• 제목/요약/키워드: preparation process

검색결과 2,648건 처리시간 0.037초

Ammonium Chloride Process 및 Ammonium Nitrate Process를 이용한 고순도 탄산칼슘의 제조 (Preparation of Calcium Carbonate with High Purity by using Ammonium Chloride Process and Ammonium Nitrate Process)

  • 강미숙;소관순;신동화
    • 한국식품위생안전성학회지
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    • 제19권4호
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    • pp.203-208
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    • 2004
  • 꼬막, 참굴, 바윗굴 및 가리비 등 폐기되는 몇 종의 패각류를 이용하여 칼슘 보강용 식품 첨가제의 원료로써 사용 할 수 있는 고순도의 탄산칼슘을 제조하고자 하였다. 꼬막 패각을 $900^{\circ}C$에서 5시간 회화한 회화분의 칼슘 함량이 $64.9\%$로 가장 높게 나타났으며, 가리비 $62.5\%$, 참굴 $62.4\%$, 바윗굴 $61.5\%$ 순이었다 백색도는 가리비 패각 회화분의 경우 81.6-85.8로서 패각류 중 가장 높았다. 꼬막 패각 회화분$(Ca\;39.92\%)$에 ammonium chloride process(ACP)와 ammonium nitrate process(ANP)법을 적용하여 제조한 $CaCO_3$의 Ca 함량은 $40.03-40.04\%$로 높아졌고, ANP법에 의해 제조한 pH 조정 시료의 경우가 $40.04\%$로서 가장 높았으며, 이 방법들에 의해 불순물이 거의 대부분 제거되는 것으로 나타났다. ACP법과 AMP법에 의해 제조한 $CaCO_3$의 백색도는 101.0-101.5로 매우 우수하였으며, 칼슘보강용 식품첨가제로서 사용될 가능성이 충분하다고 판단된다.

초임계 ASES 공정으로 제조된 Vitamin-C 포접복합체의 안정성 평가 (Stability Evaluation of Vitamin-C Inclusion Complexes Prepared using Supercritical ASES Process)

  • 양준모;김석윤;한지현;정인일;유종훈;임교빈
    • KSBB Journal
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    • 제21권2호
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    • pp.157-163
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    • 2006
  • 본 연구에서는 초임계 ASES 공정을 이용하여 인체내 및 피부에 여러 가지로 유익한 대표적 생리활성물질인 Vitamin-C의 불안정성을 극복하기 위하여 HP-${\beta}$-CD와의 포접복합체를 제조하여 수용액상에서의 안정성을 분석하였다. X-선 회절을 이용한 Vitamin-C와 HP-${\beta}$-CD의 결정성 분석으로 초임계 ASES 공정을 통하여 포접복합체가 용이하게 형성될 수 있음을 확인하였다. HP-${\beta}$-CD가 Vitamin-C의 안정성을 향상시키는 방법으로 이용될 수 있음을 확인하였으며, $25{\pm}0.1^{\circ}C$의 온도를 유지한 pH 7.0의 50 mM 인산완충용액 상에서 순수한 Vitamin-C, 물리적인 혼합물 및 용매증발법과 초임계 ASES 공정을 이용하여 제조된 포접복합체의 Vitamin-C 겉보기 1차 분해 속도 상수는 각각 $1.45{\times}10^{-2}h^{-1},\;1.41{\times}10^{-2}h^{-1},\;1.34{\times}10^{-2}h^{-1},\;0.20{\times}10^{-2}h^{-1}$로 초임계 ASES 공정으로 제조된 포접복합체의 경우 Vitamin-C의 안정성이 매우 크게 향상되는 것을 확인하였다.

자동차 조립 공정계획을 위한 Web 기반 협업시스템 (Web-based Collaborative Process Planning System for the Automotive General Assembly Shop)

  • 노상도;박영진;공상훈;이교일
    • 산업공학
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    • 제16권3호
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    • pp.375-381
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    • 2003
  • To ensure competitiveness in the modern automotive market, process planning should be performed concurrently with new car developments. In automotive general assembly shops, thus, new business workflows and supporting environments are inevitable to reduce the manufacturing preparation time in developing a new car in the manner of concurrent and collaborative engineering. Since complete process planning for a whole general assembly system is a huge and complex job, several process planners should execute their planning jobs and share information. Therefore, each planner should provide others with his/her results with continuous on-line communication and cooperation. In this research, a web-based system for concurrent and collaborative process planning for automotive general assembly is developed. By using this system, savings in time and cost of assembly process planning are possible, and the reliability of the planning result is improved.

Reactive Extrusion of Starch-g-Polyacrylonitrile in the Preparation of Absorbent Materials

  • Yoon, Kee-Jong;Carr, M.E.;Bagley, E.B.
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 1990년도 제2차 학술발표초록집
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    • pp.8-8
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    • 1990
  • A new method for the graft polymerization of acrylonitrile onto starch is presented. Graft polymerization of acrylonitrile onto starch and the subsequent hydrolysis in sodium hydroxide solution to prepare absorbents is well known. This process has been utilized to produce the commercial product, Super Slurper. In a typical batch process, ~5% starch in water mixture is gelatinized at $95^{\circ}C$ under stirring for 1 hour then cooled to room temperature. The graft polymerization itself is carried out for approximately 2 hours at $25~30^{\circ}C$ on the gelatinized starch by eerie ion initiation. In this study, graft polymerization of acrylonitrile onto starch via a reactive extrusion process which is a continuous, efficient process is described. Initial concentration of starch in water is 35% and the reaction temperatures are between $50~80^{\circ}C$. However, the most significant difference in the reactive extrusion process is the short time in which the graft polymerization takes place. Preliminary results on the properties of graft polymerization products obtained from the reactive extrusion process are compared to those obtained from the batch process as well as the absorbency of the hydrolyzed samples. Absorbent material has also been prepared by sequential grafting and saponification in the extruder followed by a 2 hour heat treatment of the extrudate in an air circulated oven at $100^{\circ}C$.

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변동성을 고려한 탑재프로세스 모델링과 시뮬레이션에 관한 연구 (A Study on the Erection Process Modeling and Simulation considering Variability)

  • 임현규;이용길;김병철;우종훈
    • 대한조선학회논문집
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    • 제53권2호
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    • pp.101-107
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    • 2016
  • Generally, the shipbuilding industry has finite resources and limited workspace. Due to finite resources, limited workspace and state of block preparation, erection process in shipbuilding industry is frequently delayed than erection process scheduling which is planned at long-term plan stage. In this study, considering variability of block reserve ratio, the degree of delay in real erection process is measured and compared to scheduling which is planned at long-term plan stage in shipbuilding industry including finite capacity and variative lead time. Also, the erection process scheduling which has minimum lead time can be checked through simulation. The results of this study could be improved the accuracy of erection process scheduling by checking the main event compliance ratio by block reserve ratio and calculating the optimum erection pitch for the main event compliance.

수의의 금기에 관한 고찰 (An Inquiry into the Taboo of the Burial Shroud)

  • 남민이
    • 복식문화연구
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    • 제7권3호
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    • pp.50-57
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    • 1999
  • Folk belief, which originated with the rise of human existence is a fundamental and comprehensive mode of living that reflects sociocultural conditions. Adherents of folk belief accept a certain thing to be true and real without scientific authority and absolute certainty. Taboo can be seen as a king of folk belief. The object of this study is to examine the taboos in relation to the manufacturing process and the quality of the shroud and to shrouding customs. I will also try to find out the meaning and significance in this. Through this task, I hope to contribute to the enhanced understanding of the cultural characteristics, the spiritual life, and the views on after life of the Korean people. In Korea, it is considered to be propitious to prepare the shroud on the intercalary month of the leap year , as it allows one to enjoy longevity healthy and sound. Moreover, as this belief gives credence and repose while preparing for the “final departure”, this custom is relatively well observed. From the taboo concerning leap months, we infer that death as viewed as a commencement of a new life, which reveals a positive view on afterlife. This can be seen as a return to the origin of anti-universal space in this “bonus” month of anti-universal time. Taboos on the manufacturing process of the shroud is related to the belief that it allows the deceased to go the nest world without any hesistation or disturbances. This symbolizes the immortality of the human soul: I. e. that the human spirit does not end in this world but continues on to the next. Taboos concerning the preparation process of the shroud as well as various other taboos are related to the belief that preparation for the shroud should be done in sincerity and secredness with a thoughtful consideration for the deceased. This can be perceived as an implication to sanctity for the dead.

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용융 압출 발포에 의한 폴리락틱산 지지체 가공 (Preparation of Poly(L-lactic acid) Scaffolds by Melt Extrusion Foaming)

  • 이종록;강호종
    • 폴리머
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    • 제29권2호
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    • pp.198-203
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    • 2005
  • 용융 압출 발포에 의하여 폴리락틱산(PLLA) 지지체를 제조하고 발포 조건이 지지체의 구조와 기계적 특성에 미치는 영향을 살펴보고 이를 염 추출법에 의하여 제조된 지지체와 비교하였다. 발포제를 함유한 PLLA 용융체가 압출기 및 다이에서 체류하는 시간이 발포제의 무게를 최대로 감소시키는 시간과 일치하여야 최적의 PLLA 지지체의 구조를 얻을 수 있음을 확인하였다. PLLA지지체의 구조를 유지하기 위해서는 발포제의 함량을 $10\;wt\%$ 이하로 조절해야 하며 PLLA 지지체의 다공도는 PLLA의 압출기에서의 체류시간에 가장 큰 영향을 받음을 알 수 있었다. 용융 압출 발포에 의하여 얻어진 지지체는 일반적으로 염 추출법에 의하여 제조된 지지체보다 다소 낮은 다공도를 갖지만 발포 조건의 조절에 의하여 적절한 다공 크기와 다공의 연결성을 가지며 동시에 우수한 기계적 특성을 가져 경조직 재생(hard tissue regeneration)용으로 사용이 가능할 것으로 사료된다.

새로 개발한 조월견방부제 ″쉬세요(Swi-Se-Yo)″의 효과에 관하여 (Study on the Effect of a New Antiseptic Preparation ″Swi-Se-Yo″ on the Carry-Over Cocoons in Silk Reeling Process)

  • 이장낙;정태암;송기언;하정근
    • 한국잠사곤충학회지
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    • 제18권2호
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    • pp.107-110
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    • 1976
  • In silk reeling process the carry-over cocoons must be submerged in the reeling baths filled with reeling water and left until reopening the operation. Under the detention the carry-over cocoons are apt to decay without any antiseptic treatment. Thus an useful antiseptic for the cocoons is urgently needed, and various antseptic agents have been tested for their applicability to the process. However, such an useful agent has not been developed yet. Formalin has been the only chemical used for antisepticizing carry-over cocoons, although it has many defects as the antiseptic for the cocoons. In these circumstances, recently we newly prepared an antiseptic useful for preventing the carryover cocoons from decaying. We named the new antiseptic preparation "Swi-Se-Yo." The Korean term "Swi-Se-Yo" literally means "please take a rest". Through a series of experiments with Swi-Se-Yo we obtained the following results: 1) Swi-Se-Yo, in 0.05% aqueous solution, exerted a good antiseptic effect on the boiled Cocoons submerged in the reeling baths and the effect lasted for 45 hours. The duration of the effect is about two times longer than that of Formalin. 2) The percentage of cocoon reel ability of the carry-over cocoons treated with Swi-Se-Yo was 6% higher than that of Formalin and was equal to that of flowing cold water. 3) The percentage of raw silk yield of the carry-over cocoons treated with Swi-Se-Yo was almost equal to that of Formalin and to that of flowing cold water. 4) The quality of raw silk of the carry-over cocoons treated with Swi-Se-Yo is the same as that of flowing cold water. Besides the above favourable results, Swi-Se-Yo has many advantages as an antiseptic. Chemically it is very stable. Its antimicrobial action is very strong and the spectrum is very broad. It can be available in water-soluble powder and in small bulk. And it is not harmful to human and domestic animals. Considering these profitable properties of Swi-Se-Yo, it will have a good reputation as a carry-over cocoon antiseptic. (The chemical composition and manufacturing method of Swi-Se-Yo will be published in the near future.)

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실업계 고등학생의 금연프로그램 운영 효과에 관한 연구 - 범이론적 모형(Transtheoretical Model)을 중심으로 - (A Study on the Effects of Vocational High School Students' Smoking Cessation Program Operation - Focused on the Transtheoretical Model -)

  • 이혜숙
    • 한국보건간호학회지
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    • 제18권2호
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    • pp.205-217
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    • 2004
  • This study conducted a survey with the 67 students who are in their 2nd year at 3 vocational high schools. The researcher of this study developed and operated the smoking cessation program based on the Transtheoretical model. To evaluate the effects, experiments were repeatedly done. The data were collected from June 21, 2004 till July 9, 2004. The survey was done based on the questionnaire-interview before and after education. The collected date was computerized by using SPSS-WIN 10.0 program. The results are as follows: Firstly. before education, the smoking cessation stage of change shows precontemplation stage $37.3\%$, preparation stage $37.3\%$, and contemplation stage $25.4\%$ respectively. However, after education it shows preparation stage $44.8\%$, action stage $25.4\%$, contemplation stage $19.4\%$, precontemplation stage $10.4\%$. The positive result was $62.7\%$ and smoking cessation stage of change made a 0.9 step increase. Secondly, process of change rose in all the areas except helping relationship. It also shows statistical improvement in all the fields except the dramatic relief of the experiential process, the helping relationship of behavioral process and stimulus control Thirdly, negative affective situation temptation, positive social situation temptation, and habitual strength temptation's average points decreased but showed statistical differences. Weight control temptation's average points decreased after education but didn't show statistical differences. Self efficiency increased measurably after education. Fourthly, concerning the social pros and coping pros caused by smoking, the average points were low after education and showed statistic decrease. As for the cons due to smoking, the average points increased but didn't show any statistical differences. In conclusion, thanks to the smoking cessation program applied by the Transtheoretical model, the smoking rate of vocational high school students became low and their smoking temptation also dropped considerably. In conclusion, while the pros for smoking were lessened, its corns were heightened through the educational awareness offered by this program.

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Environmentally Friendly Preparation of Functional Nanomaterials and Their Application

  • Lee, Sun-Hyung;Teshima, Katsuya;Endo, Morinobu;Oishi, Shuji
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2010년도 춘계학술발표대회
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    • pp.5.1-5.1
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    • 2010
  • One of the most important environmental problems is global warming. Global warming is caused by increase in the amounts of water vapor, methane, carbon dioxide and other gases being released into the atmosphere as a result of the burning of fossil fuels. It has thus become important to reduce fossil fuel use. Environmentally friendly preparation of functional materials has, therefore, attracted much interest for environmental problems. Furthermore, nature mimetic processes are recently been of great interest as environmentally friendly one. There have been many studies on fabrication of various functional nanocrystals. Among various nanocrystal fabrication techniques, flux growth is an environmentally friendly, very convenient process and can produce functional nanocrystals at temperatures below the melting points of the solutes. Furthermore, this technique is suitable for the synthesis of crystals having an enhedral habit. In flux growth, the constituents of the materials to be crystallized are dissolved in a suitable flux (solvent) and crystal growth occurs as the solution becomes critically supersaturated. The supersaturation is attained by cooling the solution, by evaporation of the solvent or by a transport process in which the solute is made to flow from a hotter to a cooler region. Many kinds of oxide nanocrystals have been grown in our laboratory. For example, zero- (e.g., particle), one- (e.g., whisker and tube) and two-dimensional (e.g., sheet) nanocrystals were successfully grown by flux method. Our flux-growth technique has some industrial and ecological merits because the nanocrystal fabrication temperatures are far below their melting points and because the used reagents are less harmless to human being and the environment.

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