The photolysis of the aqueous thymine system has been investigated
at 214 nm, 229 nm and 254 nm at room temperature. Products
of photolysis have been identified as hydrogen peroxide, 6-hydroxy-5-
hydroperoxy thymine and tentatively 5-hydroxy-6-hydroperoxy thymine.
These together with thymine loss, were determined quantitatively
under a variety of conditions....
The photochemical reaction between O⁻ ions and F centers
was investigated. The activation energy was determined by the
Arrhenius law to be 0.10 + 0.04 eV for temperature below 180°K.
The diffusion of alpha centers towards the oxide ion was eliminated
as the rate limiting step and the low trapping...
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....
Fluorescence of adenine, guanine, thymine, cytosine, and uracil
has been detected at room temperature in neutral aqueous solution
using a digital signal accumulation technique and right angle fluorescence
detection from solutions with absorbances between 0. 4 and 0. 7.
The quantum yields are respectively 2.6 x 10⁻⁴, 3.0 x 10⁻⁴,...
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...
The oxidation of triethylamine by the two electron oxidant
thallium(III) chloride was studied and the results compared to those
when triethylamine is oxidized by copper(II) halides. This study
requires anhydrous conditions since in an aqueous system thallium(III)
chloride is extensively hydrolyzed and triethylamine causes
precipitation of thallium(III) oxide. Most of...
The analysis of 64 rock samples from Saudi Arabia and three
samples from the axial trough of the Red Sea has been done.
Instrumental neutron activation analysis (INAA) was the analytical
tool used for the analysis of at least 18 and as many as 24 elements
in these 67 rock...
The silicate phases of 11 pallasites were analyzed instrumentally
to determine the concentrations of some major, minor, and
trace elements. The silicate phases were found to contain about
98% olivine with 1 to 2% accessory minerals such as lawrencite,
schreibersite, troilite, chromite, and farringtonite present. The
trace element concentrations, except...
The yields from the oxidation of 4-methylpyrimidine with potassium permanganate were found to increase from 25 to 92 percent by the addition of small amount of potassium hydroxide to the reaction mixture. Pyrimidine-4-carboxylic acid decarboxylates in hot aqueous solution to yield pyrimidine and carbon dioxide. The rate is that decarboxylation...
The infrared absorption spectrum from 3200 cm⁻¹ to 4025
cm⁻¹ of thin crystals of ⁶LiOH (99%⁶Li.) is presented and compared
to the spectrum of [superscript]NLiOH (93%⁷Li). A shift in only one of the band
pairs supports the lattice combinations model and assists in making
assignments for the major features of...
A quadratic programming method was developed for the statistical
analysis of gas chromatographic data. The method was applied to
three types of flavor extracts, peppermint, hops and brewed tea. The
brewed tea data had to be abandoned because of the singularity of its
coveriance matrix. In all cases tried the...
The relative rates of hydrogen abstraction from a series of 13
arylmethanes by the trichloromethyl radical were determined at 70°.
The attacking radical was generated from bromotrichloromethane us
ing benzoyl peroxide as the initiator. The solvent was benzenebromotrichloromethane.
An excellent correlation, with a coefficient
of 0.977, was obtained when the...
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...
Direct current conductivity measurements on KC1:O[superscript]= crystals
were used to determine an enthalpy of 0.42 ev for the dissociation for
anion-vacancy-oxide ion complex.
The entropy of dissociation was
found to be approximately -4x 10⁻⁴ev deg⁻¹. The intrinsic "activation" energy was found to be 1.91 ev as compared to 1.95 ev,...
A systematic study of the elution of magnesium and calcium from
Dowex 50 X 8 resin using α-hydroxyisobutyric acid (α-HIBA) at
various pH values and concentrations, indicated that the difference in
the equilibrium distribution coefficients of these two elements was
large enough for a good separation. This fact was applied...
A comparison was made of the d.c. conductivity of KCI:Pb²⁺
and KCl:PbO single crystals at temperatures greater than 325°C.
The energy of activation was 0.72 ev for all crystals. Lead concentration
was determined by chemical, optical and electrical methods. The
half band width of the UV absorption band at 273...
Six polycyclic aliphatic hydrocarbons were reacted with the
trichloromethyl radical photolytically generated from bromotrichloromethane
at 40°. Relative rates of reaction were correlated
with a computer analysis of the change in strain energy in going
from the ground state to the intermediate. A good correlation between
the log of the relative...
Part 1
The pyrolysis of cis-1-trimethylsiloxy-1-cyclopr opyl-3-cyclononene in the temperature range 285-350° is described. Instead
of siloxy-Cope rearrangement, undesired desiloxylation took place.
Part 2
Gas-phase pyrolytic rearrangement of 2-phenyl-1-trimethylsiloxy-1-vinylcyclononane was investigated in a static system
in the temperature range 213-330°. It was discovered that
three major products resulted: cis- and...
Major and minor minerals have been separated from
three L-6 chondritic meteorites (Alfianello, Colby (Wisconsin),
and Leedey). Olivine, hypersthene, diopside, feldspar,
troilite, chromite, phosphate minerals, and metallic
minerals were analyzed for major, minor and trace elements
using instrumental neutron activation analysis and radiochemical
neutron activation analysis techniques. Concentrations
df the...
The investigation
of impurity effects on the properties of alkali
halide crystals has often been difficult because of the variation of procedures used in various experiments.
The purpose of this work is to
develop a self consistent method of measuring the IV dipole polarization properties of single crystals while eliminating...
Ninety basalt samples from eight locations in central Oregon
and one location in the Willamette Valley were analyzed for Si and Al.
Fourteen basaltic rock specimens (> 1 kg each) from four buttes in the
Willamette Valley were sampled and analyzed for Si, Al, Fe, Na, K,
Mn, Cr, Co,...
A double-beam photometer was designed and built employing photon counting to give a direct digital readout. It was evaluated as an analytical instrument with special emphasis on pulse recovery time, pulse interaction and instrument settings. An equation is developed to explain pulse interaction in event counting systems.
The reaction between 4- chloro- 6- methoxy- 5-nitropyrimidine
and methylamine was investigated. The reaction product was identified
as 4-methoxy-6-methylamino-5-nitropyrimidine from synthesis
of the product via 4-chloro-6-methylamino-5-nitropyrimidine.
The product was the result of displacement of chloro substituent with methylamine. The reaction occured under mild condition (e. g. 15-20
C. in dioxane)....
Both oxy-Cope and siloxy-Cope rearrangements involve
(1, 3) and (3, 3) sigrnatropic shifts. Both the concerted mechanism,
and the stepwise mechanism via a diradical intermediate are possible.
In a cyclic system such as cis-l-vinylcyclooct-3-en-l-ol, the thermal
rearrangement takes place preferably through a diradical intermediate.
At high temperature, the reaction also...
The abundances of 12 elements, Fe, A1, Na, Ni, Cr, Mn,
Co, Ca, Sc, Ir, Sm and Eu have been determined by INAA in 61
individual chondrules (0.1-100 mg) separated from five Allende (C3)
meteoritic fragments ( 25g). Ti and V have been determined in 18
of these chondrules, and...
The relative rates of hydrogen abstraction from o-xylene,
o-diethylbenzene and a series of four benzocycloalkenes by trichloromethyl
radical were determined at 70°. The strain energies of the
hydrocarbons and the corresponding radicals were calculated. A good
correlation between the log of the relative rates and the calculated
changes in strain...
The relative rates of hydrogen abstraction from 1-phenylalkanes and a,w-diphenylalkanes using N-bromosuccinimide and bromotrichloromethane were determined at 70°C. In both cases the reactions were photoinitiated. Only benzylic bromination was observed. The 1-phenylalkanes reacted with both reagents to give rates largely independent of substrate. Similarly, the rate of the reaction between...
Part I
The pyrolysis of cis- and trans- 1, 2-divinyl-1- trimethylsiloxy -
cyclohexane, II- and III-TMS, under the same conditions as the
pyrolysis of cis-l-vinyl -1-trimethylsiloxycyclooct-3-ene, I-TMS,
confirms that a sequence of concerted reactions for the rearrangement
of II- and III-TMS to trans-l-trimethylsiloxycyclodec-3-ene,
IV-TMS, is a viable pathway in the...
This paper describes the synthesis of t-butyl bicyclo[7.1.0]
decane-2-percarboxylate and its photolytic decomposition. The title
compound was found to undergo simple homolytic cleavage when exposed
to light of 2537 A; producing the cyclodecyl radical, carbon dioxide,
and t-butoxy radical. The largest percentage of products arose from
an intimate radical pair...
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 reactions of cyclodeca-1, 2, 5, 8-tetraene with mercuric salts
in solvents of varying nucleophilicity are described. Instead of forming
the usual oxymercuration products reported for reactions of olefins
and allenes with mercuric salts, the major products obtained in the
present cases result from the initial electrophilic addition of the...
Sequential alkylation of Hagemann's ester with methyl and
methallyl halides has been studied. Treatment of Hagemann's ester
with methyl iodide and sodium ethoxide gave a mixture of 21 and 25
in a ratio of 4:1. Alkylation of 21 with methallyl chloride and potassium
t-butoxide afforded a mixture of 37 and...
The infrared absorption spectra (40-800 cm⁻¹) of the trifluorides
of Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Tb, Ho, Er, Tm, and Yb isolated
in solid argon, krypton and nitrogen matrices have been obtained. For
PrF₃ the symmetric and asymmetric stretching modes were observed;
PrF₃ is accordingly assigned a...
A long path dc plasma arc operated in an atmosphere of
argon is described. The arc is easily ignited and operated, and
is inexpensive to use. Samples were introduced into the arc as
solution aerosols. Radially resolved emission measurements are
reported for calcium, copper, and hafnium. The detection limit
for...
The atmospheric trace element abundances associated with
several major sources of air pollution in Western Oregon, such as the
paper industry, the metallurgical processing industry, the plywood
industry and agricultural field burning have been measured by instrumental
neutron activation analysis (INAA). Air samples were collected
directly from industrial stacks and...
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...
The design and construction of a chemiluminescence
photometer is described. The design is based on a discrete
sample system which has a number of advantages over
the previously described flow cell system and centrifugal
analyzer. The advantages include simple and inexpensive
equipment, small sample size, versatile electronic readout
system, and...
A new x-ray source capable of operating at up to 80
watts has been designed and developed, and put to use with
the Oregon State University Cylindrical Electrostatic
Analyzer. The new source produces over four times the
photoelectron intensity of its predecessor, from gaseous
samples, and accommodates a wider selection...
The application of lucigenin chemiluminescence for the determination
of trace concentrations of Co(II) is described. This method
is based on the enhancing effect that Co(II) has on the reaction of
lucigenin and hydrogen peroxide in a basic solution. The chemiluminescence
signal from a Co(II) enhanced lucigenin reaction, which is in...
The core-electron ionization potentials for mono- and
di(trifluoromethyl)benzene, for chlorofluoromethanes and for
chlorine have been measured in order to give information on
the electron distribution in these molecules and to investigate
differences between the inductive effect of fluorine
and that of CF3. For trifluoromethylbenzene the measured
ionization potentials in eV...
The thermolysis of trans-1 -trimethylsiloxy- 1-vinylcyclotridec-
3-ene (VI-OTMS) led to the formation of two major products: 4-vinylcyclotridecanone
(VII) and cyclopentadec-5-en-l-one (VIII) after
hydrolysis. Ketone VII is produced by a concerted [3, 3] sigmatropic
shift, while ketone VIII is formed by a [1, 3] sigmatropic shift with
a concerted or diradical...
A spectrophotometric study has been made of catalysis of the decomposition of sulfuryl chloride in carbon tetrachloride solution to an equilibrium mixture of sulfuryl chloride, sulfur dioxide and chlorine. The catalysts were activated charcoal, acetonitrile and 18-crown-6 polyether. A weak acetonitrile-sulfur dioxide complex also was established; formation constants found at...
The study of diffusion coefficients of n-alkanes and other organic compounds in silicones is undertaken by gas-liquid chromatography. About 0. 3% of stationary phase is coated on glass bead support so that the only significant source of peak spreading is due to slow liquid phase mass transfer. Diffusion coefficients are...
A critical study of the cold vapor atomic absorption and fluorescence instrumentation for the analysis of mercury is described. Some of the important modifications involve the reduction vessel, absorption cell, fluorescence cell, and radiation source. The new modified systems have much greater calibration sensitivities and lower detection limits than those...
The simultaneous diffusion of Ca 2+ and Sr 2+ ions in purified
single crystals of KC1 and NaC1 was studied over the temperature
ranges from 451°C to 669°C in KC1 and from 448°C to 683°C in NaCl.
A radioactive tracer technique was used in two types of measurements:
diffusion from...