1,995 results on '"Synthèse"'
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2. Landschaftsökologie
- Author
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Leser, Hartmut, Kühne, Olaf, Series Editor, Kinder, Sebastian, Series Editor, Schnur, Olaf, Series Editor, Weber, Florian, editor, Berr, Karsten, editor, and Jenal, Corinna, editor
- Published
- 2024
- Full Text
- View/download PDF
3. Durchflussunterstützte Synthese von Heterocyclen über Mehrkomponentenreaktionen
- Author
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Van Mileghem, Seger, Veryser, Cedrick, De Borggraeve, Wim M., Sharma, Upendra K., editor, and Van der Eycken, Erik V., editor
- Published
- 2024
- Full Text
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4. Durchflusschemieansätze angewendet auf die Synthese von gesättigten Heterocyclen
- Author
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Baumann, Marcus, Baxendale, Ian R., Sharma, Upendra K., editor, and Van der Eycken, Erik V., editor
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- 2024
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5. Unsichtbare(s) sichtbar machen: Epistemologische Bedeutung von Frauen in der pädagogischen Theorienbildung.
- Author
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Susak, Mara
- Subjects
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WOMEN'S education , *TEACHERS , *EDUCATION research , *PHILOSOPHY of education , *EDUCATION theory - Abstract
Making the Invisible(s) Visible. Epistemological Significance of Women in Pedagogical Theorising In the tradition of pedagogical theory, women are rarely mentioned. Historical educational research should contribute to making the women pedagogues and their theories visible so that the merits and limitations of the different positions within historical pedagogy can be learned about and reflected upon. The article argues that only a synthesis of theories allows for expanded thinking. The aim is to recognise the achievements of women in historical education research on an equal footing. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. One-Pass-Entwurfsablauf
- Author
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Zulehner, Alwin, Wille, Robert, Zulehner, Alwin, and Wille, Robert
- Published
- 2023
- Full Text
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7. Übersicht
- Author
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Zulehner, Alwin, Wille, Robert, Zulehner, Alwin, and Wille, Robert
- Published
- 2023
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8. Schlussbemerkungen
- Author
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Zulehner, Alwin, Wille, Robert, Zulehner, Alwin, and Wille, Robert
- Published
- 2023
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9. Fluorine‐Containing Functional Group‐Based Energetic Materials.
- Author
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Guo, Zihao, Yu, Qiong, Chen, Yucong, Liu, Jie, Li, Tao, Peng, Yuhuang, and Yi, Wenbin
- Subjects
- *
FUNCTIONAL groups , *ENERGY density , *THERMAL stability , *FLUORINE , *ELECTRON density , *MOIETIES (Chemistry) - Abstract
Molecules featuring fluorine‐containing functional groups exhibit outstanding properties with high density, low sensitivity, excellent thermal stability, and good energetic performance due to the strong electron‐withdrawing ability and high density of fluorine. Hence, they play a pivotal role in the field of energetic materials. In light of current theoretical and experimental reports, this review systematically focuses on three types of energetic materials possessing fluorine‐containing functional groups F‐ and NF2‐ substituted trinitromethyl groups (C(NO2)2F, C(NO2)2NF2), trifluoromethyl group (CF3), and difluoroamino and pentafluorosulfone groups (NF2, SF5) and investigates the synthetic methods, physicochemical parameters, and energetic properties of each. The incorporation of fluorine‐containing functional moieties is critical for the development of novel high energy density materials, and is rapidly being adopted in the design of energetic materials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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10. A regional integrated assessment of the impacts of climate change and of the potential adaptation avenues for Quebec's forests.
- Author
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Boulanger, Yan, Puigdevall, Jesus Pascual, Bélisle, Annie Claude, Bergeron, Yves, Brice, Marie-Hélène, Cyr, Dominic, De Grandpré, Louis, Fortin, Daniel, Gauthier, Sylvie, Grondin, Pierre, Labadie, Guillemette, Leblond, Mathieu, Marchand, Maryse, Splawinski, Tadeusz B., St-Laurent, Martin-Hugues, Thiffault, Evelyne, Tremblay, Junior A., and Yamasaki, Stephen H.
- Abstract
Regional analyses assessing the vulnerabilities of forest ecosystems and the forest sector to climate change are key to considering the heterogeneity of climate change impacts as well as the fact that risks, opportunities, and adaptation capacities might differ regionally. Here we provide the Regional Integrated Assessment of climate change on Quebec's forests, a work that involved several research teams and focused on climate change impacts on Quebec's commercial forests and on potential adaptation solutions. Our work showed that climate change will alter several ecological processes within Quebec's forests. These changes will result in important modifications in forest landscapes. Harvest will cumulate with climate change effects to further alter future forest landscapes, which will also have consequences on wildlife habitats (including woodland caribou habitat), avian biodiversity, carbon budget, and a variety of forest landscape values for Indigenous peoples. The adaptation of the forest sector will be crucial to mitigate the impacts of climate change on forest ecosystem goods and services and improve their resilience. Moving forward, a broad range of adaptation measures, notably through reducing harvest levels, should be explored to help strike a balance among social, ecological, and economic values. We conclude that without climate adaptation, strong negative economic and ecological impacts will likely affect Quebec's forests. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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11. Untersuchung von Ladungstransferprozessen in einer kovalent verknüpften [Ge9]‐Cluster‐Imin Dyade.
- Author
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Wallach, Christoph, Selic, Yasmin, Geitner, Felix S., Kumar, Ajeet, Thyrhaug, Erling, Hauer, Jürgen, Karttunen, Antti J., and Fässler, Thomas F.
- Subjects
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NUNS , *DESIGN - Abstract
C60 Donor Dyaden, in denen der Kohlenstoffkäfig kovalent an eine Elektronen‐Donoreinheit gebunden vorliegt, werden als ein mögliches Elektronentransfersystem diskutiert, und es wurde gezeigt, dass kugelförmige [Ge9]‐Clusteranionen bezüglich ihrer elektronischen Struktur eng mit den Fullerenen verwandt sind. Die optischen Eigenschaften dieser Cluster und ihrer funktionalisierten Derivate sind jedoch nahezu unbekannt. Wir berichten nun über die Synthese des intensiv roten [Ge9]‐Clusters, welcher an ein ausgedehntes π‐Elektronensystem gebunden ist. [Ge9{Si(TMS)3}2{CH3C=N}‐DAB(II)Dipp]− (1−) entsteht bei der Reaktion von [Ge9{Si(TMS)3}2]2− mit Bromdiazaborol DAB(II)Dipp‐Br in CH3CN (TMS=Trimethylsilyl; DAB(II)=1,3,2‐Diazaborol mit einem ungesättigten Gerüst; Dipp=2,6‐Di‐iso‐propylphenyl). Die reversible Protonierung der Imineinheit in 1− führt zum tiefgrünen, zwitterionischen Cluster [Ge9{Si(TMS)3}2{CH3C=N(H)}‐DAB(II)Dipp] (1‐H). Optische Spektroskopie in Kombination mit zeitabhängigen Dichtefunktional‐theoretischen Berechnungen legen eine Elektronentransfer‐Anregung zwischen dem Cluster und dem antibindenden π*‐Orbital der Iminiumeinheit als Urache für die intensive Farbe nahe. Ein Absorptionsmaximum von 1‐H im roten Bereich des elektromagnetischen Spektrums und der entsprechende niedrigste angeregte Zustand bei λ=669 nm machen die Verbindung zu einem interessanten Ausgangspunkt für weitere Untersuchungen, die auf das Design photoaktiver Clusterverbindungen abzielen. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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12. Les interventions des enseignants débutants dans les copies des étudiants en droit
- Author
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Scheepers Caroline
- Subjects
annotations ,université ,résumé ,synthèse ,Social Sciences - Abstract
Ont été analysées au moyen d’un grand nombre d’indicateurs les annotations présentes dans plusieurs centaines de résumés ou de synthèses élaborés par des primoétudiants inscrits dans un bachelier en Droit. Je me suis centrée sur les pratiques évaluatives de quatre assistants, à qui ont été confiés des séminaires en sciences humaines (criminologie, sociologie, histoire contemporaine). Les analyses montrent des résultats assez divergents par rapport aux études existantes en la matière.
- Published
- 2024
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13. Winters are changing: snow effects on Arctic and alpine tundra ecosystems1
- Author
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Christian Rixen, Toke Thomas Høye, Petr Macek, Rien Aerts, Juha M. Alatalo, Jill T. Anderson, Pieter A. Arnold, Isabel C Barrio, Jarle W. Bjerke, Mats P. Björkman, Daan Blok, Gesche Blume-Werry, Julia Boike, Stef Bokhorst, Michele Carbognani, Casper T. Christiansen, Peter Convey, Elisabeth J. Cooper, J. Hans C. Cornelissen, Stephen J. Coulson, Ellen Dorrepaal, Bo Elberling, Sarah C. Elmendorf, Cassandra Elphinstone, T’ai G.W. Forte, Esther R. Frei, Sonya R. Geange, Friederike Gehrmann, Casey Gibson, Paul Grogan, Aud Helen Halbritter, John Harte, Gregory H.R. Henry, David W. Inouye, Rebecca E. Irwin, Gus Jespersen, Ingibjörg Svala Jónsdóttir, Ji Young Jung, David H. Klinges, Gaku Kudo, Juho Lämsä, Hanna Lee, Jonas J. Lembrechts, Signe Lett, Joshua Scott Lynn, Hjalte M.R. Mann, Mikhail Mastepanov, Jennifer Morse, Isla H. Myers-Smith, Johan Olofsson, Riku Paavola, Alessandro Petraglia, Gareth K. Phoenix, Philipp Semenchuk, Matthias B. Siewert, Rachel Slatyer, Marko J. Spasojevic, Katharine Suding, Patrick Sullivan, Kimberly L. Thompson, Maria Väisänen, Vigdis Vandvik, Susanna Venn, Josefine Walz, Robert Way, Jeffrey M. Welker, Sonja Wipf, and Shengwei Zong
- Subjects
review ,tundra ,ground temperatures ,snow experiments ,ITEX ,synthèse ,Environmental sciences ,GE1-350 ,Environmental engineering ,TA170-171 - Abstract
Snow is an important driver of ecosystem processes in cold biomes. Snow accumulation determines ground temperature, light conditions, and moisture availability during winter. It also affects the growing season’s start and end, and plant access to moisture and nutrients. Here, we review the current knowledge of the snow cover’s role for vegetation, plant-animal interactions, permafrost conditions, microbial processes, and biogeochemical cycling. We also compare studies of natural snow gradients with snow experimental manipulation studies to assess time scale difference of these approaches. The number of tundra snow studies has increased considerably in recent years, yet we still lack a comprehensive overview of how altered snow conditions will affect these ecosystems. Specifically, we found a mismatch in the timing of snowmelt when comparing studies of natural snow gradients with snow manipulations. We found that snowmelt timing achieved by snow addition and snow removal manipulations (average 7.9 days advance and 5.5 days delay, respectively) were substantially lower than the temporal variation over natural spatial gradients within a given year (mean range 56 days) or among years (mean range 32 days). Differences between snow study approaches need to be accounted for when projecting snow dynamics and their impact on ecosystems in future climates.
- Published
- 2022
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14. Impact of climate change on catchment nutrient dynamics: insights from around the world.
- Author
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Costa, Diogo, Sutter, Caleb, Shepherd, Anita, Jarvie, Helen, Wilson, Henry, Elliott, Jane, Liu, Jian, and Macrae, Merrin
- Abstract
This study is a meta-analysis of global articles on hydrological nutrient dynamics to determine trends and consensus on: (1) the effects of climate change-induced hydrological and temperature drivers on nutrient dynamics and how these effects vary along the catchment continuum from land to river to lake; (2) the convergence of climate change impacts with other anthropogenic pressures (agriculture, urbanization) in nutrient dynamics; and (3) regional variability in the effects of climate change on nutrient dynamics and water-quality impairment across different climate zones. An innovative web crawler tool was employed to help critically synthesize the information in the literature. The literature suggests that climate change will impact nutrient dynamics around the globe and exacerbate contemporary water-quality challenges. Nutrient leaching and overland flow transport are projected to increase globally, promoted by extreme precipitation. Seasonal variations in streamflow are expected to emulate changing precipitation patterns, but the specific local impacts of climate change on hydrology and nutrient dynamics will vary both seasonally and regionally. Plant activity may reduce some of this load in nonagricultural soils if the expected increase in plant uptake of nutrients prompted by increased temperatures can compensate for greater nitrogen (N) and phosphorus (P) mineralization, N deposition, and leaching rates. High-temperature forest and grass fires may help reduce mineralization and microbial turnover by altering N speciation via the pyrolysis of organic matter. In agricultural areas that are at higher risk of erosion, extreme precipitation will exacerbate existing water-quality issues, and greater plant nutrient uptake may lead to an increase in fertilizer use. Future urban expansion will amplify these effects. Higher ambient temperatures will promote harmful cyanobacterial blooms by enhancing thermal stratification, increasing nutrient load into streams and lakes from extreme precipitation events, decreasing summer flow and thus baseflow dilution capacity, and increasing water and nutrient residence times during increasingly frequent droughts. Land management decisions must consider the nuanced regional and seasonal changes identified in this review (realized and predicted). Such knowledge is critical to increasing international cooperation and accelerating action toward the United Nations's global sustainability goals and the specific objectives of the Conference of Parties (COP) 26. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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15. Motivating Corporate Sustainability Research in Management Accounting Through the Lens of Paradox Theory*.
- Author
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Pencle, Nadra
- Subjects
CORPORATE sustainability ,MANAGERIAL accounting ,SUSTAINABLE development reporting ,PARADOX ,MANAGEMENT accountants ,CORPORATE accounting - Abstract
Copyright of Accounting Perspectives is the property of Canadian Academic Accounting Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
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16. Applying systemic functional linguistics in translation studies: A research synthesis.
- Author
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Chen, Shukun, Xuan, Winfred Wenhui, and Yu, Hailing
- Subjects
- *
FUNCTIONAL linguistics , *META-analysis , *CONTENT analysis , *RESEARCH , *TRANSLATIONS - Abstract
This paper takes a meta-analysis and synthesis approach to emphasize systemic functional linguistics' contribution to translation studies. A coding book was designed to analyze 123 studies collected through email inquiry, database search, and manual examination. The paper reports on the substantive features and methodological features of the studies. Content analysis was presented on four major research themes: general translation, genre translation, interpreting, and translation training. After discussing the synthesis results, the paper is concluded with implications for future research. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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17. Le Centre de collaboration nationale des méthodes et outils (CCNMO) : soutenir la prise de décisions fondée sur des données probantes en santé publique au Canada
- Author
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Heather Husson, Claire Howarth, Sarah Neil-Sztramko, and Maureen Dobbins
- Subjects
santé publique ,données probantes ,synthèse ,mobilisation des connaissances ,partenariat ,réseaux ,covid-19 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Le Centre de collaboration nationale des méthodes et outils (CCNMO) fait partie d’un réseau de six centres de collaboration nationale en santé publique (CCN) créé en 2005 par le gouvernement fédéral à la suite de l’épidémie de syndrome respiratoire aigu sévère (SRAS) afin de renforcer l’infrastructure de la santé publique au Canada. Le travail du CCNMO, qui vise à soutenir la prise de décisions fondée sur des données probantes dans le domaine de la santé publique au Canada, est accompli par l’organisation des données probantes dignes de confiance, le renforcement des compétences dans l’utilisation des données probantes, et l’accélération du changement dans la prise de décisions fondée sur des données probantes est décrit. La consultation permanente auprès de ses publics cibles garantit la pertinence du CCNMO et sa capacité à répondre à l’évolution des besoins en matière de santé publique. Cela s’est avéré particulièrement crucial lors de la pandémie de maladie à coronavirus 2019 (COVID-19). Le CCNMO a alors modifié la direction de ses activités pour soutenir l’intervention de la santé publique en effectuant des revues rapides sur les questions prioritaires identifiées par les décideurs, à l’échelle fédérale ou à l’échelle locale, ainsi qu’en créant et en maintenant un répertoire national de synthèses en cours ou terminées. Ces efforts, ainsi que le partenariat avec le COVID-19 Evidence Network to support Decision-Making (COVID-END), visaient à réduire les doublons, à accroître la coordination des efforts de synthèse et à aider les décideurs à utiliser les meilleures données probantes dont on dispose dans la prise de décisions. Les données tirées des statistiques du site Web illustrent le succès de ces initiatives au Canada et à l’étranger.
- Published
- 2021
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18. Ein persistentes phosphanyl‐substituiertes Thioketylradikalanion.
- Author
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Szych, Lilian Sophie, Pilopp, Yannic, Bresien, Jonas, Villinger, Alexander, Rabeah, Jabor, and Schulz, Axel
- Subjects
- *
ANIONS - Abstract
Alkalimetallsalze des Typs M+[Ter(iPr)P−C(=S)−P(iPr)2S].− (M=Na, K; 2_M; Ter=2,6‐bis‐(2,4,6‐trimethylphenyl)phenyl) mit einem raumtemperaturstabilen Thioketylradikalanion wurden durch die Reduktion des Thioketons Ter(iPr)P−C(=S)−P(iPr)2S (1) mit Alkalimetallen (Na, K) erhalten. Einkristall‐Röntgenstrukturanalyse sowie ESR‐Spektroskopie konnten das Vorliegen des Thioketylradikalanions sowohl im Festkörper als auch in Lösung eindeutig zeigen. Die berechnete Mulliken‐Spindichte in 2_M ist hauptsächlich am Schwefel (49 %) sowie am Carbonyl‐Kohlenstoffatom (33 %) lokalisiert. Nach Zugabe von [2.2.2]Kryptand zur Radikalverbindung 2_K, um die interionische Wechselwirkung abzuschwächen, wurde eine Aktivierungsreaktion beobachtet, die durch intermolekulare Umlagerung einer iPr‐Gruppe von einem zweiten Anion zu einem Kaliumsalz eines Phosphanylthioether‐basierten Anions, [K(crypt)]+[Ter(iPr)P−C(−S‐iPr)−P(iPr)2S]− (3), führte. Die Produkte wurden vollständig charakterisiert und die Nutzung des Radikalanions als Reduktionsmittel wurde demonstriert. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
19. Brønstedsäure‐Zentren in Zeolith SSZ‐42 werden von Wasserstoffbrücken dominiert – eine Einteilung ihrer Vielfalt.
- Author
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Schroeder, Christian, Zones, Stacey I., Hansen, Michael Ryan, and Koller, Hubert
- Subjects
- *
BRONSTED acids - Abstract
Der Zeolithkatalysator SSZ‐42 besitzt einen außerordentlich hohen Anteil von Wasserstoff‐verbrückten Brønstedsäure‐Zentren (Brønsted acid sites, BAS) von ≈80 %, deren 1H chemische Verschiebung verglichen mit unverbrückten BAS (bei typischerweise 4 ppm) stärker entschirmt ist. Dies kommt durch die Wechselwirkung aufgrund einer günstigen Ausrichtung zu benachbarten Sauerstoffatomen des Zeolithgerüsts zustande. Eine Einteilung der Vielfalt der Wasserstoffbrücken wurde durch DFT‐Rechnungen beleuchtet, wobei 5‐Ringe und ovale 6‐Ringe zu stärkeren Wasserstoffbrücken zwischen entgegengesetzten Seiten der Ringe führen (höhere experimentelle Verschiebung, δ(1H)=6.4 ppm) als kreisförmige 6‐Ringe (δ(1H)=5.2 ppm). Käfigartige Strukturen und intra‐tetraedrische Wechselwirkungen können ebenfalls zu Wasserstoffbrücken führen. Es ist zu erwarten, dass die Ausrichtung von Sauerstoffatomen deren Rolle bei der Stabilisierung von katalytischen Zwischenprodukten beeinflussen, wie Oberflächen‐Alkoxy‐Gruppen und möglicherweise auch Übergangszustände. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. A função sintética do Eu e seus impasses na teoria freudiana.
- Author
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Gaio Filla, Munique
- Subjects
- *
NEUROSES , *NARCISSISM , *DUALISM , *AMBIGUITY , *TOPOGRAPHY - Abstract
This article aims to address the synthetic function of the Ego and the impasses inherent to its full realization, considering the ambiguity that such an instance carries in Freud’s writings. Firstly, the idea that psychoneuroses result from a case of irreconcilability between sexual representations and the Ego will be resumed, in order to explain the problems resulting from the fact that certain psychic contents do not harmonize with the latter. Second, the concept of narcissism will be recovered, since in this context Freud conceives the Ego as a unit that needs to be constituted. Finally, in the main part of this essay the synthetic function that Freud attributes to the Ego in the context of the second psychic topography and the second drive dualism will be approached. At the same time that the stamp of the Ego is its tendency to synthesis, it constantly fails and leads to pathology. This is related to the fact that this instance operates not only in favor of life drives and binding activities, but also of death drives and his search for unbinding, which, in its turn, affects the direction of freudian’s conception of the clinic. [ABSTRACT FROM AUTHOR]
- Published
- 2022
21. Le futur du travail en agriculture.
- Author
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Dedieu, Benoît
- Abstract
We present a summary of the discussions held during the 2nd International Symposium on Work in Agriculture (March 29–April 1, 2021). The objective of the paper is to report on the themes and ideas exchanged, in a multidisciplinary framework, and to build a common vision of the future of agricultural work on a global scale. The dynamics of agricultural development, on the scale of continents, oppose northern and southern countries, raising different questions (for example agriculture without farmers in northern countries versus decent work for a large agricultural working population in southern countries). But some issues are cross-cutting: the agroecological transition, gender issues, the digital revolution, migration, are changing agricultural work in depth. We propose some perspectives for a research agenda to address the future of work in agriculture. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
22. Stadtökologie
- Author
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Leser, Hartmut, Kühne, Olaf, Series Editor, Kinder, Sebastian, Series Editor, Schnur, Olaf, Series Editor, Weber, Florian, editor, Berr, Karsten, editor, and Jenal, Corinna, editor
- Published
- 2019
- Full Text
- View/download PDF
23. Landschaftsökologie
- Author
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Leser, Hartmut, Kühne, Olaf, Series Editor, Kinder, Sebastian, Series Editor, Schnur, Olaf, Series Editor, Weber, Florian, editor, Berr, Karsten, editor, and Jenal, Corinna, editor
- Published
- 2019
- Full Text
- View/download PDF
24. Preparation and Performance Evaluation of Gemini Sulphobetaine Surfactant Bis{[(N-methyl-N-(3-alkoxy-2-hydroxy) propyl-N-(3-sulfonic) propyl] methylene}.
- Author
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Zhonghua Zuo, Ming Zhou, Mao Liao, Pengao Peng, and Jingfeng Zhang
- Abstract
Surfactants are very often used in tertiary oil production. However, the conventional surfactants cannot be used in high salinity reservoirs of tertiary oil production because the high salinity leads to the deactivation of the surfactants. Gemini sulpho-betaine surfactants have been developed to meet the requirements of tertiary oil production in such reservoirs. In this study, the Gemini sulphobetaine surfactant (bis{[(N-methyl-N-(3-alkoxy-2-hydroxy)propyl-N-(3-sulfonate)propyl]methylene}) was prepared by etherification, ring opening reaction and sulfonation reaction with decyl alcohol, epichlorohydrin, N,N'-dimethyl ethylene diamine and 1,3-propanesultone. The experimental conditions obtained are: the ratio of 1,3-propanesulfonic acid lactone to tertiary amine intermediate = 2.3: 1, reaction temperature = 70°C and reaction time = 11 h. The analysis of the infrared spectrum showed that the structure of the synthesised substance corresponds to that of a Gemini sulphobetaine surfactant. The chemical shifts of the groups were determined by 1HNMR structural characterisation of the products. The surface tension, emulsifying properties, foaming properties and wetting properties were investigated. The results showed that the surfactant has good foaming properties and good compatibility in a high salt environment. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
25. Synthesis and Characterization of an Amphoteric Asphalt Emulsifier.
- Author
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Laishun Shi, Tong Ji, Jingqiu Ma, Xiaomeng Yu, and Yawen Chen
- Abstract
A novel amphoteric asphalt emulsifier of octadecylbis(propanamide)-(3'-sodium phosphate-2'-hydroxypropyl)ammonium chloride was synthesised from the raw materials octadecylamine, acrylamide, epichlorohydrin and sodium dihydrogen phosphate. The tertiary amine octadecyl-bis(propanamide) was synthesised from octadecylamine and acrylamide (step 1). Sodium 3-chloro-2-hydroxypropyl phosphate (intermediate) was obtained from epichlorohydrin and sodium dihydrogen phosphate (step 2). The asphalt emulsifier was obtained from octadecyl-bis(propanamide)-tertiary amine and the intermediate by quaternisation reaction (step 3). The yield of the final product reached 94.90%. The structure was identified by FTIR, 1H-NMR and elemental analysis. The critical micelle concentration of the product is 1.46 × 10-5 mol L-1. The surface tension at CMC is 37.78 mN ν-1. The saturated adsorption amount of asphalt emulsifier is 2.72 × 10-3 mmol ν-2. The occupied area per asphalt emulsifier molecule at CMC is 0.611 nm² mol-1. The surfactant is a fast-setting asphalt emulsifier. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
26. Fettsäuren und Fettsäurederivate als nachwachsende Plattformmoleküle für die chemische Industrie.
- Author
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Biermann, Ursula, Bornscheuer, Uwe T., Feussner, Ivo, Meier, Michael A. R., and Metzger, Jürgen O.
- Subjects
- *
OXIDATION , *ENZYMES - Abstract
Pflanzliche und tierische Öle und Fette bleiben ein wichtiger nachwachsender Rohstoff der chemischen Industrie. Ihre industrielle Nutzung hat sich in den letzten 10 Jahren von 31 auf 51 Millionen Tonnen pro Jahr erhöht. Dieser Aufsatz fasst die bedeutenden Fortschritte zusammen, die in dieser Zeit in der Oleochemie erzielt wurden, beispielsweise die Reduktion von Fettsäureestern zu Ethern, die selektive Oxidation und oxidative Spaltung von C‐C‐Doppelbindungen, die Synthese von alkylverzweigten Fettstoffen, die isomerisierende Hydroformylierung und Alkoxycarbonylierung sowie die Olefinmetathese. Auch die Nutzung von fettsäurebasierten Chemikalien in der Synthese einer Vielzahl polymerer Materialien hat stark zugenommen. Zusätzlich zu Lipasen und Phospholipasen haben mittlerweile viele weitere Enzyme in der biokatalytischen Fettchemie Anwendung gefunden. Wichtige Entwicklungen haben außerdem neue Eigenschaften bei den Ölen bestehender Nutzpflanzen hervorgebracht, was alternativ auch durch die Verwendung von metabolisch optimierten Mikroorganismen möglich ist. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
27. Thymolblau – schulische Synthese & AR‐gestützte Lernmaterialien.
- Author
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Tschiersch, Anja, Banerji, Amitabh, and Remus, Ludger
- Subjects
- *
TEACHER training , *AUGMENTED reality , *THYMOL - Abstract
This article presents the synthesis of thymol blue as a student experiment together with suitable augmented reality (AR) learning materials. In addition, the theoretical background on the synthesis of thymol blue and its pH‐dependent structure‐property relationship is discussed with regards to recent findings. Furthermore, experiences with the experiment in school and university lab‐trainings as well as in teacher trainings are reported. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
28. Reproduzierbarkeit in der elektroorganischen Synthese – Mythen und Missverständnisse.
- Author
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Beil, Sebastian B., Pollok, Dennis, and Waldvogel, Siegfried R.
- Subjects
- *
RENAISSANCE - Abstract
Die Verwendung von elektrischem Strom als spurenlosem Aktivator und Reagenz erlebt eine Renaissance in der organischen Synthesechemie. Diese nachhaltige Synthesemethode entwickelt sich zu einem hochaktuellen Thema in der modernen organischen Chemie. Forscher aus verschiedenen wissenschaftlichen Bereichen steigen in dieses interdisziplinäre Feld ein, was zu unterschiedlichen Parametern und Methoden der Experimentbeschreibungen führt. Die Variation in den berichteten Parametern kann zu Problemen bei der Reproduzierbarkeit elektroorganischer Synthesen führen. So sind z. B. Parameter wie die Stromdichte oder der Elektrodenabstand in manchen Fällen bedeutender als oft vermutet. Dieser Kurzaufsatz bietet Richtlinien für die Beschreibung elektrosynthetischer Daten an und räumt mit Mythen über diese Technik auf, wodurch die experimentellen Parameter vereinheitlicht werden sollen, um die Reproduzierbarkeit zu erleichtern. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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29. Silylierte Schwefelsäure: Herstellung eines Tris(trimethylsilyl)oxosulfonium[(Me3Si‐O)3SO]+‐Salzes.
- Author
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Bläsing, Kevin, Labbow, Rene, Schulz, Axel, and Villinger, Alexander
- Subjects
- *
ANIONS , *IONS - Abstract
Die Chemie der silylierten Schwefelsäure, O2S(OSiMe3)2 (T2SO4, T=Me3Si; auch bekannt als Bis(trimethylsilyl)sulfat), wurde im Detail untersucht, mit dem Ziel, die formalen Autosilylierungsprodukte der silylierten Schwefelsäure, [T3SO4]+ und [TSO4]−, in Analogie zu den bekannten protonierten Spezies, [H3SO4]+ und [HSO4]−, zu synthetisieren. Die Synthese des [TSO4]−‐Ions gelingt nur, wenn eine Base, wie z. B. OPMe3, die bei der Silylierung ein schwach koordinierendes Kation bildet, mit T2SO4 umgesetzt wird, was zur Bildung von [Me3POT]+[TSO4]− führt. Die [T3SO4]+‐Salze können ausgehend von T2SO4 in der Reaktion mit [T‐H‐T]+[B(C6F5)4]− oder T+[CHB11Br6H5]− isoliert werden, aber nur, wenn ein schwach koordinierendes Anion als Gegenion verwendet wird. Alle silylierten Verbindungen konnten kristallisiert und strukturell charakterisiert werden. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
30. Synthesis and Characterization of a Novel Class of Zwitterionic Fluorocarbon Surfactants Based on Perfluorobutyl.
- Author
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Xuhong Jia, Rui Huang, Xiaoguang Yang, Wan Tao, and Xinhua Zhu
- Abstract
Perfluorooctane sulfonate (PFOS) and its derivatives had been banned due to their potential environmental hazards, although they possessed excellent surface activity. An effective method to solve this problem was to shorten the fluorocarbon chain of these surfactants from C8H17 to C4F9. As previous studies had shown, zwitterionic surfactants possess higher surface activity but have lower toxicity compared to other types of surfactants. In view of this, a class of novel zwitterionic fluorocarbon surfactants (n-CFNA-Br) with perfluorobutyl moiety was synthesized in this work. Their structures were characterized by FTIR, ¹H NMR, 13C NMR, 19F NMR and MS. The results showed that all synthesized n-CFNA-Br had almost the same minimum surface tension, but their critical micelle concentration (CMC) decreased with increasing length of hydrophobic carbon chain. In pure water, the surface tension at the CMC (γCMC) of the four n-CFNA-Br were about 20 mN/m, and the CMC values were 7.73 mmol/L for 1-CFNA-Br, 4.70 mmol/L for 2-CFNA-Br, 4.13 mmol/L for 3-CFNA-Br, and 3.36 mmol/L for 4-CFNA-Br, indicating high efficiency and effectiveness. In 0.1 mol/L NaCl, the CMC values reduced to less than half of the CMC values measured in the pure aqueous surfactant solution, while the surface tensions γCMC remained almost unchanged, indicating good salinity tolerance of the synthesized surfactants. The acidic surfactant solutions exhibited similar CMC values to the saline solutions, but the surface tension γCMC increased slightly to 25 mN/m. However, further investigation showed that the n-CFNA-Br surfactants exhibited poor surface activity in alkaline solution (0.1 mol/L NaOH). In the pH range of 6.6 to 10.4, white precipitates appeared in the surfactant solutions after some time, indicating that the n-CFNA-Br are not suitable for use in alkaline systems with pH greater than 6.6. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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31. A critical review of analytical and numerical models of condensation in microchannels.
- Author
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Keniar, Khoudor, El Fil, Bachir, and Garimella, Srinivas
- Subjects
- *
MICROCHANNEL flow , *CONDENSATION , *REDUCED-order models , *REYNOLDS number , *ANNULAR flow , *CONDENSERS (Vapors & gases) - Abstract
Understanding condensation in microchannels is critical for designing optimized and compact microchannel condensers, which have the potential to increase system level efficiency and reduce system size. Analytical and numerical models can yield insights into local condensation phenomena. This study provides a review of models of condensation in microchannels. These models are categorized based on the applicable, typically annular and intermittent, flow regimes. Annular-flow-based models are further subdivided into analytical models with closed-form solutions, analytical models with numerical solutions, reduced-order CFD models, and full-fledged CFD models. Intermittent-flow-based models are subdivided into single-bubble, repeated-unit-cell, and overall-bubble-train models. The characteristics, use, and range of applicability of each of these models is highlighted. A criterion for the film Reynolds number is proposed for internal forced convective condensation in microchannels, to assess the validity of the modeling assumptions. Annular flow models using the laminar film assumption appear to be valid for Re δ0 < ~ 360, beyond which turbulent effects must be modeled. Intermittent flow models using the laminar film assumption, in turn, appear to be valid for Re δ0 < ~ 130. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
32. Le raisonnement clinique : regards rétrospectif et prospectif sur le concept.
- Author
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Deschênes, Marie-France
- Abstract
Background: There has been extensive publication on the concept of clinical reasoning in health science education in recent decades. However, the diversity of literature and theories on the concept can be confusing. Aim: To present a brief synthesis of theoretical foundations related to clinical reasoning in health science education. Results: While cognitivists approach clinical reasoning through the lens of the practitioner's cognitive and metacognitive processes, social-cognitivists study "naturalistic decision-making" where recognition of contextual signs and signals guides clinical reasoning. Conceptualized as a "social construct", clinical reasoning is also a phenomenon leading to professional socialization where the morals, values and common practices in a profession are conveyed. Finally, artifacts such as artificial intelligence and the tools or materials of practice increase the practitioner's cognition. An ecological cognition, embedded in a complex environment, is proposed. Discussion and conclusions: The main theoretical foundations related to clinical reasoning suggest pedagogical support for competency development in addition to the use of a variety of assessment tools. The contribution of other theories from neuroscience, sociology and complexity sciences could enrich the understanding of the concept and ensure progress in the teaching and learning of the competency and in research in the field. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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33. Prise en charge du trouble panique chez le sujet âgé.
- Author
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Pace, Maxime, Heckendorn, Mathilde, Aouizerate, Bruno, Hanon, Cécile, Seigneurie, Anne-Sophie, Lavaud, Pierre, Hozer, Franz, Pascal De Raykeer, Rachel, Guerin-Langlois, Christophe, Cormier, Lucile, Poncelin De Raucourt, Hélène, Limosin, Frédéric, and Hoertel, Nicolas
- Abstract
Résumé: Le trouble panique chez le sujet âgé est sous-étudié bien qu'il soit associé à un impact fonctionnel négatif majeur, à une altération de la qualité de vie et à une augmentation significative du risque suicidaire. Ce trouble peut être sous-diagnostiqué et parfois le traitement n'est pas adapté du fait d'une absence de consensus national et international concernant cette population vulnérable. Peu d'essais thérapeutiques ont été spécifiquement consacrés à l'efficacité et la tolérance des traitements psychothérapiques et pharmacologiques du trouble panique chez le sujet âgé. Par ailleurs, les approches actuelles de dépistage et de prise en charge se fondent principalement sur des avis d'experts ou sur l'extrapolation de données issues de patients plus jeunes souffrant de cette pathologie. L'objectif de cet article est de proposer une synthèse des connaissances actuelles concernant les traitements psychothérapiques et pharmacologiques du trouble panique chez les sujets âgés et de proposer un algorithme médical de traitement afin de guider et standardiser les décisions prises dans le traitement du trouble panique chez les adultes vieillissants. Panic disorder in the elderly is an understudied disorder, despite being associated with substantial functional impairment, diminished quality of life and increased suicide risk in this population. This disorder is likely to be underdiagnosed and sometimes inadequately treated in the absence of national and international guidelines for this vulnerable population. Few therapeutic trials have specifically focused on the efficacy and tolerability of pharmacologic and psychotherapy treatments for panic disorder in the elderly, and current approaches to detect and manage this disorder are mainly based on experts' opinion or extrapolation from data available in younger adults. This report aims to provide a summary of current knowledge on pharmacologic and psychotherapeutic treatments for panic disorder in the elderly, and to propose a medical treatment algorithm, which should be viewed as a tool that may contribute to the choice of treatment, especially for treatment-resistant older patients with panic disorder. The main results here are the emphasis on antidepressant treatment, like selective serotonin reuptake inhibitor (SSRI), restricted benzodiazepine usage, take care of drug interactions, and importance of psychotherapy like cognitive behavioral therapy (CBT). [ABSTRACT FROM AUTHOR]
- Published
- 2020
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34. Unterrichtsqualität in den Fachdidaktiken im deutschsprachigen Raum – zwischen Generik und Fachspezifik.
- Author
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Praetorius, Anna-Katharina, Herrmann, Christian, Gerlach, Erin, Zülsdorf-Kersting, Meik, Heinitz, Benjamin, and Nehring, Andreas
- Subjects
HISTORY of education ,SCIENCE education ,EFFECTIVE teaching ,PHYSICAL education - Abstract
Copyright of Unterrichtswissenschaft (Springer Science & Business Media B.V.) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
- Full Text
- View/download PDF
35. Blinde Flecken des Modells der drei Basisdimensionen von Unterrichtsqualität? Das Modell im Spiegel einer internationalen Synthese von Merkmalen der Unterrichtsqualität.
- Author
-
Praetorius, Anna-Katharina, Rogh, Wida, and Kleickmann, Thilo
- Subjects
EFFECTIVE teaching - Abstract
Copyright of Unterrichtswissenschaft (Springer Science & Business Media B.V.) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
- Full Text
- View/download PDF
36. Bildung Stabiler All‐Silicium Varianten von 1,3‐Cyclobutandiyl im Gleichgewicht.
- Author
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Yildiz, Cem B., Leszczyńska, Kinga I., González‐Gallardo, Sandra, Zimmer, Michael, Azizoglu, Akin, Biskup, Till, Kay, Christopher W. M., Huch, Volker, Rzepa, Henry S., and Scheschkewitz, David
- Abstract
Hauptgruppenanaloga von 1,3‐Cyclobutandiylen faszinieren mit ihrer einzigartigen Reaktivität und ihren elektronischen Eigenschaften. Bisher sind allerdings nur heteronukleare Vertreter isoliert worden. Wir berichten hier über die Isolierung und Charakterisierung von All‐Silicium‐1,3‐Cyclobutandiylen als stabile Singulettspezies mit geschlossenschaliger Konfiguration aus den reversiblen Reaktionen von Cyclotrisilen c‐Si3Tip4 (Tip=2,4,6‐Triisopropylphenyl) mit den N‐heterocyclischen Silylenen c‐[(CR2CH2)(NtBu)2]Si: (R=H oder Methyl) mit gesättigten Grundgerüsten. Bei erhöhten Temperaturen werden aus diesen Gleichgewichtsmischungen Tetrasilacyclobutene erhalten. Die analoge Reaktion mit dem ungesättigten N‐heterocyclischen Silylen c‐(CH)2(NtBu)2Si: verläuft direkt zum entsprechenden Tetrasilacyclobuten ohne Nachweis des angenommenen 1,3‐Cyclobutandiyl‐Zwischenprodukts. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
37. Die "grüne" elektrochemische Synthese von Periodat.
- Author
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Arndt, Sebastian, Weis, Dominik, Donsbach, Kai, and Waldvogel, Siegfried R.
- Subjects
- *
OXIDATION - Abstract
Hochreines Periodat ist relativ teuer, wird jedoch für viele anspruchsvolle Anwendungen, wie zur Synthese von Pharmawirkstoffen (API) benötigt. Die hohen Kosten entstehen durch die Verwendung von Bleidioxid‐Anoden und durch den Einsatz von teuren Edukten in den zurzeit verfügbaren elektrochemischen Herstellungsmethoden. Eine direkte und kosteneffiziente elektrochemische Synthese von Periodat aus Iodid als kostengünstiges und leicht verfügbares Edukt wird berichtet. Die Oxidation wird an bordotierten Diamantanoden durchgeführt, die beständig, metallfrei und ungiftig sind. Die Vermeidung von Bleidioxid reduziert letztendlich die Kosten für die Aufreinigung sowie die Qualitätssicherung. Der elektrolytische Prozess wurde in statistischen Versuchsreihen optimiert und in einer elektrochemischen Flusszelle skaliert. Die Raumzeitausbeute konnte durch mehrfaches Durchpumpen erhöht werden. Eine LC‐PDA‐Analysemethode wurde etabliert, die eine einfache und simultane Quantifizierung von Iodid, Iodat und Periodat in hoher Präzision erlaubt. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
38. Chemical Synthesis and Immunological Evaluation of a Pentasaccharide Bearing Multiple Rare Sugars as a Potential Anti‐pertussis Vaccine.
- Author
-
Wang, Peng, Huo, Chang‐xin, Lang, Shuyao, Caution, Kyle, Nick, Setare Tahmasebi, Dubey, Purnima, Deora, Rajendar, and Huang, Xuefei
- Subjects
- *
CHEMICAL synthesis , *BORDETELLA pertussis , *VACCINES , *ENZYME-linked immunosorbent assay , *SUGARS - Abstract
With the infection rate of Bordetella pertussis at a 60‐year high, there is an urgent need for new anti‐pertussis vaccines. The lipopolysaccharide (LPS) of B. pertussis is an attractive antigen for vaccine development. With the presence of multiple rare sugars and unusual glycosyl linkages, the B. pertussis LPS is a highly challenging synthetic target. In this work, aided by molecular dynamics simulation and modeling, a pertussis‐LPS‐like pentasaccharide was chemically synthesized for the first time. The pentasaccharide was conjugated with a powerful carrier, bacteriophage Qβ, as a vaccine candidate. Immunization of mice with the conjugate induced robust anti‐glycan IgG responses with IgG titers reaching several million enzyme‐linked immunosorbent assay (ELISA) units. The antibodies generated were long lasting and boostable and could recognize multiple clinical strains of B. pertussis, highlighting the potential of Qβ‐glycan as a new anti‐pertussis vaccine. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
39. Green synthesis of Ag, Zn and Cu nanoparticles from aqueous extract of Spondias mombin leaves and evaluation of their antibacterial activity.
- Author
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Adeyemi, D. K., Adeluola, A. O., Akinbile, M. J., Johnson, O. O., and Ayoola, G. A.
- Subjects
- *
ANTIBACTERIAL agents , *ANTI-infective agents , *METAL nanoparticles , *SCANNING electron microscopes , *NANOMEDICINE , *NANOPARTICLES , *PLANT extracts , *ABSORPTION spectra - Abstract
Background: Nanotechnology offers an advantage as a green route for synthesis of metal nanoparticles (NPs) with plant extracts as capping agent. Spondias mombin is a fruit-bearing tree and its leaf extracts have been reported to possess anxiolytic, hypoglycaemic, antiepileptic, antipsychotic, sedative, antioxidant, and antimicrobial properties. The objective of the study is to determine the antibacterial potential of a simple non-toxic product of green synthesis of metallic (Ag, Zn and Cu) nanoparticles using the leaf of Spondias mombin aqueous extracts (SMAE) as a reducing and capping agents of the metal ions. Methodology: Nanoparticles were characterized by UV visible spectrophotometeric analysis, Fourier Transform Infra-Red (FT-IR) spectrophotometer and scanning electron microscope (SEM). Antimicrobial activities of synthesized NPs against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were determined by agar well diffusion technique. Results: The synthesized NPs varied in colour from dark brown to green and appears dominantly spherical, occasionally rod or triangular shaped with size ranging from 65-90 nm. UV spectroscopy absorption spectra of Ag, Zn and Cu NPs had absorbance peak at 267, 262 and 765 nm respectively. FT-IR spectrometry of Zn NP, Cu NP, and SMAE gave wave number ranging from 895.71-3320.67, 747.02-3225.45 and 658.25-3674.49 respectively. FT-IR analysis showed that SMAE acted as reducing and stabilizing agent while the NPs exhibited lower energy absorption band when compared to the plant extract. The NPs demonstrated higher antimicrobial activities against S. aureus than Ps. aeruginosa and E. coli. The antimicrobial activity was higher with copper NP than Ag and Zn NPs, and also higher than SMAE. Conclusion: The result from this study presents an indication for an alternative means for development of novel antimicrobial agents for clinical and biotechnological applications. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
40. Ottokraftstoffe aus erneuerbarem Methanol.
- Author
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Jung, Constanze, Seifert, Peter, Mehlhose, Friedemann, Hahn, Christoph, Schröder, Daniel, Wolfersdorf, Christian, Kureti, Sven, and Meyer, Bernd
- Subjects
- *
FUEL quality , *METHANOL as fuel , *METHANOL , *CHEMICAL properties , *PROCESS optimization , *GASOLINE - Abstract
For synthesis of emission‐reduced gasoline fuels from regenerative methanol, catalyst and process optimization was carried out as part of the joint research project Kopernikus „Power‐to‐X". For this purpose, a laboratory test plant had to be designed and commissioned, and process parameters for an optimized fuel quality had to be worked out considering variations of catalyst and feed. The precisely adjustable isothermal synthesis conditions allow the specific adjustment of the chemical properties of the high‐octane petrol produced. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
41. Flow boiling of carbon dioxide: Heat transfer for smooth and enhanced geometries and effect of oil. state of the art review.
- Author
-
Mastrullo, R., Mauro, A.W., and Viscito, L.
- Subjects
- *
HEAT transfer , *HEAT transfer coefficient , *CARBON dioxide , *STATISTICAL smoothing , *LUBRICATION & lubricants , *PETROLEUM - Abstract
• Collection of boiling data for pure CO 2 and with CO 2 /lubricant mixtures. • Effect of operating conditions and oil presence on the heat transfer analyzed. • Data in smooth tubes sorted and analyzed according to their flow pattern. • Experimental data compared to only-convective and only-nucleative heat transfer. • Flow boiling HTCs in smooth tubes accurately predicted by fang et al. correlation. This paper presents a state-of-the-art review on flow boiling of carbon dioxide, including experimental studies and correlations for smooth and enhanced tubes, with pure CO 2 and CO 2 /lubricant mixtures. Specifically, 5223 CO 2 heat transfer coefficient data in smooth tubes are collected, and the effect of the operating conditions is discussed. Additional 883 data points in microfin tubes and 1184 experimental heat transfer coefficients in smooth tubes with CO 2 /oil mixture are also collected, and the influence of the microfin structure and of the oil presence on the heat transfer mechanism is analyzed. The statistical analysis has highlighted that the CO 2 -based correlation of Fang et al. is very accurate (MAE = 5.1%) for the smooth tube database, whereas the heat transfer coefficients in microfin tubes are satisfactorily predicted (MAE = 30.5%) with the model of Mehendale. Among the available correlations for CO 2 /oil mixture in smooth tubes, the method of Gao et al. provides the highest accuracy (MAE = 63.2%). [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
42. Aerogele – Moderne Funktionswerkstoffe für den Chemieunterricht?
- Author
-
Fenner, Christiane, Gräb, Patrick, Reichenauer, Gudrun, Scherdel, Christian, Beierle, Kristina, and Geidel, Ekkehard
- Subjects
- *
SILICA gel , *AEROGELS , *SILICA , *CLASSROOMS , *MATERIALS - Abstract
Due to their specific highly porous structure, aerogels as modern functional materials distinguish themselves by several outstanding, systematically adjustable properties. The resulting diversity of potential applications makes this class of materials the subject of intense research. The article adapts the synthesis and drying route of an organically modified silica aerogel to a school setting. The characterizations confirm that the resulting material shows attributes of a typical aerogel. Finally, examples of classroom implementation with simple hands‐on experiments and possible didactic contexts are presented. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
43. Efficacité des Complexes Organo/Inorgano Argileux pour l'élimination des métaux lourds à partir des solutions aqueuses.
- Author
-
Cherifi-Naci, H. and Louhab, K.
- Subjects
SEWAGE ,HEAVY metals ,INDUSTRIAL wastes ,WASTEWATER treatment ,BENTONITE - Abstract
Copyright of Algerian Journal of Environmental Science & Technology is the property of Algerian Journal of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
44. Soil bacterial biodiversity characterization by flow cytometry
- Author
-
Verónica A. El Mujtar, Fernando Chirdo, Antonio Lagares, Luis Wall, and Pablo Tittonell
- Subjects
soil bacterial biodiversity ,Bacteria ,Cytométrie en flux (cellules) ,Ecological Modeling ,flow cytometry ,Analyse qualitative ,P34 - Biologie du sol ,Échantillonnage de sol ,information ,high-throughput analysis ,synthèse ,soil bacterial extraction ,Analyse de sol ,Technique analytique ,Ecology, Evolution, Behavior and Systematics ,soil bacterial recovery efficiency - Abstract
The importance of soil biodiversity is increasingly recognized in agriculture and natural resource research and development. Yet, traditional soil biodiversity assessments are costly and time-consuming, limiting the extent and frequency of sampling and analysis in space and time. Flow cytometry (FCM) is a powerful technique to characterize cell communities due to its high robustness and accuracy, requiring only a short time for the characterization. Therefore, FCM could expand soil research capabilities by allowing the characterization of different aspects of bacterial biodiversity. However, this implementation of FCM requires the previous dispersion, separation and purification of bacteria from complex soil matrices. Moreover, soil monitoring programs or evaluation of soil management practices require high-throughput analysis. In this context, soil processing protocols need to consider not only an adequate recovery of undamaged, representative and pure soil bacteria, but also short-time processing requirements. Although soil processing protocols have been reported over time, to our knowledge, there is no recommended soil extraction protocol for high-throughput analysis of bacterial biodiversity by FCM. We reviewed the state-of-art of the use of flow cytometry in scientific research and the protocols used for the extraction of bacteria from soil. We analysed the literature to take stock of the diversity of methodologies for soil processing and applications of flow cytometry in bacterial characterization considering abundance, diversity, community structure and functional properties. This review provides several lines of evidence of the use of flow cytometry for soil bacterial biodiversity (SBB) characterization, highlighting its potential for soil monitoring and studies on soil bacterial community dynamics. The review also highlights and discusses the most relevant constraints and research gaps that need to be considered for high-throughput analysis of SBB by FCM, such as evaluation of scale-down, new reagents for and methods of purification, threshold of bacterial recovery efficiency and selection of a standardized and validated protocol. We proposed a protocol for soil bacterial extraction for high-throughput analysis of SBB by FCM and we provided detailed databases of systematized information that would be useful to the scientific community.
- Published
- 2022
45. Blending et analogie : enjeux épistémologiques
- Author
-
Albano, Mariangela and Monneret, Philippe
- Subjects
blending ,compositionnalité ,synthèse ,cognitive functions ,synthesis ,compositionality ,fonctions cognitives ,analogie ,similarité ,analogy ,similarity - Abstract
Cet article a pour objet de mettre en perspective, selon une approche épistémologique, les théories du blending (ou « intégration conceptuelle ») et de l’analogie. Il se situe dans le cadre de la sémantique cognitive (Fauconnier, 1985 ; Fauconnier et Turner, 1996, 1998 et 2002), de la linguistique analogique (Monneret 2004, 2014, 2017, 2018, 2019, 2021, 2023) et de la psychologie cognitive (Gentner 1983 ; Gentner et al., 2001 ; Hofstadter 2001 ; Hofstadter et Fluid Analogies Research Group 1995; Hofstadter et Sander 2013). Plus spécifiquement, la question posée est celle de savoir si le processus analogique est sous-jacent à la formation et à la structuration de l’IC ou si ce dernier n’est qu’un cas particulier de processus analogique. L’article se développera en trois points i) une introduction aux espaces mentaux et à l’IC visant à examiner la place de l’analogie dans le modèle ; ii) une présentation du modèle analogique en linguistique ; iii) une comparaison entre les deux modèles. This paper aims to put into perspective, through an epistemological approach the theories of blending (or “conceptual integration”, CI) and analogy. It is based on the integration of cognitive semantics approach (Fauconnier, 1985; Fauconnier and Turner, 1996, 1998 and 2002), analogical linguistics approach (Monneret 2004, 2014, 2017, 2018, 2019, 2021, 2023) and cognitive psychology approach (Gentner 1983; Gentner et al., 2001; Hofstadter, 2001; Hofstadter and Fluid Analogies Research Group 1995; Hofstadter and Sander, 2013). More specifically, the question posed is whether the analogical process underlies the formation and structuring of CI or whether CI is just a special case of analogical process. The paper will develop in three points i) an introduction to mental spaces and CI aimed at examining the place of analogy in the model; ii) a presentation of the analogical model in linguistics; iii) a comparison between the two models.
- Published
- 2023
46. Isolation of metalated ylides and their application in the synthesis of strong donor ligands for homogeneous catalysis and the stabilization of reactive main group compounds
- Author
-
Darmandeh, Heidar
- Subjects
540 Chemie, Kristallographie, Mineralogie ,ddc:540 ,Phosphane ,Ylide ,Ligand ,Synthese ,Homogene Katalyse - Abstract
Metallierte Ylide eignen sich als \(\sigma/\pi\)-Donorliganden zur Stabilisierung von niedervalenten Verbindungen. Vertreter dieser Ligandenklasse basierten jedoch auf PPh\(_3\)-Gruppen, die auf Grund sp\(^{2}\)-hybridisierter Bindungen zu Zersetzung neigten. Das Ziel der Arbeit war die Synthese von Metallierten Yliden (\(^{Cy}\bf {Y-M}\)), die auf einer PCy\(_3\) Einheit basieren. Durch sp\(^{3}\)-hybridiserte Bindungen, sollten resultierende Produkte stabiler sein. Nach erfolgreicher Isolierung wurden \(^{Cy}\)Y als stabilisierende Liganden in der Synthese von niedervalenten Verbindungen eingesetzt. Dies ermöglichte die Isolierung von stabilen Tetrylenen, deren Eigenschaften und Reaktivität im Detail erforscht wurde. Im zweiten Teil der Arbeit wurden \(^{Cy}\)Y-Phosphane synthetisiert, deren elektronischen und sterischen Eigenschaften bestimmt und ihre Eignung zur Synthese von Au(I)-Komplexen untersucht. \(^{Cy}\)YPhos-Au(I)-Komplexe wurden erfolgreich in der homogenen Katalyse eingesetzt und ihre Aktivität konnte durch seltene Au\(\cdot\)H WW erklärt werden.
- Published
- 2023
47. Synthese und Reaktivität eines cyclischen (Alkyl)(amino)carbens mit 1,1'-Ferrocenylen-Rückgrat
- Author
-
Volk, Julia
- Subjects
Aktivierung kleiner Moleküle ,Chemie ,Carben ,Naturwissenschaften ,Synthese ,Carbene ,Ferrocen ,subvalente Verbindungen - Abstract
Dem Fonds der Chemischen Industrie (FCI) danke ich für ein Kekulé-Promotionsstipendium und die damit verbundene finanzielle Ermöglichung dieses Projekts.
- Published
- 2023
- Full Text
- View/download PDF
48. Growth of graphene/hexagonal boron nitride heterostructures using molecular beam epitaxy
- Author
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Nakhaie, Siamak, Riechert, Henning, Masselink, Ted W., and Sergei, Novikov
- Subjects
MBE ,synthesis ,Bornitrid ,graphene ,Synthese ,530 Physik ,Graphen ,500 Naturwissenschaften und Mathematik ,UP 7550 ,heterostructures ,molecular beam epitaxy ,Heterostrukturen ,Molekularstrahlepitaxie ,ddc:530 ,ddc:500 ,h-BN ,hexagonal boron nitride - Abstract
Zweidimensionale (2D) Materialien bieten eine Vielzahl von neuartigen Eigenschaften und sind aussichtsreich Kandidaten für ein breites Spektrum an Anwendungen. Da hexagonales Bornitrid (h-BN) für eine Integration in Heterostrukturen mit anderen 2D Materialien geeignet ist, erweckte dieses in letzter Zeit großes Interesse. Insbesondere van-der-Waals-Heterostrukturen, welche h-BN und Graphen verbinden, weisen viele potenzielle Vorteile auf, verbleiben in ihrer großflächigen Herstellung von kontinuierlichen Filmen allerdings problematisch. Diese Dissertation stellt eine Untersuchung betreffend des Wachstums von h-BN und vertikalen Heterostrukturen von Graphen und h-BN auf Ni-Substraten durch Molekularstrahlepitaxie (MBE) vor. Zuerst wurde das Wachstum von h-BN mittels elementarer B- und N-Quellen auf Ni als Wachstumssubstrat untersucht. Kristalline h-BN-Schichten konnten durch Raman-spektroskopie nachgewiesen werden. Wachstumsparameter für kontinuierliche und atomar dünne Schichten wurden erlangt. Das Keimbildungs- und Wachstumsverhalten so wie die strukturelle Güte von h-BN wurden mittels einer systemischen Veränderung der Wachstumstemperatur und -dauer untersucht. Die entsprechenden Beobachtungen wie der Änderungen der bevorzugten Keimbildungszentren, der Kristallgröße und der Bedeckung des h-BN wurden diskutiert. Ein Wachstum von großflächigen vertikalen h-BN/Graphen Heterostrukturen (h-BN auf Graphen) konnte mittels einem neuartigen, MBE-basierenden Verfahren demonstriert werden, welche es h-BN und Graphen jeweils erlaubt sich in der vorteilhaften Wachstumsumgebung, welche von Ni bereitgestellt wird, zu formen. In diesem Verfahren formt sich Graphen an der Schnittstelle von h-BN und Ni durch Präzipitation von zuvor in der Ni-Schicht eingebrachten C-Atomen. Schließlich konnte noch ein großflächiges Wachstum von Graphen/h-BN-Heterostrukturen (Graphen auf h-BN) durch das direkte abscheiden von C auf MBE-gewachsenen h-BN gezeigt werden. Two-dimensional (2D) materials offer a variety of novel properties and have shown great promise to be used in a wide range of applications. Recently, hexagonal boron nitride (h-BN) has attracted significant attention due to its suitability for integration into heterostructures with other 2D materials. In particular, van der Waals heterostructures combining h-BN and graphene offer many potential advantages, but remain difficult to produce as continuous films over large areas. This thesis presents an investigation regarding the growth of h-BN and vertical heterostructures of graphene and h-BN on Ni substrates using molecular beam epitaxy (MBE). The growth of h-BN from elemental sources of B and N was investigated initially by using Ni as the growth substrate. The presence of crystalline h-BN was confirmed using Raman spectroscopy. Growth parameters resulting in continuous and atomically thin h-BN films were obtained. By systematically varying the growth temperature and time the structural quality as well as the nucleation and growth behavior of h-BN was studied. Corresponding observations such as changes in preferred nucleation site, crystallite size, and coverage of h-BN were discussed. Growth of h-BN/graphene vertical heterostructures (h-BN on graphene) over large areas was demonstrated by employing a novel MBE-based technique, which allows both h-BN and graphene to form in the favorable growth environment provided by Ni. In this technique, graphene forms at the interface of h-BN/Ni via the precipitation of C atoms previously dissolved in the thin Ni film. No evidence for the formation of BCN alloy could be found. Additionally, the suitability of ultraviolet Raman spectroscopy for characterization of h-BN/graphene heterostructures was demonstrated. Finally, growth of large-area graphene/h-BN heterostructures (graphene on h-BN) was demonstrated via the direct deposition of C on top of MBE-grown h-BN.
- Published
- 2023
- Full Text
- View/download PDF
49. New and promising precursors for chemical vapor phase processing of coinage metals, iridium and yttrium oxide thin films
- Author
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Boysen, Nils
- Subjects
Dünne Schicht ,Präkursor ,CVD-Verfahren ,540 Chemie, Kristallographie, Mineralogie ,ddc:540 ,Synthese ,Atomlagenabscheidung - Abstract
Präkursoren mit Relevanz für die Gasphasenabscheidung von verschiedenen Materialsystemen mittels der chemischen Gasphasenabscheidung (CVD) oder Atomlagenabscheidung (ALD) müssen spezifisch für solche Prozesse entwickelt werden. In dieser Arbeit wurden neuartige Präkursoren für die Abscheidung von Münzmetallen, Iridium und Yttrium(III)-Oxid Schichten hergestellt. Im ersten Kapitel wird die Präkursorchemie für die Abscheidung von Kupferdünnschichten diskutiert, wobei das zweite Kapitel sich mit der Präkursorchemie und der Abscheidung von Yttrium(III)-Oxid Schichten beschäftigt. Im letzten Kapitel wird die Präkursorchemie und Abscheidung von metallischen Iridium Dünnschichten mittels der CVD beleuchtet. Die Entwicklung neuartiger Präkursoren in dieser Arbeit kann als eine einer der zentralen Säulen betrachtet werden, um Abscheidungsprozesse zu verbessern und schließlich eine Anwendung der Materialien in mikro- und optoelektronischen Geräten zu ermöglichen., Precursors relevant for the vapor phase processing of different material systems by chemical vapor deposition (CVD) or atomic layer deposition (ALD) need to be rationally developed to fulfill the special demands of such processes. In this thesis, new and promising precursors for the deposition of coinage metals, metallic iridium, and yttrium(III)-oxide thin films were realized and evaluated. In a first chapter, the precursor chemistry and deposition of metallic copper thin films by spatial ALD is highlighted, while the second chapter focusses on the precursor chemistry and thermal ALD of yttrium(III)-oxide thin films. The last chapter deals with the development of new precursors for the CVD of metallic iridium thin films by metal-organic CVD. Developing advanced precursor chemistries as highlighted in this thesis significantly enhances the deposition process characteristics and thus applicability of the thin films in micro- and optoelectronic devices.
- Published
- 2023
50. Porous materials for water and air purification: from synthetic ordered mesoporous silica COK-12 to natural fungi
- Author
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Henning, Laura Marie
- Subjects
600 Technik, Medizin, angewandte Wissenschaften::620 Ingenieurwissenschaften::620 Ingenieurwissenschaften und zugeordnete Tätigkeiten ,geordnetes mesoporöses Siliziumdioxid ,modification ,synthesis ,purification ,Modifizierung ,600 Technik, Medizin, angewandte Wissenschaften::660 Chemische Verfahrenstechnik::666 Keramiktechnologie und zugeordnete Technologien ,Pilzmaterialien ,Synthese ,fungal materials ,ordered mesoporous silica ,Aufreinigung - Abstract
Clean water and air are major cornerstones of a healthy life and environment. However, an increase in population and living standards strains our resources and causes high pollution levels. At the same time, tightened emission laws necessitate advancements in the fields of water and air purification. Promising approaches for the treatment of wastewater and polluted air include adsorption and filtration. While currently mostly inexpensive petroleum-based polymeric compounds are processed into adsorbents, filters, and membranes, they are at best scarcely regenerable and recyclable. This dissertation pursues two particularly promising approaches regarding the establishment of more sustainable materials in the fields of water and air purification. Firstly, the utilization of ceramic materials, coming with higher initial costs but offering longer lifetimes and higher resistances, is explored. To this regard, the ordered mesoporous silica material COK-12 offers tremendous possibilities in tailoring its structural and chemical properties, leading to highly optimized purification results. Secondly, the targeted cultivation of natural fungi represents a simple, sustainable, and economic option for pollutant removal. The incorporation of varying amounts of the swelling agent p-xylene and the combination with a thermal aging step during the synthesis of COK-12 is studied to tailor the resulting mesostructure. A mesocellular foam with ink-bottle shaped pores and significantly enhanced cell and window sizes is obtained using low amounts of swelling agent, paving the way for enhanced mass transfer and the immobilization of larger compounds, e.g., for adsorptive applications. Graphene oxide (GO) is grafted onto thermally aged large-pore COK-12 powder to enhance the adsorption of the cationic dye methylene blue from aqueous solutions. Due to the GO’s abundant oxygenated functional surface groups, facilitating the formation of strong negative surface charges, the composite material displays a remarkably high adsorption capacity surpassing that of COK-12 and similar composite adsorbents, even under simulated dye effluent conditions. To circumvent nanopowder handling and obtain hierarchically micro-/ meso-/ macroporous and mechanically robust silica monoliths for filtration applications, the influence of additive-free spark plasma sintering (SPS) as well as conventional sintering on COK-12 is investigated. Within the studied parameter range, the overall mesostructure prevails for both SPS and conventional sintering. The simultaneous application of pressure and temperature during SPS results in a more distinct decrease in porosity and deviations from the theoretical lattice, but a higher preservation of the mesopore size and lattice parameter compared to the conventional sintering method. Furthermore, the higher mechanical values at comparable porosities allow to successfully use the SPS processed monoliths for the filtration of an oil-in-water emulsion in a dead-end water filtration setup. Although a higher macroporosity is desirable to decrease the pressure drop, estimations on the true gas permeability of the COK-12 monoliths place them in suitable permeability range for aerosol filtration applications. The suitability of the fungus Fomes fomentarius as a biosorbent and the effect of its growth conditions on the adsorption performance for dyes from aqueous solutions is studied as an alternative pathway to highly engineered synthetic materials. Lab-cultivated mycelia, grown on hemp shives or in liquid medium, exhibit a superior adsorption performance over the naturally grown fruiting body. Accordingly, the fungal cultivation conditions allow to tune the fungal properties and adsorption performance. Thereby, the utilization of cheap agricultural waste materials as growth substrates is particularly promising. Overall, both synthetic and highly engineered COK-12 as well as natural and renewable F. fomentarius represent sustainable alternatives to petroleum-based polymeric materials in the field of water and air purification, suitable for demanding and long-term or simple and economically friendly applications., Sauberes Wasser und saubere Luft sind fundamental für ein gesundes Leben in einer lebenswerten Umwelt. Eine wachsende Erdbevölkerung mit steigenden Lebensstandards beansprucht jedoch zunehmend Ressourcen und belastet die Umwelt mit Schadstoffen. Gleichzeitig erfordern verschärfte Emissionsgesetze die Weiterentwicklung von Technologien und Materialien im Bereich der Wasser- und Luftreinigung. Zur Reinigung kontaminierten Wassers und verschmutzter Luft sind Adsorption und Filtration vielversprechende Ansätze. Für Adsorbentien, Filter und Membranen kommen derzeit überwiegend preisgünstige, erdölbasierte Polymerwerkstoffe zur Anwendung, trotz ihrer geringen Recyclier- und Regenerierbarkeit. Diese Dissertation beleuchtet zwei besonders erfolgversprechende Ansätze, nachhaltigere Materialien im Bereich der Wasser- und Luftreinigung zu etablieren. Das ist zum einen der Einsatz anorganischer Materialien, die mit höheren Anschaffungskosten einhergehen, aber verbesserte Beständigkeiten und längere Lebensdauern ermöglichen. Diesbezüglich wird das geordnete, mesoporöse Siliziumdioxid COK-12 untersucht, welches zahlreiche Möglichkeiten bietet, die strukturellen und chemischen Eigenschaften einzustellen und dadurch optimierte Reinigungsergebnisse zu erzielen. Zum anderen wird die Kultivierung von natürlichen Pilzmaterialien als einfache, ökologische und ökonomische Alternative für die Entfernung von Schadstoffen untersucht. Für die gezielte Modifikation der Mesostruktur des COK-12 wird der Effekt der Einlagerung von p-Xylol als Quellmittel in verschiedenen Konzentrationen und die Kombination mit einem thermischen Alterungsschritt während der Synthese analysiert. Es werden mesozelluläre Schäume mit Tintenfassporen und maßgeblich vergrößerten Poreninnendurchmessern und -eingängen erzeugt, welche die Immobilisierung von größeren Substanzen und zugleich einen erhöhten Massetransport ermöglichen – wünschenswert zum Beispiel für Adsorptionsanwendungen. Zur Verbesserung der Adsorption des kationischen Farbstoffs Methylenblau aus wässriger Lösung wird Graphenoxid mittels Grafting auf thermisch gealtertes, großporiges COK-12 appliziert. Die zahlreichen sauerstoffhaltigen, funktionalen Oberflächengruppen mit negativer Ladung ermöglichen eine hohe Adsorptionskapazität des Materials, welche die des reinen COK-12 und vergleichbarer Kompositadsorbentien übersteigt und überdies unter simulierten Industrieabwasserbedingungen Bestand hat. Um die Exposition gegenüber Nanopulvern zu reduzieren und mechanisch stabile Siliziumdioxidmonolithe mit hierarchischer Porenstruktur aus Mikro-, Meso- und Makroporen für Filtrationsanwendungen zu erhalten, werden additivfreies Spark Plasma Sintern (SPS) und konventionelles Sintern von COK-12 untersucht. Für beide Sinterverfahren bleibt die Mesostruktur im analysierten Parameterbereich erhalten. Im Vergleich der Sinterverfahren geht die gleichzeitige Einwirkung von Druck und Temperatur während des SPS-Verfahrens mit stärkeren Verlusten der Porosität und Abweichungen vom theoretischen Gitter einher, während zugleich die Größe der Mesoporen und Gitterparameter besser erhalten bleiben. Auf Grund der besseren mechanischen Eigenschaften bei vergleichbarer Porosität sind die SPS-prozessierten Monolithe für die Filtration einer Öl-in-Wasser-Emulsion mittels Dead-End-Filtration geeignet. Abschätzungen der tatsächlichen Gaspermeabilität der COK-12 Monolithe verorten die Monolithe zudem in einem für die Aerosolfiltration geeigneten Permeabilitätsbereich. Um den Druckabfall zu reduzieren, scheint zukünftig eine höhere Makroporosität erstrebenswert. Als Alternative zu hochentwickelten, synthetischen Materialien wird die Eignung des Pilzes Fomes fomentarius als Biosorbens untersucht. Im Zentrum der Untersuchung steht der Einfluss der Wachstumsbedingungen auf die Adsorptionsleistung gegenüber Farbstoffen aus wässrigen Lösungen. Im Vergleich zu natürlichen Fruchtkörpern weisen die im Labor auf Hanfschäben bzw. in einem Flüssigmedium kultivierten Myzelien Unterschiede in der Zusammensetzung sowie Hyphengröße und -form auf, wodurch sich höhere Adsorptionsleistungen ergeben. Die Kultivierungsbedingungen von Pilzmaterialien können also genutzt werden, um die Eigenschaften und Adsorptionsleistungen anzupassen. Dabei ist die Nutzung günstigen, landwirtschaftlichen Abfalls als Wachstumssubstrat besonders zukunftsträchtig. Zusammenfassend zeigt diese Dissertation nachhaltigere Alternativen zu erdölbasierten Polymermaterialien für die Wasser- und Luftreinigung auf. Synthetisches, hoch technisiertes COK-12 sowie natürlicher, nachwachsender F. fomentarius werden als geeignete Materialien für herausfordernde und langfristige sowie einfache und ökonomische Reinigungsanwendungen präsentiert.
- Published
- 2023
- Full Text
- View/download PDF
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