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Mustafa Soylak - One of the best experts on this subject based on the ideXlab platform.

  • separation preconcentration of silver i and lead ii in environmental samples on Cellulose Nitrate membrane filter prior to their flame atomic absorption spectrometric determinations
    Journal of Hazardous Materials, 2007
    Co-Authors: Mustafa Soylak
    Abstract:

    Abstract An enrichment method for trace amounts of Ag(I) and Pb(II) has been established prior to their flame atomic absorption spectrometric determinations. The preconcentration/separation procedure is based on chelate formation of Ag(I) and Pb(II) with ammonium pyrrolidine dithiocarbamate (APDC) and on retention of the chelates on Cellulose Nitrate membrane filter. The influences of some analytical parameters including pH and amounts of reagent, etc. on the recoveries of analytes were investigated. The effects of interferic ions on the quantitative recoveries of analytes were also examined. The detection limits (k = 3, N = 11) were 4.6 μg L−1 for silver(I) and 15.3 μg L−1 for lead(II). The relative standard deviations (R.S.D.) of the determinations for analyte ions were below 3%. The method was applied to environmental samples for the determination of analyte ions with satisfactory results (recoveries >95%).

  • separation preconcentration of cu ii fe iii pb ii co ii and cr iii in aqueous samples on Cellulose Nitrate membrane filter and their determination by atomic absorption spectrometry
    Analytical Letters, 2002
    Co-Authors: Aslihan Karatepe, Mustafa Soylak, Latif Elci
    Abstract:

    ABSTRACT A simple enrichment method for trace amounts of Cu(II), Fe(III), Pb(II), Co(II) and Cr(III) has been established. The preconcentration/separation procedure is based on chelate formation of the analyte metals with benzopurpurine 4B and on retention of the chelates on Cellulose Nitrate membrane filter. After completely dissolving the Cellulose Nitrate membrane and analyte ions by 500 µL of nitric acid at 85°C on a hood, metal determinations were performed by flame atomic absorption spectrometry. The influences of some analytical parameters including pH, types of membrane filters, amounts of reagent etc. on the recoveries of copper, iron, lead, cobalt and chromium were investigated. The detection limits of the analyte ions (k = 3, N = 21) were varying 1.9 µg/L for cobalt to 10.5 µg/L for iron. The method was applied to natural water samples for the determination of analyte ions with satisfactory results (recoveries > 95%, RSD < 10%). The relative standard deviations (RSD) of the determinations for a...

  • preconcentration of cr iii co ii cu ii fe iii and pb ii as calmagite chelates on Cellulose Nitrate membrane filter prior to their flame atomic absorption spectrometric determinations
    Talanta, 2002
    Co-Authors: Mustafa Soylak, Umit Divrikli, Latif Elci, Mehmet Dogan
    Abstract:

    Abstract A method for the preconcentration and determination of Cr(III), Co(II), Cu(II), Fe(III) and Pb(II) ions by atomic absorption spectrometry has been described. The method was based the collection of metal–calmagite complexes on a soluble Cellulose Nitrate membrane filter. The detection of the solution was obtained by flame atomic absorption spectrometry (FAAS) after completely dissolving the membrane with 0.5 ml of nitric acid at 80 °C. The metal ions were recovered quantitatively at pH 8. Various factors which affect the collection and determination of metal ions such as, type and size of the membrane filter, solvent for dissolution of the species retained on the filter were investigated. The detection limits were varying 0.06 μg l−1 for Cu to 2.5 μg l−1 for Cr. An application of the proposed method for analyte ions in mineral and tap water samples was also described with satisfactory results (recoveries >95%, relative standard deviations

  • preconcentration of cr iii co ii cu ii fe iii and pb ii as calmagite chelates on Cellulose Nitrate membrane filter prior to their flame atomic absorption spectrometric determinations
    Talanta, 2002
    Co-Authors: Mustafa Soylak, Umit Divrikli, Latif Elci, Mehmet Dogan
    Abstract:

    A method for the preconcentration and determination of Cr(III), Co(II), Cu(II), Fe(III) and Pb(II) ions by atomic absorption spectrometry has been described. The method was based the collection of metal–calmagite complexes on a soluble Cellulose Nitrate membrane filter. The detection of the solution was obtained by flame atomic absorption spectrometry (FAAS) after completely dissolving the membrane with 0.5 ml of nitric acid at 80 °C. The metal ions were recovered quantitatively at pH 8. Various factors which affect the collection and determination of metal ions such as, type and size of the membrane filter, solvent for dissolution of the species retained on the filter were investigated. The detection limits were varying 0.06 gl − 1 for Cu to 2.5 gl − 1 for Cr. An application of the proposed method for analyte ions in mineral and tap water samples was also described with satisfactory results (recoveries 95%, relative standard deviations 10%). © 2002 Elsevier Science B.V. All rights reserved.

Mehmet Dogan - One of the best experts on this subject based on the ideXlab platform.

  • preconcentration of cr iii co ii cu ii fe iii and pb ii as calmagite chelates on Cellulose Nitrate membrane filter prior to their flame atomic absorption spectrometric determinations
    Talanta, 2002
    Co-Authors: Mustafa Soylak, Umit Divrikli, Latif Elci, Mehmet Dogan
    Abstract:

    Abstract A method for the preconcentration and determination of Cr(III), Co(II), Cu(II), Fe(III) and Pb(II) ions by atomic absorption spectrometry has been described. The method was based the collection of metal–calmagite complexes on a soluble Cellulose Nitrate membrane filter. The detection of the solution was obtained by flame atomic absorption spectrometry (FAAS) after completely dissolving the membrane with 0.5 ml of nitric acid at 80 °C. The metal ions were recovered quantitatively at pH 8. Various factors which affect the collection and determination of metal ions such as, type and size of the membrane filter, solvent for dissolution of the species retained on the filter were investigated. The detection limits were varying 0.06 μg l−1 for Cu to 2.5 μg l−1 for Cr. An application of the proposed method for analyte ions in mineral and tap water samples was also described with satisfactory results (recoveries >95%, relative standard deviations

  • preconcentration of cr iii co ii cu ii fe iii and pb ii as calmagite chelates on Cellulose Nitrate membrane filter prior to their flame atomic absorption spectrometric determinations
    Talanta, 2002
    Co-Authors: Mustafa Soylak, Umit Divrikli, Latif Elci, Mehmet Dogan
    Abstract:

    A method for the preconcentration and determination of Cr(III), Co(II), Cu(II), Fe(III) and Pb(II) ions by atomic absorption spectrometry has been described. The method was based the collection of metal–calmagite complexes on a soluble Cellulose Nitrate membrane filter. The detection of the solution was obtained by flame atomic absorption spectrometry (FAAS) after completely dissolving the membrane with 0.5 ml of nitric acid at 80 °C. The metal ions were recovered quantitatively at pH 8. Various factors which affect the collection and determination of metal ions such as, type and size of the membrane filter, solvent for dissolution of the species retained on the filter were investigated. The detection limits were varying 0.06 gl − 1 for Cu to 2.5 gl − 1 for Cr. An application of the proposed method for analyte ions in mineral and tap water samples was also described with satisfactory results (recoveries 95%, relative standard deviations 10%). © 2002 Elsevier Science B.V. All rights reserved.

Irma Bowen Historic Clothing G. Collection - One of the best experts on this subject based on the ideXlab platform.

  • Comb, yellow with brass, late 19th century, front view
    University of New Hampshire Scholars\u27 Repository, 2019
    Co-Authors: Irma Bowen Historic Clothing G. Collection
    Abstract:

    Late 19th century. Yellow celluloid hair comb with a cast brass scrollwork decoration and four teeth. Celluloid is an early plastic that mixed Cellulose Nitrate with a plasticizer, which is now leaching out and degrading the material, breaking it down into crystals and corroding the brass.https://scholars.unh.edu/bowen_collection/1151/thumbnail.jp

  • Comb, yellow with brass, late 19th century, detail of crystallization
    University of New Hampshire Scholars\u27 Repository, 2019
    Co-Authors: Irma Bowen Historic Clothing G. Collection
    Abstract:

    Late 19th century. Yellow celluloid hair comb with a cast brass scrollwork decoration and four teeth. Celluloid is an early plastic that mixed Cellulose Nitrate with a plasticizer, which is now leaching out and degrading the material, breaking it down into crystals and corroding the brass.https://scholars.unh.edu/bowen_collection/1152/thumbnail.jp

  • Comb, yellow with rhinestones, late 19th century, detail of crystallization
    University of New Hampshire Scholars\u27 Repository, 2019
    Co-Authors: Irma Bowen Historic Clothing G. Collection
    Abstract:

    Late 19th century. Yellow celluloid hair comb with eight rows of yellow rhinestones radiating out from a central point, and four teeth which have now broken off due to degradation of the material. Celluloid is an early plastic that mixed Cellulose Nitrate with a plasticizer, which is now leaching out and degrading the material, breaking it down into crystals.https://scholars.unh.edu/bowen_collection/1150/thumbnail.jp

  • Comb, yellow with rhinestones, late 19th century, front view
    University of New Hampshire Scholars\u27 Repository, 2019
    Co-Authors: Irma Bowen Historic Clothing G. Collection
    Abstract:

    Late 19th century. Yellow celluloid hair comb with eight rows of yellow rhinestones radiating out from a central point, and four teeth which have now broken off due to degradation of the material. Celluloid is an early plastic that mixed Cellulose Nitrate with a plasticizer, which is now leaching out and degrading the material, breaking it down into crystals.https://scholars.unh.edu/bowen_collection/1191/thumbnail.jp

Maria Joao Melo - One of the best experts on this subject based on the ideXlab platform.

  • novel markers to early detect degradation on Cellulose Nitrate based heritage at the submicrometer level using synchrotron uv vis multispectral luminescence
    Scientific Reports, 2021
    Co-Authors: Artur Neves, A M Ramos, Maria Elvira Callapez, Robert Friedel, Matthieu Refregiers, Mathieu Thoury, Maria Joao Melo
    Abstract:

    Cellulose Nitrate (CN) is an intrinsically unstable material that puts at risk the preservation of a great variety of objects in heritage collections, also posing threats to human health. For this reason, a detailed investigation of its degradation mechanisms is necessary to develop sustainable conservation strategies. To investigate novel probes of degradation, we implemented deep UV photoluminescence micro spectral-imaging, for the first time, to characterize a corpus of historical systems composed of Cellulose Nitrate. The analysis of cinematographic films and everyday objects dated from the nineteenth c./early twentieth c. (Perlov's collection), as well as of photo-aged CN and celluloid references allowed the identification of novel markers that correlate with different stages of CN degradation in artworks, providing insight into the role played by plasticizers, fillers, and other additives in stability. By comparison with photoaged references of CN and celluloid (70% CN and 30% camphor), it was possible to correlate camphor concentration with a higher rate of degradation of the cinematographic films. Furthermore, the present study investigates, at the sub-microscale, materials heterogeneity that correlates to the artworks' history, associating the different emission profiles of zinc oxide to specific color formulations used in the late nineteenth and early twentieth centuries.

  • a diagnostic tool for assessing the conservation condition of Cellulose Nitrate and acetate in heritage collections quantifying the degree of substitution by infrared spectroscopy
    Heritage Science, 2020
    Co-Authors: Sofia Nunes, Artur Neves, A M Ramos, Francesca Ramacciotti, Eva Marisole Angelin, Elia Roldao, Nadja Wallaszkovits, Alfonso Alejo Armijo, Maria Joao Melo
    Abstract:

    Cellulose Nitrate and acetate are materials at risk in heritage collections because it is not possible to predict the evolution of their conservation state over time. Knowing that the degree of substitution (DS) of these materials correlates with their state of conservation because the fundamental degradation mechanism is hydrolysis, in this work, DS was measured in historical objects and artworks. Infrared spectra were used to develop and optimize calibration curves for Cellulose Nitrate and acetate references that were next applied to calculate DS values of heritage objects. The extent of hydrolysis measured, with this tool, correlated well with the physical deterioration assessed through the sample hardness (Shore A) which was measured with a Durometer. Calibration curves were optimized in reference materials by Attenuated Total Reflectance (ATR-FTIR) and Micro Fourier Transform Infrared Spectroscopy (μFTIR). The DS values of the AC reference materials was previously calculated by nuclear magnetic resonance spectroscopy. The calibration curves were obtained plotting DS as a function of the ratio between a reference peak (which does not suffer relevant changes during degradation) and selected peaks that monitor the degradation for Cellulose acetate and Nitrate polymers (avoiding the interference of plasticizers). The reference peak for both was the COC stretching mode (νCOC). The probe peak was, for Cellulose Nitrate, the NO2 asymmetric stretching (νaNO2) and, for Cellulose acetate, the OH stretching mode (νOH). This ratio was then applied to calculate DS values of historical materials, in good and poor conservation condition; in situ by ATR, and in micro-samples collected from artworks by μFTIR. This selection comprises cinematographic and photographic films dated from the 1890s to the 1960s, and contemporary works of art made with Cellulose acetate sheets by Portuguese artist Jose Escada dated from the 1960s. Finally, by comparison with the original estimated DS values, we show how this tool permits to define the state of degradation of these complex polymer matrixes. Thus, establishing the quantification of the DS as a novel tool to monitor the degradation of Cellulose ester plastics, contributing in this way for a sustainable preservation of an irreplaceable heritage.

Latif Elci - One of the best experts on this subject based on the ideXlab platform.

  • separation preconcentration of cu ii fe iii pb ii co ii and cr iii in aqueous samples on Cellulose Nitrate membrane filter and their determination by atomic absorption spectrometry
    Analytical Letters, 2002
    Co-Authors: Aslihan Karatepe, Mustafa Soylak, Latif Elci
    Abstract:

    ABSTRACT A simple enrichment method for trace amounts of Cu(II), Fe(III), Pb(II), Co(II) and Cr(III) has been established. The preconcentration/separation procedure is based on chelate formation of the analyte metals with benzopurpurine 4B and on retention of the chelates on Cellulose Nitrate membrane filter. After completely dissolving the Cellulose Nitrate membrane and analyte ions by 500 µL of nitric acid at 85°C on a hood, metal determinations were performed by flame atomic absorption spectrometry. The influences of some analytical parameters including pH, types of membrane filters, amounts of reagent etc. on the recoveries of copper, iron, lead, cobalt and chromium were investigated. The detection limits of the analyte ions (k = 3, N = 21) were varying 1.9 µg/L for cobalt to 10.5 µg/L for iron. The method was applied to natural water samples for the determination of analyte ions with satisfactory results (recoveries > 95%, RSD < 10%). The relative standard deviations (RSD) of the determinations for a...

  • preconcentration of cr iii co ii cu ii fe iii and pb ii as calmagite chelates on Cellulose Nitrate membrane filter prior to their flame atomic absorption spectrometric determinations
    Talanta, 2002
    Co-Authors: Mustafa Soylak, Umit Divrikli, Latif Elci, Mehmet Dogan
    Abstract:

    Abstract A method for the preconcentration and determination of Cr(III), Co(II), Cu(II), Fe(III) and Pb(II) ions by atomic absorption spectrometry has been described. The method was based the collection of metal–calmagite complexes on a soluble Cellulose Nitrate membrane filter. The detection of the solution was obtained by flame atomic absorption spectrometry (FAAS) after completely dissolving the membrane with 0.5 ml of nitric acid at 80 °C. The metal ions were recovered quantitatively at pH 8. Various factors which affect the collection and determination of metal ions such as, type and size of the membrane filter, solvent for dissolution of the species retained on the filter were investigated. The detection limits were varying 0.06 μg l−1 for Cu to 2.5 μg l−1 for Cr. An application of the proposed method for analyte ions in mineral and tap water samples was also described with satisfactory results (recoveries >95%, relative standard deviations

  • preconcentration of cr iii co ii cu ii fe iii and pb ii as calmagite chelates on Cellulose Nitrate membrane filter prior to their flame atomic absorption spectrometric determinations
    Talanta, 2002
    Co-Authors: Mustafa Soylak, Umit Divrikli, Latif Elci, Mehmet Dogan
    Abstract:

    A method for the preconcentration and determination of Cr(III), Co(II), Cu(II), Fe(III) and Pb(II) ions by atomic absorption spectrometry has been described. The method was based the collection of metal–calmagite complexes on a soluble Cellulose Nitrate membrane filter. The detection of the solution was obtained by flame atomic absorption spectrometry (FAAS) after completely dissolving the membrane with 0.5 ml of nitric acid at 80 °C. The metal ions were recovered quantitatively at pH 8. Various factors which affect the collection and determination of metal ions such as, type and size of the membrane filter, solvent for dissolution of the species retained on the filter were investigated. The detection limits were varying 0.06 gl − 1 for Cu to 2.5 gl − 1 for Cr. An application of the proposed method for analyte ions in mineral and tap water samples was also described with satisfactory results (recoveries 95%, relative standard deviations 10%). © 2002 Elsevier Science B.V. All rights reserved.