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There are many ways to identify fibres; however, since most of the tests are destructive or the sample preparation process is complex, most methods used to identify archaeological fibres have their limitations. Among the existing methods, Fourier Transform Attenuated Total Reflection Infrared (ATR-FTIR) technology is relatively simple, fast and non-destructive, and the results are more accurate and reliable. In this study, four samples of ancient Chinese fibre, yarn, and fabric were identified using ATR-FTIR technology. Spectra of fingerprints show that the characteristics of cotton, linen, and wool are clear. The spectra of archaeological cotton fibre and modern cotton fibre are compared and analyzed. The results show that as a non-destructive method for analyzing surface composition of materials, ATR-FTIR technology is suitable for the identification of archaeological fibres.

The purpose of this paper is to check the actual life of lubricating oil.

Present work aims to find the remaining useful life of the lubricant based on study of periodic deterioration of oil. Chronological samples of oil were selected from the dumper of a local open cast mine. The deterioration in oil was studied using Fourier transform infrared (FTIR) spectroscopy.

The data obtained from FTIR spectroscopy was used in vector projection approach and analytical hierarchy process to evaluate the remaining useful life of the lubricating oil.

FTIR spectra were used to study the periodic deterioration of oil. IR radiation with all frequencies in the range was passed through the sample. Radiations at certain frequency, depending upon the molecular structure of compounds in the sample were absorbed and rest was transmitted by the sample. A spectrum representing molecular absorption or transmission was obtained. Transmission spectra have been used in the study. Comparing the percent value of transmission peak of different chronological sample with that of fresh oil was used to represent the periodic degradation in oil.

This study aims to using Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and scanning electron microscope/energy dispersive Xray spectrometer to identify different automotive coatings for forensic purpose.

Two four-layered samples in a hit-and-run case were compared layer by layer with three different methods. FTIR spectroscopy was used to primarily identify the organic and inorganic compositions. Raman spectrum and scanning electron microscope/energy dispersive Xray spectrometer (SEM-EDS) were further used to complement the FTIR results.

Two weak and tiny peaks in one layer found between two samples by FTIR, Raman microscope and SEM-EDS verified the result of differences. The study used the three instruments in combination and found it’s effective in sensing coatings, especially in the inorganic additives.

Using these three instruments in combination is more accurate than individually in multilayered coating analysis for forensic purpose.

The three different instruments all present unique information on the composition, and provided similar and mutually verifiable results on the two samples.

With this method, scientists could identify and discriminate important coating evidences with tiny but characteristic differences.

The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.

The analytical techniques used for chemical structures and compositions including Fourier transform infrared spectrometer (FTIR), scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are conducted.

The residues on the golden finger are identified to be the flux used in the assembly processes. Besides, the contaminants on the processed and incoming connector pins are verified to be polyamides (–CONH functional groups) from housing material's residue. Three liquid fluxes used in wave soldering are analyzed by their chemical structure. One flux showing the OH groups at 3430 cm⁻¹ indicates higher acid contents. This consists with the acidic values specified by the supplier. Also, the solder mask under study has ever appeared peeled‐off issue. The FTIR spectra results indicated 62.2 percent degree of curing while vendor's spec is above 70 percent.

The establishment of the Infrared spectra database for fluxes and process materials help determine the root cause of the contaminants to reduce re‐occurrence of similar problems and thus enhance the manufacturing capability. The infrared spectrophotometry technique can be used by professional original design manufacturing and/or electronics manufacturing service, providers to investigate board/component defects during product pilot run stage and volume production.

The purpose of this paper is to identify different automotive coatings using Confocal Raman microscope which could hardly be differentiated with Fourier transform infrared microscope (FTIR).

Raman spectroscopy was used to provide extra vibration information to infrared spectroscopy. Paints preparation was not necessary, and only 30 s was needed for each sample in an optimised method. Paints were first analysed by FTIR and then compared with Raman microscope.

Raman microscope was used to address the lack of ability of FTIR in discriminating four groups of paints in same colours. This study indicated that Raman microscopy is especially effective in sensing pigments and could successfully identify all pigments in the paints.

The two instruments in combination produce accurate results than when used individually, especially in complex and multi-layered paints analysis.

The method proved to be fast, accurate and non-destructive, and it could be easily applied to real cases.

With this method, scientists could discriminate some coating types which were hard to be discriminated by other techniques.

Ghee, anhydrous milk fat, is chemically highly complex in nature. The authentication and characterization of edible fats and oils by routine chemical methods are highly laborious and time consuming. Fourier transform-mid-infrared (FT-MIR) spectroscopy has emerged as a predominant analytical tool in the study of edible fats/oils. However, sufficient attention has not been paid so far to spectral characterization of milk fat obtained from cow and buffalo milk. The purpose of this paper is to fill this void.

Ghee samples were prepared from cow and buffalo milk by the direct cream method. From each type of milk (cow and buffalo), 35 samples of ghee were prepared; thus, in total, 70 samples of ghee were obtained for the study. For assigning absorption bands in the IR spectrum, spectra of cow and buffalo ghee samples were acquired in the MIR region (4,000-650 cm⁻¹).

In FT-MIR spectra of ghee, 14 peaks were obtained at different positions and with varying intensities. They were at 3,005, 2,922, 2,853, 1,744, 1,466, 1,418, 1,377, 1,236, 1,161, 1,114, 1,098, 966, 870 and 721 cm⁻¹ for cow and buffalo ghee with almost equal intensity of absorption.

The finding of this study will be useful for characterization and authentication of ghee.

Application of IR spectral bands of ghee in the MIR region using a FT-infrared spectrometer to monitor the quality of ghee is suggested.

Applies Fourier transform infrared spectroscopy (FTIR) to the study of lac resin, a complex natural resin of insect origin, and some of its derivatives. Compares the result obtained by this method with those from earlier studies that used classical methods of chemical analysis (the so‐called wet methods). Finds that FTIR has several advantages over the classical methods but, as spectroscopic assignments are still only tentative because of the complex nature of the lac resin, the FTIR data requires supplementing by other instrumental techniques such as FT‐Raman spectroscopy and solid state nuclear magnetic resonance.

Three common glob top encapsulant materials, two epoxy‐based, and one silicone‐based, were characterized prior to temperature cycling using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical spectroscopy (DMS), gas chromatograph‐mass spectrometry (GC‐MS), and Fourier transform infrared spectroscopy (FTIR). After cycling between ‐55 to +125°C, for 1,000 cycles, the same samples were again analysed using DMS and FTIR. For the epoxy‐based samples, the DMS results indicated that temperature cycling in a humid environment can seriously affect the physical and mechanical properties of these samples. FTIR data also indicated that the molecular changes in the epoxy‐based samples appeared quite extensive after cycling, indicating a high level of degradation on the molecular scale. On the other hand, the silicon‐based glob top appeared to have survived the temperature cycling quite well.

Consumption of game meat is growing when compared to other meats. It is susceptible to adulteration because of its cost and availability. Spectroscopy may lead to rapid methodologies for detecting adulteration. The purpose of this study is to detect the adulteration of wild fallow deer (Dama dama) meat with domestic goat (G) (Capra aegagrus hircus) meat, for samples stored for different periods of time using Fourier transform infrared (FTIR) spectroscopy coupled with chemometric.

Meat was cut and mixed in different percentages, transformed into mini-burgers and stored at 3°C from 12 to 432 h and periodically examined for FTIR, pH and microbial analysis. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were applied to detect adulteration.

The PCA model, applied to the spectral region from 1,138 to 1,180, 1,314 to 1,477, 1,535 to 1,556 and from 1,728 to 1,759 cm⁻¹, describes the adulteration using four principal components which explained 95 per cent of variance. For the levels of Adulteration A1 (pure meat), A2 (25 and 50 %w/wG) and A3 (75 and 100 %w/wG) for an external set of samples, the correlation coefficients for prediction were 0.979, 0.941 and 0.971, and the room mean square error were 8.58, 12.46 and 9.47 per cent, respectively.

The PLS-DA model predicted the adulteration for an external set of samples with high accuracy. The proposed method has the advantage of allowing rapid results, despite the storage time of the adulterated meat. It was shown that FTIR combined with chemometrics can be used to establish a methodology for the identification of adulteration of game meat, not only for fresh meat but also for meat stored for different periods of time.

The purpose of this study was to investigate the microstructural evolution and hydrolytic stability of poly(phenylborosiloxane) (PPhBS) to further use and develop the oligomers as heat-resistant modifiers.

PPhBS was synthesized by direct co-condensation of boric acid (BA) and phenyltriethoxysilane (PTEOS). The structural evolution of PPhBS at high temperature was investigated by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential thermal analysis (DTA), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and 29Si nuclear magnetic resonance (NMR) spectroscopy. In addition, the change in the morphology of the PPhBS powder was examined to demonstrate the evolution of the chemical bonds, and the hydrolytic stability of PPhBS was investigated by a combination of X-ray diffraction (XRD) analysis, measurement of the mass loss in water and FTIR spectroscopy.

The results revealed that a cross-linking network was gradually formed with increasing temperature through the condensation of the residual hydroxyl groups in PPhBS, and the Si-OH and B-OH bonds remained even at a high temperature of 450°C. Furthermore, heat treatment improved the hydrolytic stability of the oligomer. The hydrolysis of the B-O-B bonds in PPhBS was reversible, whereas the Si-O-Si and Si-O-B bonds were highly resistant to hydrolysis.

The prepared PPhBS can be used as a heat-resistant modifier in adhesives, sealants, coatings and composite matrices.

Investigation of the structural evolution of a polyborosiloxane at high temperature by DRIFTS is a novel approach that avoided interference from moisture in the air. The insoluble mass fraction and the FTIR spectrum of PPhBS washed with water were used to investigate the hydrolytic stability of PPhBS.