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1

Unmanned aerial vehicle – derived carbon stock estimation in cocoa agroforestry: Integrating red, green, blue imagery and modified allometric models for climate mitigation in smallholder landscapes of Indonesia

Jusrin Muhammad Justi Makmun, Dröge Saskia, Verbist Bruno, Prasetyo Lilik Budi, Setiawan Yudi

Ecological Engineering & Environmental Technology

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2025

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Vol. 26, iss. 7

285--298

EN

This study addresses methodological and contextual gaps in carbon stock estimation by developing a UAV-based model tailored for cocoa agroforestry systems in tropical smallholder landscapes. As nature-based solutions gain traction in climate change mitigation, reliable monitoring of agroforestry systems, marked by spatial heterogeneity and farmer-managed canopies, becomes increasingly vital. The research aims to develop a biomass estimation model based on RGB sensor-derived UAV imagery and a modified allometric equation. A total of 35 cocoa agroforestry plots were selected in Luwu Timur, South Sulawesi, based on strict biophysical and accessibility criteria. RGB imagery collected via DJI Phantom 4 UAVs was used to generate Canopy Height Models (CHMs), which were validated against field measurements of tree height and diameter. A modified allometric equation incorporating both variables were used to estimate above-ground biomass (AGB), which was subsequently converted into carbon stock values. The UAV-estimated tree heights demonstrated strong correlation with field observations (R2 = 0.7344), confirming model reliability. This technique has proven capable of substituting for tree height estimation using LiDAR, which requires more advanced and costly equipment. Estimated carbon stocks ranged from 18.41 to 134.49 tCO2e/ha, highlighting the variability across agroforestry systems shaped by diverse management practices. This study presents a replicable and scalable framework for integrating UAV-based methods into carbon finance schemes.

2

Anode materials for Li-ion batteries with Li4Ti5O12 with nickel, copper and carbon

Olszewska Danuta, Borowski Gabriel

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 3

121--133

EN

Graphite, as a form of carbon, is used in many types of Li-ion batteries. The electrochemical properties of graphite are very good for these applications. However, increasing the volume of the cell during the discharge/charge process of the battery is not a desirable feature. This can lead to overheating or even explosion of the cell. Therefore, the materials that can replace graphite are sought. Such a material can be a composite consisting of Li4Ti5O12 with a carbon material doped with copper and nickel ions. In this case, the addition of sucrose was used for better dispersion of these ions. In this way, the conductivity of the material can be improved. Anodes without carbon addition based on Li4Ti5O12 (LTO) do not change their volume during discharge/charge cycles, but have low conductivity. A significant aspect of the use of sucrose in this composite is the lack of soot addition to the cell anode. Hence, the discussed composites significantly contribute to environmental protection and safety of selected Li-ion cells. In this work, three new anode materials with stoichiometric composition Li3.8CuxNi0.2-xTi5O12 calcined with 10% sucrose were synthesized. A positive effect of sucrose addition on the cell anode operating parameters was demonstrated. Among the materials tested the preferred composition of material composition is Li3.8Cu0.05Ni0.15Ti5O12 – C.

3

Ocena możliwości wykorzystania węgla z pirolizy metanu jako biokomponentu smarów plastycznych

Skibińska Agnieszka, Sacha Dariusz, Krasodomski Wojciech, Wojtasik Michał

Rynek Energii

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2024

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Nr 3

73--77

PL

Przeprowadzono w laboratorium proces pirolizy metanu z wytworzeniem wodoru oraz węgla. Uzyskany materiał węglowy wykorzystano jako dodatek funkcyjny w smarach plastycznych, poprawiający właściwości smarne i przeciwzużyciowe. Zastosowano smary litowe, jako najpowszechniej stosowane. Porównano właściwości uzyskane w badaniu aparatem czterokulowym do właściwości analogicznych próbek smarów zawierających grafit naturalny.

EN

Evaluating the lubricating and anti-wear properties of lithium-based lubricating greases, determined in accordance with the method of PN—EN 20623, it can be concluded that the addition of both carbon and graphite allows similar results. Carbon obtained by methane pyrolysis, after appropriate grinding, can be successfully used instead of crystalline natural graphite as an additive for lubricating grease.

4

Construction of China’s Carbon Financial Accounting System from the Perspective of Sustainable Development

Li Shuwen

Problemy Ekorozwoju

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2024

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Vol. 19, no. 1

213--220

EN

Carbon Financial Accounting System highlights the importance of carbon finance and carbon accounting in China's efforts towards sustainable development and reducing its carbon footprint. The article discusses the need to manage and trade carbon assets, develop a comprehensive carbon financing system, and account for and report carbon activities. It proposes constructing a carbon accounting framework that includes all key sources of carbon emissions and carbon sequestration capacity. The article emphasizes the need to integrate carbon accounting into a company's operations and establish a comprehensive carbon finance ecosystem as a critical component of national strategic development. To achieve this, the Chinese government must promote CDM initiatives and relevant policies, enhance support to intermediary institutions, centralize the management of CDM projects, and strengthen carbon financing regulations. The article suggests establishing carbon trading and pricing mechanisms and improving the carbon trading system to create an effective carbon finance regulatory structure. Additionally, a carbon accounting system is required for financial and accounting oversight to support green and low-carbon growth, hence strengthening carbon accounting and reporting regulations of companies. The incorporation of carbon exchange, carbon funds, and carbon sinks banks are also essential in enhancing the financial accounting system.

PL

System rachunkowości węglowej podkreśla znaczenie finansowania emisji dwutlenku węgla i rozliczania emisji CO2 w wysiłkach Chin na rzecz zrównoważonego rozwoju i zmniejszenia śladu węglowego. W artykule omówiono potrzebę zarządzania aktywami węglowymi i handlu nimi, opracowania kompleksowego systemu finansowania emisji dwutlenku węgla oraz rozliczania i raportowania działalności związanej z emisjami tego gazu. Proponuje skonstruowanie ram rozliczania emisji dwutlenku węgla, które obejmują wszystkie kluczowe źródła emisji i zdolność do sekwestracji CO2. W artykule podkreślono potrzebę włączenia rachunkowości emisji dwutlenku węgla do działalności przedsiębiorstwa i ustanowienia kompleksowego ekosystemu finansowania emisji CO2 jako kluczowego elementu krajowych strategii. Aby to osiągnąć, chiński rząd musi promować inicjatywy CDM i odpowiednią politykę, zwiększyć wsparcie dla instytucji pośredniczących, scentralizować zarządzanie projektami CDM oraz wzmocnić regulacje dotyczące finansowania emisji. W artykule sugeruje się ustanowienie mechanizmów handlu uprawnieniami do emisji i ustalania cen oraz poprawę handlu uprawnieniami do emisji w celu stworzenia skutecznej struktury regulacyjnej dotyczącej finansowania emisji dwutlenku węgla. Ponadto system rozliczania emisji CO2 jest wymagany do nadzoru finansowego w celu wspierania ekologicznego i niskoemisyjnego wzrostu, a tym samym wzmocnienia przepisów dotyczących rozliczania emisji dwutlenku węgla i raportowania przedsiębiorstw. Włączenie giełd emisji CO2, funduszy węglowych i banków pochłaniających emisję dwutlenku węgla jest również niezbędne dla ulepszenia systemu rachunkowości finansowej.

5

Coal research trends - a bibliometric approach

Misiak Jacek, Uliasz-Misiak Barbara

Gospodarka Surowcami Mineralnymi

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2024

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T. 40, z. 4

5--20

EN

Coal is a cheap and accessible source of energy. However, the environmental costs associated with its exploitation and combustion are increasing. Burning coal generates large amounts of carbon dioxide. A gas that is a major contributor to global climate change. Coal is a raw material used in various technologies (from energy to medicine) and is also the subject of scientific research. The directions for its use change over time. By tracing research trends related to coal, new research directions can be identified. Bibliometric analysis is used for this purpose, using a variety of data pertaining to scientific publications observed with the development of science. This method makes it possible to analyse networks of research, national and international, and to identify the internal logic of scientific development. This article aims to analyse research topics related to the word “coal” in the period covering 1950-2023. The article presents an analysis of publications indexed in the SCOPUS database. Publications that contained phrases related to search phrases containing the word “COAL” in the title, abstract, or keywords were included in the analysis. The dynamics of changes in the interest of coal researchers in subject areas, research areas, and countries were presented. On this basis, an attempt was made to identify future leading research topics related to coal and to identify limitations and barriers to the development of this research topic.

PL

Węgiel jest tanim i dostępnym źródłem energii. Jednak środowiskowe koszty związane z jego eksploatacją i spalaniem są coraz wyższe. Spalanie węgla generuje duże ilości dwutlenku węgla. Gazu, który jest głównym czynnikiem przyczyniającym się do globalnych zmian klimatu. Węgiel jest surowcem wykorzystywanym w różnych technologiach (od energetyki po medycynę), a także przedmiotem badań naukowych. Kierunki jego wykorzystania zmieniają się wraz z czasem. Prześledzenie trendów badawczych związanych z węglem może pozwolić na wskazanie nowych kierunków badań. Do tego celu stosuje się analizę bibliometryczną wykorzystującą różnorakie dane odnoszące się do publikacji naukowych umożliwiającą obserwowanie trendów badawczych wraz z rozwojem nauki. Metoda ta pozwala na analizowanie sieci powiązań badawczych, krajowych i międzynarodowych oraz na identyfikację wewnętrznej logiki rozwoju nauki. Celem artykułu jest analiza tematów badawczych związanych ze słowem “coal” w okresie obejmującym lata 1950-2023. W artykule przedstawiono analizę publikacji indeksowanych w bazie SCOPUS. Do analizy włączono publikacje, które w tytule, streszczeniu lub słowach kluczowych zawierały wyrażenia powiązane z wyszukiwanymi frazami zawierającymi słowo “coal”. Przedstawiono dynamikę zmian zainteresowań badaczy zajmujących się węglem problematyką w: zakresach tematycznych, obszarach badawczych i krajach. Na tej podstawie podjęto próbę wyodrębnienia przyszłościowych, wiodących tematów badawczych związanych z węglem oraz wskazanie ograniczeń i barier w rozwoju tej tematyki badawczej.

6

Investigation of Post-Fire Peatland Natural Recovery, South Kalimantan, Indonesia

Wahyono Sri Cahyo, Kurnain Ahmad, Nata Iryanti Fatyasari, Asyari Mufidah

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 4

104--115

EN

Peatlands play a critical role in global habitats since are composed of heterogeneous materials and chemical reactions. Peatland fires significantly change the chemical characteristics of its soil, such as carbon (C), nitrogen (N), phosphorus (P) and potassium (K) content. This study aimed to measure peatland recovery only on those soil chemical characteristics based on two different times of sampling that are five years (Yr+5) and seven years (Yr+7) after the fires in 2015 (taken in 2020 and 2022). This study was conducted in the Balangan River - Batangalai River peat hydrological unit, South Kalimantan, Indonesia. Soil samples were collected at nine different locations, including are six locations in the areas that experienced fires in 2015 and three locations in the areas that did not experience fires. Those soil samples were taken with excavated pits at each sample location at each depth of 10, 20, 30, 40 and 50 cm. This study found that the carbon content in the post-fire area increased by 22.00% and in the natural area by 9.90%. The nitrogen content in the post-fire area increased by 1.94% and in the natural area by 1.17%. The potassium content in the post-fire areas increased by 16.33% and in the natural areas by 4.44%. The phosphorus content in the post-fire area increased by 3.18% and in the natural area by 5.11%. C/N ratio increased by 19.68% and C/P ratio increased by 18.24%. Overall, the increase in carbon, nitrogen, potassium, phosphorus, C/N ratio and C/P ratio in post-fire and natural peatlands indicates an improved condition. This study can provide supporting information for the regulator, management or expertise of the land and forest rehabilitation to speed up the recovery process.

7

Carbon dioxide capture in large-scale CCGT power plant from flue gases obtained from various fuel mixtures

Subramanian Navaneethan, Madejski Paweł

Archives of Thermodynamics

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2024

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Vol. 45, no. 4

85--93

EN

In this study, the thermodynamic analysis of a combined cycle gas turbine integrated with post-combustion carbon capture and storage using the solvent method is performed. The syngas obtained from the gasification of sewage sludge is mixed with methane and nitrogen-rich natural gas fuels at different proportions, used in the gas turbine, and the properties of fuel and flue gases are analyzed. The flue gas obtained from the fuel mixture is passed through the post-combustion carbon capture and storage at various load conditions to assess the heat and electricity required for the carbon capture process. The solvent used for the carbon capture from flue gases enables CO2 capture with the high efficiency of 90%. With the calculated results, the load conditions of flue gas using fuel mixtures are identified, which reduces the heat and power demand of post-combustion carbon capture and storage and provides the possibility to achieve neutral emission. The impact of selected operating conditions of post-combustion carbon capture and storage on the CO2 emission reduction process and on the power plant performances is investigated. Considering the factors of electricity generation, energy efficiency, heat supply to the consumers, operating load of post-combustion carbon capture and storage and CO2 emission, the 50% mixture of syngas with both fuels performs better. Also, the use of a mixture of 2-amino-2methyl-1-propanol and piperazine with reboiler duty 3.7 MJ/kgCO2 in post-combustion carbon capture and storage slightly enhanced the performance of the power plant compared to the use of monoethanolamine with reboiler duty 3.8 MJ/kgCO2.

8

Stacking Effect of Carbon/Glass Fiber During Drilling Operation of Laminated Polymer Composite

Dubey Ankit Dhar, Kumar Jogendra, Kyratsis Panagiotis, Verma Rajesh

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 2

589--598

EN

Nowadays, fiber stacks are extensively used in the aircraft and structural component manufacturing industries. It is mainly due to their excellent mechanical and physiochemical performances. The different stacking sequences of fiber materials expand the structural properties due to high-strength carbon fiber and low-cost glass fiber. The fragile and anisotropic conduct of Carbon (Cf) and Glass (Gf) laminates generates different types of complex machining issues. This article focuses on the Drilling test of Carbon/glass fiber hybrid composites using different stacking sequences. The effect of varying stacking orders is explored in this study to identify a feasible composite. The control of varying constraints, namely, spindle speed (N), feed rate (f), and stacking sequence (SS) of carbon (Cf) and glass fiber (Gf) reinforcement, is performed to achieve the optimal parametric condition. The finding reveals that sample A (C4G4) stacking sequence provides an acceptable value for thrust force 59.05 N and delamination 1.0001 for high drilling efficiency. The stacking technique of carbon/glass layers can be endorsed to the manufacturing sector for cost-effective composite development and a defect-free machining environment.

9

Power and Energy Optimization of Carbon Based Lithium-Ion Battery from Water Spinach (Ipomoea Aquatica)

Santoso Budi, Ammarullah Muhammad Imam, Haryati Sri, Sofijan Armin, Bustan Muhammad Djoni

Journal of Ecological Engineering

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2023

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Vol. 24, nr 3

213--223

EN

Currently, lithium-ion batteries still use electrodes from graphite, which is a natural resource for non-metallic minerals. As a sustainable plan, research on the manufacture of lithium-ion batteries based on biomass electrodes has prospects for commercial development. In this study, carbon stems of water spinach (Ipomoea Aquatica) were used as electrodes on the battery. Water spinach is processed into nanocarbon by hydrothermal method and pyrolysis. The size of the nanocarbon particles from water spinach in this study was 200 mesh resulting from the grinding method. The type of battery made is a bag battery with a size of 8×12 cm by performing variable optimization by using a concentration of 50% LiCl/Li2SO4 electrolytes media, Polyurethane/Polyacrylate binder, and Triethylamine/Non-emulsifier. The highest power and energy values are generated from carbon based lithium-ion batteries from water spinach with LiCl electrolyte media, Polyurethane binder, and Triethylamine emulsion which is 5.404 W and 4.511 W∙h.

10

Analysis of the Use of Biochar from Organic Waste Pyrolysis in Agriculture and Environmental Protection

Niedziński Tomasz, Łabętowicz Jan, Stępień Wojciech, Pęczek Tadeusz

Journal of Ecological Engineering

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2023

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Vol. 24, nr 4

85--98

EN

Nowadays, research on the use of pyrolysis products in the broadly understood economy is widely conducted in the world. This publication presents the results of research on the use of biochar primarily as a material for use in agriculture and environmental protection. In particular, its use to improve soil properties and as a component of organic fertilisers or composts, as well as an ingredient for animal bedding in livestock buildings or an additive for silage is discussed. In addition, the possibilities of using biochar in the energy sector as a solid fuel and in the broader field of environmental protection for remediation of contaminated land, for carbon sequestration and as a raw material for the production of activated carbons are discussed.

11

Zastosowanie materiałów mezoporowatych jako adsorbentów w metodzie ekstrakcji ciecz-ciało stałe

Geszke-Moritz Małgorzata, Pyć Agnieszka, Stoińska Aleksandra, Lis Weronika, Moritz Michał

Przemysł Chemiczny

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2022

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T. 101, nr 8

602--605

PL

Przedstawiono zastosowania materiałów mezoporowatych jako adsorbentów w procesie zatężania analitu metodą ekstrakcji w układzie ciecz-ciało stałe. Najczęściej stosowanymi adsorbentami są mezoporowate krzemionki oraz węgle. Modyfikacja powierzchni adsorbentów może przyczynić się do zwiększenia ich selektywności wobec adsorbowanych substancji. Metoda ekstrakcji w układzie ciecz-ciało stałe jest najczęściej stosowana podczas oznaczania substancji metodami chromatograficznymi (HPLC, UPLC, GC).

EN

A review, with 29 refs., of historical and new methods of obtaining mesoporous materials, including their properties and applications. The use of these materials in the detn. of trace amts. of an analyte was discussed. Particular attention was paid to the types and methods of preparing the porous phase for anal. purposes, its properties and the method of sepn. from the analyte (molecular imprinting, magnetic nanoparticles).

12

Bonding methods of ceramic materials with deposited carbon layers

Matusiak Tomasz, Kaszczyszyn Jakub, Dąbrowski Arkadiusz

Przegląd Elektrotechniczny

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2022

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R. 98, nr 1

55--58

EN

In this paper, we present a proposed bonding technology of ceramic materials. It could be applied for manufacturing the excitation source for detection of elements by means of Optical Emission Spectroscopy (OES) method. The biggest challenge was choice of proper bonding technology for materials with screen printed carbon layers as an excitation electrodes. It was caused by a need to avoid a deterioration of electrical properties of the carbon layer during the bonding process. The bonding at low temperature with various glaze layers was verified with addition of noble elements and plasma modification. The results were promising, without any significant destruction of carbon layers.

PL

W tym artykule przedstawiamy proponowaną technologię łączenia materiałów ceramicznych która może być zastosowana przy wytwarzaniu źródła wzbudzenia do detekcji pierwiastków w metodzie optycznej spektroskopii emisyjnej. Wybór odpowiedniej technologii łączenia materiału z warstwami węglowymi wytwarzanymi metodą sitodruku był wyzwaniem z powodu konieczności uniknięcia degradacji właściwości elektrycznych węgla podczas procesu łączenia. Zweryfikowano łączenie w niskiej temperaturze z różnymi warstwami szkliwa z dodatkiem pierwiastków szlachetnych i modyfikacją plazmową. Wyniki były obiecujące, bez znacznego zniszczenia warstw węglowych.

13

Allometry, biomass and productivity in pinus massoniana forests of China: an updated review of published data

Jin Ling, Li Xiaodong, Huang Qiuchan, Yang Honglan, Huang Ju

Polish Journal of Ecology

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2022

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Vol. 70, nr 1

1--32

EN

Field measurements of forest biomass are labor-consuming and usually destructive, but such direct datasets are the foundation for further developing indirect estimation such as biomass equation and biomass expansion factors that were used to scale biomass estimation or carbon storage from site or local surveys up to regional or national level. Pinus massoniana is widely distributed throughout 17 provinces of China and has a high economic value. This study is an updated review of the allometric equations, biomass allocation data and productivity estimations in Pinus massoniana forests of China published in articles during the period from 1982 to 2019. Different allometric equations of Pinus massoniana showed site-specific dependences. The aboveground and total tree biomass were expressed as power equations of mean age for Pinus massoniana forests. The mean value of aboveground tree biomass, total tree biomass and ecosystem biomass across all ages for Masson pine forests was 109.81, 127.65 and 138.76 Mg/ha, respectively. The mean proportion of stem, branch and foliage to aboveground tree biomass for Pinus massoniana was 77.1%, 15.9% and 7%, respectively. The tree root biomass continuously increased with the aboveground tree biomass and a power relationship was found between the tree root biomass and aboveground tree biomass for Pinus massoniana forests. The tree net primary productivity increased with aboveground tree biomass for Pinus massoniana forests, and the relationship was expressed as a linear equation. The mean tree, litter and ecosystem net primary productivity was 7.04, 4.88 and 8.30 Mg/ha/year, respectively. These findings provide key parameters for the biomass estimation and carbon accounting studies of widely planted Pinus massoniana forests in China.

14

Co warto wiedzieć o węglu

Dziok Tadeusz

Energia i Recykling : gospodarka obiegu zamkniętego

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2022

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nr 12

PL

Węgiel od lat jest wykorzystywany w polskich domach, lecz wiedza na jego temat nadal jest niewystarczająca. Eksperci Akademii Górniczo-Hutniczej w Krakowie przygotowali zestawienie najważniejszych informacji dotyczących tego surowca, szczególnie przydatnych przy wykorzystaniu go jako głównego źródła ciepła.

15

Adsorption Kinetic and Isotherm Studies of Reactive Red B Textile Dye Removal Using Activated Coconut Leaf Stalk

Sudiana I. Ketut, Sastrawidana I. Dewa Ketut, Sukarta I. Nyoman

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 5

61--71

EN

Textile wastewater has become one of the serious environmental problems due to containing a high concentration of chemicals with extreme color intensity. Reactive red RB is among the synthetic azo dyes commonly used as a textile colorant with their property are very difficult to degrade naturally. This research was focused on studying the kinetic behavior, and adsorption isotherm of reactive red RB textile dye on coconut leaf stalk activated carbon (CLSC). Coconut leaf stalk carbon was activated using sulphuric acid and sodium hydroxide. It was investigated in terms of chemical functional groups, surface morphology, carbon content, ash content, and adsorption efficiency of reactive red RB textile dye under various conditions of initial pH, incubation time, and dye concentration. The results showed the maximum adsorption efficiency of reactive red RB dye with a concentration dye of 60 mg/l onto CLSC surface activated by sulfuric acid and sodium hydroxide in an experiment carried out at pH 5 for 120 min were 88.73% and 64.27%, respectively. The adsorption isotherm of reactive red RB on the CLSC surface follows the Langmuir isotherm model, which shows that the adsorption process occurs monolayer. In contrast, the adsorption kinetics correspond to pseudo-second-order.

16

Znaczenie alotropii wybranych pierwiastków chemicznych oraz polimorfizmu ich związków

Badora Aleksandra, Celińska Magdalena, Filipek Tadeusz

Przemysł Chemiczny

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2021

|

T. 100, nr 2

168--172

PL

Wiele pierwiastków chemicznych oraz ich związków ma szerokie zastosowanie w produktach dostępnych na rynku. Są obecne zarówno w produktach żywnościowych, preparatach leczniczych, jak i w kosmetykach. Na podstawie przeglądu literatury i danych producenta dokonano analizy ich aktywności oraz potencjalnych korzyści i zagrożeń wynikających z ich stosowania. Przeanalizowano też wpływ tych substancji na środowisko naturalne.

EN

A review, with 35 refs., of chem. elements and their comps. used in foods, drugs and cosmetics. Their activity, potential benefits and risks as well as environmental impacts were taken into consideration.

17

Wstępna charakterystyka mineralogiczna czarnych łupków antrakozjowych z obszaru synklinorium śródsudeckiego

Wójcik-Tabol Patrycja, Dąbek Jolanta, Nowak Grzegorz J.

Przegląd Geologiczny

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2021

|

Vol. 69, nr 6

389--392

EN

Anthracosia Shales within the Pennsylvanian-Lower Permian continental succession from the Intra-Sudetic Synclinorium are lacustrine sediments, represented by black shales intercalated with sandstones/mudstones. Mineral composition of each lithology consists of quartz, feldspar, mica, clay minerals (including kaolinite, the content of which decreases upward the section), and carbonates (calcite and siderite). The section is a continuous record of reduction and rise in terrigenous input. Mineral detritus is least weathered in the uppermost part of the Anthracosia Shales. The sedimentation occurred under dysoxic conditions that were ventilated by bottom currents.

18

Influence of heat treatment of carbon nanofibers on genotoxicity

Frączek-Szczypta Aneta, Panek Agnieszka, Marczyk Monika, Zambrzycki Marcel

Engineering of Biomaterials

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2021

|

Vol. 24, no. 163

115

19

Carbon nanomaterials based chemiresistive gas sensors

Wróbel Paweł S., Kordyka Aleksandra, Bachmatiuk Alicja, Pusz Sławomir, Hercog Anna, Szabo Ondrej, Potocký Ŝtěpán

Engineering of Biomaterials

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2021

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Vol. 24, no. 163

75

20

Numerical investigation of convective heat transfer of single wall carbon nanotube nanofluid laminar flow inside a circular tube

Saeed Farqad Rasheed, Jasim Marwah A., Mahmood Natheer B., Jaffar Zahraa M.

Archives of Thermodynamics

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2021

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Vol. 42, no. 2

103--119

EN

This study presents the behavior of a single wall carbon nanotube (SWCNT)/water nanofluid for convective laminar flow inside a straight circular pipe heated by a constant heat flux. Five volume fractions of SWCNT were used to investigate their effect on the heat transfer coefficient, Nusselt number, temperature distribution and velocity field in comparison with pure water flow. One model for each property was tested to calculate the effective thermal conductivity, effective dynamic viscosity, and effective specific heat of the SWCNT/water mixture. The models were extracted from experimental data of a previous work. The outcomes indicate that the rheological behavior of SWCNT introduces a special effect on the SWCNT/water properties, which vary with SWCNT volume fraction. The results show an improvement in the heat transfer coefficient with increasing volume fraction of nanoparticles. The velocity of SWCNT/water nanofluid increased by adding SWCNT nanoparticles, and the maximum increase was registered at 0.05% SWCNT volume fraction. The mixture temperature is increased with the axial distance of the pipe but a reduction in temperature distribution is observed with the increasing SWCNT volume fraction, which reflects the effect of thermophysical properties of the mixture.