In situ optical absorption spectroscopy, incandencence, and light-scattering characterization of single-wall carbon nanotube synthesis by the laser vaporization technique

2003 ◽  
Author(s):  
Alexander A. Puretzky ◽  
David B. Geohegan ◽  
C. H. Schittenhelm
Keyword(s):  
Carbon Nanotube ◽  
Light Scattering ◽  
Optical Absorption ◽  
Absorption Spectroscopy ◽  
Optical Absorption Spectroscopy ◽  
Laser Vaporization ◽  
Single Wall Carbon ◽  
Carbon Nanotube Synthesis

Optical Absorption Spectroscopy of DNA-Wrapped HiPco Carbon Nanotubes

2019 ◽  
Vol 943 ◽  
pp. 95-99
Author(s):  
Li Jun Wang ◽  
Kazuo Umemura
Keyword(s):  
Carbon Nanotubes ◽  
Aqueous Solution ◽  
Optical Absorption ◽  
Absorption Spectroscopy ◽  
Near Infrared ◽  
Nir Spectroscopy ◽  
Optical Characterization ◽  
Optical Absorption Spectroscopy ◽  
Double Stranded Dna

Optical absorption spectroscopy provides evidence for individually dispersed carbon nanotubes. A common method to disperse SWCNTs into aqueous solution is to sonicate the mixture in the presence of a double-stranded DNA (dsDNA). In this paper, optical characterization of dsDNA-wrapped HiPco carbon nanotubes (dsDNA-SWCNT) was carried out using near infrared (NIR) spectroscopy and photoluminescence (PL) experiments. The findings suggest that SWCNT dispersion is very good in the environment of DNA existing. Additionally, its dispersion depends on dsDNA concentration.

Use of optical absorption spectroscopy for the characterization of an Ar−Ti magnetron discharge

2007 ◽  
Vol 13 (6) ◽  
pp. 483-488 ◽  
Author(s):  
Nikolay Britun ◽  
Mireille Gaillard ◽  
Yong Mo Kim ◽  
Kab Seog Kim ◽  
Jeon-Geon Han
Keyword(s):  
Optical Absorption ◽  
Absorption Spectroscopy ◽  
Optical Absorption Spectroscopy ◽  
Magnetron Discharge

scholarly journals Chirality Characterization of Dispersed Single Wall Carbon Nanotubes

2005 ◽  
Vol 872 ◽  
Author(s):  
Min Namkung ◽  
Phillip A. Williams ◽  
Candis D. Mayweather ◽  
Buzz Wincheski ◽  
Cheol Park ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Optical Absorption ◽  
Raman Scattering ◽  
Scattering Data ◽  
Resonant Peak ◽  
Optical Absorption Spectroscopy ◽  
Single Wall Carbon Nanotubes ◽  
Sodium Dodecylbenzene Sulfonate ◽  
Single Wall Carbon

AbstractRaman scattering and optical absorption spectroscopy are used for the chirality characterization of HiPco single wall carbon nanotubes (SWNTs) dispersed in aqueous solution with the surfactant sodium dodecylbenzene sulfonate. Radial breathing mode (RBM) Raman peaks for semiconducting and metallic SWNTs are identified by directly comparing the Raman spectra with the Kataura plot. The SWNT diameters are calculated from these resonant peak positions. Next, a list of (n, m) pairs, yielding the SWNT diameters within a few percent of that obtained from each resonant peak position, is established. The interband transition energies for the list of SWNT (n, m) pairs are calculated based on the tight binding energy expression for each list of the (n, m) pairs, and the pairs yielding the closest values to the corresponding experimental optical absorption peaks are selected. The results reveal (1, 11), (4, 11), (5, 12), and (5, 9) among the most probable chiralities for the semiconducting nanotubes. The results also reveal that (4, 16), (6, 12) and (8, 8) are the most probable chiralities for the metallic nanotubes. Directly relating the Raman scattering data to the optical absorption spectra, the present method is considered the simplest technique currently available. Another advantage of this technique is the use of the, E11S, E33S, and E22M peaks in the optical absorption spectrum in the analysis to enhance the accuracy in the results.

scholarly journals Comparison of tropospheric NO<sub>2</sub> vertical columns in an urban environment using satellite, multi-axis differential optical absorption spectroscopy, and in situ measurements

2013 ◽  
Vol 6 (10) ◽  
pp. 2907-2924 ◽  
Author(s):  
D. Mendolia ◽  
R. J. C. D'Souza ◽  
G. J. Evans ◽  
J. Brook
Keyword(s):  
Optical Absorption ◽  
Urban Environment ◽  
Absorption Spectroscopy ◽  
Ground Level ◽  
Remotely Sensed ◽  
Differential Optical Absorption Spectroscopy ◽  
Optical Absorption Spectroscopy ◽  
Vertical Column ◽  
Above Ground Level

Abstract. Tropospheric NO2 vertical column densities have been retrieved and compared for the first time in Toronto, Canada, using three methods of differing spatial scales. Remotely sensed NO2 vertical column densities, retrieved from multi-axis differential optical absorption spectroscopy and satellite remote sensing, were evaluated by comparison with in situ vertical column densities estimated using a pair of chemiluminescence monitors situated 0.01 and 0.5 km a.g.l. (above ground level). The chemiluminescence measurements were corrected for the influence of NOz, which reduced the NO2 concentrations at 0.01 and 0.5 km by an average of 8 ± 1% and 12 ± 1%, respectively. The average absolute decrease in the chemiluminescence NO2 measurement as a result of this correction was less than 1 ppb. The monthly averaged ratio of the NO2 concentration at 0.5 to 0.01 km varied seasonally, and exhibited a negative linear dependence on the monthly average temperature, with Pearson's R = 0.83. During the coldest month, February, this ratio was 0.52 ± 0.04, while during the warmest month, July, this ratio was 0.34 ± 0.04, illustrating that NO2 is not well mixed within 0.5 km above ground level. Good correlation was observed between the remotely sensed and in situ NO2 vertical column densities (Pearson's R value ranging from 0.72 to 0.81), but the in situ vertical column densities were 52 to 58% greater than the remotely sensed columns. These results indicate that NO2 horizontal heterogeneity strongly impacted the magnitude of the remotely sensed columns. The in situ columns reflected an urban environment with major traffic sources, while the remotely sensed NO2 vertical column densities were representative of the region, which included spatial heterogeneity introduced by residential neighbourhoods and Lake Ontario. Despite the difference in absolute values, the reasonable correlation between the vertical column densities determined by three distinct methods increased confidence in the validity of the values provided by each measurement technique.

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