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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The drilling of deep holes by means of gun drills is investigated so as to establish the parameters of the guide hole and its production. The rate of change in the load on the tool is proportional to the active length of the primary cutting edge. Assessment of the smoothness of tool insertion on the basis of the rate of change in the load on the tool is proposed.
The temperature dependence of the electromagnetic properties of hard tool alloys is studied experimentally. Temperature intervals corresponding to maximum alloy performance are identified. A method is proposed for determining the maximum-performance temperature of hard-alloy cutting inserts from the temperature dependence of the electromagnetic properties.
The design of tools with adjustable geometry is analyzed. A design is proposed for a boring tool with a replaceable polyhedral insert in which the lead angle may be varied. This design permits the machining of blind and through holes in the workpiece with the same cutter.
The height of the surface microrelief is determined for complex components in turning by a disk mill with a replaceable polyhedral insert. The influence of the cutting conditions and tool geometry on the microrelief is investigated.
Conversion-type electrode materials for lithium-ion batteries experience significant structural changes during the first discharge–charge cycle, where a single particle is taken apart into a number of nanoparticles. This structural evolution may affect the following lithium insertion reactions; however, how lithiation occurs in pre-cycled electrode materials is elusive. In this work, in situ transmission electron microscopy was employed to see the lithium-induced structural and chemical evolutions in pre-cycled nickel oxide as a model system. The introduction of lithium ions induced the evolution of metallic nickel, with volume expansion as a result of a conversion reaction. After pre-cycling, the phase evolutions occurred in two separate areas almost at the same time. This is different from the first lithiation, where the phase change takes place successively, with a boundary dividing the reacted and unreacted areas. Structural changes were restricted at the areas having large amount of fluorine, implying the residuals from the decomposition of electrolytes may have hindered the electrochemical reactions. This work provides insights into phase and chemical evolutions in pre-cycled conversion-type materials, which govern electrochemical properties during operation.
Low insertion loss, capacitively scanned goniometer for faraday rotation in very high frequency range
Faraday rotation measurements in the vhf range are made using a low-insertion goniometer with capacitive scanning
An improved test method accurately measures the insertion loss of RF components while avoiding amplifier drift. Currents are balanced across a bridge transformer with shorted probes and then with each component to be tested. Differences in adjustments indicate the loss.
Pressure molding tungsten microspheres is accomplished by applying hydraulic pressure to a silicone rubber mold insert with several barrel shaped chambers which is placed in a steel die cavity. This technique eliminates castings containing shear fractures.
Rack mounted chassis units are quickly inserted or extracted by a device which is driven in either direction by turning a simple hand crank. This device is used in aircraft and water craft.
Precision microwave insertion loss measurement using AC ratio transformer technique
Precision dc potentiometer microwave insertion loss test set for calibrating low noise microwave receiving systems used in space communications
Precision DC potentiometer microwave test set for coaxial or waveguide insertion loss measurement
Functional requirements for man-machine dialogue, noting voice insertion of data
Precision DC potentiometer test for measuring microwave coaxial or waveguide insertion loss
Aerial-image unit makes it possible to insert diagrams and animation into live motion pictures, and also lift an element from a confusing background by suppressing general details. The unit includes a combination of two separate lens systems, the camera-projector system and the field lens system.
Hand-operated plug insertion valve seals an evacuated insulation system for upper stage liquid hydrogen tanks on the launch pad. It is light in weight, demountable, and permits evacuation of the system plus sealing after evacuation.
Gnotobiotic insertion technique reliability in spacecraft sterilization applications