Impact and Friction Sensitivity of Energetic Materials：Methodical Evaluation of Technological Safety Features

Key methods developed and used in the USSR and in the Russian Federation to determine the impact and friction sensitivity of energetic materials and explosives have been discussed.Experimental methodologies and instruments that underlie the assessment of their production and handling safety have been described.Studies of a large number of compounds have revealed relationships between their sensitivity parameters and structure of individual compounds and compositions.The range of change of physical and chemical characteristics for the compounds we examined covers the entire region of their existence.Theoretical methodology and equations have been formulated to estimate the impact and friction sensitivity parameters of energetic materials and to evaluate the technological safety in use.The developed methodology is characterized by high-accuracy calculations and prediction of sensitivity parameters.

Influence of structural factors on the strength properties of aluminum alloys under shock wave loading

The results of measurements of the strength characteristics-Hugoniot elastic limit and spall strength of aluminum and aluminum alloys in different structural states under shock wave loading are presented.Single-crystals and polycrystalline technical grade aluminumА1013 and aluminum alloysА2024,АА6063Т6,А1421,A7,А7075,А3003,A5083,АА1070 in the initial coarse-grained state and ultrafine-grained or nanocrystalline structural state were investigated.The refinement of the grain structure was carried out by different methods of severe plastic deformation such as Equal Chanel Angular Pressing,Dynamic Channel Angular Pressing,High-Pressure Torsion and Accumulative Roll-Bonding.The strength characteristics of shock-loaded samples in different structural states were obtained from the analysis of the evolution of the free surface velocity histories recorded by means of laser Doppler velocimeter VISAR.The strain rates before spall fracture of the samples were in the range of 10^(4)-10^(5 )s^(-1),the maximum pressure of shock compression did not exceed 7 GPa.The results of these studies clearly demonstrate the influence of structural factors on the resistance to high-rate deformation and dynamic fracture,and it is much less than under the static and quasi-static loading.

New interpretation of experimental data on Si-As alloy solidification with planar interface

An analytical model was developed to describe Si？As alloy solidification in the whole range of measured interface velocity. It is demonstrated that at low interface velocity, the solidification occurs in the initial transient regime. The model leads to good comparison with the experimental data taking both local nonequilibrium effects at high interface velocity and steady state effects at low interface velocity into account. The local nonequilibrium diffusion effects shrink the initial transient period and lead to diffusionless solidification at high interface velocity.

Estimation of the Ballistic Effectiveness of 3,4-and 3,5-Dinitro-1-(trinitromethyl)-1H-Pyrazoles as Oxidizers for Composite Solid Propellants

The experimental values of the enthalpy of formation of two isomeric 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles have been obtained(261.5±5.0and 246.4±6.7kJ/mol for crystalline 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles,respectively).The ballistic effectiveness of these potential oxidizers in composite solid propellants was studied.It is shown that these two oxidizers may be successfully applied in metal-free compositions or with a small content of metal.For the bottom stage 3,4-dinitro-1-(trinitromethyl)-1H-pyrazole is a bit better than 3,5-dinitro-1-(trinitromethyl)-1H-pyrazole,for the upper stage the both oxidizers show the equal ballistic parameters.These oxidizers allow to create metal-free solid composite propellants with the binder percentage not lower than 19%(volume fraction),with I3spequal to 256.5-257.0sat density equal to 1.72-1.74g/cm^3.

Magnetic Control of the Earthquakes

Many observations reliably exhibit correlations between the magnetic perturbations and seismic responses, convincing that the magneto-seismicity is not a myth. Magnetic control of the earthquakes is based on physics of magneto-plasticity, the remarkable phenomenon, which implies generation of the electron spin pairs on the trapped dislocations, in which Coulomb interaction is switched off. Microwave irradiation at Zeeman frequencies in these pairs stimulates the motion of dislocations, inducing release of elastic energy into the safe plastic deformation. Magneto-seismic correlations unambiguously demonstrate that the earthquakes are indeed suppressed by low-frequency (wide and continuous spectrum from Hz to MHz) microwaves The detailed mechanism of this phenomenon is discussed and experimental proofs are given in terms of magneto-plasticity as a feasible means to control earthquakes.

Dependence of Specific Impulse of Metal-free Formulations on CHNO-oxidizer′s Element Content and Enthalpy of Formation

It is shown that it is not correct to estimate energetic characteristics of different compounds of solid composite propellants by evaluation of the specific impulse values of these components serving as an only component in the formulation.Such an approach may turn the researcher to a wrong conclusion.One has to compare compound′s potential in formulations close to real,e.g.at least with necessary amount of binders.Dependences of specific impulse upon element content of highenthalpy CHNO oxidizer,its enthalpy of formation,and kind of binder have been found.

Energetic Abilities of Solid Composite Propellants Based on 3,4,5-Trinitropyrazole and Ammonium Dinitramide

The investigation aims at the expansion of the basis of formulations of solid composite propellants by introducing new compositions with lower sensitivity to mechanic impact and improved thermal stability.The formulations based on trinitropyrazole(TNP)contains a binder(a hydrocarbon or active one),aluminum and inorganic oxidizer ADN.The results show that a binary formulation TNP+active binder(18%-19%)(volume fraction)with no metal is well designed which would achieve high specific impulse(at Pc∶Pa=40∶1)of 248s,high density of 1.80g/cm3 and combustion temperature Tcabout 3 450K.In terms of energy,metal-free compositions with TNP lose a bit to those with HMX,only if HMX fraction in formulation is higher than 45%-50%.

3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine.Structure and energy abilities as a component of solid composite propellants

The work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBTAT),first obtained by the authors in 2020.NBTAT compound crystallizes in the monoclinic system,space group P2(1)/n,density at room temperature 1.939 g/cm^(3).The energies of crystal packing and pairwise intermolecular interactions in NBTAT and its unnitrated analogue BTAT were calculated,and their comparative analysis was carried out.The enthalpy of formation of NBTAT molecules was calculated by quantum-chemical methods using Gaussian 09,and the enthalpy of formation of NBTAT in the solid phase(618 kJ/mol)was estimated.The energy capabilities of NBTAT as an oxidizer of solid composite propellants are estimated.It is shown that in metal-free compositions NBTAT is significantly superior to ammonium perchlorate(AP),dinitramide ammonium salt(ADN),HMX,BTAT at all stages of rocket systems,and is comparable to the superdense CL-20 yielding to the latter at the lower stages and slightly winning at the upper stages.

Energetic Opportunities of Solid Composite Propellants Containing Some Hypothetic Furazano-[3,4-d]-pyridazine-based Derivatives

Six furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants have been investigated.It was shown that the use of some furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants can considerably increase ballistic parameters compared with HMX if the compounds under consideration contain difluoramine groups.And the use of the compounds under consideration may be successful only in the presence of an active binder and 10%-30% of AP or ADN as additional oxidizers.

The reaction of the iron thiosulfate-nitrosyl complex with adenosine triphosphoric acid

Iron tetranitrosyl complex bearing the thiosulfate ligand (TNIC) is an efficient nitrogen monoxide donor (NO). He shows antitumor properties and may be used as an original drug for the therapy of acute coronary syndrome. In this work, the reaction of the TNIC with adenosine triphosphoric acid (ATP) was studied. Formation of the products for the reaction of ATP with TNIC was shown by electronic microscopy. The kinetics of the reaction was controlled by spectrofluorometric method, and the complexation constant was measured. The mechanism of interaction of ATP with TNIC was proposed, and the relevant kinetic model satisfactorily described the experimental data, which permitted to calculate the rate constants for these process stages. NMR, IR, and M?ssbauer studies were used for determination of the reaction product structure. NMR study showed TNIC interaction only with adenine part of ATP. The method of IR spectroscopy identified both the absence NO in the reaction products and the occurrence of new Fe-S and Fe-N bonds. M?ssbauer study showed that iron in the reaction products was presented by two forms: Fe(II) and Fe(III). Thus, the structures for the [ATP-Fe2+S] and [ATP-Fe3+S] complexes were proposed.

Influence of Low-Frequency Sonolysis on the Stability of Reactions Involving Associates

The influence of low-frequency sonolysis on the kinetics bimolecular liquid-phase reactions was studied with due regard for the association (dimers and trimers) of starting reagents. The mathematical modeling of chemical reactions that were described by nonlinear differential equations is performed. The steady states, the singular points characteristics, the nature of concentration oscillations in the reaction system are described. With increasing frequency and amplitude of low-frequency sonic waves (up to some critical value), we observed the cessation of the reaction. This observation offers an additional tool for controlling reaction rate by the external action of low-frequency vibrations. The conclusions of the work are obtained under certain assumptions. The exact determination of the critical conditions for changes in dynamics is beyond the scope of the problem.

Complexation with ATP as a Cause of Pollutants Toxicity to Aquatic Life

The toxicity of some pesticides, namely, Lontrel, Sencor, Roundup, Bentazon, and Hymexazol, and also Lontrel complexes with Cu, Co, Mn, Mg, Mo, Ni, and Zn that are being widely used in agriculture and, hence, abundant in the environment were characterized by biotesting. The variation in the enzymatic activity of the luminous bacteria Beneckea harveyi and in the reproductive function of the infusoria Tetrahymena pyriformis was measured and used to determine toxicity factors. The toxicity of the above compounds was found to correlate with their ability to form stable complexes with adenosine triphosphate (ATP).

Synthesis, characterization, spectroscopic and crystallographic investigation of metal complexes of N-benzyl-N-nitrosohydroxylamine

New metal complexes of N-benzyl-N-nitrosohy-droxylamine (BNHA) are isolated and characterized by elemental analysis, IR and UV-VIS spectroscopy. Spectrophotometric titration of aqueous solutions of BNHА by salts of some transition metals allowed to calculate the composition and formation constants of the metal complexes. The crystal structure of Cu (BNHА)2 is studied by X-ray diffraction. The Cu atom is coordinated by four O atoms of two bidentate ligands, which close 5-membered chelate rings. The N-O (1.306 ? - 1.320 ?) and N-N (1.274?? and 1.275? ) bond lengths indicate that π electrons are delocalized over the chelating groups. Complexes form stacks with intermolecular Cu…N contacts equal to 3.118?? and 3.306 ?.

Interaction of Hemoglobin with Binuclearcationic Tetranitrosyl Iron Complex with Penicillamine. Cations Binding Sites

In this paper, the kinetics of the interaction of the nitrosyl iron complex with the ligands penicillamine [Fe2(SC5H11NО2)2(NO)4]SO4·5H2O (I) with deoxyhemoglobin (Hb) was studied. The kinetic modeling method defined the number of binding (I) molecules and equilibrium constant of the coupling reaction of (Biomedicine, Iron-Sulfur Cluster, Ligand Binding, Heme, Nitric Oxide ) with Hb (Ks). At equimolar concentrations of (I) and Hb (2 × 10−5 M), the Hb molecule binds only one (I) with Ks equal to 4.3 × 107 M−1. When increasing the (Biomedicine, Iron-Sulfur Cluster, Ligand Binding, Heme, Nitric Oxide ) concentration, the number of binding sites of Hb increases and Ks decreases. These results are analyzed in accordance with the data on the existence of cations binding sites in Hb.

Electrophysical propertis of solid solutions of Zn_2–x(Ti_aZr_b)_1–xFe_2xО₄

Electrophysical properties of multicomponent system Zn2TiO4–Zn2ZrO4–ZnFe2O4 were investigated. The electrical conductivity, band gap, dielectric permittivity, and molar polarizability of formed solid solutions –Zn2-x(TiaZrb)1-xFe2xO4 (x = 0 - 1.0 are defined;Δх = 0.05;a + b = 1;a:b = 1:5;1:4;1:3;1:2;1:1;2:1;3:1;4:1) were defined. Electrophysical properties of samples are in linear dependence on their composition. All the synthesized samples are semiconductors with high electrical resistivity. Was confirmed the formation of two phases of variable composition with a wide homogeneity range.

Synthesis and Investigation of Pseudo Binary System CaTiSiO₅-YFeSnO₅

The research is devoted to the multicomponent system CaTiSiO5-YFeSnO5. The synthesis of solid solutions Ca1-xYxTi1-xSnxSi1-xFexO5 (x = 0 - 1.0, Δx = 0.1) was conducted in low-temperature plasma of hydrogen-oxygen flame. It was found that ions Ca2+, Ti4+ and Si4+ in the molecule of titanit may be substituted with t ions Y3+, Fe3+ and Sn4+. In this case, the system produces two phases of variable composition with broad regions of homogeneity. There were defined the boundaries of formed phases, crystallographic and electrical parameters of the solid solutions. All solid solutions have a semiconductor conductivity type, whose value is linearly dependent on the temperature and com- position of the sample.

Meteorites Penetration into the Dense Layers of the Earth＇s Atmosphere： Physical Mechanism behind the Explosive Phenomena

This discussion paper is an attempt to consider new ideas about the nature of explosive phenomena of the meteorite bodies in the Earth＇s atmosphere. Authors attract approaches, based on the concepts of physics of combustion, explosion and detonation in order to explain the explosive collapse of the meteorite. Authors believe that the meteorite explosion may be the result of gas-detonation mechanism of overheated meteoric bodies explosive boiling-up （the ＂vapor explosion＂）, accompanied by the formation of a supersonic front of shock wave. The considered hypothesis regarding the role of the ＂vapor explosion＂ in geological disasters can be used to explain the mechanisms of explosive phenomena in Volcanology： （1） With respect to the description of nature of phreatic eruptions; （2） for interpretation of dynamic regularities of the volcano crater opening and the subsequent shock-wave emission of steam-gas ＂fountain＂ to a height of several kilometers with fragments of magma and rocks as a result of the ＂vapor explosion＂ of overheated magma mass under the dome of the volcano.

Synthesis of Nanostructured Erbium Oxides and Investigation of Influence Oxides on the Immune System and of Some Animal Tissues

Nanostructured erbium oxides （Er2O3） with coherent scattering length 26, 31, 62 and 65 nm were obtained using as a precursor of erbium chloride and erbium oleate. The influences of Er203 on the immune system and some animal tissues were carried out. The experiments have been made on white mouse＇s and outbred rats. Complex pharmaco-toxicological research presented erbium oxide nanostructure size of coherent scattering regions 26, 31, 56 and 65 nm showed that when administered orally no acute toxicity, no effect on the immune system of the body, has no effect on blood cells. But, long-term （30 day） intragastric administration shows toxicities on the internal organs of experimental animals, which lead to structural changes and functional impairment due to tissue accumulation of nanoparticles.

Confining Potential and Mass of Elementary Particles

In this paper we consider a model in which the masses of elementary particles are formed and stabilized thanks to confining potential, which is caused by recoil momentum at emission of specific virtual bosons by particle itself. The calculation of this confining potential Ф(R) is carried out. It is shown that Ф(R) may be in the form const or const depending on continuous or discrete nature of the spectrum of emitted bosons.

Self-Excitation of the Earthquakes

Numerous correlations between magnetic and seismic events unambiguously indicate that the magnetic control of the earthquakes is a fundamental phenomenon. It proceeds from the remarkable physics of magneto-plasticity of solids, which implies acceleration of dislocations by microwaves. The motion of dislocations provides release of dangerous elastic energy of the earthquake focus and transforms elastic energy into the safe energy of plastic deformation. Magneto-plasticity seems to be the most important mechanism of the magnetic control because the piezoelectric effect as a suggested mechanism of magnetic control should be excluded (Chelidze et al.). Magnetic control certifies earthquake focus as a receiver of microwaves;on the other side, numerous observations exhibit emission of microwaves generated by earthquake focus, so that it can be considered as a permanent generator of microwaves. The idea of this paper is to offer a mechanism of self-excitation of the focus: self-triggering is suggested to be induced by microwaves generated by earthquake focus itself. The more intensive is the crack formation, the higher is the density of microwaves, which accelerate dislocations and intensify crack formation: it is a feedback breeding, avalanche-like process. Both functions of earthquake focus, to be simultaneously generator and receiver of microwaves, are integrated into the same space and time. It excludes such limitation of the magnetic control as the penetrability of the rocks for microwaves.