• Bulletin of the Korean Chemical Society
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• v.24 no.2
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• pp.193-196
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• 2003

Nucleophilic addition reactions of benzylamines $(XC_6H_4CH_2NH_2)$ to benzylidene Meldrum's acids (BMA; $YC_6H_4CH=C(COO)_2C(CH_3)_2$) have been investigated in acetonitrile at 20.0 ℃. The rates of addition are greatly enhanced due to the abnormally high acidity of Meldrum's acid. The magnitudes of the Hammett $({\rho}_X\;and\;{\rho}_Y)$ and Bronsted $({\rho}_X$)$ coefficients are rather small suggesting an early transition state. The sign and magnitude of the cross-interaction constant, ${\rho}_{XY}$ (= -0.33), and kinetic isotope effects $(k_H/k_D\;{\stackrel}{~}{=}\;1.5-1.7)$ involving deuterated benzylamine nucleophilies $(XC_6H_4CH_2ND_2)$ are indicative of hydrogen-bonded cyclic transition state. The activation parameters, ${\Delta}H^{\neq}\;{\stackrel}{~}{=}\;4\;kcal\;mol^{-1}\;and\;{\Delta}S^{\neq}\;{\stackrel}{~}{=}\;-37\;e.u.$, are also in line with the proposed mechanism.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.34-37
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• 2001

In this study, the capacitance-voltage properties of $(Sr_{1-x}\cdot Ca_x)TiO_3(0.05{\leq}x{\leq}0.20)$-based grain boundary layer ceramics were investigated. The ceramics were fabricated by the conventional mixed oxide method. The sintering temperature and time were $1480\sim1500^{\circ}C$ and 4 hours. respectively. The 2nd phase formed by the thermal diffusion of CuO from the surface leads to very excellent dielectric properties, that is, ${\varepsilon}_r$ >50000, tan$\delta$ <0.05, ${\Delta}C$ < ${\pm}10%.$ The capacitance is almost unchanged below about 20[V] but it decreases slowly about 20[V]. The results of the capacitance-voltage properties indicated that the grain boundary was composed of the continuous insulating layers.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.11
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• pp.879-884
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• 2001

In this paper, the structural and dielectric properties of (Sr$_{l-x}$Ca$_{x}$)TiO$_3$ (0$\leq$x$\leq$0.2) -based grain boundary layer ceramics were investigated by XRD, SEM and HP4194A. The ceramics were fabricated by the conventional mixed oxide method. The sintering temperature and time were 1420~152$0^{\circ}C$ and 4 hours, respectively. The average grain size and the lattice constant were decreased with increasing content of Ca. The average grain size was increased with increase of sintering temperature. The relative density of all specimens was 96~98%. The 2nd Phase formed by the thermal diffusion of CuO from the surface leads to very excellent dielectric properties, that is, $\varepsilon$$_{r}$>50000, tan $\delta$<0.05, $\Delta$C<$\pm$10%. The appropriate Ca content was under 15 ㏖%.s under 15 ㏖%.%.

• Journal of Acupuncture Research
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• v.21 no.1
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• pp.226-239
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• 2004

Objective: Purpose of this study was to examine the effect of electroacupuncture(EA) at Xingjian(LR2) as 'Fire(火)' point of The Leg Absolute Um Liver Meridan(足厥陰肝經 : Chok-Kworum-Kan-Kyong) on the facial thermal change. Methods: Subjects of this study were 15 patients with upperpart(includes head and facial part) fever of human body and two examinations were carried out in each other day. We divided cases of two examinations into two groups. One is experimental group(N=15) that was carried out electroacupuncture stimulation at Xingjian(LR2), the other is control group(N=15) which was carried out electroacupuncture stimulation at optional point(in space between 1st and 2nd fingers) except acupuncture points of 12 meridians. We took the temperature of fixed areas on face by digital infrared thermal image(D.I.T.I.) before and after electroacupuncture stimulation. Those fixed areas on face that was taken temperature are Jingming(BL1), Sibai(ST2), Dicang(ST4), Indang, Shuigou(GV26), Chengjiang(CV24) areas. In cases of temperature of Jingming(BL1), Sibai(ST2), Dicang(ST4) areas, we applied each mean of left and right temperature to statical analysis. Results: In the group of electroacupuncture stimulation at Xingjian(LR2), temperature of every fixed areas on face fell: Jingming(BL1) area's ${\Delta}T=-0.7007{\pm}0.78642$, Sibai(ST2) area's ${\Delta}T=-0.6280{\pm}0.56439$, Dicang(ST4) area's ${\Delta}T=-0.5940{\pm}0.60179$, Indang area's ${\Delta}T=-0.7200{\pm}0.64515$, Shuigou(GV26) area's ${\Delta}T=-0.6160{\pm}0.80487$, Chengjiang(CV24) area's ${\Delta}T=-0.5627{\pm}0.72615$. In Xingjian(LR2) electroacupuncture group, each temperature of Jingming(BL1), Sibai(ST2), Indang areas showed a drop significantly in comparison with control group (p<0.05). But each temperature of Dicang(ST4), Shuigou(GV26), Chengjiang(CV24) areas did not showed a drop significantly in comparison with control group(p>0.05). Conclusions: The results mentioned above showed that electroacupuncture stimulation at Xingjian(LR2) significantly decreased the temperature on face of patients with upperpart fever of human body. In Xingjian(LR2) electroacupuncture group, especially temperature of upper part of face includes eye, cheekbone, forehead regions showed a drop significantly in comparison with control group.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.12
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• pp.781-785
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• 2016

With trend of the miniaturization and the high-functionalizing of mobile communication system, low-loss microwave dielectric materials are widely used for high frequency communication components. These dielectric materials should be co-sintered with highly electric-conducting metal such as silver or copper for high-frequency and thick film process application. Sintering temperature of $Ca(Li_{1/3}Nd_{2/3})_{0.2}Ti_{0.8}]O_{3-{\delta}}$, which has excellent dielectric properties such as ${\varepsilon}_r$ above 40, quality factor ($Q{\cdot}f_0$) above 16,000 GHz, and TCF (temperature coefficient of resonant frequency) of $-20{\sim}-10ppm/^{\circ}C$, is reported as high as $1,175^{\circ}C$, so it could not be co-sintered with silver or copper. Therefore in this study, low-temperature melting glasses of Zn-B-O and Zn-B-Si-O systems were added to $Ca[(Li_{1/3}Nb_{2/3})_{0.8}Ti_{0.2}]O_{3-{\delta}}$ to lower its sintering temperature under $900^{\circ}C$ without losing excellency of dielectric properties. With 15 weight % of Zn-B-Si-O glass and sintered at $875^{\circ}C$, specimen showed density of $4.11g/cm^3$, ${\varepsilon}_r$ of 40.1, $Q{\cdot}f_0$ of 4,869 GHz, and TCF of $-5.9ppm/^{\circ}C$. With 15 weight % of Zn-B-O glass and sintered at $875^{\circ}C$, specimen showed density of $4.14g/cm^3$, ${\varepsilon}_r$ of 40.4, $Q{\cdot}f_0$ of 7,059 GHz, and TCF of $-0.92ppm/^{\circ}C$.

• Journal of Conservation Science
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• v.25 no.4
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• pp.465-471
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• 2009

In this study, the substitution fumigation gases (15% Ethylene Oxide + 85% HFC 134a, 20% Ethylene Oxide + 80% $CO_2$, 99% Sulfuryl Fluoride + 1% Inert Gas) were applied on the metal, pigment, fabric and paper specimen. The result of the fumigation treatment with 15% Ethylene Oxide + 85% HFC 134a (200g/$m^3$, 48hours) is the color changes (${\Delta}E$) of 1st and 2nd Cu specimens showed significant difference as 3.40, 4.17. On the other hand, other specimens except for Cu showed less than 3.0 in chrominance values. The result with 20% Ethylene Oxide + 80% $CO_2$ (150g/$m^3$, 48hours) is that the color changes (${\Delta}E$) of 1st and 2nd specimens were overall less than 3.0 so that color differences were subtle and hardly recognized with naked eyes. So it is proved that the fumigation treatment with Ethylene Oxide 20% + $CO_2$ 80% is relatively stable on materials in this study. In the case of 99% Sulfuryl Fluoride + 1% Inert Gas (50g/$m^3$, 48hours), the color difference of Lead red ($PbO_4$) of pigment was more than 3.0 that was compared with contrast specimens. But chrominance values in the other specimens were less than 3.0 on average.

• Food Science and Preservation
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• v.7 no.4
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• pp.395-402
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• 2000

To enlarge application field of electrolyzed acid-water(EAW) on food industry, the changes of EAW properties by storage conditions and heating were investigatet. It was showed that storing EAW in closed container is mon effective to keep up the oxidation-reduction potentials(ORP), hyperchloride content and pH than stored in opened ones. ORP of EAW stored in closed container could be kept mon than 1 month as 1,150 mV levels. Ruing heating from 2$0^{\circ}C$ to 95$^{\circ}C$, ORP was increased to 1,150 mV levels at 95$^{\circ}C$ after gradual decrease to 5$0^{\circ}C$. Tyrosinase activity was decreased approximately to 26%~35% in EAW having a 950 mV~1,140 mV ORP. Also it was confirmed that EAW has anti-browning effect as sliced apple and potato, and their juices treated with EAW had conspicous difference in their $\Delta$E value. 12 kinds of pesticides such as aldrine, capful diazinon, diedrin, $\alpha$-endosulfan $\beta$-endosulfan, endosulfan sulfate, endrin, $\alpha$-BHC, o,p'-DDT, procymidone, PCNB added in EAW were recovered from ND~73.6% comparing to ones added in distilled water. The recovered amounts of pesticides, procymidone and diazinon in lettuce after soaking in EAW were 1.12 ppm and ND, compared with those of amounts soaked in distilled water were 3.67 ppm and 3.05 ppm respectively. So, it seems that EAW has potentials to promote the degradation of pesticides.

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.108-113
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• 1999

In this study, CT specimens were prepared from ASTM A516 Gr. 65 which was used for pressure vessel plates for moderate and lower temperature service. Fatigue crack growth test was carried out in the environment of low temperature of $10^{circ}C, -10^{circ}C, -30${circ}C\;and\;-50^{circ}C$ and in the range of stress ratio of R=0.05 and 0.3 by means of opening mode displacement. Based on these test results, the characteristics from temperature and stress ration were shown as follows. 1) As the stress ratio, R increased da/dN and ${Delta}K$ of 2nd stage gradually decreased. And as R decreased, the effect of temperature became greater and greater. 2) As the temperature descended, da/dN decreased on a certain ${Delta}K$, and ${Delta}K$ did in a same da/dN. And the stress ratio, R exerted greater influence at the lower temperature. 3) The fatigue crack growth constant, m increased at $10^{circ}C$ and $-10^{circ}C$, snd decreased at $-30^{circ}C$ and $-50^{circ}C$ following the increment of stress ratio R. And m increased along with the reduction of temperature greatly decreased at $-30^{circ}C$ to come close to two(2).

• Progress in Superconductivity and Cryogenics
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• v.13 no.1
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• pp.1-5
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• 2011

[ $CeO_2$ ]has been widely used for single buffer layer of coated conductor because of superior chemical and structural compatibility with $ReBa_2Cu_3O_{7-{\delta}}$(Re=Y, Nd, Sm, Gd, Dy, Ho, etc.). But, the surface of $CeO_2$ layer showed cracks because of the large difference in thermal expansion coefficient between metal substrate and deposited $CeO_2$ layer, when thickness of $CeO_2$ layer exceeds 100 nm on the biaxially textured Ni-3%W substrate. The deposition rate has been limited to be less than 6 $\AA$/sec in order to get a good epitaxy. In this research, we deposited $CeO_2$ single buffer layers on biaxially textured Ni-3%W substrate with 2-step process such as thin nucleation layer(>10 nm) with low deposition rate(3 $\AA$/sec) and thick homo epitaxial layer(>240 nm) with high deposition rate(30 $\AA$/sec). Effect of deposition temperature on degree of texture development was tested. Thick homo epitaxial $CeO_2$ layer with good texture without crack was obtained at $600^{\circ}C$, which has ${\Delta}{\phi}$ value of $6.2^{\circ}$, ${\Delta}{\omega}$ value of $4.3^{\circ}$ and average surface roughness(Ra) of 7.2 nm within $10{\mu}m{\times}10{\mu}m$ area. This result shows the possibility of preparing advanced Ni substrate with simplified architecture of single $CeO_2$ layer for low cost coated conductor.

• Journal of Fashion Business
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• v.16 no.1
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• pp.16-25
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• 2012

As the test results for surface color, dyeing durability, antibiosis of cotton fabrics and silk fabrics dyed with Agastache rugosa extract, the following conclusions were obtained. The surface color of all the dyed fabrics was confirmed mostly as a GY system. As the result of chrominance(${\Delta}E_{ab}$) measurement, in the case of cotton fabrics the dyed fabrics treated with $Al_2(SO_4)_3$ mordant showed the highest value and in the case of silk fabrics the non-mordant dyed fabrics showed the highest value. The dyeing durability of test fabrics dyed with Agastache rugosa extract are as follows. As the test results of colorfastness to laundry for cotton dyed fabrics, the discoloration degree showed 1st-2nd grade and the contamination degree showed 4th-5th grade. As the test result of colorfastness to dry cleaning for silk dyed fabrics, the contamination degree showed from 1st to 3rd-4th grade. As the test results of colorfastness to acid artificial perspiration, the discoloration degree showed from 1st to 3rd-4th grade and the contamination degree showed from 3rd to 4th-5th grade. As the test results of colorfastness to alkaline artificial perspiration, the discoloration degree showed from 1st to 4th grade and the contamination degree showed from 3rd to 4th-5th grade. The colorfastness to sunlight showed from 1st to 2nd grade. The colorfastness to rubbing showed from 3rd to 4th-5th grade in dry process and from 2nd-3rd to 4th-5th grade in wet process. As the test results of antibiosis, the decrease rate of germs to virus Klebsiella pneumoniae and Staphylococcus aureus showed at least more than 99% after the wash of 10 times. As the test results of antifungal activity to mycete Trichophyton mentagrophytes and Aspergillus niger, the both cotton and silk dyed fabrics didn't gain the significant antifungal effect.