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Solid phase extraction prior to atomic absorption spectrometric determination of some trace metal ions
Get PDFBu tezin, veri tabanı üzerinden yayınlanma izni bulunmamaktadır. Yayınlanma izni olmayan tezlerin basılı kopyalarına Üniversite kütüphaneniz aracılığıyla (TÜBESS üzerinden) erişebilirsiniz.Fen Bilimleri Enstitüsü, Kimya Ana Bilim DalıÖZET BAZI ESER METAL İYONLARININ ATOMİK ABSORPSIYON SPEKTROMETRİK TAYİNLERİ ÖNCESİ KATI FAZ EKSTRAKSİYONLARI NARİN İbrahim Niğde Üniversitesi Fen Bilimleri Enstitüsü Kimya Anabilim Dalı Danışman : Prof. Dr. Kadriye KAYAKIRILMAZ Ortak Danışman : Doç. Dr. Mustafa SOYLAK Mart 2002, 158 sayfa Bu çalışmada, altı elementin (nikel(II), kadmiyum(II), kobalt(II), bakır(II), kurşun(II) ve krom(III)), alevli AAS ile tayinleri öncesi Amberlite XAD-16-PAN şelat reçinesi dolgulu mini kolonda zenginleştirilmesini esas alan yeni bir yöntem geliştirildi. Yeni sentezlenen şelat reçinesi Amberlite XAD-16 reçinesine l-(2- piridilazo)-2-naftol (PAN) kimyasal olarak bağlanmasıyla sentezlendi. Sentezlenen şelat reçinesi; FTIR, elementel analiz, termogravimetrik analiz ve taramalı elektron mikroskop yöntemleri ile karakterize edildi. Yöntemin optimizasyonu; örnek çözeltisinin pH'sı, reçine miktarı, örnek hacmi ve yabancı iyon etkileri gibi çeşitli analitik parametreler araştırılarak yapıldı. Geliştirilen yöntem Niğde ilinden toplanan çeşme suyu örneklerine uygulandı. Tezin ikinci bölümünde, krom (III) ve krom (VI) türlemesi için yeni bir yöntem geliştirildi. Geliştirilen yöntemin esasını Cr(VI)-APDC selatinin Ambersorb 563 reçinesi dolgulu mini kolonda tutunması oluşturmaktadır. Krom (III) iyonları H2O2 ile krom (Vl)'ya yükseltgendikten sonra, geliştirilen yöntem uygulanarak toplam krom miktarları tayin edildi. Krom(III) düzeyleri, toplam kromdan krom(VI) iyonları çıkartılarak hesaplandı. Kantitatif krom türlemesi için örnek çözeltisinin pH'sı, ligand miktarı, örnek hacmi gibi analitik parametreler araştırıldı. Geri kazanım değerleri % 95 'den fazla bulundu. Doğal suların ana bileşen iyonları ve bazı metal iyonlarının yönteme bozucu etkilerinin olmadığı belirlendi. Gözlenebilme sınırı Cr(VI) için 2,70 (ig/L olarak bulundu(3 an.ı). Önerilen metot Bor Deri Sanayi bölgesinden toplanan deri atık suyunun krom türlemesine başarıyla uygulandı. IIIAnahtar Sözcükler : Selat Reçinesi, Amberlite XAD-16, Türleme, Krom, Katı Faz Ekstraksiyonu, Atık Su Analizi, APDC, Zenginleştirme IVSUMMARY SOLID PHASE EXTRACTION PRIOR TO ATOMIC ABSORPTION SPECTROMETRY DETERMINATION OF SOME TRACE METAL IONS NARİN Ibrahim Niğde University Graduate School of Natural and Applied Sciences Department of Chemistry Supervisor : Prof. Dr. Kadriye KAYAKIRILMAZ Co-Advisor : Doç. Dr. Mustafa SOYLAK March 2002, 158 pages In this study, a new method based on enrichment of six elements was developed an a column filled with Amberlite XAD-16-PAN chelating resin before their determinations by flame AAS. A new chelating resin was synthesized by coupling Amberlite XAD-16 resin with 1 -(2-pyridylozo)-2-naphthol through an azo spacer. The synthesized chelating resin was characterized by IR spectra, elemental analyses, thermogravimetric analysis and scanning electron microscope techniques. To optimize the method, the effects of various analytical parameters such as pH of sample solutions, amount of resin, volume of sample and diverse ions were investigated. The method was applied to tap water samples collected from Nigde. In the second part of the thesis, a simple method has been established for speciation of chromium (III) and chromium (VI). The method is based on the solid phase extraction of the Cr(VI)-APDC chelate on the Ambersorb 563 carbonaceous resin filled mini column. After oxidation of chromium (III) to chromium(VI) by using hydrojen peroxide, the \ method was applied to the determination of total chromium. The level of chromium (III) is calculated by difference of total chromium and chromium (VI) concentrations. The influence of analytical parameters including pH, amounts of reagents, sample volume on the quantitative speciation values of chromium were investigated. Recoveries of more than % 95 were found. No interferes due to major components of the natural waters samples and some metal ions were observed. The dedections limit based on the 3 on.i criterion was 2,70 ug/L for chromium (VI). The presented method was applied for the speciation of Vchromium in the tannery wastewater samples from Bor Organized Industrial Region-Niğde with satisfactory result. Key Words: Chelating Resin, Amberlite XAD-16, Speciation, Chromium, Solid Phase Extraction, Waste Water Analysis, APDC, Enrichment V
Preconcentration and determination of some food dyes and trace elements in different food products
No full textBu çalışmanın büyük bir kısmında; sunset yellow, tartrazin ve allura red gıda boyalarının tayini için Amberlite XAD-1180 ve Amberlite XAD-16 ticari polimerik reçinelerini kullanarak ayrı ayrı katı faz ekstraksiyon metotları geliştirilmiştir. Metotların pH, örnek ve eluent akış hızları, örnek hacimleri ve eluent türleri gibi parametreleri incelenmiş ve optimum koşullar araştırılmıştır. Optimum koşullarda metotların gözlenebilme ve tayin sınırları belirlenmiş, yabancı iyon ve boyaların analize etkisi araştırılmıştır. Geliştirilen tayin metotları ile çeşitli gıda ve ilaç örneklerinde sunset yellow, tartrazin ve allura red tayini analit ilavesi tekniği ile yapılmıştır. Yine bu çalışmada Nevşehir ve Niğde yörelerinde doğal olarak yetişen yenilebilir 16 farklı tür mantar örneği toplanmıştır. Mantar örnekleri mikrodalga yakma ünitesinde çözünürleştirildikten sonra Cu, Mn, Zn, Fe, Bi, Cd, Pb, Cr ve Ni içerikleri alevli atomik absorpsiyon spektrofotometresi ile tayin edilmiştir. Sonuçlar kuru ağırlık esas alınarak (µg/g) verilmiş ve literatürde daha önceden eser metal içeriği tayin edilmiş mantarların analizleri ile karşılaştırılmıştır.In a major part of this study, solid phase extraction methods were developed individually for determination of sunset yellow, tartrazine and allura red dyes with using commercial two different polymeric resins. Parameters of the methods including pH, sample and eluent flow rates, sample volume and type of eluents were investigated and optimized. Under the optimum conditions detection limits and determination limits of the methods were determined. Effects of foreign ions and dyes were also investigated at the optimum conditions. Determinations of sunset yellow, tartrazine and allura red in the different food products and some pharmaceutical samples were carried out with addition of analyte technique. In this work, indigenous 16 different species mushroom samples were collected from regions of Nev?ehir and Niğde. Trace metal contents (Cu, Mn, Zn, Fe, Bi, Cd, Pb, Cr and Ni) of mushroom samples were determined with flame atomic absorption spectrometry after microwave digestion. Analysis results were given on the basis of dry weight (µg/g) and compared with previously reported mushroom studies
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
Preconcentration of lead(II) ion in aqueus phase by miceller system extraction and determination
Get PDFFen Bilimleri Enstitüsü, Kimya Ana Bilim DalıÖZET SULU ORTAMDA BULUNAN KURŞUN (II) İYONLARININ MİSELLER SİSTEM EKSTRAKSİYONUYLA ZENGİNLEŞTİRİLMESİ VE TAYİNİ SÜRME, Yavuz Niğde Üniversitesi Fen Bilimleri Enstitüsü Kimya Anabilim Dalı Danışman: : Prof. Dr. Hüseyin YÜRÜK İkinci Danışman: : Doç. Dr. İbrahim NARİN Temmuz 2005, 78 sayfa Bu çalışmada sulu ortamda bulunan kurşun (II) iyonlarının miseller sistem ekstraksiyonu yöntemiyle zenginleştirilmesi ve atomik absorpsiyon spektrometresi ile tayini için optimum şartlar incelenmiştir. Araştırmada öncelikle sulu ortamda bulunan kurşun iyonları brillant creasyl blue ligandı ile kompleksleştirildikten sonra oluşan bu kompleksleri miseller fazda zenginleştirmek için miseller sistem ekstraksiyon yöntemi optimize edilmiştir. Optimizasyon, çözelti pH'sı, sıcaklık, ligand ve yüzey aktif madde miktarı, bekleme zamanı ve çözücü viskozitesi gibi parametrelerle gerçekleştirilmiştir. Miseller faza zenginleştirilen kurşun (II)-BCB kompleksleri metanolde İM HNO3 ile çözülüp seyreltildikten sonra kurşun miktarları atomik absorpsiyon spektrometresi ile tayin edilmiştir. Geliştirilen yöntemle bazı maden ve içme sulan ile sediment örneklerinde bulunan kurşun miktarları tayin edilmiştir. Anahtar Kelimeler: Atomik Absorpsiyon Spektrometrisi, Misel Ortam Ekstraksiyonu, Zenginleştirme, Triton X- 1 1 4, Brillant Creasyl Blue, Kurşun mABSTRACT PRECONCENTRATION OF LEAD (II) ION IN AQUEUS PHASE BY MICELLER SYSTEM EXTRACTION AND DETERMINATION SÜRME, Yavuz Niğde University Graduated School of Natural and Applied Sciences Department of Chemistry Supervisor: : Prof. Dr. Hüseyin YÜRÜK Co-Advisor: : Doç. Dr. İbrahim NARİN July 2005, 78 pages In this study preconcentration of lead (II) ions in aqueus solution by miceller system extraction and determination with atomic absorption spectrometry have been investigated. Firstly, the Pb (II) ions in aqueus media have been complexed with brillant creasyl blue ligand then the miceller system extraction which is used for preconcentration of Pb (H)-BCB complexes into the miceller media, is optimized. The optimization have been made with the parameters of solution pH, temperature, ligand and surfactant quantities, incubation time and solvent viscosity. After the Pb (II)-BCB complexes which preconcentrated to miceller phase these complexes were solved with İM HNO3 in methanol and diluted with İM HNO3 in aqua, Pb (IT) levels determined by flame atomic absorption spectrometry. Pb levels of, mineral waters and sediment samples have been determined by the developed method. Key Words: Atomic Absorption Spectrometry, Micelle Mediated Extraction, Preconcentration, Triton X-l 14, Brillant Creasyl Blue, Lead I
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
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