Andreev reflection between a normal metal and the FFLO superconductor II: a self-consistent approach

We consider Andreev reflection in a two dimensional junction between a normal metal and a heavy fermion superconductor in the Fulde-Ferrell (FF) type of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state. We assume s-wave symmetry of the superconducting gap. The parameters of the superconductor: the gap magnitude, the chemical potential, and the Cooper pair center-of-mass momentum Q, are all determined self-consistently within a mean-field (BCS) scheme. The Cooper pair momentum Q is chosen as perpendicular to the junction interface. We calculate the junction conductance for a series of barrier strengths. In the case of incoming electron with spin \sigma = 1 only for magnetic fields close to the upper critical field H_{c2}, we obtain the so-called Andreev window i.e. the energy interval in which the reflection probability is maximal, which in turn is indicated by a peak in the conductance. The last result differs with other non-self-consistent calculations existing in the literature.Comment: 15 pages, 6 figures, accepted in Physica

The capsid of small papova viruses contains 72 pentameric capsomeres: direct evidence from cryo-electron-microscopy of simian virus 40

The three-dimensional structure of the simian virus 40 capsid is remarkably similar to the structure of the polyoma empty capsid. This similarity is apparent despite striking differences in the methods used to determine the two structures: image analysis of electron micrographs of frozen-hydrated samples (SV40 virions) and an unconventional x-ray crystallographic analysis (polyoma empty capsids). Both methods have clearly resolved the 72 prominent capsomere units which comprise the T = 7d icosahedral capsid surface lattice. The 12 pentavalent and 60 hexavalent capsomeres consist of pentameric substructures. A pentameric morphology for hexavalent capsomeres clearly shows that the conserved bonding specificity expected from the quasi-equivalence theory is not present in either SV40 or polyoma capsids. Determination of the SV40 structure from cryo-electron microscopy supports the correctness of the polyoma structure solved crystallographically and establishes a strong complementarity of the two techniques. Similarity between the SV40 virion and the empty polyoma capsid indicates that the capsid is not detectably altered by the loss of the nucleohistone core. The unexpected pentameric substructure of the hexavalent capsomeres and the arrangement of the 72 pentamers in the SV40 and polyoma capsid lattices may be characteristic features of all members of the papova virus family, including the papilloma viruses such as human wart and rabbit papilloma

Shaft voltages and currents in large power induction motors of heading machine

The paper presents results of researches aimed at bearing faults detection in the high power induction motors. In the chapter 2 is presented description of laboratory stand. In the chapter 3, on the figures from 2 to 9 are shown different kinds of bearing damages arising in considered motors. In the chapter 4 is presented influence of supply voltage unbalance on the value of shaft currents and voltages. The figure 10 presents diagram of measuring system. On the figures 12, 13 and 14 are presented waveforms of shaft voltages and currents as well as their Fourier transforms. In the chapter 5 is presented influence of number of motor start-ups on the value of bearing current. On the figure 17 are presented waveforms of shaft voltages and currents. Conclusions drawn from laboratory researches are presented in chapter 6

Equivalent circuits and diagnostics of bushing insulator of transformer

This article presents the construction and diagnostics of high-voltage, paper-oil Cushing insulator in porcelain body. Such insulators are used in power transformers. Diagnostics of this insulators is based either on measurements of tgδ and of capacity C or on measurement of summary leakage current. Electrical equivalent circuits of the diagnosed insulation system are being presented. Moreover it is shown why this type of diagnostics is unreliable. More reliable diagnostic method is the measurements of the oil (DGA analysis).W artykule przedstawiono budowę i diagnostykę izolatora przepustowego wysokiego napięcia papierowo-olejowego w osłonie porcelanowej. Izolatory tego typu są stosowane w transformatorach energetycznych. Diagnostyka izolatorów bazuje na pomiarach tgδ i pojemności C bądź na pomiarze sumarycznego prądu upływu. Przedstawiono elektryczne schematy zastępcze diagnozowanego układu izolacyjnego i wykazano dlaczego tego typu diagnostyka jest mało wiarygodna. Wskazano, że bardziej wiarygodną diagnostyką jest badanie oleju (analiza DGA)

Damage of the bushing insulator and the transformer’s breakdown

This article presents two examples of the fire in transformers, caused by the 400 kV and 220 kV paper-oil-type insulators breakdown. The bushing insulators’ breakdown was caused by the partial discharges insi de of the paper insulation, which leaded to insulator’s explosion, phase short-circuit fault and also to fire of the transformers. An example is also shown in this article of the power transformer with dry-type bushing insulators, which seems to be safer in the exploitation.W artykule przedstawiono dwa przykłady pożaru transformatorów spowodowane awarią izolatorów przepustowych papierowo-olejowych 400 kV i 220 kV. Przyczyną uszkodzenia izolatorów przepustowych były wyładowania niezupełne wewnątrz izolacji papierowej, które doprowadziły do eksplozji izolatora, zwarcia fazowego i pożaru transformatorów. Przedstawiono przykład transformatora z izolatorami przepustowymi suchymi, które wydają się być bardziej bezpieczne w eksploatacji

The capsid of small papova viruses contains 72 pentameric capsomeres: direct evidence from cryo-electron-microscopy of simian virus 40.

The three-dimensional structure of the simian virus 40 capsid is remarkably similar to the structure of the polyoma empty capsid. This similarity is apparent despite striking differences in the methods used to determine the two structures: image analysis of electron micrographs of frozen-hydrated samples (SV40 virions) and an unconventional x-ray crystallographic analysis (polyoma empty capsids). Both methods have clearly resolved the 72 prominent capsomere units which comprise the T = 7d icosahedral capsid surface lattice. The 12 pentavalent and 60 hexavalent capsomeres consist of pentameric substructures. A pentameric morphology for hexavalent capsomeres clearly shows that the conserved bonding specificity expected from the quasi-equivalence theory is not present in either SV40 or polyoma capsids. Determination of the SV40 structure from cryo-electron microscopy supports the correctness of the polyoma structure solved crystallographically and establishes a strong complementarity of the two techniques. Similarity between the SV40 virion and the empty polyoma capsid indicates that the capsid is not detectably altered by the loss of the nucleohistone core. The unexpected pentameric substructure of the hexavalent capsomeres and the arrangement of the 72 pentamers in the SV40 and polyoma capsid lattices may be characteristic features of all members of the papova virus family, including the papilloma viruses such as human wart and rabbit papilloma

Reconstruction of the three-dimensional structure of simian virus 40 and visualization of the chromatin core.

The three-dimensional structure of the capsid and the nucleohistone core of simian virus 40 (SV40) has been reconstructed by image analysis of electron micrographs of frozen hydrated samples. The 72 prominent capsomere units that comprise the T = 7d icosahedral surface lattice of the capsid are clearly resolved. Both the pentavalent and hexavalent capsomeres appear with pentameric substructure, indicating that bonding specificity in the shell is not quasi-equivalent. There is a remarkable similarity between the structure of the SV40 virion capsid and the structure reported for the polyoma empty capsid. This result establishes that (i) the unexpected pentameric substructure of the hexavalent capsomeres is also present in virions and (ii) the arrangement of the 72 pentamers in the capsid lattice may be a characteristic feature of the entire papova family of viruses. The center of the SV40 reconstruction reveals electron density corresponding to the nucleohistone core. This density is smeared, suggesting that the minichromosome is not organized with icosahedral symmetry matching the capsid symmetry. The visualization of the virion chromatin provides a basis for invoking new models for the higher order structure of the encapsidated minichromosome