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The 3 nu sub 3 absorption band of C-12H4 has been measured using a high-resolution vacuum infrared spectrometer. A technique is described which allows an extension of the use of the absorption standards available at 4.7 microns to the photomultiplier region of the spectrum. The new measurements indicate a shift of about 0.18 per cm from the most recently published measurements of this band.
Using parameters recently measured in the laboratory, the shapes of manifolds belonging to the R-branch of Saturn's 3 nu 3 CH4 band were analyzed in terms of a homogeneous scattering model of Saturn's atmosphere, and the results were compared with those of an earlier analysis in terms of a reflecting-layer model. The resulting effective pressure is an order of magnitude smaller than for the reflecting-layer analysis, and the C/H ratio is an order of magnitude higher than the solar value. The overall fit of the theoretical profiles to the observed manifold shapes is distinctly worse, especially for R(7). Scattering evidently plays only a minor role in the formation of this band along Saturn's south-central meridian.
The Mossbauer effect has proven to be effective in the study of nuclear hyperfine interactions. Ferrite systems having the formula (Zn(2+)0.3)(Mn(2+)0.7)(Mn(3+)y)(Fe(3+)2-y)(O4) were prepared and studied. These systems can be interpreted as mangacese-doped zinc and a part of iron ions. A systematic study of these systems is presented to promote an understanding of their microstructure for which various theories were proposed.
Band origins, secondary (or satellite) lines, and intensity anomalies are discussed for the infrared spectra of v sub 3 and 2v sub 3 of germane. Germane has been tentatively identified as spectroscopically active in the atmosphere of Jupiter. The molecule is also of interest for studies of isotope shifts in spherical-top spectra such as those measured in methane at 6000 kaysers.
An evaluation is presented which is defined as the adequacy of system design with known functional and performance requirements. The proposed Rockwell International AIDS 3 card, document and data flow are presented to summarize the concepts involved and the relationships between functions. The analysis and evaluation includes a study of system capability, processing rates, search requirements and response accuracy as well as a consideration of operational components and hardware integration. Results indicate that the AIDS 3 System concept is operationally feasible if production capacity is slightly enhanced but that operational complexity, hardware integration and a lack of conceptual data pertinent to some of the functions are areas of concern.
The six-volume report: describes the theory of a three dimensional (3-D) mathematical thermal discharge model and a related one dimensional (1-D) model, includes model verification at two sites, and provides a separate user's manual for each model. The 3-D model has two forms: free surface and rigid lid. The former, verified at Anclote Anchorage (FL), allows a free air/water interface and is suited for significant surface wave heights compared to mean water depth; e.g., estuaries and coastal regions. The latter, verified at Lake Keowee (SC), is suited for small surface wave heights compared to depth (e.g., natural or man-made inland lakes) because surface elevation has been removed as a parameter. These models allow computation of time-dependent velocity and temperature fields for given initial conditions and time-varying boundary conditions. The free-surface model also provides surface height variations with time.
Thermoluminescence (TL) sensitivity values for sixteen type 3 ordinary chondrites, fourteen of them from Antarctica, have been measured. The values obtained (normalized to the TL sensitivity of the Dhajala meteorite) range from 1.6 (Allan Hills A77216) to 0.010 (Allan Hills A77176), and include two (Reckling Peak A80207 and Allan Hills A77176) that are particularly low. They fill a hiatus in the TL distribution that previously existed between St. Mary's County and Bishunpur, the latter being a meteorite with one of the lowest TL sensitivities known. The histogram of TL sensitivity values now shows a single distribution with higher values preferred; it resembles the histogram for L chondrites occupying the petrologic types 3, 4, 5, and 6. There is a tendency for the TL sensitivity of meteorites to decrease as delta O-18 increases. Theoretically, it is possible that the range of delta O-18 values observed may reflect progressive loss of O in the form of CO at very low temperatures, but very restrictive physical conditions and a complex history seem to be required.
An estimation technique was developed to extrapolate tidal amplitudes and phases over entire ocean basins using existing gauge data and the altimetric measurements provided by satellite oceanography. The technique was previously tested. Some results obtained by using a 3 deg by 3 deg grid are presented. The functions used in the interpolation are the eigenfunctions of the velocity (Proudman functions) which are computed numerically from a knowledge of the basin's bottom topography, the horizontal plan form and the necessary boundary conditions. These functions are characteristic of the particular basin. The gravitational normal modes of the basin are computed as part of the investigation; they are used to obtain the theoretical forced solutions for the tidal constituents. The latter can provide the simulated data for the testing of the method and serve as a guide in choosing the most energetic functions for the interpolation.
Numerical experiments have been conducted which indicate that the orbital eccentricity of Miranda may have reached a value sufficiently large to have affected its thermal evolution. There is a large chaotic zone associated with the Miranda-Ariel 5:3 mean-motion commensurability, even in the planar approximation; the orbital eccentricities of both satellites may vary chaotically for a considerable period. Since the anomalously high orbital inclination of Miranda is a consequence of passage through the 3:1 commensurability with Umbriel, the requirement that the satellites encountered this resonance places a lower limit on the Uranian specific dissipation function of 39,000.
In Volume 3 of Phase 3 of the Space Shuttle Probabilistic Risk Assessment, the basic events database and minimal cutsets are presented, along with their predicted probability in tabular form.
Experimental and theoretical excitation cross sections are reported for the first forbidden transition 4S(O) -- 2S(2)2p(3) 2D(O) (lambda-lambda 3726, 3729) and the first allowed (resonance) transition 4S(O) -- 2s2p(4) 4P(lambda-833) in O II. Use is made of electron energy loss and merged-beams methods. The electron energy range covered is 3.33 (threshold) to 15 eV for the S -- D transition, and 14.9 (threshold) to 40 eV for the S -- P transition. Care was taken to assess and minimize the metastable fraction of the O II beam. An electron mirror was designed and tested to reflect inelastically backscattered electrons into the forward direction to account for the full range of polar scattering angles. Comparisons are made between present experiments and 11-state R-matrix calculations. Calculations are also presented for the 4S(O) -- 2s(2)2p(3)2P(O) (lambda-2470) transition.
It is demonstrated that a longitudinal magnetic field applied to a low-pressure, low-voltage, hot cathode glow discharge will substantially increase the intensity of metastable atoms effusing from a central anode slit. For an argon discharge there is a fourfold increase in the effusing Ar((sup 3)P(sub 2, 0)) atom intensity and for neon there is a 14-fold increase in Ne((sup 3)P(sub 2, 0)) intensity.
The optical spectra of rare earth ions in solids arise primarily from electric and magnetic dipole transitions between stark split multiplets of the 4f(sup N) electronic configuration. Electric dipole transitions are parity forbidden between levels of the 4f(sup N) configuration, while those of magnetic dipole origin are allowed. It is known from experiment, however, that the significant contributions to the intensities of most transitions are electric dipole in nature. Judd and Ofelt developed the theory of forced electric dipole transitions of rare-earth ions. This study is devoted to determining electric dipole transition probabilities and branching ratios for Tm(3+) and Ho(3+) ions in Yttrium Aluminum Garnet (YAG) and Yttrium Lithium Fluoride (YLF) using the theory of Judd and Ofelt. The radiative rates determined from the Judd-Ofelt analysis are used with measured lifetimes to find nonradiative rates of relaxation.
Experimental and theoretical collisional excitation cross sections are reported for the transitions 3s(exp 2)3p(exp 3)4S(exp o) approaches 3s(exp 2)3p(exp 3) 2D(exp o), 2P(exp o), and 3s3P(exp 4) 4P in S II. The transition wavelengths (energies) are 6716 A (1.85 eV), 4069 A (3.05 eV), and 1256 A (9.87 eV), respectively. In the experiments, use is made of the energy-loss merged-beams method. The metastable fraction of the S II beam was assessed and minimized. The contribution of elastically scattered electrons was reduced by the use of a lowered solenoidal magnetic field and a modulated radio-frequency voltage on the analyzing plates and by retarding grids to reject the elastically scattered electrons with larger Larmor radii. For each transition, comparisons are made among experiments, the new 19 state R-matrix calculation, and three other close-coupling calculations.
2,5-Bis(perfluoro-n-heptyl)-, 2-perfluoroalkylether-5-perfluoro-n- heptyl- , and 2 , 5-bisperfluoroalkylether-1,3,4-oxadiazoles were synthesized and characterized. 2,5-Bis(perfluoro-n-heptyl)-1,3,4-oxadiazole was thermally and hydrolytically stable at 325 C; however, in the presence of air, degradation took place at 235 C. The perfluoroalkylether analogue exhibited thermal and hydrolytic stability at 325 C; it was found to be unaffected by jet-A fuel and air at 235 C. At 325 C in air some degradation occurred as evidenced by volatiles production, oxygen consumption, and 96% starting material recovery.
Live footage shows some beautiful panoramic views of STS-37 on the pad. Scenes include the narration of simulated auto sequence start, engine start, engine firing and cut-off. Also shown is the crew emergency egress procedure. This is tape 3 of 3. Tape 1 has a report # of NONP-NASA-VT-2000013416, and tape 2 has a report # of NONP-NASA-VT-2000013417.
Polyimide copolymers were obtained containing 1,3-bis(3-aminophenoxy)benzene (APB) and other diamines and dianhydrides and terminating with the appropriate amount of a non-reactive endcapper, such as phthalic anhydride. Homopolymers containing only other diamines and dianhydrides which are not processable under conditions described previously can be made processable by incorporating various amounts of APB, depending on the chemical structures of the diamines and dianhydrides used. Polyimides that are more rigid in nature require more APB to impart processability than polyimides that are less rigid in nature. The copolymers that result from using APB to enhance processability have a unique combination of properties including excellent thin film properties, low pressure processing (200 psi and below), improved toughness, improved solvent resistance, improved adhesive properties, improved composite mechanical properties, long term melt stability (several hours at 390 C), and lower melt viscosities.
Tests of two-blade propellers having the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 blade designs (blade activity factors of 179 and 263, respectively) have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 70 degrees for free-stream Mach numbers from 0.165 to 0.725 to determine the effects of high solidity and compressibility on propeller characteristics. The tests are part of a general investigation of propellers at high forward speeds. Results previously reported for similar tests of two-blade propellers having the NACA 4-308-03 and NACA 4-308-045 blade designs (blade activity factors of 87 and 133, respectively) are included for comparison. The results showed that the 0.06- and 0.09-solidity blades, although producing efficiencies of the order of 90 percent, were less efficient than blades of conventional solidity. The variation in average blade lift coefficient with solidity at a constant blade angle and advance-diameter ratio through the speed range of these tests was found to be analogous to the variation of wing lift coefficient with aspect ratio, indicating that high-solidity blades may be desirable at very high speeds. Because of power limitations of the test equipment, conclusive evidence of the possible favorable effects of increased blade solidity at high speeds was not obtained. Further tests are desirable.