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Littérature scientifique sur le sujet « SWCNH »

Auteur : Grafiati

Publié le 1 avril 2023

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Articles de revues sur le sujet "SWCNH"

Szymański, Grzegorz Stanisław, Anna Kaczmarek-Kędziera, Monika Zięba, Piotr Kowalczyk et Artur Piotr Terzyk. « Insight into the Mechanisms of Low Coverage Adsorption of N-Alcohols on Single Walled Carbon Nanohorn ». Materials 14, n^o 14 (17 juillet 2021) : 4001. http://dx.doi.org/10.3390/ma14144001.

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We report for the first time the chromatographic study of n-alcohols (from methanol to butanol) adsorption on single walled carbon nanohorn (SWCNH). Using measured temperature dependence of adsorption isotherms (373–433 K) the isosteric adsorption enthalpy is calculated and compared with the data reported for a graphite surface. It is concluded that a graphite surface is more homogeneous, and the enthalpy of adsorption on SWCNHs at zero coverage correlates well with molecular diameter and polarizability, suggesting leading role of dispersive interactions, i.e., no heteroatoms presence in the walls of SWCNH structures. Next using modern DFT approach we calculate the energy of n-alcohols interactions with a graphene sheet and with a single nanocone finally proposing a more realistic—double nanocone model. Obtained results suggest alcohols entrapping between SWCNH with OH groups located toward nanocones ends, leading to the conclusions about very promising future applications of SWCNHs in catalytic reactions with participation of n-alcohols.

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Zieba, Wojciech, Piotr Olejnik, Stanislaw Koter, Piotr Kowalczyk, Marta E. Plonska-Brzezinska et Artur P. Terzyk. « Opening the internal structure for transport of ions : improvement of the structural and chemical properties of single-walled carbon nanohorns for supercapacitor electrodes ». RSC Advances 10, n^o 63 (2020) : 38357–68. http://dx.doi.org/10.1039/d0ra07748h.

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Sani, Elisa, Nicolò Papi, Luca Mercatelli et Aldo Dell’Oro. « Efficient Optical Limiting in Carbon-Nanohorn Suspensions ». Energies 14, n^o 8 (8 avril 2021) : 2074. http://dx.doi.org/10.3390/en14082074.

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Nonlinear optical properties of aqueous dispersions of single-wall carbon nanohorns (SWCNH) are investigated by a simple and original technique, relating nonlinear transmittance measurements with semi-empirical model fitting and allowing to identify the dominant nonlinear mechanism. The nanofluids shown a particularly strong optical limiting under irradiation by nanosecond laser pulses at 355, 532 and 1064 nm, much stronger than that previously reported in SWCNHs with smaller aggregate size. The effect is more relevant at 355 nm, where a nearly ideal optical limiting behavior with output energy practically independent on the input one is obtained, and it is attributed to the massive production of bubbles under the effect of light irradiation. This result opens interesting perspectives for the use of SWNCH-based suspensions for smart materials applications and green energy.

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Dong, Jinling, Ying Zhang, Zhihong Xie, Jie He et Tiantian Wu. « SWCNH (Single walled carbon nanohorn) supervises ER (Endoplasmic reticulum) stress through triggering autophagy process of hepatocytes, especially in hepatoma cell line HepG2 ». Materials Research Express 8, n^o 12 (1 décembre 2021) : 125602. http://dx.doi.org/10.1088/2053-1591/ac452b.

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Abstract Backgrounds. The cellular homeostasis is major maintained by the catabolic pathway of autophagy. Our previous work indicated that SWCNH were associated with endoplasmic reticulum (ER) stress mediated by calcium flow and autophagic response. But, its mechanism was unclear. Methods. The regulation of SWCNH on the calcium flow then autophagy of liver cells were investigated through inducing ER stress with tunicamycin and SWCNH. The calcuim flow was determined using Fluo-3, then autophagy was examined with immunofluorescence or western blot for LC3, Beclin-1, ATG-5, and p62. Moreover, the apopototic protein of Bax and Bcl-2 was detected, too. Results. Tunicamycin-induced ER stress in hepatocytes was related to calcium flow, especially for hepatoma cell line HepG2. Moreover, SWCNH participated in the regulation of endoplasmic reticulum stress-related calcium flow. Besides, SWCNH induced hepatocyte autophagy and inhibited cell apoptosis, then mediated the process of hepatocyte autophagy. Conclusions. Tunicamycin-induced ER stress in hepatocytes was related to calcium flow. Moreover, SWCNH induced hepatocyte autophagy, inhibited cell apoptosis, and participated in the autophagy regulation of hepatocyte, especially for hepatoma cell line.

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Bera, Ranadip, Sumanta Kumar Karan, Amit Kumar Das, Sarbaranjan Paria et Bhanu Bhusan Khatua. « Single wall carbon nanohorn (SWCNH)/graphene nanoplate/poly(methyl methacrylate) nanocomposites : a promising material for electromagnetic interference shielding applications ». RSC Advances 5, n^o 86 (2015) : 70482–93. http://dx.doi.org/10.1039/c5ra07718d.

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Single wall carbon nanohorn (SWCNH)/graphene nanoplates (GNP)/poly(methyl methacrylate) (PMMA) nanocomposites were prepared through addition of GNP/PMMA bead into the SWCNH dispersed PMMA matrix during its polymerization.

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Cobianu, Cornel, Bogdan-Catalin Serban, Niculae Dumbravescu, Octavian Buiu, Viorel Avramescu, Cristina Pachiu, Bogdan Bita, Marius Bumbac, Cristina-Mihaela Nicolescu et Cosmin Cobianu. « Organic–Inorganic Ternary Nanohybrids of Single-Walled Carbon Nanohorns for Room Temperature Chemiresistive Ethanol Detection ». Nanomaterials 10, n^o 12 (18 décembre 2020) : 2552. http://dx.doi.org/10.3390/nano10122552.

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Organic–inorganic ternary nanohybrids consisting of oxidized-single walled carbon nanohorns-SnO2-polyvinylpyrrolidone (ox-SWCNH/SnO2/PVP) with stoichiometry 1/1/1 and 2/1/1 and ox-SWCNH/ZnO/PVP = 5/2/1 and 5/3/2 (all mass ratios) were synthesized and characterized as sensing films of chemiresistive test structures for ethanol vapor detection in dry air, in the range from 0 up to 50 mg/L. All the sensing films had an ox-SWCNH concentration in the range of 33.3–62.5 wt%. A comparison between the transfer functions and the response and recovery times of these sensing devices has shown that the structures with ox-SWCNH/SnO2/PVP = 1/1/1 have the highest relative sensitivities of 0.0022 (mg/L)−1, while the devices with ox-SWCNH/SnO2/PVP = 2/1/1 have the lowest response time (15 s) and recovery time (50 s) for a room temperature operation, proving the key role of carbonic material in shaping the static and dynamic performance of the sensor. These response and recovery times are lower than those of “heated” commercial sensors. The sensing mechanism is explained in terms of the overall response of a p-type semiconductor, where ox-SWCNH percolated between electrodes of the sensor, shunting the heterojunctions made between n-type SnO2 or ZnO and p-type ox-SWCNH. The hard–soft acid–base (HSAB) principle supports this mechanism. The low power consumption of these devices, below 2 mW, and the sensing performances at room temperature may open new avenues towards ethanol sensors for passive samplers of environment monitoring, alcohol test portable instruments and wireless network sensors for Internet of Things applications.

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Liu, Zhongyuan, Wei Zhang, Wenjing Qi, Wenyue Gao, Saima Hanif, Muhammad Saqib et Guobao Xu. « Label-free signal-on ATP aptasensor based on the remarkable quenching of tris(2,2′-bipyridine)ruthenium(ii) electrochemiluminescence by single-walled carbon nanohorn ». Chemical Communications 51, n^o 20 (2015) : 4256–58. http://dx.doi.org/10.1039/c5cc00037h.

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The quenching of electrochemiluminescence by SWCNH has been reported for the first time. It enables the development of a sensitive, label-free, and signal-on ATP aptasensor using SWCNH as both quencher and scaffold.

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Kim, Ji Hoon, Seunggun Yu, Sang Won Lee, Seung-Yong Lee, Keun Soo Kim, Yoong Ahm Kim et Cheol-Min Yang. « Enhanced Thermoelectric Properties of WS2/Single-Walled Carbon Nanohorn Nanocomposites ». Crystals 10, n^o 2 (24 février 2020) : 140. http://dx.doi.org/10.3390/cryst10020140.

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Recently, two-dimensional tungsten disulfide (WS2) has attracted attention as a next generation thermoelectric material due to a favorable Seebeck coefficient. However, its thermoelectric efficiency still needs to be improved due to the intrinsically low electrical conductivity of WS2. In the present study, thermoelectric properties of WS2 hybridized with highly conductive single-walled carbon nanohorns (SWCNHs) were investigated. The WS2/SWCNH nanocomposites were fabricated by annealing the mixture of WS2 and SWCNHs using a high-frequency induction heated sintering (HFIHS) system. By adding SWCNHs to WS2, the nanocomposites exhibited increased electrical conductivity and a slightly decreased Seebeck coefficient with the content of SWCNHs. Hence, the maximum power factor of 128.41 μW/mK2 was achieved for WS2/SWCNHs with 0.1 wt.% SWCNHs at 780 K, resulting in a significantly improved thermoelectric figure of merit (zT) value of 0.027 compared to that of pristine WS2 with zT 0.017.

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Roverso, Marco, Roberta Seraglia, Raghav Dogra, Denis Badocco, Silvia Pettenuzzo, Luca Cappellin, Paolo Pastore et Sara Bogialli. « Single-Walled Carbon Nanohorns as Boosting Surface for the Analysis of Low-Molecular-Weight Compounds by SALDI-MS ». International Journal of Molecular Sciences 23, n^o 9 (30 avril 2022) : 5027. http://dx.doi.org/10.3390/ijms23095027.

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Limits of Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry (MS) in the study of small molecules are due to matrix-related interfering species in the low m/z range. Single-walled carbon nanohorns (SWCNH) were here evaluated as a specific surface for the rapid analysis of amino acids and lipids by Surface-Assisted Laser Desorption Ionization (SALDI). The method was optimized for detecting twenty amino acids, mainly present as cationized species, with the [M+K]+ response generally 2-time larger than the [M+Na]+ one. The [M+Na]+/[M+K]+ signals ratio was tentatively correlated with the molecular weight, dipole moment and binding affinity, to describe the amino acids’ coordination ability. The SWCNH-based surface was also tested for analyzing triglycerides in olive oil samples, showing promising results in determining the percentage composition of fatty acids without any sample treatment. Results indicated that SWCNH is a promising substrate for the SALDI-MS analysis of low molecular weight compounds with different polarities, enlarging the analytical platforms for MALDI applications.

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Moreno-Lanceta, Alazne, Mireia Medrano-Bosch et Pedro Melgar-Lesmes. « Single-Walled Carbon Nanohorns as Promising Nanotube-Derived Delivery Systems to Treat Cancer ». Pharmaceutics 12, n^o 9 (7 septembre 2020) : 850. http://dx.doi.org/10.3390/pharmaceutics12090850.

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Cancer has become one of the most prevalent diseases worldwide, with increasing incidence in recent years. Current pharmacological strategies are not tissue-specific therapies, which hampers their efficacy and results in toxicity in healthy organs. Carbon-based nanomaterials have emerged as promising nanoplatforms for the development of targeted delivery systems to treat diseased cells. Single-walled carbon nanohorns (SWCNH) are graphene-based horn-shaped nanostructure aggregates with a multitude of versatile features to be considered as suitable nanosystems for targeted drug delivery. They can be easily synthetized and functionalized to acquire the desired physicochemical characteristics, and no toxicological effects have been reported in vivo followed by their administration. This review focuses on the use of SWCNH as drug delivery systems for cancer therapy. Their main applications include their capacity to act as anticancer agents, their use as drug delivery systems for chemotherapeutics, photothermal and photodynamic therapy, gene therapy, and immunosensing. The structure, synthesis, and covalent and non-covalent functionalization of these nanoparticles is also discussed. Although SWCNH are in early preclinical research yet, these nanotube-derived nanostructures demonstrate an interesting versatility pointing them out as promising forthcoming drug delivery systems to target and treat cancer cells.

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Thèses sur le sujet "SWCNH"

Sharma, Amrit Prasad. « Electronic characterization of swcnt/block copolymer-based nanofiber for biosensor applications ». DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2016. http://digitalcommons.auctr.edu/dissertations/3118.

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The aim of this research is to fabricate an electrically conducting, smooth, continuous and sensitive nanofiber using tri-block copolymer PS-b-PDMS-b-PS and SWCNTs by electrospinning. The electronic nanofibers may be utilized for effective biosensing applications. The SWCNTs have been of great interest to researchers because of their exceptional electrical, mechanical, and thermal properties. The nanoscale diameter, high aspect ratio, and low density make them an ideal reinforcing candidate for novel nanocomposite material. Electrically conducting fibers are prepared by electrospinning a solution of PS, PS-b- PDMS-b-PS and functionalized SWCNTs using solvent DMF. The fibers formed have an average diameter and height of 5 and 4 μm respectively. These fibers are characterized by SEM, AFM, and optical microscopy. The electrical characterization of a single fiber shows an almost linear graph of current vs. voltage using the Kelvin Sensing method. This linear graph exemplifies the conducting nature of the fiber. Future work includes preparing nanofibers decorated with functional groups and binding with specific type of enzyme or protein to study their I-V behavior. This approach or method can be utilized for bio-sensing activities, especially for the detection of various antibodies and protein molecules.

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Adams, Melanie Chantal. « Highly - conductive cathode for lithium-ion battery using M13 phage - SWCNT complex ». Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81137.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 27).
Lithium-ion batteries are commonly used in portable electronics, and the rapid growth of mobile technology calls for an improvement in battery capabilities. Reducing the particle size of electrode materials in synthesis is an important strategy for improving their rate capability and power density (which is the capacity at high rates). Using biological materials as a template during synthesis allows us to achieve this, improving synthesis methods. Utilizing biological materials makes it possible to synthesize nano-scale particles, and using the M13 virus has shown to be an early solution. The addition of conductive material, such as single-walled carbon nanotubes (SWCNT or CNT), also improves the conductivity of the electrode, further improving the battery's rate capabilities (Lee et al., 2009). In this study, our goal is to improve the conductivity of the LIB battery cathode using M13-carbon nanotube complexes.
by Melanie Chantal Adams.
S.B.

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Müller, Christian, Ammar Al-Hamry, Olfa Kanoun, Mahfujur Rahaman, Dietrich R. T. Zahn, Elaine Yoshiko Matsubara et José Mauricio Rosolen. « Humidity Sensing Behavior of Endohedral Li-Doped and Undoped SWCNT/SDBS Composite Films ». MDPI AG, 2019. https://monarch.qucosa.de/id/qucosa%3A33173.

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We have investigated single-walled carbon nanotube (SWCNT) networks wrapped with the cationic surfactant sodium dodecyl-benzenesulfonate (SBDS) as promising candidates for water detection. This is the first time that the humidity behavior of endohedral Li-doped (Li@) and undoped SWCNTs/SDBS has been shown. We identified a strong and almost monotonic decrease in resistance as humidity increased from 11 to 97%. Sensitivities varied between −3 and 65% in the entire humidity range. Electrical characterization, Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM) analysis revealed that a combination of the electron donor behavior of the water molecules with Poole-Frenkel conduction accounted for the resistive humidity response in the Li@SWCNT/SDBS and undoped SWCNT/SDBS networks. We found that Li@SWCNTs boosted the semiconducting character in mixtures of metallic/semiconducting SWCNT beams. Moreover, electrical characterization of the sensor suggested that endohedral Li doping produced SWCNT beams with high concentration of semiconducting tubes. We also investigated how frequency influenced film humidity sensing behavior and how this behavior of SWCNT/SDBS films depended on temperature from 20 to 80 ∘ C. The present results will certainly aid design and optimization of SWCNT films with different dopants for humidity or gas sensing in general.

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Gupta, Ankit. « Multi-Scale Modeling of Mechanical Properties of Single Wall Carbon Nanotube (SWCNT) Networks ». Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1022.

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Single wall carbon nanotubes (SWCNTs) show a variety of unparalleled properties such as high electrical and thermal conductivity, high specific surface area (SSA) and a large stiffness under axial loads. One of the major challenges in tapping the vast potential of SWCNTs is to fabricate nanotube based macrostructures that retain the unique properties of nanotubes. Pristine SWCNT aerogels are highly porous, isotropic structures of nanotubes mediated via van der Waals (VDW) interactions at junctions. The mechanical behavior of such aerogels is examined in several experimental studies. However, it is necessary to supplement these studies with insights from simulations in order to develop a fundamental understanding of deformation behavior of SWCNT aerogels. In this study, the mechanical behavior of SWCNT networks is studied using a multi-scale modeling approach. The mechanics of an individual nanotube and interactions between few nanotubes are modeled using molecular dynamics (MD) simulations. The results from atomistic simulations are used to inform meso-scale and continuum scale finite element (FE) models. The deformation mechanism of pristine SWCNT networks under large compressive strain is deduced from insights offered by meso-scale simulations. It is found that the elasticity of such networks is governed by the bending deformation of nanotubes while the plastic deformation is governed by the VDW interactions between nanotubes. The stress response of the material in the elastic regime is dictated by the VDW stresses on nanotubes while in the plastic regime, both the VDW and axial deformation stresses on nanotubes drive the overall stress response. In this study, the elastic behavior of a random SWCNT network with any set of junction stiffness and network density is also investigated using FE simulations. It is found that the elastic deformation of such networks can be governed either by the deformation of the nanotubes (bending, axial compression) or deformation of the junctions. The junction stiffness and the network density determine the network deformation mode. The results of the FE study are also applicable to any stiff fiber network.

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Miller, Matthew Ryan. « Mechanical Properties of PLGA Polymer Composites Using Nonfunctionalized Carbon Nanotubes as Reinforcement ». OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1203.

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Poly[lactic co-glycolic] acid (PLGA) is a biocompatible polymer commonly used in the field of tissue engineering, but its mechanical properties tend to be less than ideal for most orthopedic applications. Five PLGA composites, reinforced with 0 to 1% nonfunctionalized single-walled carbon nanotubes, were prepared and tested for tensile strength. In order to achieve consistent nanotube dispersions, sodium dodecyl sulfate was incorporated as a surfactant. The polymer scaffold fabrication methods were successful at creating suitable samples for tensile testing. After the tests were performed, scanning electron microscope images were taken to examine the fractured edges and determine the cause of failure. Analysis of fractured surfaces indicated good nanotube dispersions in all composite samples, and an increase in tensile strength, with respect to the control (0.532 MPa), was found for composites at the 0.07% nanotube and 0.09% nanotube concentrations (0.570 MPa and 0.643 MPa respectively). Total length at failure decreased as carbon nanotube concentration increased. This experiment showed a promising trend toward increasing the mechanical properties of PLGA/carbon nanotube composites and represented a prospective foundation for future research.

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Chan, Ka Keung. « SYNTHESIS AND FUNCTIONALITY STUDY OF NOVEL BIOMIMETIC N-GLYCAN POLYMERS ». Cleveland State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=csu162309270958734.

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Mada, Mykanth Reddy Materials Science &amp Engineering Faculty of Science UNSW. « Fabrication and characterisation of SWCNT-PMMA and charcoal-PMMA composites with superior electrical conductivity and surface hardness properties ». Awarded by:University of New South Wales. Materials Science & ; Engineering, 2009. http://handle.unsw.edu.au/1959.4/41831.

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Fabrication of SWCNT-PMMA and Activated Charcoal- PMMA composites was carried out by the compression moulding technique. Then Mechanical and Electrical properties of the composites were investigated. The morphological studies of composites showed a) good dispersion of fillers and b) good interaction between fillers and matrix. Electrical conductivity of SWCNT-PMMA composites was increased by 9 orders of magnitude (at 0.8 % volume fraction of SWCNT) and that of AC-PMMA composites increased by 16 orders of magnitude (at 17 % volume fraction of AC). The percolation threshold of both composites turned out to be lower compared to the theoretical values. A significant improvement in mechanical properties was obtained ??? particularly in AC-PMMA composites which showed a 400 % improvement in Vickers microhardness ??? raising the polymer matrix abrasion property literally to that of Aluminium alloys (Dobrazanski et al 2006). In conclusion, it is to be noted that Activated Charcoal - PMMA composites have a great potential for cost effective conducting polymer composite production by the use of cheap filler: In addition, the compression moulding technique shows good potential for cost effective fabricating technique for amorphous polymers with high electrical and mechanical properties.

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Porto, Arthur Barra. « Oxidação controlada e funcionalização de nanotubos de carbono de parede única : uma abordagem experimental e teórica ». Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/4817.

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O tratamento químico de nanotubos de carbono (NTC) é necessário para aprimorar suas propriedades, aplicações e remover impurezas. O tratamento, com ácidos fortes como H2SO4 e HNO3 tem sido a alternativa mais utilizada. A mistura desses ácidos fortes produz espécies eletrofílica NO2+, íon nitrônio, que é um potencial agente oxidante, cuja concentração depende da proporção da mistura H2SO4:HNO3. Neste trabalho, a interação entre o íon nitrônio e o nanotubo de carbono de camada única (SWCNT, do inglês Single-Walled Carbon Nanotube) foi explorado experimental e computacionalmente. Experimentalmente a solução H2SO4:HNO3 foi analisada em proporções diferentes (1:1, 2:1, 5:2, 3:1, 4:1, 5:1, 6:1, 7:1 e 8:1 v/v) e a concentração de íon nitrônio foi obtida utilizando-se uma curva analítica construída com uma solução padrão de NO2BF4 em H2SO4. Todas as espécies na mistura ácida foram caracterizadas por espectroscopia Raman. Os resultados mostraram que a concentração do íon nitrônio na mistura ácida varia de 0 até 4,53 mol/L. As misturas 2:1, 5:2 e 3:1 foram então utilizadas para a oxidação química de SWCNT por 4, 8 e 12 horas. As amostras finais foram analisadas por espectroscopia Raman, análise termogravimétrica (TG) e espectroscopia de raios X por dispersão de energia (EDS). Dentre os resultados, foram observados por meio da espectroscopia Raman uma alta desordem estrutural no sistema após a oxidação, com significativas mudanças nos modos de respiração radial (RBM), como o desaparecimento de bandas de tubos com pequenos diâmetros, além do aumento dada razão ID/IG de 0,027 para 0,59 em tubos oxidados com a mistura 3:1. As análises TG mostraram um aumento na temperatura de decomposição dos tubos em, pelo menos, 30ºC se comparado às amostras padrão, sugerindo um significativo grau de oxidação. Os resultados de EDS apontaram um aumento considerável na quantidade de oxigênio, passando de 7% para 20%, aumentando com o aumento do tempo de reação e com a concentração do íon nitrônio. Computacionalmente a interação entre o íon nitrônio e o SWCNT foi estudada através de cálculos de mecânica quântica. Foram analisados modelos do tipo armchair (5,5), sendo um tubo perfeito (P) e dois outros contendo defeitos do tipo Stone-Wales (SW) e monovacância (V1) para modelar regiões distintas na superfície do nanotubo. Para os modelos P e SW, o grupo funcional éter (COC) foi obtido como um produto principal, com um epóxido (CCO) encontrado como um intermediário de reação. As barreiras de energia livre de Gibbs foram de 31,7 kcal.mol-1 (P) e 37,8 kcal.mol-1 (SW) em solução aquosa à 298,15 K e 1 atm. O mecanismo envolvendo o modelo V leva à obtenção de uma carbonila (CO) como produto principal, formado espontaneamente através da adsorção do íon NO2+. O mecanismo de alta energia também foi descrito no modelo V, passando por um estado de transição, caracterizado como um anel do tipo oxaziridina. Através deste caminho um grupamento do tipo alcóxido (CO-) é formado inicialmente e reage com um carbono vizinho, produzindo um grupo funcional do tipo éter (COC). A energia livre de Gibbs de ativação foi de 4,5 e 11,2 kcal.mol-1 para primeiro (CO-) e segundo (COC) passos, respectivamente. Os resultados reportados sugerem o início da oxidação em meio ácido através da região de vacância, com primeira oxidação levando a uma carbonila, seguida das reações nos defeitos topológicos (P e SW) na superfície com a formação de um éter (COC) como principal produto.
The chemical treatment of carbon nanotubes (CNT) is necessary to improve their properties, applications and to remove impurities. Treatments with strong acids as H2SO4 and HNO3 is the mostly used alternative. The mixture of these strong acids produces the electrophilic species NO2+, the nitronium ion that is a potential oxidizing with concentration depending on the H2SO4:HNO3 proportion. In this work the interaction between the nitronium ion and a single-walled carbon nanotube (SWCNT) was explored experimentally e theoretically. Experimentally, the H2SO4:HNO3 solution was analyzed at different proportions (1:1, 2:1, 5:2, 3:1, 4:1, 5:1, 6:1, 7:1 and 8:1 v/v) and the nitronium ion concentration obtained using a calibration plot constructed from a standard solution of NO2BF4 in H2SO4. All the species in the acid mixture were characterized by Raman spectroscopy. The results showed that the concentration of nitronium ion in the acid mixtures varied from 0 to 4.53 mol/L. The mixtures 2:1, 5:2 and 3:1 were then used for the chemical oxidation of single-walled CNT for 4, 8 and 12 hours. The final samples were analyzed by Raman spectroscopy, thermal gravimetric analysis (TGA) and energy dispersive X-ray spectroscopy (EDS). It was observed by Raman spectroscopy a higher structural disorder in the system after the oxidation, with significant changes in RBM modes, such as disappearance of bands of small diameter tubes, and in the ID/IG ratio, which increases from 0.027 until 0.59 to CNT oxidized with 3:1 mixture. The TGA showed an increase in the temperature of the tube decomposition of at least 30ºC relative to the pristine form, suggesting a significant oxidation degree. The EDS data point to considerable increase of the oxygen amount from 7% to at least 20%, increasing with the reaction time and nitronium ion concentration. Theoretically the interaction between nitronium ion and SWCNT was studied by quantum mechanical calculations. In addition to the pristine (P) form of an armchair (5,5) SWCNT, two other species containing Stone-Wales (SW) and mono-vacancy (V1) defects were considered in order to model the distinct defective regions on the carbon nanotube surface. For the P and SW regions, the ether (COC) functional group was predicted as the main product, with an epoxide (CCO) found as a reactive intermediate. The Gibbs free energy barriers were predicted to be 31.7 (P) and 37.8 kcal mol-1 (SW) in aqueous solution at 298.15 K and 1 atm. The mechanism involving the V1 region leads to the carbonyl group (CO) as the main product, which is formed spontaneously upon NO2+ adsorption without energy barrier. A higher energy mechanism was also described for V1 region, passing through a transition state characterized as an oxaziridine-like ring. Through this pathway an alkoxy (CO-) is firstly formed and reacts with the neighbor carbon yielding the ether (COC) functional group. The activation Gibbs free energies were 4.5 and 11.2 kcal mol-1 for the first (CO- formation) and second (COC formation) steps, respectively. The results reported here suggest that at the beginning of oxidation in acid medium, the vacancy regions (V) are firstly oxidized leading to the carbonyl (CO) functional groups, followed by reactions at the topological defective parts (P and SW) of the tube surface where the ether (COC) function is the main product.

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Kraft, Thomas. « Ternary blend ink formulations for fabricating organic solar cells via inkjet printing ». Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0027.

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L’objectif final de la thèse est l'impression de la couche photo-active ternaire d'une cellule solaire organique en utilisant deux approches: l'une concerne l'apport de nanotubes de carbone (SWCNT) pour améliorer les propriétés de transport, l'autre concerne la préparation de mélanges ternaires de matériaux pour contrôler la couleur des cellules. Les encres pour la couche active incluant des SWCNT fonctionnalisés sont composées d’un donneur d'électron (polymère) (poly(3-hexylthiophène), [P3HT]) et d’un accepteur d'électron ( [6,6]-phényl C61-butyrique ester méthylique d'acide [PCBM]) et ont été développées pour la fabrication de cellules inversées. Ces cellules sont réalisées sur substrats de verre pour l'optimisation de leurs performances, puis sur substrats plastiques pour les applications. Diverses couches d'interfaces ont été testées, qui incluent l'oxyde de zinc (ZnO, couches obtenues par pulvérisation ionique (IBS) ou à partir de solutions de nanoparticules) pour la couche de transport d'électrons et le PEDOT:PSS, le P3MEET, le V2O5 et le MoO3 pour la couche de transport de trous. Des essais ont été effectués avec et sans CNT afin d’étudier leur impact sur les performances. Des résultats similaires sont obtenus dans les deux cas. Il était attendu que les CNT améliorent les performances, ce qui n’a pas été observé pour le moment. Des travaux supplémentaires sont donc nécessaires au niveau de la formulation de la couche active.Avec trois polymères de couleur rouge (P3HT), bleu (B1) et vert (G1), nous avons préparé des mélanges ternaires efficaces permettant l'obtention de couleurs jusque là indisponibles . Nous avons fait une étude sur le piégeage et les mécanismes de diodes parallèles associés aux mélanges. En général, nous avons constaté que les mélanges ternaires de polymères bleu et vert peuvent être décrits par une mécanisme de diodes parallèles, sans entrainer de perte de performances, ce qui n'est pas possible pour les systèmes P3HT:B1 :PCBM et P3HT:G1:PCBM qui se piègent mutuellement. L’objectif final du projet est l'impression de la couche photo-active ternaire d'une cellule solaire organique, composites ternaires (polymère:polymères:acceptor) ou dopés avec les SWCNT. Cette étape nécessite encore des développements futurs
Two approaches were followed to achieve increased control over properties of the photo-active layer (PAL) in solution processed polymer solar cells. This was accomplished by either (1) the addition of functionalized single-walled carbon nanotubes (SWCNTs) to improve the charge transport properties of the device or (2) the realization of dual donor polymer ternary blends to achieve colour-tuned devices.In the first component of the study, P3HT:PC61BM blends were doped with SWCNTs with the ambition to improve the morphology and charge transport within the PAL. The SWCNTs were functionalized with alkyl chains to increase their dispersive properties in solution, increase their interaction with the P3HT polymer matrix, and to disrupt the metallic characteristic of the tubes, which ensures that the incorporated SWCNTs are primarily semi-conducting. P3HT:PCBM:CNT composite films were characterized and prepared for use as the photoactive layer within the inverted solar cell. The CNT doping acts to increase order within the active layer and improve the active layer’s charge transport properties (conductivity) as well as showed some promise to increase the stability of the device. The goal is that improved charge transport will allow high level PSC performance as the active layer thickness and area is increased, which is an important consideration for large-area inkjet printing. The use of ternary blends (two donor polymers with a fullerene acceptor) in bulk-heterojunction (BHJ) photovoltaic devices was investigated as a future means to colour-tune ink-jet printed PSCs. The study involved the blending of two of the three chosen donor polymers [red (P3HT), blue (B1), and green (G1)] with PC61BM. Through EQE measurements, it was shown that even devices with blends exhibiting poor efficiencies, caused by traps, both polymers contributed to the PV effect. However, traps were avoided to create a parallel-like BHJ when two polymers were chosen with suitable physical compatibility (harmonious solid state mixing), and appropriate HOMO-HOMO energy band alignment. The parallel diode model was used to describe the PV circuit of devices with the B1:G1:PC61BM ternary blend

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Yaya, Abu. « Interactions faibles dans les nanosystèmes carbones ». Nantes, 2011. http://archive.bu.univ-nantes.fr/pollux/show.action?id=f1e38479-78b7-4d42-9bed-71420c161382.

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Avec le logiciel AIMPRO, qui fournit une modélisation quantique basée sur la théorie de fonctionnelle de densité, on étudie plusieurs exemples importants de la faiblesse des interactions intermoléculaires dans les nanomatériaux de carbone. Au niveau mécanique quantique, nos calculs donnent une compréhension fiable et améliorée du rôle et de la fonction des interactions intermoléculaires faibles, ce qui ne peut pas être prédit par des méthodes conventionnelles comme les potentiels interatomiques classiques. Premièrement, on étudie l’interaction entre le brome physisorbé sur les nanomatériaux de carbone (graphène, graphite, nanotubes de carbone simple [SWCNT] et double [DWCNT] parois). Pour le graphène, nous trouvons une nouvelle forme de Br2, à notre connaissance jamais présentée dans la littérature, où la molécule se trouve perpendiculaire à la feuille de graphène avec un dipôle fort. La bromation ouvre un gap de petite taille (86 meV) dans la structuré de bande électronique et dope fortement le graphène. Dans le graphite, Br2 reste parallèle aux couches de carbone avec un transfert de charge moins fort et sans dipôle moléculaire. À plus haute concentration, la formation de chaînes de polybromure est thermodynamiquement favorisée, mais n’a pas lieu spontanément à cause d’une barrière d’activation appréciable (27,01 kJ / mol). Avec les nanotubes monoparoi, le Br2 reste perpendiculaire à la surface du tube, comme observé avec le graphène; dans les fagots, le Br2 s'intercale comme dans le graphite. Les spectres Raman sont enregistrés afin de vérifier ce résultat. Dans la deuxième partie, on étudie des interactions d’empilement de type π-π entre le benzène d’une part, les chaînes oligomères de PPV d’autre part, avec des nanomatériaux de carbone. Pour le dimère du benzène, nous avons réussi à reproduire les structures stables trouvées par ailleurs via des calculs de plus haut niveau de théorie ; pour le benzène sur le graphène ou sur les SWCNTs, l'empilement est de type AB comme dans le graphite. L'orientation de l’interaction dans le cas PPV / PPV est différente de celle obtenue dans le cas PPV / nanotube ou PPV / graphène. Dans le premier cas des plans moléculaires sont orthogonaux, semblable à un empilement de PPV ou d'autres hydrocarbures aromatiques polycycliques. Dans les autres cas, l’axe de la chaîne de PPV se trouve parallèle au plan du graphène comme à l’axe des nanotubes, ce qui est attribué à des effets d'empilement π-π. L'analyse des fonctions d’onde près du niveau de Fermi suggère qu’il y a peu de couplage électronique entre PPV et SWCNTs. La différence d’interaction prévue entre PPV et nanotubes semi-conducteurs ou métalliques suggère une nouvelle conception de composites PPV-SWCNT pour les dispositifs électroluminescents organiques
This thesis uses the ab initio density functional modeling programme AIMPRO to study several important examples of weak intermolecular interactions in carbon nanomaterials. At the quantum mechanical level, our calculations give a reliable and improved understanding of the role and feature of weak intermolecular interactions, which cannot be accurately predicted by conventional methods such as classical interatomic potentials. First, the geometry and binding of bromine physisorbed on carbon nanomaterials (graphene, graphite and single walled nanotubes) is studied. In graphene, we find a new Br2 form which is reported for the first time in this thesis, where the molecule sits perpendicular to the graphene sheet with an extremely strong molecular dipole. Bromination opens a small (86- meV) band gap and strongly dopes the graphene. In graphite Br2 is stable parallel to the carbon layers with less charge transfer and no molecular dipole. At higher Br2 concentrations polybromide chain structures are thermodynamically favoured, but will not occur spontaneously due to an appreciable formation barrier (27. 01 kJ/mol). For single walled nanotubes Br2 lies perpendicular to the tube surface similar to graphene, while in bundles Br2 intercalates similar to graphite. Experimental Raman spectra are recorded to verify this result. We next study π-π stacking interactions between benzene and PPV oligomer chains with various carbon nanomaterials. For the benzene dimer we successfully reproduce high level theory stable structures, and for benzene on graphene and SWCNTs, the stacking arrangement matches AB- stacking in graphite. The orientation of the interaction between PPV/PPV is different from PPV/nanotube or PPV/graphene. In the former the molecular planes are orthogonal, similar to the crystal packing in PPV, as well as in other polyaromatic hydrocarbons. In the others the PPV plane lies (axially) parallel to the substrates, attributed to π-π stacking effects. Wavefunction analysis suggests very little electronic coupling between the PPV and SWCNTs near to the Fermi level. Predicted differences in interaction between PPV and semi-conducting or metallic tubes suggest a new route to experimental ultraefficient composite PPV-SWCNT organic light emitting device design

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Livres sur le sujet "SWCNH"

Graupner, R., et F. Hauke. Functionalization of single-walled carbon nanotubes : Chemistry and characterization. Sous la direction de A. V. Narlikar et Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533046.013.16.

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This article examines the chemical functionalization and structural alteration of single-walled carbon nanotubes (SWCNTs). It describes the covalent functionalization of the SWCNT framework that is the covalent attachment of functional entities onto the CNT scaffold. In particular, it considers the chemical modification and reactivity of SWCNTs in the context of the reactivity of graphite and fullerenes. It also discusses the defect and sidewall functionalization of SWCNTs, along with various techniques used in the characterization ofSWCNTs upon functionalization, namely: thermogravimetric analysis, spectroscopic techniques such as UV-Vis-NIR spectroscopy and Raman spectroscopy, and microscopic techniques like transmission electron microscopy, atomic force microscopy and scanning tunnelling microscopy.

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Chapitres de livres sur le sujet "SWCNH"

Bala Sekhar, D., William R. Taube et A. Kumar. « Electrical Characteristics of SWCNT Chemiresistor ». Dans Physics of Semiconductor Devices, 569–71. Cham : Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-03002-9_143.

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Jani, Umang B., Bhavik A. Ardeshana, Ajay M. Patel et Anand Y. Joshi. « Evaluating the Mass Sensing Characteristics of SWCNC ». Dans Mechatronic Systems Design and Solid Materials, 79–97. First edition. : Apple Academic Press, 2021. http://dx.doi.org/10.1201/9781003045748-4.

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Bianchi, Michele. « Control of Neural Cell Adhesion on 3D-SWCNT ». Dans Multiscale Fabrication of Functional Materials for Regenerative Medicine, 59–71. Berlin, Heidelberg : Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-22881-0_5.

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Hara, Hironori, Yoshio Kato, Genki Ichinose et Stephan Irle. « QM/MD Simulations of High-Temperature SWCNT Self-capping ». Dans Quantum Simulations of Materials and Biological Systems, 53–68. Dordrecht : Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-4948-1_4.

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Thatoi, D. N., S. Choudhury, S. S. Mohapatra et M. K. Nayak. « MHD Up/Down Flow of Nanofluids with SWCNT/MWCNT Suspensions ». Dans Lecture Notes in Mechanical Engineering, 331–39. Singapore : Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-9057-0_35.

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Gutsev, G. L., M. D. Mochena et C. W. Bauschlicher. « All-Electron DFT Modeling of SWCNT Growth Initiation by Iron Catalyst ». Dans Computational Science – ICCS 2006, 128–35. Berlin, Heidelberg : Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/11758532_19.

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Makar, Jon. « The Effect of SWCNT and Other Nanomaterials on Cement Hydration and Reinforcement ». Dans Nanotechnology in Civil Infrastructure, 103–30. Berlin, Heidelberg : Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-16657-0_4.

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Sulochana, V., Sunil Agrawal et Balwinder Singh. « Impact on Performance of Bundled SWCNT Interconnects Surrounded with Semiconductor Shielding Materials ». Dans Lecture Notes in Electrical Engineering, 837–49. Singapore : Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-6772-4_72.

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Nelson, Donna J., Christopher N. Brammer, Panneer Selvam Nagarajan et Paramasivan T. Perumal. « Association of Representative Amides and Aminoalcohols with SWCNT As Revealed by1H NMR ». Dans ACS Symposium Series, 31–51. Washington, DC : American Chemical Society, 2011. http://dx.doi.org/10.1021/bk-2011-1064.ch003.

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Ito, Osamu, et Francis D’Souza. « Functionalized Nanocarbons for Artificial Photosynthesis : From Fullerene to SWCNT, Carbon Nanohorn, and Graphene ». Dans From Molecules to Materials, 193–240. Cham : Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-13800-8_8.

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Actes de conférences sur le sujet "SWCNH"

Cobianu, Cornel, Bogdan-Catalin Serban, Niculae Dumbravescu, Octavian Buiu, Viorel Avramescu, Marius Bumbac, Cristina-Mihaela Nicolescu et Cosmin Cobianu. « Room Temperature Chemiresistive Ethanol Detection by Ternary Nanocomposites of Oxidized Single Wall Carbon Nanohorn (ox-SWCNH) ». Dans 2020 International Semiconductor Conference (CAS). IEEE, 2020. http://dx.doi.org/10.1109/cas50358.2020.9268046.

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Liao, Hengyou, Fulong Zhu et Sheng Liu. « Mechanical stretching behavior simulation of SWCNT and SWCNT-Ni ». Dans 2011 International Symposium on Advanced Packaging Materials (APM). IEEE, 2011. http://dx.doi.org/10.1109/isapm.2011.6105677.

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Qiu, Bo, Yan Wang, Qing Zhao et Xiulin Ruan. « The Effects of Diameter and Chirality in the Thermal Transport in Free-Standing and Supported Carbon-Nanotubes ». Dans ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/mnhmt2012-75323.

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We use molecular dynamics (MD) simulations to explore the lattice thermal transport in freestanding and supported single-wall carbon-nanotube (SWCNT) in comparison to that in graphene nanoribbon (GNR) and graphene sheet. We find the lattice thermal conductivity of freestanding SWCNT and GNR increases with diameter/width and approaches that of graphene. This is partly attributed to the curvature that shortens phonon lifetime in SWCNT. In contrast to GNR, there is only weak chirality dependence in the thermal conductivity of freestanding SWCNT. When SWCNT is put on substrate, an effective boundary along the SWCNT axial direction at the SWCNT-substrate interface is created, rendering resemblance between the phonon transport in supported SWCNT and that in freestanding GNR. As a result, the thermal conductivity of supported SWCNTs differ by around 10%, depending on chirality. The thermal conductivity of SWCNT decreases by about 34–41% when supported, which is less than that of the reduction seen in supported graphene.

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Ito, Kyohei, Shuhei Inoue et Yukihiko Matsumura. « Synthesis of Single-Walled Carbon Nanotube Containing Platinum Group Element ». Dans ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44257.

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To prepare homogeneous nanoparticles is a key issue for catalytic reaction because it directly connects to the control of the reaction. Using the sidewall of SWCNT as a catalyst supporter, the size of nanoparticle can be controlled, because the particle size should be affected by the interaction between SWCNT and metal species and its curvature. In this study, we focused on the direct synthesis of SWCNT with highly dispersed platinum group metal species. As a result, adding an adequate amount of platinum group metals into catalysts never disturbs the synthesis of SWCNT. Referring to TGA measurement, the presence of metal attached and/or metal involved SWCNT is suggested. Furthermore, SEM images show many nanoparticles are on SWCNT. When ruthenium catalyst is used, ruthenium nanoparticles are observed on the surface of nano carbon materials, which looks like SWCNT. These results indicate the possibility of direct synthesis of metal-containing SWCNT in CVD technique.

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Zhang, Kejia, Abhishek Yadav, Kyu Hun Kim, Youngseok Oh, Mohammad F. Islam, Ctirad Uher et Kevin P. Pipe. « Temperature-Dependent Thermal and Thermoelectric Properties of Single-Walled Carbon Nanotube Aerogels ». Dans ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/mnhmt2012-75110.

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Aerogels are ultraporous solids that have found a number of uses due to their very low density. Recently, aerogels based on single-walled carbon nanotubes (SWCNTs) have been fabricated and show significant potential for battery, supercapacitor, sensor, and thermal applications due to the electrical, mechanical, and thermal properties of SWCNTs as well as their capacity for functionalization. In this work we report temperature-dependent (100–300 K) measurements of thermal conductivity, electrical conductivity, and Seebeck coefficient for SWCNT aerogels synthesized through a critical point drying technique. Two types of aerogels are considered: an as-grown SWCNT aerogel and one that is coated with multiple graphitic layers (Gr-SWCNT) leading to significantly improved mechanical properties. Thermal conductivity and electrical conductivity were found to be significantly higher for SWCNT aerogels than for other aerogels, even though they have a much smaller density. Gr-SWCNT aerogels were found to have lower thermal conductivities than as-grown samples.

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Tey, J. N., S. Gandhi, I. P. M. Wijaya, J. Wei, C. R. Suri, I. Rodriguez et S. G. Mhaisalkar. « Liquid Gated Carbon Nanotubes Field Effect Transistors (LG-CNTFET) Platform for Herbicide Sensing ». Dans ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-10571.

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Single-walled carbon nanotube (SWCNT) is a one-dimensional system with all its carbon atoms present on the surface, hence its conductance is highly sensitive to the surrounding charge environment. Due to the extreme charge sensitivity, biocompatibility and chemical stability, SWCNT is particularly interested in biosensing application. In this paper, we demonstrated a practical approach of fabricating laminated SWCNT liquid gate field effect transistor (LGFET) through a solution processed route involving only two materials, PDMS and SWCNT. The laminated SWCNT LGFETs show great potential towards atrazine detection. The change in the detection signal in terms of conductance was deduced to be due to electrostatic gating mechanism caused by the localized interaction between CNT and the biomolecules. Although relatively high concentration was used in the experiment, the detection limit could be lowered down further by improving the signal-to-noise ratio of the measurement, which can be done through either signal amplification, and/or noise reduction.

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Salah, Khaled. « Characterization of SWCNT-based TSV ». Dans 2014 16th International Power Electronics and Motion Control Conference (PEMC). IEEE, 2014. http://dx.doi.org/10.1109/epepemc.2014.6980577.

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Schiffres, Scott N., Kyu Hun Kim, Youngseok Oh, Mohammad F. Islam et Jonathan A. Malen. « Thermal Conductivity of Carbon Nanotube Aerogels With Different Filling Gases ». Dans ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/mnhmt2012-75122.

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We report on measurements of thermal conductivity in single-walled carbon nanotube (SWCNT) aerogels in vacuum, and as infiltrated by different gases. The remarkable thermal, mechanical and electrical properties of single CNTs have led to great interest in bulk carbon nanotube materials, including the CNT aerogels. Carbon nanotube aerogels are light-weight (7–8kg/m3) and porous, which means that heat will be conducted in parallel through the SWCNT matrix and the filling gas. The overall thermal conductivity of the aerogel was measured with helium, and argon filling gases, using a modified 3ω method designed to interrogate low thermal effusivity materials. Measurements of thermal conductivity at vacuum are 0.023 W/m-K and at atmospheric pressure infiltrated SWCNT aerogels have thermal conductivities in helium of 0.19 W/m-K and in argon of 0.039 W/m-K. Our vacuum measurement suggests that transport within the aerogel is limited by the thermal interface resistance between SWCNTs, rather than by phonon transport within the SWCNT itself. We have also extracted the mean distance traveled by gas molecules between collisions with SWCNT aerogel by fitting the gas contribution to thermal conductivity using a kinetic theory based model.

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Gutierrez, Miguel A., Michael Gydesen, Caitlin Marcellus, Ivan Puchades, Brian Landi et Patricia Iglesias. « Effect of Carbon Nanotube-Phosphinate Ionic Liquid Thin Boundary Layer on the Tribological Behavior of Aluminum Alloy in Steel-on-Aluminum Contact ». Dans ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86875.

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In this study, the tribological behavior of the Trihexyl tetradecylphosphonium-bis(2,4,4-trimethylpentyl)phosphinate [THTDP][Phos] ionic liquid with and without single-wall carbon nanotubes (SWCNT) dispersion as a thin boundary layer was intended for investigation. However, the surface heat treatment process was not sufficient to form a thin film on the sample surfaces. Thus, in each test condition, the lubricating agents were used as external (liquid) lubricants. Specifically, [THTDP][Phos] and ([THTDP][Phos]+0.1 wt.% SWCNT) boundary film layers were applied on 6061-T6 aluminum alloy disk samples and tested under sliding contact with 1.5 mm diameter 420C stainless steel balls using a ball-on-flat linearly reciprocating tribometer. A commercially available Mobil Super 10W-40 engine oil (MS10W40) was also tested and used as this investigation’s datum. The tribological behavior of [THTDP][Phos] and ([THTDP][Phos]+SWCNT) boundary film layers was analyzed via wear volume calculations from optical microscopy measurements, as well as by observation of the transient coefficient of friction (COF) obtained through strain gauge measurements made directly from the reciprocating member of the tribometer. Results indicate the potential for reduction of wear volume and coefficient of friction in the IL lubricated steel-on-aluminum sliding contact through (SWCNT) dispersion in the ionic liquid. Wear results are based on measurements obtained using optical microscopy (OM). Results discussed display improved tribological performance for both [THTDP][Phos] and ([THTDP][Phos]+SWCNT) over baseline MS10W40 oil lubricant for both roughness values tested for the steel-on-aluminum contact. No measurable improvements were observed between [THTDP][Phos] and ([THTDP][Phos]+SWCNT) tests.

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Javvaji, Brahmanandam, D. Roy Mahapatra et S. Raha. « Electromagnetic characteristics of Polyaniline/SWCNT composites ». Dans SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, sous la direction de Vijay K. Varadan. SPIE, 2013. http://dx.doi.org/10.1117/12.2010516.

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Rapports d'organisations sur le sujet "SWCNH"

Ervin, Matthew H., Benjamin S. Miller et Brendan Hanrahan. SWCNT Supercapacitor Electrode Fabrication Methods. Fort Belvoir, VA : Defense Technical Information Center, février 2011. http://dx.doi.org/10.21236/ada538479.

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Liu, Tao. Ultrathin SWCNT Films Enabled Multi-modal Fiber Sensors. Fort Belvoir, VA : Defense Technical Information Center, septembre 2014. http://dx.doi.org/10.21236/ada610296.

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