• Journal of the Korean Society of Tobacco Science
• /
• v.31 no.2
• /
• pp.69-74
• /
• 2009

Potato Virus Y (PVY), PVY-vein necrosis strain, causes severe damage at growth, yield and leaf quality on flue-cured tobacco in Korea. The development of PVY resistant flue-cured varieties without quality deterioration is therefore urgently desired. The flue-cured tobacco, KF120 (Korea Flue-cured 120), was a male-sterile (ms) $F_1$ hybrid derived from the cross between msKF117 and KF0007-7. msKF117 was developed from the cross of NC82 with N. africana and KF0007-7 was developed from the cross of KF117 with NC82. The agronomic characteristics and disease resistance of KF120 was evaluated during 2006-2007 field performance test. It showed better growth characteristics and yield performance than standard cultivar KF109. It had 2 more leaves per plant, flowered 2 days later than KF109. The yield of cured leaf of KF120 was increased by about 5% compared to KF109. The chemical composition and physical properties of the cured leaf of KF120 were as much acceptable as those of KF109. KF120 showed high resistance to PVY compared to KF109. It showed a similar mode of resistance to bacterial wilt and black shank as was found in KF109.

• Korean Journal of Food Science and Technology
• /
• v.29 no.4
• /
• pp.635-640
• /
• 1997

The oxidative stability of the potato chip prepared with canola oil fortified with antioxidnats was studied to explore the possibility of substituting it for imported frying fats and oils. BHT, BHA, TBHQ and silicone were added to the oil at a level of 0.02% and 10 ppm, respectively. Potato chip samples were prepared in a commercial scale and stored at $25.0{\pm}0.5^{\circ}C$ for 5 months. The oxidative stability of the extracted oils from potato chips during storage was estimated on the basis of some their physico-chemical changes, such as acid values, peroxide values, iodine values, ansidine values, fatty acid composition of the oils. An organoleptic test for the flavor of the samples was also performed. The oxidative stability of the samlpes was estimated on the basis of the changes of the parameter values. The effectiveness of the antioxidants was in the order of canola oil+TBHQ (0.02%)+silicone (10 ppm) > canola oil+TBHQ (0.02%) > canola oil+BHA (0.02%)+silicone (10 ppm) > canola oil+BHT (0.02%)+silicone (10 ppm) > canola oil+BHA (0.02%) > canola oil+BHT (0.02%) > canola oil. The antioxidant effect of canola oil+TBHQ (0.02%)+silicone (10 ppm) was more salient than any other antioxidant used in the potato chip.

• Journal of the Mineralogical Society of Korea
• /
• v.18 no.3 s.45
• /
• pp.147-153
• /
• 2005

Naldrettite, recently discovered in the Mesamax Northwest deposit, Ungava region, northern Quebec, Canada, was reported as a new mineral. In order to confirm whether itis a natural equivalent of synthetic $Pd_2Sb$ phase or not, the pure $Pd_2Sb$ phase has been synthesized and investigated by reflected microscope, electron microprobe analyser, X-ray diffractometer, and micro-indentation hardness tester. Under reflected light synthetic $Pd_2Sb$ Phase is white with a creamy tint in both air and oil and weakly bireflectant. Anisotropism is strong, from brownish gray to greenish blue in air. Micro-indentation hardness test gives VHN100=293(242-322). Composition of the phase is $63.7\~64.3wt.\%\;Pd\;and\; 36.4\~36.8wt.\%$ Sb, and is entirely consistent. The phase, quenched from $500^{\circ}C$, is orthorhobic with space group $Cmc2_1$, and the cell parameters are a=3.366(1), b=17.523(3), c=6.929(2) ${\AA}$. All mineralogical properties of synthetic $Pd_2Sb$ compare very well with those of naldrettite, confirming that naldrettite is the natural analogue of the synthetic $Pd_2Sb$ phase.

• Applied Biological Chemistry
• /
• v.19 no.3
• /
• pp.155-161
• /
• 1976

The say sauce koji where made use of different kinds of seed koji were used to brewing of soysauce. The pure, complex and bacteria contaminated seed koji were used in this experiment, And the euzyme activity, Micrflora, chemical composition and TN-solubility ratio of each soysauce mash during the fermentation periods were measured respectively. The results obtained were as follows. 1. The neutral and alkali protease activity of each soysauce mash were decreassed in the process of fermentation period. In this case the activitities of protease in the bacteria contaminated koji were remarkably decreased. 2. The microflora in one ml of soysauce mash showed the tendency of increase in process of fermentation period. The increase in bacteria contaminated seed koji group was remarkable. 3. The content of total nitrogen, amino-N and ammonia-N in soysauce during the course of fermentation were increase. And alcohol, reducing sugar and pure extract contents in soysauce were also increased in the former stage of fermentation, but in the latter stage of fermentation decreased. 4. Though the content of ammonia-N in bacteria contaminated seed koji group was high, the pH value was low in comparison with the others. 5. Pure seed koji group were shown the most effective in the result of total nitrogen solubility ratio and sensual test, while the bacteria contaminated seed koji group was the worst.

• Applied Biological Chemistry
• /
• v.50 no.2
• /
• pp.87-94
• /
• 2007

A bacterium which has high enzymatic activities such as amylase, cellulase and protease was isolated from Korean traditional soybean food, doenjang. The isolated bacterium was identified to Bacillus subtilis HS25 by the test of morphological and biochemical properties according to Bergey's Manual of Systematic Bacteriology and API 50 CHL kit, and by the 16S rDNA sequence. The isolated B. subtilis HS25 had a potent antibacterial activity against food born causative or pathogenic bacteria. B. subtilis HS25 is endospore forming cell and contained flagella and abundant viscous material at the out layer of cell wall. It was rod type bacterium $(0.5{\sim}0.8{\times}3{\sim}5{\mu}m)$ having biochemical characteristics such as gram staining(+), catalase(+), oxidase(-) and hydrolysis of esculin(+). The optimal medium compositions for production of antibacterial substance in the B. subtilis HS25 were 1% of soluble starch, 0.5% of yeast extract, 0.5% of peptone and 0.05% of MgCl$_2{\cdot}6H_{2}O$. The optimum temperature and pH of the growth of the B. subtilis HS25 was 35$^{\circ}C$ and pH 7.5, respectively. The antibacterial activity was more high in neutral to a little alkaline pH (6.5-10.5) than in acidic pH. The optimal shaking speed to grow and to produce antibacterial substance of the B. subtilis HS25 was 160${\sim}$200 rpm. The optimal culture time for antibacterial activities of the bacterium were shown to be in the range of 12-36 hr.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.3
• /
• pp.173-178
• /
• 2001

This study was performed to know the hypocholesterolemic effect of depolymerized alginate obtained by hydrolysis of alginate through a heating process at $121^{\circ}C$. The changes of total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and phospholipid levels in serum, as well as the atherogenic index were elucidated in rats for 35 days. In order to evaluate single-dose toxicity of HAG-50 in rats via oral routes, induction any mortalities and abnormal signs in clinical finding, body weight, gross findings and histopathological finding, and estimation of $LD_{50}$ were elucidated. Total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and phospholipid levels in the serum significantly decreased and resulted in the decrease of atherogenic index in rats fed diets containing $5\%\;and\;10\%$ HAG-50 (p<0.01). HAG-50 did not induce any mortalities and abnormal signs in clinical findings, body weights, gross findings and histopathological findings in single-dose toxicity test via oral routes of rats, after which it was impossible to estimate $LD_{50}$ values.

• Journal of the Microelectronics and Packaging Society
• /
• v.8 no.3
• /
• pp.55-62
• /
• 2001

With a spread of BGA, CSP and fine pitch devices, the need of flatter surface finish in bare board is becoming more critical in solderability. The electroless Ni/Au plating has a solution of these needs and also has being spread to apply to surface finish for bare board in many electronic goods. But, the electroless Ni/Au plating had several issues such as Ni oxidation and phosphorous contents. Before this study, we studied on the effect of BGA solderability in electroless Ni/Au plating and chose some major factors such as the oxidation property of NiP plating and warpage of board. Firstly, we made test board with various plating conditions and improved the plating property through the improvement of NiP oxidation reducing P content. Also, we minimized the warpage of board with the improvement of inner layer structure and the analysis of warpage. For the evaluation of solderability, we analyzed the warpage of board and the plating property after mounting BGA on the board with optimizing conditions. The solder joint of BGA is investigated by SEM(Scanning Electronic Microscope) and OM(Optical Microscope). The composition of joint is used by EDS(Energy Dispersive Spectroscopy). We analyzed the fracture strength and mode by ball shear teser.

• Journal of the Korean Chemical Society
• /
• v.43 no.4
• /
• pp.438-446
• /
• 1999

The optimum analytical method of aldehydes, ozone by-products, was established by reverse phase liquid chromatography. Six aldehydes including formaldehyde, acetaldehyde, acrolein, propionaldehyde, butylaldehyde and benzaldehyde, and one ketone including acetone were selected as aldehyde test samples through preliminary experiments. Such analytical conditions as the pH of citrate buffer solution, reaction temperature, reaction time, and concentration of DNPH, the component and composition of desorption solvent were optimized. As the result, pH 3.0 of citrate buffer solution, 40$^{\circ}C$ of reaction temperature, 15 minutes of reaction time, and 0.012% of DNPH concentration were chosen as optimum conditions. Aldehydes-DNPH derivatives in water were concentrated on $C_18$ Sep-Pak cartridge and followed by elution of their derivatives fraction with THF/ACN(70/30) mixture, and showed recoveries of the range from 87 to 107%. Separation condition on Nova-Pak $C_18$ column with low pressure gradient elution from ACN/MeOH/water(30/10/60) of an initial condition to 80% ACN of a final condition was found to give a good resolution within 20 minutes of run time. 86% to 103% of recovery for aldehydes using this method was similar to that for aldehyde using EPA Method 554 which is ranged from 84% to 103%.

• Journal of the Korean Data and Information Science Society
• /
• v.26 no.6
• /
• pp.1397-1407
• /
• 2015

Individual phenotype is mostly influenced by genetic factors as well as the effects of environmental factors. Therefore, adjustment of environmental factors are needed in order to see more clearly the effects of genetic factors that we are interested in gene screening study related to Hanwoo's economic trait. The purpose of this study is to propose new statistical model that was adjusted environmental factor and identify adjustment effect in a superior gene marker screening study for producing high quality Hanwoo. First, statistical model including both genetic factor and environmental factor establishes and adjusted value of economic trait find by removing effect of environmental factor such as age, breeding farm. Finally, we identify superior gene marker combination and compare accuracy by applying MDR to data of before and after adjustment. Economic trait is used C18:1, SFA, MUFA, MS, CWT, BFT and SNP marker is used 6 markers of LPL that were identified as more excellent SNP marker than the others among 49 markers through fatty acid composition and economic trait performance test.

• Journal of the Korean Electrochemical Society
• /
• v.1 no.1
• /
• pp.45-51
• /
• 1998

[ $AB_2-type$ ] alloy, one kind of hydrogen storage alloys used as an anode of Ni-MH batteries, has large discharge capacity but has remaining problems regarding initial activation, cycle life and self-discharge. This study investigates the effects of Cr-addition and fluorination after La-addition on $Zr_{0.7}Ti_{0.3}V_{0.4}Mn_{0.4}Ni_{1.2}$, composition $AB_2-type$ alloy. EPMA and SEM surface analysis techniques were used and the crystal structure was characterized by XRD analysis. In addition, electrodes were fabricated out of the alloys and characterized by constant current cycling test, electrochemical impedance spectroscopy and potentiodynamic polarization. Cr-addition was found to be effective to cycle life and self-discharge but ineffective to initial activation due to formation of stable oxide film on surface. Fluorination after La-addition to the alloys improved initial activation remarkably due to formation of highly reactive particles on surface.