수소에너지는 환경오염과 화석에너지 고갈에 따른 에너지 문제를 해결할 수 있는 유력한 대안으로 주목받고 있다. 수소에너지 시대 개막을 위한 준비는 아직 걸음마 단계이나 정부의 지속적이며 전폭적인 정책적 재정적 지원과 더불어 각 분야의 연구 기술개발 활성화 노력을 통해 조속한 시일 내에 실현될 것으로 예상된다. 세계 무역의 견인차 역할을 맡고 있는 선박에 수소에너지 기술을 도입하고 활용하기 위한 준비와 연구가 절실하다. 일각의 수소 연료전지선박에 관한 연구와 실증이 활발히 진행 중인 사실은 고무적이다. 이와 함께 보다 대형화되는 선박과 해상의 특수한 환경 속에서 수소에너지를 직접 이용해 항행에 필요한 동력을 얻을 수 있는 수소엔진과 같은 다양한 방법에 관한 연구도 병행되어야 할 것으로 판단된다.

IS (요오드-황)프로세스의 HI 분해반응 공정에서의 적용을 목적으로 지르코니아 코팅 지지체를 이용하여 CVD법에 의해 수소분리막을 제작하였으며, 분리막으로서의 가능성을 평가하였다. 제작한 막의 형상 및 Si의 분포를 파악하기 위해 SEM 및 EPMA를 이용하여 분석하였다. 지르코니아를 코팅한 지지체를 이용하여 제작한 막에 Zr-Si-O층이 존재한다는 것을 알 수 있었다. 제작한 막의 수소와 질소가스의 단일 성분 투과속도를 300~600℃에서 측정하였다. 600℃에서 Z-1막에서의 수소투과속도는 1 × 10 -7 mol·Pa -1·m -2·s -1를 나타냈다. 질소에 대한 수소의 선택성은 Z-1 막에서 5.0, Z-2막에서 5.75를 나타냈다.

Most wastewater treatment plants are facing odor and sludge disposal problems. In this lab-scale study, odor and sludge from wastewater treatment processes were treated using a combined non-thermal plasma and sludge reactor. The hydrogen sulfide concentration introduced to the reactor was varied at 10, 20, and 50 ppm, and its removal efficiency and system performance were determined. Ozone was produced by the plasma reaction at a concentration of 200 ppm under the given condition. 80% of the hydrogen sulfide was removed regardless of its introduced concentration. In addition, due to the ozone carried over to the sludge reactor, the organic constituents in the waste sludge in terms of TCOD decreased by 30%. The ion concentrations of HS- and SO₄²⁻ in the sludge increased during the four hour experimental period. As a result, the plasma oxidation system can treat waste sludge effectively for the simultaneous reduction of sludge volume and odor.

This study is focused on the channel design of bipolar plate in the electrode of hydrogen gas generator. The characteristics of hydrogen gas generation was studied in view of efficiency of hydrogen gas generation rate and a tendency of gas flow through the riv design of electrode. Since the flow rate of generated gas is the most crucial in determining the efficiency of hydrogen gas generator, we adopted the commercial analytical program of COMSOL MultiphysicsTM to calculate the theoretical flow rate of hydrogen gas from the outlet of gas generator.

In this study, we attempted to evaluate the relationship between dilution‐to‐threshold (D/T) ratio derived by air dilution sensory (ADS) test and the concentration levels of both individual odorant (using H₂S and acetaldehyde (AA)) and their mixture. For the purpose of our comparative study, we prepared both standard gases of two individual compounds and their mixture at 9 concentration levels. Each of all these samples were analyzed by ADS test, and the results were analyzed in relation to their odor intensity. The results of individual odorant samples showed the two contrasting characteristics of each individual compound. H2S generally showed sensitive detection at low concentration but less sensitive detection with increasing concentration. In contrast, AA showed fairly contrasting trend with slow increasing sensitivity. When the D/T ratios estimated from individual samples were used to predict those of mixed samples, the results were reflecting the mixed effects of the basic characteristics owned by each individual compound. As the lower and upper odor intensities of mixed samples were best reflected by AA and H2S, respectively, the D/T ratio of mixed samples complied with the larger D/T values of each compound at a given odor intensity.

Bismuth-telluride based thermoelectric powders were fabricated by two-step planetary milling process which produces bimodal size distribution ranging . The powders were reduced in hydrogen atmosphere to minimize oxygen contents which cause degradation of thermoelectric performance by decreasing electrical conductivity. Oxygen contents were decreased from 0.48% to 0.25% by the reduction process. In this study, both the as-synthesized and the reduced powders were consolidated by the spark plasma sintering process at for 10 min at the heating rate of and then their thermoelectric properties were investigated. The sintered samples using the reduced p-type thermoelectric powders show 15% lower specific electrical resistivity () than those of the as-synthesized powders while Seebeck coefficient and thermal conductivity do not change a lot. The results confirmed that ZT value of thermoelectric performance at room temperature was improved by 15% due to high electric conductivity caused by the controlled oxygen contents present at bismuth telluride materials.

수소투과금속인 tantalum과 세라믹 지지체로 Y2O3-stabilized ZrO2 (YSZ)를 이용하여 cermet 수소분리막을 제조하였다. Ta/YSZ cermet 분리막은 헬륨분위기에서의 예비소결과 고진공 하에서의 본소결을 통해 제조하였으며, 소결 및 밀봉 과정에서 발생하는 불순물은 연마를 통해 제거 가능하였다. 이렇게 제조된 분리막은 tantalum의 연속상이 잘 발달된 치밀구조를 보였다. 수소 해리를 위해 팔라듐 코팅을 한 Ta/YSZ 분리막을 이용하여 200∼350°C의 범위에서 수소투과실험을 수행하였다. 300°C에서 분리막에 균열이 형성되었고 Pd 코팅층은 몇 곳이 박리되었다. XRD 결과는 tantalum이 수소와 반응하여 Ta2H가 생성되는 것을 보여주며, Ta2H에 인한 격자 팽창이 분리막의 결함을 초래하였다.

Cermet 분리막 제조를 위한 혼합 분말은 60 vol.% vanadium과 Y2O3-stabilized ZrO2 (YSZ)를 기계적으로 혼합하여 준비하였다. 혼합 분말을 원판으로 압축한 후 진공 분위기에서 1600°C로 2시간동안 소결하였다. 소결 분리막은 치밀하였고, 브레이징 필러를 이용하여 스테인레스 링에 장착되었다. V/YSZ 분리막의 수소 투과량은 100% 수소를 흘려 200∼ 350°C 범위에서 측정되었다. 350°C, 0.5 bar압력에서 분리막의 양 표면에 균열이 형성되었다. 투과실험 동안에 V/YSZ 분리막의 vanadium은 수소와 반응하여 V2H를 생성하였으며, 이로 인해 분리막이 균열되는 것을 알 수 있었다.

This study is focused on the modeling of two phase fluid flow system in the electrode of hydrogen gas generator. The characteristics of hydrogen gas generation was studied in view of efficiency of hydrogen gas generation rate and a tendency of gas flow through the riv of electrode. Since the flow rate of generated gas is the most crucial in determining the efficiency of hydrogen gas generator, we adopted the commercial analytical program of COMSOL MultiphysicsTM to calculate the theoretical flow rate of hydrogen gas from the outlet of gas generator.

The conception rate of cow is a major factor in farm management. The environment of farm and management of cow are the best influencing factors on conception rate, and the fertility of bull is the second influencing factor. In Hanwoo bull, however, the informations limited to performance and carcass traits have been offered to Hanwoo farmer. Therefore, this study analysed the estimated relative conception rates (ERCR) for estimation of fertility of bulls, using the 8,892 mating data with 116 heads of prove bull to produce progeny. Mean of least square means of conception rate after first insemination was 50.95% in bull herds. On the standard of this mean, ERCRs after first insemination of each bull were analysed. Values ranged from -26.1% to +21.0%, the difference was 47.1%. Among 116 heads of bull analysed, KPN582 showed the highest ERCR as 21.0%, KPN550 (18.3%), KPN656 (16.7%), KPN632 (15.8%), KPN690 (14.9%) were gone behind, but KPN621 was the lowest as -26.1%, KPN680 (-21.3%), KPN674 (-16.2%), KPN569 (-15.9%), KPN699 (-14.9%) were succeeded. If ERCRs of Hanwoo bull will be offered to Hanwoo farmer, it will be worthwhile.

The relationships of scrotal circumference (SC) to semen characteristics and the conception rate (70 days-nonreturn rate) of artificial insemination in farm were studied with 137 heads of bull in Hanwoo. The average and range of SC were cm and 26.0~52.5 cm, respectively. Hanwoo bulls were classified with SC, divided into 34 cm below group, 34~39 cm group, and 39 cm over group. The 5,487 semen records of 43 heads of bull from July. 1. 2007 to June. 30. 2008. were used to determine the relationships between SC and semen characteristics. The semen concentration and total sperm number of each group were 11.18, 16.68, and , and 69.83, 101.64 and /ejaculate. The bulls with 34 cm or more SC were higher than the bulls with 34 cm below in semen concentration and total sperm number (p<0.01). But between SC and semen volume have no significant relationship (p>0.05). The 9,862 mating records of 44 farm with 137 heads of bull were used to determine the relationships between SC and conception rate. The conception rate of 1st artificial insemination were 73.31, 74.16, and 77.33 % in each group. Also SC was positively correlated with pregnancy rate (r=0.12, p=0.17). These results indicate that SC correlates positively with semen characteristics, and maybe with pregnancy rate in Hanwoo.