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Elena I. Morosanova - One of the best experts on this subject based on the ideXlab platform.
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Determination of Food Oxalates Using Silica–Titania Xerogel Modified with Eriochrome Cyanine R
MDPI AG, 2018Co-Authors: Maria A Morosanova, Zahar V. Samodelov, Elena I. MorosanovaAbstract:The interaction of silica–titania xerogel with triphenylmethane dyes (pyrocatechol violet, chrome azurol S, eriochrome cyanine R) has been investigated to create a new Sensor Material for solid phase spectrophotometric determination of food oxalates. The complex forming reaction between xerogel incorporated titanium(IV) and triphenylmethane dyes has been studied; half-reaction periods, complex composition, equilibrium constants, and xerogel sorption capacity have been calculated for each dye. Eriochrome cyanine R (ECR) is characterized by the shortest half-reaction period, the smallest equilibrium constant, and the greatest capacity; it has been chosen for the Sensor Material construction because titanium(IV)-ECR complex is formed faster and can be destroyed easier than other studied complexes. The interaction of this Sensor Material with oxalates has been described: the presence of oxalates causes Sensor Material discoloration and the absorbance is used as analytical signal. The analytical range is 35–900 mg/L (LOD 10.5 mg/L, n = 7). High concentrations of interfering inorganic anions, organic acids, and sucrose did not affect oxalate determination. Proposed solid phase spectrophotometric procedure has been successfully applied for the determination of oxalates in food samples (sorrel, spinach, parsley, ginger, and black pepper) and the results are in good agreement with HPLC oxalate determination
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Silica-titania xerogel doped with Mo,P-heteropoly compounds for solid phase spectrophotometric determination of ascorbic acid in fruit juices, pharmaceuticals, and synthetic urine
Chemistry Central Journal, 2017Co-Authors: Maria A Morosanova, Elena I. MorosanovaAbstract:Background Ascorbic acid is one of the most important vitamins to monitor in dietary sources (juices and vitamins) and biological liquids. Results Silica and silica-titania xerogels doped with Mo,P-heteropoly compounds (HPC) have been synthesized varying titanium(IV) and HPC content in sol. Their surface area and porosity have been studied with nitrogen adsorption and scanning electron microscopy, their elemental composition has been studied with energy-dispersive X-ray analysis. The redox properties of the Sensor Material with sufficient porosity and maximal HPC content have been studied with potentiometry and solid phase spectrophotometry and it has been used for solid phase spectrophotometric determination of ascorbic acid. The proposed method is characterized by good selectivity, simple probe pretreatment and broad analytical range (2–200 mg/L, LOD 0.7 mg/L) and has been applied to the analysis of fruit juices, vitamin tablets, and synthetic urine. Conclusions New Sensor Material has been used for simple and selective solid phase spectrophotometric procedure of ascorbic acid determination in fruit juices, vitamin tablets, and synthetic urine. Graphical abstract We synthesized several silica-titania xerogels doped with Mo,P-heteropoly compounds, studied their properties, and designed the Sensor Material for solid phase spectrophotometric determination of ascorbic acid in fruit juices, pharmaceuticals, and synthetic urine.
Young-geun Kim - One of the best experts on this subject based on the ideXlab platform.
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Corrosion behaviors of sputter-deposited steel thin film for electrical resistance Sensor Material
Surface & Coatings Technology, 2006Co-Authors: Young-geun Kim, Sungwon Jung, Seong Min Lee, Jiyoung Kim, Young Tai KhoAbstract:This paper describes an experimental approach for the study of electrochemical characteristics of the steel thin film with a thickness of 600 nm as an electrical resistance Sensor Material with an improved sensitivity for the corrosion rate measurement. The thin film was deposited onto the glass by magnetron-sputtering using carbon steel targets in an Ar atmosphere. The physical properties of fabricated thin films were investigated by the X-ray diffraction (XRD) analysis, adhesion test and Auger electron spectroscopy (AES). To ensure that the thin film could replicate the corrosion behavior of a bulk steel, the electrochemical polarization tests were performed. It was revealed that the adhesion strength and the electrochemical behaviors of thin films were comparable to those of the bulk steel by controlling the oxygen level in the films during the deposition process. A sensitive thin film electrical resistance (TFER) Sensor could be fabricated with this film and the enhanced sensitivity enables quick measurement of the corrosion rate. The TFER Sensor with the multiple-line pattern showed the enhanced sensitivity to localized corrosion phenomena. It was demonstrated that this method could be a reliable tool for corrosion monitoring.
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Corrosion properties of sputter-deposited steel thin film for electrical resistance Sensor Material
Electrochemistry Communications, 2006Co-Authors: Sungwon Jung, Young-geun KimAbstract:Steel thin films for an electrical resistance Sensor were prepared by sputter deposition. It was revealed that the electrochemical properties of the thin films were influenced by the surface roughness. Using an Al2O3 substrate with high surface roughness, it was possible to obtain a steel thin film with corrosion characteristics similar to bulk steel. The corrosion rate of the thin film was fairly well matched with bulk steel, enough to use as a Sensor Material. The fabricated thin film electrical resistance Sensor had a high enough sensitivity to detect a corrosion rate of 0.01 mm/y or less. Moreover, a specially designed multiple-line electrical resistance Sensor could successfully discriminate the localized pitting-type corrosion.
Maria A Morosanova - One of the best experts on this subject based on the ideXlab platform.
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Determination of Food Oxalates Using Silica–Titania Xerogel Modified with Eriochrome Cyanine R
MDPI AG, 2018Co-Authors: Maria A Morosanova, Zahar V. Samodelov, Elena I. MorosanovaAbstract:The interaction of silica–titania xerogel with triphenylmethane dyes (pyrocatechol violet, chrome azurol S, eriochrome cyanine R) has been investigated to create a new Sensor Material for solid phase spectrophotometric determination of food oxalates. The complex forming reaction between xerogel incorporated titanium(IV) and triphenylmethane dyes has been studied; half-reaction periods, complex composition, equilibrium constants, and xerogel sorption capacity have been calculated for each dye. Eriochrome cyanine R (ECR) is characterized by the shortest half-reaction period, the smallest equilibrium constant, and the greatest capacity; it has been chosen for the Sensor Material construction because titanium(IV)-ECR complex is formed faster and can be destroyed easier than other studied complexes. The interaction of this Sensor Material with oxalates has been described: the presence of oxalates causes Sensor Material discoloration and the absorbance is used as analytical signal. The analytical range is 35–900 mg/L (LOD 10.5 mg/L, n = 7). High concentrations of interfering inorganic anions, organic acids, and sucrose did not affect oxalate determination. Proposed solid phase spectrophotometric procedure has been successfully applied for the determination of oxalates in food samples (sorrel, spinach, parsley, ginger, and black pepper) and the results are in good agreement with HPLC oxalate determination
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Silica-titania xerogel doped with Mo,P-heteropoly compounds for solid phase spectrophotometric determination of ascorbic acid in fruit juices, pharmaceuticals, and synthetic urine
Chemistry Central Journal, 2017Co-Authors: Maria A Morosanova, Elena I. MorosanovaAbstract:Background Ascorbic acid is one of the most important vitamins to monitor in dietary sources (juices and vitamins) and biological liquids. Results Silica and silica-titania xerogels doped with Mo,P-heteropoly compounds (HPC) have been synthesized varying titanium(IV) and HPC content in sol. Their surface area and porosity have been studied with nitrogen adsorption and scanning electron microscopy, their elemental composition has been studied with energy-dispersive X-ray analysis. The redox properties of the Sensor Material with sufficient porosity and maximal HPC content have been studied with potentiometry and solid phase spectrophotometry and it has been used for solid phase spectrophotometric determination of ascorbic acid. The proposed method is characterized by good selectivity, simple probe pretreatment and broad analytical range (2–200 mg/L, LOD 0.7 mg/L) and has been applied to the analysis of fruit juices, vitamin tablets, and synthetic urine. Conclusions New Sensor Material has been used for simple and selective solid phase spectrophotometric procedure of ascorbic acid determination in fruit juices, vitamin tablets, and synthetic urine. Graphical abstract We synthesized several silica-titania xerogels doped with Mo,P-heteropoly compounds, studied their properties, and designed the Sensor Material for solid phase spectrophotometric determination of ascorbic acid in fruit juices, pharmaceuticals, and synthetic urine.
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a silica titania Sensor Material prepared by cetylpyridinium chloride assisted sol gel synthesis for solid phase spectrophotometric and visual test determination of propyl gallate in food samples
Analytical Methods, 2016Co-Authors: Maria A Morosanova, E I MorosanovaAbstract:A silica–titania xerogel obtained by cetylpyridinium chloride (CPC) assisted synthesis has been used as a new Sensor Material for solid phase spectrophotometric and visual test determination of propyl gallate. The increase in CPC concentration (from 0 to 2.4 × 10−4 mol L−1) in sol during the sol–gel process has led to the increase of the BET surface area (from 453 to 703 m2 g−1) and average pore diameter (from 18.5 to 25.6 A) of the dry xerogels. The interaction of these xerogels with propyl gallate has been investigated and the reaction conditions have been chosen. The fastest reaction of xerogel incorporated titanium(IV) with propyl gallate and the greatest equilibrium constant of this complex forming reaction have been observed for the xerogel with the maximal BET surface and pore diameter. This xerogel has been selected for solid phase spectrophotometric determination of propyl gallate (analytical range 2.0 × 10−7 mol L−1 to 4.0 × 10−6 mol L−1, LOD 7.1 × 10−8 mol L−1) and visual test determination in the range of 5.0 × 10−5 mol L−1 to 1.0 × 10−3 mol L−1. The parameters of test determination are: positive predictive value 89.5%, negative predictive value 95.0%, and reliability 92.3%. Both spectrophotometric and visual test procedures have been successfully applied to the analysis of refined vegetable oils and cookies.
Sungwon Jung - One of the best experts on this subject based on the ideXlab platform.
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Corrosion behaviors of sputter-deposited steel thin film for electrical resistance Sensor Material
Surface & Coatings Technology, 2006Co-Authors: Young-geun Kim, Sungwon Jung, Seong Min Lee, Jiyoung Kim, Young Tai KhoAbstract:This paper describes an experimental approach for the study of electrochemical characteristics of the steel thin film with a thickness of 600 nm as an electrical resistance Sensor Material with an improved sensitivity for the corrosion rate measurement. The thin film was deposited onto the glass by magnetron-sputtering using carbon steel targets in an Ar atmosphere. The physical properties of fabricated thin films were investigated by the X-ray diffraction (XRD) analysis, adhesion test and Auger electron spectroscopy (AES). To ensure that the thin film could replicate the corrosion behavior of a bulk steel, the electrochemical polarization tests were performed. It was revealed that the adhesion strength and the electrochemical behaviors of thin films were comparable to those of the bulk steel by controlling the oxygen level in the films during the deposition process. A sensitive thin film electrical resistance (TFER) Sensor could be fabricated with this film and the enhanced sensitivity enables quick measurement of the corrosion rate. The TFER Sensor with the multiple-line pattern showed the enhanced sensitivity to localized corrosion phenomena. It was demonstrated that this method could be a reliable tool for corrosion monitoring.
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Corrosion properties of sputter-deposited steel thin film for electrical resistance Sensor Material
Electrochemistry Communications, 2006Co-Authors: Sungwon Jung, Young-geun KimAbstract:Steel thin films for an electrical resistance Sensor were prepared by sputter deposition. It was revealed that the electrochemical properties of the thin films were influenced by the surface roughness. Using an Al2O3 substrate with high surface roughness, it was possible to obtain a steel thin film with corrosion characteristics similar to bulk steel. The corrosion rate of the thin film was fairly well matched with bulk steel, enough to use as a Sensor Material. The fabricated thin film electrical resistance Sensor had a high enough sensitivity to detect a corrosion rate of 0.01 mm/y or less. Moreover, a specially designed multiple-line electrical resistance Sensor could successfully discriminate the localized pitting-type corrosion.
Shaojun Dong - One of the best experts on this subject based on the ideXlab platform.
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bifunctional nanostructure of magnetic core luminescent shell and its application as solid state electrochemiluminescence Sensor Material
Journal of Physical Chemistry B, 2007Co-Authors: Lihua Zhang, Baifeng Liu, Shaojun DongAbstract:Bifunctional nanoarchitecture has been developed by combining the magnetic iron oxide and the luminescent Ru(bpy)32+ encapsulated in silica. First, the iron oxide nanoparticles were synthesized and coated with silica, which was used to isolate the magnetic nanoparticles from the outer-shell encapsulated Ru(bpy)32+ to prevent luminescence quenching. Then onto this core an outer shell of silica containing encapsulated Ru(bpy)32+ was grown through the Stober method. Highly luminescent Ru(bpy)32+ serves as a luminescent marker, while magnetic Fe3O4 nanoparticles allow external manipulation by a magnetic field. Since Ru(bpy)32+ is a typical electrochemiluminescence (ECL) reagent and it could still maintain such property when encapsulated in the bifunctional nanoparticle, we explored the feasibility of applying the as-prepared nanostructure to fabricating an ECL Sensor; such method is simple and effective. We applied the prepared ECL Sensor not only to the typical Ru(bpy)32+ co-reactant tripropylamine (TPA), bu...
