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Possible Relevance of the Allende meteorite Conditions in Prebiotic Chemistry: An Insight into the Chondrules and Organic Compounds

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Advances in Biological Chemistry 2023年第3期13卷 82-99页

作者： Alejandro Heredia Barbero Héctor G. vázquez López Adriana L. meléndez López Jorge A. Cruz Castañeda Daniel Luna Laviada Karina E. Cervantes de la Cruz victor m.za Laguna vladimir A. Basiuk Ivonne Rosales Chávez Alicia Negrón mendoza Sergio Ramos Bernal Laboratorio de Evolución Química Departamento de Química de Radiaciones y Radioquímica Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Programa de Posgrado en Ciencias Químicas Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Departamento de Física Facultad de Ciencias Carrera de Ciencias de la Tierra Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Departamento de Física de Plasmas e Interacción de Radiación con materia Instituto de Ciencias Nucleares Ciudad Universitaria Ciudad de México México Departamento de Física y Química Teórica Facultad de Química Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México

The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the magnetic minerals present in ordinary and carbonaceous chondrites, providing information on the evolution of magnetic fields. The interaction of organic compounds with magnetic minerals is a possible source of chemical diversity, which is crucial for molecular evolution. Carbon compounds in meteorites are of great scientific interest for a variety of reasons, such as their relevance to the origins of chirality in living organisms. This study presents the characterization of organic and mineral compounds in the Allende meteorite. The structural and physicochemical characterization of the Allende meteorite was accomplished through light microscopy, powder X-ray diffraction with complementary Rietveld refinement, Raman and infrared spectroscopy, mass spectrometry, scanning electron microscopy, and atomic force microscopy using magnetic signal methods to determine the complex structure and the interaction of organic compounds with magnetic Ni-Fe minerals. The presence of Liesegang-like patterns of chondrules in fragments of the Allende structure may also be relevant to understanding how the meteorite was formed. Other observations include the presence of magnetic materials and nanorod-like solids with relatively similar sizes as well as the heterogeneous distribution of carbon in chondrules. Signals observed in the Raman and infrared spectra resemble organic compounds such as carbon nanotubes and peptide-like molecules that have been previously reported in other meteorites, making the mexican Allende meteorite a feasible sample for the study of the early Earth and exoplanetary bodies.

关键词： Allende meteorite Carbonaceous Chondrite Light microscopy X-Ray Diffraction with the Rietveld method Raman Spectroscopy Attenuated Total Reflectance Infrared Spectroscopy mass Spectrometry Scanning Electron mi-croscopy Energy Dispersive X-Ray Spectroscopy magnetic Force microscopy

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Corrosion Behavior of API 5L X52 Steel under High Concentrations of H₂S/CO₂ Gases

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materials Sciences and Applications 2016年第10期7卷 623-643页

作者： mónica Jazmín Hernández Gayosso Gerardo zavala Olivares Saúl Bautista Fragoso Gabriel Ernesto Blanco del valle Daniel mauricio Godínez Oidor víctor Ángel Rodríguez Góm.z Instituto mexicano del Petróleo Eje Central Lázaro Cárdenas Norte 152 San Bartolo Atepehuacan Gustavo A. Madero Ciudad de México México Pemex Exploración Producción Carretera Carmen-Puerto Real Km 4.5 Colonia Renovación Edificio Kaxan Campeche México

In the present work, the susceptibility of API 5L X52 steel to corrosion processes was evaluated in the presence of high contents of hydrogen sulfide and carbon dioxide. Gravimetric tests and surface analyses were carried out to establish both the corrosion rate and damage type exhibited by the metal. The obtained results indicate that the hydrogen sulfide is the most active gas in the corrosion processes that took place, quite above carbon dioxide. The main observed corrosion products were iron sulfides and the typical damage associated with hydrogen sulfide presence was Sulfide Stress Cracking (SSC). The surface damage evidences the presence of cracks with considerable magnitude and metal loss as consequences of the corrosion processes. Likewise, the presence of oxygen in the system modifies the displayed corrosion type, where corrosion products such as iron oxides and reduction in the number and extent of cracks are observed. On the other hand, the addition of a film-forming corrosion inhibitor based on modified imidazolines eliminates completely the development of cracks, although under certain test conditions, it can favor localized pitting corrosion.

关键词： H2S Corrosion Cracking Corrosion Inhibition

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Comparing the biogeochemical functioning of two arid subtropical coastal lagoons:the effect of wastewater discharges

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Ecosystem Health and Sustainability 2021年第1期7卷 49-60页

作者： Julio medina-Galván Carmen Cristina Osuna-martínez Gustavo Padilla-Arredondo martín Gabriel Frías-Espericueta Ramón Héctor Barraza-Guardado JoséAlfredo Arreola-Lizárraga Facultad de Ciencias del mar Universidad Autónoma de SinaloaMazatlánMéxico Programa de Planeación Ambiental y Conservación Centro de Investigaciones Biológicas del NoroesteS.C.GuaymasMéxico Departamento de Investigaciones Científicas y Tecnológicas de la Universidad de Sonora HermosilloMéxico

Nutrient flux,net metabolism,and N2 fixation and denitrification processes were estimated and compared in two semi-arid subtropical coastal lagoons in the Gulf of California:El Soldado(ES),where no wastewater is discharged,and El Rancho(ER),where shrimp farm effluents are regularly discharged.Biogeochemical processes were evaluated with the LOICz model.Flushing time wasms.Nutrient fluxes were higher in ER than in ES and both systems acted as nutrient sinks for most of the year.ER showed a larger nutrient flow rate in the summer and autumn due to the input of shrimp-farm effluents.Nitrogen fluxes increased in both ER and ES in the winter in response to the increased nutrient supply from coastal upwellings.ER and ES both showed autotrophic metabolism and N2 fixation in the spring,autumn,and winter,but heterotrophic metabolism and denitrification in the summer.Denitrification dominated in ER(−2.21 mmol m^(2)day^(−1))and values were higher than those estimated in ES(−0.45 mmol m^(2)day^(−1)).The comparative analysis between ES and ER evidenced the significant changes in its biogeochemical performance caused by the input of anthropogenic nutrients,and can orient the environmental management of coastal lagoons.

关键词： Coastal lagoons nutrient budgets net ecosystem metabolism Gulf of California

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Hydatidosis and the duodenum: A systematic review of the literature

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World Journal of meta-Analysis 2020年第3期8卷 265-274页

作者： víctor de la Fuente-Aguilar Patricia Beneitez-mascaraque Sergio Bergua-Arroyo maría Fernández-Riesgo Irene Camón-García Iris Cruza-Aguilera Kennia Ugarte-Yáñez Josém Ramia Faculty of medicine Universidad of AlcaláAlcaláde Henares 28801Spain Servicio de Cirugía General y del Aparato Digestivo Hospital General Universitario de Alicante and Institute for Health and Biomedical Research(ISABIAL)Alicante 03010Spain

BACKGROUND Injury to the duodenum(fistula formation,compression,or other complications)by a hydatid cyst(HC)is an exceptional complication.AIm To perform a systematic review of the literature on the fistulization of HC in the duodenum.mETHODS Following PRISmA guidelines,a search for HC with duodenal involvement was carried out in the databases of Pubmed,SCielo and EmBASE without time limits.RESULTS Fourteen patients were identified,seven men and seven women,with a mean age of 53.14 years(SD=17.65,range:28-78).Three out of the 14(21%)had HC relapse.The most frequent clinical manifestations were abdominal pain and nausea and/or vomiting.various imaging studies were performed in almost all cases,the most commonly used being abdominal computed tomography(10/14,71%).A range of surgical techniques were reported,most frequently HC drainage(41%)and enucleations(16%).Ten of the 14 patients had no complications and one patient died.The follow-up period and recurrences could not be determined.CONCLUSION The most frequent symptoms were abdominal pain,nausea and vomiting.Computed tomography was the most used diagnostic imaging technique,and HC drainage and fistula closure via laparotomy was the most frequent treatment.However,all diagnostic and therapeutic options for HC fistulizing the duodenum had a low level of evidence.

关键词： Echinococcosis Hydatidosis Duodenum Surgery Review

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metabolic syndrome as a risk factor for gallstone disease

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World Journal of Gastroenterology 2005年第11期11卷 1653-1657页

作者： Nahum méndez-Sánchez Norberto C. Chavez-Tapia Daniel motola-Kuba Karla Sanchez-Lara Guadalupe Ponciano-Rodríguez Héctor Baptista martha H. Ramos misael Uribe Departments of Biomedical Research and Gastroenterology and Liver Unit

AIm: To establish an association between the presence of metabolic syndrome and the development of gallstone disease.mETHOIDS: We carried out a cross-sectional study in a check-up unit in a university hospital in mexico City. We enrolled 245 subjects, comprising 65 subjects with gallstones (36 women, 29 men) and 180 controls (79women and 101 men without gallstones). Body mass index, waist circumference, blood pressure, plasma insulin, and serum lipids and lipoproteins levels were measured. Insulin resistance was calculated by homeostasis model assessment. Unconditional logistic regressionanalysis (univariate and multivariate) was used to calculate the risk of gallstone disease associated with the presence of at least three of the criteria (Adult Treatment Panel Ⅲ). Analyses were adjusted for age and sex.RESULTS: Among 245 subjects, metabolic syndrome was present in 40% of gallstone disease subjects, compared with 17.2% of the controls, adjusted by age and gender (odds ratio (OR) = 2.79; 95%CI, 1.46-5.33; P = 0.002),a dose-dependent effect was observed with each component of metabolic syndrome (OR = 2.36, 95%CI, 0.72-7.71;P = 0.16 with one component and OR = 5.54, 95%CI,1.35-22.74; P = 0.02 with four components of metabolic syndrome). Homeostasis model assessment was significantly associated with gallstone disease (adjusted OR = 2.25;95%CI, 1.08-4.69; P = 0.03).CONCLUSION: We conclude that as for cardiovascular disease and diabetes mellitus, gallstone disease appears to be strongly associated with metabolic syndrome.

关键词：代谢综合症胆结石心血管疾病糖尿病

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Reservoir Processes Related to Exploitation in Los Azufres (méxico) Geothermal Field Indicated by Geochemical and Production monitoring Data

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International Journal of Geosciences 2015年第9期6卷 1048-1059页

作者： víctor manuel Arellano Rosa maría Barragán miguel Ramírez Siomara López Alfonso Aragón Adriana Paredes Emigdio Casimiro Lisette Reyes Instituto de Investigaciones Eléctricas Gerencia de Geotermia Cuernavaca México Comisión Federal de Electricidad Gerencia de Proyectos Geotermoeléctricos Morelia México Comisión Federal de Electricidad Residencia Los Azufres Campamento Agua Fría México

A combined analysis of geochemical and production data of 39 wells of the Los Azufres (mexico) geothermal field (227.4 mWe) over time was developed to investigate the exploitation-related processes for 2003-2011. In the south zone, important effects of reinjection were observed through Cl increases in some wells (up to 8000 mg/kg) while in wells with significant boiling, Cl has decreased. In most of the north zone wells, the variations in gas data indicated boiling and condensation of a highly gas-depleted brine, which seems to consist of reinjection fluids. It is suggested that this process maintains the production in the zone relatively stable. The main reservoir exploitation-related processes found were: 1) production of reinjection returns;for this, it was possible to distinguish a) wells that produce liquid and steam from injection, and b) wells that produce steam from injection and sometimes condensed steam from injection;2) boiling: two types of boiling were identified: a) boiling with steam gain, and b) boiling with steam loss. The results indicated that an effective reservoir recharge occurs since very moderate production declining rates were found.

关键词： Los Azufres Geothermal Field Well Simulation Fluid Geochemistry Well Bottom Conditions Production Wells

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Spectral Comparison of Real Spectra with Site Effects Included vs mOC-2008 Teorical Spectra for Guadalajara City, mexico

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Open Journal of Civil Engineering 2013年第3期3卷 194-201页

作者： Héctor E. Rodríguez Lozoya Tonatiuh Domínguez Reyes Alfredo Reyes Salazar Edén Bojórquez mora Héctor E. Rodríguez Leyva Facultad de Ingeniería Universidad Autónoma de Sinaloa México D.F. México Observatorio vulcanológico Universidad de Colima México D.F. México

Guadalajara city is the capital of the mexican federal state of Jalisco. It is located close to the Pacific coast and is subjected to a large seismic risk. We present a seismic response study for some sites along the city. We calculated response spectra of shear-waves by using seismic records of actual earthquakes registered on rock and near the source as Green functions and propagated them trough a flat and horizontal layered media using a linear equivalent method to compare them with the response spectra calculated according to the Federal Commission of Electricity (CFE) seismic design buildings manual (mOC-2008, 2008) which is widely used as reference on construction projects in mexico. Our results show that mOC-2008 manual underestimates the spectral amplitudes and frequency band for the response spectra.

关键词： Response Spectra Guadalajara Seismic Records Green Function

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Hexavalent Chromium Removal by Citrus limonium Shell

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Open Journal of Inorganic Non 2012年第3期2卷 19-24页

作者： Juan manuel vargas-morales Diana Bautista-mata Juan F. Cárdenas-González víctor manuel martínez-Juárez Ismael Acosta-Rodríguez área Académica de medicina veterinaria y zootecnia Instituto de Ciencias AgropecuariasUniversidad Autónoma del Estado de Hidalgo Tulancingo de Bravo México Laboratorio de micología Experimental Centro de Investigación y de Estudios de Posgrado Facultad de Ciencias Químicas Universidad Autónoma de San Luis Potosí San Luis Potosí México

We studied the Chromium(vI) removal capacity in aqueous solution by the lemon shell, using the diphenylcarbazide method to evaluate the metal concentration. So, the highest biosorption of the metal (50 mg/L) occurs within 100 minutes, at pH of 1.0, and 28°C. According to temperature, the highest removal was observed at 60°C, in 11 minutes, when the metal (1 g/L) is completely adsorbed. At the analyzed concentrations of Cr(vI), lemon shell, showed excellent removal capacity, besides it removes efficiently the metal in situ (97.2% removal, 7 days of incubation, 5 g of biomass). After 1 hour of incubation the studied biomass reduces 1.0 g of Cr(vI) with the simultaneous production of Cr(III);so it can be used to eliminate it from industrial wastewater.

关键词： Chromium(vI) Biosorption Remotion Biomass Chromium(III)

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A Review of Geothermal Type-Curves with Damage Effect: A Case of Practical Apply to a mexican Geothermal Field

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International Journal of Geosciences 2012年第3期3卷 591-600页

作者： Siomara López-Blanco Alfonso Aragón-Aguilar víctor Arellano-Góm.z Georgina Izquierdo-montalvo Sócrates Santoyo-Gutiérrez Abel Hernández-Ochoa Instituto de Investigaciones Eléctricas Reforma 113 Col. Palmira Cuernavaca Morelos México Universidad Popular de la Chontalpa Carr. Cárdenas-Huimanguillo km. 2.0 Cárdenas Tabasco México

A review of the art state was developed about the inflow relationships and their application for reservoir characterization. The theoretical development of the methodology for determining the damage effect using type-curves of the inflow relationships was shown. We show the process followed for achieve the geothermal type-curve affected with damage for reservoirs with mean salinities of 30000 ppm and temperatures up to 350℃. This type-curve was applied using measurement production data in a mexican geothermal field. According with the obtained results is shown that the methodology for determining the damage effect using production measurements is a sure alternative for the damage effect calculation. It was used an alternative methodology in order to validate the damage presence and the obtained results were consistent. Last thing shows that both methodologies can be combined as a confident manner.

关键词： Geothermal Reservoir Inflow Performance Relationships Type-Curves Damage Effect Well Production mass Flow Rate Output Curves

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An Application of Bessel Functions： Study of Transient Flow in a Cylindrical Pipe

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Journal of mathematics and System Science 2016年第2期6卷 72-79页

作者： A. E. García Luz maría García Cruz Héctor Luna-García Area de Fisica Atómica molecular Aplicada CBL UAM-A Avenida San Pablo 180 Colonia Reynosa Azcapotzalco México D.F. 02200 México

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