Valence Shell Electron-Pair Repulsion (VSEPR) theory has been regarded for decades as a highly successful, albeit nonquantitative model used to predict molecular geometries. 1 The VSEPR model bases its conjectures on the simple modeling of repulsive forces between electron pairs surrounding a central atom. As two charges of the same sign—positive or negative—are brought closer together, each ch...

Abstract Membrane filtration is vital in our daily lives to extract fresh water from contaminated water. However, membrane suffering fouling, which induced by accumulations of particles on surface. Due the hydraulic field and electrical (from functional groups membranes) near surface, particle will be exerted different forces. The intermolecular forces such as Lateral lift force, Brownian shear...

Water suspensions of in-organic (metals and oxides) and organic nano-objects (chitozan and collagen) were subjected to the treatment of direct and alternative electrical fields. In addition to quasi-periodical spatial patterning resonance-like performance of spatial distributions of these suspensions has been found at low frequencies of alternating electrical field. These resonances are explain...

The transport of bacterial strain DA001 was examined in packed quartz sand under a variety of environmentally relevant ionic strength and flow conditions. Under all conditions, the retained bacterial concentrations decreased with distance from the column inlet at a rate that was faster than loglinear, indicating that the deposition rate coefficient decreased with increasing transport distance. ...

It is well known that the Casimir force between two half-spaces is dictated by their electromagnetic properties. In particular, when one of the half-spaces is mainly metallic or dielectric and the other is mainly magnetic, it is possible to show that the force is repulsive. This has attracted lots of interest towards the study of metamterials (MMs) in the context of Casimir effect, as their mag...

Silicon clusters were produced by gas aggregation in vacuum and co-deposited with water vapour onto a cold target where the water vapour froze. Melting of the ice yielded fluorescent silicon nanoparticles suspended in water which were investigated by photoluminescence spectroscopy (PL) and atomic force microscopy (AFM). The PL spectrum showed a prominent band at 420 nm and other, less intense b...

The present paper is related to a talk presented during the Symposium on Coherent Control and Ultracold Chemistry held during the Sixth Congress of the International Society for Theoretical Chemical Physics (ISTCP-VI, July 2008). The talk was entitled ”Electronic structure properties of alkali dimers and trimers. Prospects for alignment of ultracold molecules”. Here we report on the electrostat...

Chromatin looping is a major epigenetic regulatory mechanism in higher eukaryotes. Besides its role in transcriptional regulation, chromatin loops have been proposed to play a pivotal role in the segregation of entire chromosomes. The detailed topological and entropic forces between loops still remain elusive. Here, we quantitatively determine the potential of mean force between the centers of ...

We use dissipative particle dynamics (DPD) and molecular models to simulate interacting oil/water/surfactant interfaces. The system comprises sections of two emulsion droplets separated by a film. The film is in equilibrium with a continuous phase, in analogy with the surface force apparatus. This is achieved by combining DPD with a Monte Carlo scheme to simulate a muVT ensemble. The setup enab...

This paper presents measurements, using the surface force balance (SFB), of the normal and shear forces in aqueous solutions between polyelectrolyte layers grown directly on mica substrates (grafted-from). The grafting-from was via surface-initiated atom transfer radical polymerization (surface-initiated ATRP) using a positively charged methacrylate monomer. X-ray reflectometry measurements con...