• Bulletin of the Korean Chemical Society
• /
• 제17권4호
• /
• pp.373-376
• /
• 1996

The bulk thermal and photopolymerization of methyl methacrylate(MMA) with phenylsilane were performed to produce poly(MMA)s containing phenylsilyl moiety presumably as an end group. It was found for both thermal and photopolymerization that while the polymerization yields and polymer molecular weights decreased as the relative phenylsilane concentration increases, the TGA residue yields and the relative intensities of SiH IR stretching bands increased with increasing molar ratio of phenylsilane over MMA. The polymerization yield, molecular weight, and TGA residue yield for the thermal polymerization were higher than those for the photopolymerization. Thus, the phenylsilane seemed to significantly influence on the polymerization as both chain initiation and chain transfer agents. However, an appreciable silane effect was not observed on the thermal and photopolymerization of 4-vinylpyridine, acrylonitrile, styrene, and vinyltrimethoxysilane.

• 분석과학
• /
• 제15권3호
• /
• pp.287-299
• /
• 2002

인천연안지역 표층퇴적물의 PCBs 잔류농도는 우리 나라의 다른 연안지역 보다 비교적 낮은 농도로 검출되었고, 전지역에 걸쳐 Aroclors 혼합표준액 (1016+1232+1248+1260)과 유사한 패턴으로 배출되었으며, 염소조성비율 변화에 따라 A(Kanghwa), B(Yellow) 및 C(Jangdo) 등 3개의 지역군으로 분류되었다. 또한, 외해에 근접한 B 지역은 2, 3 염화물이, 매립지 침출수 처리수가 방류되는 C지역은 7, 8염화물이 다른 지역에 비해 높은 염소 조성비율을 나타내는 것으로 조사되었다. 연구대상지역 주상퇴적물의 PCBs 잔류농도는 강화수로에서 1.60~3.00 ng/g, 장도수문에서 0.34~9.20 ng/g으로 나타났으며, 두 지역 모두 하부층에서 상부층으로 올라갈수록 농도가 증가하는 경향을 나타내었다.

• 신재생에너지
• /
• 제5권2호
• /
• pp.9-14
• /
• 2009

Automobile Shredder Residue (ASR) is very appropriate in a gasification melting system. Gasification melting system, because of high reaction temperature over than $1,350^{\circ}C$, can reduce harmful materials. To use the gasification processes for hydrogen production, the high concentration of CO in syngas must be converted into hydrogen gas by using water gas shift reaction. In this study, the characteristics of shift reaction of the high temperature catalyst (KATALCO 71-5M) and the low temperature catalyst (KATALCO 83-3X) in the fixed - bed reactor has been determined by using simulation gas which is equal with the syngas composition of gasification melting process. The carbon monoxide composition has been decreased as the WGS reaction temperature has increased. And the occurrence quantity of the hydrogen and the carbon dioxide increased. When using the high temperature catalyst, the carbon monoxide conversion ratio ($1-CO_{out}/CO_{in}$) rose up to 95.8 from 55.6. Compared with average conversion ratio from the identical synthesis gas composition, the low temperature catalyst was better than the high temperature catalyst.

• 한국식품과학회지
• /
• 제41권6호
• /
• pp.722-726
• /
• 2009

Chlorothalonil, kresoxim-methyl 및 procymidone 농약성분은 고추 과육 대 꼭지에서의 잔류농도의 비율이 농약성분에 따라 1:2-5로서 고춧가루에 꼭지가 혼입될 경우 고춧가루 중 농약 잔류량이 약 20%만큼 상승할 수 있는 것으로 나타났다. 그러므로 고춧가루의 안전성 확보를 위해서는 고춧가루 제조 시 꼭지가 혼입되지 않도록 해야 할 것이다. 고추 과육 대 고춧잎에서는 실험 농약성분 3종의 잔류농도 비율이 농약성분에 따라 1:11-39로 나타났다. 이것은 현재 실험 농약 3종의 고춧잎에 대한 잔류허용기준의 비설정 조치가 기준 설정 여부의 판단기준에 부합되는 것임을 말한다. 그러나 chlorothalonil 수화제의 경우 고춧잎 식용금지 문구가 부재한데 이것은 식용금지 문구 포함 여부의 판단기준에 부합되지 않으므로 이에 대한 재검토가 필요하다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제13권11호
• /
• pp.1604-1608
• /
• 2000

Penicillin antibiotics such as penicillin G, ampicillin and amoxicillin have been widely used in the pig industry to control salmonellosis, bacterial pneumonia, and urinary tract infections. Extensive use of antibiotics in veterinary clinics has resulted in tissue residues and bacterial resistance. To prevent unwanted drug residues entering the human food chain, extensive control measures have been established by both government authorities and industries. The demands for reliable, simple, sensitive, rapid and low-cost methods for residue analysis of foods are increasing. In this study, we established a rapid prediction test for the detection of pigs with unacceptable tissue residues of penicillins. The recommended therapeutic doses of three penicillins, penillin G (withdrawal time, 7 days), ampicillin (withdrawal time, 7 days) and amoxicillin (withdrawal time, 14 days), were administered to three groups of 20 pigs each. Blood was sampled before drug administration and during the withdrawal period. The concentration of penicillins in plasma, determined by a semi-quantitative ELISA, were compared to that of internal standard, 4 ppb, which corresponded to the Maximum Residue Limit in milk. The absorbance ratio of internal standard to sample (B/Bs) was employed as an index to determine whether drug residues in pig tissues were negative or positive. That is, a B/Bs ratio less than 1 was considered residue positive, and larger than 1 negative. All 60 plasma samples from pigs were negative to three penicillins at pretreatment. Penicillin G could be detected in the plasma of the treated pigs until day 4 post-treatment and ampicillin until day 2, whereas amoxicillin could be detected until day 10 of its withdrawal period. The present study showed that the semi-quantitative ELISA could be easily adapted to detect residues of penicillin antibiotics (penicillin G, ampicillin and amoxicillin) in live pigs.

• Asian-Australasian Journal of Animal Sciences
• /
• 제13권12호
• /
• pp.1775-1778
• /
• 2000

Oxytetracycline has been widely used in the cattle industry to control pneumonia, shipping fever, foot rot, bacterial enteritis, and uterine infections. Extensive use of antibiotics in veterinary clinics has resulted in residues in tissue and bacterial resistance to antibiotics. To prevent unwanted drug residues from entering the human food chain, extensive control measures have been established by both government authorities and industries. The demands for reliable, simple, sensitive, rapid and low-cost methods for residue analysis of foods are increasing. In this study, we established a rapid test for tissue residues of oxytetracycline in cattle. The recommended therapeutic dose of oxytetracycline (withdrawal time, 14 days) was administered to 10 cattle. Blood samples were collected from each cow before drug administration and during the withdrawal period. The concentration of oxytetracycline in plasma, determined by a semi-quantitative ELISA, was compared to that of the internal standard, 10 ppb. The absorbance ratio of internal standard to sample (B/Bs) was employed as an index to determine whether the residues in cattle tissues were negative or positive. That is, a B/Bs ratio less than 1 was considered as residue positive and that greater than 1 as negative. Based on this criterion, all plasma samples from cattle were negative to oxytetracycline at pre-treatment. Oxytetracycline could be detected in the plasma treated cattle until day 14 post-treatment. The present study showed that the semi-quantitative ELISA could be easily adapted in predicting tissue residues for oxytetracycline in live cattle.

• Bulletin of the Korean Chemical Society
• /
• 제16권11호
• /
• pp.1056-1059
• /
• 1995

The bulk photopolymerization of methyl methacrylate (MMA) with primary arylsilane (e.g., phenylsilane) and various primary alkylsilanes (e.g., benzylsilane, 3-phenoxyphenyl-1-silabutane, 3-naphthyl-1-silabutane, and 3-chlorophenyl-1-silabutane) was performed to produce poly(MMA)s containing the corresponding silyl moiety as an end group. It was found for the phenylsilane that while the polymerization yields increased and then decreased with a turning point at the molar ratio of MMA:silane=10:1 as the relative silane concentration increases, the polymer molecular weights decreased, and the TGA residue yields and the relative intensities of SiH IR stretching bands increased with increment of molar ratio of silane over MMA. The photopolymerization yield of MMA with the arylsilane was found to be higher than those with the alkylsilanes and without the silanes. Thus, the silanes seemed to significantly influence on the photopolymerization as both chain initiation and chain transfer agents.

• 대한수의학회지
• /
• 제46권3호
• /
• pp.291-294
• /
• 2006

$Parallux^{TM}$, a solid-phase fluorescence immunoassay(SPFIA) developed for antibiotics residue detection in milk, was applied for analysis of fish muscle. The recommended therapeutic dose of ampicillin(100 mg/kg body weight, withdrawal period 7 days) was orally administered to a group of 25 olive flounders(Paralichthys olivaceus) for consecutive five days. Muscle was sampled after drug treatment 1st, 2nd, 3rd, 4th and 5th day. The concentration of ampicillin in muscle, determined by SPFIA, was compared with that of internal standard(10 ppb as ampicillin). The absorbance ratio of sample to internal standard(Bs/Bo) was employed as an index to determine the muscle residue in olive flounder. To investigate the recovery rate, the standard solutions were added to muscle samples to give final concentrations in muscle of 10 and 50 ng/ml. The recovery rates of all spiked samples were > 89% of the spiked value. Ampicillin was detected in muscle of fishes treated until the 3rd day of withdrawal period. The present study showed that the SPFIA can be easily adopted in predicting tissue residues for ampicillin in farmed fishes.

• KSBB Journal
• /
• 제10권5호
• /
• pp.598-603
• /
• 1995

현재 국내 주정공장에서 사용되고 있는 타파오카를 액화 및 당화시켜 얻은 당화액과 당화액에서 분 리된 고형분으로 회분실험과 total cell retention c culture 실험을 하였다. 당화액에 의한 회분 실험결과 에탄올 수율은 0.48 g-ethanol/g- (reducing s sugar)으로서 약 $180g/\ell$의 환원당이 36시간만에 거의 다 소모되어 약 $84g/\ell$의 에탄올이 생성되었다. 이 때 최종 효모농도는 $8.5{\times}107$ cellsjml(약$2.30g/\ell$) 이었다. 원료 중 환원당농도가 $224g/\ell$이고 희석속도가 $0.18h^{-1}$ 인 total cell retention culture 실험에서는 효모농도가 약 $40g/\ell$, 잔류 환원당농도 가 약 $15g/\ell$로서 포도당은 거의 소모된 것으로 나 타났다. 에탄올농도는 약 $81.4g/\ell$로서 이의 부피 생산성이 약 $14.7g/\ell$-h이었다. 원료 중 환원당농도가 $205g/\ell$ 이고 희석속도가 $0.2h^{-1}$이며 bleed가 있 는 cell retention culture 실험에서는 효모의 농도가 약 $22g/\ell$까지 증가하였고 에탄올농도는 $685g/\ell$부근에서 진통하였으며 생산성은 약 $13.6g/\ell$-h이 다. 약 $12g/\ell$의 잔류 환원당 중에 약 $4.5g/\ell$의 포도당이 포함되어 있었다. 타피오카 당화액으로부터 분리된 고형분을 사용한 실험을 통하여 고형분도 기 질로서 효용가치가 어느 정도 있는 것으로 판명되었으며 당화액 발효조와 별도로 고형분 발효조의 개발도 필요한 것으로 생각되었다.

• 한국토양환경학회지
• /
• 제1권2호
• /
• pp.3-13
• /
• 1996

생물학적 복구법의 효율은 미생물 균수의 계수, 호흡율, 분해율 등으로 측정할 수 있으며 부작용 시험은 Daphnia,굴의 유충, 무지개 송어 를 사용하여 측정된다. On-Site처리에 있어서는 산소 전달이 문제가 되는데 이에는 과산화 수소가 사용될수 있으며(벤젠계통의 용매), 유류오염 방제시에는 친유화적 질소 및 인을 첨가할 수 있다. 접종균주는 혼합균주 또는 순수 균주가 사용되는데 후자에는 Pseudomonas와 Phaneochate 등이 있다. 때로는 효울을 높이기 위해 효소를 첨가 하거나 광분해법과 병용되기도 한다. 토양의 유류오염물질, 예컨대 폐윤활유, 기계유, 오일 슬러지들을 처리할때는 토양상부 15∼20cm를 갈고 유류오염물질을 5%의 농도로 주입한다. 이 때 적정 pH는 7∼8, 탄화수소 질소 = 100 : 1, 탄화수소 : 인 = 800 : 1이며 적절한 배수가 필요하다. 지하 유류오염물질의 처리에 있어서는 특히 다량의 산소가 필요하며 해양유류오염물질의 처리에 있어서는 친유화성 비료를 첨가하면 효과가 있다 생물학적 복구법에 의해 대기오염물질 특히, 악취 물질을 처리할 수 있는데 반응기로는 생물여과법과 생물세정기가 쓰인다.