Preparación y caracterización de películas fotoluminiscentes de PVA dopadas con complejos metal-orgánicos de Eu3+

Roberto Garcia-Rosales; María del Rosario Ruiz-Guerrero; Aristeo Garrido-Hernández

doi:10.29057/icbi.v9iespecial2.8022

Preparación y caracterización de películas fotoluminiscentes de PVA dopadas con complejos metal-orgánicos de Eu3+

PÄDI Boletín Científico de Ciencias Básicas e Ingenierías del ICBI ◽

10.29057/icbi.v9iespecial2.8022 ◽

2021 ◽

Vol 9 (Especial2) ◽

pp. 123-127

Author(s):

Roberto Garcia-Rosales ◽

María del Rosario Ruiz-Guerrero ◽

Aristeo Garrido-Hernández

Keyword(s):

Tape Casting ◽

Ft Ir

El presente trabajo se centra en la caracterización de una matriz polimérica de alcohol polivinílico (PVA), preparada a partir de la dispersión de un complejo mononuclear organometálico a base de europio trivalente, Eu3+. Los complejos de Eu3+ se sintetizaron previamente en medio acuoso a condiciones ambientales empleando aniones benzoato como ligandos orgánicos, que sigue a la formula Eu(OOCC6H5)3· (H2O)3 (Para fines prácticos la identificaremos como EuL3. Una vez caracterizado el complejo obtenido en forma de polvo, se dispersó mediante ultrasonido en la matriz de PVA. Se prepararon y caracterizaron películas con diferentes proporciones molares del complejo en relación con el polímero huésped. Las películas de 0.5 mm de espesor fueron obtenidas mediante la técnica “Tape-casting“. Las caracterizaciones que se realizaron mediante la técnica FT-IR y espectroscopia de fluorescencia. La matriz de PVA genera una sensibilización en la excitación del complejo EuL3 presentando un desplazamiento en el espectro de excitación de 288 a 280 nm; además, se observó un aumento en la emisión luminiscente debido a procesos de transferencia de energía intra o intermolecular de la matriz hacia los núcleos activos de europio.

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Effect of fabrication technique on the crystalline phase and electrical properties of PVDF films

Materials Science-Poland ◽

10.1515/msp-2015-0020 ◽

2015 ◽

Vol 33 (1) ◽

pp. 157-162 ◽

Cited By ~ 12

Author(s):

P. K. Mahato ◽

A. Seal ◽

S. Garain ◽

S. Sen

Keyword(s):

Polyvinylidene Fluoride ◽

Tape Casting ◽

Dimethyl Formamide ◽

Pvdf Film ◽

X Ray Diffraction ◽

Β Phase ◽

Cast Films ◽

Solvent Cast ◽

Ft Ir ◽

Ferroelectric Hysteresis

AbstractThe effect of different fabrication techniques on the formation of electroactive β-phase polyvinylidene fluoride (PVDF) has been investigated. Films with varying concentration of PVDF and solvent - dimethyl formamide (DMF) were synthesized by tape casting and solvent casting techniques. The piezoelectric β-phase as well as non polar β-phase were observed for both the tape cast and solvent cast films from X-ray diffraction (XRD) micrographs and Fourier transform infra-red spectroscopy (FT-IR) spectra. A maximum percentage (80 %) of β-phase was obtained from FT-IR analysis for a solvent cast PVDF film. The surface morphology of the PVDF films was analyzed by FESEM imaging. The dielectric properties as a function of temperature and frequency and the ferroelectric hysteresis loop as a function of voltage were measured. An enhancement in the value of the dielectric constant and polarization was obtained in solvent cast films.

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Adhesive Selection for Lamellar Composites Alumina/Kevlar® for Impact Absorption

Materials Science Forum ◽

10.4028/www.scientific.net/msf.881.277 ◽

2016 ◽

Vol 881 ◽

pp. 277-282

Author(s):

Natália Maria de Faria ◽

Rosa Maria Rocha ◽

Cristina Moniz Araujo Lopes

Keyword(s):

High Speed ◽

Low Cost ◽

Tape Casting ◽

Peel Test ◽

Casting Process ◽

Thin Plates ◽

Polymeric Fibers ◽

New Approach ◽

High Speed Impact ◽

Ft Ir

Alumina has been applied in systems of protection against high speed impact due mostly to the mechanical properties, low cost and ease of processing. A new approach to this application involves the manufacture of lamellar bioinspired composites of thin plates of alumina obtained by tape casting process, and fabrics of poly (p-aramid), Kevlar ®. The aim of this study is to investigate the interaction between the ceramic and polymeric fibers fabric observing the influence of different nature adhesives to select the most suitable for further preparation of bioinspired lamellar composite for impact protection applications. The strength of adhesion is evaluated by 90° Degree Peel Test and the interaction is investigated using techniques of optical microscopy, scanning electron microscopy (SEM) and spectroscopy with Fourier transform infrared (FT-IR) to characterize the surfaces of substrates after testing. Polyurethane aqueous based adhesive presented better interaction with both materials when compared to organic solvent based adhesive.

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Preparation and Visible-Light Photocatalytic Activity of Cu2O/PVA/Chitosan Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.623 ◽

2014 ◽

Vol 1015 ◽

pp. 623-626 ◽

Cited By ~ 3

Author(s):

Chun Hua Cao ◽

Ling Xiao

Keyword(s):

Visible Light ◽

Tape Casting ◽

Composite Films ◽

Casting Process ◽

Precipitation Method ◽

Blend Films ◽

Decolorization Rate ◽

Ft Ir ◽

Chitosan Composite ◽

Visible Light Photocatalytic

Cu2O/PVA/chitosan composite films were prepared successfully by reduction-precipitation method and tape casting process. The composite films were characterized by TEM, SEM, XRD and FT-IR. The characterization results showed that Cu2O particles were 200-300 nm in diameter and in situ formed on PVA-chitosan blend films. The visible-light photocatalytic decolorization behavior on Cu2O/PVA/chitosan was evaluated using reactive brilliant red X-3B (X-3B) as a model pollutant. The influences of various experimental factors on X-3B decolorization were investigated. Results showed that the decolorization rate of X-3B could reach 99.8% after 50 min irradiation under the conditions of initial dye concentration 20 mg/L, catalyst amount of 0.8 g/L, H2O2 dosage of 4.04 mmol/L and pH 5.6. After composite film was reused for 5 times, the decolorization rate of X-3B could still reach more than 90% after 110 min irradiation

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FT-IR microspectroscopic analysis of diseased white matter brain tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141214 ◽

1995 ◽

Vol 53 ◽

pp. 968-969

Author(s):

Steven M. Le Vine ◽

David L. Wetzel

Keyword(s):

White Matter ◽

Gray Matter ◽

Twitcher Mouse ◽

Grid Pattern ◽

Marked Contrast ◽

Spatially Resolved ◽

Ft Ir ◽

Ir Microspectroscopy ◽

Chemical Evidence

In situ FT-IR microspectroscopy has allowed spatially resolved interrogation of different parts of brain tissue. In previous work the spectrrscopic features of normal barin tissue were characterized. The white matter, gray matter and basal ganglia were mapped from appropriate peak area measurements from spectra obtained in a grid pattern. Bands prevalent in white matter were mostly associated with the lipid. These included 2927 and 1469 cm-1 due to CH2 as well as carbonyl at 1740 cm-1. Also 1235 and 1085 cm-1 due to phospholipid and galactocerebroside, respectively (Figs 1and2). Localized chemical changes in the white matter as a result of white matter diseases have been studied. This involved the documentation of localized chemical evidence of demyelination in shiverer mice in which the spectra of white matter lacked the marked contrast between it and gray matter exhibited in the white matter of normal mice (Fig. 3).The twitcher mouse, a model of Krabbe’s desease, was also studied. The purpose in this case was to look for a localized build-up of psychosine in the white matter caused by deficiencies in the enzyme responsible for its breakdown under normal conditions.

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Ultra-spatially resolved synchrotron powered FT-IR microspectroscopy of individual cells of biological material

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140798 ◽

1995 ◽

Vol 53 ◽

pp. 884-885

Author(s):

David L. Wetzel ◽

John A. Reffner ◽

Gwyn P. Williams

Keyword(s):

Thermal Noise ◽

Spot Size ◽

Acquisition Time ◽

Thermal Source ◽

Signal To Noise ◽

Spatially Resolved ◽

Good Spatial Resolution ◽

Small Spot ◽

Ft Ir ◽

Ir Microspectroscopy

Synchrotron radiation is 100 to 1000 times brighter than a thermal source such as a globar. It is not accompanied with thermal noise and it is highly directional and nondivergent. For these reasons, it is well suited for ultra-spatially resolved FT-IR microspectroscopy. In efforts to attain good spatial resolution in FT-IR microspectroscopy with a thermal source, a considerable fraction of the infrared beam focused onto the specimen is lost when projected remote apertures are used to achieve a small spot size. This is the case because of divergence in the beam from that source. Also the brightness is limited and it is necessary to compromise on the signal-to-noise or to expect a long acquisition time from coadding many scans. A synchrotron powered FT-IR Microspectrometer does not suffer from this effect. Since most of the unaperatured beam’s energy makes it through even a 12 × 12 μm aperture, that is a starting place for aperture dimension reduction.

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FR-IR Molecular Microanalysis System

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134958 ◽

1990 ◽

Vol 48 (2) ◽

pp. 270-271

Author(s):

John A. Reffner ◽

William T. Wihlborg

Keyword(s):

Fourier Transform ◽

Fourier Transform Infrared ◽

Integrated System ◽

Morphological Examination ◽

Fully Integrated ◽

Ir Microscopy ◽

Normal Functions ◽

Infrared Microspectroscopy ◽

Infrared Spectral ◽

Ft Ir

The IRμs™ is the first fully integrated system for Fourier transform infrared (FT-IR) microscopy. FT-IR microscopy combines light microscopy for morphological examination with infrared spectroscopy for chemical identification of microscopic samples or domains. Because the IRμs system is a new tool for molecular microanalysis, its optical, mechanical and system design are described to illustrate the state of development of molecular microanalysis. Applications of infrared microspectroscopy are reviewed by Messerschmidt and Harthcock.Infrared spectral analysis of microscopic samples is not a new idea, it dates back to 1949, with the first commercial instrument being offered by Perkin-Elmer Co. Inc. in 1953. These early efforts showed promise but failed the test of practically. It was not until the advances in computer science were applied did infrared microspectroscopy emerge as a useful technique. Microscopes designed as accessories for Fourier transform infrared spectrometers have been commercially available since 1983. These accessory microscopes provide the best means for analytical spectroscopists to analyze microscopic samples, while not interfering with the FT-IR spectrometer’s normal functions.

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Polarized microbeam FT-IR analysis of single fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163496 ◽

1996 ◽

Vol 54 ◽

pp. 206-207

Author(s):

Liling Cho ◽

David L. Wetzel

Keyword(s):

Molecular Orientation ◽

Transition Point ◽

Polymer Fibers ◽

Single Fiber ◽

Wire Grid ◽

Polyester Fibers ◽

Ft Ir ◽

Ir Analysis ◽

The Relationship ◽

Wire Grid Polarizer

Polarized infrared microscopy has been used for forensic purposes to differentiate among polymer fibers. Dichroism can be used to compare and discriminate between different polyester fibers, including those composed of polyethylene terephthalate that are frequently encountered during criminal casework. In the fiber manufacturering process, fibers are drawn to develop molecular orientation and crystallinity. Macromolecular chains are oriented with respect to the long axis of the fiber. It is desirable to determine the relationship between the molecular orientation and stretching properties. This is particularly useful on a single fiber basis. Polarized spectroscopic differences observed from a single fiber are proposed to reveal the extent of molecular orientation within that single fiber. In the work presented, we compared the dichroic ratio between unstretched and stretched polyester fibers, and the transition point between the two forms of the same fiber. These techniques were applied to different polyester fibers. A fiber stretching device was fabricated for use on the instrument (IRμs, Spectra-Tech) stage. Tension was applied with a micrometer screw until a “neck” was produced in the stretched fiber. Spectra were obtained from an area of 24×48 μm. A wire-grid polarizer was used between the source and the sample.

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Chromatography and Modification of Nucleosides - Analytical Methods for Major and Modified Nucleosides: HPLC, GC, MS, NMR, UV and FT-IR

10.1016/s0301-4770(08)x6066-x ◽

1990 ◽

Keyword(s):

Analytical Methods ◽

Modified Nucleosides ◽

Ft Ir

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Pemanfaatan Cangkang Pensi (Corbicula Moltkiana) sebagai Bahan Penyerap Zat Warna Rhodamin B Dalam Larutan

Talenta Conference Series Science and Technology (ST) ◽

10.32734/st.v2i2.500 ◽

2019 ◽

Vol 2 (2) ◽

Author(s):

Rahmiana Zein ◽

Mutia Khuratul Aini ◽

Hermansyah Aziz

Keyword(s):

Rhodamine B ◽

Sem Analysis ◽

Spectra Analysis ◽

Biosorption Capacity ◽

Biosorption Process ◽

Langmuir Isotherm Model ◽

Ft Ir ◽

Cationic Exchange ◽

Rhodamin B ◽

Model Isotherm

Biosorpsi zat warna Rhodamine B menggunakan cangkang Pensi (Corbicula moltkiana) telah dikaji. Percobaan dilakukan dengan system batch guna memperoleh kondisi optimum biosorspi zat warna. Kapasitas biosorpsi zat warna pada pH 2 adalah 0.9958 mg/g, dengan konsentrasi larutan mula-mula 150 mg/L waktu kontak 105 menit, massa biosorben 0.1 g, ukuran partikel 32 µm dan temperature pengeringan biosorben pada 75oC. Model isotherm Langmuir menunjukkan bahwa proses penyerapan berlangsung secara kimia dan biosorpsi homogeny dari adsorbat (Rhodamine B) pada permukaan biosorben membentuk lapisan tunggal dengan nilai R2 0.9966. Analisis XRF menunjukkan bahwa penurunan kadar unsur logam pada cangkang Pensi membuktikan bahwa proses biosorpsi berlangsung dengan pertukaran kation. Hasil analisis spektrum FT-IR membuktikan adanya interaksi antaramolekul Rhodamin B dengan gugus fungsi pada cangkang Pensi. Analisis dengan SEM memperlihatkan bahwa pori-pori cangkang Pensi telah terisi penuh oleh molekul Rhodamin B. Kondisi optimum biosorpsi telah diaplikasikan pada limbah kerupuk merah dengan kapasitas penyerapan sebesar 0,2835 mg/g. The biosorption of Rhodamine B dyes by Pensi (Corbicula moltkiana) shell has been investigated. The experiment was conducted in batch sistem in order to obtain the optimum conditions of dye biosorption. Biosorption capacity of dye was 0.9958 mg/g at pH 2, initial concentration 150 mg/L, contact time 105 minutes, biosorbent mass 0.1 gram, particle size 32 µ m and biosorbent drying temperature was at 75oC. The Langmuir Isotherm model showed chemisorption and homogeneous biosorption process of adsorbates onto the biosorbent surface formed monolayer dye molecules on the biosorbent surface with R2 value was 0.9966. XRF analysis showed that reduction of metals unsure quantity of pensi shell indicated biosorption process was occupied through cationic exchange. The result of FTIR spectra analysis indicated an interaction between Rhodamin B molecules and functional group of pensi shell. SEM analysis showed that the pensi shell pores were completely filled by Rhodamine B molecules. The optimum condition of biosorption has been aplicated in red chips wastewater industry with biosorption capacity was 0.2835 mg/g.

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