Influence of chemical hydrophobizing agents on moisture exchange between pores of sandstone and surroundings

V článku je zhodnocen vliv vybraných typů chemických hydrofobizačních prostředků na dynamiku výměny vlhkosti mezi póry pískovce z lokality Božanov a okolním prostředím. Experiment, jehož výsledky jsou v příspěvku prezentovány, byl založen na hodnocení dynamiky nasákání a odparu vody ze vzorků kamene bez ošetření a po aplikaci hydrofobizačního prostředku. Byly zjištěny významné rozdíly v interakci s vodou u horniny ošetřené látkami na bázi siloxanů a látkou na bázi rozpouštědla s obsahem nanočástic.The paper deals with influence of selected types of chemical hydrophobizing agents on the dynamics of moisture exchange between pores of sandstone from the locality of Bozanov and surroundings. The experiment, whose results are presented, was based on the evaluation of the dynamics of water absorption and evaporation on stone samples without treatment and after application of hydrophobizing agents. Significant differences in interaction between the rock and water were detected for samples treated with agents based on siloxanes and nanoparticles

Influence of thermal loading on interaction between the Moravian greywacke and water

V příspěvku jsou prezentovány výsledky experimentu, zaměřeného na hodnocení dynamiky nasákavosti a odparu vody z pórového systému tzv. moravské droby. Interakce horniny s vodou je zde studována na tepelně neovlivněných horninách a také na horninách vystavených tepelnému namáhání (žíhání) při teplotách 200, 600 a 1000°C. Pozornost je věnována tepelné stabilitě horniny a změnám v interakci horniny s vodou po žíhání.Results of an experiment focused on evaluation of dynamics of water absorption and evaporation from the pore system of the so-called Moravian greywacke are presented in the paper. The interaction between the rock and water has been studied on rock samples before and after their exposure to thermal loading (annealing) at temperatures of 200, 600 and 1000 °C. The attention was paid to thermal stability of the rock and changes in interaction between the rock and water after the rock annealing

On the preparation of precursors and carriers of nanoparticles by water jet technology

Uporaba vodenog mlaza velike brzine proširila se u mnoga područja ljudskog djelovanja zbog njegovih jedinstvenih svojstava. Uz već tradicionalne tehnološke postupke počinje se primjenjivati u usitnjavanju mineralnih čestica. U ovom se radu analizira mogućnost usitnjavanja čestica primjenom abrazivne glave za miješanje koja stvara abrazivni vodeni mlaz velike brzine koji udara u čvrstu okomitu metu od volfram karbida. Čestice filosilikata (tj. sloja silikata) dimenzija kako mikrona tako i submikrona dobivene su ovom metodom. Ovom se metodom izbjegava stvaranje sekundarnih strukturnih defekata suprotno mehaničkim metodama usitnjavanja čestica. Nekoliko tipova mika (muskovit, vermikulit i biotit) i sitnozrnati kaoliniti usitnjeni su primjenom tehnologije vodenog mlaza. Rad se također bavi mogućnostima daljnje promjene dimenzija zrna čestica silikata te korištenja tako pripremljenih čestica kao supstance ili nositelja nanočestica.High-velocity water jet expanded into many fields of human activity due to its unique properties. Besides already traditional technological processes it begins to find its way also to the comminution of mineral particles. The paper analyzes the possibility of particle comminution using an abrasive mixing head used to generate high-velocity abrasive water jet and an impact of the jet to the solid perpendicular target made from tungsten carbide. Phyllosilicate (i.e. layered silicate) particles of both micron and submicron sizes were made by this method. The method avoids the formation of secondary structural defects which is in contrast to mechanical methods of particles comminution. Several types of micas (muscovites, vermiculite and biotite) and fine-grained kaolinites were comminuted using high-velocity water jet technology. The paper also deals with the possibilities of further change of silicate particles grain size and of using such prepared particles as precursors or carriers of nanoparticles

NSR superstring measures in genus 5

Currently there are two proposed ansatze for NSR superstring measures: the Grushevsky ansatz and the OPSMY ansatz, which for genera g<=4 are known to coincide. However, neither the Grushevsky nor the OPSMY ansatz leads to a vanishing two point function in genus four, which can be constructed from the genus five expressions for the respective ansatze. This is inconsistent with the known properties of superstring amplitudes. In the present paper we show that the Grushevsky and OPSMY ansatze do not coincide in genus five. Then, by combining these ansatze, we propose a new ansatz for genus five, which now leads to a vanishing two-point function in genus four. We also show that one cannot construct an ansatz from the currently known forms in genus 6 that satisfies all known requirements for superstring measures.Comment: several correction

Noncritical M-Theory in 2+1 Dimensions as a Nonrelativistic Fermi Liquid

We claim that the dynamics of noncritical string theories in two dimensions is related to an underlying noncritical version of M-theory, which we define in terms of a double-scaled nonrelativistic Fermi liquid in 2+1 dimensions. After reproducing Type 0A and 0B string theories as solutions, we study the natural M-theory vacuum. The vacuum energy of this solution can be evaluated exactly, its form suggesting a duality to the Debye model of phonons in a melting solid, and a possible topological nature of the theory. The physical spacetime is emergent in this theory, only for states that admit a hydrodynamic description. Among the solutions of the hydrodynamic equations of motion for the Fermi surface, we find families describing the decay of one two-dimensional string theory into another via an intermediate M-theory phase.Comment: 47 pages, 1 figure; v2: typos corrected, references adde

Six-dimensional supersymmetric gauge theories, quantum cohomology of instanton moduli spaces and gl(N) Quantum Intermediate Long Wave Hydrodynamics

We show that the exact partition function of U(N) six-dimensional gauge theory with eight supercharges on \u21022 7 S 2 provides the quantization of the integrable system of hydrodynamic type known as gl(N) periodic Intermediate Long Wave (ILW). We characterize this system as the hydrodynamic limit of elliptic Calogero-Moser integrable system. We compute the Bethe equations from the effective gauged linear sigma model on S 2 with target space the ADHM instanton moduli space, whose mirror computes the Yang-Yang function of gl(N) ILW. The quantum Hamiltonians are given by the local chiral ring observables of the six-dimensional gauge theory. As particular cases, these provide the gl(N) Benjamin-Ono and Korteweg-de Vries quantum Hamiltonians. In the four dimensional limit, we identify the local chiral ring observables with the conserved charges of Heisenberg plus W N algebrae, thus providing a gauge theoretical proof of AGT correspondence. \ua9 2014 The Author(s)

Coal tonstein of the Otakar (485) coal seam, the Poruba Mdr , the Ostrava Fm - The Czech part of the Upper Silesian Coal Basin

A new finding of coal tonstein in coal seam Otakar (no. 485) is described in the paper. This tonstein was found in Poruba Mbr, Ostrava Fm (Lower Carboniferous, Arnsbergian, E2b) in the Czech part of the Upper Silesian Cal Basin. Volcanoclastic minerals: quartz, sanidine, mica; authigenic minerals: several forms of kaolinite (vermiform, pseudomorphoses after sanidine and micas), illite-smecite miw - layered structures