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Control of Carbon Nanotube Density and Tower Height in an Array

Applications include high-density semiconductor chips, and heat dissipation and thermal conduction in personal computers, smartphones, and televisions. Ames Research Center, Moffett Field, California Use of arrays of carbon nanotubes (CNTs) as an intermediary for transport of electrical particles (e.g., electrons) and/or transport of thermal energy from one body to another has grown. For example, a CNT array may be used for dissipation of thermal energy or accumulated electrical charge associated with operation of an electronics device or system. However, the device or system may require use of different CNT array densities in various regions because of differing transport requirements.

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In-Situ Chemical Analysis of Material Surfaces

Composition by freezing uses laser ablation and laser ionization mass spectrometry for detection of chemical, pharmaceutical, biotech, and hazardous materials. NASA’s Jet Propulsion Laboratory, Pasadena, California In order to understand whether the ablation laser would cause chemical reactions within the trapped organic molecules during resonant laser ablation of water ice containing organic molecules, a two-layer approach was devised. The first layer consisted of D2O ice containing organics that are inactive for the laser wavelength used (2.94 microns), and shown not to ablate under these conditions. When an additional layer of H2O ice was deposited on top of the D2O layer, both H2O and D2O layers, and the organics embedded in the D2O layer, became ablated due to resonant excitation of the H2O ice layer that transferred energy to the D2O layer. This showed that the organic matter is not damaged.

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Ratcheting Threaded Tapered Collet for use in Planetary Sample Caching Systems

The desired sample tube preload can be tailored to specific applications, and allows each sample to be individually secured. NASA’s Jet Propulsion Laboratory, Pasadena, California Aridged retention interface is necessary to secure planetary sample tubes within a caching system for use in future sample return missions. The assumed retention interface requirements are as follows: the interface shall maintain sample integrity at large deceleration landing loads; the interface shall minimize weight and complexity; and any required actuation for sample tube retention shall be performed by an external source (such as a robotic end-effector).

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Planetary Ice Mining by Down-Hole Energy Injection

This lightweight technology operates in low gravity with energy efficiency. John F. Kennedy Space Center, Florida Ice has been discovered on Mars and is present in the permanently shadowed craters on the Moon and on many asteroids. The ice is usually buried beneath an overburden of regolith. Evidence indicates this overburden may be a meter deep in some locations for the Moon; for Mars, it varies with latitude and may be as deep as or deeper than two meters in many locations. To obtain this ice as a resource in usable quantities, existing technology will require that it be strip-mined.

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Laser Architecture and Atomic Filter for Daytime Measurements Using Spaceborne Sodium Lidar

Goddard Space Flight Center, Greenbelt, Maryland A satellite-borne sodium lidar will provide key measurements that elucidate the complex relation between the chemistry and dynamics of the Earth’s mesosphere, and thus provide a thorough understanding of the composition and dynamics of this region. The inclusion of a well-characterized mesosphere in global models is essential for weather and climate prediction in the lower atmosphere. It also will help to elucidate the complex vertical coupling processes through which atmospheric weather affects space weather. Furthermore, once the technique is developed, it can be used to study the composition of other planetary atmospheres, which is identified as a key point in the recent Planetary Decadal Survey.

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Rangefinder for Measuring Volume of Cryogenic or Caustic Turbulent Fluids

A non-intrusive laser rangefinder yields extremely accurate fluid height measurements. Stennis Space Center, Mississippi Specific impulse (ISP), or simply impulse (change in momentum) per unit amount of propellant consumed, is a measure of rocket and jet engine efficiency. The amount of propellant, or in the case of engine testing at the Stennis Space Center (SSC), cryogen consumed during rocket engine testing must be measured to accurately quantify ISP. One way to determine the amount of cryogen used is to measure the change in cryogen fluid height within a storage/feed tank during testing and then relate the change in height to volume of cryogen consumed. A float system coupled with discrete vertically positioned Reed switches is currently used at the SSC to determine cryogen fluid height and then determine cryogen consumed during a rocket motor test firing. However, the cryogen fluid level within a run tank varies continuously and the switches are placed at discrete locations, limiting the accuracy of this method. If individual switch failures occur, the error increases due to the increased distance between switches/measurement locations. In addition, since pressurized gas is used to force the significantly cooler liquid cryogen out of the tank during a test, the liquid cryogen surface is turbulent and not flat or smooth, which can also affect accuracy.

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Micro-Force Sensing Nanoprobe

Goddard Space Flight Center, Greenbelt, Maryland The NGXO (Next Generation X-Ray Optics) project has several problems relating to how to bond a very thin glass mirror to a metallic structure without distortion. One problem is that all epoxies shrink (at the micron level) when they cure. This shrinkage distorts the optical quality of the mirror unacceptably. Another problem is how to correlate finite element models of thin glass mirrors to verify that they are accurately predicting the distortions that a real glass will see due to enforced displacements, such as those applied by epoxy shrinkage. The forces required to simulate epoxy shrinkage and to balance a mirror on a bed of actuators are in the 100-1000 micro-newton range. The displacements are on the order of a few microns. These tiny forces and displacements cannot be easily measured or actuated with typical lab equipment.

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