It was found that tetrakis(hydroxymethyl)glycoluril is unstable in aqueous solutions and undergoes stepwise dehydroxymethylation. The products of this process were identified by HPLC, 1D and 2D NMR ...spectroscopy. The main product of hydrolytic degradation at room temperature is tris(hydroxymethyl)glycoluril, which may be conditioned by the thermodynamic characteristics of the reaction. Further dehydroxymethylation to give di- and monohydroxymethyl glycoluril derivatives occurs under more severe conditions.
The work addresses the manufacturing of capillary tubes, involving drawing on a long movable mandrel and their subsequent reeling along the outer diameter in order to extract the mandrel, resulting ...in finished tubes of the desired quality. The two-stage finite element modeling (FEM) included varying key parameters such as tube reduction and clearance between the tube and the mandrel over a wide range. At the first stage, the permissible reduction was determined with a limit on the tolerance for the outer diameter. At the second stage, the occurrence of tube faceting was studied.
In the decommissioning of the campus B at VNIINM located in a dense residential area in Moscow special attention was devoted to radiation monitoring. For this, the automated radiation monitoring ...system (ARMS) and mobile-ARMS were involved, the former during decommissioning and the latter during the most critical work; additional measurements were performed in the ventilation channel over 168 days. ARMS in the automatic mode performed 112,492,800 measurements of the γ-exposure dose rate and 793,152 measurements of the concentration of aerosols containing α- and β-emitting radionuclides; the mobile system performed 17,038,080 and 84,796 measurements, respectively. Radiation monitoring was conducted in the man-made objects at VNIINM and on components of the environment on and off the grounds of the enterprise.
Rehabilitation of Building 53 at VNIINM Kuznetsov, A. Yu; Antsiferova, E. Yu; Belousov, S. V. ...
Atomic energy (New York, N.Y.),
07/2019, Letnik:
126, Številka:
3
Journal Article
Recenzirano
A complex of decontamination and dismantling work on removing radiation contaminated equipment and special utility lines in the previously mothballed building 53 at VNIINM has been implemented. The ...33.1 m long air pathway between building 53 and building B, contaminated by α-emitters to 120 particles/(cm
2
·min), has been dismantled. Thirty-three pieces of large-size equipment were dismantled. Fifteen pieces of equipment were decontaminated. Special utility lines of the building were completely dismantled: ~140 m special drain lines and ~320 m special ventilation. Approximately 180 m of piping has been decontaminated. Low-waste decontamination procedures made it possible to reduce the amount of radwaste produced during rehabilitation work by more than 1.5 times (to 27 m
3
). A radiation survey established that the procedure has unlimited application in the enterprise’s business activities taking into consideration the location on the industrial site at VNIINM.
The application of degassed oil instead of recombined oil model for a slim tube technique was investigated. It is found that the use of degassed oil is not recommended for modeling and studying of ...gas and oil miscibility under typical conditions of Western Siberia deposits. The previously estimated miscibility of light oil and associated gas was confirmed in case of application of recombined oil model or degassed oil at displacement from a slim tube. This occurs because of a gradual transition from the mode of immiscible displacement to the mode of limited-mixing displacement of oil and further to the mode of complete mixing as a result of the mass exchange of light oil and associated gas.
The differential cross sections for the
12
C(
3
He,
t
)
12
N reaction leading to formation of the 1
+
(ground state), 2
+
(0.96 MeV), 2
−
(1.19 MeV), and 1
−
(1.80 MeV) states of
12
N are measured at
...E
(
3
He) = 40 MeV. The analysis of the data is carried out within the modified diffraction model and distorted wave Born approximation. Increased rms radii have been obtained for the ground, 2
−
(1.19 MeV), and 1
−
(1.80 MeV) states. We revealed that
12
B,
12
N, and
12
C in the isobaric analogue states with
T
= 1, and spin-parities 2
−
and 1
−
have increased radii and exhibit properties of neutron and proton halo states.
A range of preparatory tasks for decommissioning the U-5 facility at VNIINM was performed in 2010–2016. Comprehensive engineering and radiation inspections were conducted, and cartograms of ...contamination were constructed. Deposits in the special utility systems were investigated. A detailed investigation of the contamination of the building structures was performed. Radioactively contaminated process media, sources of ionizing radiation, and radioactive wastes from technological equipment and rooms were removed. Design documentation for decommissioning the U-5 facility was developed and a positive final report by a government environmental commission of experts, final sanitary-epidemiological reports, and licensing for decommissioning were obtained. The measures made it possible to increase the radiation safety of the facility and prepare it for decommissioning.
Use of a combination of multistage hydrofracking and high-pressure air injection is proposed for developing low-permeability oil deposits of the Tyumen Suite (Upper Jurassic). An effective inert ...gaseous agent is formed during intrastratal transformation of the air due to oxidation of the oil. The oil autooxidation mechanism is studied. A weak dependence of the oxidation rate on the oil properties is observed.
Two independent methods: Asymptotic Normalization Coefficients (ANC) and Modified Diffraction Model (MDM) were applied to new and existing experimental data to search for states with enhanced radii ...in isobaric analogue states (IAS) of 12B and 12N. The ANC analysis of the 11B(d,p)12B reaction at Ed = 21.5 MeV has confirmed neutron halo existence for two states of 12B: 2−, 1.67 MeV and 1−, 2.62 MeV 1. Some new results were obtained for higher excited states: halo-like states were observed for 0+, 2.72 MeV and 3−, 3.39 MeV states. It should be mentioned that the last one is unbound state, which is 19 keV above the neutron emission threshold and in both states last neutron has a non-zero orbital momentum (ln=1 and ln=2 correspondingly). We propose to use MDM to study isobaric analogue states of 12B in the mirror 12N nucleus and apply it to analyze the (3He,t) reaction data. The existing in the literature data are not completed enough to make definite conclusion about halo in the 2− and 1− states of 12N. This fact simulated us to carry out a new experiment on the 12C(3He,t)12N reaction at the end of 2018. The measurements were conducted at the University of Jyväskylä (Finland) using the K130 cyclotron to produce a 3He beam at E(3He)=40 MeV. The differential cross sections of the 12C(3He,t)12N reaction were measured in the c.m. angular range 8°-70°. Preliminary results for angular distributions are obtained. MDM analysis of preliminary (3He,t) experimental data is done.
PDF
