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Ubaldo Ortiz Méndez

Bio: Ubaldo Ortiz Méndez is an academic researcher from Universidad Autónoma de Nuevo León. The author has contributed to research in topics: Carbon nanotube & Scanning electron microscope. The author has an hindex of 11, co-authored 46 publications receiving 517 citations.

Papers
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Journal ArticleDOI
TL;DR: A review of the functionalization methods leading to soluble carbon nanotubes can be found in this article, where the authors focus on macrocycles, biomolecules, and polymers, as well as using such special techniques as use of radionuclides, irradiation, microwave treatment, or pulsed streamer discharge.
Abstract: Recent literature (2000−2008) on the functionalization methods leading to soluble carbon nanotubes is reviewed. Carbon nanotubes (CNTs) can be solubilized by a series of methods, including their functionalization by the aryl diazonium process, use of elemental metals, simple inorganics, acids, esters, aldehydes, amines, aromatics, macrocycles, thiols, biomolecules, polymers, and using such techniques as pulsed streamer discharge, microwave treatment, cryogenic crushing, or γ-irradiation. In a difference with the functionalization methods applied in the past decade of the 20th century (frequent use of strong acidic media as a first step and further attachment of various organic moieties), current techniques involve a much wider number of functionalizing agents paying main attention to macrocycles, biomolecules, and polymers, as well as using such special techniques as use of radionuclides, irradiation, microwave treatment, or pulsed streamer discharge. Reactivity, physicochemical properties, and main appli...

160 citations

Reference BookDOI
06 Feb 2013
TL;DR: A comprehensive handbook describing all possible radiation-chemistry interactions between irradiation and materials, the preparation of materials under distinct radiation types, and the possibility of damage of material can be found in this article.
Abstract: Researchers and engineers working in nuclear laboratories, nuclear electric plants, and elsewhere in the radiochemical industries need a comprehensive handbook describing all possible radiation-chemistry interactions between irradiation and materials, the preparation of materials under distinct radiation types, the possibility of damage of material

60 citations

Journal ArticleDOI
TL;DR: In this paper, a review of recent publications on C60- and C70-fulleropyrrolidines is presented, focusing on a series of novel dyads and triads with porphyrins and their metal complexes, ferrocene derivatives, S-containing ligands, calixarenes, crown-ethers, polymers, and enzymes.
Abstract: Recent publications on C60- and C70-fulleropyrrolidines are reviewed. Main attention is paid to a series of novel dyads and triads with porphyrins and their metal complexes, ferrocene derivatives, S-containing ligands, calixarenes, crown-ethers, polymers, and enzymes, as well as to relatively simple ligand systems. A certain attention is paid to fulleropyrrolidine polyadducts, multifullerenopyrrolidines, and functionalization of carbon nanotubes with pyrrolidine-containing moieties. Synthesis techniques, physicochemical methods to study the compounds obtained, and their main applications are examined. Representative examples for synthesis and applications are tabulated.

49 citations

Journal ArticleDOI
TL;DR: In this article, the synthesis, properties, and applications of ultrasmall particles (USPs, size/diameter <10 nm), so-called "ultrasmall nanoparticles" are reviewed.
Abstract: Synthesis, properties, and applications of ultrasmall particles (USPs, size/diameter <10 nm), so-called “ultrasmall nanoparticles”, are reviewed USPs mainly consist of nanoparticles (with or without functionalization) of metallic gold, as well as iron and gadolinium oxides, all of which have important biomedical applications Several other elemental metals and non-metals, oxides, salts, a few polymers and coordination compounds have also been obtained as USPs Their main applications include biomedical uses {Magnetic Resonance Imaging (MRI) contract agents, virus inactivation, immunoassay labeling, etc}, varieties of catalysis, hydrogen sorption, as magnetic devices, ultrasmall transistors, sensors for gases or biological objects, parts of solar cells and batteries, among others Recent approaches, such as size-focusing methodology, for obtaining USPs and preventing their further agglomeration, are discussed

44 citations

Journal ArticleDOI
TL;DR: In this paper, modern methods for external decoration of carbon nanotubes (CNTs) with elemental metal nanoparticles are reviewed, including indirect and direct physicochemical and physical methods mainly with noble and transition metals.
Abstract: Modern methods for external decoration of carbon nanotubes (CNTs) with elemental metal nanoparticles are reviewed. Carbon nanotubes can be decorated by indirect and direct physicochemical and physical methods mainly with noble and transition metals. The fabricated nanocomposites possess a series of useful applications in the fields of fuel cells, chemo/biosensors, solar cells, drug delivery, catalysis, and hydrogen storage. The first principal calculations and other related theoretical studies on these metal-CNTs nanohybrids are discussed.

39 citations


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Journal ArticleDOI
TL;DR: This review summarizes the major progress in the field, including the principles that permit atomically precise synthesis, new types of atomic structures, and unique physical and chemical properties ofatomically precise nanoparticles, as well as exciting opportunities for nanochemists to understand very fundamental science of colloidal nanoparticles.
Abstract: Colloidal nanoparticles are being intensely pursued in current nanoscience research. Nanochemists are often frustrated by the well-known fact that no two nanoparticles are the same, which precludes the deep understanding of many fundamental properties of colloidal nanoparticles in which the total structures (core plus surface) must be known. Therefore, controlling nanoparticles with atomic precision and solving their total structures have long been major dreams for nanochemists. Recently, these goals are partially fulfilled in the case of gold nanoparticles, at least in the ultrasmall size regime (1–3 nm in diameter, often called nanoclusters). This review summarizes the major progress in the field, including the principles that permit atomically precise synthesis, new types of atomic structures, and unique physical and chemical properties of atomically precise nanoparticles, as well as exciting opportunities for nanochemists to understand very fundamental science of colloidal nanoparticles (such as the s...

2,144 citations

Journal ArticleDOI
TL;DR: In this article, the authors organize the CO2 sorbents according to their working temperatures by classifying them as such: (1) low-temperature ( 400 °C), since the sorption capacity, kinetics, recycling stability and cost are important parameters when evaluating a sorbent.
Abstract: Carbon dioxide (CO2) capture using solid sorbents has been recognized as a very promising technology that has attracted intense attention from both academic and industrial fields in the last decade. It is astonishing that around 2000 papers have been published from 2011 to 2014 alone, which is less than three years after our first review paper in this journal on solid CO2 sorbents was published. In this short period, much progress has been made and the major research focus has more or less changed. Therefore, we feel that it is necessary to give a timely update on solid CO2 capture materials, although we still have to keep some important literature results published in the past years so as to keep the good continuity. We believe this work will benefit researchers working in both academic and industrial areas. In this paper, we still organize the CO2 sorbents according to their working temperatures by classifying them as such: (1) low-temperature ( 400 °C). Since the sorption capacity, kinetics, recycling stability and cost are important parameters when evaluating a sorbent, these features will be carefully considered and discussed. In addition, due to the huge amounts of cost-effective CO2 sorbents demanded and the importance of waste resources, solid CO2 sorbents prepared from waste resources and their performance are reviewed. Finally, the techno-economic assessments of various CO2 sorbents and technologies in real applications are briefly discussed.

901 citations

Journal ArticleDOI
TL;DR: This critical review describes the methods that are used for electrografting, their mechanism, the formation and growth of the layers as well as their applications.
Abstract: Electrografting refers to the electrochemical reaction that permits organic layers to be attached to solid conducting substrates. This definition can be extended to reactions involving an electron transfer between the substrate to be modified and the reagent, but also to examples where a reducing or oxidizing reagent is added to produce the reactive species. These methods are interesting as they provide a real bond between the surface and the organic layer. Electrografting applies to a variety of substrates including carbon, metals and their oxides, but also dielectrics such as polymers. Since the 1980s several methods have been developed, either by reduction or oxidation, and some of them have reached an industrial stage. This critical review describes the methods that are used for electrografting, their mechanism, the formation and growth of the layers as well as their applications (742 references).

834 citations

Journal ArticleDOI
TL;DR: In this article, the authors focus on the separation of carbon dioxide from typical power plant exhaust gases using the adsorption process, which is believed to be one of the economic and least interfering ways for post-combustion carbon capture as it can accomplish the objective with very few modifications to power plants.

469 citations

Journal ArticleDOI
TL;DR: In this paper, the role of catalyst evolution and the mechanistic picture of cocktail-type systems are considered from the perspective of the development of a new generation of efficient, selective and re-usable catalysts for synthetic applications.

271 citations