scholarly journals The Use Of Chemical Composition And Additives To Classify Petrol And Diesel Using Gas Chromatography–Mass Spectrometry And Chemometric Analysis: A Uk Study

2019 ◽  
Vol 17 (1) ◽  
pp. 183-197 ◽  
Author(s):  
Praew Suppajariyawat ◽  
Ana Flavia Belchior de Andrade ◽  
Mathieu Elie ◽  
Mark Baron ◽  
Jose Gonzalez-Rodriguez

AbstractThe identification of the fuel found in a crime scene and establishing its source is important for forensic investigations. In this study petrol and diesel samples were analysed in order to identify chemical composition and additives with the aim of obtaining a set of markers or compounds that will allow forensic scientists to identify fuel sources. The study was performed using petrol and diesel sold in the city of Lincoln (UK) during four seasons (winter, spring, summer, autumn).Diesel samples, representing eight different brands were analyzed by gas chromatography−mass spectrometry (GC−MS) and principal component analysis (PCA). From the GC–MS analytical results, MTBE and ETBE were identified as the additive more preferably added in super unleaded petrol samples that can be used to aid in separation and identification. In diesel, the distribution of FAME contents showed the effect of seasonal variation as these were found in all spring, summer and autumn samples, but not found in all winter ones. The selection of a reduced number of key fuel compounds and additives was also shown to be sufficient to achieve a high level of classification among the different fuel samples. Leave–one–out cross–validation was applied in order to validate the results.

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1180
Author(s):  
Xiaoyu Yin ◽  
Qian Chen ◽  
Qian Liu ◽  
Yan Wang ◽  
Baohua Kong

Smoking is mainly used to impart desirable flavour, colour and texture to the products. Various food smoking methods can be divided into traditional and industrial methods. The influences of three different smoking methods, including traditional smouldering smoke (TSS), industrial smouldering smoke (ISS) and industrial liquid smoke (ILS), on quality characteristics, sensory attributes and flavour profiles of Harbin red sausages were studied. The smoking methods had significant effects on the moisture content (55.74–61.72 g/100 g), L*-value (53.85–57.61), a*-value (11.97–13.15), b*-value (12.19–12.92), hardness (24.25–29.17 N) and chewiness (13.42–17.32). A total of 86 volatile compounds were identified by headspace solid phase microextraction combined with comprehensive two-dimensional gas chromatography mass spectrometry (GC × GC-qMS). Among them, phenolic compounds were the most abundant compounds in the all sausages. Compared with sausages smoked with smouldering smoke, the ILS sausages showed the highest content of volatile compounds, especially phenols, alcohols, aldehydes and ketones. Principal component analysis showed that the sausages smoked with different methods had a good separation based on the quality characteristics and GC × GC-qMS data. These results will facilitate optimising the smoking methods in the industrial production of smoked meat products.


2016 ◽  
Vol 78 (2) ◽  
Author(s):  
Nurrulhidayah Ahmad Fadzlillah ◽  
Abdul Rohman ◽  
Arieff Salleh Rosman ◽  
Farahwahida Mohd Yusof ◽  
Amin Ismail ◽  
...  

Butter is high priced product; as a consequence, butter can be subjected for adulteration with low price components such as lard. The presence of lard in any products is not allowed for Muslim and Jewish, therefore, its presence must be identified. Gas chromatography-mass spectrometry was successfully used to detect and discriminate butter from adulterated with lard. Results were presented in the form of chromatogram. Principal component analysis (PCA) was used to interpret the data and provided a good grouping of samples with 55.8% of the variation accounted for by PC 1 and 21.5% were accounted for by PC 2. All the lard containing samples formed a separate group from the samples that were free of lard. This method can be developed into a rapid method for detecting the presence of lard in food samples for Halal authentication.


2019 ◽  
Vol 14 (5) ◽  
pp. 1934578X1985099 ◽  
Author(s):  
Tran Hui Thai ◽  
Nguyen Thi Hien ◽  
Le Ngoc Diep ◽  
Mathieu Paoli ◽  
Joseph Casanova ◽  
...  

Conifers are well represented in Vietnam where a new pine species has been recently discovered in Son La province: Pinus cernua, synonym P. armandii ssp. xuannhaensis. The compositions of needle, cone, and branch oils have been investigated by gas chromatography (retention index), gas chromatography-mass spectrometry, and 13C nuclear magnetic resonance. Myrcene (47.0%) was the main component of needle oil, followed by β-pinene (28.4%) and α-pinene (12.5%). Branch oil also contained myrcene (32.8%), α-pinene (17.9%), β-pinene (9.8%), and a high content of limonene (20.0%). Finally, cone oil displayed α-pinene (44.1%) beside myrcene (11.5%), β-pinene (8.1%), and limonene (5.8%).


2021 ◽  
Vol 117 (11/12) ◽  
Author(s):  
Pabalala M. Mthembi ◽  
Ellen M. Mwenesongole ◽  
Michael D. Cole

Nyaope, a Tswana word for a mixture or ‘mish-mash’, describes a drug cocktail consisting of heroin, cannabis, and on occasion other controlled substances and warfarin. It is highly addictive with extremely unpleasant side effects caused by withdrawal from the drug. It is a problem drug especially in townships in South Africa. However, its prevalence in neighbouring southern African states and further afield is not yet known. There is currently no validated method for the analysis and comparison of nyaope. We describe a validated method for the gas chromatography – mass spectrometry analysis of nyaope so that within-batch and between-batch comparisons of nyaope can successfully be made for the first time. The validated method managed an accuracy within the range 80–120%, the precision was less than 20% for all analytes and managed linearity with R2≥0.99. The detection limits for diamorphine, efavirenz, nevirapine and Δ9-tetrahydrocannabinol were 14.2, 18.6, 18.7 and 9.94 pg on column, respectively, and the limits of quantitation were 43.1, 56.3, 56.6 and 30.1 pg on column, respectively. The simulated and casework samples were successfully discriminated into original batches using the identified nyaope components, the unsupervised chemometric methods principal component analysis and hierarchical clustering, as well as chromatographic profiles.


2021 ◽  
Vol 58 (6A) ◽  
pp. 280
Author(s):  
Hung Huy Nguyen ◽  
Dai Ngoc Do ◽  
Prabodh Satyal ◽  
Chung Thanh Nguyen ◽  
Nguyen Van Bui ◽  
...  

The essential oil from the leaves of Callicarpa arborea Roxb. growing wild in Vietnam, was obtained by hydrodistillation and analyzed by gas chromatography – mass spectrometry. The major constituents of leaves of C. arborea were β-selinene (23.9%), ar-turmerone (17.5%) and α-copaene (8.9%), with lesser concentrations of caryophyllene oxide (4.9%) and ar-turmerol (3.9%). The chemical composition of this essential oil sample is being reported for the first time.


2018 ◽  
Vol 13 (1) ◽  
pp. 1934578X1801300
Author(s):  
Farukh S. Sharopov ◽  
Vasila A. Sulaymonova ◽  
Yanfang Sun ◽  
Sodik Numonov ◽  
Isomiddin S. Gulmurodov ◽  
...  

Helichrysum thianschanicum Regel was collected from Khorugh town of Kuhistoni Badakhshon Autonomous Province of Tajikistan. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography – mass spectrometry. A total of 67 compounds were identified representing 88.4% of the total essential oil composition. The major components of H. thianschanicum essential oil were ( E)-1-(6,10-dimethylundec-5-en-2-yl)-4-methylbenzene (pentylcurcumene) (21.6%), β-selinene (6.4%), δ-selinene (3.8%), (2 E, 6 E)-farnesol (3.3%), nerol (4.1%) and neryl decanoate (4.2%). To our best knowledge, no previous studies have been reported on the chemical composition of the essential oil of H. thianschanicum.


Sign in / Sign up

Export Citation Format

Share Document