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  • 1
    Electronic Resource
    Electronic Resource
    An infinite sum of products of Jacobi polynomials (1988)
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 29 (1988), S. 2175-2177 
    Details
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: Starting with a formula by Noble [Proc. Cambridge Philos. Soc. 59, 363 (1963), Eq. (16)] for a certain sum of products of Jacobi polynomials, another sum of this type is evaluated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.528144
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  • 2
    Electronic Resource
    Electronic Resource
    Effects of zinc doping of the antimeltback layer on 1.55-μm InGaAsP/InP lasers (1985)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 57 (1985), S. 723-726 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Broad-area InGaAsP/InP lasers emitting at 1.55 μm have been fabricated from material grown by liquid phase epitaxy. The effects of different levels of zinc doping of the antimeltback layer combined with light doping (≤5×1017 cm−3) of the InP cladding layers have been studied. Threshold current densities of 2.1–2.3 kA cm−2 are found under a range of zinc-doping levels. The quantum efficiencies are highest, approximately 19% per facet, when the antimeltback layer is undoped. With zinc doping, the quantum efficiencies drop by a factor of 2–3. Photoelectrochemical etching has been used to reveal the p-n junction. The etching shows that the zinc doping yields an increase in the small scale variations in the placement and abruptness of the p-n junction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.334718
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  • 3
    Electronic Resource
    Electronic Resource
    Staggered hollow-bore CO2 waveguide laser array (1987)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 51 (1987), S. 1057-1059 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A modified hollow-bore ridge waveguide, utilizing a staggered ridge geometry, has been used successfully to obtain single-frequency operation from an array of CO2 waveguide lasers. The gain volume of the array is equivalent to six waveguide lasers of 37 cm length and 2.25×2.25 mm2 cross section. The output power from the sealed-off device reached 68 W cw. Stable single-frequency operation in the antisymmetric supermode was observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.98790
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  • 4
    Electronic Resource
    Electronic Resource
    Thermal acclimation in selected tissues of the fathead minnow, Pimephales promelas rafinesque (1985)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of fish biology 26 (1985), S. 0 
    Details
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Environmental variables besides temperature such as length, weight, sex, and photoperiod were shown to affect the metabolic rate in gill and white muscle tissue. This required statistical adjustment to account for these factors. Oxygen consumption rates for gill tissue were greater following cold acclimation at all determination temperatures. This suggests thermal compensation had occurred. Metabolic rates for white muscle tissue showed inverse compensation between 7 °C and 15 °C, but little compensation was evident between 15 °C and 23 °C. Both gill and white muscle tissue had Q10 values ranging between 1–00 and 2–00. These are lower than values previously recorded for fathead minnows.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1095-8649.1985.tb04286.x
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  • 5
    Electronic Resource
    Electronic Resource
    Technical note: Occurrence of o-tyrosine in non-irradiated foods (1988)
    Oxford, UK : Blackwell Publishing Ltd
    International journal of food science & technology 23 (1988), S. 0 
    Details
    ISSN: 1365-2621
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2621.1988.tb01051.x
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  • 6
    Electronic Resource
    Electronic Resource
    Zooplankton abundance, community structure and dynamics in relation to inorganic turbidity, and their implications for a potential fishery in subtropical Lake le Roux, South Africa (1986)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 16 (1986), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SUMMARY. 1. The abundance and composition of entomostracan zooplankton were studied between 1977 and 1984 in relation to abiotic and biotic conditions in Lake le Roux (LLR), a large silt-laden reservoir on the Orange River formed in 1976. The community consisted of Metadiaptomus meridianus, Lovenula excellens (Calanoida), Daphnia gibba, D. barbata, D. longispina and Moina brachiata (Cladocera), and various Cyclopoida.2. Zooplankton biomass varied seasonally from winter lows below 50 mg m−2 dry wt at temperatures of 9–10°C to summer peaks generally above 1000 mg m−2 at 21–23°C. It correlated strongly and positively with prevailing water temperature and transparency but only weakly with chlorophyll concentration.3. Mean annual zooplankton biomass, which varied four-fold (97–408 mg m−2) in 7 years, increased with annual mean transparency (23–75 cm Secchi depth) and especially with summer heat content (33–230 degree-days above 20°C) which was itself positively correlated with transparency.4. Daphnid species showed most annual variation in abundance. Large forms(D. gibba and D. barbata) were scarce or absent in two years of very low transparency and low planktivore abundance. The smaller D. longispina developed once during clearer conditions when more fish were present. Copepod biomass also varied inversely with turbidity, but was not as severely reduced at high turbidities.5. Smallmouth yellowfish(Barbus aeneus: Cyprinidae) is the principal planktivore and candidate fishery species in LLR. It feeds selectively on Lovenula and large daphnids. Catches and growth rates of yellowfish varied directly with the abundance of zooplankton, particularly large food forms, and with water transparency. High turbidity and associated food limitation seems to reduce standing stocks especially of the daphnid zooplankton more than the effects of fish predation.6. Spawning of yellowfish depends upon the release of water from an upstream reservoir which concurrently reduces transparency and thus zooplankton availability in LLR. Transparency values above 30–35cm SD appear necessary for the development of sufficient and suitable zooplankton to benefit the fishery.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1986.tb00976.x
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  • 7
    Electronic Resource
    Electronic Resource
    Zooplankton feeding rates in relation to suspended sediment content: potential influences on community structure in a turbid reservoir (1988)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 19 (1988), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SUMMARY. 1. Changes in zoopiankton composition and abundance in Lake le Roux, a turbid subtropical reservoir on the Orange River in South Africa, were correlated with changes in water transparency (related to suspended sediment levels) during a 7 year field study. Results of radiotracer studies of the effect of mineral turbidity on zooplankton feeding rates which potentially influence competitive ability, and thus community structure, are reported here.2. Feeding rates of five zooplankters were very variable, but consistently declined with rising turbidity: rates of decline differed between species. A regression estimate of the critical turbidity threshold at which food intake matched the estimated respiratory need was derived for each species. This yielded the following “turbidity-tolerance” ranking: Moina brachiata Jurine 〉 Metadiaptomus meridianus (van Douwe) ×Daphnia gibba Methuen 〉 D. barbata Weltner 〉 D. longispina O. F. Muller. The consistency between this ranking and one based upon abundance-transparency relationships in the field study suggests that community structure is related to differential feeding capabilities, although other influences are not excluded.3. Tests on D. gibba and M. meridianus failed to reveal any detectable feeding rate saturation (incipient limiting food level) below 1.2mg 1−1 C. The relative reduction in feeding rates at elevated turbidity was nearly 3 times greater for the daphnid than the copepod over a range of food concentrations, and considerably reduces the competitive ability of this (and other) daphnids. The turbidity tolerance disparity between Moina and the daphnids demonstrates a more complex situation than a simple copepod/cladoceran dichotomy. These findings and their implieations are discussed in relation to wider features of zooplankton ecology.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1988.tb00334.x
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  • 8
    Electronic Resource
    Electronic Resource
    Population dynamics and production of five crustacean zooplankters in a subtropical reservoir during years of contrasting turbidity (1987)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 18 (1987), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SUMMARY 1. The temporal dynamics and demography of Meta-diaptomus meridianus (Van Douwe), Lovenula excellens Kiefer. Daphnia gibba Methuen, D. barbata Weltner and Moina brachiata Jurine were studied for 2 years in a small bay of Lake le Roux (Orange River, South Africa). Total zooplankton biomass and population density were 1.4–3 times higher during the less turbid conditions of 1982/83 (Secchi depth transparency around 35 cm) than they were at around 25 cm Secchi depth during 1981/82, when D. barbata was absent.2. On average, instantaneous birth rates, rates of population change and death rates varied only slightly between years. Birth and death rates were considerably higher above 15°C than below 15°C. These rates correlated with one another and with zooplankton abundance both inter- and intra-specifically suggesting that competitive interactions were important in population regulation. Mortality rates varied more strongly and consistently in a density-dependent direction than did birth rates. In addition to depressed fecundity, the inferred survival of young was poor and population growth low, possibly because food shortage caused high post-natal mortality.3. Estimates of annual production derived from finite birth rate values varied consistently with annual differences in biomass, and amounted to between 6 and 10 g m−2 y−1 dry wt. Annual P/B values varied from around 20 for the daphnids to 55 for the copepods and 75 for Moina. Apart from the latter, whose annual P/B ratio virtually doubled from 45 to 75 following reductions in turbidity, annual differences in P/B ratio were slight.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1987.tb01315.x
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  • 9
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    Unknown
    The Obverse Side of Aristophanes (1897)
    London : Periodicals Archive Online (PAO)
    The Contemporary Review. 71 (1897:Jan./June) 662 
    Details
    ISSN: 0010-7565
    Topics: General, Interdisciplinary
    URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pao:&rft_dat=xri:pao:article:0274-1897-071-00-000053
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  • 10
    Electronic Resource
    Electronic Resource
    Observations of nitric oxide fluxes over grass (1989)
    Springer
    Journal of atmospheric chemistry 9 (1989), S. 447-463 
    Details
    ISSN: 1573-0662
    Keywords: Eddy correlation ; nitric oxide ; surface fluxes ; soil emissions ; rapid chemical reactions ; dry deposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Eddy correlation measurements of NO vertical flux were made periodically from October 1983 through June 1984 at a height of eight meters above grass in northeastern Illinois, U.S.A. From 207 data points, each representing a 25 min average, 19 daytime cases and 8 nighttime cases were selected on the basis of steady, nonadvective atmospheric conditions. Each case was represented by a set of data constituting a 3 to 5 hr average. Concentrations of O3, NO, and NO y (from which NO2 was inferred) and local atmospheric and surface conditions also were measured, to provide the information necessary to assess the relative importance of surface deposition, surface emission, and air chemistry on the observed NO flux. On the basis of a linear regression analysis applied with independent variables representing physical, chemical, and biological processes, surface uptake of NO was very small for data primarily collected in the daytime during spring, and measured deposition velocities at a height of 8 m were very small, much smaller than expected for NO2. For the same time period, the surface emission rates of elemental nitrogen in NO were in the range of 1.4 to 4.2 ng m-2 s-1 for moist, unsaturated soils at temperatures near 15° C. These emissions were partially masked in the measured fluxes by rapid in-air chemical reactions involving O3 and NO2. The effects of rapid in-air chemical reactions involving O3 were to decrease the (upward) flux of NO with height. While the information collected at night was too limited to strongly support hypotheses concerning emissions and deposition, a pathway for NO production by reactions involving NO3 and related compounds was indicated. For daytime conditions, this production pathway is not evident, probably because of the relatively strong effects of photochemical reactions involving NO, NO2, and O3.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00114756
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