Levitating Droplet Clusters ISBN Print: 978-1-56700-532-5 ISBN Online: 978-1-56700-533-2 Alexander A. Fedorets (University of Tyumen, X-BIO Institute, 6 Volodarsky St, Tyumen, 625003, Russia) Leonid A. Dombrovsky (Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, Russia; University of Tyumen,… Read More
Our new article on the asymmetry of protein folding and unfolding, and how this asymmetry can be used to create new folding algorithms. The molecule usually unfolds 100 times faster than it folds (although the rate, depends on temperature). We… Read More
Ramachandran, R.; Nosonovsky, M. “Kirchhoff’s Analogy between the Kapitza Pendulum Stability and Buckling of a Wavy Beam under Tensile Loading.” Appl. Mech. 2023, 4, 248-253. https://doi.org/10.3390/applmech4010014 Our paper is about a non-trivial analogy between the stabilization of an inverted pendulum… Read More
Johansson gauge blocks (“Jo blocks”) are made of steel and used for precision length measurement. Their surface is very smooth, and two blocks can adhere to each other, however, the strong adhesion occurs only after the sliding (wringing). Various hypotheses… Read More
High-strength materials that are able to resist impact usually have high hardness and high elastic moduli, facilitating also high speeds of elastic waves (sound), so that resulting shock waves quickly dissipate impact energy. Based on theoretical considerations, there is a… Read More
The levitating microdroplet cluster is a new phenomenon, which was discovered for the first time in 2004 by Alexander Fedorets. The droplet cluster is typologically similar to self-assembled colloidal crystals, but it has some features absent from colloidal clystals. Thus,… Read More
There are many interesting and unusual effects related to the levitating droplet cluster. Most of these have been discovered very recently. Besides the regular (hexagonally arranged) cluster, there is a chain cluster including the branched cluster, small clusters, and the… Read More
Scaling in physical chemistry is a fascinating issue since it combines temporal, spatial, and temperature domains. For a random walk or Brownian motion (the Einstein-Smoluchowski diffusion), the distance is proportional to power 1/2 of the path, R ~ sqr(L). There… Read More
1) M Zhukov, MS Hasan, P Nesterov, M Sabbouh, O Burdulenko, E V. Skorb, and M Nosonovsky* 2022 “Topological Data Analysis of Nanoscale Roughness in Brass Samples” ACS Appl. Mater. Interfaces 2021, https://doi.org/10.1021/acsami.1c20694 Rough surfaces possess complex topographies, which cannot… Read More
The mathematical method of separation of motions represents the effect of fast high-frequency oscillations by an effective averaged force or potential. Ultrasound acoustic vibrations are an example of such rapid oscillations leading to cavitation in water due to the gas… Read More
Our research in Triboinformatics, both at UWM and at ITMO, has covered two main directions: 1. Using machine-learing methods to establish correlations between tribological properties (friction and wear) and composition of composite materials. * MS Hasan, A Kordijazi, PK Rohatgi,… Read More
Our new triboinformatics paper just got accepted: Md Syam Hasan and Michael Nosonovsky 2021 “Topological data analysis for friction modeling” Europhysics Letters, DOI: https://doi.org/10.1209/0295-5075/ac2655 Abstract – Dry sliding friction is a complex but ubiquitous phenomenon. Experimental studies of friction produce… Read More
Symmetry and orderliness of two-dimensional (2D) levitating microdroplet clusters are quantified with the Voronoi entropy (VE) and the continuous symmetry measure (CSM). The time evolution of both VE and CSM is investigated. To compare the correlation between the two measures… Read More
1. Why viruses prefer water environment? Maybe there are reasons, which can be explained by physics, not biology. How the information cycle is related to the life cycle through the Landauer principle, which connects physics and information? Bormashenko, E.; Fedorets,… Read More
Md Syam Hasan, K. Sobolev, and M. Nosonovsky. Evaporation of droplets capable of bearing viruses airborne and on hydrophobic surfaces, J. Appl. Phys. 129, 024703 (2021); https://doi.org/10.1063/5.0023501 See also LA Dombrovsky, AA Fedorets, VY Levashov, AP Kryukov, E Bormashenko, M… Read More
Our paper on the cover of the MDPI Applied Mechanics journal A. S. Blumenthal and M. Nosonovsky 2020. Friction and Dynamics of Verge and Foliot: How the Invention of the Pendulum Made Clocks Much More Accurate Appl. Mech. 2020, 1(2),… Read More
News about the study of the droplet cluster 1. The Ring Cluster is a new type of droplet clusters, and is reported in our new paper: A A Fedorets, D Shcherbakov, L A Dombrovsky, E Bormashenko, M Nosonovsky 2020 “Impact… Read More
The subjects of tribology, which is defined as the study of the interaction of solid surfaces in their relative motion, are friction, wear, lubrication, surface properties, and adhesion. Since the term tribology was introduced by Peter H. Jost in 1966,… Read More
Allometry is a type of scaling in biology, which explains how various parameters (such as the metabolism rate, speed, and even the lifespan of an animal) depend on the average body mass. Ergodicity is a concept in the theory of… Read More
Our paper about the invention of the pendulum clock mechanism: Blumenthal, A.S.; Nosonovsky, M. Friction and Dynamics of Verge and Foliot: How the Invention of the Pendulum Made Clocks Much More Accurate. Appl. Mech. 2020, 1, 111-122. https://doi.org/10.3390/applmech1020008 “The pendulum… Read More
Small droplet clusters have unusual symmetries absent from colloidal crystals and from large clusters. In our new paper, we discuss the hypothesis that the symmetries of small clusters may be related to an amazing mathematical object, the ADE-classification based on… Read More
Our new paper about clusters in physics, chemistry, and biology and their relation to networks. E Bormashenko, A. A. Fedorets, M. Frenkel, L. A. Dombrovsky and M. Nosonovsky. “Clustering and self-organization in small-scale natural and artificial systems”Phil. Trans. R. Soc…. Read More
We had a number of recent papers in collaboration with the department of Materials Science & Engineering (Prof. Pradeep Rohatgi’s group) on the development of new metallic materials (alloys and nano-composites) with corrosion-resistant and water-resistant properties. I think this shows… Read More
In addition to the hexagonally ordered clusters of levitating micro-droplets, a cluster with a chain structure can exist. The first systematic observation of this new phenomenon is reported in our paper: A. A. Fedorets et al. “Self-arranged levitating droplet clusters:… Read More
Our new paper: A. A. Fedorets, N. E. Aktaev, D. N. Gabyshev, E. Bormashenko, L. A. Dombrovsky, M. Nosonovsky “Oscillatory Motion of a Droplet Cluster” J. Phys. Chem. C 2019 The work was done mostly by young Russian colleagues, Drs…. Read More
Usually I write here about papers, of which I either an author or a co-author. This paper is mostly a contribution of a graduate student, Mehran Rahmani. He took my graduate course on Vibrations and decided to do a project… Read More
Together with our collaborators from Civil Engineering, we are designing new superhydrophobic concrete pavements and we want to ensure that the hydrophobicity (water repellency) does not mean that the pavement is slippery in terms of traction / friction. Pavements and… Read More
Our new paper “Ternary Logic of Motion to Resolve Kinematic Frictional Paradoxes” by Michael Nosonovsky and Alexander D. Breki is published in Entropy 2019, 21(6), 620; https://doi.org/10.3390/e21060620 Abstract Paradoxes of dry friction were discovered by Painlevé in 1895 and caused… Read More
A new paper by our international group: A. Fedorets, L. A. Dombrovsky, E. Bormashenko and M. Nosonovsky “On relative contribution of electrostatic and aerodynamic effects to dynamics of a levitating droplet cluster” Int. J. Heat Mass Transfer, 133 (2019) 712-717…. Read More
Our review paper about the Voronoi entropy. Bormashenko, E.; Frenkel, M.; Vilk, A.; Legchenkova, I.; Fedorets, A.A.; Aktaev, N.E.; Dombrovsky, L.A.; Nosonovsky, M. Characterization of Self-Assembled 2D Patterns with Voronoi Entropy. Entropy 2018, 20, 956. https://www.mdpi.com/1099-4300/20/12/956 The Voronoi entropy is… Read More
A. Breki and M. Nosonovsky “”Ultraslow frictional sliding and the stick-slip transition,” Appl. Phys Lett. 113 (24) 241602 (2018) DOI: 10.1063/1.5064820 In this paper, we study friction at a very low velocity (37 nm/s), so that we have, in a… Read More
My another unusual article has been published in an open access journal. Nosonovsky M. Cultural implications of biomimetics: changing the perception of living and non-living. MOJ Appl. Bionics Biomech. 2018;2(4):230‒236. http://medcraveonline.com/MOJABB/MOJABB-02-00072.pdf I am cautious with open access journals, since many… Read More
Normally I would not discuss my publications unrelated to my main field of research (mechanical engineering and surface science) in this blog. However, this one, although in a History peer-reviewed journal, deals with the history of mechanics and astronomy. More… Read More
N. Aktaev, A. Fedorets, E. Bormashenko, M. Nosonvosky “Langevin Approach to Modeling of Small Levitating Ordered Droplet Clusters” J. Phys. Chem. Lett., 2018, 9, pp 3834–3838, (Impact Factor = 9.35) DOI: 10.1021/acs.jpclett.8b01693 The Table of Content image shows theoretical predictions… Read More
Prof. Nosonovsky’s article about how modern theories of friction can help engineers is published in the ASME’s “Mechanical Engineering” magazine with the circulation of more than 100,000 hard copies. The article (which was selected for the cover story) discusses such… Read More
While writing about the ordered self-assembled levitating microdroplet clusters, I found that many people (including some reviewers in physics journals) tend to perceive the cluster by analogy with the Leidenfrost effect. In the Leidenfrost effect, a droplet, close to a… Read More
This famous Ancient Egyptian painting on Pharaoh (more accurately, Nomarch) Djehutihotep’s tomb (c. 1880 BCE) entered many tribology textbooks as possible evidence of the use of lubrication in Ancient Egypt. Engineers are quite enthusiastic, although Egyptologists are much more skeptical…. Read More
Our new paper in J. Phys. Chem Lett. (Impact factor = 9.35) deals with a new technique to create a levitating ordered cluster of any arbitrary small number of microdroplets. Before, only large and polydisperse clusters were created, so the… Read More
A researcher from Bangladesh asked me about my “2007 work with a generalized formulation of the Cassie-Baxter and Wenzel equations.” The Wenzel equation was introduced in 1936, and it deals with wetting of a rough surface by a water droplet… Read More
In continuation of my posting from April 20, 2017, “The lowest surface energy is not 6.7 mJ/m2, as it was reported for n-Perfluoroeicosane”. Together with Zhou Chen (who is a graduate student at the Technion and was in my class… Read More
Water is known to form ordered hexagonally symmetric structures (such as snow crystals) in its solid state, however not as liquid or vapor. Typically, fogs and aerosols are composed of randomly moving small droplets lacking any ordered structure. Surprisingly, self-organized… Read More
In a celebrated and often cited (almost 900 citations) paper by Nishino et al. (1999) “The Lowest Surface Free Energy Based on -CF3 Alignment” Langmuir 15:4321-4323, it has been reported that the maximum possible water contact angle with a smooth… Read More
The Kapitsa pendulum (an inverted pendulum on a vibrating foundation), which is stabilized due to fast high frequency vibrations of a foundation, is an example of how vibrations can be substituted by an effective force. A mathematical technique of averaging… Read More
A famous Japanese poem, the “Frog Haiku” composed by Bashô in 1686, says: 古池や 蛙飛び込む 水の音 (“Old pond — a frog jumped in — sound of water”). Splashes of water are fascinating phenomena. An award winning photograph “Milk Drop Coronet”… Read More
The shark skin effect is drag reduction in fluid flow due to a certain design of surface microstructure, namely, due to riblets mimicking shark scale. When a shark swims in water, a special design of riblets on its skin results… Read More
From our same paper, a historical review: “The theory of wetting represented by Equation (1) was formulated for the first time by Thomas Young in 1805 in his essay “On the Cohesion of Fluids” [8]. The essay does not contain… Read More
Surface tension is a fundamental concept in surface physics and chemistry. The most common definition of surface tension is that it is a force acting along a line of unit length parallel to the surface, but perpendicular to the line…. Read More
There is a classical theory of an “entropic” elastic force in an ideal polymer chain, whose shape is modeled as a random walk. The elastic force as a function of the distance between the ends of the chain is calculated… Read More
1. Here we discuss various ideas about wetting, ice adhesion and entropic forces, and how these ideas can be applied to novel superhydrophobic and icephobic concrete: R Ramachandran, M Kozhukhova, K Sobolev, M Nosonovsky Anti-Icing Superhydrophobic Surfaces: Controlling Entropic Molecular Interactions to Design… Read More
R Ramachandran, N Maani, VL Rayz, M Nosonovsky “Vibrations and spatial patterns in biomimetic surfaces: using the shark-skin effect to control blood clotting” Phil. Trans. R. Soc. A 374 (2073), 20160133 M Nosonovsky, B Bhushan “Why re-entrant surface topography is… Read More