The shell of form-finding is most important in design procedure of the cooling tower, because the shape of the shell determines the sensitivity of dynamic behavior of the whole tower against wind excitation. The purpose of the study is the investigation of the influences of the geometric parameters of the cooling tower shell on the structural behavior. As a result, a hyperbolic rotational shell with the small radius overall will yield the shell geometry with a higher first natural frequency and thus a wind-insensitive structure. Linearly and nonlinearly numerical analysis are demonstrated influence of the shell-geometric parameters on structural behaviours. The results of this study may be informative for the form-finding of the cooling tower shell.

Genomic DNAs (gDNAs) were isolated from the hard clam ( , Roding, 1798) populations of Gunsan located in the Yellow Sea of the Korean peninsula. Genetic distances among different individuals of the LSCP (light shell color population) population of the hard clam (lane 1-11), GSCP (grey shell color population) population of the hard clam (lane 12-22) and DSCP (dark shell color population) population of the hard clam (lane 23-33), respectively, were generated using Systat version 10 according to the bandsharing values and similarity matrix. The dendrogram, generated by seven reliable oligonucleotides primers, indicates 3 genetic clusters. LSCP population could be evidently discriminated with the other two populations among three populations. The longest genetic distance (0.801) was found to exist between individuals in the two populations, between individuals' no. 33 of the DSCP population and no. 06 of the LSCP population. The higher fragment sizes (>2,000 bp) are much more observed in the GSCP population. Three hard clam populations can be clearly distinguished, especially, by their morphological characters and PCR-based approach.

다양한 생리활성 기능을 가진 파래 분말을 첨가하여 제조한 만두피의 품질특성을 측정한 결과는 다음과 같다. 호화개시온도는 파래 분말의 첨가량이 증가될수록 점진적으로 증가하는 경향을 보였다. 에서 점도, 에서 15분간 유지한 후의 점도 및 최고점도는 파래 분말의 첨가량이 증가함에 따라 감소하는 것으로 나타났다. 만두피의 색도는 파래 분말 첨가량이 증가할수록 명도(L값), 적색도(a값) 및 황색도(b값)는 대조군이 가장 높게 나타났으며, 각 시료간에

PSC 박스 교량의 시공 중 거동 특성을 고려하기 위하여 뼈대 요소를 이용한 시공단계의 설계가 수행되고 있다. 그러나 PSC 박스 교량 중 곡선 램프교 등의 경우는 교량의 외측 및 내측의 변위 및 응력 값이 현저히 다르다. 따라서 PSC 박스 교량의 텐던량 및 시공 중 긴장력이 외측 및 내측에서 다르게 산정되어야 함에도 불구하고 현실적으로는 계산이 불가능하여 같은 양의 텐던과 부적절한 긴장력을 사용하고 있어 시공 중 항상 안전사고에 노출되고 있다. 이러한 단점을 해결하기 위하여 3차원 해석이 필수적으로 요구 되고 있으며 본 연구에서는 PSC 박스 교량의 해석 기법에 필요한 가정된 변형률 PSC 쉘 요소를 제안하고자 한다. 본 쉘요소에 사용된 콘크리트의 크리프 및 건조수축의 재료 모델은 ACI 코드를 사용하였으며, 이 모델을 이용하여 3차원 시공단계해석을 수행하고 그 결과를 뼈대 요소와 비교하였다.

돔배기 육, 연골 및 껍질의 저장 중 총균, 대장균 및 병원성미생물의 생육에 미치는 chitosan-ascorbate(CA)(0.01%) 및 모려(10 ppm)의 처리효과를 조사하였다. 에서 6일간 저장한 결과 대조구의 경우 총균수는 육, 연골 및 껍질에서는 각각 4.24, 3.81, 2.20 log cycle이 증가하였으나 CA처리구는 육에서는 2.66 log cycle이, 연골에서는 2.37 log cycle이, 껍질에서는 1.24 log c

본 연구는 광학현미경과 전자현미경을 이용하여 소라, Batillus cornutus의 정자형성과정과 정자의 미세구조를 관찰하였다. 소라는 2003년 5월에 전라남도 완도군 연안에서 잠수하여 채집하였다. 실험개체의 크기는 각고 였다. 소라의 정소는 다수의 정자형성소낭으로 구성되며, 이들 소낭 내에는 다양한 발달단계를 가지는 생식세포들이 존재하였다. 태사기의 제 1정모세포에서는 연접사복합체가 관찰되었다. 초기의 정세포에서는 골지체의 출현, 핵질 전자밀도의

This study was performed to investigate the possible uses of waste sludge for the removal of heavy metal ions. The adsorption experiments were conducted with wastes such as sewage treatment sludge, water treatment sludge and oyster shell to evaluate their sorption characteristics. Heavy metals selected were cadmium, copper and lead. In the sorption experiments on the sewage treatment sludge, water treatment sludge, oyster shell and soil, sorption occurred in the beginning and it reached equilibrium after 40 minutes on the oyster shell and 4 hour on the sewage treatment sludge and water treatment sludge. Results of Freundlich isotherms indicated that sewage treatment sludge could be properly used as an adsorbent for heavy metals and sorption strength of heavy metals was in the order of Pb > Cu > Cd. In the influence of pH on the adsorbents, sorption rate was more than 80% in pH 4 and most of heavy metals were adsorbed in pH 9. Adsorption rate of Cd decreased with decreasing pH and then adsorption rate of Cu was lower in soil.

Antimicrobial powder was made by exchanging silver ion on calcined oyster shell. On the purpose of application to water clarifier, ball-type media mixed with antimicrobial powder and 0∼30% white kaoline were made. The sterilization effect, pore size distribution and zeta potential was tested to indicate the condition for the media of water clarifier. From these tests, it was confirmed that this media have an excellent sterilization power on G- and G+ germs. As the concentration of the exchanged silver ion increased, the surface charge density of the anions on the surface of the media also increased. The surface pore size decreased with the concentration of silver ion and 20% more white kaoline ratio.Consequently, mixing ratio of white kaoline would appear to indicate the optimun condition as media have sterilization power.

만두피의 반죽제조에 키토산(시판 키토산 및 제조 키토산) 및 폴리인산, 구아껌, 타피오카 등의 성분 배합비율에 따른 반죽의 물성변화를 알아보고자 하였다. 그 결과는 다음과 같다. 제조된 균류키토산의 수분함량은 6.57∼6.58%, 질소함량은 6.71∼6.91%, 용해도는 99.05∼99.13%, 점도는 2.21∼2.23cps, 아세틸화도는 12.0∼l2.7% 그리고 분자량은 3.01∼3.12Dalton으로써 산처리 온도에 따른 FCs40과 FC

In order to examine the pre-treatment effect of crab shell on Pb2+ removal by crab shell in aqueous solution, acid and alkali pre-treated crab shell were used. Electron microscopy techniques such as TEM (transmission electron microscopy) and SEM (scanning electron microscopy), and EDX (energy dispersive X-ray) and FTIR (Fourier transform infrared) spectrometry techniques were used to investigate the process of Pb2+ removal by acid and alkali pre-treated crab shell. The Pb2+ removal by acid pre-treated crab shell was much lower than that by untreated crab shell because of the decrease of CaCO3 from the crab shell. However, the Pb2+ removal by alkali pre-treated crab shell increased compared to that by untreated crab shell. The results were confirmed by TEM, SEM, EDX and FTIR.

In order to examine the inhibition effect of other heavy metal ions on the removal of heavy metal ions by crab shell in aqueous solution, 10 heavy metal ions (Cr3+, Cd2+, Ni2+, Zn2+, Hg2+, Cu2+, Mn2+, Fe2+, Fe3+, Pb2+) were used as single heavy metal ions and mixed heavy metal ions, respectively. In single heavy metal ions, Pb2+, Cr3+, Cu2+ were well removed by crab shell, however, Cd2+, Ni2+, Zn2+, Mn2+ were not. The heavy metal removal increased as the increase of covalent index (Xm2r), and the relationship classified heavy metal ions as 2 heavy metal groups (Fe3+, Fe2+, Cu2+, Cr3+, Mn2+, Ni2+, Zn2+ group and Pb2+, Hg2+, Cd2+ group). In mixed heavy heavy metal ions, the removals of Fe2+, Fe3+, Pb2+, Cu2+ as 0.49 mmol/g, regardless of the existence of other heavy metal ions, were similar to the result of single heavy metal ions experiment. The removals of Mn2+, Cd2+, Ni2+ decreased as the existence of other heavy metal ions, however, the removal of Zn2+, Cr3+, Hg2+ increased.

자연 생물자원 관리를 위해, 광양만내 인공적으로 폐쇄된 슬라그 적재장내에 서식하는 암컷 피뿔고둥 Rapana venose(Valenciennes)를 대상으로 조직학적, 육안적 관찰에 의해 군성숙도, 성비, 산란빈도, 난낭 산출 및 포란수를 조사하였다. 암컷 개체들의 군성숙도(%)는 각고 7.1~8.0 cm의 경우 51.6%이었고, 9.1 cm 이상인 개체들의 경우는 100%이었다. 개체당 총난낭수 및 난낭내의 평균 난수는 각각 192~382개와 500개

Several effects on Pb2+ removal by crab shell from aqueous solution were investigated. As the increase of initial Pb2+ concentration and decrease of initial crab shell concentration, the time required to reach an equilibrium state and the residual Pb2+ concentration increased. In our experimental ranges, the optimum initial Pb2+ concentration and crab shell concentration were below 103 mg/l and over 0.5 mg/l, respectively. Also, in order to investigate the mechanism of Pb2+ removal by crab shell in aqueous solution, the crab shell was compared with chitosan and chitin on aspects of Pb2+ removal capacity and Pb2+ removal rate. The Pb2+ removal by crab shell was greater than that by chitin and chitosan. The role of chitin was not so great in Pb2+ removal by crab shell. The Pb2+ removal by chitosan was not exactly correlated to the molecular weight of chitosan.

In order to examine the availability and effectiveness of crab shell for the removal of heavy metals in aqueous solution, the crab shell was compared with cation exchange resin (CER), zeolite, granular activated carbon (GAC) and powdered activated carbon (PAC) on aspects of heavy metal removal capacity, rate and efficiency. In the removal of Pb, Cd and Cr, the heavy metal removal capacity of crab shell was higher than those of any other sorbents (CER, zeolite, GAC, PAC), and the order of heavy metal removal capacity was crab shell > CER > zeolite > PAC =～GAC. However, in the removal of Cu, the result of crab shell was slightly lower than that of CER. The initial heavy metal removal rate was affected by the sorts of sorbents and metals. In all heavy metals, the heavy metal removal rate of crab shell was higher than those of any other sorbents. Under the heavy metal concentration of 1.0 mmole/ℓ, the heavy metal removal efficiency of crab shell was maintained as 93∼100 %, which was much higher than those of any other sorbents.

김치의 향미개선 및 게껍질 분말 첨가김치의 부미를 제거하기 위한 향미개선제로서 우골추출물의 첨가효과를 검토하였다 우골추출물은 김치의 숙성중 pH와 산도, 총균수, 젖산균비, Leuconostoc과 Lactobacilli의 수에는 큰 영향을 미치지 못하였으나 산미와 김치냄새를 감소시키고 종합적 맛을 개선시키는 향미 개선제로서의 역할을 하였다. 또 우골추출물(0.03%)을 게껍질분말(1.5%)과 함께 첨가할 경우는 게껍질분말만을 첨가한 경우보다 높은

This study was conducted to use oyster shell as media for biological wastewater treatment. The comparison between the removal efficiencies of the activated sludge and the submerged biofilm process with oyster shell media (5% of reactor volume) for domestic sewage treatment was made. The contaminant removal efficiencies of the submerged process were higher than that of the activated sludge process. And the removal efficiencies of the submerged biofilm process with oyster shell media of 10% and 18% were investigated at various loading rate. The removal efficiencies of 10% were higher than that of the 18% during the experimental period. The effluent concentration from the submerged biofilm process using oyster shell media was prediceted by the Stover-Kincannon model.

콩 유전자형간 상호접목을 통하여 지상부 생육과 콩깍지에 대한 종실건물중 비율에 미치는 영향을 비교 검토하고자, 꼬투리의 비대가 충실한 백운콩과 수원 158호, 꼬투리 크기에 비하여 종실건물축적이 불량한 수집검정콩 강릉재래 및 금릉재래를 공시하여, 자가접목 및 4개 유전자형간 상호접목을 한 후 이식재배시험한 결과를 요약하면 다음과 같다. 1. 지상부의 생육정도와 콩깍지 및 종실건물중은 지상부 유전자형간 유의적인 차이가 인정되었으나, 지하부 유전자형간 차이가 없었다. 2. 백립중 및 꼬투리에 대한 종실건물중 비율도 지상부 유전자형에 의하여 결정되기 때문에, 상대적으로 양분흡수와 밀접한 관련이 있는 지하부 유전자형과는 관계가 적었다. 3. 접목된 개체들의 콩깍지 건물중과 콩깍지에 대한 종실건물 비율은 유의적인 부의 상관관계를 나타내고 있어, 콩깍지 건물중이 클수록 콩깍지에 대한 종실건물 비율이 낮아지는 경향이었다.