• Applied Biological Chemistry
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• 제45권3호
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• pp.145-151
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• 2002

수도용 제초제로 널리 사용되는 molinate는 물에 대한 용해도가 매우 크기 때문에 상수원수로 유입될 가능성이 있다. 상수원수에 molinate가 유입되었을 경우 상수처리과정 중에서의 제거효율을 알아보기 위하여 본 연구를 수행하였다. 상수처리과정중 응집제로 poly aluminium chloride(PAC)를 사용하였을 경우에는 molinate는 거의 제거되지 않는 것으로 나타났다. 소독제로 NaCIO를 사용한 염소처리과정에서는 4시간까지 염소투입량을 증가시켜 줌에 따라서 $20.0%{\sim}39.8%$의 제거율을 나타내었다. 고도정수처리과정에 해당되는 오존접촉과정에서는 접촉시간을 1시간까지 두었을 때 $28.9%{\sim}$58.2%의 제거율을 나타내었다. 활성탄처리과정의 경우는 입상활성탄의 첨가량 달리 하였을 때 30분의 접촉시간이 지난 후 90%이상의 제거효율을 나타내었으며, 1시간 후에는 완전히 제거되는 것으로 나타났다. 활성탄의 형태에 따른 제거효율은 비표면적이 더 널은 분말활성탄이 입상활성탄을 사용하였을 때보다 다 높게 나타났다. 고도정수처리과정인 오존접촉과 활성탄처리과정을 연속적으로 행한 결과 비교적 짬은 처리 시간에도 불구하고 $93.9%{\sim}100% 제거되었다. 상수처리의 각 과정별 molinatr치 제거율을 계산하여 모식화한 결과 전체 system에서의 효율은 99.5%로 나타나 수중 molinate의 제거에 상당히 효율적인 것으로 나타났다.

• 자원리싸이클링
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• 제16권5호
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• pp.3-7
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• 2007

알루미늄 지금 및 스크랩 용해시 발생되는 알루미늄 폐드로스를 사용하여 황산알루미늄(Alum)과 폴리염화알루미늄(pooly Aluminium Chloride: PAC)을 제조하였다. 알루미늄 폐드로스를 황산과 반응시켜 폐드로스 중에 잔류하는 금속알루미늄을 용액 중으로 침출시켜 황산알루미늄 용액으로 제조하였으며, 알루미늄 폐드로스를 염산과 반응시켜 PAC 용액으로 제조하여 수처리응집제로 재활용하고자 하였다. 이와 같이 알루미늄 폐드로스를 재활용함으로써 수산화알루미늄을 원료로 사용하여 황산알루미늄과 PAC를 제조하는 종래의 방법에 비해 제품의 원료비를 줄일 수 있고, 매립 등으로 폐기시켜야 할 폐드로스의 양을 줄이는 효과가 있었다.

• Computers and Concrete
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• 제33권6호
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• pp.631-642
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• 2024

The present study concerns the corrosion mitigation of electrochemical chloride extraction (ECE) in concrete structure. Concrete specimen was fabricated with 5.0% chloride in cast, while the other specimen was exposed to 4.0M NaCl solution for 1 year to accelerate corrosion of steel. Then, the ECE was applied to the concrete specimen with 1000 mA/m² of the current density for 2, 4 and 8 weeks, respectively. During the ECE, the corrosion current density and corrosion potential were regularly monitored. As a result, the ECE was very effective in mitigating the degree of corrosion on the steel surface. The corrosion current density was significantly reduced from thousands to decades mA/m², while the corrosion potential was mostly shifted to positive direction. Assuming that the corrosion starts at 1.0 mA/m² of the corrosion current density or/and -275 mV vs SCE of the corrosion potential, the ECE could not fully achieve the repassivation of the steel, although its degree was lowered more or less depending on the duration of the treatment and type of chloride contamination. A visual examination confirmed that an increase in the duration of the treatment could lower the rust formation, but never fully removed all rust stains.

• Journal of Microbiology and Biotechnology
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• 제28권4호
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• pp.503-509
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• 2018

Endive is widely consumed in a fresh-cut form owing to its rich nutritional content. However, fresh-cut vegetables are susceptible to contamination by pathogenic bacteria. This study investigated the antibacterial activities of the combined treatment of cinnamon leaf oil emulsion containing cetylpyridinium chloride or benzalkonium chloride (CLC and CLB, respectively) as a cationic surfactant and ultrasound (US) against Listeria monocytogenes and Escherichia coli O157:H7 on endive. The combined treatment of CLC or CLB with US reduced the population of L. monocytogenes by 1.58 and 1.47 log colony forming units (CFU)/g, respectively, and that of E. coli O157:H7 by 1.60 and 1.46 log CFU/g, respectively, as compared with water washing treatment. The reduction levels of both pathogens were higher than those observed with 0.2 mg/ml sodium hypochlorite. In addition, the combined treatment showed no effect on the quality of the fresh-cut endive (FCE). In particular, the degree of browning in FCE was less for the treatment group than for the control and water washing treatment groups. Thus, cationic surfactant-based cinnamon leaf oil emulsions combined with US may be an effective washing treatment for the microbial safety of FCE.

• 자원리싸이클링
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• 제15권5호
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• pp.52-56
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• 2006

국내 알루미늄 재생업체에서 알루미늄 용해시 발생되는 알루미늄 폐드로스를 사용하여 수처리응집제로 사용되는 폴리염화알루미늄(PAC: Poly Aluminium Chloride)를 제조하였다. 알루미늄 폐드로스를 염산과 반응시켜 폐드로스 중에 잔류하는 금속알루미늄을 PAC용액으로 제조함으로써 수산화알루미늄과 염산을 원료로 사용하여 PAC를 제조하는 종래의 방법에 비해 제품의 원료비를 줄일 수 있고, 알루미늄 폐드로스를 재활용함으로써 매립 등으로 폐기시켜야 할 폐드로스의 양을 줄이는 효과가 있다.

• Journal of Applied Biological Chemistry
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• 제61권4호
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• pp.383-389
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• 2018

Degradation of the insecticide O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate (chlorpyrifos) in aqueous solution was investigated using iron salts and potassium persulfate during ZVI treatment through a series of batch experiments. The degradation rate of chlorpyrifos increased with increases in the concentrations of iron salts and potassium persulfate in the aqueous system. Ferric chloride was found to be the most effective iron salt for the ZVI-mediated degradation of chlorpyrifos in aqueous solution. Further, the iron salts tested could be arranged in the following order in terms of their effectiveness: $FeCl_3$> $Fe_2(SO_4)_3$> $Fe(NO_3)_3$. The persulfate-ZVI system could significantly degrade chlorpyrifos present in the aqueous medium. This revealed that chlorpyrifos degradation by treatment with $Fe^0$ was promoted on adding ferric chloride and potassium persulfate. The kinetics of the degradation of chlorpyrifos by persulfate-amended $Fe^0$ was higher than that for iron-salt-amended $Fe^0$. This suggests that using a sequential $Fe^0$ reduction-ferric chloride or $Fe^0$ reduction-persulfate process may be an effective strategy to enhance the removal of chlorpyrifos in contaminated water.

• Applied Microscopy
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• 제21권2호
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• pp.76-95
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• 1991

A single injection of cadmium chloride (3.75 mg/kg) was made into the peritoneal cavities of albino rats. The cortices of kidney were obtained from the experimental animals at 3 hr., 6 hr., 12 hr., 24 hr. and 36 hr. after administration of cadmium chloride, respectively. The specimens of each experimental animal were prefixed in 2% glutaraldehyde-4% paraformaldehyde solution for $2{\sim}4$ hours, and these specimens were post-fixed in 1% osmic acid. After fixation, the specimens were dehydrated with alcohol and acetate and embedded in Epon 812. Ultrathin sections, $600{\sim}800{\AA}$ thickness were made and stained with uranyl acetate and lead citrate. And all the preparations were observed with Hitachi-600 transmission electron microscope. The results obtained were as follows: 1. The main changes in ultrastructures of the glomeruli observed at 3 hr. after cadmium chloride administration include loss of filtration slit and fenestrae of capillary endothelium that was resulted from thickings of the basal lamina and fusion of pedicels of the podocytes. At 12 hr. after cadmium chloride administration the Bowman's capsules were mostly filled with abnormally thickened and fused pedicels. After 24 hr. however, the only recognized change was loss of fenestrae of the capillary endothelium. And the ultrastructure of the glomeruli were almost normal in 36 hr. after cadmium chloride treatment. 2. At 3 hr. after treatment with cadmium chloride, in the renal tubular cells the vesicles and vacuoles increased in number at the apical portion, of the tubular epithelial cells, the basal infoldings were reduced and the basal lamina was thickened. After 12 hr., a number of phagosomes appeared at the apical portion and the cisternae of rough endoplasmic reticulum were swollen. At 24 hr. after cadmium chloride administration irregularly shaped mitochondria were observed in the apical area, and mitochondria with swollen cristae were found at the basal portion. And after 36 hr. The ultrastructures of the epithelial cells appeared almost normal except for a moderate increase in the number of vesicles and vacuoles. Consequently it is suggested that in albino rats, cadmium chloride induces acute reversible degenerative changes in the glomeruli as well as in the epithelial cells of the proximal convoluted tubules.

• 대한환경공학회지
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• 제32권3호
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• pp.256-263
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• 2010

본 논문은 염분농도가 호기성 생분해도에 미치는 영향을 파악하고, 그 결과를 수산물 가중 폐수 처리 위한 기초자료로 사용하기 위하여 수행되었다. $Cl^-$농도(1,400~18,000 mg/L)에 따른 유기물 제거효율 검토결과, $Cl^-$ 6,000 mg/L 이하에서 미생물들은 염분에 적응하였으나 $Cl^-$ 12,000 mg/L 이상에서는 반응시간이 길어져도 처리효율이 개선되지 않는 것으로 조사되었다. 생물학적 분해불가능한 용존성 유기물 함유계수 $Y_I$와 미생물 신진대사에 의한 inert 물질 생성계수 Yp는 염분농도가 증가할수록 증가하였으며, $Cl^-$ 농도(0~18,000 mg/L)에 따른 용존성 유기물 비율은 10.8~13.1%로, 미생물 신진대사에 의한 inert 물질 생성비율은 7.0~24.6%로 조사되었다. $NH_3$-N 제거효율은, 원폐수는 HRT 18 hr에서 96.2%의 제거효율을 보였으나, $Cl^-$ 6,000 mg/L, HRT 22 hr에서 96.5%, $Cl^-$ 12,000 mg/L, HRT 30 hr에서 90.2%, $Cl^-$ 18,000 mg/L, HRT 45 hr에서 90.3%의 제거효율을 나타내, 질산화 과정이 유기물 제거 보다 염분농도에 더 민감한 것으로 조사되었으며, 폐수내 $Cl^-$ 6,000 mg/L 이상부터는 $NO_2$-N에서 $NO_3$-N로의 전환율도 낮게 조사되었다.

• BMB Reports
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• 제36권5호
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• pp.468-474
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• 2003

The molecular mechanism of hypoxia-induced apoptosis has not been clearly elucidated. In this study, we investigated the involvement of extracellular signal-regulated protein kinase (ERK 1/2) in hypoxia-induced apoptosis using cobalt chloride in HeLa human cervical cancer cells. The cobalt chloride was used for the induction of hypoxia, and its $IC_{50}$ was $471.4\;{\mu}M$. We demonstrated the DNA fragmentation after incubation with concentrations more than $50\;{\mu}M$ cobalt chloride for 24 h, and also evidenced the morphological changes of the cells undergoing apoptosis with electron microscopy. Next, we examined the signaling pathway of cobalt chloride-induced apoptosis in HeLa cells. ERK1/2 activation occurred 6 and 9 h after treatment with $600\;{\mu}M$ cobalt chloride. Meanwhile, the pretreatment of the MEK 1 inhibitor (PD98059) completely blocked the cobalt chloride-induced ERK 1/2 activation. At the same time, the activated ERK 1/2 translocated into the nucleus and phosphorylated its transcriptional factor, c-Jun. In addition, the pretreatment of PD98059 inhibited the cobalt chloride-induced DNA fragmentation and apoptotic cell death. These results suggest that cobalt chloride is able to induce apoptotic activity in HeLa cells, and its apoptotic mechanism may be associated with signal transduction via ERK 1/2.

• 한국축산식품학회지
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• 제34권2호
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• pp.221-229
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• 2014

Chicken breast meat was injected with calcium chloride alone and in combination with lactic acid (0.01% and 0.002%, respectively). The inhibitory effects of the treatments on microbial growth were determined in the injected chicken breast meat stored at $4^{\circ}C$ under aerobic packaging condition for 0, 3, and 7 d. Calcium chloride combined with 0.002% and 0.01% lactic acid reduced microbial counts by 0.14 and 1.08 Log CFU/g, respectively, however, calcium chloride alone was unable to inhibit microbial growth. Calcium chloride combined with 0.01% lactic acid was the most effective antimicrobial treatment and resulted in the highest initial redness value. Calcium chloride alone and combined with lactic acid suppressed changes in pH and the Hunter color values during storage. However, injection of calcium chloride and lactic acid had adverse effects on lipid oxidation and sensory characteristics. The higher TBARS values were observed in samples treated with calcium chloride and lactic acid when compared to control over the storage period. Addition of calcium chloride and lactic acid resulted in lower sensory scores for parameters tested, except odor and color, compared to control samples. Therefore, the formulation should be improved in order to overcome such defects prior to industrial application.