keyword
MENU ▼
Read by QxMD icon Read
search

nano catalysis

keyword
https://www.readbyqxmd.com/read/28723102/insight-into-copper-catalysis-in-situ-formed-nano-cu2o-in-suzuki-miyaura-cross-coupling-of-aryl-indolyl-boronates
#1
Ganapathy Ranjani, Rajagopal Nagarajan
A ligand-free copper catalyzed Suzuki-Miyaura coupling of 3,5-diiodopyridine with aryl and indole boronates has been explored in good to excellent yields. In situ generation of nano-Cu2O from CuCl2 under the reaction conditions has been discovered for the first time. The generality of the reaction was further demonstrated by the arylation of 5-iodopyrimidine, iodopyridines, iodobenzenes, and diiodobenzenes and resulted in good to moderate yields. Moreover, bisindole alkaloid Scalaridine A has been successfully synthesized in 60% overall yield...
July 19, 2017: Organic Letters
https://www.readbyqxmd.com/read/28723090/transformative-heterointerface-evolution-and-plasmonic-tuning-of-anisotropic-trimetallic-nanoparticles
#2
Mouhong Lin, Gyeong-Hwan Kim, Jae-Ho Kim, Jeong-Wook Oh, Jwa-Min Nam
Multi-component nanoparticles that incorporate multiple nano-crystal domains into a single particle represent an important class of material with highly tailorable structures and properties. The controlled synthesis of multi-component NPs with 3 or more components with the desired structure, particularly aniso-tropic structures, and property is, however, highly challenging. Here, we developed a polymer and galvanic replacement reac-tion-based transformative heterointerface evolution (THE) method to form and tune gold-copper-silver multi-metallic ani-sotropic nanoparticles (MAPs) with well-defined configurations, including structural order, uniformity and junction geometry, giving rise to extraordinarily high tunability in the structural design, synthesis and optical property of tri-metallic plasmonic nanoantenna structures...
July 19, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28721537/controlling-activation-barrier-by-carbon-nanotubes-as-nano-chemical-reactors
#3
Alia Méjri, Fabien Picaud, Mohammed El Khalifi, Tijani Gharbi, Bahoueddine Tangour
The oxidative addition of primary amine on a monocyclic phospholane was studied in confined conditions. This one-step chemical reaction has been investigated using the DFT technique to elucidate the role of confinement in carbon nanotubes on the reaction. Calculations were carried out by a progressive increase of the nanotube diameters from 10 Å to 15 Å in order to highlight the dependence of the reactivity on the nanotube diameter. First, single point investigations were dedicated to the study of reactants, transition states, and products placed in the different nanotubes while keeping their optimized structure as free compounds...
August 2017: Journal of Molecular Modeling
https://www.readbyqxmd.com/read/28713885/synergistic-effect-of-au-ag-nano-alloying-intense-seira-and-enhanced-catalysis
#4
Manoj Verma, M Boazbou Newmai, P Senthil Kumar
The well-known AuAg nanohybrid system was effectively synthesized, utilizing polyvinyl pyrrolidone (PVP) as a multiple metal precursor reducing agent (based solely on their reduction potentials), thereby drastically decreasing their activation energy of diffusion and readily facilitating the homogenous alloy nanoparticle formation, duly confirmed by Vegard's law. Furthermore, the crucial parameters in determining the local electric field enhancement in the vicinity of the alloy nanoparticles such as the quality factor Q, dephasing time, T2 and the homogenous line width Γ were also evaluated in a systematic manner, in correlation with their unique visible optical absorption spectra...
July 17, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28699627/nano-palladium-is-a-cellular-catalyst-for-in-vivo-chemistry
#5
Miles A Miller, Bjorn Askevold, Hannes Mikula, Rainer H Kohler, David Pirovich, Ralph Weissleder
Palladium catalysts have been widely adopted for organic synthesis and diverse industrial applications given their efficacy and safety, yet their biological in vivo use has been limited to date. Here we show that nanoencapsulated palladium is an effective means to target and treat disease through in vivo catalysis. Palladium nanoparticles (Pd-NPs) were created by screening different Pd compounds and then encapsulating bis[tri(2-furyl)phosphine]palladium(II) dichloride in a biocompatible poly(lactic-co-glycolic acid)-b-polyethyleneglycol platform...
July 12, 2017: Nature Communications
https://www.readbyqxmd.com/read/28684914/regulation-of-apoptosis-through-bcl-2-bax-proteins-expression-and-dna-damage-by-nano-sized-gadolinium-oxide
#6
Saud Alarifi, Huma Ali, Saad Alkahtani, Mohammed S Alessia
Gadolinium oxide (Gd2O3) nanoparticles (GNPs) are applied in industrial products, for example, additives, optical glass, and catalysis. There are various suggestions of metal nanoparticles paradigm but the underlying basic mechanism about the toxicity of metal nanoparticles, for example GNPs, remains unclear. This experiment was done to measure the effective toxicity of GNPs (10, 25, 50, and 100 µg/mL) over 24 and 48 h and to evaluate toxicity mechanism in human neuronal (SH-SY5Y) cells. GNPs produced reactive oxygen species (ROS), as evaluated by 2', 7'-dichlorodihydrofluorescein diacetate...
2017: International Journal of Nanomedicine
https://www.readbyqxmd.com/read/28671708/silica-based-hierarchical-porous-janus-microcapsules-construction-and-support-of-au-nano-particle-catalyst-inside
#7
Xia Kong, Changcheng Wu, Lei Feng, Jiayan Qu, Pange Liu, Xiaomei Wang, Xu Zhang
A facile and novel method was developed to fabricate silica-based hierarchical porous Janus microcapsules (HPJMs SiO2) for catalysis. The resulting Au@HPJMs SiO2 nanocomposites showed enhanced catalysis, great stability, convenient recovery and reuse without losing catalytic efficiency.
July 3, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28665585/cryotem-as-an-advanced-analytical-tool-for-materials-chemists
#8
Joseph P Patterson, Yifei Xu, Mohammad-Amin Moradi, Nico A J M Sommerdijk, Heiner Friedrich
Morphology plays an essential role in chemistry through the segregation of atoms and/or molecules into different phases, delineated by interfaces. This is a general process in materials synthesis and exploited in many fields including colloid chemistry, heterogeneous catalysis, and functional molecular systems. To rationally design complex materials, we must understand and control morphology evolution. Toward this goal, we utilize cryogenic transmission electron microscopy (cryoTEM), which can track the structural evolution of materials in solution with nanometer spatial resolution and a temporal resolution of <1 s...
June 30, 2017: Accounts of Chemical Research
https://www.readbyqxmd.com/read/28661517/integrative-self-sorting-of-coordination-cages-based-on-naked-metal-ions
#9
Witold M Bloch, Guido H Clever
Coordination-driven self-assembly of metal ions and organic ligands has been extensively utilised over the past four decades to access a variety of nano-sized cage assemblies, with functions ranging from sensing and catalysis to drug delivery. Many of the reported examples, however, are highly symmetric architectures that contain one type of organic ligand carrying not more than a single functionality. This contrasts significantly with the level of structural and functional complexity encountered in biological macromolecular hosts, which are able to bind and chemically convert smaller molecules in their highly-decorated internal cavities...
June 29, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28661074/a-review-of-recent-developments-of-mesoporous-materials
#10
REVIEW
Steven L Suib
This personal account concerns novel recent discoveries in the area of mesoporous materials. Most of the papers discussed have been published within the last two to three years. A major emphasis of most of these papers is the synthesis of unique mesoporous materials by a variety of synthetic methods. Many of these articles focus on the control of the pore sizes and shapes of mesoporous materials. Synthetic methods of various types have been used for such control of porosity including soft templating, hard templating, nano-casting, electrochemical methods, surface functionalization, and trapping of species in pores...
June 29, 2017: Chemical Record: An Official Publication of the Chemical Society of Japan ... [et Al.]
https://www.readbyqxmd.com/read/28630331/distinguishing-attosecond-electron-electron-scattering-and-screening-in-transition-metals
#11
Cong Chen, Zhensheng Tao, Adra Carr, Piotr Matyba, Tibor Szilvási, Sebastian Emmerich, Martin Piecuch, Mark Keller, Dmitriy Zusin, Steffen Eich, Markus Rollinger, Wenjing You, Stefan Mathias, Uwe Thumm, Manos Mavrikakis, Martin Aeschlimann, Peter M Oppeneer, Henry Kapteyn, Margaret Murnane
Electron-electron interactions are the fastest processes in materials, occurring on femtosecond to attosecond timescales, depending on the electronic band structure of the material and the excitation energy. Such interactions can play a dominant role in light-induced processes such as nano-enhanced plasmonics and catalysis, light harvesting, or phase transitions. However, to date it has not been possible to experimentally distinguish fundamental electron interactions such as scattering and screening. Here, we use sequences of attosecond pulses to directly measure electron-electron interactions in different bands of different materials with both simple and complex Fermi surfaces...
June 19, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28624746/textual-properties-and-catalytic-performances-of-halloysite-hybrid-ceo2-zro2-nanoparticles
#12
Jing Ouyang, Zai Zhao, Yi Zhang, Huaming Yang
Halloysite (Hal) hybridized ceria-zirconia solid solution material (CZ-Hal) for three way catalysis was synthesized through co-precipitation method. X-ray diffraction (XRD), N2 adsorption-desorption isotherms, transmission electronic microscopy (TEM), scanning electronic microscopy (SEM), X-ray energy dispersion spectrum (EDS), and temperature-programmed H2 reduction (H2-TPR) were used to characterize the crystalline, textural, morphological, and reducibility of the products. The three way catalytic performances of the supported products was tested in stoichiometric air/fuel condition...
June 9, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/28574712/tracking-single-dna-nanodevices-in-hierarchically-meso-macroporous-antimony-doped-tin-oxide-demonstrates-finite-confinement
#13
Daniel Mieritz, Xiang Li, Alex Volosin, Minghui Liu, Hao Yan, Nils G Walter, Dong-Kyun Seo
Housing bio-nano guest devices based on DNA nanostructures within porous, conducting, inorganic host materials promise valuable applications in solar energy conversion, chemical catalysis, and analyte sensing. Herein, we report a single-template synthetic development of hierarchically porous, transparent conductive metal oxide coatings whose pores are freely accessible by large biomacromolecules. Their hierarchal pore structure is bimodal with a larger number of closely packed open macropores (∼200 nm) at the higher rank and with the remaining space being filled with a gel network of antimony-doped tin oxide (ATO) nanoparticles that is highly porous with a broad size range of textual pores mainly from 20-100 nm at the lower rank...
June 14, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28567259/photothermal-enhanced-catalysis-in-core-shell-plasmonic-hierarchical-cu7s4-microsphere-zeolitic-imidazole-framework-8
#14
Feifan Wang, Yanjie Huang, Zhigang Chai, Min Zeng, Qi Li, Yuan Wang, Dongsheng Xu
Conventional semiconductor photocatalysis based on band-edge absorption remains inefficient due to the limited harvesting of solar irradiation and the complicated surface/interface chemistry. Herein, novel photothermal-enhanced catalysis was achieved in a core-shell hierarchical Cu7S4 nano-heater@ZIF-8 heterostructures via near-infrared localized surface plasmon resonance. Our results demonstrated that both the high surface temperature of the photothermal Cu7S4 core and the close-adjacency of catalytic ZIF-8 shell contributed to the extremely enhanced catalytic activity...
December 1, 2016: Chemical Science
https://www.readbyqxmd.com/read/28537615/constructing-three-dimensional-porous-ni-ni3s2-nano-interfaces-for-hydrogen-evolution-electrocatalysis-under-alkaline-conditions
#15
Yiming An, Bolong Huang, Zilong Wang, Xia Long, Yongcai Qiu, Jue Hu, Dan Zhou, He Lin, Shihe Yang
It is still a challenging issue to design earth-abundant electrocatalysts with low cost, high activity and long-term stability for the hydrogen evolution reaction (HER) based on water splitting in alkaline solutions. Here, we report a facile synthetic route for a three-dimensional, porous Ni/Ni3S2 nano-network on carbon cloth for the efficient catalysis of HER. This unique structure exposes a high proportion of Ni/Ni3S2 hetero-interfaces to the electrolyte, creating a synergetic effect between Ni and Ni3S2 that enhances HER...
May 24, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28500946/pa-tb-cu-mof-as-luminescent-nanoenzyme-for-catalytic-assay-of-hydrogen-peroxide
#16
Zewan Qi, Li Wang, Qi You, Yang Chen
Metal organic frameworks (MOFs) with flexible structures and components have aroused great interest in designing functional materials. In this work, we designed and made a kind of PA-Tb-Cu MOF nanoenzyme capable of emitting fluorescence for the catalytic reaction of hydrogen peroxide (H2O2). Luminescent Tb(3+), catalytic Cu(2+) and bridging ligand were assembled and integrated into a single material nanoenzyme. This PA-Tb-Cu MOF nanoenzyme not only possessed excellent catalytic activity comparable to horseradish peroxidase but also can real-time fluorescently indicate the concentration of H2O2 as low as 0...
May 6, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28447779/performance-and-mechanism-of-piezo-catalytic-degradation-of-4-chlorophenol-finding-of-effective-piezo-dechlorination
#17
Shenyu Lan, Jinxi Feng, Ya Xiong, Shuanghong Tian, Shengwei Liu, Lingjun Kong
Piezo-catalysis was first used to degrade a nondye pollutant, 4-chlorophenol (4-CP). In this process, hydrothermally synthesized tetragonal BaTiO3 nano/micrometer-sized particles were used as the piezo-catalyst, and the ultrasonic irradiation with low frequency was selected as the vibration energy to cause the deformation of tetragonal BaTiO3. It was found that the piezoelectric potential from the deformation could not only successfully degrade 4-chlorophenol but also effectively dechlorinate it at the same time, and five kinds of dechlorinated intermediates, hydroquinone, benzoquinone, phenol, cyclohexanone, and cyclohexanol, were determined...
June 6, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28443627/multifunctionality-of-silver-closo-boranes
#18
Mark Paskevicius, Bjarne R S Hansen, Mathias Jørgensen, Bo Richter, Torben R Jensen
Silver compounds share a rich history in technical applications including photography, catalysis, photocatalysis, cloud seeding and as antimicrobial agents. Here we present a class of silver compounds (Ag2B10H10 and Ag2B12H12) that are semiconductors with a bandgap at 2.3 eV in the green visible light spectrum. The silver boranes have extremely high ion conductivity and dynamic-anion facilitated Ag(+) migration is suggested based on the structural model. The ion conductivity is enhanced more than two orders of magnitude at room temperature (up to 3...
April 26, 2017: Nature Communications
https://www.readbyqxmd.com/read/28426059/evolution-of-dealloying-induced-strain-in-nanoporous-gold-crystals
#19
Yu-Chen Karen Chen-Wiegart, Ross Harder, David C Dunand, Ian McNulty
We studied the evolution of dealloying-induced strain along the {111} in a Ag-Au nano-crystal in situ, during formation of nanoporous gold at the initial stage of dealloying using Bragg coherent X-ray diffractive imaging. The strain magnitude with maximum probability in the crystal doubled in 10 s of dealloying. Although formation of nano-pores just began at the surface, the greatest strain is located 60-80 nm deep within the crystal. Dealloying induced a compressive strain in this region, indicating volume shrinkage occurred during pore formation...
May 4, 2017: Nanoscale
https://www.readbyqxmd.com/read/28395134/facile-fabrication-of-bcn-nanosheet-encapsulated-nano-iron-as-highly-stable-fischer-tropsch-synthesis-catalyst
#20
Jianghong Wu, Liancheng Wang, Baoliang Lv, Jiangang Chen
The few layered boron carbon nitride nanosheets (BCNNSs) have attracted widespread attention in the field of heterogeneous catalysis. Herein, we report an innovative one-pot route to prepare the catalyst of BCNNSs-encapsulated sub-10 nm highly dispersed nanoiron particles. Then the novel catalyst was used in Fischer-Tropsch synthesis for the first time and it exhibited high activity and superior stability. At a high temperature of 320 °C, CO conversion could reach 88.9%, corresponding catalytic activity per gram of iron (iron time yield, FTY) of 0...
April 14, 2017: ACS Applied Materials & Interfaces
keyword
keyword
68168
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"