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Journal articles on the topic "MS 2200"
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Haarmann, Axel, and Mathias Buttmann. "MS-Therapien im Kindesalter: Behandeln wir kleine Erwachsene?" DNP - Der Neurologe & Psychiater 20, no. 3 (2019): 27–28. http://dx.doi.org/10.1007/s15202-019-2200-1.
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Peng, Xiyan, Cuihua Du, Zhenyu Wu, Jun Ma, and Xu Zhou. "The stellar metallicity distribution of the Galaxy from the BATC survey." Proceedings of the International Astronomical Union 9, S298 (2013): 432. http://dx.doi.org/10.1017/s1743921313006984.
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AbstractUsing ~2200 BATC main sequence (MS) stars which include SDSS stellar atmospheric parameters, we develop the polynomial photometric calibration method to evaluate the stellar effective temperature and metallicity for BATC data. This calibration method has been applied to about 160 000 MS stars. The mean stellar metallicity smoothly decreases from −0.65 to −0.78 dex in the interval 0.5 < |Z| ≤ 2 kpc. Metallicity distributions in the halo and the thick disk seem invariant with the distance from the Galactic plane.
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Park, Lee, Byeon, et al. "Pharmacokinetic and Metabolism Studies of Monomethyl Auristatin F via Liquid Chromatography-Quadrupole-Time-of-Flight Mass Spectrometry." Molecules 24, no. 15 (2019): 2754. http://dx.doi.org/10.3390/molecules24152754.
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A simple liquid chromatography–quadrupole-time-of-flight–mass spectrometric assay (LC-TOF-MS/MS) has been developed for the evaluation of metabolism and pharmacokinetic (PK) characteristics of monomethyl auristatin F (MMAF) in rat, which is being used as a payload for antibody-drug conjugates. LC-TOF-MS/MS method was qualified for the quantification of MMAF in rat plasma. The calibration curves were acceptable over the concentration range from 3.02 to 2200 ng/mL using quadratic regression. MMAF was stable in various conditions. There were no significant matrix effects between rat and other preclinical species. The PK studies showed that the bioavailability of MMAF was 0% with high clearance. Additionally, the metabolite profiling studies, in vitro/in vivo, were performed. Seven metabolites for MMAF were tentatively identified in liver microsome. The major metabolic pathway was demethylation, which was one of the metabolic pathways predicted by MedChem Designer. Therefore, these results will be helpful to understand the PK, catabolism, and metabolism behavior of MMAF comprehensively when developing antibody-drug conjugates (ADCs) in the future.
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Das, Anath Bandhu, Iswar Chandra Mohanty, Dawanidhi Mahapatra, Suprava Mohanty, and Ashutosh Ray. "Genetic variation of Indian potato (Solanum tuberosum L.) genotypes using chromosomal and RAPD markers." Crop Breeding and Applied Biotechnology 10, no. 3 (2010): 238–46. http://dx.doi.org/10.1590/s1984-70332010000300009.
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Genetic diversity in thirty Indian potatoes were analyzed employing karyotype, genome size and RAPD markers. Chromosome analysis revealed 2n = 4x = 48 except cv. K. Chandramukhi (2n = 4x + 2 = 50). Total genomic chromosome length and chromosome volume varied from 21.14µm in cv. K. Pukhraj to 31.91µm in cv. MS/89-60 and 14.31µm³ in cv. MS/92-1090 to 33.16µm³ in cv. JW-160 respectively. 4C DNA content was significantly varied from 3.640 pg (~891 Mbp) in cv. MS/92-1090 to 11.12 pg (~2747 Mbp) in cv. K. Chandramukhi. RAPD revealed 131 amplified DNA fragments (300 to 2200 bp) with 79 unique bands (7 to 71% polymorphism) among the genotypes. Similarity coefficients (ranged from 0.29 to 0.93) and cluster analysis reflected the expected trends in relationships of the full and half-sib potato genotypes. Genetic distances obtained from a dendrogram could help breeders to choose the diverse parents for a breeding program aimed at varietal improvement.
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Smeds, Annika I., Patrik C. Eklund, and Stefan M. Willför. "Characterization of high-molar-mass fractions in a Scots pine (Pinus sylvestris L.) knotwood ethanol extract." Holzforschung 72, no. 3 (2018): 201–13. http://dx.doi.org/10.1515/hf-2017-0079.
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AbstractThe identification of compounds in Scots pine (Pinus sylvestrisL.) knotwood (KnW), obtained by extracting with hydrophilic organic solvents, has been performed previously almost exclusively by gas chromatography-mass spectrometry (GS-MS) equipped with long GC columns (≥25 m). That means that the molar mass (MM) of the majority of the identified compounds was below 500–600 Da, and the analytical data accounted for only about half of the dry extract weight. In the present work, high-molar-mass (HMM) fractions in a Scots pine KnW-EtOH extract were isolated and chemically characterized by means of several advanced analytical techniques, such as high performance size-exclusion chromatography-evaporative light scattering detector (HPSEC-ELSD), high performance liquid chromatography (HPLC)-electrospray ionization-ion trap-mass spectrometry [(HPLC)ESI-IT-MS], ESI-quadrupole time of flight-mass spectrometry (QTOF-MS), pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), thermally assisted hydrolysis and methylation-gas chromatography-mass spectrometry (THM-GC-MS), nuclear magnetic resonance (NMR) and GC-MS. The results indicate that the MM maxima of the HMM fractions ranged from approximately 500 to 2200 Da, and that the compounds consist mainly of oligomers of hydroxylated resin acids (RAs), especially dehydroabietic acid, but also of fatty acids (FAs), stilbenes and sterols. A large number of RA dimers were tentatively identified in the HMM fractions. However, it remains unknown how the monomer units are linked together, as it was not possible to isolate a RA dimer fraction pure enough for NMR characterization. RA dimers in native KnW have not been identified previously.
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Patterson, Jeffrey, Xiaojian Shi, William Bresette, et al. "A Metabolomic Analysis of the Sex-Dependent Hispanic Paradox." Metabolites 11, no. 8 (2021): 552. http://dx.doi.org/10.3390/metabo11080552.
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In Mexican Americans, metabolic conditions, such as obesity and type 2 diabetes (T2DM), are not necessarily associated with an increase in mortality; this is the so-called Hispanic paradox. In this cross-sectional analysis, we used a metabolomic analysis to look at the mechanisms behind the Hispanic paradox. To do this, we examined dietary intake and body mass index (BMI; kg/m2) in men and women and their effects on serum metabolomic fingerprints in 70 Mexican Americans (26 men, 44 women). Although having different BMI values, the participants had many similar anthropometric and biochemical parameters, such as systolic and diastolic blood pressure, total cholesterol, and LDL cholesterol, which supported the paradox in these subjects. Plasma metabolomic phenotypes were measured using liquid chromatography tandem mass spectrometry (LC-MS/MS). A two-way ANOVA assessing sex, BMI, and the metabolome revealed 23 significant metabolites, such as 2-pyrrolidinone (p = 0.007), TMAO (p = 0.014), 2-aminoadipic acid (p = 0.019), and kynurenine (p = 0.032). Pathway and enrichment analyses discovered several significant metabolic pathways between men and women, including lysine degradation, tyrosine metabolism, and branch-chained amino acid (BCAA) degradation and biosynthesis. A log-transformed OPLS-DA model was employed and demonstrated a difference due to BMI in the metabolomes of both sexes. When stratified for caloric intake (<2200 kcal/d vs. >2200 kcal/d), a separate OPLS-DA model showed clear separation in men, while females remained relatively unchanged. After accounting for caloric intake and BMI status, the female metabolome showed substantial resistance to alteration. Therefore, we provide a better understanding of the Mexican-American metabolome, which may help demonstrate how this population—particularly women—possesses a longer life expectancy despite several comorbidities, and reveal the underlying mechanisms of the Hispanic paradox.
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de Luces Fortes*, Gerson Renan, and Ana Carolina Pereira e Silva. "In Vitro Multiplication of Brazilian Ginseng (Pfaffia spp.) for in Vitro Conservation Purposes." HortScience 39, no. 4 (2004): 753D—753. http://dx.doi.org/10.21273/hortsci.39.4.753d.
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Brazilian ginseng (Pfaffia sp.) is largely known as having anabolic, analgesic, anticancerous, anti-inflammatory, antileukemic properties, and more. Embrapa Genetic Resources and Biotechnology is the major Conservation Center in Brazil. This species could only be stored under in vitro conditions. There are more than two hundred native acessions collected from different locations in the country. So far very few works are found in the literature and there is no specific protocol for in vitro conservation. The aim of this study was to test five different acessions from in vitro collection under one specific nutrient medium. The acessions were catalogued as 2205-12; 2202-04; 2209-11; 2209-10 and 2205-21. One-bud microcutting was inoculated on a MS nutrient medium without growth regulators and added with vitamins, myoinositol (100 mg·L-1), sucrose (30 mg·L-1) and agar (6 mg·L-1). The pH was adjusted to 5.7 before the agar addition. Each treatment was replicated 7 (seven) times and each plot consisted of six test tubes with 5-mL solution. The trial was replicated twice. The evaluations were performed once weekly where the shoot growth was taken along with the number of buds and roots formed. The highest shoot growth were obtained for the acessions 2205-12 and 2209-10. Acession 2209-11 had an intermediate shoot growth and number of buds, but had the highest number of roots per shoot (4.27) compared to 2.14 and 3.75 for acessions 2205-21 and 2209-10, respectively. The highest rate of multiplication was achieved for acessions 2205-12 (4.49) and 2202-04 (4.46) as compared to 3.60 for acession 2205-21. It was clearly shown that acession 2205-21 is a recalcitrant one as in vitro multiplication is concerned. All the acessions rooted in this medium.
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Berendt, F., T. Froehlich, M. Boelhauve, T. Guengoer, E. Wolf, and G. J. Arnold. "239 OOCYTE MATURATION IN VITRO: PROTEOME ALTERATIONS ANALYZED BY ULTRA-SENSITIVE FLUOROCHROME LABELING AND NANO-ESI-MS-MS." Reproduction, Fertility and Development 20, no. 1 (2008): 199. http://dx.doi.org/10.1071/rdv20n1ab239.
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In mammals, oocytes are arrested in the diplotene stage of the first prophase until the beginning of the estrous cycle. Directly before ovulation, the oocyte completes the first meiotic division and progresses to metaphase II. This process is mimicked by oocyte maturation in vitro, which is critical in assisted reproduction techniques in humans and animals. A sensitive 2-dimensional (2D) difference gel electrophoresis (DIGE) saturation labeling approach including an internal pooled standard was used for quantitative proteome profiling of immature v. in vitro-matured bovine oocytes. A mixture of 0.25 µg of oocyte sample and 0.25 µg of the internal pooled standard was separated on each analytical 2D gel, corresponding to the protein content of approximately five oocytes. In total, the study comprised 48 2D gel images representing 24 DIGE experiments [6 independent samples � 2 gels per stage (immature/mature) � 2 pH gradients]. DeCyder differential in-gel analysis (DIA; Amersham Biosciences, Piscataway, NJ, USA) detected 2244 spots (SD = 100) in pH 4–7 images, and 1291 spots (SD = 65) in pH 6–9 images. In total, 38 spots with different intensity were detected (abundance ratio ≥2; Student's t-test, P ≤ 0.01). Differently abundant spots were identified by nano-LC-MS/MS analysis of matched spots in a preparative gel of saturation-labeled protein extract from 2200 immature oocytes. Ten spots could be unambiguously identified and comprised, e.g., interesting proteins such as clusterin, 14-3-3 ε, redox enzymes, and new polymorphic forms of glutathione-S-transferases. Clusterin is suggested to interact with components of the complement membrane attack complex, and 14-3-3 ε is a mediator of the activation of the maturation promoting factor, a key enzyme of the meiosis. Our study demonstrates the feasibility of differential oocyte proteomics using saturation labeling. Several of the proteins identified in this study are already known to play an important role in oocyte maturation, which reflects the relevance and reliability of our approach. Furthermore, we found proteins which are so far unknown in the context of oocyte development. A more detailed knowledge of the role of these candidates during oocyte maturation may help to optimize the in vitro-maturation process in order to increase the rate of successful in vitro fertilization and other assisted reproduction techniques in cattle and other mammals. This work was supported by grant Deutsche Forschungsgemeinschaft (FOR 478, GRK 1029).
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Almeida, Edison Xavier de, Gerzy Ernesto Maraschin, Oscar Emilio Ludtke Harthmann, Henrique Mendonça Nunes Ribeiro Filho, and Elena Apesteguia Setelich. "Oferta de forragem de capim-elefante anão 'Mott' e o rendimento animal." Revista Brasileira de Zootecnia 29, no. 5 (2000): 1288–95. http://dx.doi.org/10.1590/s1516-35982000000500005.
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A pesquisa foi realizada durante as estações de crescimento de 1994/95 e 1995/96 (out./abr.), na Estação Experimental de Ituporanga/EPAGRI - SC, objetivando determinar o potencial de produção animal e as respostas em termos de taxa de acúmulo de matéria seca (MS) e qualidade de forragem e estrutura do perfil de uma pastagem de capim-elefante anão `Mott' (CEAM) submetida a quatro níveis de oferta de forragem (OF). Os níveis reais de FO foram 3,8; 7,5; 10,2 e 14,0 kg de MS de lâminas verdes (MSLV)/100 kg de PV/dia, num delineamento em blocos casualizados completos com duas repetições e três novilhos (8 a 10 meses) por potreiro, sob pastejo contínuo e uso da técnica "put-and-take". As OF determinaram resíduos médios de MSLV (RMSLV) de 722; 1537; 2332; e 2542 kg/ha, respectivamente. Ofertas de forragem crescentes condicionaram acréscimos na taxa de acúmulo de MSLV/ha/dia e na densidade da forragem. A OF de 11,3 kg de MSLV/100 kg de PV/dia (RMSLV de 2200 kg/ha) maximiza o desempenho animal com 1,06 kg/dia de ganho médio diário e assegura ganho/ha de 5,6 kg/dia, em condição de sustentabilidade da pastagem de CEAM, em pastejo contínuo.
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Nelson, Robert E., Stefan K. Grebe, Dennis J. O’Kane, and Ravinder J. Singh. "Liquid Chromatography–Tandem Mass Spectrometry Assay for Simultaneous Measurement of Estradiol and Estrone in Human Plasma." Clinical Chemistry 50, no. 2 (2004): 373–84. http://dx.doi.org/10.1373/clinchem.2003.025478.
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Abstract Background: Estradiol (E2) and estrone (E1) measurements form an integral part of the assessment of female reproductive function and have expanding roles in other fields. However, many E1 and E2 immunoassays have limited functional sensitivity, suffer from cross-reactivity, and display poor intermethod agreement. To overcome these problems, we developed a sensitive liquid chromatography–tandem mass spectrometry (LC-MS/MS) assay for the simultaneous measurement of E1 and E2. Methods: After dansyl chloride derivatization, samples were separated by fast gradient chromatography and injected into a tandem mass spectrometer after formation of positive ions with atmospheric pressure chemical ionization. The limits of detection and quantification, recovery, linearity, precision, and reference intervals were determined, and performance was compared with several immunoassays. Results: Total run time per sample was 5 min. The multiple-reaction monitoring ion pairs were m/z 506/171 for 3-dansyl-estradiol and m/z 504/171 for 3-dansyl-estrone. The limits of detection for E1 and E2 were 12.9 pmol/L (3.5 ng/L) and 10.3 pmol/L (2.8 ng/L), respectively. Interassay imprecision (CV) was 4–20% (n = 20). The limits of quantification (functional sensitivities) for E1 and E2 were 44.1 pmol/L (11.9 ng/L) and 23.2 pmol/L (6.3 ng/L), respectively. The assay was linear to &gt;2200 pmol/L (∼600 ng/L) for each analyte. Recoveries were 93–108% for E1 and 100–110% for E2. No cross-reactivity was observed. Method comparison with several immunoassays revealed that the latter were inaccurate and prone to interferences at low E1 and E2 concentrations. Conclusions: LC-MS/MS allows rapid, simultaneous, sensitive, and accurate quantification of E1 and E2 in human serum.
Dissertations / Theses on the topic "MS 2200"
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Hernández, Moreno Luis Gustavo Eduardo. "Implementación de una Metodología Analítica para la Cuantificación de Acrilamida en Papas Chips por HPLC MS/MS." Tesis, Universidad de Chile, 2007. http://www.repositorio.uchile.cl/handle/2250/105663.
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Memoria para optar al título de Químico Farmacéutico<br>En el año 2002 la Administración Nacional de Alimentos de Suecia detectó altas
concentraciones de acrilamida que se formaba durante el calentamiento a altas temperaturas de
alimentos ricos en almidón, como las papas fritas, pan, galletas, alimentos extruídos, etc.
La acrilamida es genotóxico y ha sido clasificada como “probable carcinogénico para humanos”
(Grupo 2A) por la Agencia Internacional de Investigación sobre Cáncer IARC, y esta exposición
causa daño al sistema nervioso en seres humanos y animales
Con motivo de este hallazgo, surgió el requerimiento urgente de desarrollar un método analítico
sensible, robusto y de un costo razonable, que pueda cuantificar acrilamida en diferentes
matrices de alimentos con bajos niveles de detección (Mg/Kg).
Durante el desarrollo de esta memoria se implementó en el Centro de Investigación y Desarrollo
en Grasas y Aceites (CIDGRA), Departamento de Ciencia de los Alimentos y Tecnología
Química de la Facultad de Ciencias Químicas y Farmaceúticas de la Universidad de Chile, la
metodología analítica para cuantificar acrilamida por HPLC MS/MS. Se determinó la precisión y
exactitud en el análisis de acrilamida por HPLC MS/MS. Finalmente se aplicó la metodología
para el análisis de papas fritas chips comerciales y elaboradas en el laboratorio dentro del
Proyecto Heatox 506820.
En conclusión se puede decir que se logró una respuesta total a los objetivos planteados siendo
implementado en el Centro de Investigación y Desarrollo en Grasas y Aceites (CIDGRA), la
metodología analítica para la extracción de acrilamida en papas chips y su cuantificación por
HPLC MS/MS. Lo cual abre las puertas, para el comienzo de la investigación, de los alimentos
de consumo habitual en nuestro país y que pudieran contener acrilamida, y así tomar las medidas
necesarias en cuanto a políticas de salud, para el bienestar de nuestra población
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Masters, Barrie James. "A novel calibration strategy for laser ablation ICP-MS." Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/22010.
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Sample introduction by laser ablation has many desirable features: reduction of the time involved in sample pre-analysis processing, avoiding the use of hazardous reagents and reducing the risk of contamination by reagent impurities. It is also possible to produce spatial analytical profiles across small sections of samples. Laser spots of < 10 μm diameter are possible With the latest commercial instrumentation. Additionally, for plasma spectrometry, the presence of molecular species derived from the plasma gases and the solvent vapour results in interferences, particularly for elements with an atomic mass of less than 80. Sampling with a laser removes the need for a solvent. The type of laser used for sampling is an important consideration. Ultraviolet lasers give better coupling between the laser and sample with ablation being mainly photochemical in nature. With infrared lasers, coupling with some samples is inefficient and is generally thermal m nature leading to poor crater definition. Calibration is one of the main difficulties associated with quantitative analysis by laser ablation. The majority of papers associated with the use of lasers for solid sampling give reference to the difficulty of reproducible calibration and in particular the lack of matrix matched standards The most commonly used calibration method to date involves the use of the National Institute of Standards and Technology (NIST) standard reference materials, particularly the 600 series glass standards. The disadvantages associated with these standards are: the analyst has no control over the elemental make up of the standard, they are relatively expensive and most importantly the matrix is fixed and cannot be matched to the sample. This thesis describes a calibration technique based on the ablation of aqueous standards. Water is transparent to the commonly used UV laser wavelengths, 193,248 and 266 nm resulting in poor energy coupling between the laser and the aqueous standard. The addition of a photo-stable chromophore results in modification of the standards absorption coefficient and enables them to mimic the behaviour of solid samples. the benefit of such standards is that they are easy to produce in any analytical laboratory. The elemental and matrix composition can be controlled by the analyst. The standards also offer the advantage of a constantly renewable surface. Initial work involved design and set-up of an optical system and laser to couple the laser with an ICP-MS. Poly( sodium 4-styrene-sulphonate) was identified as a suitable chromophore. The main criteria for the additive being that it absorbed at the excimer laser wavelengths and had an acceptable lifetime to allow adequate analytical data to be generated Investigation into the characteristics of the chromophore including effect of concentration, laser energy and laser frequency were investigated. Calibration and validation of the aqueous calibration technique was demonstrated by comparison with NIST standard reference materials. The absorption coefficient of the aqueous standard was matched with that of the NIST reference material. Both samples were then analysed by ICP-MS. The count rates observed were initially found to be similar for both samples, however the signal for the aqueous standard remained stable but the signal for the NIST glass decreased. This was thought to be due to the laser channelling into the solid sample causing loss of focus. The aqueous standard in effect provides a constantly renewable surface and no loss of focus. An internal standard was used to correct for the differing sensitivities obtained. The final part of the work involved application of the calibration method to two biological matrices: Bone samples from patients with osteoporosis and porcine liver samples. Elemental profiles across the samples are presented which are in general agreement with the expected and certified concentrations.
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Stompe, Annelie. "Sozialisatorische Voraussetzungen von Statuspassagen Jugendlicher auf dem Lande in Ostdeutschland." Doctoral thesis, Humboldt-Universität zu Berlin, Philosophische Fakultät IV, 2002. http://dx.doi.org/10.18452/13833.
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Die Arbeit analysiert den sozioökonomischen Wandel auf dem Lande in Ostdeutschland und seine Folgen für die Sozialisation und die Statuspassagen der Jugendlichen, besonders auf dem Hintergrund der sozialökonomischen Lage ihrer Familien. Gegenstand der Untersuchung ist der Übersetzungsprozess der grundlegenden Transformation der Arbeits- und Lebensverhältnisse auf dem Lande in die familialen und weiteren Sozialisationskontexte von Jugendlichen sowie dessen Niederschlag in ihren Handlungsmustern, Wertorientierungen, Lebensentwürfen und Statuspassagen. Untersucht wurden auf der Basis repräsentativer schriftlicher Befragungen sowie einer Auswahl mündlicher Interviews Jugendliche, die sich am Ende ihrer Normalschulzeit befinden, und deren Eltern. Ihren besonderen Reiz erfährt die Untersuchung durch einen Vergleich zu einer Untersuchung, die Ende der 70er Jahre zu Lebensbedingungen und zur Lebensweise von Schuljugendlichen auf dem Lande in der DDR durchgeführt wurde.<br>This habilitation is examined the radical socioeconomic change in agrarian districts of East Germany and the impact of this modernisation process on the working and living conditions of families, and especially the young people. The study scrutinises the status passage of the young generation (16 to 18 year old school leavers) on the backround of the socioeconomic situation of their families. It takes into account the familial and life world context of the socialisation process and looks at the status passage from school to work as a process of translating the changing social conditions into patterns of value orientation, life course planning, and biography construction. Representative questionings and interviews of the young people and their parents are the empirical basis for this study. The special charm of this research project is the historical comparison with studies on life conditions and ways of life of young people in the GDR during the 70s.
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Albornoz, Huertas Laura. "Estudio químico y metabolómico de los metabolitos secundarios presentes en los líquenes Ramalina celastri, Punctelia rudecta y Sticta especies por HPLC-MS/MS en tándem." Tesis, Universidad de Chile, 2019. http://repositorio.uchile.cl/handle/2250/171102.
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Tesis para optar el Grado de Magíster en Ciencias Químicas<br>Colombia y Chile son países que cuentan con una amplia biodiversidad de líquenes debido a la enorme variedad de ecosistemas que presentan, por lo que surge la necesidad de contribuir y extender el conocimiento de compuestos de líquenes nativos de los mismos; de ahí el presente trabajo se enfocó en el estudio químico de 5 especies liquénicas conocidas como Punctelia rudecta, 2 especies de Ramalina celastri (Chile y Colombia), Sticta lineariloba (Mont.) Nyl y Sticta leucoblepharis. El estudio fue realizado al extracto metanólico de cada una de las especies liquénicas: primero, con el aislamiento y purificación de los extractos de los líquenes empleando técnicas cromatográficas clásicas como Sephadex LH-20, cromatografía en columna (CC), cromatografía en capa fina (CCF), cromatografía en capa preparativa (CCP) y HPLC preparativo, la caracterización e identificación de los metabolitos aislados a partir de métodos espectroscópicos mono y bidimensionales como son 1H-RMN, 13C-RMN, COSY, HMQC y HMBC y; segundo, un estudio basado en UHPLC-Q/Orbitrap/ESI/MS/MS para la caracterizacion e identificación completa de los metabolitos secundarios conocidos y desconocidos de las especies mencionadas. En conjunto, se incorporaron las siguientes especies del género Sticta colectadas en Colombia: S. pseudosylvatica-Co, S. impressula (Nyl.) Zahlbr-Co, S.luteocyphellata-Co, S.ocaniensis-Co) con el propósito de contribuir al escaso conocimiento de los perfiles metabolómicos del género Sticta, Punctelia y Ramalina. El perfil metabolómico fue desarrollado con la comparación de las masas moleculares exactas (obtenidas del espectro de masas de alta resolución (orbitrap MS/MS), tiempos de retención y patrones de fragmentación característicos experimentales con datos reportados en literatura.
A partir de los extractos metanólicos fueron aislados e identificados los siguientes metabolitos secundarios: metil orselinato, ácido orselinico y ácido isolecanórico para P.rudecta; ácido isousnico (un dibenzofurano) en R.celastri-Co; para S.leucoblepharis, peróxido de ergosterol; y en S.lineariloba, ácido 8-metil estictico (depsidona), metil orselinato, derivado del ácido retigérico y ácido 6-hidroxi
norstictico. Por otra parte, usando la técnica de espectrometría de masas en tándem se identificaron por primera vez, 125 metabolitos pertenecientes a las siguientes clases de compuestos: depsidos, depsidonas, depsonas, fenólicos, polisacáridos, ácidos grasos, difenileter, derivado de ácido pulvinico y dibenzofuranos. Los compuestos conocidos incluyen 46 en R. celastri (Co-Ch),7 en P. rudecta, 72 en los extractos metanólicos de Sticta-Ch y Co, además de un total de 51 metabolitos que no fueron identificados ni informados hasta el momento, y podrían ser nuevos según el análisis de los datos. Este estudio demostró que la técnica fue efectiva y precisa para el análisis de los perfiles metabolómicos de los líquenes estudiados y los datos recopilados fueron útiles para el analisis quimiotaxonómico.
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Riquelme, Vilches Sebastián Ariel. "Desarrollo, validación e implementación de una metodología confirmatoria para la identificación y cuantificación simultánea de florfenicol, cloranfenicol y tiafenicol en productos farmacéuticos de uso veterinario por LC-MS/MS." Tesis, Universidad de Chile, 2011. http://repositorio.uchile.cl/handle/2250/105390.
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Memoria para optar al Título de Químico Farmacéutico<br>La utilización de antimicrobianos por parte de la industria del salmón, ha sido en respuesta a la necesidad del control de ataques de patógenos oportunistas dado los sistemas de cultivo intensivos utilizados por esta industria. En este ámbito en Chile, los fenicoles han sido ampliamente usados.
El descubrimiento de los fenicoles surgió de la extracción desde Streptomyces venezuelae de cloranfenicol, posteriormente éste ha sido obtenido de forma sintética. Este descubrimiento llevó consigo el estudio de derivados tales como el tianfenicol y el florfenicol. Según la normativa vigente en Chile y en la Unión Europea, el cloranfenicol es de uso prohibido en animales de consumo humano (dado a sus serios efectos adversos) y posee un límite mínimo de funcionamiento exigido para las diferentes técnicas empleadas en su detección de 0.3 μg/kg, mientras que el tianfenicol y el florfenicol son de uso permitido y poseen un límite máximo residual de 50 y 1000 μg/kg respectivamente. El florfenicol en los últimos años, ha sido uno de los antimicrobianos más utilizados en la industria del salmón, principalmente por su espectro de acción y eficacia.
Dada la similitud estructural de estos 3 fenicoles y la escasa información referente a la síntesis y contaminantes del principal agente utilizado en la industria del salmón, es posible que alguna traza de cloranfenicol y/o tianfenicol esté presente en productos farmacéuticos que contengan florfenicol como principio activo.
Este estudio consistió en determinar fenicoles a nivel de residuos en materias primas y productos farmacéuticos de florfenicol.
La cuantificación de florfenicol, cloranfenicol y tianfenicol se realizó por LC–MS/MS. Los espectros de primer y segundo orden y sus parámetros de fraccionamiento fueron desarrollados y optimizados como primera etapa. Posteriormente se desarrolló y optimizó un método cromatográfico para la cuantificación de estos 3 fenicoles en ausencia de matriz. Se incluyó ademas la obtención y optimización de espectros de primer y segundo orden y sus parámetros de fraccionamiento para florfenicol amina, con perspectiva a futuros estudios de determinación de fenicoles en tejidos de salmón.
Finalmente, se desarrolló, optimizó y validó la detección de florfenicol, tianfenicol y cloranfenicol en productos farmacéuticos de uso veterinario de florfenicol por el método propuesto. Los porcentajes de recuperación alcanzados por el método propuesto fueron de 100.4 ± 34% (expresado en concentraciones: 1.004 ± 0.3 ng/mL), demostrando una incertidumbre de 33.9%.
El método fue aplicado a muestras reales de productos farmacéuticos de uso veterinario de florfenicol, arrojando negativo a cloranfenicol en todos los casos, pero positivo a tianfenicol en concentraciones desde 0.419 hasta 0.475% para materias primas y entre 0.207 y 0.319% para productos terminados.
A la luz de los resultados obtenidos en este trabajo, resulta apremiante la implementación de controles exigentes para la detección de impurezas en medicamentos veterinarios debido al alto impacto, tanto a nivel de salud pública como a nivel económico, que se proyecta en las exportaciones de carnes de consumo humano<br>In response to the attack of the control`s need from certain opportunistic pathogens by giving a intensive farming system in the salmon Industry has provoked the use of antimicrobials from that part of the Industry. On this matter that took place in Chile, phenicols have been extensively used.
Through the extraction of Streptomyces venezuelae of chloramphenicol it came up the phenicols`s discovery which during the course of the years phenicols has been obtained synthetically. What this discovery did was taking within the study of derivatives such as thiamphenicol and florfenicol. According to the legislation in Chile and the European Union, chloramphenicol is exclusively forbidden in animals which can be eaten by people (due to its serious adverse effects) and it possess a minimum required performance limit for the different techniques applying in his detection of 0.3 μg/kg, while thiamphenicol and florfenicol are allowed because they have a maximum residual limit of 50 and 1000 μg/kg respectively. During the last years the florfenicol has been one of the most commonly antimicrobials used by the salmon Industry, mainly for his spectrum of action and effectiveness.
Giving the structural similarity of these 3 phenicols plus the lack of information concerning to the synthesis and contaminants from the main agent used in the salmon Industry. It is possible that some traces of chloramphenicol and/or thiamphenicol may be present in pharmaceutical products which contain florfenicol as the active ingredient.
The aim of this research was to determinate phenicols from the level residues in raw materials and pharmaceutical products which contain florfenicol. The quantification of florfenicol, chloramphenicol and thiamphenicol was performed by LC-MS/MS. The first step to develop the spectrum was to take them from the first and second order and fractionation parameters. Subsequently, it has developed and optimized a chromatographic method for the quantification of these 3 phenicols from the abbesses of matrix. It also was including the acquisition and optimization of spectra of first and second order and fractionation parameters for florfenicol amine, taking this into consideration for future phenicols studies for the determination in tissues of salmon.
Finally, it has develop, optimize and validate the detection of florfenicol, thiamphenicol and chloramphenicol in certain pharmaceutical products which are used in veterinary of florfenicol by the suggest method. The recovery percentage reach it by the propose method was 100.4 ± 34% or in terms of concentration and 1.004 ± 0.3 ng/mL, showing a 33.9% uncertainty.
The method was applied to pharmaceutical products from real samples of veterinary use of florfenicol, showing a negative chloramphenicol in all cases, but positive to thiamphenicol in concentrations from 0.419 to 0.475% for raw materials and between 0.207 and 0.319% for finished products.
In the light of the results obtained in this research, it is inevitable to implement a demanding control of the detection of impurities in veterinary drugs due to the high impact, both public health and economic level, which is projected in exportations of meat through the human consumption
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Pokrant, Huerta Ekaterina Valerievna. "Implementación y validación de metodologías analíticas por cromatografía líquida acoplada a espectometro de masas (LC MS/MS) para la detección de tetraciclinas en plumas y tejidos comestibles de pollos broiler." Tesis, Universidad de Chile, 2015. http://repositorio.uchile.cl/handle/2250/145973.
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Memoria para optar al Título Profesional de Médico Veterinario<br>Los antimicrobianos en animales productivos son la principal herramienta terapéutica para combatir enfermedades bacterianas, sin embargo su uso incorrecto puede derivar en la presencia de residuos en los productos y subproductos de origen animal. Cuando sobrepasan los Límites Máximos Residuales (LMR) son un riesgo para la salud de la población y una causa del aumento de la resistencia microbiana. Las plumas como subproducto son utilizadas en piensos y según estudios previos acumulan residuos antimicrobianos, de esta forma son una ruta de reingreso de residuos antimicrobianos a través de la cadena alimentaria. Para comparar concentraciones presentes de tetraciclinas en plumas con las de los tejidos, es imprescindible la validación de las metodologías analíticas implementadas para la detección de Tetraciclinas en estas matices por lo cual el objetivo del estudio fue validar metodologías analíticas mediante cromatografía liquida acoplado a detector de masas (LC-MS/MS) para detectar y cuantificar Oxitetraciclina, Clortetraciclina y sus metabolitos activos en plumas, músculo e hígado. Se utilizaron 20 pollos broiler criados con una dieta libre de antimicrobianos. El análisis fue mediante LC-MS/MS, utilizando columnas de extracción en fase sólida OASISTM HLB y sep-pak C18. Los resultados indican que las metodologías implementadas son válidas ya que cumplen con los criterios descritos por la FDA: VICH GL49 y la Directiva 2002/657/CE, siendo precisas, selectivas y lineales. Todas las curvas presentaron un coeficiente de determinación (R2) >0,95 y una recuperación para todos los analitos mayor a 90%. Mediante las metodologías validadas es posible detectar y cuantificar tetraciclinas, en las tres matrices con un límite de detección de 20 μg/kg-1<br>Antimicrobials in livestock are the main therapeutic tool for the combat of bacterial diseases, however the inadequate use may result in the presence of residues in animal edible and non-edible (byproducts) tissues. When exceeding Maximum Residue Limit (MRL) are a risk to the health of the population and a cause of increased antimicrobial resistance. Among the byproduct, feathers are used in feed and according to previous studies can accumulate antimicrobial residues, in this way is a route re-entry of antimicrobial residues via food chain. To compare concentrations of tetracycline present in feathers with tissue, it is essential to validate analytical methodologies implemented for the detection of tetracyclines in these matrices, so the aim of the study was to validate analytical methodologies by liquid chromatography coupled to mass spectrometry (LC-MS/MS) to detect and quantify Oxytetracycline, Chlortetracycline and it's metabolites in feathers, muscle and liver. 20 broiler chickens were used, raised with a diet free of antibiotics. The analysis was made by LC-MS / MS, using columns of solid phase extraction OASISTM HLB and sep-pak C18. The results indicate that the implemented methods are valid because they meet the criteria described by the FDA: VICH GL49 and Directive 2002/657 / EC, to be precise, selective and linear. All curves showed a coefficient of determination (R2)> 0.95 and a recovery for all analytes greater than 90%. By validated methods can detect and quantify Tetracyclines, in the three matrices with a detection limit of 20 mg / kg-1<br>Financiamiento: Proyecto Fondo de Investigación en Ciencias Veterinarias (FIV) 2013.
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Pokrant, Huerta Ekaterina Valerievna. "Evaluación de las concentraciones de florfenicol y su metabolito activo florfenicol amina en tejidos comestibles y plumas de pollo broiler mediante cromatografía líquida acoplada a espectrometría de masas (LC MS/MS)." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/144994.
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Tesis para optar al Grado de Magíster en Ciencias Animales y Veterinarias .<br>Los antibióticos son la principal herramienta terapéutica en el tratamiento de enfermedades de origen bacteriano en los sistemas de producción avícola. Sin embargo, si residuos de estos fármacos permanecen en productos destinados a consumo humano, por sobre los límites máximos residuales (LMR), se pueden producir diferentes efectos adversos sobre la población humana. En el caso de los subproductos como las plumas y a pesar de su uso para la alimentación de otras especies productivas, actualmente no existen estudios del comportamiento de varios antibióticos, como en el caso del florfenicol. De esta manera, en la presente tesis se evaluaron las concentraciones y depleción de florfenicol (FF) y su metabolito activo, florfenicol amina (FFA), en plumas y tejidos comestibles.
Para evaluar la depleción de FF y FFA, se utilizó un grupo de 80 pollos broiler criados bajo condiciones controladas, a los que se les administró un tratamiento con una formulación comercial de florfenicol al 10%, vía oral por cinco días. Dos metodologías analíticas por cromatografía líquida asociada a espectrometría de masas (LC-MS/MS), fueron implementadas y validadas, para asegurar que las concentraciones detectadas y cuantificadas de los analitos de interés fueran confiables y precisas. Las concentraciones detectadas a partir de las muestras experimentales fueron cuantificadas a través de la ecuación del análisis de regresión lineal de las curvas de calibración construidas en matriz fortificada con estándares certificados. En el estudio de depleción se estableció un tiempo de depleción de 99 días con un 95% para plumas, considerando el LD (20 μg kg-1) como punto de corte.<br>Antibiotics are the main therapeutic tool in the treatment of diseases of bacterial origin in poultry production systems. However, if residues of these drugs remain in products intended for human consumption, above the Residual Maximum Limits (MRLs), different adverse effects can occur on the human population. In the case of by-product as feathers and despite their use for feeding other productive species, there are currently no studies of the behavior of several antibiotics, like florfenicol. In this thesis work, concentrations and depletion of florfenicol (FF) and its active metabolite, florfenicol amine (FFA), in feathers and edible tissues were evaluated.
To evaluate FF and FFA depletion, a group of 80 broiler chickens raised under controlled conditions were used. They are treated with a commercial formulation of 10% florfenicol orally for five days. Two analytical methodologies by liquid chromatography associated to mass spectrometry (LC-MS / MS), were implemented and validated, to ensure that the detected and quantified concentrations of the analytes were reliable and accurate. The detected concentrations from experimental samples were quantified through the equation of the linear regression analysis of calibration curves constructed in matrix fortified with certified standards. In the depletion study established a 99-day depletion time with a 95% of confidence for feathers, considering LD (20 μg kg-1) as a cutoff point.<br>Financiamiento: Proyecto Fondecyt de Iniciación a la Investigación 11140530.
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Eisinger, Marc. "Index lexical du Codex de Florence." Paris 7, 1997. http://www.theses.fr/1997PA070009.
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Moraga, Garay Sergio Danilo. "Aplicación de espectroscopía de masas (Esi-Tof/MS) al estudio de polímeros inorgánicos de aluminio involucrados en la nucleación y crecimiento de nanopartículas ambientales de hidrobasaluminita." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/139465.
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Geólogo<br>La nanogeociencia así como la mineralogía ambiental son áreas de investigación que gracias a nuevos avances tecnológicos se están expandiendo rápidamente en múltiples direcciones enfocadas en la detección, caracterización y comprensión de fases no cristalinas, pobremente cristalinas y fases mixtas amorfo-cristalinas, así como también materiales nanométricos. En este contexto, los procesos no clásicos de nucleación y crecimiento cristalino presentes en soluciones acuosas representan un campo emergente que surge como alternativa al enfoque clásico con el cual ha sido abordado este tema (diferentes etapas de unión de monómeros básicos -átomos, iones o moléculas- entre sí). Estos procesos utilizan polímeros y nanopartículas más pequeñas como unidades básicas precursoras del crecimiento cristalino. La formación de nanopartículas de aluminio (comunes tanto en entornos naturales como procesos industriales), y más concretamente la precipitación de hidrobasaluminita (Al4SO4(OH)10 · 12-36H2O), puede ser considerada como el proxy perfecto para el estudio de estos procesos no clásicos.
Para caracterizar las especies poliméricas generadas durante la síntesis acuosa de nanopartículas de hidrobasaluminita la metodología utilizada en este trabajo es el análisis mediante ionización por electrospray acoplada a un espectrómetro de masas de tiempo de vuelo (ESI-TOF/MS). Esta técnica fue aplicada a cuatro soluciones de Al2(SO4)3 · 18H2O resultando en la identificación de 38 especies poliméricas catiónicas, ratificando la utilidad de esta técnica en el estudio de estos procesos no clásicos de cristalización permitiendo generar un primer volumen de datos para la elaboración de una base de datos con la masa y la fórmula de los polímeros de aluminio más comunes detectados en el sistema acuoso Al-S-O-H.
Los resultados mostraron una especiación variable, donde las especies reconocidas abarcan polímeros basados en Al, Al2, Al3, Al4, Al5, Al6 y algunos más complejos como Al11 o Al13. Dentro de los parámetros estudiados el efecto del pH fue el más notable de todos. Observándose una clara dependencia de este factor en la formación de complejos de mayor tamaño y carga. Por otra parte, la concentración de Al en la solución también mostró injerencia sobre la especiación de las muestras.
Finalmente, la metodología y resultados obtenidos, a pesar de las limitaciones asociadas, permiten acercarse a una caracterización más certera de los procesos que rigen la precipitación de hidrobasaluminita y la naturaleza de las especies que participan en éstos.
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Delgado, Latorre Cristopher Gustavo. "Identificación de compuestos cuticulares mediante GC-MS y su rol en colonias de Neotermes chilensis (Blattodea: Kalotermitidae)." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/148976.
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Título de Químico Ambiental.<br>En insectos eusociales, el reconocimiento y la comunicación entre compañeros de nido soportan la estructura social de la colonia. Estas conclusiones se basan más en estudios en himenópteros que en termitas (Blattodea). En las termitas se distinguen tres castas principales: reproductores primarios (reproducción); soldados (defensa); y obreras o pseudo-obreras (alimentación y cuidado de otras castas y jóvenes, mantenimiento y expansión del nido).
La comunicación entre compañeros de nido se produce generalmente por señales químicas. Dentro de estas son especialmente relevantes los compuestos cuticulares, particularmente los hidrocarburos. Estos recubren por completo la cutícula de los insectos y cumplen dos funciones: evitar la pérdida de agua y actuar como compuestos semioquímicos para el reconocimiento entre individuos. En este seminario, se estudió las diferencias cualitativas (escalamiento multidimensional) y cuantitativas (análisis de componentes principales- PCA) en los perfiles de hidrocarburos cuticulares entre castas y entre dos sitios de recolección, usando la termita endémica nidificadora de una pieza, Neotermes chilensis, a través de cromatografía de gases acoplada a espectrometría de masas, técnica que permite separar, identificar y cuantificar los componentes de una mezcla.
Se identificaron 27 hidrocarburos en la cutícula de N. chilensis, 19 metil-alcanos (70,4%), 7 n-alcanos (25,9%) y un n-alqueno (3,70%). Los análisis estadísticos mostraron diferencias significativas en la composición cualitativa y cuantitativa entre el sitio de recolección y entre las castas. Los principales resultados mostraron que pseudo-obreras y soldados eran distintos entre sí y de otras castas. Además se determinó los principales hidrocarburos responsables de las diferencias entre castas.
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En conclusión, en este seminario se demostró las diferencias cualitativas y cuantitativas complementarias de los perfiles de hidrocarburos cuticulares entre distintas castas y entre dos sitios de recolección diferentes de N. chilensis. Los resultados contribuyen con una interpretación química al fenómeno de reconocimiento intraespecífico en una termita nidificadora de una pieza.<br>In eusocial insects, recognition and communication between nestmates support the social structure of the colony. These conclusions are based mostly in studies concerning hymenopterans rather than termites (Blattodea). In termites, three main castes may be distinguished: primary reproductors (reproduction); soldiers (defense); and workers or pseudo-workers (feeding and taking care of young and of other castes, maintenance and expansion of the nest). During the swarming season, alates of both sex emerge from the parental colony, loose their wings, and eventually mate and found a new colony.
Communication among nestmates is usually based on chemical signals. Cuticular compounds, particularly hydrocarbons, have special relevance. They cover the cuticle of the insects and avoid water loss and function as semiochemicals for recognition among individuals. In this seminar, I studied qualitative (multidimensional scaling) and quantitative (principal component analysis- PCA) differences in cuticular hydrocarbon profiles between castes and between two collection sites, using the endemic one piece nesting termite, Neotermes chilensis; I used gas chromatography coupled to mass spectrometry, a technique, which allows the separation, identification and quantitation of the components of a mixture.
I identified 27 hydrocarbons in the cuticle of N. chilensis: 19 methyl-alkanes (70.4%), 7 n-alkanes (25.9%) and one n-alkene (3.70%). The statistical analyses showed significant differences in qualitative and quantitative compositions between collection site and between castes. The main results showed differences between pseudo-workers and soldiers, and also differences between them and the other castes.
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Furthermore, I determined the main hydrocarbons responsible for the differences between castes. In conclusion, in this seminary I demonstrated the complementary nature of qualitative and quantitative differences of the cuticular hydrocarbons profile between different castes and between two different collecting sites of N. chilensis. This result contributes with a chemical interpretation of the phenomenon of intraspecific recognition in a one-piece nesting termite.
Books on the topic "MS 2200"
1
Piccat, Marco. Lo spettacolo di Griselda: L'istoire de Griseldis, 1395 (BnF ms. fr. 2203). Società per gli studi storici, archeologicied artistici della Provincia di Cuneo, 2011.
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2
Robson, K. MS 220, papers of Eugene (John) Heimler (1922-90), 1939-93. University of Southampton, 1998.
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3
Tom, Badgett, ed. Official Sega Genesis and Game Gear strategies, 2ND Edition. Bantam Books, 1991.
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4
Sandler, Corey. Official Sega Genesis and Game Gear strategies, 3RD Edition. Bantam Books, 1992.
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Alley, Brian, Charles J. Brooks, and Patricia J. Barton. Designing MS-220. Pearson Education, Limited, 2002.
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Official Sega Genesis and Game Gear Strategies, '94 Edition. Random House, Electronic Publishing, 1993.
Find full textBook chapters on the topic "MS 2200"
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Nacharaju, Vijaya L., Yi-Chun Lee, Ghadir Salame, et al. "Determination of Urinary Cortisol Metabolites in Spot Urine of Patients with Uterine Cancer Utilizing Segmental GC/MS/MS." In CLINICAL/TRANSLATIONAL - Ovarian & Endometrial Cancer. The Endocrine Society, 2011. http://dx.doi.org/10.1210/endo-meetings.2011.part2.p31.p2-220.
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Lashmore-Davies, Adrian, and Mark Goldie. "To: Dr William Heberden. Battersea. 11 September 1751. [In another hand unidentified hand but signed by B.] Text: MS, BL Add. 32457, vol. 1, fol. 198." In The Unpublished Letters of Henry St John, First Viscount Bolingbroke. Routledge, 2020. http://dx.doi.org/10.4324/9781003074274-220.
Full textConference papers on the topic "MS 2200"
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Kuo, Chien-I., Heng-Tung Hsu, Chien-Ying Wu, et al. "A 40-nm-Gate InAs/In0.7Ga0.3As Composite-Channel HEMT with 2200 mS/mm and 500-GHz fT." In Related Materials (IPRM). IEEE, 2009. http://dx.doi.org/10.1109/iciprm.2009.5012458.
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Fonseca, Claudio Marcelo, Tuba Firincioglu, Gustavo Fernandez, and Alejandro Albertoni. "Reservoir Study of the Largest Oil Field in Argentina - A Two Reservoir 2200 Well Simulation Model." In SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, 2004. http://dx.doi.org/10.2118/90952-ms.
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Nwovu, Sampson Ojon, and O. M. O. Etebu. "Emissions Evaluation of Methanol-Gasoline Blend in Spark Ignition Engine." In SPE Nigeria Annual International Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/207184-ms.
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ABSTRACT This study experimentally evaluated exhaust emissions from methanol-gasoline blend (G95) and pure gasoline (G100) fuels using Spark Ignition (SI) engine. We produced methanol from Carbon (IV) Oxide (CO2) and water for transport and other applications. The methanol production involved simultaneous electrolysis of water within the anodic half-cell and catalytic reduction of CO2 within cathodic half-cell of an electrochemical set-up. We separated the produced methanol from its solution by fractional distillation. G95 was a mixture of 5 percent of methanol and 95 percent of gasoline. The experimental engine was naturally aspirated, single cylinder, 4-stroke with port-fueled injector. We operated the engine under constant load of 3000 kg with varying engine speeds of 2200, 2600, 3000, 3400, 3800, and 4200 rpm. The experimental test results showed that CO and uHC emissions by G95 are lower than that of G100 at all engine speeds. However, CO2 and lambda (λ) emissions by G95 are higher than that of G100 specifically at full load operations. The results found in this study highlight that application of methanol in transportation industry has high potential to lessen vehicle's emissions and improve atmospheric environment.
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Oazen, Eduardo Valente, Lionel Nelson Macauley, Otávio Borges Sertã, and Christopher Tsi Fen Siu. "Daisy Chain and Manifold-Based Subsea Architectures for Brazilian Pre-Salt." In Offshore Technology Conference. OTC, 2021. http://dx.doi.org/10.4043/31175-ms.
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Abstract Brazilian Pre-salts fields lie in approximately 2200 m w.d. in a challenging environment and are often characterized by highly corrosive produced fluids that pushed to the extreme the application of the most advanced material technology and engineering. Nevertheless, Lula, Sapinhoá, Mero and Búzios are definitively world-class prospects with production rates that may exceed 30.000 barrels per day per well. The development scheme of the Pre-salt fields followed the experience and the track record of the large number of deepwater fields that were previously developed in Brazil, in the post-salt regions, and is based on satellite wells tied to the floating production platform by means of dedicated production and service risers (i.e. each well has dedicated production and service lines). This satellite configuration offers the advantage to be simple, straightforward and resilient to field layout changes even during the project execution phase. However, the continuous pressure to which the Oil & Gas industry is exposed in order to increase profitability, reduce cost and, more recently, green house gas emission is encouraging Operators to evaluate different field architectures that are more traditionally implemented in other deepwater provinces outside Brazil and that the recent technology and construction asset developments made suitable also for a potential application in the Pre-salt fields. Moreover, those field architectures that are normally based on commingling of wells production are also prone to provide a faster production ramp-up and a reduced time to break even. This paper presents a description of possible Daisy Chain and Manifold-Based subsea architectures that are suitable to be applied to Brazilian pre-salt fields. The pros and cons of these alternative subsea layouts are explored. Additionally, cost and schedule analyses are presented to show the benefits of such architecture regarding CAPEX and ramp-up compared to satellite architecture, considering the "Brazilian pre-salt" scenario. Finally, a generic proposal for subsea architecture is presented for pre-salt developments jointly with practical solutions for typical operation demands related to flow assurance issues like, for instance, wax and hydrate management.
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Oke, S., M. Mphahlele, O. Ige, O. Falodun, B. Obadele, and P. Olubambi. "The Influence of Nano TiN Additions on Mechanical Properties and Fracture Behaviour of Spark Plasma Sintered SAF 2205." In MS&T17. MS&T17, 2017. http://dx.doi.org/10.7449/2017/mst_2017_1172_1174.
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Oke, S., M. Mphahlele, O. Ige, O. Falodun, B. Obadele, and P. Olubambi. "The Influence of Nano TiN Additions on Mechanical Properties and Fracture Behaviour of Spark Plasma Sintered SAF 2205." In MS&T17. MS&T17, 2017. http://dx.doi.org/10.7449/2017mst/2017/mst_2017_1172_1174.
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Gemse, F., S. Jahn, P. Schaaf, and S. Ulrich. "Influence of the Process Parameters on the Transformation Behaviour of 2205 Duplex Stainless Steel during Laser Beam Welding." In MS&T19. TMS, 2019. http://dx.doi.org/10.7449/2019mst/2019/mst_2019_1018_1026.
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Gemse, F., S. Jahn, P. Schaaf, and S. Ulrich. "Influence of the Process Parameters on the Transformation Behaviour of 2205 Duplex Stainless Steel during Laser Beam Welding." In MS&T19. TMS, 2019. http://dx.doi.org/10.7449/2019/mst_2019_1018_1026.
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Riebl, Sebastian, Marina Braun-Unkhoff, and Uwe Riedel. "A Study on the Emissions of Alternative Aviation Fuels." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-57361.
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Currently, the aviation sector is seeking for alternatives to kerosene from crude oil, as part of the efforts combating climate change by reducing greenhouse gas (GHG) emissions, in particular carbon dioxide (CO2), and ensuring security of supply at affordable prices. Several synthetic jet fuels have been developed including sustainable bio-kerosene, a low-carbon fuel. Over the last years, the technical feasibility as well as the compatibility of alternative jet fuels with today’s planes has been proven However, when burning a jet fuel, the exhaust gases are a mixture of many species, going beyond CO2 and water (H2O) emissions, with nitrogen oxides (NOx), carbon monoxide (CO), unburned hydrocarbons (UHC) including aromatic species and further precursors of particles and soot among them. These emissions have an impact on the local air quality as well as on the climate (particles, soot, contrails). Therefore, a detailed knowledge and understanding of the emission patterns when burning synthetic aviation fuels is inevitable. In the present paper, these issues are addressed by studying numerically the combustion of four synthetic jet fuels (Fischer-Tropsch fuels). For reference, two types of crude-oil based kerosenes (Jet A-1 and Jet A) are considered, too. Plug flow calculations were performed by using a detailed chemical-kinetic model validated previously. The composition of the multi-component jet fuels were imaged by using the surrogate approach. Calculations were done for relevant temperatures, pressures, residence times, and fuel equivalence ratios φ. Results are discussed for NOx, CO as well as benzene and acetylene as major soot precursors. According to the predictions, the NOx and CO emissions are within about ± 10% for all fuels considered, within the parameter range studied: T = 1800 K, T = 2200 K; 0.25 ≤ φ ≤ 1.8; p = 40 bar; t = 3 ms. The aromatics free GtL (Gas to Liquid) fuel displayed higher NOx values compared to Jet A-1/A. In addition, synthetic fuels show slightly lower (better) CO emission data than Jet A-1/A. The antagonist role of CO and NOx is apparent. Major differences were predicted for benzene emissions, depending strongly on the aromatics content in the specific fuel, with lower levels predicted for the synthetic aviation fuels. Acetylene levels show a similar, but less pronounced, effect.
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Duke, Lumi, Paul H. Kim, Julianne Cook Botelho, Regina G. Ziegler, and Hubert Vesper. "Abstract 2206: A new sensitive, accurate liquid chromatography-tandem mass spectrometry (LC-MS-MS) method to measure circulating estrogens, androgens, and progesterone in postmenopausal and premenopausal women." In Proceedings: AACR Annual Meeting 2018; April 14-18, 2018; Chicago, IL. American Association for Cancer Research, 2018. http://dx.doi.org/10.1158/1538-7445.am2018-2206.
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