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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 28 (1992), S. 0 
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : A numerical simulation model was developed to predict the vertical and lateral percolation losses from a ponded agricultural field. The two-dimensional steady-state unsaturated/ saturated flow equation was solved using the finite-difference technique. A constant ponding depth was maintained at the soil surface with different water table conditions in an application of the model for rice fields bordered by bunds. Field experiments were conducted for two different water table depths to collect data on the spatial distribution of volumetric soil-moisture content for model verification. The measured soil-moisture content values were found to be in close agreement with those predicted by the model.The sensitivity analysis of the model with selected hydrologic conditions shows that the model is most sensitive to the values of saturated hydraulic conductivity, but relatively less sensitive to water table depth, ponding depth, and evaporation rate from the soil surface. It implies that, in a ponded rice field condition, the lateral and vertical percolation losses are mostly governed by the hydraulic conductivity of the soil. The vertical percolation losses were almost equal to the saturated hydraulic conductivity values and, in most cases, these losses increased with deeper water table depths. The lateral percolation losses also increased with deeper water table depths; however, these losses were relatively small in comparison to the vertical percolation losses. The vertical and lateral percolation losses increased with the increase in ponding depths. The lateral percolation losses through the bund decreased when the evaporation losses increased from the soil surface. The results of this study indicate that the percolation losses from a ponded field may be predicted accurately for a wide range of soil and hydrological conditions when the values of hydraulic conductivity, evaporation rate, depth of ponding, and water table depth are accurately known.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: In a long-term growth trial, transgenic tilapia Oreochromis niloticus L. showed a 2·5-fold increase in growth compared with non-transgenic siblings. At 7 months, mean mass of transgenic tilapia was 653 g compared with 260 g for non-transgenic siblings. A significant increase (P 〉0·01) in head: total length ratio, viscera-somatic index and hepato-somatic index was observed in transgenic fish. Female gonado-somatic index (I G) was found to be lower in transgenics than non-transgenic siblings in both mixed and separate culture conditions. Transgenic male I G values were found to be higher in mixed culture and lower in separate culture than that of their non-transgenic siblings. Food conversion efficiency was more than 20% greater in the transgenic fish. In a second shorter-term growth performance trial, the transgenic fish grew to about four times the size of their non-transgenic siblings. A digestibility trial suggested that transgenic tilapia were more efficient utilizers of protein, dry matter and energy. Apparent digestibility of protein and apparent energy digestibility were higher in the transgenic fish.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Intact ovarian follicles, obtained from untreated and human chorionic gonadotropin (HCG) treated Japanese yellowtail Seriola quinqueradiata during different maturational stages, were incubated with radioactive [3H]pregnenolone, [3H]17-hydroxyprogesterone or [14C] androstenedione and steroid metabolites identified by thin layer chromatography (TLC) followed by recrystallization to constant specific activity. In untreated late vitellogenic (0 h) follicles, androstenedione was the major product with smaller amounts of testosterone and oestradiol-17α. In post-vitellogenic (12 h post-injection) intact follicles, androstenedione predominated, and although testosterone and oestradiol-17α were not produced, there were small amounts of 17, 20β-dihydroxy-4-pregnen-3-one (17,20β-P) and 17,21-dihydroxy-4-pregnene-3, 20-dione (11-deoxycortisol). In HCG-treated fish, a steroidogenic shift resulted in the disappearance of testosterone and oestradiol-17 coinciding with the appearance of 17, 20β-P. During early and late final oocyte maturation FOM (24 and 36 h post-injection), there was a five- to seven-fold increase in the production of 17, 20β-P, whereas production of 11-deoxycortisol remained almost the same. During FOM, in addition to 17,20β-P, its 5β-reduced metabolite, 17,20β-dihydroxy-5β-pregnan-3-one (5β-17,20β-P) was synthesized, suggesting a decrease in maturation-inducing 17,20β-P activity. 17, 20β,21-Trihydroxy-4-pregnen-3-one (20β-S) was not synthesized by ovarian fragments in Japanese yellowtail at any maturational stage. The metabolites identified on TLC during FOM were tested to evaluate their maturation-inducing activity in an in vitro bioassay. Of the steroids tested, 17,20β-P was the most effective inducer of germinal vesicle breakdown (GVBD), followed by 5β-17,20β-P. Timely synthesis of 17,20β-P immediately prior to and during FOM as well as its great potency in inducing GVBD in vitro supports the evidence for a physiological role of 17,20β-P as a maturation-inducing hormone in Japanese yellowtail.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Plant breeding 97 (1986), S. 0 
    ISSN: 1439-0523
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Inter-generation correlations between F2-F3, F2-F4 and F3-F4 in six crosses of chickpea were calculated by using individual plant/progeny means. In general, correlation values in case of plant height, seeds per pod and 100-seed weight were higher between F3 and F4 than those between F2 and F3 and F2 and F4. However, inter-generation correlations were mostly non-significant in case of pods per plant and grain yield. These results clearly show that selection in F3 can be fruitful for seeds per pod and 100-seed weight. However, selection for pods per plant and grain yield in early generations may not show any relationship with later generation performance for these traits.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 6868-6870 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: This article presents a novel test method to determine the important load dependent reactance parameters Xd, Xq, and magnet-excited voltage E0 of permanent magnet (PM) motors. The results bring forward a clear picture of the impact of the previous assumption of constant E0 on the value of Xd. As improved accuracy and fast data sampling are required for online control, the traditional method for measuring torque angle is deficient. To this end, a new microprocessor-based digital torque angle measurement system was designed and built. At the same time, a scheme for accurately positioning the zero torque angle is proposed without referring to the interior structure of a motor. The proposed techniques have been successfully employed for a 1 hp laboratory permanent magnet motor.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The formation of mullite via gels prepared from technical ethyl silicate and aluminium chlorides has been studied. Normally, gels prepared specifically with the oxide stoichiometry of mullite (3Al2O3·2SiO2) do not form the mineral mullite on firing to 1200° C in the absence of a mineralizer. However, when the stoichiometric gel is homogeneous (achieved by acidic or neutral catalysts during the gel preparation) firing at 1200° C can lead to an almost quantitative yield of mullite. For a homogeneous gel, the presence of strontium or caesium salts, or an organo-tin compound such as dibutyltin diacetate or dibutyltin oxide during the gel preparation promotes almost quantitative conversion to mullite at about 1000° C. There is a threshold concentration under which conversion to mullite is incomplete, some cristobalite being formed. For the organo-tin compounds, the type of aluminium chloride is unimportant and the way in which water for the hydrolysis step is added is also unimportant. When the gel is non-homogeneous, the product obtained on firing contains cristobalite andα-alumina orγ-alumina, with little mullite, even if strontium or caesium salts, or organ-otin compounds are present. A ceramic bond is formed from alumina and some other refractory grains during firing.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Materials and structures 20 (1987), S. 361-366 
    ISSN: 1359-5997
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract Different mix proportions of sand, cement and rice husk ash (RHA) were studied for use in sandcrete blocks. Optimum water/(cement+RHA) ratios were determined at different mix proportions. Compressive strengths of various mix proportions at 7, 28 and 60 days were also determined. The optimum water/(cement+RHA) ratio increased with rice husk ash contents. Test results showed that up to 40% RHA could be added as a partial replacement for cement without any significant change in compressive strength at 60 days. Compressive strengths of various mix proportions were compared with British Statutory minimum compressive strengths of bricks for various walls and it was found that sandcrete blocks of 1∶5 mortar mixes with 40% RHA (by weight of cement) could be used in both load and non-load bearing walls.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Materials and structures 21 (1988), S. 222-227 
    ISSN: 1359-5997
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract The effects of rice husk ash (RHA) on the various properties of lateritic soil-clay mixed bricks were studied. The effect of firing duration (at a firing temperature of 1000°C) on the properties of bricks was also studied. The measured properties were linear shrinkage, unit weight, compressive strength, 24-hour immersion water absorption and 5-hour boiling water absorption. Both linear shrinkage and unit weight of bricks decreased with increase in the percentage of RHA content. The compressive strength of lateritic soil-clay mixed bricks increased almost linearly with increase in the percentage content of RHA. The bricks which received a 4-hour at 1000°C attained maximum compressive strength. Both 24-hour immersion and 5-hour boiling water absorptions of the bricks were within the permissible limits. The strengths of the bricks were compared with British statutory minimum compressive strengths of bricks for various walls. The bricks are recommended or load-bearing walls.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 257 (1972), S. 380-388 
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Analogue states in28Si are identified through (p, γ) reaction in27Al in the energy rangeE p =0.85–3.0 MeV. There appears hardly any indication of a mixing. Coulomb displacement energy ΔE c for the isobaric pair28Al-28Si is obtained. A least squares analysis is also carried out on all the available experimental results of ΔE c as a function of ¯Z/A 1/3.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell, tissue and organ culture 13 (1988), S. 179-187 
    ISSN: 1573-5044
    Keywords: jackfruit ; shoot proliferation ; in vitro rooting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Successful vegetative propagation of seedling jackfruit (Artocarpus heterophyllus Lam.) has been achieved by in vitro methods. Proliferation from nodal explants was greater than from shoot tips. Of the cytokinins tested, benzylaminopurine (BAP) was more effective than either 2-isopentenyladenine (2iP) or kinetin (Kin) and produced maximum proliferation when used at 5×10-6M. Shoot proliferation was optimal at 30°C with a 12 h photoperiod. Optimal rooting of shoots in vitro was obtained with indolebutyric acid (IBA) at 10-6M. The number and length of roots was significantly increased in 12 h light as compared with the dark.
    Type of Medium: Electronic Resource
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