Observation of Carrier Generation in CCD Using Monochromatic Light Irradiation

ABSTRACTIn this work a survey of possible optical stimulation processes in irradiated KCl:Eu with a focusing on photo-transfer thermoluminescence (PTTL) effects are shown. For different wavelengths in the range from 180 to 800 nm a cycle of measurements was performed, each comprising of a TL measurement after light irradiation, a TL measurement after beta irradiation for reference purposes and a PTTL measurement. The latter was obtained by applying first a beta irradiation, then a partial readout up to a certain end temperature followed by a monochromatic light irradiation of a specific wavelength and finally a TL measurement. This procedure was repeated for different partial readout end temperatures. From the results the existence of at least four different photo-transfer processes, induced by 310, 245 and 550 nm light are deduced. The photo transfer process induced by an approximate value of 245 nm produced a TL glow peak not seen before in beta or light induced TL. Furthermore it was observed that some of the TL peaks created by light of 240 and 260 nm were strongly sensitized after a beta irradiation and a partial readout.

Download Full-text

Effects of Monochromatic Light Irradiation by LED on the Internodal Stem Elongation of Seedlings in Eggplant, Leaf Lettuce and Sunflower

Shokubutsu Kankyo Kogaku ◽

10.2525/shita.18.160 ◽

2006 ◽

Vol 18 (2) ◽

pp. 160-166 ◽

Cited By ~ 14

Author(s):

Tadayoshi HIRAI ◽

Wakanori AMAKI ◽

Hiroyuki WATANABE

Keyword(s):

Stem Elongation ◽

Monochromatic Light ◽

Light Irradiation ◽

Leaf Lettuce

Download Full-text

Enhancement of photocatalytic H2 evolution of eosin Y-sensitized reduced graphene oxide through a simple photoreaction

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.5.92 ◽

2014 ◽

Vol 5 ◽

pp. 801-811 ◽

Cited By ~ 31

Author(s):

Weiying Zhang ◽

Yuexiang Li ◽

Shaoqin Peng ◽

Xiang Cai

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Hydrogen Evolution ◽

Irradiation Time ◽

Monochromatic Light ◽

Light Irradiation ◽

Xenon Lamp ◽

Eosin Y ◽

Apparent Quantum Yield ◽

Reduced Graphene

A graphene oxide (GO) solution was irradiated by a Xenon lamp to form reduced graphene oxide (RGO). After irradiation, the epoxy, the carbonyl and the hydroxy groups are gradually removed from GO, resulting in an increase of sp2 π-conjugated domains and defect carbons with holes for the formed RGO. The RGO conductivity increases due to the restoration of sp2 π-conjugated domains. The photocatalytic activity of EY-RGO/Pt for hydrogen evolution was investigated with eosin Y (EY) as a sensitizer of the RGO and Pt as a co-catalyst. When the irradiation time is increased from 0 to 24 h the activity rises, and then reaches a plateau. Under optimum conditions (pH 10.0, 5.0 × 10−4 mol L−1 EY, 10 μg mL−1 RGO), the maximal apparent quantum yield (AQY) of EY-RGO24/Pt for hydrogen evolution rises up to 12.9% under visible light irradiation (λ ≥ 420 nm), and 23.4% under monochromatic light irradiation at 520 nm. Fluorescence spectra and transient absorption decay spectra of the EY-sensitized RGO confirm that the electron transfer ability of RGO increases with increasing irradiation time. The adsorption quantity of EY on the surface of RGO enhances, too. The two factors ultimately result in an enhancement of the photocatalytic hydrogen evolution over EY-RGO/Pt with increasing irradiation time. A possible mechanism is discussed.

Download Full-text

Light-Induced Reactions of Chlorpromazine in the Presence of a Heterogeneous Photocatalyst: Formation of a Long-Lasting Sulfoxide

Catalysts ◽

10.3390/catal9070627 ◽

2019 ◽

Vol 9 (7) ◽

pp. 627 ◽

Cited By ~ 3

Author(s):

Arsou Arimi ◽

Ralf Dillert ◽

Gerald Dräger ◽

Detlef W. Bahnemann

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Irradiation Time ◽

Monochromatic Light ◽

Complete Removal ◽

Heterogeneous Photocatalysis ◽

Light Irradiation ◽

Light Sources ◽

Aerobic Conditions ◽

Conversion Rates

A commercial carbon-modified titanium dioxide, KRONOClean 7000, was applied as a UV(A) and visible-light active photocatalyst to investigate the conversion of the antipsychotic pharmaceutical chlorpromazine in aqueous phase employing two monochromatic light sources emitting at wavelengths of 365 and 455 nm. Photocatalytic and photolytic conversion of chlorpromazine under both anaerobic and aerobic conditions was analyzed using a HPLC-MS technique. Depending on the irradiation wavelength and presence of oxygen, varying conversion rates and intermediates revealing different reaction pathways were observed. Upon visible light irradiation under aerobic conditions, chlorpromazine was only converted in the presence of the photocatalyst. No photocatalytic conversion of this compound under anaerobic conditions upon visible light irradiation was observed. Upon UV(A) irradiation, chlorpromazine was successfully converted into its metabolites in both presence and absence of the photocatalyst. Most importantly, chlorpromazine sulfoxide, a very persistent metabolite of chlorpromazine, was produced throughout the photolytic and photocatalytic conversions of chlorpromazine under aerobic conditions. Chlorpromazine sulfoxide was found to be highly stable under visible light irradiation even in the presence of the photocatalyst. Heterogeneous photocatalysis under UV(A) irradiation resulted in a slow decrease of the sulfoxide concentration, however, the required irradiation time for its complete removal was found to be much longer compared to the removal of chlorpromazine at the same initial concentration.

Download Full-text

Evaluation of the heterostructure ITO/BiVO4 under blue monochromatic light irradiation for photoelectrochemical application

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-019-02827-3 ◽

2020 ◽

Vol 31 (4) ◽

pp. 2833-2844

Author(s):

M. R. da Silva Pelissari ◽

L. V. A. Scalvi ◽

V. S. L. Neto ◽

L. H. Dall’Antonia

Keyword(s):

Monochromatic Light ◽

Light Irradiation

Download Full-text

Sub-Bandgap Light-Induced Carrier Generation at Room Temperature in Silicon Carbide MOS Capacitors

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.441 ◽

2012 ◽

Vol 717-720 ◽

pp. 441-444

Author(s):

Sandeepan DasGupta ◽

Andrew Armstrong ◽

Robert Kaplar ◽

Matthew Marinella ◽

Reinhard Brock ◽

...

Keyword(s):

Electric Fields ◽

Room Temperature ◽

Inversion Layer ◽

Monochromatic Light ◽

Bandgap Energy ◽

Front Side ◽

Carrier Generation ◽

Mos Capacitors ◽

Side Illumination ◽

Metastable Defect

Carrier generation characteristics in n-type substrate SiC MOS capacitors induced by sub-bandgap energy light are reported. The generation rate is high enough to create an inversion layer in ~20 minutes with monochromatic light (front side illumination) of energy 2.1 eV in 4H-SiC for electric fields smaller than 1 MV/cm. Generation and recovery results strongly indicate involvement of a metastable defect whose efficiency as a generation center increases under hole-rich and decreases under electron-rich conditions. The generation dependence on bias history and light energy shows the defect to have properties consistent with the metastable silicon vacancy / carbon vacancy-antisite complex (VSi / Vc - CSi).

Download Full-text

Time-Course Transcriptome Study Reveals Mode of bZIP Transcription Factors on Light Exposure in Arabidopsis

International Journal of Molecular Sciences ◽

10.3390/ijms21061993 ◽

2020 ◽

Vol 21 (6) ◽

pp. 1993 ◽

Cited By ~ 2

Author(s):

Yukio Kurihara ◽

Yuko Makita ◽

Haruka Shimohira ◽

Minami Matsui

Keyword(s):

Gene Expression ◽

Time Course ◽

Target Genes ◽

Light Exposure ◽

Expression Profiles ◽

Red Light ◽

Monochromatic Light ◽

Regulation Of Gene Expression ◽

Light Irradiation

The etiolation process, which occurs after germination, is terminated once light is perceived and then de-etiolation commences. During the de-etiolation period, monochromatic lights (blue, red and far-red) induce differences in gene expression profiles and plant behavior through their respective photoreceptors. ELONGATED HYPOCOTYL 5 (HY5), a bZIP-type transcription factor (TF), regulates gene expression in the de-etiolation process, and other bZIP TFs are also involved in this regulation. However, transcriptomic changes that occur in etiolated seedlings upon monochromatic light irradiation and the relationship with the bZIP TFs still remain to be elucidated. Here, we track changes in the transcriptome after exposure to white, blue, red and far-red light following darkness and reveal both shared and non-shared trends of transcriptomic change between the four kinds of light. Interestingly, after exposure to light, HY5 expression synchronized with those of the related bZIP TF genes, GBF2 and GBF3, rather than HY5 HOMOLOG (HYH). To speculate on the redundancy of target genes between the bZIP TFs, we inspected the genome-wide physical binding sites of homodimers of seven bZIP TFs, HY5, HYH, GBF1, GBF2, GBF3, GBF4 and EEL, using an in vitro binding assay. The results reveal large overlaps of target gene candidates, indicating a complicated regulatory literature among TFs. This work provides novel insight into understanding the regulation of gene expression of the plant response to monochromatic light irradiation.

Download Full-text