Boris Derjaguin
Encyclopedia
Professor Boris Vladimirovich Derjaguin (or Deryagin) (August 9, 1902, Moscow
– May 16, 1994) was one of the renowned Soviet
/Russia
n chemist
s of the twentieth century. As a member of the Russian Academy of Sciences
he laid the foundation of the modern science
of colloid
s and surface
s. An epoch in the development of the physical chemistry of colloids and surfaces is associated with his name.
Derjaguin became famous in scientific circles for his work on the stability of colloids and thin films of liquids which is now known as the DLVO theory, after the initials of its authors: Derjaguin, Landau, Verwey, and Overbeek. It is universally included in text books on colloid chemistry and is still widely applied in modern studies of interparticle forces in colloids. In particular, the Derjaguin approximation is widely used in order to approximate the interaction between curved surfaces from a knowledge of the interaction for planar ones.
Derjaguin was also briefly (and embarrassingly) involved in polywater
research during the 1960s and early 1970s. This field claimed that if water
was heated then cooled in quartz
capillaries, it took on astonishing new properties. Eventually, the scientists who were involved in polywater admitted it did not exist, claiming they were misled by poorly designed experiments.
He is also known for having hotly rejected some of the then-new ideas of adhesion as presented by the Western bloc in the 1970s. His model came to be known as the DMT (after Derjaguin, Muller and Toporov) model, while the model presented by Western bloc scientists came to be known as the JKR (after Johnson, Kendall and Roberts) model for adhesive elastic contact
. This rejection proved to be instrumental in the development of the Tabor and later Maugis parameters that quantify which contact model (of the JKR and DMT models) represent adhesive contact better for specific materials.
Moscow
Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...
– May 16, 1994) was one of the renowned Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
/Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
n chemist
Chemist
A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...
s of the twentieth century. As a member of the Russian Academy of Sciences
Russian Academy of Sciences
The Russian Academy of Sciences consists of the national academy of Russia and a network of scientific research institutes from across the Russian Federation as well as auxiliary scientific and social units like libraries, publishers and hospitals....
he laid the foundation of the modern science
Science
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...
of colloid
Colloid
A colloid is a substance microscopically dispersed evenly throughout another substance.A colloidal system consists of two separate phases: a dispersed phase and a continuous phase . A colloidal system may be solid, liquid, or gaseous.Many familiar substances are colloids, as shown in the chart below...
s and surface
Surface
In mathematics, specifically in topology, a surface is a two-dimensional topological manifold. The most familiar examples are those that arise as the boundaries of solid objects in ordinary three-dimensional Euclidean space R3 — for example, the surface of a ball...
s. An epoch in the development of the physical chemistry of colloids and surfaces is associated with his name.
Derjaguin became famous in scientific circles for his work on the stability of colloids and thin films of liquids which is now known as the DLVO theory, after the initials of its authors: Derjaguin, Landau, Verwey, and Overbeek. It is universally included in text books on colloid chemistry and is still widely applied in modern studies of interparticle forces in colloids. In particular, the Derjaguin approximation is widely used in order to approximate the interaction between curved surfaces from a knowledge of the interaction for planar ones.
Derjaguin was also briefly (and embarrassingly) involved in polywater
Polywater
Polywater was a hypothetical polymerized form of water that was the subject of much scientific controversy during the late 1960s. By 1969 the popular press had taken notice, and by 1970 doubts about its authenticity were being circulated. By 1973 it was found to be illusory...
research during the 1960s and early 1970s. This field claimed that if water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
was heated then cooled in quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
capillaries, it took on astonishing new properties. Eventually, the scientists who were involved in polywater admitted it did not exist, claiming they were misled by poorly designed experiments.
He is also known for having hotly rejected some of the then-new ideas of adhesion as presented by the Western bloc in the 1970s. His model came to be known as the DMT (after Derjaguin, Muller and Toporov) model, while the model presented by Western bloc scientists came to be known as the JKR (after Johnson, Kendall and Roberts) model for adhesive elastic contact
Contact mechanics
Contact mechanics is the study of the deformation of solids that touch each other at one or more points. The physical and mathematical formulation of the subject is built upon the mechanics of materials and continuum mechanics and focuses on computations involving elastic, viscoelastic, and plastic...
. This rejection proved to be instrumental in the development of the Tabor and later Maugis parameters that quantify which contact model (of the JKR and DMT models) represent adhesive contact better for specific materials.
See also
- Water memoryWater memoryWater memory is the claimed ability of water to retain a "memory" of substances previously dissolved in it to arbitrary dilution. No scientific evidence supports this claim. Shaking the water at each stage of a serial dilution is claimed to be necessary for an effect to occur...
- Pathological sciencePathological sciencePathological science is the process in science in which "people are tricked into false results ... by subjective effects, wishful thinking or threshold interactions". The term was first used by Irving Langmuir, Nobel Prize-winning chemist, during a 1953 colloquium at the Knolls Research Laboratory...