4,008 research outputs found
Highly porous alkali activated foams for water and wastewater treatment
No full textAbstract
Alkali-activated materials (AAMs) have diverse applications in water and wastewater treatment. In this thesis, porous AAM foams were prepared with the goal to explore their potential use in new applications for water and wastewater treatment, namely adsorptive filters, point-of-use water disinfection, and separation of microplastics.
The adsorptive filters were prepared from blast furnace slag and optimized by comparing five different surfactants and doses of H2O2. Porous AAM exhibiting the highest mechanical strength was investigated for methylene blue adsorption. To further enhance the adsorption performance, a lignin-containing composite foam was prepared. In the dynamic adsorption experiments, the highest adsorption amount obtained with the lignin-composite foam was ~40 mg/g. Moreover, peracetic acid was investigated as an alternative foaming agent in the preparation of porous AAMs. During the investigation, lower volume expansion and faster reaction kinetics with reduced setting time were observed for peracetic acid-based porous AAM compared to H2O2-based porous AAM.
To develop material for point-of-use water disinfection, the first goal was to achieve comparable water permeability to traditional ceramic filters by varying the amount of hydrogen peroxide. An optimized foam was then treated with colloidal Ag solution to explore its potential use in disinfecting water for 10 weeks. The modified foam demonstrated a significant reduction (2.84 log10 units) in E. coli bacteria compared to an unmodified filter (1.57 log10 units). Additionally, the environmental impact of the porous AAM was analyzed through life cycle assessment and found to be lower than that of conventional ceramic filter.
Finally, to develop material capable of separating microplastics, porous AAM surface was modified with triethoxy(octyl)silane to render it superhydrophobic. The modified porous AAM demonstrated over 99% separation efficiency when treating 30 L of model water containing 5 mg/L of polyethylene microspheres (53-63 μm). Its performance was also evaluated in treating laundry effluent, where the modified porous AAM achieved approximately 84% separation compared to around 52% for the unmodified porous AAM. Original papers Bhuyan, M. A. H., Gebre, R. K., Finnilä, M. A. J., Illikainen, M., & Luukkonen, T. (2022). Preparation of filter by alkali activation of blast furnace slag and its application for dye removal. Journal of Environmental Chemical Engineering, 10(1), 107051. https://doi.org/10.1016/j.jece.2021.107051 https://doi.org/10.1016/j.jece.2021.107051 Self-archived version Bhuyan, M. A. H., & Luukkonen, T. (2024). Adsorption of methylene blue by composite foams containing alkali-activated blast furnace slag and lignin. International Journal of Environmental Science and Technology, 21(4), 3789–3802. https://doi.org/10.1007/s13762-023-05245-5 https://doi.org/10.1007/s13762-023-05245-5 Self-archived version Bhuyan, M. A. H., Kurtulus, C., Heponiemi, A., & Luukkonen, T. (2023). Peracetic acid as a novel blowing agent in the direct foaming of alkali-activated materials. Applied Clay Science, 231, 106727. https://doi.org/10.1016/j.clay.2022.106727 https://doi.org/10.1016/j.clay.2022.106727 Self-archived version Bhuyan, M. A. H., Karkman, A., Prokkola, H., Chen, B., Perumal, P., & Luukkonen, T. (2024). Alkali-activated foams coated with colloidal Ag for point-of-use water disinfection. ACS ES&T Water, 4(2), 687–697. https://doi.org/10.1021/acsestwater.3c00711 https://doi.org/10.1021/acsestwater.3c00711 Self-archived version Bhuyan, M. A. H., Busquets, R., Campos, L. C., & Luukkonen, T. (2024). Separation of microplastics from water using superhydrophobic silane-coupling-agent-modified geopolymer foam. Separation and Purification Technology, 339, 126709. https://doi.org/10.1016/j.seppur.2024.126709 https://doi.org/10.1016/j.seppur.2024.126709 Self-archived version Abstrakti
Alkaliaktivoiduilla materiaaleilla on runsaasti erilaisia sovelluksia veden ja jäteveden käsittelyssä. Tässä väitöskirjassa valmistettiin huokoisia alkaliaktivoituja vaahtoja tavoitteena selvittää niiden uusia hyödyntämismahdollisuuksia adsorboivina suodatinmateriaaleina, veden desinfioinnissa ja mikromuovin erottamisessa.
Masuunikuonasta valmistettujen adsorboivien suodattimien koostumus optimoitiin muuttamalla valmistuksessa käytetyn pinta-aktiivisen aineen tyyppiä sekä vaahdotinaineena toimivan vetyperoksidin lisäysmäärää. Optimoidulla materiaalilla tutkittiin metyleenisinisen adsorptiota vedestä. Adsorptiokyvyn lisäämiseksi valmistettiin ligniiniä sisältävää komposiittimateriaalia. Dynaamisessa metyleenisinisen adsorptiokokeessa suurin adsorptiomäärä ligniinikomposiitille oli ~40 mg/g. Lisäksi peretikkahappoa tutkittiin vaihtoehtoisena vaahdotusaineena. Peretikkahappoa käytettäessä havaittiin pienempi turpoaminen valmistuksen aikana ja lyhyempi kovettumisaika verrattuna vetyperoksidilla valmistettuihin vaahtoihin.
Tutkimuksen seuraavassa osassa tutkittiin veden desinfiointia. Alkaliaktivoituja vaahtoja valmistettiin metakaoliinista, masuunikuonasta ja niiden seoksista tavoitteena saavuttaa samanlainen veden läpäisevyys kuin keraamisilla suodattimilla. Tämän jälkeen optimoitua vaahtoa käsiteltiin kolloidisella hopealiuoksella ja sen käyttömahdollisuuksia veden desinfioinnissa tutkittiin 10 viikon ajan. Hopeaa sisältävä vaahto osoitti merkittävää E. coli -bakteerien vähenemistä (2,84 log10) verrattuna hopeaa sisältämättömään suodattimeen (1,57 log10). Lisäksi alkaliaktivoidun vaahdon ympäristövaikutuksia analysoitiin elinkaariarvioinnin avulla ja niiden todettiin olevan pienempiä kuin perinteisen keraamin.
Mikromuovien erottamiseksi alkaliaktivoituja vaahtoja käsiteltiin trietoksi(oktyyli)silaanilla superhydrofobisen pinnan luomiseksi. Käsitelty vaahto poisti yli 99 % mikromuovista kokeessa, jossa käsiteltiin 30 litraa vettä, joka sisälsi 5 mg/l polyetyleenipartikkeleita (koko 53–63 μm). Käsitellyn vaahdon suorituskykyä arvioitiin myös pyykinpesuveden käsittelyssä, jossa sen muovin poistokyky oli noin 84 % kun taas ei-käsitelty vaahto poisti vain 52 %. Osajulkaisut Bhuyan, M. A. H., Gebre, R. K., Finnilä, M. A. J., Illikainen, M., & Luukkonen, T. (2022). Preparation of filter by alkali activation of blast furnace slag and its application for dye removal. Journal of Environmental Chemical Engineering, 10(1), 107051. https://doi.org/10.1016/j.jece.2021.107051 https://doi.org/10.1016/j.jece.2021.107051 Rinnakkaistallennettu versio Bhuyan, M. A. H., & Luukkonen, T. (2024). Adsorption of methylene blue by composite foams containing alkali-activated blast furnace slag and lignin. International Journal of Environmental Science and Technology, 21(4), 3789–3802. https://doi.org/10.1007/s13762-023-05245-5 https://doi.org/10.1007/s13762-023-05245-5 Rinnakkaistallennettu versio Bhuyan, M. A. H., Kurtulus, C., Heponiemi, A., & Luukkonen, T. (2023). Peracetic acid as a novel blowing agent in the direct foaming of alkali-activated materials. Applied Clay Science, 231, 106727. https://doi.org/10.1016/j.clay.2022.106727 https://doi.org/10.1016/j.clay.2022.106727 Rinnakkaistallennettu versio Bhuyan, M. A. H., Karkman, A., Prokkola, H., Chen, B., Perumal, P., & Luukkonen, T. (2024). Alkali-activated foams coated with colloidal Ag for point-of-use water disinfection. ACS ES&T Water, 4(2), 687–697. https://doi.org/10.1021/acsestwater.3c00711 https://doi.org/10.1021/acsestwater.3c00711 Rinnakkaistallennettu versio Bhuyan, M. A. H., Busquets, R., Campos, L. C., & Luukkonen, T. (2024). Separation of microplastics from water using superhydrophobic silane-coupling-agent-modified geopolymer foam. Separation and Purification Technology, 339, 126709. https://doi.org/10.1016/j.seppur.2024.126709 https://doi.org/10.1016/j.seppur.2024.126709 Rinnakkaistallennettu versio Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Technology and Natural Sciences of the University of Oulu for public defence in the Arina auditorium (TA105), Linnanmaa, on 3 May 2024, at 12 noonAbstract
Alkali-activated materials (AAMs) have diverse applications in water and wastewater treatment. In this thesis, porous AAM foams were prepared with the goal to explore their potential use in new applications for water and wastewater treatment, namely adsorptive filters, point-of-use water disinfection, and separation of microplastics.
The adsorptive filters were prepared from blast furnace slag and optimized by comparing five different surfactants and doses of H2O2. Porous AAM exhibiting the highest mechanical strength was investigated for methylene blue adsorption. To further enhance the adsorption performance, a lignin-containing composite foam was prepared. In the dynamic adsorption experiments, the highest adsorption amount obtained with the lignin-composite foam was ~40 mg/g. Moreover, peracetic acid was investigated as an alternative foaming agent in the preparation of porous AAMs. During the investigation, lower volume expansion and faster reaction kinetics with reduced setting time were observed for peracetic acid-based porous AAM compared to H2O2-based porous AAM.
To develop material for point-of-use water disinfection, the first goal was to achieve comparable water permeability to traditional ceramic filters by varying the amount of hydrogen peroxide. An optimized foam was then treated with colloidal Ag solution to explore its potential use in disinfecting water for 10 weeks. The modified foam demonstrated a significant reduction (2.84 log10 units) in E. coli bacteria compared to an unmodified filter (1.57 log10 units). Additionally, the environmental impact of the porous AAM was analyzed through life cycle assessment and found to be lower than that of conventional ceramic filter.
Finally, to develop material capable of separating microplastics, porous AAM surface was modified with triethoxy(octyl)silane to render it superhydrophobic. The modified porous AAM demonstrated over 99% separation efficiency when treating 30 L of model water containing 5 mg/L of polyethylene microspheres (53-63 μm). Its performance was also evaluated in treating laundry effluent, where the modified porous AAM achieved approximately 84% separation compared to around 52% for the unmodified porous AAM.Abstrakti
Alkaliaktivoiduilla materiaaleilla on runsaasti erilaisia sovelluksia veden ja jäteveden käsittelyssä. Tässä väitöskirjassa valmistettiin huokoisia alkaliaktivoituja vaahtoja tavoitteena selvittää niiden uusia hyödyntämismahdollisuuksia adsorboivina suodatinmateriaaleina, veden desinfioinnissa ja mikromuovin erottamisessa.
Masuunikuonasta valmistettujen adsorboivien suodattimien koostumus optimoitiin muuttamalla valmistuksessa käytetyn pinta-aktiivisen aineen tyyppiä sekä vaahdotinaineena toimivan vetyperoksidin lisäysmäärää. Optimoidulla materiaalilla tutkittiin metyleenisinisen adsorptiota vedestä. Adsorptiokyvyn lisäämiseksi valmistettiin ligniiniä sisältävää komposiittimateriaalia. Dynaamisessa metyleenisinisen adsorptiokokeessa suurin adsorptiomäärä ligniinikomposiitille oli ~40 mg/g. Lisäksi peretikkahappoa tutkittiin vaihtoehtoisena vaahdotusaineena. Peretikkahappoa käytettäessä havaittiin pienempi turpoaminen valmistuksen aikana ja lyhyempi kovettumisaika verrattuna vetyperoksidilla valmistettuihin vaahtoihin.
Tutkimuksen seuraavassa osassa tutkittiin veden desinfiointia. Alkaliaktivoituja vaahtoja valmistettiin metakaoliinista, masuunikuonasta ja niiden seoksista tavoitteena saavuttaa samanlainen veden läpäisevyys kuin keraamisilla suodattimilla. Tämän jälkeen optimoitua vaahtoa käsiteltiin kolloidisella hopealiuoksella ja sen käyttömahdollisuuksia veden desinfioinnissa tutkittiin 10 viikon ajan. Hopeaa sisältävä vaahto osoitti merkittävää E. coli -bakteerien vähenemistä (2,84 log10) verrattuna hopeaa sisältämättömään suodattimeen (1,57 log10). Lisäksi alkaliaktivoidun vaahdon ympäristövaikutuksia analysoitiin elinkaariarvioinnin avulla ja niiden todettiin olevan pienempiä kuin perinteisen keraamin.
Mikromuovien erottamiseksi alkaliaktivoituja vaahtoja käsiteltiin trietoksi(oktyyli)silaanilla superhydrofobisen pinnan luomiseksi. Käsitelty vaahto poisti yli 99 % mikromuovista kokeessa, jossa käsiteltiin 30 litraa vettä, joka sisälsi 5 mg/l polyetyleenipartikkeleita (koko 53–63 μm). Käsitellyn vaahdon suorituskykyä arvioitiin myös pyykinpesuveden käsittelyssä, jossa sen muovin poistokyky oli noin 84 % kun taas ei-käsitelty vaahto poisti vain 52 %
Mathematics, Logic, and their Philosophies:Essays in Honour of Mohammad Ardeshir
No full textThis volume is a collection of essays in honour of Professor Mohammad Ardeshir. It examines topics which, in one way or another, are connected to the various aspects of his multidisciplinary research interests. Based on this criterion, the book is divided into three general categories. The first category includes papers on non-classical logics, including intuitionistic logic, constructive logic, basic logic, and substructural logic. The second category is made up of papers discussing issues in the contemporary philosophy of mathematics and logic. The third category contains papers on Avicenna’s logic and philosophy.Mohammad Ardeshir is a full professor of mathematical logic at the Department of Mathematical Sciences, Sharif University of Technology, Tehran, Iran, where he has taught generations of students for around a quarter century. Mohammad Ardeshir is known in the first place for his prominent works in basic logic and constructive mathematics. His areas of interest are however much broader and include topics in intuitionistic philosophy of mathematics and Arabic philosophy of logic and mathematics. In addition to numerous research articles in leading international journals, Ardeshir is the author of a highly praised Persian textbook in mathematical logic. Partly through his writings and translations, the school of mathematical intuitionism was introduced to the Iranian academic community
Mathematics, Logic, and their Philosophies:Essays in Honour of Mohammad Ardeshir
No full textThis volume is a collection of essays in honour of Professor Mohammad Ardeshir. It examines topics which, in one way or another, are connected to the various aspects of his multidisciplinary research interests. Based on this criterion, the book is divided into three general categories. The first category includes papers on non-classical logics, including intuitionistic logic, constructive logic, basic logic, and substructural logic. The second category is made up of papers discussing issues in the contemporary philosophy of mathematics and logic. The third category contains papers on Avicenna’s logic and philosophy.Mohammad Ardeshir is a full professor of mathematical logic at the Department of Mathematical Sciences, Sharif University of Technology, Tehran, Iran, where he has taught generations of students for around a quarter century. Mohammad Ardeshir is known in the first place for his prominent works in basic logic and constructive mathematics. His areas of interest are however much broader and include topics in intuitionistic philosophy of mathematics and Arabic philosophy of logic and mathematics. In addition to numerous research articles in leading international journals, Ardeshir is the author of a highly praised Persian textbook in mathematical logic. Partly through his writings and translations, the school of mathematical intuitionism was introduced to the Iranian academic community
Classifying Food Items During an Eating Occasion: A Machine Learning Approach with Slope Dynamics for Windowed Kinetic Data
No full textBackground: Wearable devices equipped with a range of sensors have emerged as promising tools for monitoring and improving individuals’ health and lifestyle. Objectives: Contribute to the investigation and development of effective and reliable methods for dietary monitoring based on raw kinetic data generated by wearable devices. Methods: This study uses resources from the NOTION study. A total of 20 healthy subjects (9 women and 11 men, aged 20–31 years) were equipped with two commercial smartwatches during four eating occasions under semi-naturalistic conditions. All meals were video-recorded, and acceleration data were extracted and analyzed. Food recognition on these features was performed using random forest (RF) models with 5-fold cross-validation. The performance of the classifiers was expressed in out-of-bag sensitivity and specificity. Results: Acceleration along the x-axis and power show the highest and lowest rates of median variable importance, respectively. Increasing the window size from 1 to 5 s leads to a gain in performance for almost all food items. The RF classifier reaches the highest performance in identifying meatballs (89.4% sensitivity and 81.6% specificity) and the lowest in identifying sandwiches (74.6% sensitivity and 72.5% specificity). Conclusions: Monitoring food items using simple wristband-mounted wearable devices is feasible and accurate for some foods while unsatisfactory for others. Machine learning tools are necessary to deal with the complexity of signals gathered by the devices, and research is ongoing to improve accuracy further and work on large-scale and real-time implementation and testing
Landlessness in rural Bangladesh a study in Comilla Kotwali Thana - by Md. Abdus Sattar Bhuyan
No full textThesis (M.S.)--Faculty of Agricultural and Food Sciences, A.U.B
Mathematics, Logic, and their Philosophies:Essays in Honour of Mohammad Ardeshir
No full textThis volume is a collection of essays in honour of Professor Mohammad Ardeshir. It examines topics which, in one way or another, are connected to the various aspects of his multidisciplinary research interests. Based on this criterion, the book is divided into three general categories. The first category includes papers on non-classical logics, including intuitionistic logic, constructive logic, basic logic, and substructural logic. The second category is made up of papers discussing issues in the contemporary philosophy of mathematics and logic. The third category contains papers on Avicenna’s logic and philosophy.Mohammad Ardeshir is a full professor of mathematical logic at the Department of Mathematical Sciences, Sharif University of Technology, Tehran, Iran, where he has taught generations of students for around a quarter century. Mohammad Ardeshir is known in the first place for his prominent works in basic logic and constructive mathematics. His areas of interest are however much broader and include topics in intuitionistic philosophy of mathematics and Arabic philosophy of logic and mathematics. In addition to numerous research articles in leading international journals, Ardeshir is the author of a highly praised Persian textbook in mathematical logic. Partly through his writings and translations, the school of mathematical intuitionism was introduced to the Iranian academic community
Mathematics, Logic, and their Philosophies:Essays in Honour of Mohammad Ardeshir
No full textThis volume is a collection of essays in honour of Professor Mohammad Ardeshir. It examines topics which, in one way or another, are connected to the various aspects of his multidisciplinary research interests. Based on this criterion, the book is divided into three general categories. The first category includes papers on non-classical logics, including intuitionistic logic, constructive logic, basic logic, and substructural logic. The second category is made up of papers discussing issues in the contemporary philosophy of mathematics and logic. The third category contains papers on Avicenna’s logic and philosophy.Mohammad Ardeshir is a full professor of mathematical logic at the Department of Mathematical Sciences, Sharif University of Technology, Tehran, Iran, where he has taught generations of students for around a quarter century. Mohammad Ardeshir is known in the first place for his prominent works in basic logic and constructive mathematics. His areas of interest are however much broader and include topics in intuitionistic philosophy of mathematics and Arabic philosophy of logic and mathematics. In addition to numerous research articles in leading international journals, Ardeshir is the author of a highly praised Persian textbook in mathematical logic. Partly through his writings and translations, the school of mathematical intuitionism was introduced to the Iranian academic community
Mathematics, Logic, and their Philosophies:Essays in Honour of Mohammad Ardeshir
No full textThis volume is a collection of essays in honour of Professor Mohammad Ardeshir. It examines topics which, in one way or another, are connected to the various aspects of his multidisciplinary research interests. Based on this criterion, the book is divided into three general categories. The first category includes papers on non-classical logics, including intuitionistic logic, constructive logic, basic logic, and substructural logic. The second category is made up of papers discussing issues in the contemporary philosophy of mathematics and logic. The third category contains papers on Avicenna’s logic and philosophy.Mohammad Ardeshir is a full professor of mathematical logic at the Department of Mathematical Sciences, Sharif University of Technology, Tehran, Iran, where he has taught generations of students for around a quarter century. Mohammad Ardeshir is known in the first place for his prominent works in basic logic and constructive mathematics. His areas of interest are however much broader and include topics in intuitionistic philosophy of mathematics and Arabic philosophy of logic and mathematics. In addition to numerous research articles in leading international journals, Ardeshir is the author of a highly praised Persian textbook in mathematical logic. Partly through his writings and translations, the school of mathematical intuitionism was introduced to the Iranian academic community
'Fatherless' of Mohammad Mosavat: The cultural event of the Iranian spring
No full textThe following is a psychoanalytic commentary about a play recently performed in Tehran (Iran) followed by an interview with its author, Mohammad Mosavat. The co-signatories both attended a performance of this play. Invited by Shahid Behesti, Alzahra, and Shiraz Universities for many public lectures and supervisions, the French psychoanalyst Jean-Luc Vannier signs the commentary while the interview and the translation were conducted by the Iranian psychoanalyst in training at the Freudian Group of Tehran, Mahyar Ali Naghi
RoMEO Studies 4: An analysis of Journal publishers' Copyright Agreements
No full textThis article is the fourth in a series of six emanating from the UK JISC-funded RoMEO Project (Rights Metadata for Open archiving). It describes an analysis of 80 scholarly journal publishers’ copyright agreements with a particular view to their effect on author self-archiving. 90% of agreements asked for copyright transfer and 69% asked for it prior to refereeing the paper. 75% asked authors to warrant that their work had not been previously published although only two explicitly stated that they viewed self-archiving as prior publication. 28.5% of agreements provided authors with no usage rights over their own paper. Although 42.5% allowed self-archiving in some format, there was no consensus on the conditions under which self-archiving could take place. The article concludes that author-publisher copyright agreements should be reconsidered by a working party representing the needs of both partie
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