• Current Photovoltaic Research
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• v.1 no.2
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• pp.82-89
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• 2013

$Cu_2ZnSnS_4$ thin film have been fabricated by rapid thermal annealing of dc-sputtered metal precursor with Cu/ZnSn/Cu stack in sulfur ambient. A CZTS film with a good uniformity was formed at $560^{\circ}C$ in 6 min. $Cu_2SnS_3$ and $Cu_3SnS_4$ secondary phases were present at $540^{\circ}C$ and a trace amount of $Cu_2SnS_3$ secondary phase was present at $560^{\circ}C$. Single-phase large-grained CZTS film with rough surface was formed at $560^{\circ}C$. Solar cell with best efficiency of 4.7% ($V_{oc}=632mV$, $j_{sc}=15.8mA/cm^2$, FF = 47.13%) for an area of $0.44cm^2$ was obtained for the CZTS absorber grown at $560^{\circ}C$ for 6 min. The existence of second phase at lower-temperature annealing and rough surface at higher-temperature annealing caused the degradation of cell performance. Also poor back contact by void formation deteriorated cell performance. The fill factor was below 0.5; it should be increased by minimizing voids at the CZTS/Mo interface. Our results suggest that CZTS absorbers can be grown by rapid thermal annealing of metallic precursors in sulfur ambient for short process times ranging in minutes.

• Korean Journal of Pharmacognosy
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• v.17 no.3
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• pp.248-254
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• 1986

Effects of vinblastine(VLB) and vincristine(VCR) on cell-mediated immunity(CMI) were studied with the microcytotoxicity test(MCT) after normal or pre-sensitized Balb/c mice had been treated in vivo with a combination of two different doses of VLB or VCR(single dose of 20% and 60% $LD_{50}$, i.p.) at different times (from day -6 to day +4) plus allo-transplantation antigen(allo-TA, cells from C3H mice at day 0). The results were that $LD_{50}$ of VLB for female Balb/c mouse was 7.3mg/kg body weight (i.p.) and $LD_{50}$ of VCR was 4.3mg/kg body weight and that VLB and VCR acted as immunosuppressive agents on the primary CMI when administered after allo-TA(antigen-drug-phase), but showed no effect when administered prior to allo-TA(drug-antigen-phase). Change of doses of VLB and VCR(20% $LD_{50}$, 60% $LD_{50}$) caused quantitative or qualitative variations in the immunomodulating effects of these two drugs. Neither VLB nor VCR had any immunomodulating effect on the secondary CMI. Lastly, the results support that the four parameters (type of drug, sensitization status, time of drug treatment in relation to antigen injection, and drug dosis) are significant for the effects of the VLB and VCR on the CMI, and that VLB and VCR may inhibit the proliferation of antigen-stimulated T effector lymphocytes but not memory-cytotoxic T lymphocytes.

• Current Photovoltaic Research
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• v.2 no.3
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• pp.120-123
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• 2014

Thermal doping method using furnace is generally used for solar-cell wafer doping. It takes a lot of time and high cost and use toxic gas. Generally selective emitter doping using laser, but laser is very high equipment and induce the wafer's structure damage. In this study, we apply atmospheric pressure plasma for solar-cell wafer doping. We fabricated that the atmospheric pressure plasma jet injected Ar gas is inputted a low frequency (1 kHz ~ 100 kHz). We used shallow doping wafers existing PSG (Phosphorus Silicate Glass) on the shallow doping CZ P-type wafer (120 ohm/square). SIMS (Secondary Ion Mass Spectroscopy) are used for measuring wafer doping depth and concentration of phosphorus. We check that wafer's surface is not changed after plasma doping and atmospheric pressure doping width is broaden by increase of plasma treatment time and current.

• Journal of the Korean Ceramic Society
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• v.53 no.5
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• pp.506-510
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• 2016

The eutectic melt of BaO-CuO flux is known to be a potential sintering aid for $Ba(Zr,Y)O_3$ (BZY) electrolyte for proton-conducting ceramic fuel cells (PCFCs). A density of BZY higher than 97% of theoretical density can be achieved via sintering at $1300^{\circ}C$ for 2 h using a flux composed of 28 mol% BaO and 72 mol% CuO. In the present study, chemical and structural evolution of BaO-CuO flux throughout the sintering process was investigated. An intermediate holding step at $1100^{\circ}C$ leads to formation of various impurity compounds such as $BaCuO_{1.977}$, $Ba_{0.92}Cu_{1.06}O_{2.28}$ and $Cu_{16}O_{14.15}$, which exhibit significantly larger unit cell volumes than the matrix. The presence of such secondary compounds with large lattice mismatch can potentially lead to mechanical failure. On the other hand, direct heating to the final sintering temperature produced CuO and $Cu_2O$ as secondary phases, whose unit cell volumes are close to that of the matrix. Therefore, the final composition of the flux is strongly affected by the thermal history, and a proper sintering schedule should be used to obtain the desired properties of the final product.

• Journal of the Korean Electrochemical Society
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• v.25 no.3
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• pp.119-124
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• 2022

Because high power with large size cell is used for the battery pack of hybrid electric vehicles and electric vehicles (HEV and EV), average temperature in a battery cell is the important criteria of the thermal management of the battery pack. Furthermore, fast charging technology is required to reduce battery charging time. Since battery pack performance and lifespan are deteriorated due to the heat of cells and electronic components caused by fast charging, an effective cooling system is required to reduce performance deterioration. In this study, a cooling system and module design applied to a pouch-type for fast charging battery cell are investigated, and the cooling performance that can maximize the efficiency of the battery was analyzed. The result shows that the vapor chamber cooling system has better cooling performance, the temperature drop in the module was 5.82 ℃ compared with aluminum cooling plates.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.3
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• pp.283-291
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• 2023

The physical properties were analyzed for four gas diffusion layers, and gas diffusion electrodes (GDEs) for the cathode of high-temperature polymer electrolyte membrane fuel cell were fabricated through bar coating with three binder to carbon (B/C) ratios. Among them, The GDE from JNT30-A6P showed a significant change in secondary pore volume at a B/C ratio of 0.31, which had the largest pore volume among all GDEs. In the polarization curve, JNT30-A6P GDE showed the best membrane electrode assembly (MEA) performance with a peak power density of 384 mW/cm² at a a B/C ratio of 0.31. From the distribution of relaxation time analysis, the peak 1 corresponding to mass transfer resistance of oxygen reduction reaction (ORR) was significantly reduced in the JNT30-A6P GDE. This is the result that when the binder content decreased, the volume of the secondary pore increased, and the mass transfer resistance of ORR decreased, which played an essential role in the MEA performance.

• Journal of Animal Science and Technology
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• v.65 no.4
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• pp.698-719
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• 2023

Postweaning multisystemic wasting syndrome (PMWS) is caused by a systemic inflammation after porcine circovirus type 2 (PCV2) infection. It was one of the most economically important pathogens affecting pig production worldwide before PCV2 vaccine was first introduced in 2006. After the development of a vaccine against PCV2a type, pig farms gradually restored enormous economic losses from PMWS. However, vaccine against PCV2a type could not be fully effective against several different PCV2 genotypes (PCV2b - PCV2h). In addition, PCV2a vaccine itself could generate antigenic drift of PCV2 capsid. Therefore, PCV2 infection still threats pig industry worldwide. PCV2 infection was initially found in local tissues including reproductive, respiratory, and digestive tracks. However, PCV2 infection often leads to a systemic inflammation which can cause severe immunosuppression by depleting peripheral lymphocytes in secondary lymphoid tissues. Subsequently, a secondary infection with other microorganisms can cause PMWS. Eleven putative open reading frames (ORFs) have been predicted to encode PCV2 genome. Among them, gene products of six ORFs from ORF1 to ORF6 have been identified and characterized to estimate its functional role during PCV2 infection. Acquiring knowledge about the specific interaction between each PCV2 ORF protein and host protein might be a key to develop preventive or therapeutic tools to control PCV2 infection. In this article, we reviewed current understanding of how each ORF of PCV2 manipulates host cell signaling related to immune suppression caused by PCV2.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.862-879
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• 2001

The walls of all higher plants are organized as a cellulosic, fibrillar phase embedded in a matrix phase composed of non-cellulosic polysaccharides, some proteins and, in most secondary walls, lignin. At the effective utilization of plant biomass, qualitative and quantitative analyses of plant cell walls are essential. Structural features of individual components are being clarified using newly developed equipments and techniques. However, "empirical" procedures to elucidate plant cell walls, which are not due to scientific definition of components, are still applied in some fields. These procedures may give misunderstanding for the effective utilization of plant biomass. In addition, interesting the investigation of wall organization is moving towards not only qualitatively characterisation, but also quantitation of the associations between wall components. These involve polysaccharide-polysaccharide and polysaccharide-lignin cross-links. Investigation of the associations is being done in order to understand the chemical structure, organization and biosynthesis of the cell wall and physiology of the plants. Procedures for qualitative and quantitative analyses based on the definition of cell wall components are reviewed focussing in nutritional elucidation of forage grasses by ruminant microorganisms.

• The Transactions of the Korean Institute of Power Electronics
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• v.18 no.1
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• pp.1-9
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• 2013

This paper proposes a ST(Switched Trans) quasi Z-source inverter using a Switched Trans Cell combing the characteristics of a Switched Inductor Cell and Trans. A DC link inductor of the conventional quasi Z-source inverter is alternated with Switched Trans Cell of the proposed ST quasi Z-source inverter. Trans Cell of the proposed method consists of one Trans and two diodes, and the proposed method has higher and more various boost function than the conventional quasi Z-source inverter by simply changing the turns ratio of primary and secondary of the Trans. The validity of the proposed ST Z-source inverter was confirmed by PSIM simulation and a DSP based experiment under the input voltage 48V and output phase voltage 30V. As a result, when compared with the traditional quasi Z-source inverter, the proposed method has the advantage of the low voltage stress under the same output voltage condition of the voltage.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.2
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• pp.403-409
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• 2008

In Oriental medicine daeseungki-tang is one of the prescription that is used clinically for constipation of paralytics. The objective of the study was to observe the effect of daeseungki-tang on apoptotic neuronal cell death. In the present study, middle cerebral artery occlusion(MCAO) rats were treated with daeseungi-tang for 5 days and the edema percentage of cerebral hemisphere of MCAO rats were investigated primary. Secondary, appearances of Bax, Bcl-2,-factors that is related to apoptotic neuronal cell death - and HSP72 in the brain of MCAO rats were investigated via immunohistochemistry. Daeseungki-tang significantly decreased edema percentage of the cerebral hemisphere of MCAO rats. Daeseungki-tang significantly decreased Bax positive cells, but did not change the apperances of Bcl-2 positive cells in the penumbra of the cerebral cortex and the caudoputamen of MCAO rats. Daeseungki-tang significantly decreased HSP72 positive cells in the penumbra of the cerebral cortex, but not in the caudoputamen of MCAO rats. Based on the present results, it can be suggested that treatment with daeseungki-tang may decrease edema of the cerebral hemisphere and restrain apoptotic neuronal cell death in the penumbra of the cerebral cortex.