Journal articles: 'Static headspace method (SHS)'

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Trivedi, Manisha, Elsy Raynil John, Faraat Ali, Anuj Prakash, Robin Kumar, and Gyanendra Nath Singh. "Development and Validation of an Automated Gas Chromatography Method for Determination of Dichloromethane in Ampicillin Sodium by Using Capillary Column Technology." Current Pharmaceutical Analysis 16, no. 7 (August 17, 2020): 901–8. http://dx.doi.org/10.2174/1573412915666190416125604.

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Background: The main aim of the study was to develop an automated static headspace gas chromatography (SHS-GC) method for determination of dichloromethane (DCM) in ampicillin sodium by using a capillary column. Methods: SHS-GC also known as gas chromatography-headspace is the technique of choice due to its high sensitivity, excellent separation abilities, low limit of detection and simplicity of the instrumentation used for the technique. The headspace sampling method has more appropriate sensitivity than the direct injection method because it can clearly separate volatile analytes from the sample matrix and effectively concentrate them. Therefore, this method results in less complex sample preparation, decreased instrument contamination, and increased capillary column life. Results: The developed SHS-GC method showed symmetrical peak shape reasonable retention time for DCM. A linear relationship was obtained over the range of 2-240 μg mL-1 with a correlation coefficient (r2) of 0.993. The recovery, system precision and robustness of the method were within the acceptable values. The Limit of Detection (LOD) and Limit of Quantitation (LOQ) were 0.5 μg mL-1 and 2 μg mL-1 respectively. Conclusions: The results obtained in this study demonstrate that SHS-GC method is selective, precise, linear, accurate and robust for determination of dichloromethane in ampicillin sodium and its formulation (injection).

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Najdoska-Bogdanov, Menče, Jane B. Bogdanov, and Marina Stefova. "Changes in Volatile Compounds during Aging of Sweet Fennel Fruits-Comparison of Hydrodistillation and Static Headspace Sampling Methods." Natural Product Communications 11, no. 3 (March 2016): 1934578X1601100. http://dx.doi.org/10.1177/1934578x1601100326.

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Two extraction methods for subsequent gas chromatographic (GC) determination of volatiles from freshly harvested and aged fennel fruit samples ( Foeniculum vulgare Mill.,ssp. vulgare var. dulce) have been compared. Hydrodistillation followed by GC-FID and GC-MS analysis was used as a standard method for essential oil characterization, while static headspace followed by GC (SHS-GC-FID) was used as a comparative method for determination of volatile components. As the fennel fruit ages, there is a gradual loss of the volatile components as indicated by the lower yield of essential oil and lower content of volatiles, as indicated by the alternative SHS-GC-FID analysis. Slight differences observed for the main components ( trans-anethole, estragole, fenchone, and limonene) using the two methods are negligible, indicating that these volatiles did not undergo chemical transformation during the sample preparation procedures. A difference in anisaldehyde content was observed when the composition of the hydrodistilled essential oil was compared with the SHS-GC-FIDanalysis of volatiles and explanation for the variation of anisaldehyde content and the origin of other compounds was suggested. Comparison of the obtained results showed that limonene oxides, carvone and carveolare detectable in SHS-GC-FID analysis of the aged fennel fruits, while in hydrodistilled samples analyzed by GC-FID they were not present. Another observed difference was the appearance of products in significant amounts with higher retention times than trans-anethole, namely threo- and erythro-anethole β-hydroxymethylether and anethole glycol that are not detectable in the essential oil obtained by hydrodistillation. So, the relative abundance of the major components is comparable between these two methods for fennel seed up to 3 years from harvest and they can be used interchangeably depending on the purpose and amount of material. Furthermore, SHS-GC-FID can be used for assessment of maximum storage time and quality of fennel fruit suitable for human consumption.

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Zhang, Wei, and Xianrui Liang. "Headspace Gas Chromatography-Mass Spectrometry for Volatile Components Analysis in Ipomoea Cairica (L.) Sweet Leaves: Natural Deep Eutectic Solvents as Green Extraction and Dilution Matrix." Foods 8, no. 6 (June 11, 2019): 205. http://dx.doi.org/10.3390/foods8060205.

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In this study, natural deep eutectic solvents (NADESs) were used as both the extraction and dilution matrix in static headspace gas chromatography-mass spectrometry (SHS-GC-MS) for the analysis of volatile components in Ipomoea cairica (L). Sweet (ICS) leaves. Six NADESs were prepared and the NADESs composed of choline chloride and glucose with a 1:1 molar ratio containing 15% water were preferred due to the better peak responses. A total of 77 volatiles in ICS leaves were detected and tentatively identified by mass spectral matching with the US National Institute of Standards and Technology (NIST, 2014) Mass Spectral Library and the retention index-assisted qualitative method. These 77 volatile components were mainly terpenoids, aromatics, and aliphatics. Among them, β-elemene, β-caryophyllene, α-humulene, and 2, 4-di-tert-butylphenol were found to be the main components. This investigation verified that the use of NADESs is an efficient green extraction and dilution matrix of the SHS-GC-MS method for direct volatile component analysis of plant materials without extra extraction work.

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Sugaya, Naeko, Mitsuko Takahashi, Katsumi Sakurai, Maiko Tahara, and Tsuyoshi Kawakami. "Headspace GC/MS Analysis of Residual Solvents in Dietary Supplements, Cosmetics, and Household Products Using Ethyl Lactate as a Dissolution Medium." Journal of AOAC INTERNATIONAL 103, no. 2 (March 2020): 407–12. http://dx.doi.org/10.5740/jaoacint.19-0260.

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Abstract Background: The static headspace technique is one of the most popular techniques for residual solvent analysis and dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) are widely use as the dissolution media. Objective: This study aims to establish ethyl lactate (EL), a solvent with low toxicity and less environmental impact, as an alternative dissolution medium to DMSO and DMF for the static headspace analysis of toxic residual solvents in food, cosmetics, and similar complex organic matrices. Methods: Samples (a sample of dietary supplement and two samples each of cosmetics and household products) spiked with benzene, carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethene, and 1,1,1-trichloroethane were dissolved in EL, DMSO, and DMF. Static headspace GC/MS and the standard addition method were used to detect and quantify the residual solvents. Results: The dissolution and dispersion of these samples, especially the ones which were water-insoluble, were better than those in DMSO and DMF. The recoveries, except that of benzene in an aerosol spray, in EL ranged from 77 to 110%. The relative SDs in EL ranged from 2.5 to 11% and were better or equivalent to those in DMSO and DMF. Conclusions: EL was suitable as the dissolution medium for such samples, which may contain large amounts of organic solvents or various ingredients, in static headspace GC/MS analysis of residual solvents.

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Sakac, Marijana, Lato Pezo, Pavle Jovanov, Natasa Nedeljkovic, Anamarija Mandic, Mladenka Pestoric, and Aleksandra Misan. "Application of the SHS-GC-FID method and HPLC-DAD method in the prediction of the shelf-life of gluten-free cookies." Journal of the Serbian Chemical Society 82, no. 12 (2017): 1343–55. http://dx.doi.org/10.2298/jsc170421074s.

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The aim of this study was to compare the sensitivity of two analytical methods for the prediction of the shelf-life of unpacked and packed gluten-free rice?buckwheat cookies kept at ambient (23?1?C) and elevated (40?1?C) temperature during storage, namely the static headspace gas chromatographic method with flame ionisation detection (SHS-GC-FID) for volatile saturated aldehydes (propanal (C3), pentanal (C5), hexanal (C6), heptanal (C7) and octanal (C8)) and the HPLC method for malondialdehyde (MDA) determination. Both methods resulted in obtaining the same end-points of cookie shelf-life, i.e., 3 and 5 months for unpacked and packed cookies kept at elevated temperature, respectively, and 11 and 14 months for unpacked and packed cookies kept at ambient temperature, respectively. Two computational approaches, i.e., the second order polynomial (SOP) and artificial neural network (ANN) models, were used accordingly. The calculations of the contents of aldehydes and MDA could be predicted with an overall coefficient of determination of 0.722 using the ANN model compared to 0.312?0.773 for SOP models. According to sensitivity analysis, it might be suggested that the relevant parameter for the prediction of the end-point of cookie shelf-life is the MDA rather than the C3, C5, C6, C7 and C8 content.

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Bennett, Chonlada, Woraprapa Sriyotai, Sirakorn Wiratchan, Natthawat Semakul, and Sugunya Mahatheeranont. "Determination of 2-Acetyl-1-pyrroline via a Color-Change Reaction Using Chromium Hexacarbonyl." Molecules 27, no. 12 (June 20, 2022): 3957. http://dx.doi.org/10.3390/molecules27123957.

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At present, there is no colorimetric method for the quantitation of the aroma compound 2-acetyl-1-pyrroline (2AP). A novel colorimetric method was developed for the determination of 2AP content using chromium hexacarbonyl (Cr(CO)6) as a reagent. The reaction of synthetic 2AP with chromium hexacarbonyl reagent solution in the presence of light produced a green product with an absorption maximum (λmax) at 623 nm. GC–MS was used to confirm the color-change reaction, which showed the loss of 2AP after the addition of Cr(CO)6. This novel method enables facile and cost-effective determination of 2AP in fragrant rice. A comparative analysis of fragrant and nonfragrant rice grain extracts showed that no color-change reaction occurred with the nonfragrant rice sample. A limit of detection (LOD) of 2.00 mg L−1 was determined by method validation with an effective linear concentration ranging from 5.00 to 60.00 mg L−1 of 2AP. The results obtained using the developed colorimetric method were consistent with those obtained by automated static headspace gas chromatography with nitrogen-phosphorus detection (SHS-GC–NPD).

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Thammarat, Poowadol, Chadin Kulsing, Kanet Wongravee, Natchanun Leepipatpiboon, and Thumnoon Nhujak. "Identification of Volatile Compounds and Selection of Discriminant Markers for Elephant Dung Coffee Using Static Headspace Gas Chromatography—Mass Spectrometry and Chemometrics." Molecules 23, no. 8 (July 31, 2018): 1910. http://dx.doi.org/10.3390/molecules23081910.

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Elephant dung coffee (Black Ivory Coffee) is a unique Thai coffee produced from Arabica coffee cherries consumed by Asian elephants and collected from their feces. In this work, elephant dung coffee and controls were analyzed using static headspace gas chromatography hyphenated with mass spectrometry (SHS GC-MS), and chemometric approaches were applied for multivariate analysis and the selection of marker compounds that are characteristic of the coffee. Seventy-eight volatile compounds belonging to 13 chemical classes were tentatively identified, including six alcohols, five aldehydes, one carboxylic acid, three esters, 17 furans, one furanone, 13 ketones, two oxazoles, four phenolic compounds, 14 pyrazines, one pyridine, eight pyrroles and three sulfur-containing compounds. Moreover, four potential discriminant markers of elephant dung coffee, including 3-methyl-1-butanol, 2-methyl-1-butanol, 2-furfurylfuran and 3-penten-2-one were established. The proposed method may be useful for elephant dung coffee authentication and quality control.

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Carrillo, Jeniffer, and Cristhian Durán. "Fast Identification of Bacteria for Quality Control of Drinking Water through a Static Headspace Sampler Coupled to a Sensory Perception System." Biosensors 9, no. 1 (February 8, 2019): 23. http://dx.doi.org/10.3390/bios9010023.

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The aim of this study was to develop and implement a methodology composed by a Static Head-Space-Sampler (SHS) coupled to a Sensory Perception System (SPS) for the extraction of Volatile Organic Compounds (VOC’s) emitted by bacterial species in the water. The SPS was performed by means of a chamber of 16 Metal-Oxide-Semiconductor (MOS) gas sensors and a software with pattern recognition methods for the detection and identification of bacteria. At first, the tests were conducted from the sterile and polluted water with the Escherichia coli bacteria and modifying the incubation temperatures (50 °C, 70 °C and 90 °C), with the objective to obtain an optimal temperature for the distinguishing of species. Furthermore, the capacity of the methodology to distinguish the important compounds was assessed, in this case, E. coli and other bacteria like Pseudomonas aeruginosa and Klebsiella oxytoca, which formed similar analytes. The validation of the proposed methodology was done by acquiring water samples from different unitary operations of an aqueduct of the municipality of Toledo (North of Santander, Colombia), which were analyzed by the membrane filter technique in the laboratories of the University of Pamplona, along with the SHS-SPS system. The results showed that it was possible to distinguish polluted water samples in a fast way through the sensory measurement equipment using pattern recognition techniques such as Principal Component Analysis (PCA), Discriminant Function Analysis (DFA) and a probabilistic neural network (PNN), where a 95% of differentiation was obtained through PCA and 100% of the classification with DFA. The PNN network achieved the 86.6% of success rate with the cross-validation technique “leave one out”.

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Héthelyi, É., S. Szarka, É. Lemberkovics, and É. Szőke. "SPME-GC/MS identification of aroma compounds in rose flowers." Acta Agronomica Hungarica 58, no. 3 (September 1, 2010): 283–87. http://dx.doi.org/10.1556/aagr.58.2010.3.11.

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The content and composition of active ingredients and essential oils in medicinal and aromatic plants have been studied for several decades. The volatile compounds in essential oils have been analysed routinely using gas chromatography (GC) since 1966, and with GC coupled to mass spectrometric detection (GC/MS) since 1978.The 13 rose varieties selected for chemical analysis varied for colour, shape and fragrance. The static headspace solid phase microextraction (sHS-SPME) technique recently developed for sample preparation and sample enrichment was used to study the volatile aromatic components.The main volatile compound of a sweet-smelling purple rose was found to be phenyl ethyl alcohol (33–52%). The phenyl ethyl alcohol content of fragrant rose flowers with blackish-purple petals increased continuously from early summer to late autumn (from 17 to 70 %). The dominant aromatic components of the yellow, orange and pink rose flowers were hexanol, hexenyl acetate and benzyl alcohol. Phenyl ethyl alcohol and orcinol dimethyl ether were the main constituents of the fragrant pink and white rose varieties. Methyl vinyl anisol and orcinol dimethyl ether were dominant in rose flowers with beige petals. In summary, it can be concluded that the SPME-GC/MS method is suitable for the characterization of rose varieties and for the chemical analysis of aromatic volatile compounds.

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Jacq, Karine, Ed Delaney, Andrew Teasdale, Steve Eyley, Karen Taylor-Worth, Andrew Lipczynski, Van D. Reif, et al. "Development and validation of an automated static headspace gas chromatography–mass spectrometry (SHS-GC–MS) method for monitoring the formation of ethyl methane sulfonate from ethanol and methane sulfonic acid." Journal of Pharmaceutical and Biomedical Analysis 48, no. 5 (December 2008): 1339–44. http://dx.doi.org/10.1016/j.jpba.2008.09.028.

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Zedler, Łukasz, Marek Klein, Mohammad Reza Saeb, Xavier Colom, Javier Cañavate, and Krzysztof Formela. "Synergistic Effects of Bitumen Plasticization and Microwave Treatment on Short-Term Devulcanization of Ground Tire Rubber." Polymers 10, no. 11 (November 13, 2018): 1265. http://dx.doi.org/10.3390/polym10111265.

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Ground tire rubber (GTR) was mechano-chemically modified with road bitumen 160/220 and subsequently treated using a microwave radiation. The combined impact of bitumen 160/220 content and microwave treatment on short-term devulcanization of GTR was studied by thermal camera, wavelength dispersive X-ray fluorescence spectrometry (WD-XRF), static headspace, and gas chromatography-mass spectrometry (SHS-GC-MS), thermogravimetric analysis combined with Fourier transform infrared spectroscopy (TGA-FTIR), oscillating disc rheometer and static mechanical properties measurements. The obtained results showed that bitumen plasticizer prevents oxidation of GTR during microwave treatment and simultaneously improves processing and thermal stability of obtained reclaimed rubber.

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Alasalvar, C. "Method for the static headspace analysis of carrot volatiles." Food Chemistry 65, no. 3 (May 1999): 391–97. http://dx.doi.org/10.1016/s0308-8146(98)00202-7.

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Zedler, Łukasz, Daria Kowalkowska-Zedler, Henri Vahabi, Mohammad Reza Saeb, Xavier Colom, Javier Cañavate, Shifeng Wang, and Krzysztof Formela. "Preliminary Investigation on Auto-Thermal Extrusion of Ground Tire Rubber." Materials 12, no. 13 (June 28, 2019): 2090. http://dx.doi.org/10.3390/ma12132090.

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Ground tire rubber (GTR) was processed using an auto-thermal extrusion as a prerequisite to green reclaiming of waste rubbers. The reclaimed GTR underwent a series of tests: thermogravimetric analysis combined with Fourier-transform infrared spectroscopy (TGA-FTIR), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and static headspace and gas chromatography-mass spectrometry (SHS-GC-MS) in order to evaluate the impact of barrel heating conditions (with/without external barrel heating) on the reclaiming process of GTR. Moreover, samples were cured to assess the impact of reclaiming heating conditions on curing characteristics and physico-mechanical properties. Detailed analysis of the results indicated that the application of auto-thermal extrusion is a promising approach for the sustainable development of reclaiming technologies.

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de Pellegars, Pauline, Liu Pan, Rahima Sidi-Boulenouar, Eric Nativel, Michel Zanca, Eric Alibert, Sébastien Rousset, et al. "Homogenous nuclear magnetic resonance probe using the space harmonics suppression method." Journal of Sensors and Sensor Systems 9, no. 1 (March 26, 2020): 117–25. http://dx.doi.org/10.5194/jsss-9-117-2020.

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Abstract. Nuclear magnetic resonance imaging (MRI) has became an unavoidable medical tool in spite of its poor sensitivity. This fact motivates the efforts to enhance the nuclear magnetic resonance (NMR) probe performance. Thus, the nuclear spin excitation and detection, classically performed using radio-frequency coils, are required to be highly sensitive and homogeneous. The space harmonics suppression (SHS) method, already demonstrated to construct coil producing homogenous static magnetic field, is used in this work to design radio-frequency coils. The SHS method is used to determine the distribution of the electrical conductive wires which are organized in a saddle-coil-like configuration. The theoretical study of these SHS coils allows one to expect an enhancement of the signal-to-noise ratio with respect to saddle coil. Coils prototypes were constructed and tested to measure 1H NMR signal at a low magnetic field (8 mT) and perform MRI acquired at a high magnetic field (3 T). The signal-to-noise ratios of these SHS coils are compared to the one of saddle coil and birdcage (in the 3 T case) of the same size under the same pulse sequence conditions demonstrating the performance enhancement allowed by the SHS coils.

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Pizarro, Fritz, and Francisco Franco. "Volatile Organic Compounds at Early Stages of Sourdough Preparation Via Static Headspace and GC/MS Analysis." Current Research in Nutrition and Food Science Journal 5, no. 2 (July 27, 2017): 89–99. http://dx.doi.org/10.12944/crnfsj.5.2.05.

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Major aroma volatile compounds from whole wheat and all-purpose sourdough and their evolution were evaluated through static headspace gas chromatography-mass spectrometry (SHS-GC/MS) analysis during 28 days of fermentation. Sourdoughs were prepared on 1:1 ratio of flour to water (mass to volume) and fermented spontaneously at room temperature. GC/MS measurements for the evolution of aroma volatile compounds were conducted at 24, 168, 336, 504, and 672 hours of fermentation. Whole wheat sourdough contained more aroma volatile compounds (62) than all-purpose sourdough (45). The major aroma volatile compounds of whole wheat sourdough were hydrocarbons, esters, alcohols, ketones, aldehydes, and heterocycles. Meanwhile, aldehydes were dominant in the all-purpose sourdough. During whole wheat sourdough fermentation, a decrease in peak area percent was observed for aldehydes, ketones, and heterocycles, whereas an increase in the case of hydrocarbons. On the other hand, aldehydes dramatically increased in peak area percent for all-purpose sourdough. Aroma volatile compounds emanating from sourdough fermentation can aid consumers as well as manufacturers with regards to the quality, shelf-life, and what characteristic aromas the final bread product will possess.

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GIRARD, B., and S. NAKAI. "Static Headspace Gas Chromatographic Method for Volatiles in Canned Salmon." Journal of Food Science 56, no. 5 (September 1991): 1271–74. http://dx.doi.org/10.1111/j.1365-2621.1991.tb04750.x.

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Olesen, Bjorn. "An Economical Method for Static Headspace Enrichment for Arson Analysis." Journal of Chemical Education 87, no. 3 (March 2010): 314–15. http://dx.doi.org/10.1021/ed800078b.

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Robbins, Gary A., Suya Wang, and James D. Stuart. "Using the static headspace method to determine Henry's law constants." Analytical Chemistry 65, no. 21 (November 1993): 3113–18. http://dx.doi.org/10.1021/ac00069a026.

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Mandić, Anamarija I., Ivana J. Sedej, Marijana B. Sakač, and Aleksandra Č. Mišan. "Static Headspace Gas Chromatographic Method for Aldehyde Determination in Crackers." Food Analytical Methods 6, no. 1 (April 25, 2012): 61–68. http://dx.doi.org/10.1007/s12161-012-9415-5.

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Epping, Ruben, Lilly Bliesener, Tilman Weiss, and Matthias Koch. "Marker Substances in the Aroma of Truffles." Molecules 27, no. 16 (August 13, 2022): 5169. http://dx.doi.org/10.3390/molecules27165169.

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The aim of this study was to identify specific truffle marker substances within the truffle aroma. The aroma profile of different truffle species was analyzed using static headspace sampling with gas chromatography mass spectrometry analysis (SHS/GC-MS). Possible marker substances were identified, taking the additional literature into account. The selected marker substances were tested in an experiment with 19 truffle dogs. The hypothesis “If trained truffle dogs recognize the substances as supposed truffles in the context of an experiment, they can be regarded as specific” was made. As it would be nearly impossible to investigate every other possible emitter of the same compounds to determine their specificity, this hypothesis was a reasonable approximation. We were interested in the question of what it is the dogs actually search for on a chemical level and whether we can link their ability to find truffles to one or more specific marker substances. The results of the dog experiment are not as unambiguous as could have been expected based on the SHS/GC-MS measurements. Presumably, the truffle aroma is mainly characterized and perceived by dogs by dimethyl sulfide and dimethyl disulfide. However, as dogs are living beings and not analytical instruments, it seems unavoidable that one must live with some degree of uncertainty regarding these results.

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Müller, Christoph, Antonie L. Wagner, Ute Rockinger, Gerhard Winter, and Franz Bracher. "Development of a convenient method for the determination of dimethyl sulfoxide in lyophilised pharmaceuticals by static headspace gas chromatography-mass spectrometry." Analytical Methods 11, no. 16 (2019): 2119–22. http://dx.doi.org/10.1039/c8ay02574f.

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Sanchez-Cruz, Abraham, Norma Robledo, María Rosete-Enríquez, and Angel A. Romero-López. "Attraction of Adults of Cyclocephala lunulata and Cyclocephala barrerai (Coleoptera: Scarabaeoidea: Melolonthidae) towards Bacteria Volatiles Isolated from Their Genital Chambers." Molecules 25, no. 19 (September 27, 2020): 4430. http://dx.doi.org/10.3390/molecules25194430.

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In the study of the chemical communication of adults of the Melolonthidae family, bacteria have been observed in the epithelium of the genital chamber; possibly, bacteria are involved in the production of sex attractants in their hosts. Therefore, it is important to identify the volatile organic compounds from bacteria (VOCsB) released by these microorganisms and study the biological activity stimulated by VOBCs in adults of Melolonthidae. In this study, bacteria were isolated from the genital chamber of Cyclocephala lunulata and Cyclocephala barrerai, from which VOCsB were extracted using static headspace solid-phase microextraction (SHS-SPME) and dynamic headspace Super Q solid-phase extraction (DHS-SPE) and analyzed using gas chromatography-mass spectrometry. The effect of VOCsB on the hosts and conspecifics was evaluated utilizing an olfactometer and electroantennography (EAG). Two species of Enterobacteria were isolated from the genital chamber of each female species, and VOCsB derived from sulfur-containing compounds, alcohols, esters, and fatty acids were identified. An attraction response was observed in olfactometry studies, and antennal responses to VOCsB were confirmed in EAG bioassays. With these results, new perspectives on the relationship between these beetles and their bacteria emerge, in addition to establishing a basis for management programs in the future.

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Niyomwas, Sutham. "Synthesis of Composite Materials from Natural Precursors by Self-Propagating High Temperature Synthesis Process." Advanced Materials Research 488-489 (March 2012): 490–94. http://dx.doi.org/10.4028/www.scientific.net/amr.488-489.490.

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The composite materials have been synthesized in situ by self-propagating high temperature synthesis (SHS) from natural precursors. The studied natural resources are ilmenite, kaolin, sand and rice husk ash. The reactions were carried out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium compositions of the reacting species. The composites results have been characterized by scanning electron microscope (SEM), image analysis and X-ray diffraction (XRD). The results showed that the production of composite materials using SHS process is feasible and agree well with the thermodynamics calculations.

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Azarbad, Mohammad Hassan, and Henryk Jeleń. "Determination of Hexanal—an Indicator of Lipid Oxidation by Static Headspace Gas Chromatography (SHS-GC) in Fat-Rich Food Matrices." Food Analytical Methods 8, no. 7 (November 22, 2014): 1727–33. http://dx.doi.org/10.1007/s12161-014-0043-0.

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Tapsuan, Kunyaporn, and Sutham Niyomwas. "Effect of Al Mole Ratio on Iron Aluminide Reinforced with TiB₂-Al₂O₃ Composite by Self-Propagating High-Temperature Synthesis." Advanced Materials Research 488-489 (March 2012): 305–9. http://dx.doi.org/10.4028/www.scientific.net/amr.488-489.305.

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The Fe3Al-TiB2-Al2O3 composite has been prepared by self-propagating high-temperature synthesis (SHS) from FeTiO3-B2O3-Al system. The standard Gibbs energy minimization method was used to calculate the equilibrium compositions of the reacting species. The reactions were carried out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The effects of Al molar ratio of 4, 4.33 and 5 mole on the results product were investigated. The composition and microstructure of SHS products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The optimum result of Fe3Al intermetallics phase was obtained when using 4.33 mole of Al.

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Niyomwas, Sutham. "Synthesis of TiO₂-B₂O₃-Al Based Porous Composites." Advanced Materials Research 626 (December 2012): 1–5. http://dx.doi.org/10.4028/www.scientific.net/amr.626.1.

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The TiB2-Al2O3 porous composites were obtained in situ by self-propagating high temperature synthesis (SHS) of TiO2-B2O3-Al System. The reaction was carried out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The effects of increasing aluminum mole ratio to the precursor mixture of TiO2, B2O3 and Al were investigated. XRD and SEM analyses indicate complete reaction of precursors to yield TiB2-Al2O3 as product composite

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Shi, Guan-Yong, Ting-An Zhang, Zhi-He Dou, and Li-Ping Niu. "Dissolution Behavior of Al2O3 Inclusions in CaO-Al2O3 Based Slag Representing Aluminothermic Reduction Slag." Crystals 10, no. 11 (November 22, 2020): 1061. http://dx.doi.org/10.3390/cryst10111061.

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In the preparation of CuCr alloy using the self-propagating high-temperature synthesis (SHS)-metallurgy method, the dissolution of alumina in molten slag has an important influence in two key steps: aluminum thermal reduction and slag refining. In the present work, the dissolution behavior of Al2O3 into molten SHS-metallurgical slags was investigated by employing the rotating cylinder method and static dissolution method. It is concluded that the increase of MgO, CaF2, CaO, and Na3AlF6 contents can increase the dissolution rate of alumina in SHS-metallurgical slag, and the order of influence is from strong to weak. Both temperature and rotating speed can increase the dissolution rate, and the rate-limiting step is the diffusion of alumina in the boundary layer, with the solid alumina first reacting with lime to form two intermediate phases, CaO·2Al2O3 and CaO·6Al2O3, and finally dissolving into the slag in the form of an aluminum polymer.

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Shojania, S., M. E. McComb, R. D. Oleschuk, H. Perreault, H. D. Gesser, and A. Chow. "Article." Canadian Journal of Chemistry 77, no. 11 (November 1, 1999): 1716–27. http://dx.doi.org/10.1139/v99-142.

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An alternative sampling technique for fingerprint analysis of complex mixtures of petroleum-based products is presented. Fingerprint chromatograms of the volatile organic compounds (VOCs) for class 0-5 accelerants can be readily obtained using the recently developed inside needle capillary adsorption trap (INCAT) device. The concentration of VOCs from the static headspace of these complex mixtures, onto the adsorbing carbon coating of the INCAT device, avoids some problems associated with conventional headspace gas chromatography (HS-GC). The INCAT sampling method is a solventless extraction technique in which the analytes adsorbed inside the device are thermally desorbed inside the heated injection port of a gas chromatograph (GC), or a gas chromatograph coupled with a mass spectrometer (GC-MS). The presented method of active sampling with the INCAT device was used to obtain fingerprint chromatograms of the headspace of various gasolines, paint thinners, and lighter fluids. The static headspace chromatograms, from active sampling with the INCAT device, were compared with direct liquid injection of the samples. The INCAT chromatograms showed preferential adsorption of aromatic compounds over lighter, more volatile, but less polar compounds. Each class of the accelerant can be positively identified from the fingerprint chromatogram using only a few characteristic peaks. In addition, the ability to detect these volatile components of gasoline in aqueous samples at environmentally significant levels was also investigated.Key words: VOC, fingerprinting, INCAT, petroleum, headspace GC.

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Sidi-Boulenouar, Rahima, Ariston Reis, Eric Nativel, Simon Buy, Pauline de Pellegars, Pan Liu, Michel Zanca, et al. "Homogenous static magnetic field coils dedicated to portable nuclear magnetic resonance for agronomic studies." Journal of Sensors and Sensor Systems 7, no. 1 (April 4, 2018): 227–34. http://dx.doi.org/10.5194/jsss-7-227-2018.

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Abstract. Nuclear magnetic resonance (NMR) experiments are usually carried out at very high and homogenous magnetic fields. However, portable systems have emerged in recent years at low fields, offering many advantages like easier maintenance and open design that permit us to imagine a variety of coil configurations in order to maximize the homogeneity of the static field B0 and the radio-frequency field B1. The wire winding distribution based on space harmonics suppression (SHS) of the cosine current density distribution offers new possibilities of producing homogenous static fields B0. In this work, an extension of the SHS method, allowing homogeneity enhancement and flexibility of the coil design, is presented. The efficiency of the method is demonstrated through the construction of homogenous magnetic field coils dedicated to a very low magnetic field (8 mT) 1H NMR spectrometer. The performance of these coils in terms of magnetic field intensity and homogeneity as well as self-heating behavior is compliant with in planta experiments for agronomic studies.

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Iosefzon-Kuyavskaya, Berta. "Quality control in residual solvent analysis: the static headspace gas chromatographic method." Accreditation and Quality Assurance 4, no. 6 (May 31, 1999): 240–46. http://dx.doi.org/10.1007/s007690050359.

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Ang, Catharina Y. W., and Louis L. Young. "Rapid Headspace Gas Chromatographic Method for Assessment of Oxidative Stability of Cooked Chicken Meat." Journal of AOAC INTERNATIONAL 72, no. 2 (March 1, 1989): 277–81. http://dx.doi.org/10.1093/jaoac/72.2.277.

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Abstract Experiments were conducted to determine the volatile compounds in cooked chicken meat using a static headspace gas chromatographic (GC) technique. Preheating conditions for samples in vials were tested at 70,80, and 90°C for 20-120 min at each temperature. The majority of the peaks increased in size as the temperature and time increased. Optimum conditions were established as preheating at 80°C for 30 min followed by analysis on a packed column of 8% Poly MPE on Tenax GC with the temperature programmed from 50 to 200°C at 10°/min. Coefficients of variation for major peaks ranged from 8.3 to 14.7%. These results were compared with those obtained with a capillary column analysis of samples preheated at the same conditions. Cooked and stored chicken patties, pretreated with different levels of sodium tripolyphosphate, were analyzed by the thiobarbituric acid (TBA) method and the headspace GC technique. Significant positive correlations were obtained between TBA numbers and the areas of 3 major peaks of the headspace profiles, indicating the applicability of the rapid headspace GC method for the determination of oxidative changes in chicken meat.

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Miran Beigi, Ali Akbar, and Mojtaba Shamsipur. "Biochemistry Method: Simultaneous determination of formaldehyde and methyl tert-buthyl ether in environmental and human biological matrices using static headspace gas chromatography mass spectrometry." Analytical Methods in Environmental Chemistry Journal 2, no. 01 (March 21, 2019): 33–42. http://dx.doi.org/10.24200/amecj.v2.i01.40.

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The present study describes a method based on static headspace- extraction (HS) followed by gas chromatography/ mass spectrometry (GC/MS) for the qualitative and quantitative analysis of Methyl tert-buthyl ether (MTBE) and formaldehyde (HCHO) in human blood and water samples. Cytochrome P4502A6 has important role for converting of MTBE to tert-butyl alcohol (TBA) and HCHO. To enhance the extraction capability of the HS, extraction parameters such as extraction temperature, extraction time, the ratio of headspace volume to sample volume and sodium chloride concentration have been optimized.

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Gad, Mohamed, Hala Zaazaa, Sawsan Amer, and Mohamed Korany. "Static headspace gas chromatographic method for the determination of residual solvents in cephalosporins." RSC Advances 5, no. 22 (2015): 17150–59. http://dx.doi.org/10.1039/c5ra00125k.

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Lacy, Michael J., Gary A. Robbins, Suya Wang, and James D. Stuart. "Use of sequential purging with the static headspace method to quantify gasoline contamination." Journal of Hazardous Materials 43, no. 1-2 (September 1995): 31–44. http://dx.doi.org/10.1016/0304-3894(95)00024-o.

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Braga, Gilberto Costa, Adna Prado, Jair Sebastião da Silva Pinto, and Severino Matias de Alencar. "Volatile profile of yellow passion fruit juice by static headspace and solid phase microextraction techniques." Ciência Rural 45, no. 2 (February 2015): 356–63. http://dx.doi.org/10.1590/0103-8478cr20130777.

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The profile of volatile compounds of yellow passion fruit juice was analyzed by solid phase microextraction headspace (HS-SPME) and optimized static headspace (S-HS) extraction techniques. Time, temperature, NaCl concentration and sample volume headspace equilibrium parameters was adjusted to the S-HS technique. The gaseous phase in the headspace of samples was collected and injected into a gas chromatograph coupled to a mass spectrometer. In the HS-SPME technique was identified 44 volatile compounds from the yellow passion fruit juice, but with S-HS only 30 compounds were identified. Volatile esters were majority in both techniques, being identified ethyl butanoate, ethyl hexanoate, (3z)-3-hexenyl acetate, hexyl acetate, hexyl butanoate and hexyl hexanoate. Aldehydes and ketones were not identified in S-HS, but were in HS-SPME. β-Pinene, p-cymene, limonene, (Z)-β-ocimene, (E)-β-ocimene, γ-terpinene, α-terpinolene and (E) -4,8-dimethyl-1, 3,7 - nonatriene terpenes were identified in both techniques. This study showed that the S-HS optimized extraction technique was effective to recovery high concentrations of the major volatile characteristics compounds in the passion fruit, such as ethyl butanoate and ethyl hexanoate, which can be advantageous due to the simplicity of the method.

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Wei, Xin. "Synthesis of Alumina-Tungsten Carbide Composites by Self-Propagating High Temperature Synthesis Process." Advanced Materials Research 415-417 (December 2011): 226–31. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.226.

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Alumina-Tungsten Carbide (Al2O3-WC) composites were synthesized by self-propagating high temperature synthesis (SHS) from a powder mixture of WO3-C-Al. The reaction was carried out in a SHS reactor under static argon gas at a pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The effects of carbon mole ratio in precursor mixture and diluents of NaCl and Al2O3 on the Al2O3-WC conversion were investigated using X-ray diffraction and scanning electron microscope technique. The as-synthesized products of Al2O3-WC2-WC powders were concurrently formed and the reduction of W2C phase was found when added diluents in precursors.

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Chanadee, Tawat, Jessada Wannasin, and Sutham Niyomwas. "Investigations of Tungsten Based Intermetallic Alloys by Self Propagating High Temperature Synthesis from Metal Oxide Precursors." Advanced Materials Research 488-489 (March 2012): 300–304. http://dx.doi.org/10.4028/www.scientific.net/amr.488-489.300.

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The in-situself propagating high temperature synthesis technique were used to synthesis tungsten based intermetallic alloys from WO3/SiO2/Al and WO3/B2O3/Al reactant mixture system. The reaction was carries out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The microstructure and phase distribution of the SHS reaction products were characterized by scanning electron microscopy (SEM) and energy dispersive x-ray (EDX), respectively. The results indicate that complete reaction of precursors to yield Al2O3-WSi2 and Al2O3-WB as product composites with clearly separation between Al2O3 and WB.

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Gras, Kaelyn, Jim Luong, Monica Lin, Ronda Gras, and Robert A. Shellie. "Determination of ethylene glycol in lubricants by derivatization static headspace gas chromatography." Analytical Methods 7, no. 13 (2015): 5545–50. http://dx.doi.org/10.1039/c5ay01122a.

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ULBERTH, F., and D. ROUBICEK. "Evaluation of a static headspace gas chromatographic method for the determination of lipid peroxides." Food Chemistry 46, no. 2 (1993): 137–41. http://dx.doi.org/10.1016/0308-8146(93)90026-c.

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Ito, Yusai, Kyoko Ishizuki, Wakana Sekiguchi, Atsuko Tada, Takumi Akiyama, Kyoko Sato, Takeshi Yamazaki, and Hiroshi Akiyama. "Analysis of Residual Solvents in Annatto Extracts Using a Static Headspace Gas Chromatography Method." American Journal of Analytical Chemistry 03, no. 09 (2012): 638–45. http://dx.doi.org/10.4236/ajac.2012.39083.

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Samsuri, Azrul Hisyam, May Yen Ang, and Shean Yeaw Ng. "Optimization of Residual Hexane in Edible Oils Analysis Using Static Headspace Gas Chromatography." International Journal of Analytical Chemistry 2021 (October 29, 2021): 1–6. http://dx.doi.org/10.1155/2021/1941336.

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This study aims to determine the residual hexane in four edible oils in Malaysia using a simple, rapid, and automated method in order to improve the efficiency and productivity of the analysis. Gas chromatography (GC/FID) equipped with a headspace autosampler (HS-20) was used to perform the analysis. Incubation time for each injection was successfully optimized from one hour to 30 minutes (50% reduction) compared to the official AOCS method Ca 3b-87. Out of the four tested edible oils, only the hexane residues detected in sunflower oil exceeded the maximum residue limit (MRL) set by the European Union regulation. Significant difference of the results obtained between large calibration range (0–938 mg kg−1) and small calibration range (0–68 mg kg−1) suggests that there is a need to use a lower standard calibration concentration to avoid misinterpretation of analysis results. Method validation applies to the technical hexane; 2-methylpentane, 3-methylpentane, cyclohexane, and methylcyclopentane, the signal-to-noise (S/N), as well as the limit of quantification (LoQ) values was found to be 218.20, 221.45, 746.37, 97.37 and 0.85, 0.84, 0.25, 1.93 mg kg−1, respectively. Good linearity, repeatability, and low carryover of this method have provided an alternative way to analyze the content of the residual hexane in edible oils in a more efficient manner. Current study might provide a fundamental reference for the improvement of the AOCS official Ca 3b-87 method for determination of hexane residues in fats and oils analysis in the future.

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Zhu, Wenyao, Frank Benkwitz, and Paul A. Kilmartin. "Volatile-Based Prediction of Sauvignon Blanc Quality Gradings with Static Headspace–Gas Chromatography–Ion Mobility Spectrometry (SHS–GC–IMS) and Interpretable Machine Learning Techniques." Journal of Agricultural and Food Chemistry 69, no. 10 (March 4, 2021): 3255–65. http://dx.doi.org/10.1021/acs.jafc.0c07899.

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Petrović, Goran M., Jelena G. Stamenković, Olga P. Jovanović, and Gordana S. Stojanović. "Chemical Compositions of the Essential Oils and Headspace Volatiles of Seseli peucedanoides Plant Parts." Natural Product Communications 14, no. 5 (May 2019): 1934578X1985069. http://dx.doi.org/10.1177/1934578x19850691.

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The chemical compositions of the essential oils of Seseli peucedanoides (M.Bieb.) Koso-Pol. inflorescences and leaves, isolated by hydrodistillation, and headspace volatiles, obtained by the static headspace method, were analyzed in detail by gas chromatography (GC) and GC/mass spectrometry (MS). In total, 74 constituents were identified, representing more than 98% of the observed GC peaks. The number of identified essential oil components obtained from the inflorescences was 63 while for the leaf essential oil it was 46. A much smaller number of compounds, 26 for inflorescences and 21 for leaves, were detected in the headspace samples. In both essential oils the most abundant compounds were the same, ( E)-caryophyllene and germacrene D, only in different proportions. The main components in the headspace specimens were α-pinene and ( E)-β-ocimene with ( E)-caryophyllene and ( Z)-3-hexen-1-ol also determined in significant percentages. The major class of compounds identified in the investigated essential oils was hydrocarbon sesquiterpenes with a share of over 80%, while the most dominant class of the headspace volatiles was hydrocarbon monoterpenes, which contribute slightly less than 80% of the total.

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B'Hymer, Clayton. "Static headspace gas chromatographic method for the determination of residual solvents in vigabatrin drug substance." Journal of Chromatography A 438 (January 1988): 103–7. http://dx.doi.org/10.1016/s0021-9673(00)90238-3.

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ANG, C. Y. W., and F. LIU. "STATIC HEADSPACE CAPILLARY GC METHOD FOR DETERMINING CHANGES OF VOLATILES FROM HEATED CHICKEN BREAST MEAT." Journal of Muscle Foods 7, no. 1 (March 1996): 131–38. http://dx.doi.org/10.1111/j.1745-4573.1996.tb00591.x.

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46

Cheng, Chang, Shaorong Liu, Bradford J. Mueller, and Zimeng Yan. "A generic static headspace gas chromatography method for determination of residual solvents in drug substance." Journal of Chromatography A 1217, no. 41 (October 2010): 6413–21. http://dx.doi.org/10.1016/j.chroma.2010.08.016.

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47

Lee, Sang, Gil-Ok Shin, Kyung Park, Pahn-Shick Chang, and Young-Suk Kim. "Determination of Odor Release in Hydrocolloid Model Systems Containing Original or Carboxylated Cellulose at Different pH Values Using Static Headspace Gas Chromatographic (SHS-GC) Analysis." Sensors 13, no. 3 (February 27, 2013): 2818–29. http://dx.doi.org/10.3390/s130302818.

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Le Roy, Sarah, Catherine Fillonneau, Benoist Schaal, Carole Prost, and Angélique Villière. "Comparative Investigation of Conventional and Innovative Headspace Extraction Methods to Explore the Volatile Content of Human Milk." Molecules 27, no. 16 (August 20, 2022): 5299. http://dx.doi.org/10.3390/molecules27165299.

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The odor of human milk induces search-like movements and oral activation in newborns, which increases their chances of taking advantage of milk intake and benefits. However, the underlying volatile fraction of human milk remains understudied. This study aimed to devise a simple method to extract a wide range of volatile compounds from small-volume human milk samples. Headspace solid phase micro-extraction (HS-SPME) with a Car/PDMS fiber and dynamic headspace extraction (D-HS) with a Tenax or a trilayer sorbent were tested because of their selective affinity for volatiles. Then, innovative variations of these methods were developed to combine their respective advantages in a one-step extraction: Static headspace with multiple SPME fibers (S-HS-MultiSPME), Dynamic headspace with multiple SPME fibers (D-HS-MultiSPME) and dynamic headspace with multiple SPME fibers and Tenax (D-HS-MultiSPME/Tenax). The extracts were analyzed by gas chromatography coupled with mass spectrometric and flame ionization detection. The relative performances of these methods were compared based on qualitative and semi-quantitative analyses of the chromatograms. The D-HS technique showed good sensitivity for most compounds, whereas HS-SPME favored the extraction of acids. The D-HS-MultiSPME/Tenax identified more than 60 compounds from human milk (some for the first time) and evidence of individual singularities. This method that can be applied to volatilome analysis of any biological fluid should further our understanding of human milk odor.

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Sathaporn, Taschaporn, and Sutham Niyomwas. "Optimization of Rare Earth Dope on MAl₂O₄ (M = Ba, Sr) by Self-Propagating High Temperature Synthesis." Advanced Materials Research 488-489 (March 2012): 442–46. http://dx.doi.org/10.4028/www.scientific.net/amr.488-489.442.

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The Eu2+ doped barium aluminate (BaAl2O4:Eu2+) and strontium aluminate (SrAl2O4:Eu2+) with high brightness were synthesized by self-propagating high temperature synthesis (SHS) method. The influence of doping rare earth ions (Eu2+) on the luminescence of MAl2O4:Eu2+ were described in this study. The reactions were carried out in a SHS reactor under static argon gas at a pressure of 0.5 MPa. The morphologies and the phase structures of the products have been characterized by X-ray diffraction (XRD) and scanning electron microscope technique (SEM). The emission spectra of the products have been measured by an Ocean optics spectrometer at room temperature. Broad band UV excited luminescence was observed for BaAl2O4:Eu2+ and SrAl2O4:Eu2+ in the green region peak at λmax = 501 nm and 523 nm, respectively. The optimum Eu2+ doping ratio were 10.5 mol% and 6 mol% for BaAl2O4:Eu2+ and SrAl2O4:Eu2+, respectively

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Shteinberg, A. S., and A. A. Berlin. "Use of Electrothermal Explosion and Electro-Thermal Analyser (ETA-100) for the Study the Kinetics of Fast High-Temperature Reactions in SHS-Ceramic Systems." Advances in Science and Technology 63 (October 2010): 203–12. http://dx.doi.org/10.4028/www.scientific.net/ast.63.203.

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Due to the lack of specialty kinetic methods and instruments, the kinetics of fast hightemperature reactions SHS-ceramic systems has not been adequately studied. Recently, we have developed a number of methods of so-called non-isothermal kinetics (NIK) and designed instruments allowing one to obtain information about reactions of ceramic systems in a wide range of practically important temperatures and rates. The use of one of the NIK-methods (called electrothermal analysis based on the phenomena of electro thermal explosion) allows one to study kinetics of SHS of some ceramic materials characterized by the total reaction time ~ 10 μs. In ETE, both samples pressed from reagents powders or cylindrical samples made from tightly rolled foils were studied. The joule heating was accompanied by high-speed scanning of the non-stationary temperature field on its surface. Description and technical characteristics of the specialty device electrothermoanalyzer ETA-100 manufactured by ALOFT are given. Kinetic parameters of fast EM reactions for the temperatures up to 3600 K can be measured by ETE method using ETA-100. New kinetic data for fast high-temperature gasless SHS yielding individual and composite materials (including refractory carbides and borides of transition metals, silicon and boron carbides, some refractory oxides and hard alloys) are presented. At high-speed impact of the samples, the reaction rate constants were found to exceed the combustion rate constants (measured by ETA-100) by many orders of magnitude. It was concluded that the kinetic mechanisms of the corresponding fast reactions in the static conditions and under the impact are dramatically different. It was shown that SHS in ETE mode has a significant potential as a modern practical method to be used for welding of refractory and dissimilar materials, production of coarse superabrasives, etc.

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Journal articles on the topic 'Static headspace method (SHS)'

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