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Abstract  

The study was undertaken to evaluate the feasibility of functionalized multi-walled carbon nanotubes (MWCNTs) for the removal of UO2 2+ from aqueous solutions. The MWCNTs was treated by oxygen plasma and characterized by FTIR and XPS. The characterization indicates that MWCNTs is successfully functionalized of oxygen groups such as –COOH on its surface (denote as P-MWCNTs). The sorption of UO2 2+ from aqueous solution on P-MWCNTs was studied as a function of contact time, solid contents, pH, ionic strength and temperature under ambient conditions using batch experiment. Two simplified kinetic models of pseudo-first-order and pseudo-second-order were tested to determine kinetic parameters such as rate constants, equilibrium sorption capacities and related correlation coefficients for kinetic models of the sorption process. It can be seen that the UO2 2+ sorption on P-MWCNTs could be described more favorably by the pseudo-second-order model. The thermodynamic parameters (∆G°, ∆S°, ∆H°) calculated from the temperature-dependent sorption isotherms indicated that the sorption of UO2 2+ on P-MWCNTs were an endothermic and spontaneous processes. The results of the present study suggest that P-MWCNTs can be used beneficially in treating industrial effluents containing radioactive and heavy metal ions.

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Abstract  

There is general consensus that the field of nanotechnology will be very important in the future. An open question is, however, which technological approaches or paradigms will be important in the field. The paper assumes that the carbon nanotube will be a key element of an emerging technological paradigm in nanotechnology. This study employs a bibliometric method — bibliographic coupling — to identify important nanotubes-related ‘leitbilder’ — a concept meaning ‘guiding images’ that provide a basis for different professions and disciplines to work in the same direction. Until recently, bibliographic coupling has been applied rarely for purposes of research evaluation, not to mention technology foresight. Our case study seems to suggest that bibliographic coupling is particularly suitable for anticipating technological breakthroughs. Bibliographic coupling analysis of recent nanotube-related patents focused our attention to recent patents owned by Nantero Inc. Nantero’s main focus is the development of NRAM — a high-density nonvolatile random access memory. The NRAM leitbild seems to be an important emerging leitbild. It connects technical opportunities and promising applications relating to the memories in devices such as cell phones, MP3 players, digital cameras, as well as applications in networking arena.

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Abstract  

The basic principle of comparing the sample mass with the mass of a reference body in equilibrium gives the equal-armed beam balance a unique accuracy. Main parameters characterising the suitability of the instrument are measuring range, resolution and relative sensitivity (resolution/maximum load). The historical development of the values of these parameters achieved depended strongly on the practical need in those times. Technically unfavourable scales of the oldest Egyptian dynasties (~3000 BC) could resolve mass differences of 1 g and had a relative sensitivity of at least 10–3. More sophisticated instruments from the 18th Dynasty (~1567–1320 BC) achieved a relative sensitivity of 10–4 independent of the size of the instrument. In 350 BC Aristotle clarified the theory of the lever and at about 250 BC Archimedes used the balance for density determinations of solids. The masterpiece of a hydrological balance was Al Chazini’s 'Balance of Wisdom’ built about 1120. Its relative sensitivity was 2⋅10–5. Real progress took place when scientists like Lavoisier (1743–1794) founded modern chemistry. At the end of the 19th century metrological balances reached a relative sensitivity of 10–9 with a maximum load of several kilogrammes. That seems to be the high end of sensitivity of the classical mechanical beam balance with knife edges. Improvements took place by electrodynamic compensation (Emich, Gast). In 1909 Ehrenhaft and Millikan could weigh particles of 10–15 g by means of electrostatic suspension. In 1957 Sauerbrey invented the oscillating quartz crystal balance. By observing the frequency shift of oscillating carbon nanotubes or of silica nanorods, masses or mass changes in the attogram or zeptogram have been observed recently.

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, Piedigrosso P, Colomer JF, Mukhopadhyay K, Doome R et al. Synthesis of single- and multi-wall carbon nanotubes over supported catalysts, Appl. Phys. A 1998; 67: 11–22. Doome R. Synthesis of

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, carbon nanotubes (CNT), calcium carbonate (CaCO 3 ), silica (SiO 2 ), titanium oxide (TiO 2 ), and zinc oxide (ZnO), have been added into a polymer matrix for various reasons such as, property improvement and cost reduction [ 1 ]. Polypropylene

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Scientometrics
Authors:
Peng Hui Lv
,
Gui-Fang Wang
,
Yong Wan
,
Jia Liu
,
Qing Liu
, and
Fei-cheng Ma

2004 2 3192 Thess A, Lee R, Nikolaev P Crystalline ropes of metallic carbon nanotubes Rice Quantum Inst

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49 Yang, K., Xing, B. (2009): Adsorption of fulvic acid by carbon nanotubes from water. Environmental Pollution , 157 , 1095–1100. Xing B

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organic treatment of clay and residue investigation on flame retarded properties [ 4 – 11 ]. In the case of polymer/nanocomposites one of the most used fillers are carbon nanotubes (CNTs) and for some time now halloysite nanotubes (HNTs). Carbon

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existed in the CR. Among them, the standard reference should cover author, title, journal, press and page number, like this “M. S. P. Shaffer, et al. “Dispersions of Carbon Nanotubes: Polymeric Analogies”. Department of Materials Science, Cambridge

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network of SG within the matrix. This improvement in thermal conductivity is in a good agreement with what has been reported for adding graphite to Nylon 66 [ 1 ] and epoxy [ 14 ] as well as multi-wall carbon nanotubes to epoxy composites [ 15 ]. Thermal

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