• Journal of the Korean Chemical Society
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• v.40 no.10
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• pp.663-669
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• 1996

The rate constants for the nucleophilic addition reactions of thioglycolic acid to vinylsulfilimine(VSI) derivatives(p-OCH3, H, p-Cl and p-Br) were determined by an ultraviolet spectrophotometric method, and rate equations which can be applied over a wide pH range were obtained. On the basis of rate equation, general base catalysis and substituent effect, a plausible addition reaction mechanism was proposed: Below pH 3.0, the reaction was proceeded via the addition of neutral molecule to carbon-carbon double bond after protonation at the nitrogen atom of the sulfilimine, and in the pH range of 3.0 to 9.0, the neutral molecule and its anion attacked to carbon-carbon double bond competitively. Above pH 9.0, sulfide anion added to the double bond (Michael type addition).

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.19-25
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• 1990

A study was undertaken to examine the effect of the addition of dietary fiber on quality attributes of cakes during 12-days storage period at $21^{\circ}C$. Moisture content, degree of gelatinization and hardness determinations were carried out. Addition of dietary fiber increased water holding capacity and decreased hardness and staling rate. Crumb color and sensory quality of cakes with and without dietary fiber was not significantly different.

• Journal of Animal Environmental Science
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• v.6 no.3
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• pp.141-151
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• 2000

Over-grown seaweeds in Donghae(east sea of Korea peninsula) may impedes ocean environment, however, they can be a good nutrient resources for poultry feeds if they are utilized properly. In this study, seaweeds powder were tested for laying hens\` ration to investigate the effects on egg production rate, egg quality and calcium phosphorus excretion. One hundred 65wks-old brown layers were fed for 5 weeks alotted with seaweeds powder addition to experimental diet by 0(control), 0.5, 1.0 and 2.0%, respectively, and obtained following results; 1. Seaweeds proved a mid-protein low-energy feed resources with planty of K, Na, Ca, Mg, Sr and Fe. 2. Seaweeds addition by 0.5% and 1.0% improved egg production rate and egg-mass output markedly(p<0.05) than control. Seaweeds addition did not alter cholesterol level of yolk and yolk index, however egg shell thickness showed increasing trend by increasing seaweeds addition level. 3. Protein absorption and digestibility in seaweed addition treatments were significantly higher(p<0.05) than control group and protein contents of excreta in 0.5% and 1.0% treatments were reduced(p<0.05), which suggests effective protein metabolism for egg production. Increasing seaweeds addition reduces Ca and P contents in rectum and excreta, suggesting Ca and P utilization improvement in laying hens and lessening soil pollution. 4. In conclusion, seaweeds addition in layers' diet by 1.0% level improves egg-mass production and might be egg quality by increasing metabolism of protein, calcium and phosphorus.

• Journal of environmental and Sanitary engineering
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• v.12 no.2
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• pp.75-81
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• 1997

The study was investigated with denitrification of wastewater containing nitrate using upflow anaerobic sludge blanket process. Contents of this study were the determination of nitrate removal efficiency by various hydrogen donor addition, relationship between HRT, nitrate loading rate and growth constant of microorganism in case or various hydrogen donor addition etc. Results from this study were summurized as follows. In case of adding methanol, ethanol, sodium acetate as hydrogen donor, treatability of wastewater contained 200mg/l as nitrate was about 91%. But in addition of ethanol, sodium acetate in wastewater contained 40mg/l as nitrate, nitrate removal efficiency was 80%. While the treatment of nitrate showed the yield coefficient of microorganisms(Y) as 234.8, 234.35, and 247.68 g/VSS/g nitrate, respectively, showed specific growth rate(K) as 0.885, 0.934 and 0.917 respectively.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.3
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• pp.35-41
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• 2019

In this study, the fire resistance performance of polymer cement mortars which are used as a representative repair material for section restoration, is evaluated and residual bond strength is measured by considering unity with concrete. According to the evaluation of fire resistance performance of re-emulsification type polymer cement mortars, residual compressive strength was drastically decreased according to heating temperatures with an increase of polymer addition rate, and this seems to be attributable to the application of polymer film. In addition, an explosion phenomenon occurred frequently with an increase of addition rate, so this should be considered when selecting repair materials and processing.

• Korean Journal of Animal Reproduction
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• v.16 no.2
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• pp.125-131
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• 1992

This study was carried out to investigate the effects of concentration and equilibration time of cryoprotective agents on the survival rate of slowly and ultrarapidly frozen porcine embryos. The porcine embryos following dehydration by cryoprotective agents and a various concentration of sucrose were directly plunged into liquid nitrogen and thawed in 38$^{\circ}C$ water bath. Survival rate was defined as development rat to the morula and blastocyst stage after in vitro culture or by FDA test. The results are summarized as follows : 1. The survival rates of porcine embryos after ultrarapid frozen-thawing in the freezing medium of 0.25M sucrose added 2.0, 2.5, 3.0, 3.5, or 4.0M glycerol was 65.3, 61.8, 64.3, 59.4 or 39.4%, respectively. Addition of 0.25M sucrose into the freezing medium containing 2.0M glycerol showed higher survival rate than those of 2.5~4.0M glycerol. 2. The survival rates of porcine embryos after ultraradpid frozen-thawing in the freezing medium of 0.25M sucroese added 2.0, 2.5, 3.0, 3.5 or 4.0M DMSO was 65.6, 67.6, 68.6, 60.6 or 23.6%, respectively. However, addition of 0.25M sucrose into the freezing medium containing 3.0M DMSO showed higher survival rate than those of 2.0, 2.5, 3.5 or 4.0M DMSO. 3. The survival rates of porcine embryos after ultrapid frozen-thawing in the freezing medium of 0.25M sucrose added 2.0, 2.5, 3.0, 3.5 or 4.0M propanediol was 63.2, 60.3, 62.1, 52.3 or 24.3%, respectively. Addition of 0.25M sucroese into the freezing medium containing 2.0M propanediol showed higher survival rate than those of 2.5~4.0M glycerol. 4. The survival rates of porcine embryos after ultrarapid frozen-thawing the freezing medium of 2.0M glycerol added 0.10, 0.25, 0.50 or 0.75M sucrose was 61.8, 70.8, 67.6 or 52.2%, respectively. Addition of 2.0M glycerol into the freezing medium containing 0.25M sucreose showed higher survival rate than that those of 0.10, 0.50 or 0.75M sucrose. 5. The higher suvival rate of porcine embryos were attained at short period of equilibration time 92.5~5min.) in the freezing medium added 0.25M sucreose and 3.0M compared to those of 10 or 20min. equilibration time in the same condition.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.3
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• pp.9-14
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• 2004

In this study, Si anisotropic etching characteristics of tetramethylammonium hydroxide (TMAH)/ ammonium persulfate(AP)/isopropyl alcohol(IPA) solutions were investigated to realize the optimum structure of a diaphragm for the piezoresistive pressure sensor application. Due to its low toxicity and its high compatibility with the CMOS processing, TMAH was used as Si anisotropic etchants. The variations of Si etch rate on the etching temperature, TMAH concentration, and etching time were obtained. With increasing the etching temperature and decreasing TMAH concentrations, the Si etch rate is increased while a significant non-unifonnity exists on the etched surface because of formation of hillocks on the (100) surface. The addition of IPA to TMAH solution leads to smoother etched surfaces but, makes the Si etch rate lower. However, with the addition of AP to TMAH solution, the Si etch rate is increased and an improvement in flatness on the etching front is observed. The Si etch rate is also maximized with increasing the number of addition of AP to TMAH solution per one hour. The Si square membranes of 20${\mu}{\textrm}{m}$ thickness and l00-400${\mu}{\textrm}{m}$ one-side length were fabricated successfully by applying optimum Si etching conditions of TMAH/AP solutions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.361-365
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• 2003

Planar Inductively Coupled Plasma (PICP) etching of InGaP was performed in $BCl_3,\;BCl_3/Ar\;and\;BCl_3/Ne$ plasmas as a function of ICP source power ($0\;{\sim}\;500\;W$), RIE chuck power ($0\;{\sim}\;150\;W$), chamber pressure ($5\;{\sim}\;15\;mTorr$) and gas composition of $BCl_3/Ar\;and\;BCl_3/Ne$. Total gas flow was fixed at 20 sccm (standard cubic centimeter per minute). Increase of ICP source power and RIE chuck power raised etch rate of InGaP, while that of chamber pressure reduced etch rate. We also found that some addition of Ar and Ne in $BCl_3$ plasma improved etch rate of InGaP. InGaP etch rate was varied from $1580\;{\AA}/min$ with pure $BC_3\;to\;2800\;{\AA}/min$ and $4700\;{\AA}/min$ with 25 % Ar and Ne addition, respectively. Other process conditions were fixed at 300 W ICP source power, 100 W RIE chuck power and 7.5 mTorr chamber pressure. SEM (scanning electron microscopy) and AFM (atomic force microscopy) data showed vertical side wall and smooth surface of InGaP at the same condition. Proper addition of noble gases Ar and Ne (less than about 50 %) in $BCl_3$ inductively coupled plasma have resulted in not only increase of etch rate but also minimum preferential loss and smooth surface morphology by ion-assisted effect.

• Journal of the Korean Chemical Society
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• v.35 no.3
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• pp.268-274
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• 1991

The rate constants for the nucleophilic addition reactions of thiourea to ${\beta}$-nitrostyrene derivatives(p-H, p-Cl, p-CH$_3$, p-OCH$_3$, p-NO$_2$) were determined by UV spectrophotometer and rate equations which can be applied over a wide pH ranges were obtained. On the basis of substituent effect, general base catalysis and rate equations, a reaction mechanism was proposed and revealed quantitively. Above pH 9.00, sulfide anion adds to the double bond(Michael type addition) and between pH 7.00 and 9.00, the neutral molecules and its anions add to the double bond competitively. Below pH 7.00, the addition reaction to double bond is initiated by the addition of neutral thiourea molecule.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.201-201
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• 2003

It has been well known that Ni-MILC TFTs are acceptable for operation of LCD devices but still decrease of annealing temperature is desirable for the future devices like LCD on the plastic substrate. In this work, Cu was added to Ni-MILC in an attempt to lower the annealing temperature and enhance the MILC rate. It has been found that even small amount of Cu addition enhances the MlLC rate considerably. Also well One MILC can be distinguished from island type, which cannot be observed in pure Ni-MILC. Poly TFTs were fabricated with Cu/Ni-MILC and the effects of copper addition on the electrical properties were carefully investigated.