• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.549-552
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• 2004

A sensitive, selective and rapid method has been developed for the determination of mercury based on the rapid reaction of mercury(II) with p-sulfobenzylidenethiorhodanine (SBDTR) and the solid phase extraction of the colored chelate with $C_{18}$ disks. In the presence of pH 3.5 sodium acetate-acetic acid buffer solution and Emulsifier-OP medium, SBDTR reacts with mercury(II) to form a red chelate of a molar ratio 1 : 2 (mercury to SBDTR). This chelate was prconcentrated by solid phase extraction with $C_{18}$ disks. An enrichment factor of 50 was achieved. The molar absorptivity of the chelate is $1.28{\times}10^5 L{\cdot}mol^{-1}{\cdot}cm^{-1}$ at 545 nm in measured solution. Beer's law is obeyed in the range of 0.01-3 ${\mu}$g/mL. The relative standard deviation for eleven replicates sample of 0.01 ${\mu}$g/mL is 1.65%. This method was applied to the determination of mercury in tobacco and tobacco additive with good results.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1224-1230
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• 2001

Single crystals of nanocomposite [GaO4Al12(OH)24(H2O)12][Al(OH)6Mo6O18]2(OH)${\cdot}$30H2O, 2, were obtained by the reaction between [GaO4Al12(OH)24(H2O)12]7+ and [Mo7O24]6- clusters in an aqueous solution, analogously to the [AlO4Al12(OH)24(H2O)12][Al(OH)6Mo6O18]2(OH)${\cdot}$29.5H2O nanocomposite, 1. The crystal structure of 2 was determined by single crystal x-ray diffraction; space group $C2}c$ (No. 15), a = 27.418(2) $\AA$, b = 15.647(2) $\AA$, c = 23.960(4) $\AA$, $\beta$ = $102.850(9)^{\circ}$, V = 10,021.5(20) $\AA3$ , Z = 4. Detailed analysis of the structural data show that the clusters are held by intimate hydrogen bondings of the surface O2- and OH- groups of the clusters as well as the ionic interactions between the oppositely charged cluster ions.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.25-31
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• 2006

'Meyer' zoysiagrass(Zoysia japonica Steud.) is a popular turfgrass species used for transition zone golf course fairways and tees in mfd U.S.A golf courses because it is generally winter hardy while providing an excellent playing surface with minimal chemical and irrigation inputs. However, its functionality declines easily in many of the shaded areas of these courses. Reduced irradiance causes excessive shoot elongation, reduced tillering, and weak plants that are poorly suited to tolerate or recover from traffic and devoting. Trinexapac-ethyl (TE) effectively reduces gibberellic acid (GA) biosynthesis and subsequent shoot cell elongation. This study was initiated to evaluate TE effect on shoot elongation and stand persistence under two levels of shade in 'Meyer' zoysiagrass. A mature stand of 'Meyer' was treated with all combinations of three levels of shade(0%, 79%, and 92%) and three levels of monthly TE [0, 48 $g{\cdot}ha^{-1}$ a.i(0.5x) and 96 $g{\cdot}ha^{-1}$ a.i(1x)]. In full sun, the TE at 48 $g{\cdot}ha^{-1}$ a.i reduced clipping yield by 18% over a four-week period and, whereas the TE at 96 $g{\cdot}ha^{-1}$ a.i by 30% to 38%. Monthly application of TE at the 96 $g{\cdot}ha^{-1}$ a.i increased 'Meyer' tiller density in full sun and under 79% shade. Both rates of TE consistently reduced shoot growth under shade relative to the shaded control. Only the monthly applications of the TE at 96 $g{\cdot}ha^{-1}$ a.i consistently delayed loss of quality under 79% shade. Our results indicate TE can be an effective management practice to increase 'Meyer' zoysiagrass persistence in shaded environments.

• Journal of Sasang Constitutional Medicine
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• v.18 no.3
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• pp.1-11
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• 2006

1. Objectives The purpose of this study is to find the kinds & meaninings of Qi in Lee Je-Ma's writings. 2. Methods We analyzed Lee Je-Ma's writings which contain the related contents of Qi's kinds & meanings 3. Results and Conclusions 1) There are distinctive Qi features of $sorrow{\cdot}anger{\cdot}joy{\cdot}pleasure$(哀怒僖樂) which are different from one of seven mode emotions(七情) in ${\ulcorner}$Gyukchigo(格致藁)${\lrcorner}$. 2) When $Water{\cdot}grain's$ Qi(臟氣) is the base of the human's Qi, $Nature{\cdot}emotion's$ Qi(性${\cdot}$情氣) is managing. And $Lung{\cdot}Spleen{\cdot}Liver{\cdot}Kidneys's$ Qi(肺脾肝腎氣) is the representative concept resulted by the complex operation of $Water{\cdot}grain's$ Qi(水穀之氣) and $Nature{\cdot}emotion's$ Qi. Each Qi stands for its protensity as follows ; Lung's Qi for extrorse propensity of Yang(Z), Spleen's Qi for upward propensity of Yang(陽), Liver's Qi for introrse propensity of Eum(陰), Kidneys's Qi for downward propensity of Eum(陰). 3) Jang's Qi is more important than medicine's Qi and medicine's Qi has a limitation about recovering jang's Qi. So that it is very important to take care of one's mind. 4) Controling mind Qi is controling Nature & emotion's Qi. Thus controling mind Qi si the best plan for jang's Qi and controling with medicine's Qi is the next policy. 5) Qi influences all aspect of personality, disease, application of medicines and ordinary symptoms. So that Qi is the kernel of the Sasang Constitutional Medicine.

• Korean Journal of Materials Research
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• v.15 no.12
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• pp.786-790
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• 2005

We investigated the particularity of temperature and composition changes in $xNa_2O{\cdot}(52.5-x)B_2O_3{\cdot}47.5SiO_2$ glasses by use of FT-IR, $^{11}B$ NMR, Raman spectrometer. From FT-IR and $^{11}B$ NMR spectrometer, we thought that tetrahedral boron, $BO_4$ units are created $N_4$ increasing tendency generated near $600^{\circ}C$. It's expected that composition ana heat treatment directly contributed to structural changes, this changes are following to $Na_2O$ increasing or decreasing. caused by $N_4\;and\;BO_4$ units are caused by relatively increasing or decreasing in the glasses' structure. Particularly, $BO_4$ units are converted to $BO_3$ units after $600^{\circ}C$ heat treatment for 50h in the composition of $x<18(R<0.5,\;R=Na_2O/B_2O_3\;mol\%)$. On the order hand, $BO_3$ units are converted to, $BO_4$ units after $600^{\circ}C$ heat treatment for 50h in the composition of $x{\geq}18\;(R>0.5)$. This particularity of composition and temperature dependence of structural changes are similarly represented by Raman analysis results.

• Korean Journal of Materials Research
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• v.18 no.2
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• pp.107-111
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• 2008

[ $BaO{\cdot}Nd_2O_3{\cdot}5TiO_2$ ] (BNT) ceramics modified with a borate glass containing Ba, Nd and Ti as glass constituents were investigated with regard to their sintering behavior and microwave dielectric properties. An addition of iso-component glass significantly improved the sinterabilty of the BNT ceramics and lowered the sintering temperature. A maximum density of $5.29\;g/cm^3$ and an x-y shrinkage of 17% were obtained for BNT ceramics containing 10wt.% of the glass sintered at $1100^{\circ}C$. The dielectric composition without the glass additive was only slightly densified at $1100^{\circ}C$. The resulting sample exhibited two crystalline phases, $BaNd_2Ti_5O_{14}$ and $Ba_2Ti_9O_{20}$, regardless of sintering temperature and glass content. When >10wt.% glass was added, exaggerated grain growth with a less uniform microstructure was found, resulting in the subsequent reduction of the fired density and the dielectric properties. BNT ceramics containing 10wt.% of the isocomponent glass sintered at $1100^{\circ}C$ for 4 h showed promising dielectric properties of k = 71.3 and Q = 1,330.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.363-367
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• 2004

For comparative analysis of the eubacterial community structure at 8 sampling sites throughout the Nak-Dong River, FISH (fluorescence in situ hybridization) method was employed. The total ratio of each determined eubacterial group such as ${\alpha}\;{\cdot}\;{\beta}\;{\cdot}\;{\gamma}-subclasses$proteobacteria and Cytophaga-Flavobacterium(CF) group to total counts(DAPI) at each site varied 9.3-42.5% with the highest value at uppermost part. And each ratio of determined eubacterial groups reached mostly under 10% except that of CF group (23%) at uppermost part. Furthermore, compared to lower part, upper part represented unexpectedly higher proportions of ${\gamma}-subclass$ proteobacteria comprised almost fast growing bacteria on degradable organics. Also the variations of ammonia-oxidizing bacteria ranged from $2.7{\times}10^4$ to $18.0{\times}10^4$ cells $mL^{-1}$ with the lowest value in lower part and the highest value in mid part whereas those of nitrite-oxidizing bacteria varied 5.2-7.7{\times}10^4$ cells $mL^{-1}$ without noticeable differences throughout the sites. Additionally, the ratio of nitrifying bacteria to total counts ranged from 1.0% to 13.6% with no differences between ammonia-oxidizing bacteria and nitrite-oxidizing bacteria. In conclusion, FISH method introduced in this study for monitoring, normally used for the quantitative analysis of bacteria, provided also good information on their environmental status in the Nak-Dong River.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.78-85
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• 2000

Leachate from acidogenic fermentation of food waste was effectively treated by the UASB reactor at $37^{\circ}C$. The efficiency of COD removal was consistently over 96% up to the loading rates of $15.8g\;COD/{\ell}{\cdot}d$. The methane production rate increased to $5.5{\ell}/{\ell}{\cdot}d$. Of all the COD removed, 92% was converted to methane and the rest presumably to biomass. At loading rates over $18.7g\;COD/{\ell}{\cdot}d$, the efficiency of COD removal decreased due to the sludge flotation and washout in the reactor, which resulted from short HRT of less than 10.6 hr. The SMA(specific methanogenic activity) analysis showed that the VFA-degrading activity of granule was the highest for butyrate, and the lowest for propionate. This result was consistent with the observation that the residual propionate concentration was the highest among the VFAs in the effluent. Typical granules were found to be mainly composed of microcolonies of Methanosaeta. Though the original seed sludge contained 64.3% of particles smaller than 1.4mm, the sludge particles had been growing during the fermentation, and at the final step of this study, 75.1% of the particles were found to be larger than 1.4 mm in the UASB reactor.

• Clean Technology
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• v.18 no.4
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• pp.398-403
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• 2012

Selective nitrification and granulation have been carried out in a pilot scale air-lift sequencing batch reactor (SBR) for stable and economical nitrogen removal from wastewater. The SBR showed about 100% nitrification efficiency up to 1.0 kg ${NH_4}^+-N/m^3{\cdot}d$, about 90% efficiency at 1.0-2.0 kg ${NH_4}^+-N/m^3{\cdot}d$, and it was less than 90% when the load was higher than 2.0 kg ${NH_4}^+-N/m^3{\cdot}d$. Nitrite accumulation was induced by selective inhibition of nitrite oxidizing bacteria by free ammonia inhibition and dissolved oxygen limitation. For the purpose, high nitrite ratio (> 0.95) was obtained by keeping the pH higher than 8.0 and dissolved oxygen lower than 1.5 mg/L. In addition, sludge granulation was achieved by keeping reactor settling time to 5 minutes to wash out poor settling sludge and to promote the growth of granulation sludge. The operation accelerated sludge granulation and the sludge volume index (SVI) decreased and stably maintained to less than 75 in 60 days.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.1
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• pp.47-56
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• 2009

Purpose: To find optimized luminosity factor of color from light transmission filter. Methods: To make $Y_{1-x}G_{x}$, $Y_{1-x}P_{x}$ by using CR-39 compound within dipping method, mixing up Y(Yellow), G(green) and P(pink) for optimize eye sensitivity. Modeling for relative luminous efficiency(relative sensitivity) curves in Luminose transmission, it could be resolved by Multiplying sensitivity of eye within transmission rate of Lens ($P_f({\lambda}=T({\lambda}){\cdot}P({\lambda}).)$.). To evaluate Wavelength between 400~700 nm, relative luminous efficiency curve in Area and Height value is being used. Results: In color filter of $Y_{1-x}G_{x}$ position of x equals to 0.04, 0.1, 0.08, 0.12, 0.14, 0.5 at ${\beta}=S_1/S_0{\cdot}100$ each consist value of 76.1, 77.9, 80.7, 81.6, 80.2, 18.6 In color filter of $Y_{1-x}P_{x}$ position of x equals to 1.00, 0.2, 0.6, 0.8 at ${\beta}=S_1/S_0{\cdot}100$ each consist value of 74.3, 74.0, 70.5, 33.0 The result from experiment $Y_{1-x}P_{x}$ value less than $Y_{1-x}G_{x}$, from evaluating luminous efficiency curve and test was successfully optimized. Conclusions: Optimized relative luminous efficiency curve result have value of X=0.12-0.14 at $Y_{1-x}G_{x}$.