.
In set theory in mathematics and formal logic, two sets are said to be disjoint sets if they have no element in common. Equivalently, two disjoint sets are sets whose intersection is the empty set. [1] For example, {1, 2, 3} and {4, 5, 6} are disjoint sets, while {1, 2, 3} and {3, 4, 5} are not disjoint. A collection of two or more sets is ...
A family of sets is said to be union-closed if the union of any two sets from the family belongs to the family. The conjecture states: For every finite union-closed family of sets, other than the family containing only the empty set, there exists an element that belongs to at least half of the sets in the family.