FTIR spectroscopy Research Papers - Academia.edu (original) (raw)

This article reports the results of an investigation into the efficiency of mechanical activation to increase the reactivity in alkali activated mortar synthesized from low-grade clay. Mechanical activation significantly changed the structure of clay, increasing the specific surface area, and decreasing the particle size. The 7-day compressive strength of mortar synthesized from untreated clay was 31.7 MPa, which increased to 35.3 after 4 h milling. A further increase of grinding time to 8 h did not result in any increase in compressive strength which is attributed to a decrease in the workability. However, the extent of reactivity did significantly increase as determined from solid-state MAS NMR, FTIR, and EDS analyses. Solid-state MAS NMR results revealed the increased formation of Q 4 (2Al) silicon sites, which is correlated with improved reaction. Furthermore, the EDS and FTIR analysis results indicated greater incorporation of aluminium into the matrix structure with increased grinding time.

- by
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- Materials Science, FTIR spectroscopy, Solid State NMR, CT scanning

Single crystals of L-Tartaric acid (C 4 H 6 O 6), an organic nonlinear optical (NLO) material, have been grown by hanging seed solution and submerged seed solution techniques at room temperature. The crystal system has been confirmed from the single crystal X-ray diffraction analysis. The crystalline perfection was evaluated using high-resolution X-ray diffractometry (HRXRD). From this analysis, it was found that the quality of the crystal is quite good. The functional groups were identified using FTIR spectroscopy. UV-vis-NIR spectrum showed the absence of absorption in the wavelength region of 220-900 nm. The second harmonic generation efficiency is 89% compared to that of standard potassium dihydrogen phosphate (KDP). The laser damage threshold value is much higher than that of KDP and closer to that of b-barium borate.

- by Gajanan Muley
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- Crystal Growth, Nonlinear Optics, FTIR spectroscopy, Second Harmonic Generation

SpecTRoScopy for Grape and Wine Analysis F TIR spectroscopy is a nondestructive technique that provides structural information on molecular features of a large range of compounds. Its main advantages are speed, a high degree of automation, medium resolution, and cost-effectiveness. Recent improvements in instrumentation together with advances in fiber optics and chemometrics have provided an analytical tool that is suitable for routine qualitative analysis and process control in many industries. Although FTIR spectroscopy is widely applied in the food industry, acceptance of this technology in the grape and wine industry has been relatively slow and mainly FTIR spectroscopy can assist the highly diversified and tradition-bound wine industry in meeting product and quality control challenges.

- by Kim Esbensen
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- Chemical Engineering, Analytical Chemistry, FTIR spectroscopy, Analytical

In the field of FTIR spectroscopy, the far infrared (FIR) spectral region has been so far less investigated than the mid-infrared (MIR), even though it presents great advantages in the characterization of those inorganic compounds, which are inactive in the MIR, such as some art pigments, corrosion products, etc. Furthermore, FIR spectroscopy is complementary to Raman spectroscopy if the fluorescence effects caused by the latter analytical technique are considered. In this paper, ATR in the FIR region is proposed as an alternative method to transmission for the analyses of pigments. This methodology was selected in order to reduce the sample amount needed for analysis, which is a must when examining cultural heritage materials. A selection of pigments have been analyzed in both ATR and transmission mode, and the resulting spectra were compared with each other. To better perform this comparison, an evaluation of the possible effect induced by the thermal treatment needed for the preparation of the polyethylene pellets on the transmission spectra of the samples has been carried out. Therefore, pigments have been analyzed in ATR mode before and after heating them at the same temperature employed for the polyethylene pellet preparation. The results showed that while the heating treatment causes only small changes in the intensity of some bands, the ATR spectra were characterized by differences in both intensity and band shifts towards lower frequencies if compared with those recorded in transmission mode. All pigments' transmission and ATR spectra are presented and discussed, and the ATR method was validated on a real case study.

- by SILVIA PRATI
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- Engineering, Cultural Heritage, FTIR spectroscopy, Raman Spectroscopy

The preparation and characterization of Langmulr-Blodgett (LB) films of mesoporphyrin IX dimethylester indium chloride are reported. The utility of complementary experimental techniques such as electron diffraction, polarized visible spectroscopy and cyclic voltammetry in yielding information about molecular orientatton and interactions is highlighted. Our results are consistent w~th verhcal packing of the porphyrin ring on the aqueous subphase and transfer of the material in a similar orientation onto a number of different substrates. From polarized UV-visible spectroscopic measurements an average tilt angle 0 between molecular planes and substrate of 64 ° _+ 15 ° is calculated. An area per molecule on the subphase and m the LB films of 0.55 nm 2 ts obtained from pressure-area curves and coulometrtc measurements respectively. A high degree of crystallimty in the layers is apparent from selected area electron diffraction patterns and the films degrade rapidly on exposure to the electron beam. There is considerable interaction between molecules m the films and this leads to peak broadening in both visible absorption spectra and cyclic voltammograms. An underpotential of 700 mV for the reduction of the porphyrin is consistent with surface potential measurements reported earlier.

- by Pilar Cea
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- Engineering, Materials Engineering, Condensed Matter Physics, Chemistry

Two paintings, made on aluminium support by Silvio Pasotti (one belonging to a private Italian collection, a larger one to the civic collections of the City of Segrate, Milan, Italy) were investigated in a totally non-invasive manner to identify the materials used by the artist.
Pasotti belongs to the major exponents of 1960s Italian pop art, together with Valerio Adami, Emilio Tadini, Lucio del Pezzo, and the so called "artists of Piazza del Popolo": Mario Schifano, Tano Festa, Franco Angeli, Mimmo Rotella, Giosetta Fioroni, Mario Ceroli, Cesare Tacchi, Renato Mambor.
Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), visible reflectance spectroscopy, and spectrofluorimetry with visible excitation were exploited as molecular analysis techniques, which are particularly suitable to recognise also synthetic organic materials, such as pigments and binders. The effectiveness of this multi-analytical approach was demonstrated, leading to the identification of several synthetic organic pigments, both conventional and “special effect” ones, introduced during the first half of the 20th century, as well as some well-established inorganic ones. Combining FTIR results both in the medium and near IR ranges, considerations regarding the binders employed by the artist could also be made, suggesting the use of both nitrocellulose and acrylic paints.
Imaging techniques, such as IR reflectography, false colour IR, UV induced fluorescence, and portable microscopy, were also used to achieve a better knowledge of the painting practice.

- by Gianluca Poldi and +1
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- Contemporary Art, FTIR spectroscopy, Raman Spectroscopy, Vibrational Spectroscopy
- by Lingfen Rao
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- Data Analysis, FTIR spectroscopy, Chemical Analysis, Coordination number

Processible nanocomposites of carboxyl functionalized conducting polymer "polyanthranilic acid" (PANA) with multiwalled carbon nanotubes (MWNTs) are prepared using two different synthesis routes viz. single phase and two phase polymerization. The novel nanocomposite materials are characterized using X-ray diffraction (XRD), thermogravimetric (TGA), electrochemical impedance (EI), scanning electron microscope (SEM) and high resolution transmission electron microscope (HRTEM) techniques for their structural, thermal, electrochemical and surface morphological properties. SEM and HRTEM images are confirmed that nanotubes are dispersed uniformly in polymer matrix and polymer chains wrap around the nanotubes walls. The interaction between MWNTs and PANA is analyzed by Raman and Fourier transform infrared (FTIR) spectroscopy. UV-vis spectroscopic technique is used to obtain the optical bandgap of nanocomposites. PANA-MWNTs nanocomposites are used for the first time for fabrication of sandwich type devices with a configuration of metal Al/PANA-MWNTs nanocomposite/indium tin oxide coated glass (ITO). The current density-voltage (J-V) and capacitance-voltage (C-V) characteristics of the Schottky diode are subsequently used for extracting electronic parameters of the devices. These measurements revealed that the junction electrical parameters depend strongly on the synthesis route for preparation of nanocomposites.

- by Arun Kumar Singh
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- Materials Engineering, Condensed Matter Physics, FTIR spectroscopy, Morphology

Crystals of LTA zeolites were obtained in absence of organic templates using a crystallization temperature of 373 K. The as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-Transform Infrared (FTIR) spectroscopy. The aging time was found to be a crucial factor for the control of the crystal size. Samples aged between 72 and 144 h presented an

- by salvador alfaro
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- Engineering, Crystal Growth, FTIR spectroscopy, Scanning Electron Microscopy

The crystallization of complex phosphates from the melts of Cs 2 O-P 2 O 5-CaO-M III 2 O 3 (M III-Al, Fe, Cr) systems have been investigated at fixed value Cs/P molar ratios equal to 0.7, 1.0 and 1.3 and Ca/P ¼ 0.2 and Ca/M III ¼1. The fields of crystallization of CsCaP 3 O 9 , b-Ca 2 P 2 O 7 , Cs 2 CaP 2 O 7 , Cs 3 CaFe(P 2 O 7) 2 , Ca 9 M III (PO 4) 7 (M III-Fe, Cr), Cs 0.63 Ca 9.63 Fe 0.37 (PO 4) 7 and CsCa 10 (PO 4) 7 were determined. Obtained phosphates were investigated using powder X-ray diffraction and FTIR spectroscopy. Novel whitlockite-related phases CsCa 10 (PO 4) 7 and Cs 0.63 Ca 9.63 Fe 0.37 (PO 4) 7 have been characterized by single crystal X-ray diffraction: space group R3c, a ¼10.5536(5) and 10.5221(4)Å, c ¼37.2283(19) and 37.2405(17)Å, respectively.

- by Ivan Ogorodnyk
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- Materials Science, Inorganic Chemistry, FTIR spectroscopy, Solid State Chemistry

The interaction of CO with two aerogel solids have been investigated by in situ FTIR spectroscopy in order to obtain experimental data on the mechanism of formation of the formate species which can be considered as the intermediate adsorbed species in the methanol synthesis from CO/H 2. The adsorption of CO on ZrO 2 and ZnO/ZrO 2 aerogel solids was studied in the temperature range 298±623 K. At temperatures lower than 373 K, CO is mainly reversibly adsorbed on a cationic site M 1 , leading to an IR band at 2192 cm À1 on ZrO 2 and 2183 cm À1 on ZnO/ZrO 2. It is shown that this adsorption follows the Langmuir's model on both solids. At higher temperatures (T>400 K) formate species are detected characterized on ZrO 2 by IR bands at 2967, 2882, 1576 1382 and 1367 cm À1. It is shown that the formation of this species: (a) decreases the number of cationic sites M 1 which adsorb CO at temperatures lower than 373 K and (b) creates a new cationic site M 2. This is interpreted by a mechanism of formation of the formate species involving two sites of the surface: an OH group and a cationic site M 1. The CO is ®rst adsorbed on the cationic site M 1 , followed by a reaction with an OH group to produce a formate species. This last species is adsorbed on the cationic site M 1 and a new cationic site M 2 is formed.

- by Tarik Chafik
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- Engineering, FTIR spectroscopy, CHEMICAL SCIENCES

The synthesis of AB 2 -type miktoarm star polymers using a combination of reversible addition-fragmentation chain transfer (RAFT), ring opening polymerization (ROP) and ''Click'' chemistry was demonstrated in this work. An azide functional RAFT agent was used to polymerize butyl acrylate, polyethylene glycol acrylate and N-isopropylacrylamide monomers. Propargylamine was reacted with glycerine carbonate to obtain a dihydroxy functional alkyne compound which was used for the ring opening polymerization of 3-caprolactone (3-CL) and lactide. The resulting alkyne functional polycaprolactone (PCL) and polylactide (PLA) polymers were reacted with azide functional polymers in the presence of copper bromide (CuBr) catalyst to obtain miktoarm star polymers. The polymers were characterized by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. The star polymers had low polydispersity (w1.3) with well-defined structures. These polymers have a number of potential applications including crosslinking agents for polyurethane (PU) coatings for biodegradable and fouling release applications.

- by kunal singh
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- Engineering, Nuclear Magnetic Resonance, FTIR spectroscopy, NMR Spectroscopy

The formation of sodium carboxymethyl cellulose (SCMC) based semi-interpenetrating networks (semi-IPN) with poly(acylamide-co-2-acrylamido-2-methy-l-propanesulfonic-acid) hydrogels. The hydrogels were prepared by free-radical polymerization using redox initiator. The characterizations of hydrogels were done by swelling experiments, FTIR spectroscopy and DSC analysis. Morphology of the samples were examined by SEM. Experimental results indicate that the semi-IPN hydrogel containing 0.10 g of SCMC and 5.829 mM of AMPS, shows the highest swelling capacity (64.83 g/g). The swelling behavior of the semi-IPN hydrogel (AS5) was studied in different pH solutions. The ranitidine hydrochloride drug loading and release of the semi-IPN hydrogels were studied by using a UV spectrophotometer.

- by Kokkarachedu Varaprasad
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- FTIR spectroscopy, Drug Release, Carboxymethyl cellulose

The thick film NixZn(1−x)Fe2O4 on alumina substrate was prepared by screen printing of the ferrite powder synthesized by chemical co-precipitation method using nitrate precursors. These NixZn(1−x)Fe2O4 thick films of varying x were characterized by X-ray diffraction, FTIR spectroscopy and SEM (scanning electron microscopy). The permittivity and permeability were measured by overlay technique. Voltage standing wave ratio method was also used to measure the dielectric constant. The permittivity was found to increase with Ni content varying between 13 and 18. The permeability was ∼3.01. The overlay technique provides an easy method for measurement of permittivity and permeability of ferrite thick film.

Synthetic saponite-like materials were prepared by traditional hydrothermal crystallisation at 513 K of 1 SiO 2 ; 0.835MgO; 0.056Al 2 O 3 ; 0.056Na 2 O; nH 2 O gel with variable amount of H 2 O. The obtained layered materials were submitted to a systematic study of textural properties, morphology, thermal behaviour of the produced materials by combining different experimental techniques (XRD, SEM, TEM, N 2 physisorption, Solid State MAS NMR). For the first time, a fine characterisation of the surface acidity of the produced saponites performed by FTIR spectroscopy of CO probe molecule (complemented with NH 3 ) was given.

- by Leonardo Marchese and +1
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- Engineering, Materials Engineering, Mechanical Engineering, Chemical Engineering

On Earth, the Dry Valleys of Antarctica provide the closest martian-like environment for the study of extremophiles. Colonies of bacteries are protected from the freezing temperatures, the drought and UV light. They represent almost half... more

- by Stéphane Dumas and +1
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- Astrobiology, FTIR spectroscopy

This study focused on the characterization of fouling cake layer during operation of a membrane bioreactor system employed for the treatment of synthetic hypersaline oily wastewater. Also the effects of ultrasound and addition of four types of flocculants (aluminium sulfate, Chitosan, ferric chloride, polyaluminium chloride) on mitigation of membrane fouling were studied. The components of the foulants were examined by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray (EDX) analysis, inductively coupled plasma (ICP) and particle size analyzer (PSA). The FTIR demonstrated that membrane fouling layer is governed by the deposition of organic and inorganic substances composed of extracellular polymeric substances (EPS) (proteins, polysaccharides, etc.), hydrocarbon components and inorganic matters. The AFM images of the fouled membrane confirmed the idea of surface coverage as a fouling mechanism. The SEM analysis showed that rod-shape bacterial clusters were one of the contributors to membrane cake layer. The EDX and ICP results showed that Mg, Al, Ca, Na, K and Fe were the major metal elements in the fouling cake. The PSA results indicate that membrane foulants had a much smaller size than mixed liquor suspensions in the MSBR. Fouling mitigation experiments showed that the effect of organic flocculant was more than inorganic chemicals but the overall effects were not significant. Ultrasound could effectively remove the fouling cake from the membrane surface and thus recovered the membrane permeation flux for a long time.

Polymeric films can be grown by a sequential, self-limiting surface chemistry process known as molecular layer deposition (MLD). The MLD reactants are typically bifunctional monomers for stepwise condensation polymerization and can yield completely organic films. The MLD of organic-inorganic hybrid polymers can also be accomplished using a bifunctional organic monomer and a multifunctional inorganic monomer. In this work, the growth of a poly(aluminum ethylene glycol) polymer is demonstrated using the sequential exposures of trimethylaluminum (TMA) and ethylene glycol (EG). These hybrid polymers, known as alucones, were grown over a wide range of temperatures from 85 to 175°C. In situ quartz crystal microbalance and ex situ X-ray reflectivity experiments confirmed linear growth of the alucone film versus number of TMA/EG reaction cycles at all temperatures. The alucone growth rates decreased at higher temperatures. Growth rates varied from 4.0 Å per cycle at 85°C to 0.4 Å per cycle at 175°C. In situ Fourier transform infrared spectroscopy was used to monitor the surface reactions during alucone MLD. Ex situ FTIR spectroscopy, X-ray photoelectron spectroscopy, and X-ray reflectivity measurements were also employed to determine the chemical composition, thickness, and density of the alucone films. These ex situ studies revealed that the alucone films grown on Al 2 O 3 ALD surfaces evolved under ambient conditions before reaching a stable state. Alucone films capped with rapid SiO 2 ALD displayed much more stability than alucone films grown on Al 2 O 3 ALD surfaces. These results indicated that H 2 O may facilitate the chemical transformation of the alucone MLD films. The alucone films represent a new class of organic-inorganic hybrid polymers. Modification of this basic alucone MLD chemistry with use of other diols or other bifunctional monomers can produce different alucone polymers with variable properties.

- by Jacob Bertrand
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- Engineering, Materials Science, Chemistry, Materials Chemistry

Upon the removal of water, proteins undergo a major, reversible rearrangement of their secondary structure, as revealed by FTIR spectroscopy. We have found herein that for recombinant human albumin (rHA) the extent of this structural change does not depend significantly either on the composition of the aqueous solution prior to lyophilization (protein concentration, pH, and the presence of excipients such as dextran or NaCI) or on the mode of dehydration (lyophilization, spray drying, or rotary evaporation), even though these factors profoundly affect rHA's solid-state stability against moisture-induced aggregation. In all cases, the a-helix content of rHA drops from 58% in solution to 25-35% in the dehydrated state, the /3-sheet content rises from 0 to 10-20%, and unordered structures increase from 40% to 50-60%. We have also investigated another model protein, hen egg-white lysozyme, and confirmed that it too undergoes a significant alteration of the secondary structure upon lyophilization. The extent of this structural reorganization has been found to be insensitive to the pH of the aqueous solution prior to lyophilization from pH 1.9 to 5.1, even though the thermal transition temperature (T m) in aqueous solution over this range varies by 30°C.

- by Prashant Mishra
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- Water, Protein Folding, FTIR spectroscopy, Protein Stability

Fourier transform infrared (ITIR) spectroscopic measurements, performed in the far-IR region (200400 cm-') on binary coprecipitated Ni(II)-Fe(II1) hydroxides (20-60 at.% Fe/(Ni + Fe)), are presented and discussed. Heating the sample containing 60 at.% Fe to 6OO"C, monitored by differential scanning calorimetry (DSC) measurements, results in the formation of a nickel ferrite structure from its precursor present in binary hydroxides. The role of Fe-to-Ni ratio non-uniformities within the surface and bulk of the binary hydroxide crystallites, as revealed by Miissbauer measurements, Auger electron spectroscopy and depth profiling performed previously, is also discussed with regard to the formation of a-Fe20j and NiO impurities on thermal treatment. 0 1997 Elsevier Science B.V.

- by Mira Ristić
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- Physical Chemistry, FTIR spectroscopy, Differential scanning calorimetry, Nickel

Poultry feed lipid n − 3 n − 6 fatty acids n − 6:n − 3 ratio FTIR spectroscopy Partial least squares a b s t r a c t A rapid, simple and reproducible single bounce attenuated total reflectance (SB-ATR) Fourier transform infrared (FTIR) spectroscopic method was developed for determination of the n − 6, n − 3 and ratio of n − 6:n − 3 polyunsaturated fatty acids (PUFAs) in poultry feed lipids using partial least squares (PLS) regression. Data for n − 6, n − 3 and ratio of n − 6:n − 3 was acquired by gas chromatography (GC) and used as a standard values for FTIR calibration. The best regression results were achieved using first derivatives of the 1475-650 cm −1 spectral region for n − 6, n − 3 and ratio of n − 6:n − 3 with high regression coefficients (R 2 ) of 0.999, 0.994 and 0.998, respectively and low RMSEP values of 1, 0.06 and 0.83, respectively. The results of the present study revealed that FTIR could be used for rapid and accurate determination of n − 6, n − 3 and ratio of n − 6:n − 3 PUFAs present in poultry feed lipids.

- by Abdul Rauf Khaskheli
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- FTIR spectroscopy, Vibrational Spectroscopy, Gas Chromatography, Fatty Acid

BSb films were deposited onto fused silica substrates by coevaporating B and Sb from appropriate boats. Optical studies indicated an indirect band gap of $0.59 eV. The films thus prepared were characterized by measuring X-ray diffraction... more

BSb films were deposited onto fused silica substrates by coevaporating B and Sb from appropriate boats. Optical studies indicated an indirect band gap of 0.59eV.ThefilmsthuspreparedwerecharacterizedbymeasuringX−raydiffraction(XRD),Fouriertransforminfrared(FTIR)spectroscopy,scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),andX−rayphotoelectronspectroscopy(XPS)studies.XPSstudiesindicatedtheratioofB:Sb0.59 eV. The films thus prepared were characterized by measuring X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) studies. XPS studies indicated the ratio of B:Sb 0.59eV.ThefilmsthuspreparedwerecharacterizedbymeasuringX−raydiffraction(XRD),Fouriertransforminfrared(FTIR)spectroscopy,scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),andX−rayphotoelectronspectroscopy(XPS)studies.XPSstudiesindicatedtheratioofB:Sb1. XRD indicated the reflections from (1 0 1), (1 1 1), (1 1 2), (3 3 0), (3 3 1) and (3 2 3) planes of zinc blende BSb. FTIR spectra indicated the peaks for B-B, B-O, B-Sb vibration modes. A strong peak located at $151 cm À1 for B-Sb modes dominated the Raman spectra. Electrical resistivity was measured for B-Sb films in the temperature range of 100-353 K. Electron transport process was seen to be governed by Mott's hopping when complete temperature dependence of the conductivity is considered. r

Melanin is of interest as a model system of understanding disorder in biological systems. The biological functionality of melanin depends on disorder which is considered as its essential part. This property distinguishes melanin from other much more intensively studied biomolecule systems such as nucleic acid, proteins and carbohydrates. Melanins have been reported to have a diverse number of functions in the biosystem, including photosensitization, metal ion chelation, photoprotection to absorb a broad range of electromagnetic radiation, antibiotic, thermoregulation. Melanins are found all over the body from the skin and blood to the nervous system but the role of melanin in all these system is unclear. FTIR spectroscopy technique is usually one of the most preferred techniques used to give a correct assignment of the observed spectral characteristic of functional groups corresponding to different absorption bands which are responsible of the absorption. FTIR is the characterization technique which is both rapid, non-destructive and requires small sized samples. In the material to be analysed, chemical bonds vibrate at a characteristic frequency representative of their structure, bond angle and length. FTIR spectrometer is important for the interpretation of the structure, binding capacity, affinity and sites of metal ions in melanin. These are important factors for better understanding the metals melanin complexity and its consequences. The analysis of sepia melanin by FTIR reveals that there is existence of functional groups that can be responsible for the binding cites of different metallic ions leading to many new applications of sepia melanin.

- by Agnes Mbonyiryivuze
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- Spectroscopy, FTIR spectroscopy

Considerable controversy exists concerning the rate of coal pyrolysis. At 800°C the reported rates derived using a single first-order process to define weight loss vary from < 1 s-1 to ~100 s- 1. In an attempt to resolve this controversy, a new pyrolysis experiment has been designed which allows direct measurement of coal temperature and reaction time. It uses a small-diameter electrically heated tube into which coal and helium are injected. The reaction distance is varied by moving the electrode positions. Temperature is measured inside and outside the tube with a thermocouple. Temperatures of the solids are determined at the tube exit using FT-i.r. emission and transmission spectroscopy. The transit time for a pulse of coal is measured using phototransistors at the top and bottom of the tube. Particle velocities are also determined using FT-IR transmission. Measurements have been made on sieved size fractions of a North Dakota lignite, Rosebud subbituminous coal and Illinois No. 6 bituminous coal in tubes up to 240 cm long at asymptotic tube temperatures of 600, 700, 800 and 935°C. At 800°C primary pyrolysis was completed in a period of 14 ms, during which the maximum coal temperature was increasing from 600 to 740°C. The results are in good agreement with a previously developed functional-group model of coal pyrolysis which employs a distribution of activation energies to describe the evolution of individual pyrolysis species. The results are also in reasonable agreement with predictions of a single first-order model for weight loss which uses a rate constant k=4.28 x 1O4 exp(-228500/RT) Jmol-’ s-1. This rate,which is over 1000 s-l at 800°C, is inconsistent with the low rates. Reasons for discrepancies in reported rates are discussed

- by Michael A Serio
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- Kinetics, FTIR spectroscopy, Pyrolysis, Kinetics of Pyrolysis of Coals
- by M. Ziolek
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- Engineering, Chemistry, FTIR spectroscopy, DFT calculation

Two novel zeolites MCM-58 and MCM-68 with 12-ring channels and containing the cages in the structure were investigated with respect to their acidic properties and compared with other two 12-ring zeolites, namely Beta and ZSM-12. The main objective was to characterize the accessibility and acid strength of Lewis and Brønsted sites using FTIR spectroscopy. Pyridine adsorption allowed for quantification of Brønsted and Lewis acid centres and pointed out that while in the structure of MCM-58 nearly all Al atoms form acidic SiAOHAAl bridges, only about half of Al is a source of the Brønsted acidity in MCM-68. The special attention was devoted to the origin and location of the hydrogen-bonded OH groups in the MCM-58 zeolite. The frequency lowering is caused by the across-the-ring interaction with the oxygen atom and not by the interaction with the nearby OH groups, as proved by high temperature activation and deuteration experiments. The location of the 3485 cm À1 OH groups in the five member ring was proposed. Carbon monoxide adsorption allowed proposing the location of the residual K + cations in the main channels of MCM-58 and in the 6 10 4 6 cages in MCM-68.

- by Barbara Gil
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- Engineering, Chemistry, Structure, FTIR spectroscopy

Global food shortage is mainly due to the post-harvest spoilage of food, rather than its under-production, especially in the sub-Saharan African countries. Rapid detection tools for the spoilage of fruit such as banana (Musa acuminata) would be a great resource in alleviating losses during post-harvest storage. In this study, silver-based colloidal nanoparticle (AgNPs) solution was synthesized using culture supernatant or wet biomass (cell pellets) of Bacillus subtilis. The synthesized silver nanoparticles solution was confirmed using UV-Vis Spectrophotometer and further characterized using Scanning Electron Microscope (SEM), X-ray Diffractometer (XRD) and Fourier Transmission Infrared (FT-IR), and then evaluated as a colorimetric sensor for the volatile compound released during the deterioration of Musa acuminata. The original reddish brown colour of the silver nanoparticle solution changed to light brown by the end of the fourth day and finally turned transparent on the tenth day. Simultaneous analysis carried out by UV-Vis spectroscopy corroborates our investigation of AgNPs as a colorimetric sensor displaying selectivity and specificity for 1,2-Benzenedicarboxylic acid, bis (2-methyl propyl) ester which was released during the deterioration of Musa acuminata. The use of colorimetric sensor as conducted in this study will help in easy detection for control of crop deterioration.

- by Richard K Omole
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- Synthesis of nanoparticles, Biotechnology, FTIR spectroscopy, Nanotechnology

The drug-excipients compatibility study is the preliminary step in the development of solid
dosage form of a drug substances and it is defined as an investigation of physico chemical
propertiesof drug substance alone and when combined with excipients. The drug-excipients
compatibility study in physical mixture techniques were employed.Paracetamol(N-acetyl-paminopheno)
is a commonly used analgesic and antipyretic drug, present indifferent
pharmaceutical formulationsthis combination has demonstrated genuine synergy in animal
studies and also combines withparacetamol’s rapid onset of efficacy with Tramadol’s
prolonged analgesic effect.The efficacy and tolerability of Paracetamol plus Tramadol in both
acute and chronic pain.DSC and FTIR provides important data on the evaluation of stability
of a pharmaceutical formulation.The present work will help in the development of recent type
of dosages forms (immediate release, extentded release, effervescent tablets etc.) of
Paracetamol with Tramadol combination. Paracetamol due to its impurity p-amino phenol
having genotoxic potential therefore it is very essential to study its compatibility with other
drugs and excipient used in combination with Paracetamol. Thus the main aim of my present
work is to determine the compatibility of Paracetamol with Tramadol and several excipients
for quality control and routine analysis of these drugs in their marketed formulation. Result of
DSC comparison of thermal curve of pure substances with the curve obtained from 1:1
physical mixture of Paracetamol and Tramadol and adequate excipient with suitable
compatibility.and result of FTIR combination of Paracetamol and Tramadol showed
coressesponding peaks for various bond present in structure and not change in functional
groups. And excipent showed minute (HPMC, LACTOSE) change in vibrational frequencies
for their corresponding various bond .

- by Karan Gupta
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- FTIR spectroscopy, Differential Scanning Calorimetry (DSC)

Sulfate–zirconia catalysts were prepared via the colloidal-sol–gel method using ZrOCl2as precursor. After precipitation and washing, the solids were peptized with a 1 : 1 mixture of CH3COOH and H2SO4. The promoters were introduced as gallium, indium, or thallium nitrates into the solution containing the zirconium sols. After a gel formation period, the samples were dried and calcined. The catalysts were

- by Simona Coman
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- Chemical Engineering, Catalysis, FTIR spectroscopy, Heterogeneous Catalysis

each case, side chain alterations of solvent-exposed tyrosine, aspartate, and glutamate residues were observed. For the cytochrome c 552 ± talc complex, these changes are followed by a slow refolding of the peptide chain in the binding... more

- by Tewfik Soulimane
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- FTIR spectroscopy, Adsorption, Bentonite, Structural Change

Chemical characteristics of wood are used in this study for plant taxonomy classification based on the current Angiosperm Phylogeny Group classification (APG III System) for the division, class and subclass of woody plants. Infrared spectra contain information about the molecular structure and intermolecular interactions among the components in wood but the understanding of this information requires multivariate techniques for the analysis of highly dense datasets. This article is written with the purposes of specifying the chemical differences among taxonomic groups, and predicting the taxa of unknown samples with a mathematical model. Principal component analysis, t-test, stepwise discriminant analysis and linear discriminant analysis, were some of the chosen multivariate techniques. A procedure to determine the division, class, subclass, order and family of unknown samples was built with promising implications for future applications of Fourier Transform Infrared spectroscopy in wood taxonomy classification

- by Jose Gonzalez-Rodriguez
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- Botany, Forensic Science, Chemometrics, FTIR spectroscopy

Single crystal and powder X-ray diffraction (XRD) Crystal structure determination FTIR spectroscopy Differential scanning calorimetry (DSC) Simultaneous TG/DTA Binary melting phase diagrams Eutectic compositions and temperatures Structure-property relationship a b s t r a c t A novel co-crystal of trans-(R,R)-1,2-cyclohexanediol and (R,R)-tartaric acid (with 1:1 molar ratio, 1) has been found to be a key crystalline compound in the improved resolution of (±)-trans-1,2-cyclohexanediol by supercritical fluid extraction. The molecular and crystal structure of this co-crystal, which crystallizes in orthorhombic crystal system (space group P2 1 2 1 2 1 , a = 6.7033(13) Å, b = 7.2643(16), c = 24.863(5), Z = 4), has been solved by single crystal X-ray diffraction (R = 0.064). The packing arrangement consists of two dimensional layers of sandwich-like sheets, where the inner part is constructed by double layers of tartaric acids which hydrophilicity is "covered" on both upper and bottom side by cyclohexanediols with the hydrophobic cyclohexane rings pointing outward. Thus, a rather complex hydrogen bonding pattern is constructed. The relatively high melting point (133 • C) observed by both simultaneous TG/DTA and DSC, and the main features of FTIR-spectrum of 1 are explained by the increased stability of this crystal structure. DSC studies on binary mixtures of co-crystal 1 with (R,R)-1,2-cyclohexanediol or (R,R)-tartaric acid, revealed eutectic temperatures of T eu = 100 or 131 • C, respectively. Between (S,S)-1,2-cyclohexanediol and (R,R)-tartaric acid a eutectic temperature of T eu = 85 • C have also been observed. The phase relations have been confirmed by powder X-ray diffraction, as well.

- by László Párkányi and +1
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- Analytical Chemistry, FTIR spectroscopy, Crystal structure, Differential scanning calorimetry

Material identification of historical objects has a great importance for better understanding and reproduction process of ancient arts as a basic prior to applying the appropriate conservation method. In this research an inscription related to Ansarin house of Tabriz was studied. It has used in open air space under environmental factors which has caused to structural and visual decays. The aim of the study was identification of pigments and ink of script and ornaments by application chemical spot tests, polarized light microscopy, SEM-EDX and FTIR spectrometry. Results have indicated the use of carbon ink in inscription and ultramarine blue (Lapis lazuli), white lead, red lead (minium), massicot (litharge) with chalk as filler and copper alloys as golden pigment. Corrosion products of copper alloys such as carboxylates, appears as a green layer on golden areas.

- by Ali Nemati Babaylou
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- FTIR spectroscopy, Pigments, Persian Calligraphy

Synthesis of nanoparticles of Ni-Zn ferrite dispersed in aniline formaldehyde copolymer using a room temperature route and the effect 57ö f heat treatment on these samples were studied using XRD, FTIR spectroscopy, Fe Mossbauer spectroscopy and TEM microscopy. The results show the formation of nanosized particles of Ni-Zn ferrite in the polymer matrix at room temperature. On pyrolysis, the Ni-Zn ferrite phase persists up to 500 8C. However, heating of composites to 700 8C results in the partial reduction of the spinel ferrite leading to the formation of Ni-Fe alloy under ambient conditions and complete reduction of the alloy on heating in inert atmosphere.

Organometallic-cyclodextrin inclusion compounds were obtained by the treatment of molybdenocene dichloride (Cp 2 MoCl 2 ) with the modified cyclodextrins (CDs) heptakis-2,3,6-tri-O-methyl-b-CD (TRIMEB) and 2-hydroxypropyl-b-CD (HPbCD) in aqueous solution. The products were isolated by liophilisation and characterised in the solid-state by powder XRD, thermogravimetric analysis, Raman and FTIR spectroscopy, and 13 C CP MAS NMR spectroscopy. The results are consistent with inclusion of Cp 2 MoCl 2 , rather than hydrolysis products such as [Cp 2 Mo(H 2 O)X] + (X = Cl, OH) or [Cp 2 Mo(H 2 O) 2 ] 2+ . The pure non-included metallocene Cp 2 MoCl 2 and its inclusion compounds with unmodified b-CD, TRIMEB and HPbCD were screened for their potential antiproliferative and cytotoxic activity, in both human cancer and healthy cell lines. Inclusion in CD was found to enhance the cytotoxic effect of Cp 2 MoCl 2 , with the TRIMEB adduct displaying the highest anti-tumour activity, along with the lowest toxicity towards non-neoplastic cells.

- by Joana De Sousa and +1
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- Inorganic Chemistry, Organic Chemistry, FTIR spectroscopy, Organometallic Chemistry

The study of cremated human remains from archaeological contexts has traditionally been viewed as less valuable than the study of inhumed bodies. However, recent methodological and theoretical developments regarding the taphonomic processes that transform the human body during cremation have highlighted their potential for understanding past cultural and funerary practices. This study combines the first application of spectroscopic with more traditional methods of studying cremated bone to examine Romano-British contexts, with the aim of better understanding funerary practices along the military frontier. Five Romano-British military sites from northern England (Beckfoot, Carlisle, Herd Hill, Lincoln and Malton) were studied, with remains excavated from a range of cinerary urn contexts. Despite the known heterogeneity of the ethnic composition of the Roman army, analyses revealed a surprising consistency with respect to the cremation practice, implying shared knowledge of pyre procedure and, possibly, a prescribed funerary practice amongst military communities in the Roman North. The consistency within these five northern provincial sites in Britain stands in contrast to cremation contexts from Roman sites elsewhere in Europe, as well as other periods of the British past. The associated material culture recovered from these cremation deposits, however, does provide evidence for differences in dress and bodily display. This contrasts with the homogeneity of the cremation technology and highlights the importance of these individualizing features for signalling identity amongst Roman military communities in Britain.

- by Robert Witcher
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- FTIR spectroscopy, Funerary Archaeology, Taphonomy, Roman Britain

Analytic potentials are built for all four 2S+1Πu/g states of Li2 dissociating to Li(2S) + Li(3P): 3b(33Πu), 3B(31Πu), 3C(31Πg), and 3d(33Πg). These potentials include the effect of spin-orbit coupling for large internuclear distances, and include state of the art long-range constants. This is the first successful demonstration of fully analytic diatomic potentials that capture features that are usually considered too difficult to capture without a point-wise potential, such as multiple minima, and shelves. Vibrational energies for each potential are presented for the isotopologues 6,6Li2, 6,7Li2, 7,7Li2, and the elusive `halo nucleonic molecule' 11,11Li2. These energies are claimed to be accurate enough for new high-precision experimental setups such as the one presented in {[}Sebastian \emph{et al.} Phys. Rev. A, \textbf{90}, 033417 (2014){]} to measure and assign energy levels of these electronic states, all of which have not yet been explored in the long-range region. Measuring energies in the long-range region of these electronic states may be significant for studying the ab initio vs experiment discrepancy discussed in [Tang et al. Phys. Rev. A, 84, 052502 (2014)] for the C3 long-range constant of Lithium, which has significance for improving the SI definition of the second.

FTIR spectroscopic and texture analysis studies were undertaken to elucidate the molecular basis of structure-functionality relationships of porcine plasma proteins in solution and the gel state at varying pH. At room temperature, porcine plasma proteins aggregated as a function of decreasing pH. A parallel decrease in the intensity of amide I 0 bands at 1652 cm À1 in the infrared spectra of the protein solution (assigned to a-helix, predominant in serum albumin) and 1688/1638 cm À1 (assigned to intramolecular antiparallel b-sheet, predominant in immunoglobulins) along with an increase in the band at 1644 cm À1 (assigned to unordered or random structure) was observed to take place with decreasing pH. Bands assigned to intermolecular antiparallel b-sheet structures (1683 and 1617 cm À1 ) were observed in infrared spectra of porcine plasma protein solutions heated to the point of gel formation. Texture and water holding capacity were also very sensitive to pH. The results indicate that the lower the remaining native secondary structure and the faster the heat-induced aggregation (observed by FTIR spectroscopy) with decreasing pH, the weaker and more exudative the gels. r

- by Elena Saguer
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- FTIR spectroscopy, Texture Analysis, Secondary Structure, Room Temperature
- by Helena Pereira
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- FTIR spectroscopy, Wood, Infrared spectroscopy, Chemical Analysis

The photochemical stability and photodegradation pathways of poly(2,2,2-tri¯uoroethyl methacrylate) (PTFEMA) and copolymers of 1H,1H,2H,2H-per¯uorodecyl methacrylate with 2-ethylhexyl methacrylate (XFDMA±EHMA) have been investigated under arti®cial solar light irradiation. The extent of degradation was assessed by weight loss and gel content determination, size exclusion chromatography and FTIR spectroscopy. PTFEMA exposed up to 2000 h showed only molecular changes due to a low extent of chain scission. The two XFDMA±EHMA copolymers underwent much more degradation, with extensive cross-linking, formation of low-molecular weight products, and oxidation reactions on the chains. The behaviour of the copolymers is controlled by the reactivity of the EHMA units, as was shown by comparison with results obtained on degradation of PEHMA homopolymer. #

- by Oscar Chiantore
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- Engineering, Materials Engineering, Chemical Engineering, Analytical Chemistry

Optically transparent Al 2 O 3 films has been synthesized, on quartz substrates at 500, 600 and 700 • C, from 0.02 M aluminum acetyl acetonate (Al(acac) 3 ) in ethanol, by using ultrasonic spray pyrolysis technique. The films synthesized at 500, 600 and 700 • C are amorphous having average particle sizes 27 ± 6, 18 ± 3 and 14 ± 3, respectively. The films are found to be 95% optically transparent in the visible region. The optical transparency of the films in the ultraviolet region is found to increase with increase in deposition temperature. The observed increase in optical band gap and decrease in refractive index is attributed to the decrease in particle size with increase in deposition temperature. The stoichiometry and chemical bonding of the amorphous film studied using XPS and FTIR spectroscopy revealed the presence chemisorbed oxygen.

- by M Kamruddin
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- FTIR spectroscopy, Multidisciplinary, Ultraviolet, Thin Film

The microbial diversity of water kefir, made from a mixture of water, dried figs, a slice of lemon and sucrose was studied. The microbial consortia residing in the granules of three water kefirs of different origins were analyzed. A collection of 453 bacterial isolates was obtained on different selective/differential media. Bacterial isolates were grouped with randomly amplified polymorphic DNA (RAPD)-PCR analyses. One representative of each RAPD genotype was identified by comparative 16S rDNA gene sequencing. The predominant genus in water kefirs I and II was Lactobacillus, which accounted for 82.1% in water kefir I and 72.1% in water kefir II of the bacterial isolates. The most abundant species in water kefirs I and II were Lactobacillus hordei and Lb. nagelii followed by considerably lower numbers of Lb. casei. Other lactic acid bacteria (LAB) were identified as Leuconostoc mesenteroides and Lc. citreum in all three water kefirs. The most abundant species in water kefir III was Lc. mesenteroides (28%) and Lc. citreum (24.3%). A total of 57 LAB belonging to the species of Lb. casei, Lb. hordei, Lb. nagelii, Lb. hilgardii and Lc. mesenteroides were able to produce exopolysacchrides from sucrose. Non LABs were identified as Acetobacter fabarum and Ac. orientalis. The Acetobacter species were more prevalent in consortium III. Cluster analyses of RAPD-PCR patterns revealed an interspecies diversity among the Lactobacillus and Acetobacter strains. Aditionally, Saccharomyces cerevisiae, Lachancea fermentati, Hanseniaospora valbyensis and Zygotorulaspora florentina were isolated and identified by comparison of partial 26S rDNA sequences and FTIR spectroscopy.

- by Mareike Wenning
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- Microbiology, FTIR spectroscopy, Industrial Biotechnology, Microbial diversity

In this paper a synthetic chronological survey of analytical applications of infrared spectroscopy for the characterization of the materials of polychrome works of art and archaeology is outlined. Various sampling methods are described and some relevant examples, drawn from the published cases, are presented. The various methods prove to be very effective in characterizing both the inorganic and organic constituents of a wide variety of artworks, giving an insight into the materials and techniques of execution of the artifacts and, in the case of infrared mapping techniques, pinpointing the analytical data within a precise layer of the stratigraphy of the cross-sectioned samples. Overall, the great analytical potential and wide field of application of this technique is fully brought to light. © 2001 Éditions scientifiques et médicales Elsevier SAS polychrome works of art / cross-sections / FTIR spectroscopy / FTIR microspectroscopy / fiber optics reflection spectroscopy 2. Infrared spectroscopy and art conservation 2.1. The past: going from dispersive to Fourier transform instruments In 1966 a paper by J.S. Olin entitled 'The use of Infrared Spectrophotometry in the examination of *Correspondence and reprints.

- by Francesca Casadio
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- Archaeology, Cultural Heritage, FTIR spectroscopy, Sampling methods

Calcium dihydrogenphosphate monohydrate (Ca(H 2 PO 4) 2 •H 2 O) was prepared by a rapid and simple precipitation method using CaCO 3 and H 3 PO 4 in aqueous and acetone media at ambient temperature. The thermal transformation of the synthesized Ca(H 2 PO 4) 2 •H 2 O at 500 • C was obtained to be CaP 2 O 6 occurred through the dehydration and the phosphate condensation reactions, as revealed by thermoanalytical techniques (TG/DTG/DTA). The synthesized Ca(H 2 PO 4) 2 •H 2 O and its decomposition product CaP 2 O 6 were characterized by X-ray powder diffraction (XRD), Fourier transfer infrared (FTIR) spectroscopy and scanning electron microscope (SEM). Thermal behavior and the morphology of the synthesized Ca(H 2 PO 4) 2 •H 2 O in aqueous and acetone media are compared with those of other works. The SEM micrograph of Ca(H 2 PO 4) 2 •H 2 O show parallelogram-like microparticles containing small and large grain sizes. The aqueous and acetone media are proposed to play an important role in the synthetic process of calcium phosphates in exhibiting different physical properties, which are important for specific applications.

- by Banjong Boonchom
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- Materials Engineering, Condensed Matter Physics, Chemistry, Microstructure

Yttrium iron garnet (YIG) is a synthetic Ferrimagnetic material. YIG is cubic in structure; having space group Ia3d. In YIG, out of 5 Fe 3+ ions, 3 Fe ions occupy tetrahedral site and 2 Fe ions occupy octahedral site. Difference in the spin orientation of the Fe 3+ ions present in tetrahedral and octahedral sites results in the origin of the magnetic properties of YIG. Yttrium iron garnet with the empirical formula Y 3 Fe 5 O 12 has been synthesized by regular ceramic route and sintering at 1200˚C for 30 minutes using microwave furnace. The structural and morphological characterization of the synthesized YIG are performed by X-ray diffractometer (XRD), and scanning electron microscopy (SEM). X-ray diffraction pattern revealed pure YIG phase as reported by Musa et al [1]. The crystallite size from the Scherrer equation is found to be 2.82Å. A saturation magnetization of 16.88emu/g is achieved by VSM.

- by Abhijeet Nayak
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- Materials Science, Magnetic Materials, FTIR spectroscopy, Structural Analysis

The thermoxidative (oven ageing) and photooxidative degradation of polypropylene films (2OOpm thick) containing a range of antioxidants and light stabilisers, together with anatase and rutile titanium dioxide pigments are studied by Fourier Transform infra-red (FTIR) spectroscopy. Rates of thermal and photooxidative degradation are determined by measuring the formation of non-volatile carbonyl and hydroperoxide oxidation products which absorb in the infra-red region of the spectrum with maxima at 1710 and 3410 cm-', respectively. During photooxidation the rutile pigment is synergistic in stabilisation with phenolic antioxidants and hindered piperidine stabilisers (HAS) but antagonistic with benzotriazole and benzophenone absorbers. In the case of anatase marked autocatalytic oxidation is observed giving strong antagonistic effects. With mixed antioxidant/stabiliser combinations, synergistic stabilisation is not significantly influenced by rutile but markedly antagonised by the presence of the anatase pigment. The most effective light stabiliser in retarding the catalytic oxidative effect of anatase is the polymeric HAS, Chimassorb 944. During thermal oxidation the polymeric HAS exhibit strong thermal antioxidant activity compared with the non-polymeric HAS. Both antioxidants and the benzophenone absorber are strongly antagonistic with rutile while the HAS and benzotriazole stabilisers display weak synergism. The anatase strongly accelerated and catalysed the thermal stabilisation effects with all the stabilisers and antioxidants. For the stabiliser combinations, the HAS are more effective at inhibiting oxidative degradation than the absorbers in the presence of both pigment types. The thermal catalytic effects of anatase are strongly suppressed by antioxidant/stabiliser combinations. 0 1998 Elsevier Science Limited. All rights reserved

Interactions of melatonin with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) were investigated as a function of temperature and melatonin concentration (1-30 mol%) by using two noninvasive techniques, namely Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The investigation of the C-H, CMO, and PO 2 À antisymmetric double stretching modes in FTIR spectra and DSC studies reveal that melatonin changes the physical properties of the DPPC bilayers by decreasing the main phase transition temperature, abolishing the pretransition, ordering the system in the gel phase, and increasing the dynamics of the system both in the gel and liquid crystalline phases. It also causes significant decrease in the wavenumber for the CMO stretching and PO 2 À antisymmetric double bond stretching bands, which indicates strong hydrogen bonding The results imply that melatonin locates in the interfacial region of the membrane. Furthermore, in the DSC curve, more than one signal is observed at high melatonin concentrations (24 and 30 mol%), which indicates melatonin-induced phase separation in DPPC membranes. D

- by ipek sahin
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- Chemical Engineering, FTIR spectroscopy, Biological Sciences, Melatonin

This study examines and compares the structural and rheological properties of succinoglycan exopolysaccharide made by fermentation of sucrose or date syrup at identical temperature, pH, and total soluble solid. Using thin-layer chromatography (TLC), Fourier transform infrared (FTIR) spectroscopy, and rotational viscometery structural and rheological properties of prepared exopolysaccharides were assessed. The variables under studies were biogum concentrations (0.5%, 1.0%, 1.5%, and 2.0% w/w), temperature (5, 25 and 40°C), and pH (2.5, 4.0, 7.0, and 10.0). Results revealed that the quantity of exopolysaccharide produced in the date syrup (DSE) medium was three to five times greater than that of sucrose (SE) medium. The biogums exhibited non-Newtonian, shear-thinning behavior, and the viscosity of DSE was higher than SE at all tested concentrations. The TLC and FTIR spectroscopy assessments designated that the biogum is composed of glucose and galactose units, carrying a carboxylic group and indicated the presence of succinoglycan. The outcomes of this study could be useful to food industries seeking low cost biogum.

- by Asgar Moosavi
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- FTIR spectroscopy, Food Industry, Rheological properties, Thin Layer Chromatography