This thesis investigates a way to fabricate P-N junctions by
percussive welding. The theoretical basis of percussive welding, design
considerations of the apparatus used, and the electrical characteristics
of the junctions were the main objectives of this investigation.
P-type silicon wafers and gold wire doped with arsenic as a
N-type...
Wheat varieties of differential tolerance to Al were used in a
series of nutrient solution experiments to study the inhibitory effects
of Al on growth and nutrient uptake. The pH and the Al and P concentrations
were rigorously maintained to prevent the confounding
effects of Al and P precipitation and...
An investigation of Mn uptake by five-day-old excised barley
roots revealed that a metabolically-mediated process was involved.
In short-term experiments, the rate of Mn absorption was comparable
to that of the macronutrient cations. Like other metabolically
absorbed cations, the Mn absorption rate was a direct function of
the ambient concentration...
The relationships between zinc, iron, and phosphorus in sweet
corn were investigated under field and greenhouse conditions. The
soils used in this study (both acid and calcareous) were low in available
zinc and phosphorus.
The experiments received standard, uniform rates of nitrogen
potassium, magnesium, and sulphur. Corn was used as...
Cucumber, pea, bean, and corn excised roots were used to
assess species differences in metabolic uptake of calcium It was
found that Ca was mostly taken up by these root systems by non-metabolic
processes. The apparent free space ranged from 26 to 28
percent of the total root volume and...
This study was initiated to determine the relative efficiency
of systematic, stratified and simple random sampling for crown area
and tree frequency estimation of five of the major forest types found
in the Pacific Northwest. Several of the more common methods of
estimating spatial distribution coefficients were evaluated. Finally
the...
This study was initiated to determine the accuracy and limits
of the height-accumulation method of measuring tree volume and
surface area for Pacific Northwest second-growth trees. Thirty
trees were selected from various thinning treatments in a 55 year
old Douglas-fir forest. Each tree was measured with the highly
accurate Barr...
Thermal decomposition of several di-p-toluenesulfonylhydrazones
was studied. It was found that the carbene decomposition
of tetramethyl-1,3-cyclobutanedione, di-p-toluenesulfonylhydrazone
gave two products resulting from
rearrangement. One was identified as 2,5-dimethyl-1,3,4-hexatriene. A tentative structure for the second was
proposed. During the course of the study, a more convenient
procedure for thermal decompositions was...
The purpose of the study was to determine an emergence
rhythm, its period, and the developmental stages susceptible to
emergence synchronization in the leafcutter bee Megachile rotundata
(Fabricius). An attempt was made to determine if an oxygen consumption
rhythm was present in the pupal and adult stages of the
alkali...
The rhythms of emergence, oxygen consumption, and activity
were studied in Megachile rotundata with the object of comparing the
results to the major properties of the biological clock such as temperature
independence, susceptibility to light synchronization, and
entrainment. A further objective was to compare the three rhythms
to determine if...