1
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Lednev VN, Sdvizhenskii PA, Grishin MY, Fedorov AN, Khokhlova OV, Oshurko VB, Pershin SM. Optimizing laser crater enhanced Raman scattering spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 196:31-39. [PMID: 29428894 DOI: 10.1016/j.saa.2018.01.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 01/24/2018] [Accepted: 01/25/2018] [Indexed: 06/08/2023]
Abstract
The laser crater enhanced Raman scattering (LCERS) spectroscopy technique has been systematically studied for chosen sampling strategy and influence of powder material properties on spectra intensity enhancement. The same nanosecond pulsed solid state Nd:YAG laser (532 nm, 10 ns, 0.1-1.5 mJ/pulse) was used for laser crater production and Raman scattering experiments for l-aspartic acid powder. Increased sampling area inside crater cavity is the key factor for Raman signal improvement for the LCERS technique, thus Raman signal enhancement was studied as a function of numerous experimental parameters including lens-to-sample distance, wavelength (532 and 1064 nm) and laser pulse energy utilized for crater production. Combining laser pulses of 1064 and 532 nm wavelengths for crater ablation was shown to be an effective way for additional LCERS signal improvement. Powder material properties (particle size distribution, powder compactness) were demonstrated to affect LCERS measurements with better results achieved for smaller particles and lower compactness.
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Affiliation(s)
- V N Lednev
- Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, Russia; National University of Science and Technology MISIS, Moscow, Russia.
| | - P A Sdvizhenskii
- National University of Science and Technology MISIS, Moscow, Russia
| | - M Ya Grishin
- Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, Russia; Moscow Institute of Physics and Technology (State University), Dolgoprudny, Russia
| | - A N Fedorov
- Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, Russia
| | - O V Khokhlova
- National University of Science and Technology MISIS, Moscow, Russia
| | - V B Oshurko
- Moscow State University of Technology "Stankin", Moscow, Russia
| | - S M Pershin
- Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, Russia
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2
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Jankovský O, Lojka M, Luxa J, Sedmidubský D, Tomanec O, Zbořil R, Pumera M, Sofer Z. Selective Bromination of Graphene Oxide by the Hunsdiecker Reaction. Chemistry 2017; 23:10473-10479. [PMID: 28543831 DOI: 10.1002/chem.201702031] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Indexed: 11/06/2022]
Abstract
Halogenated graphenes have been attracting great attention in the recent years. The currently used methods are usually non-specific, and halogen groups are randomly distributed over the graphene. Here we demonstrate a selective graphene functionalization based on a well known reaction mechanism-Hunsdiecker reaction-applied on selective bromination of graphene oxide. The chemical analysis using various spectroscopic methods proved a high efficiency of this functionalization method. Bromination can be carried out under mild conditions without any high temperature or high pressure treatment. The chemical modification led to introduction of up to 20 wt.% of bromine covalently bonded to the graphene skeleton. The modified graphene was characterized in detail using a broad range of microscopic and spectroscopic methods and no significant contamination by reaction by-products was detected.
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Affiliation(s)
- Ondřej Jankovský
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, 166 28, Prague 6, Czech Republic
| | - Michal Lojka
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, 166 28, Prague 6, Czech Republic
| | - Jan Luxa
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, 166 28, Prague 6, Czech Republic
| | - David Sedmidubský
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, 166 28, Prague 6, Czech Republic
| | - Ondřej Tomanec
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University Olomouc, Šlechtitelů 11, 783 71, Olomouc, Czech Republic
| | - Radek Zbořil
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University Olomouc, Šlechtitelů 11, 783 71, Olomouc, Czech Republic
| | - Martin Pumera
- Division of Chemistry & Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Zdeněk Sofer
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, 166 28, Prague 6, Czech Republic
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3
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Kumar S, Rani R, Dilbaghi N, Tankeshwar K, Kim KH. Carbon nanotubes: a novel material for multifaceted applications in human healthcare. Chem Soc Rev 2017; 46:158-196. [DOI: 10.1039/c6cs00517a] [Citation(s) in RCA: 263] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Remarkable advances achieved in modern material technology, especially in device fabrication, have facilitated diverse materials to expand the list of their application fields.
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Affiliation(s)
- Sandeep Kumar
- Department of Bio and Nano Technology
- Guru Jambheshwar University of Science and Technology
- Hisar
- India
| | - Ruma Rani
- Department of Bio and Nano Technology
- Guru Jambheshwar University of Science and Technology
- Hisar
- India
| | - Neeraj Dilbaghi
- Department of Bio and Nano Technology
- Guru Jambheshwar University of Science and Technology
- Hisar
- India
| | - K. Tankeshwar
- Department of Bio and Nano Technology
- Guru Jambheshwar University of Science and Technology
- Hisar
- India
- Department of Physics
| | - Ki-Hyun Kim
- Department of Civil & Environmental Engineering
- Hanyang University
- Seoul 04763
- Republic of Korea
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4
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Bouša D, Luxa J, Mazánek V, Jankovský O, Sedmidubský D, Klímová K, Pumera M, Sofer Z. Toward graphene chloride: chlorination of graphene and graphene oxide. RSC Adv 2016. [DOI: 10.1039/c6ra14845j] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Chlorinated graphene derivates with chlorine concentration exceeding 11 at% were synthesized by high temperature exfoliation in chlorine atmosphere. Halogen graphenes have a great potential for electronic and electrochemical devices.
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Affiliation(s)
- D. Bouša
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - J. Luxa
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - V. Mazánek
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - O. Jankovský
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - D. Sedmidubský
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - K. Klímová
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - M. Pumera
- Division of Chemistry & Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore
- Singapore
| | - Z. Sofer
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
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5
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Bouša D, Luxa J, Sedmidubský D, Huber Š, Jankovský O, Pumera M, Sofer Z. Nanosized graphane (C1H1.14)n by hydrogenation of carbon nanofibers by Birch reduction method. RSC Adv 2016. [DOI: 10.1039/c5ra22077g] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Fully hydrogenated graphane nanostructures were prepared from graphite nanofibers by Birch reduction reaction.
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Affiliation(s)
- Daniel Bouša
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - Jan Luxa
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - David Sedmidubský
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - Štěpán Huber
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - Ondřej Jankovský
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
| | - Martin Pumera
- Division of Chemistry & Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore
- Singapore
| | - Zdeněk Sofer
- Department of Inorganic Chemistry
- University of Chemistry and Technology Prague
- 166 28 Prague 6
- Czech Republic
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6
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Faria J, Pilar Ruiz M, Resasco DE. Carbon Nanotube/Zeolite Hybrid Catalysts for Glucose Conversion in Water/Oil Emulsions. ACS Catal 2015. [DOI: 10.1021/acscatal.5b00559] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jimmy Faria
- Abengoa Research, Campus Palmas
Altas c/Energía Solar n° 1, Palmas Altas, Seville 41014, Spain
| | - M. Pilar Ruiz
- Abengoa Research, Campus Palmas
Altas c/Energía Solar n° 1, Palmas Altas, Seville 41014, Spain
| | - Daniel E. Resasco
- School
of Chemical, Biological and Materials Engineering and Center of Interfacial
Reaction Engineering (CIRE), University of Oklahoma, Norman, Oklahoma 73019, United States
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7
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Mohamed MM. Gold loaded titanium dioxide–carbon nanotube composites as active photocatalysts for cyclohexane oxidation at ambient conditions. RSC Adv 2015. [DOI: 10.1039/c5ra05253j] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Photocatalytic oxidation of neat cyclohexane with H2O2 was carried out using several types of gold modified materials including titania nanotubes, reduced graphene oxide and titania nanotube–multiwalled carbon nanotube composites under UV irradiation.
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8
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Makama AB, Salmiaton A, Abdullah N, Choong TSY, Saion EB. Recent Developments in Purification of Single Wall Carbon Nanotubes. SEP SCI TECHNOL 2014. [DOI: 10.1080/01496395.2013.815628] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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9
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Liu JH, Yang ST, Wang X, Wang H, Liu Y, Luo PG, Liu Y, Sun YP. Carbon nanoparticles trapped in vivo-similar to carbon nanotubes in time-dependent biodistribution. ACS APPLIED MATERIALS & INTERFACES 2014; 6:14672-14678. [PMID: 25068474 DOI: 10.1021/am504022s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Carbon nanoparticles are in all of the carbon nanomaterials that are presently widely pursued for potential bioapplications, but their in vivo biodistribution-related properties are largely unknown. In this work, highly (13)C-enriched carbon nanoparticles were prepared to allow their quantification in biological samples by using isotope-ratio mass spectroscopy. The in vivo biodistribution results are presented and discussed, and also compared with those of the aqueous suspended carbon nanotubes reported previously. The distribution profile and time dependencies are largely similar between the nanoparticles and nanotubes, with results on both suggesting meaningful accumulation in some major organs over an extended period of time. Therefore, the surface modification of carbon nanoparticles, preferably the chemical functionalization of the nanoparticles with biocompatible molecules or species, is desirable or necessary in the pursuit of these nanomaterials for various bioapplications.
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Affiliation(s)
- Jia-Hui Liu
- Institute of Nanochemistry and Nanobiology, Shanghai University , Shanghai 200444, China
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10
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Synthesis and optical enhancement of amorphous carbon nanotubes/silver nanohybrids via chemical route at low temperature. ScientificWorldJournal 2014; 2014:847806. [PMID: 24995365 PMCID: PMC4068040 DOI: 10.1155/2014/847806] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 05/10/2014] [Accepted: 05/12/2014] [Indexed: 11/17/2022] Open
Abstract
We report the synthesis of amorphous carbon nanotubes/silver (αCNTs/Ag) nanohybrids via simple chemical route without additional reactant and surfactant at low temperature. Field emission scanning microscope (FESEM) and transmission electron microscope (TEM) confirmed formation of CNTs. X-ray diffraction (XRD) pattern confirmed the amorphous phase of carbon and the formation of Ag nanoparticles crystalline phase. Raman spectra revealed the amorphous nature of α CNTs. UV-visible spectroscopy showed enhancement of optical properties of α CNTs/Ag nanohybrids.
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11
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Nguendia JZ, Zhong W, Fleury A, De Grandpré G, Soldera A, Sabat RG, Claverie JP. Supramolecular complexes of multivalent cholesterol-containing polymers to solubilize carbon nanotubes in apolar organic solvents. Chem Asian J 2014; 9:1356-64. [PMID: 24596341 DOI: 10.1002/asia.201301687] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Indexed: 11/07/2022]
Abstract
Copolymers of 2-ethylhexyl acrylate (EHA) and cholesteryloxycarbonyl-2-hydroxymethacrylate (CEM) were prepared by reversible addition-fragmentation chain-transfer (RAFT) polymerization. Supramolecular complexes of these copolymers with carbon nanotubes (CNTs) were soluble in THF, toluene, and isooctane. The colloidal solutions remained stable for months without aggregation. The rationale for the choice of CEM was based on the high adsorption energy of cholesterol on the CNT surface, as computed by DFT calculations. Adsorption isotherms were experimentally measured for copolymers of various architectures (statistical, diblock, and star copolymers), thereby demonstrating that 2-5 cholesterol groups were adsorbed per polymer chain. Once the supramolecular complex had dried, the CNTs could be easily resolubilized in isooctane without the need for high-power sonication and in the absence of added polymer. Analysis by atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) indicated that the CNTs were devoid of bundles. The supramolecular complexes could also be employed in an inverse emulsion polymerization of 2-hydroxyethylmethacrylate (HEMA) in isooctane and dodecane, thereby leading to the formation of a continuous polymeric sheath around the CNTs. Thus, this technique leads to the formation of very stable dispersions in non-polar organic solvents, without altering the fundamental properties of the CNTs.
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Affiliation(s)
- Jules Zeuna Nguendia
- Quebec Center for Functional Materials, NanoQAM, Department of Chemistry, Université du Québec à Montréal, Succ. Centre-Ville, CP8888, Montreal, H3C3P8 Qc (Canada)
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12
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Pierlot AP, Woodhead AL, Church JS. Thermal annealing effects on multi-walled carbon nanotube yarns probed by Raman spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 117:598-603. [PMID: 24103230 DOI: 10.1016/j.saa.2013.09.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 08/30/2013] [Accepted: 09/07/2013] [Indexed: 06/02/2023]
Abstract
The realized mechanical properties of CNT macrostructures such as webs and yarns remain significantly lower than those of the individual CNTs. Structural changes induced by thermal annealing under inert atmosphere were assessed using Raman spectroscopy. Annealing above 1000 °C resulted in a marked decrease in the D/G ratio which can be attributed to an increase in the crystallite size or the distance between defects. The band component parameters obtained by spectral deconvolution reveal that the D band peak maximum shifts to slightly higher energy with increased annealing temperature. In contrast, the energy of the G band did not change. The full widths at half height (FWHH) of the D and G bands are seen to decrease with increasing annealing temperature. The tensile properties of the yarns have been investigated and it was found that the yarn tenacity did not improve with these structural changes. The effect of impurities in the annealing system such as oxygen, adsorbed water or organic surface contamination was also investigated.
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Affiliation(s)
- Anthony P Pierlot
- CSIRO Materials Science and Engineering, Waurn Ponds, Geelong, VIC 3216, Australia
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13
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Eng AYS, Sofer Z, Šimek P, Kosina J, Pumera M. Highly Hydrogenated Graphene through Microwave Exfoliation of Graphite Oxide in Hydrogen Plasma: Towards Electrochemical Applications. Chemistry 2013; 19:15583-92. [DOI: 10.1002/chem.201303164] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Indexed: 11/12/2022]
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14
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López-Lorente AI, Simonet BM, Valcárcel M. Qualitative detection and quantitative determination of single-walled carbon nanotubes in mixtures of carbon nanotubes with a portable Raman spectrometer. Analyst 2013; 138:2378-85. [DOI: 10.1039/c3an36566b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Eng AYS, Poh HL, Luxa J, Sofer Z, Pumera M. Potassium assisted reduction and doping of graphene oxides: towards faster electron transfer kinetics. RSC Adv 2013. [DOI: 10.1039/c3ra40758f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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16
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Preparation of few-layer and single-layer graphene by exfoliation of expandable graphite in supercritical N,N-dimethylformamide. J Supercrit Fluids 2012. [DOI: 10.1016/j.supflu.2012.01.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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17
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Zapata PA, Faria J, Pilar Ruiz M, Resasco DE. Condensation/Hydrogenation of Biomass-Derived Oxygenates in Water/Oil Emulsions Stabilized by Nanohybrid Catalysts. Top Catal 2012. [DOI: 10.1007/s11244-012-9768-4] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Kobayashi N, Naya M, Mizuno K, Yamamoto K, Ema M, Nakanishi J. Pulmonary and systemic responses of highly pure and well-dispersed single-wall carbon nanotubes after intratracheal instillation in rats. Inhal Toxicol 2011; 23:814-28. [PMID: 22004357 PMCID: PMC3251003 DOI: 10.3109/08958378.2011.614968] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The present study was conducted to assess the pulmonary and systemic responses in rats after intratracheal instillation of highly pure, well-dispersed, and well-characterized SWCNTs. Exposure to SWCNTs up to 2 mg/kg did not produce mortality, changes in clinical signs, or body weights during the observation period. Dose-dependent changes were observed in the lung weight, BALF inflammatory cells, and biochemical parameters such as LDH value, protein content, IL-1β and IL-6 activity, and histopathology. In the 0.04 mg/kg SWCNT-exposed group, almost no changes were observed during the observation period. In the 0.2 mg/kg SWCNT-exposed group, pulmonary inflammatory responses were observed after instillation. In the 1 mg/kg and 2 mg/kg SWCNT-exposed group, acute lung inflammation and subsequent granuloma accompanied by increased lung weights were observed. Furthermore, the histopathological findings in the lungs of rats exposed to SWCNTs showed inflammatory responses related with the vital reaction to the foreign substance that was instilled intratracheally, and there were no fibrosis, atypical lesion, or tumor-related findings even at the highest dose (2 mg/kg) of SWCNT-exposed groups up to 6 months after instillation. For all groups, histopathological changes due to the instillation exposure of SWCNTs were observed only in the lungs and lung-associated lymph nodes and not in the other tissues examined (i.e. the liver, kidney, spleen, and cerebrum).
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Affiliation(s)
- Norihiro Kobayashi
- Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
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19
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Ruiz MP, Faria J, Shen M, Drexler S, Prasomsri T, Resasco DE. Nanostructured carbon-metal oxide hybrids as amphiphilic emulsion catalysts. CHEMSUSCHEM 2011; 4:964-974. [PMID: 21751419 DOI: 10.1002/cssc.201000322] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Indexed: 05/31/2023]
Abstract
Nanohybrids composed of "onion-like" carbon, single-walled (SWCNTs) or multi-walled carbon nanotubes (MWCNTs) fused to silica or alumina particles have been compared as stabilizers of water/oil emulsions and interfacial catalysts. The amphiphilic character of these nanohybrids makes them effective in stabilizing emulsions (up to 85 % of total volume) comprising of small droplets (less than 40 μm). Furthermore, these nanohybrids have been used as supports for transition metal particles (palladium and copper) to catalyze reactions at the water/oil interface. Three different reaction systems have been conducted in the emulsions to demonstrate the principle: 1) hydrogenation of phenanthrene; 2) hydrogenation of glutaraldehyde and benzaldehyde; 3) oxidation of tetralin. Comparison of the maximum conversions achieved in emulsions as opposed to the single phase, together with much better control of selectivity in the two-phase system shows the benefits of using these nanohybrid catalysts.
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Affiliation(s)
- M Pilar Ruiz
- School of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, Oklahoma 73019, USA
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20
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Morimoto Y, Hirohashi M, Ogami A, Oyabu T, Myojo T, Todoroki M, Yamamoto M, Hashiba M, Mizuguchi Y, Lee BW, Kuroda E, Shimada M, Wang WN, Yamamoto K, Fujita K, Endoh S, Uchida K, Kobayashi N, Mizuno K, Inada M, Tao H, Nakazato T, Nakanishi J, Tanaka I. Pulmonary toxicity of well-dispersed multi-wall carbon nanotubes following inhalation and intratracheal instillation. Nanotoxicology 2011; 6:587-99. [PMID: 21714591 DOI: 10.3109/17435390.2011.594912] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Multi-walled carbon nanotubes (MWCNTs), dispersed in suspensions consisting mainly of individual tubes, were used for intratracheal instillation and inhalation studies. Rats intratracheally received a dose of 0.2 mg, or 1 mg of MWCNTs and were sacrificed from 3 days to 6 months. MWCNTs induced a pulmonary inflammation, as evidenced by a transient neutrophil response in the low-dose groups, and presence of small granulomatous lesion and persistent neutrophil infiltration in the high-dose groups. In the inhalation study, rats were exposed to 0.37 mg/m(3) aerosols of well-dispersed MWCNTs (>70% of MWCNTs were individual fibers) for 4 weeks, and were sacrificed at 3 days, 1 month, and 3 months after the end of exposure. The inhalation exposures delivered less amounts of MWCNTs into the lungs, and therefore less pulmonary inflammation responses was observed, as compared to intratracheal instillation. The results of our study show that well-dispersed MWCNT can produce pulmonary lesions, including inflammation.
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Affiliation(s)
- Yasuo Morimoto
- Institute of Industrial Ecological Sciences, School of Medicine, University of Occupational and Environment Health, Japan.
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21
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Zhang W, Silva SRP. Raman and FT-IR studies on dye-assisted dispersion and flocculation of single walled carbon nanotubes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 77:175-178. [PMID: 20570553 DOI: 10.1016/j.saa.2010.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 04/12/2010] [Accepted: 05/12/2010] [Indexed: 05/29/2023]
Abstract
Aqueous suspensions of single walled carbon nanotubes (SWCNTs) were prepared with the aid of dye molecules to form thermodynamically stable colloidal systems. By adding sodium chloride electrolyte, SWCNTs flocculated and settled out due to the destabilization of colloidal systems initiated by the increase in ionic strength. The dye molecules were removed by heat treatment at 300 degrees C for 5 h following washing with water. Raman spectroscopy was used to monitor the whole procedure. The resulting spectra confirm the non-deconstructive dispersion and flocculation of SWCNTs and the complete removal of the dye molecules; Fourier transform infrared spectroscopy also confirms this.
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Affiliation(s)
- Wei Zhang
- Nanoelectronics Centre, Advanced Technology Institute, University of Surrey, Guildford, Surrey GU2 7XH, UK.
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22
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Kobayashi N, Naya M, Ema M, Endoh S, Maru J, Mizuno K, Nakanishi J. Biological response and morphological assessment of individually dispersed multi-wall carbon nanotubes in the lung after intratracheal instillation in rats. Toxicology 2010; 276:143-53. [PMID: 20696199 DOI: 10.1016/j.tox.2010.07.021] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2010] [Revised: 07/30/2010] [Accepted: 07/30/2010] [Indexed: 12/31/2022]
Abstract
Biological responses of multi-wall carbon nanotubes (MWCNTs) were assessed after a single intratracheal instillation in rats. The diameter and median length of the MWCNTs used in this study were approximately 60 nm and 1.5 μm, respectively. Groups of male Sprague-Dawley rats were intratracheally instilled with 0.04, 0.2, or 1 mg/kg of the individually dispersed MWCNT suspension. After instillation, the bronchoalveolar lavage fluid was assessed for inflammatory cells and markers, and the lung, liver, kidney, spleen, and cerebrum were histopathologically evaluated at 3-day, 1-week, 1-month, 3-month, and 6-month post-exposure. Transient pulmonary inflammatory responses were observed only in the lungs of the group of rats exposed to 1 mg/kg of MWCNTs. Morphology of the instilled MWCNTs in the lungs of rats was assessed using light microscopy and transmission electron microscopy (TEM). Light microscopy examination revealed that MWCNTs deposited in the lungs of the rats were typically phagocytosed by the alveolar macrophages and these macrophages were consequently accumulated in the alveoli until 6-month post-exposure. The 400 TEM images obtained showed that all MWCNTs were located in the alveolar macrophages or macrophages in the interstitial tissues, and MWCNTs were not located in the cells of the interstitial tissues. There was no evidence of chronic inflammation, such as angiogenesis or fibrosis, induced by MWCNT instillation. These results suggest that MWCNTs were being processed and cleared by alveolar macrophages.
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Affiliation(s)
- Norihiro Kobayashi
- Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology, 16-1 Onagawa, Tsukuba, Ibaraki 305-8569, Japan.
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