• 제목/요약/키워드: $CO_2$ solubility

검색결과 364건 처리시간 0.027초

개념 변화 수업에서 협동학습 환경이 학생들의 인지적, 정의적 결과에 미치는 효과 (The Effect of Cooperative Learning Environments in Conceptual Change Instruction on Students' Cognitive and Affective Outcomes)

  • 한재영;정은희;노태희
    • 한국과학교육학회지
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    • 제25권5호
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    • pp.555-562
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    • 2005
  • 이 연구에서는 개념 변화 수업에서 협동적 학습 환경의 효과를 개념 이해도, 성취도, 과학 학습 동기, 과학 수업에 대한 태도 및 수업 참여도에 대한 인식 측면에서 조사하였다. 1개 남녀 공학 중학교의 2학년 2개 학급을 비교 집단과 처치 집단으로 각각 배치하고, '물질의 특성' 단원의 밀도, 끓는점, 어는점, 용해도에 대하여 11차시 동안 수업을 실시하였다. 처치집단에서는 협동적 개념 변화 수업을 실시하였고, 비교 집단에서는 개별적 개념 변화 수업을 실시하였다. Mann-Whitney Test 결과, 처치 집단의 개념 검사 점수와 성취도 검사 점수가 비교 집단에 비해 유의미하게 높았으며, 처치 집단의 수업 참여도에 대한 인식이 비교 집단에 비해 더 긍정적인 것으로 나타났다. 이원 공변량 분석 결과, 처치 집단의 학습 동기 검사 점수가 비교 집단에 비해 유의미하게 높았으나, 과학 수업에 대한 태도에서는 두 집단 간에 유의미한 차이가 나타나지 않았다.

민태(Johnius belengeri) frame 단백질 가수분해물의 인산화에 의한 기능성 개선 (Improvement of the Functionalities by Phosphorylation of Hoki(Johnius belengeri) Frame Protein Hydrolysates)

  • 전유진;이병조;박표잠;변희국;김세권
    • Applied Biological Chemistry
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    • 제42권2호
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    • pp.128-133
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    • 1999
  • 참치내장 중 유문수 조직에 내재되어 있는 단백질 분해효소를 부분정제하여 추출한 후 민태 frame 단백질의 효소적 가수분해에 이용하였으며, 제조된 가수분해물을 한외여과막을 이용하여 분자량 크기에 따라 분획한 후 기능성을 개선시킬 목적으로 cyclic sodium trimetaphosphate를 이용하여 인산화 민태 frame 단백질 가수분해 물을 제조하고, 용해도, 유화성 및 포말성 등과 같은 기능성을 검토하였다. 1 가수분해물의 기능성 개선을 목적으로 가수분해물에 STMP를 처리하여 인산화된 가수분해물을 제조하였으며, IR 스펙트럼으로 인산화를 확인한 결과, $1300\;cm^{-1}$에서 P=O의 흡수띠를, $1000{\sim}1100\;^{-1}$에서 P-O-C와 alkyl group에 결합된 P-O-C의 흡수띠를 확인하였다. 2. 민태 frame 단백질 가수분해물을 인산화시킴으로써 용해도는 물론 유화성 및 유화 안정성 그리고 포말 안정성 등 기능성의 개선에 크게 효과를 나타내었다. 특히 분자량이 가장 큰 획분인 P-30K 가수분해물은 모든 기능성 부분에서 좋은 결과를 나타내어 미이용자원으로부터 기능성이 부여된 새로운 가치의 물질로서 활용이 기대된다.

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이산화탄소-이소프로필 알코올계: 고압 상거동 및 SAFT 상태방정식 적용 (Carbon Dioxide-Isopropyl Alcohol System: High Pressure Phase Behavior and Application with SAFT Equation of State)

  • 곽철;변헌수
    • 공업화학
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    • 제10권2호
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    • pp.324-329
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    • 1999
  • 본 연구에서는 고압하에서 이산화탄소와 이소프로필 알코올과의 이성분계에 대한 상평형데이터를 얻기 위해 실험을 수행하였다. 실험장치는 정지형 (static type)을 사용하였으며, 정확도를 실험하기 위해 $80^{\circ}C$에서 이산화탄소-이소프로필 알코올계의 실험을 수행하여 Radosz의 실험결과와 비교하였다. 이산화탄소-이소프로필 알코올과의 이성분계 상거동 실험은 온도 40, 60, 80, 100, 그리고 $120^{\circ}C$에서 실험하였으며, 이때 압력은 41~133 bar 범위였다. 이산화탄소-이소프로필 알코올계에 대해 동일한 압력에서 용해도는 온도가 증가함에 따라 증가함을 알 수 있다. 또한 순성분 이산화탄소와 이소프로필 알코올의 증기압을 서로 연결하는 혼합물 임계곡선을 나타내었다. 본 연구에서 실험한 결과를 statistical associating fluid theory (SAFT)상태방정식에 의해 계산하였으며, 그 결과 온도에 독립적인 두 파라미터에 의해 곡선을 결정하였다.

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Characterization of Acid- and Pepsin-soluble Collagens from Rockfish Sebastes schlegeli Skin

  • Kim, Hyung-Jun;Jee, Seong-Joon;Yoon, Min-Suck;Youn, Mu-Ho;Kang, Kyung-Tae;Lee, Dong-Ho;Heu, Min-Soo;Kim, Jin-Soo
    • Fisheries and Aquatic Sciences
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    • 제12권1호
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    • pp.6-15
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    • 2009
  • Biochemical and functional properties of acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) from rockfish skin were characterized. Yield of PSC (90.0%) was higher than that of ASC (63.2%). Both ASC and the PSC consisted of ${\alpha}1$ and ${\alpha}2$ chains, and $\alpha$-cross-linked components. According to the results of hydroxylation of proline and lysine, and FT-IR, no difference between the helical structure of ASC and PSC was identified. Thermal denaturation temperature (TDT) of ASC from rockfish skin was $22.8^{\circ}C$, the same as exhibited in PSC. Both ASC and PSC were higher in water absorption capacity (WAC) and oil absorption capacity (OAC) than other vegetable proteins. According to the results of emulsifying activity (EA) and cooking stability (CS), both ASC and PSC from rockfish skin were inferior compared to the commercial emulsifier (Tween-80). The results of FT-IR suggested that the structure of PSC was slightly different when compared to that of ASC. No differences in solubility were established between ASC and PSC from rockfish skin at various pH and NaCl concentrations.

한국산 인삼 단백질의 용해성 및 전기영동 패턴 (Solubility and Electrophoretic pattern of Korea Ginseng Protein)

  • 최청;윤상홍;배만종;안봉전
    • Applied Biological Chemistry
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    • 제28권2호
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    • pp.88-91
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    • 1985
  • 한국산 인삼 단백질의 생화학적 특성을 체계적으로 규명하기 위하여 단백질의 분별정량, SDS polyacrylamide gel 전기영동, pH에 의한 단백질의 용출성 및 아미노산 포성을 분석한 결과는 다음과 같다. 인삼 단백질의 분별정량은 albumin이 66.0%로 가장 많았으며 glutelin이 20.5%이었고 인삼 단백질의 pH에 의한 용출성은 pH3에서 최저를 나타내었으며 $pH6{\sim}8$에서 최고치를 나타내었고 염의 종류 및 그 농도별에 의한 추출성은 sodium염의 경우 차이가 없었다. 수용성 단백질의 침전도는 40%의 ammonium sulfate와 acetone에 의하여 96% 침전하였으며 SDS-poly-acrylamide gel 전기영동의 결과 11개의 band가 확인되었으며 수용성 단백질의 주 단백질의 분자량은 43,000이었다. 수용성 단백질의 아미노산조성은 18종류로써 arginine의 함량이 45.17%로 가장 많았으며 proline 및 cystine의 함량은 매우 낮았다.

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(구)장항제련소 주변 송림숲 등 식생지역에서의 비소오염토양 위해도 저감 조치: 안정화 공법 적용성 평가 및 사후관리 계획 (Risk Mitigation Measures in Arsenic-contaminated Soil at the Forest Area Near the Former Janghang Smelter Site: Applicability of Stabilization Technique and Follow-up Management Plan)

  • 안진성;양경;강우재;이정선;남경필
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제22권6호
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    • pp.1-11
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    • 2017
  • This study was conducted to investigate the performance of four commercial chemical agents in stabilizing arsenic (As) in soil at the forest area near the former Janghang smelter site. After amending the stabilizing agents (A, B, C, and D) into As-contaminated soil samples, synthetic precipitation leaching procedure (SPLP) and solubility bioavailability research consortium (SBRC)-extractable As concentrations significantly decreased except for agent D, which is mainly composed of fly ash and calcium carbonate. Increase of SPLP and SBRC-extractable As concentrations in four soil samples (S1, S2, S3, and J2) was attributed to desorption of As adsorbed on iron oxides due to high pH generated by agent D. It is therefore necessary to consider application conditions according to soil characteristics such as pH and buffering capacity. Results of sequential extraction showed that readily extractable fractions of As in soil (i.e., sum of $SO_4-$ and $PO_4-extractable$ As in soil) were converted into non-readily extractable fractions by amending agents A, B, and C. Such changes in the As distribution in soil resulted in the decrease of SPLP and SBRC-extractable As concentration. A series of follow-up monitoring and management plan has been suggested to assess the longevity of the stabilization treatments in the site.

Carbofuran과 Chiorothalonil의 공존이 Brachydanio rerio(zebrafish)를 이용한 단기간 생물농축계수의 측정에 미치는 영향 (Effect of Co-existence of Carbofuran and Chlorothalonil on the Short-term Bioconcentration Factor in Brachydanio rerio(zebrafish))

  • 민경진;차춘근
    • 한국환경보건학회지
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    • 제23권2호
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    • pp.64-71
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    • 1997
  • This study was performed to investigate the effect of co-existence of carbofuran and chlorothalonil on the short-term bioconcentration factor in Brachydanio rerio(zebrafish). The fishes were exposed to the single and combined treatment of carbofuran and chlorothalonil for 1, 3 and 5 days. Experimental concentrations of carbofuran were 0.05 and 0.10 ppm under the single treatment. And those of chlorothalonil were 0.005 and 0.010 ppm. Experimental concentrations of the combined treatment of carbofuran and chlorothalonil were 0.05 ppm+0.005 ppm, 0.05 ppm+0.010 ppm, 0.10 ppm+0.005 ppm for 1, 3 and 5 days, respectively. Carbofuran and chlorothalonil in fish and in test water were extracted with n-hexane and acetonitrile. GC-ECD was used to detect and quantitate carbofuran and chlorothalonil. 1-day, 3-day and 5-day bioconcentration factors(BCF$_1$, BCF$_3$ and BCF$_5$) of each pesticide were obtained from the quantitation results. The depuration rate of each pesticide was determined over the 24-h period after combined treatment. The results were as follows: Carbofuran did not bioaccumulate in zebrafish under the single and combined treatment for testing periods. BCF$_1$ values of chlorothalonil in concentration of 0.005 and 0.010 ppm under the single treatment were 0.508, 0.621, BCF$_3$ were 1.327, 1.511 and BCF$_5$ were 1.331, 1.597, respectively. BCF$_1$ values of chlorothalonil were 0.512, 0.520 and 0.619, respectively, when the concentration of carbofuran and chlorothalonil in combined treatment were 0.05+0.005, 0.05+0.010 and 0.10+0.005 ppm. BCF$_3$ values of chlorothalonil 1.341, 1.338 and 1.513, respectively, and BCF$_5$ values of chlorothalonil were 1.332, 1.327 and 1.521, respectively, under the above combined treatment. Depuration rate constants of chlorothalonil in concentration of 0.005 and 0.010 ppm under the single treatment were 0.011 and 0.012. Depuration rate constants of chlorothalonil were 0.011, 0.010 and 0.011, when the concentration of carbofuran and chlorothalonil in combined treatment were 0.05+0.005, 0.05+0.010 and 0.10+0.005 ppm. It was observed that no significant difference of carbofuran and chlorothalonil concentration in fish extracts, test water, BCFs and depuration rate constants of carbofuran and chlorothalonil between combined treatment and single treatment. It was considered that no appreciable interaction at experimental concentrations due to lower concentrations than LC$_{50}$. It is suggested that the difference of BCFs between carbofuran and chlorothalonil due to those of fat composition of fish and solubility of carbofuran and chlorothaionil.

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Immunostimulating Activity and Characterization of Polysaccharides from Mycelium of Phellinus linteus

  • Lee, Jae Hoon;Soo Muk Cho;Kyung Sik Song;Sang Bae Han;Hwan Mook Kim;Nam Doo Hong;Ick Dong Yoo
    • Journal of Microbiology and Biotechnology
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    • 제6권3호
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    • pp.213-218
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    • 1996
  • Hot-water extract, Fr. 1, of Phellinus linteus mycelium was fractionated into Fr. 2, 3, 4, and 5 by the difference of solubility in ethanol. The polysaccharide fractions were studied for their immunostimulating activity on in vitro T-independent polyc1onal antibody response to trinitrophenyl-haptened SRBC (sheep red blood cell). The Fr. 4 with the highest immunostimulating activity was subjected to DEAE-cellulose ion exchange chromatography and gave five fractions, 4-I, II, III, IV, and V. The in vitro immunostimulating assay of the five fractions showed that 4-I and 4-III had a similar activity to that of LPS but the other fractions had low activity. By analyses of chemical composition and HPLC, all fractions obtained were found to be heteropolysaccharide-protein complex. The molecular weights ranged from 9, 000 to 15, 000. Sugar analyses showed that glucose, galactose, mannose, arabinose, and xylose were main component. Uronic acid and amino sugar were also detected in the fractions. It should be noted that the molecular weight (15, 000) of 4-III was very small and the structure of 4-III may be different from the known immunostimulating branched $\beta$-(1longrightarrow3)-glucan.

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Soluble Expression of Recombinant Human Smp30 for Detecting Serum Smp30 Antibody Levels in Hepatocellular Carcinoma Patients

  • Zhang, Sheng-Chang;Huang, Peng;Zhao, Yong-Xiang;Liu, Shu-Yan;He, Shu-Jia;Xie, Xiao-Xun;Luo, Gou-Rong;Zhou, Su-Fang
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권4호
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    • pp.2383-2386
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    • 2013
  • Senescence marker protein 30 (SMP30), a hepatocellular carcinoma (HCC) associated antigen, was earlier shown by our research group to be highly expressed in HCC paracancerous tissues, but have low levels in HCC tissues. In order to detect anti-SMP30 antibody in serum of HCC patients, we established pET30a-SMP30 and pColdIII-SMP30 expression systems in Escherichia coli. However, the expression product was mainly in the form of inclusion bodies. In this research, we used several combinations of chaperones, four molecular chaperone plasmids with pET30a-SMP30 and five molecular chaperone plasmids with pColdIII-SMP30 to increase the amount of soluble protein. Results showed that co-expression of HIS-SMP30 with pTf16, combined with the addition of osmosis-regulator, and a two-step expression resulted in the highest enhancement of solubility. A total of 175 cases of HCC serum were studied by ELISA to detect anti-SMP30 antibody with recombinant SMP30 protein. Some 22 were positive and x2 two-sided tests all showed P>0.05, although it remained unclear whether there was a relationship between positive cases and clinical diagnostic data.

폴리올(polyol)과 4,4'-디페닐메탄디이소시아네이트(MDI)를 혼합한 2액형 폴리우레탄 수지의 물성에 관한 연구 (A Study on the Properties of Two-Component Type Polyurethane Resins Mixing Polyol and 4,4'-diphenyl Methane Diisocynate)

  • 이범철;최상구
    • Elastomers and Composites
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    • 제36권4호
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    • pp.268-277
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    • 2001
  • PPG, PEG, trimethylolpropane(TMP) 등의 폴리올에 MDI(4,4'-diphenyl methane diisocyanate)를 각각 혼합하고 경화시켜 여러가지 물성을 측정하였다. 경화시간은 PEG와 TMP의 함량이 늘어날수록 짧게 나타났고 분자량의 효과보다는 관능기의 수에 더 큰 영향을 받았다. NCO-OH 반응은 NCO-NCO반응보다 활성적이고 빠르게 일어났다. 경도는 가교밀도와 분자구조의 영향을 받았으며 NCO-NCO 반응으로 생긴 도막은 취약하였고 NCO-OH간의 반응으로 생긴 도막은 유연하였다. 부착력은 결정화도와 수축율이 클수록 낮은 값을 나타내었으며 TMP 함량이 증량될수록 높은 값을 나타내었다. 난연성은 난연제의 종류와 함량에 영향을 받았으며 난연효과는 IXOL B-251이 가장 우수하였고 TCCP는 수지와의 상용성이 좋지 않아 부분적으로 분리되었다.

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