• Title/Summary/Keyword: Dry unit weight

Search Result 308, Processing Time 0.048 seconds

Effect of Nitrogen and Phosphorus Fertilization on the Growth and Root Respiration of Paddy Rice (질소 및 인산시용이 수도의 근호흡 및 생육에 미치는 영향)

  • Young-Soo Han;Je-Cheon Chae;Jong-Hoon Lee;Yoon-Jin Oh
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.24 no.4
    • /
    • pp.1-11
    • /
    • 1979
  • Increased nitrogen fertilization increased root respiration and top dry weight of rice plant, and increased phosphorus fertilization increased root respiration only with the same amount of nitrogen applied. The effect of phosphorus on root respiration under low growth temperature was not significant and the large application of phosphorus alone decreased root respiration greatly. Root respiration per unit root weight correlated highly with top dry weight and nutrient uptake.

  • PDF

Relationship of Nitrate Reductase Activity to Leaf Yield, Protein, Sugar and Physiological Attributes in Mulberry (Morus alba L.)

  • Ghosh, M.K.;Das, B.K.;Das, C.;Mishra, A.K.;Mukherjee, P.K.;Urs, S.Raje
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.8 no.1
    • /
    • pp.67-71
    • /
    • 2004
  • Ten improved mulberry varieties (Vl, C1730, C2016, C2017, Anantha, RFS-175, Thallaghatapura, Vishala, S1 and S1635) were evaluated through enzyme assay and estimation of soluble protein content followed by regression analysis, grown under irrigated conditions in the alluvial soils of Gangetic plains of West Bengal in India for five successive crops in a year, The nitrate reductase (EC No. 1.6.6.1) activity (NRA, $\mu$mol N $O_2$- $h^{-1}$ $g^{-1}$ fr, wt.), total soluble protein (mg $g^{-1}$ fr, wt.) was estimated which showed to vary significantly in the tested varieties. In addition to these, the other parameters like unit leaf fresh and dry weight (g), moisture %, unit leaf area ($\textrm{cm}^2$), specific leaf weight (g c $m^{-2}$ ), total soluble sugar (mg $g^{-1}$ fr, wt.), leaf yield/plant (kg), shoot yield/plant (kg) and net photosynthetic rate (NPR, $\mu$$m^{2}$ $s^{-1}$ ) were also studied which showed to vary significantly in tested varieties. Among them, S1635, haying higher NRA (13.25 $\mu$㏖ N $O_2$- $h^{-l}$ $g^{-1}$ fr, wt.), total soluble protein (39.63mg $g^{-1}$ fr, wt.), NPR(16.66 $\mu$$m^{-2}$ $s^{-1}$ ), total soluble sugar (48.44 mg $g^{-1}$ fr. wt.), leaf yield/plant (0.689 kg) and shoot yield/plant (1.135 kg) showed its superiority over other tested varieties. Regression and correlation coefficients were analysed, and a strong positive correlation was found between NRA & total soluble protein, NRA & NPR, NRA & total soluble sugar, NRA af unit leaf weight, NRA & specific leaf weight, NRA & leaf yield/plant, NRA & shoot yield/plant, NPR & leaf yield and NPR & specific leaf weight.t.

The Physical and Mechanical Properties of the Weathered Shale Soils in Hwasun Area (화순 지역 셰일 풍화토의 물리적.역학적 특성에 관한 연구)

  • 김종렬;박정훈;김해경;강권수
    • The Journal of Engineering Geology
    • /
    • v.14 no.2
    • /
    • pp.199-210
    • /
    • 2004
  • In this study, the physical and mechanical properties of the weathered shale soils distributed in the Hwasun area have been measured in the laboratory. The physical and mechanical properties of the weathered shale soils in the study area as follows: the specific gravity is 2.66 to 2.68, the liquid limit is 36.39 to 36.92(%), the plastic limit is 18.53 to 19.48(%), the plasticity index is 17.44 to 17.86 and soil classification is CL. The maximum dry unit weight and optimum moisture content as calculated by compaction test is 22.5 to 23% and 1.58 to $1.61t/\textrm{m}^3$, respectively. The result of direct shear testing show that cohesion in saturated and unsaturated conditions increases according to the increase of dry unit weight. Internal friction angle in an unsaturated condition increases with an increase of dry unit weight, but in a saturated condition, it increases after decreasing. When compares with engineering characteristics of tile weathered shale soils in the Daegu area (Kim et al., 1995), specific gravity is found to be similar, but the liquid and plastic limit of soil samples in this study area is slightly higher than those of soil samples in the Daegu area.

Model Testing on the Behavior of Laterally Loaded Pile in NC Clay Soils (정규압밀 점토 지반에서 매입말뚝의 수평거동에 관한 모형 실험 연구)

  • Kim, Byeong-Tak;Lee, Sang-Ung;Kim, Yeong-Su
    • Geotechnical Engineering
    • /
    • v.14 no.5
    • /
    • pp.39-52
    • /
    • 1998
  • The pupose of the present paper is to estimate the effects of constraint condition of pile head, ground condition(dry unit weight. $\gamma_4$) and embedded pile lengths on the behavior of single pile which is embedded in normally consolidated clay. BBperiment functions can be quantified to these effects obtained from the results of model teats. The ground of model tests is normally consolidated( NC ) clay under three kinds of effective vertical stress. The results of the model tests using the steel pile of two different embedded pile length and of free-head and fired-head show that the lateral load-deflection relationship is to be elasto plastic behavior below $\gamma_d/\gamma_{dmax}$: 0.84 and that the reduction of lateral load of beyond maximum lateral load($Q_{max}$) at each model test is significantly time-dependent. In this study, it is shown that the displacement relationship can be fitted to exponential function of time by model best results. The effect of ground conditions on the ultimate and yield lateral load is fitted to exponential function including the ratio of dry unit weight to maximum dry unit weight. When tests by results are compared with those from Broms and Budhu et at., the predicted results are over-estimated about 27-87 ayo. In effectivity of constraint condition of pile head on the lateral load-deflection response, the $Q_{fixed}/Q_{gree}-y/D$ relationship is highly non-linear and fitted to parabolic function.

  • PDF

Adsorption of $\textrm{Pb}_{2+}$ in the components of bacterial cell membrane

  • Kim, Mal-Nam
    • Journal of Microbiology
    • /
    • v.33 no.4
    • /
    • pp.278-282
    • /
    • 1995
  • S. epidermidis cell was fractionated into cell wall, cell membrane and cytoplasm. The cell membrane adsorbed the most abundant $\textrm{Pb}_{2+}$ per unit dry weight of the three fractions tested. Adsorption behavior of $\textrm{Pb}_{2+}$ in lipid and protein, which are the main components of the cell membrane, indicated that phosphatidylethanolamine and phosphatidylinositol having phosphoryl group and gangliosides containing carboxyl groups adsorbed much more $\textrm{Pb}_{2+}$ than triglycerides lacking any chargeable functional groups. Protein purified from cell membrane adsorbed larger amount of $\textrm{Pb}_{2+}$ than total native cell membrane or cell membrane lipid.

  • PDF

Changes in the composition of artificial cariogenic biofilms over time (인공 우식 유발성 biofilm 구성성분의 시간 흐름에 따른 변화)

  • Oh, Chul;Pandit, Santosh;Jeon, Jae-Gyu
    • Journal of Korean Academy of Oral Health
    • /
    • v.43 no.3
    • /
    • pp.118-123
    • /
    • 2019
  • Objectives: The purpose of this study was to investigate changes in the composition of artificial cariogenic biofilms using a Streptococcus mutans biofilm model over a period of time. Methods: We analyzed the dry weight, colony forming unit (CFU) number, extracellular polysaccharide (EPS) biovolume, and acid production rate of S. mutans biofilms formed on saliva-coated hydroxyapatite discs after 26 h, 50 h, 74 h, 98 h, 171 h, and 195 h. In addition, we performed a laser scanning confocal fluorescence microscopy to determine the bacterial volume, EPS biovolume, and biofilm thickness. We calculated the biofilm density using dry weight and EPS biovolume. Results: Over a period of time, there was no change in the CFU number and acid production rate of S. mutans biofilms, but there was an increase in the dry weight and EPS biovolume of S. mutans biofilms. The bacterial volume, EPS biovolume, and biofilm thickness only increased in the 50-h-old biofilm; however, no change was observed in 50-195-h-old biofilms. In addition, an increase in the biofilm density was observed over time. Conclusions: These results suggest that the acid production ability of cariogenic biofilms does not change, but the biofilm density increases over time. However, due to scientific information, further research needs to be conducted in the field of dentistry to get further insights on the progression of cariogenic biofilms over time.

Studies on the Competition-Density Effect of Some Higher Plants (수종 식물의 밀도-경쟁효과에 관한 연구)

  • 진희성
    • Journal of Plant Biology
    • /
    • v.15 no.2
    • /
    • pp.7-19
    • /
    • 1972
  • The studies of density effect or the effect of population density on plant growth have been done on basis of dry matter production with Raphanus acanthiformis var. simoodaeguen, Brassica campestris var. Pekinensis f. namsounsokoombecheu, Oryza sativa f. kimmajae and O. sativa f. mangyeng grown in the various spacing. 1. In the early period of plant growth in dry weight was not different each other among varying densities, but as time advanced the plant grown vast space grew sufficiently compared with those of narrow one. 2. Iogarithmic relation between the growth of plant (W) and the density (P), log W-log P in the material plants, were approximated by two straight lines, one was horizontal line and another inclined: the former showed non-competition density and the latter competition density addition to these the point interlinking both lines were implied of the optimum density per unit land area at certain growth period. 3. The values of relatvie growth rate (RGR) and net assimilation rate (NAR) were decreased as increase in the density, while those of leaf area ratio (LAR) were rather increased in the same condition, with minor exception. From these results and relation between the productive structure and due to lack of the recieved light intensity owing to the mutal shading among the plants.

  • PDF

Characteristic of Matter Allocation of Calystegia soldanella under Water Stress (갯메꽃의 수분스트레스에 대한 물질분배 특성)

  • Park, Yong Mok
    • Journal of Environmental Science International
    • /
    • v.22 no.2
    • /
    • pp.187-193
    • /
    • 2013
  • Dry matter allocation characteristics of Calystegia soldanella, grown in pots, was analysed to assess its plasticity in response to water-stressed conditions. As water was withheld leaf water potential between the two watering treatments was similar during the first 6 days, followed by a rapid decrease in water-stressed plants. The minimum leaf water potential was -1.50 MPa on day 15 and the maximum leaf water potential was about -0.5 MPa on day 0 in water-stressed plants. In well-watered plants leaf water potential was maintained almost consistently throughout the experiment. There was no significant difference in plant dry weight between the two watering treatments for 9 days after the start of experiment and that was remarkably increased thereafter, compared with that remained without any increase in water-stressed plants. In dry mass partitioning, however, the water-stressed plants showed a great plasticity, showing that there were 1.81, 1.35 and 0.81 times increase in root, stem and leaf, respectively. Dry mass partitioning in well-watered plants varied from 2% to 5%. The difference of dry mass partitioning between the two watering treatments was reflected in leaf mass per unit area (LMA) and root/shoot (R/S) ratio. LMA in water-stressed plants was lower than that in well-watered plants, while R/S ratio in water-stressed plants was higher in well-watered plants. This means that the water-stressed plants reduced its leaf area and increased dry mass partitioning into root and stem during the progress of soil drying. These results indicate that Calystegia soldanella inhabiting in sand dune cope with water stress with high plasticity which can adjust its dry mass partitioning according to soil water conditions.

Silage Yield of Korean Local Maize Lines(MET) with Many Tillers and Ears (다수다얼성 재래종 옥수수 계통의 청예수량)

  • Lee, Hee-Bong;Choe, Bong-Ho;Cho, Young-Hwan
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.30 no.3
    • /
    • pp.277-286
    • /
    • 1985
  • From a series of studies conducted on the local maize lines at the Agr. College of the Chungnam National Univ., a few maize lines with many tillers and ears per plant were identified and tentatively named as MET. The purpose of the study was to evaluate the MET lines, which were selfed for five generations, for silage purpose under the different plant densities. A hybrid, Suwon #19 and a synthetic variety, Puyo #3${\times}$#2, were included for comparison. Plant height at harvesting times showed no significant varietal differences. However, the MET lines were very slow in early plant growth compared to the hybrid or synthetic variety, probably due to inbreeding depression of the MET lines. Total fresh weight at the harvesting times was highest in the MET 1 line. The MET 1 line was about 2,000 kgr. per 10a. higher than the hybrid at the harvesting time. The highest fresh weight was obtained when grown under the plant density of 60 ${\times}$ 20cm. Total dry weight per unit area showed the same tendency as the fresh weight. Total dry weight of MET 1 line was about 2.4 tons per 10a., which was about 10% higher than the hybrid, Suwon #19. As the fresh weight, the total dry weight was also highest in the plant density of 60 ${\times}$ 20cm. The grain yield per 10 are of MET 1 was comparable to the grain yield of the hybrid, especially in the low plant density, 60 ${\times}$ 40cm. The average number of effective tillers of MET lines were 4.5, while the mean tiller number of the hybrid or synthetic variety were none. However, the lodging was one of the problem for growing MET lines. The 100 kernel weight of MET lines was about 9 gr., while the 100 kernel weight of the hybrid or synthetic variety was about 30 grm.

  • PDF

Compaction Characteristics of Organic Mixture Soils with Surfactants (계면활성제를 사용한 유기물 혼합토의 다짐 특성)

  • Kwon, Ho-Jin;Park, Pan-Young
    • Journal of the Korean Geotechnical Society
    • /
    • v.27 no.3
    • /
    • pp.19-26
    • /
    • 2011
  • Compaction tests have been performed to investigate the compaction characteristics of sands and clays with organic mixture. Weathered granite soil, kaolinite, and granulated carbon were used as the alternatives of sand, clay, and organics, respectively. The soapy water which is a kind of surfactant solutions was also used as water substitute to see the engineering properties changes of each soil. As seen when water was used, the optimum moisture contents increased and the maximum dry unit weight decreased for the soil with surfactants as the percentage of the organic contents increased. Surfactants slightly improved the compaction efficiency at low compactive energy level for the weathered granite soil with organics. As the organic contents increased for clays with surfactants, the optimum moisture contents decreased and the maximum dry unit weight increased. Surfactants slightly improved the compaction efficiency of clays with organics at all levels of compaction energy.