• 제목/요약/키워드: Salt concentration

검색결과 1,750건 처리시간 0.022초

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

  • 박희용;임경빈
    • 태양에너지
    • /
    • 제6권2호
    • /
    • pp.15-21
    • /
    • 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.

  • PDF

간장에서 분리한 Zygosaccharomyces rouxii의 휘발성 유기산 생성에 미치는 식염농도의 영향 (The Effect of Salt Concentrations on the Production of Volatile Organic Acids by Zygosaccharomyces rouxii, a Soy Sauce Yeast)

  • 권동진;하덕모
    • 한국미생물·생명공학회지
    • /
    • 제22권2호
    • /
    • pp.120-125
    • /
    • 1994
  • By using a synthetic medium simulated on the amino acid composition of soybeam, the effect of salt concentrations on the production of volatile organic acid by the strains of Zygosaccharomyces rouxii So-3101, a soy sauce yeast, was studied at the concentrations of 12.5, 18.0, 22.0 and 28.5% NaCl. The growth, consumption of glucose, and production of alcohol, total acid and volatile organic acid, showed the highest values at a concentration of 12.5% NaCl, and those values were decreased with an increase in the salt concentration. The ratio of volatile organic acid to total organic acid was remained at approximately the same level within the range of salt concentrations between 12.5~22.0%, whereas the ratio was decreased at a salt concentration of 28.5%. After incubation for 16 days, 8 volatile organic acids, i.e. acetic, propionic, n-butyric, isobutyric, isovaleric, isocaproic, n-caproic, and heptanoic acids, were detected by gas chromatography. Among the volatile organic acids, acetic acid was produced in the appreciable amiunt and its ratio to the other volatile acids was increased with an increase in the salt concentration.A small amount of isocaproic, propionic, isobutyric and isovaleric acids were produced, and n-caproic, n-butyric and heptanoic acids were detected only at the lower salt concentration.

  • PDF

배추의 소금절임중 엽신의 휘임도 변화 (Changes in Curve-Angle of Blade during Salting of Chinese Cabbage)

  • 김미경;김일두;김순동
    • 한국식품저장유통학회지
    • /
    • 제4권2호
    • /
    • pp.163-171
    • /
    • 1997
  • This study was undertaken to investigate changes m curve angle of Chinese cabbage blade during salting at various concentration(10, 15, 20, 25%) of salt to evaluated salting degree by curve angle during salting at 20$^{\circ}C$. Salt concentration of brine, the amount of water elution, salt penetration of the tissue(salt concentration of Chinese cabbage), weight loss and texture were investigated. Correlation relation between the above factors and curve angle were determined. The curve angles by method of holding the edge of the Chinese cabbage blade was measured. The curve angles of the mesophyll were proportional to salting time and salt concentration, but slope of line equation showed higher than that of mid-rib. The ideal method of salting evaluation by curve angle was MCA-MRC (the measuring curve angle of mid-rib C) at each concentration of salt. The results of curve angle when reached 3% salt of Chinese cabbage tissue calculated by MCA-MRC at 10, 15, 20 and 25% salting were 57$^{\circ}$, 43$^{\circ}$, 36$^{\circ}$, and 33$^{\circ}$, respectively. And salting times calculated by the same conditions were 19, 12.5, 9.1 and 4.4hours, respectively.

  • PDF

고분자전해질의 LbL multilayering 시 pH와 염 농도 조건에 따른 섬유의 전기화학적 특성 (Electrochemical Properties of Pulp Fiber with LbL Multilayering by Polyelectrolyte at the Different pH and Salt Concentration)

  • 류재호;이성린;진성민;윤혜정
    • 펄프종이기술
    • /
    • 제40권4호
    • /
    • pp.59-65
    • /
    • 2008
  • Electrochemical properties of pulp fiber could be modified by LbL(Layer-by-Layer) multilayering. Salt concentration and pH affect the conformation and ionization degree of polyelectrolyte. In this study, therefore, we intended to evaluate the effect of pH and salt concentration in polyelectrolyte multilayering on the electrochemical properties of pulp fiber. The pH of the stock was varied to 4, 7, and 10. Salt concentration was controlled at 0.001, 0.003, and 0.005 M of NaCl. Higher zeta potential was obtained when pulp fibers were multilayered at the condition of higher pH and higher salt concentration. The final zeta potential of pulp fiber after multilayering was dependent on the adsorption ratio of polyelectrolyte and the initial zeta potential of fibers.

복합조직강의 부식피트 성장특성에 미치는 식염수농도의 영향 (Influence of Salt Solution Concentration on Corrosion Pit Growth Characteristic of Dual Phase Steel)

  • 오세욱;강호민;김태만;도영민
    • 한국해양공학회지
    • /
    • 제2권2호
    • /
    • pp.78-86
    • /
    • 1988
  • In order to investigate the corrosion pit occurrence and growth characteristic of M.E.F.(martensite encapsulated islands of ferrite) dual phase steel was made with a suitable heat treatment of raw material(SS41), a corrosion fatigue test was performed under rotary bending in the salt solution having a concentration from 0.01 wt percent to 3.5 wt percent. The fatigue strength of dual phase steel was remarkably decreased with an increase in concentration of salt solution; approximately from 63% to 80% in case of dual phase steel and from 40% to 71% in case of raw material. Corrosion pit occurred in the martensite phase and fatigue cracks from corrosion pits were selectively propagated in martensite phases. In the observation of corrosion pits at the origin of fatigue cracks, it had been found that corrosion pits were grown into hemispherical pits and a/c(the surface diameter, 2c and the depth, a of corrosion pit)was about 1.0-1.5regardless of the variation of salt solution concentration. The difference of corrosion pit depth growth rate was increased with an increase in concentration of salt solution according to an increase in stress level.

  • PDF

시설재배지 토양의 염류축적 현상과 제염방안 (Effectivess of a salt extraction technique in soils under protected cultivation)

  • 홍성구;이남호;전우정;황한철;김진태
    • 한국농공학회:학술대회논문집
    • /
    • 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
    • /
    • pp.447-453
    • /
    • 1999
  • Salt accumulation is one of themajor problems in soils under protected cultivation . Since protected cultivation does not have rainfall or excessive irrigation, salt accumulaiton inthe soils is inevitable. In this study, characteristics of salt accumulation in soil column were ivestigated, and a salt-extracting method was tested to see its effectiveness. The results showed that the concentration of salt in top soil layers increased and electrical conductivity as thesalt concentration decreased especially in the top soil layer .When extraction medium was applied.

  • PDF

Effect of Bamboo salt-pro on carries-inducing properties of Streptococcus mutans

  • Shin, Hye-Young;You, Hyeon-Hee;Shin, Tae-Yong;Kim, Hyung-Min;You, Yong-Ouk
    • Advances in Traditional Medicine
    • /
    • 제3권1호
    • /
    • pp.40-45
    • /
    • 2003
  • We studied the effect of Bamboo salt-pro on the growth and acid production of S. mutans. The growth of S.mutans was reduced by the presence of the Bamboo salt-pro (1 mg/ml) and NaCl (1 mg/ml) significantly, and the positive control group (1 % of NaF) also exhibited antibacterial activity significantly. Bamboo salt-pro (1 mg/ml) reduced the rate of acid production by S. mutans. Bamboo salt alone did not demonstrate such a reduction in acid production at the concentration of 1 mg/ml. The inhibitory action of Bamboo salt-pro on acid production was found at a concentration of 1 mg/ml, but bamboo salt alone was not at a concentration of 1 mg/ml. In addition, we investigated the anti-inflammatory effect of Bamboo salt-pro on human mast cell line HMC-1. Bamboo salt-pro (0.1 and 0.01 mg/ml) inhibited significantly the secretion of inflammatory cytokine, tumor necrosis factor-a with $59.47{\pm}0.15%$, $51.98{\pm}0.16%$ respectively. Our results suggest that Bamboo salt-pro importantly contributes to the prevention or treatment of periodontitis and other oral diseases and inflammatory diseases.

해안으로부터 거리별 비래염분량의 분포에 대한 고찰 (A study on the distribution of airborne sea salt to the distance from seashore)

  • 이종석;최원성;문한영
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
    • /
    • pp.842-845
    • /
    • 2004
  • When the concrete structures are in contact with seawater, concentration of chloride for estimating chloride diffusion coefficient can be defined as the chloride concentration of sea water. However, in case the concrete structures, constructed in the seashore, aren't directly in contact with seawater, it is difficult to establish the interface concentration of chloride. In addition, marine concrete structures are greatly affected by salt attack such as rebar corrosion, among the cause of salt attack, airborne sea salt is primary factor. Therefore, in this study, salt attack environment by airborne sea salt was investigated in terms of the distance from seashore at 33 spots, 6 areas in East, West, South coast for 1 year. Results indicated that airborne sea salt is decreased by $y=a{\cdot}x^{-b}$ equation to the distance from seashore.

  • PDF

실온 저장 새우젓의 이화학적 미생물학적 특성에 미치는 염농도의 영향 (Effect of Salt Concentration on the Quality of SaewooJeot(Salted Shrimp) Fermented at Room Temperature)

  • 오상희;허옥순;신현수;이주운;김동호;변명우;김미리
    • 동아시아식생활학회지
    • /
    • 제15권4호
    • /
    • pp.444-449
    • /
    • 2005
  • Effect of salt concentration on the quality of Saewoojeot (salted shrimp) fermented at room temperature was evaluated Salted shrimp with three different salt concentration (9, 18 and $27\%$) were prepared with fresh shrimp, and fermented at $20^{\circ}C$ temperatures for 180 days. Amino nitrogen (AN), volatile basic nitrogen (VBN) and trimethylamine (TMA) contents increased with longer fermentation time and lower salt concentration. AN, VBN and TMA contents in salted and fermented shrimp with $9\%$ salt increased rapidly during fermentation period, while that with 18 and $27\%$ salt maintained its initial level through 180 days of fermentation. When salted and fermented shrimps were fermented at $20^{\circ}C$, all the indexes of fermentation process maintained stable with $27\%$ salt level. Pathogenic bacteria such as pathogenic Echerichia coli, Salmonella spp., were not detected in the manufactured salted and fermented shrimps. However, coliform and yeast disappeared within 180 days and 100 days of storage for 18 and $27\%$ salt, respectively. Gram positive cocci survived until 180 days of storage against $18\%$($10^3-10^6$ CFU/g) and $27\%$($0-10^6$ CFU/g) salt.

  • PDF

수산물 가공폐수내 염분농도가 고율 혐기성 소화에 미치는 영향 (Effect of the Salt Concentration in Seafood Wastewater on the High-Rate Anaerobic Digestion)

  • 최용범;한동준;이해승;권재혁
    • 대한환경공학회지
    • /
    • 제35권10호
    • /
    • pp.730-736
    • /
    • 2013
  • 본 논문은 수산물가공 폐수내 염분농도가 고율 혐기성 소화공정에 미치는 영향을 파악하고자 수행되었다. HRT 6 hr 이상에서 TCODcr의 제거효율은 81.1~90.7%로 조사되어, 수산물 가공폐수 처리를 위한 최적 HRT는 6 hr 이상으로 조사되었다. 유기물 부하 7.83~17.37 $kgTCODcr/m^3$/day$에서 TCODcr 제거당 메탄 발생량은 0.23~0.38 $m^3CH_4/kgCODrem.$으로 STP 상태의 이론적 메탄가스 발생량 $0.35m^3CH_4/kgTCODrem$.과 유사하게 조사되었다. 운전기간 동안 biogas내 메탄 함량은 70.1~76.8%로 유입부하 변동에 거의 영향을 받지 않았다. 염분농도에 따른 혐기성 소화효율 검토결과, $4,000mgCl^-/L$ 이하에서 TCODcr의 제거효율은 83.4~89.2%로, $5,000mgCl^-/L$에서는 70% 중반의 제거효율을 나타내, 안정적인 처리효율을 위해서는 $4,000mgCl^-/L$ 이하로 유지하여야 한다. biogas내 메탄함량은 $3,000mgCl^-/L$ 이하에서는 64.7~73.3%로 조사되었으나 $4,000mgCl^-/L$ 이상에서는 50.1~56.9%로 염분농도가 증가할수록 감소하였다.