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•Gas-phase conversion of waste PET in the nitrating atmosphere was studied.•Major component of solutions of PET conversion products (NPET) in NaOH is C8H4O4Na2.•Ozonating the ...solutions of NPET in NaOH destroys organic impurities by at least ∼85 %.•Mixing HNO3 or HCl with solutions of NPET in NaOH provides 100 % yield of TPA.
The paper describes a new method of waste polyethylene terephthalate (PET) recycling based on gas-phase treatment of the material in nitrating atmosphere. It was found that PET samples kept in the nitrating atmosphere (obtained by vaporizing 12 mol L−1 HNO3) at a temperature of 403–463 K (130–190 °C) for 5–24 h dissolve in 0.5 mol L−1 NaOH, in contrast to the untreated PET samples. Ozonation of the obtained alkaline solutions leads to a complete decomposition of the organic compounds present in the solutions. The resulting PET decomposition degree is higher than 99.9 % irrespective of the plastic color. In addition, the possibility of terephthalic acid recovery from the alkaline solutions of the conversion products was shown.
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The heat transfer between subsonic jets of dissociated air flowing from a slit nozzle and the surface of a flat plate at an angle of attack has been experimentally studied using a VGU-4 HF ...plasmatron. An effect of pressure in the plasmatron chamber exerted on the range of the air plasma jet, as well as an effect of the generator power on heat flux distribution throughout the surface of a copper plate at an angle of attack at a pressure in the test chamber amounting to 50 and 100 hPa have been studied. Heat fluxes are determined for the case of a low-catalytic surface of the heat-shielding tile of the
Buran
orbital spacecraft depending on the generator power, the pressure in the chamber, as well as the angle of attack. Heat exchange parameters inherent in the copper surface and those inherent in the low catalytic surface of a heat-shielding tile of the
Buran
orbital spacecraft have been compared for the case of the same flow mode.
Methods for Screening Live Cells Gordeev, A. A.; Chetverin, A. B.
Biochemistry (Moscow),
2018/1, Letnik:
83, Številka:
Suppl 1
Journal Article
Recenzirano
Cell screening or, in other words, identification of cells with certain properties is now increasingly used in scientific and medical research, e.g., in diagnostics, drug testing, and production of ...cell clones with desired characteristics. In this review, we discuss existing methods of cell screening and their classification according to the cell presentation format. We describe the principles of the one-dimensional and two-dimensional formats and compare the main advantages and drawbacks of these formats. The first part describes the methods based on the 2D-format of cell presentation, when cells are immobilized in the same plane by various techniques. The second part describes the methods of the 1D-screening, when cells are aligned in a line in a stream of fluid and scanned one-by-one while passing through a detector. The final part of the review describes the method of high-performance cell analysis based on the merged gel technique. This technique combines the advantages of both 1D and 2D formats and, according to the authors, might become an effective alternative to many modern methods of cell screening.
In this paper, we review the nomenclature and main technical requirements for radiation monitoring software and hardware for building stationary measuring channels used as a part of ...information-measuring systems at high-capacity NPPs of Russian design that are in operation or currently under construction. Operational and metrological characteristics of the equipment of automated radiation monitoring systems available in the market in comparison with the design requirements are compared. Generalizing conclusions are made about the prospects for the development of the direction of radiation monitoring with allowance for the further improvement of the equipment and experience in the creation and commissioning of APCSs for nuclear power plants during their construction and modernization.
Abstract
Experiments of our earlier work on the study of stimulated thermal scattering of the second harmonic of neodymium laser radiation in toluene are reproduced in order to confirm the put ...forward hypothesis about the nature of the laser beam structure decay in the focal plane of a short-focus lens. Experiments were carried out under similar conditions, but with a liquid (CCl
4
), in which there is no two-photon absorption of the second harmonic radiation from a neodymium laser. A conclusion is made that the spatial structure decay of the laser beam of the second harmonic of the Nd : YAG laser radiation focused by short-focus lenses with a numerical aperture NA ∼ 0.1 in toluene is associated with two-photon absorption.
Abstract
An equation is obtained to describe two-photon absorption of light beams of variable cross section. It is shown that the experimental values of the two-photon absorption coefficients of ...focused laser beams, calculated in the plane-wave approximation in the focal waist region and taking into account the variable cross section of the light beam, differ by two orders of magnitude.
The solubility of ozone in solutions of oxalic acid H
2
C
2
O
4
and potassium nitrate at concentrations up to 1 and 2 M, respectively, is studied at 25°C. The Sechenov constants for these electrolyte ...solutions are found: 0.081 ± 0.010 and 0.082 ± 0.004 M
–1
, respectively. The anion-specific parameter in the Weisenberger–Schumpe gas solubility model for oxalate ion is determined:
= 0.1266 M
–1
. A set of coefficients is determined using the experimental data from various sources to calculate the density of H
2
C
2
O
4
solutions as a function of temperature in the range of 5–100°C at solution concentrations up to the saturated concentration at a given temperature.
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