• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.511-516
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• 1992

The x-values of the nonstoichiometric compound YbO$_x$ have been measured in a temperature range of 600 to 1150$^{\circ}C$ under oxygen partial pressure of 1.00 ${\times}$ 10$^{-2}$ atm∼atmospheric air pressure. The values are varied between 1.55453 and 1.60794 in the conditions. The enthalpy of the formation for x' in YbO$_{1.5＋x'}$(${\Delta}$H$_f$) was 1.55, 1.18, and 1.05 kJ/mol under the above conditions, respectively. The electrical conductivities of the oxides or ${\sigma}$ have been measured in the temperature range from 600 to 1100$^{\circ}C$ under oxygen partial pressure of 1.00 ${\times}$ 10$^{-5}$ ∼ 2.00 ${\times}$ 10$^{-1}$ atm. They varied from 10$^{-9}$ to 10$^{-5}$ ohm$^{-1}$ cm$^{-1}$ within the semiconductor range. The Arrhenius plots of the electrical conductivities show a linearity and the activation energy for the conduction was about 1.7eV. The oxygen partial pressure dependence of the conductivity or 1/n value increases with the pressure. The nonstoichiometric conduction mechanism of the oxide was discussed in terms of the x values, ${\sigma}$ values, and the thermodynamic data.

• Journal of the Korean Chemical Society
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• v.61 no.4
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• pp.163-167
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• 2017

Along with the progress of white LED technology, red phosphors have become increasingly important in industry and academia, and a more specific demand has steadily increased in the market. Red phosphors are used in high efficiency and high rendering LED lightings. However, using red phosphors with $Eu^{2+}$ activators caused color rewarming and reduced emission intensity in white LED chips due to strong reabsorption in the green or yellow wavelength range caused by the 4f-5d transition. $Mn^{4+}$ doped phosphors which have no such drawbacks and which can further improve the color rendering index (CRI) are now of great interest. However, $Mn^{4+}$-doped phosphors have a disadvantage in that the emission wavelength is determined depending on the host due to the $^2E_g{\rightarrow}^4A_2$ transition. In this study, the $SrO-BaO-GeO_2$ solid-solution was selected, and $Sr_{1-x}B_axGe_4O_9:Mn^{4+}{_{0.005}}$ ($0{\leq}x{\leq}1$) phosphors were synthesized and characterized. This led to a versatile color tuning in LED technology.

• Journal of Sericultural and Entomological Science
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• v.8
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• pp.11-25
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• 1968

Various formulae for estimation of leaf production in mulberry trees were investigated and obtained. Four varieties of mulberry trees were used as the materials, and seven characters namely branch length. branch diameter, node number per branch, total branch weight, branch weight except leaves, leaf weight and leaf area, were studied. The formulae to estimate the leaf yield of mulberry trees are as follows: 1. Varietal differences were appeared in means, variances, standard devitations and standard errors of seven characters studied as shown in table 1. 2. Y$_1$=a$_1$X$_1$${\times}$P$_1$......(l) where Y$_1$ means yield per l0a by branch number and leaf weight determination. a$_1$.........leaf weight per branch. X$_1$.......branch number per plant. P$_1$........plant number per l0a. 3. Y$_2$=(a$_2$${\pm}$S. E.${\times}$X$_2$)+P$_1$.......(2) where Y$_2$ means leaf yield per l0a by branch length and leaf weight determination. a$_2$......leaf weight per meter of branch length. S. E. ......standard error. X$_2$....total branch length per plant. P$_1$........plant number per l0a as written above. 4. Y$_3$=(a$_3$${\pm}$S. E${\times}$X$_3$)${\times}$P$_1$.....(3) where Y$_3$ means of yield per l0a by branch diameter measurement. a$_3$.......leaf weight per 1cm of branch diameter. X$_3$......total branch diameter per plant. 5. Y$_4$=(a$_4$${\pm}$S. E.${\times}$X$_4$)P$_1$......(4) where Y$_4$ means leaf yield per 10a by node number determination. a$_4$.......leaf weight per node X$_4$.....total node number per plant. 6. Y$\sub$5/= {(a$\sub$5/${\pm}$S. E.${\times}$X$_2$)Kv}${\times}$P$_1$.......(5) where Y$\sub$5/ means leaf yield per l0a by branch length and leaf area measurement. a$\sub$5/......leaf area per 1 meter of branch length. K$\sub$v/......leaf weight per 100$\textrm{cm}^2$ of leaf area. 7. Y$\sub$6/={(X$_2$$\div$a$\sub$6/${\pm}$S. E.)}${\times}$K$\sub$v/${\times}$P$_1$......(6) where Y$\sub$6/ means leaf yield estimated by leaf area and branch length measurement. a$\sub$6/......branch length per l00$\textrm{cm}^2$ of leaf area. X$_2$, K$\sub$v/ and P$_1$ are written above. 8. Y$\sub$7/= {(a$\sub$7/${\pm}$S. E. ${\times}$X$_3$)}${\times}$K$\sub$v/${\times}$P$_1$.......(7) where Y$\sub$7/ means leaf yield estimates by branch diameter and leaf area measurement. a$\sub$7/......leaf area per lcm of branch diameter. X$_3$, K$\sub$v/ and P$_1$ are written above. 9. Y$\sub$8/= {(X$_3$$\div$a$\sub$8/${\pm}$S. E.)}${\times}$K$\sub$v/${\times}$P$_1$.......(8) where Y$\sub$8/ means leaf yield estimates by leaf area branch diameter. a$\sub$8/......branch diameter per l00$\textrm{cm}^2$ of leaf area. X$_3$, K$\sub$v/, P$_1$ are written above. 10. Y$\sub$9/= {(a$\sub$9/${\pm}$S. E.${\times}$X$_4$)${\times}$K$\sub$v/}${\times}$P$_1$......(9) where Y$\sub$7/ means leaf yield estimates by node number and leaf measurement. a$\sub$9/......leaf area per node of branch. X$_4$, K$\sub$v/, P$_1$ are written above. 11. Y$\sub$10/= {(X$_4$$\div$a$\sub$10/$\div$S. E.)${\times}$K$\sub$v/}${\times}$P$_1$.......(10) where Y$\sub$10/ means leaf yield estimates by leaf area and node number determination. a$\sub$10/.....node number per l00$\textrm{cm}^2$ of leaf area. X$_4$, K$\sub$v/, P$_1$ are written above. Among many estimation methods. estimation method by the branch is the better than the methods by the measurement of node number and branch diameter. Estimation method, by branch length and leaf area determination, by formulae (6), could be the best method to determine the leaf yield of mulberry trees without destroying the leaves and without weighting the leaves of mulberry trees.

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.794-798
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• 1996

Solid solutions of the nonstoichiometric Dy1-xSrxCoO3-y system with the compositions of x=0.00, 0.25, 0.50, 0.75, and 1.00 have been synthesized by the solid state reaction at 1000 ℃ under atmospheric air pressure. The crystallographic structures of the solid solutions are analyzed by the powder X-ray diffraction patterns at room temperature. The analyses assign the compositions of x=0.00 and 0.25 to the orthorhombic system with space group of Pbnm/D2h16, the compositions of x=0.50 and 0.75 to the tetragonal system like a typical SrCoO2.86, and the composition of x=l.00 or SrCoO2.50 to the brownmillerite type system with space group of I**a. The reduced lattice volumes increase with x value due to the larger radius of Sr2+ ion than that of Dy3+ ion. The mole ratio of Co4+ ion to total Co ion with mixed valence state between Co3+ and Co4+ ions at B sites or τ value has been determined by an iodometric titration. All the samples except for the DyCoO3 compound show the mixed valnce state and thus the composition of x=0.50 has the maximum τ value in the system. The oxygen vacancies increasing with x value are randomly distributed over the crystal lattice except for the composition of x=l.00 which have the ordering of the oxygen vacancies. The nonstoichiometric chemical formulas of the Dy1-xSrxCo3+1-τCo4+τO3-(x-τ)/2 system are formulated from the x, τ, and y values. The electrical conductivity in the temperature range of 100 to 900 K increases with τ value linearly because of positive holes of the Co4+ ions in π* band as a conducting carrier. The activation energy of the x=0.50 as Ea=0.17 eV is minimum among other compouds. Broad and high order transition due to the overlap between σ* and π* bands broadened by the thermal activation is observed near 1000 K and shows a low temperature-semiconducting behavior. Magnetic properties following the Currie-Weiss law show the low to high spin transition in the cobaltate perovskite. Especially, the composition of x=0.75 presents weak ferromagnetic behavior due to the Co3+-O2--Co4+ indirect superexchange interaction.

• Journal of Korean Academy of Nursing
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• v.35 no.3
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• pp.487-493
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• 2005

Purpose: The purpose of this study was to identify the effects of hand acupuncture therapy on intermittent abdominal pain in children. Method: A quasi experimental pre-test and post (1,2)-test design was used. Data was collected from May, 2002 to February, 2003. Forty children were assigned to the experimental (20) or control group (20). The experimental group received Hand-Acupuncture therapy on the meridian point; A8, A9, A10, All, A12, E22, E45 for 20 minutes, while the control group rested on the bed. Data was analyzed using the SAS program with Fisher's Exact $x^2$ test, repeated measured ANOVA, and ANCOVA. Result: In the experimental group, pain intensity (f=63.26, p=0.00), A12(A)(F=60.40, p=0.00), and medication requirement ($x^2$=32.63, p=0.00) were significantly lower than that of the control group. Conclusion: These findings indicate that hand acupuncture therapy is effective for reduction of intermittent abdominal pain. Therefore, hand acupuncture therapy can be considered an independent nursing intervention for reducing intermittent abdominal pain.

• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.394-401
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• 2017

PURPOSE. The purpose of this study was to compare the optical properties of pre-colored dental monolithic zirconia ceramics of various thicknesses sintered in a microwave and those in a conventional furnace. MATERIALS AND METHODS. A2-shade of pre-colored monolithic zirconia ceramic specimens ($22.0mm{\times}22.0mm$) in 3 thickness groups of 0.5, 1.0, and 1.5 mm were divided into 2 subgroups according to the sintering methods (n=9): microwave and conventional sintering. A spectrophotometer was used to obtain CIELab color coordinates, and translucency parameters and CIEDE2000 color differences (${\Delta}E_{00}$) were measured. The relative amount of monoclinic phase ($X_m$) was estimated with x-ray diffraction. The surface topography was analyzed by atomic force microscope and scanning electron microscope. Statistical analyses were conducted with two-way ANOVA (${\alpha}=.05$). RESULTS. There were small interaction effects on CIE $L^*$, $a^*$, and TP between sintering method and thickness (P<.001): $L^*$ (partial eta squared ${{\eta}_p}^2=0.115$), $a^*$ (${{\eta}_p}^2=0.136$), and TP (${{\eta}_p}^2=0.206$), although higher $b^*$ values were noted for microwave sintering regardless of thickness. Color differences between two sintering methods ranged from 0.52 to 0.96 ${\Delta}E_{00}$ units. The $X_m$ values ranged from 7.03% to 9.89% for conventional sintering, and from 7.31% to 9.17% for microwave sintering. The microwave-sintered specimen demonstrated a smoother surface and a more uniform grain structure compared to the conventionally-sintered specimen. CONCLUSION. With reduced processing time, microwave-sintered pre-colored dental monolithic zirconia ceramics can exhibit similar color perception and translucency to those by conventional sintering.

• Journal of the Korean Magnetics Society
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• v.9 no.1
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• pp.7-16
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• 1999

Stoichiometric and nonstoichiometric $Y_{3-x}Fe_{5+x}O_{12})$ polycrystalline samples (x=0.00, 0.05, 0.10, 0.30, -0.05, -0.10, -0.30) were prepared by solid state reaction method. The magnetic properties of the sample were investigated by FMR (ferromagnetic resonance) technique at microwave frequency 5.11 GHz (G-band) and 23.39 GHz (K-band) respectively. The spectroscopic splitting factor g were estimated to be 2.04~2.35 from the derivative absorption lines. As the samples became yttrium $(Y^{3+})$ excess and iron $(Fe^{3+})$ excess, Magnetizations were decreased. But resonance linewidth were increased. To investigate the anisotropy, the angular dependence of resonance magnetic fields were measured. Angular dependence of effective magnetizations were measured by FMR from 77 K to 300 K at K-band microwave frequency (23.39 GHz) and the saturation magnetizations were measured by VSM. The Bloch coefficients B and C were determined by fitting. $M_{eff}(0)$ was obtained by the extrapolation from 80 K. From this result, the spin wave stiffness constant D $(about\; 162~206 \;eV{\AA}^2)$and average square range of exchange interaction $$$(about \;5.84~12.13\;{\AA}^2)$ were determined.

• Journal of Yeungnam Medical Science
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• v.5 no.1
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• pp.93-100
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• 1988

In clinical practice, creatinine clearance(Ccr) remains the most commonly used laboratory assessment of glomerular function despite methodological and technical problems of urine collection. Schwartz et al. in 1976, reported that an accurate estimate of glomerular filtration rate(GFR) could be obtained from the simple determinations of plasma creatinine(Pcr) and body length(L) : GFR($m{\ell}/min/1.73m^2$=k L(cm)/Pcr(mg/$100m{\ell}$), (k=constant). The subject of this study were ill children admitted to our pediatric department from July, 1985 to June, 1987 and they were divided into three groups; group I, from 1 to 5 years old, group II, from 6 to 10 years old, group III. from 11 to 15 years old. The results were as following ; 1) Measured creatinine clearance($Ccr_M$, $m{\ell}/min/1.73m^2$) were $109.73{\pm}9.97$ in group I, $108.26{\pm}9.02$ in group II, $96.20{\pm}4.72$ in group III and $105.48{\pm}5.23$ in all age group. 2) Measured k($k_M$) obtained from $Ccr_M=k$ Ht/Pcr were $0.49{\pm}0.03$ in group I, $0.48{\pm}0.02$ in group II, $0.43{\pm}0.02$ in group III, and $0.47{\pm}0.02$ in all age group.(Ht ; height) 3) Linear equations and correlation coefficients between Ht/Pcr(x) and Ccr(y) were y=0.822x-65.63(r=0.99) in group I, y=0.61x-23.46(r=0.72) in group II, y=0.18x+54.44(r=0.54) in group III and y=0.58x-22.13(r=0.81) in all age group. 4) $Ccr_E$ was again estiamted from linear equations between Ht/Pcr and $Ccr_M$ and $k_E$ was calculated with Ht/Pcr and $Ccr_E$ were $0.48{\pm}0.01$ in group I, $0.49{\pm}0.01$in group II, $0.43{\pm}0.01$ in group III and $0.47{\pm}0.00$ in all age group. 5) Consistant values of $k_E$ and $k_M$ were highly significant as 95~97.5% in group I and II, 90~95% in group III and 97.5~99% in all age group. In summary, we could estimate GFR with height, plasma creatinine and measured k($k_M$) according to the age in easy and rapid way.

• Journal of Korean Academy of Nursing Administration
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• v.6 no.3
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• pp.375-388
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• 2000

This study was attempted to help in explore new direction about Clinical Classification System of the pediatric patients visiting emergency center. Data were collected from 276 patients who visited emergency center of E University Hospital during 3 months period form March 1, to May 31, 1999. The results were as follows: 1. Distribution of pediatric patients according to Clinical Classification System, class I(59.9%) topped followed by class II(23.9%), class III(14.1%), class IV(2.0%). Average score of pediatric patients according to Clinical Classification System showed class I.00, class II .02, class III .05, class IV .07. and total mean score of items lowed averaged .01. 2. With the resepect to the Clinical Classification System according to the pediatric patients visiting emergency center, there were stastically significant difference in visiting time($x^2=27.839$, P=.023), experience of admission($x^2=11.365$, p=.010), disease classification($x^2=89.998$, p=.000), state of airway patency($x^2=18.781$, p=.000), consciousness level($x^2=59.774$, p=.000), period of symptom manifestation($x^2=34.112$, p=.000), pediatric patients protector's thinking about pediatric patients state($x^2=49.998$, p=.000), treatment outcome($x^2=72.278$, p=.000), duration of stay at emergency center($x^2=103.062$, p=.000). 3. There were significant correlation between the state of pediatric patients and Clinical Classification System(r=.530, p=.000).

• Fisheries and Aquatic Sciences
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• v.20 no.10
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• pp.26.1-26.9
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• 2017

Fishes in genus Sardinella are small pelagic species, which plays an important role in marine ecosystem as the first consumer. Those species are also commercially important, whose total catch reaches 278,600 tons in 2011 in Indonesia, but their identification has been difficult for their morphological similarity. In this study, we reported Sardinella jussieu for the first time in Indonesian coastal area (Banten Bay, Indonesia, $6^{\circ}\;0^{\prime}\;50.00^{{\prime}{\prime}}\;S-106^{\circ}\;10^{\prime}\;21.00^{{\prime}{\prime}}\;E$). We were able to confirm the species by both its morphological characteristics including the black spot at dorsal fin origin, the dusky pigmentation at caudal fin, 31 total scute numbers, and DNA sequence identity in the GenBank database by the molecular analysis. Its total mitochondrial genome was determined by the combination of next-generation sequencing and typical PCR strategy. The total mitochondrial genome of Sardinella jussieu (16,695 bp) encoded 13 proteins, 2 ribosomal RNAs, 22 transfer RNAs, and the putative control region. All protein-coding genes started with ATG and typical stop codon and ended with TAA or TAG except for ND4 in which AGA is used. Phylogenetic analyses of both COI region and full mitochondrial genome showed that S. jussieu is most closely related to Sardinella albella and Sardinella gibbosa