A photoconductivity study in γ-irradiated polyethylene at 77 K

Abstract

TOYOAH KIMURA, YUTAKA UEDA, and YOHICHI HIRAI. Can. J. Chem. 64, 695 (1986).A photoconductivity study was made on y-irradiated low and high density polyethylene using 3-methylpentane, methylene chloride, and hexafluorobenzene as dopants. Electron spin resonance (esr) and optical absorption measurements were made together with photoconductivity. A study was also made for poly(4-methylpentene-1). The process of photocurrent generation is not ascribed totally to photodetrapping of trapped electrons in polyethylene; the process by photodetrapping of trapped electrons dominantly contributes to photocurrent generation in the ir region and may partly contribute in the visible region but not in the uv region. Another process for photocurrent generation other than photodetrapping of trapped electrons exists in the uv and perhaps partly in the visible region. We have tentatively ascribed this process to photodetachent of electrons from carbanions whch are formed by the reaction between radicals and electrons.TOYOAH KIMURA, YUTAKA UEDA et YOHICHI HIRAI. Can. J. Chem. 64, 695 (1986).On a effectut une Ctude de photoconductivitC sur des polyCthylknes de basse et de haute densitC, irradiCs aux rayons y et contenant les substances suivantes comme dopants: mtthyl-3 pentane, chlorure de mCthylkne et hexafluorobenzkne. En plus de la photoconductivitt5, on a aussi effectut des mesures de rpe et d'absorption. On a aussi CtudiC le poly(mCthy1-4-pentkne-1). On n'attribue pas tout le processus de la gCnCration du photocurant au photodCpiCgeage des Clectrons piCgCs dans le polyCthylkne; ce processus de photodCpiCgeage des Clectrons piCgCs contribue d'une faqon dominante a la gCnCration du photocourant dans le region de I'ir et peut aussi contribuer en partie dans la rCgion du visible, mais pas dans la region de l'uv. En plus du photodCpiCgeage des Clectrons piCgCs, un autre processus de gtneration de photocourant existe dans l'uv et peut-Ctre aussi dans le visible. Sur une base priliminaire, on a attribuC ce processus au photodttachement des Clectrons des carbanions qui se foment par la rCaction des radicaux et des Clectrons.[Traduit par la revue]

Measurements of High Density Plasmas after Pulsed Discharges in Liquid Helium

“…These emissions were, however, coinpletely absent in Kimura's spectra of nitrogen ion-impinged cryogenic He gas in this spectral range [13]. Only transitions of atomic He 706.5 nm ( 3~~s -2~)~) and 728.1 nm (~~] S -Z~' P ) occurred in Brooks and Hunt's proton beam irradiated cryogenic He gas [14].…”

Polyethylene Glycol as a Green Medium for the Microwave‐Assisted Synthesis of Guanamines

“…[1] By varying substituents in position 6 of 1,3,5-triazine-2,4-diamines (guanamines), the pharmacological profile of the compounds was tuned from antiparasitic [2] to antiulcer, anti-inflammatory [3] and cardiotonic. [4] Some notable examples include compound 1 (Figure 1) possessing nootropic properties [5] and phosphodiesterase 4 inhibitor Irsogladine [6] approved as a gastric mucosal protectant [7] but also claimed to be effective in models of CNS disorders, such as Parkinson disease. [8] Moreover, Irsogladine demonstrated inhibition of heat shock protein 90 (Hsp90) [9] and anticancer properties in several models.…”

Effect of electron beam radiation on the mechanical and thermal properties of poly(4‐methylpentene‐1)

“…Electron spin resonance (ESR) of y-irradiated PMP showed that photobleachable species are formed in the system. 21 Furthermore, the degradation of the optical clarity of PMP due to exposure to neutron and y-radiation was studied at wavelengths in the range of 0.23-2.0 nm. 22 This study reported that PMP retained its optical clarity to doses up to 100 Mrad which is below the typical values for vessel windows in ignited fusion experiments.…”