Research of Geopolymer Foam Concrete on the Base of the Wastes Produced By Kemerovo Heat and Power Enterprises

The article shows the results of the research on geopolymer foam concrete production on the base of the wastes of Kemerovo heat and power enterprises. Relationships between the compression strength and average density of geopolymer foam concrete and the alkaline activator amount, alkaline concentration, foaming agent amount and duration of the blend mechanical activation were determined. It was found out that being in its optimal composition the material obtained has strength 2.0-3.5 MPa under density from 350 up to 500 kg/m3. Infusion of the developed construction material on the basis of the industrial wastes will allow to change more expensive construction materials on the cement base and provide the utilization of the industrial wastes

Continuous-time quantum walk on integer lattices and homogeneous trees

This paper is concerned with the continuous-time quantum walk on Z, Z^d, and infinite homogeneous trees. By using the generating function method, we compute the limit of the average probability distribution for the general isotropic walk on Z, and for nearest-neighbor walks on Z^d and infinite homogeneous trees. In addition, we compute the asymptotic approximation for the probability of the return to zero at time t in all these cases.Comment: The journal version (save for formatting); 19 page

Phase heterogeneity of acetone solutions of cellulose nitrate

NMR and turbidity points were used to study temperature transitions in concentrated solutions of CN with a nitrogen content of 13·5 and 14·01%. Turbidity curves show two regions where light scattering changes suddenly. The critical concentration, above which these transitions are observed, is close to that predicted by the Flory theory for a narrow two-phase region. The transitions observed are accompanied by unusual changes in the drop of free induction of CN and transverse relaxation time of solvent molecules. Based on these results a conclusion was drawn about the LC form of transitions taking place. © 1988

Electrochemical reduction of bifunctional organic compounds Communication 5. Kinetics of the rearrangement of endiols in the reduction of paradiacetylbenzene and terephthalic aldehyde

1. The kinetics of the rearrangement of endiols to a monocarbonyl compound in the reduction of p-diacetylbenzene and terephthalic aldehyde was studied. 2. The equilibrium constants of the preceding reaction of hydration of terephthalic aldehyde was measured. © 1972 Consultants Bureau, a division of Plenum Publishing Corporation

Rates of convergence for empirical spectral measures: a soft approach

Understanding the limiting behavior of eigenvalues of random matrices is the central problem of random matrix theory. Classical limit results are known for many models, and there has been significant recent progress in obtaining more quantitative, non-asymptotic results. In this paper, we describe a systematic approach to bounding rates of convergence and proving tail inequalities for the empirical spectral measures of a wide variety of random matrix ensembles. We illustrate the approach by proving asymptotically almost sure rates of convergence of the empirical spectral measure in the following ensembles: Wigner matrices, Wishart matrices, Haar-distributed matrices from the compact classical groups, powers of Haar matrices, randomized sums and random compressions of Hermitian matrices, a random matrix model for the Hamiltonians of quantum spin glasses, and finally the complex Ginibre ensemble. Many of the results appeared previously and are being collected and described here as illustrations of the general method; however, some details (particularly in the Wigner and Wishart cases) are new. Our approach makes use of techniques from probability in Banach spaces, in particular concentration of measure and bounds for suprema of stochastic processes, in combination with more classical tools from matrix analysis, approximation theory, and Fourier analysis. It is highly flexible, as evidenced by the broad list of examples. It is moreover based largely on "soft" methods, and involves little hard analysis

Plasma assisted-MBE of GaN and AlN on graphene buffer layers

The possibility of using chemical vapor deposition (CVD) graphene as a 2D buffer layer for epitaxial growth of III-nitrides by plasma assisted-MBE on amorphous substrates (SiO2 prepared by thermal oxidation of Si wafer) was investigated. The comparative study of graphene-coated parts of the wafers and the parts without graphene was carried out by scanning electron microscopy and X-ray diffractometry. It was shown that epitaxial GaN and AlN films with close to 2D surface morphology can be obtained by plasma assisted-MBE on amorphous SiO2 substrates with a multilayer graphene buffer using the HT AlN nucleation layer

Possibility of determining the graphene doping level using Raman spectra

Raman spectroscopy was used to study the structure of graphene synthesized from methane by chemical vapor deposition at atmospheric pressure and transferred to a SiO2/Si substrate using various transfer and polymer removal methods. It was found that the dependences of the 2D peak positions on the G peak positions of the studied samples were well-behaved linear functions with slopes of ~2.2 that suggested the existence of biaxial stress in the graphene. It was discovered that the doping in the samples changed