• Title, Summary, Keyword: mass propagation

Search Result 418, Processing Time 0.04 seconds

A Study on the Flame Propagation Characteristics for LPG and Gasoline fuels by Using Laser Deflection Method (레이저 굴절법을 이용한 LPG와 가솔린 연료의 화염전파 특성에 관한 연구)

  • Lee, Kihyung;Lee, Changsik;Kang, Kernyong;Kang, Woo
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.24 no.12
    • /
    • pp.1608-1614
    • /
    • 2000
  • For the purpose of obtaining fundamental data which is needed to develope combustion system of LPG engine, we made constant volume chamber and analyzed flame propagation characteristics under different intial temperature, initial pressure and equivalence ratio which affect combustion of LPG. We investigated flame propagation speed of each fuel using laser deflection method and compared with the investigated flame propagation speed of each fuel using laser deflection method and compared with the results of image processing of flame. As a result, the maximum flame propagation speed was found at equivalence ratio 1.0 and 1.1 for LPG and gasoline, respectively. In the lean region, we can see that flame propagation speed of LPG surpasses that of gasoline. On the contrary, flame propagation speed of gasoline surpasses LPG in the rich region. As initial temperature and initial pressure were higher, flame propagation speed was faster. And, as equivalence ratio was larger and initial temperature was higher, combustion duration was shorter and maximum combustion pressure was higher.

Mass Propagation by Stem Cutting in Ligusticum chuangxiong Hort. (토천궁(土川芎)의 줄기삽목에 의한 대양번식(大量繁殖))

  • Yu, Hong-Seob;Bang, Jin-Ki;Kim, Young-Guk;Lee, Bong-Ho
    • Korean Journal of Medicinal Crop Science
    • /
    • v.7 no.3
    • /
    • pp.200-204
    • /
    • 1999
  • Ligusticum chuanxiong has been an important oriental crude drug and cultivated for a long time in Korea. Ligusticum chuanxiong has been vegetatively propagating crop without seed due to its sterility and would be an allodiploid derived from the hybridization of two allied species. Generally, vegetative propagation is more costly per unit propagule than sexual(seedling) propagation. This study was conducted to find out the techniques of mass propagation by stem cutting for reduced seedling cost. When cutted on August 30 with 1st to 2nd internode, its highest rooting percentage was 81 percent. Rhizome yield of plants cutted in 50 percent on September 1 decreased to 9 percent less than control (rhizome propagation). Rooting percentage of rooted cutting plants after field planting on October 25 was the highest being 87 percent. Rhizome yield with planting appeared 127 and 120kg/10a on September 25 and October 25, respectively.

  • PDF

Establishment of Mass Propagation System of Virus-Free Sweetpotato Plants and Conservation

  • Lee, Joon-Seol;Chung, Mi-Nam;Jeong, Byeong-Choon;Ahn, Young-Sup;Kim, Hag-Sin;Park, Jong-Suk;Bang, Jin-Ki
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.52 no.2
    • /
    • pp.220-227
    • /
    • 2007
  • Sweetpotato fields in Korea are highly infected with virus and virus like diseases that greatly diminish both yield and quality as indicated by field observations and laboratory tests. In order to solve this problem, there is an urgent need to produce and mass propagate virus-free planting materials for distribution to the farmers. These experiments were conducted, firstly, to determine the most appropriate culture media, nutrient solution, and cutting intervals to maintain growth and vigor of tissue cultured plantleta as mother plants for propagation in insect-proof greenhouse. And as a labor saving method, the production efficiency of plug trays for rapid propagation of stem cuttings as a source of planting materials was likewise evaluated. Results showed that plants grown in medium B supplied with 0.5 and 1.0 strength of MS nutrients had high growth rate, and 20-day cutting interval was the best. 72-plug tray was better than 128-plug. Secondly, it was to develop a technique for the production of first-generation seed roots using hydroponics cultivation system. The yield of virus-free plants propagated in the non-insect proof and open-field cultivation was 2,402 kg/10a, 6% higher than those in the insect-proof cultivation, and the rate of virus re-infection was 18% higher compared to 3.3% with insect-proof cultivation. Lastly, it was to investigate the growth performance of virus free plants in farmers' field. Differences were existed in the yield depending on the variety used, but virus free plants showed an increase of $6{\sim}24%$ over virus infected plants.

In vitro Plant Propagation: A Review

  • Kumar, Nitish;Reddy, M.P.
    • Journal of Forest and Environmental Science
    • /
    • v.27 no.2
    • /
    • pp.61-72
    • /
    • 2011
  • Micropropagation is an alternative mean of propagation that can be employed in mass multiplication of plants in relatively shorter time. Recent modern techniques of propagation have been developed which could facilitate large scale production of true-to-type plants and for the improvement of the species using genetic engineering techniques in the next century. An overview on the in vitro propagation via meristem culture, regeneration via organogenesis and somatic embryogenesis is presented. The usefulness of the plants in commercial industry as well as propagation techniques, screening for various useful characteristics and the influence of different cultural conditions in the multiplication, rooting and acclimatization phases on the growth of tissue cultured plant discussed.

The influence of initial stress on wave propagation and dynamic elastic coefficients

  • Li, Xibing;Tao, Ming
    • Geomechanics and Engineering
    • /
    • v.8 no.3
    • /
    • pp.377-390
    • /
    • 2015
  • The governing equations of wave propagation in one dimension of elastic continuum materials are investigated by taking the influence of the initial stress into account. After a short review of the theory of elastic wave propagation in a rock mass with an initial stress, results indicate that the initial stress differentially influences P-wave and S-wave propagation. For example, when the initial stress is homogeneous, for the P-wave, the initial stress only affects the magnitude of the elastic coefficients, but for the S-wave, the initial stress not only influences the elastic coefficients but also changes the governing equation of wave propagation. In addition, the P-wave and S-wave velocities were measured for granite samples at a low initial stress state; the results indicate that the seismic velocities increase with the initial stress. The analysis of the previous data of seismic velocities and elastic coefficients in rocks under ultra-high hydrostatic initial stress are also investigated.

Permeability Prediction of Rock Mass Using the Artifical Neural Networks (인공신경 망을 이용한 암반의 투수계수 예측)

  • Lee, In-Mo;Jo, Gye-Chun;Lee, Jeong-Hak
    • Geotechnical Engineering
    • /
    • v.13 no.2
    • /
    • pp.77-90
    • /
    • 1997
  • A resonable and economical method which can predict permeability of rock mass in underground is needed to overcome the uncertainty of groundwater behavior. For this par pose, one prediction method of permeability has been studied. The artificial neural networks model using error back propagation algorithm, . one of the teaching techniques, is utilized for this purpose. In order to verify the applicability of this model, in-situ permeability results are simulated. The simulation results show the potentiality of utilizing the neural networks for effective permeability prediction of rock mass.

  • PDF

Development of Mass Propagation System via Rhizome Culture in Elite Breeding Line C269 of Alstroemeria (근경 배양을 이용한 알스트로메리아 우량 육종계통 C269의 대량증식 체계 개발)

  • Park, Sung-Wha;Lee, Sang-Hyun;Kim, Jong Bo;Jung, Hyo Jin;Wi, Seong-Gon;Han, Tae-Ho
    • FLOWER RESEARCH JOURNAL
    • /
    • v.25 no.4
    • /
    • pp.232-239
    • /
    • 2017
  • An in vitro production system of Alstroemeria C269 was investigated to provide virus-free stock of domestically selected for cultivar registration. Alstroemeria C269 was bred in the ornamental plant science laboratory at Chonnam National University and primarily cultured on MS basal medium. Rhizome tips for rhizome mass propagation were cultured on MS medium supplemented with different concentrations of 6-benzylaminoputin (BAP) and kinetin (KIN). Explants from the medium supplemented with KIN had numerous shoots and densely grew. Therefore, this approach was unsuitable for in vitro rhizome mass propagation due to difficult rhizome splitting. However, explants cultured in medium supplemented with BAP at a concentration below $0.2mg{\cdot}L^{-1}$ were appropriate for in vitro rhizome split propagation. The greatest number of roots was obtained from the medium supplemented with NAA at $0.25mg{\cdot}L^{-1}$. However, abnormal roots were observed in the medium supplemented with N AA. More rootlets and root hair were induced in MS medium than in MS medium supplemented with NAA. In acclimation, plantlets survived more in MS medium than in MS medium supplemented with N AA. Besides, the shoot induction and aboveground growth were better in MS medium than in MS medium supplemented with NAA. Based on these results, the efficient rhizome mass propagation method of Alstroemeria hybrid C269 is 8 weeks of culture in MS medium supplemented with $0.2mg{\cdot}L^{-1}$ BAP, followed by culture in MS medium for around 5 weeks for rooting before acclimation.