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Wyszukujesz frazę "Zero, M." wg kryterium: Wszystkie pola


Tytuł:
Control of open-end induction motor by multi-objective GA based selective harmonic elimination PWM to reduce zero sequence currents and torque ripples
Autorzy:
Kumar, K. Kalyan
Anuradha, K.
Suryakalvathi, M.
Powiązania:
https://bibliotekanauki.pl/articles/41179745.pdf
Data publikacji:
2023
Wydawca:
Politechnika Warszawska, Instytut Techniki Cieplnej
Tematy:
open-end winding induction machine
zero sequence currents
torque ripple
selective harmonic elimination
triplen harmonics
maszyna indukcyjna
uzwojenie otwarte
tętnienie momentu obrotowego
selektywna eliminacja harmonicznych
potrójne harmoniczne
Opis:
A double inverter powered induction motor with open stator winding has few benefits, including excessive error forbearance functionality, great flexibility and lesser rating of DC input voltage etc. For this Configuration, two types of Modules can be implemented: they are Non-Isolated DC link and Isolated DC link. In these two, Non-Isolated DC link is a good choice due to effective DC-link utilization and ruggedness, which is very beneficial in many applications. However, this module produces more zero sequence currents (Z-SC) by means of common mode (CMMD) voltage, which flows through DC bus. The circulation of Z-SC must be as little as possible since it merely rises the amplitude of currents in all phases. High ripple frequency of currents and torque, in addition results in extra loss, which not only reduces the efficiency, but influences loading ability and quickens the aging of drive. The Triplen harmonics can be defined as harmonics with integer of three times the frequency at fundamental, when they are in Phase in all Phases forms the Z-SC. In this paper, a novel SHE method is chosen to target Triplen harmonics in Single DC Source Module (Non- Isolated) and holding preferred fundamental quantity, which aids in improving the torque handling ability of the motor. In addition, the investigation of dual inverter fed OEW-IM with both common DC source as well as separate DC sources is also explored in the SHE for different number of switching angles and variable Modulation Index (MI) towards the torque ripples and Z-SC reduction given. The foremost challenge related to the SHE method is resolving a set of higher order nonlinear equations with a number of variables. A Multi-objective GA method is provided for that challenge which effects the reduction in Z-SC so that torque ripples will be minimized. Moreover, the novel SHE method reduces the number of harmonics better than the conventional SHE, which further decreases TH-D with decent fundamental quantity. For validation, the essential mathematical formulations and simulation results are presented.
Źródło:
Journal of Power Technologies; 2023, 103, 1; 72-87
1425-1353
Pojawia się w:
Journal of Power Technologies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Vehicular S-LSTM NOMA Over Time Selective Nakagami-m Fading with Imperfect CSI
Autorzy:
Shankar, Ravi
Chaudhary, Bhanu Pratap
Mishra, Ritesh Kumar
Powiązania:
https://bibliotekanauki.pl/articles/2174454.pdf
Data publikacji:
2022
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
inter-symbol interference
MIMO
NOMA
orthogonal frequency division multiplexing
OFDM
S-LSTM
zero-mean circularly symmetric complex Gaussian
ZM-CSCG
Opis:
In this paper, the performance of a deep learningbased multiple-input multiple-output (MIMO) non-orthogonal multiple access (NOMA) system is investigated for 5G radio communication networks. We consider independent and identically distributed (i.i.d.) Nakagami-m fading links to prove that when using MIMO with the NOMA system, the outage probability (OP) and end-to-end symbol error rate (SER) improve, even in the presence of imperfect channel state information (CSI) and successive interference cancellation (SIC) errors. Furthermore, the stacked long short-term memory (S-LSTM) algorithm is employed to improve the system’s performance, even under time-selective channel conditions and in the presence of terminal’s mobility. For vehicular NOMA networks, OP, SER, and ergodic sum rate have been formulated. Simulations show that an S-LSTM-based DL-NOMA receiver outperforms least square (LS) and minimum mean square error (MMSE) receivers. Furthermore, it has been discovered that the performance of the end-to-end system degrades with the growing amount of node mobility, or if CSI knowledge remains poor. Simulated curves are in close agreement with the analytical results.
Źródło:
Journal of Telecommunications and Information Technology; 2022, 4; 47--59
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of CSRZ and CSNRZ Coding for DQPSK and OQPSK Transmitter Configurations for Optical Microwave Generation Signals Based on Stimulated Brillouin Scattering
Autorzy:
Cherutoi, H. C.
Waswa, D. W.
Muguro, K. M.
Choge, D. K.
Powiązania:
https://bibliotekanauki.pl/articles/1031437.pdf
Data publikacji:
2021
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Carrier Suppressed Non-Return to Zero
Carrier Suppressed Return to Zero
Dense Wavelength Division Multiplexing
Differential Quadrature Phase Shift Keying
Offset Quadrature Phase Shift Keying
Stimulated Brillouin Scatteriring
Opis:
The use of Carrier Suppressed Non-Return to Zero (CSNRZ) and Carrier Suppressed Return to Zero (CSRZ) modulation formats in Dense Wavelength Division Multiplexing (DWDM) channels at 1 Gb/s and 10 Gb/s is investigated. The results of simulated analysis using Differential Quadrature Phase Shift Keying (DQPSK) and Offset Quadrature Phase Shift Keying (OQPSK) formats are presented. We demonstrate that Stimulated Brillouin Scatteriring (SBS) is a major contribution of the back-scattering signal. At bit rate of 1 Gb/s and 10 Gb/s, CSRZ-OQPSK modulation format has a low threshold for SBS signal generation. For a data rate of 1 Gb/s, high SBS threshold of 19.76 dBm for CSRZ-DQPSK is recorded. The results can be used to suppress SBS in high power lasers which could be useful in high bit rate signal transmission.
Źródło:
World Scientific News; 2021, 152; 27-38
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the harmonic composition of current in the zero-working wire at the input of the load node with the prevailing non-linear power consumers
Autorzy:
Yudaev, Igor V.
Rud, Evgeny V.
Yundin, Mikhail A.
Ponomarenko, Tamara Z.
Isupowa, Aleksandra M.
Powiązania:
https://bibliotekanauki.pl/articles/1841306.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
harmonic currents
non-linear power receiver
non-symmetry
three-phase fourwire network
zero working wire of the network
prądy harmoniczne
nieliniowy odbiornik mocy
niesymetria
sieć trójfazowa czteroprzewodowa
zerowy przewód roboczy sieci
Opis:
Due to the extensive use of nonlinear power consumers, there is currently an urgent problem of high harmonic content in power supply networks. The paper provides experimental investigations and a study of the nature of the change in the main harmonic components of the current in the neutral working wire of a three-phase four-wire network with a voltage of 0.38 kV. The purpose of this study is to compare the load readings on the amplitude-phase-frequency characteristics of the current in the neutral working wire of the 0.38 kV network with the linear and non-linear load. To study the effect of load changes on the amplitude-phase-frequency characteristics of currents in the linear and zero working wires at the input of the load node, measurements were carried out by certified electrical measuring instruments. The analysis of the results obtained for the load node whose power was formed mainly by a lighting system with fluorescent and LED lamps and a system of office electrical receivers (computers, copiers, printers, scanners, etc.) was performed. It can be concluded that a current comparable to the currents of the linear wires of the network flows from the load node with the predominant nonlinear power receivers through the zero-working wire. At the same time, in the zero-working wire of the network, the third harmonic currents prevail over the main frequency currents.
Źródło:
Archives of Electrical Engineering; 2021, 70, 2; 463-473
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mitsubishi A6M Zero nad Południowym Pacyfikiem. Cz. 2, Styczeń-lipiec 1943 roku
Autorzy:
Zalewski, Krzysztof (1966-2012).
Powiązania:
Lotnictwo 2021, nr 1, s. 86-98
Data publikacji:
2021
Tematy:
II wojna światowa (1939-1945)
Siły powietrzne
Wojna powietrzna
Samoloty bojowe
Samoloty myśliwskie
Mitsubishi A6M Reisen Zero (samolot)
Operacje powietrzne
Artykuł z czasopisma fachowego
Opis:
Artykuł przedstawia operacje i walki powietrzne, w których uczestniczyły japońskie i amerykańskie siły powietrzne w okresie styczeń-lipiec 1943 roku. Autor skoncentrował się na przedstawieniu sytuacji i działań Japończyków, w szczególności operacji, w których uczestniczyły samoloty myśliwskie Mitsubishi A6M Reisen (zwane także Zero). Przedstawił stan japońskiej floty po nieudanym dla Japończyków zakończeniu operacji „I-go” (trwającej między 1 a 16 kwietnia) oraz kolejne operacje w okresie od maja do sierpnia 1943, w których toku Japończycy przeszli już głównie do defensywy. Opisał m.in. amerykański desant na wyspę Rendova z 30 czerwca, a także wszystkie jednostki biorące udział w starciach oraz straty poniesione przez obie strony konfliktu. Omówił również inne operacje z udziałem ulepszonych już Mistubishi A6M3 nad Indiami Holenderskimi i Australią oraz przedstawiono pokrótce budowę, konstrukcje i ulepszenia wprowadzone do japońskich samolotów.
Fotografie.
Dostawca treści:
Bibliografia CBW
Artykuł
Tytuł:
Algorithm for solving the Discrete-Continuous Inspection Problem
Autorzy:
Grymin, R.
Bożejko, W.
Chaczko, Z.
Pempera, J.
Wodecki, M.
Powiązania:
https://bibliotekanauki.pl/articles/1403679.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
discrete-continuous optimization
UAV
VTOL
autonomous drone
zero emission
Opis:
The article introduces an innovative approch for the inspection challenge that represents a generalization of the classical Traveling Salesman Problem. Its priciple idea is to visit continuous areas (circles) in a way, that minimizes travelled distance. In practice, the problem can be defined as an issue of scheduling unmanned aerial vehicle which has discrete-continuous nature. In order to solve this problem the use of local search algorithms is proposed.
Źródło:
Archives of Control Sciences; 2020, 30, 4; 653-666
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Condition of circular economy in Poland
Stan gospodarki obiegu zamkniętego w Polsce
Autorzy:
Kledyński, Z.
Bogdan, A.
Jackiewicz-Rek, W.
Lelicińska-Serafin, K.
Machowska, A.
Manczarski, P.
Masłowska, D.
Rolewicz-Kalińska, A.
Rucińska, J.
Szczygielski, T.
Walczak, J.
Wojtkowska, M.
Zubrowska-Sudol, M.
Powiązania:
https://bibliotekanauki.pl/articles/231216.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
gospodarka obiegu zamkniętego
odpady komunalne
budownictwo
gospodarka ściekowa
zasoby pierwotne
energetyka węglowa bezodpadowa
produkt spalania uboczny
circular economy
municipal waste
construction
wastewater management
primary resources
zero-waste coal power
combustion by-product
Opis:
W niniejszym artykule przeglądowym przedstawiono stan gospodarki obiegu zamkniętego (GOZ) w Polsce. Pokazano GOZ w zróżnicowanym ujęciu: przedmiotowym (strumienie odpadów, energia), sektorowym (budownictwo, oczyszczalnie ścieków, energetyka węglowa) i zasobowym (minerały antropogeniczne, fosfor), a także pod kątem właściwego gospodarowania energią w budownictwie (budynki niemal-zero-energetyczne).
The manuscript presents the condition of circular economy in Poland in diversified approach: subjective (waste streams, energy), sectoral (construction, wastewater treatment, coal energy), related to the resources (phosphorous and anthropogenic minerals) and considering proper energy management (almost zero energy buildings). The achievements reached in different sectors as well as the requirements towards implementation of CE are presented. The advancement of recycling technologies does not deviate from the global level, in terms of areas specific to Poland. Limiting the exploitation of natural resources and usage of new materials as well as producing more durable products are of CE concern. Also energy and heat recovery in buildings and technological processes (e.g. during wastewater treatment), ways of utilization of combustion by-products and water decarbonization waste are described. The implementation of CE in Poland needs not only research and technical activities, but also the modification of technological processes, the right policy, overcoming crosssectoral barriers, developing legal regulations and support schemes for CE.
Źródło:
Archives of Civil Engineering; 2020, 66, 3; 37-80
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Maritime Green Solution for Traffic Congestion
Autorzy:
Petković, M.
Zubčić, M.
Krčum, M.
Vujović, I.
Powiązania:
https://bibliotekanauki.pl/articles/116659.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
marine traffic
traffic congestion
maritime green solution
zero emission transfer
port of split
green shipping
electric ship
electric catamaran
Opis:
Traffic congestion is a wide problem in many tourist destinations. Airports are usually distant from the city centers. Hence, road and rail traffic are widely used to connect airports and city centers. In this paper, we propose zero-emission solution for connection between airport and the center at the example of Croatian city Split. Since Split has become a popular tourist destination, the number of vehicles during summer season increases. As a measure to decrease air pollution, in this paper the marine traffic by electric vessels is proposed for the route Split – airport. Seven all-electrical vessels are presented with their technical characteristics. The idea is to have zero emission transfers by sea from the center of the Split to the airport. The criteria for minimum cruising speed is set to 13 knots, which ensures that one crossing takes 30 minutes and makes it competitive with other forms of transport.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2020, 14, 1; 97-103
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mitsubishi A6M Zero nad Południowym Pacyfikiem. Cz. 1, Styczeń-lipiec 1943 roku
Autorzy:
Zalewski, Krzysztof (1966-2012).
Powiązania:
Lotnictwo 2020, nr 12, s. 90-98
Data publikacji:
2020
Tematy:
II wojna światowa (1939-1945)
Siły powietrzne
Wojna powietrzna
Samoloty bojowe
Samoloty myśliwskie
Mitsubishi A6M Reisen Zero (samolot)
Artykuł z czasopisma fachowego
Opis:
Artykuł przedstawia operacje i walki powietrzne, w których uczestniczyły japońskie i amerykańskie siły powietrzne w okresie styczeń-lipiec 1943 roku. Autor skoncentrował się na przedstawieniu sytuacji i działań Japończyków, w szczególności operacji, w których uczestniczyły samoloty myśliwskie Mitsubishi A6M Reisen (zwane także Zero). Omówił stan japońskiej i amerykańskiej floty po wcześniejszych walkach na Wyspach Solomona (1942), zakończonych sukcesem sił amerykańskich. Opisał następnie amerykańską ofensywę, począwszy od stycznia 1943 roku na obszarze Nowa Brytania-Nowa Gwinea oraz japońskie operacje wojskowe: „Ke-go” (nazywana też Operacja Ke) – wycofanie sił japońskich z Guadalcanal, operację „I-go”, mającą na celu odzyskanie panowania w powietrzu przez Japonię i operację „Zemsta”, podczas której zginął admirał Japońskiej Cesarskiej Marynarki Wojennej, Isoroku Yamamoto.
Dostawca treści:
Bibliografia CBW
Artykuł
Tytuł:
Optimal selection of inner-branches parameters of matching circuits under the minimum branch-current RMS values and zero active-power conditions
Autorzy:
Jaraczewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/201906.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
multi-terminal-network compensators
optimization
nonlinear load
Opis:
The article is a continuation of a study on the synthesis of matching multi-terminal networks, also known as compensators. The reactive four-terminal-network compensators for linear loads were introduced in previous publications, but it appeared they operate effectively with nonlinear loads too. The methods to create a compensator for a mono-harmonic source, which allows complete independence of the input from output waveforms, ensuring optimal operating conditions for the source, are presented herein. The work for the first time presents the optimal four-terminal-network compensator applied to a nonlinear load.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2020, 68, 4; 777-783
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance evaluation of ZVS/ZCS high efficiency AC/DC converter for high power applications
Autorzy:
Ali, A.
Chuanwen, J.
Khan, M. M.
Habib, S.
Ali, Y.
Powiązania:
https://bibliotekanauki.pl/articles/200472.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
switching losses
zero current switching
zero voltage switching
power quality
reverse recovery loss
Opis:
The increased power density, reduced switching losses with minimum electromagnetic interference (EMI), and high efficiency are essential requirements of power converters. To achieve these characteristics, soft power converters employing soft switching techniques are indispensable. In this paper, a ZCS/ZVS PWM AC/DC converter topology has been emphasized, which finds applications in high power systems such as automobile battery charging and renewable energy systems. This converter scheme maintains zero current and zero voltage switching conditions at turn on and turn off moments of semiconductor switches, respectively and soft operation of rectifier diodes that lead to negligible switching and diode reverse recovery losses. Moreover, it improves power quality and presents high input power factor, low total harmonic distortion of the input current (THDI ) and improved efficiency. The validity of theoretical analysis of the proposed converter has been carried out experimentally on a 10 kW laboratory prototype. Experimental results prove that the soft switching operation of the semiconductor switches and diodes is maintained at 98.6% rated load efficiency. In addition, the performance evaluation has been performed by comparative analysis of the proposed converter with some prior art high power AC/DC converters. Efficiencies of the proposed and prior art high power topologies have been determined for different load conditions. The highest efficiency, power factor and lower THDI of the proposed converter topology complies with international standards.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2020, 68, 4; 793-807
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Code Family for QS-CDMA Visible Light Communication Systems
Autorzy:
Addad, M.
Djebbari, A.
Powiązania:
https://bibliotekanauki.pl/articles/308553.pdf
Data publikacji:
2018
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
CDMA
visible light communications
zero correlation zone
zero cross correlation
Opis:
Visible light communication (VLC) is a promising technology for wireless communication networks. Optical code division multiple access (OCDMA) is a strong candidate for VLC-based applications. The predominant source of bit error in OCDMA is the multiple access interference (MAI). To eliminate MAI in synchronous OCDMA, zero cross correlation (ZCC) codes have been proposed. However, synchronization problems and multipath propagation introduce relative non-zero time delays. Therefore, the zero correlation zone (ZCZ) concept was introduced. In this paper, we propose a new method for generating ZCC codes. The proposed construction can accommodate any number of users with flexible Hamming weight. The numerical results obtained show that the proposed codes significantly reduce MAI, compared to ZCC, as well as ZCZ codes.
Źródło:
Journal of Telecommunications and Information Technology; 2018, 3; 5-8
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An analysis of U.S. Custom and Border Protection’s tripartite Mexico border security policy
Autorzy:
Garrett, Terence M.
Powiązania:
https://bibliotekanauki.pl/articles/652819.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
security apparatus
migration
zero tolerance policy
panopticon
homo sacer
USA-Mexico border
Opis:
The Custom and Border Protection (CBP) border security policy was explicitly presented by former Acting Commissioner of CBP, David Aguilar, in testimony before the United States Senate Homeland Security and Governmental Affairs Committee (HSGAC) on April 4, 2017 in testimony on the subject of “Fencing Along the Southwest Border.” Important for discussion here are the key components of the DHS/CBP/Border Patrol’s strategy, or sets of policies, laying forth elements of the border walls (including barriers, fences), personnel, and technology in order to hinder, or intercept, undocumented migrants (homo sacer) from entering the United States illegally-all socially constructed. Aguilar notes in his opening remarks “Maintaining a safe and secure environment along the U.S.-Mexico border is critical. A safe and orderly border that is predicated on the strong rule of law deprives criminal organizations, drug cartels, and criminal individuals the opportunity to thrive.” In Aguilar’s testimony, when pressed by Ranking Member Senator Claire McCaskill, he set forth the current needs for CBP/Border Patrol priority of the three elements in the following order: (1) Technology (border surveillance), (2) Personnel (numbers of agents along the border), and, (3) The Border Wall (physical infrastructure: fences, walls, and vehicle barriers). The security apparatus affects dwellers along the Rio Grande and undocumented border crossers, demonstrated here with an analysis of the application of President Trump’s Zero Tolerance policy (April 6–June 20, 2018). The security framework applied in this paper will consist of theoretical approaches assessing border surveillance as a panopticon, the use of Border Patrol agents for apprehending, detaining and removing homo sacer, and the symbolism of the border wall as a spectacle and simulacrum-all understood in the pursuit of USA border security policy.
Źródło:
Annales. Etyka w Życiu Gospodarczym; 2018, 21, 4; 89-111
1899-2226
2353-4869
Pojawia się w:
Annales. Etyka w Życiu Gospodarczym
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative Analysis of Heating, Ventilation and Electricity Costs on the Example of Residential Building in the Near Zero-Energy Standard
Analiza porównawcza kosztów ogrzewania, wentylacji i energii elektrycznej na przykładzie budynku mieszkalnego w standardzie niemal zeroenergetycznym
Autorzy:
Krajewska, M.
Szopińska, K.
Powiązania:
https://bibliotekanauki.pl/articles/385421.pdf
Data publikacji:
2018
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
low-energy-consumption building
operating cost
natural gas
heat pump
photovoltaic system
budynek o niskim zużyciu energii
koszty eksploatacji
gaz ziemny
pompa ciepła
system fotowoltaiczny
Opis:
This article deals with an analysis of the operating costs of a building designed in the “near zero-energy” standard, with various technological solutions for heating and ventilation supported by a photovoltaic system (three technological variants). Following the analysis, a technological variant using an economic criterion based on the minimization of annual operating costs was selected.
W artykule przedstawiono analizę kosztów eksploatacji budynku projektowanego w standardzie “niemal zeroenergetycznym”, przy różnych wariantowych rozwiązaniach technologicznych ogrzewania i wentylacji wspomaganych systemem fotowoltaicznym (trzy warianty technologiczne). W następstwie przeprowadzonych analiz zarekomendowano wybór wariantu technologicznego przy zastosowaniu kryterium ekonomicznego opartego na minimalizacji rocznych kosztów eksploatacji.
Źródło:
Geomatics and Environmental Engineering; 2018, 12, 3; 55-64
1898-1135
Pojawia się w:
Geomatics and Environmental Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Copper extraction by wet chemical method
Autorzy:
Kugeria, P. M.
Mwangi, I.
Wachira, J.
Njoroge, P.
Powiązania:
https://bibliotekanauki.pl/articles/91906.pdf
Data publikacji:
2018
Wydawca:
Główny Instytut Górnictwa
Tematy:
hydrazones
in situ
reduction
zero valence
chicken dung
hydrazony
redukcja
wartościowość zerowa
nawóz kurzy
Opis:
In many countries large deposits of copper with no locally established copper based industries occur because known methods for extraction are prohibitively expensive and unaffordable. This study reports on an affordable and sustainable method for the extraction of copper. This was achieved through the use of a wet chemical method which makes use of hydrazones prepared in situ from chicken dung leached solution. The method involves the reduction of copper (II) ions leached from copper ore to zero valence using chlorine treated solution prepared from chicken droppings at a temperature range of 60-70 °C. The ore samples were pulverized to 250 micro millimetres and leached with hydrochloric acid to obtain leachate containing copper ions. The dissolved copper was reduced to copper metal and obtained by filtration. It was confirmed by XRFS analysis that, the metal purity was found to range between 60 and 80% depending on the ore used. In another experiment, chicken waste solution was used to extract copper from the ore. To the mixture, chlorine gas was then bubbledthrough a glass delivery tube to prepare the hydrazone in situ at a temperature range of 60-70 °C and a pure copper metal was obtained. The findings from this study have shown that there is great potential for the production of copper at low cost and this could be applied in both small-scale cottage industries and large industries using readily available resources such as chicken dung.
Źródło:
Journal of Sustainable Mining; 2018, 17, 4; 202-208
2300-1364
2300-3960
Pojawia się w:
Journal of Sustainable Mining
Dostawca treści:
Biblioteka Nauki
Artykuł

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