냉축열 잠열재로 Na2SO4.10H2O를 선정하여 냉축열을 위한 잠열축열 온도 수준을 NH4Cl과 KCI을 잠열온도 조절제로 활용하여 16℃에서 -0.3℃까지 조절하였으며, 상변화 사이클에 의한 열특성 변화 추이와 물성의 안정성을 실험 분석하여 다음과 같은 결과를 얻을 수 있었다. 1. 냉축열재로 선택한 Na2SO4.10H2O는 물성이 불안정한 상변화 잠열 재였으나, 조핵제로 BRX를, 증점제로 CBP를 첨가하여 물성을 안정시켰으며, NH4Cl과 KCl을 상변화 온도조절제로 선택하여 상변화 온도를 조절할 수 있다. 2. SSD＋NH4Cl서 NH4Cl을 g~21wt%로 증가시킴에 따라 상변화 온도는 16~-0.3℃로 조절할 수 있었으며, 잠열축열량은 30kca1/kg에서 23.4kca1/kg으로 감소하였고, 상변화 온도조절제, KCl을 l7wt%에서 25wt%로 증가시킴에 따라 상변화 온도를 14℃에서 4℃까지 조절할 수 있었다.

A simple, rapid and simultaneous analytical method is described for the detection of Sulfonamide and Tetracycline residues, i.e., Sulfamerazine (SMR), Sulfamethazine (SMT), Sulfamonomethoxine (SMM), Sulfadimethoxine (SDM), Sulfaquinoxaline (SQN), Oxytetracycline (OXY), Tetracycline (TC), Chlortetracycline (CTC). Blank control and sulfonamide and tetracycline fortified fish muscle samples (0.5 g) were blended with octadecylsilyl (C,e, 40 gm, 21% load, 60Å) derivatized silica packing material (2 g). Blended fish samples were washed with hexane, then, benzene and dichloromethane were used for the elution of tetracycline and sulfonamide, respectively, The eluants containg tetracycline and sulfonamide were analyzed by HPLC. Correlation coefficients of standard curves for individual sulfonamide and tetracycline isolated from fortified samples were linear (0.9993±0.0003-0.9997±0.0003, 0.9493±0.078-0.9753±0.036), respectively, The average percentage recoveries of sulfonamide and tetracycline ranged as 80.86-96.52% to 85.88-92.23%, and 30.01-37.12% to 65.89-73.40%, for the concentration range (0.1--1.0 ppm) examined, respectively. Limit of detection for sulfonamide was 0. 05 ug/g, then, tetracycline was 0.1 ug/g. Detection of quantitation of sulfonamide residue was 0.0012 ppm for SMR in Paralichthys Odiuacleus and 0.0020 ppm for SMR, 0.015 ppm for SMM in Cyprinus Carpio. The applicability of this procedure is demonstrated by separation and detection of incurred tetracycline and sulfonamide residues in fish muscle tissue.

본 연구에서는 LPCVD, PECVD, ECR plasma CVD방법을 이용하여 x선 노광 공정용 마스크의 투과막재료로써의 실리콘질화막의 증착과 그의 물성에 관하여 실험하였다. X선 노광 마스크용 투과막의 재질로써 요구되는 적정인장응력에 가지는 증착조건으로 실리콘질화막을 1μm정도의 두께로 증착하였으며 이 조건에서의 물성을 SIMS, XPS, ESR, AFM, spectrophoto-metry를 이용하여 비교 분석하였다. ECR plasma CVD방법으로 얻은 실리콘 질화막은 화학양론적 조성(Si/N=0.75)에 근접하는 막을 얻을 수 있었으며 표면 평활도와 가시광투과도가 가장 우수한 결과를 얻었다. 저온 증착법인 PECVD로 얻은 막은 Si/N비가 약 0.86정도이고 산소와 수소의 불순물함량이 가장 높게 나타났다. SiH2CI2를 이용한 LPCVD막의 경우는 Si-rich조성을 가지지만 수소 불순물의 함량이 가장 작게 나타났고 표면거칠기는 가장 나쁘게 나타났다. 그러나 위의 방법으로 얻은 실리콘 질화막의 최대 가시광투과도는 633nm파장에서 모두 90%이상의 값을 나타내었고, 또한 표면 평활도도 0.64-2.6nm(rms)로 현재 연구되고 있는 다른 X선 투과막재료보다 월등히 우수한 결과를 보였다.

The purposes of this study were to investigate the Maillard reactions of some oligosaccharides with lysine and the antioxidative effects of the ethanol extracts from their reaction mixtures on the soybean oil. The Maillard reactions were carried out of 2% oligosaccharides such as palatinose (PN), fructooligosaccharide (FO), isomaltooligosaccharide (IMO) with 2% lysine (L) for 24 hours heating at 60, 80, 100℃. The color intensity of Maillard reaction mixtures were determined by UV-VIS spectrophotometer upon reaction time and temperature. And the antioxidative effects on the soybean oil of each ethanol extract from Maillard reaction mixture of each oligosaccharide were measured by peroxide value (POV). POV's of soybean oil including reaction extracts were determined regularly every 2 days during 20 days storaged at 60±1℃. The results were obtained as follows: 1. The color intensity of the Maillard reaction mixtures were raised highly as the browning temperature and time increased. The color intensity of PN L browning mixture was the highest. The order of high color intensity at 100℃ was PN L〉FO L〉Glu L〉IMO L. 2. Comparing the antioxidative effect of Maillard reaction product (at 100℃, for 12 hours) of each oligosaccharide to that of BHT and TBHQ, the order of high antioxidative effect was TBHQ〉IMO L〉BHT〉Glu L〉PN L〉FO L. 3. From these results, it was known that PN L shown as high brown color intensity was appeared low antioxidative effect, while IMO L shown as low brown color intensity was appeared high antioxidative effect. So, it was recognized that there was no relation between brown color intensity and antioxidative effect.

BaTiO3물질은 뛰어난 유전체로 널리 알려져 왔으며 특히 Heywang등이 제안한 PTCR특성은 이 물질의 응용범위를 세라믹 필터, 회로보호소자, 온도감지소자 및 저항가열장치 등으로 확대시켰다. 이러한 특성의 발현기구는 아직까지 밝혀지지 않은 상태이지만 제 특성을 향상시키기 위한 노력은 계속되어왔다. 특히 개발목적에 맞게 온도에 따른 정저항 특성(PTCR; Positive temperature constnat of resistivity phenomena)을 설계하려는 시도가 계속되어 왔으며 그 중에서도 페로브스카아트계의 2가와 4가의 양이온 자리를 등가나 원자가가 다른 양이온으로 치환하여 특성을 개선하려는 시도가 계속되어 왔다. 특히 Ca2+나 Sr2+는 Ba2+자리를 치환할 수 있는 물질로 개별적인 첨가에 대한 연구는 많은 연구자들에 의해 진행된 상태이지만 최종적인 영향이나 해석에 대해서는 연구자들간에 이견이 많은 상태이다. 이번 실험에서는 BaTiO3계에 합성한 (Ca, Sr)TiO3를 Ca와 Sr의 상대적인 비를 변화시키면서 전체적인 첨가량을 변화시켜 그에 따른 전기적 특성 및 미세구조를 살펴보았다. (Ca, Sr)TiO3의 첨가로 상온저항 및 PTCR특성을 변화시킬 수 있었으며 이를 통해 PTCR물질의 활용범위를 넓힐 수 있는 발판을 마련할 계기가 되었다. 특히 기존의 연구가 주로 개별적인 Ca나 Sr의 첨가에 의한 미세구조와 전기적 특성변화의 연구에 치중해 있었던 것과는 달리 Sr과 Ca을 함께 치환하여 상대적인 비가 특성에 더 중요한 영향을 끼치는 것을 확인하였으며 적절한 합성비를 선택하면 퀴리온도에서의 저항변화폭을 유지하면서 상온저항을 낮출 수 있음을 확인하였다.

This study was carried out in order to analyzed the changes in nitrogen containing taste compounds of three different types of traditional Korean soy sauce with varing ripening period, and to investigates correlation between sensory characteristics and taste compounds contents via contents assay and sensory evaluation of soy sauce samples. Total nitrogen, ammonia type nitrogen and amino type nitrogen contents showed the highest value in Kyupjang. 17 kinds of free amino acid was detected in Chungjangs and 16 kinds of free amino acid was detected in Kyupjang. Nucleotides and their related compounds detected were hypoxanthin, xanthin, IMP, AMP, Inosine, ADP. Free amino acid and nucleotides and their related compounds contents were highest in Kyupjang. Nitrogen related compounds content of high concentration soy sauce ripened over 150 days increased similarly with Kyupjang. In the sensory evaluation of soy sauce taste, Chungjang samples acquired the highest score in the offensive taste test while Kyupjang marked highest score for sweet taste, nutty taste, taste preference. High concentration soy sauce ripend over 150 days yielded the result similar to that of Kyupjang. Sweet taste showed positive correlation with nitrogen compounds. The materials that showed positive correlation with nutty and traditional soy sauce taste and taste preference were nitrogen compound, IMP, AMP. Except for tryptophan, all free amino acid showed positive correlation with nutty and traditional soy sauce taste. Particulary, taste preference correlated to lysine, aspartic acid and glutamic acid.

Various antimicrobial drug screen tests have been used in order to ensure food safety. However, the conventional screen teats, the Swab Test on Premises(STOP, USA), the Calf Antibiotic and Sulfa Teat(CAST, USA) and the European Economic Community 4-plate Test(FPT, EU) are not sufficiently rapid or sensitive enough to detect low levels of sulfa drugs in meat. We developed a new screen test kit for the determination of the antimicrobial residues in meat called the Bacillus megaterium Disk AssayBmDA). A comparison of BmDA with the older screen tests showed BmDA was as good as the older ones with several advantages. The new test kit is faster-it can be read in 4-6 hours instead of 16-18 hours. Moreover, BmDA can discriminate sulfa drugs from other antimicrobial drugs because p-aminobenzoic acid countacts the inhibiting action of sulfa drugs. Minimum detectable levels of sulfa drugs were significantly improved at the level of 0.025-0.1 ppm compared with the level of 1.0 ppm in FPT. A comparison of BmDA with the older screen tests in HPLC confirmed meat samples exeeded the Korean tolerance value of 0.1 ppm showed BmDA was the most sensitive in the microbiological screen tests. As the microbiological screen tests have already known, a person familiar with simple laboratory techniques should have no difficulty in using it to detect antimicrobial residues in meat. This would be a simple, economic method of antimicrobial residues detection which might be succesfully used by many laboratories.

The European Economic Community four plate test(EEC 4-plate test, FPT, EU) has been used for monitoring antimicrobial drug residues in meat by Local Veterinary Service Center in Korea. This study was performed to evaluate sensitivity and group specificity of some antimicrobial drugs in FPT and to compare FPT with Charm II test. The minimal detectable levels of targeted antimicrobial drugs tested with standard solutions were 0.025-1.0 ppm for 7 beta-lactams, 0.5-1.0 ppm for 4 aminoglycosides, 0.05-0.5 ppm for 5 macrolides, 0.05-0.25 ppm for 3 tetracyclines and 0.25-1.0 ppm for 6 sulfonamides. In identification of the families, five families of antimicrobial drugs were identified. In this case, beta-lactams, aminoglycosides, macrolides, tetracyclines and sulfonamides could be detectable. In comparison of FPT and Charm II test, the results of FPT were not accord with those of Charm II test having the group specificity of seven families of antimicrobial drugs in meat samples except some families like tetracyclines.

들깨를 150℃에서부터 210℃까지 10∼30분간 볶아서 착유한 들기름에 존재하는 갈색물질의 갈색도와 전자제공력과, 또한 기호성 및 산화 안정성을 검토하였다. 들기름으로 추출한 갈색물질은 들깨의 볶는 온도와 시간이 증가에 따라 증가하였다. 들깨는 210℃에서 30분간 볶아 착유한 들기름으로부터 추출한 갈색물질은 150℃에서 10분간 볶은 것에 비해 13배 정도 증가하였다. 한편 볶음조건에 따라 착유한 들기름 중의 갈색물질 추출물의 DPPH에 대한 전자제공력은 볶음온도와 시간 증가에 따라 향상되었다. 210℃에서 30분 볶아 착유한 들기름 중의 갈색물질은 150℃에서 10분 볶은 것에 비해 전자제공력이 약 3배 증가하였다. 기호성이 가장 우수한 들기름에 산화 안정성이 가장 좋은 들기름을 5∼20% 혼합한 15% 혼합량 것 중 기호도와 산화 안정성이 가장 우수하였다. 210℃에서 30분 볶아 착유한 들기름 중의 갈색물질은 190℃에서 20분 볶아 착유한 들기름의 산화 안정성을 증가시켰다.

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℃.