Samarium
(III)
and
promethium
(III)
were
studied
by
chronopotentiometry
in
a
molten
LiCl-KC1
eutectic.
Tungsten
electrodes
were
used
to
avoid
alloying
effects
encountered
with
platinum
electrodes.
Adsorption
phenomena
were
observed
which
prevented
the
study
of
any
kinetic
effects.
The
quarter
wave
potentials
were
measured
as:
Sm(III)
=
0.95
±
0.05...
Optimization of the galvanovoltammetric determination of dissolved
chlorine in a flowing stream was achieved through the use of
an analog computational device and improvements in the design of the
galvanovoltammetric cell and accompanying electronic circuitry. An
analysis system, applicable to industrial use over a range of flow
rates and dissolved...
An automatic digital titrator for use in potentiometric titrations
is described. The automatic titrator described provides
a permanent digital and analog record of all titrations. The modular
units which combine to form the automatic titrator are described
individually. Accuracy achieved by the titrator on successive
acid-base titrations of ammonia in...
A procedure is described for the optimization of a previously
described continuous analysis adaptation of the Pearl-Benson or
nitroso method for estimation of spent sulfite liquor (SSL) or ligno-sulfonates.
The optimized procedure has a response time of 6.5 minutes. In order to monitor samples whose SSL concentration is
between 0...
A new pulse method for measuring differential double layer
capacitances has been developed in this work. The technique is based
on the determination of the cell time constant which, for an ideally
polarized test electrode-solution interface, is composed of the double
layer capacitance and solution resistance. By applying small step...
Many different aspects of the determination of dissolved oxygen
by controlled potential coulometry were investigated to find a means
of measuring the oxygen content of natural waters. Rapid
sampling techniques, simplicity of operation, and rugged structural
features were stressed. Cells were designed to operate by either
internal electrolysis or external...
An automatic, continuous analyzer has been developed which
is suitable for estimating the level of spent sulfite liquors (SSL) in
laboratory samples. The analyzer makes use of a version of the
Pearl-Benson, or nitroso method, and, in its present form, is
useful for samples whose actual SSL solids concentrations are...
Nitrogen is a contaminant of niobium and tantalum adversely
affecting the workability of the metal. With recent interest in the
refractory metals, one problem the chemical analyst must solve
is the accurate determination of nitrogen in niobium and tantalum
at very low levels. The usual method of assaying for nitrogen...
As with many pairs of metals, the electrodeposition of Pb-Tl, Cu-Cd, and Cu-Ni at solid electrodes yielded partial polarization curves shifted from the polarization curves of the single metals. The curves for the more noble metals (Pb, Cu) were shifted negatively while the less noble metals'(Tl, Cd, Ni) curves were...
An all-glass gas chromatograph was developed for the analysis
of corrosive metal halides. Included in the apparatus is a new liquid
sampling system designed for fast repetitive sampling of corrosive
liquids in an inert atmosphere. A flame photometer detector was developed
to permit the detection of corrosive solutes in the...
A Heath EUW-20A Servo-Recorder was converted to a self-balancing, recording Wheatstone bridge. The EUW-20A 10000Ω slide-wire was used as the variable resistance arm of the bridge, the
servo-amplifier was used as the bridge unbalance signal detector,
and the servo-motor was used to balance the bridge automatically.
The bridge was arranged...
AT-cut piezoelectric quartz crystals coated with low vapor
pressure materials are evaluated as digital transducers in completely
digital detection systems for monitoring gas streams. Mathematical
relations describing the detectors are developed and tested. Specific
application is made to monitoring gaseous sulfur compounds commonly
found in stack effluents of pulp mills....
The electrochemistry of the lithium-potassium-sodium
carbonate-borate melt was explored by voltammetry and chrono-amperometry. In support of this, a controlled-potential polarograph
and associated hardware was constructed.
Several different types
of reference electrodes were tried before choosing a porcelain membrane electrode containing a silver wire immersed in a silver sulfate
melt.
The...
Aromatic Nitro Compounds. The n-values for the reduction of
the isomers of nitrophenol and nitrobenzoic acid and for several
other nitro compounds are determined in dimethylsulfoxide by controlled
potential coulometry. A procedure is given in which one
mole of nitro compound may be determined with errors of less than
one...
An instrument was developed which performs analysis of the
oxygen content of air by means of a commercial polarographic oxygen
electrode. The oxygen analyzer is part of a portable instrument
which converts the current from the oxygen electrode into a pulse
whose width is proportional to the oxygen concentration. This...
New alloys containing refractory metals have been developed
by the aero-space industry to meet the demand for thermally resistant
materials. The chemical analysis of these alloys has been
handled successfully by the use of ion exchange. Hydrofluoric acid,
either alone or combined with hydrochloric acid, has here-to-fore
been used to...
Voltage scanning coulometry was used to study the effects of
electrode surfaces and metals on the electrochemistry of the ferric-ferrous couple and the silver ion-silver metal couple. The analytical
technique called voltage scanning coulometry is very similar to controlled
potential coulometry. The main difference is that in voltage
scanning coulometry...
The theory and ways of applying a new electroanalytical detectior
method were developed. The method, called galvanovoltammetry,
consists of the measurement of current from the bipolar electrode of
a three electrode cell which consists of a working electrode and a
counter electrode, between which a constant current is applied, and...
The extraction of tantalum fluoride complexes by large cationic
extractants (tetraphenylarsonium ion, TPA, and crystal violet) and
by methyl isobutyl ketone (MIBK) has been investigated as a function
of fluoride concentration using ¹⁸² Ta as tracer. Extractions by the
cationic extractants into chloroform were carried out in the absence
of...
The Kroll Process for the production of zirconium utilizes
the reduction of zirconium tetrachloride with metallic magnesium.
Control of the magnesium content of the final zirconium metal is
essential, as residual magnesium adversely influences the properties
of zirconium.
In this thesis a volumetric method has been presented for the
determination...
A continuous amperometric monitor for aqueous sulfite solutions
has been developed employing the electro-oxidation of sulfur (IV)
in 0. 1 M sulfuric acid at a glassy carbon test electrode. The monitor
employs a hydrodynamic flow cell, in which the solution stream
enters the cell through an orifice impinging on the...
A gas chromatographic procedure was developed for the determination
of nanogram quantities of hydrocyanic acid using a
flame ionization detector. Excellent chromatograms were obtained
on a porous polyaromatic polymer column (Porapak Q) at 60°C. The
procedure was employed for the analysis of HCN in aqueous cyanide
solutions. Solutions as low...
The lack of availability of a single, complete paper on the
analysis of a digital data acquisition system for in situ oceanographic
measurements brought about the present work. In order to compile
an accurate technical paper on such a complex system, it was necessary
to design, construct, and calibrate a...
The purpose of this research was to study the impact
phenomena of a tennis ball striking a hard surface.
Stroboscopic photography was used to collect the ball's
impact images from seven angles of incidence, ranging from
-23 degrees to -70 degrees with zero, top and back initial
spin respectively.
Through...