检索结果-南通市图书馆

Effect of the initial ECAP passes on crystal texture and residual stresses of 5083 aluminum alloy

International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 801-808页

作者： L.Romero-Reséndiz a.flores-rivera I.A.Figueroa C.Braham C.Reyes-Ruiz I.Alfonso G.González Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.de México 04510México Procédés et Ingénierie en Mécanique et Matériaux Arts et MétiersParis 75013France Departamento de Diseño y Manufactura Facultad de IngenieríaUniversidad Nacional Autónoma de MéxicoPIIT Apodaca 66629México Instituto de Investigaciones en Materiales Unidad MoreliaUniversidad Nacional Autónoma de MéxicoMorelia 58190México

To produce a highly refined microstructure,several metals or alloys have been processed via equal-channel angular pressing(ECAP).In this work,the mechanical and microstructural changes of the 5083 aluminum alloy in H11 condition after processed by two ECAP passes were *** ECAP H13 steel die with an inner angle(α)of 120°and outer curvature(β)of 20°was *** microstructural changes were associated with the loss of texture *** morphologies of the Mg2Si andα-Al(Mn,Fe)Si precipitates for the sample at the initial condition were similar to those subjected to two ECAP *** peak broadening measured by X-ray diffraction revealed an increment of both grain refinement and *** the second extrusion pass,the hardness increased by 62%compared with the initial ***,the heterogeneous hardness behavior was compatible with a highly localized dislocation *** two ECAP passes,shear parallel bands were observed to be at nearly 45°to the extrusion *** evaluation of first-order residual stress as a function of the depth of the analyzed sample displayed compressive or tensile values,depending on the measured *** the plastic deformation applied,the first and second-order residual stresses exhibited significant ***-Hall plots showed positive slopes,indicating an increment in the microstrain.

关键词： aluminum alloy equal-channel angular pressing texture microstructure residual stress

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Facilitation by nurse plants contributes to vegetation recovery in human-disturbed desert ecosystems

引用

Journal of Plant Ecology 2016年第5期9卷 485-497页

作者： Ernesto I.Badano Omar R.Samour-Nieva Joel flores JoséL.flores-flores Jorge a.flores-Cano Juan P.Rodas-Ortíz División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José2055Colonia Lomas 4ta SecciónC.P.78216San Luis PotosíMéxico Instituto de Investigación de Zonas Desérticas Universidad Autónoma de San Luis PotosíAltair 200Fraccionamiento del LlanoC.P.78377San Luis PotosíMéxico Facultad de Agronomía Universidad Autónoma de San Luis PotosíKm.14.5 Carretera San Luis-MatehualaApdo.Postal 32Soledad de Graciano SánchezC.P.78321San Luis PotosíMéxico

Aims Facilitation by nurse plants is a common interaction in harsh environments and this positive plant-plant interaction may promote vegetation recovery in ecosystems affected by human *** the relevance of this process,however,requires assessing how nurse plants influence the establishment of other species,as well as the proportion of species in the regional species pool that would benefit from the presence of nurse plants in human-disturbed ***,since vegetation recovery is a time-dependent process,the community-level consequences of facilitation are likely to vary among landscapes with different disturbance ***,an integrative perspective of the relevance of nurse plants for vegetation recovery could be obtained by measuring their effects across different human-disturbed landscapes of the target *** study focuses on these issues and uses a regional-scale approach to assess the community-level effects of a widespread nurse plant of American deserts,the creosotebush(Larrea tridentata).Methods This study was conducted in the southernmost portion of Chihuahuan Desert because most floodplain valleys of this region have been affected by human activities during the past *** this study,we selected 10 floodplain valleys differing in their age(*** time elapsed after human activities were ceased).At each landscape,we measured the cover of creosotebushes and the proportion of plant species positively associated with them,as well as the density of seeds in the soil beneath creosotebush *** these data were regressed against the age of the ***,to assess whether positive association patterns were due to facilitation or other processes,we conducted field experiments and measured the ecophysiological performance of plant species established beneath and outside creosotebush *** Findings Most plant species from the target region were positively associated to creosotebushes,and our field

关键词： Chihuahuan desert community-level effects community succession positive interactions Mexico

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Dendritic spine degeneration:a primary mechanism in the aging process

引用

Neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo flores Leonardo Aguilar-Hernández Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de Ciencias Forenses(INCIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto Nacional de Medicina Genómica(INMEGEN) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023).

关键词： aging process stress

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cerium extraction by metallothermic reduction using cerium oxide powder injection

引用

Journal of Rare Earths 2011年第1期29卷 74-76页

作者： J.S.Luna A a.flores V R.Muiz V A.F.Fuentes J.Torres N.Rodríguez R J.C.Ortiz P.Orozco CINVESTAV Unidad Saltillo Saltillo-Monterrey Highway Km.13.5P.O.Box 66325000SaltilloCoahuilaMéxico Faculty of Engineering Autonomous Univer-sity of CoahuilaCamporedondo UnitSaltilloCoahuilaMéxico Department of Metal Mechanics Technological Institute of SaltilloV.Carranza Blvd 2400SaltilloCoahuilaZC 25280México Academic Unit of Engineering Autonomous University of CoahuilaLopez Velarde Av.ZacatecasZac.ZC 98060

This work presented the feasibility of cerium recovery by Al-Mg alloy through the metallothermic reduction of CeO2 to obtain a master alloy Al-4%Ce. The master alloy obtained in this investigation was for the grain refinement and modification of Al-Si alloys. The reagent was incorporated into a molten alloy using the submerged powder injection technique, and metallic samples were obtained during injection. Chemical and microstructural analyses （by inductively coupled plasma （ICP） and scanning electron microscopy （SEM）, respectively） confirmed the possibility of Ce uptake in the bath （0 to 4 wt.%）, as CeO2 was reduced through metallothermic reactions in the molten alloys. Based on the characterization of reaction products, the sequence of the reaction was proposed.

关键词： cerium recovery metallothermic reduction reaction products rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Differential response of injured and healthy retinas to syngeneic and allogeneic transplantation of a clonal cell line of immortalized olfactory ensheathing glia:a double-edged sword

引用

Neural Regeneration Research 2025年第8期20卷 2395-2407页

作者： María Norte-Muñoz María Portela-Lomba Paloma Sobrado-Calvo Diana Simón Johnny Di Pierdomenico Alejandro Gallego-Ortega Mar Pérez JoséMCabrera-Maqueda Javier Sierra Manuel Vidal-Sanz María Teresa Moreno-flores Marta Agudo-Barriuso Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la SaludMurciaSpain Experimental Sciences Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain Anatomy Histology and Neuroscience DepartmentMedicine FacultyUniversidad Autónoma de MadridMadridSpain Center of Neuroimmunology Service of NeurologyLaboratory of Advanced Imaging in Neuroimmunological DiseasesHospital Clínic of BarcelonaInstitut d’Investigacions Biomèdiques August Pi i Sunyer(IDIBAPS)and Universitat de BarcelonaBarcelonaSpain Medicine Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain

Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic ***,it is unknown whether olfactory ensheathing glia also have neuroprotective *** ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion ***,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve *** ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive *** and gene expression analyses were *** bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡ*** and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an *** axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 *** these retinas,microglial anatomical activation was higher than after optic nerve crush *** intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or ***,neuroprotection of axotomized retinal ganglion cells did not improve with these *** different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables.

关键词： cell therapy immune recognition major histocompatibility complex class II(MHCII) neuroprotection olfactory ensheathing glia retinal ganglion cells

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ligand effects on the structure and vibrational properties of the thiolated Au18 cluster

引用

Progress in Natural Science:Materials International 2016年第5期26卷 510-515页

作者： Alfredo Tlahuice-flores CICFIM-Facultad de Ciencias Físico-Matemáticas Universidad Autónoma de Nuevo León

Most of the studies devoted to thiolated gold clusters suppose that their core and Au-S framework do not suffer from distortion independently of the protecting ligands（-SR） and it is assumed as correct to simplify the ligand as SCH3. In this work is delivered a systematic study of the structure and vibrational properties（IR and Raman）of the Au18（SR）14cluster. The pursued goal is to understand the dependency of the displayed vibrational properties of the thiolated Au18cluster with the ligands type. A set of six ligands was considered during calculations of the vibrational properties based on density functional theory（DFT） and in its dispersioncorrected approach（DFT-D）.

关键词： Gold cluster Ligand effects Structure Vibration Au18(SR)14 Density functional theory

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Leaching kinetics in cyanide media of Ag contained in the industrial mining-metallurgical wastes in the state of Hidalgo, Mexico

引用

International Journal of Mining Science and Technology 2014年第5期24卷 689-694页

作者： Juan Hernandez Francisco Patino Isauro rivera Iván Alejandro Reyes Misrael Uriel flores Julio Cesar Juarez Martín Reyes Research Centre in Materials and Metallurgy Autonomous University of Hidalgo Pachuca 42184 Mexico

The leaching kinetics in cyanide media of the silver contained in the Dos Carlos waste tailings at the City of Pachuca de Soto, Hidalgo State, Mexico were carried out. The used material contained the following chemical composition: 56 10-6of Ag, 0.6 10 6of Au and 70.43%(by weight) of SiO2; 7.032%(by weight) of Al2O3; 2.69%(by weight) of Fe; 0.46%(by weight) of Mn; 3.98%(by weight) of K2O; 3.34%(by weight) of CaO; 2.50%(by weight) of Na2O; 0.04%(by weight) of Zn; 0.026%(by weight) of Pb. The mineralogical phases present were the following: Silica, albite, argentite, berlinite, orthoclase, potassium jarosite, and natrojarosite. In the leaching kinetics in cyanide media, and under the studied conditions,the effect of the CN concentration on the reaction rate has no effect on the whole process of alkaline cyanidation, of which the reaction order is n 0. Temperature has an effect on the cyanidation rate of the reaction, with an activation energy of 47.9 KJ/mol. At the same time, when the particle size decreases there is an increase in the reaction rate, which is inversely proportional to the particle diameter; when increasing the NaOH concentration there is an increase in the reaction rate Kexp, with a reaction order(n) of 0.215 under the studied ranges.

关键词： Silver Waste tailings Cyanidation Leaching

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Curcuma longa L. extract improves the cortical neural connectivity during the aging process

引用

Neural Regeneration Research 2017年第6期12卷 875-880页

作者： Gonzalo flores Laboratorio de Neuropsiquiatría Instituto de Fisiología Benemérita Universidad Autónoma de Puebla

Turmeric or Curcuma is a natural product that has anti-inflammatory, antioxidant and anti-apoptotic pharmacological properties. It can be used in the control of the aging process that involves oxidative stress, inflammation, and apoptosis. Aging is a physiological process that affects higher cortical and cognitive functions with a reduction in learning and memory, limited judgment and deficits in emotional control and social behavior. Moreover, aging is a major risk factor for the appearance of several disorders such as cerebrovascular disease, diabetes mellitus, and hypertension. At the brain level, the aging process alters the synaptic intercommunication by a reduction in the dendritic arbor as well as the number of the dendritic spine in the pyramidal neurons of the prefrontal cortex, hippocampus and basolateral amygdala, consequently reducing the size of these regions. The present review discusses the synaptic changes caused by the aging process and the neuroprotective role the Curcuma has through its anti-inflammatory, antioxidant and anti-apoptotic actions.

关键词： Curcuma longa cortical curcumin hippocampus synaptic antioxidant spine connectivity cortex

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Implementation of Neural Networks in Time Series to Generate a Portfolio of Investment in Cryptocurrencies

引用

Journal of Mathematics and System Science 2020年第1期10卷 1-12页

作者： Jose B.Hernandez C. Jorge a.flores S. Jesus Lares Escuela de Matematicas Universidad Central de VenezuelaLos Chaguaramos1020CaracasVenezuela Centro de Investigacion en Matematicas A.C.Unidad Monterrey.Av.Alianza Centro 502PIIT 66628ApodacaNuevo LeonMexico EY Wavespace MadridSpain Parallel and Distributed Computing Center Universidad Central de VenezuelaLos Chaguaramos1020CaracasVenezuela

The present work aims to implement two types of neural networks and an analysis of a multivariate time series model of VAR type to predict the price of cryptocurrencies like Bitcoin,Dash,Ethereum,Litecoin,and *** subject has been popular in recent years due to the rapid price fluctuations and the immense amount of money involved in the cryptocurrencies *** technologies have been developed around cryptocurrencies,with Blockchain rising as the most *** has been implementing other information technology projects which have helped to open a wide variety of job positions in some industries.A“New Economy”is emerging and it is important to study its basis in order to establish the pillars that help us to understand its behavior and be ready for a new era.

关键词： Neural networks time series cryptocurrencies VAR models

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A transition from a large open pit into a novel “macroblock variant” block caving geometry at Chuquicamata mine, Codelco Chile

引用

Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 549-561页

作者： German flores Alex Catalan Newcrest Mining Ltd. Melbourne3004Australia Codelco Chile Santiago8320000Chile

With a history of more than 100 years, Chuquicamata has become one of the largest open pits in the world. Its current depth of 1100 m, length of 4500 m and width of 3000 m, resulting in haulage distances of over 11,000 m from pit bottom to the processing plant or waste dumps, with waste/ore ratio greater than 4 and much lower grades, are effectively determining its profitable limit by the end of this decade. Currently, there are over 4300 Mt of geological resources containing 0.7% of copper and 340 ppm (1 ppm = 1 g/t) of molybdenum below the final pit shell. The corresponding orebody geometry is 3000 m northsouth, 300-800 m eastwest and the drilling campaign suggested the existence of more than 900 m of mineable ore from the final pit bottom. This is in spite of the fact that the Chuquicamata orebody is still open at depth. The business case to continue with the mining of the Chuquicamata orebody is to change from the current large open pit to a novel macroblock variant block caving geometry. This requires a production rate of 140,000 t/d (50 Mt per annum), with a continuous material handling system to achieve the 7-year ramp-up to full production. The resolution of a number of known technical, operational and logistical challenges outside current industry practises which Chuquicamata will face over its projected 40-year mine life is therefore essential. These challenges include simultaneous operations of open pit and underground macroblocks and from the initial lift to the second lift, rapid ramp-up and optimum sequencing of the planned macroblocks, early dilution from the west fault and late dilution from potential slope failures, and the potential for major operational hazards. An equally important issue to be addressed is cultural given that the mining history in the northern region of Chile, which includes Chuquicamata, is predominantly open pit. This paper presents a synopsis of the main challenges that the Chuquicamata underground project will face in order t

关键词： Macroblock variant Block caving Cave propagation Early and late dilutions Intensive preconditioning Rib pillar West fault Ore buffer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：