다공성 충전층반응기에서 기-액흐름양상의 전이와 액체체류량

손민일,함병호,조지훈,김태옥,장영준 明知大學校 産業技術硏究所 1996 産業技術硏究所論文集 Vol.15 No.-

For both downward and ward cement gas-liquid flow in a porous packed bed reactor the transition of gas-liquid flow pattern and liquid holdup were investigated experimentally in an air-water-Zeolite particle system. Experimental results showed that gas velocity at trickle-to-pulse flow transition boundary in the downflow system was decreased with increasing liquid velocity and that gas velocity at bubble-to-pulse flow transition boundary in the upflow system was nearly constant for lower liquid velocity, however, it was increased with increasing liquid velocity for turbulent flow region. We also found that the dynamic liquid holdup in the upflow system was higher than that in the downflow system and it was increased with increasing liquid velocity and with decreasing gas velocity. Furthermore,the dynamic liquid holdup was sensitively affected by liquid velocity at trickle flow in the downflow system while it was sensitively affected by gas velocity at bubble flow in the upflow system and at pulse flow in the downflow and upflow systems. For the porous particle system fluid velocities at gas-liquid flow transition boundaries and dynamic liquid holdup had nearly same that for the nonporous particle(glass bead) system.

가열처리에 의한 단감의 이화학적 특성

손규목,김광호,성태수,김종현,신동주,정지영,배영일 한국식품영양학회 2002 韓國食品營養學會誌 Vol.15 No.2

단감의 기능성 소재 및 기호성이 우수한 부원료로서의 이용 가능성을 확인하기 위하여 단감새옥를 전처리별 즉, 열처리 온도 (25℃, 75℃ 및 95℃) 에서 NaCl (0, 1, 3%) 농도별로 침적 (1, 5분) 하여 동결건조한 시료구를 대상으로 탄닌, 비타민 C, 색도 및 조직감 등을 분석한 결과는 다음과 같다. 탄닌 성분은 열처리 온도, NaCl 농도 및 침적시간이 증가할수록 탄닌함량이 감소하는 경향을 나타내었으며, 특히, 대조구 (420 mg%) 에 비해 95℃에서 1% 및 3% NaCl 농도에 5분간 침적시 각각 228 및 198 mg%로 감소하였다. 비타민 C 함량은 대조구 (122.4 mg%)에 비해 95℃에서 3% NaCl 농도에 5분간 침적시 75.8 mg% 로 감소하였고, 색도는 열처리 온도, NaCl 농도 및 침적시간이 증가할수록 L(명도) 및 b(황색)값이 뚜렷하게 증가한 반면, a(적색도) 값은 감소하였고, ??E 값은 증가하여 처리조건이 가중될수록 색의 변화가 진행됨을 알 수 있었다. 단감껍질과 전처리한 시료 (95℃, 1% NaCl, 5 분)의 flavonol 함량은 껍질에 myricetin(2.0 ㎍/g), quercetin (34. 5 ㎍/g) 및 kaemferol (1.1 ㎍/g) 성분이 검출되었고, 전처리한 시료는 myricetin (9.5 ㎍/g), quercetin (5.5 ㎍/g)이 검출되었다. 조직감은 대조구에 비해 전처리 (95℃, 1% NaCl, 5분) 한 시료에서 부서짐성, 응집성, 점성 및 씹힘성이 우수하였다. 관능검사는 95℃에서 1% NaCl에 5분 및 3% NaCl 농도에 1부간 침지한 시료가 좋은 평가를 받았다. Sweet persimmon were tested in order to identify their use as secondary material which is excellent in function and taste as food. Samples were soaked for 1 and 5 min with NaCl concentration (0, 1 and 3%) at a certain heating temperature (25, 75 and 9r℃), and then tannin, vitamin C, flavonol, color intensity, sensory test and textural properties were analyzed. The results of the analyses were as follows. Tannins were decreased as heating temperature, NaCl concentration and soaking time were increased, especially, that the control was 420 mg% but decreased 228 and 198 mg% at 95℃ (1 and 3% NaCl concentration) for 5 min, soaked in each. Vitamin C content also decreased more in higher temperature and NaCl concentration than control (122.4 mg%). Color intensity showed higher value in L and b than in heating temperature, NaCl concentration and soaked time longer remarkably, but a value decreased. The peel of sweet persimmons was analyzed myricetin (2.0 ㎍/g), quercetin (34.5 ㎍/g) and kaemperaol (1.1 ㎍/g), but in pre-treatment sample ( 95℃, 1% NaCl concentration and 5 min, soaked ) was showed higher myricetin (9.5 ㎍/g) and quercetin (5.5 ㎍/g). Textural properties were good in pre-treatment sample ( 95℃, 1% NaCl concentration and 5 min, soaked) such as brittleness, cohesiveness, gumminess and chewiness. In sensory analysis, the pre-treatment samples (95℃, 1% NaCl concentration and 5 min, soaked and 95℃, 3% NaCl concentration and 1 min, soaked) were showed higher point than others.

外傷性 肝臟破裂과 肝膽道出血患者의 肝動脈結柴에 依한 治療

孫鍾夏,咸泰元,林敏一,裵振善,韓萬靑 대한적십자사 1974 적십자병원지 Vol.1 No.1

키틴/키토산을 이용한 의료용 재료의 개발

손태일,김선정 中央大學校 遺傳工學硏究所 1997 遺傳工學硏究論集 Vol.10 No.1

의료용 재료에 대한 키틴의 개발연구는 흡수성, 봉합사, 이공피부에 선행해서 검토되었으며, 현재로는 이미 실용단계에 있으며, 널리 임상실험이 행해지고 있다. 또한 위에서 기술한 이외의 품목에 있어서도 시험임상단계에 있는 것도 많으며, 실제로 의료품으로서 의료 시장에 등장할 날도 머지 않았다고 생각된다. 수년전까지는 키틴의 의용재료로서의 가능성은 단순한 아이디어 단계에 지나지 않았던 것을 생각해보면 커다란 진보라고 할 수 있다. 키틴은 화학구조가 셀룰로오스와 유사하며, 성형체의 외관, 물성도 비슷하지만, 생체 환경에 놓여 있는 경우 다른 재료와는 현저히 다른 성상을 나타낸다. 즉 열상과 같이 환경이 급격히 변화해 있는곳에 놓여 있어도, 또한 복강내와 같이 정상적인 생체표면에 있어서도, 생체와의 세포레벨반응은 완화하며, 오히려 적극적으로 생체수복을 도와주는 기능이 발견되었다. 또한 자신이 조금 분해되면서 생체와의 친화성을 유지한다고 하는, 생체반응에 대한 완충작용을 하고 있다고 말할 수 있다. 이 사실은 기계적강도가 높은 키틴성형체를 사용하는 것으로 생체내에서 안정되고 고정된 구조재료로서의 역할을 하면서 키틴특유의 기능을 발휘한다. 종래의 것에 발견되지 않았던 특징 있는 재료라고 할 수 있다. 키틴은 앞으로 화학적 방법에 의해서 더욱더 기능이 높은 많은 것을 제공하리라고 생각된다. 그것이 실현되면 이번에 기술한 것 뿐만아니라 생체재료로서의 꿈은 더욱 넓어지리라 기대된다. Chitin(poly-N-acetylglucosamine)/Chitosan(poly-N-aminoglucosamine) from crab shells is known to biocompatible materials, to have an accelerating effect on wound healing Several absorbable suture materials; polyglycolic acid(PGA), plain catgut and chromic catgut compared with chitin were tested. The tensile strength retention in artifitial gastric juice(pH 1.2), human bile(pH 6.7) and human pancreatic juice(pH 8.2); chitin was preserved up to 30 days but the other samples had dissolved within. Biodegradation and absorption of chitin are two pathways as being the in vivo metabolism; resolved by lysozyme, and reproduced to glycoprotein.

급속응고된 N-type Bi₂Te_(2.75)Se_(0.15) 열전재료의 미세조직과 열전특성에 미치는 압출비의 영향

김태경,이상일,임종호,손현택,김택수,천병선 대한금속재료학회 2005 대한금속·재료학회지 Vol.43 No.1

The n-Type thermoelectric compounds of Bi₂Te_(2.75)Se_(0.15) doped with 0.1 wt% SbI₃ were fabricated by gas atomization process and extruded under ratio of 16:1 and 28:1 at 450℃. The effect of extrusion ratio on the microstructures and thermoelectric properties were investigated by a combination of microscopy, XRD and thermoelectric properties. Grains of extruded bars are smaller than those of heated powder at extrusion temperature (450℃) due to the dynamic recrystallization but with increasing the amount of plastic deformation, grains of specimen extruded with 28:1 were slightly coarse. The compressive strength of hot extruded bar under 28:1 is 160 MPa and with decreasing the extrusion ratio to 16:1, the value is 250 MPa. The Seebeck coefficient a and electrical resistivity p were decreased with increasing ratio, while thermal conductivity x was increased. this results from decrease of carrier scattering and increase of carrier mobility. Extruded bar under ratio of 16:1 shows the higher value of figure of merit (Z=2.50x10^(-3)/K) than that of 28:1 (Z=2.07x10^(-3)/K). (Received June 24, 2004)

스포츠 집단의 커뮤니케이션 만족과 집단 응집력의 관계

문태영,손원일 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.3

This study is designed to shed light on the relationship between the communication satisfaction of sports groups on collective cohesion. With this in mind, the researcher looked into the communications and collective cohesion of sports group. The researcher conducted frequency, percentage, t-test and correlation, etc. The subjects were composed of a total of 392 out of 420(the population) belonging to 34 teams participating in a nationwide volleyball game for middle and high school boys and girls. The questionnaire was supposed to be self-administered. 28 copies were excluded from the population by thinking that their response were poor. The following are the findings. First, the subjects were highly satisfied with communications. The subjects with a high standard of living, middle school students, and subjects to participate in a lot of games turned out to be highly satisfied with communication. Second, the subjects had a high degree of social cohesion and assignment-based cohesion, and girls and players with less than two-to-three-year career had a higher degree of social cohesion. Third, the survey on the correlation between the communication satisfaction of sports groups and their collective cohesion shows that the more highly satisfied they are, the higher social cohesion and collective cohesion they had.

농산물 소독과정에서 브롬화메틸에 노출된 근로자에게 발생한 신경병 2례

박태혁,김정일,손지언,김종국,김형수,정갑열,김준연 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.4

목적 : 농산물 소독과정에서 브롬화메틸에 노출된 근로자에게 발생한 신경병 2례 보고. 방법 : 피로감, 전신무력감, 어지럼증, 보행장애 등의 증상을 주소로 내원한 브롬화메틸을 사용하여 방역작업에 종사하는 건강한 20세와 18세의 근로자를 대상으로 혈액검사, 신경정도 및 근전도검사, 뇌자기공명영상 등의 임상검사와 작업력조사를 시행하였다. 결과 : 1례에서 뇌자기공명영상에서 연수와 소뇌의 양측 측충부의 고신호강도가 관찰되었고 11일 후의 추적조사에서 동일 부위의 고신호강토가 감소된 소견이 관찰되었으며 뇌병증으로 최종 진단되었다. 다른 1례는 신경전도검사에서 다발성 신경병 소견과 뇌유발전위검사에서 우측 하부 뇌간부위 병소가 관찰되었고 뇌병증 및 말초신경 병으로 최종 진단되었다. 결론 : 근로자들의 증상은 소독과정에서 브롬화메틸 노출로 인한 신경 병으로 판단되며 훈증소독과방역작업에 종사하는 근로자들의 실태조사와 안전에 대한 대책이 시급하다고 하겠다. Objectives : To report two cases of neuropathy due to methyl bromide intoxication. Methods : Workers, engaged in the fumigating process, complained fatigue, general weakness, ataxia, and hypersomnia. We evaluated them with blood tests, neurophysiologic studies and MRI and investigated their occupational history. Results : Increased signal intensities were found in the medulla oblongata and paraver mian of cerebellum in MRI and after 11 days, high signal intensities were reduced in the following MRI. In the other case, polyneuropathy and rlght lower brainstem lesion were observed In the NCV and BAEP studies. Conclusions : We confirmed that worker's symptoms were related to methyl bromide exposure in the fumigation. It is necessary that we should evaluate present condition of fumigating process and prepare appropriate methods to protect workers engaged in the fumigation.

기-액병류상향 충전탑에서 액체체류량과 축방향혼합특성

조지훈,손민일,박용성,함병호,김태옥 明知大學校 産業技術硏究所 1993 産業技術硏究所論文集 Vol.12 No.-

For upward cocurrent gas-liquid flow in a packed column, holdup and axial mixing characteristics of liquid were investigated. In an air-water-glass bead system. liquid holdup and residence time distribution(RTD) were measured and Peclet number based on axial dispersion model was evaluated from experimental RTD. We found that liquid holdup was increased with increasing liquid velocity and size of packing material, and it was decreased with increasing gas velocity. Also, liquid holdup for the cocurrent up flow system was larger than that for the downflow system at the same experimental conditions. As increasing gas velocity, the in fluence of packing size and operation method on liquid holdup was reduced. The calculated Peclet number was not affected by gas velocity, and it was increased with increasing liquid velocity and with decreasing packing size. Furthermore, the effect of liquid velocity on Petlet number for higher liquid Reynolds number(Re1>70) was larger than that for lower Re1. In these conditions, correlations of the dynamic liquid holdup and the Bodenstein number were obtained.

방사선에 의해 제조된 pH 및 온도에 민감한 수화겔의 물성연구 및 약물방출에 관한 연구

김현우,노영창,손태일 한국공업화학회 2003 공업화학 Vol.14 No.3

N-isopropylacrylamide (NIPAAm)와 acrylic acid (AA)를 증류수에 일정한 몰비로 용해한 것과 여기에 butyl acrylate (BA)를 혼합한 용액을 상온에서 30, 50 kGy로 γ-선 조사하여 중합반응과 가교를 동시에 일으켜 pH 및 온도에 민감한 수화겔을 제조하였다. 제조된 수화겔은 pH 2, 7의 용액에서 5~40℃로 온도를 변화시켜 각각의 온도에서 최대 팽윤도를 측정하고 한편으로는 37℃로 고정한 후 PH 2~8까지 pH에 대한 최대 팽윤도를 측정하였다. 수화겔의 팽윤과 수축에 이온강도가 어떤 영향을 미치는지 알아보기 위해 0, 0.01, 0.03 N의 염화나트륨 용액에서 팽윤실험을 하였다. 경구용 인슐린 전달제재를 제조할 목적으로 수화겔이 최대 팽윤할 수 있는 최저의 온도와 pH 조건에서 인슐린을 탑재한 다음 자연건조(air dried)와 동결건조(freeze dried)를 하여 인슐린을 함유한 겔(drug-gels)을 제조하였으며, 인슐린 탑재 후 남은 인슐린 용액으로부터 탑재효율을 구하였다. Drug-gel은 in vitro에서 인공위액(simulated gastric fluid; SGF)과 인공장액(simulated intestinal fluid ; SIF)에서 약물 방출량을 측정하여 방출속도를 측정하였다. Temperature and pH sensitive N-isopropyacrylamide-acrylic acid (NIPAAm-AA) and N-isopropylacrylamide-acrylic acid-butyl acrylate (NIPAAm-AA-BA) hydrogels were synthesized by simultaneous polymerization and crosslinking of NIPAAm AA, and BA monomers in aqueous solution using γ-rays from ^60Co source at room temperature. The measurements of equilibrium water content on the synthesized hydrogels were made at the temperature ranging from 5 to 40℃ and pH 2 and 7. The prepared hydrogels had temperature-sensitive (30~35℃) and pH-sensitive swelling behavior. The HIPAAm-AA and NIPAAm-AA-BA hydrogels were used in drug delivery systems for the controlled release of insulin Insulin has been shown to have binding sites for hydrophobic molecules. Thus, it is likely that insulin binds specifically to the butyl side. The gels including insulin were prepared by air drying or freeze drying after loading insulin in solution (14.1 IU/mL) at 5℃ and pH 7. Drug-gels were plated in simulated gastric fluid (SGF; pH 1.2) at 37℃ for 2 h and then at simulated intestinal fluid (SIF : pH 7.3). The insulin release of the drug-gels was examined by UY analysis.

Euglena gracilis Z에 의한 CO_2 고정화

이재우,박봉선,손태일 中央大學校 食糧資源硏究所 2002 食糧資源硏究所 論文集 Vol.14 No.1

The Biological carbon dioxide fixation using microalgae has been known as an effective carbon dioxide reduction technology. With many environmental factors influencing microalgal productivity, the desirable CO^2 concentration and cultivation factors were investigated using a green algae, Euglena gracilis. It has the high protein and vitamin I to be used as fodder. In batch culture, initial pH, temperature and carbon dioxide concentration in the optimum cultivation condition were pH 3.5, 27℃ and 10%, respectively.