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The article is devoted to study of the D(3He, p)4He reaction in the 3He+ ion energy range EHe = 16÷34 keV (E= 6.41÷13.61 keV in the center-of-mass system) with a step of 2 keV. The goal of this paper was to determine experimentally the electron screening potential U e and the enhancement factor of the D(3He, p)4He reaction using the deuterated metal targets ZrD with different crystal textures. In this work we present results of measuring the D(3He, p)4He reaction enhancement factor using the targets ZrD with Miller indices [111] and [100]. The ZrD targets was deposited on the stainless steel foil 50 μm thick. The protons of energy 14.7 MeV from the D(3He, p)4He reaction were detected by a scintillation detector based on the BC-404 scintillator 115 mm in diameter and 4 mm thick, which was placed in optical contact with the XP-2040 PMT. The measured enhancement factors of the D(3He, p)4He reaction much higher than for gas targets and energy behavior is not described by the classical exponential formula. The effect of the crystal structure of the targets is evident. The measured enhancement factors of the D(3He, p)4He reaction are higher for the ZrD target with a crystal structure characterized by the Miller index [100] than for the target with index [111], which probably indicates the contribution of channeling. A non-proportional increase of the enhancement factors for the D(3He, p)4He reaction in energy range 16÷22 keV probably indicates a low-lying resonance effect in 5Li.

Perylene derivatives with chlorine atoms attached at the bay position to the dye core are expected to affect organisation and tendency to aggregation in Langmuir and Langmuir–Blodgett (LB) films. Therefore, newly synthesized core–twisted homologous series of tetrachloroperylene tetracarboxylic acid esters with n = 1,4,5,6,9 carbon atoms in terminal alkyl chains were studied. Phase transitions and crystalline structures were specified by differential scanning calorimetry (DSC) and single crystal X–ray diffraction (XRD), respectively. Intermolecular interactions and organisation of the dyes in monomolecular films were investigated by means of Brewster angle microscope (BAM), UV–Vis absorption and emission spectroscopy, fluorescence microscopy and atomic force microscopy (AFM). The dyes investigated do not form thermotropic mesogenic phases in bulk. The crystalline triclinic elementary cell with P–1 symmetry is revealed from X–ray experiments. In Langmuir and Langmuir–Blodgett films molecular tilted head–on alignment is postulated. Spectroscopic research confirmed by AFM texture images of the LB films show that in the Langmuir and LB films the dyes, depending on length of terminal chains, have a tendency to create H or I molecular aggregates. The impact of the twisted core on the molecular behavior in a bulk and thin films is discussed.

The cosmological lithium problem, that is, a noticeable discrepancy between the predicted and observed abundances of lithium, is in conflict with the Standard Big Bang Nucleosynthesis model. For example, the abundance of 7Li is 2–4 times smaller than predicted by the Standard Big Bang Nucleosynthesis. As to the abundance of 6Li, recent more accurate optical investigations have yielded only the upper limit on the 6Li/7Li ratio, which makes the problem of 6Li abundance and accordingly of disagreement with the Standard Big Bang Nucleosynthesis predictions less acute. However, experimental study of the D(4He, γ)6Li reaction cross section is still of current importance because there is a theoretical approach predicting its anomalously large value in the region of energies below the Standard Big Bang Nucleosynthesis energy. The work is dedicated to the measurement of the cross section for the D(4He, γ)6Li reaction proceeding in zirconium deuteride at the incident 4He+ion energy of 36 keV. The experiment is performed at a pulsed Hall plasma accelerator with an energy spread of 20% FWHM. A method for direct measurement of the background from the reaction chain D(4He, 4He)D→D(D, n)3He→(n, γ) and/or (n, n′γ) ending with activation of the surrounding material by neutrons is proposed and implemented in the work. An upper limit on the D(4He, γ)6Li reaction cross section σ≤7·10−36 cm2 at the 90% confidence level is obtained.

Methods for depositing thin layers of deuterides TiD 2 , ZrD 2 , NbD, and CrD 2 on stainless steel substrates are described. Magnetron sputtering of nanolayers of the above deuterides with different textures is considered. A technology for making titanium, zirconium, niobium, and chromium deuteride targets is proposed, which will definitely verify the hypothesis of the enhancement of the dd and pd reactions due to the channeling of the deuterons in the crystals of the above deuterides.

Energy dependence of the neutron yield from the d ( d , n ) 3 He reaction in a textured target of titanium deuteride with predominant [1 0 0] orientation of microcrystals is investigated. The measurements were performed for the incident deuteron energies ranging from 7 to 12 keV in the laboratory coordinate system. It is shown that the energy dependence of the enhancement factor is described not only by the screening potential but also by simply taking account of channeling effects.

The article is devoted to the investigation of a pd -reaction ( p + d → 3 He+ γ (5.5 MeV)) undergoing in titanium deuteride in astrophysical collision energy region of protons and deuterons ranging from 5.3 to 10.5 keV. The experiments have been performed using the Hall NSR TPU (Tomsk, Russia) pulsed plasma accelerator. The number of accelerated protons in 10 μs pulse was 5×10 14 at a repetition rate of 7×10 −2 Hz. Detection of 5.5 MeV gamma rays was carried out using eight detectors based on crystals of NaI(Tl) (100×100×400 mm) placed around the TiD target. For the first time, the dependencies between the astrophysical S -factor and the effective cross-section of the pd -reaction from proton to deuteron collision energy, and the potential electronic screening of the interacting protons and deuterons in titanium deuteride have been measured.

The present paper is devoted to the study of the electron screening effect influence on the rate of d ( d , n ) He 3 reaction in the ultralow deuteron collision energy range in the deuterated metals (ZrD 2 , TiD 2 and TaD 0.5 ). The ZrD 2 , TiD 2 and TaD0.5 targets were fabricated via magnetron sputtering of titanium, zirconium and tantalum in gas (deuterium) environment. The experiments have been carried out using the high-current pulsed Hall plasma accelerator (NSR TPU, Russia). The detection of neutrons with energy of 2.5 MeV from the dd reaction was done with plastic scintillation spectrometers. As a result of the experiments, the energy dependences of the astrophysical S -factor for the dd reaction in the deuteron collision energy range of 2–7 keV and the values of the electron screening potential U e of the interacting deuterons have been measured for the above targets: U e ( ZrD 2 ) = ( 205 ± 35 ) eV ; U e ( TiD 2 ) = ( 125 ± 34 ) eV ; U e ( TaD 0.5 ) = ( 313 ± 58 ) eV . Our results are compared with the other published experimental and calculated data.

The pd reaction at ultra-low proton–deuteron collision energies has been studied using the Hall pulsed ion accelerator and the solid target of heavy water D2O. The experiment on measurement of the astrophysical S pd factor and the pd reaction cross-section was carried out at average pd collision energies 8.28, 9.49, and 10.10 keV. The 5.5-MeV γ rays from the pd reaction were detected by detectors based on plastic scintillators and NaI(Tl) crystals. Parameters of the accelerated hydrogen ion flux were measured and monitored with diagnostic equipment consisting of an energy analyzer, plasma optical radiation detectors, the Rogovsky belt, and collimated Faraday cups. The results obtained agree within the errors with the data of the pd experiments carried out by the LUNA collaboration at the Gran Sasso Laboratory with a target filled with gaseous deuterium. The reported experiment was carried out at the Hall ion accelerator of the Research Institute of Nuclear Physics, Tomsk Polytechnic University.

A method for experimental determination of the nuclear fusion rates in the dμ He molecules in the states with J=0 and J=1 ( J is the orbital moment of the system) and of the effective rate of transition between these states (rotational transition 1–0) is proposed. It is shown that information on the desired characteristics can be found from joint analysis of the time distribution and yield of products of nuclear fusion reactions in deuterium–helium muonic molecules and muonic X-ray obtained in experiments with the D 2 +He mixture at three (and more) appreciably different densities. The planned experiments with the D 2 + He mixture at the meson facility PSI (Switzerland) are optimized to gain more accurate information about the desired parameters on the assumption that different mechanisms for the 1–0 transition of the dμ He complex are realized.

The outer membranes of mitochondria prepared from the liver of rats kept 12 days on a choline-deficient diet were analyzed for changes in phospholipid and protein content. The total amount of phospholipid in the outer membranes was not affected by the deficiency. There was, however, a significant decrease in the amount of phosphatidylcholine and an increase in phosphatidylethanolamine. The alterations in the membrane phospholipids were reflected in a reduction in the fluorescence of the membrane probe, 8-anilino-1-naphthalene sulfonate. Choline deficiency also affected the protein composition of the outer membranes as judged by electrophoretic analysis; however, the activity of several enzymes which serve as markers for the outer membrane was not affected by the deficiency.