17 research outputs found
Effects of graphene oxide nanofilm and chicken embryo muscle extract on muscle progenitor cell differentiation and contraction
Finding an effective muscle regeneration technique is a priority for regenerative medicine. It is known that the key factors determining tissue formation include cells, capable of proliferating and/or differentiating, a niche (surface) allowing their colonization and growth factors. The interaction between these factors, especially between the surface of the artificial niche and growth factors, is not entirely clear. Moreover, it seems that the use of a complex of complementary growth factors instead of a few strictly defined ones could increase the effectiveness of tissue maturation, including muscle tissue. In this study, we evaluated whether graphene oxide (GO) nanofilm, chicken embryo muscle extract (CEME), and GO combined with CEME would affect the differentiation and functional maturation of muscle precursor cells, as well as the ability to spontaneously contract a pseudo-tissue muscle. CEME was extracted on day 18 of embryogenesis. Muscle cells obtained from an 8-day-old chicken embryo limb bud were treated with GO and CEME. Cell morphology and differentiation were observed using different microscopy methods. Cytotoxicity and viability of cells were measured by lactate dehydrogenase and Vybrant Cell Proliferation assays. Gene expression of myogenic regulatory genes was measured by Real-Time PCR. Our results demonstrate that CEME, independent of the culture surface, was the main factor influencing the intense differentiation of muscle progenitor cells. The present results, for the first time, clearly demonstrated that the cultured tissue-like structure was capable of inducing contractions without externally applied impulses. It has been indicated that a small amount of CEME in media (about 1%) allows the culture of pseudo-tissue muscle capable of spontaneous contraction. The study showed that the graphene oxide may be used as a niche for differentiating muscle cells, but the decisive influence on the maturation of muscle tissue, especially muscle contractions, depends on the complexity of the applied growth factors
From crystal phase mixture to pure metal-organic frameworks : tuning pore and structure properties
Titanium dioxide doped with vanadium as effective catalyst for selective oxidation of diphenyl sulfide to diphenyl sulfonate
Nowe nanotlenkowe katalizatory do reakcji uwodornienia CO2
The increasing concentration of CO2 in the atmosphere, which is considered to be one of the anthropogenic sources of global warming, increased concerns and social awareness about the climate change. The strategies for CO2 emissions reduction may be divided into (i) carbon capture and storage (CCS) and (ii) carbon capture and utilization (CCU) groups. In comparison to CCS, the CCU technologies allow to convert carbon dioxide into a valuable product. Thus, CCU methods are treating CO2 as raw material and not as pollutant. Among the processes that convert CO2 into a valuable compound is carbon dioxide methanation. In this process carbon dioxide is hydrogenated to methane with hydrogen supplied via water electrolysis using e.g. excess energy. It should be mentioned that some industrial scale installation already exists (up to 10MW). The literature study suggests that the most appropriate active metal in this process is nickel due to (i) very good catalytic activity (comparable to noble metals), (ii) low cost and (iii) availability. As reported in literature, different strategies were implemented in order to increase the activity of Ni-based catalysts in CO2 methanation. The most common ones include using various supports, changing the content of nickel or introduction of promoters. These strategies change the physicochemical properties, such as interaction of nickel active phase with the support, which inhibits sintering and increases the CO2 adsorption capacity. The latter property , as well as stability towards sintering, are crucial in order to obtain an active, selective and stable catalyst for CO2 methanation reaction. The application of mixed oxides of magnesia and alumina allows to introduce these properties, as MgO possesses basic character and is strongly bonded with NiO due to the formation of a solid solution of NiO-MgO. Hydrotalcites seem to be the highly promising materials for such application, because NiO, MgO and Al2O3 may be easily introduced into such materials. Literature studies confirmed that Ni-containing hydrotalcites are very active in CO2 methanation. Therefore, the goal of this PhD thesis was to evaluate the catalytic properties of Ni-containing hydrotalcite-derived mixed oxide materials in CO2 methanation. As the literature review showed that there are not many studies focused on such materials in the mentioned field, this work was focused on filling these gaps. The work was divided into four parts: (i) evaluation of catalytic properties of hydrotalcites containing various amounts of nickel in brucite-like layers, (ii) evaluation of catalytic properties of nickel-containing hydrotalcites promoted with Fe or La, (iii) evaluation of the effect of different methods of introduction of La on catalytic properties of Ni-hydrotalcites, and (iv) optimization of the catalysts and examination of promoting effect of La. In order to correlate the changes of physico-chemical properties, of the materials prepared by co-precipitation, the catalysts were characterized by means of elemental analysis (ICP-MS or XRF), XRD, FTIR, low temperature nitrogen sorption, H2-TPR and CO2-TPD. Additionally, selected catalysts were characterized using TEM, XANES and XES. The catalytic tests were carried out in the temperature range from 250°C to 450°C. In order to elucidate the promoting effect of lanthanum introduction operando XANES and XES under various reaction conditions were implemented. (...)Lâaugmentation de la concentration de CO2 dans l'atmosphĂšre, considĂ©rĂ©e comme l'une des sources anthropiques du rĂ©chauffement de la planĂšte, suscite de plus en plus d'inquiĂ©tudes et une prise de conscience sociale face au changement climatique. Les stratĂ©gies de rĂ©duction des Ă©missions de CO2 peuvent ĂȘtre divisĂ©es en deux groupes (i) capture et stockage du carbone (CCS) et (ii) capture et utilisation du carbone (CCU). En comparaison avec le CCS, les technologies CCU permettent de convertir le dioxyde de carbone en un produit valorisĂ©. Ainsi, les mĂ©thodes CCU traitent le CO2 en tant que matiĂšre premiĂšre et non en tant que polluant. Parmi les processus convertissant le CO2 en un composĂ© valorisĂ©, on trouve la mĂ©thanation du dioxyde de carbone. Dans ce processus, le dioxyde de carbone est hydrogĂ©nĂ© en mĂ©thane Ă lâaide de l'hydrogĂšne provenant de lâĂ©lectrolyse de l'eau en utilisant par exemple des excĂšs d'Ă©nergie. Il convient de mentionner quâune installation Ă lâĂ©chelle industrielle existe dĂ©jĂ (jusquâĂ 10 MW). La littĂ©rature suggĂšre que le nickel est le mĂ©tal actif le plus appropriĂ© dans ce procĂ©dĂ© en raison de (i) sa trĂšs bonne activitĂ© catalytique (comparable aux mĂ©taux nobles), (ii) un faible coĂ»t et (iii) une grande disponibilitĂ©. Dans la littĂ©rature, diffĂ©rentes stratĂ©gies ont dĂ©jĂ Ă©tĂ© mises en Ćuvre afin d'accroĂźtre l'activitĂ© des catalyseurs Ă base de Ni lors de la mĂ©thanation du CO2. Les plus courants incluent lâutilisation de divers supports, la modification de la teneur en nickel ou lâintroduction de promoteurs. De telles stratĂ©gies modifient les propriĂ©tĂ©s physicochimiques telles que l'interaction entre la phase active au nickel et le support, ce qui inhibe le frittage et augmente la capacitĂ© d'adsorption du CO2. Ces deux propriĂ©tĂ©s sont essentielles afin dâobtenir un catalyseur Ă la fois actif et sĂ©lectif pour la mĂ©thanation du CO2. Lâapplication dâoxydes mixtes de magnĂ©sie et dâalumine permet dâintroduire ces propriĂ©tĂ©s car le MgO possĂšde un caractĂšre basique et est fortement liĂ© au NiO en raison de la formation dâune solution solide de NiO-MgO. Les hydrotalcites semblent ĂȘtre les matĂ©riaux les plus prometteurs pour une telle application car NiO, MgO et Al2O3 peuvent ĂȘtre facilement introduits dans ceux-ci. La littĂ©rature a confirmĂ© que les hydrotalcites contenant du Ni sont trĂšs actifs dans cette rĂ©action. L'objectif de cette thĂšse Ă©tait donc d'Ă©valuer les propriĂ©tĂ©s catalytiques d'oxydes mixtes dĂ©rivĂ©s d'hydrotalcite contenant du Ni lors de la mĂ©thanation du CO2. Comme la revue de littĂ©rature a montrĂ© qu'il y avait peu d'Ă©tudes sur de tels matĂ©riaux pour cette rĂ©action, ces travaux ont servi Ă combler ces lacunes. Ces travaux peuvent ĂȘtre divisĂ© en quatre parties : (i) Ă©valuation des propriĂ©tĂ©s catalytiques dâhydrotalcites contenant diverses quantitĂ©s de nickel dans des couches de type brucite, (ii) Ă©valuation des propriĂ©tĂ©s catalytiques dâhydrotalcites contenant du nickel activĂ©es Ă l'aide de Fe ou de La, (iii) Ă©valuation de l'effet de la mĂ©thode d'introduction de La sur les propriĂ©tĂ©s catalytiques des Ni-hydrotalcites et (iv) optimisation des catalyseurs et examen de l'effet promoteur de La. Afin de corrĂ©ler les modifications des propriĂ©tĂ©s physico-chimiques des matĂ©riaux prĂ©parĂ©s par co-prĂ©cipitation, les catalyseurs ont Ă©tĂ© caractĂ©risĂ©s par analyse Ă©lĂ©mentaire (ICP-MS ou XRF), DRX, IRTF, sorption de lâazote Ă basse tempĂ©rature, H2-TPR et CO2-TPD. De plus, les catalyseurs sĂ©lectionnĂ©s ont Ă©tĂ© caractĂ©risĂ©s par TEM, XANES et XES. Les tests catalytiques ont Ă©tĂ© effectuĂ©s dans une plage de tempĂ©ratures allant de 250°C Ă 450°C. Afin d'examiner l'effet de promotion de l'introduction du lanthane, les mĂ©thodes XANES et XES dans diverses conditions de rĂ©action ont Ă©tĂ© mises en Ćuvre. (...
Nowe nanotlenkowe katalizatory do reakcji uwodornienia CO2
Lâaugmentation de la concentration de CO2 dans l'atmosphĂšre, considĂ©rĂ©e comme l'une des sources anthropiques du rĂ©chauffement de la planĂšte, suscite de plus en plus d'inquiĂ©tudes et une prise de conscience sociale face au changement climatique. Les stratĂ©gies de rĂ©duction des Ă©missions de CO2 peuvent ĂȘtre divisĂ©es en deux groupes (i) capture et stockage du carbone (CCS) et (ii) capture et utilisation du carbone (CCU). En comparaison avec le CCS, les technologies CCU permettent de convertir le dioxyde de carbone en un produit valorisĂ©. Ainsi, les mĂ©thodes CCU traitent le CO2 en tant que matiĂšre premiĂšre et non en tant que polluant. Parmi les processus convertissant le CO2 en un composĂ© valorisĂ©, on trouve la mĂ©thanation du dioxyde de carbone. Dans ce processus, le dioxyde de carbone est hydrogĂ©nĂ© en mĂ©thane Ă lâaide de l'hydrogĂšne provenant de lâĂ©lectrolyse de l'eau en utilisant par exemple des excĂšs d'Ă©nergie. Il convient de mentionner quâune installation Ă lâĂ©chelle industrielle existe dĂ©jĂ (jusquâĂ 10 MW). La littĂ©rature suggĂšre que le nickel est le mĂ©tal actif le plus appropriĂ© dans ce procĂ©dĂ© en raison de (i) sa trĂšs bonne activitĂ© catalytique (comparable aux mĂ©taux nobles), (ii) un faible coĂ»t et (iii) une grande disponibilitĂ©. Dans la littĂ©rature, diffĂ©rentes stratĂ©gies ont dĂ©jĂ Ă©tĂ© mises en Ćuvre afin d'accroĂźtre l'activitĂ© des catalyseurs Ă base de Ni lors de la mĂ©thanation du CO2. Les plus courants incluent lâutilisation de divers supports, la modification de la teneur en nickel ou lâintroduction de promoteurs. De telles stratĂ©gies modifient les propriĂ©tĂ©s physicochimiques telles que l'interaction entre la phase active au nickel et le support, ce qui inhibe le frittage et augmente la capacitĂ© d'adsorption du CO2. Ces deux propriĂ©tĂ©s sont essentielles afin dâobtenir un catalyseur Ă la fois actif et sĂ©lectif pour la mĂ©thanation du CO2. Lâapplication dâoxydes mixtes de magnĂ©sie et dâalumine permet dâintroduire ces propriĂ©tĂ©s car le MgO possĂšde un caractĂšre basique et est fortement liĂ© au NiO en raison de la formation dâune solution solide de NiO-MgO. Les hydrotalcites semblent ĂȘtre les matĂ©riaux les plus prometteurs pour une telle application car NiO, MgO et Al2O3 peuvent ĂȘtre facilement introduits dans ceux-ci. La littĂ©rature a confirmĂ© que les hydrotalcites contenant du Ni sont trĂšs actifs dans cette rĂ©action. L'objectif de cette thĂšse Ă©tait donc d'Ă©valuer les propriĂ©tĂ©s catalytiques d'oxydes mixtes dĂ©rivĂ©s d'hydrotalcite contenant du Ni lors de la mĂ©thanation du CO2. Comme la revue de littĂ©rature a montrĂ© qu'il y avait peu d'Ă©tudes sur de tels matĂ©riaux pour cette rĂ©action, ces travaux ont servi Ă combler ces lacunes. Ces travaux peuvent ĂȘtre divisĂ© en quatre parties : (i) Ă©valuation des propriĂ©tĂ©s catalytiques dâhydrotalcites contenant diverses quantitĂ©s de nickel dans des couches de type brucite, (ii) Ă©valuation des propriĂ©tĂ©s catalytiques dâhydrotalcites contenant du nickel activĂ©es Ă l'aide de Fe ou de La, (iii) Ă©valuation de l'effet de la mĂ©thode d'introduction de La sur les propriĂ©tĂ©s catalytiques des Ni-hydrotalcites et (iv) optimisation des catalyseurs et examen de l'effet promoteur de La. Afin de corrĂ©ler les modifications des propriĂ©tĂ©s physico-chimiques des matĂ©riaux prĂ©parĂ©s par co-prĂ©cipitation, les catalyseurs ont Ă©tĂ© caractĂ©risĂ©s par analyse Ă©lĂ©mentaire (ICP-MS ou XRF), DRX, IRTF, sorption de lâazote Ă basse tempĂ©rature, H2-TPR et CO2-TPD. De plus, les catalyseurs sĂ©lectionnĂ©s ont Ă©tĂ© caractĂ©risĂ©s par TEM, XANES et XES. Les tests catalytiques ont Ă©tĂ© effectuĂ©s dans une plage de tempĂ©ratures allant de 250°C Ă 450°C. Afin d'examiner l'effet de promotion de l'introduction du lanthane, les mĂ©thodes XANES et XES dans diverses conditions de rĂ©action ont Ă©tĂ© mises en Ćuvre. (...)The increasing concentration of CO2 in the atmosphere, which is considered to be one of the anthropogenic sources of global warming, increased concerns and social awareness about the climate change. The strategies for CO2 emissions reduction may be divided into (i) carbon capture and storage (CCS) and (ii) carbon capture and utilization (CCU) groups. In comparison to CCS, the CCU technologies allow to convert carbon dioxide into a valuable product. Thus, CCU methods are treating CO2 as raw material and not as pollutant. Among the processes that convert CO2 into a valuable compound is carbon dioxide methanation. In this process carbon dioxide is hydrogenated to methane with hydrogen supplied via water electrolysis using e.g. excess energy. It should be mentioned that some industrial scale installation already exists (up to 10MW). The literature study suggests that the most appropriate active metal in this process is nickel due to (i) very good catalytic activity (comparable to noble metals), (ii) low cost and (iii) availability. As reported in literature, different strategies were implemented in order to increase the activity of Ni-based catalysts in CO2 methanation. The most common ones include using various supports, changing the content of nickel or introduction of promoters. These strategies change the physicochemical properties, such as interaction of nickel active phase with the support, which inhibits sintering and increases the CO2 adsorption capacity. The latter property , as well as stability towards sintering, are crucial in order to obtain an active, selective and stable catalyst for CO2 methanation reaction. The application of mixed oxides of magnesia and alumina allows to introduce these properties, as MgO possesses basic character and is strongly bonded with NiO due to the formation of a solid solution of NiO-MgO. Hydrotalcites seem to be the highly promising materials for such application, because NiO, MgO and Al2O3 may be easily introduced into such materials. Literature studies confirmed that Ni-containing hydrotalcites are very active in CO2 methanation. Therefore, the goal of this PhD thesis was to evaluate the catalytic properties of Ni-containing hydrotalcite-derived mixed oxide materials in CO2 methanation. As the literature review showed that there are not many studies focused on such materials in the mentioned field, this work was focused on filling these gaps. The work was divided into four parts: (i) evaluation of catalytic properties of hydrotalcites containing various amounts of nickel in brucite-like layers, (ii) evaluation of catalytic properties of nickel-containing hydrotalcites promoted with Fe or La, (iii) evaluation of the effect of different methods of introduction of La on catalytic properties of Ni-hydrotalcites, and (iv) optimization of the catalysts and examination of promoting effect of La. In order to correlate the changes of physico-chemical properties, of the materials prepared by co-precipitation, the catalysts were characterized by means of elemental analysis (ICP-MS or XRF), XRD, FTIR, low temperature nitrogen sorption, H2-TPR and CO2-TPD. Additionally, selected catalysts were characterized using TEM, XANES and XES. The catalytic tests were carried out in the temperature range from 250°C to 450°C. In order to elucidate the promoting effect of lanthanum introduction operando XANES and XES under various reaction conditions were implemented. (...
A Proposal Concerning Assessment of Alternative Cityscape Designs with Audiovisual Comfort and Health of Inhabitants
The research concerning the future of sound in towns and cities is focused on two main issues: studies are conducted separately on the comfort, i.e., assessment of visual scenery and sound levels in a cityscape and separately, on the health protection issues. The policy of the acoustic environment control with regard to the health of its inhabitants is traditionally connected with measurements of noise levels presented with the help of the coefficients Lden and Lnight noise indicators, while the models based on tranquillity rating (TR) with the help of the coefficients LAmax, LAmin, LAeq, LA10. None of these coefficients refers to the soundscape. In this paper, we present a justification of the necessity to enter into discussion on the need to combine these research areas. The authorities managing towns and cities of the future should be provided with tools enabling them to assess modernisation projects from the point of view of both health and comfort of inhabitants. We present our ideas treating them as an invitation to a scientific discourse, in the form of analysis of actual projects concerning modification of existing cityscapes. The modifications are aimed at returning some unfavourably developed spaces to the inhabitants. When analysing the changes proposed in the projects, we take into account two models of the revitalised area quality assessment. The first model is used to assess the effect of noise on health. The second model, based on the indicator known as the TR, serves simultaneous assessment of an area from both visual and acoustical aspects. The models used contemporarily by scientists show multiple flaws, therefore, for the TR indicator we propose a modification taking the sound structure into account. The modification embodies the idea of masking unpleasant sounds with friendly ones. The changes to the model are presented, in this paper, in the context of two projects which were worked out in the framework of 12th edition of the intercollegiate workshop cycle The New Cityscapes. In the course of each workshop of the cycle, we combined art, science, and technology in order to seek solutions creating a better future. In view of the importance of this issue and the need to introduce a certain level of universalism, the authors offer an invitation to join a discussion on the future of sound in urban agglomerations