The four types of respirator cartridges used at the 202 S Building were tested against aerosols found at that location, and in the laboratory against non-radioactive gaseous ruthenium tetroxide. Positive penetration of two types of cartridges was shown with one process aerosol. Gaseous ruthenium tetroxide penetrated all types of cartridges tested. Leaks were found in some of the cartridges. Particle size of aerosol particles was measured by means of cascade impactor samples and electron photomicrographs. A high percentage of the aerosol particles was found to be less than 0.2 microns in diameter. Ru¹⁰³ + Ru¹⁰⁶ and Zr⁹⁵ + Nb⁹⁵ were shown to be present in the process aerosol by gamma ray spectrometer analysis. Possible causes of penetration of respiratory equipment by ruthenium are discussed and suggestions made for alleviating the problem.

"Progress is reported on Phase II of a program for the development of a mixed fission product fueled thermoelectric generator. Materials studies are described in which bonded assemblies of bismuth telluride were life tested up to 3000 hours at 350 to 400 deg F hot junction temperature. Data were too inconsistent to define any satisfactory long-life bonding process. Further work is needed to eliminate the process variables. Insulation studies aimed at determining the thermal conductivity of various insulations with different fill gases under reduced pressures are described. Opacified aerogel powder appears to be very promising as an insulation medium for a diffuse heat source. A full- scale simulated test generator aimed at proving out the concept of a diffuse heat source for power generation is described. Progress on the construction of this electrically heated generator and its thermoelectric power converter is related.

Abstract. A particle ionization chamber of sensitivity sufficient to detect a source of one neutron per second has been used to measure the neutron yield from a thick target of sulfur upon bombardment with polonium alpha particles. The high-geometry boron trifluoride chamber used had an efficiency of 1.9 percent for fission neutrons. The neutron yield from a thick target of sulfur was measured by this instrument and found to be .0035 +- .0013 neutrons per million incident polonium alpha particles.

An attempt is made to estimate the influence of operation upon the mechanical properties of tubealloy. It is to be emphasized that the work is highly speculative, being base upon a set of judicious assumptions regarding the transport material within the metal and should not be used as a substitute for a set of well-planned experiments. The two principal effects considered are the hardening which results from the atomic displacement produced by the fission fragments and the changes in mechanical properties arising from the presence of the fission products. The principal conclusion to be drawn is that the disruption of the metal which accompanies operation takes place at at sufficiently high rate that it could readily cause serious changes in the mechanical properties of the slups. the reversal of the disruption resulting from thermal effects probably is sufficiently high to prevent serious embrittlement as a consequence of displacement through most of the volume of the slug if not at the surface. On the other hand, the migration of atoms also appears to be sufficiently high that the rare gas products may have time to diffuse to cracks and produce embrittlement.

Summary. At the time this project was initiated, all brazing had been confined to small retorts of ten cubic feet capacity or less. Larger assemblies were scheduled which required retorts of over 100 cubic feet capacity. Hydrogen atmospheres had given the best results, however, there was considerable reluctance to use hydrogen in these large retorts from a safety standpoint. It was thought that thru the use of PMC 2252, an argon - 2 1/2% hydrogen gas atmosphere which in non-explosive, sufficient cleaning action might be attoined without the inherent hazards encountered with hydrogen. An investigation of the argon - 2 1/2% hydrogen gas as a brazing atomosphoer

Technical report abstract: Since UNH is a highly dissociated compound which ionizes to NO3 and (UO2), the latter ion being very weakly basic, a solution of pure UNH is quite acid (pH about 3). It is possible to titrate to a phenolphthalein and point with standard caustic solution and obtain a figure which represents the free acid plus the NO3 from the the UNH. However, titration of the free nitric acid alone in such a solution presents quite a problem. By precipitating and removing uranium from solution by means of potassium ferrocyanide, the residual free acid may be titrated directly by means of standard caustic using either methyl red or phenolphthalein indicators, with an error of less than 4%. A method is given to determine formic acid, should that acid be present in the mixture.

Abstract. The precipitation of Pa233 with MnO2 from a solution of thorium nitrate has been studied in some detail and seems quite satisfactory up to 36 gm Th(HO3)4 4H2O per 100 cc solution. The concentration of Pa233 with respect to the manganese dioxide carrier and the thorium precipitated with the carrier appears to be accomplished quite well by either a series of MnO2 cycles or thorium iodate cycles. Volatility methods for both the separation of Pa233 from the original thorium and for its separation from MnO2 are now under investigation. It has been decided that thorium carbonate will the the thorium compound used in the pile at Site X.

This report deals with the (1.1) physical properties of graphite, (1.2) effects of pile irradiation on the properties of graphite, (1.3) effect of irradiation on "ceramic" materials, (1.4) effects of radiation on ice -- the x-ray induced luminescence of ice, (1.5) investigation of color centers and other optical properties of single crystals. (2.1) radiation chemistry of liquids, (2.2) application of mass spectrometry to chemical problems, (2.3) vapor pressure and heat of vaporization of uranium, (3.1) nuclear properties of Zr93 and Nb93m from fission, (3.2) mass distribution in the spontaneous fission of Cm242, (3.3) Upper limit to the lifetimes of the first excited states of Th236, U234, and Pu236, (3.4) on the one-body model of alpha radioactivity, (4.1) spectrographic analysis, (4.2) chemical analysis, (5.1) paramagnetic resonance measurements, and (5.2) the 60-inch cyclotron.

This report deals with the (1.1) physical properties of graphite, (1.2) effects of pile irradiation on the properties of graphite, (1.3) effect of irradiation on "ceramic" materials, (1.4) effects of radiation on ice -- the x-ray induced luminescence of ice, (1.5) investigation of color centers and other optical properties of single crystals. (2.1) radiation chemistry of liquids, (2.2) application of mass spectrometry to chemical problems, (2.3) vapor pressure and heat of vaporization of uranium, (3.1) nuclear properties of Zr93 and Nb93m from fission, (3.2) mass distribution in the spontaneous fission of Cm242, (3.3) Upper limit to the lifetimes of the first excited states of Th236, U234, and Pu236, (3.4) on the one-body model of alpha radioactivity, (4.1) spectrographic analysis, (4.2) chemical analysis, (5.1) paramagnetic resonance measurements, and (5.2) the 60-inch cyclotron.

The report summarizes results obtained since September, 1951, by total neutron yield experiments using 190 Mev deuterons and the MnSo4 tank method (UCRL-1375 and UCRL-1480). A new method of beam monitoring has resulted in establishing firmly the absolute yield for solid uranium and thorium primary targets backed by a solid uranium secondary. The beam monitoring was done by using a primary target built into a faraday cup. This method circumvents errors caused by recombination in the ionization chambers used previously.

From Abstract : "The solubilities of the individual rare earth lactates and α-hysroxyisobutyrates in water at 20 and 60° were determined for comparison with the rare earth glycolate solubilities determined earlier."

Technical report. From Abstract : "The reactions of VCl2. VCl3, and VCl3-VBr3 mixtures with bromine vapor at 350 to 450°C led to vaporization of the halides and deposition of mixed halides of vanadium (III) at lower temperatures."

Technical report. From Abstract : "The thallium-rich region of the thallium-indium phase diagram was determined from atmospheric pressure to 5.5 kbars primary from electrical resistivity data obtained as a function of composition, temperature, and pressure."

In H measurements, the measured flux-linkage change represents twice the value of H to be plotted. In B measurements the bucking coil links flux equal to the air-flux in the B-measuring coils. The measured flux change therefore corresponds to twice the flux of intrinsic magnetization in the sample.

In regard to the production of ozone and various nitrogen oxides in air by action of x-rays or gamma rays, thre seems to be no direct experimental data which can be used. There is some data on the action of alpha particles on air and some on the action of cathode rays.

From introductory paragraph: "This is the first quarterly report of the Biology Division of the Argonne National Laboratory. During the three-month period covered by this report, a large share of the time of many investigators has been spent in collating work done under the Biology Section of the Metallurgical laboratory for publication in the Plutonium Project Record. The large amount of work done under wartime pressure has made this, as in other divisions and projects, an important part of the transition to the post-war period."

From abstract: "Iron(III) can be separated from many elements by extraction from 6 to ͟8M hydrochloric acid. The extraction is carried out by passing the aqueous hydrochloric acid solution through a column packed with 2-octanone adsorbed onto a poly-fluorocarbon resin. Fluoride, phosphate, sulfate or citrate cause no interference. Traces if iron(III) can be separated quantitatively from large amounts of copper(II) or zinc(II); traces of titanium(IV) can be separated from large amounts of iron(III)."

From abstract: "A study has been made of the yields of gaseous products labeled with C11 from the C12(γ, n) reaction in liquid cyclohexane. The effects of variations in the radiation dose and in the concentration of dissolved iodine during irradiation on the yields of these products were studied in order to elucidate the reaction mechanisms. A reaction model was developed as a method of assessing the relative importance of radical and molecular processes. The data suggest (1) that the formation of C11 labeled CH4, C2H4 + C2H6, and C3H6 involves a hot radical process while (2) the formation of C2H2 is by a molecular reaction with cyclohexane."

From abstract: "The first order correction in αZ to the Bethe-Maximon pair production cross section is calculated for the case where the incident photon and one of the electrons has an energy much greater than mc2. Comparison of these calculations to the experimental data of Plimpton and Hammer shows an improvement ina greement between theory and experiment of approximately a factor of 1+(αZ4π/15) for low positron kinetic energies. However, for positron kinetic energies of the order of 1 Mev no improvement is obtained."

From abstract: "The electrical resistivity of NaxWO3, LixWO3, and KxWO3 has been measured at 300°K. The range of x-values was 0.25 < x < 0.9. All resistivities were characteristic of a metal and lie on a single curve. An extrapolation of the conductivity curve to zero conductivity indicated that the tungsten bronzes should be semiconductors for x < 0.25. The resistivities that have been measured for tungsten bronzes with x < 0.25 showed semiconducting behavior. The resistivity of LixWO3 exhibited an anomalous peak in the ρ vs Τ cuve. The Hall coefficient of Li0.37WO3 indicated one free electron per alkali atom as was previously found for NaxWO3. The Seebeck coefficient of NaxWO3 depended linearly on x[superscript]-2/3 as expected from free electron theory. The implications of these and some other data are discussed."

From abstract: "The electronic spectra arising from the excitations of pi-electrons in homo-nuclear conjugated bond systems are calculated for 37 aromatic hydrocarbons. The theoretical approach used takes into account overlap effects between different a atoms, correlation between different electrons, variations in internuclear distances, and the influence of non-conjugated neighbors, hydrogen and carbon. Four types of approximations are carried trough for the molecules in order to obtain an estimate of the inadequacies of the theory. From the calculated transition energies and oscillator strengths, theoretical spectra are synthesized and compared with observed spectra. In order to help the interpretation, a decomposition of the transition dipoles into atomic contributions is introduced. The spectra of alternant molecules are succesfully predicted, but the limits of the underlying assumptions appear to be exceeded in the applications to non-alternant systems. The calculations are markedly successful for the peri-condensed systems, which had presented an obstacle to previous treatments. It is found that the calculated spectra are fairly sensitive to small variations in interatomic distances. calculations with exact atomic positions, where available, give considerably better agreement with experimental spectra. The calculations lead to an understanding of the general spectral pattern found in all aromatic hydrocarbons. On this basis the …

Technical report. From Abstract : "The equilibria (1) VBr3(s) = VBr2(s) + 1/2Br2(g) and (2) 2VBr3(s) = VBr2(s) + VBr4(g) were studied over the range 644 to 805°K by transpiration in helium."

Technical report. From Abstract : "The vapor pressures of crystalline VCl2, VBr2, VCl3 and VBr3 have been measured by the Knudsen effusion method using pyrex and Vycor effusion cells. ... During the measurements on VCl3 and VBr3 dissociation and disproportionation of the samples occurred simultaneously with the simple vaporization. However, because the product of each of these processes was collected separately during an experiment, the vapor pressure due to sublimation was obtained without difficulty."

From abstract: "Rats have been fed active strontium which was adsorbed on clay, while their controls were fed the same amount of active strontium in aqueous solution. There was no significant difference in the amount deposited in the skeleton between the two groups, and it is concluded that if ions are adsorbed on inert material, they will be eluted during their passage through the gastrointestinal tract."