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Cell-Phone Recycling by Solvolysis for Recovery of Metals

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Journal of Materials Science and chemical Engineering 2015年第1期3卷 52-57页

作者： Lorena Eugenia Sánchez Cadena Zeferino Gamino Arroyo Mario Alberto González lara Q.Demetrio quiroz Departamento de Ingeniería Civil Universidad de GuanajuatoDIAv.Juárez 77CP 36000GuanajuatoGto.México Departamento de Ingeniería Química Universidad de GuanajuatoDCNyENoria Alta s/nCP 36050GuanajuatoGto.México

Mobile phones represent a significant and growing problem with respect to electrical waste and electronic equipment (WEEE). Nevertheless, they are perhaps one of the most valuable electronic products, since they are an important resource for the recovery of metals in terms of mass and volume. In this research a chemical recycling of mobile phones by solvolysis was investigated. The processing was performed by comminution in a hammer mill followed by screening to obtain mesh-4 sized flakes. Flakes were subjected to solvolysis. Different reaction conditions were tested. A reaction time between 2 - 7 hours and a temperature between 150°C - 300°C were the optimum conditions to dissolve the polymer contained in mobile phones. Metals were separated by filtration. chemical analyses (ATR FT-IR, UV) were carried out on the solvent and the mobile phone flakes before and after solvolysis. A SEM study was carried out, before and after solvolysis, but only to the mobile phone flakes. Thermal transitions of mobile phone flakes were determined by DSC. chemical results showed that some aromatic species migrate from mobile phones flakes to the solvent, due to the solvolysis reaction. Thermal analysis showed that the Tg, (glass transition temperature) of mobile phone flakes after solvolysis was different to Tg of the polymer before solvolysis, this is due to chemical changes in the molecule. A comparative SEM study revealed that, after solvolysis, the polymer contained in mobile phone flakes is more elastomeric. After solvolysis, solvent was recovered by means of a rotatory evaporator, so that it can be used again. The results obtained in this research showed that solvolysis is an alternative for metal recovery from mobile phones.

关键词： Cell-Phones Solvolysis Recycling

The effect of transcorneal electrical stimulation in visual acuity: Retinitis pigmentosa

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Journal of Biomedical Science and Engineering 2013年第10期6卷 1-7页

作者： Daniel Robles-Camarillo Luis Nino-de-Rivera Jessica Lopez-Miranda Félix Gil-Carrasco Hugo quiroz-Mercado Department of Telematic Engineering Universidad Politécnica de PachucaZempoalaMexico Graduate Department ESIME UCInstituto Politécnico NacionalMéxico CityMéxico Retina Service Asociación Para Evitar la Ceguera en MéxicoMéxico CityMéxico Ophthalmology Service Denver Health Medical CenterDenverUSA

Transcorneal Electrical Stimulation (TES) was applied to a group of volunteer patients suffering from Retinitis Pigmentosa (RP), in order to investigate the effect of TES in Visual Acuity (VA). 28 partial blind patients with diagnosis of classic RP, Usher syndrome I and/or II were stimulated transcornealy, during a period of 52 weeks using a non conventional waveform, only in the lowest visually capable eye. The proposed waveform has been modeled from the natural response of human retina and delivered by means of an adaptive generator designed and built for tissue stimulation. Statistical results show the improvement of average VA or at least the contention of the disease natural progress. Categorized analysis of results indicates the same effect that if the age of patients, time since diagnosis and genetic disorder variation (classic RP, Usher syndrome I and/or II) are considered, in this case clinical and electrophysiological follow-up parameters were statistically analyzed in order to know the effect of TES. General results yield an improvement of 48.15% in the average of VA for stimulated eyes against an average degreasing of -8.06% in the same scale, with respect to their basal condition before the start of the experiment.

关键词： Transcorneal Electrical Stimulation Retinitis Pigmentosa Adaptive Waveform Model Visual Acuity

The Utility of Endovaginal Ultrasound in the Design of a Sacrospinous Ligament Anchoring Device in Patients with and without Pelvic Organ Prolapse

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Open Journal of Obstetrics and Gynecology 2019年第8期9卷 1103-1113页

作者： Jonia Alshiek Qi Wei Lieschen H. quiroz Mikio A. Nihira Menahem Neuman S. Abbas Shobeiri Department of Obstetrics & Gynecology INOVA Women’s Hospital Falls Church USA Department of Obstetrics and Gynecology Hillel Yafe Medical Center Hadera Israel Department of Bioengineering George Mason University Fairfax USA Department of Obstetrics & Gynecology The University of Oklahoma Health Sciences Center Oklahoma City USA Department of Obstetrics & Gynecology The University of California Riverside USA Urogynecology Women Health Division Galilee MC Nahariya Faculty of Medicine Bar Ilan University Ramat Gan Israel

Objective: To determine whether endovaginal ultrasound is a reliable measure in visualization of the sacrospinous ligament among women with prolapse versus women without prolapse, and thus might be clinically applicable in the design of an ultrasound-guided device for performing sacrospinous ligament anchor placement as a treatment for pelvic organ prolapse. Methods: In the first phase of this study we performed a sacrospinous anchor placement in four normal fresh-frozen female pelves. Afterwards, an endovaginal ultrasound was performed to visualize the anchor localization which was validated by dissection of the cadaveric pelves. In the second phase of the study: two groups of volunteer females with and without pelvic organ prolapsed (POP-group, vs NON-POP group) were evaluated by endovaginal ultrasound to localize the sacrospinous ligament. Results: Cadaveric dissection demonstrated accurate anchor placement into the 8/8 sacrospinous ligament. We performed endovaginal ultrasound in a total of 17 N-POP and 10 (POP) patients. Among the N-POP group, the right and left ischial spines were visible in 6/17 (35%) and (6/17) 35% vs 0/10 (0%) for both right and left sides in POP group (p = 0.008). The right sacrospinous ligament was visualized in 4/17 (23%) N-POP subjects and 0/10 POP subjects (p = 0.27) and the left sacrospinous ligament was visualized in 7/17 (41%) N-POP subjects and 2/10 POP subjects (p = 0.48). Conclusions: Sacrospinous ligament and the ischial spines couldn’t be reliably visualized among women with or without pelvic organ prolapse using endovaginal ultrasound, although the structures are visualized more in some of the non-prolapsed women. The sacrospinous anchoring device demonstrated accurate placement by cadaveric dissections.

关键词： Sacrospinous Ligament Pelvic Organ Prolapse Endovaginal Ultrasound

Degradation of Gesaprim Herbicide by Heterogeneous Photocatalysis Using Fe-Doped TiO2

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International Journal of Geosciences 2011年第4期2卷 669-675页

作者： Noemí A. quiroz Dulce J. R. Gutierrez Susana S. Martínez Cristina L. Bahena 不详

Fe-doped TiO2 was prepared by the sol gel method and characterized by X-ray diffraction. All the Fe-doped TiO2 were composed of an anatase crystal form. The activity of the Fe-doped TiO2 for the degradation of the gesaprim commercial herbicide (which contains atrazine as active compound and formulating agents) was studied by varying the iron content during UV (15 W), visible light and solar irradiations. The visible light came from commercial saving energy lamps (13, 15 and 20 Watts). The gesaprim degradation rate depended on the iron content in the photo catalyst. The Fe-doped TiO2 (0.5% by weight of TiO2) showed higher TOC removal under visible light and was more active than the undoped TiO2 photo catalyst under the light irradiation sources tested. Over 90% of chemical oxygen demand abatement was achieved with both UV and visible light but less time was required to decrease the chemical oxygen demand content by using the catalyst doped with iron at 0.5% under visible light. It was observed that the degradation of gesaprim increased by increasing the iron content in the catalyst under visible light.

关键词： Atrazine Iron Doped TiO2 Solar Irradiation Visible Light Irradiation

Experiment and Modeling of Low Coverage Uptake of N2 and 02 on H-Clinoptilolite Zeolite from Tehuacan, Puebla, Mexico

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Journal of chemistry and chemical Engineering 2014年第1期8卷 1-10页

作者： Miguel Angel Hemández karla quiroz Fernando Rojas: Roberto Portillo Martha Alicia Salgado Fernando Hernándezl Antonio Rivera chemistry Departament Metropolitan Autonomous University-Iztapalapa Mdxico 09340 México Faculty of chemistry Autonomous University of Puebla Puebla 72570 México chemistry Center Autonomous University of Puebla Puebla 72570 México Microbiology Center Autonomous University of Puebla Puebla 72570 México Zeolites Research Department and Postgrade of Agroecology Autonomous University of Puebla Puebla 725 70 México

Adsorption isotherms of N2 and 02 on dealuminated clinoptilolite zeolites were measured by the inverse gas chromatography method at zero-coverage. This type of microporous solids such as natural （CLINA） and dealuminated clinoptilolite zeolites （CLIDA1-CLIDA5） were conditioned by means of acid treatment of the natural zeolitic precursor （CLINA） with HCI at different concentration. Adsorption of selected gases （N2 and 02） on clinoptilolite zeolites were studied in the temperature range from 398 K to 498 K. The langmuir adsorption model was found to approximately fit the gases adsorption data, within the selected temperature range. The uptake amount of these gases by the diverse adsorbents was temperature dependent. Additionally, the energies of interaction between of these gases with clinoptilolite microporous walls were realized from the evaluation of the isosteric heats of adsorption （qst）. These isosteric heats were found to obey in the following decreasing order： qst （N2）： CLIDA1 〉 CLIDA3 〉 CLIDA2 〉 CLIDA4 〉 CLIDA5 〉 CLINA; while qst （02）： CLIDA3 〉 CLIDA2 〉 CL1DA1 〉 CLIDA5 〉 CLIDA4 〉 CLINA.

关键词： Zeolite clinoptilolite sorption langmuir isosteric heats.

Bright Red Luminescence and Structural Properties of Eu<sup>3+</sup>Ion Doped ZnO by Solution Combustion Technique

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World Journal of Condensed Matter Physics 2014年第4期4卷 227-234页

作者： Sebastián López-Romero María Jesús quiroz-Jiménez Manuel Hipólito García Alfredo Aguilar-Castillo Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de México Circuito Interior S/N Ciudad Universitaria México México D.F. México

Pure, and Europium ion doped Zinc oxide nanocrystals (ZnO:Eu3+) were synthesized by a solution combustion technique. The X-ray diffraction patterns (XRD) reveals the existence of the Eu2O3 phase. From the results of both, X-ray diffraction and photoluminescence spectra (PL) reveal that Eu3+ ions successfully substitute for Zn2+ ions in the ZnO lattice, moreover, when the amount of doped Europium was varied, this changes are showed in changes in the luminescence intensity. The PL is broad and a set of colors was emitted which originates from ZnO and the intra 4f transitions of Eu3+ ions. The existence of the Zn-O, Eu3+-O and O1s bonding energies were confirmed by X-ray photoelectron spectroscopy (XPS) technique. The samples morphology was registered by a scanning electron microscopy (SEM) technique, and reveals that Europium ions are present on the surface of the ZnO nanocrystals.

关键词： ZnO Europium Ion Solution Combustion Photoluminescence

Gallbladder plication as a rare complication of endoscopic sleeve gastroplasty:A case report

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World Journal of Gastrointestinal Endoscopy 2023年第10期15卷 629-633页

作者： Cesar D quiroz Guadarrama Luis Andres Saenz Romero Eric Misael Saucedo Moreno Martín E Rojano Rodríguez Obesity Clinic and Bariatric Surgery Dr.Manuel Gea González General HospitalMéxico 14080Mexico

Endoscopic sleeve gastroplasty(ESG)is a minimally invasive procedure used in the treatment of obesity,with a complication rate of less than 2%of *** have been only two reported cases worldwide of gallbladder injuries as a major complication of *** SUMMARY We present the case of a 34-year-old patient who developed a complication after *** patient experienced epigastric and right hypochondrium pain 12 h after the procedure,and a positive Murphy’s sign was identified on physical *** results showed a leukocyte count of 17×10^(3)/μL,and computed tomography indicated the presence of free fluid in the pelvic cavity and perihepatic recesses as well as a possible suture in the wall of the Hartmann’s pouch toward the anterior surface of the stomach.A diagnostic laparoscopy was performed,revealing plication of the Hartmann’s pouch wall to the anterior stomach *** cholecystectomy and lavage were carried *** patient had a stable recovery and was discharged 72 h after surgery,tolerating oral *** Gallbladder plication should be suspected if signs and symptoms consistent with acute cholecystitis occur after ESG.

关键词： Gastroplasty Bariatric surgery Complication Endoscopy Case report

Estimation of Human Movements via Quaternion

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通讯和计算机（中英文版） 2013年第5期10卷 693-701页

作者： Bernardino Benito Salmeron-quiroz Jose Fermi Guerrero-Castellanos Cesar Femando Mendez-Barrios Gerardo Villegas-Medina Hector Mendez-Azua SEPI ESIME UA National Polytechnic Institute (I.P.N.) Azcapotzalco 02250 Mexico Mechatronics Department Autonomous University of Puebla (BUAP) Puebla 72592 Mexico Faculty of Engineering Autonomous University of San Luis Potosi (UASLP) San Luis Potosi 78290 Mexico

Estimation of the Attitude in an Industrial Robot： An Unit Quaternion Approach

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通讯和计算机（中英文版） 2012年第11期9卷 1287-1292页

作者： Salmeron-quiroz Bemardino Benito Guerrero-Castellanos Jose Fermi Villegas-Medina Gerardo Rodriguez-Paredes Salvador Antonio lam-Farias Luis Faculty of Engineering Autonomous University of San Luis Potosi (UASLP) zipcode 78290 San Luis PotosL Mexico Mechatronics Department Autonomous University of Puebla (BUAP) Valsequillo Boulevard zipcode 72592 Puebla Mexico National Polytechnic Institute (IPN- SEPI ESIME UA) Av. De la Granjas 682 Azcapotzalco zipcode 02250 Mexico City Motors Department Volkswagen Mexico Mexico-Puebla Km 116 Puebla zipcode 72700 Mexico