The UV-visible action-absorption spectrum of all-trans and 11-cis protonated Schiff base retinal in the gas phase

2018 ◽  
Vol 20 (10) ◽  
pp. 7190-7194 ◽  
Author(s):  
Jeppe Langeland Knudsen ◽  
Anika Kluge ◽  
Anastasia V. Bochenkova ◽  
Hjalte V. Kiefer ◽  
Lars H. Andersen

The UV-visible absorption of retinal in its protonated Schiff-base form is studied in the gas-phase.

2018 ◽  
Vol 45 (9) ◽  
pp. 0911016
Author(s):  
曹晨鹏 Cao Chenpeng ◽  
郝仕国 Hao Shiguo ◽  
罗宁宁 Luo Ningning ◽  
史久林 Shi Jiulin ◽  
何兴道 He Xingdao

2020 ◽  
Vol 10 (20) ◽  
pp. 7334
Author(s):  
Seung-Hoon Seo ◽  
Byoung-Il Kim

In this study, after firing and powdering Cu, Cr, and S with NP-400 TiO2, an NOx removal rate test was performed according to the ISO test method to analyze the photocatalytic reactivity in visible light. The distribution of the photocatalyst and visible light reactivity on the surface of the test specimen were confirmed through SEM (Scanning electron microscope), EDS (Energy dispersive spectroscopy), XRD (X-ray diffraction), UV-visible absorption spectrum and energy band gap tests. The flowability of UHPC (Ultra high performance concrete) slightly decreased due to the increase in the photocatalyst mixing rate, but both J-Ring and L-Box test results showed that there is no problem when concrete is placed. As a result of SEM and EDS tests, good microstructure and peak values were confirmed in the test specimens doped with Cu, and as a result of the XRD test, anatase and rutile peaks were confirmed in the Cu, Cr, and S specimens. In the UV-visible absorption spectrum analysis, it was confirmed that only the specimen doped with Cu maintains a high absorption power of 0.8 up to 700 nm, and the inherent band gaps are reduced to 2.9 eV, thereby increasing the possibility of reaction in visible light. Finally, as a result of the NOx removal test by the ISO test method, about 15.8% was removed for 5 h in the specimen doped with Cu, and the removal efficiency is estimated to be possible up to about 25% when applied with the TPBRC (transparent plastic bar reinforced concrete).


1986 ◽  
Vol 64 (11) ◽  
pp. 2152-2161 ◽  
Author(s):  
R. A. Back ◽  
J. M. Parsons

The visible absorption spectrum of 1,2-cyclobutanedione has been measured in the gas phase at wavelengths between 4000 and 5100 Å. The absorption is attributed to the allowed π* ← n+, 1B1 ← 1A1 transition corresponding to the first excited singlet state. The spectrum shows a complex well-resolved vibrational structure which has been analysed, with some 125 bands measured and assigned. The bands at the longer wavelengths show sharp rotational fine structure, not yet analysed. The strongest band in the spectrum at 4933 Å has been assigned as the 0–0 band, while a band almost as strong at 4820 Å is attributed to excitation of one quantum of [Formula: see text], the a2 out-of-plane carbonyl bending vibration, and it is suggested that this band owes its intensity to vibronic coupling. A number of symmetric vibrations are also excited in the spectrum, but with no long progressions. Sequence bands running to the blue with an interval of about 72 cm−1 are prominent throughout the spectrum, and are assigned to v13, the a2 ring-twisting vibration. Other hot bands were also observed involving v13 which permitted estimation of energy levels for this vibration both in the ground state and the excited state. The infrared spectrum was also measured and analysed in the gas phase between 600 and 4000 cm−1, and 14 bands were assigned to fundamental vibrations; some of these assignments, at the lower frequencies, are uncertain.


1995 ◽  
Vol 99 (4) ◽  
pp. 1143-1150 ◽  
Author(s):  
John J. Orlando ◽  
James B. Burkholder

2020 ◽  
Vol 32 (5) ◽  
pp. 1039-1042
Author(s):  
Mridula Gupta ◽  
Sheela M. Valecha

A new series of heterocyclic Schiff bases were prepared from condensation of 1-phenyl-3-methyl-4-acetyl/benzoyl-pyrazolone with 4,4′-diaminodiphenylmethane and 4,4′-diaminodiphenyl ether, resulting in the formation of four novel Schiff base ligands. These ligands were then treated with ethanolic solution of PdCl2, to form corresponding palladium(II) complexes. These complexes were characterized by elemental analysis, IR, 1H NMR, TGA, magnetic susceptibility measurements and UV-visible absorption spectroscopy. All the Pd(II) complexes were found to have one coordinated water molecule. Schiff base ligands chelated with the metal atom through two donor sites N and O of azomethine (-C=N-) and phenolic (-OH) groups, respectively.


1991 ◽  
Vol 62 (2) ◽  
pp. 163-171 ◽  
Author(s):  
R. Meller ◽  
W. Raber ◽  
J.N. Crowley ◽  
M.E. Jenkin ◽  
G.K. Moortgat

Sign in / Sign up

Export Citation Format

Share Document