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The composition of the time-resolved surface pressure field around a high-pressure rotor blade caused by the presence of neighbouring blade rows is investigated with the individual effects of wake, shock and potential field interaction being determined. Two test geometries are considered: first, a high-pressure turbine stage coupled with a swan-necked diffuser exit duct; secondly, the same high-pressure stage but with a vane located in the downstream duct. Both tests were conducted at engine-representative Mach and Reynolds numbers and experimental data was acquired using fast-response pressure transducers mounted on the mid-height streamline of the HP rotor blades. The results are compared to time-resolved computational predictions of the flowfield in order to aid interpretation of experimental results and to determine the accuracy with which the computation predicts blade interaction. In the first half of this paper it is shown that, in addition to the two main interaction mechanisms (upstream vane-rotor and rotor-downstream vane interactions, presented in Miller et al. [1]) a third interaction occurs. This new interaction mechanism is shown to be caused by the interaction between the downstream vane’s potential field and the upstream vane’s trailing edge potential field and shock. The unsteady rotor surface static pressure fluctuations caused by this interaction are shown to occur on the late rotor suction surface at a frequency corresponding to the difference in the numbers of upstream and downstream vanes. The second part to the paper discusses the mechanisms that cause vane-rotor-vane interaction. The rotor’s operating point is periodically altered as it passes the downstream vane. It is shown that for a large downstream vane, the flow conditions in the rotor passage, at any instant in time, are close to being steady state.

The composition of the time-resolved surface pressure field around a high-pressure rotor blade caused by the presence of neighboring blade rows is investigated, with the individual effects of wake, shock and potential field interaction being determined. Two test geometries are considered: first, a high-pressure turbine stage coupled with a swan-necked diffuser exit duct; secondly, the same high-pressure stage but with a vane located in the downstream duct. Both tests were conducted at engine-representative Mach and Reynolds numbers, and experimental data was acquired using fast-response pressure transducers mounted on the mid-height streamline of the HP rotor blades. The results are compared to time-resolved computational predictions of the flowfield in order to aid interpretation of experimental results and to determine the accuracy with which the computation predicts blade interaction. The paper is split into two parts, the first investigating the effect of the upstream vane on the unsteady pressure field around the rotor (vane-rotor interaction) and the second investigating the effect of the downstream vane on the unsteady pressure field around the rotor (rotor-vane interaction). The paper shows that at typical design operating conditions shock interaction from the upstream blade row is an order of magnitude greater than wake interaction and that with the design vane-rotor inter-blade gap the presence of the rotor causes a periodic increase in the strength of the vane trailing edge shock. The presence of the potential field of the downstream vane is found to affect significantly the rotor pressure field downstream of the Mach one surface within each rotor passage.

Newcastle Disease Virus Vaccine (MTH-68/H) was administered to patients suffering from advanced neoplastic diseases after non-efficient tumor-destructive treatment. Case reports of selected patients suggest promising effects of this treatment. A prospectively-randomized clinical study (phase III; in accordance with Good Clinical Practice, GCP) was proposed to confirm these results and is currently under consideration.

Recently, an energetic film growth technique was developed. In this process, an RF (radio frequency) plasma was ignited in an ambient atmospheric environment. An aqueous solution was excited into mist, which was then fed into the plasma reactor. After vaporization, films were formed on substrates outside the plasma. As a by-product, small amount of powders were collected in the plasma reactor. Films studied were indium-tin oxide (ITO), aluminum oxide (Al2O3), and lanthanum strontium manganite oxides (LaSrMnO). Films and powders were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX, EDS), and Ultraviolet-Visible (UV-Vis) transmission measurements. Morphology of a film surface was dependent on deposition conditions, such as chemical composition of the precursor materials, precursor feeding rate, and/or substrate temperature.

Cadmium Sulfide (CdS) thin films had been fabricated by a laser deposition technique. Our previous results indicated that the hexagonal structured films could be formed at a substrate temperature of 400 C or higher. Reducing the temperature to 200 C or lower, cubic dominant films had been fabricated. To further understand the effects of other deposition parameters, CdS films were deposited at 30 C in this study. Crystal structures of the films were analyzed by Xray diffraction (XRD) and Transmission Electron Microscopy (TEM). It was found that the processing windows for the cubic films were very limited. As revealed by optical transmission measurements, the optical absorption edge of the cubic film was different from that of the hexagonal film.

Indium tin oxide (ITO) thin films on soda-lime-silicate (SLS) and silica glasses were fabricated usingan RF plasma mist deposition process. SEM analysis showed that the ITO films consisted of uniformparticle size with a size ranging from 50 to 200 nm. XRD revealed that 1n203 phase is present in the filmwhen In : Sn ratio is 5 : 5 and higher. The resistivity of the ITO films was between 1-10 ohm-cm. Thestructural change near the surface of the glass was investigated by DRIFT (Diffuse reflectance infraredFourier transform) spectroscopy. The infrared results indicated that the structure near the surface wassignificantly changed with higher indium concentration. The coating materials create non-bridging oxygennear the surfaces. The effects of deposition time and substrate temperature were also studied.Key words: ITO, indium, tin, plasma, coating, glass, infrared, FTIR, surface. 2. INTRODUCTION Deposition techniques for transparent, conducting indium tin oxide (ITO) films include reactiveevaporation, chemical vapor deposition, spray pyrolysis, and RF magnetron sputtering.14 In this paper,we report an atmospheric deposition technique, an RF aerosol plasma deposition, to prepare the ITO filmson glasses. Applications of such coatings are conductive filters for use as shields against low frequencyinterference, flat panel liquid crystal displays, anti-static packaging, heat reflector, resistive heaters to

Thin-films of indium-tin oxide (ITO) on soda-lime-silicate (SLS) glass were fabricated using an atmospheric RF plasma mist deposition process. Some of the films were deposited at substrate temperatures between 400 C and 500 C, and were subsequently annealed at 400 C and 530 C for 1 hour. Conductivity was improved due to post-annealing. Film thickness, particle size, film morphology and crystallite size were characterized. The structural changes on the glass and the ITO film were investigated by DRIFT spectroscopy.

The effects of free-stream turbulence scale on heat transfer through a turbulent flat plate boundary layer have been measured. A variety of turbulence spectra were produced by parallel bar grids. The design of these was guided by previous measurements of combustion chamber turbulence. Heat transfer was measured transiently using thin film gauges. The heat transfer to the plate was found to be a function of turbulence integral length scale as well as intensity, and is of relevance to gas turbine heat transfer where aerofoils are subject to high turbulence levels from the combustor. Enhancement factors of up to 40% were experienced and the results extend conclusions drawn by other workers to higher turbulence levels and scales.Copyright © 1992 by ASME

Several 800 to 1100 μm thick films of oxygen‐free high‐conductivity (OFHC) copper and copper with additions of oxygen, krypton, silver, or yttrium were deposited at rates of 0.5 to 1.2 μm/min using an enhanced thermionically supported‐discharge (ETSD) sputtering apparatus. To obtain fine‐grained materials, several deposition parameters, such as partial pressure of oxygen in the sputtering gas, bias, and substrate temperature, were varied. Oxygen and krypton were incorporated by trapping the sputtering gas; silver and yttrium were added by means of the target design. The structures and microstructures were examined with standard x‐ray diffraction (XRD), transmission electron microscopy (TEM), and optical microscopy techniques. The grain sizes varied from 14 μm for the OFHC copper to 0.0073 μm for the Cu‐4 at. % Y deposits. XRD data indicated an amorphous structure for the Cu‐9 at. % Y deposits.

A study was made of crystallite orientation in cubic ferrites when pressed in a magnetic field. One easy axis orients in the field direction, the other easy axes lying at random in or near a perpendicular plane. Experimental torque curves have the theoretically predicted shape. The magnetic field required for microwave resonance is lower than in the same nonoriented ferrite if the axis of alignment and the field are parallel. This occurs because the anisotropy field Ha is no longer randomly oriented but helps to supply part of the resonant field requirement. Values of saturation magnetization (Ms), anisotropy energy (K), and resonant field (Hr) at 14 775 mc/sec were measured on a series of oriented polycrystalline nickel cobalt ferrites. Values of the measured resonant field are compared with values obtained from Kittel's resonance relation using the independently measured values of Ms and K.

Comparatively little work has been done on the topic of radiation damage in magnetic materials, and references concerning it will be cited herein only when pertinent to this paper. While our listing is limited, a bibliography of laboratory reports on the subject is available from the Battelle Memorial Institute. Much excellent engineering information and, in a few cases, some understanding of the mechanisms involved have grown out of the work which has been done, however, and our contribution is primarily an extension of previous investigations in the field to a few types of magnetic materials heretofore neglected.

A laser interferometer for earth strain measurements has been constructed and is described. The apparatus is designed to measure displacements down to small fractions of the laser wavelength. Measurements of length change of the interferometer arm of 10 m length were obtained during normal microseismic activity and following a distant earthquake. Some representative results of this laser application are presented.

The possibility of using a laser interferometer as a geophysical strainmeter was examined. A thermally stabilized laser was used and the results compared with a quartz Benioff strainmeter. From these measurements both long‐ and short‐term stability of the laser radiation were calculated. The results indicate that the long‐term stability is sufficient to observe earth tides while the short‐term stability is better than 1:1010.

A technique is described for the automatic measurement of ultrasonic velocity changes in continuous wave experiments. An oscillator is locked to a mechanical resonance of the sample. Velocity changes appear as frequency changes of the oscillator and are easily recorded. Some typical results are given.

The formation of yttrium iron garnet, Y3Fe2-(FeO4)3, starting with (1) Fe2O3 and Y2O3 and (2) Fe3O4 and Y2O3, was studied as a function of temperature and time by means of magnetic moment and X-ray measurements. The reaction began at 600°C. and was completed at 1200°C. The perovskite phase appeared only between 600° and 800°C. Above 1200°C. only the garnet phase was present. The microwave line width and g-factor at 9303 mc. per second were also measured and related to the preparation variables.

This paper describes an effort to determine control and display criteria for operating SAC's KC-135 tanker with a reduced crew complement. The Tanker Avionics and Aircrew Complement Evaluation (TAACE) Program was a four-phase effort addressing the control and display design issues associated with operating the tanker without the navigator position. Discussed are: the mission analysis phase, during which the tanker's operational responsibilities were defined and documented; the design phase, during which alternative crew station design concepts were developed; the mockup evaluation phase, which accomplished initial SAC crew member assessment of cockpit designs; and the simulation phase, which validated the useability of the crew system redesign. The paper also describes a recommended crew station configuration and discusses some of the philosophy underlying the selection of cockpit hardware and systems.

Effort is devoted to the measurement of acoustic losses in solids, primarily single crystals, at ultrasonic frequencies. In this type of experiment a pulse of r-f energy excites a quartz transducer bonded to the sample which in turn sends a pulse of ultrasound through the sample. The acoustic pulse is reflected from the sample end, travels back to the transducer and the reciprocal effect occurs. As a basic unit for this measurement the Sperry Ultrasonic Attenuation Comparator is used. This unit is a combination transmitter-receiver capable of delivering rf pulses over the frequency range 10-200 mc, containing a 60 mc meterodyne receiver with 8 mc bandwidth, and a calibrated exponential wave generator for attenuation measurements. The attenuation is essentially the logarithm of the ratio of the amplitudes of any two echoes, the procedure is to choose two convenient ones, detect their peaks, logarithmically amplify these, and then take the difference which is plotted on the x-y plotter against the suitable parameter.

An experimental study was performed to determine if spurious products formed from multiple signal mixes were dependent upon input signal phase relationships, and if the phase position of the intermediate frequency response wa s a function of mixer bias voltages. Formations of multiple mix products due to signal and local oscillator harmonic injection were investigated using a diode mixer, and the measurement procedures and instrumentation necessary to measure the effects of signal phase relationships on these products are presented. Test results are shown which verify that variations in the phase orientations between the fundamental and harmonics of an injected signal cause radical variations in output response levels. It is also shown that the phase of output responses are a function of the mixer bias voltage.

It is the intent of this paper to present both a broad overview of the total field of interference prediction and an analysis of past and current results obtained from specific prediction efforts. The broad overview portion of the paper consists largely of a discussion of the philosophy and purpose behind interference prediction efforts. The format of this overview will be an analysis of current system and equipment level problem areas conducted to establish (1) the areas in which interference predictions provide useful results, (2) why such predictions are necessary, (3) the primary objectives of interference prediction efforts, (4) the major factors involved in constructing accurate prediction models, and (5) the need for evaluation efforts to support prediction results. An analysis of past and current interference prediction efforts will be presented from a critical, but constructive, point of view. The efforts analyzed will include those intended to model equipment emissions and susceptibility thresholds based on limited spectrum signature data; system models involving a source, antenna, propagation factors, siting effects, and a receptor; environmental models concerned with relatively large geographical areas populated with many emitter-receptor combinations; etc. Based on the purpose, objective, and need for interference prediction in a broad sense and the detailed analysis of specific prediction efforts, needed developments, and improvements for the future are presented.

The Mossbauer study of stoichiometric Ni/sub 3/Mn shows that the transformation from the disordered to the ordered state proceeds by the classical first-order nucleation and growth process. Some Ni-Mn alloys are ferromagnetic in the ordered state and weakly ferromagnetic, or paramagnetic, in the disordered state. The difference is most pronounced near the composition Ni/sub 3/Mn. The samples were partially ordered by annealing in a helium atmosphere at 450 nif- C for 10 days. The spectrum left no doubt as to the transformation process. (C.E.S.)

A tilted loop technique has been developed to reduce bearing errors in loop HF directionfinder systems used on ionospherically propagated signals. Measures of signal elevation angle-of-arrival can be obtained. Theory of operation is stated. Field tests of an experimental model have verified the theory and disclosed significant improvements over a contemporary system.

Ultrasonic attenuation and velocity measurements exhibit anomalous peaks in the region of critical‐point transformations. Measurements near the Neel point (67.3°K) in MnF2 show such anomalous behavior with temperature. A large peak in the attenuation is observed over about a 2°–3°K temperature range with its maximum occurring at the Neel point. This peak has been studied over a frequency range from 10–150 MHz. The attenuation maximum is not seen with shear waves. Recently, we have been able to observe a similar anomaly in the velocity behavior of this material using a sensitive mechanical resonance technique. Both the attenuation and velocity data show anisotropy with the change in the (001) direction about 3 times that in the (110). These measurements, as well as results from other investigators, are discussed in terms of current theories.