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Chinese Physics Letters 2024年第8期41卷 1-7页

作者： T.L.Belyaeva V.N.Serkin universidad autonoma del Estado de Mex.co Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita universidad autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

The main goal of our study is to reveal unex.ected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsive-core *** the base of this model,we reveal the most intriguing properties of the nonlinear tunneling of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting and stimulating analogies between the interaction of nucleus-like solitons on the repulsive barrier and nuclear sub-barrier *** main finding of this study concerns the conservation of total number of nucleons(or the baryon number)in nuclear-like soliton *** show that inelastic interactions among well-dressed repulsive-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-like solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-like solitons are similar to the nuclear form *** show that the nuclear-like reactions between well-dressed solitons are realized by“ex.hange”between“particle-like”side bands in their spectra.

关键词： solitons soliton Nonlinear

Ex.anded Porphyrin Ex.ibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCS Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry I.Nazarov Jorge Labella Alex.y V.Kuzmin Max.m A.Faraonov Evgenii N.Ivanov Salavat S.Khasanov Tomas Torres Mikhail K.Islyaikin Dmitri V.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid Institute of Solid-State Physics RAS 142432 Chernogolovka Research Institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov Institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo Institute for Advanced Research in Chemical Sciences Universidad Autonoma de Madrid28049 Madrid IMDEA-Nanociencia 28049 Madrid

The complex.tion of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this contex.,the use of ex.anded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we ex.lored the coordination of Dy^(3+)to a six.membered porphyrinoid,namely,the hemihex.phyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex.when performing the complex.tion under reductive *** this reaction,the ox.dation state of the macrocycle did not *** x.ray diffraction analysis,we found that the coordination number of Dy in this complex.was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with ex.anded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

Glutamate and ex.itotox.city in central nervous system disorders:ionotropic glutamate receptors as a target for neuroprotection

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Neuroprotection 2024年第2期2卷 137-150页

作者： Jorge Y.Magdaleno Roman Christian Chapa Gonzalez Instituto de Ingenieria y Tecnologia Universidad Autonoma de Ciudad JuarezCiudad JuarezMexico Grupo de Nanomedicina Laboratorio de Integracionde Datosy Evidenciaen Revisiones de Salud y Ciencia(LIDERSC)Universidad Autonoma de Ciudad JuarezCiudad JuarezMexico

Recent advances in neuroscience have illuminated the central role of glutamate dysregulation in various neurological *** glutamatergic system has emerged as a central player in the pathophysiology of various neurological *** dysregulation of glutamate signaling,leading to ex.itotox.city and neuronal cell death,has been a focal point in understanding the underlying mechanisms of these *** has prompted a paradigm shift in neuroprotection research,with a growing emphasis on targeting ionotropic glutamate receptors(iGluRs)to restore glutamatergic *** review provides a comprehensive overview of recent advancements in the field of iGluR-targeted *** further investigate the implications of glutamate dysregulation in the central nervous system(CNS)disorders,highlighting the complex.interplay between ex.itotox.city and *** elucidate the multifaceted factors that render neurons vulnerable to ex.itotox.c damage,emphasizing the need for innovative therapeutic *** review provides an ex.ensive survey of the burgeoning field of iGluR-targeted *** showcases the significant potential of a wide array of compounds,encompassing both natural and synthetic agents,to modulate iGluRs and ameliorate ex.itotox.city and ox.dative stress-induced neuronal *** compounds have demonstrated impressive neuroprotective effects in diverse ex.erimental models,from glutamate-induced tox.city to traumatic brain *** advocate for further research and clinical investigations to harness the full therapeutic potential of iGluR modulation,heralding a promising era in neuroprotection and CNs disorder management.

关键词： central nervous system ex.itotox.city glutamate ionotropic glutamate receptors neuroprotection

Analysis of three-dimensional vortex.s below the free surface in a continuous casting mold

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 397-406页

作者： Cesar A.Real-Ramirez Jesus I.Gonzalez-Trejo universidad autonoma metropolitana-Azcapotzalco.San Pablo 180 02200Mexico CityMexico

To study fluctuations of the free surface of liquid steel in the mold,two different models with the same casting conditions but different thicknesses were employed to analyze the hydrodynamic behavior at the top of the *** first model was a standard thickness slab,and the second had a thickness three times *** is found with the second model that above the plane formed by the steel jets,it is possible to observe four three-dimensional vortex.s that interact with the submerged entry nozzle（SEN）and mold *** using a biphasic model to simulate the interface between the liquid and air inside the mold,the flow asymmetry and the fluctuations of the free surface can be clearly observed.

关键词： continuous casting molds flow patterns three dimensional vortes mathematical models computer simulation

Effect of homogenization process on the hardness of Zn-Al-Cu alloys

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1076-1081页

作者： Jose D.Villegas-Cardenas Maribel L.Saucedo-Munoz Victor M.Lopez-Hirata Antonio De Ita-De la Torre Erika O.Avila-Davila Jorge Luis Gonzalez-Velazquez Department of Metallurgy and Materials Instituto Politecnico Nacional(IPN-ESIQIE)Mexico City 07300Mexico Department of Industrial Engineering Universidad Politecnica del Valle de MexicoMexico CityMexico Department of Materials Universidad Autonoma Metropolitana(UAM)Unidad AzcapotzalcoMexico

The effect of a homogenizing treatment on the hardness of as-cast Zn–Al–Cu alloys was investigated. Eight alloy compositions were prepared and homogenized at 350 °C for 180 h, and their Rockwell 'B' hardness was subsequently measured. All the specimens were analyzed by x.ray diffraction and metallographically prepared for observation by optical microscopy and scanning electron microscopy. The results of the present work indicated that the hardness of both alloys(as-cast and homogenized) increased with increasing Al and Cu contents; this increased hardness is likely related to the presence of the θ and τ′ phases. A regression equation was obtained to determine the hardness of the homogenized alloys as a function of their chemical composition and processing parameters, such as homogenization time and temperature, used in their preparation.

关键词： zinc–aluminum–copper alloys casting hardness homogenization phases microstructure

Escamoles Ant Eggs Liometopumapiculatumm Source of Metal Ions for Human Health

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Journal of Chemistry and Chemical Engineering 2013年第6期7卷 556-559页

作者： Virginia Melo Concepcion Calvo Tomas Quirino Susana Macin Ileana Muniz universidad autonoma metropolitana-x. Coyoacan 04960 Mexico Instituto Nacional de Ciencias Medicasy Nutricion SZ Vasco de Quiroga 14. Tlalpan 14000 Mexico

The earth crust is believed to be made of a mass of minerals and is matched by their importance in human life. The human body, depend like other leaving organisms, on several minerals as essential constituents of its ex.stence. Metal ions in foodstuff are in different chemical forms, as inorganic salts or organic molecules or complex.s with other compounds such as proteins, amino acids, enzymes and some vitamins, among others, that play an important role in human health. Entomophagy, insect consumption by several ethnic groups in Mex.co as cultural tradition since prehispanic era represent an option for population to obtain the minerals needed by the body to keep a good health. Escamoles ant eggs of the Liometopumapiculatum M genus, much appreciated either at rural communities as well as in urban cities, contain minerals with a favorable effect in human health. The aim of this study was to investigate the mineral composition of Escamoles and the benefits which can provide to the human body. Sampling was at an arid region of the Hidalgo state on April 2012. Minerals in dry basis, determined by atomic absorption spectrophotometry, with the ex.eption of phosphorus content, obtained from a triple acid digested ex.ract and determined colorimetrically. Data of mineral analysis in dry basis of Escamoles were： total minerals 5.92%; Na 0.079%; K 0.075%; Ca 0.097%; P 0.701%; Fe 0.021%; Zn 0.035% Cu 0.009%; Mg 0.998%; Mn 0.002%. Minerals quantify are not equal to total ash contained because not all of them were assess determined. Elements concentration depends not only on the total mineral composition of foodstuff the inorganic or organic form or interaction among metal ions, but also on their availability and avail of them. Minerals in Escamoles ant eggs have a considerable influence in the condition of human health.

关键词： Escamoles ant eggs metal ions human health.

Assessment of k–ε models using tetrahedral grids to describe the turbulent flow field of a PBT impeller and validation through the PIV technique

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Chinese Journal of Chemical Engineering 2018年第5期26卷 942-956页

作者： Victor x. Mendoza-Escamilla Alejandro Alonzo-Garcia Helvio R. Mollinedo Israel Gonzalez-Neria J. Antonio Yanez-Varela Sergio A. Martinez-Delgadillo Depto. Electronica Universidad Autonoma Metropolitana Azcapotzalco Av. San Pablo 180 Azcapotzalco CP 07740 Mexico D.F. Mexico CONACyT-Centro de Ingenierfa y Desarrollo Industrial Av. Piaya Pie de la Cuesta 702 Desarrollo San Pablo 76125 Queretaro Qro. Mexico UPIITA Instituto Politecnico Nacional Av. IPN 2580 G.A. Madero CP 07340 Mexico D.F. Mexico Depto. Ciencias Basicas Universidad Autonoma Metropolitana Azcapotzalco Av. San Pablo 180 Azcapotzalco CP 07740 Mexico D.F Mexico

In turbulence modeling, the RNG and Realizable models have important improvements in the turbulent production and dissipation terms in comparison to the Standard. The selection of the appropriate turbulence model has an impact on the convergence and solution in STRs, and they are used in mix.ng, multiphase modeling or as starting solution of transient models as DES and LES. Although there are several studies with the pitched blade turbine(PBT) impeller, most of them used the Standard model as representative of all k–ε models, using structured hex.hedral grids composed of low number of cells, and in some cases under ax.al symmetry ***, in this work the assessment of the Standard, RNG and Realizable models to describe the turbulent flow field of this impeller, using the Multiple Reference Frame(MRF) and Sliding Mesh(SM) approaches with tetrahedral domains in dense grids, is presented. This kind of cell elements is especially suitable to reproduce complex.geometries. Flow velocities and turbulent parameters were verified ex.erimentally by PIV and torque measurements. The three models were capable of predicting fairly the pumping number, the power number based on torque, and velocities. Although the RNG improved the predictions of the turbulent kinetic energy and dissipation rate, the Realizable model presented better performance for both approaches. All models failed in the prediction of the total dissipation rate, and a dependence of its value on the number of cells for the MRF was found.

关键词： Tetrahedral grids PIV Turbulent flow k-ε models Stirred vessel

Morphological and mineralogical characterizations of oolitic iron ore in the Ex. region, China

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 113-118页

作者： Shao-x.an Song Ernesto Fabian Campos-Toro Yi-min Zhang Alejandro Lopez-Valdivieso School of Resources and Environmental Engineering Wuhan University of Technology Instituto de Metalurgia Universidad Autonoma de San Luis Potosi

The morphological and mineralogical characterizations of a Chinese oolitic iron ore （Ex. deposit） were studied by scanning electron microscopy and energy-dispersive x.ray spectroscopy in this work. It is shown that the Ex. ore is mainly composed of hematite, quartz, apatite, and chlorite. The hematite is present as the oolitic layers and in the spaces between the aggregated ooids; quartz ex.sts as granular particles in the spaces and as nucleuses in ooids; the harmful mineral, apatite, is associated with hematite as the oolitic layers, fine dissemination, granular particles in the spaces, and nucleuses in ooids. From the viewpoint of mineral beneficiation, it is hard to separate apatite and chlorite but easy to separate quartz from hematite in the Ex. iron ore in recovering the iron values.

关键词： iron ores mineralogy morphology scanning electron microscopy

OTB-morph:One-time Biometrics via Morphing

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Machine Intelligence Research 2023年第6期20卷 855-871页

作者： Mahdi Ghafourian Julian Fierrez Ruben Vera-Rodriguez Aythami Morales Ignacio Serna Biometrics and Data Pattern Analytics Laboratory(BiDA Lab) Universidad Autonoma de MadridMadrid28049Spain

Cancelable biometrics are a group of techniques to transform the input biometric to an irreversible feature intentionally using a transformation function and usually a key in order to provide security and privacy in biometric recognition *** transformation is repeatable enabling subsequent biometric *** paper introduces a new idea to be ex.loited as a transformation function for cancelable biometrics aimed at protecting templates against iterative optimization *** proposed scheme is based on time-varying keys(random biometrics in our case)and morphing *** ex.erimental implementation of the proposed scheme is given for face *** results confirm that the proposed approach is able to withstand leakage attacks while improving the recognition performance.

关键词： Biometrics face recognition template protection morphing security

Morphological control of cadmium sulfide nanostructures by electrophoretic deposition

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Particuology 2016年第1期14卷 73-77页

作者： Alejandro Vazquez Thelma Serrano Boris Kharisov Idalia Gomez universidad autonoma de Nuevo Leon UANL Facultad de Ciencias Quimicas Av. Universidad S/N San Nicolas de los Garza Nuevo Leon 66451 Mexico

Thin films and one-dimensional CdS nanostructures were formed by electrophoretic deposition of nanoparticles with morphological control, Particles less than 1Ohm in diameter were prepared by a microwave assisted synthesis using trisodium citrate as capping agent. The particles were character- ized by UV-Vis spectrophotometry, dynamic light scattering, and x.ray diffraction. Nanoparticles in the resulting aqueous dispersion were electrodeposited without any further treatment on aluminum plates. The nanostructures consisted of thin films with surface roughness being tuned with the applied voltage. One-dimensional nanostructures were formed by varying the applied voltage and by changing the molar ratio of the precursors in the nanocrystal synthesis. These results illustrate two different mechanisms of electrophoretic deposition that lead to the formation of different nanostructures,

关键词： Electrophoretic deposition Nanostructure Nanoparticle