Spectral Investigations of the Effects of 60Co-Gamma Irradiation on Iodothyronine and Iodotyrosines

1987 ◽  
Vol 41 (1) ◽  
pp. 74-79
Author(s):  
A. Obaid ◽  
S. Basahl ◽  
A. Diefallah ◽  
R. Abu-Eittah
Keyword(s):  
Ir Spectra ◽  
Gamma Irradiation ◽  
Uv Spectra ◽  
Uv And Ir Spectra ◽  
60Co Gamma ◽  
Carbonyl Absorption

Solids of 3-iodo-, 3–5–di-iodotyrosine and 3,5-di-iodothyronine were irradiated by 60Co-gamma irradiation for a period of about twenty hours. The effects of irradiation were investigated through a study of the UV and IR spectra of irradiated samples. UV spectra showed the presence of a new band at 360 nm which was assigned to the formation of IO−. IR spectra showed a strong carbonyl absorption and the removal of the carboxylate band in the case of thyronine only. For comparison, the spectra of the studied compounds were investigated before irradiation.

Interconversion of Nitrenes, Carbenes, and Nitrile Ylides by Ring Expansion, Ring Opening, Ring Contraction, and Ring Closure: 3-Quinolylnitrene, 2-Quinoxalylcarbene, and 3-Quinolylcarbene

2009 ◽  
Vol 62 (3) ◽  
pp. 275 ◽  
Author(s):  
David Kvaskoff ◽  
Ullrich Mitschke ◽  
Chris Addicott ◽  
Justin Finnerty ◽  
Pawel Bednarek ◽  
...  
Keyword(s):  
Ir Spectra ◽  
Ring Opening ◽  
Density Functional ◽  
Diazo Compound ◽  
Density Functional Theory Calculations ◽  
Ring Expansion ◽  
Uv Spectra ◽  
Ring Closure ◽  
High Yield ◽  
Uv And Ir Spectra

Photolysis of 3-azidoquinoline 6 in an Ar matrix generates 3-quinolylnitrene 7, which is characterized by its electron spin resonance (ESR), UV, and IR spectra in Ar matrices. Nitrene 7 undergoes ring opening to a nitrile ylide 19, also characterized by its UV and IR spectra. A subsequent 1,7-hydrogen shift in the ylide 19 affords 3-(2-isocyanophenyl)ketenimine 20. Matrix photolysis of 1,2,3-triazolo[1,5-c]quinoxaline 26 generates 4-diazomethylquinazoline 27, followed by 4-quinazolylcarbene 28, which is characterized by ESR and IR spectroscopy. Further photolysis of carbene 28 slowly generates ketenimine 20, thus suggesting that ylide 19 is formed initially. Flash vacuum thermolysis (FVT) of both 6 and 26 affords 3-cyanoindole 22 in high yield, thereby indicating that carbene 28 and nitrene 7 enter the same energy surface. Matrix photolysis of 3-quinolyldiazomethane 30 generates 3-quinolylcarbene 31, which on photolysis at >500 nm reacts with N2 to regenerate diazo compound 30. Photolysis of 30 in the presence of CO generates a ketene (34). 3-Quinolylcarbene 31 cyclizes on photolysis at >500 nm to 5-aza-2,3-benzobicyclo[4.1.0]hepta-2,4,7-triene 32. Both 31 and 32 are characterized by their IR and UV spectra. FVT of 30 yields a mixture of 2- and 3-cyanoindenes via a carbene–carbene–nitrene rearrangement 31 → 2-quinolylcarbene 39 → 1-naphthylnitrene 43. The reaction mechanisms are supported by density functional theory calculations of the energies and spectra of all relevant ground and transition state structures at the B3LYP/6–31G* level.

Preparation and Research of Polymolybdate/Polymer Composite Membrane by Electrospinning and its Photo-Catalytic Property

2013 ◽  
Vol 395-396 ◽  
pp. 415-418
Author(s):  
Zhi Ming Zhang ◽  
Ting Ting Li ◽  
Ce Liu
Keyword(s):  
Hydrogen Bond ◽  
Ir Spectra ◽  
Composite Membrane ◽  
Phosphomolybdic Acid ◽  
Uv Spectra ◽  
Polarizing Microscopy ◽  
Optimum Parameters ◽  
Anhydrous Alcohol ◽  
Cellulosic Membrane ◽  
Strong Absorption Peak

Composite cellulosic membrane of PMMA and phosphomolybdic acid was prepared by electrospinning. During the progress, the factor of electrospinning and the optimum parameters was found out within the orthogonal combination experiment program. Then the morphology of the composite cellulosic membrane was observed by polarizing microscopy. To resolve PMMA, DMF and anhydrous alcohol were used. When their ratios were 1:1, the diameter of the fibre was the most homogeneous. During the electrospinning, the concentration of PMMA was the most important factor. When the concentrations were less then 10%, there were hardly fibres on the foil. The diameter of the fibre ranged from 0.5 to 1.2 μm along with the increment of the concentration of PMMA. The addition of phosphomolybdic acid made the diameter of the fibre decrease. IR-spectra showed that phosphomolybdic acid kept its Keggin structure, and it interacted with PMMA through hydrogen bond. The composite cellulosic membrane changed its color when imposed in bright space. UV spectra represented that the composite cellulosic membrane had a strong absorption peak at 700nm.

Effect of 60Co Gamma Irradiation on Storability of Soybean Seed

2006 ◽  
Vol 5 (2) ◽  
pp. 221-225 ◽  
Author(s):  
I.K. Addai . ◽  
O. Safo-Kantanka .
Keyword(s):  
Gamma Irradiation ◽  
Soybean Seed ◽  
60Co Gamma

Dose mapping of the panoramic 60Co gamma irradiation facility at the Ruđer Bošković Institute – Geant4 simulation and measurements

2019 ◽  
Vol 154 ◽  
pp. 108824 ◽  
Author(s):  
Marija Majer ◽  
Matej Roguljić ◽  
Željka Knežević ◽  
Andrey Starodumov ◽  
Dinko Ferenček ◽  
...  
Keyword(s):  
Gamma Irradiation ◽  
Geant4 Simulation ◽  
60Co Gamma ◽  
Dose Mapping

Degradation and Anticarboxylesterase Activity of Disulfoton and Phorate after 60Co Gamma Irradiation

1969 ◽  
Vol 52 (4) ◽  
pp. 805-811
Author(s):  
D L Grant ◽  
C R Sherwood ◽  
K A Mccully
Keyword(s):  
Gamma Radiation ◽  
Gamma Irradiation ◽  
Low Temperatures ◽  
Brilliant Green ◽  
Organophosphorus Pesticides ◽  
Beef Liver ◽  
Oxygen Analog ◽  
60Co Gamma ◽  
Dose Levels

Abstract Disulfoton and phorate were subjected to gamma radiation from 60Co at dose levels of 0, 0.1, 0.5, 1, 2, and 4 Mrad. The inhibition of beef liver carboxylesterases by disulfoton and phorate in vitro was greater with increasing doses of radiation. The degradation of these organophosphorus pesticides was monitored by GLC with electron capture and phosphorus detectors, by TLC with detection by Brilliant green, and by enzyme inhibition with 5-bromoindoxyl acetate as substrate. The pesticides were degraded to the greatest extent in hexane or acetone solution. Less decomposition occurred at low temperatures. The sulfoxide and oxygen analog were present in most irradiated samples. The sulfone, oxygen analog sulfone, and oxygen analog sulfoxide were present in some of the disulfoton and phorate samples which were irradiated with 4 Mrad.

Sintering of Textured YBa2Cu307-x Under Intensive 60Co Gamma Irradiation

1994 ◽  
Vol 354 ◽  
Author(s):  
Elvira M. Ibragimova ◽  
Eldar M. Gasanov ◽  
Makhmud Kalanov ◽  
Marquis A. Kirk ◽  
Ken C. Goretta
Keyword(s):  
Gamma Irradiation ◽  
Dose Rate ◽  
Subsurface Layer ◽  
Gamma Dose ◽  
Ordered Structure ◽  
Sintering Process ◽  
Superconducting Properties ◽  
Oxygen Sublattice ◽  
60Co Gamma ◽  
Sem Analyses

AbstractA study of structural and superconducting characteristics of YBa2Cu307-x ceramics sintered after and in the course of gamma-irradiation is reported. Using X-difraction and SEM analyses and transport measurements, it has been shown that mainly the subsurface layer of crystallites and intergrain contacts are affected by the irradiation by means of sorption/desorption of oxygen and ordering/disordering in oxygen sublattice, which depends on gamma dose rate and dose. The irradiation provides the sintering process with an additional superthermal energy to form the orthorhombic well-ordered structure and to obtain dense ceramics possessing strong intergrain contacts and improved and stable superconducting properties

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