Due to its high strength/weight ratio, 7075 aluminum alloy has
been widely used as an aerospace material. However, it has relatively low fatigue strength and low fracture toughness in the T6
condition. Thermomechanical processing, including pre-cyclic loading and stretching at high and ambient temperatures, has been investigated with the aim...
The force, temperature, and time relationships were
investigated by using oscilloscope measurement techniques. Force was measured using a strain gage and the dynamic
response recorded with a polaroid oscilloscope camera.
Temperature was measured with a tungsten-rhenium thermocouple
and recorded in the same manner. Residual stress
measurements were made to determine...
A mechanism for filiform corrosion of aluminum is proposed
based on experimental evidence and the known aqueous chemistry of
the trivalent aluminum ion. Experimental methods utilized include
autoradiographs with Cl³⁶; pH paper determination of the filiform
head pH; activator concentration and activation period as they affect
filiform growth.
The pH...
The toxicity of aluminum (Al) to wheat (Triticum aestivum
Host) was studied under controlled conditions using a technique
designed to evaluate the recovery of root growth following a relatively
brief (48 hour) exposure to nutrient solutions containing
Al, When wheat seedlings were exposed to a minimum critical
concentration of Al,...
The progression and consequences of aluminum toxicity were
studied microscopically in the root tips of four wheat varieties
representing different classes of Al tolerance. The root tips studied
were collected from seedlings grown in nutrient solution cultures containing
either sublethal or lethal Al treatments which were unique for
each variety....
The time-concentration interaction of Al toxicity in the root
meristems of Brevor wheat was studied using the L.D. 50 as a criteria
for Al damage. The L.D. 50 represented a precise, well defined
degree of biological damage which was easily reproduced under conditions
where factors like temperature, pH, nutrient concentration,...
A technique previously designed to screen wheat cultivars and
segregating populations for tolerance to Aluminum utilizing nutrient
solutions in growth chambers was found to be efficient in differentiating
among cultivars of wheat, rye, and triticale for tolerance to Al
under greenhouse conditions. A 5°C increase in temperature, from
25°C to...
The development and optimization of a fluorometric reaction
rate method for the determination of aluminum is described.
Modifications to existing instrumentation permit automatic
monitoring and reporting of measurement conditions. Automatic
correction of measured analytical signals is provided if monitored
parameters deviate from optimum values. A computer controlled
standard addition procedure...