• Title/Summary/Keyword: Water uptake

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Assessment of different pretreatments to breakage dormancy and improve the seed germination in Elaeocarpus serratus L. - an underutilized multipurpose fruit tree from South India

  • Raji, R.;Siril, E.A.
    • Forest Science and Technology
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    • v.14 no.4
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    • pp.160-168
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    • 2018
  • The seeds of Elaeocarpus serratus, a tropical underutilized fruit tree are characterized by hard seed coat and consequent poor water uptake and low germination. To improve the regeneration through seeds, various parameters such as viability of seeds, water uptake, and effect of seed mass on germination and pretreatments were performed using a completely randomized design (CRD). Tetrazolium (TZ) test was conducted using fresh, mature seeds revealed $50{\pm}2.56%$ mean viability. Seeds of different weight classes showed similar pattern of water uptake and the saturation level was achieved at 60 hrs of soaking. Seeds belong to weight class 2.6-3.5g were germinated ($12.5{\pm}1.26%$) with $175{\pm}1.75days$ (d) of mean time taken for germination (MTG). Germination capacity of seeds varied significantly among different populations and Varkala population gave $12.5{\pm}1.1%$ germination with $174.6{\pm}2.5d$ MTG. Among various seed treatments, mechanical scarification was superior in germination and significant reduction in MTG ($p{\leq}0.05$). The mechanical scarification by complete removal of seed coat resulted in $49.2{\pm}1.52%$ germination within a short period of time ($9.52{\pm}0.89d$ MTG). However, the complete removal of seed coat without damaging to embryo is a difficult task. An alternate treatment (Mechanical scarification II) by making cracks on nut faces vertically followed by soaking in distilled water for 24 hrs gave $48.4{\pm}1.73%$ germination with significantly reduced MTG ($12.14{\pm}0.56d$) over unsoaked, untreated control ($6.5{\pm}1.84%$ germination and $197.18{\pm}1.79d$ MTG; $p{\leq}0.05$). This treatment (Mechanical scarification II) is therefore recommended for E. serratus seeds as it can adopt easily and can achieve 7 fold increases in germination over control. The recorded germination through mechanical scarification is in tune with realized viability percentage of the seeds.

Uptake of Butachlor by Rice Seedlings and Its Phytotoxic Action to the Physiological Activities (수도묘(水稻苗)의 Butachlor 흡수(吸收) 및 약해발생(藥害發生) 특성(特性)에 관한 생리적(生理的) 연구(硏究))

  • Chung, Bong-Jin;Kwon, Yong-Woong
    • Korean Journal of Weed Science
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    • v.1 no.1
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    • pp.57-68
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    • 1981
  • To clarify the mode of uptake of butachlor (2-chloro-2', 6'-diethyl-N-(butoxymethyl) acetanilide) by rice seedlings, its phytotoxic action to growth and physiological activities, studies were conducted with rice seedlings, at the 6th or 7th leaf-stage, which were treated with nutrient solution containing butachlor 0, 1.8, 3.6, 7.2, 10.8 or 14.4 ppm for 1, 2 or 4 days, in other case, the solutions were thereafter renewed with the untreated nutrient solution for further growth. Uptake of butachlor by rice seedlings increased linearly with increase of its concentration and duration of uptake. Butachlor inhibited root growth more than shoot growth, furthermore, the inhibitory effect on the shoot growth was greater in height than in weight or leafing rate. After 4 day-treatment, the rates of shoot growth in weight were delayed for 4 days. Butachlor inhibited water uptake rapidly and linearly with increase of its external concentration. The reduced uptake of water was followed by slow increase in the stomatal resistance of leaves. Upon completion of butachlor treatment, rate of water uptake was recovered rapidly, but the stomatal resistance with lag in time. Butachlor did not affect the uptake of cation such as ammonium, potassium and calcium, but inhibited substantially uptake of nitrate in proportion to its concentration. Especially, butachlor did not affect synthesis and degradation of nitrate reductase. In addition, butachlor has shown much greater binding to the lipidic substances from rice roots than the proteinous material. The primary mechanism of phytotoxic action of butachlor does not seem to be its effect on the protein synthesis, but great affinity to membranes. The inhibition of water uptake, and its subsequent closure of stomates is thought very important for reduced growth under mild phytotoxicity.

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Nutrient Absorption by Citrus unshiu Marc. Grown in Out-Door Solution Culture (양액재배에서 감귤나무의 무기양분 흡수)

  • Anh, Nguyen Than;Kang, Tae-Woo;Song, Sung-Jun;Park, Won-Pyo;Nong, Nguyen Ngoc;U., Zang-Kual
    • Korean Journal of Soil Science and Fertilizer
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    • v.36 no.4
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    • pp.225-232
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    • 2003
  • Nutrients and water absorption by Citrus unshiu Marc. cv. Miyagawa Wase were examined using spray type of out-door hydroponics system. Three different concentration levels of nutrient solution were treated to citrus trees to examine nutrient uptake. To do so, concentration and the volume change of nutrient solution was measured for each treatment. By weighing the volume of solution and citrus trees, amounts of water uptake and fresh weight increase were observed periodically. Water uptake by trees increased as tree grew and time elapsed, but was lower at high level of nutrient concentration than the rest, due partly to the reduction in hydraulic conductance and to the sustained high salt concentration. Rapid increase in fresh weight and nutrient uptake occurred from May to July and from August to September. The amounts of nutrient uptake were significantly different among nutrient levels: the higher concentration, the greater uptake by citrus tree. The absorbed amounts of $NO_3$, K and Ca were much higher than those of $NH_4$, S, P, Mg, and Fe. Most mineral contents in leaves were proportional to the concentration of supplied nutrient solutions. From the results of nutrient absorption and contents in leaves at different levels of nutrient solutions, the composition of major elements for citrus nutrient solution can be modified as follows: 27.1, 16.5, 66.0, 80.0, and $24.0mg\;L^{-1}$ for N, P, K, Ca, and Mg, respectively.

Effects of Oxygen Plasma Treatment on the Wettability of Polypropylene Fabrics

  • Kwon, Young Ah
    • Fashion & Textile Research Journal
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    • v.16 no.3
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    • pp.456-461
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    • 2014
  • The objective of this study is to give PP(polypropylene) fabric a good affinity for water. Oxygen plasma was treated to PP fabrics in a commercial glow discharge reactor with different RF power, discharge pressure, and reaction time. The PP fiber surfaces were characterized by the measurement of contact angle and ESCA. A JEOL scanning electron microscope was used to observe the surface morphology of fibers. The spontaneous water uptake amount of PP fabrics was determined by the demand wettability test. To determine the effect of aging on the surface properties of $O_2$ plasma treated PP, all the above measurements of the samples were carried out after 1, 7, 30, 60, and 150 days. The results are as follows. The PP fiber surfaces treated by $O_2$ plasma treatment have a chemical composition that consisted of various oxygen containing polar groups. Consequently, the contact angles of the treated PP fibers decreased, which improved the water uptake rate of PP fabrics. Surface roughness of the treated PP affected the fabric wettabiity as well. Wettability of the treated PP decreased and leveled off with aging. The $O_2$ plasma treatment is a simple and effective method to increase the water uptake rate of PP fabrics.

RICE UPTAKE AND LEACHING OF 99TC IN DIFFERENT PADDY SOILS CONTAMINATED ACCORDING TO TWO CONTRASTING SCENARIOS

  • Choi, Yong-Ho;Lim, Kwang-Muk;Jun, In;Kim, Byung-Ho;Keum, Dong-Kwon
    • Journal of Radiation Protection and Research
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    • v.40 no.4
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    • pp.231-243
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    • 2015
  • Four different paddy soils collected around the Gyeongju nuclear site were treated with $^{99}TcO_4{^-}$ solution under the assumption of two contrasting contamination scenarios. Scenario I (SN-I) is for a pre-transplanting deposition of $^{99}Tc$ followed by plowing, whereas SN-II is for its deposition onto the water surface shortly after transplanting. Rice plants were grown in lysimeters in a greenhouse. Plant uptake of $^{99}Tc$ was quantified with the $TF_{area}$ ($m^2{\cdot}kg^{-1}-dry$). The SN-II $TF_{area}$ values for straws and brown rice, having been generally higher than the SN-I values, were within the ranges of $6.9{\times}10^{-3}{\sim}4.1{\times}10^{-2}$ and $5.2{\times}10^{-6}{\sim}7.3{\times}10^{-5}$, respectively. Sorption onto clay seems to have decreased $^{99}Tc$ uptake in SN-I, whereas it may have had an insignificant effect in SN-II. A phenomenon characteristic of submerged paddy soil, i.e., the development of a thin oxic surface layer may have greatly affected the rice uptake of SN-II $^{99}Tc$. The surface-water concentrations of $^{99}Tc$ were much higher in SN-II than in SN-I. For the percolating water, however, the opposite was generally true. At most 1.3% of the applied $^{99}Tc$ were leached through such percolation. The use of empirical deposition time-dependent $TF_{area}$ values was considered desirable in assessing the radiological impact of a growing-season deposition of $^{99}Tc$ onto paddy fields.

Studies on the Growth Characters and Nutrient Uptake Related to Source and Sink by Cool Water Temperature at Reproductive Growth Stage III. Influence of Growth Characters and Nutrient Uptake Related to Panicle by Different Water Temperature and Water Depth (생식생장기 냉수온이 벼의 Source와 Sink 관련형질 및 양분흡수에 관한 연구 III. 관개수온과 수심이 수의 관련제형질 및 양분흡수에 미치는 영향)

  • 최수일
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.31 no.2
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    • pp.242-248
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    • 1986
  • To study the effect of cold water irrigation at the reproductive growth stage of rice plants on several growth characters related to source and sink and nutrient uptake, the present experiment was carried out under the different conditions of water temperature and water depth. Deep irrigation with normal temperature water increased culm length, panicle length and panicle exsertion but with cold water resulted adversely. Most sensi-tive response in 5 cm water-depth appeared at reduction division stage and in 20 cm depth at panicle formation stage. Secondary branches and spikelets were increased in number by deep irrigation with normal temperature water, but decreased and degenerated by deep irrigation with cold water at panicle formation stage resulting in high spikelet sterility and low grain filling. Deep irrigation with normal temperature water increased the contents of total nitrogen, phosphate, potassium and silicate in leaf blades, branches and chaff. However, cold water irrigation reduced the uptake of phosphate, potassium and silicate except nitrogen particularly in deep irrigation. Ratios of phosphate, potassium and silicate to total nitrogen content were decreased by cold water irrigation. Branches seemed to have higher requirements for phosphate, potassium and silicate than leaf blades and chaff. Silicate-to-total nitrogen ratio in leaf blades, branches and chaff had significant correlations with yield showing closer relationship between yield and the ratio of silicate to total nitrogen in branches in particu-lar.

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Biological Toxicity Evaluation of Heavy Metal using Oxygen Uptake Rate on Activated Sludge Process (호흡율 측정에 의한 활성슬러지의 중금속 생물독성평가)

  • Ahn, Woo Jung;Baek, Seung-Kyu
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.3
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    • pp.279-285
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    • 2007
  • Toxicity evaluations using oxygen uptake rate (OUR) on activated sludge process were investigated. On toxicity evaluations of heavy metals, all toxicants in experiments decreased OUR with respect to the concentrations of the toxicants, while high toxicities with cyanide and mercury were observed respectively. On toxicity evaluations of composite heavy metals, composite toxicities had similar results as to the total sum of each toxicants that presents accurate toxicity evaluation using OUR. From these results, it is concluded that activated sludge is effective indicator for toxicity evaluation on wastewater of biological treatment plants.

Dissolution of Protons in Oxides

  • Norby, Truls
    • The Korean Journal of Ceramics
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    • v.4 no.2
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    • pp.128-135
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    • 1998
  • The paper gives a brief introduction to protonic defects and their chemistry, thermodynamics and transport in oxides. The temperature dependence of the equilibrium concentration of protons is illustrated and compared for different acceptor-doped oxides. The difficulties of saturating as well as emptying the oxides of protons are discussed. In order to illustrate the possibility of lattice relaxation of defects, a conceptual study is made of a case where the enthalpy of dissolution of protons(water) at the cost of oxygen vacancies is assumed dependent on the concentration of vacancies. It is shown how this changes the behavior of hydration curves vs temperature and water vapour pressure. finally, a discussion is given on the water uptake in heavily oxygen deficient oxides; how water uptake may affect order-disorder in the oxygen sublattice and eventually lead to defective, disordered or ordered oxyhydroxides or hydroxides of potential interest as intermediate temperature proton conductions.

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Evaluation of Optimum Moisture Content for Composting of Beef Manure and Bedding Material Mixtures Using Oxygen Uptake Measurement

  • Kim, Eunjong;Lee, Dong-Hyun;Won, Seunggun;Ahn, Heekwon
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.5
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    • pp.753-758
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    • 2016
  • Moisture content influences physiological characteristics of microbes and physical structure of solid matrices during composting of animal manure. If moisture content is maintained at a proper level, aerobic microorganisms show more active oxygen consumption during composting due to increased microbial activity. In this study, optimum moisture levels for composting of two bedding materials (sawdust, rice hull) and two different mixtures of bedding and beef manure (BS, Beef cattle manure+sawdust; BR, Beef cattle manure+rice hull) were determined based on oxygen uptake rate measured by a pressure sensor method. A broad range of oxygen uptake rates (0.3 to 33.3 mg $O_2/g$ VS d) were monitored as a function of moisture level and composting feedstock type. The maximum oxygen consumption of each material was observed near the saturated condition, which ranged from 75% to 98% of water holding capacity. The optimum moisture content of BS and BR were 70% and 57% on a wet basis, respectively. Although BS's optimum moisture content was near saturated state, its free air space kept a favorable level (above 30%) for aerobic composting due to the sawdust's coarse particle size and bulking effect.

The Effects of Lead Exposure on Glutamatergic Nervous System in Rat Cerebellar Cells

  • Yi, Eun-Young;Ma, Young;Choi, Woo-Joung;Lim, Dong-Koo
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.211-211
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    • 1996
  • Changes in glutamate release and uptake on cerebellar cells after the chronic exposure to lead were investigated. Rats were received 0.25% lead acetate in drinking water from the beginning of the pregnancy. The control group was given 0.125% sodium acetate in drinking water. The cerebellar cells from 7 or 8 day-old pups were cultured. Amino acid release from cerebellar granule cells and the glutamate uptake into cerebellar glial cells were measured using HPLC-ECD. Basal glutamate release and NMDA-induced glutamate release didn't show significant difference. However, the other amino acids in the granule cells obtained from lead exposed pups were less released than the control after the stimulation by NMDA (50$\mu$M). SNAP-induced (50$\mu$M) glutamate release was significantly reduced in granule cells prepared from lead exposed pups. The basal glutamate uptake in glial cells didn't show any difference. However, the uptake in glial cells prepared from lead exposed pups was significantly less blocked by PDC (24$\mu$M) compared to the control group. These results indicate that lead exposure to the mother might affect the Excitatory amino acid system during the development of the offspring.

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