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化学还原法合成Cu纳米粒子（英文）

Transactions of Nonferrous Metals Society of China 2019年第7期29卷 1510-1515页

作者： M. S. AGUILAR R. ESPARZA G. ROSAS Instituto de Investigación en Metalurgia y Materiales UMSNH Morelia Michoacán 58000 Mexico centro de física aplicada y tecnología avanzada UNAM Santiago de Querétaro 76230 Mexico

通过室温化学还原合成Cu纳米粒子(CuNPs)。采用硼氢化钠还原Cu^2+离子,并用聚乙烯吡咯烷酮进行稳定化处理。考察还原剂/前驱体盐(RA/PS)比值的变化对CuNPs粒径和形貌的影响。利用紫外-可见光谱(UV-Vis)、X射线衍射(XRD)、扫描电镜(SEM)... 详细信息

通过室温化学还原合成Cu纳米粒子(CuNPs)。采用硼氢化钠还原Cu^2+离子,并用聚乙烯吡咯烷酮进行稳定化处理。考察还原剂/前驱体盐(RA/PS)比值的变化对CuNPs粒径和形貌的影响。利用紫外-可见光谱(UV-Vis)、X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)对合成的材料进行表征。UV-Vis光谱显示,569nm处存在一CuNPs的等离激元峰;另一峰位于485nm处,为Cu2O的特征峰。XRD分析表明,合成的材料为fcc-Cu相,并含有少量的fcc-Cu2O化合物。SEM和TEM研究显示,当RA/PS比值为2.6时,得到粒径约7nm的半球形CuNPs微粒。过量的聚乙烯吡咯烷酮稳定剂对于防止CuNPs的氧化至关重要。另一方面,当RA/PS比在2.0~1.84范围内时,获得较大粒径的多面体形Cu2O颗粒,最大粒径可达150nm。此外,在RA/PS比为1.66时,得到在其尖端具有量子限域效应的星形Cu2O粒子。

关键词：铜纳米粒子 NaBH4 化学还原聚乙烯吡咯烷酮稳定化星形Cu2O

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Effect of Baf2 addition on luminescence properties of Er3+/yb3+ co-doped phosphate glasses

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Journal of Rare Earths 2018年第1期36卷 58-63页

作者： K.Linganna R.Narro-García P.Manasa H.desirena E.de la Rosa C.K.Jayasankar department of Physics Sri Venkateswara University centro de Investigaciones en Optica Advanced Optical Lens Research Center Korea Photonics Technology Institute (KOPTI) Centro de Física Aplicada y Tecnología Avanzada UNAM

Er/ybco-doped phosphate glasses(PO-AlO-BaO-Baf-KO-ErO-ybO) with varying Bafcontent,were prepared by a conventional melt quenching technique and their spectroscopic properties were examined through the Raman, absorption, emission and decay measurements. Raman spectra(350-1400 cm) of the Er/ybco-doped phosphate glasses with varying Bafcontent, were recorded upon laser excitation at 785 nm. Near infrared luminescence spectra were measured in the1400-1600 nm region under 970 nm diode laser excitation and characteristic band was observed at1533 nm corresponding to ~4Ⅰ→~4Ⅰtransition of Erion. The decay curves for the ~4Ⅰlevel of Erion, were measured and the lifetime is found to decrease from 7.94 to 7.70 ms when Bafcontent increases from 0 to 8 mol% and then increases up to 7.83 ms with further increase in Bafcontent(12 mol%). The emission cross-section.lifetime and figure of merit for the ~4Ⅰ→~4Ⅰtransition of Erion were evaluated and compared to the other host matrices. The upconversion luminescence was measured and intense red emission was observed for all the studied samples.

关键词： Er3+/yb3+co-doped phosphate glasses Raman spectra Absorption and emission cross-sections Lifetime Rare earths

Nano to micro size transition of hydroxyapatite in porcine bone during heat treatment with low heating rates

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Progress in Natural Science:Materials International 2020年第4期30卷 494-501页

作者： Angélica M.Castillo-Paz Sandra M.Londo?o-Restrepo Liliana Tirado-Mejía M.A.Mondragón Mario E.Rodríguez-García Grupo de Optoelectrónica Instituto Interdisciplinario de las Ciencias Universidad del Quindío centro de Investigación y de Estudios Avanzados del IPN departamento de Nanotecnología Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla

This work focuses on the changes of raw hydroxyapatite obtained from porcine bones during heat treatment with heating rates of 2.5 and 5.0 °C/min between 600 °C and 1100 °C. High-Resolution transmission electron microscopy(HR-TEM) images showed that raw hydroxyapatite was formed by high-ordered nanometric platelet crystals with a length of around 18 nm and width around 7 nm. High-Resolution scanning electron microscopy(HR-SEM) images evidenced the coalescence phenomena during heating giving. It was found that the growth of the crystals and the transition from nano to a micro-size occurred at around 700 °C. And the changes in the full width at half maximum(fWHM) for the characteristic(002) plane of the X-ray diffraction patterns and the fWHM of the characteristic Raman band at 960 cm-1 for ν1 PO43-exhibited the transition from nano to a micro size, that was confirmed by HR-SEM images and the thermogravimetric(TG) analysis. The porosity of the BIOHAp changes from intra nanometric to intercrystalline.

关键词： Bone composition Hydroxyapatite nanoparticles Mineral composition Porosity formation Raman analysis

Non-Linear Effects in Optical Systems by Lie Algebra and Symplectic Mapping

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Journal of Modern Physics 2022年第11期13卷 1314-1323页

作者： Víctor M. Casta&ntilde o centro de física aplicada y tecnología avanzada/Secretaría de desarrollo Institucional Universidad Nacional Autónoma de México Queretaro México

The use of signals of different frequencies determines the geometrical deviation with respect to the optical axes of a given beam. This angle can be determined by Sympletic Map (SM), a powerful and simple mathematical tool for the characterization and construction of images in Geometrical Optics. The Sympletic Map constitutes a Lie Group, with an algebra associated: the Lie Algebra. In general, the SM can be expressed as an infinite series, where each term corresponds to different contributions produced by the optical devices that constitute the optical system (lenses, apertures, bandwidth cutoff, etc.). The level of correction to be performed on the image to recover the original object is clear and controllable by SM. This formalism can be extended easily to physical optics to describe diffraction and interference phenomena.

关键词： Symplectic Mapping Geometrical Optics Non-Linear Effects

Synthesis and Thermal Behavior of Metallic Cobalt Micro and Nanostructures

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Nano-Micro Letters 2011年第1期3卷 12-19页

作者： Marlene González Montiel P.Santiago-Jacinto J.A.I.Díaz Góngora E.Reguera Geonel Rodríguez-Gattorno centro de Investigación en Ciencia aplicada y tecnología avanzada Instituto de física Circuito de la Investigación Científica Ciudad Universitaria departamento de física aplicada CINVESTAV-IPN

In this contribution, a comparative study of metallic cobalt micro and nanoparticles obtained in solution by four different chemical routes is reported. Classic routes such as borohydride reduction in aqueous media and the so-called polyol methodology were used to obtain the cobalt nanostructures to be studied. Using CTAB as surfactant, cobalt hollow nanostructures were obtained. The use of strong reducing agents, like sodium borohydride, favors the formation of quasi-monodispersed nanoparticles of about 2 nm size but accompanied with impurities; for hydrazine(a mild reducer), nanoparticles of larger size are obtained which organize in spherical microagglomerates. Valuable information on the particles thermal stability and on nature of the species anchored at their surface was obtained from thermogravimetric curves. The samples to be studied were characterized from UV-vis, IR, X-ray diffraction, and electron microscopy images(scanning and transmission).

关键词： Metallic Cobalt Cobalt nanoparticles Magnetic nanoparticles Hollow magnetic microparticles

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Agro-Industrial Waste as a Source of Raw Material:Eggshell and Ash of Agave salmiana Useful for the Synthesis of Hydroxyapatite

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Journal of Renewable Materials 2022年第12期10卷 3559-3572页

作者： Nora Elizondo-Villarreal Luz HVerástegui-Dominguez Jose JQuijano-Briones francisco JVázquez-Rodríguez Eden Rodríguez-Castellanos Enrique López-Cuellar Ernesto Torres-Lopez Victor MCastaño-Meneses Universidad Autónoma de Nuevo León Facultad de Ciencias Fisico MatemáticasCiudad UniversitariaSan Nicolás de los GarzaNuevo LeónMéxico Universidad Autónoma de Nuevo León Facultad de ArquitecturaCiudad UniversiariaSan Nicolás de los GarzaNuevo LeónMéxico Universidad Autónoma de Nuevo León Facultad de Ingeniería Mecainicay EléctricaCiudad UniversitariaSan Nicolás de los GarzaNuevo LeónMéxico centro de física aplicada y tecnología avanzada Universidad Nacional Autonoma de MéxicoQuerétaroMéxico

Agave salmiana ash and poultry eggshell powder as CaO sources were used for obtaining nanostructured hydro-xyapatite(HAP).The synthesis was carried out by the Green Chemistry Hydrothermal Biosynthesis at 180℃ with a pH of 5,by reacting CaO from Agave Salmiana ash and Eggshell powder,with dibasic caldium phosphate(CaH-PO_(4)+2H_(2)O)in an aqueous solution,with Aloe barbadensis extract.The product was characterized by X-ray dif-fraction,fourier transform infrared spectroscopy(fT-IR),Scanning Electron Microscopy(SEM),and Transmission Electron Microscopy(TEM).The size and shape of the hydroxyapatite particles changed dramati-cally in the presence of Aloe barbadensis.Large crystals of Hydroxyapatite were observed when Eggshell powder and Agave salmiana ash were used as raw materials in the presence of the Aloe barbadensis surfactant.Crystals with shapes of ribbons and plates from 1 micrometers to 8 micrometers were observed when using the eggshell powder in the presence of Aloe bar badensis and,in the case of Agave salmiana ash in the presence of Aloe bar-badensis,crystals with shapes of quadra ngular prisms and hexagonal(polyhedra)with sizes from 2 micrometers to 20 micrometers were observed.Hydroxyapatite was therefore successfully biosynthesized by a green and sus-tainable method that reduces the environmental impact.

关键词： Hydroxyapatite raw materials Agave salmiana eggshell Aloe barbadensis surfactant

Carbon dioxide fixation into cyclic carbonates at room temperature catalyzed by heteroscorpionate aluminum complexes

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Green Chemical Engineering 2022年第3期3卷 280-287页

作者： felipe de la Cruz-Martinez Jose A.Castro-Osma Agustin Lara-Sanchez Universidad de Castilla-La Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de Ciencias y Tecnologias QuimicasCiudad Real13071Spain Instituto de Investigaciones Quimicas(IIQ) Departamento de Quimica Inorganica and Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Consejo Superior de Investigaciones Cientificas(CSIC)and University of SevillaSevilla41092Spain Universidad de Castilla-La Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de FarmaciaAlbacete02071Spain

Novel mono-and bimetallic scorpionate aluminum compounds have been designed and characterized by spec-troscopic methods.These organometallics complexes,in combination with tetrabutylammonium bromide as cocatalyst,displayed good catalytic activity for the cycloaddition of styrene oxide and CO_(2) under ambient con-ditions.Among the compounds tested,monometallic complex 3 featuring diethylamino groups showed the highest catalytic activity.This catalytic system catalyzed the formation of cyclic carbonate products from their corresponding epoxides at room temperature and 1 bar of CO_(2) pressure in the absence of a solvent in good yields and excellent selectivities.

关键词： CO_(2) Epoxides Cyclic carbonates Aluminum complexes

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Nonlinear Coefficient determination of Au/Pd Bimetallic Nanoparticles Using Z-Scan

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Advances in Nanoparticles 2013年第3期2卷 223-228页

作者： José Luis Jiménez Pérez Rubén Gutiérrez-fuentes José francisco Sánchez Ramírez Omar Uriel García Vidal Daniel Erick Téllez-Sánchez Zormy Nacary Correa Pacheco Alfredo Cruz Orea Jesús Antonio fuentes García centro de Investigación en Ciencia aplicada y tecnología avanzada México D.F. México departamento de física Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional México D.F. México Unidad Profesional Interdisciplinaria en Ingeniería y tecnologías avanzadas del IPN México D.F. México

In this paper we present the nonlinear optical characterization of Au/Pd nanoparticles in order to obtain the nonlinear refractive indices using the Z-scan technique. The experiments were performed using a 514 nm laser beam Ar+, with 14 Hz of modulation frequency, as excitation source. By using a lens the excitation beam was focused to a small spot and the sample was moved across the focal region along the z-axis by a motorized translation stage. Seven samples with different concentration ratio of Au/Pd nanoparticles were prepared by simultaneous reduction of gold and palladium ions in presence of poly (N-vinyl-2-pirrolidone) (PVP) using ethanol as a reducing agent. In this work, we report the application of the Z-scan technique, to generate optical transmission of laser light as a function of the z position for solutions containing bimetallic nanoparticles of Au (core)/Pd (shell) with average sizes ranging from 3 to 5 nm. The magnitude of the obtained nonlinear refractive index was in the order of 10?8 cm2/W. Our results show that the nonlinear refractive index has a nonlinear behavior when the (Au/Pd) ratio was increased.

关键词： Nanofluids Nanoparticles Nonlinear Refractive Indices Z-Scan

Phase Transition in Superconducting Thin films of Tl System Employing a One-Zone furnace and deposited by Spray Pyrolysis

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Materials Sciences and Applications 2013年第11期4卷 739-745页

作者： Jorge Luis Rosas-Mendoza L. Perez-Arrieta Miguel Aguilar-frutis Ciro falcony R. Vázquez-Arreguín Alejandro Miguel Rosas-Mendoza centro de Investigación en Ciencia aplicada y tecnología avanzada Instituto Politécnico Nacional México D.F. México centro de Investigación en Ciencia aplicada y tecnología avanzada Instituto Politécnico Nacional México D.F. México Unidad Profesional Interdisciplinaria de Biotecnología Instituto Politécnico Nacional México D.F. México departamento de física Centro de Investigación de Estudios Avanzados (CINVESTAV-IPN) México D.F. México Unidad Académica de física Universidad Autónoma de Zacatecas (UAZ) Zacatecas México

A study of the phase transitions in superconducting thin films of the Thallium-Barium-Calcium-Copper (TBCCO) system is carried out. In particular, it was got the Tl-1223 phase. for this purpose, and using the ultrasonic spray pyrolysis technique, Barium-Calcium-Copper precursor films were first obtained. Upon deposition of the precursor films, and as a second step, they were thallium (Tl) diffused in the one-zone furnace at 860°C. This methodology resulted in superconducting films that showed a phase transition as follows: Tl-2223 → Tl-2223 + Tl-2212 → Tl-2212 → Tl-1223, achieved between 2 and 7 hours of thallium diffusion. The evidence of the phase transitions was corroborated by the experimental results of X-ray diffraction, energy dispersive spectroscopy and resistance-temperature measurements.

关键词： Superconductors Thin films Ultrasonic Spray Pyrolysis