• Title/Summary/Keyword: Rate of Substitution

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The Effects of Active Labor Market Policy on Unemployment (적극적노동시장정책이 실업에 미치는 영향)

  • Chai, Goo-Mook
    • Korean Journal of Social Welfare
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    • v.63 no.3
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    • pp.187-211
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    • 2011
  • This study examines the effects of active labor market policy on unemployment by pooled cross-section time series analysis utilizing panel data of 18 OECD countries, and seeks implications for improvements of the Korean active labor market policy. The results of the analysis are summarized as follows. First, active labor market policy negatively affects unemployment rates. Second, vacational training program among three major active labor market programs has a negative effect on unemployment rates. Third, employment service program and employment subsidy program have partially negative effects on unemployment rates. The implications for the Korean active labor market policy are as follows. First, it is necessary to expand and systematize active labor market policies. Second, vocational training programs should be systematized and professionalized according to labor demand. Third, employment subsidy programs need to be planned and carried out under the condition of minimizing a substitution effect, a displacement effect and a deadweight loss effect. Fourth, employment service programs need to be developed and carried out under the consideration of not only the reduction of unemployment rates but also the prevention of re-unemployment, mitigation of income inequality and improvement of productivity.

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Kinetics and Mechanism of the Pyridinolysis of Aryl Ethyl Chlorothiophosphates in Acetonitrile

  • Adhikary, Keshab Kumar;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.11
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    • pp.3947-3951
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    • 2011
  • The nucleophilic substitution reactions of Y-aryl ethyl chlorothiophosphates with X-pyridines are studied kinetically in acetonitrile at $55.0^{\circ}C$. The Hammett and Bronsted plots for substituent X variations in the nucleophiles exhibit biphasic concave upwards with a break point at X = 3-Me. The substituents of X = 4-CN and 4-Ac show great positive deviations from both the Hammett and Bronsted plots. The Hammett plots for substituent Y variations in the substrates exhibit biphasic concave upwards with a minimum point at Y = H. The obtained values of the cross-interaction constants (${\rho}_{XY}$) are all in spite of the biphasic free energy correlations for both substituent X and Y variations, since the ${\rho}_X$values with both the strongly and weakly basic pyridines are almost constant. A stepwise mechanism with a rate-limiting leaving group departure from the intermediate is proposed where the distance between X and Y does not vary from the intermediate to the second transition state. A frontside attack is proposed with the strongly basic pyridines based on the considerably great magnitudes of ${\rho}_X$ and ${\beta}_X$ values and a backside attack is proposed with the weakly basic pyridines based on the relatively small magnitudes of ${\rho}_X$ and ${\beta}_X$. The positive deviations of the two strong ${\pi}$-acceptor parasubstituents, X = 4-Ac and 4-CN, from both the Hammett and Bronsted plots are rationalized by the great extents of bond formation and breaking.

A Study on Autocontrolled SBR for Biological Nutrient Removal with External Carbon Sources (외부탄소원 주입시 영양염류의 생물학적 제거를 위한 자동제어 SBR 공정에 관한 연구)

  • Lee, Byung-hun;Kang, Seong-jae;Lim, Sung-il;Yoo, Pyung-jong
    • Journal of Korean Society on Water Environment
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    • v.18 no.4
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    • pp.371-377
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    • 2002
  • The purpose of this study is to develop effective operating process in order to achieve more suitable conditions of Anoxic-Oxic-Anoxic-Stripper(AOAS) SBR through real-time control. To improve the removal efficiency, glucose, methanol and synthetic food waste acid fermentant were added as an external carbon source, In the case of glucose and synthetic food waste acid fermentant, TN, TP were removed to average 86.9%, 73.0% respectively. Methanol was removed to average 64.6%, 55.4% respectively. The synthetic food waste acid fermentant proved to be the most efficient and allowed for the substitution of an external carbon source. The removal rate of $COD_{Cr}$, was approximately 90% at all cases. The results of the study that a correlation between ORP (Oxidation-Reduction Potential), pH and DO and nitrification or denitrification when an external carbon source is added and when it isn't was showed that ${\Delta}ORP$ is suitable parameter. ORP reacted properly to denitrification (${\Delta}ORP<-10$) and nitrification (${\Delta}ORP<0$). The use of real-time control saved anywhere between 61 and 67 minutes at the anoxic(1) stage and 26 to 52 minutes at the oxic(1) stage. When the time saved from the anoxic(1) and oxic(1) was added to the anoxic(2) stage for the removal efficiency of TN and TP increased from 0.7 to 13.9% and 12 to 35 % respectively.

Study on the Isomerization Reaction of Tetrahydrodicyclopentadiene, Tetrahydrodi(methylcyclopentadiene) Using Heteropolyacid Catalyst (헤테로폴리산 촉매를 이용한 Tetrahydrodicyclopentadiene 및 Tetrahydrodi(methylcyclopentadiene)의 이성화반응 연구)

  • Jeong, Byung Hun;Han, Jeong Sik;Kim, Seong Bo;Kang, Cheol Han;Lee, Bum Jae
    • Applied Chemistry for Engineering
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    • v.18 no.1
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    • pp.36-40
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    • 2007
  • The study on the isomerization reaction of endo-tetrahydrodicyclopentadiene and endo-tetrahydrodi(methylcyclopentadiene) using heteropolyacid catalyst was carried out. Exo compound was prepared from endo compound through isomerization reaction. To improve the problem of aluminum chloride as an isomerization catalyst, application of heteropolyacid was attempted. In use of Keggin type heteropolyacid, catalytic activity was extremely high at cesium substitution instead of 2.5 hydrogen atoms of $H_3PW_{12}O_{40}$. Using the cesium substituted heteropolyacid, isomerization reaction rate was faster than aluminum chloride and the effect of reaction temperature and times on reactivities were compared in isomerization of tetrahydrodicyclopentadiene and tetrahydrodi(methylcyclopentadiene).

Improvement of Production and Secretion of Heterologous \alpha-Amylase from Saccharomyces cerevisiae. (외래 알파아밀라제의 Saccharomyces cerevisiae에서의 생산과 분비효율의 증진)

  • Choi, Sung-Ho;Kim, Geun
    • Microbiology and Biotechnology Letters
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    • v.31 no.1
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    • pp.36-41
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    • 2003
  • In order to increase the production and secretion rate of mouse salivary $\alpha$-amylase from Saccharomyces cerevisiae, various experiments were attempted. A plasmid pCNNinv (AMY) was constructed by the substitution of ADCl promoter and native signal sequence of mouse salivary $\alpha$-amylase cDNA gene with PRBI promoter and yeast invertase leader sequence, which resulted in 25% increase in the production of $\alpha$-amylase in the culture medium. The respiratory deficient transformant carrying pCNNinv (AMY) were obtained by treating yeast cells with ethidium bromide, and the $\alpha$-amylase activities in the culture brothes of the respiratory-deficient transformants were 5-8 times higher than that of parental wild type strain. $\alpha$-Amylase activity was also increased 3 times when the 0.015% (w/v) of 2-mercaptoethanol was added to the culture medium.

The Effects of Substitution Rate of Incinerated Sewage Sludge Ash on the Concrete Materials (건설재료로서 하수슬러지 소각재 적정 대체율 도출에 관한 연구)

  • Kim, Chun ho;Kim, Nam wook
    • Resources Recycling
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    • v.25 no.1
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    • pp.10-15
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    • 2016
  • In recent years, in terms of environmental protection and efficient use of the land, efficient utilization of byproducts and wastes generated in industrial areas are emerging. In this study, for the effective utilization of using ever increasing amount of utilizing sewage sludge incineration ash to increase sewage sludge, it is evaluated the use of as an construction material. After making concrete specimens, it is evaluated compressive strength, carbonation and environmental resistance. From the experimental results, compared with concrete without sewage sludge it is obtained satisfactory results for compressive strength and carbonation and results of the leaching test also satisfies the standard value. So, it is sufficient possibility using of concrete aggregate and the replacement rates is judged to be about 10%.

Effect of Cabbage Powder on Baking Properties of White Breads (양배추 분말 첨가가 제빵 적성에 미치는 영향)

  • Lee, Seon-Ho
    • Food Science and Preservation
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    • v.17 no.5
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    • pp.674-680
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    • 2010
  • This study was carried out to investigate quality characteristics of white breads with cabbage powder(CP) (0, 2.5, 5.0, 7.5 and 10.0%). L-value was significantly decreased by addition of CP, but a and b-values were increased(p<0.05). The degree of pH of dough and bread weight increased with increasing CP concentration, while bread volume, specific volume, and baking loss rate became reduced. The hardness of the breads added with CP was higher than that of the control group. Also, In sensory analysis, the breads with CP showed generally low scores in color, flavor, taste, texture and overall acceptability compared with the control. Taken together, the 2.5%, 5.0% treatment showed similar results with the control group, as compared to other treatments. Addition of CP influenced the color, bread volume and other rheological properties, which is disadvantageous for the quality of white bread. However, compared with the control group, up to 5% CP substitution for flour didn't show significant defferences in sensory test.

Application of turanose as a cryoprotectant for the improvement of Baker's yeast storability (빵효모 저장성 향상을 위한 동결보호제로서의 투라노스 활용 연구)

  • Bae, Go-Eun;Choi, Seong-Won;Lee, Byung-Hoo;Yoo, Sang-Ho
    • Korean Journal of Food Science and Technology
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    • v.54 no.2
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    • pp.224-227
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    • 2022
  • In this study, the protective effects of turanose on Saccharomyces cerevisiae (Baker's yeast) were examined during the freeze-drying process to evaluate the feasibility of utilizing turanose as a novel cryoprotectant. The survival rate of the Baker's yeast cells improved substantially with a cryoprotective medium containing turanose in a substitution-dependent manner. In accordance with these survival rates, the yeast cell surfaces became smoother as the turanose content increased. Turanose with skim milk maintained the viability of the Baker's yeast, which improved substantially upon storage at -20℃. Thus, it is thought that turanose will exhibit excellent preservation effects during the distribution of Baker's yeast. Finally, these results suggest that turanose has the potential to be used as a novel cryoprotectant against various microorganisms.

Synthesis of Cr-doped Pyrochlore-type Pigments and Coloring in Glazes (Cr-doped Pyrochlore계 안료의 합성 및 유약에서의 발색)

  • Eo, Hye-Jin;Lee, Byung-Ha
    • Journal of the Korean Ceramic Society
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    • v.48 no.4
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    • pp.298-302
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    • 2011
  • This study developed a pigment by doping Cr to Pyrochlore-type stannate crystals and investigated the chromogenic relationship in a glaze. Crystal phases of the pigment according to firing temperatures were analyzed by XRD, and the doping relationship was analyzed by Raman Spectroscopy. Color and reflection rate of the pigment were measured by UV-vis Spectrophotometer. Consequently, stannate characteristic band appeared at 307, 408, 505 and $755cm^{-1}$ until 0.1 mole substitution of $Cr_2O_3$. However, as amount of $Cr_2O_3$ increased, the stannate characteristic peak was decreased and shift happened at the left hand side due to Cr-dope. In composition of 0.12~0.14 mole substituted, the unreacted $Cr_2O_3$ stannate characteristic peak, which was not engaged, was shown. This result shows the maximum limit of solid solution was 0.1 mole $Cr_2O_3$. The color of the glaze, which was produced by adding 6 wt% of $Y_2Sn_{1.94}Cr_{0.06}O_7$ pigment in a lime or a lime-magnesia glaze and fired the mixture at $1260^{\circ}C$, was grayish pink with $L^*$ 70.29, $a^*$ 5.68 and $b^*$ 6.27. It showed gray with $L^*$ 68.82, $a^*$ 3.07and $b^*$ 8.13 for $Y_2Sn_{1.9}Cr_{0.1}O_7$.

The Quality Characteristics of Par-Baked Morning Buns made with Cereals Powder (곡류로 제조한 파베이크 모닝빵의 품질 특성)

  • Kim, Hyun-Ah;Song, Chung-Rak;Kim, Yong-Sik
    • Culinary science and hospitality research
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    • v.20 no.6
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    • pp.102-114
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    • 2014
  • The purpose of this study was to promote the consumption of rice by substitution in the process of making par-baked morning buns made with cereal powder in dietary fiber (Brown rice, Barley, Oat, goami 2) and strong flour. Strong flour had the highest fermentation rate for 75 min fermentation period. The volume index of the strong flour morning buns was the highest. The hardness of the strong flour morning buns was measured by a texture analyzer, GR4 respectively. The L-values of strong flour morning buns were higher than those of the Goami powder morning buns. In the sensory evaluation the overall preference was the highest in strong flour morning buns. Among the cereal powder morning buns, the GR4 was the most preferred.