scholarly journals In Situ FT-IR and Raman Spectroscopies for Electrochemical Interfaces

Hyomen Kagaku ◽  
2006 ◽  
Vol 27 (10) ◽  
pp. 591-594
Author(s):  
Takashi ITOH
Keyword(s):  
Ir And Raman Spectroscopies ◽  
Ft Ir ◽  
Electrochemical Interfaces ◽  
Ir And Raman

scholarly journals Synthesis of Poly(methacrylic acid-co-butyl acrylate) Grafted onto Functionalized Carbon Nanotube Nanocomposites for Drug Delivery

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 533 ◽  
Author(s):  
Josué A. Torres-Ávalos ◽  
Leonardo R. Cajero-Zul ◽  
Milton Vázquez-Lepe ◽  
Fernando A. López-Dellamary ◽  
Antonio Martínez-Richa ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Drug Delivery ◽  
Methacrylic Acid ◽  
Butyl Acrylate ◽  
Chemical Vapor ◽  
Vis Spectroscopy ◽  
Ir And Raman Spectroscopies ◽  
Ft Ir

Design of a smart drug delivery system is a topic of current interest. Under this perspective, polymer nanocomposites (PNs) of butyl acrylate (BA), methacrylic acid (MAA), and functionalized carbon nanotubes (CNTsf) were synthesized by in situ emulsion polymerization (IEP). Carbon nanotubes were synthesized by chemical vapor deposition (CVD) and purified with steam. Purified CNTs were analyzed by FE-SEM and HR-TEM. CNTsf contain acyl chloride groups attached to their surface. Purified and functionalized CNTs were studied by FT-IR and Raman spectroscopies. The synthesized nanocomposites were studied by XPS, 13C-NMR, and DSC. Anhydride groups link CNTsf to MAA–BA polymeric chains. The potentiality of the prepared nanocomposites, and of their pure polymer matrices to deliver hydrocortisone, was evaluated in vitro by UV–VIS spectroscopy. The relationship between the chemical structure of the synthesized nanocomposites, or their pure polymeric matrices, and their ability to release hydrocortisone was studied by FT-IR spectroscopy. The hydrocortisone release profile of some of the studied nanocomposites is driven by a change in the inter-associated to self-associated hydrogen bonds balance. The CNTsf used to prepare the studied nanocomposites act as hydrocortisone reservoirs.

scholarly journals Sonochemical-assisted magnesium borate synthesis from different boron sources

2017 ◽  
Vol 19 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Meral Yildirim ◽  
Azmi Seyhun Kipcak ◽  
Emek Moroydor Derun
Keyword(s):  
High Efficiency ◽  
Synthesis Method ◽  
Spectroscopic Studies ◽  
X Ray Diffraction ◽  
Magnesium Borate ◽  
Ir And Raman Spectroscopies ◽  
Ft Ir ◽  
Surface Morphologies ◽  
Ir And Raman ◽  
Good Agreement

Abstract In this study, sonochemical-assisted magnesium borate synthesis is studied from different boron sources. Various reaction parameters are successfully applied by a simple and green method. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Raman spectroscopies are used to characterize the synthesized magnesium borates on the other hand surface morphologies are investigated by using scanning electron microscope (SEM). The XRD analyses showed that the products were admontite [MgO(B2O3)3 · 7(H2O)] with JCPDS (Joint Committee on Powder Diffraction Standards) no. of 01-076-0540 and mcallisterite [Mg2(B6O7(OH)6)2 · 9(H2O)] with JCPDS no. of 01-070-1902. The results that found in the spectroscopic studies were in a good agreement with characteristic magnesium borate bands in both regions of infra-red and visible. According to SEM results, obtained borates were in micro and sub-micro scales. By the use of ultrasonication, reaction yields were found between 84.2 and 97.9%. As a result, it is concluded that the sonochemical approach is a practicable synthesis method to get high efficiency and high crystallinity in the synthesis magnesium borate compounds.

In situ Spectroelectrochemical Study of the Anodic Dissolution of Silicon by Potential-Difference and Electromodulated FT-IR Spectroscopy

1997 ◽  
Vol 51 (4) ◽  
pp. 519-525 ◽  
Author(s):  
F. Ozanam ◽  
C. Da Fonseca ◽  
A. Venkateswara Rao ◽  
J.-N. Chazalviel
Keyword(s):  
Infrared Spectroscopy ◽  
Anodic Dissolution ◽  
Potential Difference ◽  
Free Carrier Absorption ◽  
Rate Limiting Step ◽  
Microscopic Models ◽  
Carrier Absorption ◽  
Ft Ir ◽  
Electrochemical Interfaces

The anodic dissolution of p-Si has been investigated by in situ infrared spectroscopy. The combination of potential-difference and electromodulated spectroscopies allows for the acquisition of a rather complete picture of the various regimes of the dissolution. After a review of general principles for studying electrochemical interfaces, a study of the interfacial oxide layer formed in the electropolishing regime is presented. Quantitative analysis shows that the thickness and quality of the oxide (density and defect content) depend upon electrode potential. Free-carrier absorption detected in electromodulated spectra shows that the blocking character of the oxide is correlated with the buildup of a stoichiometric oxide of low defectivity at sufficiently positive potentials. Furthermore, the dynamic response to the modulation reveals that oxides formed at weak positive potentials interact with electrolyte species through electro-induced adsorptions/desorptions on charged SiOH sites. At more positive potentials, charge is transported across the oxide by charged defects which could be associated with tricoordinated, positively charged SiO species. Finally, results obtained during porous silicon formation at weak positive potentials are presented. Potential-difference spectroscopy indicates that the electrode exhibits a very large specific surface area, and that the surface is covered by SiH bonds. Electromodulated infrared spectroscopy reveals that the SiH species are generated upon anodic current flowing and that the breaking of these bonds is the rate-limiting step of the anodic reaction. These unexpected results have given rise to the elaboration of new microscopic models for the direct anodic dissolution of silicon in fluoride electrolytes.

scholarly journals The FT-IR and Raman Spectroscopies as Tools for Biofilm Characterization Created by Cariogenic Streptococci

2020 ◽  
Vol 21 (11) ◽  
pp. 3811 ◽  
Author(s):  
Barbara Gieroba ◽  
Mikolaj Krysa ◽  
Kinga Wojtowicz ◽  
Adrian Wiater ◽  
Małgorzata Pleszczyńska ◽  
...  
Keyword(s):  
Extracellular Polymeric Substances ◽  
Inorganic Ions ◽  
Bacterial Biofilm ◽  
Tooth Decay ◽  
Bacterial Proteins ◽  
Product Characterization ◽  
Complex Microbial Community ◽  
Ir And Raman Spectroscopies ◽  
Ft Ir ◽  
Ir And Raman

Fourier transform infrared (FT-IR) and Raman spectroscopy and mapping were applied to the analysis of biofilms produced by bacteria of the genus Streptococcus. Bacterial biofilm, also called dental plaque, is the main cause of periodontal disease and tooth decay. It consists of a complex microbial community embedded in an extracellular matrix composed of highly hydrated extracellular polymeric substances and is a combination of salivary and bacterial proteins, lipids, polysaccharides, nucleic acids, and inorganic ions. This study confirms the value of Raman and FT-IR spectroscopies in biology, medicine, and pharmacy as effective tools for bacterial product characterization.

scholarly journals Mechanical Properties and Weathering Behavior of Polypropylene-Hemp Shives Composites

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Marcel Ionel Popa ◽  
Silvia Pernevan ◽  
Cecilia Sirghie ◽  
Iuliana Spiridon ◽  
Dorina Chambre ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Degradation ◽  
Accelerated Weathering ◽  
Ir And Raman Spectroscopies ◽  
Before And After ◽  
Ft Ir ◽  
Main Components ◽  
Poly Propylene ◽  
Ir And Raman

This paper presents the obtaining and the characterization of composites with polypropylene matrix and hemp shives as filler in different ratios and containing poly(propylene)-co maleic anhydride (MAH-PP) 3% wt as compatibility agent. The weathering behavior of the composite enclosing 60% hemp shives, performed after the exposure to UV radiations at different exposure times, was evaluated. The changes in the chemical and morphological structures were investigated by FT-IR and RAMAN spectroscopies and AFM microscopy. The mechanical characteristics of the composites were determined before and after an artificial aging process, and they are within the limits of the values reported for polyolefin-based composites and materials with natural fillers. During the accelerated weathering process, the correlation between the chemical degradation of the main components of the composite and the modification of the mechanical properties after the process of aging has been observed.

FT-IR AND RAMAN SPECTROSCOPIC STUDIES OF xAg2O · (100 - x)[B2O3 · As2O3] GLASS SYSTEM

2010 ◽  
Vol 24 (01) ◽  
pp. 51-58 ◽  
Author(s):  
S. C. BAIDOC ◽  
I. ARDELEAN
Keyword(s):  
Ir Spectroscopy ◽  
Structural Changes ◽  
Spectroscopic Studies ◽  
Glass System ◽  
Structural Units ◽  
Raman Spectroscopic ◽  
Ir And Raman Spectroscopies ◽  
Ft Ir ◽  
Ir And Raman ◽  
Ft Ir Spectroscopy

Structural analysis of x Ag 2 O · (100-x)[ B 2 O 3 · As 2 O 3] glass system, with 0 ≤ x ≤ 10 mol%, was performed by means of FT-IR and Raman spectroscopies. The purpose of this work is to investigate the structural changes that appear in the B 2 O 3 · As 2 O 3 glass matrix with the addition and increase of silver ion content. Boroxol rings, pyro-, ortho-, di-, tri-, tetra- and penta-borate groups, structural units characteristic to As 2 O 3 were found in the structure of the studied glasses. FT-IR spectroscopy measurements show that BO 3 units are the main structural units of the glass system. The presence of structural units characteristic to Ag 2 O were not directly evidenced by FT-IR spectroscopy. The Raman analysis leads to similar conclusions as the FT-IR measurements.

scholarly journals Synthesis and Impedance Spectroscopy of Poly(p-phenylenediamine)/Montmorillonite Composites

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3132
Author(s):  
Udit Acharya ◽  
Patrycja Bober ◽  
Muhammed Arshad Thottappali ◽  
Zuzana Morávková ◽  
Magdalena Konefał ◽  
...  
Keyword(s):  
Impedance Spectroscopy ◽  
Transport Mechanism ◽  
Oxidative Polymerization ◽  
Charge Transport Mechanism ◽  
X Ray ◽  
Ammonium Peroxydisulfate ◽  
Ir And Raman Spectroscopies ◽  
Temperature Ranges ◽  
Ft Ir ◽  
Ir And Raman

Poly(p-phenylenediamine)/montmorillonite (PPDA/MMT) composites were prepared by the oxidative polymerization of monomers intercalated within the MMT gallery, using ammonium peroxydisulfate as an oxidant. The intercalation process was evidenced by X-ray powder diffraction. The FT-IR and Raman spectroscopies revealed that, depending on the initial ratio between monomers and MMT in the polymerization mixture, the polymer or mainly oligomers are created during polymerization. The DC conductivity of composites was found to be higher than the conductivity of pristine polymer, reaching the highest value of 10−6 S cm−1 for the optimal MMT amount used during polymerization. Impedance spectroscopy was performed over wide frequency and temperature ranges to study the charge transport mechanism. The data analyzed in the framework of conductivity formalism suggest different conduction mechanisms for high and low temperature regions.

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