The structural development of linear canonical transforms

Physics of Atomic Nuclei - We consider that the simultaneous development of the theory of linear canonical integral transforms among two quite distinct scientific communities, provides an...     

Development of novel backwash cleaning technique for reverse osmosis in reclamation of secondary effluent

The objective of the study was to further develop a novel cleaning technique for reverse osmosis in reclamation of municipal secondary effluent. This technique is a new backwash method via direct osmosis (DO) by intermittent injection of the high salinity (HS) solution without stopping of high pressure pump and it is environment and membrane friendly technique. In the study, DO-HS trials were carried out with a UF-RO pilot system which was operated on site with the secondary treated effluent as the raw feed. Different operating conditions for DO-HS treatment in the actual process were investigated. It was found that the operation for implementation of the DO-HS cleaning technique developed was easy. For the first time, the actual profiles of HS concentration, DO backwash flow rate, brine flow rate and permeate pressure during DO-HS treatment have been demonstrated. It was observed that turbidity of the brine stream during DO-HS treatment at 3 NTU was 5 times higher than that before DO-HS treatment. The results from this study have confirmed the previous hypothesis with DO-HS treatment that there would be a strong driving force for DO backwash to lift and sweep the foulants from the membrane surface which would be carried over to the brine. The optimal plant operating conditions in terms of RO feed flow rate, HS concentration and HS injection time are ready for the DO-HS method to be adopted and validated in a long-term continuous plant operation.     

Influence of Ionizing Radiation on the Properties of a Nanodispersed PdO/CeO<Subscript>2</Subscript> Catalyst in the Reaction of Low-Temperature Carbon Monoxide Oxidation

The effect of electron-beam irradiation on the catalytic properties of PdO/CeO₂ has been examined. It has been found that irradiation in the range of 15–30 kGy results in an increase in the concentration of the radical anion [O^?], thereby enhancing the catalytic activity of PdO/CeO₂.     

Specific features of hopping conduction in bismuth-containing oxide layered ceramics

The dynamic conduction of bismuth-containing oxide layered ceramics of the composition Sr₂Bi₂TiNb₂O₁₂ is investigated in a weak alternating field at frequencies of 0.5–500 kHz in the temperature range 300–700 K. It is demonstrated that the high-temperature conduction can be adequately described in terms of theoretical concepts using the effective medium method and corresponds to two-dimensional hopping transfer. The concentration of nodes in the system through which charge-carrier hopping occurs is estimated.     

Degrees of symmetry in quantum field theories

A hierarchy of possible symmetries in quantum field theory is defined, which reaches from a purely mathematical invariance to the conventional physical invariance, including the commonly discussed type of spontaneously broken symmetry (SBS). It is shown that one type of SBS, which is usually not considered, naturally leads to theories with an algebra of non-conserved currents and a non-linearly transforming phenomenological Lagrangian. An exactly solvable model is given and some general remarks are made.     

Peculiarities of the reaction of C5-dehydrocyclization of n-heptane under conditions of a pulsed system

Russian Chemical Bulletin -