• Current Photovoltaic Research
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• v.8 no.3
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• pp.102-106
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• 2020

In this paper, the effect of MoSe₂ on the contact resistance (R_C) of the transparent conducting oxide (TCO) and Mo junction in the scribed P2 region of the Cu(In,Ga)Se₂ (CIGS) solar module was analyzed. The CIGS/Mo junction becomes ohmic-contact by MoSe₂, so the formation of the MoSe₂ layer is essential. However, the CIGS solar module has a TCO/MoSe₂/Mo junction in the P2 region due to structural differences from the cell. The contact resistance (R_C) of the P2 region was calculated using the transmission line method, and MoSe₂ was confirmed to increase R_C of the TCO/Mo junction. B doped ZnO (BZO) was used as TCO, and when BZO/MoSe₂ junction was formed, conduction band offset (CBO) of 0.6 eV was generated due to the difference in their electron affinities. It is expected that this CBO acts as a carrier transport barrier that disturbs the flow of current, resulting in increased R_C. In order to reduce the R_C caused by CBO, MoSe₂ must be made thin in a CIGS solar module.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.7
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• pp.1647-1652
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• 2010

A CdS film has been used as a window layer in CdTe and Cu(In,Ga)$Se_2$ thin films solar cell. Partial substitution of Zn for Cd increases the photocurrent and the open-circuit voltage by providing a match in the electron affinities of the two materials and the higher band gap. In this paper, CdZnS/CdTe and CdS/CdTe heterojunctions were fabricated and the electrical characteristics were investigated. Current-voltage-temperature measurements showed that the current transport for CdS/CdTe heterojunction was controlled by both tunneling and interface recombination. However, CdZnS/CdTe heterojunction displayed different current transport mechanism with the operating temperature. For above room temperature, the current transport of device was generation/recombination in the depletion region and was the leakage current and/or tunneling in the range below room temperature.

• Journal of the Korean Applied Science and Technology
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• v.17 no.2
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• pp.120-125
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• 2000

The tfTZ(4,4',4''-trifluoro-triazine) was used as a hole blocking material for the electroluminescent devices(ELDs) in this study. In general, the holes are outnumbered the electrons in hole transport and emitting layers because the hole transport is more efficient in most organic ELDs. The hole blocking layer are expected to control the excess holes to increase the recombination of holes and electrons and to decrease current density. The former study using the 2,4,6-triphenyl-1,3,5-triazine(TTA) as hole blocking layer showed that the TTA did not form stable films with vapor deposition technique. The tfTZ can generate stable evaporated films, moreover the fluorine group can lower the highest occupied molecular orbital(HOMO) level, which produces the energy barrier for the holes. The tfTZ has high electron affinities according to the data by the Cyclic-Voltammety(CV) method, which is developed for the measurement of HOMO and lowest occupied molecular orbital(LUMO) level of organic thin films. The lowered HOMO level is made the tfTZ to be applied for a hole blocking layer in ELDs. We fabricated multilayer ELDs with a structure of ITO/hole blocking layer(HBL)/hole transporting layer(HTL)/emitting layer/electrode. The hole blocking properties of this devices is confirmed from the lowered current density values compared with that without hole blocking layer.

• Korean Journal of Veterinary Service
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• v.44 no.4
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• pp.185-194
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• 2021

Polyglutamine extension in the coding sequence of mutant huntingtin causes neuronal degeneration associated with the formation of insoluble polyglutamine aggregates in Huntington's disease (HD). Mutant huntingtin can form aggregates within the nucleus and processes of neurons possibly due to misfolding of the proteins. To better understand the mechanism by which an elongated polyglutamine causes aggregates, we have developed an in vitro binding assay system of polyglutamine tract from truncated huntingtin. We made GST-HD exon1 fusion proteins which have expanded polyglutamine epitopes (e.g., 17, 23, 32, 46, 60, 78, 81, and 94 CAG repeats). In the present emergence of new study adjusted nanotechnology on protein chip such as surface plasmon resonance strategy which used to determine the substance which protein binds in drug discovery platform is worth to understand better neurodegenerative diseases (i.e., Alzheimer disease, Parkinson disease and Huntington disease) and its pathogenesis along with development of therapeutic measures. Hence, we used strengths of surface plasmon resonance (SPR) technology which is enabled to examine binding specificity and explore targeted molecular epitope using its electron charged wave pattern in HD pathogenesis utilize conjugated mutant epitope of HD protein and its interaction whether wild type GST-HD interacts with mutant GST-HD with maximum binding affinity at pH 6.85. We found that the maximum binding affinity of GST-HD17 with GST-HD81 was higher than the binding affinities of GST-HD17 with other mutant GST-HD constructs. Furthermore, our finding illustrated that the mutant form of GST-HD60 showed a stronger binding to GST-HD23 or GST-HD17 than GST-HD60 or GST-HD81. These results indicate that the binding affinity of mutant huntingtin does not correlate with the length of polyglutamine. It suggests that the aggregation of an expanded polyglutamine might have easily occurred in the presence of wild type form of huntingtin.

• Journal of fish pathology
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• v.13 no.2
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• pp.129-136
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• 2000

To understand host-defence mechanism of clam(Ruditapes philippinarum) hemocyte against foreign materials, classification and their seasonal change in the number were performed. clams collected from a farm in Julpo Bay, Gochang, Chollabuk-Do were used in this experiment. Lots of hemocytes were found between the muscle fibers and connetive tissue of posterior adductor muscle. Hemocytes of R. philippinarum were classified into granulocytes and agranulocytes. Granulocytes were composed of three types, basophilic granulocyte, acidophilic granulocyte and fibrocyte in accordance with the staining affinities of their cytoplasmic granules. Fibrocyte has filopodia and vesicle in endoplasm and bigger than other granulocytes in size. Agranulocytes were less in the number and smaller in the size compared to those of granulocytes. Hyalinocytes had no granule in their cytoplasm. The nucleus located in the center of the cell was oval or spherical shaped. In electron microscopic observation, granulocytes and hyalinocytes contained electron-dense vesicles and some small lucid vesicles in their cytoplasm, respectively. Granulocytes phagocytosed more zymosan particles than hyalinocytes. Acidophilic granulocytes showed higher phagocytic ratio than basophilic granulocytes. Total hemocyte numbers showed the highest at April to August and the lowest at October to December. In the composition of each hemocyte, basophilic granulocytes were always more than acidophilic granulocytes and hyalinocytes.

• Economic and Environmental Geology
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• v.50 no.3
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• pp.215-224
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• 2017

Arsenic (As) is known to be the most toxic element and frequently detected in groundwater environment. Inorganic As exists as arsenite [As(III)] and arsenate [As(V)] in reduced and oxidized environments, respectively. It has been reported that the toxicity of arsenite is much higher than that of arsenate and furthermore arsenite shows relatively higher mobility in aqueous environments. For this reason, there have been numerous researches on the process for oxidation of arsenite to arsenate to reduce the toxicity of arsenic. In particular, photooxidation has been considered to be simple, economical, and efficient to attain such goal. This study was conducted to evaluate the applicability of naturally-occurring goethite as a photocatalyst to substitute for $TiO_2$ which has been mostly used in the photooxidation processes so far. In addition, the effects of several factors on the overall performance of arsenite photocatalytic oxidation process were evaluated. The results show that the efficiency of the process was affected by total concentration of dissolved cations rather than by the kind of those cations and also the relatively higher pH conditions seemed to be more favorable to the process. In the case of coexistence of arsenite and arsenate, the removal tendency by adsorption onto goethite appeared to be different between arsenite and arsenate due to their different affinities with goethite, but any effect on the photocatalytic oxidation of arsenite was not observed. In terms of effect of humic acid on the process, it is likely that the higher concentration of humic acid reduced the overall performance of the arsenite photocatalytic oxidation as a result of competing interaction of activated oxygen species, such as hydroxyl and superoxide radicals, with arsenite and humic acid. In addition, it is revealed that the injection of oxygen gas improved the process because oxygen contributes to arsenite oxidation as an electron acceptor. Based on the results of the study, consequently, the photocatalytic oxidation of aqueous arsenite using goethite seems to be greatly feasible with the optimization of process.