3,597 research outputs found
Self-supported aluminum thin films produced by vacuum deposition process
Self-supported aluminum thin film is produced by vacuum depositing the film on a polyvinyl formal resin film and then removing the resin by radiant heating in the vacuum. The aluminum film can be used as soon as the resin is eliminated
Camera shutter is actuated by electric signal
Rotary solenoid energized by an electric signal opens a camera shutter, and when the solenoid is de-energized a spring closes it. By the use of a microswitch, the shutter may be opened and closed in one continuous, rapid operation when the solenoid is actuated
On Chromospheric Variations Modeling for Main-Sequence Stars of G and K Spectral Classes
We present a method of chromospheric flux simulation for 13 late-type
main-sequence stars. These Sun-like stars have well-determined cyclic flux
variations similar to 11 yr solar activity cycle. Our flux prediction is based
on chromospheric HK emission time series measurements from Mount Wilson
Observatory and comparable solar data. We show that solar three - component
modeling explains well the stellar observations. We find that the 10 - 20% of K
- stars disc surfaces are occupied by bright active regions.Comment: 8 pages, 2 figure
Existence theorems in the geometrically non-linear 6-parametric theory of elastic plates
In this paper we show the existence of global minimizers for the
geometrically exact, non-linear equations of elastic plates, in the framework
of the general 6-parametric shell theory. A characteristic feature of this
model for shells is the appearance of two independent kinematic fields: the
translation vector field and the rotation tensor field (representing in total 6
independent scalar kinematic variables). For isotropic plates, we prove the
existence theorem by applying the direct methods of the calculus of variations.
Then, we generalize our existence result to the case of anisotropic plates. We
also present a detailed comparison with a previously established Cosserat plate
model.Comment: 19 pages, 1 figur
Seasonal Changes in Water Quality and Primary Productivity in Doe Valley Lake
Primary productivity and water quality were studied in Doe Valley Lake, a 147-hectare impoundment on Doe Run, a spring-fed stream in Meade County, Kentucky, from 13 June 1969 to 31 July 1972. Doe Valley Lake is monomictic during most winter seasons, but it is dimictic during more severe winters because of its morphometry and location on the borderline climatic region for dimictic lakes (37° N latitude). Oxygen depletion in the hypolimnion is severe, and anaerobic conditions usually prevail by late June. A hypolimnetic areal deficit of 0.038 mg/cm2/day was calculated. Supersaturation of oxygen in the epilimnion was common, and metalimnetic maxima exceeded 150 percent saturation in spring and early summer.
Primary productivity ranged from 44 to 1,192 mgC/m2/day and annual rates at Stations I and III were 277 and 255 gC/m2/yr, respectively. Productivity fluctuated considerably at Station I as a result of turbidity, but average daily rates and chlorophyll levels were higher than at Station III. Periodic flooding drastically lowered productivity and phytoplankton standing crops. Negative or low correlations were found between productivity and turbidity, pH, alkalinity, nitrates, and phosphates. The relationship between productivity and standing crop of phytoplankton varied throughout the year but positive correlations were observed on an annual basis. Chlorophyll a levels correlated fairly well with net phytoplankton. Except during summer, nannoplankton contributed more than 50 percent of the total carbon assimilation.
The inflowing stream, Doe Run, contributes valuable quantities of nutrients including carbon, nitrogen, phosphorus, and sulfur that enhance the productivity of the lake. Degradation of allochthonous leaf materials introduces significant amounts of carbohydrates, proteins, and lipids into the lake ecosystem, but inflow patterns characteristic of a spring-fed stream greatly influence the fate and availability of these nutrients
Information Literacy at Augustana: A Programmatic Approach
Information literacy programs, and the factors that influence their development and structure, can vary significantly from institution to institution. Credit-bearing discipline-specific information literacy courses are a rare and valuable component of an undergraduate educational experience and form the basis of Augustana\u27s information literacy program. This article provides an overview of the development, implementation, successes, and drawbacks of the credit-bearing discipline-specific information literacy courses at the Augustana Campus of the University of Alberta (Camrose, Alberta, Canada). Additional program components including Augustana\u27s annual information literacy workshop, information literacy awards, information literacy DVD, and marketing/branding, are discussed
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Complete Genome Sequence of the Citrobacter freundii Type Strain.
Citrobacter freundii is a species of facultative anaerobic Gram-negative bacteria of the family Enterobacteriaceae The complete genome is composed of a single chromosomal circle of 4,957,773 bp with a G+C content of 52%
Evaluation of ozone difluoride as a liquid propellant additive Final report
Ozone difluoride evaluated as liquid propellant additiv
Observation of String Breaking in QCD
We numerically investigate the transition of the static quark-antiquark
string into a static-light meson-antimeson system. Improving noise reduction
techniques, we are able to resolve the signature of string breaking dynamics
for n_f=2 lattice QCD at zero temperature. This result can be related to
properties of quarkonium systems. We also study short-distance interactions
between two static-light mesons.Comment: 27 pages, 22 figures, changed decimal place of errors in 3 entries of
Table, corrected reference
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