Статті в журналах: "Masse spectrometry"

1

Zoppi, Ugo. "Radiocarbon AMS Data Analysis: From Measured Isotopic Ratios to 14C Concentrations." Radiocarbon 52, no. 1 (2010): 165–70. http://dx.doi.org/10.1017/s0033822200045112.

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Radiocarbon accelerator mass spectrometry (AMS) measurements are always carried out relative to internationally accepted standards with known 14C activities. The determination of accurate 14C concentrations relies on the fact that standards and unknown samples must be measured under the same conditions. When this is not the case, data reduction is either performed by splitting the collected data set into subsets with consistent measurement conditions or by applying correction factors.This paper introduces a mathematical framework that exploits the intrinsic variability of an AMS system by combining arbitrary measurement parameters into a normalization function. This novel approach allows the en-masse reduction of large data sets by providing individual normalization factors for each data point. Both general features and practicalities necessary for its efficient application are discussed.

2

Helena Pereira, Maria, Luiz de Castro, and Ricardo Michel. "Investigating Molecular Masses Formed during the Heat Treatment of Petroleum Pitches by Mass Spectrometry." Chemistry & Chemical Technology 7, no. 2 (June 10, 2013): 131–39. http://dx.doi.org/10.23939/chcht07.02.131.

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3

Antonation, Kym, Dobryan Tracz, Ashley Dreger, and Cindi Corbett. "Identification des bactéries à cote de sécurité élevée, basée sur la spectrométrie de masse à temps de vol après désorption/ionisation laser assistée par matrice : considérations pour les utilisateurs canadiens de Bruker." Relevé des maladies transmissibles au Canada 46, no. 10 (October 1, 2020): 376–82. http://dx.doi.org/10.14745/ccdr.v46i10a04f.

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4

Bieleń, Wojciech, and Marek Janiga. "Spektrometria masowa i analiza izotopowa biomarkerów frakcji nasyconej." Nafta-Gaz 77, no. 8 (August 2021): 512–28. http://dx.doi.org/10.18668/ng.2021.08.02.

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GC-IRMS analysis extends and confirms (or not) the interpretation based on the results of GC-MS analyses. For example, it is very useful in determining the sedimentation environment of organic matter. GC-MS analysis of biomarkers and the results are reliable, but only GC-IRMS studies can confirm it. In this study, the origin of BNH (28,30-bisnorhopane from chemoautotrophic bacteria) and origin of higher carotenoids and their derivatives from Chlorobiaceae or Chromotiaceae bacteria were confirmed through isotopic analyzes. Biomarkers were analyzed using the GC-IRMS and EA-IRMS apparatus. The obtained chromatograms from the IRMS analyses were compared with the archival GC-MS analyses for the same samples in order to identify individual chemical compounds. In addition to the existing methodology of sample preparation for analyses, a non-standard method was also used, consisting in the separation of n-alkanes from branched hydrocarbons. The repeatability of the method was determined on the GC-IRMS and the values of δ13C for selected biomarkers from the saturated fraction were determined. It was found that samples with low biomarker content are not suitable for analysis. On the other hand, too high concentration of the analyte causes an increase of the chromatogram baseline and worse separation of the peaks, which is also a problem. For the crude oils the δ13C values were initially determined for the biomarkers of the saturated fraction from the hopanes group: bisnorhopane (BNH), oleanane, C29 norhopane, C30 hopane, moretane and the C31-C35 homohopane series. Relatively small differences in δ13C values were found between BNH/hopanes and BNH/crude oils, which suggests the same source of origin for all biomarkers (including BNH). Determining biomarkers in the aromatic fraction using the GC-IRMS method was not successful. In the future, a special methodology for preparing samples for carbon isotopic analyses of aromatic fraction will be required.

5

Kim, Hyub, and Byung-Soo Ahn. "The Study on the Composition in Pharmacopunctures of Eight Principles by Gas Chromatography/Mass Spectrometry." Journal of Korean Institute of Herbal Acupuncture 11, no. 3 (September 30, 2008): 79–91. http://dx.doi.org/10.3831/kpi.2008.11.3.079.

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6

Gambier, Dominique, Hélène Valladas, Nadine Tisnérat-Laborde, Maurice Arnold, and Frédérique Bresson. "Datation de vestiges humains présumés du Paléolithique supérieur par la méthode du Carbone 14 en spectrométrie de masse par accélérateur / Accelerator mass spectrometry radiocarbon dates of human remains from Upper Palaeolithic." Paléo 12, no. 1 (2000): 201–12. http://dx.doi.org/10.3406/pal.2000.1602.

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7

Hoenicke, K., H. Fritz, R. Gatermann, and S. Weidemann. "Analysis of furan in different foodstuffs using gas chromatography mass spectrometry." Czech Journal of Food Sciences 22, SI - Chem. Reactions in Foods V (January 1, 2004): S357—S358. http://dx.doi.org/10.17221/10702-cjfs.

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8

Kim, Jin Hyo, Cho-Long Jin, Geun-Hyoung Choi, and Byung-Jun Park. "Sample Preparation Method for Perfluorochemicals with LC-Tandem Mass Spectrometry in Agricultural Water." Korean Journal of Pesticide Science 19, no. 1 (March 31, 2015): 1–4. http://dx.doi.org/10.7585/kjps.2015.19.1.1.

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9

Botek, P., J. Poustka, and J. Hajšlová. "Determination of banned dyes in spices by liquid chromatography−mass spectrometry." Czech Journal of Food Sciences 25, No. 1 (January 7, 2008): 17–24. http://dx.doi.org/10.17221/737-cjfs.

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A simple and rapid multiresidue method for the determination of nine banned synthetic dyes in various spices has been developed. Reversed phase HPLC coupled with mass spectrometry (tandem in time−ion trap mass analyser) was employed for the examination of crude acetonitrile extract acidified with acetic acid. The detection limits of Para Red, Sudan Orange G, Sudan I, Sudan II, Sudan III, Sudan IV, Sudan Red 7B and Rhodamine B were in the range of 0.02−0.1 mg/kg, the recoveries ranged from 75.7−92.3% with repeatability of 0.9−11.3%. Rather worse performance characteristics were obtained with Tropaeolin 000, obviously due to its more polar nature as compared to other dyes involved in this study. In spite of that, the developed method can be used for a reliable control of a wide range of dyes used for illegal colouring of various spices.

10

Decesari, S., J. Allan, C. Plass-Duelmer, B. J. Williams, M. Paglione, M. C. Facchini, C. O'Dowd, et al. "Measurements of the aerosol chemical composition and mixing state in the Po Valley using multiple spectroscopic techniques." Atmospheric Chemistry and Physics 14, no. 22 (November 18, 2014): 12109–32. http://dx.doi.org/10.5194/acp-14-12109-2014.

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Abstract. The use of co-located multiple spectroscopic techniques can provide detailed information on the atmospheric processes regulating aerosol chemical composition and mixing state. So far, field campaigns heavily equipped with aerosol mass spectrometers have been carried out mainly in large conurbations and in areas directly affected by their outflow, whereas lesser efforts have been dedicated to continental areas characterised by a less dense urbanisation. We present here the results obtained at a background site in the Po Valley, Italy, in summer 2009. For the first time in Europe, six state-of-the-art spectrometric techniques were used in parallel: aerosol time-of-flight mass spectrometer (ATOFMS), two aerosol mass spectrometers (high-resolution time-of-flight aerosol mass spectrometer – HR-ToF-AMS and soot particle aerosol mass spectrometer – SP-AMS), thermal desorption aerosol gas chromatography (TAG), chemical ionisation mass spectrometry (CIMS) and (offline) proton nuclear magnetic resonance (1H-NMR) spectroscopy. The results indicate that, under high-pressure conditions, atmospheric stratification at night and early morning hours led to the accumulation of aerosols produced by anthropogenic sources distributed over the Po Valley plain. Such aerosols include primary components such as black carbon (BC), secondary semivolatile compounds such as ammonium nitrate and amines and a class of monocarboxylic acids which correspond to the AMS cooking organic aerosol (COA) already identified in urban areas. In daytime, the entrainment of aged air masses in the mixing layer is responsible for the accumulation of low-volatility oxygenated organic aerosol (LV-OOA) and also for the recycling of non-volatile primary species such as black carbon. According to organic aerosol source apportionment, anthropogenic aerosols accumulating in the lower layers overnight accounted for 38% of organic aerosol mass on average, another 21% was accounted for by aerosols recirculated in residual layers but still originating in northern Italy, while a substantial fraction (41%) was due to the most aged aerosols imported from transalpine areas. The different meteorological regimes also affected the BC mixing state: in periods of enhanced stagnation and recirculation of pollutants, the number fraction of the BC-containing particles determined by ATOFMS was 75% of the total, while in the days of enhanced ventilation of the planetary boundary layer (PBL), such fraction was significantly lower (50%) because of the relative greater influence of non-BC-containing aerosol local sources in the Po Valley. Overall, a full internal mixing between BC and the non-refractory aerosol chemical components was not observed during the experiment in this environment.

11

Sarajlija, H., N. Čukelj, G. Novotni D Mršić, M. Brnčić, and D. Ćurić. "Preparation of flaxseed for lignan determination by gas chromatography–mass spectrometry method." Czech Journal of Food Sciences 30, No. 1 (January 30, 2012): 45–52. http://dx.doi.org/10.17221/107/2010-cjfs.

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Since 1980s, several methods for the determination of lignans in food samples have been developed depending on the types of lignans and foods analysed, but mostly on flaxseed as a reference food. In this work, specific steps in flaxseed preparation for lignan secoisolariciresinol analysis by gas chromatography-mass spectrometry method were examined. Ethanol extraction of lignan from defatted and non-defatted flaxseed before acid hydrolysis yielded significantly lower concentrations (5172 ± 49 μg/g; 5159 ± 83 μg/g, respectively), when compared to the direct acid hydrolysis (8566 ± 169 μg/g; 8571 ± 192 μg/g, respectively). In the analysed samples of defatted and dried flaxseed, no significant difference in lignan content was observed when compared to non-defatted flaxseed samples.  

12

Sonn, Brandon Joseph, and Andrew Monte. "4521 Collecting, Interpreting and Utilizing Retrospective Clinical Data from Data Warehouses." Journal of Clinical and Translational Science 4, s1 (June 2020): 46–47. http://dx.doi.org/10.1017/cts.2020.172.

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OBJECTIVES/GOALS: Utilizing clinical electronic health record (eHR) data pulled en masse from data warehouses provides unique challenges when applying it to retrospective studies. Use of this data in conjunction with metabolomic and genomic results to predict response to lisinopril or ondansetron has been completed. METHODS/STUDY POPULATION: Study population consists of >2000 subjects recruited from the Emergency Medicine Specimen Bank at University of Colorado Denver (UCD). All patients presenting to the emergency department are approached to participate which significantly increases demographic diversity of our study populations. Clinical data is pulled from Health Data Compass (data warehouse at UCD that collects all electronic health record (EHR) data to be able to deliver de-identified). Effectiveness of lisinopril and ondansetron were investigated using metabolomic data collected via ultra-high performance liquid chromatography mass spectrometry and genomic data from Illumina chip technology to find relevant correlations. RESULTS/ANTICIPATED RESULTS: Obtaining retrospective clinical data from data warehouses comes with significant challenges to be addressed. Verifying all clinical variables from patient EHRs is a crucial step that requires extensive quality control steps. As well, ensuring data validity, appropriateness of data points pulled as relate to the study criteria and identifying alternate EHR data points is needed. Chart review is a critical step necessary to surmount these challenges. Additionally, use of retrospective EHR data often necessitates the development of novel definitions of clinical effectiveness that can be abstracted from the EHR– such as how to determine decrease in nausea without a visual analogue scale. DISCUSSION/SIGNIFICANCE OF IMPACT: Utilizing data warehouses to deliver EHR data provides a valuable tool for completing retrospective precision medicine projects. The validation of definitions for clinical outcomes identifiable retrospectively are necessary and provide novel guidance for future studies.

13

Yang, Shangbin, Lihui Xu, and Haifeng Wu. "Rapid Genotyping of SNPs Influencing Warfarin Drug Response by SELDI-TOF Mass Spectrometry." Blood 112, no. 11 (November 16, 2008): 4053. http://dx.doi.org/10.1182/blood.v112.11.4053.4053.

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Abstract The anticoagulant drug Warfarin exhibits significant inter-individual variability in dosing requirements. Different responses to Warfarin therapy are partly attributed to the single nucleotide polymorphisms (SNPs) that influence either Warfarin drug action (VKORC1) or drug metabolism (CYP2C9). Rapid genotyping of these SNPs is essential for clinicians to choose appropriate initial doses in order to quickly achieve anticoagulation effects and to prevent the complications associated with Warfarin overdoses. In this study, we explore the utility of surface-enhanced laser desorption and ionization time-of- flight (SELDI-TOF) mass spectrometry in the rapid genotyping of SNPs that control Warfarin drug sensitivity. The DNA containing the targeted SNPs is first amplified by polymerase chain reactions and then underwent the single base extension to generate specific SNP product. Afterwards, genetic variants displaying different masses are bound to Q10 anionic proteinChips and genotyped using a SELDI-TOF mass spectrometer in a multiplexed fashion. SELDI-TOF mass spectrometer offers a unique property of on-chip sample enrichment and clean-ups. Therefore, this genotype method eliminated many tedious experimental steps, such as sample desalting and concentrating, that are required prior to detection by standard mass spectrometers. The turnaround time for genotyping three known Warfarin sensitivity SNPs, CYP2C9*2, CYP2C9*3, VKORC1, is less than five hours. The analytical accuracy of genotyping detected by SELDI mass spectrometer has been confirmed by DNA sequencing. In summary, we have devised a novel multiplex genotyping method using a SELDI-TOF mass spectrometer. This test is fast, accurate, and therefore provides a superb clinical laboratory platform to promote the personalized health care in Warfarin therapy.

14

Alimzhanova, M., and D. Makhayeva. "Identification of flavonoids in plant samples by gas chromatography-mass spectrometry with pre-derivatization." International Journal of Biology and Chemistry 9, no. 1 (2016): 46–51. http://dx.doi.org/10.26577/2218-7979-2016-9-1-46-51.

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15

Weinbruch, Stephan, Sigmar Specht, and Herbert Palme. "Determination of Fe, Mn, Ni and Sc in olivine by secondary ion mass spectrometry." European Journal of Mineralogy 5, no. 1 (March 4, 1993): 37–42. http://dx.doi.org/10.1127/ejm/5/1/0037.

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16

Aoyama, Takafumi, Koki Okazaki, Chikara Ito, Hideki Harano, Kenichi Watanabe, and Tetsuo Iguchi. "ICONE15-10323 DEVELOPMENT OF SODIUM LEAK DETECTION TECHNOLOGY USING LASER RESONANCE IONIZATION MASS SPECTROMETRY." Proceedings of the International Conference on Nuclear Engineering (ICONE) 2007.15 (2007): _ICONE1510. http://dx.doi.org/10.1299/jsmeicone.2007.15._icone1510_163.

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17

Al-Beloushi, Ahmad, Ayman Elbehiry, and Eman Marzouk. "Mass Spectrometry Technology and qPCR for Detection of Enterococcus faecalis in Diabetic Foot Patients." Journal of Pure and Applied Microbiology 12, no. 4 (December 30, 2018): 1743–53. http://dx.doi.org/10.22207/jpam.12.4.07.

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18

Persinger, Jared D., Geoffrey C. Hoops, and Michael J. Samide. "Mass Spectrometry for the Masses." Journal of Chemical Education 81, no. 8 (August 2004): 1169. http://dx.doi.org/10.1021/ed081p1169.

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19

Mbaegbu, Makuachukwu F., Puspa L. Adhikari, Ipsita Gupta, and Mathew Rowe. "Mass Spectrometric Calibration Procedure for Real-Time Detection of Lighter Hydrocarbons." Energies 14, no. 8 (April 10, 2021): 2123. http://dx.doi.org/10.3390/en14082123.

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Determining gas compositions from live well fluids on a drilling rig is critical for real time formation evaluation. Development and utilization of a reliable mass spectrometric method to accurately characterize these live well fluids are always challenging due to lack of a robust and effectively selective instrument and procedure. The methods currently utilized need better calibration for the characterization of light hydrocarbons (C1–C6) at lower concentrations. The primary goal of this research is to develop and optimize a powerful and reliable analytical method to characterize live well fluid using a quadruple mass spectrometer (MS). The mass spectrometers currently being used in the field have issues with detection, spectra deconvolution, and quantification of analytes at lower concentrations (10–500 ppm), particularly for the lighter (<30 m/z) hydrocarbons. The objectives of the present study are thus to identify the detection issues, develop and optimize a better method, calibrate and QA/QC the MS, and validate the MS method in lab settings. In this study, we used two mass spectrometers to develop a selective and precise method to quantitatively analyze low level lighter analytes (C1–C6 hydrocarbons) with masses <75 m/z at concentrations 10–500 ppm. Our results suggest that proper mass selection like using base peaks with m/z 15, 26, 41, 43, 73, and 87, respectively, for methane, ethane, propane, butane, pentane, and hexane can help detect and accurately quantify hydrocarbons from gas streams. This optimized method in quadrupole mass spectrometer (QMS) will be invaluable for early characterization of the fluid components from a live hydrocarbon well in the field in real time.

20

Tateo, F., M. Bononi, and F. Gallone. "Rapid detection of dimethyl yellow dye in curry by liquid chromatography-electrospray-tandem mass spectrometry." Czech Journal of Food Sciences 28, No. 5 (October 14, 2010): 427–32. http://dx.doi.org/10.17221/135/2009-cjfs.

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An accurate and rapid method, was devised for the identification and quantitation of dimethyl yellow dye in curry, based on liquid chromatography-tandem mass spectrometry interfaced with electrospray. Mass spectral acquisition was done in positive ion mode applying two fragmentation transitions to provide a high degree of selectivity. The extraction system provided a very high recovery (100.0% to 105.8%) and good results were obtained for the limit of detection (5 μg/kg) and limit of quantitation (16 μg/kg). The applicability of the method to identifing and quantifing the unauthorised dimethyl yellow dye in curry was demonstrated.

21

Hussain, Malik Aabid, and Varsha Nitin Nathar. "Phytochemical Profiling of Ruta graveolens L. a Vital Medicinal Plant Using Gas Chromatography-Mass Spectrometry." SSR Institute of International Journal of Life Sciences 6, no. 3 (May 2020): 2536–43. http://dx.doi.org/10.21276/ssr-iijls.2020.6.3.2.

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22

Huang, Ronald. "Application of Liquid Chromatography-Mass Spectrometry-Based Metabolomics in Cell Culture, Drug Study, and Diseases." International Journal of Bioscience, Biochemistry and Bioinformatics 11, no. 2 (April 2021): 34–39. http://dx.doi.org/10.17706/ijbbb.2021.11.2.34-39.

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23

Kermani, Nazanin Zounemat, Xian Yang, Yike Guo, James McKenzie, and Zoltan Takats. "A Bi-directional Hierarchical Clustering (BHC) for Peak Matching of Large Mass Spectrometry Data Sets." International Journal of Machine Learning and Computing 11, no. 6 (November 2021): 373–79. http://dx.doi.org/10.18178/ijmlc.2021.11.6.1064.

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24

Lee, Yong-Cheol, Bog-Soon Kim, Eun-Sun Yun, Sung-Dan Kim, Min-Su Chang, Young-Ae Park, Young Shin, Sun-Ok Jung, Jae-In Lee, and Young-Zoo Chae. "Monitoring of Forbidden Medicines as Adulterants in Dietary Supplements Marketed Online by HPLC and ESI-tandom Mass Spectrometry." Korean Journal of Food Science and Technology 44, no. 2 (April 30, 2012): 148–54. http://dx.doi.org/10.9721/kjfst.2012.44.2.148.

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25

Villegas, Karla, Kimberly Baker-Deadmond, and Pierre F. Neuenschwander. "Mapping of Allosteric Modulator Effects in the Active Site of Factor IXa." Blood 110, no. 11 (November 16, 2007): 2695. http://dx.doi.org/10.1182/blood.v110.11.2695.2695.

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Abstract Activated factor IX (fIXa) is a vitamin K-dependent blood coagulation serine protease involved in propagation of the coagulant response through activation of fX. Maximal enzymatic and procoagulant activity of fIXa requires the presence of several cofactors; one of which is ionic calcium, which is known to bind to a site in the protease domain of fIXa as well as several sites within the light chain Gla domain region. One of the roles of calcium appears to be allosteric modulation of the fIXa active site as evidenced by an increase in enzymatic activity towards small peptidyl substrates. We and others have additionally found that certain small hygroscopic molecules can also enhance fIXa amidolytic activity. The molecular details involved in either of these effects are not well understood. Previous studies by us have shown that a pentapeptide substrate (AGRSL; the reactive site sequence of antithrombin) is hydrolyzed by fIXa in the absence of cofactors or modulators. This hydrolysis is enhanced in the presence of ionic calcium, ethylene glycol or low molecular weight heparin suggesting effects of these molecules on the immediate active site vicinity of fIXa. In order to gain insight into the potential allosteric modulation that each of these effectors may affect in fIXa, we examined the hydrolysis of four peptide libraries based on the AGRSL pentapeptide sequence, in the presence and absence of various fIXa modulators. The four libraries synthesized were XGRSL, AXRSL, AGRXL and AGRSX; where X denotes any of the possible 20 amino acids. Each of these libraries were screened for hydrolysis by fIXa under various conditions with substrates and products being identified en masse using MALDI-TOF mass spectrometry. The results suggest that ionic calcium enhances fIXa reactivity in part by modulation of the S2 subsite in fIXa. In contrast, ethylene glycol enhances fIXa activity via modulation of the S3 subsite and heparin was found to effect the overall active site region.

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Ye, Lambiénou, Désiré Jean Pascal Lompo, Aboubakar Sako, and Hassan Bismarck Nacro. "Evaluation of trace metal content in soils subjected to inputs of solid urban wastes." International Journal of Biological and Chemical Sciences 14, no. 9 (March 25, 2021): 3361–71. http://dx.doi.org/10.4314/ijbcs.v14i9.31.

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Large amounts of solid urban waste (SUW), sometimes containing trace metal (TM), are used to fertilize agricultural soils. The aim of this study was to assess concentrations of TM in peri-urban agricultural soils exposed to SUW inputs around Bobo-Dioulasso. Composite samples of fourteen soil profiles (0-20 cm, 20-40 cm and 40-60 cm) were collected in the classified Dindéréso forest in the outskirts of Bobo-Dioulasso. Inductively coupled plasma mass spectrometry (ICP/MS) was used to analyze TM concentrations in the samples. Concentrations of Cd, Cr, Cu, Ni, Pb and Zn varied broadly according to the sampling sites and soil horizons. The maximum concentrations of the analyzed elements in all sites were lower than the limit concentrations. Regardless soil horizons, the pollution index were less than 1, suggesting that the sampled soils were not subject to multiple contaminations of TM. D’importantes quantités de déchets urbains solides (DUS), renfermant parfois des éléments traces métalliques (ETM), sont utilisées pour fertiliser les sols agricoles. Le but de cette étude est d’évaluer les concentrations en ETM des sols péri-urbains de la ville de Bobo-Dioulasso soumis à l’épandage des DUS. Des échantillons composites de sols ont été prélevés, suivant les horizons 0-20 cm, 20-40 cm et 40-60 cm, sur quatorze sites dans la forêt classée de Dindérésso située à la périphérie de la ville de Bobo-Dioulasso. L’analyse des échantillons de sol a été effectuée par spectrométrie de masse avec plasma à couplage inductif (ICP/MS). Les résultats montrent que les concentrations en Cd, Cr, Cu, Ni, Pb et Zn des sols sont très variées. Elles varient en fonction de l’ETM, du site et de l’horizon du sol. Les concentrations des différents ETM dans les sols sont inférieures aux valeurs limites sur tous les sites. L’index de pollution de chaque site est inférieur à 1, quel que soit l’horizon de sol, suggérant ainsi que les sites de la zone ne font pas l’objet d’une contamination multiple de leurs sols par les ETM.

27

Gertsiuk, M. M. "Two-Dimensional Gas Chromatography-Mass Spectrometry to Determine Composition of the Products of Waste Tire Pyrolysis." Science and innovation 10, no. 2 (March 30, 2014): 68–71. http://dx.doi.org/10.15407/scine10.02.068.

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28

Kemmo, S., V. Ollilainen, Lampi A-M, and V. Piironen. "Determination of stigmasterol hydroperoxides using high-performance liquid chromatography-mass spectrometry with atmospheric pressure chemical ionization." Czech Journal of Food Sciences 22, SI - Chem. Reactions in Foods V (January 1, 2004): S144—S146. http://dx.doi.org/10.17221/10639-cjfs.

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A new specific method using high-performance liquid chromatography-mass spectrometry (HPLC-MS) for the detection of stigmasterol hydroperoxides was developed. Hydroperoxides of stigmasterol were obtained by photo-oxidation (90 min) in the presence of methylene blue as a sensitizer. The separation was performed using normal-phase chromatographic conditions. The MS detection was carried out with an ion-trap mass spectrometer using atmospheric pressure chemical ionization (APCI) and positive ion mode. Stigmasterol hydroperoxides were seen to produce no protonated molecular ions [M + H]+ but instead fragments representing loss of one or two water molecules [M – H2O + H]+, [M – 2H2O + H]+, loss of hydrogen peroxide [M – H2O2 + H]+ or loss of hydrogen peroxide and water [M – H2O2 – H2O + H]+. The results showed that positional isomers of hydroperoxides had different fragmentation patterns and relative ion abundances. On the other hand anomeric isomers had more similar fragmentation. As a conclusion the method developed showed to be a useful tool for investigation the oxidation mechanism of sterols.

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Blanco, David R., Julian P. Whitelegge, James N. Miller, and Michael A. Lovett. "Demonstration by Mass Spectrometry that Purified Native Treponema pallidum Rare Outer Membrane Protein 1 (Tromp1) Has a Cleaved Signal Peptide." Journal of Bacteriology 181, no. 16 (August 15, 1999): 5094–98. http://dx.doi.org/10.1128/jb.181.16.5094-5098.1999.

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ABSTRACT Purified native Tromp1 was subjected to mass spectrometric analysis in order to determine conclusively whether this protein possesses a cleaved or uncleaved signal peptide. The molecular masses of Tromp1, three Treponema pallidum lipoproteins, and a bovine serum albumin (BSA) control were determined by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. The molecular masses of all of the T. pallidum lipoproteins and BSA were within 0.7% of their respective calculated masses. The molecular mass of Tromp1 was 31,510 Da, which is consistent with a signal-less form of Tromp1, given a calculated mass of unprocessed Tromp1 of 33,571 Da, a difference of 2,061 Da (a 6.5% difference). Purified native Tromp1 was also subjected to MALDI-TOF analysis in comparison to recombinant Tromp1 following cyanogen bromide cleavage, which further confirmed the identity of Tromp1 and showed that native Tromp1 was not degraded at the carboxy terminus. These studies confirm that Tromp1 is processed and does not contain an uncleaved signal peptide as previously reported.

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Rodzik, Agnieszka, Paweł Pomastowski, Viorica Railean-Plugaru, Myroslav Sprynskyy та Bogusław Buszewski. "The Study of Zinc Ions Binding to αS1-, β- and κ-Casein". International Journal of Molecular Sciences 21, № 21 (30 жовтня 2020): 8096. http://dx.doi.org/10.3390/ijms21218096.

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The presented studies focused on the specificity binding of particular casein fractions: αS1-, β- and κ-casein (αS1CN, βCN, κCN), with zinc ions. The binding mechanism was determined by kinetic modeling using results of batch sorption. For this goal, models of zero-order kinetics, pseudo-first-order, pseudo-second-order and Weber–Morris intraparticle diffusion were used. The formation of Zn-αS1CN, Zn-βCN and Zn-κCN complexes was additionally monitored using spectroscopic methods such as Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy, characterizing active functional groups involved in the binding process. Additionally, a mass spectrometry technique—matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)—was used to characterize respective protein fractions and obtained complexes. Spectroscopic and spectrometric studies were carried out both before and after binding the protein with zinc ions. The obtained results showed the difference in Zn-αS1CN, Zn-βCN and Zn-κCN complexes created at separate kinetic stages. On the basis of instrumental studies, a significant influence of acidic (glutamic acid (Glu), aspartic acid (Asp)) and aromatic (tryptophan (Trp), phenylalanine (Phe), tyrosine (Tyr)) amino acids on the formation of metal complexes was proven. In turn, spectrometric studies allowed determining the molecular masses of casein isoforms before and after binding to zinc ions.

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Frański, R., P. Bednarek, D. Siatkowska, P. Wojtaszek, and M. Stobiecki. "Application of mass spectrometry to structural identification of flavonoid monoglycosides isolated from shoot of lupin (Lupinus luteus L.)." Acta Biochimica Polonica 46, no. 2 (June 30, 1999): 459–73. http://dx.doi.org/10.18388/abp.1999_4177.

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Flavonoid glycosides constitute important group of plant secondary metabolites. This class of natural products play significant role in different physiological processes. A new methodological approach where mass spectrometric techniques are applied to structural studies of this class of compounds is presented. Four flavonoid O-monoglycosides and one C-monoglycoside were isolated from green parts of lupin (Lupinus luteus L.). Several different mass spectrometric techniques were applied to structural elucidation of isolated compounds. Desorption ionization mass spectrometry was used for registration of mass spectra of intact and derivatized (permethylated) flavonoid glycosides. In some cases electron impact mass spectra of permethylated compounds were also recorded. Methylated samples after methanolysis and further derivatization of free hydroxyl groups (methylation or acetylation) were analyzed with gas chromatography-mass spectrometry. Combined information drawn from the registered mass spectra enabled us to define molecular mass, structure of aglycones and sugars, and positions of glycosidic bonds on the aglycon. Structures of four flavonoid monoglycosides were elucidated as follows: genistein 7-O-glucoside (1), genistein 4'-O-glucoside (2), 2'-hydroxygenistein 7-O-glucoside (3), and apigenin or genistein 8-C-glycoside (5). For the fourth O-glycoside (4) only molecular mass and masses of the aglycone and sugar were estimated.

32

Ataku, Hanako, Keiko Nishijima, Ayumi Mori, Nobuyuki Fujita, and Kazumi Sasaki. "Differential Identification and Quantification of Cashmere, Sheep and Yak Fibers in Textiles Using Liquid Chromatography/Mass Spectrometry." Sen'i Gakkaishi 71, no. 3 (2015): 141–50. http://dx.doi.org/10.2115/fiber.71.141.

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33

WADA, Yoshinao. "Mass Spectrometry Now in PubMed Citations." Journal of the Mass Spectrometry Society of Japan 62, no. 2 (2014): 13–14. http://dx.doi.org/10.5702/massspec.s14-03.

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34

Nicolescu, Stefan, David H. Cornell, Ulf Södervall, and Hans Odelius. "Secondary ion mass spectrometry analysis of rare earth elements in grandite garnet and other skarn related silicates." European Journal of Mineralogy 10, no. 2 (March 31, 1998): 251–60. http://dx.doi.org/10.1127/ejm/10/2/0251.

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35

Ababutain, Ibtisam. "Antimicrobial Activity and Gas Chromatography-Mass Spectrometry (GC-MS) Analysis of Saudi Arabian Ocimum basilicum Leaves Extracts." Journal of Pure and Applied Microbiology 13, no. 2 (June 30, 2019): 823–33. http://dx.doi.org/10.22207/jpam.13.2.17.

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Wolucka, B. A., and E. De Hoffmann. "Mass spectrometric analysis of prenyl phosphates and their glycosylated forms." Acta Biochimica Polonica 41, no. 3 (September 30, 1994): 345–49. http://dx.doi.org/10.18388/abp.1994_4724.

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Three different mass spectrometric method suitable for the analysis of polyprenyl and dolichyl phosphates and their glycosylated forms are described. Fast atom bombardment mass spectrometry (FAB MS) of glycosyl monophosphopolyprenols produces negative ions characteristic of the intact molecule. Tandem mass spectrometry of (M-H)- anions allows the determination of masses of both glycosyl and lipid moieties. Thus, for example, FAB-MS/MS of a mixture of native glycosyl monophosphopolyprenols isolated from ethambutol-treated Mycobacterium smegmatis enabled us to detect two novel pentosyl monophosphopolyprenols. Two other methods are proposed for the analysis of prenyl phosphates, as these compounds do not produce fragments in FAB-MS/MS at low collisional energy. By Desorption Electron Impact ionization (DEI) an intense (M-H3PO4)+ ion as well as fragments corresponding to the successive loss of isoprene residues (68 Da) can be observed. Alternatively, Desorption Chemical Ionization yields ions corresponding to the loss of 66, 78 and 98 Da (i.e. of a part or the entire phosphate moiety) of a prenyl phosphate molecule. Tandem mass spectrometry of the (M-H-98)- ion gives a series of intense fragments differing by 68 mass units over the whole mass range.

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Tammen, Harald, Thomas Möhring, Markus Kellmann, Andreas Pich, Hans H. Kreipe, and Rüdiger Hess. "Mass Spectrometric Phenotyping of Val34Leu Polymorphism of Blood Coagulation Factor XIII by Differential Peptide Display." Clinical Chemistry 50, no. 3 (March 1, 2004): 545–51. http://dx.doi.org/10.1373/clinchem.2003.028209.

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Abstract Background: The Val34Leu mutation in the activation peptide of factor XIII (FXIIIA) correlates with a lower incidence of myocardial infarction and ischemic stroke but an increased risk for hemorrhagic stroke. We describe mass spectrometric detection of the activation peptide variants in human serum. Methods: We used differential peptide display (DPD) to compare comprehensive peptide maps from pairs of serum samples from healthy volunteers. Peptides were separated by liquid chromatography, and fractions were subjected to mass spectrometry. Mass spectra of all fractions were combined, giving a peptide map representing a two-dimensional display of peptide masses. After comparison of peptide mass maps, peptides that differentiated FXIIIA phenotypes were identified by mass spectrometry. Results: Val34Leu polymorphisms of the activation peptide of FXIIIA were identified in 20 serum samples from 10 volunteers by DPD, and their sequences were confirmed by nanoelectrospray-ionization quadrupole time-of-flight mass spectrometry. Analysis of three (V34V, V34L, and L34L) phenotypes was confirmed by allele-specific genotypic analysis in all (n = 10) volunteers. Conclusion: DPD provides a simple and easy-to-use phenotype assay with advantages over PCR-based assays in being faster and directly analyzing the compound of interest.

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Boidron, Jean-Noël, Pascal Chatonnet, and Monique Pons. "Influence du bois sur certaines substances odorantes des vins." OENO One 22, no. 4 (December 31, 1988): 275. http://dx.doi.org/10.20870/oeno-one.1988.22.4.1263.

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L'élevage des vins en barriques modifie profondément leur expression aromatique.L'étude par chromatographie en phase gazeuse et spectrométrie de masse permet d'identifier plusieurs substances volatiles appartenant à la fraction phénolique des arômes.Les vins rouges présentent naturellement une composition complexe en phénols volatils alors que celle des vins blancs est plus simple. L'élevage sous bois entraîne une augmentation notable des phénols déjà présents ainsi que l'apparition de molécules spécifiques au bois dechêne brûlé.L'interaction des levures et des bactéries avec le bois est mise en évidence.Les vins rouges se caractérisent par une présence parfois abondante d'éthyl phénols, les vins blancs qui ne subissent pas la fermentation malolactique s'en différencient par l'abondancede vinyl phénols.L'étude sensorielle de chaque substance permet de démontrer le rôle négligeable de certaines : furfural, méthyl-5-furfural, alcool furfurylique et le rôle exceptionnel joué par d'autres : cis et trans β-méthyl-γ-octalactone, vanilline et dans certains cas éthyl-4-phénol et éthyl-4-gaïacol.+++Wood storage of wines changes profondly their aromatic expression.Several volatile substances from wines and oak woods phenolic fraction of aroma are identified by gas chromatography and mass spectrometry. Wood storage increases natural phenols concentration. Simultaneously specific burned wood molecules appear.Yeast and bacterial interaction with wood is demonstrated. Ethyl phenols are characteristic of red wines and vinyl phenols of white wines without malolactic fermentation.The sensorial analysis of each substance demonstrates the negligible intervention in wine aroma of furfural, 5-methyl-furfural, and furfuryl alcohol, and the important participation of cis and trans β-methyl-γ-octalactone, vanilin 4-ethyl-phenol and 4-ethyl gaïacol.

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Koudelka, Štěpán, Tereza Gelbíčová, Markéta Procházková, and Renáta Karpíšková. "Lineage and serotype identification of Listeria monocytogenes by matrix-assisted laser desorption ionization-time of flight mass spectrometry." Czech Journal of Food Sciences 36, No. 6 (January 7, 2019): 452–58. http://dx.doi.org/10.17221/87/2018-cjfs.

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The identification of Listeria species, lineages and serotypes remains a crucial issue not only in epidemic surveys, but also in monitoring of the diversity of bacteria in the food chain. The aim of this study was identification of L. monocytogenes strains at lineage and serotype level using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The performance of MALDI-TOF MS was tested to identify L. monocytogenes into two lineages (I and II) and four serotypes (1/2a, 1/2b, 1/2c and 4b) the most commonly found in humans and food. Total of 227 L. monocytogenes strains from different sources were subjected to the study. Some of strains (112) were used for main spectrum profile (MSP) library creation. Other strains of interest (115) were then correctly identified on the lineage level comparing with the library by MALDI-TOF MS analysis using Biotyper (90%) and ClinPro Tools (100%) software. The serotype identification with 55.7% (Biotyper) and 67.8% (ClinPro Tools) accuracy is rather a proof that under given conditions the method has not big potential to be used for serotyping. However, MALDI-TOF MS has a potential to identify lineages of L. monocytogenes of food and human origin.

40

Lee, Choon Geun, Joo Won Kim, Jhulee Park, Yong Il Park, You Jin Hwang, and Jae Kweon Park. "Determination of Mode of Chitosanase Action by Matrix Associated Laser Desorption Ionization - Time of Flight Mass Spectrometry Analysis." Journal of Chitin and Chitosan 21, no. 2 (June 30, 2016): 100–108. http://dx.doi.org/10.17642/jcc.21.2.5.

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41

Barot, Dr Tushar, and Hardik Brahmbhatt. "Development & Validation of Liquid Chromatography Tandem Mass Spectrometry Assay for Quantification of Quetiapine Fumarate in Human Plasma." Indian Journal of Applied Research 4, no. 8 (October 1, 2011): 586–88. http://dx.doi.org/10.15373/2249555x/august2014/154.

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42

Butta, Hena, Raman Sardana, Ashmita Grover, Leena Mendiratta, Sudha Kansal, and Neerav Goyal. "Identification of filamentous Fungi Isolated from Clinical Specimens by MALDITOF Mass Spectrometry in A Tertiary Health Care Centre." Annals of Pathology and Laboratory Medicine 6, no. 1 (January 20, 2019): A36–41. http://dx.doi.org/10.21276/apalm.2264.

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43

Gómez-Almenar, M. C., and J. A. García-Mesa. "Determination of pesticide residues in olives by liquid extraction surface analysis followed by liquid chromatography/tandem mass spectrometry." Grasas y Aceites 66, no. 2 (April 15, 2015): e078. http://dx.doi.org/10.3989/gya.0828142.

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44

Moskalenko, V. B. "Status and Prospects of the Accelerator Mass Spectrometry Center of the Institu te of Applied Physics of NASU." Science and innovation 10, no. 2 (March 30, 2014): 8–17. http://dx.doi.org/10.15407/scine10.02.08.

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45

Jung, So-Young, Ju-Sung Park, Yeo-Joon Son, Su-Jeong Choi, Yun-Jeong Lee, Mi-Sun Kim, So-Hyun Park, Sang-Me Lee, and Young-Zoo Chae. "Analysis of PAHs (polycyclic aromatic hydrocarbons) in Ground Coffee Using GC-tandem Mass Spectrometry and Estimation of Daily Dose." Korean Journal of Food Science and Technology 43, no. 5 (October 31, 2011): 544–52. http://dx.doi.org/10.9721/kjfst.2011.43.5.544.

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46

CARDONE, FABIO, and ROBERTO MIGNANI. "POSSIBLE OBSERVATION OF TRANSFORMATION OF ELEMENTS IN CAVITATED WATER." International Journal of Modern Physics B 17, no. 03 (January 30, 2003): 307–17. http://dx.doi.org/10.1142/s0217979203015759.

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We carried out two experiments of cavitating water. In the first one, we subjected to cavitation a sample of bidistilled and de-ionized water by means of new type of sonotrode with a very long working time (> 30 minutes). We analyzed the cavitated water by three different procedures (mass atomic absorption, cyclotron spectrometry and mass spectrometry). The analysis was confined to the stable chemical elements. We found relevant changes in the concentrations of the elements in the cavitated sample. In the second experiment, the water was cavitated by a standard sonotrode four times, and the cavitated water after each cavitation run was analyzed by means of a spectrometer in the mass range 210 < M < 270. Evidence was found for an excess of identified masses in the transuranic region. Our results are similar, in many respects, to those obtained by Urutskoev et al. in the experimental study of electric explosion of metal foils in water. A possible connection with the recent Oak Ridge experiment on nuclear fusion induced by cavitation is also hypotesized.

47

Dominguez-Medina, Sergio, Shawn Fostner, Martial Defoort, Marc Sansa, Ann-Kathrin Stark, Mohammad Abdul Halim, Emeline Vernhes, et al. "Neutral mass spectrometry of virus capsids above 100 megadaltons with nanomechanical resonators." Science 362, no. 6417 (November 22, 2018): 918–22. http://dx.doi.org/10.1126/science.aat6457.

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Measurement of the mass of particles in the mega- to gigadalton range is challenging with conventional mass spectrometry. Although this mass range appears optimal for nanomechanical resonators, nanomechanical mass spectrometers often suffer from prohibitive sample loss, extended analysis time, or inadequate resolution. We report on a system architecture combining nebulization of the analytes from solution, their efficient transfer and focusing without relying on electromagnetic fields, and the mass measurements of individual particles using nanomechanical resonator arrays. This system determined the mass distribution of ~30-megadalton polystyrene nanoparticles with high detection efficiency and effectively performed molecular mass measurements of empty or DNA-filled bacteriophage T5 capsids with masses up to 105 megadaltons using less than 1 picomole of sample and with an instrument resolution above 100.

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Kim, Jin Hyo, Jong Min Park, Geun-Hyoung Choi, Yun-Ki Park, Geon-Jae Im, Doo-Ho Kim, and Oh-Kyung Kwon. "Comparison of Liquid Chromatography-Mass/Mass Spectrometry (MS) and Gas Chromatography-MS for Quantitative Analysis of Indole-3-acetic acid and Indole-3-butyric acid from the Concentrated Liquid Fertilizer." Journal of Applied Biological Chemistry 56, no. 1 (March 31, 2013): 53–57. http://dx.doi.org/10.3839/jabc.2013.010.

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49

Jordáková, I., J. Dobiáš, M. Voldich, and J. Poustka. "Determination of vinyl chloride monomer in food contact materials by solid phase microextraction coupled with gas chromatography/mass spectrometry." Czech Journal of Food Sciences 21, No. 1 (November 18, 2011): 13–17. http://dx.doi.org/10.17221/3472-cjfs.

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The present study concerns the optimisation of the headspace solid phase microextraction (HS/SPME) combined with gas chromatography/mass spectrometry (GC/MS) for the vinyl chloride monomer determination. Samples of PVC materials were analysed using the Carboxen/Polydimethylsiloxane (CX/PDMS) 75 µm fibre. For this fibre, the achieved limit of detection was 0.05 µg/kg, and that of quantification 0.17 µg/kg, respectively, with RSD 5%. The levels of VCM found ranged from 0.29 to 0.44 mg/kg, in the case of foil, the VCM content determined was 3.65 mg/kg which means that the maximal limit allowed was exceeded.  

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IWASA, Shuichi, Shigeki OHIGASHI, Toshio KOSAKI, Yukiko SHIMIZU, Kazunori KOMATSUZAKI, Masafumi HASHINO, Hiroshi SAITO, and Takumi YANAIHARA. "19-Hydroxyandrostenedione in Human Ovarian Vein Measured by GC-MS." Folia Endocrinologica Japonica 67, no. 6 (1991): 692–701. http://dx.doi.org/10.1507/endocrine1927.67.6_692.

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