• 한국수산과학회지
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• 제10권1호
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• pp.11-15
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• 1977

Brownish discoloration develops very rapidly in the storage of dried oyster. This undesirable browning is mainly caused by the series of reactions of sugar-amino condensation, enzymatic oxidation of tyrosine and/or the oxidative rancidity of lipids in the tissue of oyster. Sulfites are commonly used as inhibitors for Maillard type browning reactions in agricultural products. The inhibitory effect of sulfite treatment on canned oysters was also confirmed in some investigations. The results suggested that sulfites not only work on blocking tile amadori rearrangement but also on the reduction of free tyrosine which retards the progress of enzymatic oxidation of tyrosine tyrosinase. In this paper, the effect of sodium sulfite treatment on the reduction of reducing sugar and free tyrosine as a function i)f browning inhibition in oyster was tested and other treatment with glucose-oxidase and yeast were also applied. In preparation of samples, fresh oysters were soaked in sodium sulfite solution by various concentration for different treating times, washed in running water to remove the sulfite residue, and finally dried in the shade. In the result, the treatment of sodium sulfite was certainly effective on the reduction of both free tyrosine and reducing sugars in fresh oyster. The best results were obtained by the treatment of 0.5M sodium sulfite solution for 60 minutes each for soaking and washing. Treatment with, glucose-oxidase and yeast solutions, however, did appear somewhat effective but it required so much time for a certain effect that it seemed not practically applicable.

• 생물환경조절학회지
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• 제16권4호
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• pp.333-337
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• 2007

토양수분 조건 및 송풍처리가 참외 발효과 발생에 미치는 영향을 검토한 결과는 다음과 같다. 토양수분이 과다한 조건(-10kPa)에서 뿌리로부터 수분흡수는 많고 저온다습의 기상조건으로 증산이 억제될 때 흡수된 수분이 삼투압이 낮은 과실부위 특히 당 농도가 높은 태좌부로 이동하여 물찬 참외가 발생하는 것으로 생각된다. 참외 발효과는 신토좌, 엘리트 등 세력이 강한 대목에서 많이 발생하고 세력이 약한 홍토좌 대목에서는 적게 발생하고 자근묘에서는 발생하지 않았다. 과실부위 송풍처리로 신토좌, 엘리트, 홍토좌, 자근묘 등 대목의 종류와 관계없이 발효과가 발생하지 않았다. 과육 및 태좌부의 칼슘함량은 무처리구에 비하여 송풍처리구에서 유의하게 높았으며 acetaldehyde, ethanol, ethylacetate 등 발효산물의 함량도 적었다.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.687-693
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• 2004

Composite membranes with a titania layer were prepared by soaking-rolling method with the titania sol of nanoparticles formed in the sol-gel process and investigated regarding the vapor permeation of various organic mixtures. The support modification was conducted by pressing $SiO_2$ xerogel of 500 nm in particle size under 10 MPa on the surface of a porous stainless steel (SUS) substrate and designed the multi-layered structure by coating the intermediate layer of ${\gamma}-Al_2O_3$. Microstructure of titania membrane was affected by heat-treatment and synthesis conditions of precursor sol, and titania formed at calcination temperature of 300$^{\circ}C$ with sol of [$H^+$]/[TIP]=0.3 possessed surface area of 210 $m^2$/g, average pore size of 1.25 nm. The titania composite membrane showed high $H_2/N_2$ selectivity and water/ethanol selectivity as 25-30 and 50-100, respectively. As a result of vapor permeation for water-alcohol and alcohol-alcohol mixture, titania composite membrane showed water-permselective and molecular-sieve permeation behavior. However, water/methanol selectivity of the membrane was very low because of chemical affinity of permeants for the membrane by similar physicochemical properties of water and methanol.

• 한국자원식물학회지
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• 제19권2호
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• pp.252-258
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• 2006

본 연구는 족제비고사리의 대량번식법을 개발하기 위하여 전엽체의 기내배양 및 기외 포자체 형성의 적정 조건을 구하고자 실시되었다. 기내에서 전엽체 증식은 MS배지의 무기물 조건에서 가장 활발하였고, $NH_4^+:NO_3^-$의 농도비가 10:50mM이고, 2%의 sucrose가 첨가된 배지에서 생장이 향상되었다. 전엽체 생장에 적합한 배지의 pH는 5.8이었으며, 적정 agar 농도는 $0.6{\sim}0.8%$로 조사되었다. 배지에 첨가된 생장조절물질(NA, IAA, 2,4-D, BAP, kinetin 및 2ip)은 대부분 농도가 높아질수록 전엽체의 생장을 더욱 저해하는 것으로 나타났다. 기내에서 증식된 전엽체를 토양 별로 기외이식한 결과, 상토 단용구에서 가장 많은 포자체가 형성되었으며, $GA_3\;100{\mu}M$에서 3시간 동안 침지처리 한 전엽체로부터 포자체의 형성이 현저히 촉진되었다.

• 한국자원식물학회지
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• 제22권3호
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• pp.236-241
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• 2009

Dracocephalum argunense Fischer ex Link (Labiatae) is a perennial herbaceous plant used as valuable materials for ornamentals, honey production, and pharmaceutics. Since seed germination of this species was quite difficult, present studies were conducted to improve the germination rate by subjecting the seeds to various environmental conditions (temperature and light) and treatments (scarification, priming and seed coating). Optimum temperature for adequate germination was 20$^{\circ}C$ though it ranged from 15$^{\circ}C$ to 25$^{\circ}C$, and low temperature treatment improved germination rate. Light was required for higher germination rate in this species. The scarification of seeds resulted in much higher germination, especially by the physical treatment with sandpaper or chemical treatment with sulfuric acid for 30 seconds. Various primers with different concentrations were treated on the seeds and it was demonstrated that low temperature enhanced germination rate, regardless of kinds and concentrations of the primers. Three treatment combinations of the primers, 0.5 mM $GA_{3}$ treated for 48 hours, 0.5 mM IAA for 24 hours, and 1.0 mM IAA for 24 hours, increased the seed germination rate profoundly. Soaking treatment of inorganic salts, $KNO_{3}$ and $KH_{3}PO_{4}$, promoted germination when seeds were subjected to low temperature. Water soluble primers such as sucrose at 0.5 and 3% concentration and solid primer talc powder were effective in enhancing germination rate.

• Composites Research
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• 제30권1호
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• pp.21-25
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• 2017

본 연구에서는 일방향 생분해성 유리섬유(BGF)와 친환경 생분해성 수지인 폴리락트산(PLA)을 이용하여 골절치료용 복합재료 고정판을 제작하고 체액 노출에 따른 고정판의 성능 변화를 확인하고자 $50.0^{\circ}C$ 온도조건으로 설정된 인산완충식염수(PBS)에 제작된 생분해성 고정판을 0~3주 동안 노출시켜 질량 변화를 측정하고 4점 굽힘 실험을 수행하였다. 굽힘 강성, 수분 흡수율, 그리고 질량 감소율과 같은 기계적 특성 변화를 파악하였으며 실험 결과로부터 노출 기간이 증가함에 따라 고정판을 구성하고 있는 생분해성 재료들의 손실로 인해 기계적 물성이 서서히 저하되는 경향을 보이는 것을 확인하였다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.155-155
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• 2017

Surface modifications are commonly utilized to adjust the properties of the titanium and its alloy surface to the specific needs of the medical applications, but there are disadvantages such as poor osteoconductive properties and low adhesion of bone cell to implant surface. In order to improve these disadvantages, changes in surface properties have an important effect on osseointegration during implantation. In this paper we applied new technological method for improving a unique surface modification using the characteristic of an electrolytic Solution. Thus, in the electrolyte containing NaF in Na2SO4, TiO2 nanoporous was uniformly formed, and HAp nanoparticles were electrodeposited around the TiO2 nanopores, but in the electrolyte containing NH4F in (NH4)H2PO4, the coarse protrusions including HAp nano particles were regularly deposited onto the TiO2 barrier layer. The surface characteristics and the distributed elements and have been investigated by EDS analysis, and ultra-fine structure of surface are carried out using FE-SEM. To investigate the behavior of the anion, the analysis of chemical states was performed by XPS, and the narrow spectrums for Ti2P, Ca 2p, and P 2p seems to be almost similar depending on the characteristics of the electrolyte solution respectively. In addition, Ca 2p spectrum could be resolved into two peaks for Ca 2p3/2 and 2p1/2 at 347.4 and 351.3 eV, which are related to hydroxyapatite. And, the P peak can also be deconvoluted into two peaks for P1/2 and P3/2 levels with binding energy 134.2 and 133.4 eV, respectively. From the result of soaking test, the apatite morphologys were well-formed onto the modified surface according to the different conditions.

• 보존과학회지
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• 제29권3호
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• pp.243-247
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• 2013

최대함수율 660%, 전건비중 0.15의 소나무를 대상으로 처리조건에 따른 PEG 침투상태를 알아보고자 하였다. PEG 용매, 함침농도, 함침기간, 함침온도에 따른 중량변화율을 구하고 SEM을 이용하여 목재 세포 내부의 PEG 침투상태를 관찰하였다. 그 결과 PEG의 침투에 용매는 큰 영향을 미치지 않았다. 함침농도는 고농도에서 중량증가율이 높았고, 함침기간은 20일에서 가장 큰 중량증가율을 보였으며, 함침온도에 따른 차이는 거의 나타나지 않았다. 이를 토대로 PEG를 이용한 최대함수율 660%의 소형 수침고목재의 처리 시 20일 정도의 함침기간으로 충분한 PEG 침투효과를 얻을 수 있다는 것을 알 수 있었다.

• 상하수도학회지
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• 제30권3호
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• pp.279-284
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• 2016

Membrane distillation (MD) is the thermally driven water separation process based on the vapor pressure difference across the membrane. In order to increase the water recovery of the conventional RO process, the additional MD-PRO pocess was suggested. In this study, the syntheric RO brine was used as a feed solution of the MD process. Due to the high salinity of the RO brine, the MD membrane could be fouled by the scalants. In order to mitigate the scaling on the MD membrane surface, the pre-treatment process using the column filled by natural zeolite was applied. The roughing filter was installed between the pre-treatment process and MD system in order to prevent possible particulate fouling by the debries of the natural zeolite. Moreover, in order to enhance the CEC of the natural zeolite, the NaCl soaking was conducted. The flux and electronic conductivity were monitored under given experimental conditions. And the membrane morphology and the chemical compositions were analyzed by using the SEM-EDX.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.17-22
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• 2011

There are some degradation factors for amorphous silicon solar cells. Light inducing is one of the factor that explained by Staebler-Wronski effect. Also, hotspot heating could be the reason that makes amorphous silicon solar cell degrade. Hotspot heating is occurred when a solar cell is shaded so this work is investigated into two types of shading condition and how these affect to solar cell differently. Reduced irradiance for whole cell and partially shaded as 0($W/m^2$) while the other part of cell is soaking as 1000($W/m^2$) of irradiance are two conditions that are experimented. The two types of shading show different characteristics of degradations. The result shows that partially shaded cell dropped maximum powerless and slower. Also sudden drop points have shown that should be concerned to decide the number of cells for a string. Otherwise, the current through a shaded cell might flow more than cell's capability. It makes cell and module damaged. This work would help to manufacture modules.