Solid state microelectronics tolerant to radiation and high temperature

The 300 C electronics technology based on JFET thick film hybrids was tested up to 10 to the 9th power rad gamma (Si) and 10 to the 15th power neutrons/sq cm. Circuits and individual components from this technology all survived this total dose although some devices required 1 hour of annealing at 200 or 300 C to regain functionality. This technology used with real time annealing should function to levels greater than 10 to the 10th power rad gamma and 10 to the 16th power n/sq cm

Investigation of the effects of a moving acoustic medium on jet noise measurements

Noise from an unheated sonic jet in the presence of an external flow is measured in a free-jet wind tunnel using microphones located both inside and outside the flow. Comparison of the data is made with results of similar studies. The results are also compared with theoretical predictions of the source strength for jet noise in the presence of flow and of the effects of sound propagation through a shear layer

Development of On-Line NDE for the Continuous Resin Transfer Molding (CRTM)™ Process

The principal MDA task under the Affordable Polymeric Composite Material, Synthesis, and Processing program was the development and implementation of in- process nondestructive evaluation (NDE). The goals of the NDE effort were to: (1) develop an on-line ultrasonic scanning method for the CRTM™ process; (2) demonstrate the feasibility of the approach on a fabricated structure; and (3) incorporate the on-line ultrasonic system into the CRTM™ production line for long-term evaluation of the process during actual fabrication. The cost of NDE is significant for a composite structure fabricated by the hand layup – autoclave process, depending on the complexity of the structure. In addition to the labor required to accomplish the inspection, the part must be removed from the manufacturing flow and transported both to and from an offline inspection facility. A continuous fabrication process such as CRTM™ allows the incorporation of an inspection system directly into the processing line. Significant cost reductions are achievable by performing continuous and simultaneous inspection of composite structures as they are fabricated

A Rock Evaluation Schema for Transporting Planning in Kentucky

The initial goal was to devise an engineering classification system for intact rock samples based on simple index tests which could be used to categorize Kentucky surface and near-surface rock types and assist Kentucky Department of Transportation personnel in planning for transportation facilities. While conducting the literature survey, several facts become apparent: a large number of rock classification systems, geologic and technical, general and specific, already existed; an equally large number of index tests had been devised; and there was a lack of communication among those involved in specialized areas of rock-related work (geologists, civil engineers, mining engineers, etc.), and, to some extent, among individuals within each field. It was evident from a careful study of existing classification systems and index testing procedures that developing yet another specialized classification system with associated index tests would not be a significant contribution. It was decided, therefore, to concentrate on development of an overall rock evaluation schema which, while useful for a specific purpose, would avoid the undesirable disparate characteristics of narrowness or over-generalization prevalent in many classification systems. It was desired also to develop the program format in such a way that accumulated information could be systematically stored for easy access and use. It was apparent that full development and implementation of a program of this nature would require years of further studies and cooperation of many individuals and organizations. Such a program, properly developed and used, would substantially contribute to an advancement and a delineation of the schema and guidelines for its implementation would be a worthy goal

Searching for the most powerful thermonuclear X-ray bursts with the Neil Gehrels Swift Observatory

We searched for thermonuclear X-ray bursts from Galactic neutron stars in all event mode data of the Neil Gehrels Swift Observatory collected until March 31, 2018. In particular, we are interested in the intermediate-duration bursts (shell flashes fueled by thick helium piles) with the ill-understood phenomenon of strong flux fluctuations. Nine such bursts have been discussed in the literature to date. Swift is particularly suitable for finding additional examples. We find and list a total of 134 X-ray bursts; 44 are detected with BAT only, 41 with XRT only, and 49 with both. Twenty-eight bursts involve automatic slews. We find 12 intermediate-duration bursts, all detected in observations involving automatic slews. Five show remarkably long Eddington-limited phases in excess of 200 s. Five show fluctuations during the decay phase; four of which are first discussed in the present study. We discuss the general properties of the fluctuations, considering also 7 literature cases. In general two types of fluctuations are observed: fast ones, with a typical timescale of 1 s and up and downward fluctuations of up to 70%, and slow ones, with a typical timescale of 1 min and only downward fluctuations of up to 90%. The latter look like partial eclipses because the burst decay remains visible in the residual emission. We revisit the interpretation of this phenomenon in the context of the new data set and find that it has not changed fundamentally despite the expanded data set. It is thought to be due to a disturbance of the accretion disk by outflowing matter and photons, causing obscuration and reflection due to Thompson scattering in an orbiting highly ionized cloud or structure above or below the disk. We discuss in detail the most pronounced burster SAX J1712.6-3739. One of the bursts from this source is unusual in that it lasts longer than 5600 s, but does not appear to be a superburst.Comment: Accepted for publication in Astronomy & Astrophysics, 29 pages, 12 figures. Version 2 has 3 bursts from IGR J17480-2446 re-identified to 2 from Swift J174805.3-244637 and 1 from EXO 1745-24

A New Type of Photoelectric Colorimeter

A photoelectric colorimeter has been constructed which is capable of detecting small changes in the color of meat. With this apparatus it was possible to measure the variation in the color of meat as a function of the time of exposure to the air. The effects of temperature upon the color variation were also measured; and some data has been obtained showing the relation between the color and the grade of the meat

Strongly-coupled quantum critical point in an all-in-all-out antiferromagnet

Dimensionality and symmetry play deterministic roles in the laws of Nature. They are important tools to characterize and understand quantum phase transitions, especially in the limit of strong correlations between spin, orbit, charge, and structural degrees of freedom. Using newly-developed, high-pressure resonant x-ray magnetic and charge diffraction techniques, we have discovered a quantum critical point in Cd2Os2O7 as the all-in-all-out (AIAO) antiferromagnetic order is continuously suppressed to zero temperature and, concomitantly, the cubic lattice structure continuously changes from space group Fd-3m to F-43m. Surrounded by three phases of different time reversal and spatial inversion symmetries, the quantum critical region anchors two phase lines of opposite curvature, with striking departures from a mean-field form at high pressure. As spin fluctuations, lattice breathing modes, and quasiparticle excitations interact in the quantum critical region, we argue that they present the necessary components for strongly-coupled quantum criticality in this three-dimensional compound