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At the present time, the Dubna gas-filled separator is the world's leading physical facility in the field of synthesis of superheavy elements. This is the device where new elements with Z = 114-118 (Fl, Mc, Lv, Ts, Og) were synthesized. The original tools and methods considered in this paper are applied in reactions of complete fusion of actinide target + 48Ca → SHN + xn type. Modification of the active correlation method is planned after the launch of new DC-280 cyclotron developed at the Flerov Laboratory of Nuclear Reactions in 2019. [ABSTRACT FROM AUTHOR]

In many innovative physical experiments such (as, e.g., the synthesis of superheavy elements) the statistics of the observed data is often small and there is not enough of the a priori information about the parameters of their distribution function. Here the first important problem is to get sure that the data is “pure”, i.e. the events are produced by one factor and not by several. Although the available methods for the problem solution are numerous, the most popular methods using the regressions or likelihood relations, for the above reason are not expedient for our case. The non-parametrical tests having the reputation of parameter-independent and little-sensitive to the data statistics, seem here to be the most suitable. The paper suggests such a non-parametrical criterion for purity of the exponential event distribution: the ratio of the sample median and the sample mean. Actually the method can be generalized to be used for some other distributions, first of all, the normal one. [ABSTRACT FROM AUTHOR]

Triple compounds with the formulas TlFeS2 and TlFeSe2 and magnetic properties are investigated via X-ray diffraction, differential-thermal, and thermogravimetric analyses. Their crystal structures are found. It is ascertained that they are described by monoclinic space group C2/m under normal conditions. The atomic coordinates and interatomic distances are determined. From differential-thermal and thermogravimetric analyses performed at temperatures of 30-900°C, it is revealed that stronger covalent bonds are implemented in TlFeS2 crystals than in TlFeSe2 compounds. The effects associated with energy exchange in the compounds under study are observed. The physical nature of the observed effects is discussed. [ABSTRACT FROM AUTHOR]

Neutron diffraction studies of a α → γ structural phase transition (Tc ≈ 911°C) in iron samples at different initial states have been performed. The anomalous disappearance of a diffraction pattern is observed in iron in the region of the α → γ phase transition. At repeated heating processes of an as cast sample, this effect becomes less pronounced and it is absent at the heating of iron powder. The observed effects have been assumingly attributed to the formation of small paracrystalline clusters with a large dispersion of the cell parameters in the process of phase transition. The kinetics of formation of clusters is slowed in as cast samples, which leads to the temporal disappearance of the diffraction pattern. These results make it possible to reconsider the atomic processes in the α → γ phase transition in iron. [ABSTRACT FROM AUTHOR]

The results of an experimental-theoretical study of the effect of thin-film coatings on residual microstrains, microstresses, and local microdistortions of the atomic structure of powder tungsten mechanically activated in the centrifugal ball mill have been presented. It has been shown that microdistortions of the crystal structure of different system-hierarchical levels arise in the surface-oxidized powders, which increase with an increase in the time of the activation process. It has been shown that this should lead to a significant increase in the reactivity of the mechanically activated powder tungsten. In contrast, the adsorption films that plasticize the near-surface layer of particles can decrease the efficiency of the mechanoactivation process of the tungsten powder. [ABSTRACT FROM AUTHOR]

The influence of dehydration on the position of sodium and cesium cations obtained by ion exchange in the structure of FAU(Y) was studied by powder X-ray diffraction using synchrotron radiation and 23Na and 133Cs magic-angle spinning NMR spectroscopy. The sodium and cesium cations were found to be mobile in the hydrated samples. In dehydrated zeolites CsNaFAU(Y), cesium is predominantly localized in four crystallographic ion-exchange positions located in the large cavities and sodalite cages. [ABSTRACT FROM AUTHOR]

The structures of nine ternary intermetallic compounds (IMCs) of the cerium—rhodium—gallium system containing 50 at.% rhodium were determined by single-crystal X-ray diffraction. The compounds are built up of alternating Ce2Rh3Ga fragments with the Mg2Cu3Si (MgZn2 type) or Mg2Ni3Si (MgCu2 type) structure and CeRh3Ga2 fragments with the CeCo3B2 (CaCu5 type) structure and form a homologous series of the composition R2+nT3+3nM1+2n (n = 0—5). These compounds can be classified into trigonal (R-3m) or hexagonal (P63/mmc) branches depending on the Laves phase-type fragment. [ABSTRACT FROM AUTHOR]

The localization and distribution of germanium atoms in the framework positions of Ge-BEC zeolite upon silylation have been studied using synchrotron XRD and 19F NMR. The high thermal stability of Ge-BEC material synthesized using 1-benzyl-1,4-diazabicyclo[2.2.2]octane as the structure-directing agent (SDA) has been observed, enabling the preparation of calcined Ge-BEC. Unexpectedly, the inhomogeneous enrichment of double-four membered ring (d4r) subunits in the BEC structure with germanium has been observed. The interaction of germanosilicate with (NH4)2SiF6 led to the selective substitution of germanium atoms in T2 and T3 positions with silicon, while fluoride anions preferably occupy positions inside d4r subunits. [ABSTRACT FROM AUTHOR]

An autocorrelation method is developed for determining the composition and decay time of scintillators. This method also allows studying the spatial distribution of nuclear radiation and controlling the amount of the dopants introduced in the scintillator. The decay time is measured from a few nanoseconds to microseconds. It is found out that the decay time increases in plastic scintillators with a wavelength shifter and a Gd doped. [ABSTRACT FROM AUTHOR]

New optically active derivatives of terephthalic acid, which are of interest as precursors of chiral metal-organic frameworks (MOFs), were synthesized starting from available dimethyl 2-aminoterephthalate, N-Boc- l-alanine, and N-Boc- l-proline. The crystal structures of three samples were determined by powder X-ray diffraction. In all three structures, the acid molecules exist as zwitterions. [ABSTRACT FROM AUTHOR]

A technology of perovskite-type LiNaTaNbO ceramic solid solutions based on sodium and lithium niobates and tantalates and a method of their ultrafast quenching have been presented. The influence of quenching on the structure of ceramic samples and the variations in crystallographic and fine structure parameters have been studied. It has been found that ultrafast quenching results in a preferred orientation of crystallites, severe local microstrains, and changes in the atomic structure of LiNaTaNbO ceramics. [ABSTRACT FROM AUTHOR]

Software that is required for the preliminarily analysis and mathematical processing of large neutron diffraction data arrays obtained when studying transient processes in crystals is developed. It includes programs for the visualization of 2D information arrays obtained using neutron TOF (time-of-flight) diffractometers with the time-of-flight scanning of spectra and a program package that makes it possible to analyze changes in the atomic structure of a sample during the transient process in the automatic mode. The results of this analysis are dependences of the structural characteristics of crystallographic phases existing or produced during phase transitions on the time (or on the external conditions). If required, it is possible to perform the analysis of data measured using diffractometers with a monochromatic neutron beam and the scattering- angle scan by means of application of the program package. [ABSTRACT FROM AUTHOR]

Neutron diffraction studies of the FeAl compound are performed in a wide temperature range (20-900°C) in order to determine its structural states and the mechanism of ordering of atoms. The combination of high-resolution diffraction and the real-time detection of diffraction spectra makes it possible to establish that, in contrast to traditional notions, the structure of this compound at room temperature is a phase with only a partially ordered arrangement of Fe and Al in a unit cell. A completely ordered phase (such as FeAl) is present in the form of mesoscopic (~200Å) clusters coherently incorporated into the disordered matrix of the main phase. After the transition of the sample to a disordered state ( T> 740°С) and slow cooling to room temperature, the size of structurally ordered clusters increases to ~900 Å. A high contrast in the coherent neutron scattering lengths of iron and gallium nuclei allows the accurate determination of the temperature dependence of the occupancy factors of sites by Fe and Al atoms up to a phase transition to the disordered state. [ABSTRACT FROM AUTHOR]

Neutron diffraction was employed in order to determine microdeformations in samples of stainless austenitic dispersion-hardened steels subjected to the action of high temperatures (to 700°С) during different times (up to 12 h). Experiments were conducted on a high-resolution neutron diffractometer using the timeof- flight method. The analysis performed showed systematic changes in the parameters and microdeformations of the crystal lattice. The high level of the diffractometer resolving power made it possible to reveal some important additional details of the microstructure of dispersion-hardened steels as compared to the results obtained earlier on a diffractometer with monochromatic neutron beam. [ABSTRACT FROM AUTHOR]

With reaching extremely high intensities of heavy-ion beams, new requirements for the detection system of the Dubna Gas-Filled Recoil Separator (DGFRS) will definitely be set. One of the challenges is how to apply the 'active correlations' method [1-6] to suppress beam associated background products without significant losses in the whole long-term experiment efficiency value. Different scenarios and equations for the development of a method according to this requirement are under consideration in the present paper. [ABSTRACT FROM AUTHOR]

Novel nanohybrid materials were prepared by immobilizing Co nanoparticles on a microporous framework MIL-53(Al) as a porous host matrix. The synthesized cobalt-containing materials were characterized by XRD, STEM, and oxygen titration. The catalytic performance of Co@MIL-53(Al) nanohybrids was examined in Fischer–Tropsch synthesis (FTS) for the first time. A higher selectivity to C5+ hydrocarbons and lower selectivity to methane for Co@MIL-53(Al) as compared to conventional Co/Al2O3 were observed. [ABSTRACT FROM AUTHOR]

La1- xSr xFe2/3Mo1/3O3 (0 ≤ x ≤ 1) perovskites allow exceptionally wide tuning of the Mo oxidation state from +3 ( x = 0) to +6 ( x = 1) with the FeIII oxidation state virtually unchanged. The end members of this series show antiferromagnetic ordering in LaFe2/3Mo1/3O3 at TN = 520 K and ferrimagnetic ordering in SrFe2/3Mo1/3O3 at TC = 420 K. The crucial role of electron correlations in the Mo 4d shell suggests that LaFe2/3Mo1/3O3 with a half-filled band is a Mott insulator, whereas SrFe2/3Mo1/3O3 is a band insulator. In both cases, the magnetic structure is dictated by antiferromagnetic superexchange between localized magnetic moments. At intermediate compositions, an interplay of antiferromagnetic-superexchange and double-exchange interactions results in nonmonotonous variations of both the magnetic-ordering temperature and saturation magnetization. [ABSTRACT FROM AUTHOR]

A specialized diffractometer intended for use in studying real-time transient processes in condensed media, which also allows the recording of Bragg diffraction and small-angle neutron scattering spectra, has been created at the Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research. Frequently, only the given formulation of the experiment with the continuous recording of information on the process enables us to obtain data required for the correct interpretation of events. One of the crucial parameters of such experiments is the minimal time interval in which sufficient statistics can be acquired. The diffractometer parameters make it possible to measure diffraction and small-angle spectra within minute and even second (for certain types of transition processes) ranges. The possibilities of neutron scattering are discussed as applied to the study of transient processes, the diffractometer design is described, and its main characteristics and the test experiment results are presented. [ABSTRACT FROM AUTHOR]

The study of barium ferrites partially substituted by diamagnetic Al and In ions has been performed by the neutron diffraction method with high resolution. Both samples BaFe D O ( $ D=Al$ and In) preserve a magnetoplumbit structure in a broad temperature range from 4.2K to 730K. The Invar effect was found in the low-temperature region in both samples. This unusual behavior of the unit cell was explained by changes of the regime of mutual rotations and tilts of the oxygen octahedra. The magnetic structure described by the Gorter model is saved up to the ferrimagnetic and paramagnetic phase transition temperature, 705K and 695K, for the Al- and In-substituted ions, respectively. The substitution of iron by aluminum or indium ions decreases the total magnetic moment of the investigated composition from $ 20 \mu_{B}$ (BaFeO) to 19 and $ 16.7 \mu_{B}$ , respectively. A higher coercitivity was found $ H_{c}\sim 0.1$ T, for the In-substituted compositions, differently from $ H_{c}\sim 0.007$ T of the Al-doped ones because of the frustration of the magnetic structure. The decrease of ambient temperature increases microstresses in crystallites because of the increasing influence of the magnetic subsystem. [ABSTRACT FROM AUTHOR]

The crystal structure of iron-doped barium titanate BaTiFeO is studied by neutron diffraction in the range of 0 ≤ x ≤ 0.12. At low concentrations of iron, x < 0.01, and at room temperature, these compounds have a polar structure with tetragonal symmetry with space group P4 mm. The temperature of the transition of the tetragonal ferroelectric phase into the cubic paraelectric phase with space group Pm $$\bar 3$$ m for an iron concentration of x = 0.01 is 390 K (for pure BaTiO, it is 410 K). At an iron concentration of x = 0.07, the crystal structure of the studied compounds varies, and it is described by the centrosymmetric hexagonal space group P6/ mmc. The structural parameters of various phases of compound BaTiFeO are determined from the experimental data. [ABSTRACT FROM AUTHOR]

With reaching to extremely high intensities of heavy-ion beams new requirements for the detection system of the Dubna Gas-Filled Recoil Separator (DGFRS) will definitely be set. One of the challenges is how to apply the 'active correlations' method to suppress beam associated background products without significant losses in the whole long-term experiment efficiency value. Different scenarios and equations to develop the method according this requirement are under consideration in the present paper. The execution time to estimate the dead time parameter associated with the optimal choice of the life-time parameter is presented. [ABSTRACT FROM AUTHOR]

The possibility of formation of the mixed matrix membranes NH-MIL-101(Al) under the conditions of microwave activation of the reaction mixture at atmospheric pressure is studied. Microwave irradiation affects the morphology and crystallite size and significantly shortens the synthesis time (from tens of hours to 10-30 min). The obtained samples of NH-MIL-101(Al) with a crystallite size of 100 nm were used as nanofillers for polymer matrix based on the PIM-1 polymer with intrinsic microporosity for the preparation of hybrid membrane materials. Gas permeability for a series of gases was measured on the synthesized membranes. [ABSTRACT FROM AUTHOR]

Neutron and X-ray diffraction methods have been applied jointly to study the crystal structure of the ordered phase of VC in macro- and nanocrystalline vanadium carbide powders. The deviation of the composition of the ordered VC phase from the stoichiometric composition VC has been established. The magnitudes and directions of the displacements of C and V atoms have been determined. It has been shown that vanadium atoms are displaced towards a vacancy, increasing the electron density of the vacancy position of the carbon sublattice. [ABSTRACT FROM AUTHOR]

The reactions of CuSO4 ·5H2O and Ba(R2mal) [R2mal2- is the dianion of 1,1-cyclopropanedicarboxylic acid (H2Cpdc), 1,1-cyclobutanedicarboxylic acid (H2Cbdc), or butylmalonic (H2Bumal) acid] in water give crystals of the 3D coordination polymers [BaCu(Cpdc)2] n ( 1), [BaCu(Cbdc)2(H2O)] n ( 2) and [Ba3Cu3(Bumal)6(H2O)11] n ·2 n(H2O) ( 3). The heating of 2 in air to 200 °C for 60 min results in the removal of the coordinated water molecules to give anhydrous [BaCu(Cbdc)2] n ( 4). The structures of 1- 3 were determined by single-crystal XRD, and that of 4 was derived from powder XRD (XPRD) data. It was assumed that the crystal structures of the polymer complexes that we isolated were determined, to a considerable extent, by the nature of the substituent of the dicarboxylic acid. For 2, the dicarboxylic acid contains closed cyclic moieties, which are retained during dehydration to give 4. A comparative study of the thermal decomposition processes and thermal kinetics of 1- 3 showed that the dehydration proceeds by a single scheme, and the bonds between the structural moieties in the anhydrous intermediates become stronger. The thermal destruction of the anhydrous compounds 1, 4 and { 3} [the dehydrated intermediate of the thermal decomposition of 3, as proved by thermogravimetric analysis (TGA) data] occurs above 170 °C. The phase compositions of their solid products are determined by the thermolysis conditions, and the formation of BaCuO2 from 3 can be realized under milder conditions than those for the formation from 1 and 2. [ABSTRACT FROM AUTHOR]

We performed an experimental search for the bound state singlet deuteron predicted in some microscopic calculations. The predicted energy of this level is in vicinity of the deuteron disintegration threshold. This state should manifest itself in two-photon $$^3 \tilde S_1 \to ^1 S_0 \to ^3 S_1$$ transition following thermal neutron capture by protons. The experiment consists in the search for the second gamma-ray in the cascade through a high statistics measurement of γ-ray spectra after thermal neutron capture by hydrogen nuclei. The upper limit 15 μb is obtained for the cross section of the singlet deuteron production with the bound energy in the range 25-125 keV. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structures of TlFeS and TlFeSe chalcogenides are studied by neutron diffraction in the temperature range 10-300 K. The investigated compounds feature monoclinic crystal symmetry with the C2/m space group. Antiferromagnetic ordering occurs in TlFeS and TlFeSe at the Néel temperature T = 210(5) and 295(5) K, respectively. The temperature dependences of magnetic moments, Fe-Fe bond lengths, and unit-cell volume are established. The coefficients of thermal expansion for the paramagnetic and antiferromagnetic phases are calculated. [ABSTRACT FROM AUTHOR]

The paper discusses further development of the approach published in Comp. Phys. Comm. vol. 185(2014), 933-938 (2014). Low statistics means a little of information about the object of interest so that a more or less exact parameter estimation and reliable statistical tests can be only a matter of chance, especially in the case of the exponential distribution which is more intolerant to small samples (1-4 events) than the majority of other important distributions. Therefore, the problem of optimization of the statistical analysis is especially actual for the exponentially distributed data and the paper suggests, for both the parameter (mean) estimation and the statistical tests, a concept of a confidence interval, based on the order statistics, which, on the one hand, provides its clear and natural interpretation, and, on the other hand, is an optimum compromise between the criteria: 'the shortest interval length'-'the largest size of the probability.' [ABSTRACT FROM AUTHOR]

An ultrasonic method is used to study the onset of ion transport inlithium oxides in a ceramic of the Li–Si–Ge–As–S–O system. The onset temperature for ion transport estimated from the temperature dependence of the relative change in the propagation speed of ultrasound is the same as that obtained by other methods, which indicates that the ultrasonic method is applicable to studies of the onset of ion conductivity inlithium oxide semiconductors. © 1999 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Broadening of the diffraction reflections in nanocrystalline powders of nonstoichiometric niobium carbide NbC with the average particle size from ∼200 to ∼2000 Å has been studied by the neutron diffraction method. The functional dependence of the broadening W on the interplanar distance d has been obtained including size, deformation, and inhomogeneous broadening. The average size of the coherent scattering regions and microstrains in crystallites with allowance for the anisotropy of the deformation distortions have been estimated. [ABSTRACT FROM AUTHOR]

The structural study of barium hexaferrite (BaFeO) whose iron ions are partly replaced by diamagnetic aluminum ions ( x = 0.6) is carried out with the help of the neutron-diffraction method. Experimental data are acquired in a wide temperature range of 4-730 K via a high-resolution diffractometer, which makes it possible to obtain both precise information on changes in crystalline and magnetic structures and behavioral data on the sample microstructure. BaFeAlO retains the magnetoplumbite structure in the whole temperature range and exhibits the 'invar effect,' according to which its bulk thermal-expansion coefficient is close to zero at low temperatures (<150 K). The magnetic structure is defined by the Gorter model with magnetic moments oriented along the hexagonal axis. For all nonequivalent crystallographic positions, the magnetic moment of F is close to 4 μ at 4 K. The total magnetic moment per formula unit is 15.6 μ, i.e., less than the nominal value of 20 μ. This is caused by the fact that diamagnetic Al ions are included in the composition. Crystallite microstrains increase insignificantly with temperature due to increasing influence of the magnetic subsystem. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structures of anion-deficit cobaltite LaBaCoO have been studied by the X-ray and neutron diffraction methods at high pressures up to 30 and 6 GPa, respectively. A structure transition from the cubic phase with symmetry $Pm\bar 3m$ to the tetragonal phase with symmetry P4/ mmm has been observed in this compound at P ≈ 3 GPa. It is accompanied by the change of the ground antiferromagnetic state of the G type to the ferromagnetic state because of a change in the electronic configuration of Co ions. Possible mechanisms of the observed magnetic phase transition, as well as the role of the superexchange interactions between Co ions in various spin states in the formation of magnetic properties, have been discussed. Pressure-induced change in the magnetic state of LaBaCoO significantly differs from related stoichiometric compounds LaACoO (A = Sr, Ca), where the ground ferromagnetic state is formed and the sign of the pressure dependence of the Curie temperature depends on the element A. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structures of TlFeS and TlFeSe are studied by neutron diffraction in the temperature range of 10-320 K. The structures of TlFeS and TlFeSe have monoclinic symmetry with the space group C2/ m at room temperature. TlFeS displays an antiferromagnetic phase at temperature below 200 K. The antiferromagnetic phase transition in TlFeSe takes place at a temperature below 290 K. The temperature dependence of the unit-cell parameters and volume are obtained. The coefficients of thermal and linear expansion are calculated. The temperature dependences of the interatomic distances are presented. [ABSTRACT FROM AUTHOR]

The new ceramic compounds type 4 (where = and ) have been reported for the first time. The sample was prepared by solid-state reaction technique. The orthorhombic crystallization with a = 6.429(4) Å, b = 6.536(5) Å, c = 8.648(4) Å for 4 and a = 6.485(3) Å, b = 6.561(4) Å, c = 8.686(4) Å for 4 was studied from powder X-ray diffraction studies. The semiconducting nature of the compounds was observed with the energy gap measurement from diffused reflectance spectroscopy (DRS) studies. The paramagnetic nature of the compounds at room temperature and low temperature conditions was identified by magnetization measurements as a function of magnetic fields and temperature. The effective magnetic moment of the samples was found to be 2.126 μB and 4.272 μB. [ABSTRACT FROM AUTHOR]

The structures of Tamerit® ( A) and Galavit® ( B) pharmaceutical preparations have been solved by X-Ray single crystal and powder diffraction. These are luminol sodium salts possessing immunomodulatory and anti-inflammatory properties. It is shown that Tamerit® ( A) is a hydrated salt, while Galavit® ( B) is a mixture of two polymorphic modifications ( B1 and B2) of anhydrous salt. Compound A is crystallized in a monoclinic system: a = 8.3429(4) Å, b = 22.0562(11) Å, c = 5.2825(2) Å, β = 99.893(3)°, V = 957.59(8) Å, and Z = 4; sp. gr. P2/ c. Compound B1 is crystallized in a monoclinic system: a = 14.7157(18), b = 3.7029(19), c = 16.0233(15) Å, β = 116.682(13)°, V = 780.1(4) Å, and Z = 4; sp. gr. P2/ c. Compound B2 is crystallized in an orthorhombic system: a = 27.7765(15) Å, b = 3.3980(19) Å, c = 8.1692(19) Å, V = 771.0(5) Å, and Z = 4; sp. gr. Pna2. The absence of phase transitions between the B1 and B2 polymorphs has been established by differential scanning calorimetry. [ABSTRACT FROM AUTHOR]

Anomalous temperature dependences of Young's modulus were observed in the as-cast and directionally solidified Fe100-xGax alloys (x = 20, 22, 24, 27). However, the absence of the anomalous temperature dependence of Young's modulus in the DO19 and L12 ordered Fe73Ga27 alloys revealed that the anomalous temperature dependences of Young's modulus of Fe-Ga alloys with different structures were only related with the structure transformation during the heating process. The relationship between the variations of Young's modulus and structural transformation in the Fe78Ga22 alloy indicated that the lattice shrinkage owing to the structural transformations of A2 → DO3 and BCC(A2/DO3) → L12 was offset by the lattice expansion of the A2 phase caused by the thermal effect, which lead to a near constant coefficient of Young's modulus in the temperature range from 500 °C to 560 °C. In addition, the variability of Young's modulus as high as 12.8% was obtained in the as-directional solidified Fe73Ga27 alloy. [ABSTRACT FROM AUTHOR]

This paper reports selective synthesis of two iodine-containing TTF (tetrathiafulvalene) salts: one, (TTF)11I8, is a new molecular conductor while another is the known non-conducting (TTF)I3 compound. Single crystals of both salts were prepared using different amounts of iodine in the redox process between TTF and I2. X-ray data showed that the resulting conducting (TTF)11I8 salt might be considered as a new modulated phase of the non-stoichiometric (TTF)I0.7+δ salts. The electrical resistance of single crystals of (TTF)11I8 reveals a semiconducting-like behaviour. The paper presents also a study of electromechanical properties of organic conductive bi-layer (BL) films prepared by covering different organic polymeric films with a thin network of oriented submicrocrystals of (TTF)I0.7+δ phases. These BL films exhibit a combination of flexibility, lightweight, and high piezo-resistivity properties showing therefore a potential interest for electronic sensing applications where lightweight, large area coverage and flexibility are required. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structures and the vibrational spectra of PrSrMnO manganite are studied within the pressure range up to 25 GPa by methods of X-ray diffraction and Raman spectroscopy. Neutron diffraction studies have been performed at pressures up to 4.5 GPa. The magnetic phase transition from the ferromagnetic phase ( T = 273 K) to the A-type antiferromagnetic phase ( T = 153 K) is found at P ≈ 2 GPa. This transition is characterized by a broad pressure range corresponding to the phase separation. The Raman spectra of PrSrMnO measured under high pressures significantly differ from the corresponding spectra of the isostructural doped AA′MnO manganites, (where A is a rare-earth ion and A′ is an alkaline-earth ion) with the smaller average ionic radius 〈 r〉 of A and A′ cations. Namely, the former spectra do not include clearly pronounced stretching phonon modes. At P ∼ 7 GPa, there appears the structural phase transition from the orthorhombic phase with the Pnma space group to the orthorhombic high-pressure phase with the Imma symmetry. In the vicinity of the phase transition, anomalies in the pressure dependences of the lattice parameters, unit cell volume, and phonon frequencies corresponding to the characteristic lattice vibration modes are observed. [ABSTRACT FROM AUTHOR]

X-ray diffraction data on powder and single-crystal samples were used to determine the crystal structure of hydrogen-bis[2-(4-dimethylaminostyryl)-quinoline-1-oxide]dichlorocuprate (I): monoclinic system, sp. gr. P2/ n, and Z = 2. Two molecules of N oxide of 2-(4-dimethylaminostyryl)quinoline are bound through a hydrogen atom located at the center of symmetry, thus forming a complex cation. [ABSTRACT FROM AUTHOR]

A concept for the IRM fast periodic-pulse reactor, which can be used as an ignition module for high-power nuclear-pumped lasers, is presented. The periodic-pulse operating regime of IRM is examined. The results of calculations of the parameters of the IRM which is under development are compared with the main characteristics of IBR-2. It is shown that IRM holds promise for use in high-power nuclear-pumped lasers. [ABSTRACT FROM AUTHOR]

The reaction of zinc( ii) acetate hydrate with pivalic acid (HOOCBu = HPiv) in air at 100 °C afforded the new 1D coordination polymer {Zn(Piv)} ( 1), in which the metal atoms are in a tetrahedral ligand environment. The thermal behavior of the resulting compound and the sublimation and vaporization processes in the temperature range of 430-550 K were studied by differential scanning calorimetry and thermogravimetric analysis. The structure of compound 1 was determined by X-ray powder diffraction. [ABSTRACT FROM AUTHOR]

Novel hydrazones were obtained from thiooxamohydrazides and 3-3-formyl-4-hydroxycoumarin. According to data from NMR spectroscopy and X-ray diffraction, the coumarin fragment in the compounds obtained exists as 4-hydroxycoumarin or chromane-2,4-dione. When dissolved in dimethyl sulfoxide, these hydrazones undergo fragmentation into derivatives of 1,3,4-thiadiazole and 4-hydroxycoumarin. [ABSTRACT FROM AUTHOR]

The ion-selective properties of 1,5-bis[2-(hydroxyethoxyphosphoryl)phenoxy]-3-oxapentane HR have been described. The molecular and crystal structure of HR has been determined by powder X-ray crystallography and IR spectroscopy. The molecule has the twofold symmetry axis, orthorhombic crystal system, space group Pbcn, a = 16.830(2) Å, b = 8.866(15) Å, c = 15.7190(2) Å, V = 2346.1(6) Å, Z = 4. A new CuR · 2HO complex has been synthesized and characterized. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structure of PrSrMnO manganite has been studied by the neutron diffraction at high pressures up to 5 GPa in the temperature range 10-295 K. At normal pressure and decreasing temperature the appearance of the C-type ( T = 220 K) and G-type ( T = 180 K) antiferromagnetic states occurs, which is accompanied by a structural phase transition from the cubic structure ( Pm $$ \bar 3 $$ m space group) to the tetragonal structure ( I4/ mcm space group). It is shown that the temperature of the transition to the C-type antiferromagnetic phase increases with pressure with the pressure coefficient dT/ dP = 4.0(5) K/GPa and the temperature of the transition to the G-type antiferromagnetic phase weakly depends on pressure. [ABSTRACT FROM AUTHOR]

This article is devoted to the synthesis and examination of the electrical properties of amorphous chalcogenides AgGeAsS ( x = 0.1, 0.4-0.6, 0.9) at low temperatures. The studies are performed in order to obtain materials with improved characteristics (an increase in the fraction of the ionic transfer, a decrease in the temperatures of its emergence, and an increase in conductivity). The synthesized compounds are electron-ion conductors. An increase in the Ge fraction leads to an increase in the temperature corresponding to the onset of ionic transport and to a decrease in conductivity. [ABSTRACT FROM AUTHOR]

The crystal and magnetic structure and the Raman spectra in PrBaMnO manganite have been studied by the neutron diffraction technique at pressures up to 5 GPa as well as by the X-ray diffraction and Raman spectroscopy at pressures up to 30 GPa. The pressure dependence is determined for the lattice parameters, unit cell volume, Mn-O bond lengths in the orthorhombic structure of the Imma symmetry, and bending and stretching vibration modes for oxygen octahedra. In the low-temperature range at pressure P = 1.9 GPa, the magnetic transition from the initial ferromagnetic (FM) ground state ( T = 197 K) to the A-type antiferromagnetic (AFM) state ( T = 153 K) has been revealed. The FM and AFM phases coexist at pressures up to 5.1 GPa and exhibit negative and positive values of the pressure coefficient for the Curie and Néel temperature, respectively ( dT/ dP = −2.3 K/GPa and dT/ dP = 8 K/GPa). The pressure dependence of the Curie temperature in PrBaMnO differs drastically from that observed in other manganites of nearly the same composition with the orthorhombic Pnma and rhombohedral $R\bar 3c$ structures, where the FM phase is characterized by the positive values of dT/ dP. The structural mechanisms of these phenomena are discussed. [ABSTRACT FROM AUTHOR]

The results of neutron diffraction studies of the LaSrMnO compound and its behavior in an external magnetic field are stated. It is established that in the 4-300 K temperature range, two structural perovskite phases coexist in the sample, which differ in symmetry (groups $$R\bar 3c$$ and I4/ mcm). The reason for the phase separation is the clustering of oxygen vacancies. The temperature (4-300 K) and field (0-140 kOe) dependences of the specific magnetic moment are measured. It is found that in zero external field, the magnetic state of LaSrMnO is a cluster spin glass, which is the result of frustration of Mn-O-Mn exchange interactions. An increase in external magnetic field up to 10 kOe leads to fragmentation of ferromagnetic clusters and then to an increase in the degree of polarization of local spins of manganese and the emergence of long-range ferromagnetic order. With increasing magnetic field up to 140 kOe, the magnetic ordering temperature reaches 160 K. The causes of the structural and magnetic phase separation of this composition and formation mechanism of its spin-glass magnetic state are analyzed. [ABSTRACT FROM AUTHOR]

The crystal structure and vibrational spectra of deuterated pyridinium perchlorate ( dPyH)ClO (CDNHClO) are studied by means of neutron diffraction in ambient conditions, X-ray diffraction at high pressures up to 3.5 GPa in the temperature range 297-420 K, and Raman spectroscopy at high pressures up to 5.7 GPa. Deuterated pyridinium perchlorate at ambient conditions has rhombohedral structure with the R3 m symmetry (paraelectric phase I). Over the pressure range of 0.5-1.2 GPa, the phase II with monoclinic symmetry Cm exists. At pressure P ∼ 1.2 GPa, the phase transition to monoclinic phase III with the Pm symmetry is observed at ambient temperature. The lattice parameters, unit cell volume, and frequencies of internal vibrational modes as functions of pressure are obtained for different phases of deuterated pyridinium perchlorate. The P-T phase diagram of ( dPyH)ClO over the extended pressure and temperature range is discussed. [ABSTRACT FROM AUTHOR]

The behavior of the running coupling constant α( Q) phenomenologically parameterized in the region of Q < 1 GeV is considered within the framework of the Poincare-covariant quark model in a variety of regimes. An analysis was carried out for pseudoscalar and vector mesons with the lepton masses and decay constants (obtained by the model calculations) required to match their experimental counterparts. It shows that the constant α is likely to behave with α = α( Q = 0) ∼ 0.667 − 0.821 in the case of a frozen regime and α =0.300 − 0.692 for peaked curves, which follows from the experimental values of the leptonic decay constants and masses. [ABSTRACT FROM AUTHOR]