To determine whether or not the (n,2n) reaction in Be would produce a net increase in fission neutrons in a power plant, the distribution of In resonance neutrons slowed down from fission energies in a graphite block was measured with and without a 2" of Be in front of a U3O8 slab undergoing fission. The thermal neutrons producing the fissions were obtained by slowing down neutrons from a cyclotron source. The observed distribution without Be was well represented by a Gaussian source range 36 cm. (corresponding to an initial fission energy of 3 MeV) and a similar sink of range 7.8 cm. The total In resonance intensity with Be was 5% less than without Be. On the assumption that the effect of the Be is entirely due to its different mean free path and moderating power, the In distribution with Be was calculated. Since the m.f.p. as a function of energy is not known for Be, two separate calculations were made using the highest (2.9 cm.) and the lowest (1.80 cm.) possible values for the effective Be m.f.p. Both calculated curves were found to be higher than the observed Be distribution, indicating that at least 10% of the fission neutrons …

The following document describes the analysis on an attempt at separating mercury isotopes by making their environments as widely different as possible.

Report issued by the Bureau of Mines over diesel engine operations. As stated in the introduction, "it is the purpose of this report to present such data and to reemphasize the importance of adequate maintenance for diesel engines used underground" (p. 2). This report includes tables, and illustrations.

Report and corollary maps on the Coyote Mesa District, Dolores Plateau Area, Colorado

Report issued by the U.S. Bureau of Mines on the investigative and educational work done by the Safety Division during 1942. Accident prevention methods and safety incentives are presented. These include first-aid and mine rescue training programs. This report includes tables, and photographs.

Introduction: Vanadium ore is being mined at many places in western Colorado, southeastern Utah, northeastern Arizona, and northwestern New Mexico (fig. 1). Eight mills in this region produced about 4,300,000 pounds of V2 05 in 1942, representing about 90 percent of the vanadium obtained from domestic sources. Although ore production has mostly exceeded mill capacity since 1937, production during the last half of 1942 averaged only about 19,000 tons or ore a month, whereas the capacity of these mills total about 22,000 tons a month. At the expected rate of ore production, ore stockpiles will be exhausted sometime in 1944, and these mills will then have excess capacity. With more intensive prospecting than now practiced, however, it is believed that sufficient reserves can be indicated to sustain capacity operation of these mills for several years. This memorandum is prepared to specify those areas that are considered most favorable from a geologic standpoint for developing large reserves of vanadium ore by prospecting. It is based on intensive studies by the Geological Survey since 1939 in most of the areas that produce vanadium ore.

The following report was written to replace previous directions submitted in the February 6, 1943 report on the preparation of the solution X(OC₂H₅)₅.

The resonance absorption of uranium for neutrons has been investigated between 20 degree C and 1000 degree C. Experiments were caried out on both UO2, density 4.63, and metal. The resonance activity was measured with respect to that of an iodine monitor at several different temperatures and the ratio of activity at temperature T to that at 20 degree C was determined. The increase in activity is 0.9 per cent per 100 degree C for the oxide and 1.1 percent per 100 degree C for the metal. The period of U239 was found to be 23.54 +- 0.05 min.

Report issued by the U.S. Bureau of Mines on the characteristics of different coal varieties after carbonization. The properties of these different coals are presented. This report includes tables, and photographs.

Report issued by the U.S. Bureau of Mines discussing fatalities of mine workers while wearing self-contained oxygen breathing apparatuses. Descriptions of the circumstances surrounding the deaths of 26 workers are presented. This report includes a table.

Technical report covering (1) analysis of uranium bromide and chloride samples, (2) the ferric-nitrate method of analyzing uranium fluorides for fluorine, (3) spectrographic determination of boron, cadmium and manganese in magnesium metal, (4) service analyses. contributions to other problems, (5) attempted preparation of uranous oxyfluoride, and (6) corrections in previous reports.

Calculations were made to determine the temperature at various points of a thick disc and cap, on the assumptions that the heat production rate is uniform throughout the slug and that the slug is in perfect thermal contact with the cap. Results obtained by different methods of computation are compared with each other and with results obtained by Drew on the Paschkis electrical network computer at Columbia University.

The present report is concerned with the electronic relay which, upon the reaching of a pre-determined value of ionization current in the associated chamber, actuates the safety rod release mechanism. The are here proposed two independent suggestions: (1) An improved trip circuit of such sensitivity and stability as to allow it to be actuated by a signal directly from the chamber without the necessity of interposing intermediate amplifier stages. The value of chamber current at which tripping occurs is stable to +- 0.4%. (2) A triple-wound relay to prevent shut-downs of the pile which would otherwise be caused by development of defects in the safety circuits.

The resonance absorption of a lump is described in terms of three components. Calculations of resonance absorption are carried out using the model for the resonance spectrum of uranium recently derived; calculations are also made with variations of this model which involve local fluctuations in level strengths. For metal and oxide lumps the agreement with observation is satisfactory. For dilute mixtures, whose resonance activation was measured by Mitchell, computed values fall 20% to 30% above measured ones.

The transition region between two parts of a pile which have different compositions is investigated. In the case where the moderator is the same in both parts of the pile, it is found that the diffusion constant times thermal neutron density plus diffusion constant times fast neutron density satisfied the use pile equations everywhere, right to the boundary. More complicated formulae apply in a more general case.

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.

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.

The following report is the third in the Geological Survey's series discussing rare or uncommon elements and possible sources. The element discussed in this report is indium, found abundantly in sphalerites.

Abstract. Measurements were made to determine the effect of thermal cycling on heat transfer from slug to jack using a slug with a sand blasted surface. The value of the transfer coefficient h decreased from initial values ranging from 10 to [formula], to values and [formula] after 1700 cycles, and to a range of 0.15 to 0.45 [formula] after 3200 cycles. Comparisons are made with the results found for slugs with different surfaces.

Abstract. In order to anticipate radiation - chemical effects in solutions of active lanthanum, various solutions and suspensions containing lanthanum were irradiated with an electron beam. Separation of lanthanum from barium by the alcoholic HCl method is not rendered less efficient by radiation, although considerable gas evolution occurs. Suspensions of lanthanum as hydroxide and as ferrocyanide are not appreciably solubilized by radiation. Lanthanum oxalate is decomposed by radiation, is partially thrown into solution, and finally dissolves completely when all the excess oxalate ion in the solution has been destroyed.

Abstract. the fluctuation in pile intensity caused by an oscillating point absorber is calculation. It is found that the nature of the response depends on the frequency of the impressed oscillation. If the frequency is high compared to the decay rate of the high harmonics, the response consists of a wave which is propagated away from the oscillator. If the frequency is low, the propagated wave character of the response disappears and the intensity of the whole pile tends to oscillate with the same phase. The amplitude of the response decreases with increasing frequency.

The solubility constants are presented for He , Kr , Xe , O2 , N2 , and air in H20 . Inter-diffusion constants for gases and the diffusion of gases in water are given.

Abstract. Irradiated Whiting graphite possesses a small negative or a positive Hall constant, depending upon the dosage. Annealing at 500 degrees C for 1 hour in helium results in a Hall constant which is large in magnitude and negative in sign. The properties of the annealed graphite are presumably close to those of the original unirradiated material. Unirradiated AGOT-K graphite has a large, negative Hall constant. A mechanism is suggested which accounts for the change in sign of the Hall constant as a result of neutron bombardment.

A report regarding the San Miguel River District, San Miguel Plateau Area, colorado.