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Introduction In this invited contribution to the NATAS (North American Thermal Analysis Society) conference proceedings, I am briefly summarizing the projects of my group on single-wall carbon nanotubes (CNTs), conducted at

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Journal of Thermal Analysis and Calorimetry
Authors: F. Xu, L. Sun, J. Zhang, Y. Qi, L. Yang, H. Ru, C. Wang, X. Meng, X. Lan, Q. Jiao, and F. Huang

Abstract  

Heat capacities of the carbon nanotubes (CNTs) with different sizes have been measured by modulated temperature differential scanning calorimetry (MDSC) and reported for the first time. The results indicated the values of C p increased with shortening length of CNTs when the diameters of CNTs were between 60 and 100 nm. However, the values of C p of CNTs were not affected by their diameter when the lengths of CNTs were 1–2 um, or not affected by the length of CNTs when their diameters were below 10 nm. The thermal stabilities of the CNTs have been studied by TG-DTG-DSC. The results of TG-DTG showed that thermal stabilities of CNTs were enhanced with their diameters increase. With lengths increase, the thermal stabilities of CNTs increased when their diameters were between 60 and 100 nm, but there is a slight decrease when their diameters were less than 60 nm. The further DSC analyses showed both released heat and T onset increased with the increase of CNTs diameters, which confirms the consistency of the results from both TG-DTG and DSC on CNTs thermal stability.

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Journal of Thermal Analysis and Calorimetry
Authors: Sangram Samal, Elizabeth Fernandes, Federica Chiellini, and Emo Chiellini

Abstract  

In the present study polymeric membranes consisting of poly(vinyl alcohol) (PVA) and multi-walled carbon nanotubes (MWCNTs) were prepared by casting method and their morphological, thermal and de-swelling behaviour were characterized. The effect of MWCNTs in the hybrid membranes was more significant when its concentration was high. The thermo degradation (T d) and crystallization (T c) temperatures of PVA increased of 10 and 9 °C, respectively in presence of 50 × 10−2 w v−1% of MWCNTs (PVNT3). Besides, the amount of non-free water increases with increasing of MWCNTs probably due to a capillary effect.

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formulations. Carbon nanotubes (CNTs) display exceptional properties that can potentially be used in many applications ranging from macroscopic material composites down to nanodevices. The properties and applications of CNTs and related materials have

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fracture toughness, is trying to be solved by adding carbon nanotubes (CNT). This is expected to improve the mechanical and thermal behaviour of the epoxy resins, increasing also their electrical conductivity [ 1 – 3 ]. However, in the last years, it was

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Introduction Having exceptional blending of essential material properties, CNT either single-walled (SWNT) or multi-walled (MWNT) is presently considered to be the most promising candidate for next generation nanotechnology [ 1

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Acta Chromatographica
Authors: A. Ochoa, J. Fechine, J.C. Escalona, J. García, S.G. dos Santos, and M. Sobral da Silva

Excoecaria lucida Sw. is an evergreen shrub widely distributed in Cuba and throughout the Caribbean region. In spite of its extended traditional use as antiasthmatic and antimicrobial by the local population, scientific reports on the species are almost nonexistent. This paper focuses on the isolation and characterization of compounds present in the crude extract of E. lucida Sw. leaves through the combined use of chromatographic and spectroscopic techniques (medium pressure liquid chromatography, thin-layer chromatography, gas chromatography, nuclear magnetic resonance 1H, and mass spectrometry). A total of 15 nonpolar substances were identified in the four main fractions obtained; some of these substances could be related with the antimicrobial properties attributed to the species.

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Journal of Thermal Analysis and Calorimetry
Authors: Eudes Lorençon, Rodrigo G. Lacerda, Luiz O. Ladeira, Rodrigo R. Resende, André S. Ferlauto, Ulf Schuchardt, and Rochel M. Lago

Introduction Carbon nanotubes (CNTs) have been intensely investigated due to their unique chemical, mechanical, and electrical behavior. The inherent properties of CNTs make them versatile supports for metallic nanoparticles

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Abstract  

Ultrahigh molecular mass polyethylene (UHMMPE) is filled with carbon nano-tubes (CNTs) by solution in the presence of maleic anhydride grafted styrene-(ethylene-co-butylene)-styrene copolymer (MA-SEBS) as a compatibilizer. The UHMMPE/CNT composites crystallized from melt were prepared at a cooling rate of 20C min-1. The melting and crystallization behaviors of UHMMPE/ CNT composites were investigated by differential scanning calorimetry. The results showed that onset melting temperature (T m) and degree of crystallinity (X c) of UHMMPE/CNT composites crystallized from solution are higher than those from melt due to the larger crystalline lamellar thickness. The onset crystallization temperature (T c) of UHMMPE/CNT composites tends to shift to higher temperature region with increasing CNT content in the composites. Tm and Tc of UHMMPE phase in UHMMPE/CNT composites decrease with the addition of MA-SEBS. Moreover, the crystallization rate of UHMMPE phase in UHMMPE/CNT composite is increased due to the introduction of CNTs. MA-SEBS acts as compatilizer, enhances the dispersion of CNTs in the UHMMPE matrix. Thereby, the crystallization rate of UHMMPE phase in UHMMPE/CNT composite is further increased with the addition of MA-SEBS.

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Abstract  

Carbon nanotube field emission display (CNT-FED) represents both emerging application of nanotechnology and revolutionary invention of display. Therefore, it is an important subject to monitor the states and trends of CNT-FED technology before the next stage of development. The present paper uses patent bibliometric analysis and patent network analysis to monitor the technological trends in the field of CNT-FED. These results firstly reveal the different aspects of patenting activities in the field of CNT-FED. Then, patent network analysis indicates the developing tendency of worldwide FED production based on the synthesis of CNT materials. Furthermore, key technologies of three clusters can be identified as the depositing CNT on substrate, coating phosphor on screen and assembling process for whole device. Finally, emitter material is taken for the key factor in R&D work to improve the efficacy in CNT-FED technology.

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