p Papers relevant papers links titles authors 23 7980 Possible release of encapsulated material 4 ID: 931198
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Slide1
Sunschreen projectContent: p:Papers (relevant papers; links, titles, authors)……………………………………… 2-3, 79-80Possible release of encapsulated material……………………………………………. 4Metal-to ligand complexes (MLCT) for solar hervesting………………………… 5-6Figs. From KEG´s MS thesis…………………………………………………………………… 7-8Meeting (190208; KEG,AK; major discussion points)…..………………………. 9Umsókn (áætlun, lýsing)……………………………………………………………………….. 10-11Meeting, 190509 (KEG, AK)…………………………………………………………………… 12-24Lifetime end kQ measurements and determinations…………………………….. 26-32Long wavelength emssion (= 2nd order effect)……………………………………… 33The numbering system for the indole unit………………………………………………. 34Fluorescence vs. Phosphorescence quenching of Melatonin (MELH).……. 35IE of quenchers…………………………………………………………………………………….. 36Q abs. spectra (refs.)……………………………………………………………………………….. 37Q vs C=C effects(?)…………………………………………………………………………………. 38-39M* to Q energy transfer(schematic)……………………………………………………….. 40-41phosphorescenece and fluorescenece spectra vs. KI………………………………. 42-43Commenst relevant to „What to do“……………………………………………………….. 44Me vs. KI absorption…………………………………………………………………………………. 45-47comments……………………………………………………………………………………………… 48abs. spectrophotometer settings………………………………………………………………. 49Quencher spectra (refs. In datadase)……………………………………………………… 50Me IP vs ionization threshold……………………………………………………………………. 51Q abs. spectra and thresholds for S1 formation………………………………………… 52-60Energetics vs. spectra,figures………………………………………………………………….. 61-63Heavy atom effect…………………………………………………………………………………….. 64-70Difference spectra……………………………………………………………………………………. 71-72Melatonin energetics vs. absorption and fluorescence spectra……………….. 73Literature survay and interpretations……………………………………………………… 74-77Indole (and indole derivative) spectra…………………………………………………….. 81-82
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Slide2#Papers; URLs (…/journal vol-p0-year.pdf)Authors; titles1https://notendur.hi.is/agust/rannsoknir/Sun/KEG_06.06.2017.pdf Kristján Einar Guðmundsson; The influence of viscosity on the phosphorescence lifetime of folic acid in aqueous room temperature solutions (MS Thesis)2https://notendur.hi.is/agust/rannsoknir/papers/cpc11-796-10.pdf Franco M. Cabrerizo,* Jacob Arnbjerg, M. Paula Denofrio, Rosa Erra-Balsells, and Peter R. Ogilby; Fluorescence Quenching by Oxygen: “Debunking” a Classic Rule3https://notendur.hi.is/agust/rannsoknir/papers/pccp20-24921-18.pdf Tobias Koch, Christiane Höppener, and Nikos L. Doltsinisa; Conformation-dependent phosphorescence emission of individual mononuclear Ruthenium-(II)-bisterpyridine complexes4https://notendur.hi.is/agust/rannsoknir/papers/HBP1-491-95.pdf D.D. LASIC; Applications of Liposomes 5
https://notendur.hi.is/~agust/rannsoknir/papers/AB324-106-04.pdfDouglas D. Banksa and Bruce A. Kerwin; A deoxygenation system for measuring protein phosphorescence
6
https://notendur.hi.is/~agust/rannsoknir/Sun/PSA_Guidebook-2.pdf
HORIBA Scientific; A guidebook to particle size analysis7https://notendur.hi.is/agust/rannsoknir/papers/pcpb69-294-99.pdfM. C. Rath, H. S. Mahal and T. Mukherjee, Photophysics of Melatonin in Different Environments8https://notendur.hi.is/agust/rannsoknir/papers/sapA63-337-06.pdfMohammad Amjadi a, Jamshid L. Manzoori a,∗, James N. Miller b, Study of the heavy atom-induced room temperature phosphorescence properties of melatonin and its analytical application 9https://notendur.hi.is/agust/rannsoknir/papers/sapA116-183-13.pdfAgnieszka Kowalska-Baron ⇑ , Krystian Gałe˛cki, Stanisław Wysocki; Photophysics of indole-2-carboxylic acid (I2C) and indole-5-carboxylic acid (I5C): Heavy atom effect10https://notendur.hi.is/agust/rannsoknir/papers/sapA98-282-12.pdf Agnieszka Kowalska-Baron a,⇑ , Melissa Chan b , Krystian Gałe˛cki a , Stanisław Wysocki a , Photophysics of indole, tryptophan and N-acetyl-L-tryptophanamide (NATA): Heavy atom effect11https://notendur.hi.is/~agust/rannsoknir/papers/saA51-1691-95.pdf R.M. Linares, A. Gonz~ilez, J.H. Ayala, A.M. Afonso, Venerando Gonzfilez *, Protolytic equilibria of indole and several indolecarboxylic acids in micellar media; abs. and fl. Spectra. 12https://notendur.hi.is/~agust/rannsoknir/papers/jpcA103-8585-99.pdf Prakriti Ranjan Bangal and Sankar Chakravorti*, Excited State Proton Transfer in 2-carboxylic Acid and Indole-5-carboxylic Acid; ….abs. and fl. spectra 13https://notendur.hi.is/~agust/rannsoknir/papers/jacs92-6281-70.pdf ; CONT: slide Dwaine 0. Cowan2 and Ronald L. E. Drisko, The Photodimerization of Acenaphthylene. Heavy-Atom Solvent Effects; ….quenching effect of HA
2
Slide3#Papers; URLs (…/journal vol-p0-year.pdf)Authors; titles14https://notendur.hi.is/~agust/rannsoknir/papers/acr11-334-78.pdf JOSEPH C. KOZIAR and DWAINE 0. COWA, Photochemical Heavy-Atom Effects…increasing phosphorescence15https://notendur.hi.is/~agust/rannsoknir/papers/ac47-1199-75.pdf Paul G. Seybold Wayne White , Room Temperature Phosphorescence Analysis: Use of the External Heavy-Atom Effect …increasing phosphorescence16https://notendur.hi.is/~agust/rannsoknir/papers/jpc81-2035-77.pdf Wayne White and Paul 6. Seybold, External Heavy-Atom Effect on the Room-Temperature Luminescence of Adsorbed Dye; …increasing phosphorescence17https://notendur.hi.is/~agust/rannsoknir/papers/jmstr433-203-98.pdf Giuliano Alagonaa, *, Caterina Ghioa , Susanna Montib, The effect of small substituents on the properties of indole. An ab initio 6-31G* study 18https://notendur.hi.is/~agust/rannsoknir/papers/jmstr688-79-04.pdf Barbara Morzyk-Ociepaa , Danuta Michalskab,*, Adam Pietraszko, Structures and vibrational spectra of indole carboxylic acids. Part I. Indole-2-carboxylic acid19https://notendur.hi.is/~agust/rannsoknir/papers/jcp52-2964-70.pdf GARY G. GIACHINO AND DAVID R. KEAR:-JS, Nature of the External Heavy-Atom Effect on Radiative and N onradiative Singlet-Triplet Transitions* 20https://notendur.hi.is/~agust/rannsoknir/papers/pu48-231-05.pdf K N Solovyov, E A Borisevich, Intramolecular heavy-atom effect in the photophysics of organic molecules21https://notendur.hi.is/~agust/rannsoknir/papers/cc27-1-2018.pdf Hiroyuki Mieno1,2, Ryota Kabe 1,2 & Chihaya Adachi, Reversible control of triplet dynamics in metalorganic framework-entrapped organic emitters via
external gases22https://notendur.hi.is/agust/rannsoknir/papers/saA60-3213-04.pdf
Boris Minaev, Theoretical study of the
external heavy atom effect
on phosphorescence of free-base porphin molecule23https://notendur.hi.is/agust/rannsoknir/papers/jpc86-22-82.pdf Yuko Shlmlzu and Tohru Azuml„, Mechanism of External Heavy Atom Effect on Intersystem Crossing in Fluid Solutions. Analysis Based on Fluorescence Decay Data 24https://notendur.hi.is/agust/rannsoknir/papers/jl17-449-78.pdf Jan NAJBAR, Janina RODAKIEWICZ-NOWAK, EXTERNAL HEAVY ATOM EFFECT ON THE TRIPLET STATE OF AROMATIC HYDROCARBONS IV. FLUORENE, TRIPHENYLENE-d12 AND CORONENE25https://notendur.hi.is/agust/rannsoknir/papers/pcc3-18-00.pdf Mário N. Berberan-Santos, External heavy-atom effect on fluorescence kinetics26https://notendur.hi.is/agust/rannsoknir/papers/jcp53-4512-70.pdf ; CONT: slide 79R. H. HOFELDT, R. SARAI, AND S. H. LIN, Heavy Atom Effect on the Phosphorescence of Aromatic Hydrocarbons. II. Quenching of Perdeuterated Naphthalene by Alkali Halide* 3
Slide44https://notendur.hi.is/agust/rannsoknir/papers/HBP1-491-95.pdf :
Slide5http://rossi.chemistry.uconn.edu/workshop/files/oled_exercise.pdf /https://notendur.hi.is/agust/rannsoknir/Sun/oled_exercise.pdf ::5
Slide6Relevant spectra:http://rossi.chemistry.uconn.edu/workshop/files/oled_exercise.pdf /https://notendur.hi.is/agust/rannsoknir/Sun/oled_exercise.pdf MLCT=Metal-to-ligand charge transfer6
Slide7https://notendur.hi.is/agust/rannsoknir/Sun/KEG_06.06.2017.pdf / #1: 7
Slide8https://notendur.hi.is/agust/rannsoknir/Sun/KEG_06.06.2017.pdf / #1: 8
Slide9Meeting, 190208 (KEG, AK):KEG has made and „installed“ (in RH) a moveable experimental kit for preparing samples for phosphorescencestudies (oxygen scavenger, pump, N2(g) cylinder, 1 x 0.4 cm2 cell (1x1 cm2 cell to come)KEG makes a list of sensitizers to study (both natural and „unnatural“ products)Performe literature survey relevant to,- the compounds spectroscopy (absorption, fluorescenec, phosphorescence)- photochemistryFind best/suitable way for the group (computer) communication (Dropbox, locked directory(?)…)Make a realistic research plan with the aim of publishable data / positive results.Meeting with Kristberg next week/soon9
Slide10Lýsing: Photosensitive delivery systems. Delivery systems encapsulate bioactive components to protect themfrom reacting prematurely with compounds in their environment and to deliver them to their activesites. For the system to act in an optimal manner the delivery system needs an opening mechanismtriggered by the need for the bioactive. For the release of sunscreens an increase in light intensity isthe trigger. Zinc porphyrin sensitizers for dye-sensitized solar cells have been developed [34] andsensitivity has been increased by use of cobalt [36]. A light sensitive zinc porphyrin photosensitizerwas proposed for liposomes by [37] but the compounds are not food grade and therefore not suitablefor TARAMAR products. We have recently initiated the development of methods to evaluate potentialphotosensitizers from materials generally recognizes as safe (GRAS) in foods and an MS studentwho defended his thesis in May 2017 [38] has evaluated the photosensitivity of folic acid.Application (TARASÓL-The pioneering bio-marine Sunscreen):WP4. Photosensitive opening mechanismVörður: V4.1 Luminescence effects of selected compounds identifiedV4.2 Effect of selected compounds on the oxidative state of phospholipids identifiedV4.3 Compounds suitable as an opening mechanism for liposomes containing sunscreen bioactivesselected10
Slide11Lýsing:WP 4.1 Analysis and characterization of photosensitivity, lifetimes and luminescence responses ofvarious food grade compounds including B-vitamins, porphyrin ring containing compounds likechlorophyll and hemoglobin containing compounds and selected other natural colors using a HoribaFluorimeter with a Xenonpulsex phosphor lamp connected to a Fluoro-Hubstation.WP 4.2 Evaluation of the effect of selected compounds on the oxidative state of phospholipidsWP 4.3 Evaluation of the ability of selected compounds to open liposomes with sunscreen bioactivesas a function of increased light intensity and wavelengths (AK added 190209)Comments:1) Could some of the extracted sunscreen bioactive possibly act as “openers”/sensitizer ? 2) Concerning WP 4.3: Possible experimental procedures could involve, a) -to detect the opening process for samples with and without “openers”/sensitizers; b) The detection might involve different absorption (or fluorescence) behaviour of the “openers”/sensitizers inside and outside the liposomes(?)c) We need to consider what light source(s), with variable intensity and wavelengths, are needed/suitable.
11
Slide12Meetitng with KEG, Wednesday, 8.5.2019: project status1. Fluorescence and phosphoresecence experiments:1.1 NATA : N-acetyltryptophanamide: http://www.chemspider.com/Chemical-Structure.10710046.htmlVs. https://www.sigmaaldrich.com/catalog/product/sigma/a6501?lang=en®ion=IShttps://www.sigmaaldrich.com/catalog/product/sigma/t4196?lang=en®ion=ISVs.
Slide13…Dropbox/Kristjan Einar PhD/Kristjan/mælingar/Presentation1.ppx
Slide14…Dropbox/Kristjan Einar PhD/Kristjan/mælingar/NATA-emission-graf
Slide15https://www.edinst.com/wp-content/uploads/2015/04/AN39_StoppedFlow.pdfAbs. and fluorescenec of NATA (from the literature ):Good agreement with KEG data (slides 12-13)
Slide16Lifetime measurements: 280 nm excitation, 359 nm emission (bandpass: 4 nm)…Dropbox/Kristjan Einar PhD/Kristjan/mælingar/30-4-19-Nata-fluorescence-lifetime-stillingar…
Slide17Lifetime measurements: Analysis:…Dropbox/Kristjan Einar PhD/Kristjan/mælingar/30-4-19-NATA-Fluorescence-lifetime-graf…
Slide18What are the results of KEG´s lifetime measurements?Literature measurements:https://notendur.hi.is/~agust/rannsoknir/papers/AB324-106-04.pdfShow schematic figrue of KEG´s equipments
Slide19https://notendur.hi.is/~agust/rannsoknir/papers/AB324-106-04.pdf
Slide20Fluorescence and phosphoresecence experiments:1.2 Riboflavin:https://en.wikipedia.org/wiki/Riboflavin Fluorescenec and lifetime measurements: ???
Slide212. Glycerol / function of:KEG uses glycerol to enhance the T formation and lifetime : assuming that glycerol hinders oxygen quenching of the T state.3. Lyposomes:KEG, in collaboration with Ragnhildur, formes lyposomes:They try to improve the process of making „one-distributions“ (rather than „two-distributions“):
Less than 1
m
m
NB: particle > 1mm is an indication of „dust“/“garbage“Particle sizehttps://notendur.hi.is/~agust/rannsoknir/Sun/PSA_Guidebook-2.pdf
Slide22Use dynamic light scattering technique to evaluate particle sizes:
Slide234. Kristín and Natalia are „extracting“ organic sunscreen mixtures/compounds (X) and determining its absorption spectraMore information needed5. Test to be made (KEG): perform analyses a) without and b) with photosensitizer/ „Openers“XhnAnalyseX
h
n
Analyse
ooooO = „Openers“a) b) Could the X´s act directly as „Openers“
Slide24Comments and questions:Try lifetime measurements without oxygen scawanger, in case that it does harm the measurementsPerform literature survey on phospholipide absorption data/spectraFind a „good“ standard (not necessarily) unon-toxic for lifetime measurementsWhat is the status of getting appropriate luminescence sources (to imitate sun light(?))The opening process (#6 above and slide7) sound a bit „farfetched“ (langsótt): could other species apart from O2(radicals; fragment species) act analogous to O2?See red markings above.6) KEG´s et al. idea is that the opening mechanism involves:Transfer of the „Operners“ / O´s energy in its T state (O(T)) to oxygen (O2(T)) to form singlet O2 (O2 (S)) followed by its reaction with unsaturated phospholipides in the lyposomes to distort the lyposome structure, hence to open it.(see slide 7 above)… is there some solid literature which could support this idea?KEG EDIT: https://www.ncbi.nlm.nih.gov/pubmed/30457340These decyl-pterins led to efficient intercalation in large unilamellar vesicles and produced, under UVA irradiation, singlet molecular oxygen, a highly oxidative species that react with polyunsaturated fatty acids (PUFAs) to form hydroperoxides ….. Here, we demonstrate that the association of 4-(decyloxy)pteridin-2-amine ( O-decyl-Ptr) to lipid membranes is key to its ability to trigger phospholipid oxidation in unilamellar vesicles of phosphatidylcholine rich in PUFAs used as model biomembranes… These primary products undergo a rapid conversion into short-chain secondary products by cleavage of the fatty-acid chains, some of which are due to subsequent photosensitized reactions. As a consequence, a fast increase in membrane permeability is observed
Slide25https://notendur.hi.is/agust/rannsoknir/papers/sapA63-337-06.pdf =>
Slide26Rough fit for the „8ml CHCl3 point“ excluded t0/tConc. Q (g/L)…heima/Kristberg-sunscreens/27-28-okt.odshttps://notendur.hi.is/agust/rannsoknir/KGE/27-28-okt.xlsx
Slide27…heima/Kristberg-sunscreens/M-CHCl3-201103a.pxp; Lay0, Gr0ml CHCl3= 01248Time/nsln(I)Broken lines: parabole fitsSolid lines: line fits
https://notendur.hi.is/agust/rannsoknir/KGE/M-CHCl3-201103a.pxp;Lay0,Gr0
Slide28ómarktækt1248ml CHCl3= 0…heima/Kristberg-sunscreens/M-CHCl3-201103a.pxp; Lay0, Gr0Time/nsln(I)https://notendur.hi.is/agust/rannsoknir/KGE/M-CHCl3-201103a.pxp;Lay0,Gr0
Slide29ml CHCl3= 0…heima/Kristberg-sunscreens/M-CHCl3-201103a.pxp; Lay1, Gr1Time/nspntt0…heima/Kristberg-sunscreens/M-CHCl3-201103a.pxp; Gr275t0 = 126ms pntk=1/t (ns-1)t(ns)t(micros)3016.71E-06
1.49E+05149.0979574
250
6.99E-06
1.43E+05143.1495772007.22E-061.38E+05138.43896231507.42E-061.35E+05134.68557651007.79E-061.28E+05128.3499333757.91E-061.26E+05126.3966834507.81E-061.28E+05128.027858925
7.47E-06
1.34E+05
133.9207992
…heima/
Kristberg-sunscreens
/27-28-okt.ods
Line
fits
ln(I)
t
0
= 149
m
s
https://notendur.hi.is/agust/rannsoknir/KGE/27-28-okt.xlsx
https://notendur.hi.is/agust/rannsoknir/KGE/M-CHCl3-201103a.pxp
;Lay1,Gr1
https://notendur.hi.is/agust/rannsoknir/KGE/M-CHCl3-201103a.pxp
;Gr2
Slide30pntk=1/t (ns-1) ± dev.t(ns)t(micros)3016.71E-066.84e-0081.49E+05149.09795742506.99E-06 7.52e-0081.43E+05143.1495772007.22E-068.56e-0081.38E+05138.43896231507.42E-06
1.18e-0071.35E+05
134.6855765
100
7.79E-06 1.92e-0071.28E+05128.3499333757.91E-062.81e-0071.26E+05126.3966834507.81E-065.06e-0071.28E+05128.0278589257.47E-061.41e-0061.34E+05133.9207992
Slide31ln(I)tfosfórljómunbakgrunnurmælisvið
Slide32Original data:Frumgögn: I vs tfor 0 ml CHCl3pnt I …heima/Kristberg-sunscreens/27-28-okt.ods; M-CHCl3https://notendur.hi.is/agust/rannsoknir/KGE/27-28-okt.xlsx; M-CHCl3 https://notendur.hi.is/agust/rannsoknir/KGE/M-CHCl3-201103a.pxp;Gr4
Slide33https://notendur.hi.is/agust/rannsoknir/papers/sapA63-337-06.pdf =>KEG201103: decided to check lifetime of the long wavelength emissionSecond order emission
Slide34https://notendur.hi.is/~agust/rannsoknir/papers/jmstr433-203-98.pdf The numbering system for the indol unit:
Slide35Fluorescence quenching vs. Phosphorescence quencing (201202; ON Messenger):See: Melatonin fluorescence kq.kq(fl)ratioCH2Cl25.40E+07CHCl31.00E+10185.1852CCl41.70E+101.7https://notendur.hi.is/agust/rannsoknir/KGE/27-28-okt.xlsx, sheet: kq https://notendur.hi.is/agust/rannsoknir/papers/pcpb69-294-99.pdf, #7 in slide 2
Slide36CH2Cl2: https://webbook.nist.gov/cgi/cbook.cgi?Formula=CH2Cl2&NoIon=on&Units=SI&cIE=on IE:CHCl3: https://webbook.nist.gov/cgi/cbook.cgi?Formula=CHCl3&NoIon=on&Units=SI&cIE=on CCl4: https://webbook.nist.gov/cgi/cbook.cgi?Formula=CCl4&NoIon=on&Units=SI&cIE=on CH2Br2: https://webbook.nist.gov/cgi/cbook.cgi?Formula=CH2Br2&NoIon=on&Units=SI&cIE=on CHBr3: https://webbook.nist.gov/cgi/cbook.cgi?Formula=CHBr3&NoIon=on&Units=SI&cIE=on
Slide37It is worth combining absorption spectra (from the data base) of the quenchers *used, to see shift of singlet excited states*Cl containing quenchersBr containing quenchersCH2Cl2CH2Br2CHCl3CHBr3CCl4(CBr4)Cl containing quenchersBr containing quenchersCH2Cl2; ATHhttp://joseba.mpch-mainz.mpg.de/spectral_atlas_data/cross_sections_plots/Halogeno-alkanes+radicals/Bromoalkanes/CH2Br2_210-295K_174-290nm_lin.jpg?fbclid=IwAR0tTIpALYStF1nv_vgDq2IwcreSw-i9hVbv5ZTf02nz12t-TdhIWvjyQmw CHCl3; ATHhttp://joseba.mpch-mainz.mpg.de/spectral_atlas_data/cross_sections_plots/Halogeno-alkanes+radicals/Bromoalkanes/CHBr3_210-295K_lin.jpg?fbclid=IwAR01lyGTrNoUzomsqtruBz1oEKVduHrfiViRu8TBv6jP8CvGnen8Heo_zyU http://joseba.mpch-mainz.mpg.de/spectral_atlas_data/cross_sections_plots/Halogeno-alkanes+radicals/Chloroalkanes/CCl4_160-275nm_lin.jpg http://joseba.mpch-mainz.mpg.de/spectral_atlas_data/cross_sections_plots/Halogeno-alkanes+radicals/Bromoalkanes/CBr4_lin.jpg ..
Slide38C – X :::M*C – X
.
:
:
..C + X dissociationQ; X = halogens*s*nbnb
Slide39C –CM*ps
p*
C –C
(p)
sp*.C –C
(p)
s
p*
.
rotation
..
C=C
..
Slide40n=2n=3n=4Energy0 QQuencherM(S0)M*(S1)M*(T1)
Accessable
hidden
/ T
states for Q (?)S0 MMelatoninl(nm)STTTSS
2
3
n=4
Abs
.
schematic
Slide41n=2n=3n=4Energy0 QQuencherM(S0)M*(S1)M*(T1)
Accessable
hidden
/ T
states for Q (?)S0 MMelatoninl(nm)ST´sT´sT´sSS
2
3
n=4
Abs
.
schematic
Slide42Low KI (0.4M)High KI(1.2M)I(rel.)l/nmhttps://notendur.hi.is/agust/rannsoknir/KGE/KI-210428KEG-210428AK.pxp ; Gr1https://notendur.hi.is/agust/rannsoknir/KGE/KI-210428AK.xlsx sheet: „KI“
Slide43Low KIHigh KIDifference=Low KI – high KII(rel.)l/nmFluorescenceOriginal spectrahttps://notendur.hi.is/agust/rannsoknir/KGE/KI-210428KEG-210428AK.pxp ; Gr2
Slide44Try / comments:–to add medium KI concentration FL-spectra and derive a „Difference spectrum“ (analogous to slide 43) to see if the structure is the same and possibly only intensity changes.-to perform KI quenching (SV-plot) experiments and relevant analysis.-to record absorption spectra for different (low and high) KI concentrations.-to include Q = CHBr3 quenching experiment as planned.Should we try „a –C=C-C=C- quencher system“ by analogy with possible Melatonine to Lyposome energy transfer?What system?... Aromatic compound(?). Could we simply use bensene? What is bensene solubility in water
?Excite the second absorption peak, corresponding to the S0
-> S2
transition
(ca. 222 nm) and record fluorescence & phosphorescence spectra for „low KI“ and „high KI“ to see if it is the S1 -> S0 fluorescence which is being reduced because of S1 -> T1 ISC (enhanced by KI) <= based on evaluation of a „Difference spectrum“(?). If this is the case it would be a clear evidence for the Kashas rule (https://en.wikipedia.org/wiki/Kasha%27s_rule#:~:text=Kasha's%20rule%20is%20a%20principle,state%20of%20a%20given%20multiplicity. )Make figure of quenchers absorption spectra from data base combined: a) Cl containing Q´s, b) Br containing Q´sand mark thresholds corresponding to S0 -> S1 transitionspH áhrif.: Abs. Spectra fyrir pH = 8.8.; ath tækjastillingar fyrir abs. Mælingar.
Slide45KI, 0M, waves 1 vs. 0KI, 0.4 M, waves 5 vs. 4KI, 1.2 M, waves 3 vs. 2https://notendur.hi.is/agust/rannsoknir/KGE/ki-abs-spectra-210504KEG-AK.pxp ; Gr0?; see slide 46Án buffers og Sulfit.Absorption spectra
Slide461.2 M KI (1800 microL)0.4 M KI (600 microL)0 KIRef: Messenger 210506 <= KEG
Slide47https://www.researchgate.net/publication/307529445_Production_and_Drug_Release_Assesment_of_Melatonin-Loaded_AlginateGum_Arabic_Beads/figures?lo=1 Absorption spectrum from the literature:
Slide48Minnispunktar / Athugasemdir: "Heavy atom effect" sem er að hafa áhrif á spin-orbit kúplun (S1<->T1) gæti haft áhrif á tilfærslulíkur (e. transition probabilities) fyrir S0 -> S1.> S1.Þannig gæti S1 ástandið verið mismikið "blandað" ("hybridizerað") háð magni I-(?) T.d. gæti S1 verið nánast "hreinræktað" singlet ástand án I- en haft aukinn "triplet character" í návist I- (?). Í því tilviki gæti hins vegar gleypnin minnkað (og bjagast(?)) með auknum I- styrk (?).The appearance of a spectrum peaking near 350 nm in abs. suggests that a low energy S state (S1(?)), which is not accessable for pure (no KI) Melatonine becomes accessable via I
- / heavy atom effect.
NB: the Abs. spectra (slides 45-46) were recorded
without
a pH = 8.8 buffer used for the FL and Ph dataERGO: pH = 7; hence higher H+ concentration. This might affect an equilibrium ofMe + H+ = MeH+ where H+ is attached to the N atom (?). Judging from KEG the 350 nm peak in the Abs. spectrum disappeared as the pH was brought up to 8.8. ERGO the lower energy Abs. Spectra could be due to MeH+ (?)
Slide49Abs. Spectrometer:
Slide50*CBr4: http://satellite.mpic.de/spectral_atlas/cross_sections/Halogeno-alkanes+radicals/Bromoalkanes/CBr4.spc?fbclid=IwAR2WNWOgokL2deddfooPyNwzysVVwFu_vsJqWbglzsj8Fz-wiRLA5Y3Kiio CHBr3: http://joseba.mpch-mainz.mpg.de/spectral_atlas_data/cross_sections_plots/Halogeno-alkanes+radicals/Bromoalkanes/CHBr3_210-295K_lin.jpg?fbclid=IwAR2zJ3khWP9UILJm7oCxmnE9-iAqV8bF3e8TZFxgMDfAOMI-qV9Fu6SPsQ8 CH2I2:http://joseba.mpch-mainz.mpg.de/spectral_atlas_data/cross_sections_plots/Halogeno-alkanes+radicals/Iodoalkanes(C,H,F,Cl,Br,I)/CH2I2_273-348K_lin.jpg?fbclid=IwAR2CKxRvQ_ZcxbXC0nVqRYA8d0WIcJ71LeYgxy39oAlK_x6CiFUcHZc5CAQ CH2Br2: http://joseba.mpch-mainz.mpg.de/spectral_atlas_data/cross_sections_plots/Halogeno-alkanes+radicals/Bromoalkanes/CH2Br2_210-295K_174-290nm_lin.jpg?fbclid=IwAR11QtgY96uFImaLVCVnAPi9V9pHyRP7SsGhU44JoKk80HZVeItfK1mk4Z4 *CCl4: http://satellite.mpic.de/spectral_atlas/cross_sections/Halogeno-alkanes+radicals/Chloroalkanes/CCl4.spc?fbclid=IwAR1k_RygqJty-U4ObW0elhVLUbXW59tuZX-4v-mvsIy77ojLL8-9WQlkGSY *Gagnabanki:http://satellite.mpic.de/spectral_atlas/?fbclid=IwAR3HOKgkqG45l90ipo7lESZvyl_yZhPKR1MMZlNVC83y7pWGvTfzPDN0pU0 Q spectra:
Slide51Melatonin IP: https://webbook.nist.gov/cgi/cbook.cgi?ID=C73314&Mask=20#Ion-Energetics IE(Me)=7.03eV5.67E+04cm-1/eV1.76E+02nmfactor=8.07E+03cm-1/eVhttps://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: IE-Me Quenchers:CH2Cl2 CH2Br2CHCl3 CHBr3CCl4
Slide52CH2Cl2Threshold ca. 210 nmUse https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Q spectra“
Slide53CHCl3Threshold ca. 220 nmUse: 295 Khttps://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Q spectra“
Slide54CCl4Threshold ca. 245 nmUse: CCl4JPL-2010(2011)295-298K174-275nm(rec)https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx
; sheet: „Q spectra“
Slide55l/nmAbs. s for QThresholdsFor S0 -> S1For Q:245220210Me abs.arb. int. units290excitationS0 -> S1 (Me)CH2Cl2CHCl3CCl4https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra.pxp ; Gr:3https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Q spectra“
Slide56n/cm-1Abs. s for QThresholdsFor S0 -> S1For Q:245220210Me abs.arb. int. unitsExcitation=290 nm/34483 cm-1S0 -> S1 (Me)CH2Cl2CHCl3CCl4https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra.pxp ; Gr:6https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Q spectra“
Slide57CH2Br2Threshold ca. 280 nm
Slide58CHBr3Threshold ca. 338 nmThreshold ca. 290 nm
Slide59l/nmAbs. s for QThresholdsFor S0 -> S1For Q:295280Me abs.arb. int. units290 excitationS0 -> S1 (Me)CH2Br2CHBr3https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra.pxp ; Gr:10https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Q spectra“
Slide60n/cm-1Abs. s for QThresholdsFor S0 -> S1For Q:295280Me abs.arb. int. unitsS0 -> S1 (Me)CH2Br2CHBr3https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra.pxp ; Gr:11https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Q spectra“Excitation=290 nm/34483 cm-1
Slide61CH2Cl2CHCl3CCl4S1S1S1TTT
S1(Me,max)
S1(Me,min
)
S1(Me,290 nm)Me, abs.Q =E/ cm-1S0S0S0S0hnS2(Me)
https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra.pxp
;
Gr
:12
https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx
;
sheet
: „
Energetics
“
S
1
Slide62CH2Br2CHBr3S1S1TTS1(Me,max)S1(Me,min)S1(Me,290 nm)Me, abs.
Q =
E/ cm-1
S
0S0S0hnS2(Me)https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra-1.pxp ; Gr:12https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Energetics“S1
Slide63https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra-1.pxp ; Gr:13E/ cm-1Me,abs.Me,1.2M KI,Buffer;Expanded spectrumAbs.T1I(phosph.)Me+ 1.2M KIS1
I
-
https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx
; sheet: „Energetics“Melatonin energetics vs. absorption and phosphorescence spectra290 nm457 nm350 nm
?
https://notendur.hi.is/agust/rannsoknir/KGE/absorbance_11-05-21KEG.pxp
;Gr3 (
expanded
spectrum
)
S
0
Slide64Heavy atom effect:https://www.sciencedirect.com/science/article/pii/S1386142504001398 https://notendur.hi.is/agust/rannsoknir/papers/saA60-3213-04.pdf
Slide65Slide66I-Me
Slide67https://aip.scitation.org/doi/abs/10.1063/1.1673425 https://notendur.hi.is/~agust/rannsoknir/papers/jcp52-2964-70.pdf
Slide68Messenger skrif, 210514 (AK<->KEG):"Heavy atom effect" hafa ekki bara áhrif á S1 <-> T1, ISC heldur einnig á líftíma fosfórljómunarinnar (vegna blöndunar S1 og T1 ástandanna), þannig að líftími T1 minnkar með vaxandi heavy atom effect. Við þurfum því að íhuga hvort aförvunin, sem vex með auknum fjölda Cl atóma í quencher (CH2Cl2 < CHCl3 < CCl4) og við það að fara frá Cl í Br (CH2Cl2 < CH2Br2) sé vegna "Heavy atom effects (þ.e. vegna vaxandi segulvægis halogen atóm kjarnanna) frekar en vegna "radiationless transition" frá Me*(T1) yfir á Q(T) (þ.e. vegna breytilegrar virkjunaroku).þar sem segir "Radiative T1 S0 transitions are much more susceptible to a heavy‐atom effect than are the corresponding radiationless transitions." Sjá t.d. grein: https://aip.scitation.org/doi/abs/10.1063/1.1673425 þar sem segir "Radiative T1 <-> S0 transitions are much more susceptible to a heavy‐atom effect than are the corresponding radiationless transitions."Mér finnst hins vegar að þessi mikla breyting í kQ (um margar stærðargráður t.d. við að fara frá CHCl3 í CCl3 og úr CH
2Cl2 í CH2Br
2) vera vísbending um áhrif lækkandi virkjunarorku, sem kemur fýrir í veldisvísi hraðafasta (?)
Trúlega er aförvunin sambland af báðum þessum áhrifum og spurningin um hvor þátturinn er meira ráðandi.
Það væri gott að finna fleiri (og nýrri) greinar með dæmum um aförvun vs. "heavy atom effects".Það gæti verið að quenching áhrif KI (I-), og ákvörðun á kQ fyrir I- gæti hjálpað okkur við að skilja þetta, því þar vitum við að áhrifin eru fyrst og fremst "Heavy atom effect"!
Slide69Ath I quantum numbers for Cl and Br:http://mriquestions.com/predict-nuclear-spin-i.html 3/2 both for 35Cl and 37Cl:https://en.wikipedia.org/wiki/Isotopes_of_chlorine
Slide70https://dnpnmr.weebly.com/miscellaneous.html See gyromagnetic ratioValues forCl, Br and I
Slide71Me(mu)0 KI Me(mu)0.4 M KIMe(mu)1.2M KIDIFFDIFFl/nmMostly S1 is „quenched“ by KI:By S1 -> T1 ISC S1S1https://notendur.hi.is/agust/rannsoknir/KGE/flurljomun_210512KEG.pxp ; Gr:4
https://notendur.hi.is/agust/rannsoknir/KGE/flurljomun_210512KEG.pxp ; Gr:5
https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „F_-spectra“
Fluorescence
and Difference spectra
Slide72Fluorescence Difference spectraMe in waterMe(mu)0 KI – Me(mu)1.2M KIMe(mu)0 KI – Me(mu)0.4 M KIl/nmMe(mu)0.4 KI – Me(mu)1.2 M KIhttps://notendur.hi.is/agust/rannsoknir/KGE/flurljomun_210512KEG.pxp ; Gr:7
Slide73E/ cm-1Me,abs.Me,1.2M KI,Buffer;Expanded spectrumAbs.T1S1I-290 nm
I(fluorescence)
S
1
-> S0Me,FL. 0KIhttps://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra-2.pxp ; Gr:13https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; S0Melatonin energetics vs. absorption and fluorescence spectra
Slide74https://notendur.hi.is/~agust/rannsoknir/papers/jpc81-2035-77.pdf; #16
Slide75https://notendur.hi.is/agust/rannsoknir/papers/pcpb69-294-99.pdfkQ for CHCl3 and CCl4 are larger than for KI:kQ for KI is HAE in nature, HAE for CHCl3 and CCl4 will be a lot less. Therefore, quenching by CHCl3 and CCl4Is likely to be different in nature, i.e. Due to energy transfer.Also: kQ for CHCl3 and CCl4 is comparable to kQ for O2 which is due to energy transfer.https://notendur.hi.is/agust/rannsoknir/papers/jl17-449-78.pdfT1->S0 phoshorescence rate constant is largely distance dependent for the I-…M distance: the rate constant (kPT) will fall of rapidly
with I-..M distance.
Therefore, in case that the Cl…Me interaction in the R-Cl family is HAE in nature one might
expect k
PT to increase mildly, opposite of ourobservation.#7#24kPT = phosphorescence rate constantDkPT = change in phosphorescence rate constant
Slide76https://notendur.hi.is/agust/rannsoknir/papers/pcc3-18-00.pdf Comment along the same lines as the second one in slide 75holds here.https://notendur.hi.is/agust/rannsoknir/papers/saA60-3213-04.pdf#25#22
Slide77https://notendur.hi.is/~agust/rannsoknir/papers/jcp52-2964-70.pdf #19
Slide78Messenger skrif, 210521 (AK<->KEG):Ég er búinn að vera að velta fyrir mér hvernig við getum gert upp á milli hvort "quenching" halogenhaldandi efnanna er vegna 1) "Heavy atom effect" (HAE) halogenanna (Cl, Br) sem lýsir sér í auknum tilfærslulíkum T1 -> S0 vegna blöndunar T1 við S1 og/eða 2) vegna "Energy transfer" fra Me(T1) yfir á Q(T)(?) sem gæti verið mjög mismikið háð virkjunarorku (sbr. fyrri umræða og "energy diagrams"). Ef "HAE" eru ráðandi ættu Q-efnin að hafa svipuð (nema minni) áhrif og I- (frá KI), þ.e. að orsaka ISC, S1 -> T1. Það ætti þá að birtast sem minnkandi flúrljómun en vaxandi fosfórljómun í lausnum án KI með vaxandi styrk á Q. ERGO: það gæti verið ráð að skoða flúrljómun og fosfóljómun fyriir mismikla Q styrki (t.d. fyrir CH2Br2) í lausnum ÁN KI (?)
Slide79#Papers; URLs (…/journal vol-p0-year.pdf) cont. from slide 3Authors; titles27https://notendur.hi.is/agust/rannsoknir/papers/jacs124-10359-02.pdf Christopher J. Fischer,†,‡,§ Ari Gafni,†,| Duncan G. Steel,†,‡,⊥,∇ and Joseph A. Schauerte, The Triplet-State Lifetime of Indole in Aqueous and Viscous Environments: Significance to the Interpretation of Room Temperature Phosphorescence in Proteins28https://notendur.hi.is/agust/rannsoknir/papers/jas74-245-07.pdf N. A. Borisevich and T. F. Raichenok, ABSORPTION, FLUORESCENCE, AND FLUORESCENCE EXCITATION SPECTRA OF FREE MOLECULES OF INDOLE AND ITS DERIVATIVES 29https://notendur.hi.is/agust/rannsoknir/papers/pac68-2223-96.pdf J. W. VERHOEVEN, GLOSSARY OF TERMS USED IN PHOTOCHEMISTRY (various definitions)30https://notendur.hi.is/~agust/rannsoknir/papers/jcp130-244306-09.pdf Christelle Escure et al., Ab initio study of valence and Rydberg states of CH3Br31https://notendur.hi.is/~agust/rannsoknir/papers/jcp062-848-75.pdf Causley and Russell, Vacuum ultraviolet absorption spectra of the bromomethanes32https://notendur.hi.is/~agust/rannsoknir/papers/cp92-59-85.pdf G.N.A. Van Veen, T. Baller and A.E. De Vries: Photofragmentation
of CH3Br in the A band.33
https://notendur.hi.is/~agust/rannsoknir/papers/jpcA114-9991-10.pdf A. Kvaran et al.:
REMPI
spectra, etc. CH3Br34https://notendur.hi.is/~agust/rannsoknir/papers/jcp130-034304-09.pdf V. Blanchet et al., https://notendur.hi.is/~agust/rannsoknir/papers/jcp130-034304-09.pdf; CH3Br35https://notendur.hi.is/agust/rannsoknir/papers/pccp20-17423-18.pdf Arnar Haflijason, a Pavle Glodic,b Greta Koumarianou, b Peter C. Samartzis *b and A´gu´st Kvaran, Multiphoton Rydberg and valence dynamics of CH3Br probed by mass spectrometry and slice imaging36https://notendur.hi.is/~agust/rannsoknir/papers/pccp21-10391-19.pdf Arnar Haflijason, a Pavle Glodic,b Greta Koumarianou, b Peter C. Samartzis *b and A´gu´st Kvaran, Two-color studies of CH3Br excitation dynamics with MPI and slice imaging37https://notendur.hi.is/~agust/rannsoknir/papers/pccp22-4984-20.pdf Kristján Matthíasson, a Greta Koumarianou, b Meng-Xu Jiang, a Pavle Glodic, b Peter C. Samartzis *b and Ágúst Kvaran, Formation of highly excited iodine atoms from multiphoton excitation of CH3I† 38https://notendur.hi.is/agust/rannsoknir/papers/CH3X/cp331-232-07.pdf S. Eden a,*,1, P. Lima˜o-Vieira a,2, S.V. Hoffmann b , N.J. Mason, VUV spectroscopy of CH3Cl and CH3I 79
Slide80#Papers; URLs (…/journal vol-p0-year.pdf)Authors; titles39https://notendur.hi.is/agust/rannsoknir/papers/cpl500-202-10.pdf Giovanni Granucci a,⇑ , Gregory Medders b , Ana Maria Velasco, Potential energy surfaces of the first three singlet states of CH3Cl 40https://notendur.hi.is/~agust/rannsoknir/papers/jcp121-5761-04.pdf D. Ajitha,a) M. Wierzbowska, R. Lindh, and P. A. Malmqvist, Spin–orbit ab initio study of alkyl halide dissociation via electronic curve crossing41https://notendur.hi.is/~agust/rannsoknir/papers/pcpb85-848-09.pdf Carmen Alvarez-Lorenzo*1 , Lev Bromberg2 and Angel Concheiro, Light-sensitive Intelligent Drug Delivery Systems 42https://notendur.hi.is/~agust/rannsoknir/papers/pcpb80-462-04.pdf Giovanni B. Strambini*’, Bruce A. Kerwin’, Bruce D. Mason2 and Margherita Gonnelli’, The Triplet-state Lifetime of lndole Derivatives in Aqueous Solution42https://notendur.hi.is/~agust/rannsoknir/papers/jacs117-7646-95.pdf Giovanni B. Strambini* and Margherita Gonnelli , Tryptophan Phosphorescence in Fluid Solution
80
Slide8181https://notendur.hi.is/agust/rannsoknir/papers/jacs124-10359-02.pdf; #27 1-methylindole (1- MI)https://notendur.hi.is/~agust/rannsoknir/papers/jmstr433-203-98.pdf The numbering system for the indol unit:Polymethyl methacrylate (PMMA)
Slide82https://notendur.hi.is/agust/rannsoknir/papers/jas74-245-07.pdf #28217.4nm263.2nm
Slide83https://notendur.hi.is/agust/rannsoknir/KGE/28-05-21-spectra.pxp ; Gr5Messenger (AK _ KEG), 210528:flúrljómun sem myndast í kjölfar 220 nm örvunar er að minnka og breytast talsvert við að bæta KI út í:sem bendir til að I- aförvi S2.Líklegast er að það gerist með HAE, sem bendir til að það eigi sér stað ISC (S2 -> T?) ?!Það vaknar spurningin: Hvar er sú fosfórljómun?!
Slide84https://goldbook.iupac.org/terms/view/H02756 :file:///C:/Users/agust/Downloads/H02756.pdf
Slide85-
.
.
..*:*hnhttps://chemagic.org/molecules/amini.html#
Graphical
abstract
(?):
….
Slide86E/ cm-11.2M KI, x3I (Abs.)T1S1I-290 nm
I(fl.)
S
1
-> S0https://notendur.hi.is/agust/rannsoknir/KGE/Q spectra-3.pxp ; Gr:13https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; S0327 nm395 nm
50
40
30
20
10
0
Slide87https://notendur.hi.is/agust/rannsoknir/KGE/Q spectra-4.pxp ; Gr:13E/ cm-11.2M KI, x5I(Abs.)T1I(ph.)S1
I
-
https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx
; sheet: „Energetics“290 nm457 nm355 nm
https://notendur.hi.is/agust/rannsoknir/KGE/absorbance_11-05-21KEG.pxp
;Gr3 (
expanded
spectrum
)
S
0
50
40
30
20
10
0
Slide88x 10https://notendur.hi.is/agust/rannsoknir/KGE/absorbance-MEL_10-4-i-buffer.pxp ; Lay0,Gr0
Slide89CH2Cl2CHCl3CCl4S1 (Q, min)S1(Q,min)TI(Abs.)Q =E/ cm-1
S
0
S
0S0S0S2(Me)https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra-3.pxp ; Lay0, Gr:12https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Energetics“S1(Me)S1(Q,min)290 nmS
T
S
1.2M KI, x5
T
S
T
1
(Me)
a)
Slide90CH2Cl2CHCl3CCl4S1 (Q, min)S1(Q,min)TI(Abs.)Q =E/ cm-1
S
0
S
0S0S0S2(Me)https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra-3.pxp ; Lay0, Gr:12https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Energetics“S1(Me)S1(Q,min)290 nmS1.2M KI, x5
T
1
(Me)
a)
T
S
T
S
……………………………..
R-Cl
dissociation
………………………………
Slide91http://butane.chem.uiuc.edu/cyerkes/Chem104ACSpring2009/Genchemref/bondenergies.html
Slide92CH2Br2CHBr3S1(Q,min)S1(Q,min)TQ =S2(Me)https://notendur.hi.is/agust/rannsoknir/KGE/Q%20spectra-1a.pxp ; Lay0, Gr:12https://notendur.hi.is/agust/rannsoknir/KGE/IE-Me.xlsx; sheet: „Energetics“
S
0
S
0S0SI(Abs.)290 nm1.2M KI, x5S1(Me)T1(Me)b) E/ cm-1
T
S
…………..…..
R-Br
dissociation
…………….
Slide93https://notendur.hi.is/~agust/rannsoknir/papers/pcpb85-848-09.pdf
Slide941/t0 = 0.004 =>t0= 250 micros.1/t0 = 0.0093 <=t0= 107 micros.Ca. 1.2Mhttps://notendur.hi.is/agust/rannsoknir/papers/sapA63-337-06.pdf =>