• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1999년도 제51차 추계 학술대회 연제집
• /
• pp.279-280
• /
• 1999

• Bulletin of the Korean Chemical Society
• /
• 제26권7호
• /
• pp.1109-1111
• /
• 2005

• 한국표면공학회지
• /
• 제19권1호
• /
• pp.13-19
• /
• 1986

Manganese in the Anode slime and the paste-positive material of waste-dry cell was recovered by leaching with the hydrochloric acid solution. The impurities (Zn, Fe, Pb), co-leached with manganese were removed from the leached solution prior to electrolysis by hydrometallurgical techniques such as the neutralization with ammonium hydroxide and cementation on manganese powder. The electrodeposition of manganese from the purified chloride solution with sodium selenate was performed. Cathode current efficiency was found to be affected significantly by the concentration of sodium selenate and ammonium chloride salt, bath temperate, current density and PH. The current efficiency of about 88.7% was obtained by electrolysis manganese chloride solution with sodium selenate (0.1/g) at 10$^{\circ}C$.

• Restorative Dentistry and Endodontics
• /
• 제15권1호
• /
• pp.1-15
• /
• 1990

The aim of this study was to investigate the effect of dental therapeutic agent on conduction velocity and threshold current of intradental A- and C-fibers in the cat. Inferior alveolar nerve of cat anesthetized with sodium pentobarbital was exposed and dissected until response of functional single pulp nerve until could be evoked by monopolar electrical stimulation of the crown of the lower left canine teeth. 10ms rectangular pulse was used to determine the threshold current and 1ms rectangular pulse was used to determine conduction velocity. After application of calcium chloride (1, 2, 6M), calcium hydroxide mixed with saline, potassium chloride (0.2, 0.8, 1.6M), eugenol, zinc oxide eugenol to the cavity on the labial surface, conduction velocity and threshold current of single pulp nerve unit were compared with the control. In 10 cats, 24 $A{\delta}$- and 11 C- pulp nerve units were recorded. The mean conduction velocities of $A{\delta}$- and C-fibers were 7.5m/sec (SD=5.8) and 1.2m/sec (SD=0.4), respectively. The mean threshold current was $12.3{\mu}A$ (SD=5.3) for $A{\delta}$-fibers and $24.9{\mu}A$ (SD=8.1) for C-fibers. 1, 2, 6M calcium chloride caused decrease of conduction velocity and remarkable increase of threshold current in $A{\delta}$- and C-fibers. The effect of calcium hydroxide mixed with saline was similar but smaller than calcium chloride solution. 0.2M potassium chloride had insignificant effect. In 0.8M potassium chloride, the threshold current was increased although conduction velocity was not affected. In 1.6M potassium chloride, the threshold current was increased and the conduction velocity was slowed down. Spontaneous activity was recorded frequently for first 5 min but gradually reduced both in $A{\delta}$- and C-fibers. Eugenol had irreversible effect on pulp nerve in that initially there were not certain changes in the conduction velocity and threshold current of $A{\delta}$- and C-fibers, but the responses to electrical stimulation were abruptly disappeared after sustained application and were not recovered. Contrary to eugenol, zinc oxide eugenol did not caused significant increase of the threhold current and caused time dependent decrease of the conduction velocity, and did not show any irreversible change.

• 한국콘텐츠학회논문지
• /
• 제14권11호
• /
• pp.964-971
• /
• 2014

감열지는 열과 극성용매에 민감하여 검게 흑화하기 때문에 일반 종이에 사용하는 지문 현출 시약을 적용할 수 없다. 따라서 본 연구에서는 감열지에 적용할 수 있는 1,2-Indanedione 용액의 제조비율을 제시하고 염화아연의 효과성에 대해 검증하였다. 0.06% 농도의 1,2-Indanedione 용액에서 극성용매의 비율이 3%이하인 경우, 감열지에 손상을 주지 않으면서 좋은 지문 현출 결과를 얻을 수 있었다. 일반 종이용 1,2-Indanedione 용액에서 염화아연용액은 형광과 지속성을 증강시키는 데 사용되지만, 감열지에서는 염화아연용액을 넣지 않은 용액에서 더 좋은 결과를 얻을 수 있었다.

• 자원리싸이클링
• /
• 제7권1호
• /
• pp.7-13
• /
• 1998

The electric arc furnace (EAF) dust used in this experiment showed the formation of an irregular agglomerate of small spherical particles and consisted of 27.5% Fe, 18% Zn, 4.83% Pb and 10.2% CaO, and it also contained 3.26% Cl and 0.15% F. IR spectra peaks of Pb(OH)Cl were observed at 1630 and 1377 ${cm}^{-1}$ regions and the intensity decreased using an acid treatment (1N ${H}_{2}{SO}_{4}$) and thermal treatment at above 600℃, but it was not affected by washing process. Those of ${Zn}_{5}{(OH)}_{8}{Cl}_{2}$ treated by oxidation showed broad absorption peak at 3600∼3200 ${cm}^{-1}$, main peaks at 1136 and 1040 ${cm}^{-1}$ and a splitting peak at 991 and 921 ${cm}^{-1}$ which were believed to be due to ZnO by oxidation at about 700∼. The IR spectra of the dust residues by a washing process show the same peaks at 3449, 1635, 1439, 875, 571 and 455 ${cm}^{-1}$ regions, but the peaks at 2942, 2862, 1136 and 1040 ${cm}^{-1}$ decreased and disappeared using an acid treatment and washing process, which is believed to be due to the dissolution of zinc hydroxyl chloride.

• Journal of Electrochemical Science and Technology
• /
• 제11권3호
• /
• pp.257-272
• /
• 2020

This study covers the stages of testing whether the azo dye with chemical name (E)-5-[(4-(benzyl(methyl)amino)phenyl)diazenyl]-1,4-dimethyl-1H-1,2,4-triazol-4-ium zinc (II) chloride (DMT), known as Maxilon Red GRL in the dye industry, can be used as an anticorrosive feasible inhibitory agent, especially in industrial areas other than carpet, yarn and fibre dyeing. These test stages consist of the electrochemical measurement techniques such as potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) for diverse concentrations and durations. The adsorption of the viewed DMT molecule on the mild steel surface obeyed the Langmuir isotherm. The zero charge potential (PZC) of mild steel was also found to assess the inhibition mechanism in containing DMT solution. The inhibition performance of DMT on the mild steel in a 1.0 M HCl solution was also investigated using methods such as metal microscope, atomic force microscope (AFM) and field emission scanning electron microscope (FE-SEM).

• 한국환경과학회지
• /
• 제1권1호
• /
• pp.1.1-11
• /
• 1992

To find heavy metal-specific effects on the photosynthetic apparatus of higher plants, we investigated effects of $CuCl_2$, HgCl_2$ and $ZnCl_2$ on electron transport activity and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings. Effects on some related processes such as germination, growth and photosynthetic pigments of the test plants were also studied. Germination and growth rate were inhibited in a concentration-dependent manner by these metals. Mercury was shown to be the most potent inhibitor of germination, growth and biosynthesis of photosynthetic pigments of barley plants. In the inhibition of electron transport activity, quantum yield of PS II, and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings, mercury chloride showed more pronounced effects than other two metals. Contrary to the effects of other two metals, mercury chloride increased variable fluorescence significantly and abolished qE in the fluorescence induction kinetics from broken chloroplasts of barley seedlings. This increase in variable fluorescence is due to the inhibition of the electron transport chain after PS ll and the following dark reactions. The inhibition of qE could be attributed to the interruption of pH formation and do-epoxidation of violaxathin to zeaxanthin in thylakoids by mercury. This unique effect of mercury on chlorophyll fluorescence induction pattern could be used as a good indicator for testing the presence and/or the concentration of mercury in the samples contaminated with heavy metals.

• 대한환경공학회지
• /
• 제22권1호
• /
• pp.133-139
• /
• 2000

리그닌의 열분해반응 후 발생하는 잔류고형물을 활용해보고자 $ZnCl_2$로 활성화하여 활성탄을 제조하였다. 공정변수로 설정한 활성화 온도, 활성화 시간 및 활성화제의 첨가량 등이 활성탄의 세공구조와 비표면적에 미치는 영향을 조사하여 최적 활성화 조건을 구하였다. 리그닌의 열분해 잔류고형물에 활성화제인 염화아연을 300wt% 첨가한 것을 질소분위기에서 $1000^{\circ}C$로 1시간 동안 활성화시켰을 때 비교적 높은 비표면적과 흡착능을 가지면서 세공구조가 잘 발달된 활성탄을 제조할 수 있었다.

• 한국결정성장학회지
• /
• 제18권1호
• /
• pp.50-55
• /
• 2008

졸-겔 공정을 이용하여 유리기판 위에 Al-doped ZnO(AZO) 박막을 제조하였고, AZO 박막의 특성에 대하여 Al 전구체 종류 및 post-annealing 온도가 미치는 영향에 대하여 고찰하였다. AZO 박막 제조용 졸은 zinc acetate, EtOH, MEA 등을 사용하여 제조하였고, Al doping 을 위한 전구체로는 aluminum nitrate 와 aluminum chloride 를 사용하였다. Sol 내의 Zn 농도는 0.5 mol/l 로 하였고, Al doping 양은 Zn 대비 1 at%로 고정하였다. 유리기판 위에 졸을 spin-coating 한 후 $550^{\circ}C$에서 2 시간 동안 열처리한 후, $N_2$와 $H_2$의 비가 9 : 1인 환원 분위기 내에서 $300^{\circ}C,\;400^{\circ}C,\;500^{\circ}C$인 온도에서 2시간 동안 post-annealing을 진행하였다. 제조된 AZO 박막의 구조적, 전기적, 광학적 특성은 XRD, FE-SEM, AFM, Hall effect measurement system 및 UV-Visible spectroscopy를 이용하여 분석하였다. Al 전구체로서 aluminum nitrate 를 사용한 경우가 aluminum chloride 를 사용하여 제조한 AZO 박막보다 우수한 광학적, 전기적 특성을 나타내었으며, post-annealing 온도가 증가함에 따라 비저항과 투과율은 감소하였다. $500^{\circ}C$에서 post-annealing한 AZO 박막의 전기비저항 값은 $2{\times}10^{-3}{\Omega}{\cdot}cm$이었고, 투과율은 $300^{\circ}C$에서 91%로 가장 높게 나타났다.