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Number of results: 7
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Abstract

Investigations of operating parameters of widely used sand mixers reveal a wide variability range in the values of parameters associated

with their power demand. Power efficiency of manufacturing processes has received a great deal of attention lately, which encourages the

research efforts to optimise this aspects of operation of machines and installations as well. In the first place these machines

and installations have to work properly as a part of the process line- which applies also to moulding sand mixers. Experiments conducted

by the authors suggest that the same goal can be achieved at variable energy input levels. To obtain information about the power demands

of sand mixers requires the use of highly specialised equipment, methodology and result processing procedures. This study provides a brief

characteristic of measurement equipment and results of measurements taken on a unit AG-015 (based on a roller mixer) and a laboratory

rotor mixer.

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Authors and Affiliations

K. Smyksy
E. Ziółkowski
R. Wrona
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Abstract

The article presents current state of the structure of hard coal enrichment plants in Poland, taking the capacity, the range of grain enrichment and the type of equipment used into account. This data were presented in a tabular format for each Polish Coal Company operating on the Polish market. The article was also present simplified: flow sheet of the steam and coking coal enrichment system. Based on the presented data, the planned needs and trends were described in terms of increasing production efficiency, minimizing water consumption and safety of work. A list of research and development works which must be undertaken were also presented as well as factors determining the technological development of the processing plants.

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Authors and Affiliations

Ireneusz Baic
Wiesław Blaschke
Bronisław Gaj
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Abstract

For a long time creativity, innovativeness and entrepreneurship have been at the heart of studies on economic growth of regions and cities. In the paper the three notions are scrutinised together to propose conceptual approach to establishing research and development pathways, based upon three-stage identification of: research problems, project patterns and relational mechanisms. The paper is concluded with a 63 Box – the approach helping to navigate throughout project preparation phase.

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Authors and Affiliations

Marcin Budziński
Marcin Baron
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Abstract

Grade control is crucial for ensuring that the quality of extracted ore aligns with the geological model and mining plan. This process optimises production, reduces dilution, and maximises profits. It involves geological modelling, sampling, assaying, and data analysis. However, adhering to short-term planning in mining operations can be challenging due to operational bottlenecks that arise during the grade control process and blast design, along with their associated costs. Industry standards for grade control require acquiring extensive information and knowledge to achieve a high level of certainty, which takes time. Despite that, time constraints may necessitate making decisions under risk with incomplete information. In such cases, it is important to consider the opportunities, risks, likelihood, consequences, and potential success associated with each alternative. This study presents the testing results of alternative quantitative analytical methods on samples from the Barruecopardo tungsten deposit in Spain. Spectrometric techniques, including Delayed Gamma Neutron Activation Analysis (DGNAA), Laser-induced Breakdown Spectroscopy (LIBS), and Field Portable X-ray Fluorescence (FPXRF), were employed to determine the tungsten content. Based on the findings of this investigation, a real-time decision-making tool for grade control in open-pit mining has been developed. This tool utilises representative samples directly from the blasting debris, considering the inherent risks and uncertainties associated with the process
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Authors and Affiliations

Ruben Alcalde Martín
1
ORCID: ORCID
Isidro Diego
1
ORCID: ORCID
César Castañón
1
ORCID: ORCID
Teresa Alonso-Sánchez
1
ORCID: ORCID

  1. Oviedo University, Oviedo School of Mines, Spain
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Abstract

A ceria loaded carbon nanotubes (CeO2/CNTs) nanocomposites photocatalyst was prepared by chemical precipitation, and the preparation conditions were optimized using an orthogonal experiment method. HR-TEM, XRD, UV-Vis/DRS, TGA and XPS were used to characterize the photocatalyst. Nitrogen adsorption-desorption was employed to determine the BET specific surface area. The results indicated that the photocatalyst has no obvious impurities. CeO2 was dispersed on the carbon nanotubes with a good loading effect and high loading efficiency without agglomeration. The catalyst exhibits a strong ability to absorb light in the ultraviolet region and some ability to absorb light in the visible light region. The CeO2/CNTs nanocomposites photocatalyst was used to degrade azo dye Acid Orange 7 (40 mg/L). The optical decolorization rate was 66.58% after xenon lamp irradiation for 4 h, which is better than that of commercial CeO2 (43.13%). The results suggested that CeO2 loading on CNTs not only enhanced the optical decolorization rate but also accelerated the separation of CeO2/CNTs and water.

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Authors and Affiliations

Tao Wen
Yu-bin Tang
Fang-yan Chen
Bing-yu Mo
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Abstract

This paper discusses issues related to optimising the technological parameters of the process of brazing gold in a vacuum

furnace. An investigation of the brazing process was carried out for materials used in constructing components for aircraft engine

fuel systems. The vacuum brazed material was AMS 5510 stainless steel (in the form of plates and pipes). AMS 4787 (BAu-4) was

used as the brazing filler. In particular, the influence of the method of preparing the surface on solder spreading and the thickness

of the diffusion zone were analysed. The best spreading of solder was obtained for nickel plated surfaces. When the sample surface

was more rough or scratched, the effect of the spreading of solder was limited and the diffusion process of the solder into the base

material became dominant. Moreover, the influence of the brazing temperature on microstructure changes and on interdiffusion

of the AMS 5510 stainless steel/BAu-4 solder system was determined. It was observed that an increase in the brazing temperature

modifies the morphology of the formed joint by forming a massive and rounded phase. Furthermore, an increase in the brazing

temperature enhances the exchange of components.

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Authors and Affiliations

M. Hebda
P. Kaczor
K. Miernik

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