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Number of results: 55
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Abstract

This investigation is concerned with the extraction of nugget copper particles from copper recovery plant slag which recycled of copper scrap. For this purpose, the Falcon concentrator was used because of its enhanced gravity properties. The Falcon concentrator has a fast spinning bowl which creates a centrifugal force to separate fine size minerals on the basis of their density differences. In the tests, the tailings of the copper recovery plant were used and the test sample was divided into two groups and one of them was classified in narrow particle sizes. The operational parameters were determined as particle size, centrifugal force and washing water pressures. The water pressure and centrifugal force have an inversely proportional relationship. Because of this phenomenon, the G/P parameter was created. The test conditions were applied to the whole distribution sample and narrow size distribution samples in the same way.

The test results indicate that the average grade was elevated from 1.04% to 6.50% with the recovery of 15.07% and 619% enrichment ratio for narrow sizes, whereas grade was elevated to 4.36% with 13.24% recovery and 415.94% enrichment ratio for the whole distribution. As a result, the recovery and grade values of concentrates are not good enough for gravity concentration process for both samples. However, this process was applied to the double recycled material and the lower recovery, grade values can be tolerated because of concentrate is nugget copper metal. The concentrate can also be washed in cleaning table for increasing the grade value for adding to initial feed of plant. This process can, therefore, supply important earnings not only economically but also environmentally.

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Authors and Affiliations

Murat Kademli
Namik Atakan Aydogan
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Abstract

This paper presents the results of studies on functional possibilities of the optimization of geometric sizes and the design development of specialized resonance concentrating link (concentrator-sonotrode) with enlarged radiating surface. Developed theoretical model allows to determine the value of longitudinal and transverse sizes of each part of concentrating link providing the achievement of required features of the ultrasonic vibrating systems (gain factor of the unit and its resonance frequency). To verify the efficiency of designed model, the geometric sizes of resonance concentrating link were determined using the finite-element complex, which showed that the disagreement did not exceed 10%. The efficiency of proposed model at the determining of size and resonance characteristics of concentrating link was proved by the experiments. Theoretical and experimental studies helped to optimize the size of concentrating link while the vi- brating system developed on its base enabled the enlargement of radiating surface without decreasing the radiation intensity for the realization of technologies of cavitation treatment of liquid media
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Authors and Affiliations

Sergei S. Khmelev
Vladimir N. Khmelev
Roman N. Golykh
Andrey V. Shalunov
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Abstract

Detection of explosives vapors is an extremely difficult task. The sensitivity of currently constructed detectors is often insufficient. The paper presents a description of an explosive vapors concentrator that improves the detection limit of some explosives detectors. These detectors have been developed at the Institute of Optoelectronics. The concentrator is especially dedicated to operate with nitrogen oxide detectors. Preliminary measurements show that using the concentrator, the recorded amount of nitrogen dioxide released from a 0.5 ng sample of TNT increases by a factor of approx. 20. In the concentrator an induction heater is applied. Thanks to this and because of the miniaturization of the container with an adsorbing material (approx. 1 cm3), an extremely high rate of temperature growth is achieved (up to 500 °C within approx. 25 s). The concentration process is controlled by a microcontroller. Compact construction and battery power supply provide a possibility of using the concentrator as a portable device.

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Authors and Affiliations

J. Wojtas
B. Rutecka
S. Popiel
J. Nawała
M. Wesołowski
J. Mikołajczyk
S. Cudziło
Z. Bielecki
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Abstract

One of the concepts of the ventilation rate control in buildings with dense and unpredictable occupancies is based on the CO2 measurements. There are many limitations regarding the validity of CO2 measurement inputs as suitable to the ventilation rate control. Verifying research has been conducted in an air-conditioned auditorium, in the real conditions at altered ventilation air thermal parameters and variable occupancy. The CO2 and the number concentrations of the fine and coarse aerosol particles(> 0.3 μm) and bioaerosol particles (bacteria and staphylococci) as well as the indoor air thermal parameters were measured in the individual sectors of the occupied area. The sensory assessments and instrumental determinations of the acceptability of indoor air quality (ACC) were also performed. The ventilation control strategy based, apart from the CO2 measurements, on the continuous monitoring of the perceived air quality (PAQ) in the auditorium sectors has been suggested. The PAQ monitoring could be accomplished by aerosol concentration measurements and the ACC instrumental determinations. This strategy should ensure a desired PAQ in sectors which benefit the occupants' comfort, health and productivity as well as energy savings not only in the case of its implementation in the considered auditorium.
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Authors and Affiliations

Bernard Połednik
Marzenna Dudzińska
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Abstract

This study shows the results of flotation concentration of mica minerals from kaolinised granite taken from the “Bašića bare” deposit – Kobaš, Srbac, The Republic of Srpska (B&H). Mineralogical composition of kaolinised granite is as follows: kaolinite, feldspar, quartz, and mica. After separating >0.630 mm, and <0.043 mm size class where kaolinite is concentrated, the rest is –0.630+0.043 mm class containing quartz, feldspar and mica. The mica concentrate was obtained by the flotation concentration, while feldspar and quartz were in the flotation underflow. According to the mineralogical analysis, the most abundant minerals are mica and chlorite/clays, while quartz and feldspar occur much less, and accessory minerals are represented in trace. The semi-quantitative mineralogical analysis obtained by the X-ray powder diffraction (XRPD) method of the mica concentrate amount to: mica ≈55%, chlorite/clays ≈35%, quartz ≈5%, feldspars (plagioclase and K-feldspars combined) ≈5%.

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Authors and Affiliations

Živko T. Sekulić
Slavica R. Mihajlović
Jovica N. Stojanović
Branislav B. Ivošević
Vladan D. Kašić
Miroslav R. Ignjatović
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Abstract

The present study modelled the effects of operational parameters on the performance of the Falcon concentrator. For this purpose, the Falcon L40 concentrator was tested in narrow particle-size fractions (−600 + 425 μm, −425 + 300 μm, −300 + 212 μm, −212 + 150 μm, −150 + 106 μm, and −106 + 75 μm) at different washing water pressures and artificial gravity forces generated by a spinning bowl. The test samples were prepared artificially, comprising 2% magnetite (Fe3O4) and 98% calcite (CaCO3) by weight. The recovery and grade values of the 60 experimental conditions were investigated and compared for different operational parameters, including particle-size distributions, water pressures, and artificial gravity forces. Two empirical models were developed using non-linear regression analysis to indicate the effects of the operating parameter of the Falcon concentrator on its recovery and grade values. The operational parameters were found to impact the separation performance considerably. Therefore, the Falcon concentrator should operate under optimum conditions, which can be easily predicted using these models, to achieve improved recovery and grade values.
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Authors and Affiliations

Namik Atakan Aydogan
1
ORCID: ORCID
Murat Kademli
1
ORCID: ORCID

  1. Hacettepe University, Mining Engineering Department, Turkey
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Abstract

The region’s development potential is a set of endogenous features that determine the growth of the local economy. It supports the development of knowledge, innovation and eff ective competition on global markets. The publication argues that saturation with potential may not be enough to cause economic growth. The distribution of potential is also important: concentration is its catalyst. The study proposes a method for measuring the concentration of potential. It has also been shown that the size of the regional economy depends on the distribution of potential in the region.

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Authors and Affiliations

Michał Nadolny
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Abstract

Research concerning temporal variations of suspended sediment concentration during period of high water stages was done in the lower course of the Obra River near Międzyrzecz (Western Poland). The analysis regarding dependence of mean suspended sediment concentration and discharge allowed to determine the way of suspended sediment supply to the river bed during high water stages. It was supposed that exposures of glacial and fluvioglacial sediments in high concave banks could be an important factor influencing the amount of delivery of suspended material. Besides, normal hysteretic loops (oriented clockwise) were observed in cross-sections 4 and 5. That fact would suggest that transported material originates form the Obra River bed or its vicinity. The process of sediment accretion was observed on a fragment of drowned floodplain during high water stages. Collection of samples of freshly deposited sediment and grain size analysis allowed to illustrate the mechanism of forming floodplain sediments. It also was possible to draw near conditions of forming such sediments in the past.
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Authors and Affiliations

Zygmunt Młynarczyk
Marcin Słowik
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Abstract

Serum concentration of thyroid hormones in healthy dogs varies according to age, sex, breed or professional activity. The aim of this study was to determine the influence of both age and dogs’ work involvement on TSH and thyroid hormones values. Thyroid-stimulating hormone (TSH), total thyroxine (tT4) and free thyroxine (fT4) were tested in the serum of 57 healthy, German Shepherd dogs. The dogs were divided into study groups according to age: dogs aged 3 to 6 years (A), dogs over the age of 6 years (B) and involvement: police-working dogs (C) and accompanying animals (D). Mean values of TSH, tT4 and fT4 ranged from 0.19 to 0.31 ng/ml, 15.58 to 17.25 nmol/L and 11.83 to 17.89 pmol/L, respectively. The highest values of TSH were in group B and the lowest were in group A, while there was an inverse dependence in case of fT4 concentration. The highest mean values of tT4 were in dogs in group C and the lowest in group B. There were statistically significant differences in TSH (p=0.007) and fT4 (p=0.003) concentrations between the age groups. The results indicate that a dog’s age is an important factor in the case of thyroid profile results interpretation.
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Authors and Affiliations

I. Taszkun
1
A. Milczak
2
G. Kalisz
3
P. Wilkołek
1
J. Zwolska
4
M. Szczepanik
1

  1. Subdepartment of Clinical Diagnostics and Veterinary Dermatology, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głeboka 30, 20-612 Lublin, Poland
  2. Department and Clinic of Animal Internal Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głeboka 30, 20-612 Lublin, Poland
  3. Department of Biopharmacy, Faculty of Pharmacy, Medical University of Lublin, ul. W. Chodzki 4a, 20-093 Lublin, Poland
  4. Department and Clinic of Animal Surgery, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głeboka 30, 20-612 Lublin, Poland
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Abstract

Nontuberculous mycobacteria (NTM) have recently emerged as important bacterial pathogens of animals and humans. Of particular concern is the high level of antimicrobial resistance displayed by these organisms, which complicates treatment and potential successful outcomes. Here, we evaluated the potential of Carlina acaulis L. as a source of novel anti-mycobacterial agents. Our goal was to measure the activity of aqueous, ethanol, and chloroform C. acaulis root extracts against 99 NTM strains. GC-MS spectroscopy analyses were performed to deliver qualitative and quantitative data on the composition of C. acaulis extract. In our study, we have shown for the first time the activity of C. acaulis extracts against NTM. The highest activity was exhibited by the chloroform extract, which inhibited the growth of more than 90% of the strains at the dose of 100 μg/mL (MIC90 = 100 μg/mL). The results of the GC-MS analysis of the C. acaulis chloroform extract contributed to the identification of 37 compounds, with carlina oxide as the most representative compound (69.52%) followed by 3,4-dihydro-2H-phenanthren- -1-one (6.54%) and stigmast-5-en-3-ol (4.14%). Our results indicate that C. acaulis chloroform and ethanol extracts have potential for treatment of NTM infections and that this plant contains anti-mycobacterial compounds.
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Authors and Affiliations

K. Puk
1
J. Wawrzykowski
2
L. Guz
1

  1. Department of Biology and Fish Diseases, Faculty of Veterinary Medicine, University of Life Sciences, Akademicka 12, 20-033 Lublin, Poland
  2. Department of Biochemistry, Faculty of Veterinary Medicine, University of Life Science in Lublin, Akademicka 12, 20-033 Lublin, Poland
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Abstract

Nontuberculous mycobacteria (NTM) have recently emerged as important bacterial pathogens of both animals and humans. In this study, we aimed to evaluate the effect of a combination of ten antibiotics with an inhibitor of efflux pumps (EPI), i.e. berberine (BER), against 6 strains of NTM. Our results showed that the BER potentiated the anti-mycobacterial activities of the antibiotics. Overall, our findings show the importance of BER in increasing the efficacy of antibiotics in NTM.
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Bibliography


Gaba S, Saini A, Singh G, Monga V (2021) An insight into the medicinal attributes of berberine derivatives: a review. Bioorg Med Chem 38: 116143.
Gentry EJ, Jampani HB, Keshavarz-Shokri A, Morton MD, Velde DV, Telikepalli H, Mitscher LA, Shawar R, Humble D, Baker W (1998) Antitubercular natural products: berberine from the roots of commercial hydrastis canadensis powder. Isolation of inactive 8-oxotetrahydrothalifendine, canadine, beta-hydrastine, and two new quinic acid esters, hycandinic acid esters-1 and -2. J Nat Prod 61: 1187-1193.
Guz L, Puk K (2022) Antibiotic susceptibility of mycobacteria isolated from ornamental fish. J Vet Res 66: 69-76.
Menichini M, Lari N, Rindi L (2020) Effect of efflux pump inhibitors on the susceptibility of Mycobacterium avium complex to clarithromycin. J Antibiot 73: 128-132.
Puk K, Guz L (2020) Occurrence of Mycobacterium spp. in ornamental fish. Ann Agric Environ Med 27: 535-539.
Song L, Wu X (2016) Development of efflux pump inhibitors in antituberculosis therapy. Int J Antimicrob Agents 47: 421-429.
Van Ingen J, Boeree MJ, Van Soolingen D, Mouton JW (2012) Resistance mechanisms and drug susceptibility testing of nontuberculous mycobacteria. Drug Resist Updat 15: 149-161.
Wang Y, Fu H, Li Y, Jiang J, Song D (2012) Synthesis and biological evaluation of 8-substituted berberine derivatives as novel an-ti-mycobacterial agents. Acta Pharm Sin B 2: 581-587.
Zhou XY, Ye XG, He LT, Zhang SR, Wang RL, Zhou J, He ZS (2016) In vitro characterization and inhibition of the interaction between ciprofloxacin and berberine against multidrug-resistant Klebsiella pneumoniae. J Antibiot 69: 741-746.
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Authors and Affiliations

K. Puk
1
L. Guz
1

  1. Department of Biology and Fish Diseases, Faculty of Veterinary Medicine, University of Life Sciences, Akademicka 12, 20-033 Lublin, Poland
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Abstract

During the cruise of the research ship r/v Oceania owned by the Institute of Oceanology of the Polish Academy of Sciences in Sopot a research on mineral suspension concentration and dispersion distributions was conducted. The research area included the western part of the Baltic Sea, the Danish Straits, the Norwegian Sea, the waters around Spitsbergen and the North Atlantic Ocean. Samples of water were collected from the surface layer. They were subjected to microscopic analysis. Measurements were done with a projection microscope (magnification lOOOx) and using the Burker's table. After counting the particles dispersion distribution was determined. The largest concentration of mineral suspension was noted offshore in the Norwegian Sea and around Spitsbergen and the smallest in the central Atlantic Ocean.

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Authors and Affiliations

Henryk Gurgul
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Abstract

Data sets gathered continuously in air monitoring systems are never entirely complete. The problem of missing data in monitoring measure series often has to be solved by modeling. A new method of air monitoring data modelling was tested in the paper. Regional diurnal concentration courses (RDCCs) were used as the main source of knowledge of predicted time series during specified days. The paper presents a comparison of predicted and measured diurnal concentration patterns of two frequently used parameters in air monitoring (PM10 and NO2). The analysis was based on hourly time series of these air pollutants collected in a 3-year period at nine monitoring stations in the Lodz Region. It was shown that well determined regional diurnal concentration patterns could be useful to missing data modelling at the specified monitoring site. Improvement of modelling accuracy is possible after modification of modelling results by adding local difference vectors (LDVs), describing the specificity of the monitoring station.
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Authors and Affiliations

Szymon Hoffman
Rafał Jasiński
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Abstract

The intensive agricultural use of the land affects both quantity and quality of river water in the catchment area. Such impact is visible also in the Szreniawa River catchment in the Małopolskie Voivodeship. The combination of intensive plowing and soil susceptibility to water erosion are the main causes of soil and nutrients depletion during the heavy rainfall. The aim of the study is to determine changes in the water quality in the Szreniawa River catchment compared to the agri-culture use and precipitation level.

The quality of surface water has been analysed in the river catchment area in three sampling points. The concentration of the total suspended soils in the samples collected after heavy rainfall in August 2017 reached a value of 837 mg·dm–3. The average concentrations of N-NO3 in the years of 2016–2019 ranged from 0.16 to 13.46 mg·dm–3, with the highest val-ues in the summer (up to 13.46 mg·dm–3). The concentration of N-NH4 and P-PO4 in the Szreniawa water was affected by precipitation. The highest value of average concentration of N-NH4 3.00 mg·dm–3 was recorded in the autumn of 2019 in the middle section of the river. The highest value of P-PO4 0.90 mg·dm–3 was recorded in the autumn of 2019 mostly due to water erosion of the loess areas. Erosion has been caused by the short-term heavy rainfall. As a result, suspended solids, soluble and insoluble phosphorus compounds leaked to the river.

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Authors and Affiliations

Agnieszka W. Kowalczyk
ORCID: ORCID
Marek Kopacz
ORCID: ORCID
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Abstract

Koumiss has beneficial therapeutic effects on bacterial diseases. Four antibacterial com- pounds from yeasts ( Kluyveromyces marxianus and Saccharomyces cerevisiae) in koumiss were evaluated for their antibacterial effects against three Gram-negative bacteria, three Gram-positive bacteria and five pathogenic Escherichia coli strains. The antibacterial compounds from yeasts in koumiss were extracted, and their main components were determined. The inhibition zones were analyzed, and their minimum inhibition concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined. Aqueous phases of Kluyveromyces marxianus and Saccharomyces cerevisiae at pH 2.0 and 8.0 produced larger inhibition zones than those in other phases, and then antibacterial compounds from K. marxianus (K2, pH=2.0; K8, pH=8.0) and S. cerevisiae (S2, pH=2.0; S8, pH=8.0) were obtained. Their main components were organic acids and killer toxins. K2 had more propanoic acid and S2 had more oxalic acid than others. The inhibition zones of K2, K8, S2 and S8 against three Gram-negative bacteria and three Gram-positive bacteria were 12.03-23.30 mm, their MICs were 0.01-0.13 g/mL, and MBCs were 0.03-0.50 g/mL. Meantime, the inhibition zones of K2, K8, S2 and S8 against five pathogenic E. coli were 16.10-25.26 mm, their MICs were 0.03-0.13 g/mL, and MBCs were 0.13-1.00 g/mL. These four antibacterial compounds from yeasts in koumiss had broad antibacterial spectrum. In addition, K2 and S2 were better than K8 and S8.
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Authors and Affiliations

Y.J. Chen
1 2
C.G. Du
1 3
Y.Q. Guo
1
Y.F. Zhao
1
C. Aorigele
2
C.J. Wang
3
H. Simujide
2
W. Aqima
2
X.Y. Zhang
1

  1. Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, P.R. China
  2. College of Animal Science, Inner Mongolia Agricultural University, Hohhot 010018, P.R. China
  3. College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, P.R. China
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Abstract

The aim of the paper is to measure and forecast concentration of regional development potential on a regional basis. The study covered 14 GUS features, which measure the development potential. The forecast, nominal values and processes’ dynamics were calculated for data from 2010 to 2020, using author made method. The study reveals that key factors determining the diversification of the distribution of the potential include the relation of large agglomerations to their regional surroundings. Therefore, we are dealing with growth poles with different impact levels. Since 2010, the process of concentrating potential in Poland has taken different directions. In poorly developed regions, we observe constant distribution values. Most regions, especially those with medium and high levels of economic development, are characterized by a dynamic increase in the level of concentration 5% to 6% annually. This means that the growth poles «move away» from their surroundings and strengthen their position. Simultaneously, they slightly reduce the distance to the strongest developed region in Poland (Mazowsze). By 2020, these trends will remain unchanged, however regions with a moderately low level of development will observe the fastest growth.

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Authors and Affiliations

Michał Nadolny
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Abstract

Due to the occurrence of zinc and lead ore deposits in dolomite rocks, the sphalerite concentrates obtained from these ores contain an admixture of dolomite. In practice, a substantial amount of magnesium included in zinc ores passes to the last production stage, i.e. zinc electrolysis. The magnesium present in electrolyte impairs electrical conductance and appears in the technical and economical indexes. This paper deals the attempts to remove magnesium removal from initial sphalerite concentrates by means of chemical flotation using spent electrolyte derived from zinc electrolysis. The authors attempt to substantiate the existing relationships, as well as to derermine the optimum conditions for the procedure suggested. The leaching efficiency of magnesium amounted to about 80%, and is dependent upon the stage of the leaching. Losses of zinc were below 2%, and the magnesium concentration in solution amounted to about 20%. These solution can produce magnesium and zinc, which will be presented in the following paper.

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Authors and Affiliations

Andrzej Jarosiński
Adam Kozak
Sylwester Żelazny
Piotr Radomski
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Abstract

Steel and cast-iron products, due to their low price and beneficial properties, are the most widely used among metals; their consumption has become an indicator of the economic development of countries. The characteristics of iron raw materials, in relation to current metallurgical requirements, are presented in the present this article. The globalization of the trade and development of steelmaking technologies have caused significant changes in the quality of raw materials in the last half-century forcing improvements in processing technologies. In many countries, standard concentrates (at least 60% Fe) are almost twice as rich as those processed in the mid-20th century. Methods of quality assessment have been improved and quality standards tightened.

The quality requirements for the most important raw materials ‒ iron ores and concentrates, steel scrap, major alloy metals, coking coal, and coke, as well as gas and other energy media ‒ are reviewed in the present paper. Particular attention is paid to the quality testing methodology. The quality of many raw materials is evaluated multi-parametrically: both chemical and physical characteristics are important. Lower-quality parameters in raw materials equate to significantly lower prices obtained by suppliers in the market.

The markets for these raw materials are diversified and governed by separate sets of newly introduced rules. Price benchmarks (e.g. for standard Australian metallurgical coal) or indices (for iron concentrates) apply. Some raw materials are quoted within the framework of the commodity market system (certain alloying components and steel scrap). The abandonment of the long-established system of multi-annual contracts has led to wide fluctuations in prices, which have reached a scale similar to that of other metals.

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Authors and Affiliations

Mariusz Krzak
Andrzej Paulo
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Abstract

The purpose of the present study was to extract high added value titanium from Ti-doped Seaside Magnetite Concentrated (Ti-SMC), which has a high potential reserve for Ti-Fe with 4–6% Ti, 50–52% F e, 1–2% A l, and 1–2% Mg content by applying innovative, economical, environmentally friendly methods. A gitaion HCl leaching was applied to the Ti-SMC sample at different leaching temperatures (25–50–75–90°C), at acid concentrations (8–10–12 N ), and leaching times (30–60– –120–240 min) in atmospheric conditions. A fter the leaching experiments under the indicated conditions, the optimization of the leaching experiments was determined with Ti% recovery that dissoluted by elemental analysis, and the titanium recovery values reached the maximum value with increased leaching time at 50°C and 10 N HCl acid concentration; and 65% Ti was recovered in 30 minutes, 67% in 60 minutes, 74% in 120 minutes, and 82% Ti in 240 minutes. F or Ti-SMC, leaching was carried out at 50°C leaching temperature and at 10 N acid concentration for 480 minutes, and a 92% Ti extraction value was achieved. A ccording to the extraction results of all leaching experiments, the leaching temperature of 50°C, the acid concentration of 10 N , and the leaching time of 480 minutes were determined as the optimum conditions. In this study, it was emphasized that this resource is a potential reserve, which has not been used as a source before, with 92% Ti extraction with atmospheric acid leaching, which is an environmentally friendly method, consuming less energy than Ti-SMC, which is difficult and expensive to extract with traditional methods.
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Authors and Affiliations

Elif Uzun Kart
1
ORCID: ORCID
Mümin Kırman
1
ORCID: ORCID

  1. Marmara University, İstanbul, Turkey
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Abstract

All the restructuring programs that have been implemented in Polish bituminous coal mining as a primary way to reduce mining costs relied on the increased concentration of mining operations. Those efforts especially involved a significant simplification of existing or newly developed structures for accessing or cutting the deposits intended for extraction; implementation of advanced mining technologies, and upgrading of machines used in mine faces. However, in order for these to deliver the expected results, it is important to organize mining operations in such a way so that those advanced, and usually very expensive, mining-related fixed assets – machinery and equipment – are used sensibly. In order to define a reasonable production capacity of each longwall face, it is necessary to apply various criteria related to the mining and technical aspects, occupational safety, and organizational and economic aspects. Only then will it be possible to evaluate the expected effects in the field of concentration of mining in a mining company and in the mines which form part of such enterprises. Decisions in this respect should always be made at the planning stage, based on analysis results. The aim of this article is to explore the factors involved in concentration-related decision-making in mining companies, including the underlying mining/technical, organizational, and economic/ /financial aspects. A mining company is understood as a group of related mines, the primary business operations of which include bituminous coal mining, processing, and trading.

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Authors and Affiliations

Patrycja Bąk
ORCID: ORCID
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Abstract

Gravity Recovery and Climate Experiment (GRACE) mission data is widely used in various fields of science. GRACE explored changes of the gravity field regularly from April 2002 to June 2017. In the following research, we examine variance of signal contained in two different formats of GRACE data: standard spherical harmonics and mass concentration blocks (so-called “mascons”) solutions, both provided in the most recent releases. For spherical harmonics-based solution, we use monthly gravity field solutions provided up to degree and order (d/o) 96 by three different computing centers, i.e. the NASA’s Jet Propulsion Laboratory (JPL), the German Research Center for Geosciences (GFZ) and the Center for Space Research (CSR). For the mass concentration blocks, we use values of total water storage provided by the CSR, JPL and the Goddard Space Flight Center (GSFC) computing centers, which we convert to spherical harmonic coefficients up to d/o 96. We show that using the anisotropic DDK3 filter to smooth the north-south stripes present in total wate storage obtained from standard spherical harmonics solution leaves more information than common isotropic Gaussian filter. In the case of mascons, GSFC solution contains much more information than the CSR and JPL releases, relevant for corresponding d/o. Differences in variance of signal arise from different background models as well as various shape and size of mascons used during processing of GRACE observations.

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Authors and Affiliations

Artur Lenczuk
ORCID: ORCID
Grzegorz Leszczuk
Anna Klos
ORCID: ORCID
Janusz Bogusz
ORCID: ORCID
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Abstract

The main source of spatial information on concentration and deposition of air pollutants in Poland is the continental scale EMEP model with 50 km x 50 km grid. The coarse resolution of the EMEP model may be insufficient for regional scale studies. A new proposal is the application of the national scale atmospheric transport model FRAME (Fine Resolution Atmospheric Multi-pollutant Exchange), originally developed for the United Kingdom. The model works with 5 km x 5 km spatial resolution and the air column is divided into 33 layers. FRAME was used here to assess the spatial patterns of yearly averaged air concentrations, and wet and dry deposition of sulphur and nitrogen compounds for the area of Poland. This study presents preliminary results of the modeling of the yearly average concentrations as well as dry and wet depositions of SO,, NO, and NH, for Poland. FRAME results were compared with available measurements from the monitoring sites and national deposition budget with the EMEP and IMGW estimates. The results show close agreement with the measured concentrations expressed by determination coefficient close to O. 7 for both SO, and NO . The dry and wet deposition budgets for FRAME are also in close agreement with the EMEP and GIOŚ estimates. The FRAME model, despite its relatively simple meteorological parameterizations, is well suited to calculate the spatial pattern of annual average concentration and yearly deposition of atmospheric pollutants which was earlier presented for the UK and was shown in this paper for Poland. The model can also be used to analyze the impact of individual point sources or different emission sectors on spatial pattern of air concentration and deposition as well as testing the changes in deposition resulting from future emissions reduction scenarios.
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Authors and Affiliations

Maciej Kryza
Marek Błaś
Anthony J. Dore
Mieczysław Sobik
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Abstract

No adequate reaction has been observed of the decreased contaminant loads discharged by Łódź, particularly the loads of phosphorus, on its concentration in the Ner River. That’s why the im-pact of sediment on phosphorus content in the water was evaluated. Not only was the amount of phosphorus taken under consideration but also the equilibrium phosphate concentration (EPCo). The meaning of EPCo is that any phosphate concentration in the water below this value will lead to phos-phorus release from sediments. Performed study shows that in the Puczniew cross-section EPCo is higher then phosphorus concentration in water, thus with mean concentration of PO4 equal to 9.5 mg PO4·dm–3 phosphorus could be released from sediments. This concentration in Lutomiersk cross-section, however, equals 1.2 mg PO4·dm–3.

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Authors and Affiliations

Józef Mosiej
Hubert Komorowski
Agnieszka Karczmarczyk

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