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The NUCLEON space observatory is a direct cosmic ray spectrometer designed to study cosmic ray nuclei with $Z=1-30$ at energies $10^{12}-10^{15}$ eV. It was launched as an additional payload onboard the Russian Resource-P No. 2 satellite. In this work B/C, N/O and subFe/Fe ratios are presented. The experiment has worked for half of its expected time, so the data have preliminary status, but they already give clear indications of several astrophysical phenomena, which are briefly discussed in this paper.

The NUCLEON experiment is designed to measure chemical composition of cosmic rays with charges from Z=1 to 30 in an energy region from 5*10^11 to 10^15 eV. In this article the data analysis algorithm and spectra of Ni and Fe nuclei, measured in the NUCLEON experiment, are presented.

Data from the NUCLEON space observatory give a strong indication of the existence of a new universal cosmic ray "knee", which is observed in all groups of nuclei, including heavy nuclei, near a magnetic rigidity of about 10\,TV. Universality means the same position of the knee in the magnetic rigidity scale for all groups of nuclei. The knee is observed by both methods of measurement of particles energy implemented in the NUCLEON observatory---the calorimetric method and the kinematic method KLEM. This new cosmic ray "knee" is probably connected with the limit of acceleration of cosmic rays by some generic or nearby source of cosmic rays., Comment: 12 pages, 4 figures, 4 pages of Supplemental material (pictures). References improved

The results of experimental studies of the low-energy isomeric state in the $^{229}$Th nucleus are presented. The work is consisted of several stages. During the first stage $^{229}$Th nuclei were excited with the inverse internal conversion to the low-lying isomeric level in plasma that was formed by laser pulse at the $^{229}$Th-containing target surface. Then thorium ions having excited nuclei were extracted from the plasma by an external electrical field and implanted into thin SiO$_2$ film grown on a silicon substrate (that is a dielectric material with about 9 eV band-gap). Gamma decay of isomeric nuclei was registered during the second stage by the general methods of the electron spectroscopy after the photon-electron emission from the silicon substrate. Substitution of the photon registration with the electron one allowed us to increase the desired signal by several orders of magnitude and detect the $^{229}$Th nuclei decay. During the third stage the electron spectra from standard Xe VUV source was obtained that allowed determining the energy of photons. In order to prove that the detected signal is caused by isomeric $^{229}$Th nuclei decay a series of experiments was carried. The analysis of electron spectra gives the following results: the energy of the nuclear transition is $E_{\text{is}}=7.1(^{+0.1}_{-0.2})$~eV, the half-life of the isomeric level in bare nucleus in vacuum is $T_{1/2}=1880\pm170$~s, the reduced probability of the isomeric nuclear transition is $B_{\text{W.u.}}(M1;3/2^+\rightarrow 5/2^+)=(3.3\pm0.3)\times10^{-2}$., Comment: 11 pages, 11 figures

The NUCLEON experiment was designed to study the chemical composition and energy spectra of galactic cosmic ray nuclei from protons to zinc at energies of $\sim10^{11}$--$10^{15}$\,eV per particle. The research was carried out with the NUCLEON scientific equipment installed on the Russian satellite "Resurs-P" No.\,2 as an additional payload. This article presents the results for the measured nuclei spectra related to the first approximately 250 days of the scientific data collection during 2015 and 2016. The all-particle spectrum and the spectra of p, He, C, O, Ne, Mg, Si and Fe are presented. Some interesting ratios of the spectra are also presented and discussed. The experiment is now in its beginning stage and the data still have a preliminary character, but they already give numerous indications of the existence of various non-canonical phenomena in the physics of cosmic rays, which are expressed in the violation of a simple universal power law of the energy spectra. These features of the the data are briefly discussed., Comment: 14 pages, 16 figures, preprint for JCAP. V2 mathces the published version of the paper

The physical model describing the influence of the electronic subsystem on the properties of one-dimensional chains of metal is presented. It is shown that depending on an interaction potential between atoms in one-dimensional system formation of chains of various length is possible. In case the characteristic depth of the potential well of the interatomic interaction does not exceed a certain magnitude, the chains in 1D system are formed with length of several angstroms, while the increase the depth of the well also leads to the possibility of formation of metal chains of greater length., Comment: 12 pages, in Russian

The dependency of the melting point of supported metal nanoclusters as function of clusters height is theoretically investigated in the framework of the uniform approach. The vacancy mechanism describing the melting point shift in nanoclusters with decrease of their size is proposed. It is shown that the essential role in clusters melting point shift is played by van der Waals forces of cluster-substrate interaction. It is shown, that the account of layer--by--layer fusion of a cluster allows to satisfactorily describe the melting of nanoclusters of various metals, deposited onto a different substrates. The proposed model satisfactorily accounts for the experimental data.

The dependencies of the melting point and the lattice parameter of supported metal nanoclusters as functions of clusters height are theoretically investigated in the framework of the uniform approach. The vacancy mechanism describing the melting point and the lattice parameter shifts in nanoclusters with decrease of their size is proposed. It is shown that under the high vacuum conditions (p<10^-7 torr) the essential role in clusters melting point and lattice parameter shifts is played by the van der Waals forces of cluster-substrate interation. The proposed model satisfactorily accounts for the experimental data., Comment: 6 pages, 3 figures, 1 table