2,118 research outputs found
Composition of pteroylpolyglutamates (conjugated folates) into guinea pig liver and their formation from folic acid
No full text
Observation of and
No full textInternational audienceWe report the study of B+→pΛ¯K+K- and B+→p¯ΛK+K+ decays using a 772×106 BB¯ pair data sample recorded on the ϒ(4S) resonance with the Belle detector at KEKB. The following branching fractions are measured: B(B+→pΛ¯K+K-)=(4.10-0.43+0.45±0.50)×10-6, B(B+→p¯ΛK+K+)=(3.70-0.37+0.39±0.44)×10-6, B(ηc→pΛ¯K-+c.c.)=(2.83-0.34+0.36±0.35)×10-3 and B(B+→pΛ¯ϕ)=( 7.95±2.09±0.77)×10-7, where c.c. denotes the corresponding charge-conjugation process. The intermediate resonance decays are excluded in the four-body decay measurements. We also find evidence for B(ηc→Λ(1520)Λ¯+c.c.)=(3.48±1.48±0.46)×10-3 and B(B+→Λ(1520)Λ¯K+)=( 2.23±0.63±0.25)×10-6. No significant signals are found for J/ψ→Λ(1520)Λ¯+c.c. and B+→Λ¯(1520)ΛK+; we set the 90% confidence level upper limits on their decay branching fractions as <1.80×10-3 and <2.08×10-6, respectively
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 %
Measurements of the branching fractions B (B ̄0 → D∗+ π-) and B(B ̄0 →D∗+ K-) and tests of QCD factorization
No full textUsing (771.6±10.6)×106 BB ̄ meson pairs recorded by the Belle experiment at the KEKB e+e- collider, we report the branching fractions B(B ̄0→D∗+π-)=(2.62±0.02±0.09)×10-3 and B(B ̄0→D∗+K-)=(2.22±0.06±0.08)×10-4; the quoted uncertainties are statistical and systematic, respectively. A measurement of the ratio of these branching fractions is also presented, RK/π=B(B ̄→D∗+K-)/B(B ̄→D∗+π-)=(8.41±0.24±0.13)×10-2, where systematic uncertainties due to the D∗+ meson reconstruction cancel out. Furthermore, we report a new QCD factorization test based on the measured ratios for B ̄→D∗+h- and B ̄→D∗+l-ν decays at squared momentum transfer values equivalent to the mass of the h=π or K hadron. The parameters |a1(h)| are measured to be |a1(π)|=0.884±0.004±0.003±0.016 and |a1(K)|=0.913±0.019±0.008±0.013, where the last uncertainties account for all external inputs. These values are approximately 15% lower than those expected from theoretical predictions. Subsequently, flavor SU(3) symmetry is tested by measuring the ratios for pions and kaons, |a1(K)|2/|a1(π)|2=1.066±0.042±0.018±0.023, as well as for different particle species. The ratio is consistent with unity and therefore no evidence for SU(3) symmetry breaking effects is found at the 5% precision level
Measurement of branching fraction and direct asymmetry in charmless decays at Belle
No full textWe report a study of the charmless hadronic decay of the charged meson to the three-body final state . The results are based on a data sample that contains pairs collected at the resonance with the Belle detector at the KEKB asymmetric-energy collider. The measured inclusive branching fraction and the direct asymmetry are and , respectively, where the first uncertainties are statistical and the second are systematic. The invariant mass distribution of the signal candidates shows an excess in the region below GeV/, which is consistent with the previous studies from BaBar and LHCb. In addition, strong evidence of a large direct asymmetry is found in the low-invariant-mass region
Measurement of asymmetries in decays at Belle II
No full textWe report a measurement of decay-time dependent charge-parity () asymmetries in decays. We use pairs collected at the resonance with the Belle II detector at the SuperKEKB asymmetric-energy electron-positron collider. We reconstruct 220 signal events and extract the -violating parameters and from a fit to the distribution of the decay-time difference between the two mesons. The resulting confidence region is consistent with previous measurements in and decays, and with predictions based on the standard model
Angular analysis of the low K+K− invariant mass enhancement in B+→K+K−π+ decays
No full textWe study the decay B+→K+K−π+ and investigate the angular distribution of K+K− pairs with invariant mass below 1.1 GeV/c2. This region exhibits both a strong enhancement in signal and very large direct CP violation. We construct a coherent sum model for the angular distribution of S- and P-wave, and report the ratio of their amplitudes, the relative phase and the forward-backward asymmetry. We also report absolute differential branching fractions and direct CP asymmetry for the decay in bins of MK+K− and the differential branching fractions in bins of MK+π−. The results are based on a data sample that contains 772×10^6 BB ̄ pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider. The measured overall branching fraction and the direct CP asymmetry are (5.38±0.40±0.35)×10^−6 and −0.170±0.073±0.017, respectively, where the first uncertainties are statistical and the second are systematic
Search for the highly suppressed decays B- -> K+π-π- and B- -> K-K-π+
No full textWe report a search for the decays B- -> K+pi(-)pi(-) and B- -> K-K-pi(+), which are highly suppressed in the standard model. Using a sample of (467 +/- 5) x 10(6) B (B) over bar pairs collected with the BABAR detector, we do not see any evidence of these decays and determine 90% confidence level upper limits of B(B- -> K+pi(-)pi(-)) and K-K-pi(+)) and < 1.6 x 10(-7) on the corresponding branching fractions, including systematic uncertainties
Evidence for Direct CP Violation in B-+/- -> eta h(+/-) and Observation of B-0 -> eta K-0
No full textWe report measurements of the branching fractions and CP asymmetries for B-+/- -> eta h(+/-) (h = K or pi) and the observation of the decay B-0 -> eta K-0 from the final data sample of 772 x 10(6) B (B) over bar pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The measured branching fractions are B(B-+/- -> eta K-+/-) = (2.12 +/- 0.23 +/- 0.11) x 10(-6), B(B-+/- -> eta pi(+/-)) = (4.07 +/- 0.26 +/- 0.21) x 10(-6), and B(B-0 -> eta K-0) = (1.27(-0.29)(+0.33) +/- 0.08) x 10(-6), where the last decay is observed for the first time with a significance of 5.4 standard deviations (sigma). We also find evidence for CP violation in the charged B modes, A(CP)(B-+/- -> eta K-+/-) = -0.38 +/- 0.11 +/- 0.01 and A(CP)(B-+/- -> eta pi(+/-)) = -0.19 +/- 0.06 +/- 0.01 with significances of 3.8 sigma and 3.0 sigma, respectively. For all measurements, the first and second uncertainties are statistical and systematic, respectively.LPH
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