973 research outputs found
Phase equilibria and thermodynamic properties of oxide systems on the basis of rare earth, alkaline earth and 3d-transition (Mn, Fe, Co) metals. A short overview of
Review is dedicated studies of phase equilibria in the systems based on rare earth elements and 3d transition metals. It’s highlighted several structural families of these compounds and is shown that many were found interesting properties for practical application, such as high conductivity up to the superconducting state, magnetic properties, catalytic activity of the processes of afterburning of exhaust gases, the high mobility in the oxygen sublattice and more
Генноредаговані рослини: досягнення та перспективи (огляд)
Мета. Проаналізувати сучасну ситуацію з поліпшенням сільськогосподарських культур технологіями редагування генів. Результати. Проаналізовано нинішню ситуацію зі створенням сортів рослин за допомогою технологій редагування генів. Натепер редагування геному застосовано до широкого спектра культур, зокрема пшениці, ячменю, кукурудзи, бобових, сої, ріпаку, томатів, цикорію, різних садових рослин, фруктових і лісових дерев, водоростей. Практичне впровадження цих технологій продемонстровано на прикладі генів, пов’язаних із забезпеченням толерантності до дії високих і низьких температур. Також наведено приклади комерціалізованих генноредагованих рослин. Висновки. Завдяки внеску в підвищення врожайності, стійкості проти хвороб і шкідників, а також біофортифікації продовольчих культур редагування генів має значні перспективи та, безумовно, є технологією, що дає змогу створювати поліпшені сорти сільськогосподарських рослин
Prompt neutrino fluxes from atmospheric charm
We calculate the prompt neutrino flux from atmospheric charm production by
cosmic rays, using the dipole picture in a perturbative QCD framework, which
incorporates the parton saturation effects present at high energies. We compare
our results with the next-to-leading order perturbative QCD result and find
that saturation effects are large for neutrino energies above 10^6 GeV, leading
to a substantial suppression of the prompt neutrino flux. We comment on the
range of prompt neutrino fluxes due to theoretical uncertainties.Comment: 13 pages with 11 figures; expanded discussion, added references,
version to be published in Phys. Rev.
The Results of Plant Monitoring in the Semistozhki Area of Stavropol Region
Preserving biodiversity is a global problem that was reflected in the Convention on Biological Diversity which appeared in 1992. The adoption of the Convention was an answer to the intensified problem of a significant reduction in the diversity of genetic resources. Botanical gardens are the main centres for preserving the biodiversity of plants that solve the problem of preserving the gene pool. One of the main tasks of botanical gardens is to monitor plant populations in their natural habitats in situ. This paper describes the monitoring of the current state of peonies and sedges in the Semistozhki area of the Andropov district in the Stavropol region. The research determines the growing locations and the belongingness of species to plant associations in the vegetation variety of the Stavropol region. It also determines the species that may be treated as rare due to their limited distribution area. The territory is marked by the presence of Paeonia tenuifolia L., which is a tertiary relict, and Paeonia biebersteiniana Rupr., which is subendimic for Stavropol region. Rear species with low numbers that are not threatened by grave danger of extinction are also present. Carex hordeistichos Vill. and c. otrubae Podp. species in the area are small in number. Their populations in the area are inadequate with young, vegetative and strong specimens lacking. The limiting factors are represented by human agricultural activities. Several specimens of a narrow-leaved peony of pink colour and a big number of petals were planted on an experimental stretch of the botanical garden to continue the analysis ex-situ
Highly mobile carriers in orthorhombic phases of iron-based superconductors FeSeS
The field and temperature dependencies of the longitudinal and Hall
resistivity have been measured for FeSeS (x=0.04, 0.09 and
0.19) single crystals. The sample FeSeS does not show a
transition to an orthorhombic phase and exhibits at low temperatures the
transport properties quite different from those of orthorhombic samples. The
behavior of FeSeS is well described by the simple two
band model with comparable values of hole and electron mobility. In particular,
at low temperatures the transverse resistance shows a linear field dependence,
the magnetoresistance follow a quadratic field dependence and obeys to Kohler's
rule. In contrast, Kohler's rule is strongly violated for samples having an
orthorhombic low temperature structure. However, the transport properties of
the orthorhombic samples can be satisfactory described by the three band model
with the pair of almost equivalent to the tetragonal sample hole and electron
bands, supplemented with the highly mobile electron band which has two order
smaller carrier number. Therefore, the peculiarity of the low temperature
transport properties of the orthorhombic Fe(SeS) samples, as probably of many
other orthorhombic iron superconductors, is due to the presence of a small
number of highly mobile carriers which originate from the local regions of the
Fermi surface, presumably, nearby the Van Hove singularity points
Self-oscillations in rocks,results of laboratory experiments
The method of generation of self-oscillations in rocks is developed here. Self-oscillations arise as a result of direct and inverse mechanoelectric transformations without an external generator. Laboratory experiments were
executed with different samples. A relation between self-oscillation parameters from samples humidity and direct electrical field applied to samples was detected
Magnetotransport properties of FeSe in fields up to 50T
Magnetotransport properties of the high-quality FeSe crystal, measured in a
wide temperature range and in magnetic fields up to 50 T, show the symmetry of
the main holelike and electronlike bands in this compound. In addition to the
main two bands, there is also a tiny, highly mobile, electronlike band which is
responsible for the non-linear behavior of (B) at low temperatures
and some other peculiarities of FeSe. We observe the inversion of the
temperature coeficient at a magnetic field higher than about 20 T
which is an implicit conformation of the electron-hole symmetry in the main
bands.Comment: MISM 201
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