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Effects of herbicides on wild plants at chromosomal, population, and community levelsTomkins, Darrell Joan January 1975 (has links)
No description available.
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Studies on the urinary estrogens of the domestic fowl.Mathur, Rajesh S. January 1967 (has links)
No description available.
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Survey of techniques for improving performance of organic transistorsChien, Yu-Mo, 1980- January 2007 (has links)
Organic field-effect transistors (OFETs) with region-regular poly(3-hexylthiophene) (rr-P3HT) as active semiconductor were fabricated and characterized. Various methods for improving device performance were investigated. These methods include: the use of dip coating technique (rather than spin coating), thermal annealing, polymer doping with iron chloride (FeCl 3), and stamping of "dry" poly(dimethylsiloxane) (PDMS) stamp before polymer deposition. / Through experimental results, it is clear that thermal annealing increases charge carrier mobility of P3HT OFETs. On average an increase of four times in charge mobility was observed after thermal annealing was performed. Dip coated samples also resulted in higher mobility values than spin coated samples. Highest charge mobility value achieved were was ∼0.02 cm2/Vs for dip coated samples, where as the highest value for spin coated devices was around 6e-3 cm2/Vs. / "Dry" stamping of a PDMS devices yielded devices with higher mobility values by around 100% compared to unstamped counterparts. These devices also exhibited lower parasitic leakage currents. / Devices doped with FeCl3 did not perform very well. It is suspected that it was increased so much that it became impossible to turn off the devices.
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Metabolic injury to bacteria on freezing and storage.Kuo, Shou-Chang. January 1966 (has links)
No description available.
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Substituted iron phthalocyanines : electrocatalytic activity towards O₂ reduction in a proton exchange membrane fuel cell cathode environment as a function of temperatureBaker, Ryan Christopher Colin 11 1900 (has links)
In this thesis five iron phthalocyanines (FePc’s), four of which having different
electron withdrawing or electron donating substituents, were evaluated as 0₂
reduction reaction (ORR) catalysts. The experimental approach simulated a
PEM fuel cell environment using both ex-situ electrochemical techniques and in
situ fuel cell testing.
The kinetic ORR parameters for the FePc species each adsorbed on a
pyrolytic graphite WE were evaluated at four temperatures (20, 40, 60, 80°C) in a
novel half cell using cyclic voltammetry (CV) and rotating disk electrode (RDE)
voltammetry. Kinetic ORR parameters included the overall ORR electron transfer
number, reaction rate constants, cathodic Tafel slopes, electron transfer numbers
in the rate determining step, and electron transfer co-efficients. An increase in
temperature from 60°C to 80°C showed a decrease in the overall electron
transfer number observed for all four substituted FePc species. A mechanism
was also proposed based on the experimental results.
The RDE results were confirmed using a rotating ring disk electrode (RRDE).
From these RRDE results, the fraction of H₂0₂ produced (XH₂₀₂) at the disk
during the ORR was calculated. These XH₂₀₂ values agreed with the overall
ORR electron transfer numbers from the RDE results obtained under the same
conditions.
lron(Il) 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25 — hexadecachioro
29H,31H-phthalocyanine (FePcCI₁₆)was down selected for further investigation as the most stable and active substituted FePc species for the ORR. Both
FePcCl₁₆ and the unsubstituted FePc, were supported on carbon and made into
catalyst inks for carbon fibre paper (CFP) electrode testing, and then evaluated
using CV in the N₂ purged, followed by the air saturated, electrolytes,
respectively.
Finally, MEA’s for fuel cell testing were made using FePc species catalyst ink
cathodes, and commercial Pt/C anodes. The MEA’s were tested using custom
designed and built fuel cell hardware. Open circuit voltages, polarization curves,
and power curves were recorded. Initial results indicated the FePcCI₁₆ MEA’s
showed superior stability, higher open circuit voltages, as well as better
polarization and power curves when compared to the unsubstituted FePc
species.
It was found that FePc species with strongly electron withdrawing
substituents, such as FePcCl₁₆ showed the highest stability and greatest ORR
activity. FePc species, including pyrolized FeNx/C analogues, show much
promise as alternatives to Pt in PEMFC’s, as well as dye sensitized solar cells
(DSSC’s).
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Numerosity and Cognitive Complexity of a Medium as Moderators of Medium Effect on EffortRahimi Nejad, Mona 27 September 2010 (has links)
As a part of loyalty programs in marketing or as incentive plans in companies, mediums have attracted considerable interest from marketing and organizational behavior researchers. Previous studies focused mainly on the effects of mediums on people’s choices and not on the role of moderators of a medium effect. The goal of the present thesis is to study two such moderators namely the numerosity of a medium and the cognitive complexity of mediums. In this study, after a thorough theoretical analysis, experimental data is analyzed to explore the relation between numerosity and cognitive complexity of a medium on individuals’ efforts. Our findings suggest that the medium effect is stronger when a medium is more numerous. Also, a more cognitively complex medium makes the mediums more effective.
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The impacts of agricultural chemicals and temperature on the physiological stress response in fishQuinn, Amie L., University of Lethbridge. Faculty of Arts and Science January 2007 (has links)
Fish are exposed to multiple stressors in their environment. The interactive
effects of pesticide exposure and increased temperature on the physiological stress
response were investigated in a comparative field study with cold-water (whitefish,
Prosopium williamsoni) and cool-water (sucker, Catostomus) fish from the Oldman
River, Alberta, Canada, and in a laboratory study with rainbow trout, Oncorhynchus
mykiss. Physiogical stress indicators were measured, and exposure to pesticides was
estimated using acetylcholinesterase (AChE) inhibition. Species-specific differences in
AChE activities and responses of the physiological stress axis were detected in whitefish
and suckers, suggesting that whitefish are a more sensitive species to temperature and
pesticide stress. In vivo Dimethoate exposure inhibited AChE activity in various tissues
and disrupted the physiogical stress response. Commercial Dimethoate, in vitro, caused a
decrease in viability and cortisol secretion while pure grade Dimethoate did not. The
results from this study can be used in predictions of fish vulnerability to stress. / ix, 137 leaves : ill. ; 29 cm.
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An investigation of the effects of noise on human performanceGuzman Parraga, Aurelio Jose 12 1900 (has links)
No description available.
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Possible circadian rhythm in endothia parasiticaRaiford, Daniel Morgan 08 1900 (has links)
No description available.
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Effects of aircraft emissions on weed species grown in the vicinity of Hartsfield International Airport, Mountain View, GeorgiaWiedl, Stephen Cass 12 1900 (has links)
No description available.
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