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Synthesis of zinc-magnesium-titanium (Zn/Mg/Ti) oxide hybrid nanofibers and investigation of their effects on the photocatalytic degradation of textile dyes
Get PDFBu çalışmada, Zn ve Mg elementleri ile katkılanmış TiO₂ nanolifler sol-jel elektro çekim yöntemiyle başarıyla üretilmiş ve nanoliflerin yapısal, morfolojik, optik ve fotokatalitik özellikleri kapsamlı bir şekilde incelenmiştir. TiO₂ nanoliflere farklı oranlarda (%5, %15, %30) Zn, Mg ve Zn/Mg katkılanarak üretilen nanoliflerin SEM ve TEM analizleri incelenmiş, katkı oranı arttıkça lif morfolojisinde bozulmalar ve çaplarda artış yaşandığını gözlenmiştir. XRD ve Raman analizleri, Zn ve Mg katkılarının TiO₂ kristal fazında anatazdan rutile geçişi hızlandırdığını ortaya koymuştur. XPS analizleri, katkı elementlerinin başarıyla yüzeye dâhil edildiğini doğrulamıştır. PL analizleri, düşük katkı oranlarında rekombinasyon oranının azaldığını, yüksek oranlarda ise optik verimin düştüğünü göstermiştir. Fotokatalitik performans değerlendirmesi, katkı oranına bağlı olarak boya degradasyon verimliliğinde azalma olduğunu, en yüksek verimin %90,75 ile saf TiO₂'de elde edildiğini, Zn/Mg katkılı numunelerde ise en iyi sonucun %5 (Zn/Mg) ile %78,6 oranında elde edildiğini ortaya koymuştur. Ayrıca ATR-FTIR spektra ile degradasyon sonrası nanolif yüzeyindeki boya moleküllerinin yapısal değişiklikleri izlenmiştir. Elde edilen bulgular, Zn/Mg katkılı TiO₂ nanoliflerin, özellikle düşük katkı oranlarında, çevre dostu ve etkin fotokatalizörler olarak atık su arıtımı gibi alanlarda potansiyel taşıdığını göstermektedir.In this study, Zn- and Mg-doped TiO₂ nanofibers were successfully synthesized via the electrospinning method, and their structural, morphological, optical, and photocatalytic properties were systematically investigated. Nanofibers were produced with varying doping ratios (5%, 15%, and 30%) of Zn, Mg, and Zn/Mg. SEM and TEM analyses revealed that increasing dopant concentrations led to morphological irregularities and diameter growth in the nanofibers. XRD and Raman results indicated that Zn and Mg accelerated the anatase-to-rutile phase transformation. XPS analysis confirmed the successful incorporation of dopants onto the surface. PL spectroscopy showed that lower dopant concentrations reduced recombination rates, whereas higher concentrations diminished the optical performance. Photocatalytic performance evaluation revealed that the dye degradation efficiency decreased with increasing dopant concentration. The highest efficiency was obtained with pure TiO₂ at 90.75%, while among the Zn/Mg-doped samples, the best result was achieved with 5% (Zn/Mg) at 78.6%. Additionally, FTIR analysis were employed to examine post-degradation structural changes. Overall, the results suggest that Zn/Mg-doped TiO₂ nanofibers, particularly at low dopant concentrations, possess promising potential as environmentally friendly and efficient photocatalysts for wastewater treatment and similar applications
Synthesis of zinc-magnesium-titanium (Zn/Mg/Ti) oxide hybrid nanofibers and investigation of their effects on the photocatalytic degradation of textile dyes
No full textBu çalışmada, Zn ve Mg elementleri ile katkılanmış TiO₂ nanolifler sol-jel elektro çekim yöntemiyle başarıyla üretilmiş ve nanoliflerin yapısal, morfolojik, optik ve fotokatalitik özellikleri kapsamlı bir şekilde incelenmiştir. TiO₂ nanoliflere farklı oranlarda (%5, %15, %30) Zn, Mg ve Zn/Mg katkılanarak üretilen nanoliflerin SEM ve TEM analizleri incelenmiş, katkı oranı arttıkça lif morfolojisinde bozulmalar ve çaplarda artış yaşandığını gözlenmiştir. XRD ve Raman analizleri, Zn ve Mg katkılarının TiO₂ kristal fazında anatazdan rutile geçişi hızlandırdığını ortaya koymuştur. XPS analizleri, katkı elementlerinin başarıyla yüzeye dâhil edildiğini doğrulamıştır. PL analizleri, düşük katkı oranlarında rekombinasyon oranının azaldığını, yüksek oranlarda ise optik verimin düştüğünü göstermiştir. Fotokatalitik performans değerlendirmesi, katkı oranına bağlı olarak boya degradasyon verimliliğinde azalma olduğunu, en yüksek verimin %90,75 ile saf TiO₂'de elde edildiğini, Zn/Mg katkılı numunelerde ise en iyi sonucun %5 (Zn/Mg) ile %78,6 oranında elde edildiğini ortaya koymuştur. Ayrıca ATR-FTIR spektra ile degradasyon sonrası nanolif yüzeyindeki boya moleküllerinin yapısal değişiklikleri izlenmiştir. Elde edilen bulgular, Zn/Mg katkılı TiO₂ nanoliflerin, özellikle düşük katkı oranlarında, çevre dostu ve etkin fotokatalizörler olarak atık su arıtımı gibi alanlarda potansiyel taşıdığını göstermektedir.In this study, Zn- and Mg-doped TiO₂ nanofibers were successfully synthesized via the electrospinning method, and their structural, morphological, optical, and photocatalytic properties were systematically investigated. Nanofibers were produced with varying doping ratios (5%, 15%, and 30%) of Zn, Mg, and Zn/Mg. SEM and TEM analyses revealed that increasing dopant concentrations led to morphological irregularities and diameter growth in the nanofibers. XRD and Raman results indicated that Zn and Mg accelerated the anatase-to-rutile phase transformation. XPS analysis confirmed the successful incorporation of dopants onto the surface. PL spectroscopy showed that lower dopant concentrations reduced recombination rates, whereas higher concentrations diminished the optical performance. Photocatalytic performance evaluation revealed that the dye degradation efficiency decreased with increasing dopant concentration. The highest efficiency was obtained with pure TiO₂ at 90.75%, while among the Zn/Mg-doped samples, the best result was achieved with 5% (Zn/Mg) at 78.6%. Additionally, FTIR analysis were employed to examine post-degradation structural changes. Overall, the results suggest that Zn/Mg-doped TiO₂ nanofibers, particularly at low dopant concentrations, possess promising potential as environmentally friendly and efficient photocatalysts for wastewater treatment and similar applications
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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