A new one series of chiral schiff's base containing benzylidene aniline moieties was synthesized and characterized by IR, 1H NMR. elementary analysis, and polarized optical microscopy(POM). The yield of these synthetic compounds was in the range of 62~67℃. The results showed that most of the synthetic compounds were monotropic liquid crystal and exhibited chiral smectic C(Sc*) liquid crystal phases, and the range of phase transition temperature was to 71.4℃ from 45.0℃.

Recently, as concern about the residual antibiotics in milk increase, the detection methods of residual antibiotics used extensevely at the present time were investigated and compared to their properties and the detection limits of variable antibiotics. At first, comparative tests of the detectable sensitivity of 4 teat organisms, B.cereus, B.subtilis, M.luteus, B. stearothermophilus C-953, were performed by disc assay. As a result, B.stearotleermoph.ilus was the most sensitive strain of all other strains and showed the detect limit of 5-50 ppb for penicillins (PCs). And also, B.subtilis was showed the more effective detection limit, 200-400 ppb, for aminoglycosides (AGs) and M.luteus was showed predominant sensitivity , 50-500 ppb for macrolides(MLs) and B.cereus was the most sensitive strain for tetracyclines (TCs) and showed the detection limit of 100-400 ppb. Therefore, each test strains were showed a different sensitivity in the detection of the different antibiotic families. When the detection limit of disc assay and other methods were compared, TTCmethod was less sensitive than other methods showing 5-50 ppb detectable lebel for PCs. Also, for the detection of other antibiotic families TTC method was showed the worst sensitivity and Delvo and Charm Farm tests were similar to the detectable properties of AGs and MLs. Although disc assay was showed the similar detection limit for PCs with Delvo and Charm Farm, it was more widely effective for the detection of kanamycin, erythromycin, chlortetracycline, doxycycline, verginiamycin and so on than Delvo or Charm Farm. CharmII test was showed the best sensitivity for the most of antibiotics except neomycin and gentamycin. But it was necessary that different tests must be performed to each antibiotic family and so it was regarded that the effectiveness of that method was low.

The ethanol extract from the root bark of Morus alba showed the strongest antimicrobial activity on the growth of almost all the tested microorganisms which were food-borne pathogens and food-related microorganisms. In order to isolate and purify of antimicrobial substance extracted from the root bark of Morus albs, the antimicrobial substance from the ethanol extract which exhibited a strong antimicrobial activity was purified by solvent fractionation, silica gel column chromatography, TLC and HPLC. Among the fractions fractionated by 4 kinds of solvents from the ethanol extract, the antimicrobial activity of ethyl acetate fraction had the strongest antimicrobial activity against B. subtilis. Unknown compounds were isolated from the ethyl acetate fraction by silica gel column chromatography, TLC and HPLC and the compounds showed strong absorbance at 207, 217 and 285 nm, therefore, it was supposed to be a kinds of aromatic compound.

자기소화법에 의한 빵 효모의 extract중 불용성 물질들의 분식화학적인 특성이 연구되었다. 적절한 효모의 배양조건 (호모의 종류, 폐 당밀의 농도, 효소활성 첨가제, 은도, pH)에 따라 효모의 최적 자기소화는 48시간(때로는 2∼3일)을 기준으로 하여 효소반응을 중지한 다음 농축하여 extract를 제품화하고 있다. 효모를 배양할 때 세포벽이나 세포막의 형태변화, 막 분해효소의 활성, 원형질의 분리 등은 효모의 자기소화 조건에서 중요한 인자가 되는데, 48시간 이상의 자기소화로 효모 균체로부터 단백질의 수율이 80% 이상(킬달법 정량) 분해가 가능하다는 연구들이 있으나, ^4) 균체의 세포벽이나 세포내 소기관의 세포막들은 여러 종류의 다당류와 지질로 구성된 proteoglycan의 복합체이기 때문에 자기소화 능력만으로서는 시간이 걸리고 충분히 분해되지 않아서 실제로 이용될 수 있는 효모 균체의 소화율은 상대적으로 낮을 수 밖에 없다. 또한 48시간 이상을 자기소화한다 할지라도 세포벽은 완전히 분해되지 않은체 미세한 분말로 남아있을 뿐만 아니라 부분적으로 파괴된 소기관들의 세포막 등 불용성 부유물질들이 함께 포함되어 있기 때문에 관능검사에 좋지않는 영향을 미칠 수도 있다. 그렇지만 자기소화 시간이 무작정 길어진다는 것도 생산비나 제품의 품질면에서 그리 바람직하지 못하다. 아미노산의 분석결과 효모 균체에는 Glu, Ala, Lys, Asp, Val이 풍부한 단백질이 포함되어 있고, 그들의 이용가치를 높이려면 이미 공업적으로 생산되고 있는 lytic효소들을 사용하면 효과적일 수도 있다. 현재 상품화 되어서 판매되는 세포막의 분해효소들은 5종류가 있다.^12) 첫째 snail-gut액, 둘째 helicase, 셋째 glusulase가 있는데 이것은 효모의 plasma membrane 분리시에 사용되지만 helicase보다 4배나 효과가 크다는 것이다. 넷째 β-glucanase는 Arthrobacter luteus등 몇가지 미생물로 부터 생산되는데 helicase나 glusulase보다는 강력하다는 것이다. 마지막으로 Arthrobacter luteus가 생산하는 zymolyases(miles)가 있는데 이 호소는 β-glucanase의 활성 뿐 아니라 protease의 활성도 함께 가지고 있으나 빵 효모의 세포막 분해활성은 낮다근 것이다. 그밖에 lyticase(Sigma CO.)도 시판되고는 있다. 따라서 자기소화 전단계에서 위에 열거된 lytic효소들을 적절히 사용하여 효모의 세포벽이나 세포막을 미리 연화, 용해시키는 것이 효과적일 것이나 빵 효모에는 작용이 대부분 미약하다고 알려졌으며^13), 이들은 원래 분자생물학적인 기법의 실험을 위하여 개발된 것이므로 소규모의 실험에서나 가능할 것이며^2), 실제로 대형 공장에서는 생산설비가 많이 들게 되고, 또한 실험결과에서 얻어진 자료에서 보는 바와 같이 영양학상으로 그리 중요치 않다고 판단되는 물질들을 힘들게 분해할 필요도 없을 듯하다. 그러나 관능점사에서 간혹 문제점이라도 발생한다면 자기소화 시간을 적절히 늘리던가, 또는 효모 extract가 지닌 구수하면서도 감칠맛을 내게되는 최적 소화조건과 시간대에서 자기소화를 중지하고 농축단계로 접어들기 전단계에서 냉수를 가하여 점도를 낮춘 다음, 실온에서 최소한 회전력이, 3, 000×g 이상 되는 원심분리기로 10분간 원심분리하기나, 여러 형태의 여과장치를 병행하는 방법으로 미분해된 세포벽과 불용성 세포막 성분을 물리적으로 제거한다면 품질개선에 도움이 될 것으로 생각된다.

Various humic substances are widely distributed in natural water body, such as rivers and lakes and cause the yellowish or brownish color to water. The evidence that humic substances are precursors of THMs formation in chlorinated drinking water has been reported m the Jiteratures. For the reason of public health as well as aesthetics, needs for humic substances removal have been increased in the conventional water treatment processes. In this research, the characteristics of aluminium coagulation of humic acids and humic acids were investigated. The optimum pH and coagulants dosage to remove these materials simultaneously by coagulation were alto studied. The results are as followed; 1. UV-254 absorptiometry for measuring the concentration of aquatic humic acids showed good applicability and stable results. 2. The optimal pH range for humic acids removal by aluminium coagulation was 5 to 5.5, however, an increase in aluminium coagulant dosage could enhance the removal rate of humic acids in the wide pH range. 3. Coprecipitation of humic acids in the typical pH range of 6.5 to 8 in water treatment processes may require the sweep coagulation mechanism with the excess aluminium coagulant dosage. 4. Using PAC(poly aluminium chloride) or PASS(poly aluminium silica sulfate) as coagulants was able to expand the operating range for removing humic acids. 5. From the coagulation of humic substances(UV-254) and turbidity at pH range of 5.5 - 6.0 and alum dose of 86 ppm, the removal efficiency of turbidity from the reservoir water was above 90% and that of UV-254 was above 70%. 6. By using the reservoir water, the optimum condition of rapid mixing for simultaneous removal of turbidity and UV-254 absorbance was pH of 5.8 and LAS dose of 86 ppm, in this study.

Dextran(Mw.:500,000)용액의 한외여과에 있어서, 현재 나권형 모듈의 유로형성체로 사용되는 난류촉진물체를 적용하여 실험한 결과, 난류촉진물체의 mesh가 증가할수록 막투과 flux가 향상되었으며, 난류영역에서는 층류영역에 비해 순환유속과 난류촉진물체의 사용에 따른 막투과 flux에 대한 영향이 상대적으로 적었다. 난류촉진물체의 사용에 따른 막투과 flux 향상율은 사용한 membrane의 종류에 따라 층류영역의 경우 최대 112%, 난류영역의 경우 50%에 달하였다. 또한 난류촉진물체를 사용함으로써 한외여과막의 고분자 용질에 대한 배제 성능을 높일 수 있었으며, 이러한 flux 및 배제 성능 증가 등의 효과들은 높은 조작압력차와 낮은 순환유속(농도분극이 상대적으로 심한 영역)에서 더욱 두드러졌다. 그러나, 난류촉진물체의 mesh 수와 순환유속이 증가함에 따라 한외여과 cell 내에서의 압력손실도 증가하였으며, 특히 난류영역에서는 그 영향이 매우 심하였으므로 실제 공정 설계시 순환유속과 압력차 및 난류촉진물체 형태에 따른 압력손실을 반드시 고려해 주어야 함을 알 수 있었다. 물질전달계수 예측을 위한 기존의 물질전달 상관관계식을 농도분극층에서의 고분자 물질의 물성변화를 고려하고 경계층 저항 모델에 근거하여 보정하였는 바, 기존의 관계식에 비해 오차를 줄일 수 있었으며, 이때의 관계식은 다음과 같았다.Nsh}=0.151(NRe})0.199}(NSc})0.22}(NScm})0.197};(625

This research was conducted to obtain the basic information on the cell block phenomenon occuring during early development in vitro of mouse embryos. Early embryos were recovered at 3h post-hGG injection(hph). Various chemicals (EDTA, EGTA, DTPA, MA and PRA) were tested to examine the effects of them on the overcoming the 2-cell block phenomenon. One hundreds M of the chelating agents were added to the M16 medium containing embryos. The treated embryos were worked and transferd to fresh M16 medium after 1, 3, 6 and 12h of treatment. Development was examined at 58 and l2Oph injection, respectively. 44.7~68.9% of the treated embryos developed to 4-cell stages at 58hph. Only 17.6~60.3% of the embyos developed upto blastocyst at l20hph. Whereas control embryos showed slightly lower development in M16 medium alone (38.9~42.4%, 4-cell and 3.8~65.5%, blastocyst). Three mitogenic agents were tested. 51.6~63.8% and 43.4~48.1% of embryos developed up to 2-cell and blastocyst stage, respectively when treated in 5 g PHA-M Imi for 5 min, 1, 3 and 6h subsequently cultured in fresh M16 medium. Control embryos only showed 38.8% for 4cell and 5.9% fo blastocyst at 58 and l2Ohph, respectively. 100M PMA was also beneficial for the 2-cell block. Showing better development them that of control (42.4 vs 57.9~59.4% 4cell and 5.9 vs 25.0~55.6% blastocyst, respectively. However 1M butyric acid was toxic to early embryos, thus arresting further development. These result indicate that either chelating or mitogenic agents could be used to overcome the "in vitro 2-cell block" occuring during early development in vitro of ICR embryosCR embryos

본 실험은 시설오이의 상품성 향상 및 생산성 증대를 위하여 주지형인 만능청장마디오이와 측지형인 사엽오이를 유인방법을 달리하여 재배하였으며 그 결과는 다음과 같다. 1. 유인방법 개선을 위한 오이의 저절위 착과특성을 조사하였던 바, 만능청장마디오이의 경우는 3마디까지, 사엽오이의 경우는 4마디까지가 수량 및 상품성이 불량하여 적과재배하는 것이 효과적이었다. 2. 오이의 유인방법 별 초기생육 및 과실의 개화시 자방중, 곡과도, 생장해석면에서 만능청장마디 오이는 횡유인, 종유인, 사면유인 순으로 좋았고 사엽오이는 횡유인, 사면유인, 종유인 순으로 좋게 나타났다. 3. 오이의 유인방법에 따라 초고별 상대조도와 적산엽면적지수로 본 작물의 수광태세는 만능청장 마디오이에서는 종유인과 횡유인이 사면유인보다 양호하였고 사엽오이는 횡유인, 종유인, 사면유인 순으로 나타났다. 4. 수량 및 품질은 만능청장마디오이와 사엽오이 모두에게 횡유인이 가장 우수하게 나타났다.

In this research, investigations were made on the effect of type and load of organic substrate on phosphorus release. Reactors of three different sizes were operated, being fed on five kinds of organic substrates. The quantitative analyses were made on phosphorus release and substrate utilization under anaerobic condition. The molar ratios of the uptaken organic substrate to the released phosphorus were 0.5 with acetate, 0.6 with glucose, 0.8 with glucose/acetate, and 1.2 with glucose/acids, respectively. The phosphorus release was inhibited at the higher organic load than the normal at stead state. Both acetate and acids/glucose enhanced phosphorus release- as well as uptake-rate, however, the complete phosphorus removal was achieved after the microbial adaptation to the new environment. In case with acetate, operation was hampered by the poor sludge settleability and phosphorus uptake was not enough although the phosphorus release was active. But with milk/starch, the phosphorus release and uptake was well developed even though phosphorus release was not comparatively high. From this study, it was concluded that organic substrates, such as glucose seemed to be converted fatty acids after fast bio-sorption, followed by concurrent uptake of these acids by excess phosphorus removing bacteria.