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Characteristics of SnO_(2):F Thin Films Deposited by Ultrasonic Spray Pyrolysis:Effect of Water Content in Solution and Substrate Temperature

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Materials Sciences and Applications 2012年第10期3卷 690-696页

作者： Mario Alberto Sánchez-García arturo maldonado Luis Castañeda Rutilo Silva-González María de la Luz Olvera Institute of Physics National Autonomous University of Mexico(UNAM)Apartado Postal 20-364México D.F.04510Mexico Electrical Engineering Department Solid State Electronics SectionApartado 14740México D.F.07360Mexico Institute of Physics Autonomous Meritorious University of PueblaApartado Postal J-48Puebla 72570Mexico

Fluorine doped tin oxide, SnO2:F, thin films were deposited by ultrasonic chemical spray starting from tin chloride and hydrofluoric acid. The physical characteristics of the films as a function of both water content in the starting solution and substrate temperature were studied. The film structure was polycrystalline in all cases, showing that the intensity of (200) peak increased with the water content in the starting solution. The electrical resistivity decreased with the water content, reaching a minimum value, in the order of 8 × 10-4 Ωcm, for films deposited at 450℃ from a starting solution with a water content of 10 ml per 100 ml of solution;further increase in water content increased the corresponding resistivity. Optical transmittances of SnO2:F films were high, in the order of 75%, and the band gap values oscillated around 3.9 eV. SEM analysis showed uniform surface morphologies with different geometries depending on the deposition conditions. Composition analysis showed a stoichiometric compound with a [Sn/O] ratio around 1:2 in all samples. The presence of F into the SnO2 lattice was detected, within 2 at % respect to Sn.

关键词： Tin Oxide Ultrasonic Spray Pyrolysis Transparent Conducting Oxides TCO

Guidelines for rational design of high-performance absorbents:A case study of zeolite adsorbents for emerging pollutants in water

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Green Energy & Environment 2017年第4期2卷 363-369页

作者： Xiaoxuan Wei Ya Wang arturo J.Hernndez-maldonado Zhongfang Chen Department of Chemistry Institute for Functional Nanomaterials University of Puerto Rico Rio Piedras Campus Department of Chemical Engineering Institute for Functional Nanomaterials University of Puerto Rico Mayagüez Campus

Rational design is important to achieve high-performance sorbents used to remove the contaminants of emerging concern(CECs) from ***, it is hard to propose effective design guidelines due to the lack of a clear understanding of the interaction mechanisms. By means of systematic quantum chemical computations, as a case study, we investigated the interactions between zeolite X/M^(n+)-zeolite X(Si/Al=1,M^(n+)=Cu^(2+) and Ni^(2+)) and three commonly used CECs(namely salicylic acid, carbamazepine and ciprofloxacin) in water to clarify the adsorption mechanisms. Our computations found that anionic salicylic acid cannot be adsorbed by neither zeolite X nor M^(n+)-zeolite X in neutral water due to the high electrostatic repulsion. In comparison, carbamazepine and ciprofloxacin have favorable binding energies with both zeolite X and M^(n+)-zeolite X, and their interactions with M^(n+)-zeolite X are stronger due to the joint effects of H-bond, metal complexation and electrostatic interaction. The adsorption loading of ciprofloxacin, which has a large molecular size, on M^(n+)-zeolite X is limited due to the steric hindrance. In general, steric hindrance, electrostatic interaction, H-bond and metal complexation are dominant factors for the examined systems in this study. Thus, for the design of high-performance absorbing materials, we should fully consider the molecular properties of pollutants(molecular size, surface electrostatic potential and atomic type, etc.), and properly enhance the favorable effects and avoid the unfavorable factors as much as possible under the guidance of the interaction mechanisms.

关键词： Adsorption mechanism Adsorbent design guidelines Quantum chemical computations Contaminants of emerging concern Zeolite X

Zeolite-templated carbons as effective sorbents to remove methylsiloxanes and derivatives:A computational screening

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Green Energy & Environment 2021年第6期6卷 884-892页

作者： Shiru Lin Kaitlyn A.Jacoby Jinxing Gu Dariana R.Vega-Santander arturo J.Hernaandez-maldonado Zhongfang Chen Department of Chemistry University of Puerto RicoRío PiedrasSan JuanPR 00931USA Department of Chemistry&Biochemistry Elizabethtown CollegeElizabethtownPA 17022USA Department of Chemical Engineering University of Puerto RicoMayaguez CampusMayaguezPR 00681USA

Though widely used in our daily lives,volatile methylsiloxanes and derivatives are emerging contaminants and becoming a high-priority environment and public health *** effective sorbent materials can remove siloxanes in a cost-effective ***,by means of Grand Canonical Monte Carlo(GCMC)simulations,we evaluated the potentials of the recently proposed 68 stable zeolite-templated carbons(ZTCs)(PNAS 2018,115,E8116-E8124)for the removal of four linear methylsiloxanes and derivatives as well as two cyclic methylsiloxanes by the calculated average loading and average adsorption energy *** ZTCs,namely ISV,FAU1,FAU3,and H8326836,were identified with the top 50%adsorption performance toward all the six targeted contaminants,which outperform activated *** first principles computations revealed that steric hindrance,electrostatic interactions(further enhanced by charge transfer),and CH-p interactions account for the outstanding adsorption performance of these *** work provides a quick procedure to computationally screen promising ZTCs for siloxane removal,and help guide future experimental and theoretical investigations.

关键词： Zeolite-templated carbons Contaminants of emerging concern Methylsiloxanes GCMC simulations Density functional theory calculations

Evaluation of Multiple-Use Cover Crops under Rainfed during Two Seasons in Yucatan, Mexico

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American Journal of Plant Sciences 2014年第8期5卷 1069-1080页

作者： Castillo-Caamal José Bernardino Caamal-maldonado Jesús arturo Belmar-Casso Roberto Trejo Lizama Wilberth Campus de Ciencias Biológicas y Agropecuarias―Universidad Autónoma de Yucatán Mérida México

The aim of the study was assessing seven legumes as cover crops during cropping seasons of the years 2000 and 2001 in the central region of the Yucatan. An experimental design of randomized blocks with arrangement of split plots was used;where treatment was the legume, and sub-treatment, was the management of defoliation, 90 days after sowing (DAS) or after harvesting the grain (AHG). Treatments were: short-cycle seed white lima bean (Phaseolus lunatus), long-cycle seed white lima bean (Phaseolus lunatus), cowpea (Vigna unguiculata), dwarf velvet bean (Mucuna pruriens var. utilis), ash velvet bean (Mucuna pruriens var. utilis), sword bean (Canavalia ensiformis) and red rice bean (Vigna umbellata). It was collected data on coverage and biomass production, grain, leaf litter and stubble yields, biomass and relative frequency of weeds, pH, total nitrogen, organic matter (OM), potential anaerobic mineralization of nitrogen (MPAN) and soil CO2 evolution. Coverage varied from 70% to 90%;and biomass from 1900 to 2500 kg·DM·ha-1 at 90 DAS in ash velvet bean (AVB) and sword bean (SB). Stubble yielded from 800 to 2200 kg·DM·ha-1. The SB reached ~3200 kg·DM·ha-1 of grain yield in the first cropping season and it was reduced in the second cropping season. AVB and SB reduced the biomass of weeds from 890 to 780 kg·DM·ha-1. The OM of soil reached 14.9% in AVB. NH4, pH, and soil CO2 evolution remained without significant changes by effect of legumes.

关键词： Legumes Biomass Weeds Soil Properties

Submegahertz spectral width photon pair source based on fused silica microspheres

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Photonics Research 2021年第11期9卷 2237-2252页

作者： ERASTO ORTIZ-RICARDO CESAR BERTONI-OCAMPO MONICA maldonado-TERRON arturo GARCIA ZURITA ROBERTO RAMIREZ-ALARCON HECTOR CRUZ RAMIREZ R.CASTRO-BELTRAN ALFRED B.U’REN Instituto de Ciencias Nucleares Universidad Nacional Autonoma de MexicoApartado Postal 70-54304510 MexicoD.F.Mexico Centro de Investigaciones en Optica A.C. Loma del Bosque 115Colonia Lomas del Campestre37150 LeonGuanajuatoMexico Departamento de Ingenieria Fisica Cuerpo Academico de Mecanica EstadisticaDivison de Ciencias e IngenieriasUniversidad de Guanajuato37150 LeonGuanajuatoMexico

High-efficiency submegahertz bandwidth photon pair generators will enable the field of quantum technology to transition from laboratory demonstrations to transformational applications involving information transfer from photons to *** spontaneous parametric processes are able to achieve high-efficiency photon pair generation,the spectral bandwidth tends to be relatively large,as defined by phase-matching *** solve this fundamental limitation,we use an ultrahigh quality factor(Q)fused silica microsphere resonant cavity to form a photon pair *** present the full theory for the spontaneous four-wave mixing(SFWM)process in these devices,fully taking into account all relevant source characteristics in our *** exceptionally narrow(down to kilohertz-scale)linewidths of these devices result in a reduction in the bandwidth of the photon pair generation,allowing submegahertz spectral bandwidth to be ***,using a pump source centered around 1550 nm,photon pairs with the signal and idler modes at wavelengths close to 1540 and 1560 nm,respectively,are *** herald a single idler-mode photon by detecting the corresponding signal photon,filtered via transmission through a wavelength division multiplexing channel of *** demonstrate the extraction of the spectral profile of a single peak in the single-photon frequency comb from a measurement of the signal–idler time of emission *** improvements in device design and experimental methods enabled the narrowest spectral width(Δν=366 k Hz)to date in a heralded single-photon source based on SFWM.

关键词： fused silica spectral

Effect of Water Regimes on Dietary Fiber, Polyphenols and Antioxidant Capacity of Black and Pinto Beans

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Agricultural Sciences 2014年第4期5卷 342-352页

作者： Maribel Ovando-Martínez Salvador Horacio Guzmán-maldonado Senay Simsek Luis arturo Bello-Pérez Perla Osorio-Díaz CEPROBI Instituto Politécnico Nacional Yautepec México CEPROBI Instituto Politécnico Nacional Yautepec México Department of Plant Sciences North Dakota State University Fargo USA Department of Plant Sciences North Dakota State University Fargo USA Unidad de Biotecnología del Campo Experimental Bajío INIFAP Celaya México

Beans are rich in dietary fiber and polyphenols;however, growing conditions may affect the occurrence of these components. The effect of irrigation and rain fed conditions on dietary fiber, indigestible fraction, polyphenols and antioxidant capacity of Black 8025 and Pinto Durango bean cultivars grown in Mexico have been determined. Total dietary fiber decreased in beans grown under rain fed conditions compared to those grown under irrigation. The water regimes had an effect on the total indigestible fraction for Black 8025 bean. The extractable polyphenols were affected by the water regimes, while the antioxidant capacity of extractable and non-extractable polyphenols was dependent on the bean variety. Cooking the beans altered the extractable and non-extractable polyphenols and the antioxidant capacity. Also, the antioxidant properties and some extend, the digestibility of non-digestible carbohydrates of beans were affected by water regimes. This information could be taken into account for dry bean breeding programs to improve the nutritional quality of beans.

关键词： Water Regimes Dietary Fiber Indigestible Fraction Polyphenols Antioxidant Capacity Cooking

Adaptation of international coronavirus disease 2019 and breast cancer guidelines to local context

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World Journal of Clinical Oncology 2021年第1期12卷 31-42页

作者： Guillermo arturo Valencia Silvia Neciosup Henry L Gómez Maria Del Pilar Benites Silvia Falcón David Moron Karin Veliz Mike maldonado Rodrigo Auqui Department of Medical Oncology Instituto Nacional de Enfermedades Neoplásicas(INEN)Surquillo 15000LimaPeru Clínica Oncosalud–AUNA Surquillo 15000LimaPeru Breast Cancer Unit Hospital Nacional Edgardo Rebagliati MartinsLima 15000Peru Department of Medical Oncology Centro Oncológico AliadaLima 15000Peru Department of Medical Oncology Hospital Nacional Carlos Alberto Seguín EscobedoArequipa 04001Peru Department of Medical Oncology Hospital Nacional Ramiro PrialéPrialéHuancayo 12000Peru Department of Medical Oncology Instituto Regional de Enfermedades Neoplásicas(IREN)Trujillo 13001Peru Department of Medical Oncology Hospital Nacional Almanzor Aguinaga AsenjoChiclayo 14001Peru

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(a novel coronavirus),which was first identified amid an outbreak of respiratory illness cases in Wuhan,China and declared a global health emergency,is currently considered an additional challenge in the management of patients with breast cancer(BC).Cancer patients are more vulnerable to becoming infected with severe acute respiratory syndrome coronavirus 2 and are more likely to suffer additional complications that can increase *** those BC patients who require more urgent therapy than others in the current situation is *** recommendations are based on and have been adapted from those similarly published by international scientific societies for BC *** are divided mainly by clinical stage(early,advanced),subtype[luminal,human epidermal growth factor receptor 2(HER2),triple-negative],or type of medical treatment and setting(neoadjuvant,adjuvant,metastatic).Recommendations for HER2 and triplenegative subtypes are similar,whereas in luminal subtype there are various options of *** objective is to adapt guidelines to local context through relevant decision-makers,avoiding duplication of efforts and optimizing use or *** hope that these recommendations will help medical oncologists provide the best quality care to BC patients during the COVID-19 pandemic with information tailored to our healthcare *** To establish and adapt recommendations from those published by international scientific societies for BC *** The Peruvian Society of Medical Oncology developed a consensus and propose here a manuscript with recommendations for oncological medical treatment of BC during the COVID-19 *** Peruvian Society of Medical Oncology invited a panel of experts and opinion leaders on BC working in major health care systems around *** experts selected three international clin

关键词： Breast cancer COVID-19 Guidelines Recommendations Oncology Medical treatment

A Highly Sensitive In Situ Hybridization Assay For Hpv Detection In Mexican Women:Potential Marker Of Cervical Intraepithelial Neoplasia

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A Highly Sensitive In Situ Hybridization Assay For Hpv Detec...

Overexpression Of Protein P16ink4a As A Marker Of Squamous Intraepithelial Lesions Induced By High Risk Hpv Infection In Mexican Women

24th International Papillomavirus Conference and Clinical Workshop

作者： Luz del Carmen Alarcon-Romero Elba Reyes-maldonado Berenice Illades-Aguiar Eugenia Flores-Alfaro Gloria Fernondez-Tilapa Amalia Vences Velozquez Esther Ivonne Lepez-Bayghen Victor Gabriel Hernondez Chavez Marco Antonio Teran-Porcayo Escuela Nacional de Ciencias Biologicas IPNMexicoD.F.Facultad de Ciencias Quimico BiologicasUniversidad Autonoma de GuerreroChilpancingoGuerreroMexico Escuela Nacional de Ciencias Biologicas IPNMexicoD.F. Facultad de Ciencias Quimico Biologicas Universidad Autonoma de GuerreroChilpancingoGuerreroMexico Facultad de Ciencias Quimico Biologicas Universidad Autonoma de GuerreroChilpancingoGuerreroMexico Escuela Nacional de Ciencias Biologicas IPNMexicoD.F.Facultad de Ciencias Quimico BiologicasUniversidad Autonoma de GuerreroChilpancingoGuerreroMexico Escuela Nacional de Ciencias Biologicas IPNMexicoD.F.Facultad de Ciencias Quimico BiologicasUniversidad Autonoma de GuerreroChilpancingoGuerreroMexico Depatamento de Genetica y Biologia Molecular CIVESTAV-IPNMexicoD.F. Departamento de Anatomia patologica del Hospital de Cardiologia del Centro Medico Nacional Siglo XXI del IMSS MexicoD.F Instituto Estatal de Cancerologia“Dr arturo Beltran Ortega” AcapulcoGuerreroMexico

＜正＞Background:HPV infection is initiated with episomal virus,as state that is characterized by diffuse in situ hybridization（ISH） *** signal pattern correlates with the productive phenotype of HPV Integrated HPV has been found in association with invasive cervical carcinoma,and this event is characterized by a nuclear punctate ISH signal.

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Overexpression Of Protein P16ink4a As A Marker Of Squamous I...