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A Comparison of Some Characteristics and Attitudes of Self-Described Future Mothers versus Non-Mothers

Description: This study compared women with a highly positive interest in becoming mothers with women having little interest in having children,with respect to biographical data, childrearing attitudes, and personality characteristics. One hundred twenty-one undergraduate college women were administered a biographical questionnaire, the Parental Attitude Research Instrument, the Adjective Check List, and an attitude index designed to assess level of interest in having children. A statistical analysis revealed the remarkable similarity of the two groups of women, as the groups differed significantly in only two areas. Women with little interest in having children scored higher on the subscale Ascendancy of the Mother, and the women also differed in their view of the ideal situation for an adult woman.
Date: May 1975
Creator: Cofer, Jeanne
Partner: UNT Libraries

Application of a low energy x-ray spectrometer to analyses of suspended air particulate matter

Description: A semiconductor detector x-ray spectrometer has been constructed for the analysis of elements in air particulate specimens. The excitation radiation is provided, either directly or indirectly, using a low power (40 watts) Ag anode x- ray tube. Less than 100 ng for most of the elements in the range Mg $Yields$ Zr, Pb are easily detected within two 1-minute counting intervals. A calibration technique for light element analysis and an experimental method which compensates for particle size effects are discussed. (auth)
Date: September 12, 1975
Creator: Giauque, R.D.; Garrett, R.B.; Goda, L.Y.; Jaklevic, J.M. & Malone, D.F.
Partner: UNT Libraries Government Documents Department

Savannah River Laboratory monthly report: {sup 238}Pu fuel form processes

Description: Progress during August 1975 in the development of {sup 238}PuO{sub 2} heat sources is reported. In studies to characterize {sup 238}PuO{sub 2}, the following were concluded: particle size was determined to be the most important characteristic affecting the variation in fabricability of {sup 238}PuO{sub 2}; problem feed consists of smaller particles (2 to 4 {mu}m) than older, acceptable feed (4 to 6 {mu}m). The particle size of new feed has varied from 3 to 10 {mu}m primarily as a result of varying precipitation temperature; equations have been developed from statistically designed precipitation experiments that relate precipitation temperature, nitric acid concentration, and plutonium concentration. to particle size; characteristics of acceptable feed have been defined: a particle size mode of 4.5 to 6.0 $mu$m, with an agglomeration index of 20 to 50 wt percent, and 0 to 15 wt percent of fines (less than 2 $mu$m particles); precipitation temperature is the most important variable affecting particle size; and desired particle characteristics can be achieved by precipitating at 35 +- 5$sup 0$C, 1.2 +- 0.1M nitric acid, and 4 to 7 g/l plutonium in the feed solution. No deleterious effects from ultrasonic decontamination were observed on either fuel form simulants or the iridium containment shells. Helium release studies show that shards can be stored for over a year without producing microstructural damage in hot-pressed products. Temperature gradients of only 50$sup 0$C during shard seasoning can affect product quality. Presintering of cold-pressed pellets before breakup produces shards for the Milliwatt Radioisotopic Thermoelectric Generator Program (Milliwatt) with a minimum of fines. Fines content of these shards compares favorably with the fines associated with the Mound Laboratory hydroxide shards. (auth)
Date: August 1, 1975
Partner: UNT Libraries Government Documents Department

The effects of birth order and family size on children's locus of control

Description: The present study was concerned with investigating children's generalized locus of control of reinforcement and its possible relationship to the demographic variables of birth order and family size. The sample consisted of 93 school children in Grades 6, 7, and 8. The analysis of data was by a 2 x 3 factorial design.
Date: August 1975
Creator: Schniederjan, Patrick
Partner: UNT Libraries

Investigation of the parameters influencing the microstructure of hot-pressed boron carbide

Description: An investigation was conducted to determine the influence of various parameters on the microstructure of hot-pressed boron carbide compacts. It was determined that a critical temperature (approximately 2200/sup 0/C) was necessary to suppress exaggerated grain growth, and that exaggerated growth was also enhanced at higher pressures within the pressure range investigated. Microhardness examinations and twin density analyses were also performed, both of which demonstrated a primary dependence on grain size, with a secondary dependence occurring between microhardness and pressure and twin density and temperature. Fracture analysis indicated a mixed intergranular-transgranular fracture mode, with transgranular fracture predominating at smaller grain sizes. Also, observed bend strengths of fracture specimens are in resonable agreement with reported values. Electron microprobe scanning was performed on B/sub 4/C, B/sub 4/C + AlF/sub 3/, and B/sub 4/C + MgF/sub 2/. The results indicated a solubility of Al and Mg in the lattice. X-ray analysis was also conducted on B/sub 4/C + 10 percent AlF/sub 3/ specimens, and tended to confirm the formation of a B/sub 12/C/sub 2/Al compound, which apparently assumes an expanded B/sub 4/C unit cell configuration.
Date: November 1, 1975
Creator: Munir, Z. A. & Veerkamp, G. R.
Partner: UNT Libraries Government Documents Department

Impurity effects on the creep of polycrystalline magnesium and aluminum oxides at elevated temperatures. Technical progress report, December 19, 1974--December 18, 1975

Description: Work is reported on: 1. Viscous creep of fine-grained MgO doped with iron. 2. The effects of transition metal impurities and grain size on the creep of polycrystalline Al/sub 2/O/sub 3/. 3. The non-viscous creep of large grain size MgO and Al/sub 2/O/sub 3/, pure and doped with transition metal impurities. 4. Stress relaxation tests on polycrystalline MgO and Al/sub 2/O/sub 3/, pure and doped with transition metal impurities. 5. The construction of creep deformation maps for polycrystalline MgO and Al/sub 2/O/sub 3/, pure and doped with iron. 6. Preliminary studies on the effect of grain size on the creep of polycrystalline mullite. Some of the significant findings include: 1. Power law creep (N approx. 3) in polycrystalline MgO is independent of iron doping, grain size, and oxygen partial pressure. 2. Three well-defined regimes have been identified for the diffusional creep of polycrystalline MgO and Al/sub 2/O/sub 3/, pure and doped with transition metal impurities: (1) cation grain boundary diffusion (2) cation lattice diffusion, (3) anion grain boundary diffusion. 3. Coble diffusional creep, which is rate-limited by oxygen grain boundary diffusion, has been identified in reduced iron-doped (2 cation percent) and double doped (1/4 percent Mn and 1/4 percent Ti) polycrystalline Al/sub 2/O/sub 3/. Stress relaxation deformation tests can be used to (1) identify transitions between viscous and non-viscous deformation, and (2) achieve high stresses (approx. 10/sup 3/ kg/cm/sup 2/) and strain rates (1h/sup -1/) without fracture. Good agreement exists between dead-load creep and stress relaxation studies in four point bending. (auth)
Date: December 1, 1975
Creator: Gordon, R. S.
Partner: UNT Libraries Government Documents Department

Sample-size effects in fast-neutron gamma-ray production measurements: solid-cylinder samples

Description: The effects of geometry, absorption and multiple scattering in (n,X$gamma$) reaction measurements with solid-cylinder samples are investigated. Both analytical and Monte-Carlo methods are employed in the analysis. Geometric effects are shown to be relatively insignificant except in definition of the scattering angles. However, absorption and multiple-scattering effects are quite important; accurate microscopic differential cross sections can be extracted from experimental data only after a careful determination of corrections for these processes. The results of measurements performed using several natural iron samples (covering a wide range of sizes) confirm validity of the correction procedures described herein. It is concluded that these procedures are reliable whenever sufficiently accurate neutron and photon cross section and angular distribution information is available for the analysis. (13 figures, 5 tables) (auth)
Date: September 1, 1975
Creator: Smith, D.L.
Partner: UNT Libraries Government Documents Department

Effect of physico-chemical properties on metabolism of transuranium oxide aerosols inhaled by beagle dogs

Description: The oxides of four transuranium isotopes ($sup 238$Pu, $sup 239$Pu, $sup 241$Am, and $sup 244$Cm), prepared by identical methods of calcining the oxalate at 750$sup 0$C for two hours, had different physico-chemical properties. For all four oxides the density ranges from 9.8 to 11.4 g cm$sup -3$ and initial ultrafilterability (suspended fraction of activity less than 24 A) varied from 0.002 percent for $sup 239$PuO$sub 2$ to 2.24 percent for $sup 238$PuO$sub 2$. Dogs were exposed by nose-only techniques to aerosols generated by nebulizing water suspensions of the oxides. The dogs were sacrificed at intervals from one week to about a year postexposure. The rate of translocation of material from lung to other tissues increased from $sup 239$Pu to $sup 238$Pu to $sup 241$Am to $sup 244$Cm, possibly reflecting the decrease in mean particle size from an MMD of 0.7 $mu$m to $sup 239$PuO$sub 2$ to 0.6 $mu$m for $sup 238$PuO$sub 2$ to 0.4 $mu$m for $sup 241$AmO$sub 2$ to 0.1 $mu$m for $sup 244$CmO/sub x/. Accumulation of the isotopes in the liver and skeleton as a percentage of final body burden was 1 percent $sup 239$Pu and 7 to 23 percent for $sup 238$Pu at about a year postexposure, while at 270 days postexposure, values were 40 percent for $sup 241$Am and 40 to 30 percent for $sup 244$Cm. (auth)
Date: January 1, 1975
Creator: Craig, D.K.; Park, J.F. & Ryan, J.L.
Partner: UNT Libraries Government Documents Department

Fe--12Ni--4Co--2Mo--.05Ti alloy for use at 77$sup 0$K and below

Description: A variant of the maraging class of steels is proposed for application at 77$sup 0$K and below where a combination of very high strength and good toughness is required. The alloy has a composition of Fe-12Ni-4Co-2Mo-0.05Ti where low interstitial content. The as quenched and quenched and aged structures were completely martensitic with a prior austenitic grain size of 10 to 12 $mu$m. This structure had a Y.S. of 138.5 ksi and 154 ksi before and after aging respectively. All aging was done at 444$sup 0$C for 4 hours. The DBTT was shown to lie above 77$sup 0$K as measured by C/sub v/ testing. Based on dilatometric studies of the $alpha$ $Yields$ $gamma$ and $gamma$ $Yields$ $alpha$ transformation temperatures a cycling treatment consisting of reportedly heating to above the A/sub f/ temperature followed by a water quench was utilized to further reduce the prior $gamma$ grain size to approximately 4 to 6 $mu$m. The structure was completely martensitic and possessed a Y.S. of 151 ksi at 77$sup 0$K in the unaged condition with a Y.S./K/sub IC/ ratio of 1.9 while the aged structure showed a Y.S. of 162 ksi with a Y.S./K/sub IC/ ratio of 1.3. C/sub v/ testing showed the DBTT to lie between 77$sup 0$K and 4.2$sup 0$K. Further grain refinement was accomplished by a 2 phase decomposition procedure which resulted in a grain size of 1 to 2 $mu$m. The structure which contained decreasing amounts of austenite with temperature (3.0 percent at R.T. to 1.0 percent at 4.2$sup 0$K) showed the best combination of strength and ductility at 4.2$sup 0$K. A Y.S. of 205 ksi with a Y.S./K/sub IC/ ratio of 0.84 was achieved before aging. The aged structure was brittle at 4.2$sup 0$K with a Y.S. of 218 ksi and a Y.S./K/ sub IC/ ratio of 0.425. ...
Date: October 1, 1975
Creator: Whitaker, B.W.
Partner: UNT Libraries Government Documents Department

Helium bubbles at grain boundaries of high-density $sup 238$PuO$sub 2$ shards

Description: Hydroxide- and oxalate-base $sup 238$PuO$sub 2$ shards that were sintered to high density at 1200 or 1600$sup 0$C and then aged for 6 months or more exhibited grain-boundary gas bubbles due to agglomeration of alpha-decay helium when heated to 1200$sup 0$C and above. Conditions for bubble formation depended markedly on shard microstructure; large-grained shards with few large residual sintering pores formed gas bubbles at lower temperatures than small- grained shards with many pores. This behavior was especially apparent in oxalate- base $sup 238$PuO$sub 2$, in which small-grained shards resisted bubble formation to above 1500$sup 0$C; small-grained hydroxide-base shards with less internal porosity than oxalate-base shards formed bubbles at lower temperatures. Helium is apparently released from aged $sup 238$PuO$sub 2$ shards at high temperatures by bulk diffusion within grains to the grain boundaries, where bubbles are formed and interconnect into networks which permit helium escape. It is postulated that helium is released by grain boundary diffusion at temperatures below thresholds for grain boundary bubble formation. Small grain size and high residual porosity within grains inhibit the formation of the grain-boundary gas bubbles by reducing the concentration of helium gas at the grain boundaries. (10 fig) (auth)
Date: January 1, 1975
Creator: McDonell, W.R.; Sheenan, J.E. & Sisson, R.D.
Partner: UNT Libraries Government Documents Department

Physical and chemical characteristics of plutonium in existing contaminated soils and sediments

Description: Plutonium from three sites was studied to provide information necessary in understanding its behavior and fate under prevailing conditions. Plutonium in soils from the Nevada Test Site (NTS) was predominantly associated (50 to 75 percent) with the coarse silt (53 to 20 $mu$m) fraction. The plutonium in samples from Oak Ridge National Laboratory (ORNL) and Mound Laboratory (ML) was predominantly in the clay size (less than 2 $mu$m). The solubility in citric acid was about 20 to 25 percent in the ORNL sample and 40 to 50 percent in the ML sample. Density gradient segregation of the clay size fraction of the ML sample showed the activity distribution to be directly related to the weight of the recovered fraction with enhanced contribution by the very light organic fraction. Approximately 71 percent was found in the 2.3 to 2.4 g/cm$sup 3$ fraction which contained 65 weight percent of the clay and 16 percent in the less than 1.8 g/ cm$sup 3$ fraction (organic fraction) which contained 6 percent of the weight fraction. (auth)
Date: January 1, 1975
Creator: Tamura, T.
Partner: UNT Libraries Government Documents Department