• The Journal of Engineering Geology
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• v.5 no.1
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• pp.75-93
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• 1995

This study investigates the adsorption capacity of the gibbsite and the clay on the development of admixed liner. The gibbsite is produced as a by-product in the pretreatment process for cleaning and coloring of Alurninurn sash. From the study, following conclusions were obtained: 1) The adsorption of metals such as Cu(II), Cd(II), and Ni(II) and phenol on gibbsite and l:entonite was equilibrated rather quickly(12 ~48 hrs ). 2) The rate and extent of adsorption is a function of surface area the adsorbent having. 3) The Larigmuir isotherm is found to be more suitable than Freundlich isotherm for the adsorption analysis of heavy metals on gibbsite and bentonite. 4) In case of phenol, Freundlich isotherm, whose N value is close to 1, i.e., close to linear isotherm, is more fit to describe the adsorption on gibbsite and bentonite. 5) The amount of metals and phenol adsorbed is found to be in the following order : Adsorbent : $2{\mu}m-Al(OH)_3$ > Mixed Solid > $12{\mu}m-Al(OH)_3$ > Na-Bentonite > $30{\mu}m-Al(OH)_3$

• The Korean Journal of Mycology
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• v.19 no.3
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• pp.220-225
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• 1991

Activities of the $F_1-ATPase$ purified from Lentinus edodes were stimulated by $Fe^{3+},\;Fe^{2+},\;Cd^{2+},\;Mg^{2+},\;K^{+}\;and\;Co^{2+}$ but were inhibited by $Zn^{2+},\;Ca^{2+},\;Cu^{2+}\;and\;Ni{2+}$ ion. The enzyme activities were increased 130, 65, 65, 68, 105% and 23% by the 5mM $Fe^{3+}$, 10 mM$Fe^{2+}$, 1mM $Cd^{2+}$, 5mM $Mg^{2+}$, 5mM $K^{+}$ and 5mM$Co^{2+}$ ion addition, respectively, as compared with those not added. The enzyme activities were decreased 18, 19, 27 and 30% by 10 mM $Zn^{2+}$, 10mM $Ca^{2+}$, 0.5 mM $Cu^{2+}$ and 10 mM $Ni^{2+}$ ion, respectively. Anion effects of 10 mM ${Co_3}^{2-}$, 20 mM,$CN^{-}$ 20 mM$CH_3COO^{-}$ and 20 mM ${NO_3}^{-}$ ion were inhibited to the enzyme activities of 98, 95, 70 and 50%, respectively. As increasing of ${SO_4}^{2-}$ ion concentration, the enzyme activity was stimulated and 20 mM ${SO_4}^{2-}$ ion was shown increased of 21%.

• Analytical Science and Technology
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• v.9 no.4
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• pp.336-344
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• 1996

The extraction of trace cobalt, copper, nickel, cadmium, lead and zinc in urine samples of organic and alkali metal matrix into chloroform by the complex with a dithizone was studied for graphite furnace AAS determination. Various experimental conditions such as the pretreatment of urine, the pH of sample solution, and dithizone concentration in a solvent were optimized for the effective extraction, and some essential conditions were also studied for the back-extraction and digestion as well. All organic materials in 100 mL urine were destructed by the digestion with conc. $HNO_3$ 30 mL and 30% $H_2O_2$ 50 mL. Here, $H_2O_2$ was added dropwise with each 5.0 mL, serially. Analytes were extracted into 15.0 mL chloroform of 0.1% dithizone from the digested urine at pH 8.0 by shaking for 90 minutes. The pH was adjusted with a commercial buffer solution. Among analytes, cadmium, lead and zinc were back-extracted to 10.00 mL of 0.2 M $HNO_3$ from the solvent for the determination, and after the organic solvent was evaporated, others were dissolved with $HNO_3-H_2O_2$ and diluted to 10.00 mL with a deionized water. Synthetic digested urines were used to obtain optimum conditions and to plot calibration-eurves. Average recoveries of 77 to 109% for each element were obtained in sample solutions in which given amounts of analytes were added, and detection limits were Cd 0.09, Pb 0.59, Zn 0.18, Co 0.24, Cu 1.3 and Ni 1.7 ng/mL, respectively. It was concluded that this method could be applied for the determination of heavy elements in urine samples without any interferences of organic materials and major alkaline elements.

• Macromolecular Research
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• v.17 no.4
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• pp.276-279
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• 2009

• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.60-65
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• 2001

Thermal spray coating is formed by a process in which melted particles flying with high speed towards substrate, then crash and spread on the substrate surface cooled and solidified in a very short time, Stacking of the particles makes coating. In this study, the exfoliation of $Al_2$O$_3$ and Ni-4.5wt.%Al thermally sprayed coating which were deposited by an atmospheric plasma spray apparatus are investigated using an AE method. A tensile test is conducted on notch specimens in a stress range below the elastic limit of substrate. The wave forms of AE generated from the three coating specimens can be classified by FFT analysis into two types which low frequency(type I waveform is considered to corresponds exfoliation of coating layers and type II waveform corresponds the plastic deformation of notch tip or the resultant fracture of coating. The fracture of the coating layers can estimate by AE event and amplitude, because AE features increase when the deformation generates.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1473-1476
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• 2008

Doping the nanoparticles of Pd, p-$BaTiO_3$, $SiO_2$ and MgO into LCs alters their physical properties such as $K_{ii}$, $\Delta\varepsilon$, ${\Delta}n$, $\gamma_1$ and $T_{NI}$. Except for $K_{33}$, all these parameters decreases and thus bring the reduction of operating voltage and/or response times.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.221-221
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• 1999

산소 플라즈마의 음이온 발생 특성을 정전 탐침을 이용하여 관찰하였다. 탐침에 흐르는 음 전류는 전자 전류와 음이온 전류의 합으로 구성되며 음이온 속도는 전자 속도에 비해 작아 음이온의 발생 량이 증가함에 따라 음이온 전류의 크기는 감소하게 된다. 따라서 탐침에 흐르는 양 전류와 음전류의 비 Ii*/(Ie*+I-*)는 음이온의 발생량에 따라 변화하게 된다. 또한 플라즈마 전위와 부유 전위간의 전위차와 음 이온밀도와의 관계는 다음과 같은 관계식 e(Vp-Vf)/Te={3.35 + 0.5 ln$\mu$ - ln(ni/ne)]을 갖으며 이로부터 음이온의 밀도를 측정할 수 있다. 이들 두 가지 방법을 이용하여 정전 탐침에서 얻어지는 탐침 자료로부터 직접 플라즈마에서 음이온 발생에 관한 정성적인 특성 변화를 관찰할 수 있었다. 본 실험에서는 운전 압력(0.1-600mTorr)과 입력 전력(50-500W)에 따른 DC, ICP, CCP에서 발생하는 산소 음이온 플라즈마의 발생 특성을 분석하였다. 운전 압력이 증가함에 따라 음이온의 비율이 증가하다가 감소함이 관찰되었으며 400mTorr에서 최대 30%의 음이온 발생 비율을 갖음을 알 수 있었으며 더 큰 압력 하에서는 발생률이 점차 감소함을 관찰되었다. 또한 음이온의 발생 율은 입력 전력보다 운전 압력에 민감하게 변화하였다.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.70-74
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• 1997

Data on 2,571 lactation records of Nili-Ravi buffaloes from four institutional herds and four field recording centers were analyzed under an animal model to see the effect of season definition on the error variance of the fitted model. Herd-year-season(HYS) was the main fixed effect along with permanent environment, breeding value and residuals as the random effects. All known relationships among the animals were considered. The error variance differed for various HYS combinations. It was minimum when then months were not grouped into seasons. The four or Five season scenarios were better than the two season scenarios. The average number of lactations represented in a HYS combination varied widely from 6 to 28. Very few subclasses for a given HYS combination warrants the use of fewer seasons for animal model evaluation of buffaloes.

• Analytical Science and Technology
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• v.13 no.6
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• pp.810-814
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• 2000

The open-chain hexadentate $N_4$, $O_2$ ligands 1, 15-bis(2-hydroxybenzyl)-2, 6, 10, 14-tetraazapentadecane (BSATPD. 4HCl) has been synthesized as its tetrahydro-chloride salt and characterized by EA, IR, NMR, and Mass spectrum. Its protonation constants ($logK_n{^H}$) and stability constants ($logK_{ML}$) for $Cu^{2+}$, $Ni^{2+}$, $Co^{2+}$ and $Zn^{2+}$ ions were determined in aqueous solution by potentiometry and compared with those of analogous $N_4$, $O_2$ ligands contain ethtylenic spacers or propylenic spacers, which make six-membered chelate rings between the aliphatic nitrogen atoms.

• Korean Journal of Plant Resources
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• v.3 no.2
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• pp.115-121
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• 1990

In view of the results to have measured metallic elements which is included in 40 sorts of herb medicines and surveyed their distribution, ninekinds of metals including Co, Ce, Ga, 71, Cd, As, Sbr Bu. Pb, are never orlittle included in almost herb medicines. Other twenty four sorts of ele-ments (Mo, Sc, Be, V, Ni, Su, Se, Ba, Cr, Su, Ti, B, Li, Mg, Ca, Sr, Mnl Fe,Cu, Zn. p, Al, Na, K) are metals that are included in large quentities incomparison with others. Selagirellae Radix contains is kinds of metallicelements more then other herb medicines does. The content of elements ofinorganic metal differs greatly according to the part of herb medicines .