Non-metal Content Research Articles

Изменение состава твердых нестехиометрических соединений методом ионного переноса

The paper presents results of measuring electron and ion transfer numbers of titanium hydride, carbide and nitride. It is shown that these compounds had mixed electron-ionic (anionic) conductivity. The dependences of the ion transfer number on the non-metal content in titanium carbide and nitride were obtained, and the change of the non-metal content under the influence of an electric field was studied. The non-metal atoms in non-stoichiometric titanium carbide and nitride were located in the octahedral voids of the titanium cubic lattice, forming a non-metal sublattice. Non-stoichiometric titanium hydride had a fluorite-type cubic crystal lattice, and the hydrogen atoms were located in the tetrahedral voids of the cubic titanium lattice. In titanium boride, ionic conductivity appeared near compounds of stoichiometric composition. It is shown that the formation of interstitial phases corresponded to the Hegg criterion. Due to the existence of vacancies in the non-metal sublattice, ion transfer was possible under the influence of an electric field, resulting in a chemical composition change of non-stoichiometric compounds. Analysis of the physicochemical properties of non-stoichiometric transition metal compounds was carried out as an opportunity to detect the ionic conductivity of carbides, nitrides and oxides.

Assessment of the Ecotoxicity of Pollution by Potentially Toxic Elements by Biological Indicators of Haplic Chernozem of Southern Russia (Rostov region).

The content of various chemical elements such as metals, metalloids, and nonmetals in the environment is associated with natural and anthropogenic sources. It is necessary to normalize the content of metals, metalloids, and nonmetals as potentially toxic elements (PTE) in the Haplic Chernozem. The soils of the Southern Russia are of high quality and fertility. However, this type of soil, like Haplic Chernozem, is subject to contamination with a wide range of PTE. The aim of the work was to rank metals, metalloids, and nonmetals by ecotoxicity in Haplic Chernozem. To assess the ecotoxicity of chernozem, data for 15 years (2005–2020) were used. Biological indicators used to assess the ecotoxicity of Haplic Chernozem: catalase activity, cellulolytic activity, number of bacteria, Azotobacter spp. abundance, to change of length of radish’s roots. Based on these biological indicators, an integral indicator of the state of Haplic Chernozem was calculated. The ecotoxicity of 23 metals (Cd, Hg, Pb, Cr, Cu, Zn, Ni, Co, Mo, Mn, Ba, Sr, Sn, V, W, Ag, Bi, Ga, Nb, Sc, Tl, Y, Yb), 5 metalloids (B, As, Ge, Sb, Te) and 2 nonmetals (F, Se) as priority pollutants. It is proposed to distinguish three hazard classes of metals, metalloids, and nonmetals to Haplic Chernozem: I class — Te, Ag, Se, Cr, Bi, Ge, Sn, Tl, Hg, Yb, W, Cd; II class — As, Co, Sc, Sb, Cu, Ni, B, Nb, Pb, Ga; III class — Sr, Y, Mo, Zn, V, Ba, Mn, F. It is advisable to use the results of the study for predictive assessment of the impact of metals, metalloids, and nonmetals on the ecological state of the soil during pollution.

Functional design and performance evaluation of a metal handheld detector for land mines detection

This study is a requirement for new detectors that must be capable of effectively detecting land mines of low or non-metal content in the operational area employed within South Africa, for the replacement of the current Midas mine detector. The current system capabilities are no longer feasible to detect the latest mines since warfare has changed and with relatively no logistical support (spares, manuals, qualified personnel and workshop). The research focused more on the improvement in the systems’ capabilities of the detector in order to effectively detect the various types of mines found in the target area which were buried at the maximum operational depth, in all soil conditions with no loss of sensitivity and accuracy. The detector is also expected to accurately locate the position of a mine buried under the ground. The functional design and specification led to the acquisition of a low power and highly portable mine detector capable of delivering 24 hours continuous throughput before recharge. The performances of these upgrades were compared with the performance of the original Midas detector as well as the Guartel MD8 detector currently used by The South African Army Engineer Council (SAEC). The findings show significant improvement in the use of the new detectors. This suggests that the Midas handheld detector can be upgraded to meet the operational requirements regarding the detection of mines with a minimum metal content.

Characteristics of Plasma-Electrolytic Oxide Coatings Formed on Aluminum and Titanium in Electrolytes with Siloxane Acrylate and Particles of Vanadium, Boron, and Aluminum Oxides

It is shown that aqueous suspension-emulsion electrolytes containing sodium silicate, siloxane-acrylate emulsion, and dispersed particles of oxides are promising for direct synthesis by the plasma-electrolytic oxidation method of coatings with multicomponent composition on titanium and aluminum. The formation processes, composition, and structure of the coatings were studied in electrolytes with 1–4-μm particles of V2O5, B2O3, or Al2O3. The average content of metals and nonmetals of dispersed particles in the surface part of the coatings is ~1–2 at %. The coatings have a developed surface morphology and contain in the surface part up to 50–73 at % carbon.

Characterization of Waste Printed Circuit Boards Nonmetals and its Reutilization as Reinforcing Filler in Unsaturated Polyester Resin

Waste printed circuit boards (WPCB) nonmetals were firstly recycled as reinforcing filler in a kind of novel room temperature cured unsaturated polyester (UPE) composites. The compositions and characteristics of WPCB nonmetals were detailly analyzed by SEM, FTIR, TGA and Py-GCMS, and the effects of the content of WPCB nonmetals on the mechanical performance and thermal behaviors of UPE composites were also systematically studied. Results suggested that UPE composites incorporated with WPCB nonmetals at appropriate content showed superior tensile strength, flexural strength and heat distortion temperature than UPE matrix. Based on the analysis of thermal degradation kinetic, the thermal stability of UPE composites were significantly enhanced by the incorporation of WPCB nonmetals. The highlight of this work lies in the fact that high-valued utilization of WPCB nonmetals is realized in room temperature cured UPE matrix, which may not only achieve favorable economic and social benefits, but also open up new opportunities for the preparation of high performance plastic composites.

A Hydrometallurgical Approach to Recover Zinc and Manganese from Spent Zn-C Batteries

This study addresses the recovery of recovery of zinc (Zn) and manganese (Mn) from spent dry cell (Zn-C battery) batteries using a hydrometallurgical approach. Every year, a significant number of Zn-C dry cell batteries are consumed and disposed worldwide. Zn-C dry cell batteries constitute more than 60% of Zn and Mn together. Higher amount of Zn and Mn present in Zn-C dry cells shows an industrial interest in recycling and recovering Zn and Mn. In this study the recovery of Zn and Mn from spent dry cells was investigated through an energy efficient hydrometallurgical route. Zn-C batteries were manually dismantled to collect the battery paste. Neutral leaching was carried out to remove potassium and non-metal contents. The battery powder was leached in sulfuric acid medium with glucose as reducing agent. The experiments were conducted according to ‘24 full factorial design’. The purpose of the design was to identify the most effective and optimum condition for Zn and Mn recovery from spent Zn-C batteries. Using the optimum operating condition, up to 86.54 % of Mn and 82.19% of Zn were recovered from the original battery powder.

Fractal features of carbon-nickel composite thin films.

This work analyses the three-dimensional (3-D) surface texture of carbon-nickel (C-Ni) films grown by radio frequency (RF) magnetron co-sputtering on glass substrates. The C-Ni thin films were deposited under different deposition times, from 50 to 600s, at room temperature. Atomic force microscopy was employed to characterize the 3-D surface texture data in connection with the statistical, and fractal analyses. It has been found that up to 180s the sputtering occurs in more metal content mode and in greater than 180s it occurs in more non-metal content mode. This behavior demonstrated a strong link between the structural and morphological properties of C-Ni composite films and facilitates a deeper understanding of structure/property relationships and surface defects in prepared samples. Furthermore, these findings can be applied to research on the mechanisms to prepare and control high-quality C-Ni films.

Determination of metal, non-metal and heavy metal contents of some tropical fruits growing in Indonesia

The importance of the current study was to determine the mineral and heavy metal contents of several tropical fruits provided from Indonesia. Mineral contents of some tropical fruits were determined by inductively coupled plasma-atomic emission spectrometry. As macro element, Ca contents of fruits were found between 167 mg/kg (Pir) and 1,051 mg/kg (Jambu). In addition, K contents of fruits ranged from 5,803 mg/kg (Manggis) to 17,659 mg/kg (Dragori). P contents ranged from 491 mg/kg (Sukun) to 3158 mg/kg (Dragori) (P<0.05). As micro element, Fe content varied between 24.7 mg/kg (Pir) and 54.1 mg/kg (Dragori). In addition, while Mn contents of fruits change between 2.3 mg/kg (Sukun) and 33.2 mg/kg (Starfruit), Zn content varied from 2.9 mg/kg (Sukun) to 37.5 mg/kg (Dragori) (P<0.05). As heavy metal, Cd, Cr, Mo and Ni contents of fruits were found at low levels.

Assessment of eco-hazard of copper-nickel ore mining and processing waste

The authors examine oxidation of sulfide minerals in mine waste and the associated ecological problems. The highest environmental hazard is produced by fine-dispersed mill tailings, especially where sulfide content is comparable with nonmetal content of low-chemical activity. In terms of some production waste accumulations in Murmansk Region, it is shown that the eco-hazard source can be not only fine but also coarse particle waste (Allarechensky mine waste) and ore concentration waste with low sulfide content but highly chemical-active nonmetals (Pechenga ore field).

The Effect of Deposition Rate on Morphology and Structural Properties of Carbon-Nickel Composite Films

Carbon-nickel films were grown by radio frequency magnetron cosputtering on glass substrates. The films were deposited under different deposition times, from 50 to 600 sec, at room temperature. We noticed that up to 180 sec the sputtering occurs in more metal content mode and in greater than 180 sec it occurs in more nonmetal content mode. It is shown that the structural and morphological properties of carbon-nickel films were strongly influenced by this behavior.

Effect of Draw Blank Velocity on Steel Fluid Flow Field in Blank Continuous Caster Crystallizer

As the heart of continuous caster, crystallizer is the cradle of most surface deficiencies and inside quality problems in steel blank. Steel blank surface quality, nonmetal impurity content and relevant distribution rely on the steel fluid solidification behavior namely steel fluid flow field distribution on great extent. For the high temperature steel fluid has big kinetic energy, so, the immixture dregs, solidification heat conduction, temperature field distribution in crystallizer, solidification blank shell thickness distribution and continuous caster blank quality were influenced by steel fluid flow. The numerical simulation analysis on flow field and temperature field in crystallizer were conducted in this paper. Three dimensions turbulent flow model was adopted to computate flow field. The heat conduction was ignored on draw blank direction in temperature field. The conjugate heat conduction model of ANSYS CFX was adopted to analyze temperature field, which can consider heat conduction in solid layer and convection heat conduction between solid shell face and fluid simultaneity. The draw blank velocity was found by setting crystallizer water gap insertion depth and crystallizer water gap angle, which can obtain reasonable flow field in blank crystallizer.

(Zr,Ti)CN coatings as potential candidates for biomedical applications

(Zr,Ti)CN hard coatings, deposited by DC magnetron sputtering on Ti6Al4V alloy and Si substrates, were investigated as possible candidates to be used as protective layers for medical implants. Two coating types, with different non-metal/metal ratios, were prepared. The films were analyzed for elemental and phase composition, crystallographic structure, mechanical properties, corrosion behavior, surface wettability and cell viability. The coatings were found to have composite structures, in which a (Zr,Ti)CN crystalline phase coexists with an amorphous a-C(N) one. Film thickness and hardness in the ranges 1.8–2.1μm and 25–29GPa, respectively, were measured. The coated samples exhibited an improved corrosion resistance as compared with the Ti6Al4V alloy. Both coating types were found to be hydrophobic, the contact angles being higher than 100°. Cell viability measurements proved that the osteosarcoma cells are adherent to the coating surface, the highest viability (90.5%) after one week incubation being found for the film with high non-metal content.

Study of (Zr,Ti)CN, (Zr,Hf)CN and (Zr,Nb)CN films prepared by reactive magnetron sputtering

(Zr,Ti)CN, (Zr,Hf)CN and (Zr,Nb)CN coatings, in which Ti, Hf and Nb were added to ZrCN base compound, have been prepared by reactive magnetron sputtering. The coatings, with two different non-metal/metal ratios, were comparatively investigated in terms of elemental and phase composition, texture, surface morphology, hardness and friction performance. It has been shown that the films exhibit nanocomposite structures, consisting of a mixture of crystalline metal carbonitride and amorphous carbon. As compared with ternary ZrCN coatings, the quaternary coatings were found to exhibit superior mechanical and friction characteristics. In general, the films with higher non-metal content revealed finer morphologies, higher hardness and lower friction coefficient. Depending on the coating type and non-metal/metal ratio, the hardness values ranged from about 21 to 29 GPa, being higher than those of ZrCN reference films. The coefficients of friction varied from 0.2 to 0.5, the lowest values being obtained for the coatings with the highest non-metal content.

Evaluation of sunflower metabolism from zinc and selenium addition to the culture: A comparative metallomic study

This work reports the evaluation of sunflower growth under different irrigation conditions and explores a metallomic approach for evaluation of metal and non-metal content in different plant tissues. Sunflowers were cultivated in the presence of zinc (acetate salt) and selenium (as sodium selenite) by adding ca. 230 or 430, and ca. 190 or 350 mg, respectively, during the cultivation period. These plants were compared with controls in terms of some monitored ions ( 24Mg +, 31P 16O +, 32S 16O +, 56Fe +, 64Zn +, 80Se +) using ICP-MS. The results highlighted no apparent problem during the development period for those plants cultivated in the presence of zinc. However, higher selenium levels are present mainly in leaves, which can be due to its incorporation in synthesized amino acids such as selenocysteine and selenomethionine.

Performance and thermal behavior of wood plastic composite produced by nonmetals of pulverized waste printed circuit boards

A new kind of wood plastic composite (WPC) was produced by compounding nonmetals from waste printed circuit boards (PCBs), recycled high-density polyethylene (HDPE), wood flour and other additives. The blended granules were then extruded to profile WPC products by a conical counter-rotating twin-screw extruder. The results showed that the addition of nonmetals in WPC improved the flexural strength and tensile strength and reduced screw withdrawal strength. When the added content of nonmetals was 40%, the flexural strength of WPC was 23.4 MPa, tensile strength was 9.6 MPa, impact strength was 3.03 J/m 2 and screw withdrawal strength was 1755 N. Dimensional stability and fourier transform infrared spectroscopy (FTIR) of WPC panels were also investigated. Furthermore, thermogravimetric analysis showed that thermal degradation of WPC mainly included two steps. The first step was the decomposition of wood flour and nonmetals from 260 to 380 °C, and the second step was the decomposition of HDPE from 440 to 500 °C. The performance and thermal behavior of WPC produced by nonmetals from PCBs achieves the standard of WPC. It offers a novel method to treat nonmetals from PCBs.

Phenolic Molding Compound Filled with Nonmetals of Waste PCBs

Nonmetals reclaimed from waste phenolic cellulose paper printed circuit boards (PCBs) are used to replace wood flour in the production of phenolic molding compound (PMC). The results indicate that filling of nonmetals in PMC improves the charpy notched impact strength and heat deflection temperature (HDT) and reduces flexural strength and rasching fluidity. Rasching fluidity decreases dramatically with the increase of the content of nonmetals. To ensure sufficient properties of PMC, the optimal added content of nonmetals is 20 wt %, which results in a flexural strength of 70 MPa, a charpy notched impact strength of 2.4 KJ/m2, a HDT of 168 degrees C, a dielectric strength of 3.9 MV/m, and a rasching fluidity of 103 mm, all of which meet the national standard data. When the added content of nonmetals is 20%, the charpy notched impact strength, HDT, and rasching fluidity of PMC decrease, and the flexural and dielectric strengths decrease at first and then increase with decreasing particle sizes. All the results indicate that making PMC with nonmetals of waste PCBs can resolve environmental pollution, reuse nonmetals in different fields, and provide a new method for resource utilization of nonmetals from waste PCBs.

Thermo-chemical properties and electrical resistivity of Zr-based arsenide chalcogenides

abstractTernary phases in the systems Zr–As–Se and Zr–As–Te were studied using single crystals of ZrAs1.40(1)Se0.50(1) and ZrAs1.60(2)Te0.40(1) (PbFCl-type of structure, space group P4/nmm) as well as ZrAs0.70(1)Se1.30(1) and ZrAs0.75(1)Te1.25(1) (NbPS-type of structure, space group Immm). The characterization covers chemical compositions, crystal structures, homogeneity ranges and electrical resistivities. At 1223 K, the Te-containing phases can be described with the general formula ZrAsxTe2–x, with 1.53(1)≤x≤1.65(1) (As-rich) and 0.58(1)≤x≤0.75(1) (Te-rich). Both phases are located directly on the tie-line between ZrAs2 and ZrTe2, with no indication for any deviation. Similar is true for the Se-rich phase ZrAsx–ySe2–x with 0.70(1)≤x≤0.75(1). However, the compositional range of the respective As-rich phase ZrAsx–ySe2–x (0.03(1)≤y≤0.10(1); 1.42(1)≤x≤1.70(1)) is not located on the tie-line ZrAs2–ZrSe2, and exhibits a triangular region of existence with intrinsic deviation of the composition towards lower non-metal contents. Except for ZrAs0.75Se1.25, from the homogeneity range of the Se-rich phase, all compounds under investigation show metallic characteristics of electrical resistivity at temperatures >20 K. Related uranium and thorium arsenide selenides display a typical magnetic field-independent rise of the resistivity towards lower temperatures, which has been explained by a non-magnetic Kondo effect. However, a similar observation has been made for ZrAs1.40Se0.50, which, among the Zr-based arsenide chalcogenides, is the only system with a large concentration of intrinsic defects in the anionic substructure.

Formation of IIAB iron meteorites

Group IIAB is the third largest group of iron meteorites and the second largest group that formed by fractional crystallization; many of these irons formed from the P-rich portion of a magma consisting of two-immiscible liquids. We report neutron-activation data for 78 IIAB irons. These confirm earlier studies showing that the group has the largest known range in Ir concentrations (a factor of 4000) and that slopes are steeply negative on plots of Ir vs. Au or As (or Ni). High negative slopes imply relatively high distribution coefficients for Ir, Au, and As (but, with rare exceptions, remaining less than unity for the latter). IIAB appears to have had the highest S contents of any magmatic group of iron meteorites, consistent with its high contents of other volatile siderophiles, particularly Ga and Ge. Large fractions of trapped melt were present in the IIAB irons with the highest Au and As and lowest Ir contents. As a result, when these irons crystallized, the D Au and D As values can, with moderate accuracy, be estimated to have been roughly 0.53 and 0.46, respectively. These low values imply that the initial nonmetal (S + P) content of the magma was much lower than 170 mg/g, as estimated in earlier studies; our estimate is 75 mg/g. Our results are consistent with an initial P/S ratio of 0.25, similar to the ratio estimated for other magmatic groups. There is little doubt that incompatible S-rich and P-rich metallic liquids were involved during the formation of group IIAB. After 20% crystallization of our assumed starting composition the two-liquid boundary is encountered (at 72 mg/g S and 18 mg/g P). Initially the volume of S-rich liquid is very small, but continued crystallization increased the volume of this phase and decreased its P/S ratio while increasing this ratio in the P-rich liquid. Most crystallization of the IIAB magma would have occurred in the lower, P-rich portion of the core. However, metal was still a liquidus phase at the top of the core and, because both the immiscible liquids would have convected, they may have approached equilibrium throughout the very limited crystallization of the magma recorded in group IIAB. All IIAB irons contain trapped melt, and this melt will have had very different compositions depending on whether the liquid is S-rich (at the outer solid/liquid interface) or P-rich (at the inner interface). The P/S ratio in the melt trapped in the Santa Luzia iron is about 0.6 g/g, consistent with our modeling of Ir–Au and Ir–As trends implying that Santa Luzia formed in the lower, P-rich portion of the core after about 48% crystallization of the magma. Because the liquids were in equilibrium, the point at which immiscibility first occurred is not recorded by a dramatic change in the trends on element–Au diagrams; the main compositional effect is recorded in the P/S ratio of the trapped melt. The high-Au (>0.8 μg/g) irons for which large sections are available all contain skeletal schreibersite implying a relatively high (>0.3 g/g) P/S ratio; none of these irons could have crystallized from the S-rich upper layer of the core.

Multi-component co-condensation model of Ti-based boride/silicide nanoparticle growth in induction thermal plasmas

Numerical analysis is conducted for the titanium-based boride and silicide nanoparticle synthesis using an induction thermal plasma including the material evaporation process and the nanoparticle growth process with nucleation and co-condensation. Both systems present the nano-scaled particle size distributions. Ti–B system shows the smaller particle diameter, sharper distribution, larger particle number density, and wider range of the composition than Ti–Si system. Ti–Si system provides a narrower range of the silicon content due to the simultaneous co-condensation of titanium and silicon. Finally the correlation between the particle size and the nonmetal content of the synthesized nanoparticles is presented on a chart.

Sputtered Fe 1− x(N 1− yC y) x films obtained in various (Ar–N 2–CH 4) reactive plasmas

The Fe 1− x (N 1− y C y ) x iron carbonitrides commonly encountered with high non-metal content are the ε ( x = 0.25–0.33) and ζ ( x = 0.33–0.36) phases whose structures derive from the ones existing in the binary Fe–N system by substituting N by C. As it is possible to synthesize cubic γ″ and γ‴ iron nitrides with an atomic nitrogen content x close to 0.5, we study here the possibility to substitute N by C to obtain carbonitrides close to an equiatomic non-metal content. Fe 1− x (N 1− y C y ) x films were deposited on copper substrates using a triode sputtering magnetron mode with an iron target in a variable reactive Ar–N 2 and/or –CH 4 mixture. Energy Dispersive X-ray Analysis was used to determine their composition. The as-sputtered states were identified by X-Ray Diffraction. The target being magnetic, we propose a particular geometry allowing its sputtering. In a pure (Ar–N 2) reactive plasma ( y = 0), the atomic nitrogen content x in the films increases linearly from 0 to 0.51 with the N 2 flowing rate and then stays constant. The successive nitrides, ε-Fe 3N, ζ-Fe 2N and a mixture of γ″ and γ‴ can be identified. However, some diffraction peaks remain not indexed using the previous phases. In a pure (Ar–CH 4) reactive plasma ( y = 1), the atomic carbon content x in the films increases rapidly and linearly from 0 to 0.62 as a function of the CH 4 flowing rate while structure changes from α-Fe to χ-Fe 5C 2 via ε-Fe 3C and then to an amorphous compound. In a variable (Ar–N 2–CH 4) reactive plasma, Fe 1− x (N 1− y C y ) x ternary films keeping x close to 0.5 with various y values within the range 0–0.46 are obtained. The crystalline carbonitrides detected by X-Ray Diffraction evolves from a γ″/γ‴ mixture for y = 0 to ζ for y = 0.41–0.46 passing through a ζ/γ‴ mixture for y = 0.33.