• 제목/요약/키워드: Growth control

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식물생장조절물질이 산뽕나무 종자의 발아 및 유묘생장에 미치는 영향 (Effects of Plant Growth Regulators on Seed Germination and Seedling Growth of Mountain Mulberry Seeds (Morus bombycis Koidz))

  • 송민정;김경훈;허영진
    • 한국환경복원기술학회지
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    • 제19권1호
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    • pp.101-109
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    • 2016
  • This is the fundamental research on restoring damaged vegetation areas in the vicinity of DMZ using local native plant species. This research is aimed at identifying effective plant growth regulators (PGR) for seed germination and seedling growth of mountain mulberry, and developing effective methods for managing its germination and growth. Mountain mulberry seeds were collected from the regions in the DMZ vicinity, and tests with seven treatments using four PGRs including $GA_3$, kinetin, ABA and NAA, were conducted. The germination rate was calculated in two different ways of both in a growth chamber and in a greenhouse after seven days observation, and the growth characters such as leaf width/length, seedling width/length and fresh/dry weight, have been surveyed in a greenhouse for three months. Although in the growth chamber the highest germination rate was shown at a group with the kinetin treatment, it was not significantly different to that of the control group. Groups with ABA or NAA presented relatively low germination rates. As for the greenhouse test, the germination rates of all groups ranged 20~30% without significant difference each other, the reason of which might be due to low absorption by the effect of a soil drench method used in this study. The entire growth characters with the treatments of $2.15mg{\cdot}L^{-1}$ of kinetin and $10mg{\cdot}L^{-1}$ of $GA_3$ were significantly different to the control. NAA treatment only showed better growth of seedling width compared to the control. Consequently, the most effective PGRs for the germination and growth of mountain mulberry near the DMZ was kinetin. Further research on examining the most effective concentration of them was needed.

R&D Expenditure, International Trade and Economic Growth: Korea's Experience

  • Yi, Myung-Hoon;Mah, Jai-Shin
    • 유통과학연구
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    • 제14권3호
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    • pp.39-44
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    • 2016
  • Purpose - The purpose of this research is to investigate whether Korea's economic growth can be explained by the endogenous growth theory. Specifically, we test whether R&D expenditure has a positive and significant effect on the economic growth. Research design, data, and methodology - We hypothesize that R&D expenditure has a positive effect on the economic growth after adding control variables in the growth equation. Korean annual data from 1963 to 2011 from Science and Technology Annual of the Ministry of Education, Science and Technology, the Bank of Korea, etc. are used. We estimate the growth equation by GMM in addition to OLS. Results - We found that R&D expenditure has a positive and significant effect on the economic growth after adding the ratio of investment to GDP, the ratio of FDI to GDP, the ratio of government expenditure to GDP, inflation and the ratio of trade openness to GDP as control variables in the growth equation. Conclusions - Our results show that Korea's rapid economic growth for the past five decades can be explained by the R&D-based endogenous economic growth theory. Our results suggest that the policy attention of the Korean government be paid to R&D promotion.

열수화법으로 성장시 성장 온도에 따른 ZnO 나노 구조의 표면 형상 변화

  • 배영숙;김동찬;조형균
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
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    • pp.238-238
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    • 2009
  • In this work, we investigated the effect of the Zn complex concentration and growth temperature on the growth of ZnO nanorod by hydrothermal method. The ZnO nanorods were performed at condition of the various Zn complex concentration and growth temperature, 0.02 ~ 0.08 M and 60 ~ 80 $^{\circ}C$, respectably. We found from the SEM results that the diameter and length of ZnO nanorods were with increasing the growth temperature and Zn complex concentration. However, the growth condition in the two parameters wasmore than sensitive compared to Zn complex concentration on increasing the growth rate. From photoluminescence(PL) analysis, the strong band-edge emission for ZnO nanorod grown at 80 $^{\circ}C$ with 0.08 M indicated the fine crystallinity. Therefore, the diameter and length of ZnO nanorods have been able to control through the control of front growth parameters. Also, these ZnO nanorods grown low temperature will be available as building block for transparence flexible device applications.

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자기성장집단 상담이 우울성향 아동의 자아개념과 대인관계에 미치는 효과 (The Effects of the Self-Growth Group Counseling Program on Self -Concept and Interpersonal Relationships of Depressed Children)

  • 오명희
    • 한국초등상담교육학회:학술대회논문집
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    • 한국초등상담교육학회 2004년도 학술대회
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    • pp.119-135
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    • 2004
  • The purpose of this study was to examine the effects of the self-growth group counseling program on the self-concept and the interpersonal relationships of depressed children in elementary school. A total 20 children who were screened by CDI criteria participated in this study, these students were randomly assigned to the experimental group(N=10) and the control group(N=10). The self-growth group counseling programs were implemented for ten week period. The research hypothesis were as follows: 1-1 : The scores on the self-concept measure of the experimental group received the self-growth group counseling program will be higher than the control group. 1-2 : The post-test scores on the self-concept measure of the experimental group received the self-growth group counseling program will be higher than the pre-test scores. 2-1 : The scores on the interpersonal relationships measure of experimental group received the self-growth group counseling program will be higher than the control group. 2-2 : The post-test scores on the interpersonal relationships measure of the experimental group received the self-growth group counseling program will be higher than pre-test scores. 3-1 : The scores on CDI of the experimental group received the self-growth group counseling program will be lower than the control group. 3-2 : The post-test scores on CDI of the experimental group received self-growth group counseling program will be lower than pre-test scores. The results of the study were as follows: First, the scores of the self-concept and the interpersonal relationships measures of the experimental group students appeared to be higher than the control group. However among the self-concept measure, the score of the emotional self showed no statistically significant differences between the groups. Second, within the experimental group, the scores of the self-concept and the interpersonal relationships measures of the post-test appeared to be higher than the pre-test. Third, the scores on CDI measures also showed significant mean differences between the experimental group and the control group, and between the pre- and post-tests. These findings suggested that the self-growth group counseling program interventions were functioned as for improving the self-concept and the interpersonal relationships, and for decreasing the depressed level of children. The implications and limitations of the study were discussed, and the suggestions for further researches were made.

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솔리드 요소를 이용한 적층복합재 구멍의 형상 최적화 (Shape Optimization of Three-Dimensional Cutouts in Laminated Composite Plates Using Solid Element)

  • 한석영;마영준
    • 한국공작기계학회논문집
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    • 제13권4호
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    • pp.16-22
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    • 2004
  • Shape optimization was performed to obtain the precise shape of cutouts including the internal shape of cutouts in laminated composite plates by three dimensional modeling using solid element. The volume control of the growth-strain method was implemented and the distributed parameter chosen as Tsai-Hill fracture index for shape optimization. The volume control of the growth-strain method makes Tsai-Hill failure index at each element uniform in laminated composites under the initial volume. Then shapes optimized by Tsai-Hill failure index were compared with those of the initial shapes for the various load conditions and cutouts. The following conclusions were obtained in this study (1) It was found that growth-strain method was applied efficiently to shape optimization of three dimensional cutouts in a laminated composite plate, (2) The optimal shapes on the various load conditions and cutouts were obtained, (3) The maximum Tsai-Hill failure index was reduced up to 67% when shape optimization was performed under the initial volume by volume control of growth-strain method.

Optimization for Scenedesmus obliquus Cultivation: the Effects of Temperature, Light Intensity and pH on Growth and Biochemical Composition

  • Zhang, Yonggang;Ren, Li;Chu, Huaqiang;Zhou, Xuefei;Yao, Tianming;Zhang, Yalei
    • 한국미생물·생명공학회지
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    • 제47권4호
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    • pp.614-620
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    • 2019
  • Microalgae have been explored as potential host species for biofuel production. Environmental factors affect algal growth and cellular composition. The effects of several key environmental factors, such as temperature, light, and pH of the medium on the growth and biochemical composition of Scenedesmus obliquus were investigated in this study. The highest growth rate of microalgae was observed at an optimal temperature of 25℃, 150 μmol/(m2·s) light intensity, and pH 10.0. The biochemical composition analysis revealed that the carbohydrate content decreased at lower (20℃) or higher temperature (35℃), whereas the protein and lipid contents increase at these temperatures. The fluctuation of light intensity significantly affected the contents of protein, carbohydrate, and lipid. The protein levels varied greatly when the pH of the medium was below 7.0. The carbohydrate and lipid contents significantly increased at pH above 7.0.

증착변수 및 첨가가스에 따른 다이아몬드 박막의 구조적 물성 및 전계방출 특성의 변화 분석 (Characterization of structural and field-emissive properties of diamond films in terms of growth conditions and additive gases)

  • 박재현;이태훈;박창균;서수형;박진석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1571-1573
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    • 2003
  • Diamond films including nanocystalline and graphite phase are grown by microwave plasma chemical vapor deposition using $N_2$ additives and negative substrate bias at growth step. The microstructure of the films is controlled by changing $N_2$ gas ratio and negative bias. Defects and grain boundaries between diamond and graphite are proposed to be crucial factors for forming the conducting path of electron emissions. The effect of growth parameters on the film microstructure are investigated by Raman spectroscopy and scanning electron microscopy(SEM). Electron emission characteristics are also examined in terms of the film growth conditions.

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산수유 유산균 발효액의 모발성장 효과 (The Promoting Effect of Cornus officinalis fermented with Lactobacillus rhamnosus on Hair Growth)

  • 박장순;이재숙
    • 생약학회지
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    • 제42권3호
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    • pp.260-264
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    • 2011
  • The bacterial growth and pH of Cornus officinalis fermented with Lactobacillus rhamnosus during fermentation were evaluated. As the results, the number of the fermentation after fermentation always remained higher than 6 log CFU/mL and the pH of those ranged from 4 to 6. To evaluate the effect of Cornus officinalis fermented with Lactobacillus rhamnosus on hair growth promotion in C57BL/6 mice, Six weeks old male mice were divided into four groups including normal group (saline), negative control group (essence base), positive control group (minoxidil) and experimental group (Cornus officinalis and animal milk fermented with Lactobacillus rhamnosus mixed in negative control). And they were applied topically with test materials for 8 days. Hair regrowth effect in experimental group using gross and histological examination was higher than that in positive control group. Body weight and food intake of four groups didn't show significant difference. These results indicated that the Cornus officinalis fermented with Lactobacillus rhamnosus can be used practically for hair growth or prevention of hair loss.

Shape Control of Gold Nanocrystal: Synthesis of Faceted Gold Nanoparticles and Construction of Morphology Diagram

  • Ahn, Hyo-Yong;Lee, Hye-Eun;Nam, Ki Tae
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.281.1-281.1
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    • 2013
  • Shape control of gold nanocrystal is still one of the most important challenges remaining to achieve geometry dependent properties. Thus far, several strategies have been developed to control the shape of nanoparticles, such as adding capping agents and diverse additives or adjusting the temperature and pH. Here, we used an already established seed-mediated method that allowed us to focus on controlling the growth stage. Cetyltrimethylammonium bromide (CTAB) and ascorbic acid (AA) were used as the ligand and the reducing agent, respectively, without using any additional additives during the growth stage. We investigated how the relative ratio of CTAB and AA concentrations could be a major determinant of nanoparticle shape over a wide concentration range of CTAB and AA. As a result, a morphology diagram was constructed experimentally that covered the growth conditions of rods, cuboctahedra, cubes, and rhombic dodecahedra. The trends in the morphology diagram emphasize the importance of the interplay between CTAB and AA. Furthermore, high-index faceted gold nanocrystal was obtained by two step seeded growth. Already synthesized cubic particles developed into hexoctahedral nanocrystal consisting of 48 identical {321} facets, which indicates that the growth of gold nanocrystal is affected by initial morphology of seed particles. The hexoctahedral gold nanoparticles can be used in catalysis and optical applications which exploiting their unique geometry. Our research can provide useful guidelines for designing various facetted geometries.

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Growth and Physiological Responses of Quercus acutissima Seedling under Drought Stress

  • Lim, Hyemin;Kang, Jun Won;Lee, Solji;Lee, Hyunseok;Lee, Wi Young
    • Plant Breeding and Biotechnology
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    • 제5권4호
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    • pp.363-370
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    • 2017
  • In this study, Quercus acutissima seedlings were subjected to drought for 30 days then analyzed to determine their response to water deficit. The growth phenotype, chlorophyll fluorescence response, fresh weight, dry weight, photosynthetic pigment levels, soluble sugar content, and malondialdehyde (MDA) were measured to evaluate the effects of drought on plant growth and physiology. The growth phenotype was observed by infrared (IR) digital thermal imaging after 30 days of drought treatment. The maximum, average, and minimum temperatures of drought-treated plant leaves were $1-2^{\circ}C$ higher than those of the control. In contrast, the fresh and dry weights of the dehydrated leaves were generally lower than those of the control. There were no significant differences between treatments in terms of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid levels. Nevertheless, for the drought treatment, the $F_v/F_m$ and $F_v/F_o$ ratios (chlorophyll fluorescence response) were lower than those for the control. Therefore, photosynthetic activity was lower in the dehydrated plants than the control. The drought-stressed Q. acutissima S0536 had lower soluble sugar (glucose and fructose) and higher MDA levels than the controls. These findings may explain the early growth and physiological responses of Q. acutissima to dehydration and facilitate the selection of drought-resistant tree families.