Procedures were developed for fabricating highperformance radiators and heat exchangers for the Aircraft Nuclear Propulsion (ANP) Program. These components, which contain multitudes of tube-to-tube sheet and tube-to-fin joints, are similar in design to those under consideration for a variety of space vehicle applications. In order to ensure reliability of the tube-to-tube sheet joints, techniques producing welds of extremely high quality were used and back brazing of the welds with a suitable alloy was incorporated. High-temperature brazing was also incorporated to attach high-conductivity fins to Inconel tubes in the radiators. The selection of a suitable brazing alloy for these applications was dependent upon several factors, including corrosion and oxidation resistance, flow point, and mechanical properties. A Ni- Si-B alloy was found to be adequate from all these considerations. Special brazing procedures were developed to obtain satisfactory flowability of this brazing alloy on tube-to-fin joints. The suitability of these fabrication procedures for the very stringent service conditions to which the radiators and heat exchangers were subjected was demonstrated by testing full-size components under operating conditions. (auth)

The objectives of the SNAP 7A program were to design, manufacture, test, and deliver a five-watt electric generation system for a U. S. Coast Guard 8 x 26E light buoy. The 10-watt Sr/sup 90/ thermoelectric generator, the d-c-to-d-c converter, batteries and the method of installation in the light buoy are describcd. The SNAP 7A generator was fueled with four capsules containing a total of 40,800 curies of Sr/sup 90/ titanate. After fueling and testing, the SNAP 7A electric generating system was installed in the Coast Guard light buoy at Baltimore, Maryland, on December 15, 1961. Operation of the buoy lamp is continuous. (auth)

Progress is reported on investigations in support of the Experimental Gas-Cooled Reactor, the Pebble-Bed Reactor Experiment, Advanced reactor design and development, test facilities, components, and materials. Topics covered include EGCR physics, EGCR performance analyses, structural investigations, EGCR component and materials development and testing, EGCR experimental facilities, PBRE physics and design studies, fueled-graphite investigations, clad fuel development, design studies of advanced power plants, experimental investigations of heat transfer and fluid flow, development of equipment anmd test facilities. and fabrication studies. (M.C.G.)

Six groups of U-2 wt% Zr fuel slugs were irradiated in the first core of the EBR-I to burnups of 0.080 to 0.189 at.% at calculated temperatures of 307 to 353 deg C. Two groups of cast specimens were found to be more dimensionally stable than four groups of wrought slugs. Of the wrought slungs, the as quenched group showed less tendency to grow than the three groups which had some annealing after quenching. Specimens at burnups of about 0.189 at.% and at 383 deg C showed the onset of swelling as indicated by density measurements. The hardnesses of these specimens seemed but little affected by radiation, but there was an indication of softening with increasing irradiation temperature. (auth)

Results of the examinations of corrosion specimens exposed in the HRT are presented. Specimens examined include core screen samples, core specimen array No. 1, blanket specimen array No. 2, core solution line specimen arrays No. 103 and 103A, and blanket solution line specimen array No. 203. These data include corrosion rates, computed from specimen weight-changes, and results of chemical analyses of scales removed from the specimens or specimen holders. A summary is included of the HRT operating schedule during exposure of the specimens and of the status of examinations for the specimens removed from the reactor prior to run 20. (auth)

The loading operation for SM-1 Core II is described. Results of startup physics measurements (Test A-300 (Series) and fission product iodine monitoring in the primary coolant are given. The SM-1 Core II initial loading progressed satisfactorily, fulfilling the predictions of the zero power experiment performed at the Alco Criticality Facility. The initial cold clean five rod bank position was 6.53 in.; the initial hot, no xenon, five rod bank position was 9.62 in.; the initial hot, equilibrium xenon, five rod bank position was 11.41 in.; and the initial hot, peak xenon, five rod bank position was 12.14 in. Rods A and B were 19.00 in. in all four measurements. Stuck rod measurements indicated that an adequate shutdown margin was available with 20% of the rods fully withdrawn. All rod calibrations indicated a distinct shift and broadening of the peaks when compared with similar Core I calibrations. The temperature coefficient for Core II was 3.5 cents/ deg F at 440 deg F. Equilibrium xenon was worth approximately - 00 while peak xenon was worth - 43, both relative to the hot, no xenon core condition. During the period June 2, 1961 through September 30, 1961, the reactor operated at a total …

ABS> The removal rates of iron, nickel, and chromium from synthetic stainless steel waste solutions during electrolysis over a mercury cathode were studied. The loading capacity of the mercury for the stainless steel metals was estimated on the basis of laboratory experiments to be about two% by weight. The laboratory data indicated that, at an electrode potential of --1.80 voits vs S.C.E., 85 ampere-hours per liter of waste removed essentially all of the stainless steel ions from a sulfuric acid solution containing 0.13M metal ions at 35 deg C. (auth)

The status of the analytic portion of the KEWB program at the time of completion of the spherical core experiments is summarized. Three computer programs were developed for use in this analytic effort. The first reassembles and smooths three decades of reactor power data read separately from oscillogram records of reactor excursions. It then computes the logarithmic derivative of the power, energy release, fuel solution temperature, and temperature compensated reactivity. The second program utilizes the space-independent neutron kinetics equations with any number of delayed neutron groups to determine the reactivity in the reactor from the power and its derivative. The third program solves the space-independent kinetics equations for the neutron flux from an input reactivity or initial period. Up to 50 reactivity feedback equations includirg delayed neutrons are provided for in this program. A mathematical model of the reactor investigated extensively was one containing six delayed neutron groups, conventional treatment of temperature reactivity compensation, and void compensation of reactivity induced by radiolytic gas void growth proportional to the product of reactor power and energy release. Partial mathematical solutions to the kinetic equations were derived for reactivity feedback proportional to prompt temperature and void growth according to the product of power …

Discussion is given on the welding fabrication of tungsten, molybdenum, niobium, and tantalum. Properties which make the four refractory metals important are tabulatcd along with titanium which is given for comparison. Extensive evaluation was conducted using the gas, tungsten arc welding process employing both manual and machine welding. Design data were obtained exclusively from machine welded sheet materials. Flash welding, resistance spot welding and brazing, electron beam welding, and high frequency resistance welding processes were also applied to molybdenum alloys. The oxidation of molybdenum, tantalum, and niobium in flowing air at 2000 deg F is also given. (P.C.H.)

EQUIPOISE-3 is an IBM-7090 FORTRAN programmed code for the solution of two-group, two-dimensional, neutron diffusion equations. A maximum of 2l00 mesh points may be used, and the code will solve problems in either rectangular or cylindrical geometry. Logarithmic derivative boundary conditions are allowed, and removal of neutrons from both groups is permitted. Adjoint fluxes with the associated fluxadjoint flux regional integrals may be calculated automatically if desired. A constant buckling, group-dependent buckling, or region-dependent buckling may be specified for rectangular geometry. This program is intended to fill the need for a rapid two-dimensional calculation suitable for survey calculations. During the iterative part of the computations, all operations are carried out in the core memory. The magnetic tape memory is used only for input, output, and program storage. The running time for a 1000-point problem requiring 100 iterations would be about 3 min.(auth)

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The distorted-wave theory of direct nuclear reactions is presented in a unified manner, in which the effects of assuming various reaction mechanisms and nuclear models appear only in certain radial form factors. The zero-range approximation is used, and spin-orbit coupling is neglected in the distorted waves. Formulas are given for transition amplitudes, cross sections, and polarizations. A description is given of the IBM-704 computer code SALLY that is based on these formulas. (auth)

Geologic lnformation required to define the pre- and post-shot physical and chemical characteristics of the sait and other rocks affected by the exploslon was gathered. Information on the pre- and post-shot hydrologic condltlons at the site and the surrounding area was also obtalned. (M.C.G.)

The calculation of destructive nuclear bursts in fast reactors by an improved Bethe-Tait method, which, for purposes of calculation, neglects propagation of the pressure wave is described. TMen exact numerical calculations for hydrodynamic and neutronic conditions during the power burst are performed in order to assess the importance of this neglect. (auth)

The NIGHTMARE program calculates the gamma-dose rate at any point in or near a reactor by means of the NDA buildup-factor method. The source distributton is obtained from a two-group, two-dimensional diffusion code (EQUIPOISE-2). Seven gamma-energy groups are used. As many as nine different concentric cylindrical regions may be considered, but only radial variation of attenuation and buildup properties is permdtted. Two schemes of estimating buildup factors through a succession of materials are built into the code, and results may be obtained by using either or both methods. An IBM 7090 computer wtth seven tape untts is required. Computations are performed at the approximate rate of l0,000/n mesh points per minute, where n is the number of axial, radial, and angular increments. The program is run under the control of the IBM 7090 MONITOR system. (auth)

The effect of polarizing mngnetic field intensity on the nuclear resonant absorption was studied by varying the field strength at a 1-mc Co/sup 57/ source from 0 to 1000 gauss while keeping the absorber between the poles of a magnet having a fixed field of 800 gauss. The rates of resonance absorption change with field intensity were greatest in the region of 300 to 1000 gauss, and the% nuclear resonant absorption for 1000-gauss fields was 8.5 and 26% for perpendicular and parallel fields, respectively, as compared with 15% for no fields. Other absorption measurements for Co/sup 57/ sources are also reported. Calculations on the use of nuclear resonant absorption to measure gravitational fields and altitudes were made which indicates that this application is not promising. (D.L.C.)

A total of 455 mlce, rats, gulnea plgs, and rabbits was subjected to lmpact at velocitles ranglng between 25 ft/sec and 51 ft/sec. The deslred velocities were generated by allowlng the anlmals to free-fall from various helghts to a flat concrete pad. The ventral surface of each anlmal was the area of impact. Problt analyses of the 24-hr mortallty data ylelded LD/sub 50/ lmpact veloclties with 95% confldence limits as follows: mouse, 39.4 (37.4 to 42.0) ft/ sec; rat, ft/sec; and rabbit, 31.7 (30.2 to 33.3) ft/sec. The LD/sub 50/ figures for the mouse and rat were slgnificantly higher, statlstically, than those for the gulnea plg and rabblt. The small spread ln the LD/sub 50/ values suggested little variation ln the tolerance of blologlcal systems to impact. Further, the steepness of the mortallty curves lndicated a narrow survlval range to lmpact. Extrapolatlon of the experimental data to the 70 kg anlmal yielded a predicted LD/ sub 50/ impact velocity of 26 ft/sec (18 mph). Literature relevant to the human case was revlewed and the tentative appllcabllity of the predlcted flgures to adult man ls discussed. (auth)

The rapid dissolution of uranium dioxide is described, wherein copper is added to molten lead chloride at 550 deg C. and chlorine is passed through the melt. The integral dissolution of zirconium-clad uranium dioxide fuels is also described. The dissolution rate of uranium dioxide is directly proportional to the concentration of cuprous chloride if an excess of chlorine is used; the value for the rate constant is approximately 100 mg (UO/sub 2/) cm/sup -2/ min/sup -1/ (CuCl molality). The uranium dioxide is converted to water soluble uranyl chloride. The dissolution rate can be controlled by three factors: the copper concentration, the flow rate of chlorine, and the surface area of uranium dioxide. Scoping work indicates that iron chloride may be as effective catalytically as copper chloride for uranium dioxide dissolution in the lead chloride -chlorine system at 550 deg C; thallium chloride is not as effective. (auth)

A mathematical analysis is presented concerning the performance of the radial or vane type steam separator. The analyses are concerned with the spread of flow on the vanes because of centrifugal force (which requires that the vane height be greater than the nozzle), and with separation of the vapor from the liquid. (J.R.D.)

The report comprises seven sections. A separate abstract was prepared for each section. (J.R.D.)

Revisions in the reactor system and operating procedures necessary for carrying out a proposed dry critical experiment in the EBR-II are described. The safety aspect of the program is considered. The critical experiment will be conducted in the EBR-II prior to filling the primary system with sodium. The facility, experimental program, operational and experimental procedures, and hazards and plant safety are described. (M.C.G.)

Recent work on isotopic x ray sources is reportcd. The research was directed toward optimization of high-level isotopic sources and evaluation of their use in typical scientific and technical applications. The resulting experi- mental data are used in obtaining an approximate mathematical formulation of x- ray output as a function of beta energy, target mnaterial, and source configuration. (J.R.D.)

A dry criticality test was carried out to determine the minimum critical mass of the HNPF Core without sodium. A subcritical calibration of the central control rod was performed and the relative reactivity worths of the inner ring of six control rods were determined. The extrapolated critical loading for the various plots after each incremental fuel loading with all rods out is shown. A tabulation is presented of multiplication data taken throughout the dry critical test. In order to find the relative integral reactivity worth of the central control rod in the dry critical loading, subcrltical multiplication data were obtained. The test completion criteria as stated in the test procedure were met. (M.C.G.)

Gaseous waste handling systems are compared for direct and indirect boiling water and pressurized water reactors for PL-3 application. Areas that are common to the various concepts are not discussed since they do not enter into a comparison study. The major differences present are in the handling of active gases released to or held in the primary system coolant. These gases which could be present, their possibIe release from the system, and the necessary processing requirements are discussed in detail. Sufficient information is presented to enable one to analyze the methcds required to remove gaseous activity present in other size and type pressurized and boiIing water reactors. (auth)