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Journal of Surface Engineered materials and Advanced Technology 2020年第4期10卷 63-74页

作者： Yazmin Francisco Dulce medina miguel barron Joan reyes Pedro Adrian martinez Angel de Jesus morales Elizabeth Garfias Universidad Autónoma metropolitana Departamento de Materiales Ciencias Básicas e Ingeniería Reynosa Tamaulipas México Instituto Politécnico Nacional ESIQIE UPALM S/N Mexico City México

The synthesis of the thenoyltrifluoroacetone compound doped with terbium, dysprosium and europium encapsulated in a silica matrix (TTA:Tb:Dy:Eu@SiO2) were performed by the sol-gel method. The precursors to obtain the vitreous phase (SiO2) were: Tetraethylorthosilicate (TEOS, C8H2O4Si, 98%, Aldrich), and ethyl alcohol (CH3CH2OH, 99.5%, meyer), distilled water and 0.05 ml of hydrochloric acid (HCl, meyer). The sample with molar ratio 20:80 TTA:Tb:Dy:Eu@SiO2 has the best emission intensity. Thermogravimetric analysis (TGA) shown that silica encapsulated samples decompose at lower temperatures than pure TTA:Tb:Dy:Eu luminescent material. Fourier Transform Infrared (Ir-TF) shown the characteristic Si-O-Si bands that are presented at a wavelength of 1049, 853 and 440 cmǃ confirming that the luminescent material is encapsulated in a silica matrix, finally X-ray diffraction (XrD) shown that TTA:Tb:Dy:Eu@SiO2 composite is amorphous.

关键词： Synthesis Luminescence Composite Sol-Gel Terbium Dysprosium and Europium

Lithium recovery from Electrodes in Cellphone Batteries through the Leaching Process with Organic Agents Assisted by Ultrasound

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Journal of materials Science and Chemical Engineering 2018年第9期6卷 1-5页

作者： Pedro A. martínez Juan C. Orozco Alejandro Alonso rosa m. Luna miguel A. barron Dulce Y. medina Elizabeth Garfias-García División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Reynosa Tamaulipas México

The present work proposes a mean for recovery of metals used in current ion-lithium batteries, like lithium, cobalt and nickel, using organic agents and ultrasound instead of the more aggressive and less environment friendly method with sulfuric acid. This is especially useful in those countries that doesn’t have lithium deposits and have a growing demand of such batteries, reducing the economic loss this represents. During the process, variables such as temperature, leaching agent concentration and ultrasound frequency were modified, using concentrations of 0.5 m (molar), 1 m and 1.5 m of sodium citrate, temperatures of 25°C, 55°C and 60°C and also ultrasound frequencies of 20 KHz, 30 KHz and 40 KHz. It was found that the best combination of these variables that yielded the most quantity of the desired metal was 0.5 m concentration for both lithium and nickel, while using 60°C and no ultrasound with Li and 55°C and 40 KHz for Ni. For Co the best variables discovered were 1.5 molar concentration, 60°C and 40 KHz.

关键词： Lithium Leaching Organic Agents Ion-Lithium Batteries Ultrasound Leaching Sodium Citrate

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父爱花园

新东方英语（中英文版） 2009年第6期 36-38页

作者： James Douglas barron 赵娜

少不经事、青春叛逆的我们对于父辈的教导总会有一种天生的排斥，我们把他们的肺腑之言当成耳旁风，把他们多年的人生经验看做老“古董”，我们发誓长大后决不会和他们做同样的事、走同样的路。却不料，经年累月间，父辈的那些教诲竟已... 详细信息

少不经事、青春叛逆的我们对于父辈的教导总会有一种天生的排斥，我们把他们的肺腑之言当成耳旁风，把他们多年的人生经验看做老“古董”，我们发誓长大后决不会和他们做同样的事、走同样的路。却不料，经年累月间，父辈的那些教诲竟已在我们的心中生了根，发了芽，变成了让我们受用一生的智慧，而我们的生活也因这些智慧变得更加完满……

关键词：花园父爱人生经验父辈智慧

red, White and Blue Light Emission from Europium Doped Al2O3 Confined into a Silica matrix

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Open Journal of Applied Sciences 2018年第8期8卷 338-345页

作者： Joan reyes Dulce Y. medina miriam Aguilar miguel A. barron Elizabeth Garfias Angel de Jesus morales Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana-Azcapotzalco Reynosa México Instituto Politécnico Nacional ESIQIE Mexico City México

The main drawbacks of fluorescent activated lanthanide luminescent materials in practical optoelectronic applications are the high cost of raw material and the limitation of a specific color depending on the lanthanide ion. In this work, the synthesis of red, white and blue light emitting composite powders of Al2O3:Eu3+@SiO2 were successfully synthesized by the hydrolysis and condensation reactions of TEOS as the raw precursor of silica matrix on the Al2O3:Eu3+ surface. With the aim to change the CIE coordinates different weight ratios of Al2O3:Eu3+/SiO2 powders from 13Al/87Si to 5Al/95Si were prepared. Besides, various excitation wavelength from 280 to 340 nm was used in order to change the ratio intensity;Ired/Iblue, between the red emission coming from the 5D0→7F2 transition of Eu3+ ions and the blue band of silica matrix. Chemical evolution of the hydrolysis and condensation reaction of TEOS were conducted by FTIr spectroscopy. The results indicate that from 500°C a complete TEOS to SiO2 transformation is carried out.

关键词： Luminescent Lanthanide Luminescence White Emission Aluminium Oxide

mathematical modelling of Einstein’s rate Equations for Zinc Phosphate Glass with Er<sup>3+</sup>-Yb<sup>3+</sup>

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Open Journal of Applied Sciences 2021年第9期11卷 1038-1045页

作者： Frida Lissete Flores rivera Grethell Georgina Pérez-Sánchez miguel Angel barron-meza Joan reyes miranda Dulce Yolotzin medina Velázquez Division of Basic Science and Engineering Universidad Autónoma Metropolitana México City México

There is a constant growth in the demand of data information transmission capacity, that is, more and more people send data, voice, video signals, among others, through communications networks. Due to the above there is great interest in improving network devices, such as optical amplifiers, which must cover a large bandwidth and generate greater gain than those currently available. For this reason in this work a computational simulation for a Quasi-system was carried out mily:"">three energy levels of Erbium and Ytterbium varying their concentrations and proving that they are optimal candidates in a zinc phosphate matrix as this type of glass contains properties such as, high transparency, low melting point, high thermal stability, high gain density due to high solubility, low refractive index and low dispersion, which makes them optimal as signal amplifiers. The results confirm that by increasing the doping of the Erbium ion the gain of the amplifier decreases, contrary to the Ytterbium ion that by increasing the doping the gain of the amplifier increases.

关键词： Optical Telecommunications rare Earths Doping Optical Amplifier Gain

rare-Earth Doped GdVO₄ by Sol-Gel method: Structural and Luminescence Properties

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World Journal of Engineering and Technology 2022年第4期10卷 907-922页

作者： D. Y. medina-Velázquez A. D. J. morales-ramírez A. A. morales-Hernández B. Gonzalez L. ramírez-García E. Garfías-García J. Oliva C. r. Garcia J. reyes-miranda m. A. barron E. Osorio-de-la-rosa Universidad Autónoma metropolitana-Azcapotzalco Ciencias Básicas e Ingeniería Reynosa México Instituto Politécnico Nacional CIITEC IPN Cerrada de CECATI S/N Col. México City México Instituto Politécnico Nacional ESIQIE IPN México City México CONACyT-División de materiales Avanzados Instituto Potosino de Investigación Científica y Tecnológica A. C. San Luis Potosí México Facultad de Ciencias Físico matemáticas Universidad Autónoma de Coahuila Edif. A Unidad Camporredondo Saltillo México Comonfort Col. Del Bosque. C.P. 77019 Chetumal Quintana Roo México.6 CONACYT-Universidad Autónoma del Estado de Quintana Roo Boulevard Bahía s/n esq. Ignacio Chetumal México

rare earths have been extensively developed in recent years, however, new hosts allow high excitation and emission efficiency, in this sense, gadolinium vanadate has been extensively studied and in previous works it has been widely used in down conversion systems. Because of the strong absorption of the VO4 groups and efficient energy transfer from GdVO4 to lanthanide ions, in this work its up-conversion properties were studied when is co-doped with Yb3+, X3+ where X = Tm, Er and Ho. The powders synthesized presented a high crystallinity and a rounded morphology and exhibit a high luminescence when are excited with Ir radiation.

关键词： Gadolinium rare Earths Up Convertion

Copper Oxide Inked with Dye Obtained from the Lactarius Indigo Fungus for Energy Production

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Journal of materials Science and Chemical Engineering 2022年第11期10卷 36-51页

作者： Abigail Bautista Castañeda maria Guadalupe montes De Oca Dulce Yolotzin medina Velazquez Jorge Iván Aldana González Pedro Adrian martinez montolla Joan reyes miranda miguel Angel barron Universidad Autónoma metropolitana Departamento de Materiales Ciencias Básicas e Ingeniería Reynosa Tamaulipas México Instituto Politécnico Nacional ESIQIE UPALM S/N Col. Mexico City México

The results obtained from the characterization of a copper deposit on indium doped tin oxide (ITO), inked with natural dye extracted from the Lactarius indigo fungus, for use in Gratzel type solar cells are reported. An electrolyte composed of 0.1 m HNO3 and 0.5 m CuSO4 was used, this solution was prepared for copper deposits on the ITO. Cyclic voltammetry was performed at different scan rates to obtain the reduction zone for deposition between potentials of ?100 to ?500 mV. The dye was obtained from the indigo Lactarius fungus from maceration, once the inked deposits were obtained, characterizations were performed, the initial test was to obtain the Ultraviolet-Visible (UV-visible) of the pure dye, and later the same test was performed on the inked oxide. Electrochemical Impedance Spectroscopy (EIS) was performed on the samples, as well as Infrared Spectroscopy (FTIr) and Scanning Electron microscopy (SEm), to characterize the material properties for its application.

关键词： Copper Oxide Ink Dye Energy Production Indigo milk mushroom

Blue-red Tuning Emission of ZnO: Europium Quantum Dots with Different Excitation Wavelengths

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Open Journal of Applied Sciences 2018年第10期8卷 441-445页

作者： Primitivo Ortiz maldonado Ana K. Chavez-Alvarado Francisco J. rodríguez Gutierrez Joan reyes miranda Dulce Y. medina Velazquez miguel A. barron Elizabeth Garfias García Universidad Autónoma Intercultural de Sinaloa El Fuerte México División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Reynosa Tamaulipas México

Optoelectronic applications require the development of new fluorescent and efficient luminescent materials, free of toxicity, low in cost, and easy to produce. In this way the synthesis of zinc-oxide (ZnO) quantum dots (QDs) has recently received special attention due to their good optical, electrical and chemical properties with low production costs and blue light emission. In this work ZnO QDs were successfully doped with europium in order to obtain a tunable emission luminescence from blue emission of ZnO to red emission of europium as a function of wavelength excitation. results show an efficient blue to red tuning when the excitation wavelength was changed from 317 nm to 395 nm, respectively. This opens the possibility of having new optical devices to produce different color emission using the same material.

关键词： Chromaticity Diagram Emission Spectra Europium Luminescence red-Blue Tuning ZnO Quantum Dots White Light

Performance and calibration of quark/gluon-jet taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.J. Abicht S.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.S. Acharya C. Adam Bourdarios L. Adamczyk S.V. Addepalli m.J. Addison J. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik m.N. Agaras J. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W.S. Ahmed S. Ahuja X. Ai G. Aielli A. Aikot m. Ait Tamlihat B. Aitbenchikh I. Aizenberg m. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi J. Albert P. Albicocco G.L. Albouy S. Alderweireldt m. Aleksa I.N. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi m. Algren m. Alhroob B. Ali H.m.J. Ali S. Ali S.W. Alibocus m. Aliev G. Alimonti W. Alkakhi C. Allaire B.m.m. Allbrooke J.F. Allen C.A. Allendes Flores P.P. Allport A. Aloisio F. Alonso C. Alpigiani m. Alvarez Estevez A. Alvarez Fernandez m. Alves Cardoso m.G. Alviggi m. Aly Y. Amaral Coutinho A. Ambler C. Amelung m. Amerl C.G. Ames D. Amidei S.P. Amor Dos Santos K.r. Amos V. Ananiev C. Anastopoulos T. Andeen J.K. Anders S.Y. Andrean A. Andreazza S. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel m.T. Anthony E. Antipov m. Antonelli F. Anulli m. Aoki T. Aoki J.A. Aparisi Pozo m.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal S.J. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena J-F. Arguin S. Argyropoulos J.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai S. Asai N.A. Asbah J. Assahsah K. Assamagan r. Astalos S. Atashi r.J. Atkin m. Atkinson H. Atmani P.A. Atmasiddha K. Augsten S. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia m. Bahmani A.J. Bailey V.r. Bailey J.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan r. Balasubramanian E.m. Baldin P. Balek E. Ballabene F. Balli L.m. Baltes W.K. Balunas J. Balz E. Banas m. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak m. Barakat E.L. Barberio D. Barberis m. Barbero m.Z. Barel K.N. Barends T. Barillari m-S. Barisits T. Barklow P. Baron D.A. Baron mo The ATLAS Collaboration

The identification of jets originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large Hadron Collider,as Standard model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced *** paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAS Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAS *** taggers with high performances in rejecting jets from gluon over jets from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the jet *** in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAS JET QUArK GLUON TAGGING

红细胞输注与儿童重症监护病房院内感染的相关性研究

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中国小儿急救医学 2010年第4期 291-291页

作者： White m barron J Gombein J 杨明首都医科大学附属北京儿童医院

目的成人研究发现输红细胞与院内感染相关。本研究旨在探讨输红细胞是否同样与儿童重症监护病房(PICU)院内感染相关,淋巴细胞计数减少是否为可能的机制之一。设计历史性对列研究。场所单中心,一所大学附属儿童医院含内外科的综合性PIC... 详细信息

目的成人研究发现输红细胞与院内感染相关。本研究旨在探讨输红细胞是否同样与儿童重症监护病房(PICU)院内感染相关,淋巴细胞计数减少是否为可能的机制之一。设计历史性对列研究。场所单中心,一所大学附属儿童医院含内外科的综合性PICU。对象 2005年1月1日至7月3日PICU收住的18岁以下患儿。干预无。测量指标和主要结果院内感染(呼吸系统感染、尿路感染和血流感染)为主要观察指标,输红细胞后14 d内发生者被认为是输血后感染。在209例纳入研究的患儿中,32例(15%)发生院内感染,45例(22%)输过红细胞。发生院内感染的患儿输红细胞的比率显著高于无院内感染者(Or 18.0,95%CI 7.6～45.9,Pr 3.73,95%CI 1.19～11.85,P=0.023)。输血患儿淋巴细胞绝对数较未输血者低(1 605/μl vs 2 054/μl,P=0.041),但白细胞总数相当(10.4×10~3/μl vs 11.4×10~3/μl,P=0.52)。结论 PICU输红细胞的患儿发生院内感染的风险增加。

关键词：红细胞输注细菌感染儿童重症监护病房淋巴细胞计数回顾性研究疾病严重程度指数