The decolourization of Turquoise Blue HFG by immobilized cells of Lysinibacillus fusiformis B26 was investigated. Cells of L. fusiformis B26 were immobilized by entrapment in agar and calcium alginate matrices and attached in pumice particles. The effects of operational conditions (e.g., agar concentrations, cell concentrations, temperature, and inoculum amount) on microbial decolourization by immobilized cells were investigated. The results revealed that alginate was proven to be the best as exhibiting maximum decolourization (69.62%), followed by agar (55.55%) at 40°C. Pumice particles were the poorest. Optimum conditions for agar matrix were found: concentration was 3%, cell amount was 0.5 g and temperature was 40°C (55.55%). Ca-alginate beads were loaded with 0.5, 1.0 and 2.0 g of wet cell pellets and the highest colour removal activity was observed with 2.0 g of cell pellet at 40°C for alginate beads. Also, 0.5 and 1.0 g of pumice particles that were loaded with 0.25 and 0.5 g of cell pellets respectively were used and the results were found very similar to each other.
Open-Path Fourier Transform Infrared OP-FTIR spectrometers are commonly used for the measurement of atmospheric pollutants and of gases in industrial processes. Spectral interpretation for the determination of gas concentrations is based on the HITRAN database line-by-line modeling method. This article describes algorithms used to model gas spectra and to determine gas concentration under variable temperatures. Integration of individual rotational lines has been used to reduce the impact of spectrometer functions on the comparison of both measured and synthetic modeled spectra. Carbon monoxide was used as an example. A new algorithm for gas concentration retrieval consisting of two ensemble methods is proposed. The first method uses an ensemble of local models based on linear and non-linear PLS (partial least square) regression algorithms, while the second is an ensemble of a calibration set built for different temperatures. It is possible to combine these methods to decrease the number of regression models in the first ensemble. These individual models are appropriate for specific measurement conditions specified by the ensemble of the calibration set. Model selection is based on comparison of gas spectra with values determined from each local model
The paper presents the results of thermoanalytical studies by TG/DTG/DTA, FTIR and GC/MS for the oil sand used in art and precision foundry. On the basis of course of DTG and DTA curves the characteristic temperature points for thermal effects accompanying the thermal decomposition reactions were determined. This results were linked with structural changes occurred in sample. It has been shown that the highest weight loss of the sample at temperatures of about 320°C is associated with destruction of C-H bonds (FTIR). In addition, a large volume of gases and high amounts of compounds from the BTEX group are generated when liquid metal interacts with oil sand. The results show, that compared to other molding sands used in foundry, this material is characterized by the highest gaseous emissions and the highest harmfulness, because benzene emissions per kilogram of oil sand are more than 7 times higher than molding sand with furan and phenolic binders and green sand with bentonite and lustrous carbon carrier.
Sand samples with furan binder were prepared using Sand, Furfuryl Alcohol and Toluene Sulfonic Acid with ratio 100:0.85:0.30. To
identify and quantify gases releasing from furan binder various studies like FTIR, TGA and GC-MS were carried out. After analyzing our
materials using above mentioned characterizations the chemical formula of the Resin and Binder and amount of gases releasing from
composition were confirmed. After studying various reports on pyrolysis process of furan binder calculation of the % of various gases
emitting during pyrolysis process of furan was carried out. Sample of gas collected from mold was analyzed using GC-MS. Based on GCMS
measurement various gases emitting from furan sand mold were identified and their amount were calculate and compared with the
international standers of permissible gas emission limits in a foundry. The purpose of this paper is to assist foundries in pollution
prevention by devising clean technologies which maintain or improve the quality of ambient surrounding. This paper aimed at
minimization of pollution of air by using various techniques.
This paper addresses problems arising from in situ measurement of gas content and temperature. Such measurements can be considered indirect. Transmittance or natural radiation of a gas is measured directly. The latter method (spectral radiation measurement) is often called spectral remote sensing. Its primary uses are in astronomy and in the measurement of atmospheric composition. In industrial processes, in situ spectroscopic measurements in the plant are often made with an open path Fourier Transform Infrared (FTIR) spectrometer. The main difficulty in this approach is related to the calibration process, which often cannot be carried out in the manner used in the laboratory. Spectral information can be obtained from open path spectroscopic measurements using mathematical modeling, and by solving the inverse problem. Determination of gas content based on spectral measurements requires comparison of the measured and modeled spectra. This paper proposes a method for the simultaneous use of multiple lines to determine the gas content. The integrated absorptions of many spectral lines permits calculation of the average band absorption. An inverse model based on neural networks is used to determine gas content based on mid-infrared spectra at variable temperatures.
Fresh bituminous coal was stored in air-/water-oxidation conditions after 20 and 80 days, respectively. FTIR results show that the Hydrophilicity Index (HI) value of air-oxidized coal is higher than that of water-oxidized coal. SEM results show that the surface roughness of water-oxidized coal is higher than that of air-oxidized coal and water-oxidized coal surface has more holes and chips than air-oxidized coal surface. Flotation results show that the floatability of water-oxidized coal is worse than that of air-oxidized coal. The flotation performance of both air-/water-oxidized coals can be improved at larger collector dosages. The air-oxidation processes changed the HI value of coal greater than the water-oxidation processes while the water-oxidation processes changed the surface morphology of coal greater than the air-oxidation processes. Both the changes in HI value and surface roughness of coal determine the flotation behavior of oxidized coal. The changes in the surface morphology of coal particles after oxidation processes may be the primary factor determining the floatability of coal particles while the changes in the HI value of coal particles may be the inferior factor.
The electromagnetic field (EMF) is an environmental factor affecting living organisms. The aim of this study was to demonstrate the effect of an extremely low frequency electro- magnetic field (ELF-EMF) on selected chemical components of the honeybee (Apis mellifera L.) using Fourier Transform Infrared (FTIR) spectroscopy. The FTIR method provides information on the chemical structure of compounds through identification and analysis of functional groups. The honeybees were treated with EMF at a frequency of 50 Hz and magnetic induction of 1.6 mT for 2, 6, 12, 24 and 48 hours. Analysis of FTIR spectra showed that EMF exposure longer than 2 hours induced changes in the structure of chemical compounds, especially in the IR region corresponding to DNA, RNA, phospholipids and protein vibrations, compared to control samples (bees not EMF treated). The results confirm the effect of EMF on bees depending on the duration of exposure.
ZnO thin layers were deposited on p-type silicon substrates by the sol-gel spin-coating method and, then, annealed at various temperatures in the range of 573–873 K. Photoluminescence was carried out in the temperature range of 20–300 K. All samples showed two dominant peaks that have UV emissions from 300 nm to 400 nm and visible emissions from 400 nm to 800 nm. Influence of temperature on morphology and chemical composition of fabricated thin layers was examined by XRD, SEM, FTIR, and Raman spectroscopy. These measurements indicate that ZnO structure is obtained for samples annealed at temperatures above 573 K. It means that below this temperature, the obtained thin films are not pure zinc oxide. Thus, annealing temperature significantly affected crystallinity of the thin films.
Bismuth niobate (BiNbO4) ceramics were fabricated by mixed oxide method and sintered by presureless sintering method. BiNbO4 ceramics doped with V2O5 additive in amount 0.125 wt%, 0.250 wt% and 1 wt% of was sintered at T = 910°C whereas BiNbO4 ceramics doped with 2 wt% of CuO additive was sintered at T = 890°C and T = 910°C. It was found that V2O5 additive improved morphology of the ceramic samples. However, the chemical composition of BiNbO4 ceramics in relation to bismuth oxide and niobium oxide manifested a tendency of lack of Bi2O3 component. Absorption bands for the BiNbO4 compound were identified. FTIR band positions associated with NbO6 octahedra suggested that the crystal structure changes after V2O5 incorporation.
The use of torrefied biomass as a substitute for untreated biomass may decrease some technological barriers that exist in biomass co-firing technologies e.g. low grindability, high moisture content, low energy density and hydrophilic nature of raw biomass. In this study the TG-MS-FTIR analysis and kinetic analysis of willow (Salix viminalis L.) and samples torrefied at 200, 220, 240, 260, 280 and 300 °C (TSWE 200, 220, 240, 260, 280 and 300), were performed. The TG-DTG curves show that in the case of willow and torrefied samples TSWE 200, 220, 240 and 260 there are pyrolysis and combustion stages, while in the case of TSWE 280 and 300 samples the peak associated with the pyrolysis process is negligible, in contrast to the peak associated with the combustion process. Analysis of the TG-MS results shows m/z signals of 18, 28, 29 and 44, which probably represent H2O, CO and CO2. The gaseous products were generated in two distinct ranges of temperature. H2O, CO and CO2 were produced in the 500 K to 650 K range with maximum yields at approximately 600 K. In the second range of temperature, 650 K to 800 K, only CO2 was produced with maximum yields at approximately 710 K as a main product of combustion process. Analysis of the FTIR shows that the main gaseous products of the combustion process were H2O, CO2, CO and some organics including bonds: C=O (acids, aldehydes and ketones), C=C (alkenes, aromatics), C-O-C (ethers) and C-OH. Lignin mainly contributes hydrocarbons (3000-2800 cm−1), while cellulose is the dominant origin of aldehydes (2860-2770 cm−1) and carboxylic acids (1790-1650 cm−1). Hydrocarbons, aldehydes, ketones and various acids were also generated from hemicellulose (1790-1650 cm−1). In the kinetic analysis, the two-steps first order model (F1F1) was assumed. Activation energy (Ea) values for the first stage (pyrolysis) increased with increasing torrefaction temperature from 93 to 133 kJ/mol, while for the second stage (combustion) it decreased from 146 to 109 kJ/mol for raw willow, as well as torrefied willow at the temperature range of 200-260°C. In the case of samples torrefied at 280 and 300°C, the Ea values of the first and second stage were comparable to Ea of untreated willow and torrefied at 200°C. It was also found that samples torrefied at a higher temperature, had a higher ignition point and also a shorter burning time.
Silicate coatings have been considered as an alternative to toxic and carcinogenic other chemical treatments. In this paper, a strengthened silicate coating was formed on the surface of low carbon steel by dip immersion method. The modification and strengthening was done by loading colloidal nano-SiO2 into the film. The characterizations of nano-SiO2 were investigated by FESEM, TEM and FT-IR. The effects of nano contents (weight ratio) and drying temperatures on corrosion properties of silicate film were studied. Potentiodynamic polarization, electrochemical impedance spectroscopy and immersion tests have been used to study corrosion behavior of nano-loaded silicate films. Surface morphology, microstructure and its chemical composition were analyzed by means of FESEM, EDS, AFM, XRD, GIXRD, ATR-FTIR and Raman techniques. Results indicated that colloidal nano-SiO2 properly modified the silicate coatings and significantly improved the corrosion resistance and barrier property. Also drying temperature showed a considerable effect in silicate coating and higher corrosion resistance was obtained with 150°C curing.
A description of the status of the art of experimental and theoretical investigations of local crystalline structures of tetrahedron ordered ternary and quaternary semiconducting alloys is presented. Experimental EXAFS data and FTIR analysis are summarized and analyzed using both the Rigid Network Cations theoretical model and the Strained-tetrahedra model. Internal preferences of ion pairs in ternary and quaternary alloys are discussed. Several ternary systems of different structures show ideal quasi-canonical Bernoulli distributions, while others are characterized by extreme preferences in which one, several or even all configurations are depressed or even lacking. The results demonstrate that the validity of the Bernoulli distribution is limited and not fulfilled in many systems. This article is an expanded version of the scientific reports presented at the International Conference on Semiconductor Nanostructures for Optoelectronics and Biosensors 2016 ICSeNOB2016, May 22–25, 2016, Rzeszow, Poland.