Strength properties and aging of sheet glass-reinforced plastics under various climatic conditions

Data on the variation of the physicomechanical properties of sheet glass-reinforced plastics exposed over a four-year period to different climatic conditions are reported. Polyester and phenolic laminates were exposed to the climates of Moscow and Batum either in the open air or in unheated warehouses. The tensile and bending strengths were taken as the principal indicators of changes in the mechanical properties of the materials. The property fluctuations are more considerable under humid subtropical conditions (Batum).All-Union Scientific-Research Institute of Glass-Reinforced Plastics and Fiberglass, Moscow Region. Translated from Mekhanika Polimerov, No. 3, pp. 554–558, May–June, 1971.     

Isothermal relaxation current in a dielectric with partially blocking contacts

The continuity and Poisson's equations are solved numerically for a dielectric with partially blocking electrodes in the nonsteady case. The distribution of the mobile-charge-carrier concentration and the electric field strength inside the dielectric is obtained at various times after the potential source is switched on. The time dependence of the isothermal current and the emf of high-voltage polarization of the dielectric with a single type of mobile charge carriers at different values of the contact current is calculated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 12–16, September, 1985.     

The eighth virial coefficient of four- and five-dimensional hard hyperspheres

The eighth virial coefficient for hard hyperspheres is calculated by Monte Carlo techniques. It is found that B8/B(7)2=0.000 274+/-0.000 014 and -0.000 115+/-0.000 012 in four and five dimensions, respectively. The results are in good agreement with the findings of Clisby and McCoy (e-print arXiv:cond-mat0410511), and confirm that B8 is negative in five dimensions.     

The possibility of using a semiconductor thermal probe to investigate the power flow distribution in waveguides

Conclusions

1. The temperature profile of an absorbing film for a given microwave power flux distribution has been considered.
2. The conditions under which agreement is found between the temperature relief and the flux distribution has been clarified.
3. An experimental investigation has been carried out of the temperature profile in a matched film for the TE₁₀ mode.
4. The possibility of using a semiconductor thermal probe to investigate the microwave power flux distribution has been demonstrated.

     

Two body correlations between negative pions in pp interactions at 69 GeV/c

Correlations between two π^? in pp interactions at 69 GeV/c are presented in terms of longitudinal and transversal variables. The dominant feature is the existence of a strong shortrange positive correlation between the two π^? in the central region.