• 제목/요약/키워드: mixed salt

검색결과 415건 처리시간 0.025초

스퀴즈캐스팅용 Salt Core의 제조 및 용탕침투성에 관한 연구 (A Study on the Fabrication Process and Melt Infiltration of Salt Core in Squeeze Casting Method)

  • 김기배;노상우;이호인;남태운
    • 한국주조공학회지
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    • 제17권4호
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    • pp.402-410
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    • 1997
  • Developing a salt core for squeeze casting process, two different salt cores(pure salt core and mixed salt core) were fabricated and investigated. Pure salt core was composed of 100% NaCl and mixed salt core was made by mixtures of NaCl with MgO(1%), $Na_2B_4O_7$(2%), and talc(1%) as a binder or a strengthening agent. Salt cores were compacted to various theoretical density, heat treated, and then squeeze-cast with molten Al alloy(AC8A). The compression strength of salt cores were measured and the squeeze-cast products were examined for shape retention, infiltration of molten metal into the cores, and microstructures. The shape of salt core compacted at above 75% of the theoretical density was maintained stably. The higher theoretical density of salt cores gave higher compression strength, and the compression strength of mixed salt core was higher than that of pure salt core. Namely at 90% theoretical density, the compression strength of mixed salt core was $6.3 kg/mm^2$, compared to $4.6 kgmm^2$ for pure salt core. At a squeeze casting pressure of $1000 kg/cm^2$, molten Al alloy was infiltrated into pure salt core of under 85% of the theoretical density. At squeeze casting pressure of $1000 kg/cm^2$, only mixed salt core above 90% of the theoretical density were valid, but the shape of the core was altered in the case of pure salt core at 90% of theoretical density. A key factor for developing a salt core for squeeze casting process was estimated as the ultimate compressive strength of salt core.

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발효과채쥬스의 제조 및 특성에 관한 연구 (A Study on the Preparation and Characterstics of Fermented fruit-Vegetable Juice)

  • 김유경;배영희;윤선
    • 한국식품조리과학회지
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    • 제6권4호통권13호
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    • pp.59-68
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    • 1990
  • Juices prepared from carrots, apples, and mandarin oranges were fermented with Leuconostoc mesenteroides or along with Saccharomyces cerevisiae. The pH of the fermented juices was not found significantly different between the mixed and single-cultured groups. The juices containing 0.5% NaCl had lower pH than the groups without 0.5% NaCl. The final pH of the single-cultured gruops was the highest among the sample groups. However, reducing sugar content of the mixed-cultured groups was lower than that of the single-cultured groups. The viable cells of the mixed-cutured groups were remarkably increased until 3 days of storage, and after 6 days they were gradually decreased. The results of the sensory evaluation demonstrated acidic, salty and alcoholic flavors were significantly different among the groups. The single-cultured group without salt was significantly more acidic than the non-pasteurized control group. The mixed-cultured group with salt was significantly more alcoholic than the group without salt and control groups. The non-pasteurized control group was significantly more homogeneous than the mixed-cultured groups and single-cultured group with salt. Preference ranking test showed that flavor and overall acceptability of the fermented juices was significantly different among the groups. Flavor of the single-cultured group without salt was found significantly better than those of the groups with salt. With the respect of overall acceptability, the single-cultured group without salt was significantly more acceptable than the non-pasteurized control group and the mixed-cultured group with salt.

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염화마그네슘의 용융염전해 연구 (Fused Salt Electrolysis of Magnesium Chloride)

  • 이후인
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.546-547
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    • 2007
  • Magnesium is widely used as a lightweight alloy for car engine components and case of cellular phone. Extraction technologies of magnesium are divided to fused salt electrolysis process and thermal reduction process. In this study, electrolysis magnesium is prepared by fused salt electrolysis process with magnesium chloride. We compared two kinds of mixed salt at 7V. As a result, 47% of current efficiency was obtained by electrolyzing KCl/NaCl/$MgCl_2$ mixed salt bath at $760^{\circ}C$, and purity of the prepared magnesium was over 98%. With this study, we can scale up fused salt electrolysis device and accumulate basic data which will be needed for designing an electrolysis cell.

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고강도 콘크리트 강도별 염분확산계수 및 편차에 관한 연구 (A Study on Salt Diffusion Coefficient and Deviation by Strength of High-Strength Concrete)

  • 박동천;석원균;전현수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2022년도 가을 학술논문 발표대회
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    • pp.117-118
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    • 2022
  • High-strength concrete is used for building durability on the coast. It is common to order and produce the concrete from several ready mixed concrete companies. The concrete in Busan was also commissioned by 12 ready mixed concrete companies. The compressive strength and salt diffusion coefficient were measured. The average value and deviation were analyzed.

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$Al_2O_3$로 피복시킨 세라믹 복합분체의 제조 및 특성 : (I) 피복용 혼합 알루미늄 염 용액의 가수분해 (Preparation and Characteristics of Ceramic Composite Powders Coated with $Al_2O_3$: (I) Hydrolysis of Mixed Aluminum Salt Solution for Coating)

  • 현상훈;정형구
    • 한국세라믹학회지
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    • 제27권7호
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    • pp.851-860
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    • 1990
  • The hydrolysis-precipitation reaction of mixed aluminum salt solutions of aluminum sulfate, aluminum nitrate, and urea has been investigated to obtain narrow-sized and unagglomerated fine spherical precipitates of aluminum hydroxide required for coating core particles. The hydrolysis-precipitatin reaction could be controlled to be appropriate to coating processes by usign urea as a pH control-agent. As the concetration of total Al3+ ion and the molar ratio of SO42-/Al3+ in starting solutions became smaller and also as the vol. ratio of water/solution for hydrolyzing mixed aluminum salt solution became larger, the morphology of precipitates tended to be more unagglomerated and spherical, while their size(0.5longrightarrow0.05${\mu}{\textrm}{m}$) to be smaller. The optimum hydrolysis condition for coating processes was to hydrolyze the mixed aluminum salt solution, in which the molar ratio of SO42-/Al3+ was 0.75, while the amount of water corresponding to the vol. ratio of water/solution of 15. The precipitate was the aluminum hydroxide which sulfate ions were strongly adsorbed on and the maximum yield in the hydrolysis-precipitation reaction was about 20%.

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히스토그램 및 국부 마스크의 화소 정보를 이용한 복합잡음 제거 (Mixed Noise Removal using Histogram and Pixel Information of Local Mask)

  • 권세익;김남호
    • 한국정보통신학회논문지
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    • 제20권3호
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    • pp.647-653
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    • 2016
  • 최근, 디지털 영상처리는 방송, 통신, 컴퓨터 그래픽, 의학 분야 등에서 많이 응용되고 있으며, 일반적으로 영상 데이터는 전송하는 과정에서 잡음이 발생한다. 이에 따라 영상에 첨가되는 잡음을 제거하기 위한 연구가 활발히 진행되고 있다. 영상에 첨가되는 잡음에는 다양한 종류가 있으며, salt and pepper 잡음, AWGN, 복합잡음이 대표적이다. 따라서 본 논문에서는 영상에 첨가된 복합잡음의 영향을 완화하기 위하여 잡음 판단 후, salt and pepper 잡음은 히스토그램과 기존의 공간 가중치를 이용하여 처리하고, AWGN은 국부 마스크의 화소 정보를 이용하여 가중치를 설정하고 처리하는 영상복원 필터 알고리즘을 제안하였다. 제안한 알고리즘은 salt and pepper 잡음(P=50%) 및 AWGN(${\sigma}=10$)에 훼손된 Lena 영상을 적용하여 처리한 결과, 기존의 CWMF, A-TMF, AWMF에 비해 각각 7.06[dB], 10.90[dB], 5.97[dB] 개선되었다.

열-염분 이중확산계에 관한 실험적 연구 (An Experimental Study on the Double Diffusive Thermohaline System)

  • 박희용;임경빈
    • 태양에너지
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    • 제6권2호
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    • pp.15-21
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    • 1986
  • In this study, an experimental double diffusive thermohaline system heated from below was constructed and the phenomena of each layer developed in the system were observed. The experiment was performed with the initial salt concentration gradient of $-436.2kg/m^4$ and the net heat flux of approximately $176w/m^2$. An electroconductivity-temperature probe was made and used for the measurements of salt concentration. As the result of this study, it was found that the salt concentration decreased in the bottom mixed layer and increased in the top mixed layer during the experiment while the salt concentration gradient in the diffusive layer unchanged. It was also found that the interfacial boundary layers were due largely to variations in salt concentration rather than temperature.

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설계기준 압축강도별 레미콘의 염소이온 확산 특성평가 (Chloride Ion Diffusion for Ready Mixed Concrete)

  • 박동천;김용로
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2018년도 추계 학술논문 발표대회
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    • pp.149-150
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    • 2018
  • The RC buildings which are constructed on the seaside are followed by KBC(2016) to achieve the minimization of durability damage. To control the corrosion of the reinforced steel bar by salt attack, W/C should be under 0.4 and specified concrete strength is more than 35MPa in the concrete/building construction standard specification. Ready mixed concretes which have usually include the admixtures in Busan were tested to certify the salt attack durability. In the same specified concrete strength, remarkable salt attack durability was evaluated in comparison to OPC.

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염화물을 함유한 제설제가 콘크리트의 열 특성과 미끄럼저항성에 미치는 영향에 관한 연구 (Effect of Chloride-containing Deicer on the Thermal Charateristics and Skid Resistance of Concrete)

  • 이병덕;윤병성
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.509-512
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    • 2004
  • This research is targeting that estimate the effect on cement concrete pavement with type of chloride deicers. In order to this study objective, when chloride deicers were spread on road surface, thermal characteristics test was conducted. Also, skid resistance test according to types and concentration of chloride deicier, road surface conditions were investigated. As a test results, thermal characteristics with kind of chloride deicier could know that sodium chloride(NaCl) is exothermic reactive material, calcium chloride$(CaCl_2)$ is endothermic reactive material. And, in case of mixed salt of the calcium and sodium chloride, it could know that can change to the exothermic or endothermic reaction according to dosage ratios. Skid value by British Pendulum Tester(BPT) has shown that it is seldom difference between the types($CaCl_2$, NaCl, mixed salt) and solution concentrations(0.5, 0.8, 1.0, 4.0, $10\%$) of chloride deicier comparing with tap water except mixed salt($10\%$ solution concentration).

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제조방법을 달리한 겹장의 당, 아미노산 분석 및 관능 특성에 관한 연구 (Study on Sugar, Amino Acid, and Sensory Characteristics in Traditional Korean Gyupjang (Soy sauce) According to Different Methods)

  • 김경민;이지윤;정낙원
    • 한국식생활문화학회지
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    • 제31권4호
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    • pp.348-356
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    • 2016
  • The purpose of this study was to investigate the chemical contents (sugar, nitrogen, and amino acids) and sensory characteristics of traditional soy sauce according to three different methods. The samples were taken from four different periods (0, 20, 40, and 60 days after fermentation). Total sugar contents increased in all groups according to ripening period, and Gyupjang (G) showed the highest sugar content among the groups. Total nitrogen and amino acid contents of all groups increased after 60 days of ripening, and Gyupjang (G) and Gyupjang mixed with salt water (SG) had higher total nitrogen content compared to Chungjang (S) at the same period. The results from the sensory evaluation show that preferable sensory characteristics, such as color preferences, sweetness, umami taste, and overall preference, were significantly higher in Gyupjang (G) and Gyupjang mixed with salt water (SG) than in Chungjang (S). Preferable sensory characteristics had significantly high positive correlation with most amino acids, total nitrogen, and sugar contents, except for glutamine. Based on the significant difference in preferable sensory characteristics between Gyupjang mixed with salt water (SG) and Chungjang (S), Gyupjang mixed with salt water (SG) can be used to improve sensory characteristics. This research implies that adding salt water during the manufacturing Gyupjang process is advisable to yield high quality soy sauce.