Volatile organic compounds (VOCs) include endogenous metabolites that provide information about health and disease which might be useful to develop a better screening method for breast cancer. The goal of this study was to classify mice with and without tumors and compare tumors localized to the ...
Theoretical Simulation of Near-Infrared Spectrum of Piperine. Insight into Band Origins and the Features of Regression Models from Different Spectrometers Strong convolution of numerous overtones and combination bands makes NIR spectra difficult to interpret. Recent advances in anharmonic simulations decisive...
A man-portable membrane inlet mass spectrometer has been built and tested to detect and monitor characteristic odors emitted from the human body and also f
A new gas inlet port combined with a novel ionization scheme have been developed and coupled to a high-resolution time-of-flight mass spectrometer (TOF MS) for the detection and measurement of atmospheric volatile (VOCs) and intermediate volatility organic compounds (IVOCs). Ions are produced pred...
The time-honored approach to identifying an unknown pollutant involves comparing its EI mass spectrum with those compiled in spectral libraries. There are databases containing hundreds of thousands of EI spectra (e.g., the NIST Mass Spectral Library), but equivalent libraries compiling CID mass spect...
An integrated data matrix composed of average RT, average RI, EI spectrum, sample name, and corresponding peak area was generated. Then, the peak area from the data matrix was normalized using the locally weighted scatterplot smoothing (LOWESS) method prior to further statistical analysis. 2.9. ...
The kinds and concentrations of VOCs were compared precisely in the range of 120–170 °C in a 2D topographic (Figure 2B). The reference spectrum at 120 °C was utilized, and the spectra of other temperatures were obtained via subtraction. The red area in the figure indicates a higher VOC...
According to the retention time (RT) of n-alkane series (C7-C30) obtained under the same conditions, retention indices (RI) of the detected VOCs were computed. By comparing RI calculated and from the NIST library (NIST14, version 2.2, National Institute of Standards and Technology), the VOC...
To obtain an overall visual summary of the differences between the KWs made with and without peel, an unsupervised rPCA model was calculated for the concentrations of the seven VOCs of Table 1, as illustrated in Figure 2. Figure 2. Score plot (a) and Pearson correlation plot (b) of the ...
The spectroscopic and chromatographic data were obtained with a gas chromatograph, GCMS-QP2020 NX (SHIMADZU, Kyoto, Japan) with LabSolutions Insight software, which included the spectral library NIST. The volatiles were identified by comparison of the mass spectrum with the NIST14 mass spectrometry ...