• 미생물학회지
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• 제20권4호
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• pp.183-188
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• 1982

Clostidium botulinum type B가 생성하는 독소를 정제할 수 있는 방법을 연구하였다. 정제과정은 독소를 ammonium sulfate로 배양액에서 침전시켜 추출한후 Polymin P를 처리하여 핵산 및 기타 단백질을 최대한 제거한 후 Sephaex G-I00에서 gel fiItration을 시키고 DEAE-Sephadex로 이온교환 크로마토그래피를 시켰다. 이러한 과정으로 정제된 독소의 회수율은 17%였으며 SDS-polyacrylamide gel electrophoresis 결과 하나의 선을 나타내 동질성을 증명하였다. 정제된 독소의 분자량은 163,000이였으며 $\beta$-mercaptoethanol을 사용하여 환원시킨 결과 분자량 106,000과 56,000의 하위 단위체로 분리되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.232-235
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• 2004

This study aims to manufacture non-sintering cement(NSC) by adding phosphogypsum(PG) and waste lime(WL) to granulated blast furnace slag(GBFS) as sulfate and alkali activators. This study also investigates the basic physical properties and hydration reaction of NSC, and evaluates its reusing possibility as construction material. Results obtained from this study have shown that GBFS was affected by $So_4^{2-}$ in waste PG and stimuli under wet condition, left slag components, created Ettringite and CSH gels, and eventually started being hydrated. These hydrated creations formed dense structures like CSH based on Ettringite and contributed in allowing the mortar to reveal high strength.

• International Journal of Concrete Structures and Materials
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• 제8권1호
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• pp.61-68
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• 2014

This paper reports the physical properties and hydration products of slag cement that was prepared by activating ground granulated blast furnace slag with commercial lime and plaster of Paris (POP) as activators. The consistency, setting times and soundness of various mixes of slag-lime-POP is reported. The hydration products and formation of bonds in the paste during setting were studied with the help of SEM, FTIR and XRD tests and the same are correlated to the hydration process. The setting times of the mixes are found to be lower than that of the value prescribed for ordinary Portland cement (OPC). Borax is used as a setting retarder and a borax content of 0.4 % by mass gives setting times that are normally prescribed for OPC. In the early stages of setting C-A-S-H gels are found in this cementing material instead of C-S-H gel, as generally observed in the OPC.

• Current Research on Agriculture and Life Sciences
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• 제32권1호
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• pp.34-42
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• 2014

Soy and fermented soy are popular and recognized as a health food among Koreans. Since soy proteins are known to be protease resistant, even to pepsin and pancreatin, it is hypothesized that soy proteins may interact with the intestinal tract and trigger certain physiological reactions. To test this hypothesis, mice were fed diets supplemented with soy, Chunkukjang, or casein. The differentially expressed proteins were analyzed using 2-D gels and identified by peptide mass fingerprinting using mass spectrometry. The majority of the differentially expressed proteins could be functionally grouped into metabolic enzymes and calcium-binding proteins. The differential protein expression by the soy-fed groups was also verified based on a representative protein, tropomyosin, using a Western blotting analysis. In addition, the soy-fed groups exhibited a taller villi structure. Therefore, this study suggests that soy proteins can be an effective nutrient and physiological stimulant for the intestines.

• 한국가금학회지
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• 제26권2호
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• pp.85-95
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• 1999

The mechanically deboned chicken meat(MDCM) has several limits in using for in using for in processed meat products as a main material because of poor color and textural properties, chance of microbial contamination and lipid oxidation. There has been a growing interest all over world in the application of MDCM to the surimi process. The surimi made from MDCM contains a high concentration of myofibrillar protein since this processing involves repeated washing processes with an aqueous solution in order to remove heme pigments, fat and other undesirable substances. The quality of the surimi made from MDCM is affected by various processing factors, such as kinds of wash solution, ion strength, washing cycle, temperature, pH changes, composition, part of muscle, particle size, and rigor state etc. A number of researchers havee investigated the effect of the various washing conditions on the properties of surimi gels. A fuller information of all the factors affecting surimi processing and gel formation by heat-induced gelation has not been known yet.

• Korea-Australia Rheology Journal
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• 제14권1호
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• pp.17-23
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• 2002

A novel and simple method using a cylindrical penetrometer is being developed for the measurement of yield stress. The principle of this technique is based on the measurement of the static equilibrium of a falling penetrometer in a yield stress fluid. The yield stress is simply determined by a balance of forces acting on the penetrometer. The yield stress of Carbopol gels and $TiO_2$ suspensions has been measured using this method. The results are in reasonable agreement with the values from conventional methods. The effects of the dimensions and weight of the penetrometer have been examined. The long-term behaviour was also observed. No measurable creep was seen and equilibrium was found to be very quickly established. The cylindrical penetrometer technique promises to be a simple, quick and reliable static method for the measurement of yield stress.

• BMB Reports
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• 제28권5호
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• pp.443-450
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• 1995

Cloned staphylococcal peptidoglycan hydrolase was used in determining the physiological characteristics of peptidoglycan hydrolase. This enzyme hydrolyzed the bacterial cell walls and released the N-terminal alanine, but not the reducing groups. This cloned gene product was localized in the cytoplasm of transformed Escherichia coli. Activity gels indicated the enzyme had an Mr of about 54,000, which was consistent with the deduced Mr from sequencing of the cloned gene. The activity bound to CM-cellulose but not DEAE-cellulose resin, indicating it as a basic protein. Enhanced enzyme activity in a low concentration of cations, and inhibited enzyme activity in a solution with dissolved phospholipids, suggested that the activity and the availability of this basic protein may be regulated between negatively charged and positively charged cellular molecules. The activity against boiled crude cell wall was much greater than against purifed cell wall, suggesting protein associated with crude cell wall may aid in the binding of the peptidoglycan hydrolase The cloned peptidoglycan hydrolase showed positive activity on whole cells of some lysostaphin-resistant coagulase-negative staphylococci. The cloned enzyme may be an alternative for lysostaphin for lysis of staphylococci.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.523.2-523
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• 1986

The hydrolysis of olive oil was attempted with immobilized C. rugosa lipase in the reverse phase solvent system. (i.e. immobilized wet particles is dispersed in continuous phase olive oil or organic solvents containing olive oil). Sephadex LH-20 and LH-60 were used as the supports that can be used in organic solvents. The water content of wet particles of sephadex LH-20 and LH-60 were about 72% (w/w) and 85% (w/w), respectively Both swollen gels with 0.05M buffers adsorbed about 18% of lipase dissolved. They were easily dispersed in liquid olive oil or in organic solvents. The effects of organic solvents on the stability and catalytic activity of the lipase have been examined. The results revealed that isooctane is superior to the other solvents examined for enzymatic fat spliting in reverse phase system. Kinetics of enzymatic hydrolys of olive oil by immobilized lipase has been investigated in a batch reactor. Effects of pH and temperature on the lipase were studied. The substrate concentration was influenced positively on the thermal stability.

• 한국분말재료학회지
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• 제18권1호
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• pp.35-40
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• 2011

LAS-system ceramic powder, spodumene ($Li_2O{\cdot}Al_2O_3{\cdot}4SiO_2$), was successfully synthesized by a chemical solution technique employing PVA(polyvinyl alcohol) as an organic carrier. The PVA content affected the microstructure of porous precursor gels and the crystalline development. The optimum PVA content contributed to homogeneous distribution of metal ions in the precursor gel and it resulted in the synthesis of glass free $\beta$-spodumene powder having a specific surface area of $7.57\;m^2/g$. The agglomerated $\beta$-spodumene powders were also enough soft to grind to fine powders by a simple ball milling process. The microstructures of the densified powder compacts were strongly dependant on the minor phases of spodumene solid solution and amount of liquid phase, which were formed from the inhomogeneous precursors.

• 한국수정란이식학회지
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• 제12권2호
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• pp.219-226
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• 1997

Follicular fluid influxed into the oviduct during ovulation may affect movement of sperm for fertilization Thus, in this study, the effect of follicular fluid, obtained from follicles of l0mm in diameter, on number and quality of sperm recovered by swim-up separation was investigated and sperm-movement stimulating components extracted from follicular fluid with methanol and isooctane were separated by gel filtration with Sepadex G-1O, G-25 and G-1OO gels, and were isolated by electrophoresis with SDS-PAGE mini gel. The results obtained were as follows; 1. Diluted follicular fluid stimulated sperm movement. 2. Sperm-movement stimulating factors were in methanol extract. 3. Sperm-movement stimulating effect of methanol extract appeared in fraction I among fractions recovered after gel filtration. And the fraction I contained proteins indicating 4 major bands as about 47, 43, 25 and 14 kilodaldons and 5 minor bands as about 67, 58, 23, 22 and 21 kilodaldons. 4. The fraction I recovered from G-100 gel showed significantly low percentage of motile sperm and had no protein indicating the band of 67 kilodaldons among the minor bands.