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PL
Tegoroczny raport Plastics Europe „Tworzywa sztuczne w obiegu zamkniętym – analiza sytuacji w Europie” pozwala jeszcze lepiej zrozumieć gospodarkę tworzyw sztucznych o obiegu zamkniętym i zmiany, jakie się dokonały na przestrzeni ostatnich lat. Nowe dane wskazują, że choć cyrkularność systemu tworzyw sztucznych przyspiesza, to wciąż jest dużo do zrobienia.
EN
In the context of achieving sustainable development goals, continuously pushing possible extended research and attempting to implement the respective outcomes in expanding a circular economy for a broad range of products are high priorities. In this paper, we considered disposable tannery sludge as a matter of concern and proposed an innovative framework for placing tannery sludge in the economic value chain via an encapsulation technique-based construction product development. We used polypropylene plastic and a cement-water matrix as encapsulation materials, and the encapsulated tannery sludge bodies were tested for their drop strength, water absorbing behaviour, ability to leach chromium and tendency to lose weight upon ignition. Value of water absorption for the prepared double layered encapsulated tannery sludge bodies was 1.332%, the drop strength performance index arrived was 90% and 0.0001 µg/g of Chromium leaching was found in Toxicity Characteristic Leaching Procedure (TCLP) and shown 67% weight loss in thermogravimetric (TGA) analysis. The results confirmed the possibility of ecocompatible disposal and recirculation of tannery sludge for the sustainable production of building blocks in the form of encapsulated bodies. The outcomes of our work add upon a new perspective to the existing literature regarding the environmentally positive utilization of tannery sludge in the production of building blocks.
EN
The aim of the paper is to identify the direction of evolution, the conditions of organisation and the impact of the new concept of digital innovation ecosystem in boostering circularity development. The traditional model of innovation brokerage and the new circularity broker paradigm in the development of the circular economy is presented. The authors discuss the circularity broker as an IT interface, equipped with wide range of IT tools, and above all, self-learning applications with AI elements. The circularity broker is accompanied by its watch dog, i.e. a set of IT tools used to search, process and transfer information dedicated to specific stakeholders, exactly when they need this information. The concept of circular brokerage is anchored in the area of the regional clusters dedicated to circular economy development.
EN
Background: The concepts of closed loop supply chain and circular economy are both based on the introduction of circular flow of material goods. Both concepts are becoming increasingly important not only due to the significance of reducing negative environmental impacts, but also due to supply chain disruptions caused by the COVID pandemic and the Russian invasion of Ukraine. The aim of this article is to determine the role of closed loop supply chains in circular economy and to determine the possibilities of interplay regarding practical application of these concepts. Methods: The research method used in this paper is the review of the existing literature. The reviewed literature is related to the areas of closed loop supply chains and circular economy. The study focuses not only on the possibilities of interplay between these two concepts, but also similarities, differences, and related operational concepts, such as slowing or intensifying loops of flows of material goods. Results: The results concern the possibilities of interplay between closed loop supply chains and circular economy and possibilities related with building the closed loop supply chains in circular economy. One of such possibilities is building circular networks consisting of closed loop supply chains. It might include collaboration related to reducing the use, reusing, and recycling of material resources. Conclusions: The main possibility of interplay between closed loop supply chains and circular economy is collaboration between actors of different supply chains aiming at building circular networks. The main research implication is providing a basis for further research related with building closed loop supply chains and circular networks in circular economy.
EN
In the self-designed flotation column simulation system, the foaming characteristics of the micro-bubble countercurrent contact flotation column used in the hematite cation column flotation process are systematically studied. The objective of this study is to investigate the bubble generation by a bubble generator in the flotation column. The bubble image was obtained by the high-speed camera recorder, and the bubble diameter was calculated and analyzed by image processing software. The distribution characteristics of the bubble size under different aeration conditions and with different reagent concentrations were investigated. The results show that as the aeration increases, the average diameter bubbles increases, the bubble size distribution changes from narrow to wide, and the number of small bubbles decreases. The cationic collector GE-609 can change the bubble shape. As the concentration increases, the bubble shape gradually changes from an irregular shape to a standard spherical shape. When the concentration of GE-609 exceeds 2.5 mg/dm3, the average circularity C of the bubbles in the bubble group stabilizes at 1, and the increase in concentration no longer changes the bubble shape. GE-609 also has an efficient foaming effect, as the concentration increases, the bubble diameter distribution changes significantly, the proportion of small bubbles increases, and the proportion of large bubbles decreases significantly. When the critical concentration is exceeded, the bubble diameter distribution probability density peak width no longer changes significantly. Compared with the two types of alcohol foaming agents, GE-609 produces a bubble Sauter diameter close to that of 2-octanol and slightly lower than terpineol.
EN
In this paper circularity of three different machine tools by Virtual Machine was analyzed. To get circularity we make a ball bar test according to ISO 230-4. The test is very common in engineering for a quick diagnostic Computerized Numerical Control (CNC) technical conditions. We implemented earlier calculations of Volumetric Error in our Virtual Machine. Then we simulated testing of circularity of CNC machine tools. The place to take the test was chosen randomly from Uniform Distribution in three different kinds of machine tools. Those machines had different characteristics of kinematic errors and squareness and also different sizes of working space. We observed significant differences in the indicator (circularity) depending on the place where the test was taken. Moreover we showed that there was no reason to take the test in the center of working table.
EN
This study presents analysis of circular test used according to ISO 230-4 for quick diagnostic Computerized Numerical Controls condition. We built virtual machine, which implements earlier calculations of Volumetric Error. Using this Virtual Machine we simulated testing of circularity of Computerized Numerical Control machine tools. Virtual test was taken in ten different places for three different machine tools. Those machines had different characteristics of kinematic errors and squarness and also different sizes of working spaces. We observed significant differences in those indicators in dependence of place where the test was taken.
PL
Zaprezentowano analizę wyników próby okrągłości wg ISO 230-4, stosowanej do szybkiej diagnostyki stanu obrabiarek sterowanych numerycznie. Zbudowano wirtualną maszynę, realizującą wyznaczoną doświadczalnie mapę błędów przestrzennego pozycjonowania. Przeprowadzono z jej użyciem symulację próby okrągłości obrabiarek sterowanych numerycznie. Symulację wykonano w dziesięciu różnych położeniach przestrzeni roboczej dla trzech różnych maszyn. Obrabiarki różniły się zarówno charakterystykami błędów kinematycznych i prostopadłości, jak i rozmiarami przestrzeni roboczej. Wykazano istotne różnice w wartości błędu okrągłości i sferyczności w zależności od położenia w polu roboczym maszyny.
8
Content available Noncircularity of Demodulated Radar Signal
EN
The output of the quadrature demodulator is generally regarded as a complex signal that is circular if only the demodulator is well balanced. In the paper we analyze properties of quadrature demodulators, particularly digital one, and show that the output is noncircular also if the input signal is nonstationary. Then we find sources of this noncircularity and show that they stem from transients of the low-pass demodulator filter. This is quite important because nonstationary inputs are quite typical in radar where power of echoes depends strongly on range. In the first sections we also review complex random signals and properties of circularity and properness.
PL
W pracy przedstawiono wyniki badań diagnostycznych obrabiarki CNC. Dokonano analizy wybranych błędów obrabiarki CNC identyfikowanych za pomocą pręta teleskopowo kulowego. Ocenie jakościowej poddano typowe odchyłki geometryczne, takie jak: odchyłkę okrągłości, odchyłkę prostopadłości osi, odchyłkę okresową. W trakcie pomiarów wyznaczono ponadto błąd nawrotu i luz zwrotny w badanej osi. Wskazano na zalety oraz wady szybkiego testu QC10. Omówiono przyczyny powstawania badanych błędów oraz wskazano podstawowe sposoby ich minimalizacji. Uzyskane wyniki badań przedstawiono w postaci wykresów i tabel.
EN
This paper presents results of CNC machine tool testing. Analyses of error were performed with ballbar method. This method allowed to investigate geometric errors as circularity, squarness, straightness as well as reversal spikes and backlash. Evaluated errors were discussed and compensation procedures were proposed. Obtained results were described in tables and figures.
10
Content available remote The effect of cooling rate on the microstructure of nodular cast iron
EN
The study gives the results of the investigations concerning an effect of the casting cooling rate ( casting made from nodular iron used as a starting material for austempering to produce ADI) on the morphology of nodular graphite and metallic matrix composition. The features of the microstructure morphology were determined on a LUCIA computer program using castings of 10, 20, 40 and 60 mm diameter. It has been proved that increasing the casting diameter from 10 to 60 mm (i.e. reducing the cooling rate) increases the content of graphite from 10 to 12% and an average area of the precipitations from about 150 to 440 [mikro]m2, while it reduces the number of the graphite precipitations in 1 mm2 from about 700 to 260, the mean value of the shape factor from 0,96 to 0,84, and pearlite content in the matrix from about 96% to 84% The chemical composition seems to have no significant effect, the only exception being Mo whose presence increases in a visible way pearlite content in the matrix at each cooling rate. The obtained results, and specifically the distribution of the frequencies of occurrence of the examined morphological features of graphite, confirm the vast possibilities that the LUCIA computer program of image analysis offers in evaluation of the effect of technological parameters on cast iron microstructure.
PL
Przeprowadzono badania doświadczalne w celu zaobserwowania wpływu spoiny w materiale wyjściowym na odkształcenia sprężyste w wytłoczkach cylindrycznych bez kołnierza i z kołnierzem, w wytłoczkach o kształcie L i elementach giętych o kształcie V. Badania przeprowadzono z blachami stalowymi ocynkowanymi E220BH, spawanymi laserem. Wpływ spoiny zaobserwowano w wytłoczkach cylindrycznych bez kołnierza i elementach giętych, natomiast w wytłoczkach cylindrycznych z kołnierzem i o kształcie L, czyli o większej sztywności, wpływ ten był niewielki i w praktyce możliwy do pominięcia. Badania przedstawione w tym opracowaniu są wycinkiem badań prowadzonych w ramach projektu INETFORSMEP.
EN
Experiments have been carried out to determine the influence of a weld in the initial material on springback deformation in cylindrical drawpieces without and with a flange, in L-shape drawpieces and in V-shape bent elements. The tests were performed on zinc coated laser welded E220BH sheets. The welded joint influence has been observed in the cylindrical drawpieces without a flange and in the bent elements while that in the cylindrical drawpieces with a flange and in the L-shape ones was small and negligible in practice. The investigation presented in this paper are only a part of investigations of drawpieces springback carried out in project INETFORSMEP.
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