When Debye length is comparable or larger than the distance between two identical particles, the overlapping among the particles double-layers can play an important role in their interactions. This paper presents a theoretical analysis of the interaction among two identical particles with overlapped double-layers. We particularly focus on the effect of a Stern electro static condition from line...

The behavior of mesoscopic particles dissolved in a dilute solution of long, flexible, and nonadsorbing polymer chains is studied by field-theoretic methods. For spherical and cylindrical particles the solvation free energy for immersing a single particle in the solution is calculated explicitly. Important features are qualitatively different for self-avoiding polymer chains as compared with id...

This note considers variations on the theme of a solenoid magnet (i.e., a magnet whose field has axial symmetry) as a lens for charged particles. A related problem has been posed in [1]. Recall that if a device is to be a lens with optic axis along the z axis in a cylindrical coordinate system (r, φ, z), then as particles leave the device they must have no azimuthal momentum, Pφ = 0, and their ...

Preparations of highly purified tetrodotoxin-binding protein (sodium channel) from the electric organ of the eel Electrophorus electricus were examined in negatively stained preparations. Structures observed in preparations exhibiting the highest tetrodotoxin binding tended to aggregate into ordered clusters with a unique ribbon-like conformation. The individual particles of these aggregates ar...

Recent experiments with single biological nanopores, as well as single-molecule fluorescence spectroscopy and pulling studies of protein and nucleic acid folding raised a number of questions that stimulated theoretical and computational investigations of barrier crossing dynamics. The present paper addresses a closely related problem focusing on trajectories of Brownian particles that escape fr...

The hemolytic activity of fibrous asbestos varieties and of fibrous or granular silica dust can be markedly reduced by adsorption of polymers. Polyanions exert a specific action on asbestos, particularly chrysotile, whereas silica is inactivated by nonionic polymers. A high degree of reduction of the lytic action by comparatively small amounts of the antagonistic polymers can be demonstrated af...

Trichomonas vaginalis is a flagellated, parasitic protozoan that inhabits the urogenital tract of humans. Some isolates of T. vaginalis are infected with a double-stranded RNA (dsRNA) virus, which was described in the literature as homogeneous icosahedral viral particles with an isometric symmetry and 33 nm in diameter. This study examined in detail the viral particles in T. vaginalis isolate 3...

The separation of cells or particles from solution has traditionally been accomplished with centrifuges or by sedimentation; however, many particles have specific densities close to unity, making buoyancy-driven motion slow or negligible, but most cells and particles carry surface charges, making them ideal for electrophoretic separation. Both buoyancy-driven and electrophoretic separation may ...

Predictions of electrostatic double-layer interaction forces between two similarly charged spherical colloidal particles inside an infinitely long "rough" capillary are presented. A simple model of a rough cylindrical surface is proposed, which assumes the capillary wall to be a periodic function of axial position. The periodic roughness of the wall is characterized by the wavelength and amplit...

The neutron charge form factor G En (q) is determined from an analysis of the deuteron quadrupole form factor F C2 (q) data. Recent calculations, based on a variety of different model interactions and currents, indicate that the contributions associated with the uncertain two-body operators of shorter range are relatively small for F C2 (q), even at large momentum transfer q. Hence, G En (q) ca...