Polyhedral foams offer large gas-liquid interfacial area associated with a small amount of liquid. Therefore, if a solute adsorbs preferentially at the interface, the concentration of the solute in the foam will be greater than in the solution from which the foam has been generated. This effect provides a simple method of concentrating materials which have a tendency to adsorb on the gas-liquid interface. This is particularly relevant to biomaterials like whole cells, proteins, enzymes etc., which are surface active and are present in low concentrations in the broth. Foam separation has therefore attracted considerable attention, and several reports exist in literature on concentrating cells, proteins and enzymes using foams. Foam separation is based on the difference in surface activity of the components to be separated. A surface active molecule consists of a lyophobic and a lyophilic group. (As water is commonly used as a solvent, the lyophilic and lyophobic groups are called hydrophilic and hydrophobic groups, respectively). When dissolved in a solvent, the presence of lyophobic groups in the interior of the solvent distorts the solvent liquid structure, thereby increasing the free energy of the system.

Under the right conditions, a moving sphere may successfully enter, and leave, a soap bubble without rupturing that bubble. The physics behind this phenomena are not well understood, nor the limiting factors (such as sphere size, speed, etc.). This work, investigating this phenomenon using high speed photography, has produced several results which are presented. First, several distinct regimes, noted while photographing the interactions between the spheres and the bubbles, are classified and discussed. Next a probabilistic examination of the soap bubbles rupture by the moving spheres is presented. Then a conjecture for the limiting sphere sizes and speeds is presented. And finally some interesting phenomena, noted in the course of this investigation, are presented and discussed.

This paper analyzes the political dimensions surrounding visual and literary allusions to soap bubbles. Traditionally, iconographic studies consider soap bubbles within the history of northern Baroque vanitas, attaching to bubbles notions of ephemerality and transience. Building on these interpretations, eighteenth- and nineteenth-century French artists and writers created a complex metaphor for soap bubbles that relied on their impermanence and fragility, as well as their illusory nature. By coupling the earliest conceptual meanings of soap bubbles with their almost imperceptible formal properties, the bubble blower came to symbolize deceivers, or figures creating illusions or delusions. Eventually, this transformed vanitas symbolism became harnessed to political critiques and representative of chimerical assertions of papal authority, calumny, and false promises of liberal reform. I not only describe the alternative meanings associated with soap bubbles in eighteenth- and nineteenth-century France, but also I situate Edouard Manet's Les Bulles de savon (1867) within this trajectory. While most scholars interpret Manet's painting and accompanying prints as a continuation of, and legacy to, the Dutch vanitas tradition, I illustrate how the artistic and political milieu in which Manet worked mirrored earlier criticisms employing allusions to bubbles. / Art History

This diploma thesis deals with problem of design and calculation of membrane structure of stadium roof. This is a complex engineering problem, which includes many partial problems: finding of initial form of membrane, statically and architecturally suitable arrangement of catenaries, economical solution of boundary conditions (foundations). All components affect each other and cannot be dealt without mutual coordination. It always greatly depends on the experience and intuition of engineer who design such structure. Task which cannot be resolved according to the theory of the first order. Equilibrium forces on the deformed structure, which in many projected structures gives satisfactory results, did not correspond to reality. It is therefore necessary to consider equilibrium of forces on the deformed structure according to the theory of large deformations. Diploma thesis was entered with regard to the intention of the companies Ing. Software Dlubal s.r.o. and FEM consulting s.r.o., working together to develop software RFEM. These companies plan to complement this program system with a module MEMBRANE for searching of initial shapes of membrane structures. This work is a contribution to the creation of this module.