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Lanthanum-exchanged zeolite and clay as anticorrosive pigments for galvanized steel

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Journal of Rare Earths 2014年第4期32卷 352-359页

作者： S.Roselli n.Bellotti C.deyá M.Revuelta B.del Amo R.Romagnoli CIdePInT(Centro de investigación y desarrollo en tecnología de Pinturas)(COnICET-CIC)

A wide variety of inhibitive pigments is now being offered as possible alternatives to chromate and lead compounds for painted metals protection. Unfortunately, the most wide spread of these substitute pigments, zinc phosphate, has, at present, raised some environmental concern because phosphate causes the eutrophication of water courses and zinc itself is toxic. The aim of this re-search was to study the anticorrosive performance of a mixture consisting of zinc phosphate, modified zeolite and clay （bentonite） in order to diminish phosphate content in paints. The zeolite and the clay were exchanged with La（III） ions, as inorganic green inhibitor. In the first step, the anticorrosion protection by La（III） ions in solution was assessed by electrochemical tests. In the second step, an epoxy-polyamide paint formulated with the pigment mixture applied on galvanized panels was studied by salt spray test and electro-chemical noise measurements （enM）. The results showed that it was possible to replace part of the zinc phosphate content in the paint with the exchanged zeolite and the clay.

关键词： exchanged pigments corrosion anticorrosive paints electrochemical noise measurements rare earths

Reassessing the AMPK-MTORC1 balance in autophagy in the central nervous system

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neural Regeneration Research 2025年第11期20卷 3209-3210页

作者： Marta García-Juan Mario Villa Irene Benito-Cuesta Lara Ordónez-Gutiérrez Francisco Wandosell Centro de Biología Molecular“Severo Ochoa”(CSIC-UAM) Nicolas Cabrera 1Universidad Autónoma de MadridMadridSpain Fisiología Animal Departamento de BiologíaFacultad de CienciasUniversidad Autónoma de MadridMadridSpain department of Clinical neuroscience CMM Karolinska Universitetssjukhuset SolnaStockholmSweden departamento de Bioquímica y Biología Molecular Universidad Complutense de MadridMadridSpain Centro de investigación Biomédica en Red de enfermedades neurodegenerativas(CIBERnED) MadridSpain

Autophagy is a cellular degradation and recycling system,indispensable for cellular and organ development,homeostasis,and *** cellular process is evolutionarily highly conserved to quality control of many proteins and dysfunctional organelles,which finally recycle components as amino *** process is effective during normal physiology as part of anabolism and plays an additional important role during starvation(Dikic and Elazar,2018).Different types of autophagy have been chara cterized based on their dynamic,mechanism of action,target substrates,and protein *** of them are macroautophagy(hereafter called"autophagy"),microa utophagy,and chape rone-media ted autophagy(Fleming et al.,2022).

关键词： homeostasis system hereafter

Plant Oil-Based Waterborne Polyurethanes: A Brief Review

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Journal of Renewable Materials 2020年第6期8卷 579-601页

作者： VerónicaL.Mucci M.E.Victoria Hormaiztegui Mirta I.Aranguren instituto de investigaciones en ciencia y tecnología de Materiales(InTEMA) Universidad Nacional de Mar del Plata(UNMdP)-Consejo Nacional de Investigaciones en Ciencia y Tecnología(CONICET)Facultad de IngenieríaMar del PlataCP 7600Argentina Centro de investigación y desarrollo en ciencia y tecnología de Materiales(CITEMA) Universidad Tecnológica Nacional(UTN)Comisión de Investigaciones Científicas de la Provincia de Buenos Aires(CIC)Facultad Regional La PlataBerissoCP 1923Argentina

The increasing pressure from consumers and policy makers to reduce the use of synthetic polymers,whose production contributes to the depletion of non-renewable resources and are usually non-biodegradable,has prompted the efforts to find suitable bio-based sources for the production of *** oils have been a frequently spotted in this search because they are versatile,highly available and a low cost liquid biosource,which can be used in the synthesis of a wide plethora of different polymers and reactive *** the same idea of reducing the environmental stress,the traditional polyurethanes that are soluble in organic solvents have been targeted for replacement,particularly in applications such as adhesives and coatings,in which the solvent is released to the atmosphere increasing the air ***,waterborne polyurethanes(WBPU),which are polyurethane dispersions(PUD)prepared in aqueous media,release benign water to the atmosphere during use as supported or self-standing films for different *** this brief review,the contributions to the development of WBPUs based on vegetable oils are discussed,focusing mainly on the contributions of the last *** synthesis of ionic and nonionic PUDs,their characterization and the properties of the resulting dried materials,as well as derived composite materials are considered.

关键词： Vegetable oils polyurethane dispersions(PUD) waterborne polyurethane(WBPU) biopolyols biopolyurethanes coatings adhesives ink binders

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

Hydrodeoxygenation of vegetable oil in batch reactor:Experimental considerations

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Chinese Journal of Chemical engineering 2020年第6期28卷 1670-1683页

作者： Alexis K.noriega Alexis Tirado Cecilia Méndez Gustavo Marroquín Jorge Ancheyta instituto Politécnico nacional Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Unidad LegariaLegaria 694Col.Irrigación 11500Mexico instituto Mexicano del Petróleo Eje Central Lázaro Cárdenas Norte 152San Bartolo Atepehuacan 07730Mexico

The generation of reliable experimental data in any experimental scale requires proper procedures not only for the reaction step but also for the feed preparation,separation,and characterization of products as well as calculations of conversion and product *** reactor is the most used experimental setup for carrying out exploratory studies for catalyst screening and *** work is focused on describing and discussing a step-by-step methodology for conducting experiments for catalytic hydrotreating of vegetable oils in batch *** proposed methodology considers literature and own experiences on advantages and disadvantages of different feed types,catalysts,experimental setup and procedures,effect of reaction parameters,separation and characterization of products,and calculations.

关键词： Vegetable oils Hydrotreating Batch reactor

A novel and stretchable carbon-nanotube/ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael Perez-Gonzalez Christian Gomez-Solis Luis Armando Diaz-Torres Armando encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo nacional de ciencia y tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y nanoestructurados(GEMAnA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CnTs),silicon rubber and ni@TiO_(2):W nanoparticles(TiWni nPs) with average size of 37±2 *** images showed that the TiWni nPs decorated the surface of the CnT fibers,which are oriented in a preferential *** nPs presented a mixture of anatase/rutile phases with cubic *** performance of the TiWni powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible *** results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CnT composite (stretched at 0%),TiWni powders,CnT+TiWni(stretched at 0%),CnT+TiWni (stretched at 50%) and CnT+TiWni (stretched at 100%),***,stretching the CnT+TiWni composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF ***/absorbance measurements confirmed the presence of such ***,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their *** results of this investigation confirmed that the stretchable CnT/TiWni-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

Historical fluxes of metal and metalloids in an aquatic ecosystem affected by land-use change and mining activities in northwestern Mexico

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International Journal of Sediment Research 2023年第5期38卷 724-738页

作者： Ochoa-Contreras Roberto Jara-Marini Martín enrique Ruiz-Fernández Ana Carolina Sanchez-Cabeza Joan Albert Meza-Figueroa Diana Pérez-Bernal Libia Hascibe Posgrado en ciencias Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo 2. Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo Unidad Acad emica Mazatlán Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de M exico departamento de Geología División de Ciencias Exactas y Naturales Universidad de Sonora Rosales y Encinas

Freshwater reservoirs are essential owing because of their ecological, economic, and social *** are particularly vulnerable to contamination, as of metal and metalloids, derived from anthropogenic activities like mining. The temporal variations in trace element concentrations(arsenic(As),mercury(Hg), chromium(Cr), copper(Cu), nickel(ni), lead(Pb), and zinc(Zn)), enrichment, fluxes, and possible sources were evaluated by studying two sediment cores from the La Angostura(AnG) Reservoir(northwest Mexico), using210Pb geochronology. The enrichment factors showed from null to minor enrichment for most elements, but moderate to severe enrichment of mercury(Hg). Most trace element concentrations had a detrital origin, and notable Hg concentration increases since the past decade were associated with severe drought periods, likely resulting from wildfires. The observed sediment concentrations of As and Hg can cause adverse effects on biota in the ecosystem since they are above the probable effect level(PEL). development of strategies for metal attenuation in this reservoir is recommended and metals should be controlled until specific ecotoxicological studies are performed.

关键词： Aquatic ecosystems ~(210)Pb geochronology Mining activities Metals Metalloids enrichment factors

Effects of Silicon nanoparticles on the Transient Liquid Phase Bonding of 304 Stainless Steel

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Journal of Materials Science & Technology 2014年第3期30卷 259-262页

作者： H.M.Hdz-García A.I.Martinez R.Mu?oz-Arroyo J.L.Acevedo-Dávila F.García-Vázquez F.A.Reyes-Valdes Corporación Mexicana de investigación en Materiales S.A.de C.V. Ciencia y Tecnología No.790 Fracc.Saltillo 400 Saltillo Coah.CP.25290 Mexico Centro de investigación y de Estudios Avanzados del IPn Carr.Mty-Saltillo km.13 Ramos Arizpe Coah.CP.25900 Mexico

Transient liquid phase （TLP） bonding of 304 stainless steel with nickel based filler metal, Bni-9, was performed to study the influence of silicon nanoparticles （nPs） on the mechanical and structural properties of the bonding area. It was found that silicon nPs act as a melting point depressant in the brazing process; the formation of silicon TLP induces the dissolution of elements of the metal filler and promotes a uniform distribution in the bonding area. Silicon nPs induce the development of smaller eutectic structures in the melting zone; it has been related to microhardness measurements, which are lower when the silicon nPs are used in the brazing process.

关键词： Brazing nanoparticles Silicon Stainless steel

non-polynomial Zig-Zag and ESL shear deformation theory to study advanced composites

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Chinese Journal of Aeronautics 2019年第4期32卷 906-920页

作者： J.L.MAnTARI I.A.RAMOS J.C.MOnGE Faculty of Mechanical engineering Instituto de investigación en ingeniería naval(IDIIN)National University of Engineering(UNI)Lima 15333Peru department of Mechanical engineering University of New Mexico Faculty of Mechanical engineering Universidad de Ingeniería y Tecnología(UTEC)

The mechanical behavior of advanced composites can be modeled mathematically through unknown variables and Shear Strain Thickness Functions(SSTFs). Such SSTFs can be of polynomial or non-polynomial nature and some parameters of non-polynomial SSTFs can be optimized to get optimal results. In this paper, these parameters are called ‘‘r" and ‘‘s" and they are the argument of the trigonometric SSTFs introduced within the Carrera Unified Formulation(CUF). The Equivalent Single Layer(ESL) governing equations are obtained by employing the Principle of Virtual Displacement(PVD) and are solved using navier method solution. Furthermore, trigonometric expansion with Murakami theory was implemented in order to reproduce the Zig-Zag effects which are important for multilayer structures. Several combinations of optimization parameters are evaluated and selected by different criteria of average error. Results of the present unified trigonometrical theory with CUF bases confirm that it is possible to improve the stress and displacement results through the thickness distribution of models with reduced unknown variables. Since the idea is to find a theory with reduced numbers of unknowns, the present method appears to be an appropriate technique to select a simple model. However these optimization parameters depend on the plate geometry and the order of expansion or unknown variables. So, the topic deserves further research.

关键词： Analytical solution Composite materials CUF ESL Plate Trigonometric functions Zig-Zag effects