• 대한기계학회논문집B
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• 제25권1호
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• pp.124-132
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• 2001

This paper reports on the charge distribution measurements of submicron particles for three different charging mechanisms, which are spray electrification, bipolar ionization and corona discharge process, respectively. The number of elementary charges per particle was investigated by classifying and counting of a discrete mobility class. Charge distribution measurements were performed with NaCl particles generated from a collision atomizer for 0.01, 0.1, 1% NaCl solutions. Experimental results show than charge level of atomized NaCl particles is high and decreases with increasing the dissolved ion concentration. The charge level of the atomized NaCl particles can be reduced to that o Boltzmann equilibrium conditions by the bipolar ionization(Po(sup)210 bipolar ionizer). The charge level on NaCl particles passing through the corona discharge reactor is much higher than those of atomized or bipolar ionized NaCl particles. The evaluation of these measurements results in charge distribution of the submicron particles.

• 한국축산식품학회지
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• 제32권3호
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• pp.293-300
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• 2012

This study investigated the effects of a low-voltage ohmic heating process (2.5 and 3.8 V/cm) on the thawing characteristics and NaCl diffusion of pork. The thawing rate of pork was dependent on the applied voltages and brine salinities, and few differences were obtained in pork quality parameters (color, water-holding capacity, and shear force) regarding the different treatments. The NaCl concentration of pork after ohmic thawing was higher than that following brine-immersion thawing, however, the NaCl diffusion did not differ from when fresh meat was immersed in brine. For application of the ohmic process in fresh pork, various ohmic pulses were generated in order to prevent the meat from overheating, and the results indicated that the ohmic process was a better way to enhance NaCl diffusion compared with immersing pork at high temperature. Although the mechanisms involved in NaCl diffusion at low-voltage electric field strength were unclear, the present study demonstrated that the ohmic process has a potential benefit in the application of meat processing.

• Nuclear Engineering and Technology
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• 제43권3호
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• pp.195-204
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• 2011

The effects on pool boiling heat transfer of aqueous solutions of boric acid ($H_3BO_3$) and sodium chloride (NaCl) as working fluids have been studied. Borated and NaCl water were prepared by dissolving 0.5~5% volume concentration of boric acid and NaCl in distilled-deionized water. The pool boiling tests were conducted using $1{\times}1\;cm^2$ flat heaters at 1 atm. The critical heat flux (CHF) dramatically increased compared to boiling pure water. At the end of boiling tests it was observed that particles of boric acid and NaCl had deposited and formed a coating on the heater surface. The CHF enhancement and surface modification during boiling tests were very similar to those obtained from boiling with nanofluids. Additional experiments were carried out to investigate the reliability of the additives deposition in pure water. The boric acid and NaCl coatings disappeared after repeated boiling tests on the same surface due to the soluble nature of the coatings, thus CHF enhancement no longer existed. These results demonstrate that not only insoluble nanoparticles but also soluble salts can be deposited during boiling process and the deposited layer is solely responsible for significant CHF enhancement.

• KSBB Journal
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• 제13권2호
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• pp.168-173
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• 1998

Gamma irradiated and non-irradiated Agrimonia pilosa Ledebour were extracted by 70% ethanol. The combined effects of the Agrimonia pilosa Ledebour extract and NaCl on survival of Escherichia coli O157:H7 in tryptic soy broth were investigated. E. coli O157:H7 decreased ca 1 log cycle by the addition of 2% sample extract, and the anthbacterial activity was increased as the concentration of sample extract was increased. The irradiation effect of the sample on antibacterial activity was not observed. On the treatment of NaCl alone, E. coli O157:H7 was inactivated (ca 3~4 log cycle reduction within 48 hr) in more than 7% NaCl. The higher inactivation(ca 5 log cycle reduction within 48 hr) occurred in the presence of 2% sample extract and 5% NaCl than in the addition of each alone. The extracted antibacterial substance was stable in the pH range of 4.0 to 7.0, heat treatment at 121$^\circ C$ for 15 min, and freezing at -18$^\circ C$ and thawing at 37$^\circ C$. There fore, the sample extract, would substantially increase the food-safety in terms of E. coli O157:H7.

• 멤브레인
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• 제5권2호
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• pp.81-88
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• 1995

NaCl과 sucrose 용액을 역삼투용 워난틀형 모듈에 공겁하여 투과실험하였으며 Kimura-Sourirajan[8]이 제안한 방법으로 분리성능을 분석하였다. 사용한 분리막의 순수투과계수는 압력에 무관하게 $2.17 \times 10^{-6}$(gmol/$cm^2$-sec-bar)로 일정하게 유지되었다. Sucrose 용액의 농도분극화 현상은 NaCl 용액보다 심각하였으며 40bar 이상에서는 압력이 증가함에 따라서 오히려 투과선속이 감소하였다. 용질 배제율은 NaCl 수용액의 경우 압력이 증가함에 따라서 감소하였으나 sucrose 수용액의 경우는 압력에 따라서 배제율도 증가하였다.

• 한국환경과학회지
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• 제12권10호
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• pp.1131-1136
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• 2003

To examine whether salt stress would alter or not contractility of isolated rat aorta, under anesthesia with sodium pentobarbital(50 mg kg-1 i.p.), male Sprague Dawley rats(300-330 g) were subjected to 0, 50, and 150 mM of sodium chloride at 37$^{\circ}C$ for 60 min. where as the sham group was left at modified Krebs-bicarbonate solution. To measure contractile response of vascular ring preparation isolated from rat was determined in organ bath and was recorded on physiograph connected to isometric transducer. And the strip was checked for expression of heat shock protein(Hsp) by Western blotting. One, three and eight hours later, we measured vascular contractility of isolated rat aorta treated with KCI, phenylephrine from organ bath study. The dose-vascular responses of potassium chloride and phenylephrine showed a little augmentation by NaCl concentration in the strips exposed to NaCl for 8 hours. And the response of relaxation induced by nitroprusside and acetylcholine was not influenced by NaCl stress in isolated aorta ring for 8 hours, respectively. Expression pattern of Hsp 70 of vascular muscle in isolated rat aorta showed a little increase in 150 mM NaCl group at 8 hours after NaCl treatment but not at 3 hours, and Hsp 60 expression of rat aorta was markedly increased in 50 mM NaCl group at 8 hours after NaCl treatment. Taken together, NaCl induced dose-and time dependent accumulation of the Hsp but not affected contraction of rat aorta. These data suggest that short term high salt stress was not sufficient to induce hypertension of rat aorta.

• Journal of Microbiology and Biotechnology
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• 제29권2호
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• pp.191-199
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• 2019

We inoculated different combinations of three starter candidates, Bacillus licheniformis, Staphylococcus succinus, and Tetragenococcus halophilus, into sterilized soybeans to predict their contributions to volatile compound production through soybean fermentation. Simultaneously, we added NaCl to soybean cultures to evaluate its effect on the volatile compounds profile. Cells in soybean cultures (1.5% NaCl) nearly reached their maximum growth in a day of incubation, while cell growth was delayed by increasing NaCl concentrations in soybean cultures. The dominance of B. licheniformis and S. succinus in the mixed cultures of three starter candidates switched to T. halophilus as the NaCl concentration increased from 1.5% to 14% (w/w). Seventeen volatile compounds were detected from the control and starter candidate-inoculated soybean cultures with and without the addition of NaCl. Principal component analysis of these volatile compounds concluded that B. licheniformis and S. succinus made major contributions to producing a specific volatile compound profile from soybean cultures where both species exhibited good growth. 3-Hydroxybutan-2-one, butane-2,3-diol, and 2,3,5,6-tetramethylpyrazine are specific odor notes for B. licheniformis, and 3-methylbutyl acetate and 2-phenylethanol are specific for S. succinus. Octan-3-one and 3-methylbutan-1-ol were shown to be decisive volatile compounds for determining the involvement of S. succinus in the soybean culture containing 7% NaCl. 3-Methylbutyl acetate and 3-methylbutan-1-ol were also produced by T. halophilus during soybean fermentation at an appropriate level of NaCl. Although S. succinus and T. halophilus exhibited growth on the soybean cultures containing 14% NaCl, species-specific volatile compounds determining the directionality of the volatile compounds profile were not produced.

• 대한환경공학회지
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• 제39권4호
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• pp.186-193
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• 2017

마이크로웨이브(MW)는 유전가열에 의한 열적, 비열적 그리고 이온성 전도 효과를 가지며 높은 에너지 효율을 보이므로 유기성 폐기물의 가용화에 대해 효과적인 방법이다. 본 연구는 고형물 함량이 높은 우분을 대상으로 MW를 이용하여 가용화 최적 조건을 도출하고 이를 토대로 MW의 유전가열 특성을 향상시키기 위해 화학적 촉매물질인 $H_2SO_4$과 NaCl을 첨가하여 우분의 가용화율과 가용화 방법에 따른 biochemical methane potential (BMP)을 평가하였다. 우분 고형물 농도 12%와 MW 출력 800 W 및 설정온도 $40^{\circ}C$ 조건에서 70.5 mg $SCOD_{increased}/kJ$로 에너지 대비 최대 가용화율을 보여주었으며, 이때의 SCOD 농도는 원시료 대비 53.2% 증가하였다. 가용화 최적 조건에서 화학적 촉매로 $H_2SO_4$를 주입하였을 경우 MW 단독 처리 대비 SCOD 농도는 36% 증가하였으며, NaCl을 주입하였을 경우 22.7% 증가하였다. BMP test에서도 우분 원시료 대비 MW를 이용한 가용화는 메탄 생성량이 6.7%, $H_2SO_4$를 주입한 MW 가용화는 13.3%, NaCl을 주입한 MW 가용화는 11.3% 증가하였다. 따라서 마이크로웨이브는 우분의 가용화 전처리에 효율적인 수단이며, 마이크로웨이브의 가용화 효율을 높이기 위해서는 화학적 촉매를 이용할 필요가 있다.

• 한국해양공학회지
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• 제6권1호
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• pp.140-147
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• 1992

Corrsion fatigue test was performed under rotated bending in 3.5% NaCl aqueous solution having a temperature from 278.deg.K in order to investigate the effects of aqueous solution remperature on the corrosion fatigue fracture of raw material steel(SS41) and dual phase steel that was produced from SS41 by a series of heat treatment. Corrosion fatigue life decreases remarkably with increase in solution temperature or with decrease in stress level. The corrosion fatigue life and the crack propagation rate at 303.deg.K show the similar behaviors with those at 318.deg.K, which is assumed to be caused by concentration polarization phenamena. The number and the lengths of microcracks increase with increase in solution temperature, so they lead to the decrease in corrosion fatigue life.

• 한국식품영양학회지
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• 제9권3호
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• pp.319-324
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• 1996

The functional properties of protein recovered from red crab (Chitinonecetes opiiie) processing in water (RCP) were examined and compared with those of soybean protein isolate at pH 2~10 in water and NaCl solu5ion. The solubilities of RCP and SPI were miniumu at pH 4, the isoelectric point and increased significantly at lower or higher than pH 4. Solubilities in NaCl solution for both proteins decreased with incr NaCl concentration increase at all pH ranges. Emulsion capacity for both proteins was also minimum at pH 4 and increased as protein concentration increased from 2 to 6%. Emulsion capacity of RCP was higher than these of SPI at pH 6∼10 and all protein concentrations. Emulsion stability showed a similar trend to that of emulsion capacity. RCP had higher oft absorption capacity and lower water absorption capacity than SPI.