Absolute measurements of photoabsorption cross sections, photoionization cross sections, and photoionization quantum yields of silane in the 13–40 eV region

1991 ◽  
Vol 95 (3) ◽  
pp. 1456-1460 ◽  
Author(s):  
Kosei Kameta ◽  
Masatoshi Ukai ◽  
Ryo Chiba ◽  
Kazunori Nagano ◽  
Noriyuki Kouchi ◽  
...  
Keyword(s):  
Cross Sections ◽  
Quantum Yields ◽  
Absolute Measurements

Absolute cross sections and quantum yields for chemiluminescent Al+(1S, 3P) + F2, Cl2 collisions

1988 ◽  
Vol 126 (1) ◽  
pp. 125-135 ◽  
Author(s):  
A. Kowalski ◽  
B. Müller ◽  
Ch. Ottinger
Keyword(s):  
Cross Sections ◽  
Quantum Yields

Absolute measurements of electron-loss cross sections ofHe+andC3+with atomic hydrogen at intermediate velocities

1998 ◽  
Vol 58 (2) ◽  
pp. 1204-1211 ◽  
Author(s):  
M. M. Sant’Anna ◽  
W. S. Melo ◽  
A. C. F. Santos ◽  
G. M. Sigaud ◽  
E. C. Montenegro ◽  
...  
Keyword(s):  
Cross Sections ◽  
Atomic Hydrogen ◽  
Electron Loss ◽  
Absolute Measurements

scholarly journals The MPI-Mainz UV/VIS Spectral Atlas of Gaseous Molecules of Atmospheric Interest

2013 ◽  
Vol 5 (2) ◽  
pp. 365-373 ◽  
Author(s):  
H. Keller-Rudek ◽  
G. K. Moortgat ◽  
R. Sander ◽  
R. Sörensen
Keyword(s):  
Cross Sections ◽  
Wavelength Region ◽  
Quantum Yields ◽  
The Internet ◽  
Web Pages ◽  
Data Sets ◽  
Absorption Cross ◽  
Large Collection ◽  
Data Files ◽  
The Web

Abstract. We present the MPI-Mainz UV/VIS Spectral Atlas of Gaseous Molecules, which is a large collection of absorption cross sections and quantum yields in the ultraviolet and visible (UV/VIS) wavelength region for gaseous molecules and radicals primarily of atmospheric interest. The data files contain results of individual measurements, covering research of almost a whole century. To compare and visualize the data sets, multicoloured graphical representations have been created. The MPI-Mainz UV/VIS Spectral Atlas is available on the Internet at http://www.uv-vis-spectral-atlas-mainz.org. It now appears with improved browse and search options, based on new database software. In addition to the Web pages, which are continuously updated, a frozen version of the data is available under the doi:10.5281/zenodo.6951.

Absolute measurements of photoabsorption and photoionization cross sections of disilane in the 13–40 eV region

1991 ◽  
Vol 95 (8) ◽  
pp. 6188-6189 ◽  
Author(s):  
Kosei Kameta ◽  
Masatoshi Ukai ◽  
Norihisa Terazawa ◽  
Kazunori Nagano ◽  
Yuji Chikahiro ◽  
...  
Keyword(s):  
Cross Sections ◽  
Absolute Measurements

scholarly journals Characterisation and improvement of <i>j</i>(O<sup>1</sup>D) filter radiometers

2016 ◽  
Author(s):  
Birger Bohn ◽  
Dwayne E. Heard ◽  
Nikolaos Mihalopoulos ◽  
Christian Plass-Dülmer ◽  
Rainer Schmitt ◽  
...  
Keyword(s):  
Cross Sections ◽  
Spectral Properties ◽  
Solar Spectrum ◽  
Field Measurements ◽  
Correction Method ◽  
Quantum Yields ◽  
Photolysis Frequencies ◽  
Filter Radiometer ◽  
Improved Performance

Abstract. Atmospheric O3 → O(1D) photolysis frequencies j(O1D) are crucial parameters for atmospheric photochemistry because of their importance for primary OH formation. Filter radiometers have been used for many years for in-situ field measurements of j(O1D). Typically the relationship between the output of the instruments and j(O1D) is non-linear because of changes in the shape of the solar spectrum dependent on solar zenith angles and total ozone columns. These non-linearities can be compensated by a correction method based on laboratory measurements of the spectral sensitivity of the filter radiometer and simulated solar actinic flux density spectra. Although this correction is routinely applied, the results of a previous field comparison study of several filter radiometers revealed that some corrections were inadequate. In this work the spectral characterisations of seven instruments were revised and the correction procedures were updated and harmonized considering recent recommendations of absorption cross sections and quantum yields of the photolysis process O3 → O(1D). Previous inconsistencies were largely removed using these procedures. In addition, optical interference filters were replaced to improve the spectral properties of the instruments. Successive determinations of spectral sensitivities and field comparisons of the modified instruments with a spectroradiometer reference confirmed the improved performance. Overall, filter radiometers remain a low-maintenance alternative of spectroradiometers for accurate measurements of j(O1D) provided their spectral properties are known and potential drifts in sensitivities are monitored by regular calibrations with standard lamps or reference instruments.

Synthesis, characterization, photophysical and DNA photocleavage properties of amphiphilic porphyrins

2014 ◽  
Vol 18 (03) ◽  
pp. 221-230 ◽  
Author(s):  
Jie Zhang ◽  
Mingyu Teng ◽  
Dan Li
Keyword(s):  
Cross Sections ◽  
Photophysical Properties ◽  
Photon Absorption ◽  
Quantum Yields ◽  
Two Photon Absorption ◽  
Pyridinium Cation ◽  
H Nmr ◽  
Two Photon ◽  
Porphyrin Derivatives ◽  
Tof Ms

A series of amphiphilic porphyrins appended with pyridinium cation and/or polyethylene glycol have been synthesized and fully characterized by 1 H NMR, IR and MALDI-TOF-MS. Their photophysical properties were determined and the singlet oxygen (1 O 2) quantum yields of these compounds are in the range of 0.30–0.61 in CHCl 3 and 0.048–0.18 in Tris buffer. The measured two-photon absorption (TPA) cross-sections σ(2) of these porphyrin derivatives are between 110 and 240 GM. These amphiphilic porphyrins show some photocleavage activities (10%–21%) towards the anionic DNA observed at 100 μM.

scholarly journals Relative O(1D) Quantum Yields in the near UV Photolysis of Ozone at 298 K

1975 ◽  
Vol 30 (6-7) ◽  
pp. 835-844 ◽  
Author(s):  
G. K. Moortgat ◽  
P. Warneck
Keyword(s):  
Quantum Yield ◽  
Temperature Dependence ◽  
Cross Sections ◽  
Spectral Band ◽  
Monochromatic Light ◽  
Wavelength Region ◽  
Band Width ◽  
Quantum Yields ◽  
Dissociation Limit ◽  
Ozone Absorption

Abstract Mixtures of O3 with excess N2O were photolysed in the wavelength region 290 - 335 nm using monochromatic light with a band width of 4 nm. The resulting primary product atomic singlet oxygen, O(1D), in reacting with N2O produces in part NO which subsequently reacts with O3 giving rise to a weak infrared chemiluminescence. The emission was monitored with a cooled photomultiplier. The emission intensity is directly proportional to the rate of O(1D) production and it has been utilised to derive the relative O(1D) quantum yield as a function of wavelength between 295 and 320 nm. The data were normalised to a quantum yield of unity of 300 nm and corrections were applied to reduce the error resulting from the spectral band width of photolysing radiation. The O(1D) quantum yields show a temperature dependence. At 298 K the quantum yield is unity up to 305 nm, then declines to zero at 319 nm. At the dissociation limit, taken to occur at γ = 310.3 nm, the quantum yields is 0.57, i. e. considerably below unity. The implications of this result as well as the tail toward longer wavelengths and the temperature dependence are discussed. Ozone absorption cross sections are also reported.

Sign in / Sign up

Export Citation Format

Share Document