scholarly journals The Adsorption Properties ofBacillus atrophaeusSpores on Single-Wall Carbon Nanotubes

2009 ◽  
Vol 2009 ◽  
pp. 1-6 ◽  
Author(s):  
P. Cortes ◽  
S. Deng ◽  
G. B. Smith
Keyword(s):  
Carbon Nanotubes ◽  
Adsorption Equilibrium ◽  
Effective Diffusivity ◽  
Single Wall Carbon Nanotubes ◽  
Batch Adsorption ◽  
Water Supply Systems ◽  
Single Wall Carbon ◽  
Transmission Electron ◽  
Equilibrium Data ◽  
Adsorption Equilibrium Data

An adsorption equilibrium and a kinetic study ofBacillus atrophaeuson Single-Wall Carbon Nanotubes (SWCNTs) were here performed to provide the basis for developing biosensor devices for detecting threatening micro-organisms in water supply systems.B. atrophaeusspores and carbon nanotubes were subjected to a batch adsorption process to document their equilibria and kinetics. Here, commercial nanotubes were either studied as received or were acid-purified before adsorption experiments. TheBacillusspores appear to show higher affinity towards the purified nanotubes than to the as-received nanomaterial. The effective diffusivity of the spores onto the purified nanotubes was found to be approximately 30 percent higher than onto the as-received nanotubes. It seems that the removal of amorphous carbon from the as-received nanotubes through a purification process yielded an intimate nantoubes-spore interaction as revealed by transmission electron microscopy. Freundlich model successfully correlated the adsorption equilibrium data for the nanotubes-spore interaction. Transmission electron micrographs showed extensive contact between theBacillusand the purified nanotubes, but the association appeared less intimate between the spores and the as-received nanotubes.

scholarly journals Observation and Characterization of Fragile Organometallic Molecules Encapsulated in Single-Wall Carbon Nanotubes

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Daisuke Ogawa ◽  
Ryo Kitaura ◽  
Takeshi Saito ◽  
Shinobu Aoyagi ◽  
Eiji Nishibori ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
High Yield ◽  
Single Wall Carbon Nanotubes ◽  
X Ray Diffraction ◽  
Single Wall Carbon ◽  
X Ray ◽  
Transmission Electron ◽  
Organometallic Molecules ◽  
X Ray Absorption

Thermally fragile tris(η5-cyclopentadienyl)erbium (ErCp3) molecules are encapsulated in single-wall carbon nanotubes (SWCNTs) with high yield. We realized the encapsulation of ErCp3with high filling ratio by using high quality SWCNTs at an optimized temperature under higher vacuum. Structure determination based on high-resolution transmission electron microscope observations together with the image simulations reveals the presence of almost free rotation of each ErCp3molecule in SWCNTs. The encapsulation is also confirmed by X-ray diffraction. Trivalent character of Er ions (i.e., Er3+) is confirmed by X-ray absorption spectrum.

Adsorption Equilibrium and Kinetics of Copper from Aqueous Solutions on Steel Slag

2011 ◽  
Vol 354-355 ◽  
pp. 33-36
Author(s):  
Jian Yun Li ◽  
Quan Xian Hua ◽  
Jun Ling Niu ◽  
Jian Wei Tang ◽  
Ke Xu
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Equilibrium ◽  
Steel Slag ◽  
Adsorption Rate ◽  
Batch Adsorption ◽  
Equilibrium And Kinetics ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Adsorption Equilibrium Data ◽  
Kinetics Of

The adsorption of copper in aqueous solutions by steel slag was studied in batch adsorption experiments. The adsorption equilibrium data fitted best with Langmuir and Freundlich equations. The adsorption was preferential type. A comparison of the kinetics models on the apparent adsorption rate showed that the adsorption system was best described by the pseudo-second-order kinetics. The adsorption rate was controlled by both liquid film diffusion and intraparticle dispersion.

Electrical Resistance of Single-Wall Carbon Nanotubes with Determined Chiral Indices

2009 ◽  
Vol 1204 ◽  
Author(s):  
Letian Lin ◽  
Lu-Chang Qin ◽  
Sean Washburn ◽  
Scott Paulson
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Vapor Deposition ◽  
Electrical Resistance ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Single Wall Carbon Nanotubes ◽  
Single Wall Carbon ◽  
Transmission Electron ◽  
Highly Sensitive

AbstractThe properties of a carbon nanotube (CNT), in particular a single-wall carbon nanotube (SWNT), are highly sensitive to the atomic structure of the nanotube described by its chirality (chiral indices). We have grown isolated SWNTs on a silicon substrate using chemical vapor deposition (CVD) and patterned sub-micron probes using electron beam lithography. The SWNT was exposed by etching the underlying substrate for transmission electron microscope (TEM) imaging and diffraction studies. For each individual SWNT, its electrical resistance was measured by the four-probe method at room temperature and the chiral indices of the same SWNT were determined by nano-beam electron diffraction. The contact resistances were reduced by annealing to typically 3-5 kΩ. We have measured the I-V curve and determined the chiral indices of each nanotube individually from four SWNTs selected randomly – two are metallic and two are semiconducting. We will present the electrical resistances in correlation with the carbon nanotube diameter as well as the band gap calculated from the determined chiral indices for the semiconducting carbon nanotubes. These experimental results are also discussed in connection with theoretical estimations.

Thermodynamics of Cr(VI) Adsorption on Thiourea Chelating Ion Exchange Fiber

2014 ◽  
Vol 894 ◽  
pp. 121-124 ◽  
Author(s):  
Yan Qiang Jian ◽  
Ming Yu Li ◽  
Qing Xuan Zeng
Keyword(s):  
Ion Exchange ◽  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Polypropylene Fiber ◽  
Equation Model ◽  
Batch Adsorption ◽  
Equilibrium Data ◽  
Endothermic Process ◽  
Adsorption Equilibrium Data ◽  
Ion Exchange Fiber

A chelating ion exchange fiber containing thioureido groups for the removal of Cr (VI) has been prepared from chloramethylated styrene grafted polypropylene fiber (2.96 mmol/g Cl) reacted with thiourea, batch adsorption experiments are adopted to investigate its adsorption equilibrium properties, Adsorption isotherms at various temperatures were obtained. Langmuir linear equation model can well describe the adsorption equilibrium data suggesting that the adsorption process involves both chemisorption and physisorption. The values of thermodynamic parameters, including ΔH, ΔGand ΔS, indicate that the adsorption of Cr (VI) is a spontaneous, entropy-driven and endothermic process.

scholarly journals Single Wall Carbon Nanotubes Filled with Metallocenes: a First Example of Non-Fullerene Peapods

2001 ◽  
Vol 706 ◽  
Author(s):  
F. Stercel ◽  
N. M. Nemes ◽  
J. E. Fischer ◽  
D. E. Luzzi
Keyword(s):  
Carbon Nanotubes ◽  
Vapor Phase ◽  
The Other ◽  
Irradiation Damage ◽  
Single Wall Carbon Nanotubes ◽  
Chemical Bonds ◽  
Single Wall Carbon ◽  
X Ray ◽  
Transmission Electron ◽  
Iron Chromium

AbstractWe report the synthesis and analysis of metallocenes (ferrocene, chromocene, ruthenocene, vanadocene, tungstenocene-dihydride) encapsulated in single wall carbon nanotubes (SWNTs). In the case of ferrocene, efficient filling of the SWNTs was accomplished from both the liquid and the vapor phase. The other two metallocenes were filled from the vapor phase. High resolution transmission electron microscopy reveals single molecular chains of metallocenes inside SWNTs. Molecules move under the electron beam in the SWNTs indicating the absence of strong chemical bonds between each other and the SWNT wall. Their movement freezes after short illumination as a result of irradiation damage. Energy dispersive X-ray spectrometry confirms the presence of iron, chromium, ruthenium, vanadium and tungsten.

Adsorption Equilibrium and Kinetics of Microorganisms on Single-Wall Carbon Nanotubes

2008 ◽  
Vol 8 (6) ◽  
pp. 954-962 ◽  
Author(s):  
Shuguang Deng ◽  
Venkata K. K. Upadhyayula ◽  
Geoffrey B. Smith ◽  
Martha C. Mitchell
Keyword(s):  
Carbon Nanotubes ◽  
Adsorption Equilibrium ◽  
Single Wall Carbon Nanotubes ◽  
Single Wall Carbon ◽  
Equilibrium And Kinetics ◽  
Adsorption Equilibrium And Kinetics ◽  
Kinetics Of

Direct Observation of Intercalant and Catalyst Particle in Single Wall Carbon Nanotubes

1999 ◽  
Vol 593 ◽  
Author(s):  
X. Fan ◽  
E. C. Dickey ◽  
P. Eklund ◽  
K. Williams ◽  
L. Grigorian ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Catalyst Particle ◽  
Single Wall Carbon Nanotubes ◽  
Contrast Imaging ◽  
Single Wall Carbon ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Dopant Atoms ◽  
Z Contrast ◽  
Electron Energy Loss

ABSTRACTThe Z-contrast scanning transmission electron microscopy (STEM) imaging technique has been used to study dopant atoms and catalyst particles in single wall carbon nanotubes (SWNT). Iodine and bromine have been doped respectively in arc-grown SWNTs. We have directly observed the dopant sites and distributions. Both dopants appear to be incorporated linearly within the SWNT bundles. SWNT were also grown by pulsed laser ablation with mixed Ni and Co catalyst, and the size and distribution of catalytic particles was studied. By using Z-contrast imaging, we found that the size distribution of the catalyst particles varied over a large range, but even the smallest were larger than the diameter of an individual SWNT. Furthermore, electron energy loss spectroscopy (EELS) is used to determine the composition of individual nanocatalyst particles, and were found to consist of a uniform alloy of Co and Ni.

scholarly journals Flexural Strength of an Indirect Composite Modified with Single-Wall Carbon Nanotubes

2021 ◽  
Author(s):  
Pedro Rogério Camargos Pennisi ◽  
Pedro Urquiza Jayme Silva ◽  
Fábio Scorsolini Valverde ◽  
Ticiane Campos Clemente ◽  
Vitória Cerri ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Flexural Strength ◽  
Composite Resin ◽  
Composite Resins ◽  
Single Wall Carbon Nanotubes ◽  
Single Wall Carbon ◽  
Dental Restorations ◽  
Transmission Electron ◽  
Indirect Composite ◽  
Flexural Resistance

Abstract Objectives The low resistance to fracture has limited the use of indirect composite resins for dental restorations, particularly in regions that are exposed to strong occlusal forces. To overcome this issue, different types of reinforcement for composites have been proposed, one of which is carbon nanotubes (CNTs). The aim of this study was to evaluate the flexural resistance of one commercial indirect composite resin (Sinfony, 3M/ESPE) after incorporation of single-wall carbon nanotubes (SWCNTs; Sigma–Aldrich, Inc., St. Louis, Missouri, United States) with or without the silanization form. Materials and Methods Specimens of composite resin were fabricated in a Teflon mold. The composite resin was prepared according to the manufacturer’s instructions (n = 10 for each group), with SWCNTs in three concentrations. Statistical Analysis The SWCNTs and SWCNT/SiO2-ATES specimens were evaluated by transmission electron microscopy, and a flexural test was conducted according to the ISO 4049/2009. Flexural strength data in MPa were submitted to one-way ANOVA following Tukey (p < 0.05). Results The SWCNTs did not improve the flexural strength of indirect composite resin when compared with the control, independent of the concentration added (p > 0.05). However, when SWCNTs and SWCNTs/SiO2-ATES were compared, the SWCNTs/SiO2-ATES showed higher values than the three concentrations of SWCNTs (p < 0.05). Conclusion The silanization process improves the SWCNTs strength proprieties, but the modification of chemical bonding between SWCNT and SWCNT/SiO2-ATES modified resins, in different concentrations, did not improve the composite resin flexural strength.

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