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Effect of magnesium on the aluminothermic reduction rate of zinc oxide obtained from spent alkaline battery anodes for the preparation of Al–Zn–Mg alloys

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 458-465页

作者： Rocio Ochoa alfredo flores Jesus Torres Cinvestav-Saltillo

The aluminothermic reduction of zinc oxide（ZnO） from alkaline battery anodes using molten Al may be a good option for the elaboration of secondary 7000-series alloys. This process is affected by the initial content of Mg within molten Al, which decreases the surface tension of the molten metal and conversely increases the wettability of ZnO particles. The effect of initial Mg concentration on the aluminothermic reduction rate of ZnO was analyzed at the following values： 0.90wt%, 1.20wt%, 4.00t%, 4.25wt%, and 4.40wt%. The ZnO particles were incorporated by mechanical agitation using a graphite paddle inside a bath of molten Al maintained at a constant temperature of 1123 K and at a constant agitation speed of 250 r/min, the treatment time was 240 min and the ZnO particle size was 450？500 mesh. The results show an increase in Zn concentration in the prepared alloys up to 5.43wt% for the highest initial concentration of Mg. The reaction products obtained were characterized by scanning electron microscopy and X-ray diffraction, and the efficiency of the reaction was measured on the basis of the different concentrations of Mg studied.

关键词： aluminothermic reduction alkaline batteries zinc oxide waste utilization aluminum zinc magnesium alloys

Characterization by EBSD of Antimony-calcium Rich Phases Formed during Purification of Aluminum Scrap

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 647-649页

作者： MUIZ Rodrigo flores alfredo ORTIZ Juan RODRíGUEZ Nelly MARTíNEZ Fernando LUNA Jesús OROZCO Pilar Faculty of Engineering Autonomous University of Coahuila Camporedondo Unit CINVESTAV Saltillo Unit Department of Metal Mechanics Technological Institute of Saltillo Faculty of Engineering Autonomous University of Zacatecas

We studied the influence of antimony on the modification rate of the silicon eutectic with sodium and/or strontium for castiig of A1-Si alloys, and introduced controlled Ca and Sb to the system and studied the resulting compounds, which were determined to be CazSb and A1Sb. Scanning electron microscopy together with the complementary technique of electron backscatter diffraction （EBSD） were used to characterize the materials. The experimental results provided the basis for us to establish that antimony removal from AI occurs mainly through the reaction （Sb）A1 ＋ 2Ca = Ca^Sb ＋ A1.

关键词： aluminum alloys antimony contamination modification

Microstructural Feature of As-cast A-356 Alloy Modifiers with the Addition of SrO

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Journal of Wuhan University of Technology(Materials Science) 2014年第3期29卷 617-619页

作者： MU?IZ Rodrigo flores alfredo ORTIZ Juan RODRíGUEZ Nelly MARTíNEZ Fernando OROZCO Pilar LUNA Jesús Equihua Fabián García Adrián Faculty of Engineering Autonomous University of Coahuila Camporedondo UnitSaltillo Coahuila México CINVESTAV Saltillo Unit Department of Metal Mechanics Technological Institute of Saltillo Faculty of Engineering Autonomous University of Zacatecas FIME Autonomous University of Coahuila Unit

To explore the effect of strontium on the structure of as-cast A356 alloy, the strontium was incorporated to the alloy by metallothermic reduction of SrO where the mineral was added to the melt through the submerged powders injection technique. The evaluation of the modification of the eutectie silicon and the chemical analysis of samples were done using optical microscopy （OP） and inductively coupled plasma （ICP）, respectively, while microstructural analyses by scanning electron microscopy （SEM）, and the injection time was variable. Magnesium was added to the melt to increase the reactivity and reduce the surface tension of the molten aluminum. It was possible to increase the strontium content from 0 to 0.027% after 20 minutes treatment. This concentration was sufficient to bring about full modification structure of eutectic silicon of as cast alloy A 356 and the acceptable quality metallurgical of alloy.

关键词： modification microstmcture strontium eutectic silicon submerged powder injection

Pig Reproductive and Respiratory Syndrome Virus (PRRSV) Does Not Attach to Boar Sperm;It Affects Only the Velocity Pattern and the Mobility Pattern

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Journal of Biosciences and Medicines 2024年第4期12卷 216-228页

作者： Néstor Méndez Palacios Netzi Naidí Mendez Palacios Felicitas Vázquez flores José alfredo Galicia Domínguez Edgar Guadalupe Beltrán Rosas Maximino Méndez Mendoza Facultad de Medicina Veterinaria and Zootecnia-Benemé rita Universidad Aut&#243noma de Puebla Puebla Mexico Independent Advisor in the Porcine Area Puebla Mexico

The purpose of the study was to evaluate the sperm viability of semen infected with PRRSV viral particles, observing the effect of the Virus on the motility of boar sperm. The work was carried out at the FMVZ-BUAP Genetics and Reproduction Laboratory. 5 stallions were used. Each sample contained 1 × 106 sperm, the PRRS virus strain was ATCC-VR-2332 (0, 102, 104 and 106 copies of RNA/mL in triplicate), it was observed daily at the CASA;Hamilton Thorne®. Cells with MT (P 2 and 10X6 (P 2) 162.81 ± 10.65 and (106) 177.12 ± 5.77 vs 193.04 ± 4.62 of control. This indicates that altering these parameters would be related to fertility and the PRRS virus affects the LCV. Regarding the VSL, it was observed that the sperm infected with viruses 102, 104 and 106 of 48.00 ± 3.38, 49.88 ± 1.83 and 50.55 ± 2.24 Vs. 56.66 ± 1.68 of control respectively, the control would have greater possibilities of fertilizing the oocyte. In this study, it was found (P ≤ 0.01) in the VAP with 102 of 77.26 ± 5.16, 104 with 83.35 ± 2.41 and 106 with 81.29 ± 3.14 vs the control with 90.56 ± 2.07. Regarding the ALH there is (P 4 with 8.70 ± .26 and 106 with 9.64 ± 0.23 vs control 8.50 ± 0.27. The presence of different concentrations of PRRSV in boar semen induces changes in different types of sperm motility. Infection of ej

关键词： PRRSV Boar Sperms Velocity Pattern and Mobility Pattern

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生物柴油生产能使猪、鸡生产者从中受益

国外畜牧学（猪与禽） 2010年第3期30卷 40-41页

作者：张贤群 alfredo flores Ann Perry

生物燃料的开发不仅仅是一项寻找合适种类的生物质(如玉米粒、大豆油或其它原料)并将其转化成燃料的研究工作,科学家还必须从环境和经济方面为生物燃料副产品寻找最佳用途。

关键词：生物柴油生产者产能生物燃料猪鸡玉米粒生物质

Structural and Vibrational Study of PCBM

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Journal of Chemistry and Chemical Engineering 2011年第11期5卷 1034-1040页

作者： alfredo Tlahuice-flores Sergio Mejia-Rosales Instituto de Fisica Universidad Nacional Autonoma de Mexico Apartado Postal 20-364 01000 Mexico D. F. Mexico CICFIM-Facultad de Ciencias Fisico Matematicas Universidad Autonoma de Nuevo Leon San Nicolas de los Garza N. L. 66450 Mexico

The 1-(3-methoxycarbonyl) propyl-1-phenyl-(6,6)C61 (also called PCBM) is a C60 derivative widely used as an electron-acceptor in organic solar cells. To date, all the infrared spectra reported are experimental, mainly because of the calculations needed to study these structures are highly time-consuming. In this report we address for the first time the infrared spectrum calculation of PCBM with Cs symmetry by using the PW91/dnp level as implemented in the Dmol3 code. In this calculation we have found two intense peaks in the IR spectrum, that agree fairly with the 1187 and 1787 cm-1 measured experimentally.

关键词：结构有机太阳能电池振动 C60衍生物红外光谱谱计算甲氧羰基电子受体

Anthropometric Breast Measurements: Analysis of the Average Breast in the Mexican Female Population

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Journal of Biosciences and Medicines 2022年第3期10卷 124-135页

作者： David flores-Soto Jose C. Martinez-López Fernando Barbosa-Villarreal Fernando I. Recio-Espana Jaime A. García-Espinoza alfredo Chama-Naranjo Ana P. Campollo-Lopez D. Deluna-Gallardo Alejandro Costa-Dulche Cuahutemoc Márquez-Espriella Division of Plastic and Reconstructive Surgery Hospital Central Sur de Alta Especialidad de Petróleos Mexicanos Mexico City Mexico

Introduction: The elements and perception of beauty vary between populations around the world. To obtain better results, surgical techniques should be planned based on anthropometric characteristics of the race, location, and body mass index (BMI). Objectives: To determine which are the standard measurements and anatomical proportions of the breast in a healthy Mexican women population. Materials and Methods: Female Mexican volunteers between 20 and 60 years of age, without any history of breast illness or breast surgery were studied. Demographic information and standard breast anthropometric measurements were collected manually by one of the authors. For the statistical analysis a Student-T test was performed, and the Pearson correlation coefficient was obtained using the latest version of SPSS software. Results: 78 volunteers were included in the analysis. Mean height, weight and BMI were 1.6 m, 68.9 Kg, and 26.6 Kg/m2 respectively. The mean anthropometric values found were: Supra Sternal notch to nipple distance (SSN:N) 22 cm, Breast volume (BV) 372.6 cm3, Upper breast pole length (UBPL) 11 cm, Lower Breast Pole length (LBPL) 7.7 cm, Midline to Nipple distance (ML:N) 10.2 cm, Transverse diameter of the Nipple areola complex (NAC-T) 4.1 cm, Height of the Nipple Areola Complex (NAC-H) 4.1 cm, Base of the breast (BB) 13.4 cm, Upper Pole to Lower Pole Ratio (UPP:LPP) 58.9:41.1. A statistically significant difference between Right and left breast was not found. The UPP/ LPP ratio in our population is far different from what is considered internationally aesthetic (45:55). A positive correlation was found between weight/ BMI and SSN:N, BV, BB, ML:N and LBPL. Also between age and SSN:N, LBPL, BV and BB. Conclusion: This study sets the Anthropometric grounds in Mexican population for an objective individual patient analysis and comparison with the female population of this and other nations.

关键词： Average Breast Anthropometric Measurements Mexico Breast Anthropometric Measurements Mexico

Breast Reconstruction: Does It Worth to Start If the Patient Is Not Sure to Take All the Process Along?

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Journal of Biosciences and Medicines 2022年第8期10卷 201-209页

作者： Jesús Ricardo García-Corral José Martínez-Lopez Rodrigo Davila-Diaz Blanca Arambula-Sanchez Marco Cuervo-Vergara Fernando Barbosa-Villarreal Daniel De Luna Ana Priscila Campollo Lopez Fernando Isaac Recio Espana alfredo Chama Naranjo Jaime García Alejandro Costa David flores-Soto Selina Marioni-Manriquez Patricia Lopez-Medellin Erika Barlandas-Quintana Edgar Guillen-Martinez Steve Rodriguez-Alanis Cuahutemoc Marquez Departamento de Cirugía Plástica y Reconstructiva Hospital Central Sur de Alta Especialidad PEMEX Mexico City Mexico

Introduction: Breast cancer is the most common cancer in women worldwide, representing a major public health problem. There is still little information comparing the satisfaction of the patients who finished their process against the ones who start it but did not finish it. The aim of our retrospective study was to analyze the results in terms of satisfaction after one year of undergoing to complete breast reconstruction (CBR) vs incomplete breast reconstruction (IBR). Materials and Methods: Retrospective study of patients that underwent breast reconstruction (BR) surgery after mastectomy for breast cancer treatment. Performed at Hospital Central Sur de Alta Especialidad PEMEX in Mexico City, including patients from January 1, 2015 to January 01, 2020. Demographic baseline variables were included. BREAST-Q satisfaction questionnaires one year after the last reconstructive procedure were analyzed. Results: A total of 44 patients fulfilled the inclusion criteria. Of these 44 patients, 11 were included in the IBR group, and 33 patients in the CBR group. There were no statistically significant differences between the two groups in terms of age (IBR 56.09 vs CBR 53.06 years, p = 0.321);BMI (IBR 27.94 vs CBR 26.40, p = 0.253), time from mastectomy to first reconstructive procedure (IBR 22.8 vs CBR 31 months, p = 0.957), history of chemotherapy (IBR 27.3% vs CBR 33.3%, p = 0.709) and radiotherapy (IBR 54.5% vs CBR 42.4%, p = 0.484), additionally type of reconstruction, affected side or complication rate were not significantly different. Regarding postoperative satisfaction, only the second module of satisfaction with breasts displayed statistically significant differences, with a higher score in the CBR group (46.27 vs 52.27, p = 0.019). Other items explored didn’t show significant differences. Discussion: The data reported in this study suggest that regardless of whether the last stage of a BR is reached, the results in these settings can be very similar in terms of psych

关键词： BREAST-Q Breast Reconstruction Satisfaction Index Quality of Life Breast Cancer Patient’s Decision Making

Impact of liver enzymes on SARS-CoV-2 infection and the severity of clinical course of COVID-19

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Liver Research 2021年第1期5卷 21-27页

作者： Fátima Higuera-de la Tijera alfredo Servín-Caamaño Daniel Reyes-Herrera Argelia flores-López Enrique J.A.Robiou-Vivero Felipe Martínez-Rivera Victor Galindo-Hernández Oscar Chapa-Azuela Alfonso Chávez-Morales Victor H.Rosales-Salyano Multidisciplinary Team for the Attention and Care of Patients with COVID-19 Hospital General de México Dr.Eduardo LiceagaMexico CityMexico Gastroenterology and Hepatology Department Hospital General de México Dr.Eduardo LiceagaMexico CityMexico Internal Medicine Department Hospital General de México Dr.Eduardo LiceagaMexico CityMexico Hepatobiliary and Pancreatology Clinic Surgery DepartmentHospital General de México Dr.Eduardo LiceagaMexico CityMexico Intensive Care Unit Hospital General de México Dr.Eduardo LiceagaMexico CityMexico

Background and aim Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the virus responsible for the current pandemic,can have multi-organ *** studies show that liver injury could be a manifestation of the disease,and that liver disease could also be related to a worse *** aim was to compare the characteristics of patients with severe coronavirus disease 2019(COVID-19)due to SARS-CoV-2 who required intubation versus stable hospitalized patients to identify the early biochemical predictive factors of a severe course of COVID-19 and subsequent requirement for intubation,specifically in *** This was an observational case-control study nested in a cohort *** medical records of patients admitted for confirmed COVID-19 at a tertiary level center in Mexico City were *** and biochemical data were collected,and the characteristics of patients who required invasive mechanical ventilation(IMV)(cases)were compared with stable hospitalized patients without ventilation(controls).Results We evaluated 166 patients with COVID-19 due to SARS-CoV-2 infection;114(68.7%)were men,the mean age was 50.6±13.3 years,and 27(16.3%)required *** comparative analysis between cases and controls showed(respectively)significantly lower blood oxygen saturation(SpO_(2))(73.5±12.0%vs.83.0±6.8%,P<0.0001)and elevated alanine aminotransferase(ALT)(128(14–1123)IU/L vs.33(8–453)IU/L,P=0.003),aspartate aminotransferase(AST)(214(17–1247)vs.44(12–498)IU/L,P=0.001),lactic dehydrogenase(LDH)(764.6±401.9 IU/L vs.461.0±185.6 IU/L,P=0.001),and D-dimer(3463(524–34,227)ng/mL vs.829(152–41,923)ng/mL,P=0.003)*** in the cases group were older(58.6±12.7 years vs.49.1±12.8 years,P=0.001).Multivariate analysis showed that important factors at admission predicting the requirement for IMV during hospitalization for COVID-19 were AST≥250 IU/L(odds ratio(OR)=64.8,95%confidence interval(CI)7.5–560.3,P<0.0001)and D-dimer≥3500 ng/mL(OR=4.1,95

关键词： Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Coronavirus disease 2019(COVID-19) Liver enzymes D-dimer Disease severity Invasive mechanical ventilation(IMV) Multi-organ failure