Tricalciumaluminate의 초기 수화반응에 미치는 $K_2O$의 영향

한기성,최만,서일영,Han, Ki-Sung,Choi, Man,Seo, Il-Young 한국세라믹학회 1982 한국세라믹학회지 Vol.19 No.2

Two kinds of clinker liquid melts, one containing 2.0% of $K_2O$ and the other without $K_2O$, were prepared with the similar composition as those developed during the firing of portland cement clinker. One portion of melt was quenched and found to consist of glass together with traces of proto-$C_3A$, and the other portion was allowed to cool spontaneously to crystallize $C_3A$ and calciumferrite well. The product obtained by crystallization of the melt without $K_2O$showed cubic $C_3A$, while orthorhombic $C_3A$ was formed from the crystallized product containing $K_2O$. Studies on the hydration behavior of the samples made from the melts with 30% of gypsum were carried out for 24 hours by observation at regular intervals ettringite, monosulphate hydrates and gypsum which were formed or consumed during hydration. The samples without $K_2O$ in the melts were hydrated wth addition of proper amount of $K_2SO_4$ in the water for hydration. Hydration behavior of glassified $C_3A$ showed that it has low reactivity relative to crystallized $C_3A$, and also hydration reactivity of orthorhombic $C_3A$ was much lower than that of cubic $C_3A$ in 60 minutes. Potassium sulphate in the solution reduced the hydration reactivity of $C_3A$ . Evolution peaks of hydration heat examined by twin-type conduction micro-calorimeter showed that glassified $C_3A$ without $K_2O$ had secondary peak after 9 hours and $C_3A$ containing $K_2O$ after 12 hours. When crystallized $C_3A$ was hydrated, initial peaks of hydration heat were considerably high and there was no secondary peak for cubic $C_3A$ but the secondary peak of orthorhombic $C_3A$ appeared after 4 hours.

한국 석회석의 열분해특성 및 가열에 의한 상변화에 관한 연구

한기성,안기상,최롱,Han, Ki-Sung,Ahn, Ke-Sang,Choi, Long 한국세라믹학회 1983 한국세라믹학회지 Vol.20 No.1

The investigations have been carried out to study the characteristics of limestone using in Korean cement industry with prime interests in the dissociation and thermal phase changes of limestone between 90$0^{\circ}C$ and 140$0^{\circ}C$ The range of decomposition temperature of limestone was 840-87$0^{\circ}C$ and it was considered that the temperature was lowered by impurities in the limestone. The more the impurities and the finer the grain size of quartz in limestone the lower temperature was applied in forming $C_2S$ mineral the temperature of about 100$0^{\circ}C$. The major clinker minerals such as $C_3S$, $C_2S$, $C_3A$ and $C_4AF$ were formed in most of limestone when the firing temperature was up to 130$0^{\circ}C$.

혼합 cement의 개발 연구

한기성,Han Ki Sung 大韓窯業學會 : 韓國洋灰工業協會 1973 시멘트 심포지움 Vol.1 No.-

Cement industry in Korea, has made a remarkable progress in recent years and now annual production capacity is about 9,000,000 tons. However, this large amount of cement is only one kind of general portland cement type I, and it is urgent problem for ceme

김치에서 분리한 Lactobacillus plantarum LHC52의 항균활성과 요구르트의 관능성 연구

이승규,한기성,정석근,오미화,장애라,김동훈,배인휴,함준상,Lee, Seung-Gyu,Han, Ki-Sung,Jeong, Seok-Geun,Oh, Mi-Hwa,Jang, Ae-Ra,Kim, Dong-Hun,Bae, In-Hyu,Ham, Jun-Sang 한국축산식품학회 2010 한국축산식품학회지 Vol.30 No.2

The aim of our study was to develop a new starter culture for fermented milk. Polymerase chain reaction screening of 103 acid-producing isolates from Kimchi identified 72 Lactobacillus strains. The ability of the strains to inhibit the growth of the food-borne human pathogens (Escherichia coli, Salmonella Enteritidis, Staphylococcus aureus) was measured, using a conventional paper disk method. Among the 72 strains, strain LHC52 displayed potent antagonistic activity. Use of 16S rDNA sequencing and the API 50CHL system identified the strain as Lactobacillus plantarum and it was designated L. plantarum LHC52. Biochemical analyses revealed especially high antibacterial activity against E. coli. Yogurt produced using L. plantarum LHC52 did not show different microbiological and physicochemical properties compared to conventionally-prepared yogurt, implicating L. plantarum LHC52 as a useful, potently antibacterial starter culture for yogurt preparation.

티타늄琺瑯후릿트에 關한 硏究

이종근,한기성,Lee, Chong-Keun,Han, Ki-Sung 대한화학회 1957 대한화학회지 Vol.4 No.1

There are two problems to be solved by our efforts in the enamel frit. One is how we can cover the enamel frit thin with complete milk white as possible, and the other is how it can be, made resistant for chemicals than before one. The frit which can solved the two problems just mentioned above is titanium enamel frit. This frit has been developed in America after War Ⅱ, and now the research for concerning antimony frit into titanium frit is under development entirely. In order to develope the enamel industry in Korea, it is urgent problem to convert antimony frit into titanium frit. By the way the titanium frit is emulsified titanium oxide crystal which made through reheating the supersaturated solution of titanium oxide in the basis of glass. Unfortunately, there are many obscure points in active fact or which influence on its composition and characteristics yet. However, this task was tried for the first in Korea. As first step, the test was carried on the reference books, and we can be possible convert antimony frit into titanium frit as a result of this experiment. As a conclusion, for the purpose of developing the enamel industry in Korea, we studied that the research for converting antimony enamel frit which has been used popularly into titanium enamel frit which is more economic and resistant for chemicals. As a result of experiments, the following points concerning with titanium frit have become clearly. 1. It is better when the composition of titanium enamel frit has as following table.Man Duck San Silica 24 An Yang Feldspar 20 Borax 28 Sodium Nitrate 4 Cryolite 7 Calcium Carbonate 3.6∼1 Titanium Oxide 10 Calcium phosphate 0 ∼3.2 Calcium Fluoride 0∼1.8 Antimony Oxide 0∼0.5 2. The amount of $TiO_2$, to be added is $10%\;to\;12{%,\;CaF_2\;is\;under\;1.8%,\;P_2O_5\;is\;under\;1.6%,\;Sb_2O_3\;is\;under\;0.5%$. 3. In the titanium frit, the limit of iron oxide amount to be included is under 0. 5%. 4. Comparing the titanium enamel frit with antimony enamel frit not only the titanium frit can be savely 20.6% in the price of raw materials, but one time of glazing and heating process is omitted in each case, and it is known the titanium frit is more resistant for chemicals than antimony frit.

마유의 영양적 특성 및 생리활성 성분

장운기 ( Oun Ki Chang ),정석근 ( Seok Geun Jeong ),한기성 ( Gi Sung Han ),설국환 ( Kuk Hwan Seol ),박범영 ( Beom Young Park ),함준상 ( Jun Sang Ham ) 한국유가공기술과학회 2013 Journal of Dairy Science and Biotechnology (JMSB) Vol.31 No.1

Mare milk is gaining importance because of its nutritional characteristics and therapeutic properties, which enable its use as part of the diet of the elderly, convalescents, and newborn infants. This review describes the functional and bioactive components of mare milk, such as proteins, carbohydrates, and lipids, and the characteristics such as acidification and released free amino acids of fermented mare milk. The protein profile of mare milk differs from that of bovine milk but is similar to that of human milk. The salt and lactose content in mare`s milk is similar to that in human milk, but mare`s milk has a significantly lower content of fat. Whey protein concentration is higher and casein content is much lower in mare milk than in bovine milk. These health-promoting properties indicate that mare milk and its derivatives could become valuable foods for elderly consumers in the form of probiotic beverages. Protein allergies related to and the potential industrial applications of mare milk have also been discussed in comparison with those of bovine milk. Although mare milk has diverse advantages if used as a nutritional food and has positive effects on health, further studies are required to enable its use as a complete substitute for human milk or as a health food.

유제품 발효에서 유산균의 단백질 가수분해 시스템

장운기 ( Oun Ki Chang ),설국환 ( Kuk Hwan Seol ),김민경 ( Min Kyung Kim ),한기성 ( Gi Sung Han ),정석근 ( Seok Geun Jeong ),오미화 ( Mi Hwa Oh ),박범영 ( Beom Young Park ),함준상 ( Jun Sang Ham ) 한국유가공기술과학회 2012 한국유가공기술과학회지 Vol.30 No.2

Lactic acid bacteria (LAB) have been used as starter cultures in the manufacturing processes of fermented dairy products such as cheese and yogurt. LAB have a proteolytic system to use the nitrogen source from milk for their growth. The proteolytic system involved in casein utilization provides cells with essential amino acids during growth in milk and is also of industrial importance, because of its contribution to the development of the organoleptic properties such as flavor of fermented milk products. In the most extensively studied LAB, Lactococcus lactis, the main features of the proteolytic system comprise 3 groups. The first is proteinase, which initially cleaves the milk protein to peptides. The second group consists of transport systems for the internalization of oligopeptides, which are involved in the cellular uptake of small peptides and amino acids. The third group, peptidases in the cell, cleaves peptides into smaller peptides and amino acids. This review is to provide the information about the proteolytic system of LAB.

포틀랜드 시멘트 클린커 광물조성의 X선구절에 의한 정량분석

장세경,이전,한기성,Chang, Se-Kyung,Rhee, Jhun,Han, Ki-Sung 한국세라믹학회 1986 한국세라믹학회지 Vol.23 No.2

In this investigation x-ray diffraction method was mainly studied for quantitative analysis of clinker mineral composition. And also optical microscopic observation and Bogue calculation method were applied to compare with the x-ray diffraction method. In the procedure of x-ray diffraction analysis graphite monochromator automatic divergence slit and spinner for sample holder were used for minimizing the error due to the operation of the equipment. Especially the separation of overlapped peaks were proceeded by micro-processor automatically. The results of x-ray diffraction method for synthesized clinker were consistent with the Bogue value and the results of optical microscopic observation. However the results of quantitative analysis of mineral composition or commercial clinker containing solid solution of minor component were different from the Bogue value. On the other hand they agreed reasonably well with results of the optical mic-roscopic observation.

지르코니아 인성강화 알루미나 분체의 제조 및 소결

이전,최상욱,한기성,김승태,Rhee, Jhun,Choi, Sang-Wook,Han, Ki-Sung,Kim, Seung-Tae 한국세라믹학회 1992 한국세라믹학회지 Vol.29 No.3

Zirconia-toughnened alumina(ZTA) powders that were uniformly coated with zirconia and yttria on the surface of alumina particles were prepared in order to inhibit the grain growth of alumina. Alumina particles were ultrasonically dispersed in the ethanol solution of Zr-n-propoxide, and then the Zr-alkoxide was hydrolyzed. Hydrated zironia as thin film was stabilized to tetragonal crystalline form by doping yttria as a stabilizer. The prepared ZTA powders had the good sinterability even at the lower temperature. As a result, the sintered bodies showed the enhanced fracture toughness compared with pure alumina. The relative density and fracture toughness(KIC) of the ZTA bodies sintered at 1550$^{\circ}C$ were 98% and 5 MPa$.$m1/2 respectively.

고노슬라그의 이용에 관한 연구(I) (슬라그유리의 결정성장)

이준,지응업,한기성,최상욱,Rhee, Jhun,Chi, Ung-Up,Han, Ki-Sung,Choi, Sang-Wook 한국세라믹학회 1978 한국세라믹학회지 Vol.15 No.3

The batch compositions and physical properties of slag-ceramics were studied with respect to their formability from the molten state and conditions of nucleation and crystal growth treatment. The selected batch compositions for nucleation and growth studies were slag, 56%; silica sand, 28%; $Na_2O+MgO$, 8% and $TiO_2+$chromite, 8%. The optimum nucleation condition was the temperature of 75$0^{\circ}C$ with 6 hrs. holding time and the optimum growth condition was the temperature 975$^{\circ}C$ with zero holding time. The slag-ceramics prepared under the above conditions showed the best developed microtexture. The grown crystals were identified as diopside with the average grain size of 5.7$\mu\textrm{m}$, and the amount of crystal grown were about 53% by weight. The prepared specimens of slag-ceramics showed the microhardness, 793kg/$\textrm{mm}^2$; MOR, 1,050 kg/$\textrm{cm}^2$ and thermal expansion coefficient, $85{\div}10^{-7}$cm/cm/$^{\circ}C$($25^{\circ}C$~$700^{\circ}C$).