• The Korean Journal of Zoology
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• v.33 no.3
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• pp.337-345
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• 1990

The properties of three esterases (E2, E6 and E11) which were previously purified from Pieris rapae L. were determined and physiological role of E6 was inferred using immunological methods. Based on inhibitor study, all of the purified esterases were found to be carboxylesterases (EC 3.1.1.1). The Km values for E2, E6 and E11 were determined to be 6.89 X 10-$^4$M. 3.19 $\times$ l0-$^4$M and 3.69 X 10-$^4$M, respectively. The molecular weights of E2, E6 and E11 were estimated to be 42 KD, 81 KD and 174 KD, respectively. The isoelectric points of E2, E6 and E11 were estimated to be pH 5.54, pH 5.89 and pH 6.50, respectively. The concentration of E6 during development was highest at the late 5th instar larval stage and that according to organs at the same stage was highest in midgut. These results suggest that E6 might be a hydrolase involved in the digestion of dietary lipids.

• Geomechanics and Engineering
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• v.31 no.4
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• pp.385-393
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• 2022

Previous studies postulated insignificant capillary rise (h_c) effect above the water table (H_w) for unsaturated soils. In addition, these studies utilised dry unit weight above H_w. This paper, therefore, addresses the effect of these postulations on strength where the influence of h_c using a modified upper bound approach, Discontinuity Layout Optimization (UNSAT-DLO) for a simulated soil was predicted. Two different parametric studies to model passive earth pressure and bearing capacity problems are carried out to provide an insight into the effect of capillary rise on strength. Significant increase in strength, owing to unsaturated conditions, was obtained where the maximum increase was when suction slightly less or greater than the air entry suction. On the other hand, the results showed a negative effect of h_c. For example, up to 8.24% decrease in passive thrust (P_p) was obtained at H_w=0 m when h_c rose 1 m from 0 m. To put this into perspective, this was equivalent to a decrease of about 2° in 𝜙 at H_w=0 m and h_c =0 m in order to obtain the same result at h_c =1 m. For the bearing capacity problem, the effect was seen to be higher, up to 18.4% decrease in N_𝛾 was obtained when h_c rose from 0 m to 2.5 m at H_w =0 m. In addition, the results revealed a negative influence of assigning dry unit weight above H_w or h_c.. However, considerable increase in strength was obtained when unsaturated unit weight above h_c was assigned.

• Journal of Korean Physical Therapy Science
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• v.10 no.1
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• pp.65-73
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• 2003

The purpose of this study was to determine whether neuromuscular electrical stimulation(NMES), applied over the antagonist or the agonist, would alter the H reflex. Attention was focused on the roles of stimulus location. We used normal eight subjects without neuromuscular disease which were divided into 3 groups; the subjects were diveded into group of antagonist, agonist, antagonist-agonist. All groups were meted of eight subjects. Neuromuscular electrical stimulation was administered for 15 minutes. All subjects were subjected to three tests, including a pre-test, post-test and post-20 minute test. The data were analyzed by repeated measures ANOVA and paired t-test. The results were as follows; 1. H latencies were significantly increased in agonist and antagonist-agonist group (p<.01). 2. H/M intervals were significantly increased in agonist and antagonist-agonist group (p<.01). 3. H amplitudes were significantly increased in agonist (p<.001) and antagonist-agonist group (p<.01). 4. H/M ratios were significantly decreased in agonist and antagonist-agonist group (p<.01). In agonist group. H-reflex amplitudes and H/M ratios were more significantly decreased than antagonist group. Future studies will need to determine what influence NMES may have on the excitability of spinal motor neurons in people having UMN syndrome.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.1
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• pp.52-61
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• 1997

This study was aimed to decrease AOX(Adsorbed Organic Halide Compounds) by applying bleaching methods of A(HNO$_3$ ＋ NaNO$_2$) and $D^{(H/L)}$(dual pH chlorine dioxide bleaching) to conventional OCEDED bleaching stages. And so we investigate the effects of NSA treatment and the influence of production rate of ion species in chlorine dioxide and pulp mixtures according to various pH as well as dual pH on pulp bleaching. Finally the effects of AOC_DED^{(H/L)}ED^{(H/L)}$ bleaching stage were investigated by measuring AOX, brightness, kappa number and viscosity of pulps. A stage was treated by using 4% $HNO_3$ and 0.05~2.0% $NaNO_2$ on pulp and $D^{(H/L)}$ stage was like that pulp mixed with chlorine dioxide solution was adjusted at pH 7.0 and reacted in pulp cosistency 3%, S~20min, $70^{\circ}C$, and then successively for 160~175min at pH 4.0. It was found that suitable $NaNO_2$ addition rate was at 0.6% where the brigtness of pulp was most higher and pulp viscosity was not decreased much. Chlorate ($CIO_3$) was decreased according to pH increase but chlorite($CIO_2$) was highly decreased according to pH increase. And chloride was slightly increased with pH increase. The applying of A and D^{(H/L)}$ bleaching stages to some various multiple bleaching stages ($AOC_DED^{(H/L)}/EopD^{(H/L)} etc.$) had good results that brightness was increased more 2~3% ISO than conventional method(OCEDEopD), but viscosity was dropped by only 1~2cps.

• Membrane and Water Treatment
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• v.7 no.5
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• pp.403-416
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• 2016

The possibility of using carica papaya leaf powder for removal of copper from wastewater as a low cost adsorbent was explored. Different parameters that affect the adsorption process like initial concentration of metal ion, time of contact, adsorbent quantity and pH were evaluated and the outcome of the study was tested using adsorption isotherm models. A maximum of 90%-94.1% copper removal was possible from wastewater having low concentration of the metal using papaya leaf powder under optimum conditions by conducting experimental studies. The biosorption of copper ion was influenced by pH and outcome of experimental results indicate the optimum pH as 7.0 for maximum copper removal. Copper distribution between the solid and liquid phases in batch studies was described by isotherms like Langmuir adsorption and Freundlich models. The adsorption process was better represented by the Freundlich isotherm model. The maximum adsorption capacity of copper was measured to be 24.51 mg/g through the Langmuir model. Pseudo-second order rate equation was better suited for the adsorption process. A dynamic mode study was also conducted to analyse the ability of papaya leaf powder to remove copper (II) ions from aqueous solution and the breakthrough curve was described by an S profile. Present study revealed that papaya leaf powder can be used for the removal of copper from the wastewater and low cost water treatment techniques can be developed using this adsorbent.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.627-632
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• 2003

The pH dependence of the kinetic parameters of recombinant acetohydroxy acid synthase catalyzed reaction was determined in order to obtain information about the chemical mechanism, particularly acid-base chemistry. The maximum velocity and V/K for pyruvate were bell-shaped with estimated pK values of 6.5-6.7 and 8.6-8.9, respectively. The maximum velocity and V/K for 2-ketobutyrate were also bell-shaped with estimated pK values of 6.6-7.0 and 8.4-8.6. The pH dependence of 1/Ki for 3-bromopyruvate, a competitive inhibitor of pyruvate, was also bell-shaped, giving pK values almost identical with those obtained for pyruvate. Since the same pK values were observed in the $pK_{i 3-bromopyruvate}$, V/K pH profiles and $V_{max}$ profiles, both enzyme groups must be in their optimum protonation state for efficient binding of reactants. These results reflect that two enzyme groups are necessary for binding of substrate and/or catalysis.

• Journal of Sericultural and Entomological Science
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• v.34 no.2
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• pp.52-57
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• 1992

Using the new type auxiliary(K-1), dyeing experiment was done at the various dyeing conditions and the effects of auxiliary on the dyeing properties of acid milling dye for the silk fiber were dicussed. The results obtained were as follows; 1. The exhaust rate of acid milling dye was increased according to the auxiliary concentration at dyebath pH 7, But the increasing tendency of exhaust rate was decreased above auxiliary concentration 3% o. w. f.. 2. It was the same tendency of exhaust rate at dyebath pH 5, but the diffusion was more powerful at dyebath pH 7 than pH 5. 3. The decreasing ratio of exhaust rate according to dye concentration increasing was lower at auxiliary addition than auxiliary non-addition. 4. The exhaust rate curve according to increasing dyeing temperature showed the inflection point at auxiliary non-addition, but it was not observed in auxiliary addition. Consequently, it seems to be avoid that the occurrence of uneven dyeing at auxiliary addition.

• Resources Recycling
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• v.12 no.4
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• pp.38-43
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• 2003

Phosphate is an essential material for the growth of organisms. However. since relatively small amount is required. a large amount of phosphate is abandoned in wastes and wastewater. which contaminate the ecological environment including aquatic system. Purpose of this study is to treat especially high concentrated phosphate wastewater by use of calcium precipitation method. The pH range considered was from 6 to 12 and the maximum removal of phosphate was attained at pH 12. The con-centration of phosphate was observed to decrease rapidly until a half amount of calcium ion to its equivalent for the formation of calcium phosphate precipitate was added. which resulted in the decrease of the remaining concentration of phosphate down to 0.0027 mM. The effect of fluoride ion was examined and the concentration ratio between the phosphate and fluoride ion did not have any significant influence on the removal efficiency of phosphate. The effect of pH was also investigated. With the increasing of the pH in solution, the removal rate of phosphate was increased. Also it was investigated that the effect of fluoride on the phosphate removal was not significant.

• Journal of Plant Biology
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• v.19 no.3
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• pp.85-91
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• 1976

A comparison betwen the productivity of Pinus rigida which is native in the Eastern United States, and P. rigitaeda which is F1 hybrid between P. rigida and P. taeda, has been established. For each tree the diameter at breast height (D) and the height of tree (H) were measured in three years. The standard sample trees were down and then weighed each organ. From obtained data the allometric relation between $D_2H$ and dry weight of the trunk (Ws), the branches (Wb) and the leaves (Wl) of P. rigida were approxmated by $$Ws=0.0592 (D^2H)^{0.837}$$ $$Wb=0.0065 (D^2H)^{0.989}$$ $$Wl=0.0447(D^2H)^{0.690}$$ and those of P. rigitaeda were approximated by $$Ws=0.0522 (D^2H)^{0.843}$$ $$Wb=0.0037 (D^2H)^{1.117}$$ $$Wl=0.0207 (D^2H)^{0.856}$$ From the above, the standing crops of above ground of P. rigida were estimated to be as much as 16.93-34.35 ton dry matter per ha, and those of P. rigitaeda were 20.45-45.55 ton per ha. Annual net production was appraised at 8.07-9.35 ton/ha.yr in P. rigida and at 11.59-13.41 ton/ha.yr in P. rigitaeda (1.0:1.4). It is assumed that high productivity of P. rigitaeda stand compared with P. rigida resulted from an increase of the leaf amount with age. Photosynthetic ability under the saturated light of the current and theold leaves of P. rigida were respectively 2.62 and 0.66mg CO2/g. d. wt..hr and those of P. rigitaeda were 1.17 and 0.96mg CO2/g.d. wt.hr. Respiration of the current and the old leaves at $25^{\circ}C$ were 1.00 and 0.90 mg CO2/g. d. wt..hr. in P. rigida and 0.90 and 0.45mg CO2/g.d.wt.hr in P. rigitaeda. It is assumed that photosynthetic longevity of P. rigitaeda leaves was vigorously maintained longer than that of P. rigida.

• Korean Journal of Microbiology
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• v.17 no.2
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• pp.58-64
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• 1979

Studies on some properties of cellulase isolated from Piricularia oryzae. Crude cellulases were prepared from dried rice plant powder (Tong-il, Pal-dal) culture of P. oryzae(N-2, C-8, T-2). The best yield of enzyme was obtained from the medium using Tong-il rice plant powder for P. oryzae cav. N-2 and 2%-sucrose concentration in preculture media. Two units of the enzyme were incubated at $60^{\circ}C$ for 1 hour with 1.0ml, 0.6% Na-CMC. The optimum temperature for the enzyme activity was at $60^{\circ}C$ and the optimum pH was at pH4.0. When Na-CMC was used as substrate the $K_m$ values of crude enzyme were calculated to be $1.05{\times}10^{-4}\;mM\;and\;V_{max}$ was 2.8 mmole/hour. A 10-fold partial purification was achieved by $(NH_4)_2SO_4$ precipitation followed by column chromatography on DEAE Sephadex A-25.