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AbstractThis review presents a critical examination of the interface for coupling high performance liquid chromatography (HPLC) with Fourier transform infrared spectrometry (FTIR) since 2010. This coupling offers a robust analytical approach characterized by exceptional chemical specificity and the capacity to analyze complex multi-component mixtures qualitatively and quantitatively with high sensitivity, particularly in low limit of detection ranges. This coupling enables the identification of individual components of a mixture by IR after their separation by HPLC, although challenges arise from the potential distortion of infrared spectra by mobile phase components. Addressing this issue necessitates the implementation of suitable interfaces, such as flow cells or off-line indirect measurement methods like hot inert gas streams or ultrasonic nebulizers. The key parameters influencing the coupling of HPLC-FTIR include the solvent elimination methods, mode of FTIR technique, and IR background for accurate analyte identification. Moreover, the composition of the mobile phase and the utilization of buffer solutions in the HPLC mobile phase profoundly impact analyte identification by FTIR. [ABSTRACT FROM AUTHOR]

This study explores the relationship between natural fiber filling density (10%, 15%, 25%) and its impact on the bending properties of polymer compounds reinforced with Diss, Sisal and Luffa fibers. Using advanced techniques like fiber analysis and Fourier transform infrared spectrometry (FTIR), the research reveals that a 25% filling density results in the highest stress values (25.61 MPa, 22.21 MPa and 20.88 MPa) for Diss, Sisal and Luffa compounds, respectively, fostering robust bonds in Diss-reinforced polymers. The Artificial Neural Network (ANN) model demonstrates superior predictive capability with correlation coefficients exceeding 0.99 for stress and displacement, outperforming Response Surface Methodology (RSM). Analysis of Variance (ANOVA) underscores the impact of sample section parameters and fiber rate on stress, establishing the significance of type parameters and fiber rate on displacement. This integration of ANN and RSM represents a paradigm shift in predicting bending mechanical properties, advancing our understanding of composite materials for innovative applications. [ABSTRACT FROM AUTHOR]

Chitosan is a natural polysaccharide which has been authorized for oenological practices for the treatment of musts and wines. This authorization is limited to chitosan of fungal origin while that of crustacean origin is prohibited. To guarantee its origin, a method based on the measurement of the stable isotope ratios (SIR) of carbon δ13C, nitrogen δ15N, oxygen δ18O and hydrogen δ2H of chitosan has been recently proposed without indicating the threshold authenticity limits of these parameters which, for the first time, were estimated in this paper. In addition, on part of the samples analysed through SIR, Fourier transform infrared spectrometry (FTIR) and thermogravimetric analysis (TGA) were performed as simple and rapid discrimination methods due to limited technological resources. Samples having δ13C values above −14.2‰ and below −125.1‰ can be considered as authentic fungal chitosan without needing to analyse other parameters. If the δ13C value falls between −25.1‰ and −24.9‰, it is necessary to proceed further with the evaluation of the parameter δ15N, which must be above +2.7‰. Samples having δ18O values lower than +25.3‰ can be considered as authentic fungal chitosan. The combination of maximum degradation temperatures (obtained using TGA) and peak areas of Amide I and NH2/Amide II (obtained using FTIR) also allows the discrimination between the two origins of the polysaccharide. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) based on TGA, FTIR and SIR data successfully distributed the tested samples into informative clusters. Therefore, we present the technologies described as part of a robust analytical strategy for the correct identification of chitosan samples from crustaceans or fungi. [ABSTRACT FROM AUTHOR]

The paper proposes a model of tribotechnical diagnostics, which allows us to determine the technical condition of an internal combustion engine within its life cycle and then take measures, including its decommissioning due to excessive wear of major components. The paper also focuses on tribodiagnostic methods that are suitable for assessing the technical condition of internal combustion engines used in various means of transport (automobiles, railway locomotives powered by internal combustion engines, aircraft powered by reciprocating internal combustion engines, special and garden equipment). An internal combustion engine from agricultural equipment was selected for the experiment and monitored throughout its life cycle. The paper describes in detail the appropriate methods used for the proposed tribotechnical diagnostics model, including the results from the measurements by these methods. The said methods were then evaluated and mutually compared. The following advanced instrumental analytical methods were used to evaluate the collected engine oil samples: atomic emission spectrometry (AES), ferrography, automatic laser counter and LNF particle classifier, FTIR infrared spectrometry. The result of the work (paper) is the design of a tribotechnical diagnostics model for determining the technical condition of an internal combustion engine during its life cycle and the determination of limit values for assessing the technical condition of a Honda GCV 165 internal combustion engine. The results are based on individual measurements. [ABSTRACT FROM AUTHOR]

They were analyzed the thermal and rheological behavior of several varnishes and paints, used for wood protection, available on the market. The thermogravimetric analysis coupled with mass spectrometry and Fourier transform infrared spectrometry technique revealed that the degradation mechanism is complex and includes two to five decomposition stages depending on the composition. The analysis of the gases resulting from the decomposition processes of the water-based samples showed that carbon dioxide was the main potentially harmful product, whereas for those containing solvent these harmful agents were as follows: benzene, xylene and carbon dioxide. The decomposition of the sample containing urea-alkyd resins also results in hydrocyanic acid. The rheological tests showed a viscoelastic solid behavior in the case of water-based film-forming products, and a viscoelastic liquid behavior in the case of solvent-based ones. The microscale combustion calorimetry technique confirmed that this sample has the lowest thermal stability and can contribute the most to the triggering of fires. [ABSTRACT FROM AUTHOR]

The study presented here considers the analysis of a medical dataset for the identification of the stage of onset of COVID-19 coronavirus. These data, presented in previous work by the authors, have been subjected to extensive analysis and additional calculations. The data were obtained by analyzing blood samples of infected individuals at 1, 3, and 6 months after COVID-19 infection. Results were obtained from FTIR spectrometry experiments. The results indicate a very effective ability to identify the different states of infection, and between 1 and 6 months even perfect. Specific spectrometry wavelength ranges can also be distinguished as medical markers. [ABSTRACT FROM AUTHOR]

Chitosan is a natural polysaccharide which has been authorized for oenological practices for the treatment of musts and wines. This authorization is limited to chitosan of fungal origin while that of crustacean origin is prohibited. To guarantee its origin, a method based on the measurement of the stable isotope ratios (SIR) of carbon δ13C, nitrogen δ15N, oxygen δ18O and hydrogen δ2H of chitosan has been recently proposed without indicating the threshold authenticity limits of these parameters which, for the first time, were estimated in this paper. In addition, on part of the samples analysed through SIR, Fourier transform infrared spectrometry (FTIR) and thermogravimetric analysis (TGA) were performed as simple and rapid discrimination methods due to limited technological resources. Samples having δ13C values above −14.2‰ and below −125.1‰ can be considered as authentic fungal chitosan without needing to analyse other parameters. If the δ13C value falls between −25.1‰ and −24.9‰, it is necessary to proceed further with the evaluation of the parameter δ15N, which must be above +2.7‰. Samples having δ18O values lower than +25.3‰ can be considered as authentic fungal chitosan. The combination of maximum degradation temperatures (obtained using TGA) and peak areas of Amide I and NH2/Amide II (obtained using FTIR) also allows the discrimination between the two origins of the polysaccharide. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) based on TGA, FTIR and SIR data successfully distributed the tested samples into informative clusters. Therefore, we present the technologies described as part of a robust analytical strategy for the correct identification of chitosan samples from crustaceans or fungi.

UiO‐66 nanoparticles (NPs) were prepared by the solvothermal method using deep eutectic solvents (DESs) and compared to those prepared using the traditional solvent, dimethylformamide. A mixture of choline chloride:glycerol with a molar ratio of 1:2 was used as a green solvent to prepare the NPs. SEM, a Fourier transform infrared spectrometer, zeta potential, N2 adsorption/desorption, and surface area characterisations were used to characterise the NPs. Results showed that the NPs formed in the DES had a smaller size but the lower surface area and functionalised with new chemical groups due to the DES effect. Also, the modified metal–organic frameworks surface area increased by increasing the incubation time but decreased by increasing the temperature. [ABSTRACT FROM AUTHOR]

Fourier transform infrared (FTIR) spectrometry is commonly used for the identification of reference substances (RSs) in solid, liquid, or gaseous mixtures. An expert is generally required to perform the analysis, which is a bottleneck in emergency situations. This study proposes a support vector machine (SVM)‐based algorithm, the peak correlation classifier (PCC), designed to rapidly detect the presence of a specific threat or reference substance in a sample. While SVM has been used in various spectrographic contexts, it has rarely been used on FTIR spectra. The proposed algorithm discovers correlation similarities between the FTIR spectrum of the RS and the test sample and then uses SVM to determine whether or not the RS is present in the sample. The study also shows how the additive nature of FTIR spectra can be used to create 'synthetic' substances that significantly improve the detection capability and decision confidence of the SVM classifier. [ABSTRACT FROM AUTHOR]

Sugar palm fibers (SPF) are one of valuable natural fibers which are abundantly available in Malaysia as agricultural biomass. The aim of this study to investigate on the effects of alkali, silane, and combination between alkali (6%) and silane (2%) on physical and mechanical properties of SPF to improve interfacial bonding of SPF with thermoplastic polyurethane (TPU) matrices. Scanning electron microscopy and Fourier transform infrared spectroscopy was used to observe the effectiveness of the alkali and saline treatments in the removal of impurities. Silane treated SPF exhibits better tensile strength than those of alkali, alkali-silane treated and untreated SPF. Droplet test indicates that the interfacial stress strength (IFSS) of alkali and silane treated SPF are enhanced whereas silane treated fibers exhibit highest IFSS. It is assumed that fiber treatments will help to develop high performance SPF reinforced polymer composites for industrial applications.

Carbon quantum dots (CQDs) have been studied for years as one of the most promising fluorescent nanomaterials. Herein, CQDs were prepared rapidly by a simple, eco-friendly one-pot hydrothermal method in the presence of hydrogen peroxide. Different sizes of CQDs are obtained by changing the reaction time. X-ray photoelectron spectroscopy and Fourier transform infrared spectrometry demonstrated the existence of a large number of oxygen-containing groups on the surface of CQDs. The as-prepared CQDs exhibited bright yellow luminescence under UV light, they are applied for bioimaging of HeLa cells, and showed bright luminescence and excellent biocompatibility. [ABSTRACT FROM AUTHOR]

Coal, a flammable substance, is affected by spontaneous weathering and can be hazardous when exposed to thermally unstable conditions. Over the past few decades, numerous chemical disasters involving coal have occurred, resulting in many deaths. Therefore, strategies for the prevention of such disasters must be implemented to ensure human safety, avoid financial losses, and minimise adverse environmental effects. This study d e termined the thermal safety parameters and thermal hazards of lignitous and long flame coal by using thermogravimetry and differential scanning calorimetry. The characteristics of th e functional groups in coal and treated coal were observed through Fourier transform infrared spectrometry. The structures of coal and coal treated with an ionic liquid, namely l-butyl-3-me thylimidazolium, were observed through scanning electron microscopy. Finally, theoretical kinetic models we re applied to calculate th ermokinetic parameters and identify th e degree of thermal hazard p re sen t during periods of thermal instability. The results revealed that l-buty l-3-me thylimidazolium nitrate considerably reduced the probability of coal spontaneous combustion and the degree of hazard for long flame coal. Therefore, this ionic liquid could serve as an effective inhibitor of spontaneous combustion in long flame coal. [ABSTRACT FROM AUTHOR]

Automobile shredder residue (ASR) pyrolysis produces solid, liquid, and gaseous products, particularly pyrolysis oil and gas, which could be used as renewable alternative energy resources. Due to the primary pyrolysis reaction not being complete, the yield of gaseous product is low. The pyrolysis tar comprises chemically unstable volatiles before condensing into liquid. Understanding the characteristics of volatile products will aid the design and improvement of subsequent processes. In order to accurately analyze the chemical characteristics and yields of volatile products of ASR primary pyrolysis, TG–FTIR–GC/MS analysis technology was used. According to the analysis results of the Gram–Schmidt profiles, the 3D stack plots, and GC/MS chromatograms of MixASR, ASR, and its main components, the major pyrolytic products of ASR included alkanes, olefins, and alcohols, and both had dense and indistinguishable weak peaks in the wavenumber range of 1900–1400 cm−1. Many of these products have unstable or weaker chemical bonds, such as =CH–, =CH2, –C=C–, and –C=CH2. Hence, more syngas with higher heating values can be obtained with further catalytic pyrolysis gasification, steam gasification, or higher temperature pyrolysis.

Aerosol Optical Depth (AOD) and the Ångström Exponent (AE) have been calculated in the near infrared (NIR) and short-wave infrared (SWIR) spectral regions over a period of one year (May 2019–May 2020) at the high-mountain Izaña Observatory (IZO) from Fourier Transform Infrared (FTIR) solar spectra. The high-resolution FTIR measurements were carried out coincidentally with Cimel CE318-T photometric observations in the framework of the Aerosol Robotic Network (AERONET). A spectral FTIR AOD was generated using two different approaches: by means of the selection of seven narrow FTIR micro-windows (centred at 1020.90, 1238.25, 1558.25, 1636.00, 2133.40, 2192.00, and 2314.20 nm) with negligible atmospheric gaseous absorption, and by using the CE318-AERONET’s response function in the near-coincident bands (1020 nm and 1640 nm) to degrade the high-resolution FTIR spectra. The FTIR system was absolutely calibrated by means of a continuous Langley–Plot analysis over the 1-year period. An important temporal drift of the calibration constant was observed as a result of the environmental exposure of the FTIR’s external optical mirrors (linear degradation rate up to 1.75% month−1). The cross-validation of AERONET-FTIR databases documents an excellent agreement between both AOD products, with mean AOD differences below 0.004 and root-mean-squared errors below 0.006. A rather similar agreement was also found between AERONET and FTIR convolved bands, corroborating the suitability of low-resolution sunphotometers to retrieve high-quality AOD data in the NIR and SWIR domains. In addition, these results demonstrate that the methodology developed here is suitable to be applied to other FTIR spectrometers, such as portable and low-resolution FTIR instruments with a potentially higher spatial coverage. The spectral AOD dependence for the seven FTIR micro-windows have been also examined, observing a spectrally flat AOD behaviour for mineral dust particles (the typical atmospheric aerosols presented at IZO). A mean AE value of 0.53 ± 0.08 for pure mineral dust in the 1020–2314 nm spectral range was retrieved in this paper. A subsequent cross-validation with the MOPSMAP (Modeled optical properties of ensembles of aerosol particles) package has ensured the reliability of the FTIR dataset, with AE values between 0.36 to 0.60 for a typical mineral dust content at IZO of 100 cm−3 and water-soluble particle (WASO) content ranging from 600 to 6000 cm−3. The new database generated in this study is believed to be the first long-term time series (1-year) of aerosol properties generated consistently in the NIR and SWIR ranges from ground-based FTIR spectrometry. As a consequence, the results presented here provide a very promising tool for the validation and subsequent improvement of satellite aerosol products as well as enhance the sensitivity to large particles of the existing databases, required to improve the estimation of the aerosols’ radiative effect on climate.

Here, the authors report a rapid, simple, and eco‐friendly process for synthesis of Bi2 O3 nano‐needles. Dioscorea alata tuber extract was used as both reducing and capping agent for the first time. These nanoparticles were characterised by X‐ray diffraction, field emission scanning electron microscope, and Fourier transform infrared (FTIR) spectrometry, the nano‐structured Bi2 O3 needles have an average diameter of 158 nm with the lengths in the range of 1–3 μm. CLSI M27‐A2 standard was followed for evaluation of anti‐fungal activity. Bi2 O3 nano‐needles show remarkable activity against Candida albicans. It exhibits four time greater activity than bulk Bi2 O3 powder and two time greater activity than itraconazole, which makes it a potent anti‐fungal drug. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) possess negligible vapor pressure, a low toxicity, a low melting point, and a vast liquid temperature range, rendering them as favorable candidates for new alternative solvents. However, some recent studies showed that ILs are flammable during thermal upsets. To explore the overall spontaneous combustion under upset conditions, we propose a safer method to investigate the IL's thermal hazards. Gas chromatography/mass spectrometry, Fourier transform infrared spectrometry, and flash point analysis results indicated that 1-butylimidazolium nitrate ([BIM][NO3]) exhibits combustible characteristics and low thermal stability at high temperatures (over ca. 150.0 °C) during thermal decomposition. Meanwhile, differential scanning calorimetry, thermogravimetry, and vent sizing package 2 (VSP2) tests were used to describe the thermal properties of [BIM][NO3]. The thermokinetic parameters were further acquired by using an isoconversional method. The results demonstrate that the suitable combination of anion and cation might yield energetic ILs. [ABSTRACT FROM AUTHOR]

• Novel prediction approach for adiabatic runaway reaction. • Flammable components were detected in the pyrolysis gas production. • [BIM][NO3] thermal decomposition started at 125.0 °C. • [BIM][NO3] is unstable state at above 160.0 °C with drastic exothermic reaction. Ionic liquids (ILs) possess negligible vapor pressure, a low toxicity, a low melting point, and a vast liquid temperature range, rendering them as favorable candidates for new alternative solvents. However, some recent studies showed that ILs are flammable during thermal upsets. To explore the overall spontaneous combustion under upset conditions, we propose a safer method to investigate the IL's thermal hazards. Gas chromatography/mass spectrometry, Fourier transform infrared spectrometry, and flash point analysis results indicated that 1-butylimidazolium nitrate ([BIM][NO 3 ]) exhibits combustible characteristics and low thermal stability at high temperatures (over ca. 150.0 °C) during thermal decomposition. Meanwhile, differential scanning calorimetry, thermogravimetry, and vent sizing package 2 (VSP2) tests were used to describe the thermal properties of [BIM][NO 3 ]. The thermokinetic parameters were further acquired by using an isoconversional method. The results demonstrate that the suitable combination of anion and cation might yield energetic ILs. [ABSTRACT FROM AUTHOR]

Sugar palm fibers (SPF) are one of valuable natural fibers which are abundantly available in Malaysia as agricultural biomass. The aim of this study to investigate on the effects of alkali, silane, and combination between alkali (6%) and silane (2%) on physical and mechanical properties of SPF to improve interfacial bonding of SPF with thermoplastic polyurethane (TPU) matrices. Scanning electron microscopy and Fourier transform infrared spectroscopy was used to observe the effectiveness of the alkali and saline treatments in the removal of impurities. Silane treated SPF exhibits better tensile strength than those of alkali, alkali-silane treated and untreated SPF. Droplet test indicates that the interfacial stress strength (IFSS) of alkali and silane treated SPF are enhanced whereas silane treated fibers exhibit highest IFSS. It is assumed that fiber treatments will help to develop high performance SPF reinforced polymer composites for industrial applications. [ABSTRACT FROM AUTHOR]

Although cowside testing strategies for diagnosing hyperketonemia (HYK) are available, many are labor intensive and costly, and some lack sufficient accuracy. Predicting milk ketone bodies by Fourier transform infrared spectrometry during routine milk sampling may offer a more practical monitoring strategy. The objectives of this study were to (1) develop linear and logistic regression models using all available test-day milk and performance variables for predicting HYK and (2) compare prediction methods (Fourier transform infrared milk ketone bodies, linear regression models, and logistic regression models) to determine which is the most predictive of HYK. Given the data available, a secondary objective was to evaluate differences in test-day milk and performance variables (continuous measurements) between Holsteins and Jerseys and between cows with or without HYK within breed. Blood samples were collected on the same day as milk sampling from 658 Holstein and 468 Jersey cows between 5 and 20 d in milk (DIM). Diagnosis of HYK was at a serum ß-hydroxybutyrate (BHB) concentration =1.2 mmol/L. Concentrations of milk BHB and acetone were predicted by Fourier transform infrared spectrometry (Foss Analytical, Hillerød, Denmark). Thresholds of milk BHB and acetone were tested for diagnostic accuracy, and logistic models were built from continuous variables to predict HYK in primiparous and multiparous cows within breed. Linear models were constructed from continuous variables for primiparous and multiparous cows within breed that were 5 to 11 DIM or 12 to 20 DIM. Milk ketone body thresholds diagnosed HYK with 64.0 to 92.9% accuracy in Holsteins and 59.1 to 86.6% accuracy in Jerseys. Logistic models predicted HYK with 82.6 to 97.3% accuracy. Internally cross-validated multiple linear regression models diagnosed HYK of Holstein cows with 97.8% accuracy for primiparous and 83.3% accuracy for multiparous cows. Accuracy of Jersey models was 81.3% in primiparous and 83.4% in multiparous cows. These results suggest that predicting serum BHB from continuous test-day milk and performance variables could serve as a valuable diagnostic tool for monitoring HYK in Holstein and Jersey herds. [ABSTRACT FROM AUTHOR]

This Research Communication investigated the potential of mid-infrared spectroscopy to predict detailed mineral composition of bovine milk. A total of 153 bulk milk samples were analysed for contents of Ca, Cl, Cu, Fe, K, Mg, Na, P and Zn. Also, soluble and colloidal fractions of Ca, Mg and P were quantified. For each milk sample the mid-infrared spectrum was captured and stored. Prediction models were developed using partial least squares regression and the accuracy of prediction was evaluated using both cross- and external validation. The proportion of variance explained by the prediction models in cross-validation ranged from 34% (Na) to 77% (total P), and it ranged from 13% (soluble Mg) to 54% (Cl-) in external validation. The ratio of the standard deviation of each trait to the standard error of prediction in external validation, which is an indicator of the practical utility of the prediction model, was low and never greater than 2. Results from the current study supported the limited usefulness of mid-infrared spectroscopy to predict minerals present in low concentration in bulk milk. For major mineral components, results from the present research did not match previous findings demonstrating the need for further studies using larger reference datasets. [ABSTRACT FROM AUTHOR]

In this study, we developed a multifunctional chromatographic medium by using iminodisuccinic acid (IDS) as ligand, γ-glycidoxypropyltrimethoxysilane (γ-GLDP) as spacer arm and silica as matrix. The medium was characterized by fourier transform infrared spectrometry (FT-IR). Binding capacity of IDS on chromatographic medium was determined by potentiometric titration. The effect of mass ratios (w/w) between silica and IDS on the medium synthesis was discussed. The optimal ratio of matrix, spacer arm and ligand was 1.5 g: 2.0 mL: 4.6 g. Based on different chromatographic modes, protein mixtures of bovine serum albumin, ribonuclease and lysozyme were successfully separated with IDS-Silica column and IDS-Cu(II)-Silica column, respectively. To examine metal chelating behavior of IDS-Silica stationary phase, optimal geometries and related parameters of complexes formed by IDS with Fe 3+ , Cu 2+ , Ni 2+ , Zn 2+ , Co 2+ and Ca 2+ were achieved by quantum computing. The stabilities of the complexes were predicted according to the results of theoretical calculation. Sorption capacities of IDS-Silica stationary phase for metal ions were determined by using offline frontal chromatography (FC) combined with inductively coupled plasma atomic emission spectrometry (ICP-AES). A good agreement was found between simulating results and experimental observations. The order of chelating strength of IDS-Silica medium for metal ions was Fe 3+ > Cu 2+ > Ni 2+ > Zn 2+ > Co 2+ > Ca 2+ . Compared with IDA-Silica, Asp-Silica and Glu-Silica stationary phases, IDS-Silica displayed a stronger chelating property for metal ion. [ABSTRACT FROM AUTHOR]

The emission of volatile compounds is an environmental and economic concern for CO2 capture by amine scrubbing. The condensation of amine species into aerosol is the main cause of volatile amine emissions. Current mitigation methods, including water wash, are not effective at preventing the atmospheric release of aerosol. This study focuses on the observation of aerosol at three amine scrubbing pilot plants. Fourier Transform Infrared Spectrometry (FTIR) sampling was performed in a pilot plant at the University of Texas at Austin. SO2 injection increased the emission of PZ solvent at a 1:1 molar ratio, and the injection of vaporized sulfuric acid increased amine emissions at a rate of 3 mols PZ/mol H2SO4. The slipstream pilot plant operated by the University of Kentucky utilized MEA to scrub CO2 from the flue gas stream of a coal-fired power plant. Bypassing caustic pretreatment and allowing SO2 to enter the absorber column increased MEA emissions. A 4% increase in the outlet CO2 resulted in a 10% reduction of amine emissions. A simplified water wash system was found to be ineffective at curtailing aerosol emissions. Phase Doppler Interferometry (PDI) and FTIR sampling were performed simultaneously at the National Carbon Capture Center. Using a blower between the water wash and absorber column instead of upstream of the absorber column resulted in a decrease in MEA emissions. The use of the intermediate blower instead of the upstream blower resulted in fewer, smaller aerosol drops. Decreasing the CO2 removal resulted in reduced amine aerosol emissions. Lower CO2 correlated with a lower aerosol concentration in the treated flue gas, but the aerosol sizes were significantly larger and resulted in overall increased amine emissions. Increasing the water wash temperature was found to increase average aerosol size and the amine concentration within the aerosol phase, resulting in an overall increase in amine emissions. By using the particle size distribution and aerosol concentration observed by PDI, the total liquid volume in the aerosol phase was calculated. Comparing this calculated quantity with the amine emissions observed using the FTIR allowed the approximate amine concentration in the aerosol phase to be determined. [ABSTRACT FROM AUTHOR]

Diesel engine emissions consist of several harmful gaseous species, some of which are regulated by stringent emission norms, while many others are not. These unregulated emission species are responsible for adverse environmental impact and serious health hazards upon prolonged exposure. In this study, a four-cylinder, 1.4 l , compression ignition (CI) engine was used for characterization of unregulated gaseous exhaust emissions measured at 2500 rpm at varying engine loads (0, 25, 50, 75 and 100%). The test fuels investigated were Karanja biodiesel blended with diesel (KB5, KB20), methanol blended with diesel (M5) and baseline mineral diesel. Fourier transform infrared (FTIR) emission analyzer was used to measure unregulated emission species and raw exhaust gas emission analyzer was used to measure regulated emission species in exhaust. Results show an increasing trend for some of the unregulated species from blends of biodiesel such as formaldehyde, acetaldehyde, ethanol, n- butane however methane reduced upon using these oxygenated fuel blends except methanol, compared to baseline mineral diesel. Nevertheless, no significant changes were observed for sulfur dioxide, iso -butane, n -octane, n -pentane, formic acid, benzene, acetylene and ethylene upon using biodiesel and methanol blends. [ABSTRACT FROM AUTHOR]

Direct sunlight absorption by trace gases can be used to quantify them and investigate atmospheric chemistry. In such experiments, the main optical apparatus is often a grating or a Fourier transform spectrometer. A solar tracker based on motorized rotating mirrors is commonly used to direct the light along the spectrometer axis, correcting for the apparent rotation of the Sun. Calculating the Sun azimuth and altitude for a given time and location can be achieved with high accuracy but different sources of angular offsets appear in practice when positioning the mirrors. A feedback on the motors, using a light position sensor close to the spectrometer, is almost always needed. This paper aims to gather the main geometrical formulas necessary for the use of a widely used kind of solar tracker, based on two 45° mirrors in altazimuthal set-up with a light sensor on the spectrometer, and to illustrate them with a tracker developed by our group for atmospheric research.

We describe a new scaffold-free three-dimensional (3D) cell culture model using cholesteryl ester based lyotropic liquid crystal (LC) substrates. Keratinocytes were deposited randomly on the LC surface where they self-assembled into 3D microtissues or keratinospheroids. The cell density required to form spheroids was optimized. We investigated cell viability using dead/live cell assays. The adhesion characteristics of cells within the microtissues were determined using histological sectioning and immunofluorescence staining. Fourier transform infrared spectroscopy (FTIR) was used to characterize the biochemistry of the keratinospheroids. We found that both cells and microtissues could migrate on the LC surface. The viability study indicated approximately 80% viability of cells in the microtissues up to 20 days of culture. Strong intercellular adhesion was observed in the stratification of the multi-layered microspheroids using field emission-scanning electron microscopy (FE-SEM) and histochemical staining. The cytoskeleton and vinculins of the cells in the microtissues were expressed diffusely, but the microtissues were enriched with lipids and nucleic acids, which indicates close resemblance to the conditions in vivo. The basic 3D culture model based on LC may be used for cell and microtissue migration studies in response to cytochemical treatment. [ABSTRACT FROM AUTHOR]

In the deep Earth, hydrogen mainly occurs as structural hydroxyl and molecular water in minerals and melts, constituting mobile and immobile aqueous components. Hydrous minerals contain hydrogen which occupies a specific structural position and constitutes an indispensable component of chemical formulae. On the other hand, nominally anhydrous minerals do not contain hydrogen in their chemical formulae, but can host trace amounts of water in structural position and lattice defect. The molecular water may occur in the lattice defect as fluid/melt inclusions in minerals. Even though the water content of nominally anhydrous minerals is very limited generally in the order of ppm (parts per million), they may play a significant role in influencing the physicochemical properties of mineral and rock systems. With the continuous improvement of modern instrumentations, the analytical methodology exhibits trends for higher spatial resolution, lower detection limit and integral multiple methods on the water amount and its isotopic ratio. Among these methods, Fourier transform infrared spectrometry remains the most widely used, while secondary ion mass spectrometry, continuous flow mass spectrometry, elastic recoil detection analysis and Raman spectrometry are promising. This paper provides a brief review on the methodological progress and their applications to the analysis of structural water in nominally anhydrous minerals. [ABSTRACT FROM AUTHOR]

The nature of the influence of organic matter (OM) on ammonium adsorption in lake sediments remains disputed. In this study, the kinetics and thermodynamics of ammonium adsorption were investigated on sediment samples with different OM contents (ignoring the effects of OM mineralization) previously collected from Lake Wuli, a northern bay of Lake Taihu, a shallow lake in southern China. The mechanisms of ammonium adsorption in these samples were characterized by Fourier transform infrared spectrometry and scanning electron microscopy. The results show that the ammonium adsorption capacity of the sediments is highly correlated with their OM content and with the humic content of the OM. The ammonium adsorption capacity of OM varies with its composition, i.e., with the surface properties of the different functional groups present. Indeed, humic acid was found to have a greater ammonium adsorption capacity by itself than when mixed with kerogen and black carbon, the mixture of the latter two components proving a better adsorbent than pure black carbon. [ABSTRACT FROM AUTHOR]

Wide use of dyes in production of fabric becomes the most problematic and generates high amount of liquid effluent pollutants to the surface water. The potential of waste materials, pineapple ( Ananas comosus) leaf powder and lime ( Citrus aurantifolia) peel powder, to remove Remazol Brilliant Blue R (RBBR) from aqueous solution through adsorption process was investigated. Batch experiments were conducted at initial dye concentration of 500 mg/L. Data analysis showed a removal percentage more than 90 %. The Langmuir, Freundlich, and Temkin isotherm models were also investigated to study the mechanism of dye molecules onto adsorption process. The optimum equilibrium was obtained by the Langmuir isotherm ( R = 0.9945) for pineapple leaves and ( R = 0.9994) for lime peel. The maximum monolayer adsorption capacity adsorbents onto RBBR (9.58 mg/g) were achieved. The pseudo-second-order kinetic indicates that the rate constant was 1.00. The specific area of both adsorbents was identified as homogenous structure and was characterized by field emission scanning electron microscopy (FESEM) analysis. The surface functional groups responsible for dye uptake by adsorbents indicate that both adsorbents were defined as carboxyl group which consists of carbonyl and hydroxyl groups and were analyzed by Fourier transform infrared spectrometry (FTIR) analysis. The overall study indicates that adsorbents prepared from pineapple leaves and lime peels are alternative low-cost product in dye removal from aqueous solution. [ABSTRACT FROM AUTHOR]

Magnetic polymer nanospheres were prepared and used as adsorbents for the extraction of organochlorine and pyrethroid pesticides from water samples. The adsorbents were synthesized by miniemulsion polymerization of N-vinylimidazole and divinylbenzene and simultaneous encapsulation of oleic acid-coated FeO nanoparticles. Following desorption with ethyl acetate, the target analytes β-hexachlorocyclohexane, δ-hexachlorocyclohexane, p,p'-DDE, heptachlor, trans-chlordan, cis-chlordan, bifenthrin, β-cypermethrin, δ-methrin, λ-cyhalothrin and esfenvalerate were determined by gas chromatography with electron capture detection. Desorption conditions, extraction times and sample volume were screened by Plackett-Burman design and optimized by Box-Behnken design. Under the optimum conditions, the organochlorines can be quantified in the 20 to 400 ng L concentration range, and the pyrethroids in the 400 to 4000 ng L concentration range. The recoveries of organochlorines and pyrethroids from spiked real water samples are between 77.6 and 97.3 %, with relative standard deviations between 0.9 and 10.0 %. The method for magnetic solid phase extraction described here is fast, simple and friendly to the environment. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The contribution of radiation to the apparent thermal conductivity of fiber reinforced cement composites exposed to a thermal pre-treatment up to 1000 °C is investigated using Fourier transform infrared (FTIR) spectrometry. The transmittance spectra are measured in the wavelength range of 2.5–16 μm. The radiative thermal conductivity is then calculated using the spectral extinction and Rosseland mean extinction coefficients. Experimental results show that for the analyzed materials radiation can represent up to 4.54% of the apparent thermal conductivity. The expanded uncertainty of the measurement is found within the range of 12.4–15.9%, being affected by the accuracy of the FTIR spectrometer in the most significant way. [ABSTRACT FROM AUTHOR]