• Journal of the Korean Society of Tobacco Science
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• v.26 no.2 s.52
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• pp.85-92
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• 2004

This study was conducted to investigate the relationship between weather factors during the growing season and chemical components of burley tobacco. Chemical components used in this study was from 'Farm Leaf Tobacco Test' conducted at KT&G Central Research Institute from 1987 through 2002. Data of weather factors during growing season(April to July) were collected in 6 districts measured at Korea Meteorological Adminstration(KMA). Total nitrogen content was increased from 1987 through 2002. Year to year variation of rainfall was the largest, followed by that of sunshine hour. Month to month variation of rainfall also was the largest, followed by that of mean daily air temperature. A negative correlation was found between rainfall and sunshine hour. Relative humidity(R.H.) was correlated positively with rainfall, whereas negatively with sunshine hour. The negative correlations were found between nicotine content and rainfall(in June, May$\~$June, June$\~$July, May$\~$July and average), and R.H.(in June, May$\~$June, June$\~$July, May$\~$July and average), respectively. The negative correlations were found between crude ash content and rainfall(in June and May$\~$June), and R.H.(in June, May$\~$June, June$\~$July and May$\~$July), respectively. Ether extraction content was correlated positively with mean daily air temperature(in July, June $\~$July and May$\~$July) and with sunshine hour(in July, June$\~$July and May$\~$July), but negatively with rainfall(average) and with R.H.(in April, July, June$\~$July, April$\~$June, May­July and average), respectively. Chloride content was correlated positively with sunshine hour(in May, April$\~$May, May$\~$June, April$\~$June, May$\~$July and average), but negatively with rainfall(in June, May$\~$June, June$\~$July, April$\~$June, May$\~$July and average).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.309-313
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• 2018

In this study, we prepared Li-K-Cd alloy, which meets the requirement of eutectic ratio of Li:K, to maintain the operating temperature of the drawdown process at $500^{\circ}C$ and to achieve the reuse of LiCl-KCl molten salt. The prepared Li-K-Cd alloys were added to LiCl-KCl salt bearing U and Nd at $500^{\circ}C$ to investigate the removal of $UCl_3$ in the salt. The reduction of $UCl_3$ in the salt was examined by measuring the OCP value of salt and analyzing the salt composition by ICP-OES. Reduction was also visually confirmed by change of salt color from dark purple to white. The experimental results reveal that the prepared Li-K-Cd alloy has reductive extractability for $UCl_3$ in salt. By improving the preparation method, the Li-K-Cd alloy can be applied to the drawdown process.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.679-684
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• 1997

The major constituents in spent FCC catalysts are Si, Al, Fe, Ti, alkali metals and some others. The spent catalyst is also composed small amounts of rare metals such as Ce, Nd, Ni and V. The selective adsorption and concentration of Ce and Nd from the leaching solution of spent FCC catalysts with sulfuric acid($0.25mol/dm^3$) were carried out by the column method with a chelate resin having a functional group of aminophosphoric acid type. Ce and Nd were separated from eluate liquor containing Al, Nd and V by the precipitation process with oxalic acid. Vanadium is purified from chloride ion coexistance by solvent extraction, employing tri-n-octyl phosphine oxide as extractant with Al in the raffinate solution. Rare metals with the purity of 99 percent were obtained from the spent FCC catalyst.

• Journal of Environmental Health Sciences
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• v.29 no.4
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• pp.27-34
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• 2003

Bisphenol A is used in the manufacture of epoxy, polycarbonate, and corrosion-resistant unsaturated polyester-styrene resins required for food packaging materials in industrial processing. Some reports indicated the possibility of harmful effects on rats. In this study was used a method for the determination of bisphenol A in blood according to the OSHA High Performance Liquid Chromatography (HPLC) guideline. The method involved blood extraction using methylene chloride. And it was evaluated developmental and teratogenic effects in pregnant rats and second generation. The results obtained were as follows. There was a significant increase in the body weights and treated groups F1 female in liver, spleen, kidney, but according to dose-response. F1 female rat's relative body weight and absolute body weight are not different. There was a significant increase liver, spleen, kidney organ weight and reproductive organ weight epididymis, prostate gland in F1 male rats. There was a proestrous in pregnant rat, group 200 $\mu\textrm{g}$/kg, 2000 $\mu\textrm{g}$/kg, 20,000 $\mu\textrm{g}$/kg. The effect on rat treated with bisphenol A decrease organ weight and reproductive organ weight. Identification and quantitation were performed with using HPLC C18 column and using at retention time 5.5 min. The results of the detection of bisphenol A were at 20,000 $\mu\textrm{g}$/kg in average 1 $\mu\textrm{g}$/ml, 200 $\mu\textrm{g}$/kg average in 0.9 $\mu\textrm{g}$/ml blood samples. From those results, it could be concluded that the effects of pregnant rat and second generation(F1) by bisphenol A treatment during lactational period were estrogenic and bisphenol A was remained in serum at low level.

• Nutritional Sciences
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• v.9 no.3
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• pp.159-166
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• 2006

This study was performed to investigate antioxidative and anti-aging action of extracts from Sancho (Zanthoxylum schinifolium) leaves. Two extracts were obtained by 80% methanol extraction followed by subsequent fractionation with methylene chloride (MC) and n-butanol (B) and fed at one or three levels to rats on normal level (5%) of fat (control) and high fat(20%) in diets. Male Sprague-Dawley rats weighing about 100 g were divided into ten groups such as control diet group(C), control diet+0.50%B group (CB), control diet+0.50%MC group (CMC), high-fat diet group (HF), high-fat diet+0.25%B group (HBL), high-fat diet+0.50%B group (HBM), high-fat diet+0.75%B group (HBH), high-fat diet+0.25%MC group (HMCL), high-fat diet+0.50%MC group (HMCM) and high-fat diet+ 0.75%MC group (HMCH) and fed each diet for four weeks. The effects of the extracts on antioxidant enzyme activities and indices of lipid peroxidation and aging were seen only in high fat diet groups. Hepatic superoxide dismutase and aryleaterase activities were not changed by Sancho extracts. But glutathione peroxidase, catalase and paraxonase activities were significantly restored by both MC and B at the level of 0.75% lipid peroxide which was increased by high fat diet was significantly reduced by B and MC at the level of 0.25% and over. Lipofuscin fluorescence and cabonyl value were increased by high fat diet were reduced by B and MC at the level of 0.5% and over. It is concluded that the Sancho extracts can be utilized as functional ingredients of health foods for reducing oxidative stress.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.188-191
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• 2003

Sing]e-well-push-pull tests were developed for use in assessing the feasibility of in-situ aerobic cometabolism of chlorinated aliphatic hydrocarbons (CAHs). The series includes Transport tests, Biostimulation tests, and Activity tests. Transport tests are conducted to evaluate the mobility of solutes used in subsequent tests. These included bromide or chloride (conservative tracers), propane (growth substrate), ethylene, propylene (CAH surrogates), dissolved oxygen (electron acceptor) and nitrate (a minor nutrient). Tests were conducted at an experimental well field of Oregon State University. At this site, extraction phase breakthrough curves for all solutes were similar, indicating apparent conservative transport of the dissolved gases and nitrate prior to biostimulation. Biostimulation tests were conducted to stimulate propane-utilizing activity of indigenous microorganisms and consisted of sequential injections of site groundwater containing dissolved propane and oxygen. Biostimulation was detected by the increase in rates of propane and oxygen utilization after each injection. Activity tests were conducted to quantify rates of substrate utilization and to confirm that CAH-transforming activity had been stimulated. In particular, the transformation of injected CAH surrogates ethylene and propylene to the cometabolic byproducts ethylene oxide and propylene oxide provided evidence that activity of the monooxygenase enzyme system, responsible for aerobic cometabolic transformations of CAHs had been stimulated. Estimated zero-order transformation rates decreased in the order propane > ethylene > propylene. The series of push-pu3l tests developed and field tested in this study should prove useful for conducting rapid, low-cost feasibility assessments for in situ aerobic cometabolism of CAHs.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.66-74
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• 1992

A method for the multiresidual simultaneous analysis of 11 thiocarbamates was studied using HPLC. Thiocarbamate in Chinese cabbage was analyzed in the order of extraction, partition, and cleanup in their optimum condition. Acetone was chosen as an extracting solvent. As a partitioning solvent, the mixture of 50% methylene chloride and petroleum ether containing extremely small water content showed good recoveries of thiocarbamate from the water layer. Partition efficiency was affected by pH of the water layer; it remained almost constant under the acidic and neutral condition while decreasing under the basic condition. The comparison done in cleanup step showed that the column chromatographic method is superior to the treatment of coagulating reagent. As an absorbent, the mixture of charcoal, magnesia, and celite with the ratio of 1 : 2 : 4 gave better recoveries and also effectively removed chlorophyll. Over the total procedure, the average recoveries for thiocarbamates in Chinese cabbage were 91% at about 2 ppm fortification level within the relative standard deviation of 8%, and the minimum detection limit (MDL) was 2.2${\sim}$9.3 ng.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.537-546
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• 1986

In the previous paper(Kim et al, 1986), the alkaline proteinase from the pyloric caeca of mackerel was shown relatively strong activity in the alkaline pH range. Therefore purification of the enzyme has been undertaken to identify the proteolytic enzyme and three alkaline proteinases were isolated by ammonium sulfate fractionation, DEAE-Sephadex A-50 column chromatography and Sephadex G-100 gel filtration. One percent sodium chloride solution was the most effective for the extraction of alkaline proteinase from the pyloric caeca of mackerel. Three alkaline proteinases temporarily designated Enz. A, B and C were isolated from the pyloric caeca of mackerel, and identified to be homogeneous with electrophoresis. The specific activity of the purified Enz. A, B and C was increased to 34, 53 and 37-fold over the crude enzyme solution, respectively. Yield of them was 1.6, 2.1 and $1.5\%$, respectively, and a combined yield was $5.2\%$.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.1-9
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• 1962

Bench-scale horizontal cation-permeable membrane cells were constructed to study the effect of cell dimensions on the efficiency of electrolytic reduction of uranyl sulphate solutions flowing continuously over a mercury cathode. Current efficiencies were determined for various cells having length-to-width ratios of 10/1 to 40/1, and for catholyte solutions containing from 20 to 100g $U_3O_8/l$ in sulphuric acid. Optimum current density and solution flowrate were determined under these conditions. The effects of the nitrate and chloride ions were briefly examined.

• Journal of the Korean Chemical Society
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• v.18 no.2
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• pp.126-131
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• 1974

Trioctylamine-and tricaprylylmethylammonium chloride-tungstate salts have been prepared by solvent extraction from the sodium tungstate solution of various acidities(pH = 2, 4, 6). The molecular weights of the amine-tungstate salts thus obtained could be cryoscopically measured in benzene by means of a home-built Wheatstone bridge utilizing thermistor with sensitivity of 1/$4000^{\circ}C$. The cryoscopic data along with the results of chemical analysis and infrared spectra of the salts indicate that the amine-tungstates prepared at pH = 2 and 4 are all metatungstate whereas the salt obtained at pH = 6 is an unknown form quite different from the expected paratungstate.R = 0.14. By hydrogen bonding a guanidyl nitrogen of a sulfaguanidine molecule is linked to the sulfonyl oxygens of the other molecules indirectly through two different water molecules. The role of water molecule is both a .
nor and an acceptor in hydrogen-bonding formation and these hydrogen bonds are tetrahedrally o？ented. The hydrogen-bonding networks form infinite molecular layers parallel to (001) plane.