Nearly ubiquitous use in sunscreens o Strong UV absorbers needed for adequate sun protection o Photostability is key to long lived & efficient products Avobenzone (4-tert-butyl-4methoxydibenzoylmethane) o Very high near-UV absorption o Degradation pathways lead to less effective protection M. Yamaji and M. Kida, The Journal of Physical Chemistry A 117 (9), 1946-1951 (2013)
cis-trans isomerization isomerization about single bonds to form rotamers enol-keto tautomerization Key intermediate for photodegradation Found in acetonitrile but not in other solvents A. Cantrell and D. J. McGarvey, Journal of Photochemistry and Photobiology B: Biology 64 (23), 117-122 (2001) M. Yamaji and M. Kida, The Journal of Physical Chemistry A 117 (9), 1946-1951 (2013) Stimulated Emission 350 nm
Transient Absorption Ground State Bleach 350 nm Singular value decomposition (SVD) guides global fitting & analysis Reveals two distinct species: o Fast component is assigned as excited state absorption and stimulated emission o Slow component is vibrationally excited molecules in the ground state tES
Small influence by solvent identity suggests primarily intramolecular IVR Sfeir, M. Visualization and Analysis of Broadband Transient Absorption Data IGOR.6.20.x-4.5. April 29, 2013 350 nm 350 nm Methanol
0.42 0.02 0.24 0.04 0.44 0.03 Timescales suggest three distinct non-chelated enol species involved Amplitude factors from fits provide a crude measure of relative yield
Utilized femtosecond resolved transient absorption experiments probing both in the visible and UV to elucidate a more complete picture of the photoisomerization dynamics of Avobenzone Currently working on calculations to back up our observations with respect to solvent dependence of various signals Avobenzone presents a nice target for vibrationally mediated photoisomerization (VIMP) in solution o Perhaps affect the product distribution in the 266 nm probing data? o The 350 nm mx absorption makes pumping at
400 nm an easy wavelength for vib. + elec. Excitation.
Folk psychology. Common-sense psychology we use in everyday life (in clinical and social psychology, and in economics), understanding, explaining, predicting behavior, as guided by goals, thoughts, and reasons: 'He . must be crazy, for dumping .
The binary search involves bisecting a dataset until a match is made and a similar process occurs here in the merge sort. Merge sorts. We talk about the . recursive. ... in comparison to the bubble sort technique. Disadvantages. More...
Chinook and coho are also counted as either adults or jacks, based on length. ... Both the NOAA Fisheries BiOp and the Northwest Power Planning Council (NPPC) Fish and Wildlife Program establish regional processes for fish passage management.
Backward Design, Assessment, and Rubrics Based on Understanding by Design By Grant Wiggins and Jay McTighe Backward Design Process Identify Desired Results What should students know, understand, and be able to do? "Enduring" Understanding What are the "Big Ideas" and...
Should weigh up to 5 kilos. This is needed to get critical mass. 2- Get some dynamite and put together a timer for the explosives. 3-Next is to get a container for the uranium. You need to attach the two...
Bias Monitoring Package Introduction. Goal: To provide real-time/long-term instrument bias monitoring for instrument performance evaluation. Instrument bias monitoring test using real-time ATMS TDR data has been performed. The JCSDA Community Radiative Transfer Model (CRTM) is used.
Teach me to fish. We are Equal. ... Program communication - word of mouth, brochure, media coverage, partner agency referrals, etc. . . ... It is a local decision on which positions they wish for this entire process or part...
Ready to download the document? Go ahead and hit continue!