• Bulletin of the Korean Chemical Society
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• v.6 no.1
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• pp.15-19
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• 1985

(Z)-12-Tetradecen-1-yl acetate (1), (E)-12-tetradecen-1-yl acetate (2) and tetradecan-1-yl acetate (3), the active components of the sex pheromone of the Asian Corn Borer moth were synthesized by two different methods, one from acetylene and 11-bromo-1-undecanol THP ether by acetylenic route, the other from 12-acetoxy-1-dodecanal and ethylidenetriphenylphosphonium ylide by Wittig route.

• Journal of the Optical Society of Korea
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• v.14 no.1
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• pp.14-21
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• 2010

Fiber ring laser based intra-cavity absorption spectroscopic sensor has great potential for high sensitivity gas detection. Using the rate equations and propagation equations, we investigated theoretically factors that affect the sensitivity of such fiber ring laser sensors and determined the optimal design parameters and conditions for significant enhancement of the system sensitivity. Experiments have been conducted to determine the sensitivity enhancement performance. The results showed a factor of 25 ~ 30 in sensitivity enhancement in the experimental system, agreeing well with the theoretical expectations. Experiments on acetylene detection have also been carried out and the results showed that the ring cavity significantly increases the signal absorption and that high sensitivity can be obtained for gas detection.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.3
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• pp.286-293
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• 1983

The glucose application remarkably increased the heterotrophic acetylene reducing activities during one month incubation. The amount of the increases varied between the soils. Application of rice straw brought about the significant increases during incubation time. Compost contained the largest amount of available-N among the C-sources, and thereby brought the smallest increase in all soils. The cumulative fixed nitrogen with application of rice straw at 30 days incubation in the three experimented soils were highest in Hwadong clay soil, i.e, $2.2mg^N/100g$, intermediate in Ratchaburi soil $0.85mg^N$, and least in Konosu soil $0.80mg^N/100g$. On the other hand, nitrogen fixing heterotrophic, bacteria, such as Clostridia, aerobes and anaerobes, were remarkably increased by application of rice straw while Azotobacter and Beijerinkia were not. The cumulative fixed nitrogen was more pronounced in the clay soil than in the coarse loamy soil. More pronounced nitrogen fixing activities in light condition(heterotrophic + photosynthetic) than that in dark(heterotrophic) condition have been observed both in the coarse loamy and clay soils. The nitrogen fixing ability of photosynthetic microbes in paddy soil is probably higher in coarse loamy soil than in clay soil.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.131-136
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• 2013

This study was conducted to select rhizobia from hairy vetch (Vicia villosa Roth) with nodulation and excellent nitrogen-fixing ability. Hairy vetch root was collected from 7 of cultivation region of all over the country, rhizobia were isolated from the root nodules. Isolates were re-inoculated into a hairy vetch separately and studied nodulation and nitrogen-fixing ability. As a result, total of 52 Rhizobium isolates were isolated from the hairy vetch root nodules, among these, 16 isolates were Rhizobium which show good growth at more than 0.5% NaCl concentration. These 16 isolates were re-inoculated separately, 8 weeks after, good root nodule formation was observed from Rhizobium sp. RH1, RH3, RH81, RH82, RH84, and RH93 strain treated samples. Six isolates were positive for nitrogen fixing ability, the highest acetylene reduction activity was shown by Rhizobium sp. RH84. Results suggest that the Rhizobium sp. RH84 could be used as the possibility of its application as a green manure crop of hairy vetches in nonuniform salt distribution reclaimed land.

• Resources Recycling
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• v.19 no.3
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• pp.33-44
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• 2010

In this study, the possibility of utilizing carbide lime waste, obtained from the generation of acetylene process, as a alkali activator of blast furnace slag cement was investigated. The physical and chemical analysis of the carbide lime waste was studied and three types lime waste in order to investigate behaviour as alkali activator were used. Lime wastes were added 0, 10, 20 and 30 wt.% in blast furnace slag and blast furnace slag containing lime waste were added 0, 10, 30 and 50 wt.% in OPC. As a result of analysis of hydration properties, in the case of calcium hydroxide rehydrated after heat treatment at $800^{\circ}C$, it was higher hydration rate than other specimens. For the results of compressive strength test, when lime waste passed 325 mesh sieve and rehydrated calcium hydroxide were used, it was higher compressive strength than OPC from hydration 7days. At OPC50 wt.%-BFS45 wt.%-AA5 wt.% system using lime waste of 325 mesh under, the highest compressive strength appeared.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.1
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• pp.1-7
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• 1978

Laboratory and pot experiment were carried out to find the symbiotic nitrogen fixing activities and the yield of dry matter on the several selected wild soybean plant. 1. Very high acetylene reducing(nitrogen fixing)activities were observed in isolated strains of Rhinchosis volubilies Lour. (924 nmole), Desmodium oldhami Oliver (844 nmole) and Glycine soja s. et z. (271 nmole/test tube/hr) while Rhizobium japonicum was only 0.6 nmole/test tube/hr. 2. On the serological reaction, eight isolated Rhizobium strains were sufficiently different to distinguish from the Rhizobium japonicum. 3. On the pot experiment with Glycine soja s. et z., A. Number of total nodules were higher in NPK+rice straw+Ca+Mo than in NoPK. However, little differences were observed in mumber of effective nodules. B. Yield of dry matter was increased with increasing of nitrogen content in plants. C. Estimated amount of fixed nitrogen in plant by an individual nodule was higher in NoPK than in NPK+rice straw+Ca+Mo.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.4
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• pp.434-442
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• 1988

This study has been made to investigate the influences of organic matter on the soil composition, nitrogen fixing organism, soil enzyme activity and nitrogen fixing activity in the paddy rice rhizosphere when rice and barley straw were applied. The results are summarized as follows: 1. The pH in the submerged soil was increased from ear formation stage to harvesting. 2. In the rhizosphere, $Fe^{{+}{+}}$ content was decreased according to the growing stage, while increased in the nonrhizosphere. 3. In the initial stage, rhizosphere was higher than nonrhizosphere but in the late stage nonrhizosphere was higher than rhizosphere on the $NH_4-N$ content. 4. In the submerged soil, rhizosphere was higher than nonrhizosphere, on the concentration of glucose and pentose. 5. Changes of the number of nitrogen fixing organism in whole soil was not high. 6. Generally, rhizosphere was higher than nonrhizosphere on the soil enzyme activity such as phosphatase, ${\beta}$-glucosidase, and protease. 7. Acetylene-reducing activity was the highest in the tillering stage, and rhizosphere, Samgang (high-yielding variety) were higher than nonrhizosphere. Dongjin (general variety) respectively. 8. In the submerged soil applied barley straw, acetylene-reducing activity was slightly higher than rice straw in the initial stage.

• Applied Biological Chemistry
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• v.19 no.1
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• pp.1-23
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• 1976

The female moths of Lepidoptera comprising over 1,000,000 described species possess long-chain unsaturated alcohols or esters as the typical structure of potential sex attractants. In this experiment, various stereoisomers of $C_{16}-unsaturated$ acetates were synthesized for potential sex attractants; e.g., $CH_3(CH_2)_mCH=CH(CH_2)_nOR$ (m=0-12, n=1-13, R=H and $-COCH_3$). Seventeen acetates were spectrometrically examined so that the data would provide a ready catalog of gas chromatography and mass spectrometric data for comparison with natural insect sex attractants. Exclusively cis and trans isomers were obtained by the catalytic and chemical reduction methods, respectively. Commercially available $CH_3(CH_2)_mBr,\;CH_3(CH_2)_mC{\equiv}CH,\;HC{\equiv}C(CH_2)_nOH\;and\;HO(CH_2)_n\;OH$ were used for the synthetic starting material. 1-Alkynes, $CH_3(CH_2)_m\;C{\equiv}CH$ exceeding nine methylene groups did not condense with alkyl dihalides. The yield of coupling products was gradually decreased with increasing the molecular weight of diols. In the coupling reaction of $BrCH_2CH_2$ OTHP with acetylene gas, the tetrahydropyranyl ether of bromohydrin produced undesirable elimination product. In this experiment, it seems that p-toluenesulfonic acid is greatly favoured hydrolyzing agent over dilute sulfuric acid in the hydrolysis of the tetrahydropyranyl ether of long-chain alkynols.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.1
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• pp.16-22
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• 1993

Ladino clover stolen growing in grazed sward transplanted in 1/5,000a Wagner pot with two rows and were grown in green house with 12h lighting. Fifty days after transplanting the first cutting was made, the secound and 3rd cutting was made 20 days after each harvest. Treatment were nitrogen fertilization level of 2.5, 5.0 and 7.5 kg N/10a. Nitrogen was top dressed after transplanting and each cutting. Growing point, above and under ground DM yield, nitrogen fixation, crude protein of stolon, root and change of acetylene reduction activity after cutting were investigated. Result are as follows. 1. Growing point, DM production were heighst in 5 kg N at the first and 2nd harvest while 2.5 kg at 3rd cutting. Plants with 7.5 kg N/10a were dead at 3rd harvest. There were significant differences in growing point between treatment. 2 Nitrogen fixation of ladino clover were the heightest in 2.5 kg N pot at 1st cutting and as cutting and N fertilization were contiuned nitrogen fixation activity was lowered. 3. Leaf have more crude protein than that of stolen and root while plant crude protein increased by 2nd cutting as plant got more nitrogen fertilizer and again decreased in 3rd cutting. 4. Acetylene reduction activity were lowest at 3 week and recovered normal level at 5 week after cutting, also DM root was same trend.

• Korean Journal of Optics and Photonics
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• v.19 no.1
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• pp.54-59
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• 2008

We report on the measurements of absorption spectra from acetylene ($^{12}C_2H_2$) and hydrogen cyanide ($H^{13}C^{14}N$) for wavelength reference in the C-band (conventional band) region using a supercontinuum optical source generated from a mode-locked $Cr^{4+}$:YAG laser. The center wavelength of the mode-locked $Cr^{4+}$:YAG laser was 1510 nm and the pulse duration was 75 fs at 100 MHz repetition rate. The supercontinuum source achieved a flatness of ${\pm}5dB$ over a wavelength range of more than 400 nm, using a 20 m long photonic crystal fiber. The measured absorption spectra from acetylene ($^{12}C_2H_2$) and hydrogen cyanide ($H^{13}C^{14}N$) had more than 50 lines and were analyzed for wavelength standardization.