Jacob N. Israelachvili “[Water], It’s so small and simple and common, and yet it’s very complicated.” - Jacob Israelachvili, 2006
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rofessor Israelachvili’s work has focused on understanding the intermolecular and surface forces
and interactions of physical and chemical systems that determine the structure and properties (both static and dynamic) of complex fluid and soft matter systems, i.e., colloids, interfacial phenomena and separations systems in general, and in particular, polymers, selfassembling systems, biomolecules, membranes, in both aqueous electrolyte and nonaqueous liquids. His work has led to new fundamental insights as well as practical advances in technological/industrial areas of engineering and bioengineering such as personal care products (e.g., cosmetics, detergents), paints and coatings, adhesives and lubricants, pharmaceuticals, food emulsions, green processing, composites, solvents, oil and perfume extractions, absorptive materials, etc. His work as also contributed to the understanding and creation of new materials with large length scales from the super-macro (crustal plates and earthquakes) to the sub-nano regime (atomic lattice commensurability effects on adhesion and friction), and time scales, for example, clarifying continuous transitions between solids and liquids. In particular, his recent research into dynamic (non-equilibrium, transient, hysteretic, rate-, time- and history-dependent interactions and phenomena) have opened the way for studying non-equilibrium phenomena that are central to many technological, such as, ‘directed-assembly’ versus ‘self-assembly’, processes and, of course,
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biological systems and mechanisms. Within this broad area, Professor Israelachvili’s research contributions have had a profound effect on our understanding of the basic underlying molecular forces that control the physics of an enormous class of colloidbased and biological materials. His contributions to the scientific underpinnings of understanding adhesion and bioadhesion phenomena have been enormous. He truly stands out as a modern day giant of the field. In 1971, Israelachvili and Adams published a landmark paper describing the design of an apparatus in which two solid surfaces could be brought in a controlled way to within a few angstroms of one another in order to measure precise force vs distance relationships between the surfaces in vapor or liquid. There are several features of this invention that persist in their power and novelty 40 years later. This surface forces apparatus (SFA) is the only method that can make accurate force-surface separation measurements between two macroscopic surfaces (on which controlled surface chemistries can be constructed), in contrast to atomic force microscopy which uses small, generally uncharacterized, probes. The SFA is also the only method that can directly measure absolute distances (surface separations) directly since the contact position, contact area and surface profiles (e.g., deformed shapes) can be unambiguously and accurately determined. There are major classes of problems in intersurface, colloidal,