Abstract
A new method for two-stage laser enrichment of carbon-13 (
13
C) by isotope-selective IR multiphoton dissociation of Freon molecules is considered, which makes it possible to achieve a ...concentration of
13
C up to 99 % or higher with high productivity. At the first stage, as a result of the selective dissociation of CF
2
HCl (Freon-22) molecules, it is expected to obtain a C
2
F
4
dissociation product enriched in
13
C up to 30 % – 50 %. At the second stage, CF
2
Br
2
(Freon-12B2) is proposed to be used as a working substance, which is synthesised from enriched C
2
F
4
, and the enrichment process is carried out by selective deep ‘burning-out’ of the
12
C-containing component. Experiments on multiphoton dissociation of Freon-12B2 with an initial
13
CF
2
Br
2
concentration of 30 % in a mixture with oxygen by pulsed CO
2
laser radiation are performed. It is shown that reaching a
13
CF
2
Br
2
concentration of no lower than 99 % is possible at high values of the elementary separation act parameters: 15 % – 18 % dissociation yield and 40 – 75 selectivity for
12
CF
2
Br
2
molecules.
Collisional radiative involvement of molecules not absorbing IR laser radiation into resonance with a laser field has been investigated for the case when nonabsorbing and absorbing molecules are ...laser-irradiated in a two-component medium. Experiments have been conducted with a CF
2
HCl/CF
3
Br mixture at a 1/1 pressure ratio. Molecules have been excited by a pulsed CO
2
laser. Two types of experiments have been considered: (i) molecules were irradiated under nonequilibrium thermodynamic conditions due to a compression shock wave arising before the solid surface when it was subjected to a supersonic pulsed gasdynamically cooled molecular flux and (ii) molecules were irradiated under static conditions with a gas in the cell kept at room temperature. It has been found that when molecules vibrationally cooled in the compression shock wave (in this case, their IR absorption bands are narrow; the FWHM is 7–8 cm
–1
) are irradiated, initially nonabsorbing CF
2
HCl molecules get effectively involved into resonance with the laser field. Their effective dissociation (with dissociation yield β ≥ 10–15%) has been discovered when the CF
2
HCl/CF
3
Br mixture was irradiated under the condition of CO
2
laser frequency detuning by more than 15–25 cm
–1
from the center of the IR absorption band of molecules vibrationally cooled in the compression shock wave. If molecules are irradiated at room temperature (the gas temperature in the cell), in which case the IR absorption band of molecules is rather wide (25–30 cm
–1
), the collisional radiative involvement of CF
2
HCl molecules into interaction with the laser field, albeit less pronounced, persists.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In order to determine the specifics of subordination, reordination and coordination ties in the structure of other measures of a criminal-legal nature, the content of the system of these measures is ...analysed, in which it is proposed to include measures related to isolation or restriction of personal freedom and measures related to the restriction of property rights. It is suggested to define a system of other measures of a criminal-legal nature as a holistic set, built on a hierarchical principle and divided into two subsystems, the normative reflection of which takes place in the provisions of the General Part of the Criminal Code of the Russian Federation, and social — in specific public relations arising from the commission of a crime and the need to apply criminal law measures to it. In the study of external subordinate relations, it is concluded that other measures of a criminal-legal nature have become a full-fledged component of criminal law, alternative to criminal punishment or supplementing the restrictions on the rights and freedoms of the convicted person arising from the application of punishment. Internal subordinate ties reflect the structure of the system of other measures of a criminal-legal nature and allows them to be distributed according to their functional purpose. The conclusion is made that the reordination ties demonstrate the cosubordination of the subsystem of the system for other measures of a criminal-legal nature, as well as a blanket (reference) interaction with other elements of the system of criminal-legal action, or with other spheres of social life, which intersect with negative social phenomena. Also, it is substantiated that coordination ties in the structure of the system of other measures of a criminal-legal nature are unilateral and create conditions for the use of discretionary powers related to the preservation of the application of these measures or refusal of them in favor of a stricter criminal-legal act, punishment.
The discovery of topological order has revised the understanding of quantum matter and provided the theoretical foundation for many quantum error–correcting codes. Realizing topologically ordered ...states has proven to be challenging in both condensed matter and synthetic quantum systems. We prepared the ground state of the toric code Hamiltonian using an efficient quantum circuit on a superconducting quantum processor. We measured a topological entanglement entropy near the expected value of –ln2 and simulated anyon interferometry to extract the braiding statistics of the emergent excitations. Furthermore, we investigated key aspects of the surface code, including logical state injection and the decay of the nonlocal order parameter. Our results demonstrate the potential for quantum processors to provide insights into topological quantum matter and quantum error correction.
Refrigerants and environment Tsvetkov, O B; Laptev, Yu A
Journal of physics. Conference series,
11/2017, Volume:
891, Issue:
1
Journal Article
Peer reviewed
Open access
The refrigeration and air-conditioning industries are important sectors of the economy and represents about 15 % of global electricity consumptions. The chlorofluorocarbons also called CFCs are a ...class of refrigerants containing the halogens chlorine and/or fluorine on a carbon skeleton. Because of their environmental impact the Montreal Protocol was negotiated in 1987 to limit the production of certain CFCs and hydrochlirofluorocarbons (HCFCs) in developed and developing countries. The halogenated refrigerants are depleting the ozone layer also major contribution to the greenhouse effect. To be acceptable as a refrigerant a fluid must satisfy a variety of thermodynamic criteria and should be environment friendly with zero Ozone Depletion Potential and low Global Warming Potential. The perspective of a future phase down of HFCs is considered in this report taking into account a strategy for the phase out of HCFCs and perspective of choosing of various refrigerant followed by safety issues.
A variant of a two-stage laser process for production highly enriched carbon-13 (13C) with a concentration of more than 99% is being investigated. The first laser stage provides effective enrichment ...of 13C up to 30-50% based on the isotopically selective multiphoton dissociation of freon-22 (CF2HCl) by pulsed radiation of a CO2 laser. Then the product of the first stage tetrafluoroethylene, enriched in 13C, is converted into the working substance of the second stage, freon-12B2 (CF2Br2). At the second stage of enrichment, a component with an undesirable isotope 12C undergoes to selective dissociation, until its concentration in the residual gas decreases to 1% and the concentration of the 13C isotope is increased to 99%. In preliminary experiments, high parameters of the elementary act of separation were achieved - the dissociation yield of the 12CF2Br2 up to 20% and selectivity (for 12C) up to 100. A productivity of the second enrichment stage for a reactor of ideal displacement is estimated, that is 0.6 and 1.2 g13C/h for initial concentrations of 13CF2Br2 30 and 50%, respectively.
The ionization chamber component of the SPIDER detector has been designed to measure energy loss and kinetic energy of fragments produced through neutron-induced fission with energy resolutions of ...<1% and a time-dependent signal collection. Important design elements implemented are an axial configuration of the electrodes for improved energy loss and measurement and a thin silicon nitride entrance window to minimize both energy loss and energy straggling of the incoming fragments. High energy resolution and improved charge resolution from the ionization chamber are combined with the high precision of the upstream time-of-flight component of SPIDER to achieve resolutions in mass and nuclear charge of 1 AMU and Z=1. A discussion of the present resolution capabilities of the ionization chamber will be presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
During the primary treatment of oil, gas and water, complications arise associated with the presence of hard water-oil emulsions, which cause an increase in fluid pressure in the gathering systems, ...pipeline damage, as well as difficulties in gas separation and preliminary water discharge at the preliminary discharge unit (PRU). Additional problems arise during transportation of highly paraffinic oils associated with the crystallization of paraffin in the flow path of the oilfield equipment and on the inner surface of pipes, leading to a drop in the productivity of pipelines.
Article discusses the technology of magnetic-reagent treatment of water-oil media, which allows intensifying the processes of primary oil treatment at the facilities of its production. Bench and pilot tests have shown the ability of the magnetic field to accelerate oil demulsification processes, increasing the percentage of separated water during subsequent settling, and to reduce asphalt-resin-paraffin deposits (ARPD) on the inner surface of oil and gas field equipment.
Mechanism of the magnetic field effect on water-oil media is described. Effect of treatment on the integrity of the armour shells of oil-water emulsions was studied. Various modes of magnetic treatment have been investigated with evaluation of its effectiveness. It is shown that the best effect is achieved with the combined use of reagents and a magnetic field. Synergistic effect is observed, which consists in increasing their effectiveness. This made it possible to conclude that this method can be applied to reduce the consumption of reagents used in oil production while maintaining the treatment efficiency.
The SPectrometer for Ion DEtermination in fission Research (SPIDER) measures both position and time-of-flight (TOF) of charged particles using a system of thin carbon foils, electrostatic mirrors, ...microchannel plates, delay-line anodes, and a fast TDC. Tests have been conducted using 229Th and the alpha emitters in its decay chain. To date, timing resolution of 200 ps (FWHM) has been achieved corresponding to roughly 0.5% uncertainty in velocity measurements of fission fragments over a flight path of 52.1 cm. This velocity resolution, in combination with demonstrated fragment energy resolution is sufficient for 1 amu resolution of light mass fragments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The absolute total cross sections for np and pp scattering below 1000 MeV are determined based on partial-wave analyses (PWAs) of nucleon-nucleon scattering data. These cross sections are compared ...with the most recent ENDF/B-VII.0 and JENDL-3.3 data files, and the Nijmegen PWA. Systematic deviations from the ENDF/B-VII.0 and JENDL-3.3 evaluations are found to exist in the low-energy region. Comparison of the np evaluation with the result of most recent np total and differential cross section measurements will be discussed. Results of those measurements were not used in the evaluation database. A comparison was done to check a quality of evaluation and its capabilities to predict experimental observables. Excellent agreement was found between the new experimental data and our PWA predictions. KCI Citation Count: 1
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