Plasma treatment of ores, and ore concentrates is used most often to improve the separation performance of ore minerals and non-metallic gangue, as well as for the “plasma grinding” (softening) of ores to reduce the time of subsequent mechanical grinding and energy costs. Non-equilibrium, low-temperature plasma of dielectric barrier discharge (LTP-DBD), characterized by high pressure (hundreds of Torr), high electron temperatures (electron temperatures can reach several electron volts), and low temperature of the process gas (close to the temperature of dielectric barriers) [1] is considered the most precise, efficient, and safe tool for modifying the composition, structure, and properties of the surfaces of various materials, including geomaterials [2–5]. A DBD occurs in a gas under the action of an alternating voltage applied to the conducting electrodes, provided that at least one electrode is covered with a dielectric layer on the side of the discharge gap. The discharge can be carried out in oxygen or air at atmospheric pressure, room temperature, and natural air humidity, i.e., under normal conditions and without the use of a special plasma gas. For practical applications, the problem of obtaining a diffuse discharge in air at atmospheric pressure is relevant, since in this case the effect of the DBD plasma spreads uniformly over the largest possible area [1,3]. During the our experiments, the mineral samples filled the gap between the active metal electrode and the dielectric barrier and were separated from the electrode by a small air gap. The mineral particles were affected by the following DBD factors: a high-strength pulsed electric field, ionic wind, and low-temperature plasma products in the form of chemically active compounds, such as ozone O₃, and other agents. When conducting experiments on the effect of DBD on the structural and physicochemical properties of minerals, the following rational parameters of pulses initiating a barrier discharge we established in [3]: duration of the leading edge of the pulse 250–300 ns, pulse duration 8µs, voltage on the electrodes in the barrier discharge cell 20 kV, repetition frequency of the pulses initiating the discharge ~15 kHz, time range of plasma minerals treatment was t_treat=10–150 s. The dimensions of the electrodes of the DBD discharge cell significantly exceeded the length of the interelectrode gap, which was 5mm. According to SEM, defects of a regular triangular shape formed on the surface of galena samples due to the removal of microcrystalline fragments due to ponderomotive forces in the region of a strong electric field. On the surface of chalcopyrite, the formation of irregularly shaped defects was observed, and on the surface of sphalerite, microchannels of electrical breakdown formed, bordered by the sinter formation material of oxide microphases. The change in the morphology of the surface of sulfides caused softening, and a significant decrease in the microhardness of minerals as a whole by 20–30%. Short (t_treat=10 s) treatment of pyrrhotite caused a shift in the electrode potential of the mineral to negative values (φ=−60mV, at pH 9.7–12) [4], which predetermines the effect of reducing the sorption activity of pyrrhotite with respect to xanthate, hence its flotation recovery reduction. In [5] rational conditions were determined for t_treat=30–40s) plasma pretreatment, in which the efficiency of pyrite and arsenopyrite separation in monomineral flotation increased considerably: an increase in pyrite recovery was 27% while the yield of arsenopyrite decreased by 10–12%. Thus, the method of plasma-chemical processing of geomaterials with using of DBD has great prospects for practical applications in the processes of selective separation of semiconductor ore minerals (sulfides, oxides). In rock-forming minerals, the following features of changes in surface properties when exposed to DBD were established [3]. With increasing plasma treatment time of the quartz samples t_treat=10–150s, smoothing of surface irregularities and the formation of microdefects of irregular shape (≤3µm) occurred This caused weakening and a monotonous decrease in the microhardness of the mineral from 1420 up to 1320 kgf/mm² in the original and modified at t_treat=150 s states, respectively. The maximum relative change (decrease) in microhardness ∆HVmax was ~7%. The contact angle of wetting the quartz surface with water changed nonmonotonically. As a result of short-term exposure (t_treat=10–30s), the contact angle increased from 44° to 53°, which indicates an increase in the hydrophobicity of the mineral’s surface, while with an increase in t_treat, a gradual decrease in the contact angle was observed to initial values. The possibility of modifying the hydrophobicity of quartz by energy impacts can be used in industrial processes for separating the mineral from impurities and selective (reverse) flotation of ferruginous quartzites.

The production of quality castings requires the use of modern computer programs that serve to simulate foundry processes as a tool for optimizing proposed production technologies. This paper focuses on the analysis of a computer simulation concerning the casting of a brake disc at a Slovak foundry. Notably, this brake disc has experienced issues such as shrinkages and micro shrinkages, which adversely affect the internal quality of the casting. Through this study, we aim to enhance our understanding of these challenges and explore solutions to improve the overall quality of cast components, making the process more efficient and cost-effective. Defects were identified in the ribs located in the upper section of the casting beneath the feeders. To address this issue, a comprehensive computer simulation was conducted, replicating the actual conditions of the casting and solidification process. The results revealed that the initially designed gating system, along with its feeder configuration, was inadequate in preventing the formation of these defects. 

In response, a new feeder layout was proposed, which successfully eliminated the defects based on the simulation outcomes. The input parameters for this simulation were meticulously set to reflect the actual requirements of the foundry closely. To facilitate this process, 3D models of the assemblies were created using SolidWorks CAD software, and filling and solidification simulations were carried out using the NovaFlow & Solid CV 4.6r42 simulation program. This approach ensured a thorough analysis and resolution of the issues at hand.

In technological and analytical practice, in preparative chemistry, halogenide complexes of platinum group metals play an important role. Available information concerning Pd(IV) chloride complexes is limited due to the instability of PdCl₄ [1-3], which exists in an individual state only as dichloride. Chlorination of metallic palladium in molten alkali metal chlorides at high temperatures (630-980 °C) and at elevated chlorine pressures (8-10 atm) allows, according to our data, obtaining palladium in rapidly cooled and solidified salt melts based on CsCl mainly in the tetravalent state in the form of Cs₂PdCl₆. However, in RbCl- and KCl-based solidified melts there are complex compounds both of Pd(II) and of Pd(IV), and in solidified melts containing NaCl and LiCl only divalent palladium is present in the form of M₂PdCl₄ compounds.

The ratio of valence forms (II, IV) of palladium chlorides in salt melts and in solidified fusions at different stages and process regimes can be conveniently and quickly monitored by changing the ratio of intensities of the bands of the groupings [PdCl₆]^2- (O_h): n₁(A_1g) ~ 315, n₂(E_g) 290, n₅(F_2g) ~ 170 cm^-1 and [PdCl₄]^2- (D_4h): n₁(A_1g) ~ 300, n₂(B_1g) ~ 270, n₄(B_2g) ~ 200 cm^-1 of the chloride complexes of M₂[PdCl₆] and M₂[PdCl₄] in the Raman spectra, recorded using a Renishaw U1000 spectrometer [4]. 

The use of low-temperature chlorination of Pd(II) compounds in solidified fusions with alkali and alkaline earth metal chlorides (exposed in liquid chlorine for several days at room temperature and for 10-12 hours at 100 °C) made it possible to obtain known hexachloropalladates(IV): M₂[PdCl₆] with M=Cs, Rb, K and new low-stability compounds Na₂[PdCl₆], Li₂[PdCl₆] and Ba[PdCl₆]. The experimental vibration frequencies are within the ranges of 309-323 - n₁(A_1g), 283-295 - n₂(E_g) and 169-176 cm^-1- n₅(F_2g), with a tendency to increase in a series from Cs₂[PdCl₆] to Li₂[PdCl₆] and to Ba[PdCl₆].

 Pd(IV) chloride complexes with chlorides of other alkaline earth metals did not form under the conditions of this study.

Low-melting molten mixtures of sulfur chlorides with chlorides of other elements are promising for use in power sources and environmentally friendly processes for obtaining noble and rare metals [1]. Sulfur in compounds with chlorine may have different valences. The higher (IV, for chlorides) valence state of sulfur is unstable already at room temperature, at which SCl₄ dissociates into SCl₂ and Cl₂ even in the presence of the strongest oxidizer - liquid chlorine. The higher valence state of sulfur can be stabilized by the inclusion of sulfur in the composition of outer-sphere cations SCl₃⁺ in compounds of the [SCl₃]_k·[M_mCl_n] type, where M = Al, Sb, Zr, Nb, Fe, Au, Ir  and some other [1-3].

In the present work, a search for new chloride complexes was carried out. Sulfur together with the corresponding element (Be, In, Ga, V, Ti, Sn, Ge), red phosphorus or some chlorides (ZnCl₂, PbCl₂, GaCl₃, AlCl₃, HfCl₄) were kept for several days at 18–150 °C in sealed quartz ampoules with anhydrous liquid or gaseous Cl₂ at elevated pressures (up to 60 atm). Under these conditions, the indicated elements were chlorinated. Some of the chlorides formed (SCl₂, GaCl₃, VCl₄, TiCl₄, SnCl₄, and GeCl₄) are highly soluble in liquid chlorine. 

The formation of ionic compounds of the [SCl₃]_k·[M_mCl_n] type, which have low solubility in liquefied chlorine and therefore crystallize from solutions, was recorded by the appearance of characteristic bands of their SCl₃⁺ complex cations and M_mCl_n^k– anions in the Raman spectra of solid samples [4]. They were recorded using a Renishaw U1000 spectrometer microscope (laser power 25 mW, λ = 514.5 nm) directly through the glass walls of sealed reactionary ampoules with liquid Cl₂. 

Several new and known compounds have been synthesized according to the described method, for example [SCl₃]^.[BeCl₃],  [SCl₃]^.[AlCl₄], [SCl₃]^.[GaCl₄], [SCl₃]^.[Ga₂Cl₇], [SCl₃]^.[InCl₄], [SCl₃]^.[Ti₂Cl₉], [SCl₃]₂^.[SnCl₆], [SCl₃]₂^.[HfCl₆], [SCl₃]^.[Hf₂Cl₉], containing the pyramidal group SCl₃⁺ [4]. It was established, in particular, that sulfur chlorides do not form complex compounds with germanium and vanadium tetrachlorides, since the Raman spectra of solutions at room temperature only show bands of chlorides of these metals, sulfur dichloride and chlorine. Accordingly, crystalline deposits were also not observed. 

The spectroscopic characteristics of all synthesized chloride complexes, in which the highest valence state (IV) of sulfur is stabilized as a result of complex formation, have been systematized.