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Atık Termoplastiklerin Pirolizinden Meydana Gelen Gaz Ürünün Adsorpsiyon Prosesi ile Arıtımı
No full textBu çalışma kapsamında piroliz yan ürünlerinin değerlendirilmesi için alternatif yaklaşımlar sergilenirken, aynı zamanda ekonomik açıdan önemi olmayan ve toksik özellikler sergileyen gaz ürünler üzerine odaklanılarak çevresel hasarın minimum düzeye indirgenmesi amaçlanmıştır. Bu doğrultuda yapılan deneysel çalışmalar ile HDPE, LDPE ve PP türü plastik atıkların sırasıyla 500, 600 ve 700 °C hedef sıcaklıklarında piroliz işlemleri gerçekleştirilmiştir. Bu piroliz işlemlerinden elde edilen katı ürün (kok), aktivasyon prosedürüne uğratılarak, uygulamada en önemli adsorban olan aktif karbon (AC) ile kıyaslanmıştır. Daha sonrasında elde edilen bu adsorbanın, yine ilgili plastik türünün pirolizinden elde edilen gaz ürünü adsorpsiyon verimi analitik metodlarla incelenmiştir. Çalışma sonucunda piroliz gaz ürününün adsorpsiyonunda; HDPE, LDPE ve PP pirolizinde hedef sıcaklıklar için sırasıyla, %60-80, %40-90, %40-80 oranında verimler elde edilmiştir. Piroliz koklarından oluşturulan adsorpsiyon kolonlarında, yine piroliz gazlarının tutunmasında HDPE türü aktivasyonlu kokların en yüksek verimle adsorbe ettiği bileşenler 500 °C, 600 °C ve 700 °C'de sırasıyla toluen, stiren ve etilbenzen olmuştur. LDPE'de bu bileşenler sırasıyla pentan, oktan ve benzen olurken, PP türü için sırasıyla toluen, stiren ve stiren olmuştur. BET analizi sonuçlarıyla bir değerlendirme yapıldığında aktivasyon metoduyla birlikte kok türlerinde yüzey alanı noktasında aktivasyonsuz hallerine göre HDPE`de 18 kat LDPE`de 70 kat ve PP`de 20 kat artış görülmüştür. Bu tez çalışmasıyla birlikte plastik atıkların piroliz yöntemiyle bertarafı sonrası ortaya çıkan yan ürünlerden olan kokun kullanımına alternatif bir yol sunulurken, bir diğer piroliz ürünü olan ve toksik özellikleri bilinen pirolitik gazın adsorpsiyon yöntemi ile arıtımı sağlanmıştır.Within the scope of this study, it is aimed to minimize the environmental damage by focusing on gas products that are economically insignificant and exhibit toxic properties while exhibiting alternative approaches for the evaluation of pyrolysis by-products. With the experimental studies carried out in this direction, pyrolysis processes of HDPE, LDPE and PP type plastic wastes were carried out at target temperatures of 500, 600 and 700 ° C, respectively. The solid product (char) obtained from these pyrolysis processes was subjected to the activation procedure and compared with activated carbon (AC), the most important adsorbent in the literature. Then, the adsorption efficiency of this adsorbent obtained from the pyrolysis of the related plastic type was investigated by analytical methods. At the end of the study, in the adsorption of the pyrolysis gas product; For HDPE, LDPE and PP pyrolysis, yields of 60-80%, 40-90% and 40-80% were obtained, respectively, for target temperatures. In the adsorption columns formed from pyrolysis char, HDPE-type activated char adsorbed with the highest efficiency in the holding of pyrolysis gases were toluene, styrene and ethylbenzene at 500, 600 and 700 °C, respectively. In LDPE, these components were pentane, octane and benzene, respectively, while for the PP type, they were toluene, styrene and styrene, respectively. When an evaluation was made with the results of the BET analysis, an 18-fold increase in HDPE and a 20-fold increase in LDPE was observed at the surface area of char species compared to their non-activation state with the activation method. With this thesis study, an alternative way to the use of char, which is one of the by-products emerging after the disposal of plastic wastes by pyrolysis method, was provided, while the treatment of pyrolytic gas, which is another pyrolysis product and known toxic properties, was provided by adsorption method
Investigation of the Use of Casting and Mining Industry Waste in Concrete Instead of Aggregate
No full textGünümüzde, atık ve artık olarak ortaya çıkan malzemelerin yeniden kullanımı ve geri dönüşümü konusunda yoğun olarak çalışılmaktadır. Bu çalışmalarda atıklardan yeni ürünler elde edilmesi veya bunların katkı maddesi olarak kullanılması amaçlanmaktadır. Atıkların yeniden kullanımı veya geri dönüşümü; sınırlı olan doğal kaynakların kullanımını azaltarak, doğanın tahrip edilmesini önlemekte, üretimde verimliliği artırmakta ve atık depolanması sonucu oluşacak çevre problemlerini en aza indirmektedir. Doğal kaynakların daha az tüketilmesi, çevre kirliliğinin daha aza indirgenmesi ve enerji maliyetlerinin azaltılması amacıyla betonun bileşiminde endüstriyel atık kullanımı gün geçtikçe daha fazla ilgi çeken bir konudur. Bu yüksek lisans tez çalışması ile önemli bir çevresel sorun olan atık döküm kumu ve atık vermikülit için yeni bir değerlendirme alanı araştırılabileceği gibi, beton üretimi sırasında kullanılan agreganın kullanımı da azaltılacağı için bu agregaların temini sırasında meydana gelen doğal kaynakların tahribatının da azaltılması hedeflenmiştir. Bu amaçla, saf ve atık döküm kumu ve atık vermikülitin önemli bir yapı malzemesi olan beton içerisinde değerlendirilmesi çalışmaları gerçekleştirilmiştir. Bu atıklar %5, %10 ve %20 oranlarında beton içerisindeki agrega ile yer değiştirilerek betonun işlenebilirlik, Taramalı elektron mikroskobu (SEM), FTIR (Fourier Transform Infrared) spektrofotometresi, Termogravimetrik analiz (TGA), X-ışınları difraktometresi (XRD) ve basınç dayanımı analizleri gerçekleştirilmiştir. Çalışma sonunda, üç katkı türününde betonun işlenebilirliğini ve betonun termal özelliklerini olumlu yönde geliştirdiği, minerojik yapı tespiti için yapılan XRD analizi bulgularına göre saf ve atık döküm kumu katkısının betonun hidratasyonunu olumlu yönde etkilediği sonucu elde edilmiştir.Today, intensive work is being done on the reuse and recycling of waste and residual materials. In these studies, it is aimed to obtain new products from wastes or to use them as additives. Reuse or recycling of waste; By reducing the use of limited natural resources, it prevents the destruction of nature, increases efficiency in production and minimizes environmental problems that may arise as a result of waste storage. In order to consume less natural resources, reduce environmental pollution and reduce energy costs, the use of industrial waste in the composition of concrete is an issue that attracts more and more attention day by day. With this master's thesis, a new evaluation area for waste casting sand and waste vermiculite, which is an important environmental problem, can be researched, and it is aimed to reduce the destruction of natural resources that occur during the supply of these aggregates, since the use of aggregate used during concrete production will be reduced. For this purpose, studies were carried out to evaluate pure and waste casting sand and waste vermiculite in concrete, which is an important building material. These wastes are replaced with the aggregate in the concrete at the rates of 5%, 10% and 20%, and the workability of the concrete, Scanning electron microscope (SEM), FTIR (Fourier Transform Infrared) spectrophotometer, Thermogravimetric analysis (TGA), X-ray diffractometry (XRD) and pressure strength analyzes were carried out. At the end of the study, it was concluded that the workability of the concrete and the thermal properties of the concrete were improved in three admixture types, and the pure and waste casting sand additive positively affected the hydration of the concrete, according to the XRD analysis findings for the determination of the mineralogical structure
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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