calculated values. There is essentially no difference between the surface and the bulk layers of CdS crystals, insofar as the optical properties are concerned. The use of thin single-crystal films makes it possible to measure the spectral distribution of absorption and dispersion in a polarized light in a wide region beyond the absorption limit, corresponding to the excitation of the depth of the conduction band. Based on these data, certain conclusions can be made relative to the intensity and the polarization of structural absorption, which then makes this convenient and useful method for the study of band structure of crystals. Author (GRA) N72-10797# Air Force Systems Command, Wright-Patterson AFB, Ohio. Foreign Technology Div. THE QUESTION OF CURRENT DISTRIBUTION IN COMBINED SUPERCONDUCTORS V. V. Sychev and V. A. Alton 12 May 1971 20 prefs Transl. into ENGLISH from Izv. Akad. Nauk SSSR, Energ. i Transp. (Moscow), no 5, 1970 p 84-91 (Project 6040102) (AD-727551; FTD-MT-24-92-71; UR/0281-70-000-005) Avail: NTIS CSCL 20/3 A complete and consistent picture of the current distribution in combined superconductors has been obtained. It is shown that the resistance of the superconductor itself can be directly commensurable with the resistance of the base layer material. Author (GRA) N72-10798# Wisconsin Univ., Madison. Dept. of Statistics. THE ATOM PROBE AND MARKOV CHAIN STATISTICS OF CLUSTERING Jerome H. Klotz and Charles A. Johnson (Argonne Natl. Lab.) Apr. 1971 36 p refs Sponsored in part by AEC (Grant NSF-GP-12093) (PB-200569; UWIS-DS-71-267) Avail: NTIS CSCL 07D The field ion microscope atom probe, used in the exploration of crystal structure, is discussed. Data is generated from a probe of an alloy of two types of metalic elements. A statistical model is formulated to investigate clustering of like atoms within the alloy. Physical considerations motivate a Markov chain generalization of the binomial model. A parameter in the model which measures the degree of clustering estimated by maximum likelihood and large sample distribution theory is given using results from Billingsly. A combinatorial analysis is developed which provides the exact distribution of the sufficient statistics and permits small sample comparisons of expectations and mean square errors of estimates with their large sample approximations. Author (GRA) N72-10799# Case Western Reserve Univ., Cleveland, Ohio. A technical summary of the research performed under AF-AFOSR-68-1484 is presented. Basic information on the material parameters important in determining dynamic magnetization processes in ferromagnetic films are given, and the relationship between energy bands and the spin wave dispersion in the 3d ferromagnetic elements is summarized. Author (GRA) N72-10800# Technische Hochschule Stuttgart (West Germany). Inst. fuer Anorganische Chemie. ELECTRICAL CONDUCTIVITES UP TO 1000 C IN THE Ge-As-Te SYSTEM Ph.D. Thesis [ELEKTRISCHE LEITFAE HIGKEITEN BIS 1000 C IM SYSTEM GE-AS-TE] Peter Fischer 1970 136 p refs In GERMAN Sponsored jointly by Deut. Forsch. Gemeinschaft and Fonds der Chemie GROWTH AND CHARACTERIZATION OF TETRAGONAL (RUTILE) Ge02 CRYSTALS John W. Goodrum 12 Mar. 1971 31 p refs The use of germanium in semiconductor devices continues in importance but adequate substrate materials and/or passivating (insulating) films for Ge are still lacking. Although such properties of the tetragonal oxide of germanium as chemical inertness and low electrical conductivity indicate it would be an excellent substrate/passivating material for Ge semiconductor devices. various attempts to prepare this oxide have met with only limited success (Albers, Valyocsik, and Mohan, 1966; Carasso and Faktor, 1965; Wilkes, 1964). This report describes a preparation method for this oxide as well as some previously unreported characteristics of the material. Author (GRA) In support of research being conducted by the Properties and Phenomena Branch, Solid State Science Laboratory, Air Force Cambridge Research Laboratory. ManLabs, Inc. is conducting a service effort that is directed toward the characterization of specified physical, chemical and structural properties of various materials. Experimental methods include chemical analysis, reflection electron microscopy and diffraction, X-ray diffraction and fluorescence analysis, light microscopy and electron microprobe analysis, in addition to the determination of specific properties, such as density, hardness and thermal conductivity. Special services, such as crystal orientation, cutting, grinding and polishing are also being performed. Specific materials submitted for characterization include spinel, lithium germanate, silicon, silicon carbide, quartz, ruby, magnesium oxide, copper chloride, gallium arsenide, boron, potassium tantalum niobate, yttrium-iron garnet, yttrium-aluminum garnet and lithium niobate. In addition, a variety of specimens have been submitted for specific studies such as phase identification, crystallinity and chemical analysis. Author (GRA) N72-10803# lowa Univ., Iowa City. A THEORY OF VISCOPLASTICITY WITHOUT A YIELD SURFACE. PART 2: APPLICATION TO MECHANICAL BEHAVIOR OF METALS K. C. Valanis Jan. 1971 32 p refs (Grant AF-AFOSR-1916-70) (AD-725026; AFOSR-71-1766TR-PT-2) Avail: NTIS CSCL 20/ 12 The endochronic theory of viscoplasticity developed previously by the author is used to give quantitative analytical predictions on the mechanical response of aluminum and copper under conditions of complex strain histories. One single constitutive equation describes with remarkable accuracy and ease of calculation diverse phenomena, such as cross-hardening, loading and unloading loops, and cyclic hardening as well as behavior in tension in the presence of a shearing stress, which have been observed experimentally by four different authors. Author (GRA) N72-10804# Massachusetts Inst. of Tech., Cambridge. Solid State Research Group. HIGH ELECTRIC FIELD TRANSPORT IN THE LEAD CHALCOGENIDES Hugues St.Onge Apr. 1971 162 prefs (Contract NO0014-67-A-0204-0010; MIT Proj. DSR-70421) (AD-725165; TR-8) Avail: NTIS CSCL 20/12 Nanosecond pulse techniques were used to measure the velocity-field characteristics of bulk samples of n-type PbSe, PbTe and Pb(.83)Sn(.17)Te at 77K and 4.2K for carrier concentrations ranging from 1 x 10 to the 17th power/cc to 5 x 10 to the 17th power/cc. At fields of a few hundred volts/cm, strong deviations from ohmic conduction are observed, the velocity showing a clear tendency towards saturation. The theoretical analysis of the results shows that at high electric fields polar optical scattering is dominant in the Pb salts. The results obtained for electric fields above the threshold for impact ionization are consistent with carrier generation if the Pinch effect is taken into account. Author (GRA) N72-10805# GTE Labs., Inc., Bayside, N.Y. JUNCTION GROWTH TECHNIQUES FOR GaAs AVALANCHE TRANSIT TIME DEVICES Semiannual Report, 1 Jul. 31 Dec. 1970 James F. Black and Richard H. Deitch Apr. 1970 38 p refs (Contract DAAB07-70-C-0320: DA Proj. 1H6-62705-A-056) (AD-724705; TR-71-837.1: ECOM-0320-1) Avail: NTIS CSCL 20/2 New techniques of liquid phase epitaxial growth have been employed to prepare GaAs wafers with thin high quality n layers and p(-) layers. Wafers have been produced in p(-)-n-n(-) configurations; with abrupt p(-)-n and abrupt n-n(-) junctions; with p(-) layers 1 to 3 micrometers thick and doping levels as high as 2 x 10 to the 19th power/cc; with n layers of average thickness 3 micrometers, electron concentration in the range 1 to 4 x 10 to the 16th power/cc and mobility greater than 5000 sq cm/V.sec at room temperature. These epitaxial layers have been grown on n(-) substrate wafers with dislocation densities ranging from 500/sq cm to about 100/sq cm, electron concentrations in the range of 1 to 4 x 10 to the 18th power and electron mobilities ranging from 2500 sq cm/V.sec to 2000 sq cm/V.sec. The procedures and apparatus used for preparation of these epitaxial wafers are described in detail. In addition, the evaluation of these epitaxial wafers by techniques of capacitance-voltage profiling, infrared interference fringe measurement and X-ray anomalous diffraction contrast topography is described. Author (GRA) (NLL-PORS-Trans-2782-(9022.81)) Avail: Natl. Lending Library. Boston Spa, Engl.: 1 NLL photocopy coupon The eddy current method for measuring film thickness of metallic vapor deposited films is examined. The measuring apparatus contains an electrically and geometrically formed search coil, which is set up in the receiver on the reverse side of the substrate which is to be layered. The measured results were observed directly at the substrate during the formation of the film by condensation. When the deposition parameters are stabilized, the reproducibility of definite thicknesses is better than 90%. E.M.C. N72-10808 National Lending Library for Science and Technology. Boston Spa (England). ELECTROPHYSICAL PROPERTIES OF Mo-Si SCHOTTKY BARRIERS P. Schley and R. Sperling 19 Aug. 1971 3 p Transl. into ENGLISH from Nachrichtentech. Elektron. (Berlin), v. 20, no. 12. 1970 p 452-453 (NLL-PORS-Trans-2779-(9022.81)) Avail: Natl. Lending Library. Boston Spa, Engl.: 1 NLL photocopy coupon The practical production of components with a blocking metal semiconductor junction is discussed. Special technological precautions to avoid the occurrence of contaminant layers between metal and semiconductor, which might affect the function of such components are presented. The effect of contaminant layers on carrier transport in the metal semiconductor junction can be ascertained by measuring the electrical properties of the junction. An installation with suitable measuring equipment was set up for the production of metal semiconductor junctions. The chemical deposition of molybdenum films on n-conducting epitaxial silicon in a pyrolysis process was chosen from the possible methods of producing metal semiconductor structures. The reasons for this choice were that interaction in the Mo-Si system only occurs at relatively high temperatures (700 C), that the use of vacuum equipment was to be avoided, and that this method seems suitable in principle for industrial production. Author N72-10809 National Lending Library for Science and Technology. Boston Spa (England). TEMPERATURE AND ORIENTATION DEPENDENCE OF DEFORMATION CHARACTERISTICS OF SINGLE CRYTALS N. T. Travina and A. A. Nikitin 2 Sep. 1971 4 p refs Trans!. into ENGLISH from Fiz. Metal. Metalloved. (Sverdlorsk), v. 30. no. 6, Dec. 1970 p 1291-1296 In RUSSIAN and ENGLISH (NLL-TRANS-746-886-(9022.401)) Avail: Natl. Lending Library, Boston Spa, Engl.: 1 NLL photocopy coupon The results of elongation tests of single Ni3Al crystals at different orientation, deformed within the temperature range of -196 to 600 C are given. A clearly expressed orientation dependence of the critical shear stress and coefficient of deformation hardening was observed. A considerable increase in these characteristics is observed for crystals with an orientation close to (100). The temperature dependence of critical shear stress and deformation hardening their increase with an increase in temperature is analogous to that observed earlier on polycrystalline and single Ni3Al crystals. The results obtained were investigated from the point of view of existing dislocation models of hardening of ordered alloys with a LI2 structure. Author N72-10810 Louisiana State Univ., Baton Rouge. Oscar Lucien Steenhaut 1970 100 p The Fermi surface of zinc is determined from calipers obtained through RF size effect measurements. The 6- to 8-MHz RF measurements were performed at 1.2 K on high purity monocrystals of zinc approximately 0.5 mm in thickness. The Fermi surface was calipered using samples whose normals to the surfaces were parallel to one of the three principal symmetry direction /0001/, /10(-1)0/, and /11(-2)0/, with magnetic field rotations in the plane of the sample. Calipers are assigned to definite orbits on the first- and second-band hole surfaces and the third-band electron surface. Calipers are given for the first-band hole surface and the spin orbit induced gaps between the first and second bands are discussed. The second-band hole surface is discussed in detail with the assignment of 30 series of calipers to definite orbits on this sheet of the Fermi surface. Dissert. Abstr. N72-10811 Stanford Univ., Calif. NOISE EMISSION FROM INDIUM ANTIMONIDE Ph.D. Thesis Arthur Howard Thompson 1970 78 p Avail: Univ. Microfilms Order No. 70-18488 An explanation is presented for broadband, high frequency noise emission which is consistent with the experimental data previously reported. The explanation is based on the existence of localized high electric field regions that occur near discontinuities in the sample geometry or in the electrical properties. These high field regions cause local electron avalanche and the resulting electron hole plasma is the source of the noise emission. Dissert. Abstr. ORDERED N72-10812 California Univ., Berkeley. The deformation behavior of single crystals of AgMg intermetallic compound (CsCl type structure) of various orientations in the standard stereographic triangle was investigated in tension over the range from 20 to 300 K and in compression at 237.5 K. The plastic behavior shows asymmetry in both the critical resolved shear stress for slip on the /112/ planes and in the strain hardening. Dissert. Abstr. N72-10813 Louisiana State Univ., Baton Rouge. CALCULATION OF ENERGY BANDS FOR NICKEL SULFIDE Ph.D. Thesis John Miller Tyler 1970 87 p Avail: Univ. Microfilms Order No. 70-18568 Energy bands are calculated for hexagonal NiS using lattice constants and crystal potential appropriate to the paramagnetic metallic phase. Group theoretic results for s, p and d bands in NiAs structure are obtained and the calculation is performed using a first principles, tight-binding method. The energy band structure is characterized by a 3d band about 3 volts wide hybridized with a broad s-p band, indicating s-d type conductivity. The Fermi energy lies just below the top of the d bands and the density of states exhibits a strong, sharp peak about one volt below the Fermi energy. Since the energy bands suggest that there will be considerable structure in the low energy region of the reflectivity, selection rules, polarizations, and energies for some of the spectra are presented. The band structure is discussed in terms of the metal-to-semiconductor transition which has been observed for hexagonal NiS. Dissert. Abstr. N72-10814 Stanford Univ., Calif. ENERGY-LOSS MECHANISMS IN SEMICONDUCTOR Avail: Univ. Microfilms Order No. 70-18513 The energy-loss mechanism due to ionization is investigated in lithium-drifted silicon and germanium semiconductor radiation detectors. A simple phenomenological model is presented which accounts for the energy losses in the formation of an electron-hole pair. Experiments were performed to measure the energy expended to produce a pair in silicon. Good agreement between theory and experiment was obtained for the absolute value of electron hole pair at room temperature and at 77 K in silicon. In germanium, the theoretical values were compared to the experimental results. After weighting the conduction band energies of the valleys in the <111> and <100> directions according to their respective density of states to obtain an effective ionization band-gap energy, good agreement between theory and experiment was also obtained in germanium. Dissert. Abstr. N72-10815 Louisiana State Univ., Baton Rouge. Energy bands of vanadium oxide were calculated by the tight-binding method. The method of Lafon and Lin was extended to include 3p, 3d, and 4s functions, so that three-center integrals could be included in the calculations. All matrix elements were summed to convergence, and the core functions of both vanadium and oxygen were included explicitly. The crystal potential was constructed from a superposition of spherically-averaged atomic potentials. Band structures were calculated using three different crystal potentials. The density of states was computed from a sample of 505 points in 1/48 of the Brillouin zone. The effect of including core states was examined in detail, as were the effects of varying the factor lambda in the exchange potential. Using the three different band structures which were computed, an estimate of the self-consistent potential was made. Dissert. Abstr. N72-10816 Stanford Univ., Calif. LUMINESCENCE, TRAPPING AND F CENTER IN LITHIUM Avail: Univ. Microfilms Order No. 70-18449 The validity of previously proposed models was checked. The basic data needed for the formulation of a more comprehensive model are provided. The following experimental techniques were used: optical absorption in the visible and vacuum ultraviolet regions, irradiation with X-rays and ultraviolet light from a microwave discharge source, measurement of total luminescence output and luminescence emission spectra as a function of temperature, optical and thermal bleaching of absorption centers, and thermally stimulated luminescence. In addition to obtaining specific quantitative data on the parameters of the F center, hole traps, and luminescence centers in lithium fluoride crystals. information is also provided on the interactions between these imperfections. A model is proposed that is consistent with the results obtained. Alpha and beta absorption bands of lithium fluoride were tentatively identified. Dissert. Abstr. N72-10817 Rensselaer Polytechnic Inst., Troy, N.Y. IMPURITY EFFECTS ON THE STRUCTURE AND PROPERTIES OF NON-CRYSTALLINE SELENIUM Ph.D. Thesis William Carl La Course 1970 391 p Avail: Univ. Microfilms Order No. 70-19941 The structure of glassy selenium was investigated using infrared spectroscopy. Other methods, including absorption edge measurements, electron spin resonance, and DTA were employed to a lesser degree. Effects of various impurities on the structure were also investigated, and an attempt was made to determine how impurities bond in selenium. The electrical conductivity was measured using impurity contents as the major variable. From results of this work, a mechanism for the conductivity of pure selenium can be postulated, and is based on the assumption of intermolecular barriers to hole motion. Using the results on oxygen impurities the intermolecular barrier is estimated to be .4 eV. The carrier concentration in pure selenium is postulated to be governed by acceptor levels with an ionization potential of .75 -85 eV. Dissert. Abstr. N72-10818 Princeton Univ., N.J. Richard William Nosker 1970 308 p The importance of the long range electrostatic force in determining surface characteristics was assessed. Electrostatic potentials were calculated both in the bulk and at the principal surfaces of both wurtzite and zincblende. The nonpolar surfaces were assumed to be ideally terminated; for this case, it was found that the electrostatic potential reached the bulk value within three or four layers of the surface. The polar surfaces must be terminated in such a way that each surface has a monopole moment which cancels a bulk monopole moment built up from the contributions of many dipole moments due to double layers of charge throughout the crystal. The calculated electrostatic potentials were used to determine electrostatic surface energies for each of the arrangements considered on the low-index surfaces. It was found that the inherent simplicity of the electrostatic field in the point-ion approximation allows a fairly extensive determination of three dimensional lattice properties in cases where the crystal has a reasonable degree of ionicity. Dissert. Abstr. N72-10819 Pennsylvania State Univ., University Park. PRECISION MEASUREMENT OF THE ELASTIC CONSTANTS OF SOLIDS AND THEIR TEMPERATURE AND PRESSURE VARIATIONS Ph.D. Thesis David L. Miller 1969 88 p Avail: Univ. Microfilms Order No. 70-19439 Two methods of measuring elastic constants have been investigated. The phase comparison method was used to measure single crystal selenium at 25 C. The values obtained are given along with measurements of the slopes in the temperature range of 15 C to 35 C. The pulse superposition method was used for obtaining the elastic constants for selenium glass at 25 C, and the elastic constants for tellurium single crystal at room temperature. The pulse superposition method was modified by the addition of an automatic frequency control feature. This allowed high precision measurement of changes in acoustic wave delay time. A stability of or 2 parts in 10 to the 7th power during a 15 minute interval was obtained. Using a lithium fluoride sample, 12 temperature intervals of approximately 0.50 C were measured from 19.00 C to 25.01 C. N72-10820 Utah Univ., Salt Lake City. Dissert. Abstr. ELECTRO OPTICAL EFFECTS OF F SUB A CENTERS IN Avail: Univ. Microfilms Order No. 70-19080 The effects of high electric fields on the optical absorption of F sub A centers in KCI Li were measured for various geometrical configurations. The intrinsic lack of inversion symmetry of the center resulted in a displacement of the wavefunctions for ground and excited states. The corresponding dipole moment differences, causing a shift of the optical transition energy under applied field, were determined in size and sign. Further reduction of the center symmetry by the Li(+) occupying off-axis states, lead to low temperature effects from a redistribution of the Li(+) among the states by the applied field. The size and <110> orientation of the corresponding Li displacement dipole moment were obtained from an analysis of the data. The strong internal field from the Li(+) displacement dipole caused a mixing of the close lying 2s and 2p states. This resulted in an internal Stark effect of the optical transitions. 27 PROPELLANTS Dissert. Abstr. Includes fuels; igniters; and oxidizers. For basic research see: 06 Chemistry; and 33 Thermodynamics and Combustion. For related information see also: 28 Propulsion Systems. Elwin C. Dickson Apr. 1971 82 prefs (Contract F04611-70-C-0068) (AD-725045; TRW-4557; AFRPL-TR-71-52) Avail: NTIS CSCL 19/1 The report describes a stress analysis computer program for non-homogeneous elastic solids in a three dimensional state of stress. The continuum can be enclosed in a membrane case. The displacement equations of equilibrium can be based on the usual potential energy variational principle, or they can be based on Herrmann's variational theorem for solids with high Poisson's ratio such as propellant grain. The HVT formulation assumes constant hydrostatic pressure over each double-dodecahedral element, and both formulations assume linear displacements over each of the 10 tetrahedral subelements. Problems involving a Poisson's ratio of 0.499 and having 10,560 displacement components have been run successfully on the CDC 6600 computer. Plane stress membrane is assumed for the case. The system of equations is solved by a direct elimination technique and the solution substituted back into the system to check the validity of the solution. Author (GRA) N72-10823# Instituto Nacional de Tecnica Aeroespacial, Madrid (Spain). SUPERCRITICAL COMBUSTION OF FUELS AND PROPELLANTS IN DROPLETS Final Report, 1 Apr. 1968 31 May 1969 Carlos Sanchez Tarifa, Antonio Crespo, Enrique Fraga, and Antonio Munoz 1 Apr. 1971 47 p refs (Grant EOOAR-0027-68; AF Proj. 9711-01) (AD-725749; AFOSR-71-1848TR) Avail: NTIS CSCL 21/2 The actual importance of the problem is discussed, and the theoretical and experimental evidence existing on the problem are briefly reviewed. A model for the theoretical study of the process is established assuming spherical symmetry, laminar conditions, and a zero thickness flame. Boundary conditions are thoroughly analyzed, showing that complete stationary theories cannot be applied. Further assumptions are introduced in order to solve the problem which leads to the study of two different models of the process, which differ, on the physical conditions assumed at the droplet surface. Author (GRA) 28 PROPULSION SYSTEMS Includes air breathing, electric, liquid, solid, and magnetohydrodynamic propulsion. For nuclear propulsion see: 22 Nuclear Engineering. For basic research see: 23 Physics, General; and 33 Thermodynamics and Combustion. For applications see: 31 Space Vehicles. For related information see also: 27 Propellants. N72-10824*# National Aeronautics and Space Administration. GAS TURBINE ENGINE FUEL CONTROL Patent Application A variable-orifice system that is responsive to compressor inlet pressure and temperature, compressor discharge pressure, and rotational speed of a gas turbine engine is incorporated into a hydraulic circuit. The circuit includes a zero gradient pump driven at a speed proportional to the speed of the engine. The resulting system provides control of fuel rate for starting, steady running, acceleration, and deceleration under varying altitudes and flight speeds. NASA N72-10825# Deutsche Forschungsanstalt fur Luft- und Raumfahrt. Brunswick (West Germany). Inst. fuer Elektrische Antriebe und Energieversorgung THE ELECTROSTATIC ION THRUSTER ESKA-18-P OF THE DFVLR BRUNSWICK [DAS ELEKTROSTATICHE IONENTRIEBWERK ESKA-18-P DER DFVLR BRAUNSCH WEIG] Hans-Juergen Arlt. Siegried Baumgarth, Harro Bessling, Werner Kleinkauf, and Uwe Sprengel Bad Godesberg. West Ger. Bundesmin. fuer Bildung und Wiss. Jun. 1971 53 p refs In GERMAN: ENGLISH summary Sponsored by Bundesmin. fuer Bildung und Wiss. (BMBW-FB-W-71-26) Avail: NTIS; ZLDI Munich: 11.20 DM Results of investigations carried out on the electrostatic ion thruster ESKA-18-p are presented. The thruster discharge characteristics as well as power conditioning and control are discussed. Separate measurements on a hollow cathode and a vaporizer are given, and beam diagnostics using Faraday probes are provided. The dependence of power input on the mass utilization factor is demonstrated and application of the thruster as a solar electric propulsion module of 2.5 kW is shown. ESRO N72-10826# Southampton Univ. (England). Dept. of Aeronautics and Astronautics. A PRELIMINARY INVESTIGATION OF AN AIRAUGMENTED ROCKET USING A ONE-DIMENSIONAL FLOW MODEL D. J. Rickeard Jun. 1971 57 prefs (AASU-306) Avail: NTIS Performance estimates have been made for an air-augmented rocket system based on a small rocket of 2500 N thrust, using a one-dimensional inviscid flow analysis. Thrust augmentation of up to 47% of the rocket thrust is predicted for quite modest fuel/oxidizer ratios subject to complete mixing and burning of the fuel stream with the entrained air. Augmentation leads to a greater thrust enhancement at a freestream Mach number of 1.5 and 0.9. It has been found that there is an optimum value for the rocket exhaust Mach number, and that the secondary stream Mach number should be less than about 0.7 at entry to the secondary combustion chamber for optimum thrust. Thrust enhancement has been found to be conditional on careful design of the secondary duct, and the most successful configurations to involve increasing pressure along the walls of the secondary combustion chamber. Author (ESRO) N72-10827# Institut fuer Chemie der Treibstoffe, Berghausen (West Germany). THERMODYNAMIC CONSIDERATIONS OF LIQUID RAMJET ROCKET PROPULSION SYSTEMS [THERMODYNAMISCHE UEBERLEGUNGEN AN FLUESSIGS TAUSTRAHL-RAKETENANTRIEBEN] F. Volk 15 Aug. 1971 29 p refs in GERMAN (ICT-2/71) Avail: NTIS The chemical and technical possibilities of producing a high calorific cracking gas for energy supply to a ramjet engine in a combined propulsion system are discussed. The problems involved in partial combustion, and thermal and catalytic cracking of hydrocarbons are treated. It is shown that the method of partial combustion, as well as the pyrolytic cracking of hydrocarbons using hot rocket exhaust gases, is promising. ESRO N72-10828# Messerschmitt-Boelkow-Blohm G.m.b.H., Munich (West Germany). Unternehmungsbereich Flugzeuge. BASIC INVESTIGATIONS OF RECIRCULATION WITH CONFIGURATIONS CONSISTING OF 1 TO 6 JETS [GRUNDSATZUNTERSUCHUNGEN ZUR REZIRKULATION AN 1 BIS 6-STRAHLANORDNUNGEN] F. Aulehla, W. Eder, and V. Zeidler Bonn Bundeswehramt 1971 60 p In GERMAN; ENGLISH summary Sponsored by Bundesmin. fuer Verteidigung (BMVG-FBWT-71-12) Avail: NTIS; Bundeswehramt, Bonn: 25 DM Analyses of the fundamental factors were performed and model tests were carried out to determine the mechanism of recirculation in jet powered V/STOL aircraft and to devise methods for preventing or reducing the occurrence of thrust loss, engine surge and flame-out for differing engine configurations. Preliminary studies of the correlation between model measurements and full-size operation, and flow effects from forward, aft and the sides on a lift thrust configuration, are separated. ESRO N72-10829# Northern Research and Engineering Corp., Cambridge, Mass. Willem Jansen, Michael C. Swarden, and Albert W. Carlson Jan. 1971 184 p refs 2 Vol. (Contract NO0019-69-C-0602) (AD-728024; NREC-1149-2-Vol-2) Avail: NTIS CSCL 21/5 The report is the second volume of a report describing the results of an analytical investigation of compressor sensitivity, conducted under Contract No. NO0019-69-C-0602 for the Department of the Navy, Naval Air Systems Command. The objectives of the investigation were to develop an analytical model which simulates compressor response to spatial and temporal flow disturbances; to establish by application of the model the importance of various flow mechanisms, and their relationship to design variables, in determining compressor response; and to establish some design trends by means of a limited parametric study. This volume contains the detailed mathematical development of the models and the theoretical background of the equations that were utilized; the results of the studies are described in general terms in Volume 1. N72-10830# Mitre Corp., McLean, Va. Author (GRA) A SURVEY OF PROPULSION SYSTEMS FOR LOW EMISSION URBAN VEHICLES W. E. Fraize and R. K. Lay Sep. 1970 116 p refs Sponsored by DOT (Contract F19628-68-C-0365) (PB-200144; UMTA-TRD-52-70-2; M70-45) Avail: NTIS CSCL 13F An overview is presented of low and negligible emission urban vehicle technology. Propulsion systems suitable for low emission urban vehicles are described. The state-of-the-art of low |