48 research outputs found
Fukushima plutonium effect and blow-up regimes in neutron-multiplying media
It is shown that the capture and fission cross-sections of 238U and 239Pu
increase with temperature within 1000-3000 K range, in contrast to those of
235U, that under certain conditions may lead to the so-called blow-up modes,
stimulating the anomalous neutron flux and nuclear fuel temperature growth.
Some features of the blow-up regimes in neutron-multiplying media are
discussed.Comment: 15 pages, 8 figures. (v2: numerous corrections and style
improvements). arXiv admin note: substantial text overlap with
arXiv:1207.369
ІНСТРУМЕНТАЛЬНІ ОСНОВИ НАНОЕКОЛОГІЇ
Nanomaterials transfer into the environment is a new environmental hazard that must be investigated and the corresponding instrumental apparatus for its control must be created. The existing traditional devices of nanomaterials investigation despite their bulkiness enables preforming laboratory investigations of nanoparticles ecological impact depending on their characteristics. However new portable devices are required for ecological services. Corresponding training is also needed. For any nanoparticles ecological safety estimate an universal algorithm should be developed for estimate of potential environmental hazard level depending on characteristics of the specific nanomaterials.Попадание наноматериалов в окружающую среду - новая экологическая опасность, которую необходимо исследовать и создать инструментальные средства для ее контроля. Существующие традиционные приборы исследования наноматериалов, несмотря на их громоздкость, позволяют проведение лабораторного исследования экологического воздействия наночастиц в зависимости от их характеристик. Однако для экологических служб необходимы новые портативные инструментальные средства и соответствующая теоретическая подготовка. Для оценки экологической безопасности любых наночастиц необходимо разработать универсальный алгоритм оценки уровня потенциальной экологической опасности в зависимости от характеристик конкретных подконтрольных наноматериалов.Потрапляння наноматеріалів у навколишнє середовище – нова екологічна небезпека, яку необхідно досліджувати і мати інструментальні засоби для її контролю. Існуючі традиційні прилади дослідження наноматеріалів, незважаючи на їх громіздкість, дозволяють проведення лабораторного дослідження екологічного впливу наночастинок залежно від їх характеристик. Однак для екологічних служб необхідні нові портативні інструментальні засоби та відповідна теоретична підготовка. Для оцінки екологічної безпеки будь-яких наночастинок необхідно розробити універсальний алгоритм оцінки рівня потенційної екологічної небезпеки залежно від характеристик конкретних підконтрольних наноматеріалів
Mechanism of Deep-focus Earthquakes Anomalous Statistics
Analyzing the NEIC-data we have shown that the spatial deep-focus earthquake
distribution in the Earth interior over the 1993-2006 is characterized by the
clearly defined periodical fine discrete structure with period L=50 km, which
is solely generated by earthquakes with magnitude M 3.9 to 5.3 and only on the
convergent boundary of plates. To describe the formation of this structure we
used the model of complex systems by A. Volynskii and S. Bazhenov. The key
property of this model consists in the presence of a rigid coating on a soft
substratum. It is shown that in subduction processes the role of a rigid
coating plays the slab substance (lithosphere) and the upper mantle acts as a
soft substratum. Within the framework of this model we have obtained the
estimation of average values of stress in the upper mantle and Young's modulus
for the oceanic slab (lithosphere) and upper mantle.Comment: 9 pages, 7 figure
On some fundamental peculiarities of the traveling wave reactor
On the basis of the condition for nuclear burning wave existence in the
neutron-multiplicating media (U-Pu and Th-U cycles) we show the possibility of
surmounting the so-called dpa-parameter problem, and suggest an algorithm of
the optimal nuclear burning wave mode adjustment, which is supposed to yield
the wave parameters (fluence/neutron flux, width and speed of nuclear burning
wave) that satisfy the dpa-condition associated with the tolerable level of the
reactor materials radioactive stability, in particular that of the cladding
materials.
It is shown for the first time that the capture and fission cross-sections of
U and Pu increase with temperature within 1000-3000K range,
which under certain conditions may lead to a global loss of the nuclear burning
wave stability. Some variants of the possible stability loss due to the
so-called blow-up modes (anomalous nuclear fuel temperature and neutron flow
evolution) are discussed and are found to possibly become a reason for a
trivial violation of the traveling wave reactor internal safety.Comment: 44 pages, 19 figures, 2 table
Damage to extreme-ultraviolet Sc/Si multilayer mirrors exposed to intense 46.9-nm laser pulses
Includes bibliographical references (page 622).The damage threshold and damage mechanism of extreme-ultraviolet Sc/Si multilayer mirror coatings are investigated with focused nanosecond pulses at 46.9-nm radiation from a compact capillary-discharge laser. Damage threshold fluences of ~0.08 J/cm2 are measured for coatings deposited on both borosilicate glass and Si substrates. The use of scanning and transmission electron microscopy and small-angle x-ray diffraction techniques reveals the thermal nature of the damage mechanism. The results are relevant to the use of newly developed high-flux extreme-ultraviolet sources in applications
KamLAND-experiment and Soliton-like Nuclear Georeactor. Part 1. Comparison of Theory with Experiment
We give an alternative description of the data produced in the KamLAND
experiment, assuming the existence of a natural nuclear reactor on the boundary
of the liquid and solid phases of the Earth's core. Analyzing the uncertainty
of antineutrino spectrum of georeactor origin, we show that the theoretical
(which takes into account the soliton-like nuclear georeactor) total reactor
antineutrino spectra describe with good accuracy the experimental KamLAND-data
over the years of 2002-2007 and 2002-2009, respectively. At the same time the
parameters of mixing ({\Delta}(m21)^2=2.5\cdot 10^-5 eV^2,
tan^2{\theta}12=0.437) calculated within the framework of georeactor hypothesis
substantially differ from the parameters of mixing ({\Delta}(m21)^2=7.49\cdot
10^-5 eV^2, tan^2{\theta}12=0.436) obtained in KamLAND-experiment for total
exposure over the period of 2002-2009. By traingulation of KamLAND and Borexino
data we have constructed the coordinate location of soliton-like nuclear
georeactors on the boundary of the liquid and solid phases of the Earth core.
Based on the necessary condition of full synchronization of geological
(magnetic) time scale and time evolution of heat power of nuclear georeactor,
which plays the role of energy source of the Earth magnetic field, and also the
strong negative correlation between magnetic field of the solar tachocline zone
and magnetic field of the Earth liquid core (Y-component) we have obtain the
estimation of nuclear georeactor average heat power ~30 TW over the years
2002-2009.Comment: 50 pages; 17 figures; 1 table. A substantially revised, corrected and
enhanced editio
The peculiarities of cross-correlation between two secondary precursors - radon and magnetic field variations, induced by stress transfer changes
A model of precursor manifestation mechanisms, stimulated by tectonic
activity and some peculiarities of observer strategy, whose main task is the
effective measurement of precursors in the spatial area of their occurrence on
the Earth's daylight, are considered. In particular, the applicability of
Dobrovolsky's approximation is analyzed, when an unperturbed medium
(characterized by the simple shear state) and the area of tectonic activity
(local inhomogeneity caused by the change only of shear modulus) are linearly
elastic, and perturbation, in particular, surface displacement is calculated as
a difference of the solutions of two independent static problems of the theory
of elasticity with the same boundary condition on the surface. Within the
framework of this approximation a formula for the spatial distribution (of
first component) of magnetic field variations caused by piezomagnetic effect in
the case of perturbed regular medium, which is in simple shear state is
derived. Cogent arguments in favor of linear dependence between the radon
spatial distribution and conditional deformation are obtained.
Changes in magnetic field strength and radon concentrations were measured
along a tectonomagnetic profile of the total length of 11 km in the
surroundings of the "Academician Vernadsky" Station on the Antarctic Peninsula
(W 64{\deg}16', S 65{\deg}15'). Results showed a positive correlation between
the annual surface radon concentration and annual changes of magnetic field
relative to a base point, and also the good coincidence with theoretical
calculation.Comment: 27 pages, 11 figures, 3 tables (a substantially revised and extended
edition; v3 -- some analysis of recent publications added
Nanoimaging with a compact extreme-ultraviolet laser
Includes bibliographical references (page 2097).Images with a spatial resolution of 120-150 nm were obtained with 46.9 nm light from a compact capillary-discharge laser by use of the combination of a Sc-Si multilayer-coated Schwarzschild condenser and a freestanding imaging zone plate. The results are relevant to the development of compact extreme-ultraviolet laser-based imaging tools for nanoscience and nanotechnology