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The electrochemical behavior of manganese silicide-germanides with different ratios of germanium and silicon is studied using the methods of voltammetry and impedance spectroscopy in 0.5 M aqueous sodium sulfate solution. It is shown that the oxidation stability of materials decreases with an increase in the ratio of germanium, which, unlike silicon, is incapable of forming a layer of stable oxides on the material surface. [ABSTRACT FROM AUTHOR]

High‐strength foamed ceramics were synthesized employing silicon‐manganese slag (SM) and fluorgypsum (FG) as raw materials, with SiC serving as the foaming agent. Investigations into the influence of firing temperature and FG content on the phase structure, microstructure, and physical properties of foam ceramics were conducted. Characterization of the samples was performed through X‐ray diffraction and scanning electron microscopy. Results indicate that an increase in FG content lowers the matrix melting point, promotes crystal growth, enhances compressive strength, and forms a uniform pore structure. At an FG content of 11%, ceramics prepared at a firing temperature of 1130°C exhibit a density of 0.56 g/cm3, porosity of 78.45%, and compressive strength of 3.05 MPa. This study explores the use of FG as a cost‐effective alternative to borax, demonstrating a sustainable approach for foam ceramics preparation using silicomanganese slag and FG synergy. [ABSTRACT FROM AUTHOR]

To receive a high-quality welding structure of high-strength S700MC steel for applications in the automotive industry, newly developed electrode wires with increased silicon and manganese content were used. The strength and structural tests of the obtained joints were performed. In the weld, we identified the beneficial oxides strengthening the joint structure and unfavorable MnS inclusions. The non-metallic inclusions were formed inside the weld. Their arrangement, morphology, and chemical composition is described. A view on the high-temperature mechanisms of the formations included during the welding process with new electrode wires is presented. It was found that the dominant mechanism of the inclusion formation and the temperature of the welding process impact the content and varied morphology of inclusions, thus determining the exploitation time of the welded joints obtained. The obtained MAG joints made S700MC steel, due to the formation mainly of oxide inclusions and a relatively small amount of MnS phase, were characterized by a high value of yield and tensile strength, which makes them a promising solution for the automotive industry, especially against the background of connections from the discussed steel grade presented in the literature. [ABSTRACT FROM AUTHOR]

Investigation of the possibility of obtaining a complex master alloy used in the deoxidation of steel, smelted from substandard manganese-containing materials, briquettes, and high-ash coals in ore-thermal electric furnaces. Thermodynamic modeling was carried out using the HSC Chemistry software package to determine the optimal process parameters using a second-order rotatable plan (Box-Hunter plan). Thermodynamic modeling improves the understanding of physical and chemical processes, allows making predictions about the behavior of the system under various conditions, optimizing processes and saving time and resources necessary for experiments. Electric smelting of the briquette was carried out with coal and quartzite (to adjust the chemical composition and neutralize residual carbon) in an ore-thermal electric furnace with a power of up to 150 kV*A. The influence of temperature on the equilibrium distribution of silicon, manganese, and aluminum in the «briquette-coal-quartzite» system, the degree of transition of silicon and manganese into a complex ligature and the content of these metals in the alloy are determined by the method of thermodynamic modeling. As a result of experiments on ore-thermal electric smelting of a briquette with high-ash coal, a complex ligature was obtained with an average content of 45.92–53.11% silicon, 27.72–34.81% manganese and 5.60–6.91% aluminum. [ABSTRACT FROM AUTHOR]

Herein, we report the production of silicomanganese slag-reinforced porous SiC ceramic membrane supports with high alkali corrosion resistance through low-temperature sintering. The effects of the sintering temperature and particle size of the silicomanganese slag (SiMn-slag) on the properties of the membrane supports were studied. The optimal membrane support was obtained at 1150 °C with 20 μm SiMn-slag, which exhibited an open porosity of 41.03%, pore size of 3.15 μm, ultra-high pure water permeability of 120074.60 L·m−2·h−1·bar−1 and high bending strength of 43.18 ± 0.70 MPa. In addition to the excellent acid corrosion resistance, the prepared membrane support displayed high alkali corrosion resistance due to the neck connections that formed, comprising alkali resistant mullite, anorthite, and bustamite. This work is of great significance in guiding the production of high-performance SiC membranes at a low cost and offers a possible route for utilising solid waste as a value-added separation material. [ABSTRACT FROM AUTHOR]

In order to solve the problem of high accumulation of silicon-manganese slag, this paper proposes a method to prepare foam ceramics with high porosity using silicon-manganese slag as raw material. Two types of silicon-manganese slag were obtained from different regions of Ningxia, China, and used to prepare foam ceramics. This was done with the help of one-step sintering method by adding SiC as a foaming agent and borax as a flux. The effects of chemical composition and crystal phase difference of silicomanganese slag on the physical properties, phase and micromorphology of foam ceramics were investigated. By adjusting the firing temperature and foaming agent content, the optimal process for the preparation of foam ceramics by two kinds of silicomanganese slag was determined. The phase and microstructure of the samples were characterized by X-ray diffractometer (XRD) and scanning electron microscope (SEM), and physical analysis was carried out. The results show that when the sintering temperature of the Huiyi silica manganese slag (HYSM) sample is 1100 °C, the bulk density reaches the minimum value of 0.41 g/cm3, while the porosity and compressive strength are 86.26 % and 0.95 MPa, respectively. On the other hand, when the sintering temperature of the Tianyuan silica manganese slag (TYSM) sample is 1110 °C, the packing density reaches a value of at least 0.51 g/cm3, while the porosity and compressive strength are 80.07 % and 2.09 MPa, respectively. The XRD and SEM results show that the crystalline phase of the HYSM sample is mainly magnesium feldspar, while that of the TYSM sample is mainly diopside. In this study, two kinds of silicon manganese slag with different physical and chemical properties were used to prepare foam ceramics with high porosity, and a theoretical basis for the large-scale use of silicon manganese slag in foam ceramics was presented. [ABSTRACT FROM AUTHOR]

This study investigates the deformation characteristics of SiO2–MnO–(CaO–Al2O3)‐type inclusions in silicon manganese deoxidized steel from continuous casting to rolling. The results reveal that the inclusions contain 60–80% SiO2, 10–35% MnO, and a combined CaO and Al2O3 content of <20%. SiO2 precipitates inside the inclusions during the continuous casting and rolling processes, which results in the formation of pure SiO2/SiO2–MnO–(CaO–Al2O3) dual‐phase inclusions in the remaining components owing to the increase in the MnO content to 15–40%. According to the experimental results of melting rate measurement and thermodynamic calculation using FactSage8.1, the SiO2–MnO–(CaO–Al2O3) phase has a high proportion of liquid components at 1100–1360 °C and exhibits good deformation properties during the breaking down and rolling processes. When the total content of CaO, Al2O3, and MgO in the SiO2–CaO–Al2O3–MgO–MnO inclusions reaches 30–50%, SiO2 precipitation is inhibited during the continuous casting to rolling process. Through the addition of metal manganese and carbon powder during the pre‐deoxidation process, followed by alloying with ferrosilicon and metal manganese, and then the addition of acidic synthetic slag for slag formation, the proportion of SiO2/SiO2–MnO–(CaO–Al2O3) dual‐phase inclusions in the casting billet is increased from 12% to >60%. [ABSTRACT FROM AUTHOR]

Artificial aggregate (AF), i.e., silico manganese (SiMn) slag aggregate, is a byproduct of ferromanganese and silico manganese alloy production. The utilization of industrial waste and industrial byproducts in construction has increased the aim of conserving natural resources to nurture a pollution-free environment. The current study examines the performance of the use of artificial aggregate (AF) and partial replacement of cement with fly ash (FA). The properties of fresh concrete, as well as the compressive and flexural strength and split tensile strength of concrete were evaluated. Seven mix proportions were prepared for M30-grade concrete. The first was a control mix (with 0% AF and FA), three other mixes contained varying amounts of AF (20%, 40%, and 60%) as a partial replacement of CA with AF. The average compressive strength of the control SCC was found to be 32.87 MPa (megapascals) at the age of 28 days, and after replacing 20% natural aggregate with artificial aggregate, the compressive strength increased by 8.27%, whereas for 40% and 60% replacement, it decreased by 4.46% and 12.55%, respectively. Further investigation was performed on the optimum value obtained by replacing 20% of CA with AF. At this percentage, cement was replaced by FA at (15%, 25%, and 35%) where at 15%, the average compressive strength increased by 7.41%, whereas for 25% and 35% replacement, it decreased by 7.47% and 17.19%, respectively. For SCAF20 and SCF15, all strengths were at maximum due to the increase in its density. The findings show that the development of advanced construction materials is environmentally sustainable. [ABSTRACT FROM AUTHOR]

High-strength steels (HSS) appear as a good alternative to common steels to reduce vehicle weight, thus reducing fuel consumption. Despite the excellent mechanical behavior towards its lower weight, its application in industry is still limited, as manufacturing such materials suffers from limitations, especially regarding formability. The literature shows springback to be the most common problem. Among the parameters that can be studied to minimize this problem, the temperature appears, according to the literature, to be one of the most influential parameters in minimizing springback. However, the consequence of the temperature increase on the forming limits of materials is not completely understood. This study proposes to determine the consequences of the use of the temperature rise technique in the forming limits of high-strength steels. Two different steels were studied (HSLA 350/440 and DP 350/600). To evaluate the formability, the Nakazima method was used (practical). Finite element models were made which describe the material as well as Nakazima experimental behavior. To predict the forming limit strains via the numerical method, the thickness gradient criterion was applied. The practical and computational results were compared to validate the finite element model. Four different temperature ranges were analyzed. In general, it was found that 400 °C has a negative impact on the forming limits of both steels. This negative effect was found to be due to the alloying elements, such as silicon and manganese, present in the alloy. These alloying elements take part in the increase and decrease in resistance coefficient at the elevated temperature. For HSLA 350/440 steel, the forming limit strain decreased with an increase in temperature up to 600 °C and then increased at 800 °C; whereas for DP 350/600 steel, the forming limit strain decreased till 400 °C and then increased for 600 °C and 800 °C. Another factor which might have contributed to the behavior of the DP steel is the interaction of hard martensite with soft ferrite phase. [ABSTRACT FROM AUTHOR]

In No. 3 hot strip mill at JFE Steel East JapanWorks (Chiba), mild steels are produced by the endless rolling process, in which rough rolled bars are joined and rolled continuously in the finishing mill. However, this process is not applied to high tensile strength steels because the alloy elements contained in those steels, such as silicon and manganese, form an oxide layer at the joining interface, disrupting the joining process. In laboratory joining tests, heating the joining surface until it melted resulted in discharge of the oxide layer from the interface, and steels that form oxide with a low melting temperature were successfully joined. A FEM flow analysis revealed that the viscosity of the oxide is the most important parameter for discharge. The low melting temperature of the oxide leads to low viscosity, resulting in the discharge of the oxide layer. [ABSTRACT FROM AUTHOR]

Results of studies for preparing complex Fe–Si–Mn–Al master alloy are presented. High-silicon lean manganese ores of the West Kamys ore deposit (18–30% Mn and 35–45% SiO2) and high-ash coal of the Saryadyr deposit (Kazakhstan) with an ash content of 45–55% are used as charge materials. Technological studies are conducted in an ore-thermal electric furnace with a capacity of 250 kVA. An experimental batch of master alloy with an average chemical composition is obtained, %: Mn — 20; Si — 42; Al — 16; P — 0.03; Fe balance. Dependences of aluminum, silicon and manganese content in final alloy on ratios Mnox + Feox + SiO2 + Al2O3)/Cso and Mnox/(Mnox + Feox + SiO2 + Al2O3) in an initial charge are revealed. The fundamental possibility and expediency of obtaining an aluminum silicon manganese master alloy of a new composition by a slag-free method with integrated use of all useful components of lean manganese ore and high-ash coal is demonstrated. An X-ray diffraction pattern of prototypes indicates that alloy phase composition is presented in the form of intermetallics — MnSi, Mn15Si26, Al2Fe3Si4, Al5Fe2, FeSi, and structurally free silicon. The resulting master alloys of selected composition are not subject to self-dispersal reactions. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to reduce the manufacturing cost of foamed ceramics and expand the application scope of industrial solid waste, in this study, a new type of environment-friendly foamed ceramics was prepared using direct high-temperature foaming with waste silicomanganese slag (SMS) and fly ash (FA) as raw materials and silicon carbide (SiC) as a foaming agent. The influence of SMS content, SiC content, and sintering temperature on the characteristics and microstructure of the specimen were explored. More concretely, the compressive strength, pore morphology, bulk density, and crystalline composition of the foamed ceramics were discussed. The foaming mechanism was also further analyzed. The results showed that including 20% SMS significantly reduced the melt's viscosity and stimulated bubble expansion. This, in turn, facilitated the creation of a porous structure. Moreover, it was noted that samples containing 20% SMS exhibited an anorthite phase when sintered at 1110 °C, resulting in enhanced compressive strength. The bulk density and compressive strength of the foamed ceramics decreased with an increase in the sintering temperature and SiC content. This trend was primarily attributed to the higher total porosity and the insufficient support of the pore wall to the matrix. The best all-around performance was achieved with 20 wt% SMS, 80 wt% FA as raw material, SiC addition of 1.0 wt%, and a sintering temperature of 1100 °C. Under these conditions, the compressive strength, bulk density, and total porosity of the foamed ceramics were 8.09 MPa, 0.57 g/cm3, and 71.04%, respectively. Taken together, the outstanding porous structure and mechanical properties of this foamed ceramic make it suitable for use as insulation or for building partition materials. [ABSTRACT FROM AUTHOR]

In order to advance the utilization rate of multi-source solid wastes in the Ningxia region of China, 16 groups of pavement base mixtures were designed with cement and fly ash (FA) as binders, steel slag (SS), silicon manganese slag (SMS), and recycled crushed stone (RCS) as composite aggregates. The evolution laws of mechanical and frost resistance properties of the mixture were investigated by unconfined compressive strength (UCS), indirect tensile strength (ITS), freeze–thaw (FT), and ultrasonic detection tests. Then, the strength formation mechanisms were revealed by microscopic characterization technology. The mathematical models between UCS-ITS, UCS-ultrasonic amplitude, FT cycles-UCS damage, and frost resistance coefficient-relative dynamic elastic modulus Er were established. The results show that cement content and curing age exhibited a positive effect on the mechanical strength and frost resistance of the mixture. When the replacement rate of SS was 60%, the mechanical strength and frost resistance were preferable. The R2 of the strength relationship models constructed was greater than 0.9, indicating high fitting accuracy. With the extension of the curing age, the cementitious products such as C-S-H (hydrated calcium silicate) and AFt (ettringite) developed entirely, and they were interlocked and cemented with each other, resulting in the micro-morphology developed from the three-dimensional network structure to the dense system. The macroscopic behavior incarnated that the mechanical strength and frost resistance of the mixture were significantly enhanced. [ABSTRACT FROM AUTHOR]

Medium manganese steel has excellent comprehensive properties due to the TRIP effect of retained austenite, but its welding performance is unsatisfactory for its high alloy content. This study obtained retained austenite in low-carbon low-alloy steel with low contents of silicon and manganese elements through intercritical heat treatment. The influence of intercritical quenching temperature on the content and characteristics of the retained austenite, as well as the functional mechanism of the retained austenite during low-temperature impact, was studied. The results showed that the content of the retained austenite increased from 12% to 17%, and its distribution extended from grain boundaries to martensite lath boundaries, with increasing intercritical quenching temperature. The retained austenite on the grain boundaries was in blocks, and that on the martensitic lath boundaries formed slender domains. The stability of the retained austenite was achieved through the enrichment of C and Mn during intercritical heat treatment. The contribution of retained austenite to low-temperature mechanical properties was closely related to its stability. The retained austenite with poor stability underwent martensite transformation at low temperatures, and the high-carbon martensite was a brittle phase that became the nucleation site of cracks or the path of crack growth during impact. Stable retained austenite passivated crack tips and hindered crack propagation during impacts, which improved the impact performance of the steel. [ABSTRACT FROM AUTHOR]

Cellular glass non-conventionally prepared from post-consumer drinking glass was made, silicon nitride (Si3N4) and manganese dioxide (MnO2) contributing to form the porous structure. The correlation between the physical-morphological properties (low denseness, high porousness, structural homogeneousness) of the expanded material and its strength features (high compression resistance) played an essential role. An optimal weight ratio between the two pore-forming additives was found at the value 1.0. The temperature of the sintering-expanding process was relatively reduced (823℃) and the warming rate reached very high values (27.7℃/min) due to the energy efficiency of the own preponderantly direct microwave warming method. The main features of the optimal cellular glass specimen were: denseness of 0.59 g·cm-3, heat conduction of 0.097 W·m-1 ·K-1, compression resistance of 6.6 MPa, and pore size between 0.1-0.4 mm. [ABSTRACT FROM AUTHOR]

Non-uniform shell growth commonly caused by the peritectic transformation in low carbon and low alloy steels has been directly correlated with mold thermal maps using a mold immersion test into a molten steel alloy. Mold thermal maps were obtained by performing real-time temperature measurements with optical fibers embedded 1 mm from the mold working surface. Shell growth measurements were obtained by 3D optical scanning of the recovered steel shell following immersion testing. The effects of silicon and manganese on the shell growth and mold temperature maps have been examined in relation to the peritectic transformation for varying carbon contents. Results of thermodynamic and kinetic simulations using ThermoCalc and its kinetic module—DICTRA predicted that silicon expands the carbon content range to values between (0.12 pct C to 0.21 pct C) where peritectic behavior occurs and that manganese shrinks the carbon content range and shifts the range to lower carbon contents (0.06 pct C to 0.12 pct C). The results of these simulations were used to guide the selection of chemistries examined in the dip test experiments with the aim of validating the software predictions. Dip tests were performed at similar steel making temperatures that were used for the software simulations between 1600 °C and 1650 °C. Both software results and experimental observation showed relatively good agreement for the compositions examined. [ABSTRACT FROM AUTHOR]

• A novel Ca-Fe-Si composite material (CIS) immobilized Cd can be divided into non acid-stable Cd (9.4%), moderately acid-stable Cd (22.5%) and acid stable Cd (68.1%). • Non acid-stable Cd in CIS was mainly bound by sulfate, silicate and carbonate (Cd 2 SiO 4 , CdSO 4 , and CdCO 3) or co-precipitated with the corresponding calcium salts. • Moderately acid-stable Cd was mainly bound by magnesium-aluminum-silicon containing minerals or loosely bound by manganese iron minerals. • Acid-stable Cd remaining undissolved at pH < 2.42 included Cd 5 (PO 4) 2 SiO 4 , CdFe 2 O 4 and ferromanganese minerals strongly bound Cd. • It was by multilateral fixation mechanisms that CIS possessed marvelous high efficiency in Cd immobilization and strong resilience to environmental acidification. Ca-Fe-Si material (CIS), a novel composite material rich in calcium, iron, manganese and silicon showed marvelous immobilization properties for heavy metal(loid)s in soils. To elucidate the acid stability of Cd fixed by CIS (CIS-Cd) and the underlying immobilization mechanisms, the acid dissolution characteristics of CIS-Cd were investigated by using acid titration method and X-ray diffraction (XRD) technique. The results showed that CIS-Cd had distinctive acid buffering capacity in different pH ranges. Based on the titration curve between dissolution rate of CIS-Cd and pH, CIS-Cd can be divided into non acid-stable Cd (9.4%), moderately acid-stable Cd (22.5%) and acid-stable Cd (68.1%). XRD analysis of CIS-Cd at different pH intervals and the correlation curves of dissolution rates of Cd and concomitant elements indicated that non acid-stable Cd was mainly bound by carbonate, silicate and sulfate (CdCO 3 , Cd 2 SiO 4 and CdSO 4) or co-precipitated with the corresponding calcium salts. Moderately acid-stable Cd was mainly bound by magnesium-aluminum-silicon containing minerals or electrically bound by manganese iron minerals. Acid-stable Cd remaining undissolved at pH < 2.42 included CdFe 2 O 4 and ferromanganese minerals strongly bound Cd. It was by multilateral fixation mechanisms that Ca-Fe-Si material possessed marvelous immobilization capability for Cd and strong resilience to environmental acidification as well. The findings implicated that proper combination of calcium-iron-silicon containing minerals could develop novel promising amendments with high efficiency in heavy metal(loid)s immobilization and strong resilience to environmental change. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Silicomanganese fumes (SMF) are industrial waste and a potential low-cost adsorbent for the removal of contaminants from water. In this study, the adsorption performance of SMF and NaOH-modified SMF (SMF-Na) for the removal of tetracycline (TC) from an aqueous solution was investigated. The characterization results showed the presence of functional groups (SiO 2 , -OH and C-O-C), a considerably higher surface area of the SMF-Na (142.59 m2 g−1) compared to the SMF (7.73 m2 g−1). The TC adsorption was favored under acidic conditions (pH 2–3) and increased with an increasing amount of adsorbent. The adsorption equilibrium was achieved in 360 min, and the presence of Na+ ions insignificantly influenced the TC adsorption. The Avrami model fitted better to the kinetic data with R2 = 0.995. The isothermal data was well represented by the Redlich-Peterson and Langmuir model. The maximum monolayer adsorption capacity of SMF and SMF-Na was 117 and 129 mg g−1, respectively. The thermodynamic results confirmed that the TC adsorption was endothermic and predominantly governed by physical forces. The removal of TC onto SMF and SMF-Na was maintained above 90 % even after five regeneration cycles The results suggested that SMF-Na is a promising alternative adsorbent for the removal of tetracycline antibiotics from wastewater streams. [Display omitted] • SMF is an industrial waste that treated with NaOH showed good removal of the antibiotic tetracycline. • Adsorption equilibrium is reached in 240 min, regardless of concentration. • The Avrami model showed a good fit to the kinetic data. • The isothermal data were well represented by the Langmuir monolayer model. • Adsorption is governed by physical interactions of an endothermic nature. [ABSTRACT FROM AUTHOR]

This study investigated the possibility of developing self-compacting concrete (SCC) utilising silicomanganese fume (SMF), an industrial waste material. SCC was produced by replacing cement with 10, 20, 30, 40, 50, 60, 70, 80 and 90% SMF. First, an assessment of the fresh properties of 10 SCC mixtures was carried out, and then mixtures satisfying the fresh requirements were selected for further evaluation. Plastic shrinkage and setting time of the fresh SMF-SCC mixtures were measured, and thereafter the mechanical properties and drying shrinkage were evaluated. The incorporation of SMF increased the dosage of superplasticizer required for a certain flow, but it enhanced the filling ability and passing ability of SCC. In addition, the incorporation of SMF increased the plastic and drying shrinkage, as well as initial and final setting times. Although there was an improvement in mechanical properties of SCC mixtures containing 10 and 20% SMF, increasing the quantity of SMF beyond 20% negatively affected the mechanical properties. Furthermore, the use of SMF decreased the cost of SCC by 7–42% and the CO2 emission decreased by 10–68%. [ABSTRACT FROM AUTHOR]

Specific total loss is one of the most important evaluation indexes for the magnetic properties of non-oriented electrical steel sheets. The aim of this study is to investigate the influencing mechanisms of laser cutting parameters as well as the sample characteristics on the specific total loss of thin non-oriented electrical steel sheets processed by laser cutting using a machine learning method. Eight input parameters were finally considered; namely, silicon and manganese contents, thickness of the steel sheets, laser nozzle diameter, laser power, cutting speed, the pressure of process gas, and laser defocus, while one output parameter, the specific total loss, was evaluated. It was found that the specific total loss was positively correlated with the sample thickness, but negatively correlated with silicon and manganese contents, the process gas pressure and laser nozzle diameter. In addition, laser power and cutting speed exhibit complicated non-linear relationships with the specific total loss. [ABSTRACT FROM AUTHOR]

This study investigates the utilization of high-ash coal as an alternative reductant in the smelting of silicomanganese, aiming to reduce the carbon footprint of traditional coke-based processes. Experiments were conducted using an ore-thermal furnace with a transformer power of 200 kVA to simulate industrial conditions. The charge consisted of manganese ore (Mn - 36%), slag from refined ferromanganese production (MnO - 25%), and high-ash coal (ash content 40%–50%). Chemical analysis of the produced alloy showed a composition of Mn–70%, Si–20%, C–1.28%, P–0.06%, and S–0.05%, meeting the standards for silicomanganese. The results demonstrate that high-ash coal can replace coke without compromising the quality of the alloy. This approach not only indirect CO _2 emissions but also leverages the abundant availability of high-ash coal, which is often discarded as waste. The study highlights the potential for significant environmental benefits and cost savings, making this method a viable alternative for sustainable industrial practices. The findings support the industrial application of high-ash coal in silicomanganese production, contributing to more eco-friendly and economically feasible metallurgical processes.

The cold bonding method was used to prepare silico manganese slag artificial aggregate. By exploring the influence of granulator inclination angle, frequency and pelletizing time on the performance and particle size distribution of silico manganese slag aggregate, the optimal granulation process condition was determined as the inclination angle 50° frequency 15 Hz and ball formation time 70 min. On this basis, the effects of solid and liquid alkali activator additions, curing temperature and two kinds of silicon manganese slag on aggregate properties were studied. The results show that when the liquid activator and solid activator are added in an amount of 16. 2% and 20%, respectively, and the curing temperature is room temperature, the prepared aggregate has the best performance. The compressive strength of the 7 day cylinder is 17. 6 8. 9 MPa. The single ball strength of the aggregate prepared from TYGM is better than that of BLGM. The aggregate strength of TYGM reaches a maximum of 18. 88 MPa at 112 d, while that of BLGM reaches a maximum of 13. 31 MPa at 119 d. [ABSTRACT FROM AUTHOR]

Airborne particulate matter (PM) is a concern for both occupational health and the environment, and, in the ferroalloy industry, the level of such particles in the air can be considerable. Small, low-cost sensors for measuring PM have generated interest in recent years, providing widespread monitoring of PM levels in the environment. However, such sensors have not yet been sufficiently tested under conditions relevant for the indoor environment of the metallurgical industry. This study aims to bridge this gap by benchmarking the commercial, low-cost Nova PM SDS011 particle sensor in two different ferroalloy plants. Benchmarking was performed against the Fidas 200S, which has been suitability-tested and certified according to the latest EU requirements (EN 15267, EN 16450). Twelve Nova sensors were tested over 3 months at a silicomanganese alloy (SiMn) plant, and 35 sensors were tested during 1 month at a silicon (Si) plant. The results showed that the low-cost Nova sensors exhibited all the same trends and peaks in terms of PM concentration, but measured lower dust concentrations than the Fidas 200S. The difference was larger at the silicon plant, which is in line with expectations, due to the size and mass fractions of particles in Si dust compared to SiMn dust, and to the larger measurement range of the Fidas, measuring down to 180 nm compared to the Nova which measures down to 300 nm. Despite the difference in absolute values, the Nova sensors were found to provide data for comparing dust levels over time for different processes, at different locations, and under different operational conditions. [ABSTRACT FROM AUTHOR]

Recent studies by Safarian et al. and Kim show that carbothermic smelting processes for SiMn alloys proceed by multiple reactions consisting of oxidation of carbon, simultaneous reduction of MnO and SiO2 species, and distribution of Mn and Si elements between slag and alloy. A consideration of reaction equilibrium shows that the smelting reaction system is described by the reaction of carbon oxidation and that of distribution of Mn and Si. The distribution reaction with respect to SiMn alloy and slag is described by the following, 2 MnO + Si = 2 Mn + SiO 2 , where oxide species in parenthesis indicate in solution of slag and elements in square brackets in solution of carbon saturated SiMn alloy. The present investigation of chemical analyses of alloy and slag taken from laboratory experiment by Swinbourne et al. and industrial smelting operation shows that the distribution reaction system is univariant for carbon saturated SiMn alloy, and the distribution reaction equilibrium is specified with temperature. As it is driven by reducing reactions, the distribution reaction equilibrium is established as either chemically or electrochemically depending on the characteristic of reducing reactions. For smelting of SiMn alloy with the standard grade composition, the chemical equilibrium is established at 1600 °C. At temperatures lower than 1600 °C, carbon at the interface of alloy and slag is oxidized by free oxygen ion, O2−, in slag at the gas phase pressure of PCO = 1 atm, and the electrochemical equilibrium is attained. [ABSTRACT FROM AUTHOR]

A calculation of thermodynamic model of the recovery process of manganese from oxide system MnO - CaO - Al2O3 - SiO2 - MgO is presented in the study. For the calculation, the following composition in % was used: 35.00 Mn3O4; 7.70 Fe2O3; 1.29 Al2O3; 0.50 MgO; 0.001 P2O5; 15.20 - 30.00 SiO2; 30 - 40 CaO. A complex aluminum-siliconmanganese alloy (AlSiMn) of the following grades AlSiMn 1, AlSiMn 2, AlSiMn 3, AlSiMn 4 and silicomanganese SiMn 26, are used as a reducing agent in the traditional technology. The HSC Chemistry 10.0 program (Outotec, Finland) was used for the calculation. The calculations were carried out using the "Equilibrium composition" module at a pressure of 0.1 MPa, in the temperature interval of 1400 - 1700 oC. The calculation results are presented in the form of graphical dependences of the extraction of manganese (nMn), on the temperature (t), on the slag basicity (CaO/SiO2) and the concentrations of silicon and aluminum in the complex alloy - AlSiMn ([Si]AlSiMn and [Al]AlSiMn). By means of thermodynamic calculations and mathematical planning of experiments, it was possible to establish the influence of the studied factors on the of manganese extraction. [ABSTRACT FROM AUTHOR]

Alkali-activated materials are produced by chemically polymerizing the aluminosilicate materials using alkaline activators, which can effectively lower the greenhouse-gas emissions (approximately 73%) released by ordinary Portland cement (OPC). Silicomanganese slag is a large solid waste discharged from the ferroalloy industry in China that can pollute the environment and occupy resources. In this paper, the slag in alkali-activated material was replaced with silicomanganese slag to address the disposal of silicomangaese slag. The flowability, setting times, compressive and flexural strengths, micro-structure and freeze-thaw resistance of alkali-activated silicomanganese slag concrete (AASSC) with varied substitution ratios, volume fractions of steel fibers and alkali-activated modulus (MS) were exploited. As a results the compressive strengths at 56 days of AASSC with a 10% substitution ratio of silicomanganese slag reached over 80 MPa and over 132 MPa with the 3% steel fiber dosage. AASSC still reached 91 MPa and 45 MPa with 60% and 100% substitution ratios by cooperating 2% steel fibers, respectively. When the freeze-thaw cycle number reached 300, the compressive strengths of AASSC with the replacement ratios of 10%, 60% and 100% were 84%, 74% and 51% of their original values by cooperating 2% steel fibers, respectively; AASSC with the numerous substitutions of 60% and 100% were destroyed at 600 and 300 freeze-thaw cycles, respectively. AASSC with a 10% substitution ratio and 2% steel fiber content is suitable for excellent performance, and a 60% substitution ratio can also be applied to construction for the massive utilization of silicomanganese slag. [ABSTRACT FROM AUTHOR]

Salvia miltiorrhiza is an important medicinal plant that experiences significant growth and biomass losses when cultivated on cadmium (Cd) contaminated soils. High Cd accumulation in plant tissues also increases the risk of metal entry into the food chain. In this study, we proposed that Cd accumulation in S. miltiorrhiza can be restricted through plant growth regulators and nutrient management. Therefore, S. miltiorrhiza seedlings were transplanted into mixed nutrient soil for two weeks, then treated with 30 mg kg-1 CdCl2, 200 mg kg-1 Na2SiO3·9H2O, and 100 mg kg-1 MnSO4, and simultaneously sprayed with 10 mg L-1 ALA on the leaves one week later. This study showed that elevated Cd accumulation significantly reduced plant growth and biomass. This growth inhibition damaged photosynthetic machinery and impaired carbon assimilation. In contrast, 5-aminolevulinic acid (ALA) significantly promoted the biomass of S. miltiorrhiza, and the dry weight of plants treated with ALA combined with manganese (Mn)/silicon (Si) increased by 42% and 55% as compared with Cd+Mn and Cd+Si treatments. Exogenously applied ALA and Si/Mn significantly activated antioxidant enzymes and promoted the growth recovery of S. miltiorrhiza. Further, exogenous ALA also reduced the Cd concentration in S. miltiorrhiza, especially when combined with Si. Compared with the Cd+Si treatment, the Cd+Si+ALA treatment reduced the Cd concentration in roots and leaves by 59% and 60%, respectively. Gene expression analysis suggested that ALA and Si significantly up-regulated genes associated with Cd transport. Other genes related to heavy metal tolerance mechanisms are also regulated to cope with heavy metal stress. These results indicated that the combined action of ALA and Si/Mn could reduce Cd-toxicity by increasing chlorophyll content and changing oxidative stress and can also affect Cd accumulation by regulating gene expression. [ABSTRACT FROM AUTHOR]

A new thermoluminescence (TL) material, Mn:CaF 2 transparent glass ceramic, was prepared from silicomanganese slag, and its feasibility as thermoluminescence dosimeter (TLD) for environmental radiation dose detection was verified for the first time. When added 19.28 wt% slag and heat-treated at 710 °C, the samples showed better sensitivity to absorbed radiation, along with a linear dose response characteristic ranging from 50 to 500 Gy. Moreover, the irradiated samples should be stored in dark environment for less than 40 days. The reproducibility of glow curves could be achieved after annealing at 300 °C for 20 min before the next irradiation. Finally, the kinetic parameters were calculated and the glow mechanism was clarified. The results indicate show that the new TL material, Mn:CaF 2 transparent glass ceramic prepared using silicomanganese slag, is a potential candidate for radiation detection applications, which also provides a new and valuable approach for the resource utilisation of silicomanganese slag. [ABSTRACT FROM AUTHOR]

To study the applicability of solid waste replacement of concrete raw materials and the effect on concrete properties, through the orthogonal test of 16 groups of fly ash-silica manganese slag recycled concrete test blocks, the effects of fly ash volume substitution for cementitious material, silicon manganese slag volume substitution for sand, and recycled aggregate mass substitution for coarse aggregate on concrete slump, cube compressive strength and splitting tensile strength were studied under different substitution amounts. The results show that when the substitution amount of fly ash is 40% (volume fraction), the increasing rate of concrete slump is the largest, which is 14. 5%, and the cube compressive strength and splitting tensile strength are reduced, and the reduction rate are 7. 2% and 22. 8%, respectively. The substitution of silicon manganese slag reduces the slump of concrete, and when the substitution amount of silicon manganese slag is 80% (volume fraction), the reduction rate of the compressive strength and splitting tensile strength is the smallest, which are 0. 5% and 11. 5%, respectively. The substitution of recycled aggregate reduces the slump of concrete, and when the substitution amount of recycled aggregate is 100% (mass fraction), the reduction rate of the cube compressive strength is 1. 9%, and the reduction rate of splitting tensile strength is 12. 4%. The cube compressive strength of concrete is predicted by the optimized model NSGM(1,4). The average relative error of model simulation is 0. 542%, and the average relative error of model prediction is 2. 727%. [ABSTRACT FROM AUTHOR]

Background: Silicon (Si) is a multiple stress attenuator element in plants, however more research is needed to elucidate the actions in the plants defense system with low nutrition of manganese (Mn) for a prolonged period, and the attenuation mechanisms involved in the effects of Mn deficiency on energy cane with high fiber content. Thus, the objective of this study was to evaluate whether Si reduces the oxidative stress of the energy cane grown in low Mn in nutrient solution, to mitigate the effects of Mn deficiency, improving enzymatic and non-enzymatic defense, uptake of Mn the plant growth. Methods: An experiment was carried out with pre-sprouted seedlings of Saccharum spontaneum L. in a 2 × 2 factorial scheme in five replications in which the plants were grown under sufficiency (20.5 μmol L−1) and deficiency (0.1 μmol L−1) of Mn combined with the absence and presence of Si (2.0 mmol L−1) for 160 days from the application of the treatments. The following parameters were evaluated: accumulation of Mn and Si, H2O2, MDA, activity of SOD and GPOX, total phenol content, pigments, and quantum efficiency of PSII. Results: Mn deficiency induced the oxidative stress for increase the H2O2 and MDA content in leaves of plants and reduce the activity of antioxidant enzymes and total phenols causing damage to quantum efficiency of photosystem II and pigment content. Si attenuated the effects of Mn deficiency even for a longer period of stress by reducing H2O2 (18%) and MDA (32%) content, and increased the Mn uptake efficiency (53%), SOD activity (23%), GPOX (76%), phenol contents, thus improving growth. Conclusions: The supply of Si promoted great nutritional and physiological improvements in energy cane with high fiber content in Mn deficiency. The results of this study propose the supply of Si via fertirrigation as a new sustainable strategy for energy cane cultivation in low Mn environments. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Glass-ceramic foams were successfully synthesized entirely from silicomanganese slag and feldspar tailings through an autocatalytically induced foaming process. • The effects of silicomanganese slag contents and sintering temperatures on the morphology and phase composition of glass–ceramic foams were investigated. • The multiphase co-melting mechanism of silicomanganese slag and feldspar tailings was revealed. • The influence of the high-temperature pyroplastic state on foaming behavior and pore morphology was elucidated. Utilizing solid waste to produce foam material has become a significant direction in resource recycling. This study focuses solely on using silicomanganese slag and feldspar tailings as raw materials, utilizing a powder sintering process to produce autocatalytic foaming glass–ceramic foam. We formulated four mix ratios based on the compositional characteristics of the silicomanganese slag and feldspar tailings. The study then explored the evolution of phase formation and macroscopic pore morphology under varying preparation temperatures. Moreover, through multi-phase co-melting experiments, this work unveiled the high-temperature molten mass generation mechanism between silicomanganese slag and feldspar tailings. Our findings reveal that the glass melt generated from silicomanganese slag particles and the 'solid–liquid erosion behavior' of feldspar particles play pivotal roles in the formation of high-temperature co-melt substances. As the sintering temperature increases, the mixed powder exhibits three different states of high-temperature molten mass, which are the reasons for the evolution of the macroscopic pore structure. It is suggested that the addition of silicomanganese slag should be less than 50 %, and the heat treatment temperature should be below 1145 °C in preparing glass–ceramic foam with silicomanganese slag and feldspar tailings. The sample with 40 % silicomanganese slag and 60 % feldspar tailings, treated at 1140 °C, yielded glass–ceramic foam with a compressive strength of 1.68 MPa, apparent density of 0.279 g/cm3, porosity of 81.7 %, and thermal conductivity of 0.074 W·m−1·K−1. In summary, this study provides a novel approach for the high-value utilization of silicomanganese slag and offers an economical route for developing lightweight, eco-friendly structural materials. [ABSTRACT FROM AUTHOR]

The deterioration of the refractory lining represents a significant problem for the smooth operation in the ferroalloys industry, particularly in the production of silicomanganese, due to the periodic requirements of substitution of the damaged refractory. Within this context, magnesia refractories are commonly employed in the critical zones of the furnaces used in silicomanganese production since the slag involved in the process has a basic character. The behavior of MgO–ZrO2 ceramic composites with different ZrO2 nanoparticles (0, 1, 3, and 5 wt.%) contents in the presence of silicomanganese slags is proposed in this manuscript. XPS, XRD and SEM–EDX were used to evaluate the properties of the ceramic composite against the silicomanganese slag. The static corrosion test was used to evaluate the corrosion of the refractory. Results suggest that corrosion is controlled by the change in slag viscosity due to the reaction between CaZrO3 and the melted slag. Besides, ZrO2 nanoparticles located at both triple points and grain boundaries act as a barrier for the slag advance within the refractory. The utilization of MgO refractories with ZrO2 nanoparticles can extend the life of furnaces used to produce silicomanganese. [ABSTRACT FROM AUTHOR]

A method for the determination of eight metal elements in silicon manganese smelting slag by inductively coupled plasma mass spectrometry (ICP-MS) was established by using HCl-HNO3-HF-HClO4 mixed acid as digestion system, adding 1. 0 mL of 100 g/L hydroxylamine hydrochloride solution to dissolve the residue, s electing appropriate isotopes, and using 103 Rh as internal standard to determine Cr, Co, Ni, Cu, Zn and Cd, and 193Ir as internal standard to determine Tl and Pb. It was found that the sample pretreatment selection HC1 : HNO3 : HF : HClO4 = 5 : 5 : 5 : 1, and 1.0 mL 100 g/L hydroxylamine hydrochloride solution was added in the redissolution stage to completely digest the sample. The determination results of the elements to be determined in the sample were not interfered by the matrix composition. The KED mode and interference coefficient correction method were used to eliminate the interference of mass spectrometry. By drawing the calibration curve and measuring the bank of the process, the correlation coefficients of each element calibration curve were all greater than 0. 999 9. The detection Units were between 0. 006 mg/kg and 0. 19 mg/kg. The limits of quantification were between 0. 018 mg/kg and 0. 57 mg/kg. The actual sampes of silicomanganese stag were determined, the relative standard deviations (RSD, n = 11) were in the range of 0.83%--4.1%, and the recoveries were 94.7%--106%. After personnel comparison test, the relative deviation was between --4. 54% and 4. 24%. The results showed that the method was stable and reliable and could meet the requirements of analysis and detection of eight trace metal elements in silicon manganese smelting stag. [ABSTRACT FROM AUTHOR]

At present, Kazakhstan has established production of ferrosilicomanganese, while refined ferromanganese is not produced. This is primarily due to a lack of high quality feedstock, as well as a lack of theoretical and applied research into new production conditions. To address these issues we conducted large-scale laboratory tests on smelting medium-carbon ferromanganese by one-stage silicothermic method. As a result of these tests, medium-carbon ferromanganese meeting the standard grade with more than 80 % manganese content was produced. [ABSTRACT FROM AUTHOR]

The work highlights the study on chemical and phase composition of stripping waste and manganese ore tailings at Zhairem deposit. It was shown that the overburden rocks have a complex mineral composition and contain 14.6 wt. % manganese in (Mn2O3)3MnSiO3 in braunite form. Enrichment tailings are represented mainly by 76.4 wt. % calcite and contain 2.4 wt. % of braunite. On the basis of manganese ore concentration wastes in the temperature range of 200°C - 800°C, phosphate materials were synthesized due to an acid-thermal method. Alongside, their composition and aqueous solubility were studied as well. It was shown that the product synthesized at 200°C contains mainly acidic and medium diphosphates of calcium, silicon and manganese (III) monophosphate. The mentioned product has a high aqueous solubility of 92.4 %. Increasing the synthesis temperature to 400°C and 600°C grows the depth of phosphate anion dehydration process, and results in the formation of poorly soluble calcium polyphosphates Ca(PO3)2 and trivalent manganese Mn(PO3)3 that partially turn into a glassy state at 800°C. [ABSTRACT FROM AUTHOR]

The anodic dissolution of the Mn5Si3 electrode in 0.5 M H2SO4 + (0.0025–0.05) M NaF solutions is studied by the methods of polarization, capacitance, and impedance measurements. The kinetic order of the reaction of dissolution of silicide with respect to NaF as a function of the potential and the differential capacitance as a function of the potential and the concentration of NaF are calculated. It is shown that the effect of sodium fluoride, which activates the anodic dissolution of Mn5Si3 in a sulfuric acid solution, is associated with a weakening of the passivating effect of oxygen-containing silicon compounds and manganese oxides; with an increase in the concentration of NaF, the role of manganese in the kinetics of anodic processes on silicide increases and the role of silicon decreases. The mechanisms and kinetic laws of the anodic processes taking place on the Mn5Si3 electrode are discussed. [ABSTRACT FROM AUTHOR]

The relevance of the work is caused by the need to study the problem of import dependence of Russia on manganese raw materials. The aim of the research is to study the dynamics of commodity flows (production, import, export, consumption) of manganese products (ores and concentrates, ferromanganese, silicomanganese and manganese metal); development of recommendations to optimize the turnover of manganese products. Methods: statistical, graphic, logical. Results. Manganese products are one of the most mass import-dependent goods in Russia.More than 1,6 million tons, which is 72% of their consumption,were imported in 2018.Import dependence on manganese ores as of 2018 is 100% of consumption (1,3 million tons were imported), silica manganese – 46% (import is 192 thousand tons), manganese metal – 100% (import is 68 thousand tons) and ferromanganese – 10% (import is 21 thousand tons). Consumption of manganese concentrate increased from 285 thousand tons in 1996 to 1,3 million tons in 2018 (+7,2%/year). In near future, the ferrous metallurgy of Russia will not be able to do without the import of manganese concentrate. Serious regulation of imports of manganese concentrate from Kazakhstan, South Africa and Gabon is required, as well as Russian investments in foreign manganese mining and ferroalloy companies. National consumption of silica manganese increased from 170 thousand tons in 1998 to 455 thousand tons in 2017 (+5,3%/ year), and production increased from 50 to 355 thousand tons/year (+6,5%/year). Import volumes of silicomanganese remain at the same level – 170–190 thousand tons/year, although in 2003–2008 import volumes were 310–435 thousand tons/year. The reduced imports from Ukraine were replaced by supplies from Georgia, Kazakhstan and Norway. National consumption of ferromanganese increased slightly – from 193 thousand tons in 1996 to 262 thousand tons in 2017 (+0,6%/year), and production volumes increased sharply from 50 to 260 thousand tons/year (+6,5%/year). The volume of imports of ferromanganese at the same time seriously decreased from 130 to 21 thousand tons/year (–3,9%/year). Ferromanganese came out of full import dependence in import-independent category. The demand for a new commodity product – metallic manganese occurred. Its consumption increased from 0,3 thousand tons in 1996 to 68 thousand tons in 2018 (+12,2%/year). In the context of total imports of manganese ferro-alloys the phenomenon of counter import-export trade (export to 63 thousand tons/year of ferromanganese and to 133 thousand t/year of silicomanganese), until the formation of the direction of net exports of ferromanganese (to 41 thousand tons/year of ferromanganese)appeared.

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we followed the formation sequences of the different manganese silicides by performing simple annealing at different temperatures of the deposited manganese (Mn) on silicon (Si) substrate. Phase change and transition temperatures have been reported. In situ x-ray diffraction (XRD) is used in two different chambers and the results obtained are presented in 3D figures. The surface roughness is first obtained by atomic force microscopy (AFM) and then by scanning electron microscopy (SEM) characterization. The latter is also used for the detection of the different superimposed layers after the formation of the different silicides obtained in the solid phase reaction (SPR). Focus ion beam (FIB) cuts were used to analyze the different layers obtained during silicide formation at these temperatures. In this study, we have obtained Mn15Si26 for high temperatures (above 850°C). Finally, an epitaxy of HMS (Mn15Si26) is obtained at high temperatures with a simple annealing process. [ABSTRACT FROM AUTHOR]

The influence of the welding energy-technological modes on the physical and mechanical properties of weld seams obtained by submerged arc welding, made on the basis of silicomanganese slag, is determined. Various welding modes allows the required penetration depth and the absence of external defects is investigated. It is shown that changes in the current strength value, welding speed and voltage exert influence upon the physical and mechanical properties of the weld seam and the hydrogen concentration in the weld seam. [ABSTRACT FROM AUTHOR]

The possibility of using silicon with the nanoclusters of manganese atoms for creating photoresistors in the spectral region λ = 1.2–3 μm is shown. It is found that such photodetectors possess a threshold sensitivity of about 10–11 W at a wavelength of 1.55 μm. The quantum efficiency at a wavelength of 2 μm exceeds 10% and is 0.1% at a wavelength of 2.5 μm, which makes it possible to use the impurity photosensitivity of silicon with the nanoclusters of manganese atoms for creating high-resolution array photodetectors operating in the spectral region of up to 2.5 μm. [ABSTRACT FROM AUTHOR]