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1

Insights Into Estimation of Sand Permeability: From Empirical Relations to Microstructure-based Methods

Bodak Bartłomiej, Sobótka Maciej

Studia Geotechnica et Mechanica

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2024

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Vol. 46, nr 1

1--20

EN

This study evaluates various methods for estimating soil permeability using microtomographyderived data and compares them to the conventional laboratory approaches. Different methods, including measurement in custom-designed permeameter at micro- CT-compatible scale, empirical equations, simulated sifting, semi-theoretical equations, pore-network modeling, and lattice-Boltzmann simulations, were applied to samples of sandy soils with distinct microstructural properties. The empirical equations showed varied results, highly dependent on the method chosen. The simulated sifting method was able to adequately estimate the granulometric properties of the soil, allowing the use of empirical permeability formulations for substantially small samples. Semi-theoretical equations based on the microstructural properties presented reasonable agreement for some samples. The pore-network modeling approach demonstrated computational efficiency but lacked accuracy. The lattice-Boltzmann method required significant computational resources but did not provide substantially closer alignment with the measured hydraulic properties of some samples. None of the simulations was able to properly determine the permeability of silty and organically contaminated sand. The study highlights the complexity of permeability estimation, emphasizing the need for choosing volumes of interest, resolution of micro-CT scans, and methods that match specific soil characteristics and available computational resources.

2

Badania wpływu promieniowania elektromagnetycznego na komponenty matryc biosensora

Kłos-Witkowska Aleksandra, Martsenyuk Vasyl

Pomiary Automatyka Robotyka

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2023

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R. 27, nr 4

57--63

PL

W pracy za pomocą zmian przewodności zbadano zmiany konformacyjne proteiny BSA oraz jej kompleksów (BSA-Au oraz BSA-NAA) pod wpływem promieniowania UV oraz MF aplikowanego frakcyjnie w dawkach (3 × 10 min oraz 6 × 10 min) oraz w sposób ciągły (30 min, 60 min). Wykonano analizę porównawczą wpływu promieniowania UV i mikrofalowego w dawkach ciągłych i frakcyjnych na BSA, BSA-Au, BSA-NAA oraz przeanalizowano czułość na pole elektromagnetyczne z zakresu UV i MF dla badanych substancji. Udowodniono efekt przyspieszonych zmian konformacyjnych pod wpływem pola elektromagnetycznego z zakresu UV i MF. Wykazano wpływ czynników na stabilność BSA i jej kompleksów zależny od: rodzaju czynnika, sposobu jego aplikacji oraz czasu ekspozycji. Najbardziej czuły na pole elektromagnetyczne okazał się kompleks BSA-Au.

EN

In this study, the conformational changes of BSA protein and its complexes (BSA-Au and BSA-NAA) under UV and MF radiation applied in fractional doses (3 × 10 min and 6 × 10 min) and continuously (30 min, 60 min) were investigated by means of conductivity changes. A comparative analysis of the effect of UV and microwave radiation in continuous and fractional doses on BSA, BSA-Au, BSA-NAA was performed, and the sensitivity to UV and MF electromagnetic fields of the tested substances was analysed. The effect of accelerated conformational changes under the influence of UV and MF electromagnetic field was proved. The influence of the factors on the stability of BSA and its complexes was shown to depend on: the type of agent, the method of its application and the exposure time. The most sensitive to the electromagnetic field turned out to be the complex BSA-Au.

3

Research on New Al-Ag-Mo Alloys Dedicated to Wire Applications in Overhead Power Lines

Grzebinoga Justyna, Mamala Andrzej, Ściężor Wojciech, Kowal Radosław

Journal of Casting & Materials Engineering

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2023

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Vol. 7, no. 1

9--14

EN

The latest research work in the field of electric power systems focuses on the development of new wire materials which will allow the increase of the transmission capacity of power lines currently in use. The reason for this research was the often limited possibilities of continuous and failure-free transmission of electricity. In this paper, the authors present research on a new aluminium-based alloy dedicated for use as a conductive braid in the HTLS cable group. There are many technical solutions for this group of cables on the market, although they are solutions with a number of disadvantages, ranging from their high price, various operational shortcomings, complicated installation techniques, and ending with the risk of monopolistic practices, which is related to the inability to attract several competitive suppliers. The main aim of the research was to develop a new alloy based on aluminium with the addition of silver and molybdenum dedicated for use in special overhead power cables. Experimental research on new materials focused on obtaining the necessary knowledge to produce an overhead wire from these alloys with higher current carrying capacity in relation to the currently used conventional wire materials based on aluminium.

4

Konduktancja połączeń spawanych torów prądowych szynoprzewodów aluminiowych

Cybulko Piotr, Węgrzyn Tomasz, Szczucka-Lasota Bożena, Krzysztoforski Michał, Döring Adam

Wiadomości Elektrotechniczne

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2022

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R. 90, nr 9

28--30

PL

Systemy dystrybucji energii elektrycznej oparte na szynoprzewodach znajdują zastosowanie m.in. w obiektach przemysłowych wykorzystujących instalacje elektryczne o różnych mocach. Wymagania dotyczące zasilania są realizowane przy użyciu różnych grup szynoprzewodów. Rodzaj używanych połączeń toru prądowego w szynoprzewodach wpływa na przewodność elektryczną połączeń i określa warunki, w jakich można korzystać z szynoprzewodów. W tym artykule przedstawiono wpływ typu procesu spawania złączy w szynoprzewodach aluminiowych pod kątem ich przewodności elektrycznej.

EN

Electricity distribution systems based on busducts are used, among others, in industrial facilities using electrical installations with different capacities. The power requirements are realised by using different groups of busducts. The type of current path connections used in busducts influences the electrical conductivity of the connections and determines the conditions under which busduckts can be used. In this paper, the influence of the type of welding process for joints in aluminium busducts on their electrical conductivity is analysed.

5

Organiczna warstwa transportująca ładunki dodatnie w polimerowych i perowskitowych ogniwach słonecznych – wybrane aspekty materiałowe i techniczne

Iwan Agnieszka, Bogdanowicz Krzysztof A., Przybył Wojciech

Przegląd Elektrotechniczny

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2022

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R. 98, nr 9

178--181

PL

W artykule omówiono wpływ organicznej warstwy transportującej ładunki dodatnie (HTM) na parametry elektrochemiczne i elektryczne polimerowych i perowskitowych ogniw słonecznych. W oparciu o badania własne przeanalizowano wpływ budowy chemicznej polimerów czy związków małocząsteczkowych stosowanych jako HTM na sprawność ogniw słonecznych trzeciej generacji. Najwyższą sprawność otrzymano dla ogniw perowskitowych na bazie iminy (PCE = 14,4%), zaś najwyższą wartość przewodnictwa dla PEDOT:PSS w roztworze wodnym (1,03 × 10-3 S/cm).

EN

The article discusses the influence of the organic hole layer (HTM) on the electrochemical and electrical parameters of polymer and perovskite solar cells. Based on our own research, the influence of the chemical structure of polymers or low molecular weight compounds used as HTM on the efficiency of third generation solar cells was analyzed. The highest efficiency was obtained for imine-based perovskite cells (PCE = 14.4%) and the highest conductivity value for PEDOT:PSS in aqueous solution (1.03 × 10-3 S/cm).

6

Charakteryzacja wielokanałowego transportu nośników ładunku dla epitaksjalnych struktur półprzewodnikowych

Wróbel Jarosław, Złotnik Sebastian, Boguski Jacek, Kojdecki Marek, Wróbel Jerzy

Przegląd Elektrotechniczny

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2022

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R. 98, nr 9

228--230

PL

W pracy zwrócono uwagę na potrzebę rozwoju technik do precyzyjnego parametryzowania wielokanałowego transportu nośników ładunku, mających fundamentalne znaczenie dla efektywnego projektowania przyrządów półprzewodnikowych. Przedstawiono aktualny stan rozwoju tych technik pomiarowych w Wojskowej Akademii Technicznej, oraz przykładowe rezultaty dla struktur półprzewodnikowych, otrzymywanych techniką epitaksji z wiązek molekularnych (MBE).

EN

The paper highlights the need to develop techniques for the precise parameterization of multi-channel charge carrier transport, which are of fundamental importance for the effective design of semiconductor devices. The current state of development of these measurement techniques at the Military University of Technology is presented, as well as exemplary results for semiconductor structures obtained by molecular beam epitaxy (MBE).

7

Mathematical simulation of a microelectronic transducer with frequency output for measuring the induction of the magnetic field

Osadchuk Alexander. V., Osadchuk Iaroslav A., Martyniuk Volodymyr V., Krylik Lyudmila. V., Evseeva Maria V.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2022

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T. 12, nr 2

43--49

EN

A new magnetically sensitive element based on the synthesized semiconductor material has been developed. A method for the synthesis of a complex compound has been developed tetrakis-μ3-(methoxo) (methanol)-pentakis (acetylacetonate) (tricuprum (II), neodymium (III)) methanol (I). Conducted properties have been studied complex compound in compressed form in the temperature range 273 - 493 K. In the developed magnetoresistor when changing the induction of the magnetic field from 10-3 to 200 mT, the resistivity varies from 3.12∙10-5 Ohm to 1.25∙10-2 Ohm∙m. On the basis of the developed magnetically sensitive resistive element the circuit solution of the frequency transducer of a magnetic field is offered. The frequency transducer of the magnetic field is a hybrid integrated circuit consisting of a bipolar transistor and a gate transistor. The frequency of generation of the developed transducer increases the most in the range from 10-3 T to 0.2 T, and at a supply voltage of 5.0 V varies from 250 kHz to 600 kHz, and in the whole range of changes in magnetic field induction varies from 250 kHz to 750 kHz. The sensitivity of the developed device with frequency output for measuring the induction of the magnetic field is from 400 Hz/mT to 800 Hz/mT.

PL

Opracowano nowy element czuły magnetycznie oparty na zsyntetyzowanym materiale półprzewodnikowym. Opracowano metodę syntezy związku złożonego tetrakis-μ3-(methoxo)(metanol)-pentakis(acetyloacetonian)(tricuprum (II), neodym (III)) metanol (I). Badano właściwości przewodzące związku złożonego w postaci sprasowanej, w zakresie temperatur 273–493 K. W opracowanym magnetooporniku przy zmianie indukcji pola magnetycznego od 10-3 do 200 mT rezystywność zmienia się od 3,12∙10-5 Ohm do 1,25∙10-2 Ohm∙m. Na podstawie opracowanego magnetycznie czułego elementu rezystancyjnego zaproponowano rozwiązanie układu przetwornika pola magnetycznego na częstotliwość. Przetwornik ten jest hybrydowym układem scalonym składającym się z tranzystora bipolarnego i tranzystora bramkowego. Częstotliwość generacji opracowanego przetwornika wzrasta najbardziej w zakresie od 10-3 T do 0,2 T i przy napięciu zasilania 5,0 V zmienia się od 250 kHz do 600 kHz, zaś w całym zakresie zmian indukcji pola magnetycznego zmienia się od 250 kHz do 750 kHz. Czułość opracowanego urządzenia z wyjściem częstotliwościowym do pomiaru indukcji pola magnetycznego wynosi od 400 Hz/mT do 800 Hz/mT.

8

Wpływ procesu aktywacji na właściwości bentonitów

Ryłko Kinga, Skorupa Natalia, Sobczyk Natalia, Lenar Nikola

Analit

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2022

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Nr 12

36--48

PL

Bentonit, pod względem geologicznym, zaliczany od jest do skał pochodzenia wulkanicznego. Jest to ił wykazujący silne pęcznienie oraz cechujący się unikalnymi właściwościami fizycznymi. Parametry te wynikają z wysokiej zawartości montmorylonitu (minerał ilasty należący do grupy smektytu). Podczas aktywacji zachodzi proces kontrolowanej wymiany jonów. Wspomniane jony wapnia, znajdujące się początkowo w międzypakietowej przestrzeni montmorylonitu, zastępowane są jonami sodu, które wprowadza się z aktywatorem. Proces aktywacji bentonitu powoduje polepszenie jego właściwości - zwiększoną zdolność pęcznienia czy też podwyższoną zdolność wiązania. W niniejszym artykule skupiono się na zbadaniu podstawowych właściwości bentonitów oraz ich zmiany pod wpływem procesu aktywacji. Badania pH, przeprowadzone przy użyciu elektrody szklanej, wykazały, że stężenia jonów wodorowych były znacznie wyższe i stabilniejsze w czasie w przypadku bentonitu aktywowanego. Na podstawie otrzymanych wyników przewodnictwa mierzonego metodą konduktometrii można zaobserwować wzrost jego wartości wraz z upływem czasu. Tendencja ta była obserwowalna w przypadkach obu bentonitów, z tą różnicą, że wartości przewodnictwa bentonitu aktywowanego przyjmowały kilkukrotnie wyższe wartości w porównaniu z tym niepoddanym aktywacji. Analiza otrzymanych wartości wykazała, że bentonit aktywowany pęczniał 4-krotnie bardziej niż ten nieaktywowany. Zarówno współczynnik pęcznienia, jak i zawartość wody wyznaczone zostały eksperymentalnie. Po usunięciu, w procesie suszenia, wody adsorpcyjnej oraz międzypakietowej, bentonit aktywowany zawierał dwa razy mniej wody niż ten niepoddany aktywacji węglanem sodu.

EN

Bentonite is classified as a rock of volcanic origin. It is a clay that shows strong swelling and has unique physical properties. These parameters are caused by the high content of montmorillonite (a clay mineral belonging to the smectite group). During activation, a process of controlled ion exchange takes place. The calcium ions, initially located in the inter-pack space of montmorillonite, are replaced by sodium ions with activator. The activation process of bentonite results in an improvement of its properties - increased swelling capacity or binding capacity. This article focuses on the examination of the basic properties of bentonites and their changes under the effect of the activation process. Studies of pH, conducted using a glass electrode, showed that the concentration of hydrogen ions was much higher and more stable over time for the activated bentonite. The results obtained after conductometric measurements show the incensement of conductivity with time. This trend was visible in the cases of both bentonites, with the difference that the conductivity values of the activated bentonite assumed significantly higher compared to values obtained to inactivated one. Analysis of the obtained values showed that the activated bentonite swelled 4 times more the inactivated one. Values of swelling coefficient and water content were determined experimentally. After removal of adsorption and inter-pack water (during the drying process), the activated bentonite contained twice less water than the one not activated by adding sodium carbonate.

9

The Potential of Sisal Fibre as an Additive in Lightweight Foamed Concrete for Thermal Properties Enhancement

Mydin Md Azree Othuman

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 3

89--97

EN

Lightweight foamed concrete (LFC) is extremely permeable, and its thermal properties reduce with rising in the number of voids. In turn, to improve its thermal properties, the solid matrix of LFC can be adjusted by incorporating several natural fibers. The influence of sisal fiber in LFC was not investigated before in the current body of knowledge. Hence, there is some ambiguity considering the mechanism by which and the extent to which the sisal fiber can influence LFC thermal properties. Hence, this study concentrates on distinguishing the potential use of sisal fiber in LFC. The purpose of this research is to determine LFC's thermal characteristics when sisal fiber is added. Casting and testing of densities of 800 kg/m3 and 1600 kg/m3 were done. Various weight fractions were employed pertaining to sisal fiber, i.e., 0.15%, 0.30%, 0.45% and 0.60%. The components of thermal properties, which consist of specific heat, thermal conductivity as well as thermal diffusivity were evaluated. To get comparable results, we fixed the water to cement ratio as 0.45 while keeping constant the cement to sand ratio at 1:1.5. It was seen that optimum results were achieved with the addition of 0.45% of sisal fiber with regard to all the thermal characteristics regarded in this exploration. At 0.45% weight fraction about sisal fiber, maximum compaction was achieved with fibers as well as the cementitious matrix, which ensued in good mix uniformity. Beyond the optimum level pertaining to the presence of sisal fiber, it could be seen that fibers would agglomerate and exhibit non-uniform dispersion, which resulted in a decline with regards to the entire thermal characteristics assessed.

10

An experimental study on the complex resistivity of fractured rock under different saturation conditions

Pan Baozhi, Ruhan A., Guo Yuhang, Zhang Lihua, Wei Boyang, Zhou Weiyi

Acta Geophysica

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2022

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Vol. 70, no 3

1061--1081

EN

The fracture can be a good channel for oil and gas migration, which has a great influence on the permeability of the reservoir. Therefore, it is of major significance to identify fractures and determine the characterization parameters and physical proper ties of fractured reservoirs. In this study, homogeneous sandstone was used to simulate different artificially fractured rocks. The fractured rock samples had different fracture widths, fracture numbers, and fracture dip angles. In addition, the complex impedance and weights of the rock samples were measured during the process of natural evaporation, and the relationships between the water saturation and the complex resistivity values at different frequencies were examined. The frequency range is 100 Hz–10 kHz. It was found that the influence effects of frequency on the resistivity, dielectric constant, and loss factor had differed among the homogeneous samples and the fractured rock sample. The fracturing had led to the resistivity index and the water saturation curves separating under the different frequencies, and the degree of the dielectric constant index and water saturation curve separation became larger. Furthermore, the influencing effects of the fracture widths, fracture numbers, and fracture dip angles mainly occurred in terms of three aspects. The first was the slope of the resistivity index and water saturation curves (IR–Sw). The second was the slope of the dielectric constant index and water saturation curves (Iε–Sw), and the third was the loss tangent D and water saturation Sw curves.

11

Analysis of a Method for Measuring Deposit Impedance Parameters Using Charge Amplifier and Lock-in Voltmeter

Wiśniewski Dariusz R.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2021

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nr 24(1)

67--81

EN

Methods for measuring deposit parameters are often based on a capacitance or conductivity measurement aimed at estimating, e.g. deposit moisture content. In practice, these methods fail for materials with a low degree of homogeneity, a diverse porous structure or high conductivity, e.g. due to a high water content. This article demonstrates an approach that enables a more precise estimation of the parameters of any deposit. The presented method involves the use of a measuring system in a charge amplifier configuration and the application of a technique using lock-in detection or a lock-in voltmeter to determine resistance and capacitance parameters of a deposit based on signals received from the measuring system. This method can be successfully used wherever the test deposit material is highly heterogeneous and contains both dielectric and conductive materials. The article presents an example of a solution to a measuring system using two planar electrodes that can be dimensioned depending on the deposit dimensions. It is followed by a presentation of a method for converting the signal from the measuring system into impedance parameters of the deposit using a lock-in voltmeter. The analysis of the operation of the entire measuring system was modelled in Matlab/Simulink, and the operation results were presented.

12

Applying Electrical Impedance Tomography Techniques for Detection of Decay Inside Trees

Kieu Duy Thong, Vu Hong Duong, Nguyen Thi Thu Hang, Nguyen Thu Thuy

Inżynieria Mineralna

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2021

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no. 2

31--40

EN

Trees play a critical role in creating green spaces in public areas such as streets, parks, schools, offices. Over time, the trees often get pests and diseases, and then rotten trees can break. To care for and conserve the trees, it is necessary to determine the condition inside the trunk, especially the possibility of having a hollow or not. Wood decay, modifications of moisture and ion content, density due to biotic and abiotic stress agents of water extremity, salinity, and infection strongly change (di-) electrical properties of wood. Hence, we propose to use electrical impedance tomography to detect the change in electrical properties inside the trees that can link to wood decay. In electrical impedance tomography, an array of electrodes is attached around the tree trunk, and small alternating currents are injected via these electrodes, so the resulting voltages are measured. Processing the data, we can construct the spatial distribution of impedance (or resistivity) of the object. In this work, we will present the preliminary results of our group research. We will show theoretical forward modeling results, followed by laboratory experiments and real data application. The results illustrate that electrical impedance tomography can be useful to define several decay scenarios inside the trees.

13

Frequency domain electromagnetic and electrical resistivity geophysical investigation of tar sands deposits in the Ijebu Waterside area, Eastern Dahomey Basin, southwestern Nigeria

Osinowo Olawale Olakunle, Okechukwu Ifeayinchukwu

Geology, Geophysics and Environment

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2021

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Vol. 47, no. 4

217--226

EN

The use of electromagnetic conductivity and electrical resistivity geophysical techniques has been employed in this study to investigate the occurrence, thickness, and spatial distribution of bitumen deposit around Makun-Omi in the Ijebu Waterside area of southwestern Nigeria. Subsurface apparent conductivity distribution data obtained using Geonic 34-3 equipment along fifteen traverses which sounded from different depths of 7.5, 15, 30 and 60 m at inter-coil separation of 10, 20 and 40 m in vertical and horizontal coupling modes and ground resistivity distribution measurements, obtained using Geopulse Tiger Allied resistivity meter at fourteen Vertical Electrical Sounding (VES) stations, were processed and employed to characterize the subsurface in terms of tar sands distribution. The conductivity and resistivity distribution in the form of a 3D earth model, iso-depth maps, 2D sections generated from the processed conductivity and resistivity data indicate relatively low conductivity <20 mS/m and high resistivity >1300 Ωm values around tar/bitumen impregnated sands which mostly occurred in the southern part of the study area. Clearly defined conductivity and resistivity anomalies which delineate the lateral and vertical occurrence of tar impregnated sands underscore the efficacy of integrating electromagnetic and electrical resistivity geophysical techniques to identify occurrence of economic deposits of tar sands in parts of southwestern Nigeria.

14

Selected Quality Indicators of Surface Waters of the Czestochowa City and Neighbouring Municipalities

Kończyk Joanna

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 1

100--108

EN

The surface water quality significantly affects the purity level of groundwater drawn for the municipal purposes. The pollution presence in surface waters is fundamentally the effect of the anthropogenic activity in a particular area while the type and volume of pollution depend closely on the intensity of any such activity. The paper presents the results of types of selected quality indicators of surface waters, i.e. pH, electrical conductivity and heavy metal concentration: Fe, Mn, Zn, Cu, Cd, Ni, Pb and Cr in the surface waters collected from the city of Czestochowa and neighbouring municipalities – the locations of water intakes and deep wells operated by the Water Supply and Sewerage Joint Stock Company of the Czestochowa District in order to provide the citizens with potable water. The findings of analyses of water collected every month in the period from January to September 2020 in 9 points were the basis for an observation of a time and space variability of the values of the quality parameters studied, which is evident of a diversified impact of the surroundings on water environment in consecutive research months. The potential water pollution sources were also indicated.

15

Fabrication of a Novel Silver-Based Electrical Contact Composites and Assessment of Its Mechanical and Electrical Properties

Kumar Praveen S., Senthil S. M., Parameshwaran Rathinasamy, Rathanasamy Rajasekar

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 4

1087--1094

EN

The electrical contactors play a crucial role in closing the circuit in many power distribution components like overhead lines, underground cables, circuit breakers, transformers, and control systems. The failure in these components mainly occurs due to the break-down of contactors due to the continuous opening and closing action of contacts. Silver (Ag)-based oxide contact materials are widely used in practice, among which silver tin oxide (AgSnO2) is most common. An attempt is made in increasing the performance of AgSnO2, by adding Tungsten Oxide (WO3) in various weight proportions, thus finding the optimal proportion of AgSnO2WO3 to have increased mechanical and electrical performances. All the composite samples are fabricated in-house using powder metallurgy process. The assessment of physical and electrical properties namely, density, hardness, porosity, and electrical conductivity, showed that 90%Ag-8.5%SnO2-1.5%WO3 composite yielded superior results. With help of morphological tests, wear characteristics are also investigated, which showed that 90%Ag-8.5%SnO2-1.5%WO2 composite has a wear coefficient of 0.000227 and a coefficient of friction of 0.174 at an optimized load of 10 N and sliding velocity of 0.5 mm/s.

16

Wykorzystanie metody konduktometrycznej i georadarowej do identyfikacji stopnia ugniecenia wierzchniej warstwy gruntu

Akinsunmade Akinniyi, Tomecka-Suchoń Sylwia, Pysz Paweł, Karczewski Jacek, Juliszewski Tadeusz, Zagórda Mirosław, Kiełbasa Paweł

Przegląd Elektrotechniczny

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2020

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R. 96, nr 2

137--141

PL

W artykule przedstawiono relacje między stopniem zagęszczenia gruntu określonym penetrometrem stożkowym, przewodnością elektryczną gruntu na wybranych głębokościach jego profilu określoną konduktometrem oraz echogramem wykonanym georadarem. Badania przeprowadzono w warunkach rzeczywistych a do zagęszczania gruntu wykorzystano ciągnik rolniczy wyposażony w standardowe opony. Zidentyfikowano istotną zbieżność wyników pomiarów dla wszystkich metod pomiarowych, która pozwala stosować je wymiennie do identyfikacji nadmiernego zagęszczenia gruntu np. śladów przejazdu maszyn a także innych anomalii w zagęszczeniu gruntu pod warunkiem istnienia wyrównanych parametrów wilgotnościowych mierzonego ośrodka.

EN

The article presents the relationship between the degree of soil compaction determined by a cone penetrometer and soil electrical conductivity at selected depths of its profile determined by a conductometer and a GPR echogram. The tests were carried out in real conditions and an agricultural tractor equipped with standard tires was used for soil compaction. Significant convergence of measurement results was identified for all measurement methods, which allows them to be used interchangeably to identify excessive soil compaction, e.g. machine tracks, as well as other anomalies in soil compaction, provided that the humidity parameters of the measured medium are equal.

17

The use of chemically modified PVC waste to remove ions from wastewater

Ouerghui Abid, Ammari Faycel, Girard Christian

Polimery

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2020

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T. 65, nr 11-12

801--806

EN

Purified (in acetone, at 50° C for 72 h), post-consumer PVC waste was grafted with 1,4-benzodioxane6-amine and 2-aminobenzimidazole to increase its ability to remove ions from wastewater (from the Beja region, Tunisia). The PVC waste was characterized by IR spectroscopy, differential thermal analysis (DTA) and elemental nitrogen analysis. The ability of modified PVC waste to remove ions [sulphates ions (SO4 2-), nitrates ions (NO3 -), chloride ions (Cl-), carbonates ions (CO3 -), metal ions (Mg2+, Zn2+, Na+, K+…)] from wastewater was assessed based on ion conductivity measurements. It was found that modified PVC waste shows a greater efficiency in the removal of ions from wastewater than unmodified waste.

PL

Oczyszczone (w acetonie, w temp. 50°C przez 72 h), poużytkowe odpady PVC szczepiono 1,4-benzodioksano-6-aminą i 2-aminobenzimidazolem w celu zwiększenia ich zdolności do usuwania jonów (SO4 2-, NO3 -, Cl-, CO3 -, Mg2+, Zn2+, Na+, K+…) z wód ściekowych (z regionu Beja, Tunezja). Odpady PVC scharakteryzowano za pomocą spektroskopii IR, różnicowej analizy termicznej (DTA) i analizy elementarnej azotu. Zdolność odpadów PVC do usuwania jonów znajdujących się w wodach ściekowych oceniono na podstawie pomiarów przewodnictwa jonowego. Stwierdzono, że modyfikowane odpady PVC wykazują większą skuteczność usuwania jonów znajdujących się w ściekach niż odpady niemodyfikowane.

18

Electrical properties of sugar palm nanocrystalline cellulose reinforced sugar palm starch nanocomposites

Hazrol M. D., Sapuan S. M., Ilyas R. A., Othman M. L., Sherwani S. F. K.

Polimery

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2020

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T. 65, nr 5

363--372

EN

In this study, the effect of sugar palm nanocrystalline cellulose (SPNCC) loading (0.00–0.10 wt %) on the electrical resistance, resistivity, and conductivity of SPS/SPNCC (SPS – sugar palm starch) nanocomposite films were evaluated. The experiments were conducted using the four-probe method and Ohm’s law, resistivity and conductivity equations were utilized to obtain the electrical properties. The results revealed that the resistivity values of SPS/SPNCC films were found to be in the range of 3.1 · 102 to 1.5 · 104 (Ω · cm).

PL

Oceniono wpływ dodatku nanokrystalicznej celulozy otrzymanej z palmy cukrowej (SPNCC) (0,00–0,10% mas.) na rezystancję elektryczną, rezystywność i przewodnictwo folii wytworzonych z nanokompozytów (SPS/SPNCC) na bazie skrobi z palmy cukrowej (SPS). Badania przeprowadzono metodą czterosondową z zastosowaniem prawa Ohma; właściwości elektryczne określono na podstawie równań rezystywności i przewodności. Stwierdzono, że wartość rezystywności folii SPS/SPNCC mieści się w zakresie konduktywności od 3,1 · 102 do 1,5 · 104 (Ω · cm).

19

Enhancement of electrical performance of ZnSe thin films via Au nanosandwiching

Qasrawi A. F., Taleb Maram F.

Materials Science Poland

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2020

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Vol. 38, No. 1

174--180

EN

In this work, we report the effect of sandwiching of Au nanosheets on the structural and electrical properties of ZnSe thin films. The ZnSe films which are grown by the thermal evaporation technique onto glass and yttrium thin film substrates exhibit lattice deformation accompanied with lattice constant extension, grain size reduction and increased defect density upon Au nanosandwiching. The temperature dependent direct current conductivity analysis has shown that the 70 nm thick Au layers successfully increased the electrical conductivity by three orders of magnitude without causing degeneracy. On the other hand, the alternating current conductivity studies in the frequency domain of 10 MHz to 1800 MHz have shown that the alternating current conduction in ZnSe is dominated by both of quantum mechanical tunneling and correlated barrier hopping of electrons over the energy barriers formed at the grain boundaries. The Au nanosheets are observed to increase the density of localized states near Fermi level and reduce the average hopping energy by ~5 times. The conductivity, capacitance, impedance and reflection coefficient spectral analyses have shown that the nanosandwiching of Au between two layers of ZnSe makes the zinc selenide more appropriate for electronic applications and for applications which need microwave cavities.

20

Procedury kalibracji i synchronizacji czujników oraz aparatury sterująco-pomiarowej w modelach fizycznych reaktorów metalurgicznych

Pieprzyca Jacek, Merder Tomasz

Hutnik, Wiadomości Hutnicze

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2020

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Vol. 87, nr 9

217--220

PL

Modelowanie fizyczne, jako technika badawcza zjawisk występujących w trakcie procesów przemysłowych, często rozumiane jest jako prowadzenie eksperymentów z wykorzystaniem modeli fizycznych urządzeń, w których te zjawiska zachodzą. Takie rozumowanie jest błędne. Modelowanie to proces składający się z wielu etapów, zarówno czysto abstrakcyjnych (koncepcyjnych), jak i technicznych. Proces modelowania rozpoczyna się w momencie podjęcia decyzji o jego zastosowaniu, a kończy wraz z uzyskaniem zadowalających rezultatów. Jednym z ważniejszych etapów procesu modelowania jest wybór adekwatnej do badań i stosowanych rodzajów znacznika aparatury pomiarowej, a w szczególności czujników pomiarowych. Ich synchronizacja i rzetelna kalibracja mają fundamentalny wpływ na jakość i rzetelność uzyskiwanych wyników badań. W artykule przedstawiono sposób realizacji tego etapu procesu modelowania, posługując się przykładem fizycznego modelu wodnego stanowiska pieca kadziowego.

EN

Physical modelling - a research technique for studying the phenomena occurring during industrial processes - is often only perceived as conducting experiments using physical models of devices in which these phenomena occur. Such perceptions are wrong though. Physical modelling is a process consisting of many stages, some purely abstract (conceptual) and some technical. The process commences by setting clear assumptions of its application; and concludes once these assumptions are met. An important stage of the modelling process is the careful selection of measuring equipment, in particular measuring sensors. The sensors’ synchronisation and precise calibration have a fundamental impact on the quality of the final results. This article presents a method of implementing the measuring sensors in the modelling process, using the example of a physical water model of a ladle furnace.