scholarly journals A Study of Possible Reasons of the Damage by Electric Current of Traction Induction Motors Bearings of Electric Trains Lastochka and the Ways to Prevent This

2021 ◽  
Vol 2096 (1) ◽  
pp. 012001
Author(s):  
M Pustovetov
Keyword(s):  
Electric Current ◽  
High Frequency ◽  
Induction Motors ◽  
Electrical Breakdown ◽  
The Other ◽  
Technical Solution ◽  
Insulation Coating ◽  
Rolling Elements ◽  
Current Flows ◽  
Frequency Current

Abstract There is a problem of damage of bearings of traction induction motors of electric trains Lastochka by electric current. Based on the fact that the bearings have a ceramic insulation coating, and the cases of its electrical breakdown is not fixed, the authors put forward a version that a high-frequency current flows through the bearing as through an electric capacitance. The analysis show that the cause of the current can be a radio standard GSM-R. The proposed technical solution against the damage of bearings: the use of grounding shaft rings, replace the bearings on the other with ceramic rolling elements, arrangement of separate high-frequency grounding for the GSM-R antenna.

scholarly journals Effects of High-Frequency Electrical Stunning Current Intensities on Pre-Slaughter Stunning Stress and Meat Lipid Oxidation in Geese

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2376
Author(s):  
Lei Xu ◽  
Haiming Yang ◽  
Xiaoli Wan ◽  
Xin Zhang ◽  
Zhi Yang ◽  
...  
Keyword(s):  
Lipid Oxidation ◽  
High Frequency ◽  
The Other ◽  
Current Intensity ◽  
Control Group ◽  
Breast Meat ◽  
Maximum Serum ◽  
A Current ◽  
Frequency Current ◽  
Total Superoxide Dismutase

Intensive slaughtering with electrical stunning (ES) is replacing traditional manual slaughtering of geese in China. This study aimed to assess stunning stress and meat lipid oxidation in geese stunned by high-frequency current intensities. Forty male Yangzhou geese, 92 days old, were randomly allocated into five treatments with eight replicates per treatment. The geese in the control group were not stunned, while the other birds were stunned by alternating current (AC) in a water bath. Each bird received a current intensity of 20 mA (E20mA), 40 mA (E40mA), 70 mA (E70mA), or 100 mA (E100mA) for 10 s at 500 Hz. The gene expression of c-jun N-terminal kinase 1 tended to decrease in the E40mA birds (p = 0.08). Stunning with 40 mA resulted in the maximum serum uric acid and urea among the ES groups and decreased serum adrenocorticotropin and creatine kinase (p < 0.01) compared with 70 mA and 100 mA. Increasing the current intensity reduced the diphenylpicrylhydrazyl free radical elimination ability and total-superoxide dismutase linearly in goose breast meat at d 2 and in thigh meat at d 0 (all p < 0.01). Stunning geese with 40 mA at 500 Hz for 10 s could alleviate stunning stress and meat lipid oxidation.

Electric currents in the ionosphere - Ionization drift due to winds and electric fields

1953 ◽  
Vol 246 (913) ◽  
pp. 306-320 ◽  
Keyword(s):  
Electric Field ◽  
Electric Current ◽  
Electric Fields ◽  
Body Force ◽  
Surrounding Medium ◽  
The Other ◽  
Electric Currents ◽  
Vertical Drift ◽  
Meteor Trails ◽  
Current Flows

An analysis is made of the drift velocity of the (neutral) ionization in a uniform ionosphere under the influences of an electric field and/or atmospheric wind. It is shown that this drift of ionization produces the Ampere body force on the medium; the electric current flows perpendicular to the drift. The motion of a cylinder of ionization, of density differing from the surrounding medium, is then studied. It is found that the motion is electrodynamically stable, but unstable hydrodynamically, if Hall conductivity is appreciable. In the latter event there is rapid accretion of (neutral) ionization on one side of the cylinder, depletion on the other. It is suggested that this is the origin of sporadic E ( E 5 )ionization, and is likely to be an important factor in the production of the long-enduring meteor trails detected by radio methods. Formulae are derived for the horizontal and vertical drift of ionization at all latitudes in a thin ionosphere in which vertical electric currents are prohibited by polarization. Graphs are given which permit derivation of the true wind or field in a given region of the ionosphere from experimental observations of the drift velocities.

scholarly journals STUDIES IN HYPERTHERMIA INDUCED BY THE HIGH FREQUENCY ELECTRIC CURRENT

1930 ◽  
Vol 85 (3) ◽  
pp. 675-686
Author(s):  
Fritz Bischoff ◽  
H.J. Ullmann ◽  
Elsie Hill ◽  
M. Louisa Long
Keyword(s):  
Electric Current ◽  
High Frequency

scholarly journals Chance or Necessity—The Fungi Co−Occurring with Formica polyctena Ants

Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 204
Author(s):  
Igor Siedlecki ◽  
Michał Gorczak ◽  
Alicja Okrasińska ◽  
Marta Wrzosek
Keyword(s):  
Molecular Identification ◽  
High Frequency ◽  
Its Rdna ◽  
The Other ◽  
Formica Polyctena ◽  
Ant Nests ◽  
Mutualistic Fungi ◽  
The Tropics ◽  
High Diversity ◽  
Better Than

Studies on carton nesting ants and domatia−dwelling ants have shown that ant–fungi interactions may be much more common and widespread than previously thought. Until now, studies focused predominantly on parasitic and mutualistic fungi–ant interactions occurring mostly in the tropics, neglecting less−obvious interactions involving the fungi common in ants’ surroundings in temperate climates. In our study, we characterized the mycobiota of the surroundings of Formica polyctena ants by identifying nearly 600 fungal colonies that were isolated externally from the bodies of F. polyctena workers. The ants were collected from mounds found in northern and central Poland. Isolated fungi were assigned to 20 genera via molecular identification (ITS rDNA barcoding). Among these, Penicillium strains were the most frequent, belonging to eight different taxonomic sections. Other common and widespread members of Eurotiales, such as Aspergillus spp., were isolated very rarely. In our study, we managed to characterize the genera of fungi commonly present on F. polyctena workers. Our results suggest that Penicillium, Trichoderma, Mucor, Schwanniomyces and Entomortierella are commonly present in F. polyctena surroundings. Additionally, the high diversity and high frequency of Penicillium colonies isolated from ants in this study suggest that representatives of this genus may be adapted to survive in ant nests environment better than the other fungal groups, or that they are preferentially sustained by the insects in nests.

Normal Synaptonemal Complex and Abnormal Recombination Nodules in Two Alleles of the Drosophila Meiotic Mutant mei-W68

Genetics ◽  
2003 ◽  
Vol 163 (4) ◽  
pp. 1337-1356 ◽  
Author(s):  
Adelaide T C Carpenter
Keyword(s):  
Electron Microscopy ◽  
Synaptonemal Complex ◽  
High Frequency ◽  
Serial Section ◽  
The Other ◽  
Wild Type ◽  
Recombination Nodules ◽  
Section Electron ◽  
Serial Section Electron Microscopy ◽  
Section Electron Microscopy

Abstract The meiotic phenotypes of two mutant alleles of the mei-W68 gene, 1 and L1, were studied by genetics and by serial-section electron microscopy. Despite no or reduced exchange, both mutant alleles have normal synaptonemal complex. However, neither has any early recombination nodules; instead, both exhibit high numbers of very long (up to 2 μm) structures here named “noodles.” These are hypothesized to be formed by the unchecked extension of identical but much shorter structures ephemerally seen in wild type, which may be precursors of early recombination nodules. Although the mei-W68L1 allele is identical to the mei-W681 allele in both the absence of early recombination nodules and a high frequency of noodles (i.e., it is amorphic for the noodle phene), it is hypomorphic in its effects on exchange and late recombination nodules. The differential effects of this allele on early and late recombination nodules are consistent with the hypothesis that Drosophila females have two separate recombination pathways—one for simple gene conversion, the other for exchange.

scholarly journals Fracture of a gas pipeline manufactured by high frequency current welding

2021 ◽  
Vol 1023 ◽  
pp. 012003
Author(s):  
A A Alexeev ◽  
A S Syromyatnikova ◽  
A M Bolshakov ◽  
A R Ivanov
Keyword(s):  
High Frequency ◽  
Gas Pipeline ◽  
High Frequency Current ◽  
Frequency Current
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