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1.
GANAPATHY MUTHUKUMAR ELLEN C. JENSEN ANN W. NICKERSON MARK K. ECKLES KENNETH W. NICKERSON 《Photochemistry and photobiology》1991,53(2):287-291
Abstract— Penicillium isariaeforme is a photomorphogenic fungus which produces upright bundles of conidia-bearing mycelia (called coremia) when grown on a defined medium in visible (450–500 nm) light. We found that exogenous Ca2+ ions could substitute for light. In the dark 1–2 m M Ca2+ triggered coremia formation. Dark induction of coremia was specific for Ca2+ in that it could not be duplicated by 50 m M Ba2+ , Fe2+ , Mg2+ , Mn2+ , Sr2+ , or Zn2+ . Additionally, light-induced coremia formation was inhibited by both KI (2.5 m M ) and phenylacetic acid (0.25 m M ). 相似文献
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A comprehensive set of spectra for the benzene cation and the perdeuterated benzene cation has been recorded with full rotational resolution using zero kinetic energy photoelectron spectroscopy (ZEKE) at high resolution (up to 0.2 cm?1), using a slow-rising extraction pulse. With different rovibronic levels in the S1 6l state as intermediate resonance, the rotational transitions to the vibronic ground state of the cation have been recorded using two-colour, two-photon resonance enhanced multiphoton ionization. A simple spectator model has been employed to simulate the intensities of the ZEKE transitions. By fitting the simulations to the recorded spectra, improved values for the rotational constants and the Coriolis coupling parameters of benzene and perdeuterated benzene have been obtained. The CC and CH bond lengths of the cation have been deduced. The spectator model is shown to be reliable despite the fact that no specific allowance is made for the effect of final state interactions on the signal intensity. 相似文献
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The specular-reflectance technique has been used to develop an experiment for an undergraduate instrumental course that demonstrates the ability of Fourier transform IR spectroscopy to routinely procure vibrational spectra of thin films of polymethylmethacrylate on reflective copper discs. The experiment introduces students to the specular-reflectance technique and its selection rules, then demonstrates how they reveal the orientational constraint of adsorbed molecules within a thin film. Suggestions are included on how to expand the experiment to demonstrate the relationships between film thickness and the amount of light absorbed. 相似文献
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On the Accurate Determination of Search Directions for Simple Differentiable Penalty Functions 总被引:2,自引:0,他引:2
We present numerically reliable methods for the calculationof a search direction for use in sequential methods for solvingnonlinear programming problems. The methods presented are easyto adapt to such problems as locating directions of negativecurvature and linear infinite descent. Encouraging numericalresults are included. 相似文献
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Abstract Evaluation of potential economic consequences of alternative management actions requires an understanding of how the biological stock will be affected by the management action and an understanding of the response of economic systems to changes in the timing, magnitude, and size distribution of harvests and changes in the location and catchability of the biological stock. We use a hybrid structural time series model to represent Pacific halibut (Hippoglossus stenolepis) stock and recruitment dynamics and a system of structural equations to represent supply and demand relationships for Pacific halibut from Alaska and British Columbia. Model simulations explore the economic effects of changes in recruitment success, growth rate, and carrying capacity, and changes in international supplies of halibut. 相似文献
8.
Chandrasekhar’s formalisms for the transfer of polarized radiation are used to explain the observed dust scattering polarization
of brown dwarfs in the optical band. Model polarization profiles for hot and young directly imaged extrasolar planets are
presented with specific prediction of the degree of polarization in the infrared. The model invokes Chandrasekhar’s formalism
for the rotation-induced oblateness of the objects that gives rise to the necessary asymmetry for yielding net non-zero disk
integrated linear polarization. The observed optical polarization constrains the surface gravity and could be a tool to estimate
the mass of extrasolar planets. 相似文献
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