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射孔新技术——高性能射孔模型

国外测井技术 2017年第1期38卷 61-71页

作者： Carlos Baumann Alfredo Fayard Brenden Grove Jeremy Harvey Wenbo Yang Amit Govil Andy Martin Roberto Franco Mendez Garcia arturo ramirez rodriquez Jock Munro Cesar Velez Terrazas Lang Zhan 斯伦贝谢公司

爆炸聚能射孔是一种在油气井中射穿套管来形成井筒和套管外岩石之间通道的技术。服务公司通过地面试验，将聚能射孔弹射入无应力水泥靶中，以了解其在已知条件下的射孔性能。在认识到模拟程序可能无法正确预测井下聚能射孔弹的性能后，... 详细信息

爆炸聚能射孔是一种在油气井中射穿套管来形成井筒和套管外岩石之间通道的技术。服务公司通过地面试验，将聚能射孔弹射入无应力水泥靶中，以了解其在已知条件下的射孔性能。在认识到模拟程序可能无法正确预测井下聚能射孔弹的性能后，斯伦贝谢的科研人员开发出了可精确计算射孔深度、射孔效率和系统动态响应的软件，并以此来优化在高应力岩石中聚能射孔弹的性能。

关键词：射孔弹射孔枪模型分析井下条件射孔效率射孔密度作业者套管射孔预测模型渗透率

Insecticidal Activity and Physicochemical Characterization of Nanoparticles from Foliar Extract of Capsicum chinense

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Journal of Renewable Materials 2023年第11期11卷 3933-3943页

作者： Arnoldo E.Alfaro-Corres Daniel Gonzalez-Mendoza Esau Ruiz-Sanchez Carlos Ail-Catzin Benjamin Valdez-Salas Federico Gutierrez-Miceli arturo Reyes-ramirez Jacques Fils Pierre Division of Postgraduate Studies and Research Tecnologico Nacional de MéxicoCampus ConkalConkalYucatán97345Mexico Institute of Agricultural Sciences Universidad Autonoma de Baja CaliforniaEjido Nuevo LeonMexicaliBaja California21705Mexico Instituto de Ingeniería Universidad Autónoma de Baja CaliforniaMexicaliBaja California21100Mexico Division of Postgraduate Studies and Research Tecnologico Nacional de MexicoCampus Tuxtla GutierrezTuxtla GutierrezChiapas29050Mexico

This work was carried out to evaluate the insecticidal effect of mono,bi and trimetallic nanoparticles(NPs)from leaf extract of habanero pepper(Capsicum chinense Jacq.)on the red flour beetle(Tribolium castaneum herbst.)and cotton mealybug(Phenacoccus solenopsis Tinsley).The results showed that Cu NPs,Cu/Mn NPs and Zn/Cu NPs had high insecticidal effect against T.castaneum(63%-80% mortality after 96 h).The Cu NPs and Zn/Cu NPs showed also insecticidal effect against P.solenopsis,but to a lesser extent(20%–28% after 96 h).With regards to the physicochemical characterization,Cu NPs had a zeta potential of 21.1 mV,whereas Cu/Mn NPs and Zn/Cu NPs exhibited zeta potentials of 200 mV.The polydispersity index(PDI)values for Cu NPs,Cu/Mn NPs,and Zn/Cu NPs were 10.1,29.16,and 14.34,respectively.The TF-IR spectra of the NPs varied from 600 to 4000 cm−1.The EDX weight percentages showed the presence of Cu(0.29%–2.4%),Mn(1.4%),and Zn(2.6%)in Cu/Mn NPs and Zn/Cu NPs,respectively.

关键词： Phytonanoparticles botanical insecticide pest control agronanotechnology

Robust flat filtering DSP based control of the boost converter

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Control Theory and Technology 2016年第3期14卷 224-236页

作者： Hebertt SIRA-ramirez arturo HERNANDEZ-MENDEZ Jesus LINARES-FLORES Alberto LUVIANO-JUAREZ Department of Hectrical Engineering Mechatronics Section ClNVESTAV-IPN Av. IPN No. 2508 Col. San Pedro Zacatenco 07360 D.F. Mexico Mexico Universidad Tecnologica de la Mixteca Carretera a Acatlima Kin. 2.5 Huajuapan de Leon Oaxaca Mexico UPIITA-IPN D.F. Mexico Mexico

The article deals with the design and implementation of a flat filter tracking digital controller for a boost DC-DC power converter. A highly perturbed switched boost converter circuit is shown to be efficiently controlled, in a trajectory tracking task for its non-minimum phase output, by means of a suitable linear filter, here addressed as a flat filter. Flat filtering is a natural robust version of generalized proportional integral control （GPIC） by which the effects of arbitrary time varying exogenous disturbances, unknown endogenous nonlinearities and un-modeled dynamics can be jointly attenuated in a conceptually similar fashion to observer-based active disturbance rejection control （ADRC） and algebraic identification based model free control （MFC） but： a） without using extended state observers and b） respecting the original system order in a time-varying simplified model while avoiding algebraic estimation techniques. The proposed control technique based on the TMS320F28335 digital signal processor chip is tested by means of realistic simulations and experimental setup.

关键词： Flat filter DSP-implementation boost converter

Toxic anterior segment syndrome after implantation of phakic implantable collamer lens

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International Journal of Ophthalmology(English edition) 2019年第1期12卷 175-177页

作者： Erick Hernandez-Bogantes arturo ramirez-Miranda Andrew Olivo-Payne Alexandra Abdala-Figuerola Alejandro Navas Enrique O.Graue-Hernandez Department of Cornea and Refractive Surgery Conde of Valenciana Foundation Institute of Ophthalmology Ocular Center Department of Cornea and Refractive Surgery Atlantic Laser Unit Center

Dear Editor,Iam Dr.Erick Hemandez-Bogantes from the Department of Cornea and Refractive Surgery,Conde of Valenciana Foundation Institute of Ophthalmology,Mexico City,Mexico. The purpose of this letter is to present 3 cases (6 eyes)of toxic anterior segment syndrome (TASS)after same day implantation of a posterior phakic implantable collamer lens (ICL;V4c Visian ICL;STAAR Surgical,Monrovia,CA,USA).

关键词： Iam Dr.Erick Hemandez-Bogantes Valenciana Foundation implantation

Trans-epithelial accelerated corneal cross-linking for keratoconus in children

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International Journal of Ophthalmology(English edition) 2017年第12期10卷 1919-1921页

作者： Andrew Olivo-Payne Juan Carlos Serna-Ojeda Erick Hernandez-Bogantes Alexandra Abdala-Figuerola Lueero Pedro-Aguilar Alejandro Liehtinger arturo ramirez-Miranda Alejandro Navas Enrique O. Graue-Hernandez department of cornea and refractive surgery institute of ophthalmology"conde de valenciana"Cuauhtemoc 06800Mexico CityMexico

The aim of the study is to evaluate the safety and effi cacy of trans-epithelial accelerated corneal cross-linking（TE-ACXL） in children with progressive keratoconus.Retrospective,case-series of 23 eyes of 14 children who underwent TE-ACXL.Evaluations were performed at baseline and 1,3,6,12 and 18 mo postoperatively.Mean follow-up time of 23.82±3.15 mo and mean age was 13.7±1.4 y（range 11 to 16 y）.Mean preoperative uncorrected distance visual acuity changed from 0.92±0.45 log MAR（20/160） to 0.71±0.40 log MAR（20/100）（P=0.001）.Mean keratometry（Km） changed from 53.87± 6.03 to 53.00±5.81（P=0.001）.Pachymetry did not have significant changes at last follow-up（P=0.30）.The mean preoperative sphere was-5.58±2.48 and-4.89±4.66 D（P=0.11） at last follow-up;refractive cylinder from-5.58±2.48 to-5.02±2.23（P=0.046）.In conclusion,tomographic and refractive stability are shown in over 91% of eyes with pediatric progressive keratoconus who underwent TE-ACXL.

关键词： corneal cross-linking keratoconus acceleratedcross-linking pediatric keratoconus

Keratoconus therapeutics advances

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World Journal of Ophthalmology 2013年第3期3卷 20-31页

作者： Martha Jaimes arturo ramirez-Miranda Enrique O Graue-Hernández Alejandro Navas Department of Cornea and Refractive Surgery Institute of Ophthalmology "Conde de Valenciana"06800 Mexico City Mexico

Keratoconus is a progressive, usually bilateral disease of the cornea that significantly diminishes visual acuity, secondary to a progressive corneal deformity which is characterized by corneal thinning, variable degrees of irregular astigmatism and specific abnormal topographic patterns. Normally it initiates during puberty and is progressive until the third or fourth decade of life, when normally the progression rate is diminished or waned. There are multiple scales to clinically classify keratoconus. One of the most commonly used is Amsler-Krumeich and recently with the development of morphometric and aberrometric techniques, additional scales have been created that allow keratoconus to be classified according to its severity. Despite certain etiology of keratoconus remains unknown, current treatment options are available in patients with ectatic corneas and they vary depending on the severity of the disease and they include spectacles, contact lenses, intrastromal rings, keratoplasty both penetrant or lamellar, cross-linking, refractive lens exchange withintraocular lens implant, phakic intraocular lenses and the combination of these alternatives. Some authors have been using excimer laser in patients with keratoconus but the safety of the procedure is controversial. Currently, the techniques for the management of keratoconus can be classified in 3 types: corneal strengthening techniques, optical optimization techniques and combined techniques.

关键词： Keratoconus Treatment Management Corneal ectasia Therapeutics

Effect of the thin cell layer technique in the induction of somatic embryos in Pinus patula Schl. et Cham

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Journal of Forestry Research 2019年第4期30卷 1535-1539页

作者： Marco A.ramirez-Mosqueda Lourdes G.Iglesias-Andreu arturo A.Armas-Silva Esmeralda J.Cruz-Gutierrez Jose F.de la Torre-Sanchez Otto R.Leyva-Ovalle Carlos M.Galan-Paez Instituto de Biotecnologfa y Ecologfa Aplicada(INBIOTECA) Universidad Veracruzana.Av.de las Culturas Veracruzanas No.101Campus para la Culturalas Artes y el DeporteCol.Emiliano ZapataC.P.91090 XalapaVeracruzMexico Centro Nacional de Recursos Geneticos-INIFAP Boulevard de la Biodiversidad No.400 Rancho las CrucesC.P.47600 Tepatitlan de MorelosJaliscoMexico Facultad de Ciencias Bioldgicas y Agropecuarias Region Cordoba-Orizaba Universidad VeracruzanaC.P.94945 Amatlan de los ReyesVeracruzMexico

Pinus patula is a species commonly used for reforestation in Mexico.However,efficient methods for the mass production seedlings are required.Micropropagation particularly by somatic embryogenesis provides an option for the rapid multiplication of high-quality,genetically improved material.This study induces somatic embryogenesis in this species using the thin cell layer(TCL)technique.Two sources of explants(complete immature embryos;lTCL segments from immature embryos)were evaluated.The efficiency of TCL from longitudinal sections[lTCL]and transverse[tTCL]was evaluated.The results show using thin cell layers from immature embryos cultivated in 16 light/8 dark hours achieves induction of somatic embryos.A higher percentage of embryogenic callus was obtained when tTCL segments were used as an explant source.These results produced somatic embryos from tTCL segments of an immature embryo without germinating the seed,making the process more time efficient.In addition,this technique can be used to generate somatic embryogenesis in forest species that have low germination rates.

关键词： Pinus patula Somatic embryos Micropropagation Thin cell layer Maturation

Symmetric Solutions of a Nonlinear Elliptic Problem with Neumann Boundary Condition

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Applied Mathematics 2012年第11期3卷 1686-1688页

作者： Ana Magnolia Marin ramirez Ruben Dario Ortiz Ortiz Joel arturo Rodriguez Ceballos Group of Waves Program of Mathematics Faculty of Exact and Natural Sciences Cartagena University Cartagena de Indias Co-lombia Morelia Institute of Technology Morelia Mexico

We show a result of symmetry for a big class of problems with condition of Neumann on the boundary in the case one dimensional. We use the method of reflection of Alexandrov and we show one application of this method and the maximum principle for elliptic operators in problems with conditions of Neumann. Some results of symmetry for elliptic problems with condition of Neumann on the boundary may be extended to elliptic operators more general than the Laplacian.

关键词： Nonlinear Boundary Value Problems Elliptic

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 atoms.While 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 constraints.To solve this fundamental limitation,we use an ultrahigh quality factor(Q)fused silica microsphere resonant cavity to form a photon pair generator.We 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 experiments.The 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 achieved.Specifically,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 demonstrated.We herald a single idler-mode photon by detecting the corresponding signal photon,filtered via transmission through a wavelength division multiplexing channel of choice.We 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 distribution.These 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