Burying by rats in response to aversive and nonaversive stimuli

PubMed Central

Poling, Alan; Cleary, James; Monaghan, Michael

1981-01-01

Previous investigations have shown that rats bury a variety of conditioned and unconditioned aversive stimuli. Such burying has been considered as a species-typical defensive reaction. In the present studies, rats buried spouts filled with Tabasco sauce, or condensed milk to which a taste aversion was conditioned, but did not bury water-filled spouts or spouts filled with a palatable novel food (apple juice) to which a taste aversion was not conditioned. However, in other experiments rats consistently and repeatedly buried Purina Rat Chow, Purina Rat Chow coated with quinine, and glass marbles. This indicates that a variety of stimuli, not all aversive or novel, evoke burying by rats. Whereas the behavior may reasonably be considered as a species-typical defensive behavior in some situations, the wide range of conditions that occasion burying suggests that the behavior has no single biological function. PMID:16812198

System and method for removal of buried objects

DOEpatents

Alexander, Robert G [Richland, WA; Crass, Dennis [Kennewick, WA; Grams, William [Kennewick, WA; Phillips, Steven J [Sunnyside, WA; Riess, Mark [Kennewick, WA

2008-06-03

The present invention is a system and method for removal of buried objects. According to one embodiment of the invention, a crane with a vibrator casing driver is used to lift and suspend a large diameter steel casing over the buried object. Then the casing is driven into the ground by the vibratory driver until the casing surrounds the buried object. Then the open bottom of the casing is sealed shut by injecting grout into the ground within the casing near its bottom. When the seal has cured and hardened, the top of the casing is lifted to retrieve the casing, with the buried object inside, from the ground.

Finite Element Modeling and Long Wave Infrared Imaging for Detection and Identification of Buried Objects

DTIC Science & Technology

surface temperature profile of a sandbox containing buried objects using a long-wave infrared camera. Images were recorded for several days under ambient...time of day . Best detection of buried objects corresponded to shallow depths for observed intervals where maxima/minima ambient temperatures coincided

Buried Object Detection Method Using Optimum Frequency Range in Extremely Shallow Underground

NASA Astrophysics Data System (ADS)

Sugimoto, Tsuneyoshi; Abe, Touma

2011-07-01

We propose a new detection method for buried objects using the optimum frequency response range of the corresponding vibration velocity. Flat speakers and a scanning laser Doppler vibrometer (SLDV) are used for noncontact acoustic imaging in the extremely shallow underground. The exploration depth depends on the sound pressure, but it is usually less than 10 cm. Styrofoam, wood (silver fir), and acrylic boards of the same size, different size styrofoam boards, a hollow toy duck, a hollow plastic container, a plastic container filled with sand, a hollow steel can and an unglazed pot are used as buried objects which are buried in sand to about 2 cm depth. The imaging procedure of buried objects using the optimum frequency range is given below. First, the standardized difference from the average vibration velocity is calculated for all scan points. Next, using this result, underground images are made using a constant frequency width to search for the frequency response range of the buried object. After choosing an approximate frequency response range, the difference between the average vibration velocity for all points and that for several points that showed a clear response is calculated for the final confirmation of the optimum frequency range. Using this optimum frequency range, we can obtain the clearest image of the buried object. From the experimental results, we confirmed the effectiveness of our proposed method. In particular, a clear image of the buried object was obtained when the SLDV image was unclear.

Lateral uniformity in chemical composition along a buried reaction front in polymers using off-specular reflectivity.

PubMed

Lavery, Kristopher A; Prabhu, Vivek M; Satija, Sushil; Wu, Wen-Li

2010-12-01

Off-specular neutron reflectometry was applied to characterize the form and amplitude of lateral compositional variations at a buried reaction-diffusion front. In this work, off-specular neutron measurements were first calibrated using off-specular x-ray reflectivity and atomic force microscopy via a roughened glass surface, both as a free surface and as a buried interface that was prepared by spin coating thin polymer films upon the glass surface. All three methods provided consistent roughness values despite the difference in their detection mechanism. Our neutron results demonstrated, for the first time, that the compositional heterogeneity at a buried reaction front can be measured; the model system used in this study mimics the deprotection reaction that occurs during the photolithographic process necessary for manufacturing integrated circuits.

Distinguishing Buried Objects in Extremely Shallow Underground by Frequency Response Using Scanning Laser Doppler Vibrometer

NASA Astrophysics Data System (ADS)

Abe, Touma; Sugimoto, Tsuneyoshi

2010-07-01

A sound wave vibration using a scanning laser Doppler vibrometer are used as a method of exploring and imaging an extremely shallow underground. Flat speakers are used as a vibration source. We propose a method of distinguishing a buried object using a response range of a frequencies corresponding to a vibration velocities. Buried objects (plastic containers, a hollow steel can, an unglazed pot, and a stone) are distinguished using a response range of frequencies. Standardization and brightness imaging are used as methods of discrimination. As a result, it was found that the buried objects show different response ranges of frequencies. From the experimental results, we confirmed the effectiveness of our proposed method.

Road detection and buried object detection in elevated EO/IR imagery

NASA Astrophysics Data System (ADS)

Kennedy, Levi; Kolba, Mark P.; Walters, Joshua R.

2012-06-01

To assist the warfighter in visually identifying potentially dangerous roadside objects, the U.S. Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD) has developed an elevated video sensor system testbed for data collection. This system provides color and mid-wave infrared (MWIR) imagery. Signal Innovations Group (SIG) has developed an automated processing capability that detects the road within the sensor field of view and identifies potentially threatening buried objects within the detected road. The road detection algorithm leverages system metadata to project the collected imagery onto a flat ground plane, allowing for more accurate detection of the road as well as the direct specification of realistic physical constraints in the shape of the detected road. Once the road has been detected in an image frame, a buried object detection algorithm is applied to search for threatening objects within the detected road space. The buried object detection algorithm leverages textural and pixel intensity-based features to detect potential anomalies and then classifies them as threatening or non-threatening objects. Both the road detection and the buried object detection algorithms have been developed to facilitate their implementation in real-time in the NVESD system.

Buried nonmetallic object detection using bistatic ground penetrating radar with variable antenna elevation angle and height

NASA Astrophysics Data System (ADS)

Zhang, Yu; Orfeo, Dan; Burns, Dylan; Miller, Jonathan; Huston, Dryver; Xia, Tian

2017-04-01

Ground penetrating radar (GPR) has been shown to be an effective device for detecting buried objects that have little or no metal content, such as plastic, ceramic, and concrete pipes. In this paper, buried non-metallic object detection is evaluated for different antenna elevation angles and heights using a bistatic air-launched GPR. Due to the large standoff distance between antennas and the ground surface, the air-launched GPR has larger spreading loss than the hand-held GPR and vehicle-mounted GPR. Moreover, nonmetallic objects may have similar dielectric property to the buried medium, which results in further difficulty for accurate detection using air-launched GPR. To study such effects, both GPR simulations and GPR laboratory experiments are performed with various setups where antennas are placed at different heights and angles. In the experiments, the test surface areas are configured with and without rocks in order to examine surface clutter effect. The experimental results evaluate the feasibility and effectiveness of bistatic air-launched GPR for detecting buried nonmetallic objects, which provide valuable insights for subsurface scanning with unmanned aerial vehicle (UAV) mounted GPR.

Mechanical Energy Propagation and Backscattering in Nominally Dry Soil: Imaging Buried Land Mines

NASA Astrophysics Data System (ADS)

Sen, Surajit

2003-04-01

The imaging of shallow buried objects in a complex medium, e.g., nominally dry sand, is an outstanding challenge. Such imaging is of relevance in connection with the detection and subsequent imaging of buried non-metallic anti-personnel land mines and in other applications. It has been shown that gentle mechanical impulses and low frequency sound waves with frequencies roughly between 150-350 Hz or so can penetrate distances of up to a foot in sand. Hence, such signals can potentially be useful in the detection and perhaps in the imaging of shallow buried objects. It is presently unclear whether high frequency signals can be effectively used to image shallow buried objects. Impulses can typically penetrate larger distances into sand and soil. Both impulses and continuous sound waves can be used for imaging shallow buried objects. The talk shall briefly review the state-of-the-art in low frequency sound propagation in soil and shall discuss the current understanding of impulse propagation and backscattering in nominally dry sand beds. It will be argued that impulse based imaging may have the potential to be a simple and fast way to detect and image small non-metallic mines. Research supported by the National Science Foundation Grant No. NSF-CMS 0070055.

Comparison of experimental three-band IR detection of buried objects and multiphysics simulations

NASA Astrophysics Data System (ADS)

Rabelo, Renato C.; Tilley, Heather P.; Catterlin, Jeffrey K.; Karunasiri, Gamani; Alves, Fabio D. P.

2018-04-01

A buried-object detection system composed of a LWIR, a MWIR and a SWIR camera, along with a set of ground and ambient temperature sensors was constructed and tested. The objects were buried in a 1.2x1x0.3 m3 sandbox and surface temperature (using LWIR and MWIR cameras) and reflection (using SWIR camera) were recoded throughout the day. Two objects (aluminum and Teflon) with volume of about 2.5x10-4 m3 , were placed at varying depths during the measurements. Ground temperature sensors buried at three different depths measured the vertical temperature profile within the sandbox, while the weather station recorded the ambient temperature and solar radiation intensity. Images from the three cameras were simultaneously acquired in five-minute intervals throughout many days. An algorithm to postprocess and combine the images was developed in order to maximize the probability of detection by identifying thermal anomalies (temperature contrast) resulting from the presence of the buried object in an otherwise homogeneous medium. A simplified detection metric based on contrast differences was established to allow the evaluation of the image processing method. Finite element simulations were performed, reproducing the experiment conditions and, when possible, incorporated with data coming from actual measurements. Comparisons between experiment and simulation results were performed and the simulation parameters were adjusted until images generated from both methods are matched, aiming at obtaining insights of the buried material properties. Preliminary results show a great potential for detection of shallowburied objects such as land mines and IEDs and possible identification using finite element generated maps fitting measured surface maps.

Buried object remote detection technology for law enforcement

NASA Astrophysics Data System (ADS)

del Grande, Nancy K.; Clark, Gregory A.; Durbin, Philip F.; Fields, David J.; Hernandez, Jose E.; Sherwood, Robert J.

1991-08-01

A precise airborne temperature-sensing technology to detect buried objects for use by law enforcement is developed. Demonstrations have imaged the sites of buried foundations, walls and trenches; mapped underground waterways and aquifers; and been used to locate underground military objects. The methodology is incorporated in a commercially available, high signal-to-noise, dual-band infrared scanner with real-time, 12-bit digital image processing software and display. The method creates color-coded images based on surface temperature variations of 0.2 degree(s)C. Unlike other less-sensitive methods, it maps true (corrected) temperatures by removing the (decoupled) surface emissivity mask equivalent to 1 degree(s)C or 2 degree(s)C; this mask hinders interpretation of apparent (blackbody) temperatures. Once removed, it is possible to identify surface temperature patterns from small diffusivity changes at buried object sites which heat and cool differently from their surroundings. Objects made of different materials and buried at different depths are identified by their unique spectral, spatial, thermal, temporal, emissivity and diffusivity signatures. The authors have successfully located the sites of buried (inert) simulated land mines 0.1 to 0.2 m deep; sod-covered rock pathways alongside dry ditches, deeper than 0.2 m; pavement covered burial trenches and cemetery structures as deep as 0.8 m; and aquifers more than 6 m and less than 60 m deep. The technology could be adapted for drug interdiction and pollution control. For the former, buried tunnels, underground structures built beneath typical surface structures, roof-tops disguised by jungle canopies, and covered containers used for contraband would be located. For the latter, buried waste containers, sludge migration pathways from faulty containers, and the juxtaposition of groundwater channels, if present, nearby, would be depicted. The precise airborne temperature-sensing technology has a promising potential to detect underground epicenters of smuggling and pollution.

Buried object remote detection technology for law enforcement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Del Grande, N.K.; Clark, G.A.; Durbin, P.F.

1991-03-01

We have developed a precise airborne temperature-sensing technology to detect buried objects for use by law enforcement. Demonstrations have imaged the sites of buried foundations, walls and trenches; mapped underground waterways and aquifers; and been used to locate underground military objects. Our patented methodology is incorporated in a commercially available, high signal-to-noise, dual-band infrared scanner with real-time, 12-bit digital image processing software and display. Our method creates color-coded images based on surface temperature variations of 0.2 {degrees}C. Unlike other less-sensitive methods, it maps true (corrected) temperatures by removing the (decoupled) surface emissivity mask equivalent to 1{degrees}C or 2{degrees}C; this maskmore » hinders interpretation of apparent (blackbody) temperatures. Once removed, were are able to identify surface temperature patterns from small diffusivity changes at buried object sites which heat and cool differently from their surroundings. Objects made of different materials and buried at different depths are identified by their unique spectra, spatial, thermal, temporal, emissivity and diffusivity signatures. We have successfully located the sites of buried (inert) simulated land mines 0.1 to 0.2 m deep; sod-covered rock pathways alongside dry ditches, deeper than 0.2 m; pavement covered burial trenches and cemetery structures as deep as 0.8 m; and aquifers more than 6 m and less 60 m deep. Our technology could be adapted for drug interdiction and pollution control. 16 refs., 14 figs.« less

Shallow-Water Mud Acoustics

DTIC Science & Technology

2015-09-30

1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Shallow- Water Mud Acoustics William L. Siegmann...shallow water over mud sediments and of acoustic detection, localization, and classification of objects buried in mud. OBJECTIVES • Develop...including long-range conveyance of information; detection, localization, and classification of objects buried in mud; and improvement of shallow water

Sedimentary controls on modern sand grain coat formation

NASA Astrophysics Data System (ADS)

Dowey, Patrick J.; Worden, Richard H.; Utley, James; Hodgson, David M.

2017-05-01

Coated sand grains can influence reservoir quality evolution during sandstone diagenesis. Porosity can be reduced and fluid flow restricted where grain coats encroach into pore space. Conversely pore-lining grain coats can restrict the growth of pore-filling quartz cement in deeply buried sandstones, and thus can result in unusually high porosity in deeply buried sandstones. Being able to predict the distribution of coated sand grains within petroleum reservoirs is thus important to help find good reservoir quality. Here we report a modern analogue study of 12 sediment cores from the Anllóns Estuary, Galicia, NW Spain, collected from a range of sub-environments, to help develop an understanding of the occurrence and distribution of coated grains. The cores were described for grain size, bioturbation and sedimentary structures, and then sub-sampled for electron and light microscopy, laser granulometry, and X-ray diffraction analysis. The Anllóns Estuary is sand-dominated with intertidal sand flats and saltmarsh environments at the margins; there is a shallowing/fining-upwards trend in the estuary-fill succession. Grain coats are present in nearly every sample analysed; they are between 1 μm and 100 μm thick and typically lack internal organisation. The extent of grain coat coverage can exceed 25% in some samples with coverage highest in the top 20 cm of cores. Samples from muddy intertidal flat and the muddy saltmarsh environments, close to the margins of the estuary, have the highest coat coverage (mean coat coverage of 20.2% and 21.3%, respectively). The lowest mean coat coverage occurs in the sandy saltmarsh (10.4%), beyond the upper tidal limit and sandy intertidal flat environments (8.4%), close to the main estuary channel. Mean coat coverage correlates with the concentration of clay fraction. The primary controls on the distribution of fine-grained sediment, and therefore grain coat distribution, are primary sediment transport and deposition processes that concentrate the clay fraction in the sediment towards the margins of the estuary. Bioturbation and clay illuviation/mechanical infiltration are secondary processes that may redistribute fine-grained sediment and produce grain coats. Here we have shown that detrital grain coats are more likely in marginal environments of ancient estuary-fills, which are typically found in the fining-upward part of progradational successions.

Laser-induced acoustic imaging of underground objects

NASA Astrophysics Data System (ADS)

Li, Wen; DiMarzio, Charles A.; McKnight, Stephen W.; Sauermann, Gerhard O.; Miller, Eric L.

1999-02-01

This paper introduces a new demining technique based on the photo-acoustic interaction, together with results from photo- acoustic experiments. We have buried different types of targets (metal, rubber and plastic) in different media (sand, soil and water) and imaged them by measuring reflection of acoustic waves generated by irradiation with a CO2 laser. Research has been focused on the signal acquisition and signal processing. A deconvolution method using Wiener filters is utilized in data processing. Using a uniform spatial distribution of laser pulses at the ground's surface, we obtained 3D images of buried objects. The images give us a clear representation of the shapes of the underground objects. The quality of the images depends on the mismatch of acoustic impedance of the buried objects, the bandwidth and center frequency of the acoustic sensors and the selection of filter functions.

Numerical study of the polarization effect of GPR systems on the detection of buried objects

NASA Astrophysics Data System (ADS)

Sagnard, Florence

2017-04-01

This work is in line with the studies carried out in our department over the last few years on object detection in civil engineering structures and soils. In parallel to building of the second version of the Sense-City test site where several pipeline networks will be buried [1], we are developing numerical models using the FIT and the FDTD approaches to study more precisely the contribution of the polarization diversity in the detection of conductive and dielectric buried objects using the GPR technique. The simulations developed are based on a ultra-wide band SFCW GPR system that have been designed and evaluated in our laboratory. A parametric study is proposed to evaluate the influence of the antenna configurations and the antenna geometry when considering the polarization diversity in the detection and characterization of canonical objects. [1] http://www.sense-city.univ-paris-est.fr/index.php

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2011 CFR

2011-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2010 CFR

2010-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2014 CFR

2014-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2012 CFR

2012-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

49 CFR 195.569 - Do I have to examine exposed portions of buried pipelines?

Code of Federal Regulations, 2013 CFR

2013-10-01

... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.569 Do I have to examine... exposed, you must examine the exposed portion for evidence of external corrosion if the pipe is bare, or if the coating is deteriorated. If you find external corrosion requiring corrective action under...

Terahertz pulsed imaging as an advanced characterisation tool for film coatings--a review.

PubMed

Haaser, Miriam; Gordon, Keith C; Strachan, Clare J; Rades, Thomas

2013-12-05

Solid dosage forms are the pharmaceutical drug delivery systems of choice for oral drug delivery. These solid dosage forms are often coated to modify the physico-chemical properties of the active pharmaceutical ingredients (APIs), in particular to alter release kinetics. Since the product performance of coated dosage forms is a function of their critical coating attributes, including coating thickness, uniformity, and density, more advanced quality control techniques than weight gain are required. A recently introduced non-destructive method to quantitatively characterise coating quality is terahertz pulsed imaging (TPI). The ability of terahertz radiation to penetrate many pharmaceutical materials enables structural features of coated solid dosage forms to be probed at depth, which is not readily achievable with other established imaging techniques, e.g. near-infrared (NIR) and Raman spectroscopy. In this review TPI is introduced and various applications of the technique in pharmaceutical coating analysis are discussed. These include evaluation of coating thickness, uniformity, surface morphology, density, defects and buried structures as well as correlation between TPI measurements and drug release performance, coating process monitoring and scale up. Furthermore, challenges and limitations of the technique are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Buried nanoantenna arrays: versatile antireflection coating.

PubMed

Kabiri, Ali; Girgis, Emad; Capasso, Federico

2013-01-01

Reflection is usually a detrimental phenomenon in many applications such as flat-panel-displays, solar cells, photodetectors, infrared sensors, and lenses. Thus far, to control and suppress the reflection from a substrate, numerous techniques including dielectric interference coatings, surface texturing, adiabatic index matching, and scattering from plasmonic nanoparticles have been investigated. A new technique is demonstrated to manage and suppress reflection from lossless and lossy substrates. It provides a wider flexibility in design versus previous methods. Reflection from a surface can be suppressed over a narrowband, wideband, or multiband frequency range. The antireflection can be dependent or independent of the incident wave polarization. Moreover, antireflection at a very wide incidence angle can be attained. The reflection from a substrate is controlled by a buried nanoantenna array, a structure composed of (1) a subwavelength metallic array and (2) a dielectric cover layer referred to as a superstrate. The material properties and thickness of the superstrate and nanoantennas' geometry and periodicity control the phase and intensity of the wave circulating inside the superstrate cavity. A minimum reflectance of 0.02% is achieved in various experiments in the mid-infrared from a silicon substrate. The design can be integrated in straightforward way in optical devices. The proposed structure is a versatile AR coating to optically impedance matches any substrate to free space in selected any narrow and broadband spectral response across the entire visible and infrared spectrum.

Continued Investigation of the Acoustics of Marine Sediments Using Impedance Tube and Acoustic Resonator Techniques

DTIC Science & Technology

2009-09-30

seagrass , which in turn benefits buried object detection, sonar operation and acoustic communications in shallow water. Another goal for the out years...bottom sediments, including multiphase materials such as gas- bearing sediments and seagrass . These measurements are conducted using an acoustic...such as gas-bearing sediments and seagrass , which in turn benefits buried object detection, sonar operation and acoustic communications in shallow

Acoustic-based Technology to Detect Buried Pipes

DOT National Transportation Integrated Search

2011-07-29

The objective of this project is to build a pre-commercial device, improve its performance to detect multiple buried pipes, and evaluate the pre-commercial device at utility sites. In the past, Gas Technology Institute (GTI) and SoniVerse Inc. (SVI) ...

Self-healing coatings based on halloysite clay polymer composites for protection of copper alloys.

PubMed

Abdullayev, Elshad; Abbasov, Vagif; Tursunbayeva, Asel; Portnov, Vasiliy; Ibrahimov, Hikmat; Mukhtarova, Gulbaniz; Lvov, Yuri

2013-05-22

Halloysite clay nanotubes loaded with corrosion inhibitors benzotriazole (BTA), 2-mercaptobenzimidazole (MBI), and 2-mercaptobenzothiazole (MBT) were used as additives in self-healing composite paint coating of copper. These inhibitors form protective films on the metal surface and mitigate corrosion. Mechanisms involved in the film formation have been studied with optical and electron microscopy, UV-vis spectrometry, and adhesivity tests. Efficiency of the halloysite lumen loading ascended in the order of BTA < MBT < MBI; consequently, MBI and MBT halloysite formulations have shown the best protection. Inhibitors were kept in the tubes buried in polymeric paint layer for a long time and release was enhanced in the coating defects exposed to humid media with 20-50 h, sufficient for formation of protective layer. Anticorrosive performance of the halloysite-based composite acrylic and polyurethane coatings have been demonstrated for 110-copper alloy strips exposed to 0.5 M aqueous NaCl for 6 months.

Buried Object Detection

DTIC Science & Technology

1988-01-22

Final Report 19 January 1987 Army Research OfficeM Contract No. DAAL03..87-K-0052 National Center for Physical Acoustics D T ! C " Naioal P. 0. Box 847...black . umberJ FIELO I GROUP I SU9GROU-p Acoustic , Seismic, Acoustic seismic coupling, porefluid, pulse echo, propagation, soils, sound speed...seismic transfer function. /’An acoustic scheme for buried object detection is thought to involve a sound source above the ground and a microphone as a

Sequential feature selection for detecting buried objects using forward looking ground penetrating radar

NASA Astrophysics Data System (ADS)

Shaw, Darren; Stone, Kevin; Ho, K. C.; Keller, James M.; Luke, Robert H.; Burns, Brian P.

2016-05-01

Forward looking ground penetrating radar (FLGPR) has the benefit of detecting objects at a significant standoff distance. The FLGPR signal is radiated over a large surface area and the radar signal return is often weak. Improving detection, especially for buried in road targets, while maintaining an acceptable false alarm rate remains to be a challenging task. Various kinds of features have been developed over the years to increase the FLGPR detection performance. This paper focuses on investigating the use of as many features as possible for detecting buried targets and uses the sequential feature selection technique to automatically choose the features that contribute most for improving performance. Experimental results using data collected at a government test site are presented.

Preprocessing of A-scan GPR data based on energy features

NASA Astrophysics Data System (ADS)

Dogan, Mesut; Turhan-Sayan, Gonul

2016-05-01

There is an increasing demand for noninvasive real-time detection and classification of buried objects in various civil and military applications. The problem of detection and annihilation of landmines is particularly important due to strong safety concerns. The requirement for a fast real-time decision process is as important as the requirements for high detection rates and low false alarm rates. In this paper, we introduce and demonstrate a computationally simple, timeefficient, energy-based preprocessing approach that can be used in ground penetrating radar (GPR) applications to eliminate reflections from the air-ground boundary and to locate the buried objects, simultaneously, at one easy step. The instantaneous power signals, the total energy values and the cumulative energy curves are extracted from the A-scan GPR data. The cumulative energy curves, in particular, are shown to be useful to detect the presence and location of buried objects in a fast and simple way while preserving the spectral content of the original A-scan data for further steps of physics-based target classification. The proposed method is demonstrated using the GPR data collected at the facilities of IPA Defense, Ankara at outdoor test lanes. Cylindrically shaped plastic containers were buried in fine-medium sand to simulate buried landmines. These plastic containers were half-filled by ammonium nitrate including metal pins. Results of this pilot study are demonstrated to be highly promising to motivate further research for the use of energy-based preprocessing features in landmine detection problem.

High-performance continuous-wave room temperature 4.0-μm quantum cascade lasers with single-facet optical emission exceeding 2 W

PubMed Central

Lyakh, A.; Maulini, R.; Tsekoun, A.; Go, R.; Von der Porten, S.; Pflügl, C.; Diehl, L.; Capasso, Federico; Patel, C. Kumar N.

2010-01-01

A strain-balanced, AlInAs/InGaAs/InP quantum cascade laser structure, designed for light emission at 4.0 μm using nonresonant extraction design approach, was grown by molecular beam epitaxy. Laser devices were processed in buried heterostructure geometry. An air-cooled laser system incorporating a 10-mm × 11.5-μm laser with antireflection-coated front facet and high-reflection-coated back facet delivered over 2 W of single-ended optical power in a collimated beam. Maximum continuous-wave room temperature wall plug efficiency of 5.0% was demonstrated for a high-reflection-coated 3.65-mm × 8.7-μm laser mounted on an aluminum nitride submount.

Repair of a mirror coating on a large optic for high laser damage applications using ion milling and over-coating methods

NASA Astrophysics Data System (ADS)

Field, Ella S.; Bellum, John C.; Kletecka, Damon E.

2017-01-01

When an optical coating is damaged, deposited incorrectly, or is otherwise unsuitable, the conventional method to restore the optic often entails repolishing the optic surface, which can incur a large cost and long lead time. We propose three alternative options to repolishing, including (i) burying the unsuitable coating under another optical coating, (ii) using ion milling to etch the unsuitable coating completely from the optic surface and then recoating the optic, and (iii) using ion milling to etch through a number of unsuitable layers, leaving the rest of the coating intact, and then recoating the layers that were etched. Repairs were made on test optics with dielectric mirror coatings according to the above three options. The mirror coatings to be repaired were quarter wave stacks of HfO2 and SiO2 layers for high reflection at 1054 nm at 45 deg incidence in P-polarization. One of the coating layers was purposely deposited incorrectly as Hf metal instead of HfO2 to evaluate the ability of each repair method to restore the coating's high laser-induced damage threshold (LIDT) of 64.0 J/cm2. The repaired coating with the highest resistance to laser-induced damage was achieved using repair method (ii) with an LIDT of 49.0 to 61.0 J/cm2.

Evaluation of the use of shredded tires around buried pipes : technical assistance report.

DOT National Transportation Integrated Search

1999-05-01

The objective of this project was to assess the potential of placement and compaction of shredded tire chips and soil-tire mix in confined trenches around buried pipes and to evaluate the stability and deformation of metal pipes in such systems. The ...

Detecting Thermal Barrier Coating Delamination Using Visible and Near-Infrared Luminescence from Erbium-Doped Sublayers

NASA Technical Reports Server (NTRS)

Eldridge, J. I.; Bencic, T. J.; Martin, R. E.; Singh, J.; Wolfe, D. E.

2007-01-01

Nondestructive diagnostic tools are needed to monitor early stages of delamination progression in thermal barrier coatings (TBCs) because the risk of delamination induced coating failure will compromise engine performance and safety. Previous work has demonstrated that for TBCs composed of yttria-stabilized zirconia (YSZ), luminescence from a buried europium-doped sublayer can be utilized to identify the location of TBC delamination from the substantially higher luminescence intensity observed from the delaminated regions of the TBC. Luminescence measurements from buried europium-doped layers depend on sufficient transmittance of the 532 nm excitation and 606 nm emission wavelengths through the attenuating undoped YSZ overlayer to produce easily detected luminescence. In the present work, improved delamination indication is demonstrated using erbium-doped YSZ sublayers. For visible-wavelength luminescence, the erbium-doped sublayer offers the advantage of a very strong excitation peak at 517 nm that can be conveniently excited a 514 nm Ar ion laser. More importantly, the erbium-doped sublayer also produces near-infrared luminescence at 1550 nm that is effectively excited by a 980 nm laser diode. Both the 980 nm excitation and the 1550 nm emission are transmitted through the TBC with much less attenuation than visible wavelengths and therefore show great promise for delamination monitoring through thicker or more highly scattering TBCs. The application of this approach for both electron beam physical vapor deposited (EB-PVD) and plasma-sprayed TBCs is discussed.

Analysis of coating structures and interfaces in solid oral dosage forms by three dimensional terahertz pulsed imaging.

PubMed

Zeitler, J Axel; Shen, Yaochun; Baker, Colin; Taday, Philip F; Pepper, Michael; Rades, Thomas

2007-02-01

Three dimensional terahertz pulsed imaging (TPI) was evaluated as a novel tool for the nondestructive characterization of different solid oral dosage forms. The time-domain reflection signal of coherent pulsed light in the far infrared was used to investigate film-coated tablets, sugar-coated tablets, multilayered controlled release tablets, and soft gelatin capsules. It is possible to determine the spatial and statistical distribution of coating thickness in single and multiple coated products using 3D TPI. The measurements are nondestructive even for layers buried underneath other coating structures. The internal structure of coating materials can be analyzed. As the terahertz signal penetrates up to 3 mm into the dosage form interfaces between layers in multilayered tablets can be investigated. In soft gelatin capsules it is possible to measure the thickness of the gelatin layer and to characterize the seal between the gelatin layers for quality control. TPI is a unique approach for the nondestructive characterization and quality control of solid dosage forms. The measurements are fast and fully automated with the potential for much wider application of the technique in the process analytical technology scheme. Copyright (c) 2006 Wiley-Liss, Inc.

Repair of a Mirror Coating on a Large Optic for High Laser Damage Applications using Ion Milling and Over-Coating Methods.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Field, Ella Suzanne; Bellum, John Curtis; Kletecka, Damon E.

When an optical coating is damaged, deposited incorrectly, or is otherwise unsuitable, the conventional method to restore the optic often entails repolishing the optic surface, which can incur a large cost and long lead time. We propose three alternative options to repolishing, including (i) burying the unsuitable coating under another optical coating, (ii) using ion milling to etch the unsuitable coating completely from the optic surface, and then recoating the optic, and (iii) using ion milling to etch through a number of unsuitable layers, leaving the rest of the coating intact, and then recoating the layers that were etched. Repairsmore » were made on test optics with dielectric mirror coatings according to the above three options. The mirror coatings to be repaired were quarter wave stacks of HfO 2 and SiO 2 layers for high reflection at 1054 nm at 45° incidence in P-polarization. One of the coating layers was purposely deposited incorrectly as Hf metal instead of HfO 2 to evaluate the ability of each repair method to restore the coating’s high laser-induced damage threshold (LIDT) of 64.0 J/cm 2. Finally, the repaired coating with the highest resistance to laser-induced damage was achieved using repair method (ii) with an LIDT of 49.0 – 61.0 J/cm 2.« less

Repair of a mirror coating on a large optic for high laser damage applications using ion milling and over-coating methods

DOE PAGES

Field, Ella S.; Bellum, John C.; Kletecka, Damon E.

2016-07-08

Here, when an optical coating is damaged, deposited incorrectly, or is otherwise unsuitable, the conventional method to restore the optic often entails repolishing the optic surface, which can incur a large cost and long lead time. We propose three alternative options to repolishing, including (i) burying the unsuitable coating under another optical coating, (ii) using ion milling to etch the unsuitable coating completely from the optic surface and then recoating the optic, and (iii) using ion milling to etch through a number of unsuitable layers, leaving the rest of the coating intact, and then recoating the layers that were etched.more » Repairs were made on test optics with dielectric mirror coatings according to the above three options. The mirror coatings to be repaired were quarter wave stacks of HfO 2 and SiO 2 layers for high reflection at 1054 nm at 45 deg incidence in P-polarization. One of the coating layers was purposely deposited incorrectly as Hf metal instead of HfO2 to evaluate the ability of each repair method to restore the coating’s high laser-induced damage threshold (LIDT) of 64.0 J/cm 2. The repaired coating with the highest resistance to laser-induced damage was achieved using repair method (ii) with an LIDT of 49.0 to 61.0 J/cm 2.« less

Repair of a Mirror Coating on a Large Optic for High Laser Damage Applications using Ion Milling and Over-Coating Methods.

DOE PAGES

Field, Ella Suzanne; Bellum, John Curtis; Kletecka, Damon E.

2016-06-01

When an optical coating is damaged, deposited incorrectly, or is otherwise unsuitable, the conventional method to restore the optic often entails repolishing the optic surface, which can incur a large cost and long lead time. We propose three alternative options to repolishing, including (i) burying the unsuitable coating under another optical coating, (ii) using ion milling to etch the unsuitable coating completely from the optic surface, and then recoating the optic, and (iii) using ion milling to etch through a number of unsuitable layers, leaving the rest of the coating intact, and then recoating the layers that were etched. Repairsmore » were made on test optics with dielectric mirror coatings according to the above three options. The mirror coatings to be repaired were quarter wave stacks of HfO 2 and SiO 2 layers for high reflection at 1054 nm at 45° incidence in P-polarization. One of the coating layers was purposely deposited incorrectly as Hf metal instead of HfO 2 to evaluate the ability of each repair method to restore the coating’s high laser-induced damage threshold (LIDT) of 64.0 J/cm 2. Finally, the repaired coating with the highest resistance to laser-induced damage was achieved using repair method (ii) with an LIDT of 49.0 – 61.0 J/cm 2.« less

Repair of a mirror coating on a large optic for high laser damage applications using ion milling and over-coating methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Field, Ella S.; Bellum, John C.; Kletecka, Damon E.

Here, when an optical coating is damaged, deposited incorrectly, or is otherwise unsuitable, the conventional method to restore the optic often entails repolishing the optic surface, which can incur a large cost and long lead time. We propose three alternative options to repolishing, including (i) burying the unsuitable coating under another optical coating, (ii) using ion milling to etch the unsuitable coating completely from the optic surface and then recoating the optic, and (iii) using ion milling to etch through a number of unsuitable layers, leaving the rest of the coating intact, and then recoating the layers that were etched.more » Repairs were made on test optics with dielectric mirror coatings according to the above three options. The mirror coatings to be repaired were quarter wave stacks of HfO 2 and SiO 2 layers for high reflection at 1054 nm at 45 deg incidence in P-polarization. One of the coating layers was purposely deposited incorrectly as Hf metal instead of HfO2 to evaluate the ability of each repair method to restore the coating’s high laser-induced damage threshold (LIDT) of 64.0 J/cm 2. The repaired coating with the highest resistance to laser-induced damage was achieved using repair method (ii) with an LIDT of 49.0 to 61.0 J/cm 2.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, E.

A new class of grout material based on molten wax offers a dramatic improvement in permeation grouting performance. This new material makes a perfect in situ containment of buried radioactive waste both feasible and cost effective. This paper describes various ways the material can be used to isolate buried waste in situ. Potential applications described in the paper include buried radioactive waste in deep trenches, deep shafts, Infiltration trenches, and large buried objects. Use of molten wax for retrieval of waste is also discussed. Wax can also be used for retrieval of air sensitive materials or drummed waste. This papermore » provides an analysis of the methods of application and the expected performance and cost of several potential projects. (authors)« less

Germination biology of Hibiscus tridactylites in Australia and the implications for weed management

PubMed Central

Chauhan, Bhagirath Singh

2016-01-01

Hibiscus tridactylites is a problematic broadleaf weed in many crops in Australia; however, very limited information is available on seed germination biology of Australian populations. Experiments were conducted to evaluate the effect of environmental factors on germination and emergence of H. tridactylites. Germination was stimulated by seed scarification, suggesting the inhibition of germination in this species is mainly due to the hard seed coat. Germination was not affected by light conditions, suggesting that seeds of this species are not photoblastic. Germination was higher at alternating day/night temperatures of 30/20 °C (74%) and 35/25 °C (69%) than at 25/15 °C (63%). Moderate salinity and water stress did not inhibit germination of H. tridactylites. Seedling emergence of H. tridactylites was highest (57%) for the seeds buried at a 2 cm depth in the soil; 18% of seedlings emerged from seeds buried at 8 cm but no seedlings emerged below this depth. Soil inversion by tillage to bury weed seeds below their maximum depth of emergence could serve an important tool for managing H. tridactylites. PMID:27174752

Germination biology of Hibiscus tridactylites in Australia and the implications for weed management

NASA Astrophysics Data System (ADS)

Chauhan, Bhagirath Singh

2016-05-01

Hibiscus tridactylites is a problematic broadleaf weed in many crops in Australia; however, very limited information is available on seed germination biology of Australian populations. Experiments were conducted to evaluate the effect of environmental factors on germination and emergence of H. tridactylites. Germination was stimulated by seed scarification, suggesting the inhibition of germination in this species is mainly due to the hard seed coat. Germination was not affected by light conditions, suggesting that seeds of this species are not photoblastic. Germination was higher at alternating day/night temperatures of 30/20 °C (74%) and 35/25 °C (69%) than at 25/15 °C (63%). Moderate salinity and water stress did not inhibit germination of H. tridactylites. Seedling emergence of H. tridactylites was highest (57%) for the seeds buried at a 2 cm depth in the soil; 18% of seedlings emerged from seeds buried at 8 cm but no seedlings emerged below this depth. Soil inversion by tillage to bury weed seeds below their maximum depth of emergence could serve an important tool for managing H. tridactylites.

System and Method for Fabricating Super Conducting Circuitry on Both Sides of an Ultra-Thin Layer

NASA Technical Reports Server (NTRS)

Brown, Ari D. (Inventor); Mikula, Vilem (Inventor)

2017-01-01

A method of fabricating circuitry in a wafer includes depositing a superconducting metal on a silicon on insulator wafer having a handle wafer, coating the wafer with a sacrificial layer and bonding the wafer to a thermally oxide silicon wafer with a first epoxy. The method includes flipping the wafer, thinning the flipped wafer by removing a handle wafer, etching a buried oxide layer, depositing a superconducting layer, bonding the wafer to a thermally oxidized silicon wafer having a handle wafer using an epoxy, flipping the wafer again, thinning the flipped wafer, etching a buried oxide layer from the wafer and etching the sacrificial layer from the wafer. The result is a wafer having superconductive circuitry on both sides of an ultra-thin silicon layer.

Identification of Buried Objects in GPR Using Amplitude Modulated Signals Extracted from Multiresolution Monogenic Signal Analysis

PubMed Central

Qiao, Lihong; Qin, Yao; Ren, Xiaozhen; Wang, Qifu

2015-01-01

It is necessary to detect the target reflections in ground penetrating radar (GPR) images, so that surface metal targets can be identified successfully. In order to accurately locate buried metal objects, a novel method called the Multiresolution Monogenic Signal Analysis (MMSA) system is applied in ground penetrating radar (GPR) images. This process includes four steps. First the image is decomposed by the MMSA to extract the amplitude component of the B-scan image. The amplitude component enhances the target reflection and suppresses the direct wave and reflective wave to a large extent. Then we use the region of interest extraction method to locate the genuine target reflections from spurious reflections by calculating the normalized variance of the amplitude component. To find the apexes of the targets, a Hough transform is used in the restricted area. Finally, we estimate the horizontal and vertical position of the target. In terms of buried object detection, the proposed system exhibits promising performance, as shown in the experimental results. PMID:26690146

Mid-Infrared Reflectance Imaging of Thermal-Barrier Coatings

NASA Technical Reports Server (NTRS)

Edlridge, Jeffrey I.; Martin, Richard E.

2009-01-01

An apparatus for mid-infrared reflectance imaging has been developed as means of inspecting for subsurface damage in thermal-barrier coatings (TBCs). The apparatus is designed, more specifically, for imaging the progression of buried delamination cracks in plasma-sprayed yttria-stabilized zirconia coatings on turbine-engine components. Progression of TBC delamination occurs by the formation of buried cracks that grow and then link together to produce eventual TBC spallation. The mid-infrared reflectance imaging system described here makes it possible to see delamination progression that is invisible to the unaided eye, and therefore give sufficiently advanced warning before delamination progression adversely affects engine performance and safety. The apparatus (see figure) includes a commercial mid-infrared camera that contains a liquid-nitrogen-cooled focal plane indium antimonide photodetector array, and imaging is restricted by a narrow bandpass centered at wavelength of 4 microns. This narrow wavelength range centered at 4 microns was chosen because (1) it enables avoidance of interfering absorptions by atmospheric OH and CO2 at 3 and 4.25 microns, respectively; and (2) the coating material exhibits maximum transparency in this wavelength range. Delamination contrast is produced in the midinfrared reflectance images because the introduction of cracks into the TBC creates an internal TBC/air-gap interface with a high diffuse reflectivity of 0.81, resulting in substantially higher reflectance of mid-infrared radiation in regions that contain buried delamination cracks. The camera is positioned a short distance (.12 cm) from the specimen. The mid-infrared illumination is generated by a 50-watt silicon carbide source positioned to the side of the mid-infrared camera, and the illumination is collimated and reflected onto the specimen by a 6.35-cm-diameter off-axis paraboloidal mirror. Because the collected images are of a steady-state reflected intensity (in contrast to the transient thermal response observed in infrared thermography), collection times can be lengthened to whatever extent needed to achieve desired signal-to-noise ratios. Each image is digitized, and the resulting data are processed in several steps to obtain a true mid-infrared reflectance image. The raw image includes thermal radiation emitted by the specimen in addition to the desired reflected radiation. The thermal-radiation contribution is eliminated by subtracting the image obtained with the illumination off from the image obtained with the illumination on. A flat-field correction is then made to remove the effects of non-uniformities in the illumination level and pixel-to-pixel variations in sensitivity. This correction is performed by normalizing to an image of a standard object that has a known reflectance at a wavelength of 4 microns. After correction, each pixel value is proportional to the reflectance (at a wavelength of 4-microns) at the corresponding location on the specimen. Mid-infrared reflectance imaging of specimens that were thermally cyc led for different numbers of cycles was performed and demonstrated t hat mid-infrared reflectance imaging was able to monitor the gradual delamination progression that occurs with continued thermal cycling . Reproducible values were obtained for the reflectance associated w ith an attached and fully delaminated TBC, so that intermediate refle ctance values could be interpreted to successfully predict the numbe r of thermal cycles to failure.

The acute and long-term neurotoxic effects of MDMA on marble burying behaviour in mice.

PubMed

Saadat, Kathryn S; Elliott, J Martin; Colado, M Isabel; Green, A Richard

2006-03-01

When mice are exposed to harmless objects such as marbles in their cage they bury them, a behaviour sometimes known as defensive burying. We investigated the effect of an acute dose of MDMA (èecstasy') and other psychoactive drugs on marble burying and also examined the effect of a prior neurotoxic dose of MDMA or p-chloroamphetamine (PCA) on burying. Acute administration of MDMA produced dose-dependent inhibition of marble burying (EC50: 7.6 micro mol/kg). Other drugs that enhance monoamine function also produced dose-dependent inhibition: methamphetamine PCA paroxetine MDMA GBR 12909 methylphenidate. None of these drugs altered locomotor activity at a dose that inhibited burying. A prior neurotoxic dose of MDMA, which decreased striatal dopamine content by 60%, but left striatal 5-HT content unaltered, did not alter spontaneous marble burying 18 or 40 days later. However, a neurotoxic dose of PCA which decreased striatal dopamine by 60% and striatal 5-HT by 70% attenuated marble burying 28 days later. Overall, these data suggest that MDMA, primarily by acutely increasing 5-HT function, acts like several anxiolytic drugs in this behavioural model. Long-term loss of cerebral 5-HT content also produced a similar effect. Since this change was observed only after 28 days, it is probably due to an adaptive response in the brain.

Dual-Use Applications of Infrared Sensitive Materials

DTIC Science & Technology

1993-06-01

only limit to MCT-based detectors’ market potential is in price. Specialty systems for subsurface imaging (such as buried storage tanks, toxic wastes...and assessment of automotive paint damaged by rust or stone impacts. Since automotive paint is a multi-layered coating, it lends itself to subsurface ... imaging , as well as aerospace aluminum and epoxy composites. Another family of non-destructive evaluation techniques which could use infrared detectors

Numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system

USGS Publications Warehouse

Cui, T.J.; Chew, W.C.; Aydiner, A.A.; Wright, D.L.; Smith, D.V.; Abraham, J.D.

2000-01-01

In this paper, two numerical models are presented to simulate an enhanced very early time electromagnetic (VETEM) prototype system, which is used for buried-object detection and environmental problems. Usually, the VETEM system contains a transmitting loop antenna and a receiving loop antenna, which run on a lossy ground to detect buried objects. In the first numerical model, the loop antennas are accurately analyzed using the Method of Moments (MoM) for wire antennas above or buried in lossy ground. Then, Conjugate Gradient (CG) methods, with the use of the fast Fourier transform (FFT) or MoM, are applied to investigate the scattering from buried objects. Reflected and scattered magnetic fields are evaluated at the receiving loop to calculate the output electric current. However, the working frequency for the VETEM system is usually low and, hence, two magnetic dipoles are used to replace the transmitter and receiver in the second numerical model. Comparing these two models, the second one is simple, but only valid for low frequency or small loops, while the first modeling is more general. In this paper, all computations are performed in the frequency domain, and the FFT is used to obtain the time-domain responses. Numerical examples show that simulation results from these two models fit very well when the frequency ranges from 10 kHz to 10 MHz, and both results are close to the measured data.

Three-dimensional imaging of buried objects in very lossy earth by inversion of VETEM data

USGS Publications Warehouse

Cui, T.J.; Aydiner, A.A.; Chew, W.C.; Wright, D.L.; Smith, D.V.

2003-01-01

The very early time electromagnetic system (VETEM) is an efficient tool for the detection of buried objects in very lossy earth, which allows a deeper penetration depth compared to the ground-penetrating radar. In this paper, the inversion of VETEM data is investigated using three-dimensional (3-D) inverse scattering techniques, where multiple frequencies are applied in the frequency range from 0-5 MHz. For small and moderately sized problems, the Born approximation and/or the Born iterative method have been used with the aid of the singular value decomposition and/or the conjugate gradient method in solving the linearized integral equations. For large-scale problems, a localized 3-D inversion method based on the Born approximation has been proposed for the inversion of VETEM data over a large measurement domain. Ways to process and to calibrate the experimental VETEM data are discussed to capture the real physics of buried objects. Reconstruction examples using synthesized VETEM data and real-world VETEM data are given to test the validity and efficiency of the proposed approach.

Development of dual sensor hand-held detector

NASA Astrophysics Data System (ADS)

Sezgin, Mehmet

2010-04-01

In this paper hand-held dual sensor detector development requirements are considered dedicated to buried object detection. Design characteristics of such a system are categorized and listed. Hardware and software structures, ergonomics, user interface, environmental and EMC/EMI tests to be applied and performance test issues are studied. Main properties of the developed system (SEZER) are presented, which contains Metal Detector (MD) and Ground Penetrating Radar (GPR). The realized system has ergonomic structure and can detect both metallic and non-metallic buried objects. Moreover classification of target is possible if it was defined to the signal processing software in learning phase.

Dye-sensitized photoelectrochemical water oxidation through a buried junction.

PubMed

Xu, Pengtao; Huang, Tian; Huang, Jianbin; Yan, Yun; Mallouk, Thomas E

2018-06-18

Water oxidation has long been a challenge in artificial photosynthetic devices that convert solar energy into fuels. Water-splitting dye-sensitized photoelectrochemical cells (WS-DSPECs) provide a modular approach for integrating light-harvesting molecules with water-oxidation catalysts on metal-oxide electrodes. Despite recent progress in improving the efficiency of these devices by introducing good molecular water-oxidation catalysts, WS-DSPECs have poor stability, owing to the oxidation of molecular components at very positive electrode potentials. Here we demonstrate that a solid-state dye-sensitized solar cell (ss-DSSC) can be used as a buried junction for stable photoelectrochemical water splitting. A thin protecting layer of TiO 2 grown by atomic layer deposition (ALD) stabilizes the operation of the photoanode in aqueous solution, although as a solar cell there is a performance loss due to increased series resistance after the coating. With an electrodeposited iridium oxide layer, a photocurrent density of 1.43 mA cm -2 was observed in 0.1 M pH 6.7 phosphate solution at 1.23 V versus reversible hydrogen electrode, with good stability over 1 h. We measured an incident photon-to-current efficiency of 22% at 540 nm and a Faradaic efficiency of 43% for oxygen evolution. While the potential profile of the catalyst layer suggested otherwise, we confirmed the formation of a buried junction in the as-prepared photoelectrode. The buried junction design of ss-DSSs adds to our understanding of semiconductor-electrocatalyst junction behaviors in the presence of a poor semiconducting material.

A comparison of iron oxide-rich joint coatings and rock chips as geochemical sampling media in exploration for disseminated gold deposits

USGS Publications Warehouse

Crone, W.; Larson, L.T.; Carpenter, R.H.; Chao, T.T.; Sanzolone, R.F.

1984-01-01

We evaluated the effectiveness of iron oxide-rich fracture coatings as a geochemical sampling medium for disseminated gold deposits, as compared with conventional lithogeochemical methods, for samples from the Pinson mine and Preble prospect in southeastern Humboldt County, Nevada. That disseminated gold mineralization is associated with Hg, As, and Sb is clearly demonstrated in these deposits for both fracture coatings and rock chip samples. However, the relationship is more pronounced for fracture coatings. Fracture coatings at Pinson contain an average of 3.61, 5.13, 14.37, and 3.42 times more Au, As, Sb and Hg, respectively, than adjacent rock samples. At Preble, fracture coatings contain 3.13, 9.72, 9.18, and 1.85 times more Au, As, Sb and Hg, respectively, than do adjacent rock samples. Geochemical anomalies determined from fracture coatings are thus typically more intense than those determined from rock samples for these elements. The sizes of anomalies indicated by fracture coatings are also somewhat larger, but this is less obvious. In both areas, Sb anomalies are more extensive in fracture coatings. At Preble, some Hg and Au anomalies are also more extensive in fracture coatings. In addition to halos formed by the Hg, As and Sb, high values for Au/Ag and Zn/(Fe + Mn) are closely associated with gold mineralization at the Pinson mine. The large enhancement in geochemical response afforded by fracture coatings indicates a definite potential in the search for buried disseminated gold deposits. ?? 1984.

Biodegradability of regenerated cellulose films coated with polyurethane/natural polymers interpenetrating polymer networks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, L.; Zhou, J.; Huang, J.

1999-11-01

Interpenetrating polymer network (IPN) coatings synthesized from castor-oil-based polyurethane (PU) with chitosan, nitrocellulose, or elaeostearin were coated on regenerated cellulose (RC) film for curing at 80--100 C for 2--5 min, providing biodegradable, water-resistant cellulose films coded, respectively, as RCCH, RCNC, and RCEs. The coated films were buried in natural soil for decaying and inoculated with a spore suspension of fungi on the agar medium, respectively, to test biodegradability. The viscosity-average molecular weight, M{sub {eta}}, and the weight of the degraded films decreased sharply with the progress of degradation. The degradation half-lifes, t{sub 1/2}, of the films in soil at 30more » C were found to be 19 days for RC, 25 days for RCNC, 32 days for RCCH, and 45 days for the RCEs films. Scanning electron microscopy (SEM) showed that the extent of decay followed in the order RC {gt} RCNC {gt} RCCH {gt} RCEs. SEM, infrared (IR), high-performance liquid chromatography (HPLC), and CO{sub 2} evolution results indicated that the microorganisms directly attacked the water-resistant coating layer and then penetrated into the cellulose to speedily metabolize, while accompanying with producing CO{sub 2}, H{sub 2}O, glucose cleaved from cellulose, and small molecules decomposed from the coatings.« less

Comprehensive Review and Case Study on the Management of Buried Penis Syndrome and Related Panniculectomy

PubMed Central

Burns, Hadley; Chowdhry, Saeed; Lee, Thomas; Schulz, Steven; Wilhelmi, Bradon J.

2018-01-01

Objective: This paper discusses the various surgical techniques and outcomes associated with management of buried penis syndrome. Methods: Presented is the case of a 49-year-old man with morbid obesity, leading to massive panniculus and buried penis. We review our technique for reconstruction of the buried penis and treatment of the overlying large panniculus. Literature search was conducted to review current techniques in correcting buried penis syndrome. Results: The patient underwent a successful panniculectomy with removal of all excess skin and tissue. Thoughtful planning and coordination between plastic surgery and urology were paramount to externalize the penis for an excellent functional and cosmetic result. Conclusions: Management of a buried, hidden penis is complex and difficult. Patients are often obese and have poor hygiene due to the inability to cleanse areas that are entrapped by excessive fat. Following removal of the overhanging panniculus, satisfactory reconstruction of a hidden penis is possible when proper care is taken to adhere the base of the penis to the pubis. Split-thickness skin grafts are often necessary but depend on the viability of the penile skin and whether it is restricting penile length. Complications with wound dehiscence and infection are not uncommon; however, patients generally recover well, are satisfied with results, and are reported to have fully regained urinary and sexual functions following surgical correction of the buried penis. PMID:29467914

Sensing a buried resonant object by single-channel time reversal.

PubMed

Waters, Zachary J; Dzikowicz, Benjamin R; Holt, R Glynn; Roy, Ronald A

2009-07-01

Scaled laboratory experiments are conducted to assess the efficacy of iterative, single-channel time reversal for enhancement of monostatic returns from resonant spheres in the free field and buried in a sediment phantom. Experiments are performed in a water tank using a broad-band piston transducer operating between 0.4 and 1.5 MHz and calibrated using free surface reflections. Solid and hollow metallic spheres, 6.35 mm in diameter, are buried in a consolidation of 128-microm-mean- diameter spherical glass beads. The procedure consists of exciting the target object with a broadband pulse, sampling the return using a finite time window, reversing the signal in time, and using this reversed signal as the source waveform for the next interrogation. Results indicate that the spectrum of the returns rapidly converges to the dominant mode in the backscattering response of the target. Signal-to-noise enhancement of the target echo is demonstrated for a target at several burial depths. Images generated by scanning the transducer over the location of multiple buried targets demonstrate the ability of the technique to distinguish between targets of differing type and to yield an enhancement of different modes within the response of a single target as a function of transducer position and processing bandwidth.

Buried mine detection using fractal geometry analysis to the LWIR successive line scan data image

NASA Astrophysics Data System (ADS)

Araki, Kan

2012-06-01

We have engaged in research on buried mine/IED detection by remote sensing method using LWIR camera. A IR image of a ground, containing buried objects can be assumed as a superimposed pattern including thermal scattering which may depend on the ground surface roughness, vegetation canopy, and effect of the sun light, and radiation due to various heat interaction caused by differences in specific heat, size, and buried depth of the objects and local temperature of their surrounding environment. In this cumbersome environment, we introduce fractal geometry for analyzing from an IR image. Clutter patterns due to these complex elements have oftentimes low ordered fractal dimension of Hausdorff Dimension. On the other hand, the target patterns have its tendency of obtaining higher ordered fractal dimension in terms of Information Dimension. Random Shuffle Surrogate method or Fourier Transform Surrogate method is used to evaluate fractional statistics by applying shuffle of time sequence data or phase of spectrum. Fractal interpolation to each line scan was also applied to improve the signal processing performance in order to evade zero division and enhance information of data. Some results of target extraction by using relationship between low and high ordered fractal dimension are to be presented.

Detection of buried magnetic objects by a SQUID gradiometer system

NASA Astrophysics Data System (ADS)

Meyer, Hans-Georg; Hartung, Konrad; Linzen, Sven; Schneider, Michael; Stolz, Ronny; Fried, Wolfgang; Hauspurg, Sebastian

2009-05-01

We present a magnetic detection system based on superconducting gradiometric sensors (SQUID gradiometers). The system provides a unique fast mapping of large areas with a high resolution of the magnetic field gradient as well as the local position. A main part of this work is the localization and classification of magnetic objects in the ground by automatic interpretation of geomagnetic field gradients, measured by the SQUID system. In accordance with specific features the field is decomposed into segments, which allow inferences to possible objects in the ground. The global consideration of object describing properties and their optimization using error minimization methods allows the reconstruction of superimposed features and detection of buried objects. The analysis system of measured geomagnetic fields works fully automatically. By a given surface of area-measured gradients the algorithm determines within numerical limits the absolute position of objects including depth with sub-pixel accuracy and allows an arbitrary position and attitude of sources. Several SQUID gradiometer data sets were used to show the applicability of the analysis algorithm.

In situ vitrification application to buried waste: Final report of intermediate field tests at Idaho National Engineering Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Callow, R.A.; Weidner, J.R.; Loehr, C.A.

This report describes two in situ vitrification field tests conducted on simulated buried waste pits during June and July 1990 at the Idaho National Engineering Laboratory. In situ vitrification, an emerging technology for in place conversion of contaminated soils into a durable glass and crystalline waste form, is being investigated as a potential remediation technology for buried waste. The overall objective of the two tests was to access the general suitability of the process to remediate waste structures representative of buried waste found at Idaho National Engineering Laboratory. In particular, these tests, as part of a treatability study, were designedmore » to provide essential information on the field performance of the process under conditions of significant combustible and metal wastes and to test a newly developed electrode feed technology. The tests were successfully completed, and the electrode feed technology successfully processed the high metal content waste. Test results indicate the process is a feasible technology for application to buried waste. 33 refs., 109 figs., 39 tabs.« less

Detection of Buried Objects by Means of a SAP Technique: Comparing MUSIC- and SVR-Based Approaches

NASA Astrophysics Data System (ADS)

Meschino, S.; Pajewski, L.; Pastorino, M.; Randazzo, A.; Schettini, G.

2012-04-01

This work is focused on the application of a Sub-Array Processing (SAP) technique to the detection of metallic cylindrical objects embedded in a dielectric half-space. The identification of buried cables, pipes, conduits, and other cylindrical utilities, is an important problem that has been extensively studied in the last years. Most commonly used approaches are based on the use of electromagnetic sensing: a set of antennas illuminates the ground and the collected echo is analyzed in order to extract information about the scenario and to localize the sought objects [1]. In a SAP approach, algorithms for the estimation of Directions of Arrival (DOAs) are employed [2]: they assume that the sources (in this paper, currents induced on buried targets) are in the far-field region of the receiving array, so that the received wavefront can be considered as planar, and the main angular direction of the field can be estimated. However, in electromagnetic sensing of buried objects, the scatterers are usually quite near to the antennas. Nevertheless, by dividing the whole receiving array in a suitable number of sub-arrays, and by finding a dominant DOA for each one, it is possible to localize objects that are in the far-field of the sub-array, although being in the near-field of the array. The DOAs found by the sub-arrays can be triangulated, obtaining a set of crossings with intersections condensed around object locations. In this work, the performances of two different DOA algorithms are compared. In particular, a MUltiple SIgnal Classification (MUSIC)-type method [3] and Support Vector Regression (SVR) based approach [4] are employed. The results of a Cylindrical-Wave Approach forward solver are used as input data of the detection procedure [5]. To process the crossing pattern, the region of interest is divided in small windows, and a Poisson model is adopted for the statistical distribution of intersections in the windows. Hypothesis testing procedures are used (imposing a suitable threshold from a desired false-alarm rate), to ascribe each window to the ground or to the sought objects. Numerical results are presented, for a test scenario with a circular-section cylinder in a dielectric half-space. Different values of the ground permittivity, target size, and its position with respect to the receiving array, are considered. Preliminary results on the application of MUSIC and SVR to multiple-object localization are reported. [1] H. Jol, Ground Penetrating Radar: Theory and Applications, Elsevier, Amsterdam, NL, 2009. [2] Gross F.B., Smart Antennas for Wireless Communications, McGraw-Hill, New York 2005. [3] S. Meschino, L. Pajewski, G. Schettini, "Use of a Sub-Array Statistical Approach for the Detection of a Buried Object", Near Surface Geophysics, vol. 8(5), pp. 365-375, 2010. [4] M. Pastorino, A. Randazzo, "A Smart Antenna System for Direction of Arrival Estimation based on a Support Vector Regression," IEEE Trans. Antennas Propagat., vol. 53(7), pp. 2161-2168, 2005. [5] M. Di Vico, F. Frezza, L. Pajewski, G. Schettini, "Scattering by a Finite Set of Perfectly Conducting Cylinders Buried in a Dielectric Half-Space: a Spectral-Domain Solution," IEEE Trans. Antennas Propagat., vol. 53(2), pp. 719-727, 2005.

Object Locating System

NASA Technical Reports Server (NTRS)

Arndt, G. Dickey (Inventor); Carl, James R. (Inventor)

2000-01-01

A portable system is provided that is operational for determining, with three dimensional resolution, the position of a buried object or approximately positioned object that may move in space or air or gas. The system has a plurality of receivers for detecting the signal front a target antenna and measuring the phase thereof with respect to a reference signal. The relative permittivity and conductivity of the medium in which the object is located is used along with the measured phase signal to determine a distance between the object and each of the plurality of receivers. Knowing these distances. an iteration technique is provided for solving equations simultaneously to provide position coordinates. The system may also be used for tracking movement of an object within close range of the system by sampling and recording subsequent position of the object. A dipole target antenna. when positioned adjacent to a buried object, may be energized using a separate transmitter which couples energy to the target antenna through the medium. The target antenna then preferably resonates at a different frequency, such as a second harmonic of the transmitter frequency.

Using Mechanical Energy as a Probe for the Detection and Imaging of Shallow Buried Inclusions in Dry Granular Beds

NASA Astrophysics Data System (ADS)

Sen, Surajit; Krishna Mohan, T. R.; Visco, Donald P.; Swaminathan, Saravanan; Sokolow, Adam; Avalos, Edgar; Nakagawa, Masami

Mechanical energy, such as sound waves and impulses, have been used to detect shallow buried objects for more than half a century. Yet, very little is understood about how mechanical energy propagates into one of the simplest kinds of soil, namely, a granular bed. Here we present an overview of the state of the art in our understanding of mechanical energy propagation in granular beds.

Measurements and modeling of acoustic scattering from partially and completely buried spherical shells

NASA Astrophysics Data System (ADS)

Tesei, A.; Maguer, A.; Fox, W. L. J.; Lim, R.; Schmidt, H.

2002-11-01

The use of low-frequency sonars (2-15 kHz) is explored to better exploit scattering features of buried targets that can contribute to their detection and classification. Compared to conventional mine countermeasure sonars, sound penetrates better into the sediment at these frequencies, and the excitation of structural waves in the targets is enhanced. The main contributions to target echo are the specular reflection, geometric diffraction effects, and the structural response, with the latter being particularly important for man-made elastic objects possessing particular symmetries such as bodies of revolution. The resonance response derives from elastic periodic phenomena such as surface circumferential waves revolving around the target. The GOATS'98 experiment, conducted jointly by SACLANTCEN and MIT off the island of Elba, involved controlled monostatic measurements of scattering by spherical shells which were partially and completely buried in sand, and suspended in the water column. The analysis mainly addresses a study of the effect of burial on the dynamics of backscattered elastic waves, which can be clearly identified in the target responses, and is based on the comparison of measurements with appropriate scattering models. Data interpretation results are in good agreement with theory. This positive result demonstrates the applicability of low-frequency methodologies based on resonance analysis to the classification of buried objects. copyright 2002 Acoustical Society of America.

Detection of buried objects by fusing dual-band infrared images

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, G.A.; Sengupta, S.K.; Sherwood, R.J.

1993-11-01

We have conducted experiments to demonstrate the enhanced detectability of buried land mines using sensor fusion techniques. Multiple sensors, including visible imagery, infrared imagery, and ground penetrating radar (GPR), have been used to acquire data on a number of buried mines and mine surrogates. Because the visible wavelength and GPR data are currently incomplete. This paper focuses on the fusion of two-band infrared images. We use feature-level fusion and supervised learning with the probabilistic neural network (PNN) to evaluate detection performance. The novelty of the work lies in the application of advanced target recognition algorithms, the fusion of dual-band infraredmore » images and evaluation of the techniques using two real data sets.« less

Managing previously disposed waste to today's standards

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1990-01-01

A Radioactive Waste Management Complex (RWMC) was established at the Idaho National Engineering Laboratory (INEL) in 1952 for controlled disposal of radioactive waste generated at the INEL. Between 1954 and 1970 waste characterized by long lived, alpha emitting radionuclides from the Rocky Flats Plant was also buried at this site. Migration of radionuclides and other hazardous substances from the buried Migration of radionuclides and other hazardous substances from the buried waste has recently been detected. A Buried Waste Program (BWP) was established to manage cleanup of the buried waste. This program has four objectives: (1) determine contaminant sources, (2) determinemore » extent of contamination, (3) mitigate migration, and (4) recommend an alternative for long term management of the waste. Activities designed to meet these objectives have been under way since the inception of the program. The regulatory environment governing these activities is evolving. Pursuant to permitting activities under the Resource Conservation and Recovery Act (RCRA), the Department of Energy (DOE) and the Environmental Protection Agency (EPA) entered into a Consent Order Compliance Agreement (COCA) for cleanup of past practice disposal units at the INEL. Subsequent to identification of the RWMC as a release site, cleanup activities proceeded under dual regulatory coverage of RCRA and the Atomic Energy Act. DOE, EPA, and the State of Idaho are negotiating a RCRA/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Interagency Agreement (IAG) for management of waste disposal sites at the INEL as a result of the November 1989 listing of the INEL on the National Priority List (NPL). Decision making for selection of cleanup technology will be conducted under the CERCLA process supplemented as required to meet the requirements of the National Environmental Policy Act (NEPA). 7 figs.« less

Buried Man-made Structure Imaging using 2-D Resistivity Inversion

NASA Astrophysics Data System (ADS)

Anderson Bery, Andy; Nordiana, M. M.; El Hidayah Ismail, Noer; Jinmin, M.; Nur Amalina, M. K. A.

2018-04-01

This study is carried out with the objective to determine the suitable resistivity inversion method for buried man-made structure (bunker). This study was carried out with two stages. The first stage is suitable array determination using 2-D computerized modeling method. One suitable array is used for the infield resistivity survey to determine the dimension and location of the target. The 2-D resistivity inversion results showed that robust inversion method is suitable to resolve the top and bottom part of the buried bunker as target. In addition, the dimension of the buried bunker is successfully determined with height of 7 m and length of 20 m. The location of this target is located at -10 m until 10 m of the infield resistivity survey line. The 2-D resistivity inversion results obtained in this study showed that the parameters selection is important in order to give the optimum results. These parameters are array type, survey geometry and inversion method used in data processing.

Fusion of Local Statistical Parameters for Buried Underwater Mine Detection in Sonar Imaging

NASA Astrophysics Data System (ADS)

Maussang, F.; Rombaut, M.; Chanussot, J.; Hétet, A.; Amate, M.

2008-12-01

Detection of buried underwater objects, and especially mines, is a current crucial strategic task. Images provided by sonar systems allowing to penetrate in the sea floor, such as the synthetic aperture sonars (SASs), are of great interest for the detection and classification of such objects. However, the signal-to-noise ratio is fairly low and advanced information processing is required for a correct and reliable detection of the echoes generated by the objects. The detection method proposed in this paper is based on a data-fusion architecture using the belief theory. The input data of this architecture are local statistical characteristics extracted from SAS data corresponding to the first-, second-, third-, and fourth-order statistical properties of the sonar images, respectively. The interest of these parameters is derived from a statistical model of the sonar data. Numerical criteria are also proposed to estimate the detection performances and to validate the method.

Genesis, evolution, and catastrophic burying of the Ryshkovo paleosol of the Mikulino Interglacial (MIS 5e)

NASA Astrophysics Data System (ADS)

Sycheva, S. A.; Sedov, S. N.; Bronnikova, M. A.; Targulian, V. O.; Solleiro-Rebolledo, E.

2017-09-01

The results of a hierarchical morphogenetic, physicochemical, and mineralogical study of the Ryshkovo full-profile texture-differentiated paleosol of the Mikulino Interglacial from the section at Aleksandrov quarry in Kursk oblast are discussed. The correlation analysis of the stratigraphy of this section with global geological records made it possible to determine the position of the Ryshkovo paleosol in the chronostratigraphic system of the Late Pleistocene and to attribute it to stage MIS 5e; the duration of pedogenesis for this paleosol was no more than 12-15 ka. The results of the study indicate that the Ryshkovo paleosol is close in its properties to the Holocene soddy-podzolic soils of the East European Plain. No direct evidences in favor of the former interpretation of this paleosol as a lessivated soil genetically close to Luvisols of nemoral broadleaved forest of Central Europe have been found. The difference between the paleosol of the Mikulino Interglacial and the modern soddy-podzolic soils is mainly related to the distribution of clay coatings. In the upper part of the illuvial horizon of Mikulino paleosol, clay coatings are few in number, and typical tongues of podzolized (albic) material are absent in the profile. At the same time, silty coatings (skeletans) are abundant even in the lower part of the illuvial horizon. In general, the Mikulino paleosol is characterized by a smaller diversity of clay pedofeatures. These differences might be related to less contrasting fluctuations of the environmental conditions in the second half of the Mikulino Interglacial, to the periodical renewal of the eluvial part of Mikulino paleosol by erosional and accumulative processes, and to the absence of anthropogenic impacts on the soil during the Mikulino Interglacial. The burying of the Ryshkovo paleosol took place due to the intense development of erosional processes induced by the contrasting climatic events at the end of the interglacial period accompanied by catastrophic forest fires and sharp cooling of the climate upon the transition to the Valdai glaciation.

Ferromagnetic Objects Magnetovision Detection System.

PubMed

Nowicki, Michał; Szewczyk, Roman

2013-12-02

This paper presents the application of a weak magnetic fields magnetovision scanning system for detection of dangerous ferromagnetic objects. A measurement system was developed and built to study the magnetic field vector distributions. The measurements of the Earth's field distortions caused by various ferromagnetic objects were carried out. The ability for passive detection of hidden or buried dangerous objects and the determination of their location was demonstrated.

Microscale Characterization and Trace Element Distribution in Bacteriogenic Ferromanganese Coatings on Sand Grains from an Intertidal Zone of the East China Sea

PubMed Central

Yuan, Linxi; Sun, Liguang; Fortin, Danielle; Wang, Yuhong; Yin, Xuebin

2015-01-01

An ancient wood layer dated at about 5600 yr BP by accelerator mass spectrometry (AMS) 14C was discovered in an intertidal zone of the East China Sea. Extensive and horizontally stratified sediments with black color on the top and yellowish-red at the bottom, and some nodule-cemented concretions with brown surface and black inclusions occurred in this intertidal zone. Microscale analysis methods were employed to study the microscale characterization and trace element distribution in the stratified sediments and concretions. Light microscopy, scanning electron microscopy (SEM) and backscattered electron imaging (BSE) revealed the presence of different coatings on the sand grains. The main mineral compositions of the coatings were ferrihydrite and goethite in the yellowish-red parts, and birnessite in the black parts using X-ray powder diffraction (XRD). SEM observations showed that bacteriogenic products and bacterial remnants extensively occurred in the coatings, indicating that bacteria likely played an important role in the formation of ferromanganese coatings. Post-Archean Australian Shale (PAAS)-normalized middle rare earth element (MREE) enrichment patterns of the coatings indicated that they were caused by two sub-sequential processes: (1) preferentially release of Fe-Mn from the beach rocks by fermentation of ancient woods and colloidal flocculation in the mixing water zone and (2) preferential adsorption of MREE by Fe-Mn oxyhydroxides from the seawater. The chemical results indicated that the coatings were enriched with Sc, V, Cr, Co, Ni, Cu, Zn, Ba, especially with respect to Co, Ni. The findings of the present study provide an insight in the microscale features of ferromanganese coatings and the Fe-Mn biogeochemical cycling during the degradation of buried organic matter in intertidal zones or shallow coasts. PMID:25786213

Back to basics: A methodological perspective on marble-burying behavior as a screening test for psychiatric illness.

PubMed

de Brouwer, Geoffrey; Wolmarans, De Wet

2018-04-22

Animal models of human psychiatric illness are valuable frameworks to investigate the etiology and neurobiology underlying the human conditions. Accurate behavioral measures that can be used to characterize animal behavior, thereby contributing to a model's validity, are crucial. One such measure, i.e. the rodent marble-burying test (MBT), is often applied as a measure of anxiety- and compulsive-like behaviors. However, the test is characterized by noteworthy between-laboratory methodological differences and demonstrates positive treatment responses to an array of pharmacotherapies that are often of little translational value. Therefore, using a naturalistic animal model of obsessive-compulsive disorder, i.e. the deer mouse (Peromyscus maniculatus bairdii), the current investigation attempted to illuminate the discrepancies reported in literature by means of a methodological approach to the MBT. Five key aspects of the test that vary between laboratories, viz. observer/scoring, burying substrate, optional avoidance, the use of repeated testing, and determinations of locomotor activity, have been investigated. Following repeated MB tests in four different burying substrates and in two zone configurations, we have demonstrated that 1) observer bias may contribute to the significant differences in findings reported, 2) MB seems to be a natural exploratory response to a novel environment, rather than being triggered by aberrant cognition, 3) burying substrates with a small particle size and higher density deliver the most accurate results with respect to the burying phenotype, and 4) to exclude the influence of normal exploratory behavior on the number of marbles being covered, assessments of marble-burying should be based on pre-occupation with the objects itself. Copyright © 2018 Elsevier B.V. All rights reserved.

Frequency-domain preprocessing and directional correlation-based feature extraction for classification of the buried objects using GPR B-scan data

NASA Astrophysics Data System (ADS)

Bahadirlar, Yildirim; Kaplan, Gulay B.

2004-09-01

A new preprocessing and feature extracting approach for classification of non-metallic buried objects are aimed using GPR B-scan data. A frequency-domain adaptive filter without a reference channel effectively removes the background signal resulting mostly from the discontinuity on the air-to-ground path of the electromagnetic waves. The filter only needs average of the first five A-scans as the reference signal for this elimination, and also serves for masking of the B-scan in the frequency-domain. A preprocessed GPR data with significantly suppressed clutter is then obtained by precisely positioning the Hanning window in the frequency-domain. A directional correlation function defined over a B-scan frame gives distinctive curves of buried objects. The main axis of directional correlation, on which the pivotal correlating pixels and short lines of pixels being correlated are considered, makes an angle to the scanning direction of the B-scan. This form of correlation is applied to the frame from the left-hand and the right-hand side and two over-plotted curves are obtained. Nine measures as features emphasizing directional signatures are extracted from these curves. Nine-element feature vectors are applied to the two-layer Artificial Neural Network and preliminary results over test set are promising to continue to comprehensive training and testing processes.

Standardized Analysis for UXO Demonstration Sites

DTIC Science & Technology

2008-04-01

is a time-domain electromagnetic instrument designed to detect shallow ferrous and nonferrous metallic objects. The applicability of the EM61 for UXO...or spots show EMI field anomalies caused by buried metal objects, both UXO and clutter. Anomaly maps for APG are shown in Figure 5. The Blind Grid

Very-high-resolution seismic and magnetic investigations of a chemical munition dumpsite in the Baltic Sea

NASA Astrophysics Data System (ADS)

Missiaen, Tine; Feller, Pascal

2008-09-01

Very-high-resolution (VHR) seismic and magnetic investigations were carried out over a chemical munition dumpsite in the Bornholm Basin, south-western Baltic Sea. The main goal of the investigations was to image the shallow internal structure of the dumpsite and to map the lateral and vertical distribution of the dumped war material. The shallow geology was imaged in great detail on the seismic data. Seven seismic-stratigraphic units were identified, related to different stages in the Holocene and late-glacial history. A large number of diapir-like features were observed that most likely represent fluid expulsion phenomena. Four shipwrecks were identified in the dumpsite area. The wrecks have partly sunk into the soft upper sediments, their height above the sea floor reaching no more than 2 m. Seismic and magnetic data indicate the presence of a large number of buried objects. In most cases there is a good correlation between the seismic and magnetic data sets. The objects are generally buried no deeper than 1 to 2 m. Their size varies between 1.5 and 5 m, occasionally up to 10 m. Shallow pits in the sea bed are likely due to the impact of dumping. The data confirm the wide variety of dumped war material ranging from bombs and shells to encasements and containers. The distribution of the buried objects seems rather heterogeneous, with locally high object concentrations surrounded by areas of lower object density. The results of this case study demonstrate the benefit of complementary, concurrent geophysical investigations for munition dumpsite research. Finally this will yield a better assessment of the current status of the dumpsite and the possible ecological risks related to the dumped war material.

47 CFR 15.503 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the images of buried objects or determining the physical properties within the ground. The energy from... dense enough to absorb the transmitted signal. (j) Surveillance system. A field disturbance sensor used...

47 CFR 15.503 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the images of buried objects or determining the physical properties within the ground. The energy from... dense enough to absorb the transmitted signal. (j) Surveillance system. A field disturbance sensor used...

47 CFR 15.503 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... the images of buried objects or determining the physical properties within the ground. The energy from... dense enough to absorb the transmitted signal. (j) Surveillance system. A field disturbance sensor used...

47 CFR 15.503 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the images of buried objects or determining the physical properties within the ground. The energy from... dense enough to absorb the transmitted signal. (j) Surveillance system. A field disturbance sensor used...

47 CFR 15.503 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the images of buried objects or determining the physical properties within the ground. The energy from... dense enough to absorb the transmitted signal. (j) Surveillance system. A field disturbance sensor used...

The Study of Indicatrices of Space Object Coatings in a Controlled Laboratory Environment

NASA Astrophysics Data System (ADS)

Koshkin, N.; Burlak, N.; Petrov, M.; Strakhova, S.

The indicatrices of light scattering by radiation balance coatings used on space objects (SO) were determined in the laboratory experiment in a controlled condition. The laboratory device for the physical simulation of photometric observations of space objects in orbit, which was used in this case to study optical properties of coating samples, is described. The features of light reflection off plane coating samples, including multi-layer insulation (MLI) blankets, metal surfaces coated with several layers of enamel EP-140, special polyacrylate enamel AK-512 and matte finish Tp-CO-2, were determined. The indicated coatings are compound reflectors which exhibit both diffuse and specular reflections. The data obtained are to be used in the development of computer optical-geometric models of space objects or their fragments (space debris) to interpret the photometry results for real space objects.

The Mars Express - NASA Project at JPL

NASA Technical Reports Server (NTRS)

Thompson, Thomas W.; Horttor, Richard L.; Acton, C. H., Jr.; Zamani, P.; Johnson, W. T. K.; Plaut, J. J.; Holmes, D. P.; No, S.; Asmar, S. W.; Goltz, G.

2006-01-01

This viewgraph presentation gives a general overview of the Mars Express NASA Project at JPL. The contents include: 1) Mars Express/NASA Project Overview; 2) Experiment-Investigator Matrix; 3) Mars Express Support of NASA's Mars Exploration Objectives; 4) U.S./NASA Support of Mars Express; 5) Mars Express Schedule (2003-2007); 6) Mars Express Data Rates; 7) MARSIS Overview Results; 8) MARSIS with Antennas Deployed; 9) MARSIS Science Objectives; 10) Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) Experiment Overview; 11) Mars Express Orbit Evolution; 12) MARSIS Science - Subsurface Sounding; 13) MARSIS-North Polar Ice Cap; 14) MARSIS Data-Buried Basin; 15) MARSIS over a Crater Basin; 16) MARSIS-Buried Basin; 17) Ionogram - Orbit 2032 (example from Science paper); 18) Ionogram-Orbit 2018 (example from Science paper); and 19) Recent MARSIS Results ESA Press Releases.

Dependence of LTX plasma performance on surface conditions as determined by in situ analysis of plasma facing components

NASA Astrophysics Data System (ADS)

Lucia, M.; Kaita, R.; Majeski, R.; Bedoya, F.; Allain, J. P.; Abrams, T.; Bell, R. E.; Boyle, D. P.; Jaworski, M. A.; Schmitt, J. C.

2015-08-01

The Materials Analysis and Particle Probe (MAPP) diagnostic has been implemented on the Lithium Tokamak Experiment (LTX) at PPPL, providing the first in situ X-ray photoelectron spectroscopy (XPS) surface characterization of tokamak plasma facing components (PFCs). MAPP samples were exposed to argon glow discharge conditioning (GDC), lithium evaporations, and hydrogen tokamak discharges inside LTX. Samples were analyzed with XPS, and alterations to surface conditions were correlated against observed LTX plasma performance changes. Argon GDC caused the accumulation of nm-scale metal oxide layers on the PFC surface, which appeared to bury surface carbon and oxygen contamination and thus improve plasma performance. Lithium evaporation led to the rapid formation of a lithium oxide (Li2O) surface; plasma performance was strongly improved for sufficiently thick evaporative coatings. Results indicate that a 5 h argon GDC or a 50 nm evaporative lithium coating will both significantly improve LTX plasma performance.

Hex Chrome Free Coatings for Electronics Overview

NASA Technical Reports Server (NTRS)

Kessel, Kurt

2013-01-01

The overall objective of the Hex Chrome Free Coatings for Electronics project is to evaluate and test pretreatment coating systems not containing hexavalent chrome in avionics and electronics housing applications. This objective will be accomplished by testing strong performing coating systems from prior NASA and DoD testing or new coating systems as determined by the stakeholders.

Buried Object Classification using a Sediment Volume Imaging SAS and Electromagnetic Gradiometer

DTIC Science & Technology

2006-09-01

field data with simulated RTG data using AST’s in-house magnetic modeling tool EMAGINE . Given a set of input dipole moments, or pa- rameters to...approximate a moment by assuming the object is a prolate ellipsoid shell, EMAGINE uses Green’s func- tion formulations to generate three-component

The Instructional Quality Inventory. I. Introduction and Overview

DTIC Science & Technology

1978-11-01

level objectives, "hands-on" performance tests are usually most appropriate. T IS PAQ IS BEST QUA After a test item is consistent with its objective, the...idea. When the statement is separated, the key points stand out, and are not buried in the presentation. There are several ways to accomplish this goal

Simple Anchoring of the Penopubic Skin to the Prepubic Deep Fascia in Surgical Correction of Buried Penis

PubMed Central

Jung, Eun-hong; Jang, Seok-heun; Lee, Jae-won

2011-01-01

Purpose The aim of this study was to categorize concealed penis and buried penis by preoperative physical examination including the manual prepubic compression test and to describe a simple surgical technique to correct buried penis that was based on surgical experience and comprehension of the anatomical components. Materials and Methods From March 2007 to November 2010, 17 patients were diagnosed with buried penis after differentiation of this condition from concealed penis. The described surgical technique consisted of a minimal incision and simple fixation of the penile shaft skin and superficial fascia to the prepubic deep fascia, without degloving the penile skin. Results The mean age of the patients was 10.2 years, ranging from 8 years to 15 years. The median follow-up was 19 months (range, 5 to 49 months). The mean penile lengths were 1.8 cm (range, 1.1 to 2.5 cm) preoperatively and 4.5 cm (range, 3.3 to 5.8 cm) postoperatively. The median difference between preoperative and postoperative penile lengths was 2.7 cm (range, 2.1 to 3.9 cm). There were no serious intra- or postoperative complications. Conclusions With the simple anchoring of the penopubic skin to the prepubic deep fascia, we obtained successful subjective and objective outcomes without complications. We suggest that this is a promising surgical method for selected patients with buried penis. PMID:22195270

Archaeology and public perception of a trans-scientific problem; disposal of toxic wastes in the unsaturated zone

USGS Publications Warehouse

Winograd, Isaac Judah

1986-01-01

Predicting the effects of toxic-waste disposal on the environment over periods of millenia to hundreds of millenia is a transscientific problem; that is, one not fully addressed by quantitative scientific and engineering endeavors. Archaeology is a pertinent adjunct to such predictions in several ways. First, and foremost, archaeological records demonstrate that delicate, as well as durable, objects buried in thick unsaturated zones of arid and semiarid environments may survive intact for millenia to tens of millenia. This successful preservation of Late Paleolithic to Iron Age artifacts provides independent support for the tentative favorable conclusions of earth scientists regarding the general utility of thick unsaturated zones for toxic-waste isolation. By analogy with the archaeological record, solidified toxic wastes of low solubility that are buried in arid unsaturated zones should remain isolated from the environment indefinitely; modern man presumably should be able to improve upon the techniques used by his ancestors to isolate and preserve their sacred and utilitarian objects. Second, archaeological evidence pertinent to the fate of objects buried in unsaturated zones-although qualitative in nature and subject to the limitations of arguments by analogy-is meaningful to the public and to the courts who, with some scientists and engineers, are reluctant to rely exclusively on computer-generated predictions of the effects of buried toxic wastes on the environment. Third, the archaeological record issues a warning that our descendants may intrude into our waste disposal sites and that we must therefore take special measures to minimize such entry and, if it occurs, to warn of the dangers by a variety of symbols. And fourth, archaeology provides a record of durable natural and manmade materials that may prove to be suitable for encapsulation of our wastes and from which we can construct warning markers that will last for millenia. For these four reasons, archaeologists must join with earth scientists, and other scientists and engineers, in addressing the likely fate of solidfied toxic wastes buried in the thick (200-600 m) unsaturated zones of arid and semiarid regions. Indeed, the input of archaeology might be crucial to public acceptance of even the most carefully chosen and technically sound waste repository.

Method of coating the interior surface of hollow objects with a diffusion coating

DOEpatents

Knowles, Shawn D.; Senor, David J.; Forbes, Steven V.; Johnson, Roger N.; Hollenberg, Glenn W.

2005-03-15

A method for forming a diffusion coating on the interior of surface of a hollow object wherein a filament, extending through a hollow object and adjacent to the interior surface of the object, is provided, with a coating material, in a vacuum. An electrical current is then applied to the filament to resistively heat the filament to a temperature sufficient to transfer the coating material from the filament to the interior surface of the object. The filament is electrically isolated from the object while the filament is being resistively heated. Preferably, the filament is provided as a tungsten filament or molybdenum filament. Preferably, the coating materials are selected from the group consisting of Ag, Al, As, Au, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Dy, Er, Eu, Fe, Ga, Ge, Hg, In, K, Li, Mg, Mn, Na, Ni P, Pb, Pd, Pr, S, Sb, Sc, Se, Si, Sn, Sr, Te, Tl, Y, Yb, Zn, and combinations thereof. The invention additionally allows for the formation of nitrides, hydrides, or carbides of all the possible coating materials, where such compounds exist, by providing a partial pressure of nitrogen, hydrogen, hydrocarbons, or combination thereof, within the vacuum.

The Spirit Rover's Athena science investigation at Gusev Crater, Mars

NASA Technical Reports Server (NTRS)

Squyres, S. W.; Arvidson, R. E.; Bell, J. F., III; Brueckner, J.; Cabrol, N. A.; Calvin, W.; Carr, M. H.; Christensen, P. R.; Clark, B. C.; Crumpler, L.;

The Spirit Rover's Athena science investigation at Gusev crater, Mars

USGS Publications Warehouse

Squyres, S. W.; Arvidson, R. E.; Bell, J.F.; Brückner, J.; Cabrol, N.A.; Calvin, W.; Carr, M.H.; Christensen, P.R.; Clark, B. C.; Crumpler, L.; Des Marais, D.J.; D'Uston, C.; Economou, T.; Farmer, J.; Farrand, W.; Folkner, W.; Golombek, M.; Gorevan, S.; Grant, J. A.; Greeley, R.; Grotzinger, J.; Haskin, L.; Herkenhoff, K. E.; Hviid, S.; Johnson, J.; Klingelhofer, G.; Knoll, A.; Landis, G.; Lemmon, M.; Li, R.; Madsen, M.B.; Malin, M.C.; McLennan, S.M.; McSween, H.Y.; Ming, D. W.; Moersch, J.; Morris, R.V.; Parker, T.; Rice, J. W.; Richter, L.; Rieder, R.; Sims, M.; Smith, M.; Smith, P.; Soderblom, L.A.; Sullivan, R.; Wanke, H.; Wdowiak, T.; Wolff, M.; Yen, A.

2004-01-01

The Mars Exploration Rover Spirit and its Athena science payload have been used to investigate a landing site in Gusev crater. Gusev is hypothesized to be the site of a former take, but no clear evidence for lacustrine sedimentation has been found to date. Instead, the dominant lithology is basalt, and the dominant geologic processes are impact events and eolian transport. Many rocks exhibit coatings and other characteristics that may be evidence for minor aqueous alteration. Any lacustrine sediments that may exist at this location within Gusev apparently have been buried by lavas that have undergone subsequent impact disruption.

Determination of conformation and orientation of immobilized peptides and proteins at buried interfaces

NASA Astrophysics Data System (ADS)

Shen, Lei; Ulrich, Nathan W.; Mello, Charlene M.; Chen, Zhan

2015-01-01

Surface immobilized peptides/proteins have important applications such as antimicrobial coating and biosensing. We report a study of such peptides/proteins using sum frequency generation vibrational spectroscopy and ATR-FTIR. Immobilization on surfaces via physical adsorption and chemical coupling revealed that structures of chemically immobilized peptides are determined by immobilization sites, chemical environments, and substrate surfaces. In addition, controlling enzyme orientation by engineering the surface immobilization site demonstrated that structures can be well-correlated to measured chemical activity. This research facilitates the development of immobilized peptides/proteins with improved activities by optimizing their surface orientation and structure.

METHOD FOR TESTING COATINGS

DOEpatents

Johns, I.B.; Newton, A.S.

1958-09-01

A method is described for detecting pin hole imperfections in coatings on uranium-metal objects. Such coated objects are contacted with a heated atmosphere of gaseous hydrogen and imperfections present in the coatings will allow the uranlum to react with the hydrogen to form uranium hydride. Since uranium hydride is less dense than uranium metal it will swell, causing enlargement of the coating defeot and rendering it visible.

STRIPPING PROCESS FOR PLUTONIUM

DOEpatents

Kolodney, M.

1959-10-01

A method for removing silver, nickel, cadmium, zinc, and indium coatings from plutonium objects while simultaneously rendering the plutonium object passive is described. The coated plutonium object is immersed as the anode in an electrolyte in which the plutonium is passive and the coating metal is not passive, using as a cathode a metal which does not dissolve rapidly in the electrolyte. and passing an electrical current through the electrolyte until the coating metal is removed from the plutonium body.

Radiation and Electromagnetic Induction Data Fusion for Detection of Buried Radioactive Metal Waste - 12282

DOE Office of Scientific and Technical Information (OSTI.GOV)

Long, Zhiling; Wei, Wei; Turlapaty, Anish

2012-07-01

At the United States Army's test sites, fired penetrators made of Depleted Uranium (DU) have been buried under ground and become hazardous waste. Previously, we developed techniques for detecting buried radioactive targets. We also developed approaches for locating buried paramagnetic metal objects by utilizing the electromagnetic induction (EMI) sensor data. In this paper, we apply data fusion techniques to combine results from both the radiation detection and the EMI detection, so that we can further distinguish among DU penetrators, DU oxide, and non- DU metal debris. We develop a two-step fusion approach for the task, and test it with surveymore » data collected on simulation targets. In this work, we explored radiation and EMI data fusion for detecting DU, oxides, and non-DU metals. We developed a two-step fusion approach based on majority voting and a set of decision rules. With this approach, we fuse results from radiation detection based on the RX algorithm and EMI detection based on a 3-step analysis. Our fusion approach has been tested successfully with data collected on simulation targets. In the future, we will need to further verify the effectiveness of this fusion approach with field data. (authors)« less

Sensing resonant objects in the presence of noise and clutter using iterative, single-channel acoustic time reversal

NASA Astrophysics Data System (ADS)

Waters, Zachary John

The presence of noise and coherent returns from clutter often confounds efforts to acoustically detect and identify target objects buried in inhomogeneous media. Using iterative time reversal with a single channel transducer, returns from resonant targets are enhanced, yielding convergence to a narrowband waveform characteristic of the dominant mode in a target's elastic scattering response. The procedure consists of exciting the target with a broadband acoustic pulse, sampling the return using a finite time window, reversing the signal in time, and using this reversed signal as the source waveform for the next interrogation. Scaled laboratory experiments (0.4-2 MHz) are performed employing a piston transducer and spherical targets suspended in the free field and buried in a sediment phantom. In conjunction with numerical simulations, these experiments provide an inexpensive and highly controlled means with which to examine the efficacy of the technique. Signal-to-noise enhancement of target echoes is demonstrated. The methodology reported provides a means to extract both time and frequency information for surface waves that propagate on an elastic target. Methods developed in the laboratory are then applied in medium scale (20-200 kHz) pond experiments for the detection of a steel shell buried in sandy sediment.

Analysis of Nb 3Sn surface layers for superconducting radio frequency cavity applications

DOE PAGES

Becker, Chaoyue; Posen, Sam; Groll, Nickolas; ...

2015-02-23

Here, we present an analysis of Nb 3Sn surface layers grown on a bulk Nb coupon prepared at the same time and by the same vapor diffusion process used to make Nb 3Sn coatings on 1.3 GHz Nb cavities. Tunneling spectroscopy reveal a well developed, homogeneous superconducting density of states at the surface with a gap value distribution centered around 2.7 ± 0.4 meV and superconducting critical temperature's (T c) up to 16.3K. Transmission electron microscopy (TEM) performed on cross sections of the sample's surface shows a ~ 2 microns thick Nb 3Sn surface layer. The elemental composition map exhibitsmore » a Nb:Sn ratio of 3:1 with buried substoichiometric regions with a ratio of 5:1. Synchrotron diffraction experiments indicate a polycrystalline Nb 3Sn film and confirm the presence of Nb rich regions that occupies about a third of the coating volume. These low T c regions could play an important role in the dissipation mechanisms occurring during RF tests of Nb 3Sn -coated Nb cavities and open the way for further improving a very promising alternative to pure Nb cavities for particle accelerators.« less

Sensor feature fusion for detecting buried objects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, G.A.; Sengupta, S.K.; Sherwood, R.J.

1993-04-01

Given multiple registered images of the earth`s surface from dual-band sensors, our system fuses information from the sensors to reduce the effects of clutter and improve the ability to detect buried or surface target sites. The sensor suite currently includes two sensors (5 micron and 10 micron wavelengths) and one ground penetrating radar (GPR) of the wide-band pulsed synthetic aperture type. We use a supervised teaming pattern recognition approach to detect metal and plastic land mines buried in soil. The overall process consists of four main parts: Preprocessing, feature extraction, feature selection, and classification. These parts are used in amore » two step process to classify a subimage. Thee first step, referred to as feature selection, determines the features of sub-images which result in the greatest separability among the classes. The second step, image labeling, uses the selected features and the decisions from a pattern classifier to label the regions in the image which are likely to correspond to buried mines. We extract features from the images, and use feature selection algorithms to select only the most important features according to their contribution to correct detections. This allows us to save computational complexity and determine which of the sensors add value to the detection system. The most important features from the various sensors are fused using supervised teaming pattern classifiers (including neural networks). We present results of experiments to detect buried land mines from real data, and evaluate the usefulness of fusing feature information from multiple sensor types, including dual-band infrared and ground penetrating radar. The novelty of the work lies mostly in the combination of the algorithms and their application to the very important and currently unsolved operational problem of detecting buried land mines from an airborne standoff platform.« less

LLNL electro-optical mine detection program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, C.; Aimonetti, W.; Barth, M.

1994-09-30

Under funding from the Advanced Research Projects Agency (ARPA) and the US Marine Corps (USMC), Lawrence Livermore National Laboratory (LLNL) has directed a program aimed at improving detection capabilities against buried mines and munitions. The program has provided a national test facility for buried mines in arid environments, compiled and distributed an extensive data base of infrared (IR), ground penetrating radar (GPR), and other measurements made at that site, served as a host for other organizations wishing to make measurements, made considerable progress in the use of ground penetrating radar for mine detection, and worked on the difficult problem ofmore » sensor fusion as applied to buried mine detection. While the majority of our effort has been concentrated on the buried mine problem, LLNL has worked with the U.S.M.C. on surface mine problems as well, providing data and analysis to support the COBRA (Coastal Battlefield Reconnaissance and Analysis) program. The original aim of the experimental aspect of the program was the utilization of multiband infrared approaches for the detection of buried mines. Later the work was extended to a multisensor investigation, including sensors other than infrared imagers. After an early series of measurements, it was determined that further progress would require a larger test facility in a natural environment, so the Buried Object Test Facility (BOTF) was constructed at the Nevada Test Site. After extensive testing, with sensors spanning the electromagnetic spectrum from the near ultraviolet to radio frequencies, possible paths for improvement were: improved spatial resolution providing better ground texture discrimination; analysis which involves more complicated spatial queueing and filtering; additional IR bands using imaging spectroscopy; the use of additional sensors other than IR and the use of data fusion techniques with multi-sensor data; and utilizing time dependent observables like temperature.« less

Hexavalent Chrome Free Coatings for Electronics Applications: Joint Test Report

NASA Technical Reports Server (NTRS)

Rothgeb, Matt; Kessel, Kurt

2013-01-01

The overall objective of the Hexavalent Chrome Free Coatings for Electronics Applications project is to evaluate and test pretreatments not containing hexavalent chrome in avionics and electronics housing applications. This objective will be accomplished by testing strong performing coating systems from prior NASA and DoD testing or new coating systems as determined by the stakeholders.

Optical Diagnostics for High-Temperature Thermal Barrier Coatings

NASA Technical Reports Server (NTRS)

Eldridge, Jeffrey I.

2009-01-01

Thermal barrier coatings (TBCs) are typically composed of translucent ceramic oxides that provide thermal protection for metallic components exposed to high-temperature environments, such as in jet turbine engines. Taking advantage of the translucent nature of TBCs, optical diagnostics have been developed that can provide an informed assessment of TBC health that will allow mitigating action to be taken before TBC degradation threatens performance or safety. In particular, rare-earth-doped luminescent sublayers have been integrated into the TBC structure to produce luminescence that monitors TBC erosion, delamination, and temperature gradients. Erosion monitoring of TBC-coated specimens is demonstrated by utilizing visible luminescence that is excited from a sublayer that is exposed by erosion. TBC delamination monitoring is achieved in TBCs with a base rare-earth-doped luminescent sublayer by the reflectance-enhanced increase in luminescence produced in regions containing buried delamination cracks. TBC temperature monitoring is demonstrated using the temperature-dependent decay time for luminescence originating from the specific coating depth associated with a rare-earth-doped luminescent sublayer. The design and implementation of these TBCs with integrated luminescent sublayers is discussed, including co-doping strategies to produce more penetrating near-infrared luminescence. It is demonstrated that integration of the rare-earth-doped sublayers is achieved with no reduction in TBC life. In addition, results for multilayer TBCs designed to also perform as radiation barriers are also presented.

Procedure for the formation of a coating on an object by polymerization by luminescent discharge

NASA Technical Reports Server (NTRS)

1979-01-01

The object to be coated was placed in a reaction area located in a luminescent discharge chamber. By introducing the polymerizable material in this reaction area and applying an electrical field to this reaction, a polymerized film was obtained on the coating object under controlled conditions. By the use of thermomechanical treatment on the object, the undesirable effects of discoloration, brittleness, and viscosity can be controlled.

Buried particulate organic carbon stimulates denitrification and nitrate retention in stream sediments at the groundwater-surface water interface

USGS Publications Warehouse

Stelzer, Robert S.; Scott, J. Thad; Bartsch, Lynn

2015-01-01

The interface between ground water and surface water in streams is a hotspot for N processing. However, the role of buried organic C in N transformation at this interface is not well understood, and inferences have been based largely on descriptive studies. Our main objective was to determine how buried particulate organic C (POC) affected denitrification and NO3− retention in the sediments of an upwelling reach in a sand-plains stream in Wisconsin. We manipulated POC in mesocosms inserted in the sediments. Treatments included low and high quantities of conditioned red maple leaves (buried beneath combusted sand), ambient sediment (sand containing background levels of POC), and a control (combusted sand). We measured denitrification rates in sediments by acetylene-block assays in the laboratory and by changes in N2 concentrations in the field using membrane inlet mass spectrometry. We measured NO3−, NH4+, and dissolved organic N (DON) retention as changes in concentrations and fluxes along groundwater flow paths in the mesocosms. POC addition drove oxic ground water to severe hypoxia, led to large increases in dissolved organic C (DOC), and strongly increased denitrification rates and N (NO3− and total dissolved N) retention relative to the control. In situ denitrification accounted for 30 to 60% of NO3− retention. Our results suggest that buried POC stimulated denitrification and NO3− retention by producing DOC and by creating favorable redox conditions for denitrification.

Addendum to `numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system'

USGS Publications Warehouse

Cui, T.J.; Chew, W.C.; Aydiner, A.A.; Wright, D.L.; Smith, D.V.; Abraham, J.D.

2000-01-01

Two numerical models to simulate an enhanced very early time electromagnetic (VETEM) prototype system that is used for buried-object detection and environmental problems are presented. In the first model, the transmitting and receiving loop antennas accurately analyzed using the method of moments (MoM), and then conjugate gradient (CG) methods with the fast Fourier transform (FFT) are utilized to investigate the scattering from buried conducting plates. In the second model, two magnetic dipoles are used to replace the transmitter and receiver. Both the theory and formulation are correct and the simulation results for the primary magnetic field and the reflected magnetic field are accurate.

Nanoscale Imaging of Light-Matter Coupling Inside Metal-Coated Cavities with a Pulsed Electron Beam.

PubMed

Moerland, Robert J; Weppelman, I Gerward C; Scotuzzi, Marijke; Hoogenboom, Jacob P

2018-05-02

Many applications in (quantum) nanophotonics rely on controlling light-matter interaction through strong, nanoscale modification of the local density of states (LDOS). All-optical techniques probing emission dynamics in active media are commonly used to measure the LDOS and benchmark experimental performance against theoretical predictions. However, metal coatings needed to obtain strong LDOS modifications in, for instance, nanocavities, are incompatible with all-optical characterization. So far, no reliable method exists to validate theoretical predictions. Here, we use subnanosecond pulses of focused electrons to penetrate the metal and excite a buried active medium at precisely defined locations inside subwavelength resonant nanocavities. We reveal the spatial layout of the spontaneous-emission decay dynamics inside the cavities with deep-subwavelength detail, directly mapping the LDOS. We show that emission enhancement converts to inhibition despite an increased number of modes, emphasizing the critical role of optimal emitter location. Our approach yields fundamental insight in dynamics at deep-subwavelength scales for a wide range of nano-optical systems.

Digital Mapping of Buried Pipelines with a Dual Array System

DOT National Transportation Integrated Search

2003-06-06

The objective of this research is to develop a non-invasive system for detecting, mapping, and inspecting ferrous and plastic pipelines in place using technology that combines and interprets measurements from ground penetrating radar and electromagne...

Littoral assessment of mine burial signatures (LAMBS): buried landmine/background spectral-signature analyses

NASA Astrophysics Data System (ADS)

Kenton, Arthur C.; Geci, Duane M.; Ray, Kristofer J.; Thomas, Clayton M.; Salisbury, John W.; Mars, John C.; Crowley, James K.; Witherspoon, Ned H.; Holloway, John H., Jr.

2004-09-01

The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies (ALRT) project's LAMBS effort is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 μm) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. LAMBS has expanded previously collected databases to littoral areas - primarily dry and wet sandy soils - where tidal, surf, and wind conditions can severely modify spectral signatures. At AeroSense 2003, we reported completion of three buried mine collections at an inland bay, Atlantic and Gulf of Mexico beach sites. We now report LAMBS spectral database analyses results using metrics which characterize the detection performance of general types of spectral detection algorithms. These metrics include mean contrast, spectral signal-to-clutter, covariance, information content, and spectral matched filter analyses. Detection performance of the buried land mines was analyzed with regard to burial age, background type, and environmental conditions. These analyses considered features observed due to particle size differences, surface roughness, surface moisture, and compositional differences.

Littoral Assessment of Mine Burial Signatures (LAMBS) buried land mine/background spectral signature analyses

USGS Publications Warehouse

Kenton, A.C.; Geci, D.M.; Ray, K.J.; Thomas, C.M.; Salisbury, J.W.; Mars, J.C.; Crowley, J.K.; Witherspoon, N.H.; Holloway, J.H.; Harmon R.S.Broach J.T.Holloway, Jr. J.H.

2004-01-01

The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies (ALRT) project's LAMBS effort is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 ??m) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. LAMBS has expanded previously collected databases to littoral areas - primarily dry and wet sandy soils - where tidal, surf, and wind conditions can severely modify spectral signatures. At AeroSense 2003, we reported completion of three buried mine collections at an inland bay, Atlantic and Gulf of Mexico beach sites.1 We now report LAMBS spectral database analyses results using metrics which characterize the detection performance of general types of spectral detection algorithms. These metrics include mean contrast, spectral signal-to-clutter, covariance, information content, and spectral matched filter analyses. Detection performance of the buried land mines was analyzed with regard to burial age, background type, and environmental conditions. These analyses considered features observed due to particle size differences, surface roughness, surface moisture, and compositional differences.

Analysis of buried interfaces in multilayer mirrors using grazing incidence extreme ultraviolet reflectometry near resonance edges.

PubMed

Sertsu, M G; Nardello, M; Giglia, A; Corso, A J; Maurizio, C; Juschkin, L; Nicolosi, P

2015-12-10

Accurate measurements of optical properties of multilayer (ML) mirrors and chemical compositions of interdiffusion layers are particularly challenging to date. In this work, an innovative and nondestructive experimental characterization method for multilayers is discussed. The method is based on extreme ultraviolet (EUV) reflectivity measurements performed on a wide grazing incidence angular range at an energy near the absorption resonance edge of low-Z elements in the ML components. This experimental method combined with the underlying physical phenomenon of abrupt changes of optical constants near EUV resonance edges enables us to characterize optical and structural properties of multilayers with high sensitivity. A major advantage of the method is to perform detailed quantitative analysis of buried interfaces of multilayer structures in a nondestructive and nonimaging setup. Coatings of Si/Mo multilayers on a Si substrate with period d=16.4  nm, number of bilayers N=25, and different capping structures are investigated. Stoichiometric compositions of Si-on-Mo and Mo-on-Si interface diffusion layers are derived. Effects of surface oxidation reactions and carbon contaminations on the optical constants of capping layers and the impact of neighboring atoms' interactions on optical responses of Si and Mo layers are discussed.

Coating for prevention of titanium combustion

NASA Technical Reports Server (NTRS)

Anderson, V. G.; Funkhouser, M.; Mcdaniel, P.

1980-01-01

A limited number of coating options for titanium gas turbine engine components were explored with the objective of minimizing potential combustion initiation and propagation without adversely affecting component mechanical properties. Objectives were met by two of the coatings, ion-plated platinum plus electroplated copper plus electroplated nickel and ion vapor deposited aluminum.

Acoustic and electromagnetic wave interaction in the detection and identification of buried objects

NASA Astrophysics Data System (ADS)

Lawrence, Daniel Edward

2002-09-01

In order to facilitate the development of a hybrid acoustic and electromagnetic (EM) system for buried object detection, a number of analytical solutions and a novel numerical technique are developed to analyze the complex interaction between acoustic and EM scattering. The essence of the interaction lies in the fact that identifiable acoustic properties of an object, such as acoustic resonances, can be observed in the scattered EM Doppler spectrum. Using a perturbation approach, analytical solutions are derived for the EM scattering from infinitely long circular cylinders, both metallic and dielectric, under acoustic vibration in a homogeneous background medium. Results indicate that both the shape variation and dielectric constant contribute to the scattered EM Doppler spectrum. To model the effect of a cylinder beneath an acoustically excited half-space, a new analytical solution is presented for EM scattering from a cylinder beneath a slightly rough surface. The solution is achieved by using plane-wave expansion of the fields and an iterative technique to account for the multiple interactions between the cylinder and rough surface. Following a similar procedure, a novel solution for elastic-wave scattering from a solid cylinder embedded in a solid half-space is developed and used to calculate the surface displacement. Simulations indicate that only a finite range of spatial surface frequencies, corresponding to surface roughness on the order of the EM wavelength; affect the EM scattering from buried objects and suggest that object detection can be improved if the acoustic excitation induces surface roughness outside this range. To extend the study to non-canonical scenarios, a novel numerical approach is introduced in which time-varying impedance boundary conditions (IBCs) are used in conjunction with the method of moments (MoM) to model the EM scattering from vibrating metallic objects of arbitrary shape. It is shown that the standard IBC provides a first order solution for TM polarization, but a second order IBC is needed for TE polarization. The crucial factor in the calculation of the potentially small Doppler components is that the time-varying nature of the cylinder boundary, contained within the surface impedance expressions, can be isolated from the unperturbed terms in the scattered field.

Photochemical Copper Coating on 3D Printed Thermoplastics

NASA Astrophysics Data System (ADS)

Yung, Winco K. C.; Sun, Bo; Huang, Junfeng; Jin, Yingdi; Meng, Zhengong; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-08-01

3D printing using thermoplastics has become very popular in recent years, however, it is challenging to provide a metal coating on 3D objects without using specialized and expensive tools. Herein, a novel acrylic paint containing malachite for coating on 3D printed objects is introduced, which can be transformed to copper via one-step laser treatment. The malachite containing pigment can be used as a commercial acrylic paint, which can be brushed onto 3D printed objects. The material properties and photochemical transformation processes have been comprehensively studied. The underlying physics of the photochemical synthesis of copper was characterized using density functional theory calculations. After laser treatment, the surface coating of the 3D printed objects was transformed to copper, which was experimentally characterized by XRD. 3D printed prototypes, including model of the Statue of Liberty covered with a copper surface coating and a robotic hand with copper interconnections, are demonstrated using this painting method. This composite material can provide a novel solution for coating metals on 3D printed objects. The photochemical reduction analysis indicates that the copper rust in malachite form can be remotely and photo-chemically reduced to pure copper with sufficient photon energy.

Photochemical Copper Coating on 3D Printed Thermoplastics

PubMed Central

Yung, Winco K. C.; Sun, Bo; Huang, Junfeng; Jin, Yingdi; Meng, Zhengong; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-01-01

3D printing using thermoplastics has become very popular in recent years, however, it is challenging to provide a metal coating on 3D objects without using specialized and expensive tools. Herein, a novel acrylic paint containing malachite for coating on 3D printed objects is introduced, which can be transformed to copper via one-step laser treatment. The malachite containing pigment can be used as a commercial acrylic paint, which can be brushed onto 3D printed objects. The material properties and photochemical transformation processes have been comprehensively studied. The underlying physics of the photochemical synthesis of copper was characterized using density functional theory calculations. After laser treatment, the surface coating of the 3D printed objects was transformed to copper, which was experimentally characterized by XRD. 3D printed prototypes, including model of the Statue of Liberty covered with a copper surface coating and a robotic hand with copper interconnections, are demonstrated using this painting method. This composite material can provide a novel solution for coating metals on 3D printed objects. The photochemical reduction analysis indicates that the copper rust in malachite form can be remotely and photo-chemically reduced to pure copper with sufficient photon energy. PMID:27501761

Photochemical Copper Coating on 3D Printed Thermoplastics.

PubMed

Yung, Winco K C; Sun, Bo; Huang, Junfeng; Jin, Yingdi; Meng, Zhengong; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-08-09

3D printing using thermoplastics has become very popular in recent years, however, it is challenging to provide a metal coating on 3D objects without using specialized and expensive tools. Herein, a novel acrylic paint containing malachite for coating on 3D printed objects is introduced, which can be transformed to copper via one-step laser treatment. The malachite containing pigment can be used as a commercial acrylic paint, which can be brushed onto 3D printed objects. The material properties and photochemical transformation processes have been comprehensively studied. The underlying physics of the photochemical synthesis of copper was characterized using density functional theory calculations. After laser treatment, the surface coating of the 3D printed objects was transformed to copper, which was experimentally characterized by XRD. 3D printed prototypes, including model of the Statue of Liberty covered with a copper surface coating and a robotic hand with copper interconnections, are demonstrated using this painting method. This composite material can provide a novel solution for coating metals on 3D printed objects. The photochemical reduction analysis indicates that the copper rust in malachite form can be remotely and photo-chemically reduced to pure copper with sufficient photon energy.

4 Metre diameter penstock construction for the Raymond Reservoir Hydro Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, H.D.; Alexander, M.

1995-12-31

A four metre diameter 770 m long buried steel penstock was constructed for the 20 MW Raymond Reservoir Hydro Project in southern Alberta. The penstock delivers up to 56.7 m{sup 3}/sec of irrigation water at an effective head of 44 m to a 2.6 m diameter Kaplan turbine. The hydro facility was commissioned in the spring of 1994. The steel pipe was delivered to the site in 18 m long sections from a fabrication plant located 250 km away. Specialized equipment was engineered and constructed to externally coat and internally line the pipe sections on site. The pipe sections, weighingmore » from 27,000 to 30,000 kg, were rolled and moved on a specially built lathe during the external sandblasting and tape wrapping operation. The external tape wrapping is one element of the cathodic protection system for the steel pipe. Specialized equipment was modified to sandblast the interior to white metal and then mechanically apply three coats of internal epoxy lining. The internal lining improves the hydraulic characteristics of the pipe in addition to protecting the pipe from corrosion. This innovative approach to coating and lining the pipe resulted in an exceptionally high quality product at an affordable cost.« less

Guided wave propagation in single and double layer hollow cylinders embedded in infinite media.

PubMed

Jia, Hua; Jing, Mu; Joseph, L Rose

2011-02-01

Millions of miles of pipes are being used for the transportation, distribution, and local use of petroleum products, gas, water, and chemicals. Most of the pipes are buried in soil, leading to the significance of the study on the subject of guided wave propagation in pipes with soil influence. Previous investigations of ultrasonic guided wave propagation in an elastic hollow cylinder and in an elastic hollow cylinder coated with a viscoelastic material have led to the development of inspection techniques for bare and coated pipes. However, the lack of investigation on guided wave propagation in hollow cylinders embedded in infinite media like soil has hindered the development of pipe inspection methods. Therefore the influence of infinite media on wave propagation is explored in this paper. Dispersion curves and wave structures of both axisymmetric and nonaxisymmetric wave modes are developed. Due to the importance of the convergence of numerical calculations, the requirements of thickness and element number of the finite soil layer between hollow cylinder and infinite element layer are discussed, and an optimal combination is obtained in this paper. Wave structures are used for the mode identification in the non-monotonic region caused by the viscoelastic properties of coating and infinite media.

Installation Restoration Program. Phase II. Confirmation/Quantification Stage 1 for George Air Force Base, California.

DTIC Science & Technology

1985-08-30

technology for objective assessment of adverse effects. A Phase III requirement can be identified at any time during the program. 4. Phase IV - Operations...earth’s field can be asso- ciated with naturally occurring materials, or buried iron objects and remnant cultural features associated with man’s...for as * adequately as that of its own personnel.I 2. Obviously, such objectives can be attained only by the cooperation of all concerned. Therefore, it

Cloaking of arbitrarily shaped objects with homogeneous coatings

NASA Astrophysics Data System (ADS)

Forestiere, Carlo; Dal Negro, Luca; Miano, Giovanni

2014-05-01

We present a theory for the cloaking of arbitrarily shaped objects and demonstrate electromagnetic scattering cancellation through designed homogeneous coatings. First, in the small-particle limit, we expand the dipole moment of a coated object in terms of its resonant modes. By zeroing the numerator of the resulting rational function, we accurately predict the permittivity values of the coating layer that abates the total scattered power. Then, we extend the applicability of the method beyond the small-particle limit, deriving the radiation corrections of the scattering-cancellation permittivity within a perturbation approach. Our method permits the design of invisibility cloaks for irregularly shaped devices such as complex sensors and detectors.

PLUTONIUM CLEANING PROCESS

DOEpatents

Kolodney, M.

1959-12-01

A method is described for rapidly removing iron, nickel, and zinc coatings from plutonium objects while simultaneously rendering the plutonium object passive. The method consists of immersing the coated plutonium object in an aqueous acid solution containing a substantial concentration of nitrate ions, such as fuming nitric acid.

A Continuous False Belief Task Reveals Egocentric Biases in Children and Adolescents with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Begeer, Sander; Bernstein, Daniel M.; van Wijhe, Jonas; Scheeren, Anke M.; Koot, Hans M.

2012-01-01

This study reports on a new false belief measure in a sample of 124 children and adolescents with or without high functioning autism (HFASD). In the classic paradigm, a participant predicts in which of two discrete locations a deceived protagonist will look for an object. In the current Sandbox task, the object is buried and reburied in a sandbox,…

GPR Imaging for Deeply Buried Objects: A Comparative Study Based on FDTD Models and Field Experiments

NASA Technical Reports Server (NTRS)

Tilley, roger; Dowla, Farid; Nekoogar, Faranak; Sadjadpour, Hamid

2012-01-01

Conventional use of Ground Penetrating Radar (GPR) is hampered by variations in background environmental conditions, such as water content in soil, resulting in poor repeatability of results over long periods of time when the radar pulse characteristics are kept the same. Target objects types might include voids, tunnels, unexploded ordinance, etc. The long-term objective of this work is to develop methods that would extend the use of GPR under various environmental and soil conditions provided an optimal set of radar parameters (such as frequency, bandwidth, and sensor configuration) are adaptively employed based on the ground conditions. Towards that objective, developing Finite Difference Time Domain (FDTD) GPR models, verified by experimental results, would allow us to develop analytical and experimental techniques to control radar parameters to obtain consistent GPR images with changing ground conditions. Reported here is an attempt at developing 20 and 3D FDTD models of buried targets verified by two different radar systems capable of operating over different soil conditions. Experimental radar data employed were from a custom designed high-frequency (200 MHz) multi-static sensor platform capable of producing 3-D images, and longer wavelength (25 MHz) COTS radar (Pulse EKKO 100) capable of producing 2-D images. Our results indicate different types of radar can produce consistent images.

Integrated magnetic, gravity, and GPR surveys to locate the probable source of hydrocarbon contamination in Sharm El-Sheikh area, south Sinai, Egypt

NASA Astrophysics Data System (ADS)

Morsy, Mona; Rashed, Mohamed

2013-01-01

Sharm El-Sheikh waters were suddenly hit by hydrocarbon spills which created a serious threat to the prosperous tourism industry in and around the city. Analysis of soil samples, water samples, and seabed samples collected in and around the contaminated bay area showed anomalous levels of hydrocarbons. An integrated geophysical investigation, using magnetic, gravity, and ground penetrating radar geophysical tools, was conducted in the headland overlooking the contaminated bay in order to delineate the possible subsurface source of contamination. The results of the geophysical investigations revealed three underground manmade reinforced concrete tanks and a complicated network of buried steel pipes in addition to other unidentified buried objects. The depths and dimensions of the discovered objects were determined. Geophysical investigations also revealed the presence of a north-south oblique slip fault running through the eastern part of the studied area. Excavations, conducted later on, confirmed the presence of one of the tanks delineated by the geophysical surveys.

Detecting gravesoil with headspace analysis with adsorption on short porous layer open tubular (PLOT) columns.

PubMed

Lovestead, Tara M; Bruno, Thomas J

2011-01-30

Victims of crimes are often buried in clandestine graves. There are several techniques for finding buried bodies or the scattered remains of a victim; however, none of these methods are very reliable or work in all scenarios. One way to detect gravesoil is to detect the biochemical changes of the surrounding soil due to cadaver decomposition, for example, the release of nitrogenous compounds. A simple and low-cost way to detect these compounds is based on the reaction of alpha amino groups with ninhydrin to form Ruhemann's purple. This test for ninhydrin-reactive nitrogen (NRN) has, to date, only been performed by direct solvent extraction of soil samples. Here, we present a method that detects trace quantities of NRN in the headspace air above gravesoil. Our method is based on an improved purge and trap method developed in our lab for sampling low volatility compounds, as well as volatile compounds at trace quantities, by applying low temperature collection on short alumina-coated porous layer open tubular (PLOT) columns. We modified this method to sample the headspace air above gravesoil with a motorized pipetter and a PLOT column at ambient temperatures. We generated gravesoil using rat cadavers and local soil. Trace quantities of NRN were successfully detected in the headspace air above gravesoil. We report the quantities of NRN recovered for buried rats, rats laid on top of soil, and blank graves (no rats) as a function of time (weeks to months). This work is the first (and thus far, only) example of a method for detecting NRN in the vapor phase, providing another tool for forensic investigators to aid in locating elusive clandestine graves. Published by Elsevier Ireland Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, E.E.; Welty, B.D.

Molten wax shows considerable promise as a fixative and dust control agent in demolition of radioactively contaminated facilities. Sticky molten wax, modified with special surfactants and wetting agents, is capable of not only coating materials but also penetrating into friable or dusty materials and making them incapable of becoming airborne during demolition. Wax also shows significant promise for stabilization of waste residuals that may be contained in buildings undergoing demolition. Some of the building materials that have been tested to date include concrete, wood, sheet rock, fiber insulation, lime, rock, and paper. Protective clothing, clay, sand, sulfur, and bentonite claymore » have been tested as surrogates for certain waste materials that may be encountered during building demolition. The paper describes several potential applications of molten wax for dust control in demolition of radioactive contaminated facilities. As a case-study, this paper describes a research test performed for a pipeline closure project being completed by the Idaho Cleanup Project at the Idaho National Laboratory. The project plans to excavate and remove a section of buried Duriron drain piping containing highly radioactive and friable and 'flighty' waste residuals. A full-scale pipeline mockup containing simulated waste was buried in sand to simulate the direct buried subsurface condition of the subject piping. The pipeline was pre-heated by drawing hot air through the line with a HEPA vacuum blower unit. Molten wax was pumped into the line and allowed to cool. The line was then broken apart in various places to evaluate the permeation performance of the wax. The wax fully permeated all the surrogate materials rendering them non-friable with a consistency similar to modeling clay. Based on the performance during the mockup, it is anticipated that the wax will be highly effective in controlling the spread of radiological contamination during pipe demolition activities. (authors)« less

Molecular and biochemical characterization of a highly stable bacterial laccase that occurs as a structural component of the Bacillus subtilis endospore coat.

PubMed

Martins, Ligia O; Soares, Claudio M; Pereira, Manuela M; Teixeira, Miguel; Costa, Teresa; Jones, George H; Henriques, Adriano O

2002-05-24

The Bacillus subtilis endospore coat protein CotA shows laccase activity. By using comparative modeling techniques, we were able to derive a model for CotA based on the known x-ray structures of zucchini ascorbate oxidase and Cuprinus cereneus laccase. This model of CotA contains all the structural features of a laccase, including the reactive surface-exposed copper center (T1) and two buried copper centers (T2 and T3). Single amino acid substitutions in the CotA T1 copper center (H497A, or M502L) did not prevent assembly of the mutant proteins into the coat and did not alter the pattern of extractable coat polypeptides. However, in contrast to a wild type strain, both mutants produced unpigmented colonies and spores unable to oxidize syringaldazine (SGZ) and 2'2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The CotA protein was purified to homogeneity from an overproducing Escherichia coli strain. The purified CotA shows an absorbance and a EPR spectra typical of blue multicopper oxidases. Optimal enzymatic activity was found at < or =pH 3.0 and at pH 7.0 for ABTS or SGZ oxidation, respectively. The apparent K(m) values for ABTS and SGZ at 37 degrees C were of 106 +/- 11 and 26 +/- 2 microm, respectively, with corresponding k(cat) values of 16.8 +/- 0.8 and 3.7 +/- 0.1 s(-1). Maximal enzyme activity was observed at 75 degrees C with ABTS as substrate. Remarkably, the coat-associated or the purified enzyme showed a half-life of inactivation at 80 degrees C of about 4 and 2 h, respectively, indicating that CotA is intrinsically highly thermostable.

Littoral assessment of mine burial signatures (LAMBS): buried-landmine hyperspectral data collections

NASA Astrophysics Data System (ADS)

Kenton, Arthur C.; Geci, Duane M.; McDonald, James A.; Ray, Kristofer J.; Thomas, Clayton M.; Holloway, John H., Jr.; Petee, Danny A.; Witherspoon, Ned H.

2003-09-01

The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies project's Littoral Assessment of Mine Burial Signatures (LAMBS) contract is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines located in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 μm) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. The LAMBS program further expands the hyperspectral database previously collected and analyzed on the U.S. Army's Hyperspectral Mine Detection Phenomenology program [see "Detection of Land Mines with Hyperspectral Data," and "Hyperspectral Mine Detection Phenomenology Program," Proc. SPIE Vol. 3710, pp 917-928 and 819-829, AeroSense April 1999] to littoral areas where tidal, surf, and wind action can additionally modify spectral signatures. This work summarizes the LAMBS buried mine collections conducted at three beach sites - an inland bay beach site (Eglin AFB, FL, Site A-22), an Atlantic beach site (Duck, NC), and a Gulf beach site (Eglin AFB, FL, Site A-15). Characteristics of the spectral signatures of the various dry and damp beach sands are presented. These are then compared to buried land mine signatures observed for the tested background types, burial ages, and environmental conditions experienced.

ENVIRONMENTAL TECHNOLOGY VERIFICATION COATINGS AND COATING EQUIPMENT PROGRAM (ETV CCEP), FINAL TECHNOLOGY APPLICATIONS GROUP TAGNITE--TESTING AND QUALITY ASSURANCE PLAN (T/QAP)

EPA Science Inventory

The overall objective of the Environmental Testing and Verification Coatings and Coating Equipment Program is to verify pollution prevention and performance characteristics of coating technologies and make the results of the testing available to prospective coating technology use...

Development and characterization of a stable adhesive bond between a poly(dimethylsiloxane) catheter material and a bacterial biofilm resistant acrylate polymer coating

PubMed Central

Tyler, Bonnie J.; Hook, Andrew; Pelster, Andreas; Williams, Paul; Alexander, Morgan; Arlinghaus, Heinrich F.

2017-01-01

Catheter associated urinary tract infections are the most common health related infections worldwide, contributing significantly to patient morbidity and mortality and increased health care costs. To reduce the incidence of these infections, new materials that resist bacterial biofilm formation are needed. A composite catheter material, consisting of bulk poly(dimethylsiloxane) (PDMS) coated with a novel bacterial biofilm resistant polyacrylate [ethylene glycol dicyclopentenyl ether acrylate (EGDPEA)-co-di(ethyleneglycol) methyl ether methacrylate (DEGMA)], has been proposed. The coated material shows excellent bacterial resistance when compared to commercial catheter materials, but delamination of the EGDPEA-co-DEGMA coatings under mechanical stress presents a challenge. In this work, the use of oxygen plasma treatment to improve the wettability and reactivity of the PDMS catheter material and improve adhesion with the EGDPEA-co-DEGMA coating has been investigated. Argon cluster three dimensional-imaging time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been used to probe the buried adhesive interface between the EGDPEA-co-DEGMA coating and the treated PDMS. ToF-SIMS analysis was performed in both dry and frozen-hydrated states, and the results were compared to mechanical tests. From the ToF-SIMS data, the authors have been able to observe the presence of PDMS, silicates, salt particles, cracks, and water at the adhesive interface. In the dry catheters, low molecular weight PDMS oligomers at the interface were associated with poor adhesion. When hydrated, the hydrophilic silicates attracted water to the interface and led to easy delamination of the coating. The best adhesion results, under hydrated conditions, were obtained using a combination of 5 min O2 plasma treatment and silane primers. Cryo-ToF-SIMS analysis of the hydrated catheter material showed that the bond between the primed PDMS catheter and the EGDPEA-co-DEGMA coating was stable in the presence of water. The resulting catheter material resisted Escherichia coli and Proteus mirabilis biofilm colonization by up to 95% compared with uncoated PDMS after 10 days of continuous bacterial exposure and had the mechanical properties necessary for use as a urinary catheter. PMID:28535686

Biological Observations on Aedes Seatoi Huang in Thailand with Notes on Rural Aedes Aegypti (L.) and Other Stegomyia Populations

DTIC Science & Technology

1972-03-15

distribution is herein extended by 6 provinces : Ang Thong, Chiang Mai , Lop Buri, Nakhon Sawan, Prachin Buri and Sara Buri (FIG. 1). These new...of Thailand : 1. Ang Thong. 2. Chiang Mai . 3. Chon Buri. 4. Kanchanaburi. 5. Lop Buri. 6. Nakhon Sawan. 7. Prachin Buri. 8. Sara Buri. Provinces

Buried landmine detection using multivariate normal clustering

NASA Astrophysics Data System (ADS)

Duston, Brian M.

2001-10-01

A Bayesian classification algorithm is presented for discriminating buried land mines from buried and surface clutter in Ground Penetrating Radar (GPR) signals. This algorithm is based on multivariate normal (MVN) clustering, where feature vectors are used to identify populations (clusters) of mines and clutter objects. The features are extracted from two-dimensional images created from ground penetrating radar scans. MVN clustering is used to determine the number of clusters in the data and to create probability density models for target and clutter populations, producing the MVN clustering classifier (MVNCC). The Bayesian Information Criteria (BIC) is used to evaluate each model to determine the number of clusters in the data. An extension of the MVNCC allows the model to adapt to local clutter distributions by treating each of the MVN cluster components as a Poisson process and adaptively estimating the intensity parameters. The algorithm is developed using data collected by the Mine Hunter/Killer Close-In Detector (MH/K CID) at prepared mine lanes. The Mine Hunter/Killer is a prototype mine detecting and neutralizing vehicle developed for the U.S. Army to clear roads of anti-tank mines.

Modelling a real-world buried valley system with vertical non-stationarity using multiple-point statistics

NASA Astrophysics Data System (ADS)

He, Xiulan; Sonnenborg, Torben O.; Jørgensen, Flemming; Jensen, Karsten H.

2017-03-01

Stationarity has traditionally been a requirement of geostatistical simulations. A common way to deal with non-stationarity is to divide the system into stationary sub-regions and subsequently merge the realizations for each region. Recently, the so-called partition approach that has the flexibility to model non-stationary systems directly was developed for multiple-point statistics simulation (MPS). The objective of this study is to apply the MPS partition method with conventional borehole logs and high-resolution airborne electromagnetic (AEM) data, for simulation of a real-world non-stationary geological system characterized by a network of connected buried valleys that incise deeply into layered Miocene sediments (case study in Denmark). The results show that, based on fragmented information of the formation boundaries, the MPS partition method is able to simulate a non-stationary system including valley structures embedded in a layered Miocene sequence in a single run. Besides, statistical information retrieved from the AEM data improved the simulation of the geology significantly, especially for the deep-seated buried valley sediments where borehole information is sparse.

Suggested Methods and Standards for Testing and Verification of Electromagnetic Buried Object Detectors

DTIC Science & Technology

1990-03-01

System .. ........................ 6-(Bl) vi LIST OF TAB.ES Pag e Table 4.1 Copper Test Objects ........ ..................... 4-3 Table 4.2...discriminate b hwtneri worthless aluminum or iron scraps and more valuable copper or silver 3-1 It is customary to analyze the reactions of search...or magnetite sand). Likewise, phase information can be used to discriminate (with the proper electronics) between aluminum alloy targets and copper

Examination of the mGluR mTOR Pathway for the Identification of Potential Therapeutic Targets To Treat Fragile X

DTIC Science & Technology

2016-11-01

Introduction Fragile X syndrome is the leading cause of intellectual disability resulting from a single gene mutation...performance, which measures motor learning and coordination. Treatment with metformin did not significantly affect performance in the rotarod task (Fig 5...marble burying, novel object recognition, object place memory, and reversal learning in the water Y maze (data not shown). It has been previously

The propagation and backscattering of soliton-like pulses in a chain of quartz beads and related problems. (II). Backscattering

NASA Astrophysics Data System (ADS)

Manciu, Marian; Sen, Surajit; Hurd, Alan J.

1999-12-01

We demonstrate that the propagation of solitons, soliton-like excitations and acoustic pulses discussed in the preceding article (M. Manciu, S. Sen and A.J. Hurd, Physica A, preceding article) can be used to detect buried impurities in a chain of elastic grains with Hertzian contacts. We also present preliminary data for 3D granular beds, where soliton-like objects can form and can be used to probe for buried impurities, thus suggesting that soliton-pulse spectroscopy has the potential to become a valuable tool for probing the structural properties of granular assemblies. The effects of restitution are briefly discussed. We refer to available experiments which support our contention.

Federal Highway Administration 100-year coating study.

DOT National Transportation Integrated Search

2012-11-01

The Federal Highway Administration 100-Year Coating Study was initiated in August 2009 to search for durable : coating systems at a reasonable cost. The objective of the study was to identify and evaluate coating materials that can : provide 100 year...

Ag out-surface diffusion in crystalline SiC with an effective SiO 2 diffusion barrier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xue, H.; Xiao, H. Y.; Zhu, Z.

2015-05-07

For applications of tristructural isotropic (TRISO) fuel particles in high temperature reactors, release of radioactive Ag isotope ( 110mAg) through the SiC coating layer is a safety concern. In order to understand the diffusion mechanism, Ag ion implantations near the surface and in the bulk were performed by utilizing different ion energies and energy-degrader foils. High temperature annealing was carried out on the as-irradiated samples to study the possible out-surface diffusion. Before and after annealing, Rutherford backscattering spectrometry (RBS) and secondary ion mass spectrometry (SIMS) measurements were employed to obtain the elemental profiles of the implanted samples. Our results suggestmore » little migration of buried Ag in the bulk, and an out-diffusion of the implanted Ag in the near-surface region of single crystal SiC. It is also found that a SiO 2 layer, which was formed during annealing, may serve as an effective barrier to reduce or prevent Ag out diffusion through the SiC coating layer.« less

Ag Out-surface Diffusion In Crystalline SiC With An Effective SiO2 Diffusion Barrier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xue, H.; Xiao, Haiyan Y.; Zhu, Zihua

2015-09-01

For applications of tristructural isotropic (TRISO) fuel particles in high temperature reactors, release of radioactive Ag isotope (110mAg) through the SiC coating layer is a safety concern. To understand the diffusion mechanism, Ag ion implantations near the surface and in the bulk were performed by utilizing different ion energies and energy-degrader foils. High temperature annealing was carried out on the as-irradiated samples to study the possible out-surface diffusion. Before and after annealing, Rutherford backscattering spectrometry (RBS) and secondary ion mass spectrometry (SIMS) measurements were employed to obtain the elemental profiles of the implanted samples. The results suggest little migration ofmore » buried Ag in the bulk, and an out-diffusion of the implanted Ag in the near-surface region of single crystal SiC. It is also found that a SiO2 layer, which was formed during annealing, may serve as an effective barrier to reduce or prevent Ag out diffusion through the SiC coating layer.« less

78 FR 72706 - Notice of Inventory Completion: Colorado State University, Fort Collins, CO

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-03

... bone beads buried with the adult female remains. Sometime during 1975, human remains representing, at... were identified. No associated funerary objects are present, although animal bone and a projectile.... Case 65 represents one partial individual mixed with bison bone. No known individuals were identified...

Palmer amaranth seed mortality in response to burial depth and time

USDA-ARS?s Scientific Manuscript database

Glyphosate resistant Palmer amaranth infests millions of arable acres in the SE US. One proposed method of reducing population numbers is to bury surface seeds deeply, below their optimal emergence zone. The objective of this study was to determine how burial longevity and depth impact Palmer amaran...

Scattering of Acoustic Waves from Ocean Boundaries

DTIC Science & Technology

2014-09-30

of buried mines and improve SONAR performance in shallow water. OBJECTIVES 1) Determination of the correct physical model of acoustic propagation...Nicholas Chotiros, particularly for theoretical development of bulk acoustic /sediment modeling and laser roughness measurements. REFERENCES C...PUBLICATIONS 1. M. Isakson, and N. Chotiros. Finite Element Modeling of Acoustic

Detection of disturbed earth using hyperspectral LWIR imaging data

NASA Astrophysics Data System (ADS)

Hubbard, Wendy; Bishop, Gary; Gagnon, Jean-Philippe; Lagueux, Philippe; Hannuna, Sion; Campbell, Neill

2010-10-01

The Reststrahlen effect has been investigated for detecting regions of recently disturbed earth, by taking images where metallic objects had been buried in a sandy soil and comparing with images of undisturbed soil. The images were taken with a Long wave Infrared (LWIR) Hyperspectral Sensor, the Hyper-Cam.

Monolithic echo-less photoconductive switches as a high-resolution detector for terahertz time-domain spectroscopy

NASA Astrophysics Data System (ADS)

Maussang, K.; Palomo, J.; Manceau, J.-M.; Colombelli, R.; Sagnes, I.; Li, L. H.; Linfield, E. H.; Davies, A. G.; Mangeney, J.; Tignon, J.; Dhillon, S. S.

2017-04-01

Interdigitated photoconductive (iPC) switches are powerful and convenient devices for time-resolved spectroscopy, with the ability to operate both as sources and detectors of terahertz (THz) frequency pulses. However, reflection of the emitted or detected radiation within the device substrate itself can lead to echoes that inherently limit the spectroscopic resolution achievable for their use in time-domain spectroscopy (TDS) systems. In this work, we demonstrate a design of low-temperature-grown-GaAs (LT-GaAs) iPC switches for THz pulse detection that suppresses such unwanted echoes. This is realized through the growth of a buried multilayer LT-GaAs structure that retains its ultrafast properties, which, after wafer bonding to a metal-coated host substrate, results in an iPC switch with a metal plane buried at a subwavelength depth below the LT-GaAs surface. Using this device as a detector, and coupling it to an echo-less iPC source, enables echo-free THz-TDS and high-resolution spectroscopy, with a resolution limited only by the temporal length of the measurement governed by the mechanical delay line used. As a proof-of-principle, the 212-221 and the 101-212 rotational lines of water vapor have been spectrally resolved, demonstrating a spectral resolution below 10 GHz.

Carbon decorative coatings by dip-, spin-, and spray-assisted layer-by-layer assembly deposition.

PubMed

Hong, Jinkee; Kang, Sang Wook

2011-09-01

We performed a comparative surface analysis of all-carbon nano-objects (multiwall carbon nanotubes (MWNT) or graphene oxide (GO) sheets) based multilayer coatings prepared using three widely used nanofilm fabrication methods: dip-, spin-, and spray-assisted layer-by-layer (LbL) deposition. The resultant films showed a marked difference in their growth mechanisms and surface morphologies. Various carbon decorative coatings were synthesized with different surface roughness values, despite identical preparation conditions. In particular, smooth to highly rough all-carbon surfaces, as determined by atomic force microscopy (AFM) and scanning electron microscopy (SEM), were readily obtained by manipulating the LbL deposition methods. As was confirmed by the AFM and SEM analyses, this finding indicated the fundamental morphological evolution of one-dimensional nano-objects (MWNT) and two-dimensional nano-objects (GO) by control of the surface roughness through the deposition method. Therefore, an analysis of the three LbL-assembly methods presented herein may offer useful information about the industrial use of carbon decorative coatings and provide an insight into ways to control the structures of multilayer coatings by tuning the morphologies of carbon nano-objects.

High-Frequency Sound Interaction with Ocean Sediments and with Objects in the Vicinity of the Water/Sediment Interface and Mid-Frequency Shallow Water Propagation and Scattering

DTIC Science & Technology

2007-09-30

combined with measured sediment properties, to test the validity of sediment acoustic models , and in particular the poroelastic (Biot) model . Addressing...TERM GOALS 1. Development of accurate models for acoustic scattering from, penetration into, and propagation within shallow water ocean sediments...2. Development of reliable methods for modeling acoustic detection of buried objects at subcritical grazing angles. 3. Improving our

Tapered monocapillary-optics for point source applications

DOEpatents

Hirsch, Gregory

2000-01-01

A glass or metal wire is precisely etched to form the paraboloidal or ellipsoidal shape of the final desired capillary optic. This shape is created by carefully controlling the withdrawal speed of the wire from an etchant bath. In the case of a complete ellipsoidal capillary, the etching operation is performed twice in opposite directions on adjacent wire segments. The etched wire undergoes a subsequent operation to create an extremely smooth surface. This surface is coated with a layer of material which is selected to maximize the reflectivity of the radiation. This reflective surface may be a single layer for wideband reflectivity, or a multilayer coating for optimizing the reflectivity in a narrower wavelength interval. The coated wire is built up with a reinforcing layer, typically by a plating operation. The initial wire is removed by either an etching procedure or mechanical force. Prior to removing the wire, the capillary is typically bonded to a support substrate. One option for attaching the wire to the substrate produces a monolithic structure by essentially burying it under a layer of plating which covers both the wire and the substrate. The capillary optic is used for efficiently collecting and redirecting the divergent radiation from a source which could be the anode of an x-ray tube, a plasma source, the fluorescent radiation from an electron microprobe, or some other source of radiation.

Shallow water imaging sonar system for environmental surveying. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-05-01

The scope of this research is to develop a shallow water sonar system designed to detect and map the location of objects such as hazardous wastes or discarded ordnance in coastal waters. The system will use high frequency wide-bandwidth imaging sonar, mounted on a moving platform towed behind a boat, to detect and identify objects on the sea bottom. Resolved images can be obtained even if the targets are buried in an overlayer of silt. The specific technical objective of this research was to develop and test a prototype system that is capable of (1) scan at high speeds (upmore » to 10m/s), even in shallow water (depth to ten meters), without motion blurring or loss of resolution; (2) produce images of the bottom structure that are detailed enough for unambiguous detection of objects as small as 15cm, even if they are buried up to 30cm deep in silt or sand. The critical technology involved uses an linear FM (LFM) or similar complex waveform, which has a high bandwidth for good range resolution, with a long pulse length for similar Dopper resolution. The lone duration signal deposits more energy on target than a narrower pulse, which increases the signal-to-noise ratio and signal-to-clutter ratio. This in turn allows the use of cheap, lightweight, low power, piezoelectric transducers at the 30--500 kHz range.« less

3D modeling of seismic waves propagation in the Israeli continental shelf: soft sediments, buried canyons and their effects.

NASA Astrophysics Data System (ADS)

Tsesarsky, M.; Volk, O.; Shani-Kadmiel, S.; Gvirtzman, Z.

2016-12-01

Sedimentary wedges underlay many coastal areas, specifically along passive continental margins. Although a large portion of the world`s population is concentrated along coastal areas, relatively few studies investigated the seismic hazard related to internal structure of these wedges. This is particularly important, when the passive margin is located in proximity to active plate boundaries. Sedimentry wedges have low angles compared to fault bounded basins, hence commonly treated using 1D methods. In various locations the sedimentary wedges are transected by deep buried canyons typically filled with sediments softer than their surrounding bedrock. Such structures are found is the Mediterranean coast of Israel. Here, a sedimentary wedge and buried canyons underlay some of the country's most densely populated regions. Seismic sources can be found both at sea and on land at epicentral distances ranging from 50 to 200 km. Although this region has a proven seismic record, it has, like many other parts of the world, limited instrumental coverage and long return periods. This makes assessment of ground motions in a future earthquake difficult and highlights the importance of non-instrumental methods. We employ numerical modeling (SW4 FD code) to study seismic ground motions and their amplification atop the sedimentary wedge and canyons. This goal is a part of a larger objective aiming at developing a systematic approach for distinction between individual contributions of basin structures to the highly complex overall basin response. We show that the sedimentary wedge and buried canyon both exhibit a unique response and modeling them as one-dimensional structures could significantly underestimate seismic hazard. The sedimentary wedge exhibit amplification ratios, relative to a horizontally layered model, up to a factor of 2. This is mainly due to the amplification of Rayleigh waves traveling into the wedge from its thin side. The buried canyon structure shows a simple, "easy to use" response with considerably high PGV values and amplification ratios of up to 3 along its axis. This response is due to a geometrical focusing effect caused by the convex shape of the canyon's floor. The canyon's response is significant even where the canyon is buried deep under the surface.

Thermal barrier coating life prediction model development

NASA Technical Reports Server (NTRS)

Demasi, J. T.; Sheffler, K. D.

1986-01-01

The objective of this program is to establish a methodology to predict Thermal Barrier Coating (TBC) life on gas turbine engine components. The approach involves experimental life measurement coupled with analytical modeling of relevant degradation modes. The coating being studied is a flight qualified two layer system, designated PWA 264, consisting of a nominal ten mil layer of seven percent yttria partially stabilized zirconia plasma deposited over a nominal five mil layer of low pressure plasma deposited NiCoCrAlY. Thermal barrier coating degradation modes being investigated include: thermomechanical fatigue, oxidation, erosion, hot corrosion, and foreign object damage.

Enzyme leaching of surficial geochemical samples for detecting hydromorphic trace-element anomalies associated with precious-metal mineralized bedrock buried beneath glacial overburden in northern Minnesota

USGS Publications Warehouse

Clark, Robert J.; Meier, A.L.; Riddle, G.; ,

1990-01-01

One objective of the International Falls and Roseau, Minnesota, CUSMAP projects was to develop a means of conducting regional-scale geochemical surveys in areas where bedrock is buried beneath complex glacially derived overburden. Partial analysis of B-horizon soils offered hope for detecting subtle hydromorphic trace-element dispersion patterns. An enzyme-based partial leach selectively removes metals from oxide coatings on the surfaces of soil materials without attacking their matrix. Most trace-element concentrations in the resulting solutions are in the part-per-trillion to low part-per-billion range, necessitating determinations by inductively coupled plasma/mass spectrometry. The resulting data show greater contrasts for many trace elements than with other techniques tested. Spatially, many trace metal anomalies are locally discontinuous, but anomalous trends within larger areas are apparent. In many instances, the source for an anomaly seems to be either basal till or bedrock. Ground water flow is probably the most important mechanism for transporting metals toward the surface, although ionic diffusion, electrochemical gradients, and capillary action may play a role in anomaly dispersal. Sample sites near the Rainy Lake-Seine River fault zone, a regional shear zone, often have anomalous concentrations of a variety of metals, commonly including Zn and/or one or more metals which substitute for Zn in sphalerite (Cd, Ge, Ga, and Sn). Shifts in background concentrations of Bi, Sb, and As show a trend across the area indicating a possible regional zoning of lode-Au mineralization. Soil anomalies of Ag, Co, and Tl parallel basement structures, suggesting areas that may have potential for Cobalt/Thunder Baytype silver viens. An area around Baudette, Minnesota, which is underlain by quartz-chlorite-carbonate-altered shear zones, is anomalous in Ag, As, Bi, Co, Mo, Te, Tl, and W. Anomalies of Ag, As, Bi, Te, and W tend to follow the fault zones, suggesting potential for lode-Au deposits. Soil anomalies of Co, Mo, and Tl appear to follow northwest-striking structures that cross the shear zones, suggesting that Thunder Bay-type mineralization may have overprinted earlier mineralization along the shear zones.

Coated substrate apparatus and method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bao, Zhenan; Diao, Ying; Mannsfeld, Stefan Christian Bernhardt

A coated substrate is formed with aligned objects such as small molecules, macromolecules and nanoscale particulates, such as inorganic, organic or inorganic/organic hybrid materials. In accordance with one or more embodiments, an apparatus or method involves an applicator having at least one surface patterned with protruded or indented features, and a coated substrate including a solution-based layer of objects having features and morphology attributes arranged as a function of the protruded or indented features.

Solid state television camera (CCD-buried channel)

NASA Technical Reports Server (NTRS)

1976-01-01

The development of an all solid state television camera, which uses a buried channel charge coupled device (CCD) as the image sensor, was undertaken. A 380 x 488 element CCD array is utilized to ensure compatibility with 525 line transmission and display monitor equipment. Specific camera design approaches selected for study and analysis included (a) optional clocking modes for either fast (1/60 second) or normal (1/30 second) frame readout, (b) techniques for the elimination or suppression of CCD blemish effects, and (c) automatic light control and video gain control (i.e., ALC and AGC) techniques to eliminate or minimize sensor overload due to bright objects in the scene. Preferred approaches were determined and integrated into a deliverable solid state TV camera which addressed the program requirements for a prototype qualifiable to space environment conditions.

Solid state television camera (CCD-buried channel), revision 1

NASA Technical Reports Server (NTRS)

1977-01-01

An all solid state television camera was designed which uses a buried channel charge coupled device (CCD) as the image sensor. A 380 x 488 element CCD array is utilized to ensure compatibility with 525-line transmission and display monitor equipment. Specific camera design approaches selected for study and analysis included (1) optional clocking modes for either fast (1/60 second) or normal (1/30 second) frame readout, (2) techniques for the elimination or suppression of CCD blemish effects, and (3) automatic light control and video gain control techniques to eliminate or minimize sensor overload due to bright objects in the scene. Preferred approaches were determined and integrated into a deliverable solid state TV camera which addressed the program requirements for a prototype qualifiable to space environment conditions.

Solid state, CCD-buried channel, television camera study and design

NASA Technical Reports Server (NTRS)

Hoagland, K. A.; Balopole, H.

1976-01-01

An investigation of an all solid state television camera design, which uses a buried channel charge-coupled device (CCD) as the image sensor, was undertaken. A 380 x 488 element CCD array was utilized to ensure compatibility with 525 line transmission and display monitor equipment. Specific camera design approaches selected for study and analysis included (a) optional clocking modes for either fast (1/60 second) or normal (1/30 second) frame readout, (b) techniques for the elimination or suppression of CCD blemish effects, and (c) automatic light control and video gain control techniques to eliminate or minimize sensor overload due to bright objects in the scene. Preferred approaches were determined and integrated into a design which addresses the program requirements for a deliverable solid state TV camera.

Self-locking threaded fasteners

DOEpatents

Glovan, Ronald J.; Tierney, John C.; McLean, Leroy L.; Johnson, Lawrence L.

1996-01-01

A threaded fastener with a shape memory alloy (SMA) coatings on its threads is disclosed. The fastener has special usefulness in high temperature applications where high reliability is important. The SMA coated fastener is threaded into or onto a mating threaded part at room temperature to produce a fastened object. The SMA coating is distorted during the assembly. At elevated temperatures the coating tries to recover its original shape and thereby exerts locking forces on the threads. When the fastened object is returned to room temperature the locking forces dissipate. Consequently the threaded fasteners can be readily disassembled at room temperature but remains securely fastened at high temperatures. A spray technique is disclosed as a particularly useful method of coating of threads of a fastener with a shape memory alloy.

Thermal barrier coating life prediction model

NASA Technical Reports Server (NTRS)

Pilsner, B. H.; Hillery, R. V.; Mcknight, R. L.; Cook, T. S.; Kim, K. S.; Duderstadt, E. C.

1986-01-01

The objectives of this program are to determine the predominant modes of degradation of a plasma sprayed thermal barrier coating system, and then to develop and verify life prediction models accounting for these degradation modes. The program is divided into two phases, each consisting of several tasks. The work in Phase 1 is aimed at identifying the relative importance of the various failure modes, and developing and verifying life prediction model(s) for the predominant model for a thermal barrier coating system. Two possible predominant failure mechanisms being evaluated are bond coat oxidation and bond coat creep. The work in Phase 2 will develop design-capable, causal, life prediction models for thermomechanical and thermochemical failure modes, and for the exceptional conditions of foreign object damage and erosion.

Parameterisation of non-homogeneities in buried object detection by means of thermography

NASA Astrophysics Data System (ADS)

Stepanić, Josip; Malinovec, Marina; Švaić, Srećko; Krstelj, Vjera

2004-05-01

Landmines and their natural environment form a system of complex dynamics with variable characteristics. A manifestation of that complexity within the context of thermography-based landmines detection is excessive noise in thermograms. That has severely suppressed application of thermography in landmines detection for the purposes of humanitarian demining. (To be differentiated from military demining and demining for military operations other than war [Land Mine Detection DOD's Research Program Needs a Comprehensive Evaluation Strategy, US GAO Report, GAO-01 239, 2001; International Mine Action Standards, Chapter 4.--Glossary. Available at: < http://www.mineactionstandards.org/IMAS_archive/Final/04.10.pdf>].) The discrepancy between the existing role and the actual potential of thermography in humanitarian demining motivated systematic approach to sources of noise in thermograms of buried objects. These sources are variations in mine orientation relative to soil normal, which modify the shape of mine signature on thermograms, as well as non-homogeneities in soil and vegetation layer above the mine, which modify the overall quality of thermograms. This paper analyses the influence of variable mines, and more generally the influence of axially symmetric buried object orientation on the quality of its signature on thermograms. The following two angles have been extracted to serve as parameters describing variation in orientation: (i) θ--angle between the local vertical axis and mine symmetry axis and (ii) ψ--angle between local vertical axis and soil surface normal. Their influence is compared to the influence of (iii) d--the object depth change, which serves as control parameter. The influences are quantified and ranked within a statistically planned experiment. The analysis has proved that among the parameters listed, the most influential one is statistical interaction dψ, followed with the statistical interaction dθ. According to statistical tests, these two combinations are considered the most significant influences. The results show that the currently applied analysis of thermography in humanitarian demining must be broadened by the inclusion of the variations in mine orientation, otherwise a decrease in the probability of mine detection, due to the presence of a systematic error, occurs.

GPR detectability of rocks in a Martian-like shallow subsoil: A numerical approach

NASA Astrophysics Data System (ADS)

Valerio, Guido; Galli, Alessandro; Matteo Barone, Pier; Lauro, Sebastian E.; Mattei, Elisabetta; Pettinelli, Elena

2012-03-01

In this work, the ability of Ground Penetrating Radar (GPR) to detect rocks buried in composite soil is studied in connection with the planned ExoMars mission, as GPR will be used during this mission to scan the Martian subsurface to help define feasible sites for shallow drilling. A realistic model of the operating environment is implemented through a full-wave electromagnetic simulator, taking into account the antenna system and the signal features. The flexibility and efficiency of this numerical approach has allowed for the analysis of a great variety of configurations. The regolith is modeled based on data from recent explorations, while various kinds of embedded rocks are considered that have different geometrical and physical characteristics. The simulated results are compared with ad hoc GPR measurements performed on basalts buried in a mixture of glass beads, as an analogue of a dry sandy Martian soil. A very good agreement between theoretical and experimental results is found, thus validating the proposed numerical approach. This research has defined useful and reliable information concerning the prediction of scattering effects from buried objects in the environment where the ExoMars rover will operate.

Near-specular acoustic scattering from a buried submarine mud volcano.

PubMed

Gerig, Anthony L; Holland, Charles W

2007-12-01

Submarine mud volcanoes are objects that form on the seafloor due to the emission of gas and fluidized sediment from the Earth's interior. They vary widely in size, can be exposed or buried, and are of interest to the underwater acoustics community as potential sources of active sonar clutter. Coincident seismic reflection data and low frequency bistatic scattering data were gathered from one such buried mud volcano located in the Straits of Sicily. The bistatic data were generated using a pulsed piston source and a 64-element horizontal array, both towed over the top of the volcano. The purpose of this work was to appropriately model low frequency scattering from the volcano using the bistatic returns, seismic bathymetry, and knowledge of the general geoacoustic properties of the area's seabed to guide understanding and model development. Ray theory, with some approximations, was used to model acoustic propagation through overlying layers. Due to the volcano's size, scattering was modeled using geometric acoustics and a simple representation of volcano shape. Modeled bistatic data compared relatively well with experimental data, although some features remain unexplained. Results of an inversion for the volcano's reflection coefficient indicate that it may be acoustically softer than expected.

Behavioral Characteristics of Ubiquitin-Specific Peptidase 46-Deficient Mice

PubMed Central

Imai, Saki; Kano, Makoto; Nonoyama, Keiko; Ebihara, Shizufumi

2013-01-01

We have previously identified Usp46, which encodes for ubiquitin-specific peptidase 46, as a quantitative trait gene affecting the immobility time of mice in the tail suspension test (TST) and forced swimming test. The mutation that we identified was a 3-bp deletion coding for lysine (Lys 92), and mice with this mutation (MT mice), as well as Usp46 KO mice exhibited shorter TST immobility times. Behavioral pharmacology suggests that the gamma aminobutyric acid A (GABAA) receptor is involved in regulating TST immobility time. In order to understand how far Usp46 controls behavioral phenotypes, which could be related to mental disorders in humans, we subjected Usp46 MT and KO mice to multiple behavioral tests, including the open field test, ethanol preference test, ethanol-induced loss of righting reflex test, sucrose preference test, novelty-suppressed feeding test, marble burying test, and novel object recognition test. Although behavioral phenotypes of the Usp46 MT and KO mice were not always identical, deficiency of Usp46 significantly affected performance in all these tests. In the open field test, activity levels were lower in Usp46 KO mice than wild type (WT) or MT mice. Both MT and KO mice showed lower ethanol preference and shorter recovery times after ethanol administration. Compared to WT mice, Usp46 MT and KO mice exhibited decreased sucrose preference, took longer latency periods to bite pellets, and buried more marbles in the sucrose preference test, novelty-suppressed feeding test, and marble burying test, respectively. In the novel object recognition test, neither MT nor KO mice showed an increase in exploration of a new object 24 hours after training. These findings indicate that Usp46 regulates a wide range of behavioral phenotypes that might be related to human mental disorders and provides insight into the function of USP46 deubiquitinating enzyme in the neural system. PMID:23472206

Initial Parameters of Neutron Stars

NASA Astrophysics Data System (ADS)

Popov, S. B.; Turolla, R.

2012-12-01

A subpopulation of neutron stars (NSs), known as central compact objects (CCOs) in supernova remnants, are suspected to be low-field objects basing on P - ṗ measurements for three of them. The birth rate of low-field NSs is probably comparable with the birth rate of normal radio pulsars. However, among compact objects in High-Mass X-ray Binaries (HMXBs) we do not see robust candidates for low-field NSs. We propose that this contradiction can be solved if magnetic fields of CCOs was buried due to strong fall-back, and then the field emerges on the time scale 104 -105 yrs.

3D mapping of buried rocks by the GPR WISDOM/ExoMars 2020

NASA Astrophysics Data System (ADS)

Herve, Yann; Ciarletti, Valerie; Le Gall, Alice; Quantin, Cathy; Guiffaut, Christophe; Plettemeier, Dirk

2017-04-01

The main objective of ExoMars 2020 is to search for signs of past and/or present life on Mars. Because these signs may be beneath the inhospitable surface of Mars, the ExoMars Rover has on board a suite of instruments aiming at characterizing the subsurface. In particular, the Rover payload includes WISDOM (Water Ice Subsurface Deposits Observation on Mars), a polarimetric ground penetrating radar designed to investigate the shallow subsurface. WISDOM is able to probe down to a depth of few meters with a resolution of few centimeters; its main objective is to provide insights into the geological context of the investigated Martian sites and to determine the most promising location to collect samples for the ExoMars drill. In this paper, we demonstrate the ability of WISDOM to locate buried rocks and to estimate their size distribution. Indeed, the rock distribution is related to the geological processes at play in the past or currently and thus provides clues to understand the geological context of the investigated site. Rocks also represent a hazard for drilling operations that WISDOM is to guide. We use a 3D FDTD code called TEMSI-FD (which takes into account the radiation pattern of the antenna system) to simulate WISDOM operations on a realistic (both in terms of dielectric properties and structure) ground. More specifically, our geoelectrical models of the Martian subsurface take into account realistic values of the complex permittivity relying on published measurements performed in laboratory on Martian analogues. Further, different distributions of buried rocks are considered based on the size-frequency distribution observed at the Mars Pathfinder landing site and on Oxia Planum, the landing site currently selected for ExoMars 2020. We will describe the algorithm we developed to automatically detect the signature of the buried rocks on radargrams. The radargrams are obtained simulating WISDOM operations along parallel and perpendicular profiles as planned for the ExoMars mission. Our ultimate goal is to show that WISDOM observations can be used to build a 3D map of the subsurface. We will also present experimental data obtained with a prototype of WISDOM to test our method.

Radiation Control Coatings Installed on Federal Buildings at Tyndall Air Force Base

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaba, R.L.; Petrie, T.W.

1999-03-16

The technical objectives of this CRADA comprise technology deployment and energy conservation efforts with the radiation control coatings industry and the utility sector. The results of this collaboration include a high-level data reporting, analysis and management system to support the deployment efforts. The technical objectives include successfully install, commission, operate, maintain and document the performance of radiation control coatings on roofs at Tyndall AFB and the Buildings Technology Center at the Oak Ridge National Laboratory; determine the life cycle savings that can be achieved by using radiation control coatings on entire roofs at Tyndall AFB, based on documented installed costmore » and operating maintenance costs with and without the coatings; determine if any specific improvements are required in the coatings before they can be successfully deployed in the federal sector; determine the most effective way to facilitate the widespread and rapid deployment of radiation control coatings in the federal sector; and clearly define any barriers to deployment.« less

Development of a Repeatable Protocol to Uniformly Coat Internal Complex Geometries of Fine Featured 3D Printed Objects with Ceramic Material, including Determination of Viscosity Limits to Properly Coat Certain Pore Sizes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rogers, A.

HEPA filters are commonly used in air filtration systems ranging in application from simple home systems to the more advanced networks used in research and development. Currently, these filters are most often composed of glass fibers with diameter on the order of one micron with polymer binders. These fibers, as well as the polymers used, are known to be fragile and can degrade or become extremely brittle with heat, severely limiting their use in high temperature applications. Ceramics are one promising alternative and can enhance the filtration capabilities compared to the current technology. Because ceramic materials are more thermally resistantmore » and chemically stable, there is great interest in developing a repeatable protocol to uniformly coat fine featured polymer objects with ceramic material for use as a filter. The purpose of this experiment is to determine viscosity limits that are able to properly coat certain pore sizes in 3D printed objects, and additionally to characterize the coatings themselves. Latex paint was used as a surrogate because it is specifically designed to produce uniform coatings.« less

High wear resistance of femoral components coated with titanium nitride: a retrieval analysis.

PubMed

Fabry, Christian; Zietz, Carmen; Baumann, Axel; Ehall, Reinhard; Bader, Rainer

2017-05-20

The objective of this study was to evaluate the in vivo wear resistance of cobalt-chromium femoral components coated with titanium nitride (TiN). Our null hypothesis was that the surface damage and the thickness of the TiN coating do not correlate with the time in vivo. Twenty-five TiN-coated bicondylar femoral retrievals with a mean implantation period of 30.7 ± 11.7 months were subjected to an objective surface damage analysis with a semi-quantitative assessment method. A visual examination of scratches, indentations, notches and coating breakthroughs of the surfaces was performed. The roughness and the coating thickness of the TiN coating were evaluated in the main articulation regions. Narrow scratches and indentations in the range of low flexion angles on the retrieval surfaces were the most common modes of damage. There was no evidence of delamination on the articulation surface but rather at the bottom of isolated severe indentations or notches. An analysis of three retrievals revealed a coating breakthrough in the patellofemoral joint region, resulting from patella maltracking and a dislocation. The arithmetical mean roughness of the TiN surface slightly increased with the implantation period. In contrast, the maximum peak height of the roughness profile was reduced at the condyles of the retrieved components in comparison with new, unused surfaces. No significant association between the coating thickness and implantation period was determined. Moreover, the measured values were retained in the range of the initial coating thickness even after several years of in vivo service. As was demonstrated by the results of this study, the surface damage to the TiN coating did not deteriorate with the implantation period. The calculated damage scores and the measured coating thickness in particular both confirmed that the TiN coating provides low wear rates. Our findings support the use of wear-resistant TiN-coated components in total knee arthroplasty with the objective of reducing the risk of aseptic loosening. However, in terms of TiN-coated femoral components, particular attention should be paid to a correct patellar tracking in order to avoid wear propagation at the implant.

Closure Report for CAU No. 430: Buried Depleted Uraniuim Artillery Round No. 1, Tonopah Test Range, Revision 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1997-02-25

1.1 Purpose This Closure Report presents the information obtained from investigative actions performed to justify the decision for clean closure of CAU 430 through "No Further Action." The investigative actions were performed per the Streamlined Approach for Environmental Restoration Plan, CA UNO. 430: Buried Depleted Uranium Artille~ Round No. 1, Tonopah Test Range (DOE/NV, 1996a) (hereafter referred to as the SAFER Plan). The Buried DU Artillery Round No. 1 is located approximately 1.1 kilometers (km) (0.7 mile [mi]) south of Avenue 13 in the test area south of Area 9 (Figure 1-2). The site was thought to consist of amore » potentially unexploded W-79 Joint Test Assembly (JTA) test artillery projectile with high explosives (HE) and DU. The DU was substituted for Special Nuclear Material to prevent a nuclear explosion and yet retain the physical characteristics of uranium for ballistic and other mechanical tests. The projectile was reportedly buried in one pit, approximately 5 to 10 feet (ft) deep (Smith, 1993; Smith, 1996; Quas, 1996). The exact location of the burial pit is unknown; however, three disturbed areas (Sites A, B, and C) were identified through geophysical surveys, site visits, and employee interviews as possible locations of the test projectile (Figure 1-3). Results of the investigation are summarized within this Closure Report. Additional information about the site and investigation activities may be found in the SAFER Plan (DOE/NV, 1996a). 1.2 Scope The objectives of the SAFER Plan (DOE/NV, 1996a) activities were to prepare the site for closure through locating and identi~ing the projectile (Buried DU Artillery Round No. 1), destroying the projectile and any remaining components, collecting soil samples to detect residual contamination resulting from projectile destruction, and finally, remediating residual contamination.« less

Investigation of environmental effects on coatings for thermal control of large space vehicles

NASA Technical Reports Server (NTRS)

Zerlaunt, G. A.; Gilligan, J. E.; Ashford, N. A.

1971-01-01

The objective of significantly advancing the state-of-the-art of white, spacecraft-radiator coatings has been realized in a comprehensive goal-oriented, pigmented-coatings research program. Considered were inorganic pigments and coatings, silicone polymers and coatings, the design and construction of a combined ultraviolet-plus-proton irradiation facility, the development of zinc orthotitanate pigment and coatings, and the effects on several low alpha sub s/epsilon paints of combined ultraviolet and proton irradiation.

Self-locking threaded fasteners

DOEpatents

Glovan, R.J.; Tierney, J.C.; McLean, L.L.; Johnson, L.L.

1996-01-16

A threaded fastener with a shape memory alloy (SMA) coatings on its threads is disclosed. The fastener has special usefulness in high temperature applications where high reliability is important. The SMA coated fastener is threaded into or onto a mating threaded part at room temperature to produce a fastened object. The SMA coating is distorted during the assembly. At elevated temperatures the coating tries to recover its original shape and thereby exerts locking forces on the threads. When the fastened object is returned to room temperature the locking forces dissipate. Consequently the threaded fasteners can be readily disassembled at room temperature but remains securely fastened at high temperatures. A spray technique is disclosed as a particularly useful method of coating of threads of a fastener with a shape memory alloy. 13 figs.

Longevity of shallow subsurface drip irrigation tubing under three tillage practices

USDA-ARS?s Scientific Manuscript database

Shallow Sub-Surface drip irrigation (S3DI) has drip tubing buried about 2-in below the soil surface. It is unknown how long drip tubing would be viable at this shallow soil depth using strip- or no-tillage systems. The objectives were to determine drip tube longevity, resultant crop yield, and parti...

Performance evaluation of seal coat materials and designs.

DOT National Transportation Integrated Search

2011-01-01

"This project presents an evaluation of seal coat materials and design method. The primary objectives of this research are 1) to evaluate seal coat performance : from various combinations of aggregates and emulsions in terms of aggregate loss; 2) to ...

Resonant Soft X-ray Scattering as a Powerful Probe of Buried Polymer Interfaces

NASA Astrophysics Data System (ADS)

Chen, Wei; Jiang, Zhang; Tirrell, Matthew

Elucidation of polymer interfacial structures provides insights into interfacial molecular mechanisms for coating protection, adhesion, lubrication, friction, wettability, biocompatibility, and even charge transport properties. Resonant Soft X-ray Scattering (RSoXS) offers a unique element, site and valence specific probe to study spatial modulations of molecular orbital degrees of freedom on the nanoscopic length scale. This unique sensitivity is achieved by merging small angle x-ray scattering and x-ray absorption spectroscopy into a single experiment, where the scattering provides information about spatial modulations and the spectroscopy provides sensitivity to the molecular anisotropy. Here we applied RSoXS to polystyrene (PS) films at solid-solid interfaces and poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) brushes at solid-liquid interfaces. It is found that the interfacial width of PS thin film is about one order of magnitude large than those observed by traditional scattering techniques. In addition, although the ion-induced changes of PMPC thickness are not apparent in aqueous solutions, their chain conformations like polyzwitterion distribution and correlation varied, dependent on salt types, ionic strengths and ion valences. Consequently, it is evident that RSoXS is a powerful probe of buried polymer interlaces with both spatial and chemical sensitivities. This work was supported by the U.S. Department of Energy, Office of Science, Program in Basic Energy Sciences, Division of Materials Science and Engineering.

Strain Compatible Oxidation and Corrosion Protection Coatings for Enhanced Thermo-Mechanical Durability of Turbine Airfoils

DTIC Science & Technology

2011-12-05

Report: Grant N00014-08-0331 Technical Objectives As critical components of advanced aircraft engines , turbine airfoils require coatings for...advanced aircrafi engines , turbine airfoils require coatings for enhancement of oxidation, corrosion and thermal capabilities . Airfoil coatings ofien...Oxidation and Corrosion Protection Coatings for Enhanced Thermo-Mechanical Durability of Turbine Airfoils 5b. GRANT NUMBER N00014-08-l-0331 5c

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, E.E.

Molten wax shows considerable promise as a fixative and dust control agent in demolition of radioactively contaminated facilities. Sticky molten wax, modified with special surfactants and wetting agents, is capable of not only coating materials but also penetrating into friable or dusty materials and making them incapable of becoming airborne during demolition. Wax also shows significant promise for stabilization of waste residuals that may be contained in buildings undergoing demolition. Some of the building materials that have been tested to date include concrete, wood, sheet-rock, fiber insulation, lime, rock, and paper. Protective clothing, clay, sand, sulfur, and bentonite clay havemore » been tested as surrogates for certain waste materials that may be encountered during building demolition. The paper describes several potential applications of molten wax for dust control in demolition of radioactive contaminated facilities. As a case-study, this paper describes a research test performed for a pipeline closure project being completed by the Idaho Cleanup Project at the Idaho National Laboratory. The project plans to excavate and remove a section of buried Duriron drain piping containing highly radioactive and friable and 'flighty' waste residuals. A full-scale pipeline mockup containing simulated waste was buried in sand to simulate the direct-buried subsurface condition of the subject piping. The pipeline was pre-heated by drawing hot air through the line with a HEPA vacuum blower unit. Molten wax was pumped into the line and allowed to cool. The line was then broken apart in various places to evaluate the permeation performance of the wax. The wax fully permeated all the surrogate materials rendering them non-friable with a consistency similar to modeling clay. Based on the performance during the mockup, it is anticipated that the wax will be highly effective in controlling the spread of radiological contamination during pipe demolition activities. A larger test was completed this year to simulate the work in more realistic conditions. (authors)« less

Detection and quantification of hydrocarbons in sediments

USGS Publications Warehouse

Wynn, Jeff; Williamson, Mike; Frank, Jeff

2016-01-01

A new technology developed by the US Geological Survey now allows for fast, direct detection of hydrocarbon plumes both in rivers and drifting in the deep ocean. Recent experiments show that the method can also detect and quantify hydrocarbons buried in river sediments and estuaries. This approach uses a variant of induced polarization, a surface-sensitive physical property of certain polarizable materials immersed in an electrolyte that can accept and adsorb charge under an inducing voltage. Known polarizable materials include most sulfides, ilmenite (FeTiO3), metallic objects such as buried wrecks and pipelines, and now hydrocarbons. The hydrocarbon-in-water response to induced polarization is in fact nearly two orders of magnitude greater than the IP response of any of the hard minerals. The oil:water detection limit for hydrocarbons so far is down to 0.0002% in the laboratory.

Ground-water data for the alluvial, buried channel, Basel Pleistocene and Dakota aquifer in West-Central Iowa

USGS Publications Warehouse

Hunt, Pamela K.B.; Runkle, Donna L.

1985-01-01

The purpose of this investigation was to determine the availability, quantity and quality of groundwater from three principal aquifers in West-Central Iowa, the alluvial, buried channel, Basal Pleistocene and the Dakota aquifers. Specific objectives were to: (1) determine the location, extent and the nature of these aquifers; (2) evaluate the occurrence and movement of groundwater, including the sources of recharge and discharge; (3) estimate the quantities of water stored in the aquifers; (4) estimate the potential yields of wells tapping the aquifers; (5) estimate the water use; and (6) describe the chemical quality of the groundwater. This report is the compilation of the data collected during the investigation and has the purpose of providing a reference for an interpretive report describing groundwater resources and a bedrock topography map of the study area.

Investigation of an EMI sensor for detection of large metallic objects in the presence of metallic clutter

NASA Astrophysics Data System (ADS)

Black, Christopher; McMichael, Ian; Riggs, Lloyd

2005-06-01

Electromagnetic induction (EMI) sensors and magnetometers have successfully detected surface laid, buried, and visually obscured metallic objects. Potential military activities could require detection of these objects at some distance from a moving vehicle in the presence of metallic clutter. Results show that existing EMI sensors have limited range capabilities and suffer from false alarms due to clutter. This paper presents results of an investigation of an EMI sensor designed for detecting large metallic objects on a moving platform in a high clutter environment. The sensor was developed by the U.S. Army RDECOM CERDEC NVESD in conjunction with the Johns Hopkins University Applied Physics Laboratory.

The spatial distribution the thickness of polymer powder coatings for ultrasonic sensors

NASA Astrophysics Data System (ADS)

Gavrilova, V. A.; Fazlyyyakhmatov, M. G.; Kashapov, N. F.

2014-11-01

Objects of research are coatings and technology of their applying to the piezoelectric elements for ultrasound. Results of studies the distribution coating thickness according to different modes of coating process are presented. Experimentally confirmed the simulation results of the movement gas suspension on the electrostatic field in the electrode system "needle - plane".

Burying Dogs in Ancient Cis-Baikal, Siberia: Temporal Trends and Relationships with Human Diet and Subsistence Practices

PubMed Central

Losey, Robert J.; Garvie-Lok, Sandra; Leonard, Jennifer A.; Katzenberg, M. Anne; Germonpré, Mietje; Nomokonova, Tatiana; Sablin, Mikhail V.; Goriunova, Olga I.; Berdnikova, Natalia E.; Savel’ev, Nikolai A.

2013-01-01

The first objective of this study is to examine temporal patterns in ancient dog burials in the Lake Baikal region of Eastern Siberia. The second objective is to determine if the practice of dog burial here can be correlated with patterns in human subsistence practices, in particular a reliance on terrestrial mammals. Direct radiocarbon dating of a suite of the region’s dog remains indicates that these animals were given burial only during periods in which human burials were common. Dog burials of any kind were most common during the Early Neolithic (∼7–8000 B.P.), and rare during all other time periods. Further, only foraging groups seem to have buried canids in this region, as pastoralist habitation sites and cemeteries generally lack dog interments, with the exception of sacrificed animals. Stable carbon and nitrogen isotope data indicate that dogs were only buried where and when human diets were relatively rich in aquatic foods, which here most likely included river and lake fish and Baikal seal (Phoca sibirica). Generally, human and dog diets appear to have been similar across the study subregions, and this is important for interpreting their radiocarbon dates, and comparing them to those obtained on the region’s human remains, both of which likely carry a freshwater old carbon bias. Slight offsets were observed in the isotope values of dogs and humans in our samples, particularly where both have diets rich in aquatic fauna. This may result from dietary differences between people and their dogs, perhaps due to consuming fish of different sizes, or even different tissues from the same aquatic fauna. This paper also provides a first glimpse of the DNA of ancient canids in Northeast Asia. PMID:23696851

Validation of Alternatives to Aliphatic Isocyanate Polyurethanes

NASA Technical Reports Server (NTRS)

Curran, Jerome

2007-01-01

The National Aeronautics and Space Administration (NASA) Headquarters chartered the Acquisition Pollution Prevention (AP2) Office to coordinate agency activities affecting pollution prevention issues identified during system and component acquisition and sustainment processes. The primary objective of this effort is to demonstrate and validate alternatives to aliphatic isocyanate polyurethane coatings. Successful completion of this project will result in one or more isocyanate-free coating systems qualified for use at Air Force Space Command (AFSPC) and NASA centers participating in this study. The objective of this project is to qualify the candidates under the specifications for the standard system. This project will compare coating performance of the proposed alternatives to existing coating systems or standards.

Colorimetric qualification of shear sensitive liquid crystal coatings

NASA Technical Reports Server (NTRS)

Muratore, Joseph J., Jr.

1993-01-01

The work that has been done to date on the Shear Sensitive Liquid Crystal Project demonstrated that cholesteric liquid crystal coatings respond to both the direction and magnitude of a shearing force. The response of the coating is to selectively scatter incident white light into a spectrum of colors. Discernible color changes at a fixed angle of observation and illumination are the result of an applied shear stress. The intention was to be able to convert these observable color patterns from a flow visualization technique into a quantitative tool. One of the earlier intentions was to be able to use liquid crystals in dynamic flow fields. This was assumed possible because liquid crystals had made it possible to visualize transients in surface shear forces. Although the transients were visualized by color changes to an order one micro second, the time response of a coating to align to a shearing force is dependent on the magnitude of the change between its initial and final states. Unfortunately, the response is not instantaneous. It is for this reason any future attempt at quantifying the magnitude and directions of a shearing force are limited to surface shear stress vector fields in three dimensional steady state flows. This limitation does not significantly detract from the utility of liquid crystal coatings. The measurement of skin friction in the study of transition on wings, prediction of drag forces, performance assessment, and the investigation of boundary layer behavior is of great importance in aerodynamics. There exist numerous examples of techniques for the measurement of surface shear stress. Most techniques require arduous calibrations and necessitate extensive preparation of the receiving surfaces. However, the main draw back of instruments such as Preston tubes, hot films, buried wire gages, and floating element balances is that they only provide a point measurement. The advantages of capturing global shear data would be appreciable when compared with conventional point measurement sensors. It has yet to be determined if a repeatable correlation exists between the measured color of a liquid crystal coating and the magnitude/directional components of a shear vector imposed onto it.

Field Evaluations Test Plan for Validation of Alternatives to Aliphatic Isocyanate Polyurethanes

NASA Technical Reports Server (NTRS)

Lewis, Pattie

2005-01-01

The objective of this project is to qualify candidate alternatives to Aliphatic Isocyanate Polyurethane coatings under the specifications for the standard system. This project will compare coating performance of the proposed alternatives to existing coating systems or standards.

Effect of Adhesive Strips and Dermal Sutures vs Dermal Sutures Only on Wound Closure

PubMed Central

Custis, Trenton; Armstrong, April W.; King, Thomas H.; Sharon, Victoria R.; Eisen, Daniel B.

2016-01-01

IMPORTANCE Although applying adhesive strips to a wound closure has been shown to have outcomes equivalent to those with cuticular suturing, it is unknown whether adhesive strips provide additional benefit compared with dermal suturing alone. OBJECTIVE To determine whether the addition of adhesive strips to a wound closed with buried interrupted subcuticular sutures improves outcomes following wound closure. DESIGN, SETTING, AND PARTICIPANTS A prospective, randomized split-wound intervention was conducted between November 14, 2013, and May 16, 2014, in patients who underwent cutaneous surgical procedures at the University of California, Davis, outpatient dermatology clinic. Fifty-seven patients 18 years or older with postoperative defects of at least 3 cm, resulting from either Mohs micrographic surgical procedures or surgical excision, were screened for participation. Nine patients were excluded and 48 were enrolled. INTERVENTIONS Half of each wound was randomized to receive buried interrupted subcuticular sutures and overlying adhesive strips and the other half received buried interrupted subcuticular sutures only. MAIN OUTCOMES AND MEASURES At 3 months’ follow-up, each patient and 2 blinded observers evaluated the wound using the Patient Observer Scar Assessment Scale. RESULTS The total mean (SD) Patient Observer Scar Assessment Scale score for observers for the side that received a combination of adhesive strips and buried interrupted subcuticular suturing (12.3 [4.8]) and the side that received sutures only (12.9 [6.3]) did not differ significantly at 3 months (P = .32). There was no significant difference in the total patient assessment scale score between the combination closure (14.0 [7.6]) and sutures only (14.7 [7.6]) sides at 3 months (P = .39). There was also no significant difference between the 2 closure methods in terms of mean (SD) scar width (both methods: 1.1 [0.8] mm, P = .89) at follow-up. CONCLUSIONS AND RELEVANCE Combination closure with adhesive strips and buried interrupted subcuticular suturing was not significantly associated with improved overall scar assessment compared with buried interrupted subcuticular suturing alone when evaluated by blinded observers or the patients themselves. Our results do not support the use of adhesive strips as a means to improve cosmetic outcomes or reduce scar width. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01979497 PMID:25875131

An Efficient Covalent Coating on Glass Slides for Preparation of Optical Oligonucleotide Microarrays

PubMed Central

Pourjahed, Atefeh; Rabiee, Mohammad; Tahriri, Mohammadreza

2013-01-01

Objective(s): Microarrays are potential analyzing tools for genomics and proteomics researches, which is in needed of suitable substrate for coating and also hybridization of biomolecules. Materials and Methods: In this research, a thin film of oxidized agarose was prepared on the glass slides which previously coated with poly-L-lysine (PLL). Some of the aldehyde groups of the activated agarose linked covalently to PLL amine groups; also bound to the amino groups of biomolecules. These linkages were fixed by UV irradiation. The prepared substrates were compared to only agarose-coated and PLL-coated slides. Results: Results on atomic force microscope (AFM) demonstrated that agarose provided three-dimensional surface which had higher loading and bindig capacity for biomolecules than PLL-coated surface which had two-dimensional surface. In addition, the signal-to-noise ratio in hybridization reactions performed on the agarose-PLL coated substrates increased two fold and four fold compared to agarose and PLL coated substrates, respectively. Conclusion: The agarose-PLL microarrays had the highest signal (2546) and lowest background signal (205) in hybridization, suggesting that the prepared slides are suitable in analyzing wide concentration range of analytes. PMID:24570832

Behavioral and pharmacological phenotypes of brain-specific diacylglycerol kinase δ-knockout mice.

PubMed

Usuki, Takako; Takato, Tamae; Lu, Qiang; Sakai, Hiromichi; Bando, Kana; Kiyonari, Hiroshi; Sakane, Fumio

2016-10-01

Diacylglycerol kinase (DGK) is a lipid-metabolizing enzyme that phosphorylates diacylglycerol to produce phosphatidic acid. Previously, we reported that the δ isozyme of DGK was abundantly expressed in the mouse brain. However, the functions of DGKδ in the brain are still unclear. Because conventional DGKδ-knockout (KO) mice die within 24h after birth, we have generated brain-specific conditional DGKδ-KO mice to circumvent the lethality. In the novel object recognition test, the number of contacts in the DGKδ-KO mice to novel and familiar objects was greatly increased compared to the control mice, indicating that the DGKδ-KO mice showed irrational contacts with objects such as compulsive checking. In the marble burying test, which is used for analyzing obsessive-compulsive disorder (OCD)-like phenotypes, the DGKδ-KO mice buried more marbles than the control mice. Additionally, these phenotypes were significantly alleviated by the administration of an OCD remedy, fluoxetine. These results indicate that the DGKδ-KO mice showed OCD-like behaviors. Moreover, the number of long axon/neurites increased in both DGKδ-KO primary cortical neurons and DGKδ-knockdown neuroblastoma Neuro-2a cells compared to control cells. Conversely, overexpression of DGKδ decreased the number of long axon/neurites of Neuro-2a cells. Taken together, these results strongly suggest that a deficiency of DGKδ induces OCD-like behavior through enhancing axon/neurite outgrowth. Copyright © 2016 Elsevier B.V. All rights reserved.

Scattering of Acoustic Waves from Ocean Boundaries

DTIC Science & Technology

2015-09-30

of buried mines and improve SONAR performance in shallow water. OBJECTIVES 1) Determination of the correct physical model of acoustic propagation... acoustic parameters in the ocean. APPROACH 1) Finite Element Modeling for Range Dependent Waveguides: Finite element modeling is applied to a...roughness measurements for reverberation modeling . GLISTEN data provide insight into the role of biology on acoustic propagation and scattering

The Objective Force Soldier/Soldier Team. Volume II - The Science and Technology Challenges

DTIC Science & Technology

2001-11-01

processing for buried mines Chemical sniffing to detect explosives • UGV/Robotic systems to carry sensors into risk areas • Specialized electronic...CLOSE COMBAT OPTIC 1.4 THERMAL WEAPONS SIGHT 4.9 AN/ PAQ -4C AIMING LIGHT 0.6 DAYLIGHT VIDEO SIGHT 0.2 IMPROVED HELMET 3.2 HELMET MOUNTED DISPLAY 1.5 w

Using evolutionary computation to optimize an SVM used in detecting buried objects in FLIR imagery

NASA Astrophysics Data System (ADS)

Paino, Alex; Popescu, Mihail; Keller, James M.; Stone, Kevin

2013-06-01

In this paper we describe an approach for optimizing the parameters of a Support Vector Machine (SVM) as part of an algorithm used to detect buried objects in forward looking infrared (FLIR) imagery captured by a camera installed on a moving vehicle. The overall algorithm consists of a spot-finding procedure (to look for potential targets) followed by the extraction of several features from the neighborhood of each spot. The features include local binary pattern (LBP) and histogram of oriented gradients (HOG) as these are good at detecting texture classes. Finally, we project and sum each hit into UTM space along with its confidence value (obtained from the SVM), producing a confidence map for ROC analysis. In this work, we use an Evolutionary Computation Algorithm (ECA) to optimize various parameters involved in the system, such as the combination of features used, parameters on the Canny edge detector, the SVM kernel, and various HOG and LBP parameters. To validate our approach, we compare results obtained from an SVM using parameters obtained through our ECA technique with those previously selected by hand through several iterations of "guess and check".

Detection of shallow buried objects using an autoregressive model on the ground penetrating radar signal

NASA Astrophysics Data System (ADS)

Nabelek, Daniel P.; Ho, K. C.

2013-06-01

The detection of shallow buried low-metal content objects using ground penetrating radar (GPR) is a challenging task. This is because these targets are right underneath the ground and the ground bounce reflection interferes with their detections. They do not create distinctive hyperbolic signatures as required by most existing GPR detection algorithms due to their special geometric shapes and low metal content. This paper proposes the use of the Autoregressive (AR) modeling method for the detection of these targets. We fit an A-scan of the GPR data to an AR model. It is found that the fitting error will be small when such a target is present and large when it is absent. The ratio of the energy in an Ascan before and after AR model fitting is used as the confidence value for detection. We also apply AR model fitting over scans and utilize the fitting residual energies over several scans to form a feature vector for improving the detections. Using the data collected from a government test site, the proposed method can improve the detection of this kind of targets by 30% compared to the pre-screener, at a false alarm rate of 0.002/m2.

Do manganese nodules grow or dissolve after burial? Results from the Central Indian Ocean Basin

NASA Astrophysics Data System (ADS)

Pattan, J. N.; Parthiban, G.

2007-07-01

Fifty buried manganese nodules at different depth intervals were recovered in 12 sediment cores from the Central Indian Ocean Basin (CIOB). A maximum of 15 buried nodules were encountered in one sediment core (AAS-22/GC-07) and the deepest nodule was recovered at 5.50 m below seafloor in core AAS-04/GC-5A. Approximately 80% of the buried nodules are small in size (˜2 cm diameter) in contrast to the Atlantic Ocean and Peru Basin (Pacific Ocean) where the majority of the buried nodules are large, ˜8 cm and >6 cm, respectively. Buried nodule size decreases with core depth and this distribution appears to be similar to the phenomenon of "Brazil Nut Effect". Buried nodules exhibit both smooth and rough surface textures and are ellipsoidal, elongated, rounded, sub rounded, irregular and polynucleated. Buried nodules from siliceous ooze are enriched in Mn, Cu, Ni, Zn, Mo, Ga, V and Rb whereas those from red clay are enriched in Fe, Co, Ti, U, Th, Y, Cr, Nb and Rare Earth Elements (REE). Buried nodules from siliceous ooze suggest their formation under hydrogenetic, early digenetic and diagenetic processes whereas those from red clay are of hydrogenetic origin. REE are enriched more than 1.5 times in buried nodules from red clay compared to siliceous ooze. However, the mode of incorporation of REE into buried nodules from both sedimentary environments is by a single authigenic phase consisting of Fe-Ti-P. Shale-normalized REE patterns and Ce anomalies suggest that nodules from siliceous ooze formed under more oxidizing conditions than those from red clay. Nodules buried at depths between 1.5 and 2.5 m are diagenetic (Mn/Fe ratio 10-15), formed in highly oxic environments (large positive Ce anomalies) and record aeolian dust (high Eu anomalies). Chemical composition, surface texture and morphology of buried nodules are similar to those of surface nodules from the same basin. Furthermore, buried nodule compositions do not exhibit any distinct patterns within the core depth, suggesting that buried nodules neither grow nor dissolve after their burial in the sediment column.

Buried transuranic wastes at ORNL: Review of past estimates and reconciliation with current data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trabalka, J.R.

1997-09-01

Inventories of buried (generally meaning disposed of) transuranic (TRU) wastes at Oak Ridge National Laboratory (ORNL) have been estimated for site remediation and waste management planning over a period of about two decades. Estimates were required because of inadequate waste characterization and incomplete disposal records. For a variety of reasons, including changing definitions of TRU wastes, differing objectives for the estimates, and poor historical data, the published results have sometimes been in conflict. The purpose of this review was (1) to attempt to explain both the rationale for and differences among the various estimates, and (2) to update the estimatesmore » based on more recent information obtained from waste characterization and from evaluations of ORNL waste data bases and historical records. The latter included information obtained from an expert panel`s review and reconciliation of inconsistencies in data identified during preparation of the ORNL input for the third revision of the Baseline Inventory Report for the Waste Isolation Pilot Plant. The results summarize current understanding of the relationship between past estimates of buried TRU wastes and provide the most up-to-date information on recorded burials thereafter. The limitations of available information on the latter and thus the need for improved waste characterization are highlighted.« less

Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces

NASA Technical Reports Server (NTRS)

Dussinger, Peter M.; Lindemuth, James E.

1997-01-01

The principal objective of this Phase 2 SBIR program was to develop and demonstrate a practically insoluble coating for nickel-based superalloys for Stirling engine heat pipe applications. Specific technical objectives of the program were: (1) Determine the solubility corrosion rates for Nickel 200, Inconel 718, and Udimet 72OLI in a simulated Stirling engine heat pipe environment, (2) Develop coating processes and techniques for capillary groove and screen wick structures, (3) Evaluate the durability and solubility corrosion rates for capillary groove and screen wick structures coated with an insoluble coating in cylindrical heat pipes operating under Stirling engine conditions, and (4) Design and fabricate a coated full-scale, partial segment of the current Stirling engine heat pipe for the Stirling Space Power Convertor program. The work effort successfully demonstrated a two-step nickel aluminide coating process for groove wick structures and interior wall surfaces in contact with liquid metals; demonstrated a one-step nickel aluminide coating process for nickel screen wick structures; and developed and demonstrated a two-step aluminum-to-nickel aluminide coating process for nickel screen wick structures. In addition, the full-scale, partial segment was fabricated and the interior surfaces and wick structures were coated. The heat pipe was charged with sodium, processed, and scheduled to be life tested for up to ten years as a Phase 3 effort.

Evaluation of Erosion Resistance of Advanced Turbine Thermal Barrier Coatings

NASA Technical Reports Server (NTRS)

Zhu, Dongming; Kuczmarski, Maria A.; Miller, Robert A.; Cuy, Michael D.

2007-01-01

The erosion resistant turbine thermal barrier coating system is critical to aircraft engine performance and durability. By demonstrating advanced turbine material testing capabilities, we will be able to facilitate the critical turbine coating and subcomponent development and help establish advanced erosion-resistant turbine airfoil thermal barrier coatings design tools. The objective of this work is to determine erosion resistance of advanced thermal barrier coating systems under simulated engine erosion and/or thermal gradient environments, validating advanced turbine airfoil thermal barrier coating systems based on nano-tetragonal phase toughening design approaches.

Retrieval of Shape Characteristics for Buried Objects with GPR Monitoring

NASA Astrophysics Data System (ADS)

Soldovieri, F.; Comite, D.; Galli, A.; Valerio, G.; Barone, P. M.; Lauro, S. E.; Mattei, E.; Pettinelli, E.

2012-04-01

Information retrieval on the location and the geometrical features (dimensions and shape) of buried objects is of fundamental importance in geosciences areas involving environmental protection, mine clearance, archaeological investigations, space and planetary exploration, and so forth. Among the different non-invasive sensing techniques usually employed to achieve this kind of information, those based on ground-penetrating-radar (GPR) instruments are well-established and suitable to the mentioned purposes [1]. In this context, our interest in the present work is specifically focused on testing the potential performance of typical GPR instruments by means of appropriate data processing. It will be shown in particular to what extent the use of a suitable "microwave tomographic approach" [2] is able to furnish a shape estimation of the targets, possibly recognizing different kinds of canonical geometries, even having reduced cross sections and in critical conditions, where the scatterer size is comparable with resolution limits imposed by the usual measurement configurations. Our study starts by obtaining the typical "direct" information from the GPR techniques that is the scattered field in subsurface environments under the form of radargrams. In order to get a wide variety of scenarios for the operating conditions, this goal is achieved by means of two different and independent approaches [3]. One approach is based on direct measurements through an experimental laboratory setup: commercial GPR instruments (typically bistatic configurations operating around 1 GHz frequency range) are used to collect radargram profiles by investigating an artificial basin filled of liquid and/or granular materials (sand, etc.), in which targets (having different constitutive parameters, shape, and dimensions) can be buried. The other approach is based on numerical GPR simulations by means of a commercial CAD electromagnetic tool (CST), whose suitable implementation and data processing allow us to retrieve results again in the form of radargrams for the scattering features of arbitrarily-composed subsurfaces. Once these types of "direct" (measured and/or simulated) radargram data are obtained, the "inverse" problem is then handled, based on a Born approximation to linearize the scattering problem. The targets are represented in terms of anomalies ("contrast function") of dielectric permittivity and conductivity with respect to the properties of a background environment. The analysis of the relevant results for the spatial distribution of the magnitude of the contrast function shows that, in various even-challenging practical cases, this kind of approach is able to properly locate buried objects, also identifying the relevant shape features. [1] D. J. Daniels (Ed.), Ground penetrating radar. IEE Press, 2004. [2] E. Pettinelli, A. Di Matteo, E. Mattei, L. Crocco, F. Soldovieri, J. D. Redman, and A. P. Annan, "GPR response from buried pipes: measurement on field site and tomographic reconstructions," IEEE Trans. Geosci. Remote Sensing, vol. 47, pp. 2639-2645, Aug. 2009. [3] G. Valerio, A. Galli, P. M. Barone, S. E. Lauro, E. Mattei, and E. Pettinelli, "GPR detectability of rocks in a Martian-like shallow subsoil: a numerical approach," Planet. Space Sci., 10 pp., doi: 10.1016/j.pss.2011.12.003, 2011.

Surface Finish Effects Using Coating Method on 3D Printing (FDM) Parts

NASA Astrophysics Data System (ADS)

Haidiezul, AHM; Aiman, AF; Bakar, B.

2018-03-01

One of three-dimensional (3-D) printing economical processes is by using Fused Deposition Modelling (FDM). The 3-D printed object was built using layer-by-layer approach which caused “stair stepping” effects. This situation leads to uneven surface finish which mostly affect the objects appearance for product designers in presenting their models or prototypes. The objective of this paper is to examine the surface finish effects from the application of XTC-3D coating developed by Smooth-On, USA on the 3D printed parts. From the experimental works, this study shows the application of XTC-3D coating to the 3-D printed parts has improve the surface finish by reducing the gap between the layer

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

49 CFR 193.2629 - External corrosion control: buried or submerged components.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

NASA and ESA Collaboration on Hexavalent Chrome Alternatives Pretreatments Only Interim Test Report

NASA Technical Reports Server (NTRS)

Kessel, Kurt R.

2015-01-01

NASA and ESA continue to search for an alternative to hexavalent chromium in coatings applications that meet their performance requirements in corrosion protection, cost, operability, and health and safety, while typically specifying that performance must be equal to or greater than existing systems. The overall objective of the collaborative effort between NASA TEERM and ESA is to test and evaluate coating systems (pretreatments, pretreatments with primer, and pretreatments with primer and topcoat) as replacements for hexavalent chrome coatings in aerospace applications. This objective will be accomplished by testing promising coatings identified from previous NASA, ESA, Department of Defense (DOD), and other project experience. Additionally, several new materials will be analyzed according to ESA-identified specifications.

Neuronal nicotinic receptor antagonist reduces anxiety-like behavior in mice.

PubMed

Roni, Monzurul Amin; Rahman, Shafiqur

2011-10-31

Brain cholinergic neurotransmission has been implicated in the modulation of anxiety in humans and evidence suggests that drugs targeting neuronal nicotinic acetylcholine receptor (nAChR) could have potential for the treatment of anxiety. The objective of present study was to examine anxiolytic effects of lobeline (0.04 or 0.1 mg/kg), a nAChR antagonist, in C57BL/6J mice using elevated plus-maze (EPM) and marble-burying test. Lobeline (0.04 mg/kg) significantly increased open arm time on EPM and reduced number of marbles buried. Similarly, mecamylamine (0.3 mg/kg) produced anxiolytic effects, while peripherally acting hexamethonium (0.3 mg/kg) failed to produce any response. These results provide evidence that lobeline has anxiolytic potential and nAChR antagonists may represent a new class of anxiolytics in humans. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Development of Multilayer Coatings for Hard X-Ray Optics at NASA Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

Gurgew, Danielle N.; Broadway, David M.; Ramsey, Brian; Gregory, Don

2017-01-01

Broadband X-ray multilayer coatings are under development at NASA MSFC for use on future astronomical X-ray telescopes. Multilayer coatings deposited onto the reflecting surfaces of X-ray optics can provide a large bandpass enabling observations of higher energy astrophysical objects and phenomena.

PAINT ADHESION AND CORROSION PERFORMANCE OF CHROMIUM-FREE PRETREATMENTS OF 55% AL-ZN-COATED STEEL

EPA Science Inventory

The adhesion and corrosion performances for several pretreatments of 55% Al-Zn-coated steels which were coil-coated with polyester paint systems were determined. The objective of this study was to evaluate new, silane-based metal pretreatments and to compare their performance wit...

Sexual and Overall Quality of Life Improvements After Surgical Correction of "Buried Penis".

PubMed

Hughes, Duncan B; Perez, Edgar; Garcia, Ryan M; Aragón, Oriana R; Erdmann, Detlev

2016-05-01

"Buried penis" is an increasing burden in our population with many possible etiologies. Although surgical correction of buried penis can be rewarding and successful for the surgeon, the psychological and functional impact of buried penis on the patient is less understood. The study's aim was to evaluate the sexual satisfaction and overall quality of life before and after buried penis surgery in a single-surgeon's patient population using a validated questionnaire (Changes in Sexual Functioning Questionnaire short-form). Using Likert scales generated from the questionnaire and 1-tailed paired t test analysis, we found that there was significantly improved sexual function after correction of a buried penis. Variables individually showed that there was significant improvement with sexual pleasure, urinating, and with genital hygiene postoperatively. There were no significant differences concerning frequency of pain with orgasms. Surgical correction of buried penis significantly improves the functional, sexual, and psychological aspects of patient's lives.

Instability of buried hydration sites increases protein subdomains fluctuations in the human prion protein by the pathogenic mutation T188R

NASA Astrophysics Data System (ADS)

Tomobe, Katsufumi; Yamamoto, Eiji; Akimoto, Takuma; Yasui, Masato; Yasuoka, Kenji

2016-05-01

The conformational change from the cellular prion protein (PrPc) to scrapie prion protein (PrPsc) is a key process in prion diseases. The prion protein has buried water molecules which significantly contribute to the stability of the protein; however, there has been no report investigating the influence on the buried hydration sites by a pathogenic mutation not adjacent to the buried hydration sites. Here, we perform molecular dynamics simulations of wild type (WT) PrPc and pathogenic point mutant T188R to investigate conformational changes and the buried hydration sites. In WT-PrPc, four buried hydration sites are identified by residence time and rotational relaxation analysis. However, there are no stable buried hydration sites in one of T188R simulations, which indicates that T188R sometimes makes the buried hydration sites fragile. We also find that fluctuations of subdomains S1-H1-S2 and H1-H2 increase in T188R when the buried hydration sites become unstable. Since the side chain of arginine which is replaced from threonine in T188R is larger than of threonine, the side chain cannot be embedded in the protein, which is one of the causes of the instability of subdomains. These results show correlations between the buried hydration sites and the mutation which is far from them, and provide a possible explanation for the instability by mutation.

Laboratory investigation of fire protection coatings for creosote-treated timber railroad bridges

Treesearch

Carol A. Clausen; Robert H. White; James P. Wacker; Stan T. Lebow; Mark A. Dietenberger; Samuel L. Zelinka; Nicole M. Stark

2014-01-01

As the incidence of timber railroad bridge fires increases, so has the need to develop protective measures to reduce the risk from accidental ignitions primarily caused by hot metal objects. Of the six barrier treatments evaluated in the laboratory for their ability to protect timbers from fires sourced with ignition from hot metal objects only one intumescent coating...

A Novel Nonelectrolytic Process for Chromium and Nickel Coating

DTIC Science & Technology

2015-06-01

thermal spraying and involves similar protocols for coating an object. The process proceeds after powder is injected into a plasma jet then superheated...HVOF) High velocity oxygen fuel coating is characteristic of a thermal spray coating process , enhancing anti-corrosion and anti-wear properties of...observations due to limited metal deposition on the surface during treatment. No powder particles were produced during this RES process . a. Optical

Protective matching polymer powder coating of piezoelectric element

NASA Astrophysics Data System (ADS)

Gavrilova, V. A.; Fazlyyyakhmatov, M. G.; Kashapov, N. F.

2013-12-01

Objects of research are coatings and technology of their applying to the piezoelectric elements for ultrasound. Acoustic impedance and thicknesses of matching layers for medical ultrasound transducers have been defined. In this paper performance characteristics of coating systems with predetermined properties have been selected. The conditions for selection of polymer powder paint for quarter wave matching layer have been determined. Conditions of forming polymer powder coatings have been proposed.

Full wave two-dimensional modeling of scattering and inverse scattering for layered rough surfaces with buried objects

NASA Astrophysics Data System (ADS)

Kuo, Chih-Hao

Efficient and accurate modeling of electromagnetic scattering from layered rough surfaces with buried objects finds applications ranging from detection of landmines to remote sensing of subsurface soil moisture. The formulation of a hybrid numerical/analytical solution to electromagnetic scattering from layered rough surfaces is first presented in this dissertation. The solution to scattering from each rough interface is sought independently based on the extended boundary condition method (EBCM), where the scattered fields of each rough interface are expressed as a summation of plane waves and then cast into reflection/transmission matrices. To account for interactions between multiple rough boundaries, the scattering matrix method (SMM) is applied to recursively cascade reflection and transmission matrices of each rough interface and obtain the composite reflection matrix from the overall scattering medium. The validation of this method against the Method of Moments (MoM) and Small Perturbation Method (SPM) is addressed and the numerical results which investigate the potential of low frequency radar systems in estimating deep soil moisture are presented. Computational efficiency of the proposed method is also discussed. In order to demonstrate the capability of this method in modeling coherent multiple scattering phenomena, the proposed method has been employed to analyze backscattering enhancement and satellite peaks due to surface plasmon waves from layered rough surfaces. Numerical results which show the appearance of enhanced backscattered peaks and satellite peaks are presented. Following the development of the EBCM/SMM technique, a technique which incorporates a buried object in layered rough surfaces by employing the T-matrix method and the cylindrical-to-spatial harmonics transformation is proposed. Validation and numerical results are provided. Finally, a multi-frequency polarimetric inversion algorithm for the retrieval of subsurface soil properties using VHF/UHF band radar measurements is devised. The top soil dielectric constant is first determined using an L-band inversion algorithm. For the retrieval of subsurface properties, a time-domain inversion technique is employed together with a parameter optimization for the pulse shape of time delay echoes from VHF/UHF band radar observations. Numerical studies to investigate the accuracy of the proposed inversion technique in presence of errors are addressed.

Buried topography of Utopia, Mars - Persistence of a giant impact depression

NASA Technical Reports Server (NTRS)

Mcgill, George E.

1989-01-01

Knobs, partially buried craters, ring fractures, and some mesas permit a qualitative determination of the topography buried beneath younger northern plains materials. These features are widely distributed in the Utopia area but are absent in a large, roughly circular region centered at about 48 deg N, 240 deg W. This implies the existence of a circular depression about 3300 km in diameter buried beneath Utopia Planitia that is interpreted to represent the central part of a very large impact basin. The presence of buried curved massifs around part of this depression, and a roughly coincident mascon, lend further support. Present topography, areal geology, and paleotopography of buried surfaces all point to the persistence of this major depression for almost the entire history of Mars.

Magnetic Gradient Horizontal Operator (MHGO) useful for detecting objects buried at shallow depth: cultural heritage (Villa degli Antonini, Rota Rio)

NASA Astrophysics Data System (ADS)

Di Filippo, Michele; Di Nezza, Maria

2016-04-01

Several factors were taken into consideration in order to appropriately tailor the geophysical explorations at the cultural heritage. Given the fact that each site has been neglected for a long time and in recent times used as an illegal dumping area, we thoroughly evaluated for this investigation the advantages and limitations of each specific technique, and the general conditions and history of the site. We took into account the extension of the areas to be investigated and the need for rapid data acquisition and processing. Furthermore, the survey required instrumentation with sensitivity to small background contrasts and as little as possible affected by background noise sources. In order to ascertain the existence and location of underground buried walls, a magnetic gradiometer survey (MAG) was planned. The map of the magnetic anomalies is not computed to reduction at the pole (RTP), but with a magnetic horizontal gradient operator (MHGO). The magnetic horizontal gradient operator (MHGO) generates from a grid of vertical gradient a grid of steepest slopes (i.e. the magnitude of the gradient) at any point on the surface. The MHGO is reported as a number (rise over run) rather than degrees, and the direction is opposite to that of the slope. The MHGO is zero for a horizontal surface, and approaches infinity as the slope approaches the vertical. The gradient data are especially useful for detecting objects buried at shallow depth. The map reveals some details of the anomalies of the geomagnetic field. Magnetic anomalies due to walls are more evident than in the total intensity map, whereas anomalies due to concentrations of debris are very weak. In this work we describe the results of an investigation obtained with magnetometry investigation for two archaeological sites: "Villa degli Antonini" (Genzano, Rome) and Rota Ria (Mugnano in Teverina, Viterbo). Since the main goal of the investigation was to understand the nature of magnetic anomalies with cost-effective method, we have also detection and location of underground buried structures using different instruments and techniques geophysical were carried out (EMI, GPR and microgravity) and so far excavated only in a targeted sector of the area of the anomaly labeled in order to test the validity of the geophysical survey.

Subsurface characterization by the ground penetrating radar WISDOM/ExoMars 2020

NASA Astrophysics Data System (ADS)

Hervé, Y.; Ciarletti, V.; Le Gall, A. A.; Oudart, N.; Loizeau, D.; Guiffaut, C.; Dorizon, S.

2017-12-01

The main objective of the ExoMars 2020 mission is to search for signs of past and/or present life on Mars. Toward this goal, a rover was designed to investigate the shallow subsurface which is the most likely place where signs of life may be preserved, beneath the hostile surface of Mars. The rover of the ExoMars 2020 mission has on board a polarimetric ground penetrating radar called WISDOM (Water Ice Subsurface Deposits Observation on Mars). Thanks to its large frequency bandwidth of 2.5 GHz, WISDOM is able to probe down to a depth of approximately 3 m on sedimentary rock with a vertical resolution of a few centimeters.The main scientific objectives of WISDOM are to characterize the shallow subsurface of Mars, to help understand the local geological context and to identify the most promising location for drilling. The WISDOM team is currently working on the preparation of the scientific return of the ExoMars 2020 mission. In particular, tools are developed to interpret WISDOM experimental data and, more specifically, to extract information from the radar signatures of expected buried reflectors. Insights into the composition of the ground (through the retrieval of its permittivity) and the geological context of the site can be inferred from the radar signature of buried rocks since the shape and the density of rocks in the subsurface is related to the geological processes that have shaped and placed them there (impact, fluvial processes, volcanism). This paper presents results obtained by automatic detection of structures of interest on a radargram, especially radar signature of buried rocks. The algorithm we developed uses a neural network to identify the position of buried rocks/blocs and then a Hough transform to characterize each signature and to estimate the local permittivity of the medium. Firstly, we will test the performances of the algorithm on simulated data constructed with a 3D FDTD code. This code allows us to simulate radar operation in realistic environments. Secondly, we will test our algorithm on experimental data acquired in a semi-controlled environment. Lastly, we will present experimental data acquired during a recent field campaign (July 2017) in the south of France and we will validate our method and illustrate the ability of WISDOM to provide clues about the geological context of a site.

Selection of Optical Cavity Surface Coatings for 1micron Laser Based Missions

NASA Technical Reports Server (NTRS)

Hedgeland, Randy J.; Straka, Sharon; Matsumura, Mark; Hammerbacher, Joseph

2004-01-01

The particulate surface cleanliness level on several coatings for aluminum and beryllium substrates were examined for use in the optical cavities of high pulse energy Nd:YAG Q-switched, diode-pumped lasers for space flight applications. Because of the high intensity of the lasers, any contaminants in the laser beam path could damage optical coatings and limit the instrument mission objectives at the operating wavelength of 1 micron (micrometer). Our goal was to achieve an EST-STD-CC1246D Level 100 particulate distribution or better to ensure particulate redistribution during launch would not adversely affect the performance objectives. Tapelifts were performed to quantify the amount of particles using in-house developed procedures. The primary candidate coatings included chromate conversion coating aluminum (Al), uncoated Al electroless Nickel (Ni) on Al, Ni-gold (Au) on Al, anodized Al, and gold (Au)/Ni on Beryllium (Be). The results indicate that there were advantages in Ni and Au coating applications for the two major substrates, Al and Be, when considering applications that need to meet launch environments.

The effects of hydrogen embrittlement by cathodic protection on the CTOD of buried natural gas pipeline

NASA Astrophysics Data System (ADS)

Kim, Cheol-man; Kim, Woo-sik; Kho, Young-tai

2002-04-01

For the corrosion protection of natural gas transmission pipelines, two methods are used, cathodic protection and a coating technique. In the case of cathodic protection, defects are embrittled by hydrogen occurring at crack tips or surfaces of materials. It is, however, very important to evaluate whether cracks in the embrittled area can grow or not, especially in weld metal. In this work, on the basis of elastic plastic fracture mechanics, we performed CTOD testing under various test conditions, such as potential and current density. The CTOD of the base steel and weld metal showed a strong dependence on the test conditions. The CTOD decreased with increasing cathodic potential and current density. The morphology of the fracture surface showed quasi-cleavage. Cathodic overprotection results in hydrogen embrittlement at the crack tip.

Building America Case Study: Compact Buried Ducts in a Hot-Humid Climate House, Lady's Island, South Carolina

DOE Office of Scientific and Technical Information (OSTI.GOV)

2016-02-01

A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely onmore » encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences, 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs, and 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.« less

Compact Buried Ducts in a Hot-Humid Climate House

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mallay, Dave

2016-01-07

"9A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely onmore » encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences; 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs; 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.« less

Numerical Modeling of Mechanical Behavior for Buried Steel Pipelines Crossing Subsidence Strata

PubMed Central

Han, C. J.

2015-01-01

This paper addresses the mechanical behavior of buried steel pipeline crossing subsidence strata. The investigation is based on numerical simulation of the nonlinear response of the pipeline-soil system through finite element method, considering large strain and displacement, inelastic material behavior of buried pipeline and the surrounding soil, as well as contact and friction on the pipeline-soil interface. Effects of key parameters on the mechanical behavior of buried pipeline were investigated, such as strata subsidence, diameter-thickness ratio, buried depth, internal pressure, friction coefficient and soil properties. The results show that the maximum strain appears on the outer transition subsidence section of the pipeline, and its cross section is concave shaped. With the increasing of strata subsidence and diameter-thickness ratio, the out of roundness, longitudinal strain and equivalent plastic strain increase gradually. With the buried depth increasing, the deflection, out of roundness and strain of the pipeline decrease. Internal pressure and friction coefficient have little effect on the deflection of buried pipeline. Out of roundness is reduced and the strain is increased gradually with the increasing of internal pressure. The physical properties of soil have a great influence on the mechanical properties of buried pipeline. The results from the present study can be used for the development of optimization design and preventive maintenance for buried steel pipelines. PMID:26103460

Buried Oxide Densification for Low Power, Low Voltage CMOS Applications

NASA Technical Reports Server (NTRS)

Allen, L. P.; Anc, M. J.; Dolan, B.; Jiao, J.; Guss, B.; Seraphin, S.; Liu, S. T.; Jenkins, W.

1998-01-01

Special technology and circuit architecture are of growing interest for implementation of circuits which operate at low supply voltages and consume low power levels without sacrificing performance[1]. Use of thin buried oxide SOI substrates is a primary approach to simultaneously achieve these goals. A significant aspect regarding SIMOX SOI for low voltage, low power applications is the reliability and performance of the thin buried oxide. In addition, when subjected to high total dose irradiation, the silicon islands within the BOX layer of SIMOX can store charges and significantly effect the back channel threshold voltages of devices. Thus, elimination of the islands within the buried oxide (BOX) layer is preferred in order to prevent leakage through these conductive islands and charge build-up within the buried oxide layer. A differential (2-step) ramp rate as applied to full and 100 nm BOX SIMOX was previously reported to play a significant role in the stoichiometry and island formation within the buried layer[2]. This paper focus is on the properties of a thin (120nm) buried oxide as a function of the anneal ramp rate and the temperature of anneal. In this research, we have found an improvement in the buried oxide stoichiometry with the use of a slower, singular ramp rate for specified thin buried oxides, with slower ramp rates and higher temperatures of anneal suggested for reducing the presence of Si islands within the BOX layer.

Buried aquifers in the Brooten-Belgrade and Lake Emily areas, west-central Minnesota--Factors related to developing water for irrigation

USGS Publications Warehouse

Wolf, R.J.

1976-01-01

Potential water problems include slow rate of recharge to buried aquifers, and head loss caused by screening of the surficial and buried aquifers in the same well, and by allowing well to flow unabated. Another potential problem is possible pollution of the buried aquifers through the boreholes of multiaquifer wells.

The Effectiveness of a NiCrY-Coating on a Powder Metallurgy Disk Superalloy

NASA Technical Reports Server (NTRS)

Gabb, Timothy P.; Miller, Robert A.; Nesbitt, James A.; Draper, Susan L.; Rogers, Richard B.; Telesman, Jack

2018-01-01

Protective ductile coatings could be necessary to mitigate oxidation and corrosion attack on superalloy disks in some turbine engine applications. However, the effects of coatings on fatigue life of the disk during service are an important concern. The objective of this study was to investigate how such a coating could perform after varied post-coating processing. Cylindrical gage fatigue specimens of powder metallurgy-processed disk superalloy LSHR were coated with a NiCrY coating, shot peened, preparation treated, exposed, and then subjected to fatigue at high temperature. The effects of varied shot peening, preparation treatment, and exposures on fatigue life with and without the coating were compared. Each of these variables and several of their interactions significantly influenced fatigue life.

Microfluidic Controlled Conformal Coating of Particles

NASA Astrophysics Data System (ADS)

Tsai, Scott; Wexler, Jason; Wan, Jiandi; Stone, Howard

2011-11-01

Coating flows are an important class of fluid mechanics problems. Typically a substrate is coated with a moving continuous film, but it is also possible to consider coating of discrete objects. In particular, in applications involving coating of particles that are useful in drug delivery, the coatings act as drug-carrying vehicles, while in cell therapy a thin polymeric coating is required to protect the cells from the host's immune system. Although many functional capabilities have been developed for lab-on-a-chip devices, a technique for coating has not been demonstrated. We present a microfluidic platform developed to coat micron-size spheres with a thin aqueous layer by magnetically pulling the particles from the aqueous phase to the non-aqueous phase in a co-flow. Coating thickness can be adjusted by the average fluid speed and the number of beads encapsulated inside a single coat is tuned by the ratio of magnetic to interfacial forces acting on the beads.

Nondestructive evaluation of protective coatings for the conservation of industrial monuments

NASA Astrophysics Data System (ADS)

Welp, Hubert; Lenz, Marcel; Mazzon, Cristian; Dillmann, Christopher; Gerhardt, Nils C.; Prange, Michael; Hofmann, Martin R.

2017-07-01

For the conservation of cultural monuments standard anti-corrosion coatings are not applicable because the historical character of the objects would be lost. Alternative transparent coatings have to be evaluated and monitored nondestructively with respect to their effectiveness in protecting metal surfaces. We demonstrate that Optical Coherence Tomography (OCT) can be an alternative to the currently used method of Electrochemical Impedance Spectroscopy (EIS) for the characterization of coating defects and corrosion processes.

Shallow Water Imaging Sonar System for Environmental Surveying Final Report CRADA No. TC-1130-95

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ng, L. C.; Rosenbaum, H.

The scope of this research is to develop a shallow water sonar system designed to detect and map the location of objects such as hazardous wastes or discarded ordnance in coastal waters. The system will use high frequency wide-bandwidth imaging sonar, mounted on a moving platform towed behind a boat, to detect and identify objects on the sea bottom. Resolved images can be obtained even if the targets are buried in an overlayer of silt. Reference 1 ( also attached) summarized the statement of work and the scope of collaboration.

Aeromagnetic investigations of hazardous waste sites

USGS Publications Warehouse

,

1995-01-01

Aeromagnetic survey data collected by helicopter over hazardous waste sites can be used to map the distribution of buried metallic (ferrous) objects at these sites, including drums and scrap metal. Thorough knowledge of the locations and nature of hazardous waste containers and contaminated objects is needed prior to the start of remediation efforts. Non-invasive geophysical techniques such as the aeromagnetic method provide the best way to obtain this knowledge. The U.S. Geological Survey (USGS) not only has experience in processing and interpreting aeromagnetic surveys of this type but also offers aid in the design and monitoring of contracts for such surveys.

Industrial surface coatings: Wood furniture and fixtures emission inventory development. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anex, R.P.; Lund, J.R.; Chang, D.P.Y.

1998-06-01

The purpose of this study is to update the methods for estimating emissions from the industrial coatings subcategory of wood furniture and fixtures. The wood furniture and fixture industry encompasses the manufacture of diverse products including cabinets, office furniture, store fixtures, and residential furniture. Specific objectives of this work are to: (1) estimate the amount of coating used in the industrial surface coating of wood furniture and fixtures; (2) develop emissions factors for each coating application category; (3) estimate variability of both coating use and emission factors; and (4) specify a source of information and method to revise and updatemore » the industrial coating of wood furniture and fixtures emission inventory.« less

SERS-fluorescence joint spectral encoded magnetic nanoprobes for multiplex cancer cell separation.

PubMed

Wang, Zhuyuan; Zong, Shenfei; Chen, Hui; Wang, Chunlei; Xu, Shuhong; Cui, Yiping

2014-11-01

A new kind of cancer cell separation method is demonstrated, using surface-enhanced Raman scattering (SERS) and fluorescence dual-encoded magnetic nanoprobes. The designed nanoprobes can realize SERS-fluorescence joint spectral encoding (SFJSE) and greatly improve the multiplexing ability. The nanoprobes have four main components, that is, the magnetic core, SERS generator, fluorescent agent, and targeting antibody. These components are assembled with a multi-layered structure to form the nanoprobes. Specifically, silica-coated magnetic nanobeads (MBs) are used as the inner core. Au core-Ag shell nanorods (Au@Ag NRs) are employed as the SERS generators and attached on the silica-coated MBs. After burying these Au@Ag NRs with another silica layer, CdTe quantum dots (QDs), that is, the fluorescent agent, are anchored onto the silica layer. Finally, antibodies are covalently linked to CdTe QDs. SFJSE is fulfilled by using different Raman molecules and QDs with different emission wavelengths. By utilizing four human cancer cell lines and one normal cell line as the model cells, the nanoprobes can specifically and simultaneously separate target cancer cells from the normal ones. This SFJSE-based method greatly facilitates the multiplex, rapid, and accurate cancer cell separation, and has a prosperous potential in high-throughput analysis and cancer diagnosis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Infiltration pattern in a regolith-fractured bedrock profile: field observation of a dye stain pattern

NASA Astrophysics Data System (ADS)

Kim, Jae Gon; Lee, Gyoo Ho; Lee, Jin-Soo; Chon, Chul-Min; Kim, Tack Hyun; Ha, Kyoochul

2006-02-01

We examined the infiltration pattern of water in a regolith-bedrock profile consisting of two overburdens (OB1 and OB2), a buried rice paddy soil (PS), two texturally distinctive weathered materials (WM1 and WM2) and a fractured sedimentary rock (BR), using a Brilliant Blue FCF dye tracer. A black-coloured coating in conducting fractures in WM1, WM2 and BR was analysed by X-ray diffraction and scanning electron microscopy. The dye tracer penetrated to greater than 2 m depth in the profile. The macropore flow and saturated interflow were the major infiltration patterns in the profile. Macropore flow and saturated interflow were observed along fractures in WM1, WM2 and BR and at the dipping interfaces of PS-WM1, PS-WM2 and PS-BR respectively. Heterogeneous matrix flow occurred in upper overburden (OB1) and PS. Compared with OB1, the coarser textured OB2 acted as a physical barrier for vertical flow of water. The PS with low bulk density and many fine roots was another major conducting route of water in the profile. Manganese oxide and iron oxide were positively identified in the black coating material and had low crystallinity and high surface area, indicating their high reactivity with conducting contaminants.

Evaluation of the effect of physical variables on in vitro release of diclofenac pellets using Box-Behnken design

PubMed Central

Enayatifard, Reza; Mahjoob, Aiding; Ebrahimi, Pouneh; Ebrahimnejad, Pedram

2015-01-01

Objective(s): A Box-Behnken design was used for evaluation of Eudragit coated diclofenac pellets. The purpose of this work was to optimize diclofenac pellets to improve the physicochemical properties using experimental design. Materials and Methods: Diclofenac was loaded onto the non-pareil beads using conventional coating pan. Film coating of pellets was done at the same pan. The effect of plasticizer level, curing temperature and curing time was determined on the release of diclofenac from pellets coated with polymethacrylates. Results: Increasing the plasticizer in the coating formula led to decrease in drug release and increasing the curing temperature and time resulted in higher drug release. The optimization process generated an optimum of 35% drug release at 3 hr. The level of plasticizer concentration, curing temperature and time were 20% w/w, 55 °C and 24 hr, respectively. Conclusion: This study showed that by controllinig the physical variables optimum drug release were obtained. PMID:26351563

Image-based overlay and alignment metrology through optically opaque media with sub-surface probe microscopy

NASA Astrophysics Data System (ADS)

van Es, Maarten H.; Mohtashami, Abbas; Piras, Daniele; Sadeghian, Hamed

2018-03-01

Nondestructive subsurface nanoimaging through optically opaque media is considered to be extremely challenging and is essential for several semiconductor metrology applications including overlay and alignment and buried void and defect characterization. The current key challenge in overlay and alignment is the measurement of targets that are covered by optically opaque layers. Moreover, with the device dimensions moving to the smaller nodes and the issue of the so-called loading effect causing offsets between between targets and product features, it is increasingly desirable to perform alignment and overlay on product features or so-called on-cell overlay, which requires higher lateral resolution than optical methods can provide. Our recently developed technique known as SubSurface Ultrasonic Resonance Force Microscopy (SSURFM) has shown the capability for high-resolution imaging of structures below a surface based on (visco-)elasticity of the constituent materials and as such is a promising technique to perform overlay and alignment with high resolution in upcoming production nodes. In this paper, we describe the developed SSURFM technique and the experimental results on imaging buried features through various layers and the ability to detect objects with resolution below 10 nm. In summary, the experimental results show that the SSURFM is a potential solution for on-cell overlay and alignment as well as detecting buried defects or voids and generally metrology through optically opaque layers.

Preparation and evaluation of metoprolol tartrate sustained-release pellets using hot melt extrusion combined with hot melt coating.

PubMed

Yang, Yan; Shen, Lian; Li, Juan; Shan, Wei-Guang

2017-06-01

The objective of this study was to prepare and evaluate metoprolol tartrate sustained-release pellets. Cores were prepared by hot melt extrusion and coated pellets were prepared by hot melt coating. Cores were found to exist in a single-phase state and drug in amorphous form. Plasticizers had a significant effect on torque and drug content, while release modifiers and coating level significantly affected the drug-release behavior. The mechanisms of drug release from cores and coated pellets were Fickian diffusion and diffusion-erosion. The coated pellets exhibited sustained-release properties in vitro and in vivo.

Buried object detection in GPR images

DOEpatents

Paglieroni, David W; Chambers, David H; Bond, Steven W; Beer, W. Reginald

2014-04-29

A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across the surface and that travels down the surface. The imaging and detection system pre-processes the return signal to suppress certain undesirable effects. The imaging and detection system then generates synthetic aperture radar images from real aperture radar images generated from the pre-processed return signal. The imaging and detection system then post-processes the synthetic aperture radar images to improve detection of subsurface objects. The imaging and detection system identifies peaks in the energy levels of the post-processed image frame, which indicates the presence of a subsurface object.

Elastic Bottom Propagation Mechanisms Investigated by Parabolic Equation Methods

DTIC Science & Technology

2014-09-30

channel propagation of oceanic T waves from seismic sources in the presence of intervening seamounts or coral reef barriers is established using elastic PE...environments in the form of scattering at an elastic interface, oceanic T - waves , and Scholte waves . OBJECTIVES To implement explosive and earthquake...oceanic T - waves , which are acoustic waves that result from earthquake or buried explosive sources, and Rayleigh-type waves along the ocean floor, whose

A Spatial Display for Ground-Penetrating Radar Change Detection

DTIC Science & Technology

2013-09-01

rights reserved. Author ............................ Department of Electrical Engineering and Computer Science September 1, 2013 Certified by...a new member of the Lincoln community. Thank you, Rebecca, for being you and being here with me at MIT. I would like to thank my parents for their...alteration in the height of dirt under it. This capability will raise the chance of detecting a place where someone buried an object by detecting the

Robotic Range Clearance Competition (R2C2)

DTIC Science & Technology

2011-10-01

unexploded ordnance (UXO). A large part of the debris field consists of ferrous metal objects that magnetic 39 Distribution A: Approved for public...was set at 7 degrees above horizontal based on terrain around the Base station. We used the BSUBR file for all fields except the Subsurface...and subsurface clearance test areas had numerous pieces of simulated unexploded ordinance (SUXO) buried at random locations around the field . These

A comparison of robust principal component analysis techniques for buried object detection in downward looking GPR sensor data

NASA Astrophysics Data System (ADS)

Pinar, Anthony; Havens, Timothy C.; Rice, Joseph; Masarik, Matthew; Burns, Joseph; Thelen, Brian

2016-05-01

Explosive hazards are a deadly threat in modern conflicts; hence, detecting them before they cause injury or death is of paramount importance. One method of buried explosive hazard discovery relies on data collected from ground penetrating radar (GPR) sensors. Threat detection with downward looking GPR is challenging due to large returns from non-target objects and clutter. This leads to a large number of false alarms (FAs), and since the responses of clutter and targets can form very similar signatures, classifier design is not trivial. One approach to combat these issues uses robust principal component analysis (RPCA) to enhance target signatures while suppressing clutter and background responses, though there are many versions of RPCA. This work applies some of these RPCA techniques to GPR sensor data and evaluates their merit using the peak signal-to-clutter ratio (SCR) of the RPCA-processed B-scans. Experimental results on government furnished data show that while some of the RPCA methods yield similar results, there are indeed some methods that outperform others. Furthermore, we show that the computation time required by the different RPCA methods varies widely, and the selection of tuning parameters in the RPCA algorithms has a major effect on the peak SCR.

Aesthetic coatings for concrete bridge components

NASA Astrophysics Data System (ADS)

Kriha, Brent R.

This thesis evaluated the durability and aesthetic performance of coating systems for utilization in concrete bridge applications. The principle objectives of this thesis were: 1) Identify aesthetic coating systems appropriate for concrete bridge applications; 2) Evaluate the performance of the selected systems through a laboratory testing regimen; 3) Develop guidelines for coating selection, surface preparation, and application. A series of site visits to various bridges throughout the State of Wisconsin provided insight into the performance of common coating systems and allowed problematic structural details to be identified. To aid in the selection of appropriate coating systems, questionnaires were distributed to coating manufacturers, bridge contractors, and various DOT offices to identify high performing coating systems and best practices for surface preparation and application. These efforts supplemented a literature review investigating recent publications related to formulation, selection, surface preparation, application, and performance evaluation of coating materials.

Development of YAG:Dy Thermographic Phosphor Coatings for Turbine Engine Applications

NASA Technical Reports Server (NTRS)

Eldridge, J. I.; Jenkins, T. P.; Allison, S. W.; Wolfe, D. E.; Jordan, E. H.

2012-01-01

The selection and development of thermographic phosphor coatings were pursued to meet the objective of demonstrating luminescence-decay-based temperature measurements up to 1300C on the surface of a vane in an operating demonstrator turbine engine. To meet this objective, YAG:Dy was selected based on the desirable luminescence performance observed for YAG:Dy powder: (1) excellent temperature sensitivity and intensity at operating turbine engine temperatures, (2) an emission peak at the relatively short wavelength of 456 nm, where the interference from background blackbody radiation is fairly low, and (3) its nearly single exponential decay which makes for a simple, reliable temperature calibration. However, implementation of YAG:Dy for surface temperature measurements required application of YAG:Dy as a coating onto the surface of a superalloy component with a preexisting yttria-stabilized zirconia (YSZ) thermal barrier coating (TBC). An inherent dilemma in producing a YAG:Dy coating is that coating processing is constrained to be performed at temperatures below (less than 1200C) what is considered safe for the superalloy component, much lower than temperatures used to produce the high quality crystalline powder. Therefore, YAG:Dy coatings tend to exhibit lower luminescence performance compared to well prepared YAG:Dy powder, and the luminescence performance of the coating will depend on the method of coating deposition. In this presentation, the luminescence performance of YAG:Dy coatings prepared by the different methods of (1) application of a binder-based YAG:Dy-containing paint, (2) solution precursor plasma spray (SPPS), and (3) electron-beam physical vapor deposition (EB-PVD) and the effect of post-deposition heat treatments will be discussed.

Surface Instabilities From Buried Explosives

DTIC Science & Technology

2009-07-21

interface between soil and air during buried explosions. The purpose of understanding this instability is to determine its effect on local vehicle loading...Except when the target is on the surface, e.g., a tank track, the most important loading mechanism from a buried charge is the impact of soil propelled...rising soil and the air. This unstable 15. SUBJECT TERMS Buried Explosions, Richtmyer-Meshkov Instability, Target Loading, Jetting, 16 SECURITY

Influence of contaminant burial depth on the bioaccumulation of PCBs and PBDEs by two benthic invertebrates (Monoporeia affinis and Marenzelleria spp.).

PubMed

Josefsson, Sarah; Leonardsson, Kjell; Gunnarsson, Jonas S; Wiberg, Karin

2011-11-01

The bioaccumulation of buried polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) added to specific depths in sediment (2.0-2.5, 5.0-5.5 and 10.0-10.5cm) was studied in two infaunal species with similar feeding habits (surface deposit-feeders) but different bioturbation modes. The deep-burrowing polychaetes Marenzelleria spp. (Mz) displayed up to 36 times higher tissue concentrations of buried (spiked) contaminants than the surface-dwelling biodiffusing amphipod Monoporeia affinis. The differences in bioaccumulation were most pronounced for less hydrophobic contaminants due to the bioirrigating activity of Mz. Contaminants buried at shallow depths displayed higher accumulation than more deeply buried contaminants. In contrast, the bioaccumulation of unspiked (native) contaminants with a uniform vertical distribution in the sediment was similar between the species. For Mz, the BSAFs increased with increased K(OW) for the uniformly distributed contaminants, but decreased for the buried contaminants, which indicates that the dominant uptake routes of the buried contaminants can differ from the uniformly distributed contaminants. The surface sediment concentration of buried contaminants increased in Mz treatments, showing that Mz bioturbation can remobilize historically buried contaminants to the biologically active surface layer and increase the exposure for surface-dwelling species. Copyright © 2011 Elsevier Ltd. All rights reserved.

Structural and thermodynamic consequences of burial of an artificial ion pair in the hydrophobic interior of a protein.

PubMed

Robinson, Aaron C; Castañeda, Carlos A; Schlessman, Jamie L; García-Moreno, E Bertrand

2014-08-12

An artificial charge pair buried in the hydrophobic core of staphylococcal nuclease was engineered by making the V23E and L36K substitutions. Buried individually, Glu-23 and Lys-36 both titrate with pKa values near 7. When buried together their pKa values appear to be normal. The ionizable moieties of the buried Glu-Lys pair are 2.6 Å apart. The interaction between them at pH 7 is worth 5 kcal/mol. Despite this strong interaction, the buried Glu-Lys pair destabilizes the protein significantly because the apparent Coulomb interaction is sufficient to offset the dehydration of only one of the two buried charges. Save for minor reorganization of dipoles and water penetration consistent with the relatively high dielectric constant reported by the buried ion pair, there is no evidence that the presence of two charges in the hydrophobic interior of the protein induces any significant structural reorganization. The successful engineering of an artificial ion pair in a highly hydrophobic environment suggests that buried Glu-Lys pairs in dehydrated environments can be charged and that it is possible to engineer charge clusters that loosely resemble catalytic sites in a scaffold protein with high thermodynamic stability, without the need for specialized structural adaptations.

Structural and thermodynamic consequences of burial of an artificial ion pair in the hydrophobic interior of a protein

PubMed Central

Robinson, Aaron C.; Castañeda, Carlos A.; Schlessman, Jamie L.; García-Moreno E., Bertrand

2014-01-01

An artificial charge pair buried in the hydrophobic core of staphylococcal nuclease was engineered by making the V23E and L36K substitutions. Buried individually, Glu-23 and Lys-36 both titrate with pKa values near 7. When buried together their pKa values appear to be normal. The ionizable moieties of the buried Glu–Lys pair are 2.6 Å apart. The interaction between them at pH 7 is worth 5 kcal/mol. Despite this strong interaction, the buried Glu–Lys pair destabilizes the protein significantly because the apparent Coulomb interaction is sufficient to offset the dehydration of only one of the two buried charges. Save for minor reorganization of dipoles and water penetration consistent with the relatively high dielectric constant reported by the buried ion pair, there is no evidence that the presence of two charges in the hydrophobic interior of the protein induces any significant structural reorganization. The successful engineering of an artificial ion pair in a highly hydrophobic environment suggests that buried Glu–Lys pairs in dehydrated environments can be charged and that it is possible to engineer charge clusters that loosely resemble catalytic sites in a scaffold protein with high thermodynamic stability, without the need for specialized structural adaptations. PMID:25074910

Solar Absorptance of Cermet Coatings Evaluated

NASA Technical Reports Server (NTRS)

Jaworske, Donald A.

2004-01-01

Cermet coatings, molecular mixtures of metal and ceramic, are being considered for the heat inlet surface of solar Stirling convertors. In this application, the key role of the cermet coating is to absorb as much of the incident solar energy as possible. To achieve this objective, the cermet coating has a high solar absorptance value. Cermet coatings are manufactured utilizing sputter deposition, and many different metal and ceramic combinations can be created. The ability to mix metal and ceramic at the atomic level offers the opportunity to tailor the composition, and hence, the optical properties of these coatings. The NASA Glenn Research Center has prepared and characterized a wide variety of cermet coatings utilizing different metals deposited in an aluminum oxide ceramic matrix. In addition, the atomic oxygen durability of these coatings has been evaluated.

Method and apparatus for increasing resistance of bipolar buried layer integrated circuit devices to single-event upsets

NASA Technical Reports Server (NTRS)

Zoutendyk, John A. (Inventor)

1991-01-01

Bipolar transistors fabricated in separate buried layers of an integrated circuit chip are electrically isolated with a built-in potential barrier established by doping the buried layer with a polarity opposite doping in the chip substrate. To increase the resistance of the bipolar transistors to single-event upsets due to ionized particle radiation, the substrate is biased relative to the buried layer with an external bias voltage selected to offset the built-in potential just enough (typically between about +0.1 to +0.2 volt) to prevent an accumulation of charge in the buried-layer-substrate junction.

Dependence of the Carrier Transport Characteristics on the Buried Layer Thickness in Ambipolar Double-Layer Organic Field-Effect Transistors Investigated by Electrical and Optical Measurements

NASA Astrophysics Data System (ADS)

Zhang, Le; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa

2013-05-01

By using current-voltage (I-V) measurements and optical modulation spectroscopy, we investigated the dependence of the carrier behaviour on the film thickness of the buried pentacene layer in C60/pentacene ambipolar double-layer organic field-effect transistors (OFETs). It was found that the buried pentacene layer not only acted as a hole transport layer, but also accounted for the properties of the C60/pentacene interface. The hole and electron behaviour exhibited different thickness dependence on the buried pentacene layer, implying the presence of the spatially separated conduction paths. It was suggested that the injected holes transported along the pentacene/gate dielectric interface, which were little affected by the buried pentacene layer thickness or the upper C60 layer; while, the injected electrons accumulated at the C60/pentacene interface, which were sensitive to the interfacial conditions or the buried pentacene layer. Furthermore, it was suggested that the enhanced surface roughness of the buried pentacene layer was responsible for the observed electron behaviour, especially when dpent>10 nm.

Location of coating defects and assessment of level of cathodic protection on underground pipelines using AC impedance, deterministic and non-deterministic models

NASA Astrophysics Data System (ADS)

Castaneda-Lopez, Homero

A methodology for detecting and locating defects or discontinuities on the outside covering of coated metal underground pipelines subjected to cathodic protection has been addressed. On the basis of wide range AC impedance signals for various frequencies applied to a steel-coated pipeline system and by measuring its corresponding transfer function under several laboratory simulation scenarios, a physical laboratory setup of an underground cathodic-protected, coated pipeline was built. This model included different variables and elements that exist under real conditions, such as soil resistivity, soil chemical composition, defect (holiday) location in the pipeline covering, defect area and geometry, and level of cathodic protection. The AC impedance data obtained under different working conditions were used to fit an electrical transmission line model. This model was then used as a tool to fit the impedance signal for different experimental conditions and to establish trends in the impedance behavior without the necessity of further experimental work. However, due to the chaotic nature of the transfer function response of this system under several conditions, it is believed that non-deterministic models based on pattern recognition algorithms are suitable for field condition analysis. A non-deterministic approach was used for experimental analysis by applying an artificial neural network (ANN) algorithm based on classification analysis capable of studying the pipeline system and differentiating the variables that can change impedance conditions. These variables include level of cathodic protection, location of discontinuities (holidays), and severity of corrosion. This work demonstrated a proof-of-concept for a well-known technique and a novel algorithm capable of classifying impedance data for experimental results to predict the exact location of the active holidays and defects on the buried pipelines. Laboratory findings from this procedure are promising, and efforts to develop it for field conditions should continue.

Application of morphological associative memories and Fourier descriptors for classification of noisy subsurface signatures

NASA Astrophysics Data System (ADS)

Ortiz, Jorge L.; Parsiani, Hamed; Tolstoy, Leonid

2004-02-01

This paper presents a method for recognition of Noisy Subsurface Images using Morphological Associative Memories (MAM). MAM are type of associative memories that use a new kind of neural networks based in the algebra system known as semi-ring. The operations performed in this algebraic system are highly nonlinear providing additional strength when compared to other transformations. Morphological associative memories are a new kind of neural networks that provide a robust performance with noisy inputs. Two representations of morphological associative memories are used called M and W matrices. M associative memory provides a robust association with input patterns corrupted by dilative random noise, while the W associative matrix performs a robust recognition in patterns corrupted with erosive random noise. The robust performance of MAM is used in combination of the Fourier descriptors for the recognition of underground objects in Ground Penetrating Radar (GPR) images. Multiple 2-D GPR images of a site are made available by NASA-SSC center. The buried objects in these images appear in the form of hyperbolas which are the results of radar backscatter from the artifacts or objects. The Fourier descriptors of the prototype hyperbola-like and shapes from non-hyperbola shapes in the sub-surface images are used to make these shapes scale-, shift-, and rotation-invariant. Typical hyperbola-like and non-hyperbola shapes are used to calculate the morphological associative memories. The trained MAMs are used to process other noisy images to detect the presence of these underground objects. The outputs from the MAM using the noisy patterns may be equal to the training prototypes, providing a positive identification of the artifacts. The results are images with recognized hyperbolas which indicate the presence of buried artifacts. A model using MATLAB has been developed and results are presented.

High-performance a-IGZO thin-film transistor with conductive indium-tin-oxide buried layer

NASA Astrophysics Data System (ADS)

Ahn, Min-Ju; Cho, Won-Ju

2017-10-01

In this study, we fabricated top-contact top-gate (TCTG) structure of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) with a thin buried conductive indium-tin oxide (ITO) layer. The electrical performance of a-IGZO TFTs was improved by inserting an ITO buried layer under the IGZO channel. Also, the effect of the buried layer's length on the electrical characteristics of a-IGZO TFTs was investigated. The electrical performance of the transistors improved with increasing the buried layer's length: a large on/off current ratio of 1.1×107, a high field-effect mobility of 35.6 cm2/Vs, a small subthreshold slope of 116.1 mV/dec, and a low interface trap density of 4.2×1011 cm-2eV-1 were obtained. The buried layer a-IGZO TFTs exhibited enhanced transistor performance and excellent stability against the gate bias stress.

Theoretical investigation of metal magnetic memory testing technique for detection of magnetic flux leakage signals from buried defect

NASA Astrophysics Data System (ADS)

Xu, Kunshan; Qiu, Xingqi; Tian, Xiaoshuai

2018-01-01

The metal magnetic memory testing (MMMT) technique has been extensively applied in various fields because of its unique advantages of easy operation, low cost and high efficiency. However, very limited theoretical research has been conducted on application of MMMT to buried defects. To promote study in this area, the equivalent magnetic charge method is employed to establish a self-magnetic flux leakage (SMFL) model of a buried defect. Theoretical results based on the established model successfully capture basic characteristics of the SMFL signals of buried defects, as confirmed via experiment. In particular, the newly developed model can calculate the buried depth of a defect based on the SMFL signals obtained via testing. The results show that the new model can successfully assess the characteristics of buried defects, which is valuable in the application of MMMT in non-destructive testing.

LDEF-space environmental effects on materials: Composites and silicone coatings

NASA Technical Reports Server (NTRS)

Petrie, Brian C.

1991-01-01

The objective of the Lockheed experiment is to evaluate the effects of long term low Earth orbit environments on thermal control coatings and organic matrix/fiber reinforced composites. Two diverse categories are reported: silicone coatings and composites. For composites physical and structural properties were analyzed; results are reported on mass/dimensional loss, microcracking, short beam shear, CTE, and flexural properties. The changes in thermal control properties, mass, and surface chemistry and morphology are reported and analyzed for the silicon coatings.

A comparison between decomposition rates of buried and surface remains in a temperate region of South Africa.

PubMed

Marais-Werner, Anátulie; Myburgh, J; Becker, P J; Steyn, M

2018-01-01

Several studies have been conducted on decomposition patterns and rates of surface remains; however, much less are known about this process for buried remains. Understanding the process of decomposition in buried remains is extremely important and aids in criminal investigations, especially when attempting to estimate the post mortem interval (PMI). The aim of this study was to compare the rates of decomposition between buried and surface remains. For this purpose, 25 pigs (Sus scrofa; 45-80 kg) were buried and excavated at different post mortem intervals (7, 14, 33, 92, and 183 days). The observed total body scores were then compared to those of surface remains decomposing at the same location. Stages of decomposition were scored according to separate categories for different anatomical regions based on standardised methods. Variation in the degree of decomposition was considerable especially with the buried 7-day interval pigs that displayed different degrees of discolouration in the lower abdomen and trunk. At 14 and 33 days, buried pigs displayed features commonly associated with the early stages of decomposition, but with less variation. A state of advanced decomposition was reached where little change was observed in the next ±90-183 days after interment. Although the patterns of decomposition for buried and surface remains were very similar, the rates differed considerably. Based on the observations made in this study, guidelines for the estimation of PMI are proposed. This pertains to buried remains found at a depth of approximately 0.75 m in the Central Highveld of South Africa.

The role of dung beetles as a secondary seed disperser after dispersal by frugivore mammals in a temperate deciduous forest

NASA Astrophysics Data System (ADS)

Koike, Shinsuke; Morimoto, Hideto; Kozakai, Chinatsu; Arimoto, Isao; Soga, Masashi; Yamazaki, Koji; Koganezawa, Masaaki

2012-05-01

We studied the effects of dung beetles on the fates of endozoochorous seeds of five species (Prunus jamasakura, Prunus verecunda, Prunus grayana, Swida controversa, and Vitis coignetiae) in a temperate deciduous forest in Japan during 2004-2006. In field experiments using dung of the Asiatic black bear (Ursus thibetanus), we investigated the depths that dung beetles (Onthophagus atripennis, Onthophagus lenzii, and Phelotrupes auratus) buried seeds (4.8-6.8 mm diameter) and plastic markers (2 or 5 mm diameter), the levels of predation on buried and unburied seeds, and germination rates of seeds buried to different depths. All three species buried the 2-mm markers, but only P. auratus buried the seeds and 5-mm markers. There were seasonal differences in mean seed burial rates (range, 27-51%) and depths (range, 1-27 mm). Significantly more seeds were buried in June, July, and September than in August or October, and the mean burial depth was significantly deeper in June and July. Most seeds and markers were buried to a 3-6 cm depth. Germination of seeds that were positioned at depths of 1-4 cm was significantly greater than that of seeds left on the surface or buried at greater depths. Buried seeds were less likely to disappear than seeds at the surface, which may reflect differential predation. These results suggested that dung beetles, especially P. auratus, acted as a secondary seed disperser that affected the survival and distribution of seeds dispersed by a frugivore.

Possible alternatives to critical elements in coatings for extreme applications

NASA Astrophysics Data System (ADS)

Grilli, Maria Luisa; Valerini, Daniele; Piticescu, Radu Robert; Bellezze, Tiziano; Yilmaz, Mehmet; Rinaldi, Antonio; Cuesta-López, Santiago; Rizzo, Antonella

2018-03-01

Surface functionalisation and protection have been used since a long time for improving specific properties of materials such as lubrication, water repellence, brightness, and for increasing durability of objects and tools. Among the different kinds of surface treatments used to achieve the required properties, the use of coatings is fundamental to guarantee substrate durability in harsh environments. Extreme working conditions of temperature, pressure, irradiation, wear and corrosion occur in several applications, thus very often requiring bulk material protection by means of coatings. In this study, three main classes of coatings used in extreme conditions are considered: i) hard and superhard coatings for application in machining tools, ii) coatings for high temperatures (thermal barrier coatings), and iii) coatings against corrosion. The presence of critical elements in such coatings (Cr, Y, W, Co, etc.) is analysed and the possibility to use CRMs-free substitutes is reviewed. The role of multilayers and nanocomposites in tailoring coating performances is also discussed for thermal barrier and superhard coatings.

Erosion-Resistant Nanocoatings for Improved Energy Efficiency in Gas Turbines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alman, David; Marcio, Duffles

2014-02-05

The objective of this Stage Gate IV project was to test and substantiate the viability of an erosion-resistant nanocoating for application on compressor airfoils for gas turbines in both industrial power generation and commercial aviation applications. To effectively complete this project, the National Energy Technology Laboratory’s Office of Research & Development teamed with MDS Coating Technologies Inc. (MCT), Delta Air Lines - Technical Operations Division (Delta Tech Ops), and Calpine Corporation. The coating targeted for this application was MCT’s Next Generation Coating, version 4 (NGC-v4 - with the new registered trademark name of BlackGold®). The coating is an erosion andmore » corrosion resistant composite nanostructured coating. This coating is comprised of a proprietary ceramic-metallic nano-composite construction which provides enhanced erosion resistance and also retains the aerodynamic geometry of the airfoils. The objective of the commercial aviation portion of the project was to substantiate the coating properties to allow certification from the FAA to apply an erosion-resistant coating in a commercial aviation engine. The goal of the series of tests was to demonstrate that the durability of the airfoils is not affected negatively with the application of the NGC v4 coating. Tests included erosion, corrosion, vibration and fatigue. The results of the testing demonstrated that the application of the coating did not negatively impact the properties of the blades, especially fatigue performance – which is of importance in acceptance for commercial aviation applications. The objective of the industrial gas turbine element of the project was to evaluate the coating as an enabling technology for inlet fogging during the operation of industrial gas turbines. Fluid erosion laboratory scale tests were conducted to simulate inlet fogging conditions. Results of these tests indicated that the application of the erosion resistant NGC-v4 nanocoating improved the resistance to simulated inlet fogging conditions by a factor of 10 times. These results gave confidence for a field trial at Calpine’s power plant in Corpus Christi, TX, which commenced in April 2012. This test is still on-going as of November 2013, and the nanocoated blades have accumulated over 13,000 operational hours on this specific power plant in approximately 19 months of operation.« less

The burial of headwater streams in drainage pipes reduces in-stream nitrate retention: results from two US metropolitan areas

NASA Astrophysics Data System (ADS)

Beaulieu, J. J.; Mayer, P. M.; Kaushal, S.; Pennino, M. J.; Arango, C. P.; Balz, D. A.; Fritz, K. M.; Golden, H. E.; Knightes, C. D.

2012-12-01

Nitrogen (N) retention in stream networks is an important ecosystem service that may be affected by the widespread burial of headwater streams in urban watersheds. Stream burial occurs when segments of a channel are encased in drainage pipe and buried beneath the land surface to facilitate above ground development or stormwater runoff. We predicted that burial suppresses the capacity of streams to retain and transform nitrate, the dominate form of bioavailable N in urban streams, by eliminating primary production, reducing respiration rates, and decreasing water residence time. We tested these predictions by measuring whole-stream nitrate (NO3-) removal rates using 15NO3- isotope tracer releases in reaches that were buried and open to the sunlight in three streams in Cincinnati, Ohio and three streams in Baltimore, Maryland during four seasons. Nitrate uptake lengths in buried reaches (range: 560 - 43,650 m) were 2-98 times greater than open reaches exposed to daylight (range: 85 - 7195 m), indicating that buried reaches were substantially less effective at retaining NO3- than open reaches. Nitrate retention in buried reaches was suppressed by a combination of hydrological and biological processes. High water velocities in buried reaches (buried= 5.8 m/s, open=1.48 m/s) rapidly exported NO3- from the channel, reducing the potential for in-stream NO3- retention. Uptake lengths in the buried reaches were lengthened further by low in-stream biological NO3- demand, as indicated by NO3- uptake velocities 16-fold lower than that of the open reaches. Similarly, buried reaches had lower ecosystem respiration rates than open reaches (buried=1.5g O2/m2/hr, open=4.5g O2/m2/hr), likely due to lower organic matter standing stocks (buried=12 gAFMD/m2, open=48 gAFDM/m2). Biological activity in the buried reaches was further suppressed by the absence of light which precluded photosynthetic activity and the associated assimilative N demand. Overall, our results demonstrate that the combined effects of elevated water velocity and reduced biological activity as a result of stream burial inhibits NO3- retention, exacerbating the export of excess N to downstream water bodies. Future work will scale these results to a river network to assess the cumulative effect of stream burial on watershed NO3- export.

Thermal control/oxidation resistant coatings for titanium-based alloys

NASA Technical Reports Server (NTRS)

Clark, Ronald K.; Wallace, Terryl A.; Cunnington, George R.; Wiedemann, Karl E.

1992-01-01

Extensive research and development efforts have been expended toward development of thermal control and environmental protection coatings for NASP and generic hypersonic vehicle applications. The objective of the coatings development activities summarized here was to develop light-weight coatings for protecting advanced titanium alloys from oxidation in hypersonic vehicle applications. A number of new coating concepts have been evaluated. Coated samples were exposed to static oxidation tests at temperatures up to 1000 C using a thermogravimetric apparatus. Samples were also exposed to simulated hypersonic flight conditions for up to 10 hr to determine their thermal and chemical stability and catalytic efficiency. The emittance of samples was determined before and after exposure to simulated hypersonic flight conditions.

Evaluation and Validation of Aboveground Techniques for Coating Condition Assessment

DOT National Transportation Integrated Search

2006-02-28

The overall objective was to determine the accuracy, resolution, and limitations of equipment typically used for modern aboveground ECDA work with respect to locating holidays and disbondments with commonly used coatings with varying spatial relation...

Environmentally-Preferable Launch Coatings

NASA Technical Reports Server (NTRS)

Kessel, Kurt R.

2015-01-01

The Ground Systems Development and Operations (GSDO) Program at NASA Kennedy Space Center (KSC), Florida, has the primary objective of modernizing and transforming the launch and range complex at KSC to benefit current and future NASA programs along with other emerging users. Described as the launch support and infrastructure modernization program in the NASA Authorization Act of 2010, the GSDO Program will develop and implement shared infrastructure and process improvements to provide more flexible, affordable, and responsive capabilities to a multi-user community. In support of NASA and the GSDO Program, the objective of this project is to determine the feasibility of environmentally friendly corrosion protecting coatings for launch facilities and ground support equipment (GSE). The focus of the project is corrosion resistance and survivability with the goal to reduce the amount of maintenance required to preserve the performance of launch facilities while reducing mission risk. The project compares coating performance of the selected alternatives to existing coating systems or standards.

Residual Stresses in a NiCrY-Coated Powder Metallurgy Disk Superalloy

NASA Technical Reports Server (NTRS)

Gabb, Timothy P.; Rogers, Richard B.; Nesbitt, James A.; Puleo, Bernadette J.; Miller, Robert A.; Telesman, Ignacy; Draper, Susan L.; Locci, Ivan E.

2017-01-01

Protective ductile coatings will be necessary to mitigate oxidation and corrosion attack on superalloy disks exposed to increasing operating temperatures in some turbine engine environments. However, such coatings must be resistant to harmful surface cracking during service. The objective of this study was to investigate how residual stresses evolve in such coatings. Cylindrical gage fatigue specimens of powder metallurgy-processed disk superalloy LSHR were coated with a NiCrY coating, shot peened, and then subjected to fatigue in air at room and high temperatures. The effects of shot peening and fatigue cycling on average residual stresses and other aspects of the coating were assessed. Shot peening did induce beneficial compressive residual stresses in the coating and substrate. However, these stresses became more tensile in the coating with subsequent heating and contributed to cracking of the coating in long intervals of cycling at 760 C. Substantial compressive residual stresses remained in the substrate adjacent to the coating, sufficient to suppress fatigue cracking. The coating continued to protect the substrate from hot corrosion pitting, even after fatigue cracks initiated in the coating.

Process for coating an object with silicon carbide

NASA Technical Reports Server (NTRS)

Levin, Harry (Inventor)

1989-01-01

A process for coating a carbon or graphite object with silicon carbide by contacting it with silicon liquid and vapor over various lengths of contact time. In the process, a stream of silicon-containing precursor material in gaseous phase below the decomposition temperature of said gas and a co-reactant, carrier or diluent gas such as hydrogen is passed through a hole within a high emissivity, thin, insulating septum into a reaction chamber above the melting point of silicon. The thin septum has one face below the decomposition temperature of the gas and an opposite face exposed to the reaction chamber. The precursor gas is decomposed directly to silicon in the reaction chamber. A stream of any decomposition gas and any unreacted precursor gas from said reaction chamber is removed. The object within the reaction chamber is then contacted with silicon, and recovered after it has been coated with silicon carbide.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weiss, Paul

Spectroscopic imaging tools and methods, based on scanning tunneling microscopes (STMs), are being developed and applied to examine buried layers and interfaces with ultrahigh resolution. These new methods measure buried contacts, molecule-substrate bonds, buried dipoles in molecular layers, and key structural aspects of adsorbed molecules, such as tilt angles. We are developing the ability to locate lateral projections of molecular parts as a means of determining the structures of molecular layers. We are developing the ability to measure the orientation of buried functionality.

Centrifugal and Numerical Modeling of Buried Structures. Volume 2. Dynamic Soil-Structure Interaction.

DTIC Science & Technology

1987-07-14

RD-RISE 368 CENTRIFUGAL AND NUMERICAL MODELING OF BURIED STRUCTURES 1/3 VOLUME 2 DYNAMIC..(U) COLORADO UNIV AT BOULDER DEPT OF CIVIL ENVIRONMENTAL...20332-6448 ELEMENT NO NO. NO ACCESSION NO 61102F 2302 Cl 11 TITLE (Include Security Classification) (U) Centrifugal and Numerical Modeling of Buried ...were buried in a dry sand and tested in the centrifuge to simulate the effects of gravity-induced overburden stresses which played a major role in

Room temperature continuous wave operation of quantum cascade laser at λ ~ 9.4 μm

NASA Astrophysics Data System (ADS)

Hou, Chuncai; Zhao, Yue; Zhang, Jinchuan; Zhai, Shenqiang; Zhuo, Ning; Liu, Junqi; Wang, Lijun; Liu, Shuman; Liu, Fengqi; Wang, Zhanguo

2018-03-01

Continuous wave (CW) operation of long wave infrared (LWIR) quantum cascade lasers (QCLs) is achieved up to a temperature of 303 K. For room temperature CW operation, the wafer with 35 stages was processed into buried heterostructure lasers. For a 2-mm-long and 10-μm-wide laser with high-reflectivity (HR) coating on the rear facet, CW output power of 45 mW at 283 K and 9 mW at 303 K is obtained. The lasing wavelength is around 9.4 μm locating in the LWIR spectrum range. Project supported by the National Key Research And Development Program (No. 2016YFB0402303), the National Natural Science Foundation of China (Nos. 61435014, 61627822, 61574136, 61774146, 61674144, 61404131), the Key Projects of Chinese Academy of Sciences (Nos. ZDRW-XH-2016-4, QYZDJ-SSW-JSC027), and the Beijing Natural Science Foundation (No. 4162060, 4172060).

Low Power Consumption Substrate-Emitting DFB Quantum Cascade Lasers.

PubMed

Liu, Chuan-Wei; Zhang, Jin-Chuan; Jia, Zhi-Wei; Zhuo, Ning; Zhai, Shen-Qiang; Wang, Li-Jun; Liu, Jun-Qi; Liu, Shu-Man; Liu, Feng-Qi; Wang, Zhan-Guo

2017-09-02

In the present work, an ultra-low power consumption substrate-emitting distributed feedback (DFB) quantum cascade laser (QCL) was developed. The continuous-wave (CW) threshold power dissipation is reduced to 0.43 W at 25 °C by shortening the cavity length to 0.5 mm and depositing high-reflectivity (HR) coating on both facets. As far as we know, this is the recorded threshold power dissipation of QCLs in the same conditions. Single-mode emission was achieved by employing a buried second-order grating. Mode-hop free emission can be observed within a wide temperature range from 15 to 105 °C in CW mode. The divergence angles are 22.5 o and 1.94 o in the ridge-width direction and cavity-length direction, respectively. The maximum optical power in CW operation was 2.4 mW at 25 °C, which is sufficient to spectroscopy applications.

Low Power Consumption Substrate-Emitting DFB Quantum Cascade Lasers

NASA Astrophysics Data System (ADS)

Liu, Chuan-Wei; Zhang, Jin-Chuan; Jia, Zhi-Wei; Zhuo, Ning; Zhai, Shen-Qiang; Wang, Li-Jun; Liu, Jun-Qi; Liu, Shu-Man; Liu, Feng-Qi; Wang, Zhan-Guo

2017-09-01

In the present work, an ultra-low power consumption substrate-emitting distributed feedback (DFB) quantum cascade laser (QCL) was developed. The continuous-wave (CW) threshold power dissipation is reduced to 0.43 W at 25 °C by shortening the cavity length to 0.5 mm and depositing high-reflectivity (HR) coating on both facets. As far as we know, this is the recorded threshold power dissipation of QCLs in the same conditions. Single-mode emission was achieved by employing a buried second-order grating. Mode-hop free emission can be observed within a wide temperature range from 15 to 105 °C in CW mode. The divergence angles are 22.5o and 1.94o in the ridge-width direction and cavity-length direction, respectively. The maximum optical power in CW operation was 2.4 mW at 25 °C, which is sufficient to spectroscopy applications.

Ultralow threshold graded-index separate-confinement heterostructure single quantum well (Al, Ga) As lasers

NASA Technical Reports Server (NTRS)

Derry, P. L.; Chen, H. Z.; Morkoc, H.; Yariv, A.; Lau, K. Y.

1988-01-01

Broad area graded-index separate-confinement heterostructure single quantum well lasers grown by molecular-beam epitaxy (MBE) with threshold current density as low as 93 A/sq cm (520 microns long) have been fabricated. Buried lasers formed from similarly structured MBE material with liquid phase epitaxy regrowth had threshold currents at submilliampere levels when high reflectivity coatings were applied to the end facets. A CW threshold current of 0.55 mA was obtained for a laser with facet reflectivities of about 80 percent, a cavity length of 120 micron, and an active region stripe width of 1 micron. These devices driven directly with logic level signals have switch-on delays less than 50 ps without any current prebias. Such lasers permit fully on-off switching while at the same time obviating the need for bias monitoring and feedback control.

A Label Propagation Approach for Detecting Buried Objects in Handheld GPR Data

DTIC Science & Technology

2016-04-17

regions of interest that correspond to locations with anomalous signatures. Second, a classifier (or an ensemble of classifiers ) is used to assign a...investigated for almost two decades and several classifiers have been developed. Most of these methods are based on the supervised learning paradigm where...labeled target and clutter signatures are needed to train a classifier to discriminate between the two classes. Typically, large and diverse labeled

Method of installing subsurface barrier

DOEpatents

Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

2007-10-09

Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

Subsurface materials management and containment system

DOEpatents

Nickelson, Reva A.; Richardson, John G.; Kosteinik, Kevin M.; Sloan, Paul A.

2004-07-06

Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

Subsurface materials management and containment system

DOEpatents

Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

2006-10-17

Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

Bedrock mapping of buried valley networks using seismic reflection and airborne electromagnetic data

NASA Astrophysics Data System (ADS)

Oldenborger, G. A.; Logan, C. E.; Hinton, M. J.; Pugin, A. J.-M.; Sapia, V.; Sharpe, D. R.; Russell, H. A. J.

2016-05-01

In glaciated terrain, buried valleys often host aquifers that are significant groundwater resources. However, given the range of scales, spatial complexity and depth of burial, buried valleys often remain undetected or insufficiently mapped. Accurate and thorough mapping of bedrock topography is a crucial step in detecting and delineating buried valleys and understanding formative valley processes. We develop a bedrock mapping procedure supported by the combination of seismic reflection data and helicopter time-domain electromagnetic data with water well records for the Spiritwood buried valley aquifer system in Manitoba, Canada. The limited spatial density of water well bedrock observations precludes complete depiction of the buried valley bedrock topography and renders the water well records alone inadequate for accurate hydrogeological model building. Instead, we leverage the complementary strengths of seismic reflection and airborne electromagnetic data for accurate local detection of the sediment-bedrock interface and for spatially extensive coverage, respectively. Seismic reflection data are used to define buried valley morphology in cross-section beneath survey lines distributed over a regional area. A 3D model of electrical conductivity is derived from inversion of the airborne electromagnetic data and used to extrapolate buried valley morphology over the entire survey area. A spatially variable assignment of the electrical conductivity at the bedrock surface is applied to different features of the buried valley morphology identified in the seismic cross-sections. Electrical conductivity is then used to guide construction of buried valley shapes between seismic sections. The 3D locus of points defining each morphological valley feature is constructed using a path optimization routine that utilizes deviation from the assigned electrical conductivities as the cost function. Our resulting map represents a bedrock surface of unprecedented detail with more complexity than has been suggested by previous investigations. Our procedure is largely data-driven with an adaptable degree of expert user input that provides a clear protocol for incorporating different types of geophysical data into the bedrock mapping procedure.

Optimal illusion and invisibility of multilayered anisotropic cylinders and spheres.

PubMed

Zhang, Lin; Shi, Yan; Liang, Chang-Hong

2016-10-03

In this paper, full-wave electromagnetic scattering theory is employed to investigate illusion and invisibility of inhomogeneous anisotropic cylinders and spheres. With the use of a shell designed according to Mie series theory for multiple piecewise anisotropic layers, radar cross section (RCS) of the coated inhomogeneous anisotropic object can be dramatically reduced or disguised as another object in the long-wavelength limit. With the suitable adjustment of the anisotropy parameters of the shell, optimal illusion and invisibility characteristics of the coated inhomogeneous anisotropic object can be achieved. Details of theoretical analysis and numerical examples are presented to validate the proposed methodology.

Hair shedding score may affect body temperature more than hair coat color during heat stress in weaned beef heifers.

USDA-ARS?s Scientific Manuscript database

The objective of this study was to evaluate the effect of hair shedding score and hair coat color on the vaginal temperature (VT) of calves during heat stress. Weaned Bos taurus beef heifers (n = 32; BW = 282 ± 6.4 kg) were assigned to a hair coat color class (BLACK; RED; or LIGHT, where LIGHT = yel...

Formulation of Ames 24E2 IR-black coating

NASA Technical Reports Server (NTRS)

Smith, Sheldon M.

1991-01-01

The formulation of Ames 24E2 IR-black coating and a rationale for the selection of its components are given. The objective was to make a very rough, very thick, and highly absorbing coating to attenuate the specular reflectance of telescope baffles at far-IR wavelengths. Application and curing instructions are also given. Outgassing measurements are quite low following a 24-hour radiative cure.

Tack Coat Performance and Materials Study

DOT National Transportation Integrated Search

2017-06-01

A good bond provided by a tack coat can improve performance of asphalt overlays. The objectives of this research were: (1) develop a method for testing the bond between pavement layers; (2) evaluate the bond performance and predict long-term performa...

Elevated Building Lift Systems on Permanent Snowfields: A Report on the Elevated Building Lift Systems in Polar Environments Workshop

DTIC Science & Technology

2014-09-18

the power plant and mechanical systems, the “Noisy” building, and the “Quiet” building...6040 m² Garage (buried): 835 m² Cargo Arch (buried) : 1640 m² Power Plant (buried) : 600 m² Fuel Arch (buried) : 1325 m² Habitat: 1640 m...Laboratory: 210 m² Garage: 2623 m² Total: 4473 m² Main Bldgs.: 1612 m² Power plant : 188 m² Population Summer: 52 Winter: 16 Summer (3 mo.): 150

A comprehensive inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the INEL RWMC during the years 1984-2003, Volume 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-05-01

This is the third volume of this comprehensive report of the inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the Idaho National Engineering Laboratory. Appendix B contains a complete printout of contaminant inventory and other information from the CIDRA Database and is presented in volumes 2 and 3 of the report.

Promotion of tribological and hydrophobic properties of a coating on TPE substrates by atmospheric plasma-polymerization

NASA Astrophysics Data System (ADS)

Sainz-García, Elisa; Alba-Elías, Fernando; Múgica-Vidal, Rodolfo; Pantoja-Ruiz, Mariola

2016-05-01

Thermoplastic elastomers (TPE) are used in the automotive sealing industry with the objective of producing anti-friction and hydrophobic components. At present, the anti-friction property is achieved by the electrostatic flocking, which sometimes produces an irregular coating. Therefore, this paper's objective is the promotion of adhesion of an anti-friction (based on the silane aminopropyltriethoxysilane-APTES-) and hydrophobic (based on the fluorinated precursor 1-perfluorohexene-PFH-) coating by the adhesion promoter, APTES. Different mixtures of APTES and PFH have been applied to a TPE substrate by an Atmospheric Pressure Plasma Jet (APPJ) system with Dielectric Barrier Discharge (DBD) in order to determine the optimal mixture of precursors. The main difficulty in this work lies in the hydrophilic character of APTES and the low adhesion of the fluorinated coatings. The sample coated with a mixture of 50% APTES and 50% PFH (A50P50) was found to be the best one to satisfy both properties at the same time, despite not having the highest dynamic water contact angle (WCA) or the lowest friction coefficient.

Integrated GPR and ERT as Enhanced Detection for Subsurface Historical Structures Inside Babylonian Houses Site, Uruk City, Southern Iraq

NASA Astrophysics Data System (ADS)

Al-Khersan, Emad H.; Al-Ani, Jassim M. T.; Abrahem, Salah N.

2016-03-01

Uruk archaeological site, which located in Al-Muthanna Governorate southern Iraq, was investigated by integrated geophysical methods, ground penetration radar (GPR) and electric resistivity tomography (ERT) to image the historical buried structures. The GPR images show large radar attributes characterized by its continuous reflections having different widths. GPR attributes at shallower depth are mainly representing the upper part of Babylonian Houses that can often be found throughout the study area. In addition, radargrams characterized objects such as buried items, buried trenches and pits which were mainly concentrated near the surface. The ERT results show the presence of several anomalies at different depths generally having low resistivities. It is clear that the first upper zone can be found throughout the whole area and it may represent the top zone of the Babylonian houses. This zone is characterized by its dry clay and sandy soil containing surface broken bricks and slag mixed with core boulders. The second one underneath the top shows a prominent lower resistivity zone. It is probably caused by the moisture content that reduces the resistivity. The thickness of this zone is not equal at all parts of the site. The third deeper zone typically represents the archaeological walls. Most of the main anomalies perhaps referred to the buried clay brick walls. The map of the archaeological anomalies distribution and 3D view of the foundations at the study area using GPR and ERT techniques clearly show the characteristics of the Babylonian remains. A contour map and 3D view of Uruk show that the archaeological anomalies are concentrated mainly at the NE part of the district with higher values of wall height that range between 6 and 8 m and reach to more than 10 m. At the other directions, there are fewer walls with lower heights of 4-6 m and reach in some places the wall foot.

Seasonal Variations in Resistivity at a Police Forensic Site and the Effectiveness of Unconventional Array Types

NASA Astrophysics Data System (ADS)

Edwards, S.; Bank, C. G.

2016-12-01

Geophysical studies involving the detection of buried organic material can be affected by the passage of time and environmental changes such as temperature and, in more importantly, water content in the ground. These effects can be of particular concern for police forensic investigations. This study involved conducting multiple resistivity surveys across 4 months to determine how time and environmental variations affected the detection of porcine carcasses buried four years previous at a provincial police training and research site. Our research also explored survey results of non-conventional grid and square arrays versus traditional linear arrays. The study site is located in Bolton, Ontario, and measures 16 m by 30 m. It contains 18 graves plus other buried objects. Studies were conducted approximately every other week. The resistivity lines used Wenner arrays of 24 m (0.5 m electrode spacing) and 48 m (1 m spacing) in length. Environmental data was obtained from Environment Canada and through simple observations. Preliminary findings indicated that time and environmental changes affected the detection of the porcine bodies by either being too dry and having too high a resistivity to survey effectively, or too wet and having the site flushed with water making the surrounding ground similar in resistivity to the bodies. Future research is needed to further explore how best to minimize environmental changes from resistivity results to enable reliable detection of buried organic material such as human remains In regard to array configurations, the square array in particular shows promise in that it can be set up and executed in less time than running several linear arrays over the same area. The application of such unconventional arrays to police forensic work may prove valuable if the area of interest is off-limits for resistivity surveys due to physical obstructions.

Baseline tests for arc melter vitrification of INEL buried wastes. Volume II: Baseline test data appendices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oden, L.L.; O`Conner, W.K.; Turner, P.C.

1993-11-19

This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc meltingmore » furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests.« less

Baseline tests for arc melter vitrification of INEL buried wastes. Volume 1: Facility description and summary data report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oden, L.L.; O`Connor, W.K.; Turner, P.C.

1993-11-19

This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc meltingmore » furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests.« less

Cathodic Protection Measurement Through Inline Inspection Technology Uses and Observations

NASA Astrophysics Data System (ADS)

Ferguson, Briana Ley

This research supports the evaluation of an impressed current cathodic protection (CP) system of a buried coated steel pipeline through alternative technology and methods, via an inline inspection device (ILI, CP ILI tool, or tool), in order to prevent and mitigate external corrosion. This thesis investigates the ability to measure the current density of a pipeline's CP system from inside of a pipeline rather than manually from outside, and then convert that CP ILI tool reading into a pipe-to-soil potential as required by regulations and standards. This was demonstrated through a mathematical model that utilizes applications of Ohm's Law, circuit concepts, and attenuation principles in order to match the results of the ILI sample data by varying parameters of the model (i.e., values for over potential and coating resistivity). This research has not been conducted previously in order to determine if the protected potential range can be achieved with respect to the predicted current density from the CP ILI device. Kirchhoff's method was explored, but certain principals could not be used in the model as manual measurements were required. This research was based on circuit concepts which indirectly affected electrochemical processes. Through Ohm's law, the results show that a constant current density is possible in the protected potential range; therefore, indicates polarization of the pipeline, which leads to calcareous deposit development with respect to electrochemistry. Calcareous deposit is desirable in industry since it increases the resistance of the pipeline coating and lowers current, thus slowing the oxygen diffusion process. This research conveys that an alternative method for CP evaluation from inside of the pipeline is possible where the pipe-to-soil potential can be estimated (as required by regulations) from the ILI tool's current density measurement.

Performance Evaluation and Modeling of Erosion Resistant Turbine Engine Thermal Barrier Coatings

NASA Technical Reports Server (NTRS)

Miller, Robert A.; Zhu, Dongming; Kuczmarski, Maria

2008-01-01

The erosion resistant turbine thermal barrier coating system is critical to the rotorcraft engine performance and durability. The objective of this work was to determine erosion resistance of advanced thermal barrier coating systems under simulated engine erosion and thermal gradient environments, thus validating a new thermal barrier coating turbine blade technology for future rotorcraft applications. A high velocity burner rig based erosion test approach was established and a new series of rare earth oxide- and TiO2/Ta2O5- alloyed, ZrO2-based low conductivity thermal barrier coatings were designed and processed. The low conductivity thermal barrier coating systems demonstrated significant improvements in the erosion resistance. A comprehensive model based on accumulated strain damage low cycle fatigue is formulated for blade erosion life prediction. The work is currently aiming at the simulated engine erosion testing of advanced thermal barrier coated turbine blades to establish and validate the coating life prediction models.

Impact of ALD Coating on Mn-rich Cathode Materials (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santhanagopalan, S.

2013-06-01

LG Chem Power Inc. (LGCPI) and NREL have collaborated to demonstrate the scalability of the atomic layer deposition (ALD) coating process over the last 6 months, and the benefits of ALD coatings for long-term cycling and calendar life are being quantified. The objectives of this work are two-fold: 1) to evaluate the scalability of the process to coat LGCPI cathodes with alumina using the ALD technique, and 2) to demonstrate improvements in rate capability and life of ALD-coated LGCPI electrodes. NREL received samples of baseline material to be coated from LGCPI. NREL carried out ALD coating of the samples withmore » help from a subcontractor, ALD Nanosolutions. NREL fabricated cells from those samples for quick screening and feedback to ALD Nanosolutions. LGCPI is currently fabricating larger-format cells for further evaluation.« less

75 FR 59933 - Specifications and Drawings for Construction of Direct Buried Plant

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-29

... for Construction of Direct Buried Plant AGENCY: Rural Utilities Service, USDA. ACTION: Final rule..., Specifications and Drawings for Construction of Direct Buried Plant (Form 515a). The revised specifications will include new construction units for Fiber-to-the-Home, remove redundant or outdated requirements, and...

Sensor Phenomenology and Feature Development for Improved Sonar-based Detection & Classification of Underwater UXO

DTIC Science & Technology

2009-12-01

the validity of approximating poroelastic media with acoustic or acoustic /elastic models , and to characterize how scattering physics will differ for...elastic buried object (yellow rectangle in the figure) in three types of environments: • (1) Model 1: acoustic layer on top of a poroelastic medium with a...porosity gradient and no viscous damping. • (2) Model 2: acoustic layer on top of a poroelastic medium with a porosity gradient and viscous damping

Method of sealing casings of subsurface materials management system

DOEpatents

Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

2007-02-06

Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

Structural Acoustic UXO Detection and Identification in Marine Environments

DTIC Science & Technology

2016-05-01

BOSS Buried Object Scanning Sonar DVL Doppler Velocity Log EW East/West IMU Inertial Measurement Unit NRL Naval Research Laboratory NSWC-PCD... Inertial Measurement Unit (IMU) to time-delay and coherently sum matched-filtered phase histories from subsurface focal points over a large number of... Measurement Unit (IMU) systems. In our imaging algorithm, the 2D depth image of a target, i.e. one mapped over x and z or y and z, presents the

Buried Target Imaging: A Comparative Study

NASA Astrophysics Data System (ADS)

Ghaderi Aram, Morteza; Dehmollaian, Mojtaba; Khaleghi, Ali

2017-12-01

A wide variety of qualitative methods have been proposed for microwave imaging. It is difficult to select only one of these methods based on a priori information and measurement equipment to achieve a reliable reconstruction. Various arrangements for antennas to be used in, for instance, have been proposed which have direct impacts on the complexity of inverse methods as well as the quality of output images. In this study, four qualitative methods of the linear sampling method (LSM), time reversal (TR), diffraction tomography (DT), and back-projection (BP) have been reviewed in a 2D scenario; the performance of the methods is compared within the same framework of a multi-static configuration. The goal is to compare their resolutions and determine their advantages and drawbacks. It is shown that LSM provides the best azimuth resolution but the worst range resolution. It is almost invariant to dielectric contrast and is appropriate for a wide range of dielectric contrasts and relatively large objects. It is also shown that at relatively low dielectric contrasts, TR images are most similar to the true object, show fewer artifacts, and offer high immunity to noise. While suffering from more artifacts due to the presence of some ghost images, DT offers the best range resolution. The results also show that BP has the worst azimuth resolution when reconstructing deeply-buried targets, although its implementation is straightforward and not computationally complex.

Vacuum plasma coatings for turbine blades

NASA Technical Reports Server (NTRS)

Holmes, R. R.

1985-01-01

Turbine blades, vacuum plasma spray coated with NiCrAlY, CoCrAlY or NiCrAlY/Cr2O3, were evaluated and rated superior to standard space shuttle main engine (SSME) coated blades. Ratings were based primarily on 25 thermal cycles in the MSFC Burner Rig Tester, cycling between 1700 F (gaseous H2) and -423 F (liquid H2). These tests showed no spalling on blades with improved vacuum plasma coatings, while standard blades spalled. Thermal barrier coatings of ZrO2, while superior to standard coatings, lacked the overall performance desired. Fatigue and tensile specimens, machined from MAR-M-246(Hf) test bars identical to the blades were vacuum plasma spray coated, diffusion bond treated, and tested to qualify the vacuum plasma spray process for flight hardware testing and application. While NiCrAlY/Cr2O3 offers significant improvement over standard coatings in durability and thermal protection, studies continue with an objective to develop coatings offering even greater improvements.

Effect assessment of "film coating and packaging" on the photo-stability of highly photo-labile antihypertensive products.

PubMed

Mukharya, Amit; Patel, Paresh U; Chaudhary, Shivang

2013-04-01

Lacidipine (LCDP) is chemically a "1, 4-dihydropyridine derivative" Ca+(2) channel blocker used as an antihypertensive. Type and extent of packaging have a strong influence on the photo-stability of the 1,4-dihydropyridine derivatives. In standard, light protection of drug substance/drug product can be obtained either by use of an opaque additive in the formulation that competitively absorbs or reflects light reaching the sample and/or by blocking the access of light to the drug through external protection by packaging. External protection by covering tablets with an opaque film coating involving a light-reflecting inorganic pigment such as titanium dioxide and/or by using an opaque impermeable packaging material was an appropriate suitable option for establishing photo-stability. Thus, the main objective of the present study was to optimize the % level of film coating in LCDP core tablets, and selection of a final packaging material and its respective extent, that is, primary, secondary and/or tertiary packaging, for LCDP tablets. The main objective (% level of film coating) was optimized by directly exposing core tablets, 1% w/w, 2% w/w and 3% w/w film-coated tablets, to a light source as per Option-2 of ICH Q1B and its comparative analysis at the end of light exposure testing. The other objective (extent of drug product packaging) was established successfully by assessing whether or not an acceptable change has occurred at the end of the light exposure testing of the LCDP film-coated tablets in a direct exposure study or a primary immediate pack and/or secondary marketing pack.

Effect assessment of “film coating and packaging” on the photo-stability of highly photo-labile antihypertensive products

PubMed Central

Mukharya, Amit; Patel, Paresh U; Chaudhary, Shivang

2013-01-01

Introduction: Lacidipine (LCDP) is chemically a “1, 4-dihydropyridine derivative” Ca+2 channel blocker used as an antihypertensive. Type and extent of packaging have a strong influence on the photo-stability of the 1,4-dihydropyridine derivatives. In standard, light protection of drug substance/drug product can be obtained either by use of an opaque additive in the formulation that competitively absorbs or reflects light reaching the sample and/or by blocking the access of light to the drug through external protection by packaging. Materials and Methods: External protection by covering tablets with an opaque film coating involving a light-reflecting inorganic pigment such as titanium dioxide and/or by using an opaque impermeable packaging material was an appropriate suitable option for establishing photo-stability. Thus, the main objective of the present study was to optimize the % level of film coating in LCDP core tablets, and selection of a final packaging material and its respective extent, that is, primary, secondary and/or tertiary packaging, for LCDP tablets. Results and Conclusion: The main objective (% level of film coating) was optimized by directly exposing core tablets, 1% w/w, 2% w/w and 3% w/w film-coated tablets, to a light source as per Option-2 of ICH Q1B and its comparative analysis at the end of light exposure testing. The other objective (extent of drug product packaging) was established successfully by assessing whether or not an acceptable change has occurred at the end of the light exposure testing of the LCDP film-coated tablets in a direct exposure study or a primary immediate pack and/or secondary marketing pack. PMID:24015379

INSTALLATION OF A 10-ELEMENT SHALLOW-BURIED ARRAY AT THE UINTA BASIN SEISMOLOGICAL OBSERVATORY, VERNAL, UTAH

DTIC Science & Technology

the array are buried to a depth of approximately 200 feet. This report outlines, in some detail, the installation of a buried array at the Uinta ... Basin Seismological Observatory. Major considerations in such an undertaking included the selection of the most effective array pattern and the most

ENVIRONMENTAL TECHNOLOGY VERIFICATION COATINGS AND COATING EQUIPMENT PROGRAM (ETV CCEP) HIGH TRANSFER EFFICIENCE SPRAY EQUIPMENT--GENERIC VERIFICATION PROTOCOL

EPA Science Inventory

The Environmental Technology Verification (ETV) Program has been established to verify the performance characteristics of innovative environmental technologies and report this objective information, thus, accelerating the entrance of these new technologies into the marketplace. V...

Corrosion protection service life of epoxy-coated reinforcing steel in Virginia bridge decks.

DOT National Transportation Integrated Search

2003-01-01

The corrosion protection service life extension provided by epoxy-coated reinforcement (ECR) was determined by comparing ECR and bare steel bars from 10 Virginia bridge decks built between 1981 and 1995. The objective was to determine the corrosion p...

Method of processing materials using an inductively coupled plasma

DOEpatents

Hull, Donald E.; Bieniewski, Thomas M.

1989-01-01

A method for coating surfaces or implanting ions in an object using an inductively coupled plasma. The method provides a gas-free environment, since the plasma is formed without using a gas. The coating material or implantation material is intitially in solid form.

Evaluation of Chitosan-Starch-Based Edible Coating To Improve the Shelf Life of Bod Ljong Cheese.

PubMed

Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

2015-07-01

The objective of this work was to evaluate the effectiveness of antimicrobial edible coatings to improve the quality of Bod ljong cheese throughout 25 days of storage. Coatings were prepared using chitosan, water chestnut starch, and glycerol as a base matrix, together with several combinations of antimicrobial substances: Cornus officinalis fruit extract (COFE), pine needle essential oil (PNEO), and nisin. Application of coating on cheese decreased water loss, lipid oxidation, changes in headspace gas composition, and color. Moreover, the edible coatings with COFE or PNEO had increased antimicrobial activity and did not permit growth of microorganisms. COFE and PNEO are manufactured from food-grade materials so they can be consumed as an integral part of the cheese, which represents a competitive advantage over nonedible coatings.

An evaluation of methods for identifying and interpreting buried soils in late Quaternary loess in Alaska: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1998

USGS Publications Warehouse

Muhs, Daniel R.; Ager, Thomas A.; Been, Josh M.; Rosenbaum, Joseph G.; Reynolds, Richard J.

2000-01-01

The presence of buried soils in Alaskan loess is controversial, and therefore criteria for identifying buried soils in these deposits need to be evaluated. In this paper, morphologic and chemical criteria for identifying buried soils are evaluated by studying modern soils developed mostly in Holocene loess under tundra, boreal forest, and transitional coastal-boreal forest vegetation in different parts of Alaska. Data from modern Alaskan soils that developed under vegetation similar to that of the present indicate that soil morphology, organic-matter concentrations, and P concentrations can be useful diagnostic tools for identifying buried soils. Soil morphologic criteria, particularly horizon colors and horizon sequences, are essential for identifying buried soils, but some minimally developed soils may resemble organic-rich alluvial, colluvial, or lacustrine deposits. Organic matter and total P contents and distributions can aid in such studies because in well-drained soils these constituents show rapid declines with depth. However, neither of these techniques may work if the upper genetic horizons of buried soils are eroded.If buried soils are present in Alaskan loess, it would also be desirable to have techniques for determining the dominant vegetation under which the soils formed. Such techniques could then be used to reconstruct former vegetation types and paleoclimates in Alaska. A previous study suggested that tundra and boreal forest vegetation have distinctive carbon isotopic compositions, although both are dominated by C3 plants. If this is the case, then the carbon isotopic composition of organic matter in buried soils could be used to reconstruct former vegetation types. A larger suite of modern soils from Alaskan tundra and forest were analyzed to test this hypothesis. Results indicate that modern soil O horizons in these two biomes have the same range of δ13C values, and therefore carbon isotope compositions cannot be used to reconstruct former tundra or boreal forest.

DBAC: A simple prediction method for protein binding hot spots based on burial levels and deeply buried atomic contacts

PubMed Central

2011-01-01

Background A protein binding hot spot is a cluster of residues in the interface that are energetically important for the binding of the protein with its interaction partner. Identifying protein binding hot spots can give useful information to protein engineering and drug design, and can also deepen our understanding of protein-protein interaction. These residues are usually buried inside the interface with very low solvent accessible surface area (SASA). Thus SASA is widely used as an outstanding feature in hot spot prediction by many computational methods. However, SASA is not capable of distinguishing slightly buried residues, of which most are non hot spots, and deeply buried ones that are usually inside a hot spot. Results We propose a new descriptor called “burial level” for characterizing residues, atoms and atomic contacts. Specifically, burial level captures the depth the residues are buried. We identify different kinds of deeply buried atomic contacts (DBAC) at different burial levels that are directly broken in alanine substitution. We use their numbers as input for SVM to classify between hot spot or non hot spot residues. We achieve F measure of 0.6237 under the leave-one-out cross-validation on a data set containing 258 mutations. This performance is better than other computational methods. Conclusions Our results show that hot spot residues tend to be deeply buried in the interface, not just having a low SASA value. This indicates that a high burial level is not only a necessary but also a more sufficient condition than a low SASA for a residue to be a hot spot residue. We find that those deeply buried atoms become increasingly more important when their burial levels rise up. This work also confirms the contribution of deeply buried interfacial atomic contacts to the energy of protein binding hot spot. PMID:21689480

NASA TEERM Hexavalent Chrome Alternatives Projects

NASA Technical Reports Server (NTRS)

Kessel, Kurt R.; Rothgeb, Matthew

2011-01-01

The overall objective of the Hex Chrome Free Coatings for Electronics project is to evaluate and test pretreatment coating systems not containing hexavalent chrome in avionics and electronics housing applications. This objective will be accomplished by testing strong performing coating systems from prior NASA and DoD testing or new coating systems as determined by the stakeholders. The technical stakeholders have agreed that this protocol will focus specifically on Class 3 coatings. Original Equipment Manufacturers (OEMs), depots, and support contractors have to be prepared to deal with an electronics supply chain that increasingly provides parts with lead-free finishes, some labeled no differently and intermingled with their SnPb counterparts. Allowance of lead-free components presents one of the greatest risks to the reliability of military and aerospace electronics. The introduction of components with lead-free terminations, termination finishes, or circuit boards presents a host of concerns to customers, suppliers, and maintainers of aerospace and military electronic systems such as: 1. Electrical shorting due to tin whiskers 2. Incompatibility of lead-free processes and parameters (including higher melting points of lead-free alloys) with other materials in the system 3. Unknown material properties and incompatibilities that could reduce solder joint reliability

Computational homogenisation for thermoviscoplasticity: application to thermally sprayed coatings

NASA Astrophysics Data System (ADS)

Berthelsen, Rolf; Denzer, Ralf; Oppermann, Philip; Menzel, Andreas

2017-11-01

Metal forming processes require wear-resistant tool surfaces in order to ensure a long life cycle of the expensive tools together with a constant high quality of the produced components. Thermal spraying is a relatively widely applied coating technique for the deposit of wear protection coatings. During these coating processes, heterogeneous coatings are deployed at high temperatures followed by quenching where residual stresses occur which strongly influence the performance of the coated tools. The objective of this article is to discuss and apply a thermo-mechanically coupled simulation framework which captures the heterogeneity of the deposited coating material. Therefore, a two-scale finite element framework for the solution of nonlinear thermo-mechanically coupled problems is elaborated and applied to the simulation of thermoviscoplastic material behaviour including nonlinear thermal softening in a geometrically linearised setting. The finite element framework and material model is demonstrated by means of numerical examples.

Apparatus and method for pulsed laser deposition of materials on wires and pipes

DOEpatents

Fernandez, Felix E.

2003-01-01

Methods and apparatuses are disclosed which allow uniform coatings to be applied by pulsed laser deposition (PLD) on inner and outer surfaces of cylindrical objects, such as rods, pipes, tubes, and wires. The use of PLD makes this technique particularly suitable for complex multicomponent materials, such as superconducting ceramics. Rigid objects of any length, i.e., pipes up to a few meters, and with diameters from less than 1 centimeter to over 10 centimeters can be coated using this technique. Further, deposition is effected simultaneously onto an annular region of the pipe wall. This particular arrangement simplifies the apparatus, reduces film uniformity control difficulties, and can result in faster operation cycles. In addition, flexible wires of any length can be continuously coated using the disclosed invention.

Environmental Technology Verification Coatings and Coating Equipment Program (ETV CCEP) High Transfer Efficiency Spray Equipment--Generic Verification Protocol

EPA Science Inventory

The Environmental Technology Verification (ETV) Program has been established by the U.S. Environmental Protection Agency (EPA) to verify the performance characteristics of innovative environmental technologies across all media and report this objective information to the states, ...

Aqueous Polymer Dispersion Coating Used for Osmotic Pump Tablets: Membrane Property Investigation and IVIVC Evaluation.

PubMed

Cheng, Lizhen; Gai, Xiumei; Wen, Haoyang; Liu, Dandan; Tang, Xin; Wang, Yanyan; Wang, Tuanjie; Pan, Weisan; Yang, Xinggang

2018-01-01

The objective of this study was to investigate the fundamental properties of propranolol hydrochloride osmotic pump tablets coated by aqueous polymer dispersion, simultaneously exploring the in vitro and in vivo correlation of the tablet. The physicochemical properties and parameters of aqueous polymer dispersion membranes (SEM, water uptake, and water vapor transmission coefficient) were investigated. In addition, the release behavior and the in vitro release and in vivo absorption profiles of the tablets coated by aqueous polymer dispersion were investigated by comparing with propranolol hydrochloride osmotic pump tablets coated by an organic solvent. Results showed that the similarity factor (f 2 ) between cellulose acetate-coated tablet and Eudragit-coated tablet was 78.1, and f 2 between cellulose acetate-coated tablet and Kollicoat-coated tablet was 77.6. The linear IVIVC of Eudragit-coated and Kollicoat-coated osmotic pump tablets was determined, which confirmed excellent correlation between the absorption in vivo and the drug release in vitro. Consequently, the membrane coated by aqueous polymer dispersion or organic solvent has similar in vitro release rates of controlled release. Also, compared with organic solvent coating, aqueous polymer dispersion has numerous advantages, such as reduced toxicity and no environmental damage. Therefore, the aqueous polymer dispersion technology has enormous potential as a replacement of organic solvent coating.

Development of an improved coating for polybenzimidazole foam. [for space shuttle heat shields

NASA Technical Reports Server (NTRS)

Neuner, G. J.; Delano, C. B.

1976-01-01

An improved coating system was developed for Polybenzimidazole (PBI) foam to provide coating stability, ruggedness, moisture resistance, and to satisfy optical property requirements (alpha sub (s/epsilon) or = 0.4 and epsilon 0.8) for the space shuttle. The effort was performed in five tasks: Task 1 to establish material and process specifications for the PBI foam, and material specifications for the coatings; Task 2 to identify and evaluate promising coatings; Task 3 to establish mechanical and thermophysical properties of the tile components; Task 4 to determine by systems analysis the potential weight trade-offs associated with a coated PBI TPS; and Task 5 to establish a preliminary quality assurance program. The coated PBI tile was, through screening tests, determined to satisfy the design objectives with a reduced system weight over the baseline shuttle silica LRSI TPS. The developed tile provides a thermally stable, extremely rugged, low thermal conductivity insulator with a well characterized optical coating.

Sound Science: Taking Action with Acoustics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinha, Dipen

2014-07-16

From tin whistles to sonic booms, sound waves interact with each other and with the medium through which they travel. By observing these interactions, we can identify substances that are hidden in sealed containers and obtain images of buried objects. By manipulating the ability of sound to push matter around, we can create novel structures and unique materials. Join the Lab's own sound hound, Dipen Sinha, as he describes how he uses fundamental research in acoustics for solving problems in industry, security and health.

Non-traditional Physics-based Inverse Approaches for Determining a Buried Object’s Location

DTIC Science & Technology

2008-09-01

parameterization of its time-decay curve) in dipole models ( Pasion and Oldenburg, 2001) or the amplitudes of responding magnetic sources in the NSMS...commonly in use. According to the simple dipole model ( Pasion and Oldenburg, 2001), the secondary magnetic field due to the dipole m is 3 0 1 ˆ ˆ(3...Forum, St. Louis, MO. L. R. Pasion and D. W. Oldenburg (2001), “A discrimination algorithm for UXO using time domain electromagnetics.” J. Environ

Sound Science: Taking Action with Acoustics

ScienceCinema

Sinha, Dipen

2018-01-16

From tin whistles to sonic booms, sound waves interact with each other and with the medium through which they travel. By observing these interactions, we can identify substances that are hidden in sealed containers and obtain images of buried objects. By manipulating the ability of sound to push matter around, we can create novel structures and unique materials. Join the Lab's own sound hound, Dipen Sinha, as he describes how he uses fundamental research in acoustics for solving problems in industry, security and health.

Subsurface materials management and containment system, components thereof and methods relating thereto

DOEpatents

Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

2006-04-18

Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

Surface characterization of an energetic material, pentaerythritoltetranitrate (PETN), having a thin coating achieved through a starved addition microencapsulation technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Worley, C.M.

The objective of this research was to: (1) determine the nature of a thin coating on an explosive material which was applied using a starved addition microencapsulation technique, (2) understand the coating/crystal bond, and (3) investigate the wettability/adhesion of plastic/solvent combinations using the coating process. The coating used in this work was a Firestone Plastic Company copolymer (FPC-461) of vinylchloride/trifluorochloroethylene in a 1.5/1.0 weight ratio. The energetic explosive examined was pentaerythritoltetranitrate (PETN). The coating process used was starved addition followed by a solvent evaporation technique. Surface analytical studies, completed for characterization of the coating process, show (1) evidence that themore » polymer coating is present, but not continuous, over the surface of PETN; (2) the average thickness of the polymer coating is between 16-32 A and greater than 44 A, respectively, for 0.5 and 20 wt % coated PETN; (3) no changes in surface chemistry of the polymer or the explosive material following microencapsulation; and (4) the presence of explosive material on the surface of 0.5 wt % FPC-461 coated explosives. 5 refs., 15 figs., 6 tabs.« less

Modelling the buried human body environment in upland climes using three contrasting field sites.

PubMed

Wilson, Andrew S; Janaway, Robert C; Holland, Andrew D; Dodson, Hilary I; Baran, Eve; Pollard, A Mark; Tobin, Desmond J

2007-06-14

Despite an increasing literature on the decomposition of human remains, whether buried or exposed, it is important to recognise the role of specific microenvironments which can either trigger or delay the rate of decomposition. Recent casework in Northern England involving buried and partially buried human remains has demonstrated a need for a more detailed understanding of the effect of contrasting site conditions on cadaver decomposition and on the microenvironment created within the grave itself. Pigs (Sus scrofa) were used as body analogues in three inter-related taphonomy experiments to examine differential decomposition of buried human remains. They were buried at three contrasting field sites (pasture, moorland, and deciduous woodland) within a 15 km radius of the University of Bradford, West Yorkshire, UK. Changes to the buried body and the effect of these changes on hair and associated death-scene textile materials were monitored as was the microenvironment of the grave. At recovery, 6, 12 and 24 months post-burial, the extent of soft tissue decomposition was recorded and samples of fat and soil were collected for gas chromatography mass spectrometry (GCMS) analysis. The results of these studies demonstrated that (1) soil conditions at these three burial sites has a marked effect on the condition of the buried body but even within a single site variation can occur; (2) the process of soft tissue decomposition modifies the localised burial microenvironment in terms of microbiological load, pH, moisture and changes in redox status. These observations have widespread application for the investigation of clandestine burial and time since deposition, and in understanding changes within the burial microenvironment that may impact on biomaterials such as hair and other associated death scene materials.

Martian Buried Basins and Implications for Characteristics of the Burial Layer and Underlying Surface

NASA Technical Reports Server (NTRS)

Sarid, A. R.; Frey, H. V.; Roark, J. H.

2003-01-01

Deciphering the cratering record on Mars has been challenging because it may reflect the changes in both the population of impactors and in the resurfacing processes on Mars. However, it is possible to determine the breadth of impactors captured in the cratering record. Extensive areas of resurfacing are of particular interest because they likely contain material from various ages in Martian history. By deducing the impact populations in both surface and underlying layers of terrain, it is possible to determine the age of the layers and constrain theories on the development of the Martian surface. However, to do so requires a method of seeing impact features which are no longer visible. Topographic data of Mars, taken by the Mars Orbiter Laser Altimeter (MOLA), has revealed impact features buried by resurfacing processes. These features are often indistinguishable on Viking images of the Martian surface. In this study, gridded MOLA data was analyzed in order to locate buried impact features, also called buried basins, in Syria, Solis, and Sinai Planum just south of Valles Marineris. The population statistics of buried features can be compared to those of visible features in order to determine the age of the underlying material and characteristics of the surface cover. Specifically, if the buried population in the Hesperian terrain is similar to the population of visible features in the Noachian, it would suggest that the underlying terrain is Noachian in age. The buried craters can then be compared to visible Noachian craters to reveal the amount of deterioration of the buried features. These comparisons allow us to explore the morphology of the terrain in the Hesperian region to determine if topographic variations are due to differences in the thickness of the overlying material or are a characteristic of the underlying terrain.

Influences of Processing and Fatigue Cycling on Residual Stresses in a NiCrY-Coated Powder Metallurgy Disk Superalloy

NASA Astrophysics Data System (ADS)

Gabb, T. P.; Rogers, R. B.; Nesbitt, J. A.; Miller, R. A.; Puleo, B. J.; Johnson, D.; Telesman, J.; Draper, S. L.; Locci, I. E.

2017-11-01

Oxidation and corrosion can attack superalloy disk surfaces exposed to increasing operating temperatures in some turbine engine environments. Any potential protective coatings must also be resistant to harmful fatigue cracking during service. The objective of this study was to investigate how residual stresses evolve in one such coating. Fatigue specimens of a powder metallurgy-processed disk superalloy were coated with a NiCrY coating, shot peened, and then subjected to fatigue in air at room and high temperatures. The effects of this processing and fatigue cycling on axial residual stresses and other aspects of the coating were assessed. While shot peening did induce beneficial compressive residual stresses in the coating and substrate, these stresses relaxed in the coating with subsequent heating. Several cast alloys having compositions near the coating were subjected to thermal expansion and tensile stress relaxation tests to help explain this response of residual stresses in the coating. For the coated fatigue specimens, this response contributed to earlier cracking of the coating than for the uncoated surface during long intervals of cycling at 760 °C. Yet, substantial compressive residual stresses still remained in the substrate adjacent to the coating, which were sufficient to suppress fatigue cracking there. The coating continued to protect the substrate from hot corrosion pitting, even after fatigue cracks initiated in the coating.

Fabrication of SOI structures with buried cavities using Si wafer direct bonding and electrochemical etch-stop

NASA Astrophysics Data System (ADS)

Chung, Gwiy-Sang

2003-10-01

This paper describes the fabrication of SOI structures with buried cavities using SDB and electrochemical etch-stop. These methods are suitable for thick membrane fabrication with accurate thickness, uniformity, and flatness. After a feed-through hole for supplied voltage and buried cavities was formed on a handle Si wafer with p-type, the handle wafer was bonded to an active Si wafer consisting of a p-type substrate with an n-type epitaxial layer corresponding to membrane thickness. The bonded pair was then thinned until electrochemical etch-stop occurred at the pn junction during electrochemical etchback. By using the SDB SOI structure with buried cavities, active membranes, which have a free standing structure with a dimension of 900×900 μm2, were fabricated. It is confirmed that the fabrication process of the SDB SOI structure with buried cavities is a powerful and versatile technology for new MEMS applications.

IODP Expedition 337: Deep Coalbed Biosphere off Shimokita - Microbial processes and hydrocarbon system associated with deeply buried coalbed in the ocean

NASA Astrophysics Data System (ADS)

Inagaki, Fumio; Hinrichs, Kai-Uwe; Kubo, Yusuke; IODP Expedition 337 Scientists

2016-06-01

The Integrated Ocean Drilling Program (IODP) Expedition 337 was the first expedition dedicated to subseafloor microbiology that used riser-drilling technology with the drilling vessel Chikyu. The drilling Site C0020 is located in a forearc basin formed by the subduction of the Pacific Plate off the Shimokita Peninsula, Japan, at a water depth of 1180 m. Primary scientific objectives during Expedition 337 were to study the relationship between the deep microbial biosphere and a series of ˜ 2 km deep subseafloor coalbeds and to explore the limits of life in the deepest horizons ever probed by scientific ocean drilling. To address these scientific objectives, we penetrated a 2.466 km deep sedimentary sequence with a series of lignite layers buried around 2 km below the seafloor. The cored sediments, as well as cuttings and logging data, showed a record of dynamically changing depositional environments in the former forearc basin off the Shimokita Peninsula during the late Oligocene and Miocene, ranging from warm-temperate coastal backswamps to a cool water continental shelf. The occurrence of small microbial populations and their methanogenic activity were confirmed down to the bottom of the hole by microbiological and biogeochemical analyses. The factors controlling the size and viability of ultra-deep microbial communities in those warm sedimentary habitats could be the increase in demand of energy and water expended on the enzymatic repair of biomolecules as a function of the burial depth. Expedition 337 provided a test ground for the use of riser-drilling technology to address geobiological and biogeochemical objectives and was therefore a crucial step toward the next phase of deep scientific ocean drilling.

TEXTURE PROFILES OF PEANUT PASTES ENHANCED WITH PEANUT SEED COATS

USDA-ARS?s Scientific Manuscript database

Peanut paste is commonly used by food manufacturers because it provides a unique flavor, good nutrient content and a smooth, creamy texture. Nutritional properties of peanut paste can be improved by the addition of peanut seed coats which are currently of little value. The objective of this research...

DELAMINATION AND XRF ANALYSIS OF NIST LEAD IN PAINT FILM STANDARDS

EPA Science Inventory

The objectives of this protocol were to remove the laminate coating from lead paint film standards acquired from NIST by means of surface heating. The average XRF value did not change after removal of the polymer coating suggesting that this protocol is satisfactory for renderin...

Identification of a single gene for seed coat impermeability in soybean PI 594619

USDA-ARS?s Scientific Manuscript database

High temperatures during seed fill increase the occurrence of soybeans with impermeable seed coat, which is associated with non-uniform and delayed germination and emergence. This has become an issue in soybean production areas with excessively high-temperature environments. The objectives of the pr...

Experimental concrete coating application on the median barrier of I 65 in Louisville.

DOT National Transportation Integrated Search

2008-06-01

The objectives of this research were to evaluate the experimental protective coating that was applied to approximately 1,200 linear feet of concrete median barrier along the paving project on a section of I 65 between mile points 131.289 and 136.421 ...

Mechanical and wear properties of aluminum coating prepared by cold spraying

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yusof, Siti Nurul Akmal, E-mail: em-leo277@yahoo.com; Manap, Abreeza, E-mail: Abreeza@uniten.edu.my; Afandi, Nurfanizan Mohd

In this study, aluminum (Al) powders were deposited onto Al substrates using cold spray to form a coating. The main objective is to investigate and compare the microstructure, mechanical and wear properties of Al coating to that of the Al substrate. The microstructure of the coating and substrate were observed using Scanning Electron Microscope (SEM). Hardness was evaluated using the Vickers Hardness test and wear properties were investigated using a pin-on-disk wear test machine. The elemental composition of the coating and substrate was determined using Energy-dispersive X-ray spectroscopy (EDX). Results showed that the friction coefficient and specific wear rate decreasedmore » while wear rate increased linearly with increasing load. It was found that the coating exhibit slightly better mechanical and wear properties compared to the substrate.« less

Experimental evaluation of chromium-carbide-based solid lubricant coatings for use to 760 C

NASA Technical Reports Server (NTRS)

Dellacorte, Christopher

1987-01-01

A research program is described which further developed and investigated chromium carbide based self-lubricating coatings for use to 760 C. A bonded chromium carbide was used as the base stock because of the known excellent wear resistance and the chemical stability of chromium carbide. Additives were silver and barium fluoride/calcium fluoride eutectic. The three coating components were blended in powder form, applied to stainless steel substrates by plasma spraying and then diamond ground to the desired coating thickness. A variety of coating compositions was tested to determine the coating composition which gave optimum tribological results. Coatings were tested in air, helium, and hydrogen at temperatures from 25 to 760 C. Several counterface materials were evaluated with the objective of discovering a satisfactory metal/coating sliding combination for potential applications, such as piston ring/cylinder liner couples for Stirling engines. In general, silver and fluoride additions to chromium carbide reduced the friction coefficient and increased the wear resistance relative to the unmodified coating. The lubricant additives acted synergistically in reducing friction and wear.

Simulation and evaluation of rupturable coated capsules by finite element method.

PubMed

Yang, Yan; Fang, Jie; Shen, Lian; Shan, Weiguang

2017-03-15

The objective of this study was to simulate and evaluate the burst behavior of rupturable coated capsules by finite element method (FEM). Film and coated capsules were prepared by dip-coating method and their dimensions were determined by stereomicroscope. Mechanical properties of the film were measured by tensile test and used as material properties of FEM models. Swelling pressure was determined by restrained expansion method and applied to the internal surface of FEM models. Water uptake of coated capsules was determined to study the formation of internal pressure. Burst test and in vitro dissolution was used to verify the FEM models, which were used to study and predict the coating burst behavior. Simulated results of coating burst behavior were well agreed with the experiment results. Swelling pressure, material properties and dimensions of coating had influence on the maximum stress. Burst pressure and critical L-HPC content were calculated for burst prediction and formulation optimization. FEM simulation was a feasible way to simulate and evaluate the burst behavior of coated capsules. Copyright © 2017 Elsevier B.V. All rights reserved.

Whole-field digital vibrometer system for buried landmine detection

NASA Astrophysics Data System (ADS)

Lal, Amit; Hess, Cecil; Scott, Eddie; Dang, Michael; Nichols, Robert

2005-06-01

Previous results have shown the potential of acoustic-to-seismic coupling with Laser Doppler Vibrometry for the detection of buried landmines. An important objective of the present technology is to improve the spatial resolution and the speed of the measurement. In this paper, MetroLaser reports on a whole-field digital vibrometer (WDV) that measures an entire one meter area with sub-centimeter spatial resolution in just a few seconds. The WDV is based on a dual-pulsed laser such that each pulse illuminates a one meter area on the ground, and the temporal separation between the two laser pulses can be adjusted to match the ground excitation frequency. By sweeping this excitation frequency, a displacement map of the ground at each frequency can be quickly generated. In addition, an innovative speckle repositioning strategy allows for movement of the measurement platform at reasonable speeds while still obtaining measurements with interferometric precision. This paper describes the WDV instrument and presents preliminary experimental results obtained with this system. This research is being supported by the U.S. Army RDECOM CERDEC NVESD under Contract W909MY04-C-0004.

Estimation of Gravity Parameters Related to Simple Geometrical Structures by Developing an Approach Based on Deconvolution and Linear Optimization Techniques

NASA Astrophysics Data System (ADS)

Asfahani, J.; Tlas, M.

2015-10-01

An easy and practical method for interpreting residual gravity anomalies due to simple geometrically shaped models such as cylinders and spheres has been proposed in this paper. This proposed method is based on both the deconvolution technique and the simplex algorithm for linear optimization to most effectively estimate the model parameters, e.g., the depth from the surface to the center of a buried structure (sphere or horizontal cylinder) or the depth from the surface to the top of a buried object (vertical cylinder), and the amplitude coefficient from the residual gravity anomaly profile. The method was tested on synthetic data sets corrupted by different white Gaussian random noise levels to demonstrate the capability and reliability of the method. The results acquired show that the estimated parameter values derived by this proposed method are close to the assumed true parameter values. The validity of this method is also demonstrated using real field residual gravity anomalies from Cuba and Sweden. Comparable and acceptable agreement is shown between the results derived by this method and those derived from real field data.

Commercial-Off-the-Shelf (COTS), Volatile Organic Compounds (VOCs) and Hazardous Air Pollutants (HAPs)-Free, Non-Chromate Low Temperature Powder Coating (LTPC) System for United States Air Force use (PHASE II )

DTIC Science & Technology

2017-09-12

and Hazardous Air Pollutants (HAPs)-Free, non -chromate low temperature powder coating (LTPC) system for United States Air Force use PHASE II PR...required to support and successfully complete this effort. 1.1 Objective(s). The Contractor shall be required to demonstrate a non -chromate...5.0 General Information 5.1 Continuation of Mission-Essential Services During a Crisis. The Functional Commander (FC) or civilian equivalent has

The study of buried drift aquifers in Minnesota by seismic geophysical methods

USGS Publications Warehouse

Woodward, D. G.

1984-01-01

Buried-drift aquifers are stratified sand and (or) gravel aquifers in glacial deposits that cannot be seen or inferred at the land surface. During the Pleistocene Epoch, four continental glaciations advanced and retreated across Minnesota, blanketing the bedrock surface with drift as much as 700 feet thick (fig. 1). Most of the drift consists of till, an unsorted, un-stratified mixture of clay silt, sand, and gravel that usually is not considered to be an aquifer. Permeable, stratified sand and gravel, deposited as outwash, alluvium, and (or) ice-contact deposits usually during an earlier glacial episode and subsequently covered (buried) with till, form the buried-drift aquifers.

Viking Lander's Buried Footpad #3

NASA Technical Reports Server (NTRS)

1976-01-01

One of Viking l's three feet, which should be visible in this view, lies buried beneath a cover of loose Martian soil. This picture, taken Sunday (August 1), is the first to show the buried footpad #3. If not buried, the edge of the foot would be seen extending across the picture about midway between top and bottom. The foot sank about five inches, and fine-grained soil slumped into the depression and over the foot. The cracked nature of the surface near the slump area and the small, steep cliff at left indicates that the material is weakly cohesive. The surface material here is very similar mechanically to lunar soil.

Concealed epispadias associated with a buried penis.

PubMed

Sol Melgar, Ricardo; Gorduza, Daniela; Demède, Delphine; Mouriquand, Pierre

2016-12-01

The aim was to describe the clinical presentation and the surgical management of penile epispadias associated with a buried penis in five children. This is a 5-year retrospective review of patients presenting with a buried penis, a congenital defect of the penile skin shaft associated with an unretractable foreskin for whom a penile epispadias was found at the time of surgery. All had undergone surgery combining a Cantwell-Ransley procedure and refashioning of the penile skin following the authors' technique. Three children had a glanular epispadias and two had a midshaft epispadias. Four had a satisfactory outcome, and one required a complementary urethroplasty for glanular dehiscence. Buried penis and epispadias are usually isolated congenital anomalies, although they can be associated. It is therefore recommended to warn parents about the possibility of underlying penile anomaly in children with buried penises and unretractable foreskin. Careful palpation of the dorsum of the glans through the foreskin looking for a dorsal cleft could indicate an associated epispadiac urethra. Surgical correction of both anomalies can be done at the same time. Parents of boys with buried penises should be warned that underlying penile anomaly may exist. Copyright © 2016 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Finding buried metallic pipes using a non-destructive approach based on 3D time-domain induced polarization data

NASA Astrophysics Data System (ADS)

Shao, Zhenlu; Revil, André; Mao, Deqiang; Wang, Deming

2018-04-01

The location of buried utility pipes is often unknown. We use the time-domain induced polarization method to non-intrusively localize metallic pipes. A new approach, based on injecting a primary electrical current between a pair of electrodes and measuring the time-lapse voltage response on a set of potential electrodes after shutting down this primary current is used. The secondary voltage is measured on all the electrodes with respect to a single electrode used as a reference for the electrical potential, in a way similar to a self-potential time lapse survey. This secondary voltage is due to the formation of a secondary current density in the ground associated with the polarization of the metallic pipes. An algorithm is designed to localize the metallic object using the secondary voltage distribution by performing a tomography of the secondary source current density associated with the polarization of the pipes. This algorithm is first benchmarked on a synthetic case. Then, two laboratory sandbox experiments are performed with buried metallic pipes located in a sandbox filled with some clean sand. In Experiment #1, we use a horizontal copper pipe while in Experiment #2 we use an inclined stainless steel pipe. The result shows that the method is effective in localizing these two pipes. At the opposite, electrical resistivity tomography is not effective in localizing the pipes because they may appear resistive at low frequencies. This is due to the polarization of the metallic pipes which blocks the charge carriers at its external boundaries.

Problems of Military Cemeteries Greenery - Case Study of the Military Cemetery in Zvolen

NASA Astrophysics Data System (ADS)

Halajová, Denisa; Petreková, Denisa; Bihuňová, Mária

2017-10-01

The intention of this work is to highlight the importance of understanding military cemeteries as objects of cultural and historical heritage and as a part of garden design history. The design and maintenance of cemeteries and graves is a manifestation of the national culture. This is even more evident in military cemeteries, the maintenance of which is regulated by international agreements. Objects of military cemeteries are important places not only from the historical and architectural point of view, but also as green space. Most military cemeteries in Slovakia originated from World War I and II. In Slovakia, 160,000 soldiers were buried, 75,206 of them lost their lives in World War I and 93,000 in World War II. 32,495 war graves are registered by The Ministry of the Interior of the Slovak Republic - 23,316 war graves from World War I and 9,179 from World War II. From the period of World War II, there are 22 cemeteries and graveyards in Slovakia, established for soldiers of the Soviet, German, Romanian and Czechoslovak army. Military cemeteries and memorials are mostly high quality works of architecture and art. This paper focuses on the current situation and restoration issues of military cemeteries by examining the Military Cemetery in Zvolen. In the context of its planned reconstruction, a comprehensive tree assessment has been started in 2016. The Military Cemetery in Zvolen, being one of the largest military cemeteries in Slovakia, consists of The Cemetery of the Soviet Army with 17,628 buried soldiers and The Romanian Cemetery with 11,000 buried soldiers. The Romanian Cemetery is one of the largest cemeteries of the Romanian Army in Europe. Both cemeteries were declared national cultural monuments in 1963. In the cemetery, dendrometrical parameters and the health condition of trees were evaluated. In total, there are 825 woody plants. In both cemeteries, coniferous trees prevail, mainly individuals of the genus Thuja (49.4 %). Moreover, the maintenance of greenery and the aesthetics of the landscape composition were assessed. Based on the assessment of woody plant species composition, health condition of trees and their aesthetic qualities, necessary changes in the cemetery landscape composition were designed.

Detection capability of a pulsed Ground Penetrating Radar utilizing an oscilloscope and Radargram Fusion Approach for optimal signal quality

NASA Astrophysics Data System (ADS)

Seyfried, Daniel; Schoebel, Joerg

2015-07-01

In scientific research pulsed radars often employ a digital oscilloscope as sampling unit. The sensitivity of an oscilloscope is determined in general by means of the number of digits of its analog-to-digital converter and the selected full scale vertical setting, i.e., the maximal voltage range displayed. Furthermore oversampling or averaging of the input signal may increase the effective number of digits, hence the sensitivity. Especially for Ground Penetrating Radar applications high sensitivity of the radar system is demanded since reflection amplitudes of buried objects are strongly attenuated in ground. Hence, in order to achieve high detection capability this parameter is one of the most crucial ones. In this paper we analyze the detection capability of our pulsed radar system utilizing a Rohde & Schwarz RTO 1024 oscilloscope as sampling unit for Ground Penetrating Radar applications, such as detection of pipes and cables in the ground. Also effects of averaging and low-noise amplification of the received signal prior to sampling are investigated by means of an appropriate laboratory setup. To underline our findings we then present real-world radar measurements performed on our GPR test site, where we have buried pipes and cables of different types and materials in different depths. The results illustrate the requirement for proper choice of the settings of the oscilloscope for optimal data recording. However, as we show, displaying both strong signal contributions due to e.g., antenna cross-talk and direct ground bounce reflection as well as weak reflections from objects buried deeper in ground requires opposing trends for the oscilloscope's settings. We therefore present our Radargram Fusion Approach. By means of this approach multiple radargrams recorded in parallel, each with an individual optimized setting for a certain type of contribution, can be fused in an appropriate way in order to finally achieve a single radargram which displays all contributions occurring originally at different strengths in an equalized and normalized way by means of appropriate digital signal post-processing.

Ultrasonic/Sonic Impacting Penetrators

NASA Technical Reports Server (NTRS)

Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Stark, Randall A.

2008-01-01

Ultrasonic/sonic impacting penetrators (USIPs) are recent additions to the series of apparatuses based on ultrasonic/sonic drill corers (USDCs). A USIP enables a rod probe to penetrate packed soil or another substance of similar consistency, without need to apply a large axial force that could result in buckling of the probe or in damage to some buried objects. USIPs were conceived for use in probing and analyzing soil to depths of tens of centimeters in the vicinity of buried barrels containing toxic waste, without causing rupture of the barrels. USIPs could also be used for other purposes, including, for example, searching for pipes, barrels, or other hard objects buried in soil; and detecting land mines. USDCs and other apparatuses based on USDCs have been described in numerous previous NASA Tech Briefs articles. The ones reported previously were designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. To recapitulate: A USDC can be characterized as a lightweight, low-power, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. As shown in the figure, a basic USDC includes a piezoelectric stack, a backing and a horn connected to the stack, a free mass (free in the sense that it can slide axially a short distance between the horn and the shoulder of tool bit), and a tool bit, i.e., probe for USIP. The piezoelectric stack is driven at the resonance frequency of the stack/horn/backing assembly to create ultrasonic vibrations that are mechanically amplified by the horn. To prevent fracture during operation, the piezoelectric stack is held in compression by a bolt. The bouncing of the free mass between the horn and the tool bit at sonic frequencies generates hammering actions to the bit that are more effective for drilling than is the microhammering action of ultrasonic vibrations in ordinary ultrasonic drills. The hammering actions are so effective that the axial force needed to make the tool bit advance into the material of interest is much smaller than in ordinary twist drilling, ultrasonic drilling, or ordinary steady pushing.

Thermal barrier coating life prediction model

NASA Technical Reports Server (NTRS)

Hillery, R. V.; Pilsner, B. H.

1985-01-01

This is the first report of the first phase of a 3-year program. Its objectives are to determine the predominant modes of degradation of a plasma sprayed thermal barrier coating system, then to develop and verify life prediction models accounting for these degradation modes. The first task (Task I) is to determine the major failure mechanisms. Presently, bond coat oxidation and bond coat creep are being evaluated as potential TBC failure mechanisms. The baseline TBC system consists of an air plasma sprayed ZrO2-Y2O3 top coat, a low pressure plasma sprayed NiCrAlY bond coat, and a Rene'80 substrate. Pre-exposures in air and argon combined with thermal cycle tests in air and argon are being utilized to evaluate bond coat oxidation as a failure mechanism. Unexpectedly, the specimens pre-exposed in argon failed before the specimens pre-exposed in air in subsequent thermal cycles testing in air. Four bond coats with different creep strengths are being utilized to evaluate the effect of bond coat creep on TBC degradation. These bond coats received an aluminide overcoat prior to application of the top coat to reduce the differences in bond coat oxidation behavior. Thermal cycle testing has been initiated. Methods have been selected for measuring tensile strength, Poisson's ratio, dynamic modulus and coefficient of thermal expansion both of the bond coat and top coat layers.

Advanced ceramic coating development for industrial/utility gas turbines

NASA Technical Reports Server (NTRS)

Vogan, J. W.; Stetson, A. R.

1982-01-01

A program was conducted with the objective of developing advanced thermal barrier coating (TBC) systems. Coating application was by plasma spray. Duplex, triplex and graded coatings were tested. Coating systems incorporated both NiCrAly and CoCrAly bond coats. Four ceramic overlays were tested: ZrO2.82O3; CaO.TiO2; 2CaO.SiO2; and MgO.Al2O3. The best overall results were obtained with a CaO.TiO2 coating applied to a NiCrAly bond coat. This coating was less sensitive than the ZrO2.8Y2O3 coating to process variables and part geometry. Testing with fuels contaminated with compounds containing sulfur, phosphorus and alkali metals showed the zirconia coatings were destabilized. The calcium titanate coatings were not affected by these contaminants. However, when fuels were used containing 50 ppm of vanadium and 150 ppm of magnesium, heavy deposits were formed on the test specimens and combustor components that required frequent cleaning of the test rig. During the program Mars engine first-stage turbine blades were coated and installed for an engine cyclic endurance run with the zirconia, calcium titanate, and calcium silicate coatings. Heavy spalling developed with the calcium silicate system. The zirconia and calcium titanate systems survived the full test duration. It was concluded that these two TBC's showed potential for application in gas turbines.

Incidence of Treatment for Infection of Buried Versus Exposed Kirschner Wires in Phalangeal, Metacarpal, and Distal Radial Fractures.

PubMed

Ridley, Taylor J; Freking, Will; Erickson, Lauren O; Ward, Christina Marie

2017-07-01

To determine whether there is a difference in the incidence of infection between exposed and buried K-wires when used to treat phalangeal, metacarpal, and distal radius fractures. We conducted a retrospective review identifying all patients aged greater than 16 years who underwent fixation of phalangeal, metacarpal, or distal radius fractures with K-wires between 2007 and 2015. We recorded patient demographic data, fracture location, number of K-wires used, whether K-wires were buried or left exposed, and duration of K-wire placement. A total of 695 patients met inclusion criteria. Surgeons buried K-wires in 207 patients and left K-wires exposed in 488. Infections occurred more frequently in exposed K-wire cases than in buried K-wire ones. Subgroup analysis based on fracture location revealed a significantly increased risk of being treated for infection when exposed K-wires were used for metacarpal fractures. Patients with exposed K-wires for fixation of phalangeal, metacarpal, or distal radius fractures were more likely to be treated for a pin-site infection than those with K-wires buried beneath the skin. Metacarpal fractures treated with exposed K-wires were 2 times more likely to be treated for a pin-site infection (17.6% of exposed K wire cases vs 8.7% of buried K wire cases). Therapeutic IV. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Record Blizzard Buries U.S. Northeast

NASA Technical Reports Server (NTRS)

2005-01-01

After two days of blustery weather, the skies cleared over Massachusetts on January 24, 2005. Along with other northeastern U.S. states, Massachusetts was slammed with a powerful blizzard on January 22 and 23 that shut down travel and businesses and extinguished power. The storm brought record snow to many places, but Massachusetts topped the list. The cities of Salem and Plymouth were buried in 38 inches (96.5 cm) of snow, and strong winds created drifts up to seven feet (2 meters) high, according to the National Weather Service. For Boston, the storm was the fifth worst blizzard to hit the city since 1892, dumping 22.5 inches (57 cm) of snow in two days. Of that, 13.4 inches (34 cm) fell on January 23' the most snow to fall on the city in a single day since records began. These totals gave Boston nearly twice its average snowfall for January (the average is 13.5 inches, 34.3 cm), and over half its annual average snow of 41.8 inches (106 cm). This Moderate Resolution Imaging Spectroradiometer (MODIS) image, taken on January 24 by NASA's Terra satellite, shows the effects of the storm on Massachusetts and its southern neighbors, Connecticut (left) and Rhode Island (right). New York's Long Island is in the lower left corner of the image. The entire region is coated with snow, though clouds obscure the ground on the left side of the image. The snow was accompanied by powerful hurricane-force winds that helped create white-out conditions and large snowdrifts. The wind also churned ocean waters around Cape Cod, leaving them milky with sediment. NASA image courtesy the MODIS Rapid Response Team at NASA GSFC.

A study on the applicability of in-line measurements in the monitoring of the pellet coating process.

PubMed

Hudovornik, Grega; Korasa, Klemen; Vrečer, Franc

2015-07-30

Special populations including paediatric and elderly patients often need advanced approaches in treatment, such as one-a-day dosing, which is achieved with modified release formulations or alternative routes of applications such as nasogastric route. Pellets are a dosage form that is frequently used in such formulations. The aim of the present work was to study the applicability of two in-line techniques, namely, Near Infrared Spectroscopy (NIR) and Spatial Filtering Technique (SFT) in the pellet coating process. The first objective of our work was to develop a prediction model for moisture content determination with the in-line NIR and to test its robustness in terms of sensitivity to changes in composition of the pellets and performance in wide range of moisture content. Secondly, the in-line SFT measurement was correlated with different off-line particle size methods. The third objective was to evaluate the ability of both in-line techniques for the detection of undesired deviations during the process, such as pellet attrition and agglomeration. Finally, the ability to predict coating thickness with the in-line NIR probe was evaluated. Results suggested that NIR prediction model for moisture content was less robust outside the calibration range and was also sensitive to changes in composition of the film coating. Nevertheless, satisfactory prediction was achieved in the case when coating composition was partially altered and adequate calibration range was used. The SFT probe results were in good correlation with off-line particle size measurement methods and proved to be an effective tool for coating thickness determination during the coating, however, the probe failed to accurately show the actual amount of the agglomerates formed during the process. In experiment when pellet attrition was initiated, both probes successfully detected abrasion of the pellet surface in real time. Furthermore, a predictive NIR model for coating thickness was made and showed a good potential to measure coating thickness in-line, suggesting that the NIR probe can be used as a single tool to monitor water content, coating thickness, and deviations in the coating process. Copyright © 2015 Elsevier B.V. All rights reserved.

Advanced Antireflection Coatings for High-Performance Solar Energy Applications

NASA Technical Reports Server (NTRS)

Pan, Noren

2015-01-01

Phase II objectives: Develop and refine antireflection coatings incorporating lanthanum titanate as an intermediate refractive index material; Investigate wet/dry thermal oxidation of aluminum containing semiconductor compounds as a means of forming a more transparent window layer with equal or better optical properties than its unoxidized form; Develop a fabrication process that allows integration of the oxidized window layer and maintains the necessary electrical properties for contacting the solar cell; Conduct an experimental demonstration of the best candidates for improved antireflection coatings.

Coating processes for increasing the moisture resistance of polyurethane baffle material

NASA Technical Reports Server (NTRS)

Bilow, N.; Sawko, P.

1974-01-01

An investigation was conducted with the objective to improve the hydrolytic stability of reticulated polyurethane baffle material. This material is used in fuel tanks of aircraft and ground vehicles. The most commonly used foam of this type is hydrolytically unstable. Potential moisture barrier coatings which were evaluated include Parylene, epoxy-polysulfide, polyether based polyurethanes, polysulfides, polyolefin rubbers, and several other materials. Parylene coatings of at least 0.2 mil were found to provide the greatest improvement in hydrolytic stability.

Evaluation of antimicrobial edible coatings from a whey protein isolate base to improve the shelf life of cheese.

PubMed

Ramos, Ó L; Pereira, J O; Silva, S I; Fernandes, J C; Franco, M I; Lopes-da-Silva, J A; Pintado, M E; Malcata, F X

2012-11-01

The objective of this work was to evaluate the effectiveness of antimicrobial edible coatings to wrap cheeses, throughout 60 d of storage, as an alternative to commercial nonedible coatings. Coatings were prepared using whey protein isolate, glycerol, guar gum, sunflower oil, and Tween 20 as a base matrix, together with several combinations of antimicrobial compounds-natamycin and lactic acid, natamycin and chitooligosaccharides (COS), and natamycin, lactic acid, and COS. Application of coating on cheese decreased water loss (~10%, wt/wt), hardness, and color change; however, salt and fat contents were not significantly affected. Moreover, the antimicrobial edible coatings did not permit growth of pathogenic or contaminant microorganisms, while allowing regular growth of lactic acid bacteria throughout storage. Commercial nonedible coatings inhibited only yeasts and molds. The antimicrobial edible coating containing natamycin and lactic acid was the best in sensory terms. Because these antimicrobial coatings are manufactured from food-grade materials, they can be consumed as an integral part of cheese, which represents a competitive advantage over nonedible coatings. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Methods of Fabricating a Layer of Metallic Glass-Based Material Using Immersion and Pouring Techniques

NASA Technical Reports Server (NTRS)

Hofmann, Douglas (Inventor)

2015-01-01

Systems and methods in accordance with embodiments of the invention implement layers of metallic glass-based materials. In one embodiment, a method of fabricating a layer of metallic glass includes: applying a coating layer of liquid phase metallic glass to an object, the coating layer being applied in a sufficient quantity such that the surface tension of the liquid phase metallic glass causes the coating layer to have a smooth surface; where the metallic glass has a critical cooling rate less than 1000 K/s; and cooling the coating layer of liquid phase metallic glass to form a layer of solid phase metallic glass.

Integrated Glass Coating Manufacturing Line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brophy, Brenor

2015-09-30

This project aims to enable US module manufacturers to coat glass with Enki’s state of the art tunable functionalized AR coatings at the lowest possible cost and highest possible performance by encapsulating Enki’s coating process in an integrated tool that facilitates effective process improvement through metrology and data analysis for greater quality and performance while reducing footprint, operating and capital costs. The Phase 1 objective was a fully designed manufacturing line, including fully specified equipment ready for issue of purchase requisitions; a detailed economic justification based on market prices at the end of Phase 1 and projected manufacturing costs andmore » a detailed deployment plan for the equipment.« less

Buried CO2 Ice traces in South Polar Layered Deposits of Mars detected by radar sounder

NASA Astrophysics Data System (ADS)

Castaldo, L.; Mège, D.; Orosei, R.; Séjourné, A.

2014-12-01

SHARAD (SHAllow RADar) is the subsurface sounding radar provided by the Italian Space Agency (ASI) as a facility instrument to NASA's 2005 Mars Reconnaissance Orbiter (MRO). The Reduced Data Record of SHARAD data covering the area of the South Polar Layered Deposits (SPLD), has been used. The elaboration and interpretation of the data, aimed to estimate electromagnetic properties of surface layers, has been performed in terms of permittivity. The theory of electromagnetic scattering from fractal surfaces, and the estimation of geometric parameters from topographic data by Mars Orbiter Laser Altimeter (MOLA) which was one of five instruments on board the Mars Global Surveyor (MGS) spacecraft, has been used. A deep analysis of inversion has been made on all Mars and extended to the South Polar Caps in order to extract the area with a permittivity constant of CO2 ice. Several corrections have been applied to the data, moreover the calibration of the signal requires the determination of a constant that takes into account the power gain due to the radar system and the surface in order to compensate the power losses due to the orbitographic phenomena. The determination of regions with high probability of buried CO2 ice in the first layer of the Martian surface, is obtained extracting the real part of the permittivity constant of the CO2 ice (~2), estimated by other means. The permittivity of CO2ice is extracted from the Global Permittivity Map of Mars using the global standard deviation of itself as following: ɛCO2ice=ɛCO2ice+ Σ (1)where Σ=±std(ɛMapMars)/2Figure 1(a) shows the south polar areas where the values of the permittivity point to the possibility of a CO2 ice layer. Figure 1(b) is the corresponding geologic map. The comparison between the two maps indicates that the area with probable buried CO2 overlaps Hesperian and Amazonian polar units (Hp, Hesperian plains-forming deposits marked by narrow sinuous, anabranching ridges and irregular depressions, and Apu, Amazonian layered plateaus). From this analysis, the south polar cap could be covered by a thin frozen carbon dioxide coating. The perennial south polar cap is probably made of frozen carbon dioxide ca. 8 meters thick.

Semiconductor-Electrocatalyst Interfaces: Theory, Experiment, and Applications in Photoelectrochemical Water Splitting.

PubMed

Nellist, Michael R; Laskowski, Forrest A L; Lin, Fuding; Mills, Thomas J; Boettcher, Shannon W

2016-04-19

Light-absorbing semiconductor electrodes coated with electrocatalysts are key components of photoelectrochemical energy conversion and storage systems. Efforts to optimize these systems have been slowed by an inadequate understanding of the semiconductor-electrocatalyst (sem|cat) interface. The sem|cat interface is important because it separates and collects photoexcited charge carriers from the semiconductor. The photovoltage generated by the interface drives "uphill" photochemical reactions, such as water splitting to form hydrogen fuel. Here we describe efforts to understand the microscopic processes and materials parameters governing interfacial electron transfer between light-absorbing semiconductors, electrocatalysts, and solution. We highlight the properties of transition-metal oxyhydroxide electrocatalysts, such as Ni(Fe)OOH, because they are the fastest oxygen-evolution catalysts known in alkaline media and are (typically) permeable to electrolyte. We describe the physics that govern the charge-transfer kinetics for different interface types, and show how numerical simulations can explain the response of composite systems. Emphasis is placed on "limiting" behavior. Electrocatalysts that are permeable to electrolyte form "adaptive" junctions where the interface energetics change during operation as charge accumulates in the catalyst, but is screened locally by electrolyte ions. Electrocatalysts that are dense, and thus impermeable to electrolyte, form buried junctions where the interface physics are unchanged during operation. Experiments to directly measure the interface behavior and test the theory/simulations are challenging because conventional photoelectrochemical techniques do not measure the electrocatalyst potential during operation. We developed dual-working-electrode (DWE) photoelectrochemistry to address this limitation. A second electrode is attached to the catalyst layer to sense or control current/voltage independent from that of the semiconductor back ohmic contact. Consistent with simulations, electrolyte-permeable, redox-active catalysts such as Ni(Fe)OOH form "adaptive" junctions where the effective barrier height for electron exchange depends on the potential of the catalyst. This is in contrast to sem|cat interfaces with dense electrolyte-impermeable catalysts, such as nanocrystalline IrOx, that behave like solid-state buried (Schottky-like) junctions. These results elucidate a design principle for catalyzed photoelectrodes. The buried heterojunctions formed by dense catalysts are often limited by Fermi-level pinning and low photovoltages. Catalysts deposited by "soft" methods, such as electrodeposition, form adaptive junctions that tend to provide larger photovoltages and efficiencies. We also preview efforts to improve theory/simulations to account for the presence of surface states and discuss the prospect of carrier-selective catalyst contacts.

Effects of Psilocybe argentipes on marble-burying behavior in mice.

PubMed

Matsushima, Yoshihiro; Shirota, Osamu; Kikura-Hanajiri, Ruri; Goda, Yukihiro; Eguchi, Fumio

2009-08-01

Psilocybe argentipes is a hallucinogenic mushroom. The present study examined the effects of P. argentipes on marble-burying behavior, which is considered an animal model of obsessive-compulsive disorder. P. argentipes significantly inhibited marble-burying behavior without affecting locomotor activity as compared with the same dose of authentic psilocybin. These findings suggest that P. argentipes would be efficient in clinical obsessive-compulsive disorder therapy.

Exposed versus buried intramedullary implants for pediatric forearm fractures: a comparison of complications.

PubMed

Kelly, Brian A; Miller, Patricia; Shore, Benjamin J; Waters, Peter M; Bae, Donald S

2014-12-01

The purpose of this study was to compare the rate of complications between buried and exposed intramedullary implants after fixation of pediatric forearm fractures. A retrospective comparative cohort study of 339 children treated with intramedullary fixation for displaced forearm fractures between 2004 and 2009 was performed. Implants were left exposed in 128 patients (37.8%) and buried beneath the skin in 208 patients (61.4%); 3 patients had buried and exposed hardware (0.9%). Data on demographics, injury, surgical technique, and complications were analyzed. The buried implant group was older (mean 10.3 vs. 8.5 y; P < 0.001), heavier (mean 38.6 vs. 31.9 kg; P < 0.001), and had fewer open injuries (23% vs. 41%; P < 0.001) than the exposed implant group. The buried group had their implants removed later than the exposed group (median 3.5 vs. 1.2 mo; P < 0.001). There was no difference between time to removal for patients with refracture and those without (median 1.3 vs. 2.0 mo; P = 0.78). A total of 36.2% of exposed implants were successfully removed in the office. Complications were seen in 56 patients (16.5%). There were 16 patients (4.7%) with refracture and 12 patients (3.5%) with infection. The buried and exposed implant groups did not differ significantly with respect to refracture (3.1% vs. 7.0%; P = 0.20), infection (3.5% vs. 2.3%; P = 0.66), or overall complications (14.5% vs. 17.2%; P = 0.87). There was also no difference between groups with respect to loss of reduction, nondelayed or delayed union, loss of motion, hypertrophic granuloma, or tendon rupture. Buried implants were also associated with penetration through the skin (3.9%). Injury to the dominant arm and need for open reduction were significant predictors of complication (OR = 1.01; 95% CI, 1.001-1.012; P = 0.02 and OR = 0.51; 95% CI, 0.264-0.974; P = 0.04, respectively). There were no significant differences seen in number of infections, refractures, or overall complications based on whether implants were left exposed or buried beneath the skin after surgery. Level III, therapeutic.

Bioactive coating with low-fouling polymers for the development of biocompatible vascular implants

NASA Astrophysics Data System (ADS)

Thalla, Pradeep Kumar

The replacement of occluded blood vessels and endovascular aneurysm repair (EVAR) are performed with the use of synthetic vascular grafts and stent grafts, respectively. Both implants lead to frequent clinical complications that are different but due to a similar problem, namely the inadequate surface properties of the polymeric biomaterials used (generally polyethylene terephthalate (PET) or expanded polytetrafluoroethylene (ePTFE)). Therefore the general objective of this thesis was to create a versatile bioactive coating on vascular biomaterials that reduce material-induced thrombosis and promote desired cell interactions favorable to tissue healing around implants. The use of low-fouling backgrounds was decided in order to reduce platelet adhesion as well as the non-specific protein adsorption and thus increase the bioactivity of immobilized biomolecules. As part of the preliminary objective, a multi-arm polyethylene glycol (PEG) was chosen to create a versatile low-fouling surface, since the current coating methods are far from being versatile and rely on the availability of compatible functional groups on both PEG and the host surface. This PEG coating method was developed by taking advantage of novel primary amine-rich plasma polymerized coatings (LP). As demonstrated by quartz crystal microbalance with dissipation (QCM-D), fluorescence measurements and platelet adhesion assays, our PEG coatings exhibited low protein adsorption and almost no platelet adhesion after 15 min perfusion in whole blood. Although protein adsorption was not completely abrogated and short-term platelet adhesion assay was clearly insufficient to draw conclusions for long-term prevention of thrombosis in vivo, the low-fouling properties of this PEG coating were sufficient to be exploited for further coupling of bioactive molecules to create bioactive coatings. Therefore, as a part of the second objective, an innovative and versatile bioactive coating was developed on PEG and carboxymethylated dextran (CMD), using the combination of an adhesive peptide (KQAGDV/RGD) and epidermal growth factor (EGF). CMD was chosen as an alternative to PEG due to its better low-fouling properties and the presence of abundant carboxyl terminal groups. Although the QCM-D technique enabled us to optimize the combined immobilization of KQAGDV/RGD and EGF, cell adhesion assay results did not show improvement of vascular smooth muscle cell (VSMC) adhesion on peptide-modified PEG or CMD surfaces. Among the reasons explaining low cell adhesion on peptides grafted low-fouling surfaces is the difficulty of preventing protein adsorption/platelet adhesion without significantly reducing cell adhesion. Preliminary data in our laboratory indicated that CS could be an ideal substrate to find this compromise. For that reason, the final objective of this PhD consisted in evaluating the potential of chondroitin sulfate (CS) coating by comparing its properties with well-known low-fouling polymers such as PEG and CMD. It was shown that CS presents selective low-fouling properties, low-platelet adhesion and pro-endothelial cell (EC) adhesive properties As demonstrated by QCM-D and fluorescence measurements, CS was as effective as PEG in reducing fibrinogen adsorption, but it reduced adsorption of bovine serum albumin (BSA) and fetal bovine serum (FBS) to a lower extent than PEG and CMD surfaces. Whole blood perfusion assays indicated that all three surfaces drastically decreased platelet adhesion and activation to levels significantly lower than PET surfaces. However, while EC adhesion and growth were found to be very limited on PEG and CMD, cell attachment on CS was strong, with focal adhesion points and resistance to shear stress. CS coatings therefore form a low-thrombogenic background promoting the formation of a confluent endothelium layer, which may then act as an active anti-thrombogenic surface. CS coating can also be used to further graft biomolecules. Combination of LP, CS coating followed by GF immobilization shows great promise as a bioactive coating to optimize the biocompatibility and clinical outcome of vascular implants, in particular vascular grafts.

Active coatings technologies for tailorable military coating systems

NASA Astrophysics Data System (ADS)

Zunino, J. L., III

2007-04-01

The main objective of the U.S. Army's Active Coatings Technologies Program is to develop technologies that can be used in combination to tailor coatings for utilization on Army Materiel. The Active Coatings Technologies Program, ACT, is divided into several thrusts, including the Smart Coatings Materiel Program, Munitions Coatings Technologies, Active Sensor packages, Systems Health Monitoring, Novel Technology Development, as well as other advanced technologies. The goal of the ACT Program is to conduct research leading to the development of multiple coatings systems for use on various military platforms, incorporating unique properties such as self repair, selective removal, corrosion resistance, sensing, ability to modify coatings' physical properties, colorizing, and alerting logistics staff when tanks or weaponry require more extensive repair. A partnership between the U.S. Army Corrosion Office at Picatinny Arsenal, NJ along with researchers at the New Jersey Institute of Technology, NJ, Clemson University, SC, University of New Hampshire, NH, and University of Massachusetts (Lowell), MA, are developing the next generation of Smart Coatings Materiel via novel technologies such as nanotechnology, Micro-electromechanical Systems (MEMS), meta-materials, flexible electronics, electrochromics, electroluminescence, etc. This paper will provide the reader with an overview of the Active Coatings Technologies Program, including an update of the on-going Smart Coatings Materiel Program, its progress thus far, description of the prototype Smart Coatings Systems and research tasks as well as future nanotechnology concepts, and applications for the Department of Defense.

Irradiation performance of HTGR fuel rods in HFIR experiments HRB-7 and -8

DOE Office of Scientific and Technical Information (OSTI.GOV)

Valentine, K.H.; Homan, F.J.; Long, E.L. Jr.

1977-05-01

The HRB-7 and -8 experiments were designed as a comprehensive test of mixed thorium-uranium oxide fissile particles with Th:U ratios from 0 to 8 for HTGR recycle application. In addition, fissile particles derived from Weak-Acid Resin (WAR) were tested as a potential backup type of fissile particle for HTGR recycle. These experiments were conducted at two temperatures (1250 and 1500/sup 0/C) to determine the influence of operating temperature on the performance parameters studied. The minor objectives were comparison of advanced coating designs where ZrC replaced SiC in the Triso design, testing of fuel coated in laboratory-scale equipment with fuel coatedmore » in production-scale coaters, comparison of the performance of /sup 233/U-bearing particles with that of /sup 235/U-bearing particles, comparison of the performance of Biso coatings with Triso coatings for particles containing the same type of kernel, and testing of multijunction tungsten-rhenium thermocouples. All objectives were accomplished. As a result of these experiments the mixed thorium-uranium oxide fissile kernel was replaced by a WAR-derived particle in the reference recycle design. A tentative decision to make this change had been reached before the HRB-7 and -8 capsules were examined, and the results of the examination confirmed the accuracy of the previous decision. Even maximum dilution (Th/U approximately equal to 8) of the mixed thorium-uranium oxide kernel was insufficient to prevent amoeba of the kernels at rates that are unacceptable in a large HTGR. Other results showed the performance of /sup 233/U-bearing particles to be identical to that of /sup 235/U-bearing particles, the performance of fuel coated in production-scale equipment to be at least as good as that of fuel coated in laboratory-scale coaters, the performance of ZrC coatings to be very promising, and Biso coatings to be inferior to Triso coatings relative to fission product retention.« less

Inactivation of Salmonella in tomato stem scars by organic acid wash and chitosan-allyl isothiocyanate coating

USDA-ARS?s Scientific Manuscript database

The objective of this study was to evaluate inactivation of inoculated Salmonella enterica on tomato stem scars exploiting integrated treatment of organic acid wash (AW) followed by chitosan-allyl isothiocyanate (CT-AIT) coating. The treatment effect on microbial loads and fruit quality during 21 d...

Annual Report - Compatibility of ZDDP and ionic liquid anti-wear additives with hard coatings for engine lubrications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qu, Jun; Zhou, Yan; Leonard, Donovan N

The objectives for this considerations described here are to; investigate the compatibility of engine lubricant antiwear (AW) additives, specifically conventional zinc dialkyldithiophosphate (ZDDP) and newly developed ionic liquids (ILs), with selected commercial hard coatings, and provide fundamental understanding to guide future development of engine lubricants.

Computer simulation of explosion crater in dams with different buried depths of explosive

NASA Astrophysics Data System (ADS)

Zhang, Zhichao; Ye, Longzhen

2018-04-01

Based on multi-material ALE method, this paper conducted a computer simulation on the explosion crater in dams with different buried depths of explosive using LS-DYNA program. The results turn out that the crater size increases with the increase of buried depth of explosive at first, but closed explosion cavity rather than a visible crater is formed when the buried depth of explosive increases to some extent. The soil in the explosion cavity is taken away by the explosion products and the soil under the explosion cavity is compressed with its density increased. The research can provide some reference for the anti-explosion design of dams in the future.

X-ray diffraction analysis of hydroxyapatite-coated in different plasma gas atmosphere on Ti and Ti-6Al-4V

PubMed Central

Kotian, Ravindra; Rao, P. Prasad; Madhyastha, Prashanthi

2017-01-01

Objective: The aim is to study the effect of plasma working gas on composition, crystallinity, and microstructure of hydroxyapatite (HA) coated on Ti and Ti-6Al-4V metal substrates. Materials and Methods: Ti and Ti-6Al-4V metal substrates were coated with HA by plasma spray using four plasma gas atmospheres of argon, argon/hydrogen, nitrogen, and nitrogen/hydrogen. The degree of crystallinity, the phases present, and microstructure of HA coating were characterized using X-ray diffraction and scanning electron microscopy. Results: Variation in crystallinity and the microstructure of HA coating on plasma gas atmosphere was observed. Micro-cracks due to thermal stresses and shift in the 2θ angle of HA compared to feedstock was seen. Conclusion: Plasma gas atmosphere has a significant influence on composition, crystallinity, and micro-cracks of HA-coated dental implants. PMID:29279668

The effect of immersion time to low carbon steel hardness and microstructure with hot dip galvanizing coating method

NASA Astrophysics Data System (ADS)

Hakim, A. A.; Rajagukguk, T. O.; Sumardi, S.

2018-01-01

Along with developing necessities of metal materials, these rise demands of quality improvements and material protections especially the mechanical properties of the material. This research used hot dip galvanizing coating method. The objectives of this research were to find out Rockwell hardness (HRb), layer thickness, micro structure and observation with Scanning Electron Microscope (SEM) from result of coating by using Hot Dip Galvanizing coating method with immersion time of 3, 6, 9, and 12 minutes at 460°C. The result shows that Highest Rockwell hardness test (HRb) was at 3 minutes immersion time with 76.012 HRb. Highest thickness result was 217.3 μm at 12 minutes immersion. Microstructure test result showed that coating was formed at eta, zeta, delta and gamma phases, while Scanning Electron Microscope (SEM) showed Fe, Zn, Mn, Si and S elements at the specimens after coating.

Compressor coating effects on gas turbine engine performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacLeod, J.D.; Laflamme, J.C.

1991-10-01

In an attempt to increase the time between maintenance actions and to improve performance retention of turboprop engines installed in transport and maritime patrol aircraft, the Canadian Department of National Defence is evaluating an erosion and corrosion-resistance blade coating, for use on compressors. As coatings could appreciably alter engine performance by virtue of their application thickness and surface quality, the National Research Council of Canada was asked to quantify any performance changes that could occur. A project was initiated, utilizing a new Allison T56 turboprop engine, to assess not only the performance changes resulting from the coating, but also thosemore » from dismantling and reassembling the compressor, since the compressor must be completely disassembled to apply the coating. This paper describes the project objectives, the experimental installation, and the measured effects of the coating application on compressor performance.« less

Surface-agnostic highly stretchable and bendable conductive MXene multilayers

PubMed Central

An, Hyosung; Habib, Touseef; Shah, Smit; Gao, Huili; Radovic, Miladin; Green, Micah J.; Lutkenhaus, Jodie L.

2018-01-01

Stretchable, bendable, and foldable conductive coatings are crucial for wearable electronics and biometric sensors. These coatings should maintain functionality while simultaneously interfacing with different types of surfaces undergoing mechanical deformation. MXene sheets as conductive two-dimensional nanomaterials are promising for this purpose, but it is still extremely difficult to form surface-agnostic MXene coatings that can withstand extreme mechanical deformation. We report on conductive and conformal MXene multilayer coatings that can undergo large-scale mechanical deformation while maintaining a conductivity as high as 2000 S/m. MXene multilayers are successfully deposited onto flexible polymer sheets, stretchable poly(dimethylsiloxane), nylon fiber, glass, and silicon. The coating shows a recoverable resistance response to bending (up to 2.5-mm bending radius) and stretching (up to 40% tensile strain), which was leveraged for detecting human motion and topographical scanning. We anticipate that this discovery will allow for the implementation of MXene-based coatings onto mechanically deformable objects. PMID:29536044

Effect of surface coating with magnesium stearate via mechanical dry powder coating approach on the aerosol performance of micronized drug powders from dry powder inhalers.

PubMed

Zhou, Qi Tony; Qu, Li; Gengenbach, Thomas; Larson, Ian; Stewart, Peter J; Morton, David A V

2013-03-01

The objective of this study was to investigate the effect of particle surface coating with magnesium stearate on the aerosolization of dry powder inhaler formulations. Micronized salbutamol sulphate as a model drug was dry coated with magnesium stearate using a mechanofusion technique. The coating quality was characterized by X-ray photoelectron spectroscopy. Powder bulk and flow properties were assessed by bulk densities and shear cell measurements. The aerosol performance was studied by laser diffraction and supported by a twin-stage impinger. High degrees of coating coverage were achieved after mechanofusion, as measured by X-ray photoelectron spectroscopy. Concomitant significant increases occurred in powder bulk densities and in aerosol performance after coating. The apparent optimum performance corresponded with using 2% w/w magnesium stearate. In contrast, traditional blending resulted in no significant changes in either bulk or aerosolization behaviour compared to the untreated sample. It is believed that conventional low-shear blending provides insufficient energy levels to expose host micronized particle surfaces from agglomerates and to distribute guest coating material effectively for coating. A simple ultra-high-shear mechanical dry powder coating step was shown as highly effective in producing ultra-thin coatings on micronized powders and to substantially improve the powder aerosolization efficiency.

Optimal imaging and analysis of human vaginal coating by drug delivery gels

PubMed Central

Henderson, Marcus H; Couchman, Grace M; Walmer, David K; Peters, Jennifer J; Owen, Derek H; Brown, Matthew A; Lavine, Michael L; Katz, David F

2007-01-01

Objective We used a new optical imaging technique to compare human intravaginal coating distributions of Conceptrol® and Advantage™. These gels are surrogates for future microbicidal gels, differing in molecular structures and biophysical properties. Methods For each protocol, a 3-mL gel bolus was inserted to the posterior fornix while the woman was in the supine position. She then either: (1) remained supine (10 min); or (2) sat up (1 min), stood up (1 min), sat down (1 min), and returned to supine for a net elapsed time of 10 min. The imaging device is sized/shaped like a phallus, and measurements while the device was inserted provide data that simulate peri-intromission coating. Results Coating by Advantage™ was more extensive and uniform than coating by Conceptrol®, with smaller bare spots of uncoated epithelium. Change in posture tended to increase extent and uniformity of coating, details differing between gels. Conclusions Results are consistent with predictions of mechanistic coating theory, using gel rheological data as inputs. PMID:17241845

Superior broadband antireflection from buried Mie resonator arrays for high-efficiency photovoltaics

PubMed Central

Zhong, Sihua; Zeng, Yang; Huang, Zengguang; Shen, Wenzhong

2015-01-01

Establishing reliable and efficient antireflection structures is of crucial importance for realizing high-performance optoelectronic devices such as solar cells. In this study, we provide a design guideline for buried Mie resonator arrays, which is composed of silicon nanostructures atop a silicon substrate and buried by a dielectric film, to attain a superior antireflection effect over a broadband spectral range by gaining entirely new discoveries of their antireflection behaviors. We find that the buried Mie resonator arrays mainly play a role as a transparent antireflection structure and their antireflection effect is insensitive to the nanostructure height when higher than 150 nm, which are of prominent significance for photovoltaic applications in the reduction of photoexcited carrier recombination. We further optimally combine the buried Mie resonator arrays with micron-scale textures to maximize the utilization of photons, and thus have successfully achieved an independently certified efficiency of 18.47% for the nanostructured silicon solar cells on a large-size wafer (156 mm × 156 mm). PMID:25746848

Detection and characterization of buried lunar craters with GRAIL data

NASA Astrophysics Data System (ADS)

Sood, Rohan; Chappaz, Loic; Melosh, Henry J.; Howell, Kathleen C.; Milbury, Colleen; Blair, David M.; Zuber, Maria T.

2017-06-01

We used gravity mapping observations from NASA's Gravity Recovery and Interior Laboratory (GRAIL) to detect, characterize and validate the presence of large impact craters buried beneath the lunar maria. In this paper we focus on two prominent anomalies detected in the GRAIL data using the gravity gradiometry technique. Our detection strategy is applied to both free-air and Bouguer gravity field observations to identify gravitational signatures that are similar to those observed over buried craters. The presence of buried craters is further supported by individual analysis of regional free-air gravity anomalies, Bouguer gravity anomaly maps, and forward modeling. Our best candidate, for which we propose the informal name of Earhart Crater, is approximately 200 km in diameter and forms part of the northwestern rim of Lacus Somniorum, The other candidate, for which we propose the informal name of Ashoka Anomaly, is approximately 160 km in diameter and lies completely buried beneath Mare Tranquillitatis. Other large, still unrecognized, craters undoubtedly underlie other portions of the Moon's vast mare lavas.

Kirschner wire pin tract infection rates between percutaneous and buried wires in treating metacarpal and phalangeal fractures.

PubMed

Rafique, Atif; Ghani, Shahab; Sadiq, Moiz; Siddiqui, Intisar Ahmed

2006-08-01

To compare pin tract infection rate between percutaneous and buried placement of Kirschner (K-) wiring for hand fractures. Quasi--experimental study. Plastic, Reconstructive, Hand and Burn Surgery Unit, Liaquat National Hospital, Karachi, from September 2005--February 2006. Patients with fractures of metacarpals and phalanges of hand were selected by non-probability purposive method. Assessment of pin tract infection by clinical examination and pin tract scoring was done by modification of Oppenheim classification. Statistical analysis was done using Chi-square test. Ten out of 55 percutaneous and 2 out of 45 buried wires were infected. The difference in infection rates of two groups was statistically significant at p<0.05. Three percutaneous, but not buried Kirschner wires, had to be removed before 4 weeks because of failure to respond to local wound care and oral antibiotics. Percutaneous K- wires had significantly greater infection rate than wires which were buried deep to the skin.

Exhuming Crater in Northeast Arabia

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-563, 3 December 2003

The upper crust of Mars is layered, and interbedded with these layers are old, filled and buried meteor impact craters. In a few places on Mars, such as Arabia Terra, erosion has re-exposed some of the filled and buried craters. This October 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example. The larger circular feature was once a meteor crater. It was filled with sediment, then buried beneath younger rocks. The smaller circular feature is a younger impact crater that formed in the surface above the rocks that buried the large crater. Later, erosion removed all of the material that covered the larger, buried crater, except in the location of the small crater. This pair of martian landforms is located near 17.6oN, 312.8oW. The image covers an area 3 km (1.9 mi) wide and is illuminated from the lower left.

Porcelain-coated antenna for radio-frequency driven plasma source

DOEpatents

Leung, Ka-Ngo; Wells, Russell P.; Craven, Glen E.

1996-01-01

A new porcelain-enamel coated antenna creates a clean plasma for volume or surface-conversion ion sources. The porcelain-enamel coating is hard, electrically insulating, long lasting, non fragile, and resistant to puncture by high energy ions in the plasma. Plasma and ion production using the porcelain enamel coated antenna is uncontaminated with filament or extraneous metal ion because the porcelain does not evaporate and is not sputtered into the plasma during operation. Ion beams produced using the new porcelain-enamel coated antenna are useful in ion implantation, high energy accelerators, negative, positive, or neutral beam applications, fusion, and treatment of chemical or radioactive waste for disposal. For ion implantation, the appropriate species ion beam generated with the inventive antenna will penetrate large or small, irregularly shaped conducting objects with a narrow implantation profile.

Effect of concentration of Curcuma longa L. on chitosan-starch based edible coating

NASA Astrophysics Data System (ADS)

Yusof, N. M.; Jai, J.; Hamzah, F.; Yahya, A.; Pinijsuwan, S.

2017-08-01

The ability of chitosan-starch based coating to extend shelf life of strawberry were studied. The main objectives of this paper is to study the effects of different concentrations (20, 15, 10 and 5 µL) of Curcuma longa L. (CUR) essential oil into chitosan-based edible coating on surface tension in order to increase the effectiveness of the coating. CUR or turmeric is one of the commercially planted herbs in Malaysia for its phytochemical benefits. Application of edible coating using dipping technique has been analysed and evaluated for their effectiveness in extending shelf life of fruits. Surface tension was analysed to investigate the adhesion properties. The best CUR concentration was 15 µL with the optimum surface tension was found to be 31.92 dynes/cm.

Authigenic chlorite as a controlling factor in the exploration of Turonian/Coniacian turbidites in the Santos Basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porsche, E.; Lopes de Freitas, E.

1996-08-01

Upper Turonian/Coniacian and Campanian turbidites are major targets for petroleum exploration in the Santos Basin, southeastern Brazil. They occur between 140 and 1000 m of present water depth, are buried at about 4500 m, and reach thickness of up to 60 m. The main reservoir facies is composed of unstratified, fine to very fine grained, poorly sorted sandstones, which framework is compositionally immature, including a high proportion of feldspars and volcanic rock fragments. Early coating of grains by authigenic chlorite inhibited pressure solution and quartz cementation in the reservoir. This diagenetic characteristic allowed important preservation of primary porosity (>20%) inmore » the reservoir; nevertheless its permeability never exceeds 30 ml. The study of sedimentary facies and related depositional processes has been conducted to predict the distribution of petroleum-bearing turbidites throughout the Santos Basin; this comprises a major challenge for the petroleum exploration in this important Brazilian exploration frontier.« less

Electromagnetic pulse excitation of finite- and infinitely-long lossy conductors over a lossy ground plane

DOE PAGES

Campione, Salvatore; Warne, Larry K.; Basilio, Lorena I.; ...

2017-01-13

This study details a model for the response of a finite- or an infinite-length wire interacting with a conducting ground to an electromagnetic pulse excitation. We develop a frequency–domain method based on transmission line theory that we name ATLOG – Analytic Transmission Line Over Ground. This method is developed as an alternative to full-wave methods, as it delivers a fast and reliable solution. It allows for the treatment of finite or infinite lossy, coated wires, and lossy grounds. The cases of wire above ground, as well as resting on the ground and buried beneath the ground are treated. The reportedmore » method is general and the time response of the induced current is obtained using an inverse Fourier transform of the current in the frequency domain. The focus is on the characteristics and propagation of the transmission line mode. Comparisons with full-wave simulations strengthen the validity of the proposed method.« less

Simulations of Si-PIN photodiode based detectors for underground explosives enhanced by ammonium nitrate

NASA Astrophysics Data System (ADS)

Yücel, Mete; Bayrak, Ahmet; Yücel, Esra Barlas; Ozben, Cenap S.

2018-02-01

Massive Ammonium Nitrate (NH4-NO3) based explosives buried underground are commonly used in terror attacks. These explosives can be detected using neutron scattering method with some limitations. Simulations are very useful tools for designing a possible detection system for these kind of explosives. Geant4 simulations were used for generating neutrons at 14 MeV energy and tracking them through the scattering off the explosive embedded in soil. Si-PIN photodiodes were used as detector elements in the design for their low costs and simplicity for signal readout electronics. Various neutron-charge particle converters were applied on to the surface of the photodiodes to increase the detection efficiency. Si-PIN photodiodes coated with 6LiF provided the best result for a certain energy interval. Energy depositions in silicon detector from all secondary particles generated including photons were taken into account to generate a realistic background. Humidity of soil, one of the most important parameter for limiting the detection, was also studied.

Electromagnetic pulse excitation of finite- and infinitely-long lossy conductors over a lossy ground plane

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campione, Salvatore; Warne, Larry K.; Basilio, Lorena I.

This study details a model for the response of a finite- or an infinite-length wire interacting with a conducting ground to an electromagnetic pulse excitation. We develop a frequency–domain method based on transmission line theory that we name ATLOG – Analytic Transmission Line Over Ground. This method is developed as an alternative to full-wave methods, as it delivers a fast and reliable solution. It allows for the treatment of finite or infinite lossy, coated wires, and lossy grounds. The cases of wire above ground, as well as resting on the ground and buried beneath the ground are treated. The reportedmore » method is general and the time response of the induced current is obtained using an inverse Fourier transform of the current in the frequency domain. The focus is on the characteristics and propagation of the transmission line mode. Comparisons with full-wave simulations strengthen the validity of the proposed method.« less

Circles and Streaks

NASA Technical Reports Server (NTRS)

2003-01-01

MGS MOC Release No. MOC2-544, 14 November 2003

This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, acquired less than a week ago on 8 November 2003, shows a typical southern middle-to-high latitude scene at this time of year. It is summer in the southern hemisphere, and regions such as Promethei Terra, where this image was acquired, are being streaked by dust devils that remove or disrupt the coating of dust that was deposited over the region in the previous autumn or winter. While no active dust devils were captured in this scene, their tell-tale tracks are scratched all across the image. The circular features are the sites of buried meteor impact craters; their rims form dark rings; the material that fills the craters has become cracked. This picture is located near 68.1oS, 247.9oW. The area shown is approximately 3 km (1.9 mi) across and is illuminated by sunlight from the upper left.

Biodegradability of regenerated cellulose films in soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, L.; Liu, H.; Zheng, L.

1996-12-01

Regenerated cellulose films and a water-resistant film coated with thin Tung oil were prepared by using a cellulose cuoxam solution from pulps of cotton linter, cotton stalk, and wheat straw. They were buried in the soil to test biodegradability. The results showed that viscosity average molecular weight M{sub {eta}}, tensile strength {sigma}{sub b}, and the weight of the degraded films decreased sharply with the progress of degradation time, and the kinetics of decay were discussed. The degradation half-lives t{sub 1/2} of the films in soil at 10--20 C were given to be 30--42 days, and after 2 months the filmsmore » were decomposed into CO{sub 2} and water. The {alpha}-cellulose in soil was more readily biodegraded than hemicellulose, and regenerated cellulose film was more readily biodegraded than kraft paper. Nuclear magnetic resonance and scanning electron micrographs indicated that the biodegradation process of the films was performed through random breakdown of bonds of cellulose macromolecules resulting from the microorganism cleavage.« less

Compact Buried Ducts in a Hot-Humid Climate House

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mallay, D.

2016-01-01

A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval.

Dental disease and dietary isotopes of individuals from St Gertrude Church cemetery, Riga, Latvia.

PubMed

Petersone-Gordina, Elina; Roberts, Charlotte; Millard, Andrew R; Montgomery, Janet; Gerhards, Guntis

2018-01-01

This research explores oral health indicators and stable carbon and nitrogen isotope data to explore diet, and differences in diet, between people buried in the four different contexts of the St Gertrude Church cemetery (15th- 17th centuries AD): the general cemetery, two mass graves, and a collective mass burial pit within the general cemetery. The main aim is to assess whether people buried in the mass graves were rural immigrants, or if they were more likely to be the victims of plague (or another epidemic) who lived in Riga and its suburbs. The data produced (from dental disease assessments and isotope analyses) were compared within, as well as between, the contexts. Most differences emerged when comparing the prevalence rates of dental diseases and other oral health indicators in males and females between the contexts, while isotope analysis revealed more individual, rather than context-specific, differences. The data suggested that the populations buried in the mass graves were different from those buried in the general cemetery, and support the theory that rural immigrants were buried in both mass graves. Significant differences were observed in some aspects of the data between the mass graves, however, possibly indicating that the people buried in them do not represent the same community.

Dental disease and dietary isotopes of individuals from St Gertrude Church cemetery, Riga, Latvia

PubMed Central

Roberts, Charlotte; Millard, Andrew R.; Montgomery, Janet; Gerhards, Guntis

2018-01-01

This research explores oral health indicators and stable carbon and nitrogen isotope data to explore diet, and differences in diet, between people buried in the four different contexts of the St Gertrude Church cemetery (15th– 17th centuries AD): the general cemetery, two mass graves, and a collective mass burial pit within the general cemetery. The main aim is to assess whether people buried in the mass graves were rural immigrants, or if they were more likely to be the victims of plague (or another epidemic) who lived in Riga and its suburbs. The data produced (from dental disease assessments and isotope analyses) were compared within, as well as between, the contexts. Most differences emerged when comparing the prevalence rates of dental diseases and other oral health indicators in males and females between the contexts, while isotope analysis revealed more individual, rather than context-specific, differences. The data suggested that the populations buried in the mass graves were different from those buried in the general cemetery, and support the theory that rural immigrants were buried in both mass graves. Significant differences were observed in some aspects of the data between the mass graves, however, possibly indicating that the people buried in them do not represent the same community. PMID:29364968

Friction and fretting wear characteristics of different diamond-like carbon coatings against alumina in water-lubricated fretting conditions.

PubMed

Watabe, Tsukasa; Amanov, Auezhan; Tsuboi, Ryo; Sasaki, Shinya

2013-12-01

Diamond-like carbon (DLC) coatings typically show low friction and high wear resistance. In this study, the friction and fretting wear characteristics of PVD, CVD and CVD-Si DLC coatings were investigated against an alumina (Al2O3) ball under water-lubricated fretting conditions. The objective of this study is to investigate and compare the friction and fretting wear characteristics of those DLC coatings at various fretting frequencies. The test results showed that the PVD DLC coating led to a lower friction coefficient and a higher resistance to fretting wear compared to those of the CVD and CVD-Si DLC coatings. However, the CVD DLC coating showed that the fretting wear resistance decreases with increasing frequency, while no significant difference in fretting wear resistances of the PVD and CVD-Si DLC coatings was observed. Quantitative surface analyses of the specimens were performed using an energy dispersive spectroscopy (EDS), a laser scanning microscope (LSM), a scanning electron microscope (SEM), an atomic force microscope (AFM) and the Raman spectroscopy.

Postharvest shelf-life extension of pink guavas (Psidium guajava L.) using HPMC-based edible surface coatings.

PubMed

Vishwasrao, Chandrahas; Ananthanarayan, Laxmi

2016-04-01

Psidium guajava L. var. 'Lalit' is a perishable fruit with delicate skin which is prone to damage. The objective of this study was to determine the effect of edible coating made up of hydroxypropyl methyl cellulose and palm oil on ripening of guava. Coating solution was applied over fruits and coated fruits were stored at 24 ± 1 °C and 65 ± 5%RH. Changes in fruit colour, texture softening, respiration rate, weight loss, ascorbic acid content, soluble solids, titrable acidity, chlorophyll content, total reducing sugars, total phenolic content were studied during post-harvest ripening. Fruits coated with 1 % of hydroxypropyl methyl cellulose and 0.3 % of palm oil showed significant delay in weight loss, fruit firmness as well as colour change (p < 0.05). Coating delayed the enzyme activities of peroxidase and polyphenol oxidase of the fruit. Results suggest that overall quality of coated fruit was maintained by edible coating formulation extending the shelf life of fruit up to 12 days with appreciable retention of all quality parameters tested.

Quantitative 3D model of light transmittance through translucent rocks applied to the hypolithic microbial community.

PubMed

Jolitz, Rebecca D; McKay, Christopher P

2013-07-01

In extreme desert environments, photosynthetic microorganisms often live on the buried undersides of translucent rocks. Computing the light level reaching these locations requires 3D modeling of a finite rock. We report on Monte Carlo calculations of skylight and sunlight transmission through a partially buried flat cylindrical rock using one billion photons per simulation. Transmitted light level drops inversely with increasing rock opacity, as expected for purely scattering media. For a half-buried rock with an extinction coefficient of 0.1 cm(-1) (opacity of 0.2), transmission at the bottom is 64 % for sunlight at a solar zenith angle of 60° and 82 % for skylight. Transmitted light level increases slowly with increasing scattering asymmetry factor of the rock independent of illumination or depth buried. Transmitted sunlight at zenith through a thick half-buried rock (opacity of 0.6) is six times brighter at the bottom than the subsurface sides. Skylight transmits equally to the subsurface sides and bottom. When the sun is not straight overhead, the sunward side of the rock is brighter than the underside of the rock. Compared to the sunlight transmitted to the bottom, transmitted sunlight inclined at 60° is 24 times brighter at the subsurface side towards the sun and 14 times brighter at the subsurface side 70° away from the sun. Transmitted sunlight emitted from zenith and skylight is uniformly bright at the bottom regardless of how deeply the rock is buried. Sunlight not at zenith transmits preferentially to the sunward bottom edge depending on the depth the rock is buried.

Distinct microbial communities associated with buried soils in the Siberian tundra

PubMed Central

Gittel, Antje; Bárta, Jiří; Kohoutová, Iva; Mikutta, Robert; Owens, Sarah; Gilbert, Jack; Schnecker, Jörg; Wild, Birgit; Hannisdal, Bjarte; Maerz, Joeran; Lashchinskiy, Nikolay; Čapek, Petr; Šantrůčková, Hana; Gentsch, Norman; Shibistova, Olga; Guggenberger, Georg; Richter, Andreas; Torsvik, Vigdis L; Schleper, Christa; Urich, Tim

2014-01-01

Cryoturbation, the burial of topsoil material into deeper soil horizons by repeated freeze–thaw events, is an important storage mechanism for soil organic matter (SOM) in permafrost-affected soils. Besides abiotic conditions, microbial community structure and the accessibility of SOM to the decomposer community are hypothesized to control SOM decomposition and thus have a crucial role in SOM accumulation in buried soils. We surveyed the microbial community structure in cryoturbated soils from nine soil profiles in the northeastern Siberian tundra using high-throughput sequencing and quantification of bacterial, archaeal and fungal marker genes. We found that bacterial abundances in buried topsoils were as high as in unburied topsoils. In contrast, fungal abundances decreased with depth and were significantly lower in buried than in unburied topsoils resulting in remarkably low fungal to bacterial ratios in buried topsoils. Fungal community profiling revealed an associated decrease in presumably ectomycorrhizal (ECM) fungi. The abiotic conditions (low to subzero temperatures, anoxia) and the reduced abundance of fungi likely provide a niche for bacterial, facultative anaerobic decomposers of SOM such as members of the Actinobacteria, which were found in significantly higher relative abundances in buried than in unburied topsoils. Our study expands the knowledge on the microbial community structure in soils of Northern latitude permafrost regions, and attributes the delayed decomposition of SOM in buried soils to specific microbial taxa, and particularly to a decrease in abundance and activity of ECM fungi, and to the extent to which bacterial decomposers are able to act as their functional substitutes. PMID:24335828

Buried penis after newborn circumcision.

PubMed

Eroğlu, Egemen; Bastian, Okan W; Ozkan, Hilda C; Yorukalp, Ozlem E; Goksel, Ayla K

2009-04-01

Buried penis may develop after circumcision, mostly during infancy, presumably due to peripubic fat. A surgical approach may be recommended for psychological benefits to patients and parents, and because it is believed that this condition will not improve on its own with time. The aim of this study was to assess the natural history of buried penis after newborn circumcision. During a routine visit to the pediatrician infants with buried penis were assessed by a single pediatric surgeon between January 2004 and June 2007. In December 2007 all of these children were reexamined by the same pediatric surgeon and the natural growth of the genitalia was analyzed. A total of 88 infants were enrolled in the study. When they were first examined they were 3 to 6 months old (mean 3.3). In December 2007, after reexamination, patients were divided into groups based on age, including those younger than 1 year (14 patients), 1 to 3 years (59) and older than 3 years (15). The aspect of the genitalia was evaluated by the same pediatric surgeon for each patient. Buried penis was noted in 14 of 14 patients younger than 1 year (100%), 19 of 59 patients 1 to 3 years old (32.2%) and 1 of 15 patients older than 3 years (6.7%). Buried penis after newborn circumcision is not permanent. As infants get older, and after beginning to walk, the appearance usually turns out to be normal. This resolution may be due to growth and/or maturation alone. Based on our results, we do not recommend surgery for buried penis in children younger than 3 years.

Detection of thermally grown oxides in thermal barrier coatings by nondestructive evaluation

NASA Astrophysics Data System (ADS)

Fahr, A.; Rogé, B.; Thornton, J.

2006-03-01

The thermal-barrier coatings (TBC) sprayed on hot-section components of aircraft turbine engines commonly consist of a partially stabilized zirconia top-coat and an intermediate bond-coat applied on the metallic substrate. The bond-coat is made of an aluminide alloy that at high engine temperatures forms thermally grown oxides (TGO). Although formation of a thin layer of aluminum oxide at the interface between the ceramic top-coat and the bond-coat has the beneficial effect of protecting the metallic substrate from hot gases, oxide formation at splat boundaries or pores within the bond-coat is a source of weakness. In this study, plasma-sprayed TBC specimens are manufactured from two types of bond-coat powders and exposed to elevated temperatures to form oxides at the ceramic-bond-coat boundary and within the bond-coat. The specimens are then tested using nondestructive evaluation (NDE) and destructive metallography and compared with the as-manufactured samples. The objective is to determine if NDE can identify the oxidation within the bond-coat and give indication of its severity. While ultrasonic testing can provide some indication of the degree of bond-coat oxidation, the eddy current (EC) technique clearly identifies severe oxide formation within the bond-coat. Imaging of the EC signals as the function of probe location provides information on the spatial variations in the degree of oxidation, and thereby identifies which components or areas are prone to premature damage.

Displaced humeral lateral condyle fractures in children: should we bury the pins?

PubMed

Das De, Soumen; Bae, Donald S; Waters, Peter M

2012-09-01

The purpose of this investigation was to determine if leaving Kirschner wires exposed is more cost-effective than burying them subcutaneously after open reduction and internal fixation (ORIF) of humeral lateral condyle fractures. A retrospective cohort study of all lateral condyle fractures treated over a 10-year period at a single institution was performed. Data on surgical technique, fracture healing, and complications were analyzed, as well as treatment costs. A decision analysis model was then constructed to compare the strategies of leaving the pins exposed versus buried. Finally, sensitivity analyses were performed, assessing cost-effectiveness when infection rates and costs of treating deep infections were varied. A total of 235 children with displaced fractures were treated with ORIF using Kirschner wires. Pins were left exposed in 41 cases (17.4%) and buried in 194 cases (82.6%); the age, sex, injury mechanisms, and fracture patterns were similar in both the groups. The median time to removal of implants was shorter with exposed versus buried pins (4 vs. 6 wk, P<0.001), although there was no difference in fracture union or loss of reduction rates. The rate of superficial infection was higher with exposed pins (9.8% vs. 3.1%), but this was not statistically significant (P=0.076). There were no deep infections with exposed pins, whereas the rate of deep infection was 0.5% with buried pins (P=1.00). Buried pins were associated with additional complications, including symptomatic implants (7.2%); pins protruding through the skin (16%); internal pin migration necessitating additional surgery (1%); and skin necrosis (1%). The decision analysis revealed that leaving pins exposed resulted in an average cost savings of $3442 per patient. This strategy remained cost-effective even when infection rates with exposed pins approached 40%. Leaving the pins exposed after ORIF of lateral condyle fractures is safe and more cost-effective than burying the pins subcutaneously. Retrospective cohort study (level III).

Numerical modeling of magnetic moments for UXO applications

USGS Publications Warehouse

Sanchez, V.; Li, Y.; Nabighian, M.; Wright, D.

2006-01-01

The surface magnetic anomaly observed in UXO clearance is mainly dipolar and, consequently, the dipole is the only magnetic moment regularly recovered in UXO applications. The dipole moment contains information about intensity of magnetization but lacks information about shape. In contrast, higher-order moments, such as quadrupole and octupole, encode asymmetry properties of the magnetization distribution within the buried targets. In order to improve our understanding of magnetization distribution within UXO and non-UXO objects and its potential utility in UXO clearance, we present a 3D numerical modeling study for highly susceptible metallic objects. The basis for the modeling is the solution of a nonlinear integral equation describing magnetization within isolated objects. A solution for magnetization distribution then allows us to compute magnetic moments of the object, analyze their relationships, and provide a depiction of the surface anomaly produced by different moments within the object. Our modeling results show significant high-order moments for more asymmetric objects situated at depths typical of UXO burial, and suggest that the increased relative contribution to magnetic gradient data from these higher-order moments may provide a practical tool for improved UXO discrimination.

Relative importance of magnetic moments in UXO clearance applications

USGS Publications Warehouse

Sanchez, V.; Li, Y.; Nabighian, M.; Wright, D.

2006-01-01

Surface magnetic anomaly observed in UXO clearance is mainly dipolar and, as a result, the dipole is the only moment used regularly in UXO applications. The dipole moment contains intensity of magnetization information but lacks shape information. Unlike dipole, higher-order moments, such as quadrupole and octupole, encode asymmetry properties of magnetization distribution within buried targets. In order to improve our understanding of magnetization distribution within UXO and non-UXO objects and its potential utility in UXO clearance, we present results of a 3D numerical modeling study for highly susceptible metallic objects. The basis for modeling is the solution of a nonlinear integral equation, describing magnetization within isolated objects, allowing us to compute magnetic moments of the object, analyze their relationships, and provide a depiction of the surface anomaly produced by the different moments within the object. Our modeling results show significant high-order moments for more asymmetric objects situated at typical UXO burial depths, and suggest that the increased relative contribution to magnetic gradient data from these higher-order moments may provide a practical tool for improved UXO discrimination. ?? 2005 Society of Exploration Geophysicists.

Precision Optical Coatings for Large Space Telescope Mirrors

NASA Astrophysics Data System (ADS)

Sheikh, David

This proposal “Precision Optical Coatings for Large Space Telescope Mirrors” addresses the need to develop and advance the state-of-the-art in optical coating technology. NASA is considering large monolithic mirrors 1 to 8-meters in diameter for future telescopes such as HabEx and LUVOIR. Improved large area coating processes are needed to meet the future requirements of large astronomical mirrors. In this project, we will demonstrate a broadband reflective coating process for achieving high reflectivity from 90-nm to 2500-nm over a 2.3-meter diameter coating area. The coating process is scalable to larger mirrors, 6+ meters in diameter. We will use a battery-driven coating process to make an aluminum reflector, and a motion-controlled coating technology for depositing protective layers. We will advance the state-of-the-art for coating technology and manufacturing infrastructure, to meet the reflectance and wavefront requirements of both HabEx and LUVOIR. Specifically, we will combine the broadband reflective coating designs and processes developed at GSFC and JPL with large area manufacturing technologies developed at ZeCoat Corporation. Our primary objectives are to: Demonstrate an aluminum coating process to create uniform coatings over large areas with near-theoretical aluminum reflectance Demonstrate a motion-controlled coating process to apply very precise 2-nm to 5- nm thick protective/interference layers to large areas, Demonstrate a broadband coating system (90-nm to 2500-nm) over a 2.3-meter coating area and test it against the current coating specifications for LUVOIR/HabEx. We will perform simulated space-environment testing, and we expect to advance the TRL from 3 to >5 in 3-years.

Increased Reliability of Gas Turbine Components by Robust Coatings Manufacturing

NASA Astrophysics Data System (ADS)

Sharma, A.; Dudykevych, T.; Sansom, D.; Subramanian, R.

2017-08-01

The expanding operational windows of the advanced gas turbine components demand increasing performance capability from protective coating systems. This demand has led to the development of novel multi-functional, multi-materials coating system architectures over the last years. In addition, the increasing dependency of components exposed to extreme environment on protective coatings results in more severe penalties, in case of a coating system failure. This emphasizes that reliability and consistency of protective coating systems are equally important to their superior performance. By means of examples, this paper describes the effects of scatter in the material properties resulting from manufacturing variations on coating life predictions. A strong foundation in process-property-performance correlations as well as regular monitoring and control of the coating process is essential for robust and well-controlled coating process. Proprietary and/or commercially available diagnostic tools can help in achieving these goals, but their usage in industrial setting is still limited. Various key contributors to process variability are briefly discussed along with the limitations of existing process and product control methods. Other aspects that are important for product reliability and consistency in serial manufacturing as well as advanced testing methodologies to simplify and enhance product inspection and improve objectivity are briefly described.

Effect of Substrate Bias on Friction Coefficient, Adhesion Strength and Hardness of TiN-COATED Tool Steel

NASA Astrophysics Data System (ADS)

Hamzah, Esah; Ali, Mubarak; Toff, Mohd Radzi Hj. Mohd

In the present study, TiN coatings have been deposited on D2 tool steel substrates by using cathodic arc physical vapor deposition technique. The objective of this research work is to determine the usefulness of TiN coatings in order to improve the micro-Vickers hardness and friction coefficient of TiN coating deposited on D2 tool steel, which is widely used in tooling applications. A Pin-on-Disc test was carried out to study the coefficient of friction versus sliding distance of TiN coating deposited at various substrate biases. The standard deviation parameter during tribo-test result showed that the coating deposited at substrate bias of -75 V was the most stable coating. A significant increase in micro-Vickers hardness was recorded, when substrate bias was reduced from -150 V to zero. Scratch tester was used to compare the critical loads for coatings deposited at different bias voltages and the adhesion achievable was demonstrated with relevance to the various modes, scratch macroscopic analysis, critical load, acoustic emission and penetration depth. A considerable improvement in TiN coatings was observed as a function of various substrate bias voltages.

Comparison of higher-order multiphoton signal generation and collection at the 1700-nm window based on transmittance measurement of objective lenses.

PubMed

Wen, Wenhui; Wang, Yuxin; Liu, Hongji; Wang, Kai; Qiu, Ping; Wang, Ke

2018-01-01

One benefit of excitation at the 1700-nm window is the more accessible modalities of multiphoton signal generation. It is demonstrated here that the transmittance performance of the objective lens is of vital importance for efficient higher-order multiphoton signal generation and collection excited at the 1700-nm window. Two commonly used objective lenses for multiphoton microscopy (MPM) are characterized and compared, one with regular coating and the other with customized coating for high transmittance at the 1700-nm window. Our results show that, fourth harmonic generation imaging of mouse tail tendon and 5-photon fluorescence of carbon quantum dots using the regular objective lens shows an order of magnitude signal higher than those using the customized objective lens. Besides, the regular objective lens also enables a 3-photon fluorescence imaging depth of >1600 μm in mouse brain in vivo. Our results will provide guidelines for objective lens selection for MPM at the 1700-nm window. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Consideration of alternative designs for a Percutaneous Endoscopic Gastrostomy feeding tube

NASA Astrophysics Data System (ADS)

Yerrabolu, Santosh Rohit

The inability of some people to chew or swallow foods (but can digest foods) due to problems associated with various diseases and complications leads them to insufficient nutritional intake and loss of quality of life. These individuals are generally provided with nutritional support by means of injecting or infusing food directly into their stomachs or small intestines via feeding tubes. Gastrostomy feeding tubes (G-tubes) are used when such nutritional support is required for over 3-6 weeks. Percutaneous Endoscopic Gastrostomy (PEG) tubes are one of the most widely used G- Tubes and devices which are inserted via an incision through the abdominal wall either through a pull or push method. This investigation proposes conceptual alternative Percutaneous Endoscopy Gastrostomy (PEG) feeding tube designs with optimized materials selection to be used for their construction. The candidate materials were chosen from 18 commercial catheters, 2 reference grade polymers and a commercial polymer; using tissue-catheter-friction testing and surface chemistry characterization (Infrared spectroscopy and Critical Surface Tension approximation). The main objectives considered were to minimize slipping/dislodgement of gastrostomy tube/seal, to reduce peristomal leakage, and to attain size variability of PEG tubes while maintaining a low profile. Scanning Electron Microscope- Energy Dispersive X-ray Spectroscopy was employed to further determine the filler materials used in the samples. Nylon coated with fatty ester and filled with Barium sulphate was determined as the optimum material for the construction of the tube part of the feeding tubes to reduce slipping/dislodgment of gastrostomy tube/seal and to minimize peristomal leakage. Nylon coated with fatty ester and filled with Silica is the suggested as a candidate material for construction of the bumper/mushroom sections of the feeding tubes to avoid the Buried Bumper Syndrome. Fused Deposition Modeling, Selective Laser Sintering and/or 3-D printing are proposed for manufacturing of the product. Radio Frequency Glow Discharge Treatment is proposed as a sterilizing technique. Further investigations suggested are pilot Finite Element Analysis of the biomechanics involved and the subsequent validation and optimization of the conceptual designs apart from pursuing materials performance evaluation with stomach tissue-skin composites and long-term placement of tubes/ catheters at variable surface roughness profiles, filler materials, modulus of rigidities, tube-pull-through speeds and tissue stretch ratios.

Progress on determining the vapor signature of a buried land mine

NASA Astrophysics Data System (ADS)

George, Vivian; Jenkins, Thomas F.; Leggett, Daniel C.; Cragin, James H.; Phelan, James M.; Oxley, Jimmie C.; Pennington, Judy

1999-08-01

The goal of the DARPA 'Dog's Nose' program is to develop a sensor capable of detecting explosives contained in all buried landmines. In support of the DARPA program, the purpose of the Explosives Fate and Transport experiments is to define in detail the accessible trace chemical signature produced by the explosives contained in buried landmines. We intend to determine the partitioning, composition, and quantity of explosive related chemicals which emanate from different kinds of landmines buried in multiple soil types and exposed to various climatic events. We are also developing a computer model that will enable us to predict the composition and quantity of ERC under a much wider range of environmental conditions than we are able to test experimentally.

Brief description as of April, 1968, of the geology and hydrology of the Lake Minnequa area, Pueblo, Colorado, and suggested solutions for trouble caused by a high water table

USGS Publications Warehouse

Scott, Glenn R.

1972-01-01

Lake Minnequa lies in a poorly drained broad upland buried valley west of the valley of Salt Creek. Immediately north of Lake Minnequa the buried valley is sharply constricted in sees. 11 and 12, T. 21 S., R. 65 W., where it is entrenched in a buried ridge of bedrock (see geologic map).  The bedrock throughout the buried valley is composed of calcareous shale, limestone, and chalk of the Smoky Hill Shale Member of the Niobrara Formation.  These beds are relatively impermeable to the flow of ground water, but contribute large quantities of sodium sulfate to both the surface and ground water.

Life prediction and constitutive models for engine hot section anisotropic materials

NASA Technical Reports Server (NTRS)

Swanson, G. A.

1984-01-01

The development of directionally solidified and single crystal alloys is perhaps the most important recent advancement in hot section materials technology. The objective is to develop knowledge that enables the designer to improve anisotropic gas turbine parts to their full potential. Two single crystal alloys selected were PWA 1480 and Alloy 185. The coatings selected were an overlay coating, PWA 286, and an aluminide diffusion coating, PWA 273. The constitutive specimens were solid and cylindrical; the fatigue specimens were hollow and cylindrical. Two thicknesses of substrate are utilized. Specimens of both thickness (0.4 and 1.5 mm) will be coated and then tested for tensile, creep, and fatigue properties.

Optimisation and Validation of the ARAMIS Digital Image Correlation System for Use in Large-scale High-strain-rate Events

DTIC Science & Technology

2013-08-01

enamel paint. Under extreme plastic deformation, the relative deformation of the coating could cause the coating to separate resulting in loss of...point for one to be found. If a discontinuity, such as a crack , occurs through the object separating speckle pattern, then the strain data will only

Characterization of ZrO2-Y2O3 thermal spray powder systems

NASA Technical Reports Server (NTRS)

Mantkowski, Thomas E.; Rigney, David V.; Froning, Marc J.; Jayaraman, N.

1985-01-01

The overall objective is to establish the interrelation between the raw material in the coating process and the performance of the coating deposit. It is anticipated that these interrelations will help establish more precise specifications for the procurement of the raw materials. Some of the preliminary results of the program are presented.

A Novel Approach for Dry Powder Coating of Pellets with Ethylcellulose. Part II: Evaluation of Caffeine Release.

PubMed

Albertini, Beatrice; Melegari, Cecilia; Bertoni, Serena; Dolci, Luisa Stella; Passerini, Nadia

2018-04-01

The objective of this study was to assess the efficacy and the capability of a novel ethylcellulose-based dry-coating system to obtain prolonged and stable release profiles of caffeine-loaded pellets. Lauric and oleic acids at a suitable proportion were used to plasticize ethylcellulose. The effect of coating level, percentage of drug loading, inert core particle size, and composition of the coating formulation including the anti-sticking agent on the drug release profile were fully investigated. A coating level of 15% w/w was the maximum layered amount which could modify the drug release. The best controlled drug release was obtained by atomizing talc (2.5% w/w) together with the solid plasticizer during the dry powder-coating process. SEM pictures revealed a substantial drug re-crystallization on the pellet surface, and the release studies evidenced that caffeine diffused through the plasticized polymer acting as pore former. Therefore, the phenomenon of caffeine migration across the coating layer had a strong influence on the permeability of the coating membrane. Comparing dry powder-coated pellets to aqueous film-coated ones, drug migration happened during storage, though more sustained release profiles were obtained. The developed dry powder-coating process enabled the production of stable caffeine sustained release pellets. Surprisingly, the release properties of the dry-coated pellets were mainly influenced by the way of addition of talc into the dry powder-coating blend and by the drug nature and affinity to the coating components. It would be interesting to study the efficacy of novel coating system using a different API.

Effect of protective coating on microhardness of a new glass ionomer cement: Nanofilled coating versus unfilled resin

PubMed Central

Faraji, Foad; Heshmat, Haleh; Banava, Sepideh

2017-01-01

Background and Objectives: EQUIATM is a new gastrointestinal (GI) system with high compressive strength, surface microhardness (MH), and fluoride release potential. This in vitro study aimed to assess the effect of aging and type of protective coating on the MH of EQUIATM GI cement. Materials and Methods: A total of 30 disc-shaped specimens measuring 9 mm in diameter and 2 mm in thickness were fabricated of EQUIATM GI and divided into three groups of G-Coat nanofilled coating (a), no coating (b) and margin bond (c). The Vickers MH value of specimens was measured before (baseline) and at 3 and 6 months after water storage. Data were analyzed using repeated measures ANOVA. Results: Group B had significantly higher MH than the other two groups at baseline. Both G-Coat and margin bond increased the surface MH of GI at 3 and 6 months. The MH values of G-Coat and margin bond groups did not significantly increase or decrease between 3 and 6 months. Conclusion: The increase in MH was greater in the G-Coat compared to the margin bond group in the long-term. Clinically, margin bond may be a suitable alternative when G-Coat is not available. PMID:29259364

A Novel Method of Coating Orthodontic Archwires with Nanoparticles

PubMed Central

Syed, Shibli S; Kulkarni, Dinraj; Todkar, Rohit; Bagul, Ravikiran S; Parekh, Kreena; Bhujbal, Nikita

2015-01-01

Background: The major hazard to the orthodontic tooth movement is the friction developing at the bracket wire interface. In the past, there have been various attempts to reduce this friction. We believe that coating the commercially available orthodontic wires with nanoparticles can result in a successful reduction of this friction. The objective of this study is to develop a novel method of coating orthodontic archwires with nanoparticles. Materials and Methods: Stainless steel (Ormco, CA, USA), titanium molybdenum alloy (Ormco, CA, USA) and nickel-titanium (G and H Wire Company, USA) orthodontic wires with a rectangular cross-section dimension of 0.019”× 0.025”, were selected. The wires were later coated with a uniform and smooth nanoparticle film using 100 ml nanocremics. The coating procedure described in this article is a sol-gel thin film dip coating method. Results: The coating procedure was verified by comparing the surface topography of nanocoated archwires with the commercially available archwires in an environmental scanning electron microscope (ESEM). The ESEM images prove that the surface topography of the coated wires was found to be smoother with less surface deteriorations as compared to the commercially available wires. Conclusion: Commercially available orthodontic wires can be successfully coated using a novel method of sol-gel thin film dip coating method. PMID:26028899

Instrumenting free-swimming dolphins echolocating in open water.

PubMed

Martin, Stephen W; Phillips, Michael; Bauer, Eric J; Moore, Patrick W; Houser, Dorian S

2005-04-01

Dolphins within the Navy Marine Mammal Program use echolocation to effectively locate underwater mines. They currently outperform manmade systems at similar tasks, particularly in cluttered environments and on buried targets. In hopes of improving manmade mine-hunting sonar systems, two instrumentation packages were developed to monitor free-swimming dolphin motion and echolocation during open-water target detection tasks. The biosonar measurement tool (BMT) is carried by a dolphin and monitors underwater position and attitude while simultaneously recording echolocation clicks and returning echoes through high-gain binaural receivers. The instrumented mine simulator (IMS) is a modified bottom target that monitors echolocation signals arriving at the target during ensonification. Dolphin subjects were trained to carry the BMT in open-bay bottom-object target searches in which the IMS could serve as a bottom object. The instrumentation provides detailed data that reveal hereto-unavailable information on the search strategies of free-swimming dolphins conducting open-water, bottom-object search tasks with echolocation.

Instrumenting free-swimming dolphins echolocating in open water

NASA Astrophysics Data System (ADS)

Martin, Stephen W.; Phillips, Michael; Bauer, Eric J.; Moore, Patrick W.; Houser, Dorian S.

2005-04-01

Dolphins within the Navy Marine Mammal Program use echolocation to effectively locate underwater mines. They currently outperform manmade systems at similar tasks, particularly in cluttered environments and on buried targets. In hopes of improving manmade mine-hunting sonar systems, two instrumentation packages were developed to monitor free-swimming dolphin motion and echolocation during open-water target detection tasks. The biosonar measurement tool (BMT) is carried by a dolphin and monitors underwater position and attitude while simultaneously recording echolocation clicks and returning echoes through high-gain binaural receivers. The instrumented mine simulator (IMS) is a modified bottom target that monitors echolocation signals arriving at the target during ensonification. Dolphin subjects were trained to carry the BMT in open-bay bottom-object target searches in which the IMS could serve as a bottom object. The instrumentation provides detailed data that reveal hereto-unavailable information on the search strategies of free-swimming dolphins conducting open-water, bottom-object search tasks with echolocation. .

Petamenophis (Padiamenemipet), an Egyptian Child Mummy Protected for Eternity: Revelation by Multidetector Computed Tomography.

PubMed

Martina, Maria Cristina; Cesarani, Federico; Boano, Rosa; Fiore Marochetti, Elisa; Gandini, Giovanni

The objective of our work was to report the most recent findings obtained with multidetector computed tomography of a child mummy from the Roman period (119-123 CE) housed at the Egyptian Museum in Turin, Italy. Multidetector computed tomography and postprocessing were applied to understand the embalming techniques, the nature of a foreign object, and anthropometrical values. The information was compared with that from other mummies that were buried in the same tomb, but today housed in different museums. New information regarding the embalming technique was revealed. Multidetector computed tomography allowed the identification of a knife-like metallic object, probably an amulet for the child's protection in the afterlife. Multidetector computed tomography and image postprocessing confirm their valuable role in noninvasive studies in ancient mummies and provided evidence of a unique cultural practice in the late history of Ancient Egypt such as placing a knife possibly as an amulet.

Laying Futility to Rest

PubMed Central

Nair-Collins, Michael

2015-01-01

In this essay I examine the formal structure of the concept of futility, enabling identification of the appropriate roles played by patient, professional, and society. I argue that the concept of futility does not justify unilateral decisions to forego life-sustaining medical treatment over patient or legitimate surrogate objection, even when futility is determined by a process or subject to ethics committee review. Furthermore, I argue for a limited positive ethical obligation on the part of health care professionals to assist patients in achieving certain restricted goals, including the preservation of life, even in circumstances in which most would agree that that life is of no benefit to the patient. Finally, I address the objection that professional integrity overrides this limited obligation and find the objection unconvincing. In short, my aim in this essay is to see the concept of futility finally buried, once and for all. PMID:26232595

Detection of explosive remnants of war by neutron thermalisation.

PubMed

Brooks, F D; Drosg, M; Smit, F D; Wikner, C

2012-01-01

The HYDAD-D landmine detector (Brooks and Drosg, 2005) has been modified and field-tested for 17 months in a variety of soil conditions. Test objects containing about the same mass of hydrogen (20g) as small explosive remnants of war, such as antipersonnel landmines, were detected with efficiency 100% when buried at cover depths up to 10cm. The false alarm rate under the same conditions was 9%. Plots of detection efficiency versus false alarm rate are presented. Copyright © 2011 Elsevier Ltd. All rights reserved.

Detection of leaks in buried rural water pipelines using thermal infrared images

USGS Publications Warehouse

Eidenshink, Jeffery C.

1985-01-01

Leakage is a major problem in many pipelines. Minor leaks called 'seeper leaks', which generally range from 2 to 10 m3 per day, are common and are difficult to detect using conventional ground surveys. The objective of this research was to determine whether airborne thermal-infrared remote sensing could be used in detecting leaks and monitoring rural water pipelines. This study indicates that such leaks can be detected using low-altitude 8.7- to 11.5. micrometer wavelength, thermal infrared images collected under proper conditions.

Evaluation of preparation methods for suspended nano-objects on substrates for dimensional measurements by atomic force microscopy

PubMed Central

Göhler, Daniel; Wessely, Benno; Stintz, Michael; Lazzerini, Giovanni Mattia; Yacoot, Andrew

2017-01-01

Dimensional measurements on nano-objects by atomic force microscopy (AFM) require samples of safely fixed and well individualized particles with a suitable surface-specific particle number on flat and clean substrates. Several known and proven particle preparation methods, i.e., membrane filtration, drying, rinsing, dip coating as well as electrostatic and thermal precipitation, were performed by means of scanning electron microscopy to examine their suitability for preparing samples for dimensional AFM measurements. Different suspensions of nano-objects (with varying material, size and shape) stabilized in aqueous solutions were prepared therefore on different flat substrates. The drop-drying method was found to be the most suitable one for the analysed suspensions, because it does not require expensive dedicated equipment and led to a uniform local distribution of individualized nano-objects. Traceable AFM measurements based on Si and SiO2 coated substrates confirmed the suitability of this technique. PMID:28904839

Evaluation of preparation methods for suspended nano-objects on substrates for dimensional measurements by atomic force microscopy.

PubMed

Fiala, Petra; Göhler, Daniel; Wessely, Benno; Stintz, Michael; Lazzerini, Giovanni Mattia; Yacoot, Andrew

2017-01-01

Dimensional measurements on nano-objects by atomic force microscopy (AFM) require samples of safely fixed and well individualized particles with a suitable surface-specific particle number on flat and clean substrates. Several known and proven particle preparation methods, i.e., membrane filtration, drying, rinsing, dip coating as well as electrostatic and thermal precipitation, were performed by means of scanning electron microscopy to examine their suitability for preparing samples for dimensional AFM measurements. Different suspensions of nano-objects (with varying material, size and shape) stabilized in aqueous solutions were prepared therefore on different flat substrates. The drop-drying method was found to be the most suitable one for the analysed suspensions, because it does not require expensive dedicated equipment and led to a uniform local distribution of individualized nano-objects. Traceable AFM measurements based on Si and SiO 2 coated substrates confirmed the suitability of this technique.

The Vertical Distribution of Buried Volatiles at the Moon revealed by Thermal and Epithermal Neutron Fluxes from LEND Observations

NASA Astrophysics Data System (ADS)

Chin, G.; Sagdeev, R.; Su, J. J.; Murray, J.; Livengood, T. A.

2015-12-01

Determining the quantity and vertical distribution of volatile species on and below the surface of planetary bodies is vital to understand the primordial chemical inventory and subsequent evolution of planets. Volatiles may provide resources to support future human exploration. This is particularly true for the Moon, which is well observed by many methods from ground-based, lunar orbit, and in situ, and is an accessible destination or way station for human exploration. We present Geant4 models of relative fluxes of Fast, Epithermal, and Thermal neutron emission generated in a planetary regolith by galactic cosmic rays to reveal the first 1-2 meters vertical structure of embedded hydrogen or water. Varying ratios of Thermal versus Epithermal, low-energy-Epithermal versus high-energy-Epithermal, and Thermal versus Fast neutron emissions are diagnostics of the depth in which hydrogen/water layers are buried within the top 1-2 meters of the regolith. In addition, we apply model calculations to Lunar Exploration Neutron Detector (LEND) thermal and epithermal data, acquired on the Lunar Reconnaissance Orbiter (LRO), in specific regions of the Moon to retrieve the vertical distribution of buried ice from the remote sensing information. GEANT4 is a set of particle physics transport simulation codes that exploits object-oriented software methods to deliver a comprehensive and flexible toolkit that is modular and extensible, based on a free open-source development model. GEANT4 has become a standard tool to simulate applications as diverse as particle telescope and detector response, space radiation shielding and optimization, total ionizing dose in spacecraft components, and biological effects of radiation.

Stable White Coatings

NASA Technical Reports Server (NTRS)

Zerlaut, Gene A.; Gilligan, J. E.; Harada, Y.

1965-01-01

In a previous research program for the Jet Propulsion- Laboratory, extensive studies led to the development and specifications of three zinc oxide-pigmented thermal-control coatings. The principal objectives of this program are: improvement of the three paints (as engineering materials), determination of the validity of our accelerated space-simulation testing, and continuation of the zinc oxide photolysis studies begun in the preceding program. Specific tasks that are discussed include: improvement of potassium silicate coatings as engineering materials and elucidation of their storage and handling problems; improvement of methyl silicone coatings as engineering materials; studies of zinc oxide photolysis to establish reasons for the observed stability of zinc oxide; and determination of space-simulation parameters such as long-term stability (to 8000 ESH), effect of coating surface temperature on the rate of degradation, and validity of accelerated testing (by reciprocity and wavelength dependency studies).

Porcelain-coated antenna for radio-frequency driven plasma source

DOEpatents

Leung, K.N.; Wells, R.P.; Craven, G.E.

1996-12-24

A new porcelain-enamel coated antenna creates a clean plasma for volume or surface-conversion ion sources. The porcelain-enamel coating is hard, electrically insulating, long lasting, non fragile, and resistant to puncture by high energy ions in the plasma. Plasma and ion production using the porcelain enamel coated antenna is uncontaminated with filament or extraneous metal ions because the porcelain does not evaporate and is not sputtered into the plasma during operation. Ion beams produced using the new porcelain-enamel coated antenna are useful in ion implantation, high energy accelerators, negative, positive, or neutral beam applications, fusion, and treatment of chemical or radioactive waste for disposal. For ion implantation, the appropriate species ion beam generated with the inventive antenna will penetrate large or small, irregularly shaped conducting objects with a narrow implantation profile. 8 figs.

Performance of 40-millimeter-bore ball bearings with lead- and lead-alloy-plated retainers in liquid hydrogen at 1.2 million DN

NASA Technical Reports Server (NTRS)

Brewe, D. E.; Wisander, D. W.; Scribbe, H. W.

1972-01-01

Forty-millimeter-bore ball bearings with lead- and lead-alloy-coated retainers were operated in liquid hydrogen at 30,000 rpm under a thrust load of 1780 N (400 lb.) Four different substrate materials were used for the retainer. Longer bearing run times were achieved with a lead-tin-copper alloy coating plated onto a leaded-bronze material (22.5 hr) and an aluminum-bronze alloy (19.3 hr). One bearing with a pure lead coating achieved the desired objective of 10 hr. This bearing had an aluminum - bronze substrate retainer and ran successfully for 12.4 hr. Additions of antimony to the lead provided an alloy coating with better wear resistance than pure lead; however, this coating was abrasive to the outer-race lands.

Distribution of ancient carbon in buried soils in an eroding loess landscape

NASA Astrophysics Data System (ADS)

Szymanski, L. M.; Mason, J. A.; De Graaff, M. A.; Berhe, A. A.; Marin-Spiotta, E.

2017-12-01

Understanding the processes that contribute to the accumulation and loss of carbon in soils and the implications for land management is vital for mitigating climate change. Buried soils or paleosols that represent former surface horizons can store more organic carbon than mineral horizons at equivalent depths due to burial restricting microbial decomposition. The presence of buried soils defies modeled expectations of exponential declines in carbon concentrations with depth, especially in locations where successive depositional events lead to multiple buried soil layers. Buried soils are found in a diversity of depositional environments across latitudes and without accounting for their presence can lead to underestimates of regional carbon reservoirs. Here we present data on the spatial distribution of carbon in a paleosol loess sequence in Nebraska, focusing on one prominent paleosol, the Brady soil. The Brady soil has been identified throughout the Central Great Plains and began developing at the end of the Pleistocene and was subsequently buried by loess in the early Holocene (Mason et al. 2003). Preliminary analyses of the Brady soil at its deepest, 6-m below the surface, reveal large differences in the composition and degree of decomposition of organic matter from the modern soil. We sampled along burial and erosional transects to characterize spatial variability in the depth of Brady soil from the modern landscape surface and to determine how these differences may alter the amount and composition of organic carbon. A more accurate determination of the spatial extent and heterogeneity of buried soil carbon will improve regional estimates of carbon reservoirs. This assessment of its variability across the landscape will inform future planned work on the vulnerability of ancient carbon to disturbance.

Understanding the Adsorption Interface of Polyelectrolyte Coating on Redox Active Nanoparticles Using Soft Particle Electrokinetics and Its Biological Activity

PubMed Central

2015-01-01

The application of cerium oxide nanoparticles (CNPs) for therapeutic purposes requires a stable dispersion of nanoparticles in a biological environment. The objective of this study is to tailor the properties of polyelectrolyte coated CNPs as a function of molecular weight to achieve a stable and catalytic active dispersion. The coating of CNPs with polyacrylic acid (PAA) has increased the dispersion stability of CNPs and enhanced the catalytic ability. The stability of PAA coating was analyzed using the change in the Gibbs free energy computed by the Langmuir adsorption model. The adsorption isotherms were determined using soft particle electrokinetics which overcomes the challenges presented by other techniques. The change in Gibbs free energy was highest for CNPs coated with PAA of 250 kg/mol indicating the most stable coating. The change in free energy for PAA of 100 kg/mol coated CNPs was 85% lower than the PAA of 250 kg/mol coated CNPs. This significant difference is caused by the strong adsorption of PAA of 100 kg/mol on CNPs. Catalytic activity of PAA-CNPs is assessed by the catalase enzymatic mimetic activity of nanoparticles. The catalase activity was higher for PAA coated CNPs as compared to bare CNPs which indicated preferential adsorption of hydrogen peroxide induced by coating. This indicates that the catalase activity is also affected by the structure of the coating layer. PMID:24673655

Pseudoephedrine hydrochloride sustained-release pellets prepared by a combination of hot-melt subcoating and polymer coating.

PubMed

Yang, Zi Yi; Lu, Yan; Tang, Xing

2008-12-01

Pseudoephedrine hydrochloride is an active very highly water soluble substance. In order to control release of a drug with this property, we developed the application of a combination of hot-melt subcoating and polymer coating was developed. The main objective was to investigate the influence of this combination on the release of highly water soluble drug and how it works. Hot-melt subcoating was achieved by using a coating pan. Subsequently, the outer polymer coating was prepared by fluidized bed, and the drug release was determined by high-performance liquid chromatograph (HPLC) method. Hot-melt subcoating can form a barrier between the drug-loaded pellets and the polymer coating layer, which prevents migration of the drug during film application. Consequently, the level of polymer coating can be reduced significantly, and the effectiveness of the polymer coating increased. In this study, the release profile of pellets with a 10% hot-melt subcoating and 5% polymer coating weight gain met the dissolution requirement of USP29 for pseudoephedrine hydrochloride extended-release capsules. Compared with pellets only polymer coated (10% level), the polymer coating level of pellets prepared by this technology was reduced by half due to hot-melt subcoating. By means of this hot-melt subcoating and polymer coating, sustained-release pellets containing pseudoephedrine hydrochloride were successfully prepared.

Molecular plasma deposition: biologically inspired nanohydroxyapatite coatings on anodized nanotubular titanium for improving osteoblast density

PubMed Central

Balasundaram, Ganesan; Storey, Daniel M; Webster, Thomas J

2015-01-01

In order to begin to prepare a novel orthopedic implant that mimics the natural bone environment, the objective of this in vitro study was to synthesize nanocrystalline hydroxyapatite (NHA) and coat it on titanium (Ti) using molecular plasma deposition (MPD). NHA was synthesized through a wet chemical process followed by a hydrothermal treatment. NHA and micron sized hydroxyapatite (MHA) were prepared by processing NHA coatings at 500°C and 900°C, respectively. The coatings were characterized before and after sintering using scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The results revealed that the post-MPD heat treatment of up to 500°C effectively restored the structural and topographical integrity of NHA. In order to determine the in vitro biological responses of the MPD-coated surfaces, the attachment and spreading of osteoblasts (bone-forming cells) on the uncoated, NHA-coated, and MHA-coated anodized Ti were investigated. Most importantly, the NHA-coated substrates supported a larger number of adherent cells than the MHA-coated and uncoated substrates. The morphology of these cells was assessed by scanning electron microscopy and the observed shapes were different for each substrate type. The present results are the first reports using MPD in the framework of hydroxyapatite coatings on Ti to enhance osteoblast responses and encourage further studies on MPD-based hydroxyapatite coatings on Ti for improved orthopedic applications. PMID:25609958

A synthetic mimic of protein inner space: buried polar interactions in a deep water-soluble host.

PubMed

Butterfield, Sara M; Rebek, Julius

2006-12-06

A deep water-soluble cavitand was functionalized with a carboxylic acid directed toward the hydrophobic interior of the host. The buried salt-bridge interaction formed with a quinuclidium cationic guest was determined to be worth -3 kcal/mol using a free energy cycle. The strength of the interaction correlates well with buried salt bridges in proteins, indicating that the cavitand interior mimics the hydrophobic inner space of proteins.

Effect of antimony incorporation on the density, shape, and luminescence of InAs quantum dots

NASA Astrophysics Data System (ADS)

Chen, J. F.; Chiang, C. H.; Wu, Y. H.; Chang, L.; Chi, J. Y.

2008-07-01

This work investigates the surfactant effect on exposed and buried InAs quantum dots (QDs) by incorporating Sb into the QD layers with various Sb beam equivalent pressures (BEPs). Secondary ion mass spectroscopy shows the presence of Sb in the exposed and buried QD layers with the Sb intensity in the exposed layer substantially exceeding that in the buried layer. Incorporating Sb can reduce the density of the exposed QDs by more than two orders of magnitude. However, a high Sb BEP yields a surface morphology with a regular periodic structure of ellipsoid terraces. A good room-temperature photoluminescence (PL) at ˜1600 nm from the exposed QDs is observed, suggesting that the Sb incorporation probably improves the emission efficiency by reducing the surface recombination velocity at the surface of the exposed QDs. Increasing Sb BEP causes a blueshift of the emission from the exposed QDs due to a reduction in the dot height as suggested by atomic force microscopy. Increasing Sb BEP can also blueshift the ˜1300 nm emission from the buried QDs by decreasing the dot height. However, a high Sb BEP yields a quantum well-like PL feature formed by the clustering of the buried QDs into an undulated planar layer. These results indicate a marked Sb surfactant effect that can be used to control the density, shape, and luminescence of the exposed and buried QDs.

Interfacial stability of CoSi2/Si structures grown by molecular beam epitaxy

NASA Technical Reports Server (NTRS)

George, T.; Fathauer, R. W.

1992-01-01

The stability of CoSi2/Si interfaces was examined in this study using columnar silicide structures grown on (111) Si substrates. In the first set of experiments, Co and Si were codeposited using MBE at 800 C and the resulting columnar silicide layer was capped by epitaxial Si. Deposition of Co on the surface of the Si capping layer at 800 C results in the growth of the buried silicide columns. The buried columns grow by subsurface diffusion of the deposited Co, suppressing the formation of surface islands of CoSi2. The column sidewalls appear to be less stable than the top and bottom interfaces, resulting in preferential lateral growth and ultimately in the coalescence of the columns to form a continuous buried CoSi2 layer. In the second set of experiments, annealing of a 250 nm-thick buried columnar layer at 1000 C under a 100 nm-thick Si capping layer results in the formation of a surface layer of CoSi2 with a reduction in the sizes of the CoSi2 columns. For a sample having a thicker Si capping layer the annealing leads to Ostwald ripening producing buried equiaxed columns. The high CoSi2/Si interfacial strain could provide the driving force for the observed behavior of the buried columns under high-temperature annealing.

Post-weaning social isolation increases activity in a novel environment but decreases defensive burying and subchronic MK-801 enhances the activity but not the burying effect in rats.

PubMed

Simpson, Sarah M; Menard, Janet L; Reynolds, James N; Beninger, Richard J

2010-03-01

Subchronic treatment with a non-competitive glutamate NMDA-receptor antagonist [e.g., MK-801 or phencyclidine] or social isolation (SI) from weaning (age 21 days) to adulthood (age 56 days) produce deficits similar to some of the positive and negative symptoms of schizophrenia. Few studies have evaluated the effects of these treatments on emotional behavior. We hypothesized that subchronic MK-801, post-weaning SI or the two in combination would alter activity in a novel environment, anxiety-like behaviors in the elevated plus-maze, coping responses in the defensive burying paradigm and social behavior. In experiment 1, SI rats (n=17) showed increased locomotor activity when exposed to a novel environment, no change in plus-maze behavior and decreased defensive burying when compared to group housed rats (n=16). Subchronic MK-801 enhanced the increase in activity but not the decrease in burying in SI rats. Experiment 2 evaluated the effects on social behavior of post-weaning SI. The locomotor and burying results of experiment 1 were replicated and SI rats (n=9) were found to decrease orientation towards a novel conspecific social target when compared to group housed rats (n=8). The behavioral abnormalities of SI rats may be a manifestation of GABAergic dysfunction that has recently become evident in schizophrenia. (c) 2009 Elsevier Inc. All rights reserved.

a Uav Based 3-D Positioning Framework for Detecting Locations of Buried Persons in Collapsed Disaster Area

NASA Astrophysics Data System (ADS)

Moon, H.; Kim, C.; Lee, W.

2016-06-01

Regarding spatial location positioning, indoor location positioning theories based on wireless communication techniques such as Wi-Fi, beacon, UWB and Bluetooth has widely been developing across the world. These techniques are mainly focusing on spatial location detection of customers using fixed wireless APs and unique Tags in the indoor environment. Besides, since existing detection equipment and techniques using ultrasound or sound etc. to detect buried persons and identify survival status for them cause 2nd damages on the collapsed debris for rescuers. In addition, it might take time to check the buried persons. However, the collapsed disaster sites should consider both outdoor and indoor environments because empty spaces under collapsed debris exists. In order to detect buried persons from the empty spaces, we should collect wireless signals with Wi-Fi from their mobile phone. Basically, the Wi-Fi signal measure 2-D location. However, since the buried persons have Z value with burial depth, we also should collect barometer sensor data from their mobile phones in order to measure Z values according to weather conditions. Specially, for quick accessibility to the disaster area, a drone (UAV; Unmanned Arial Vehicle) system, which is equipped with a wireless detection module, was introduced. Using these framework, this study aims to provide the rescuers with effective rescue information by calculating 3-D location for buried persons based on the wireless and barometer sensor fusion.

Hematite-coated microfossils: primary ecological fingerprint or taphonomic oddity of the Paleoproterozoic?

PubMed

Shapiro, R S; Konhauser, K O

2015-05-01

Microfossils belonging to the 1.88-billion-year-old 'Gunflint-biota' are preserved as carbonaceous and hematitic filaments and spheres that are believed to represent ancient chemolithoautotrophic Fe(II) oxidizing bacteria that grew above a chemocline where ferruginous seawater upwelled into shallow, oxygenated waters. This 'biological' model posits that hematite formed during burial from dewatering of the precursor ferric oxyhydroxides that encrusted Fe(II)-oxidizing bacteria. Here, we present an alternate 'taphonomic' model in which iron-rich groundwaters discharged into buried stromatolites; thus, the mineralization reactions are more informative of diagenetic processes than they are for primary marine conditions. We sampled centimeter-scale columnar stromatolites from both the lower and upper stromatolite horizons of the Biwabik and Gunflint formations, across a range of metamorphic gradients including unaltered to prehnite-pumpellyite taconite, supergene altered ore, and amphibolite-pyroxene grade contact-metamorphic zones. Fossils are rare to very rare and comprise curved filaments that exist in clusters with similar orientations. The filaments from throughout the Biwabik are similar to well-preserved carbonaceous Gunflintia from Ontario. Spheres of Huroniospora are also found in both formations. Microfossils from the least altered sections are preserved as carbon. Prehnite-pumpellyite samples are composed of either carbon or hematite (Fe2 O3 ). Within the contact aureole, filaments are densely coated by magnetite (Fe3 O4 ); the highest grade samples are secondarily oxidized to martite. The consistency in stromatolite microstructure and lithofacies throughout the metamorphic grades suggests they formed under similar environmental conditions. Post-depositional alteration led to replacement of the carbon by iron oxide. The facies association, filament distribution, and lack of branching and attached spherical cells argue against Gunflintia being a direct analogue to common marine, chemolithoautotrophic Fe(II)-oxidizing bacteria. Instead, we propose that the presence of hematite-coated microfossils is a reflection of taphonomic processes and does not necessarily reflect the byproduct of an original microbial ecosystem. © 2015 John Wiley & Sons Ltd.

Revealing the semiconductor–catalyst interface in buried platinum black silicon photocathodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aguiar, Jeffery A.; Anderson, Nicholas C.; Neale, Nathan R.

2016-01-01

Nanoporous 'black' silicon semiconductors interfaced with buried platinum nanoparticle catalysts have exhibited stable activity for photoelectrochemical hydrogen evolution even after months of exposure to ambient conditions. The mechanism behind this stability has not been explained in detail, but is thought to involve a Pt/Si interface free from SiOx layer that would adversely affect interfacial charge transfer kinetics. In this paper, we resolve the chemical composition and structure of buried Pt/Si interfaces in black silicon photocathodes from a micron to sub-nanometer level using aberration corrected analytical scanning transmission electron microscopy. Through a controlled electrodeposition of copper on samples aged for onemore » month in ambient conditions, we demonstrate that the main active catalytic sites are the buried Pt nanoparticles located below the 400-800 nm thick nanoporous SiOx layer. Though hydrogen production performance degrades over 100 h under photoelectrochemical operating conditions, this burying strategy preserves an atomically clean catalyst/Si interface free of oxide or other phases under air exposure and provides an example of a potential method for stabilizing silicon photoelectrodes from oxidative degradation in photoelectrochemical applications.« less

Feasibility of fast neutron analysis for the detection of explosives buried in soil

NASA Astrophysics Data System (ADS)

Faust, A. A.; McFee, J. E.; Bowman, C. L.; Mosquera, C.; Andrews, H. R.; Kovaltchouk, V. D.; Ing, H.

2011-12-01

A commercialized thermal neutron analysis (TNA) sensor has been developed to confirm the presence of buried bulk explosives as part of a multi-sensor anti-tank landmine detection system. Continuing improvements to the TNA system have included the use of an electronic pulsed neutron generator that offers the possibility of applying fast neutron analysis (FNA) methods to improve the system's detection capability. This paper describes an investigation into the use of FNA as a complementary component in such a TNA system. The results of a modeling study using simple geometries and a full model of the TNA sensor head are presented, as well as preliminary results from an experimental associated particle imaging (API) system that supports the modeling study results. The investigation has concluded that the pulsed beam FNA approach would not improve the detection performance of a TNA system for landmine or buried IED detection in a confirmation role, and could not be made into a practical stand-alone detection system for buried anti-tank landmines. Detection of buried landmines and IEDs by FNA remains a possibility, however, through the use of the API technique.

Metrology for Fuel Cell Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stocker, Michael; Stanfield, Eric

2015-02-04

The project was divided into three subprojects. The first subproject is Fuel Cell Manufacturing Variability and Its Impact on Performance. The objective was to determine if flow field channel dimensional variability has an impact on fuel cell performance. The second subproject is Non-contact Sensor Evaluation for Bipolar Plate Manufacturing Process Control and Smart Assembly of Fuel Cell Stacks. The objective was to enable cost reduction in the manufacture of fuel cell plates by providing a rapid non-contact measurement system for in-line process control. The third subproject is Optical Scatterfield Metrology for Online Catalyst Coating Inspection of PEM Soft Goods. Themore » objective was to evaluate the suitability of Optical Scatterfield Microscopy as a viable measurement tool for in situ process control of catalyst coatings.« less

47 CFR 32.2423 - Buried cable.

Code of Federal Regulations, 2010 CFR

2010-10-01

... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2423 Buried cable. (a... of cleaning manholes and ducts in connection with construction work and the cost of permits and...

Distribution of Large Visible and Buried Impact Basins on Mars: Comparison with Free-Air Gravity, Crustal Thickness and Magnetization Models

NASA Technical Reports Server (NTRS)

Frey, H. V.

2004-01-01

A comparison of the distribution of visible and buried impact basins (Quasi-Circular Depressions or QCDs) on Mars > 200 km in diameter with free air gravity, crustal thickness and magnetization models shows some QCDs have coincident gravity anomalies but most do not. Very few QCDs have closely coincident magnetization anomalies, and only the oldest of the very large impact basins have strong magnetic anomalies within their main rings. Crustal thickness data show a large number of Circular Thinned Areas (CTAs). Some of these correspond to known impact basins, while others may represent buried impact basins not always recognized as QCDs in topography data alone. If true, the buried lowlands may be even older than we have previously estimated.

Dip coating process: Silicon sheet growth development for the large-area silicon sheet task of the low-cost silicon solar array project

NASA Technical Reports Server (NTRS)

Heaps, J. D.; Maciolek, R. B.; Zook, J. D.; Harrison, W. B.; Scott, M. W.; Hendrickson, G.; Wolner, H. A.; Nelson, L. D.; Schuller, T. L.; Peterson, A. A.

1976-01-01

The technical and economic feasibility of producing solar cell quality sheet silicon by dip-coating one surface of carbonized ceramic substrates with a thin layer of large grain polycrystalline silicon was investigated. The dip-coating methods studied were directed toward a minimum cost process with the ultimate objective of producing solar cells with a conversion efficiency of 10% or greater. The technique shows excellent promise for low cost, labor-saving, scale-up potentialities and would provide an end product of sheet silicon with a rigid and strong supportive backing. An experimental dip-coating facility was designed and constructed, several substrates were successfully dip-coated with areas as large as 25 sq cm and thicknesses of 12 micron to 250 micron. There appears to be no serious limitation on the area of a substrate that could be coated. Of the various substrate materials dip-coated, mullite appears to best satisfy the requirement of the program. An inexpensive process was developed for producing mullite in the desired geometry.

Low earth orbit durability of protected silicone for refractive photovoltaic concentrator arrays

NASA Technical Reports Server (NTRS)

McCollum, Timothy A.; deGroh, Kim K.

1995-01-01

Photovoltaic power systems with novel refractive silicone solar concentrators are being developed for use in low Earth orbit (LEO). Because of the vulnerability of silicones to atomic oxygen and ultraviolet radiation, these lenses are coated with a multilayer metal oxide protective coating. The objective of this work was to evaluate the effects of atomic oxygen and thermal exposures on multilayer coated silicone. Samples were exposed to high-fluence ground-laboratory and low-fluence in-space atomic oxygen. Ground testing resulted in decreases in both total and specular transmittance, while in-space exposure resulted in only small decreases in specular transmittance. A contamination film, attributed to exposed silicone at coating crack sites, was found to cause transmittance decreases during ground testing. Propagation of coating cracks was found to be the result of sample heating during exposure. The potential for silicone exposure, with the resulting degradation of optical properties from silicone contamination, indicates that this multilayer coated silicone is not durable for LEO space applications where thermal exposures will cause coating crack development and propagation.

Thick thermal barrier coatings for diesel engines

NASA Technical Reports Server (NTRS)

Beardsley, M. Brad

1995-01-01

Caterpillar's approach to applying thick thermal barrier coatings (TTBC's) to diesel engine combustion chambers has been to use advanced modeling techniques to predict engine conditions and combine this information with fundamental property evaluation of TTBC systems to predict engine performance and TTBC stress states. Engine testing has been used to verify the predicted performance of the TTBC systems and provide information on failure mechanisms. The objective Caterpillar's program to date has been to advance the fundamental understanding of thick thermal barrier coating systems. Previous reviews of thermal barrier coating technology concluded that the current level of understanding of coating system behavior is inadequate and the lack of fundamental understanding may impeded the application of TTBC's to diesel engines. Areas of TTBC technology being examined in this program include powder characteristics and chemistry; bond coat composition; coating design, microstructure, and thickness as they affect properties, durability, and reliability; and TTBC 'aging' effects (microstructural and property changes) under diesel engine operating conditions. Methods to evaluate the reliability and durability of TTBC's have been developed that attempt to understand the fundamental strength of TTBC's for particular stress states.

Thick thermal barrier coatings for diesel engines

NASA Technical Reports Server (NTRS)

Beardsley, M. B.

1995-01-01

Caterpillar's approach to applying Thick Thermal Barrier Coatings (TTBC's) to diesel engine combustion chambers has been to use advanced modeling techniques to predict engine conditions and combine this information with fundamental property evaluation of TTBC systems to predict engine performance and TTBC stress states. Engine testing has been used to verify the predicted performance of the TTBC systems and provide information on failure mechanisms. The objective of Caterpillar's subcontract with ORNL is to advance the fundamental understanding of thick thermal barrier coating systems. Previous reviews of thermal barrier coating technology concluded that the current level of understanding of coating system behavior is inadequate and the lack of fundamental understanding may impede the application of TTBC's to diesel engines. Areas of TTBC technology being examined in this program include powder characteristics and chemistry; bond coat composition; coating design, microstructure, and thickness as they affect properties, durability, and reliability; and TTBC 'aging' effects (microstructural and property changes) under diesel engine operating conditions. Methods to evaluate the reliability and durability of TTBC's have been developed that attempt to understand the fundamental strength of TTBC's for particular stress states.

Biopharmaceutical evaluation of time-controlled press-coated tablets containing polymers to adjust drug release.

PubMed

Halsas, M; Ervasti, P; Veski, P; Jürjenson, H; Marvola, M

1998-01-01

This paper deals with press-coated modified release tablets in which the drug dose is situated in the core or is divided between the core and the coat. The coat contains polymer (sodium alginate or hydroxypropylmethyl cellulose, HPMC) to control drug release. The main objective was to investigate how the pharmacokinetic profile of the model drug could be modified by altering the proportion of the drug between the core and the coat. The effect of the amount of the polymer in the coat was also studied. Bioavailability tests were carried out on healthy volunteers. In the absorption curves of the tablets containing 50%, 67% and 80% of the drug in the core and 180 mg HPMC in the coat a bimodal profile was observed. No bimodal release pattern in the in vitro dissolution studies was found. If the whole dose was incorporated in the core the absorption curve has only one clear t(max) value at about 10 h. Doubling the amount of HPMC in the coat dramatically decreased drug absorption. It was concluded that, if a slightly reduced t(max)-value was required, the viscosity grade of HPMC used should be lowered.

Thermal barrier coating life prediction model

NASA Technical Reports Server (NTRS)

Hillery, R. V.; Pilsner, B. H.; Cook, T. S.; Kim, K. S.

1986-01-01

This is the second annual report of the first 3-year phase of a 2-phase, 5-year program. The objectives of the first phase are to determine the predominant modes of degradation of a plasma sprayed thermal barrier coating system and to develop and verify life prediction models accounting for these degradation modes. The primary TBC system consists of an air plasma sprayed ZrO-Y2O3 top coat, a low pressure plasma sprayed NiCrAlY bond coat, and a Rene' 80 substrate. Task I was to evaluate TBC failure mechanisms. Both bond coat oxidation and bond coat creep have been identified as contributors to TBC failure. Key property determinations have also been made for the bond coat and the top coat, including tensile strength, Poisson's ratio, dynamic modulus, and coefficient of thermal expansion. Task II is to develop TBC life prediction models for the predominant failure modes. These models will be developed based on the results of thermmechanical experiments and finite element analysis. The thermomechanical experiments have been defined and testing initiated. Finite element models have also been developed to handle TBCs and are being utilized to evaluate different TBC failure regimes.

Environmental Barrier Coating (EBC) Durability Modeling; An Overview and Preliminary Analysis

NASA Technical Reports Server (NTRS)

Abdul-Aziz, A.; Bhatt, R. T.; Grady, J. E.; Zhu, D.

2012-01-01

A study outlining a fracture mechanics based model that is being developed to investigate crack growth and spallation of environmental barrier coating (EBC) under thermal cycling conditions is presented. A description of the current plan and a model to estimate thermal residual stresses in the coating and preliminary fracture mechanics concepts for studying crack growth in the coating are also discussed. A road map for modeling life and durability of the EBC and the results of FEA model(s) developed for predicting thermal residual stresses and the cracking behavior of the coating are generated and described. Further initial assessment and preliminary results showed that developing a comprehensive EBC life prediction model incorporating EBC cracking, degradation and spalling mechanism under stress and temperature gradients typically seen in turbine components is difficult. This is basically due to mismatch in thermal expansion difference between sub-layers of EBC as well as between EBC and substrate, diffusion of moisture and oxygen though the coating, and densification of the coating during operating conditions as well as due to foreign object damage, the EBC can also crack and spall from the substrate causing oxidation and recession and reducing the design life of the EBC coated substrate.

Visualization of Buried Marte Vallis Channels

NASA Image and Video Library

2013-03-07

This illustration schematically shows where the Shallow Radar instrument on NASA Mars Reconnaissance Orbiter detected flood channels that had been buried by lava flows in the Elysium Planitia region of Mars.

Subminiature eddy current transducers for studying boride coatings

NASA Astrophysics Data System (ADS)

Dmitriev, S. F.; Ishkov, A. V.; Malikov, V. N.; Sagalakov, A. M.

2016-07-01

Strengthening of parts and units of machines, increased reliability and longer service life is an important task of modern mechanical engineering. The main objects of study in the work were selected steel 65G and 50HGA, wear-resistant boride coatings ternary system Fe-B-Fe n B which were investigated by scanning electron microscopy and eddy-current nondestructive methods.

Electrochemical corrosion studies

NASA Technical Reports Server (NTRS)

Knockemus, W. W.

1986-01-01

The objective was to gain familiarity with the Model 350 Corrosion Measurement Console, to determine if metal protection by grease coatings can be measured by the polarization-resistance method, and to compare corrosion rates of 4130 steel coated with various greases. Results show that grease protection of steel may be determined electrochemically. Studies were also conducted to determine the effectiveness of certain corrosion inhibitors on aluminum and steel.

RADIOACTIVE OBJECT AND METHOD OF MAKING SAME

DOEpatents

Dorfman, L.M.; Shipko, F.J.

1959-09-01

A process is described for depositing an adherent coating of tritiated cuprene upon a solid body at the bottom of a vessel by introductng an atmosphere into the vessel containing a large fraction of tritiated acetylene whereby tritiated cuprene forms by polymerizing action and is deposited on the body by the action of gravity. An adherent, evenly distributed coating is obtained.

Corrosion Prevention for Wheeled Vehicle Systems

DTIC Science & Technology

1993-08-13

The audit objective was to evaluate the effectiveness and efficiency of the Army’s procedures for acquiring corrosion prevention and chemical agent...resistant coatings for wheeled vehicle systems. To accomplish this objective, we reviewed corrosion controls and painting processes. The audit also...included a review of the adequacy of internal controls related to the audit objective.

Modified carbon fibers to improve composite properties. [sizing fibers for reduced electrical conductivity and adhesion during combustion

NASA Technical Reports Server (NTRS)

Shepler, R. E.

1979-01-01

Thin coatings, 5 to 10 wt. percent, were applied to PAN-based carbon fibers. These coatings were intended to make the carbon fibers less electrically conductive or to cause fibers to stick together when a carbon fiber/epoxy composite burned. The effectiveness of the coatings in these regards was evaluated in burn tests with a test rig designed to simulate burning, impact and wind conditions which might release carbon fibers. The effect of the coatings on fiber and composite properties and handling was also investigated. Attempts at sizing carbon fibers with silicon dioxide, silicon carbide and boron nitride meet with varying degrees of success; however, none of these materials provided an electrically nonconductive coating. Coatings intended to stick carbon fibers together after a composite burned were sodium silicate, silica gel, ethyl silicate, boric acid and ammonium borate. Of these, only the sodium silicate and silica gel provided any sticking together of fibers. The amount of sticking was insufficient to achieve the desired objectives.

Phytochemical Characteristics of Coffee Bean Treated by Coating of Ginseng Extract

PubMed Central

Choi, Sang Yoon; Hong, Hee-Do; Bae, Hye-Min; Choi, Changsun; Kim, Kyung-Tack

2011-01-01

The principal objective of this study was to assess the instrumental and sensory characteristics of ginseng coffee with different ratios of the ingredients: type of coffee bean (Colombia, Brazil, and Indonesia), type of ginseng extract (white ginseng, red ginseng, and America ginseng) and concentration of ginseng extract (3, 6, and 9 w/v %). The sensory optimal condition of white ginseng coffee, red ginseng coffee and America ginseng coffee were as follows: 3% Indonesian coffee bean coated with 3% white ginseng extract, Colombian coffee bean coated with 6% red ginseng extract and Colombian coffee bean coated with 3% American ginseng extract, respectively. In particular, the Colombian coffee bean coated with 6% red ginseng extract had significantly higher scores than other samples in terms of flavor, taste, and overall preference. Additionally, the contents of total ginsenoside and total sugar and total phenolic compounds were also highest in the Colombian coffee bean coated with 6% red ginseng extract. PMID:23717089

Touch Temperature Coating for Off-the-Shelf Electrical Equipment Used on Spacecraft

NASA Technical Reports Server (NTRS)

Ungar, Eugene K.; Brady, Timothy K.

2010-01-01

Off-the-shelf electrical equipment is frequently used in space-based applications to control costs. However, the reduced heat transfer in the spacecraft microgravity environment causes the equipment to operate at significantly higher temperatures than it would in terrestrial applications. This creates touch temperature issues where items particularly metallic ones become too hot for the crew to handle safely. A touch temperature coating layup has been developed that can be added to spacebased electrically powered hardware. The coating allows the crew to safely handle the hardware, but only slightly impedes the heat transfer from the component during normal operation. In the present work, the coating generic requirements are developed and a layup is described that meets these specifications. Analytical and experimental results are presented that demonstrate the ability of the coating layup to increase the allowable limits of touch temperature while only marginally degrading heat transfer to the environment. This allows the spacecraft crew to handle objects that, if not coated, would be hot enough to cause pain or skin damage.

Control of exposure to hexavalent chromium concentration in shielded metal arc welding fumes by nano-coating of electrodes.

PubMed

Sivapirakasam, S P; Mohan, Sreejith; Santhosh Kumar, M C; Thomas Paul, Ashley; Surianarayanan, M

2017-04-01

Background Cr(VI) is a suspected human carcinogen formed as a by-product of stainless steel welding. Nano-alumina and nano-titania coating of electrodes reduced the welding fume levels. Objective To investigate the effect of nano-coating of welding electrodes on Cr(VI) formation rate (Cr(VI) FR) from a shielded metal arc welding process. Methods The core welding wires were coated with nano-alumina and nano-titania using the sol-gel dip coating technique. Bead-on plate welds were deposited on SS 316 LN plates kept inside a fume test chamber. Cr(VI) analysis was done using an atomic absorption spectrometer (AAS). Results A reduction of 40% and 76%, respectively, in the Cr(VI) FR was observed from nano-alumina and nano-titania coated electrodes. Increase in the fume level decreased the Cr(VI) FR. Discussion Increase in fume levels blocked the UV radiation responsible for the formation of ozone thereby preventing the formation of Cr(VI).

Osteoconductive hydroxyapatite coated PEEK for spinal fusion surgery

NASA Astrophysics Data System (ADS)

Hahn, Byung-Dong; Park, Dong-Soo; Choi, Jong-Jin; Ryu, Jungho; Yoon, Woon-Ha; Choi, Joon-Hwan; Kim, Jong-Woo; Ahn, Cheol-Woo; Kim, Hyoun-Ee; Yoon, Byung-Ho; Jung, In-Kwon

2013-10-01

Polyetheretherketone (PEEK) has attracted much interest as biomaterial for interbody fusion cages due to its similar stiffness to bone and good radio-transparency for post-op visualization. Hydroxyapatite (HA) coating stimulates bone growth to the medical implant. The objective of this work is to make an implant consisting of biocompatible PEEK with an osteoconductive HA surface for spinal or orthopedic applications. Highly dense and well-adhered HA coating was developed on medical-grade PEEK using aerosol deposition (AD) without thermal degradation of the PEEK. The HA coating had a dense microstructure with no cracks or pores, and showed good adhesion to PEEK at adhesion strengths above 14.3 MPa. The crystallinity of the HA coating was remarkably enhanced by hydrothermal annealing as post-deposition heat-treatment. In addition, in vitro and in vivo biocompatibility of PEEK, in terms of cell adhesion morphology, cell proliferation, differentiation, and bone-to-implant contact ratio, were remarkably enhanced by the HA coating through AD.

Development of strain tolerant thermal barrier coating systems, tasks 1 - 3

NASA Technical Reports Server (NTRS)

Anderson, N. P.; Sheffler, K. D.

1983-01-01

Insulating ceramic thermal barrier coatings can reduce gas turbine airfoil metal temperatures as much as 170 C (about 300 F), providing fuel efficiency improvements greater than one percent and durability improvements of 2 to 3X. The objective was to increase the spalling resistance of zirconia based ceramic turbine coatings. To accomplish this, two baseline and 30 candidate duplex (layered MCrAlY/zirconia based ceramic) coatings were iteratively evaluated microstructurally and in four series of laboratory burner rig tests. This led to the selection of two candidate optimized 0.25 mm (0.010 inch) thick plasma sprayed partially stabilized zirconia ceramics containing six weight percent yttria and applied with two different sets of process parameters over a 0.13 mm (0.005 inch) thick low pressure chamber sprayed MCrAlY bond coat. Both of these coatings demonstrated at least 3X laboratory cyclic spalling life improvement over the baseline systems, as well as cyclic oxidation life equivalent to 15,000 commercial engine flight hours.

Saliva and tongue coating pH before and after use of mouthwashes and relationship with parameters of halitosis

PubMed Central

TOLENTINO, Elen de Souza; CHINELLATO, Luiz Eduardo Montenegro; TARZIA, Olinda

2011-01-01

Objectives The aim of this work was to evaluate saliva and tongue coating pH in oral healthy patients with morning bad breath before and after use of different oral mouthrinses. Material and Methods aliva and tongue coating pH of 50 patients allocated in 5 groups were measured respectively by a digital pHmeter and color pH indicators, before, immediately after and 30 min after rinsing 5 different mouthrinses: cetilpiridine chloride associated with sodium chloride, triclosan, enzymatic solution, essential oil and distilled water. Results Only triclosan and essential oil increased salivary pH immediately after rising. The enzymatic solution decreased salivary and tongue coating pH immediately after rinsing. Conclusion Salivary pH tended to be acidic while tongue coating pH tended to be alkaline, even after rising. Triclosan and essential oil mouthrinses increased salivary pH immediately after rinsing. Enzymatic solution decreased saliva and tongue coating pH immediately after rising. PMID:21552707

Investigation of an Electromagnetic Induction Sensor

DTIC Science & Technology

2011-12-01

c) (f) Figure 5. Respose plotted on an Argand diagram over the center of a) TS-50 anti-personnel landmines buried 0 to...5 cm deep, b) MAI-75 anti- personnel landmines buried 0 to 5 cm deep, and c) patio stones buried 2.5 to 11 cm deep. Magnitude of the respose at the 21...Figure 6. Respose plotted on an Argand diagram over the center of empty grid locations. II - 377 a) b) c) d) Figure 5. Response of four mines

Monolithic integration of a GaAlAs buried-heterostructure laser and a bipolar phototransistor

NASA Technical Reports Server (NTRS)

Bar-Chaim, N.; Harder, CH.; Margalit, S.; Yariv, A.; Katz, J.; Ury, I.

1982-01-01

A GaAlAs buried-heterostructure laser has been monolithically integrated with a bipolar phototransistor. The heterojunction transistor was formed by the regrowth of the burying layers of the laser. Typical threshold current values for the lasers were 30 mA. Common-emitter current gains for the phototransistor of 100-400 and light responsitivity of 75 A/W (for wavelengths of 0.82 micron) at collector current levels of 15 mA were obtained.

Corrective action investigation plan: Cactus Spring Waste Trenches. Revision 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This Correction Action Investigation Plan (CAIP) contains environmental sample collection objectives and logic for the Corrective Action Unit No. 426, which includes the Cactus Spring Waste Trenches, located at the Tonopah Test Range. The purpose of this investigation is to generate sufficient data to establish the types of waste buried in the trenches, identify the presence and nature of contamination, determine the vertical extent of contaminant migration below the Cactus Spring Waste Trenches, and determine the appropriate course of action for the site. The potential courses of action for the site are clean closure, closure in place (with or withoutmore » remediation), or no further action. The scope of this investigation will include drilling and collecting subsurface samples from within and below the trenches. Sampling locations will be biased toward the areas most likely to be contaminated. The Cactus Spring Waste Trenches Site is identified as one of three potential locations for buried, radioactively contaminated materials from the Double Tracks Test. This test was the first of four storage-transportation tests conducted in 1963 as part of Operation Roller Coaster. The experiment involved the use of live animals to assess the inhalation intake of a plutonium aerosol.« less

Spectral analysis of ground penetrating radar signals in concrete, metallic and plastic targets

NASA Astrophysics Data System (ADS)

Santos, Vinicius Rafael N. dos; Al-Nuaimy, Waleed; Porsani, Jorge Luís; Hirata, Nina S. Tomita; Alzubi, Hamzah S.

2014-01-01

The accuracy of detecting buried targets using ground penetrating radar (GPR) depends mainly on features that are extracted from the data. The objective of this study is to test three spectral features and evaluate the quality to provide a good discrimination among three types of materials (concrete, metallic and plastic) using the 200 MHz GPR system. The spectral features which were selected to check the interaction of the electromagnetic wave with the type of material are: the power spectral density (PSD), short-time Fourier transform (STFT) and the Wigner-Ville distribution (WVD). The analyses were performed with simulated data varying the sizes of the targets and the electrical properties (relative dielectric permittivity and electrical conductivity) of the soil. To check if the simulated data are in accordance with the real data, the same approach was applied on the data obtained in the IAG/USP test site. A noticeable difference was found in the amplitude of the studies' features in the frequency domain and these results show the strength of the signal processing to try to differentiate buried materials using GPR, and so can be used in urban planning and geotechnical studies.

Geoarchaeological results from geophysical prospections at the Roman city of Urbs Salvia, central Italy

NASA Astrophysics Data System (ADS)

Schettino, Antonio; Perna, Roberto; Pierantoni, Pietro Paolo; Ghezzi, Annalisa; Tassi, Luca; Cingolani, Sofia

2017-04-01

We report on a combined magnetic-GPR survey performed in 2015 and 2016 at the ancient Roman city of Urbs Salvia, located in central Italy. The main objective of this survey was to reconstruct the urban organization of the city forum and determine possible sites of future excavations. We found a complex pattern of buried structures, possibly resulting from the coexistence of republican and imperial artifacts and burned structures. A test excavation at the location where we detected a long linear structure characterized by strong magnetic signal revealed the presence of thermal baths. GPR data were acquired in areas characterized by high magnetic noise induced by metallic infrastructures (e.g., fences), which prevented a correct acquisition of archaeological anomalies. These data not only allowed to overcome the magnetic noise, but provided interesting 3D reconstructions of the buried structures. A detailed GPR survey in the theatre area was also performed, with the aim to investigate the plan of the porticus post scaenam. This survey allowed to identify some interesting structures related to different chronological phases and confirms the epigraphic data related to the development of the monument.

Buried Mesozoic rift basins of Moroccan Atlantic continental margin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohamed, N.; Jabour, H.; El Mostaine, M.

1995-08-01

The Atlantic continental margin is the largest frontier area for oil and gas exploration in Morocco. Most of the activity has been concentrated where Upper Jurassic carbonate rocks have been the drilling objectives, with only one significant but non commercial oil discovery. Recent exploration activities have focused on early Mesozoic Rift basins buried beneath the post-rift sediments of the Middle Atlantic coastal plain. Many of these basins are of interest because they contain fine-grained lacustrine rocks that have sufficient organic richness to be classified as efficient oil prone source rock. Location of inferred rift basins beneath the Atlantic coastal plainmore » were determined by analysis of drilled-hole data in combination with gravity anomaly and aeromagnetic maps. These rift basins are characterized by several half graben filled by synrift sediments of Triassic age probably deposited in lacustrine environment. Coeval rift basins are known to be present in the U.S. Atlantic continental margin. Basin modeling suggested that many of the less deeply bored rift basins beneath the coastal plain are still within the oil window and present the most attractive exploration targets in the area.« less

Late Quaternary environments of the Waco Mammoth site, Texas USA

NASA Astrophysics Data System (ADS)

Nordt, Lee; Bongino, John; Forman, Steven; Esker, Don; Benedict, Anita

2015-11-01

The Waco Mammoth Site (WMS) in central Texas contains the remains of the largest mammoth herd (Mammuthus columbi) in North America that died in a single catastrophic event. Most mammoths at the site died on a gravel bar of the ancient Bosque River adjacent to a collapsing tributary wall. However, the timing and cause of death of the 26 mammoths documented to date are controversial. The objectives of this research are to: describe and interpret the alluvial stratigraphy and infer the cause of death, employ optically stimulated luminescence (OSL) dating to determine the timing of death, and analyze stable C isotopes of pedogenic carbonate to infer local plant communities, dietary habits, and summer temperatures. Dating of quartz from seven sediment samples by OSL places the death event to a weighted mean of 66.8 ± 5.0 ka. The site is coeval with Marine Oxygen Isotope Stage 4, consistent with our reconstructed mean July temperatures 4°C cooler than today based on a buried soil isotopic transfer function. Our buried soil isotopic interpretation of a dominance of C3 plants is contrary to previous studies of mammoth tooth enamel at the site suggesting a dietary preference for warm season grasses (C4).

Objective research on tongue manifestation of patients with eczema.

PubMed

Yu, Zhifeng; Zhang, Haifang; Fu, Linjie; Lu, Xiaozuo

2017-07-20

Tongue observation often depends on subjective judgment, it is necessary to establish an objective and quantifiable standard for tongue observation. To discuss the features of tongue manifestation of patients who suffered from eczema with different types and to reveal the clinical significance of the tongue images. Two hundred patients with eczema were recruited and divided into three groups according to the diagnostic criteria. Acute group had 47 patients, subacute group had 82 patients, and chronic group had 71 patients. The computerized tongue image digital analysis device was used to detect tongue parameters. The L*a*b* color model was applied to classify tongue parameters quantitatively. For parameters such as tongue color, tongue shape, color of tongue coating, and thickness or thinness of tongue coating, there was a significant difference among acute group, subacute group and chronic group (P< 0.05). For Lab values of both tongue and tongue coating, there was statistical significance among the above types of eczema (P< 0.05). Tongue images can reflect some features of eczema, and different types of eczema may be related to the changes of tongue images. The computerized tongue image digital analysis device can reflect the tongue characteristics of patients with eczema objectively.

A method of evolving novel feature extraction algorithms for detecting buried objects in FLIR imagery using genetic programming

NASA Astrophysics Data System (ADS)

Paino, A.; Keller, J.; Popescu, M.; Stone, K.

2014-06-01

In this paper we present an approach that uses Genetic Programming (GP) to evolve novel feature extraction algorithms for greyscale images. Our motivation is to create an automated method of building new feature extraction algorithms for images that are competitive with commonly used human-engineered features, such as Local Binary Pattern (LBP) and Histogram of Oriented Gradients (HOG). The evolved feature extraction algorithms are functions defined over the image space, and each produces a real-valued feature vector of variable length. Each evolved feature extractor breaks up the given image into a set of cells centered on every pixel, performs evolved operations on each cell, and then combines the results of those operations for every cell using an evolved operator. Using this method, the algorithm is flexible enough to reproduce both LBP and HOG features. The dataset we use to train and test our approach consists of a large number of pre-segmented image "chips" taken from a Forward Looking Infrared Imagery (FLIR) camera mounted on the hood of a moving vehicle. The goal is to classify each image chip as either containing or not containing a buried object. To this end, we define the fitness of a candidate solution as the cross-fold validation accuracy of the features generated by said candidate solution when used in conjunction with a Support Vector Machine (SVM) classifier. In order to validate our approach, we compare the classification accuracy of an SVM trained using our evolved features with the accuracy of an SVM trained using mainstream feature extraction algorithms, including LBP and HOG.

Performance of buried pipe installation.

DOT National Transportation Integrated Search

2010-05-01

The purpose of this study is to determine the effects of geometric and mechanical parameters : characterizing the soil structure interaction developed in a buried pipe installation located under : roads/highways. The drainage pipes or culverts instal...

Attenuation characteristics of the fundamental modes that propagate in buried iron water pipes.

PubMed

Long, R; Lowe, M; Cawley, P

2003-09-01

The attenuation of the fundamental non-torsional modes that propagate down buried iron water pipes has been studied. The mode shapes, mode attenuation due to leakage into the surrounding medium and the scattering of the modes as they interact with pipe joints and fittings have been investigated. In the low frequency region the mode predicted to dominate over significant propagation distances approximates a plane wave in the water within the pipe. The established acoustic technique used to locate leaks in buried iron water pipes assumes that leak noise propagates as a single non-dispersive mode at a velocity related to the low frequency asymptote of this water borne mode. Experiments have been conducted on buried water mains at test sites in the UK to verify the attenuation and velocity dispersion predictions.

Buried penis: An unrecognized risk factor in the development of invasive penile cancer.

PubMed

Abdulla, Alym; Daya, Dean; Pinthus, Jehonathan; Davies, Timothy

2012-10-01

One of the documented benefits of neonatal circumcision is protection against invasive penile cancer. To date there have been a handful of published cases of invasive penile cancer in men circumcised as neonates. We report a case of a 73-year-old man, with a history of neonatal circumcision with no evidence of previous human papillomavirus exposure, who developed a buried penis secondary to obesity. He was diagnosed with Grade 2, pT3N0 squamous cell carcinoma of the penis. This report suggests that buried penis may pose a risk factor for the development of penile cancer despite the protective effects of neonatal circumcision. Thus periodic examination of a buried penis is warranted even in patients with no risk factors for penile cancer. A review of the literature is provided.

A novel self-aligned oxygen (SALOX) implanted SOI MOSFET device structure

NASA Astrophysics Data System (ADS)

Tzeng, J. C.; Baerg, W.; Ting, C.; Siu, B.

The morphology of the novel self-aligned oxygen implanted SOI (SALOX SOI) [1] MOSFET was studied. The channel silicon of SALOX SOI was confirmed to be undamaged single crystal silicon and was connected with the substrate. Buried oxide formed by oxygen implantation in this SALOX SOI structure was shown by a cross section transmission electron micrograph (X-TEM) to be amorphous. The source/drain silicon on top of the buried oxide was single crystal, as shown by the transmission electron diffraction (TED) pattern. The source/drain regions were elevated due to the buried oxide volume expansion. A sharp silicon—silicon dioxide interface between the source/drain silicon and buried oxide was observed by Auger electron spectroscopy (AES). Well behaved n-MOS transistor current voltage characteristics were obtained and showed no I-V kink.

Decomposition patterns of buried remains at different intervals in the Central Highveld region of South Africa.

PubMed

Marais-Werner, A; Myburgh, J; Meyer, A; Nienaber, W C; Steyn, M

2017-07-01

Burial of remains is an important factor when one attempts to establish the post-mortem interval as it reduces, and in extreme cases, excludes oviposition by Diptera species. This in turn leads to modification of the decomposition process. The aim of this study was to record decomposition patterns of buried remains using a pig model. The pattern of decomposition was evaluated at different intervals and recorded according to existing guidelines. In order to contribute to our knowledge on decomposition in different settings, a quantifiable approach was followed. Results indicated that early stages of decomposition occurred rapidly for buried remains within 7-33 days. Between 14 and 33 days, buried pigs displayed common features associated with the early to middle stages of decomposition, such as discoloration and bloating. From 33 to 90 days advanced decomposition manifested on the remains, and pigs then reached a stage of advanced decomposition where little change was observed in the next ±90-183 days after interment. Throughout this study, total body scores remained higher for surface remains. Overall, buried pigs followed a similar pattern of decomposition to those of surface remains, although at a much slower rate when compared with similar post-mortem intervals in surface remains. In this study, the decomposition patterns and rates of buried remains were mostly influenced by limited insect activity and adipocere formation which reduces the rate of decay in a conducive environment (i.e. burial in soil).

Properties of Galvanized and Galvannealed Advanced High Strength Hot Rolled Steels

DOE Office of Scientific and Technical Information (OSTI.GOV)

V.Y. Guertsman; E. Essadiqi; S. Dionne

2008-04-01

The objectives of the project were (i) to develop the coating process information to achieve good quality coatings on 3 advanced high strength hot rolled steels while retaining target mechanical properties, (ii) to obtain precise knowledge of the behavior of these steels in the various forming operations and (iii) to establish accurate user property data in the coated conditions. Three steel substrates (HSLA, DP, TRIP) with compositions providing yield strengths in the range of 400-620 MPa were selected. Only HSLA steel was found to be suitable for galnaizing and galvannealing in the hot rolled condition.

CRADA with United Solar Technologies and Pacific Northwest Laboratory (PNL-021): Thin film materialsfor low-cost high performance solar concentrators

NASA Astrophysics Data System (ADS)

Martin, P. M.; Affinito, J. D.; Gross, M. E.; Bennett, W. D.

1995-03-01

The objectives of this project were to develop and evaluate promising low-cost dielectric and polymer-protected thin-film reflective metal coatings to be applied to preformed continuously-curved solar reflector panels to enhance their solar reflectance, and to demonstrate protected solar reflective coatings on preformed solar concentrator panels. The opportunity for this project arose from a search by United Solar Technologies (UST) for organizations and facilities capable of applying reflective coatings to large preformed panels. PNL was identified as being uniquely qualified to participate in this collaborative project.

Adiabatic Wankel type rotary engine

NASA Technical Reports Server (NTRS)

Kamo, R.; Badgley, P.; Doup, D.

1988-01-01

This SBIR Phase program accomplished the objective of advancing the technology of the Wankel type rotary engine for aircraft applications through the use of adiabatic engine technology. Based on the results of this program, technology is in place to provide a rotor and side and intermediate housings with thermal barrier coatings. A detailed cycle analysis of the NASA 1007R Direct Injection Stratified Charge (DISC) rotary engine was performed which concluded that applying thermal barrier coatings to the rotor should be successful and that it was unlikely that the rotor housing could be successfully run with thermal barrier coatings as the thermal stresses were extensive.

Gnathostoma infection in Nakhon Nayok and Prachin Buri, Central Thailand.

PubMed

Rojekittikhun, Wichit; Chaiyasith, Tossapon; Nuamtanong, Supaporn; Pubampen, Somchit; Maipanich, Wanna; Tungtrongchitr, Rungsunn

2002-09-01

Gnathostoma infection in Nakhon Nayok and Prachin Buri Provinces, Central Thailand, was investigated. The prevalence and intensity of infection of swamp eels were determined; dog fecal samples and fresh-water copepods were examined for evidence of infection. The overall prevalence of eel infection was 38.1% (117/307) in Nakhon Nayok and 24.0% (74/308) in Prachin Buri--the former rate being significantly higher than the latter. Most of the positive Nalkhon Nayok eels (53.8%) harbored only 1-9 larvae; only one eel bore more than 50 larvae. In Prachin Buri, 67.6% of the positive eels harbored 1-9 larvae; again, only one eel bore more than 50 larvae. The mean number of 11.0 +/- 10.4 larvae/eel in Nakhon Nayok was not significantly different from that of Prachin Buri (9.3 +/- 11.4). A total of 1,292 gnathostome larvae were recovered from 307 eels in Nakhon Nayok. Of these, 52.3% had accumulated in the liver and 47.7% had spread throughout the muscles. In eels from Prachin Buri, 50.6% and 49.4% of the total of 688 larvae (from 308 eels) were found in the liver and muscles, respectively. The larvae preferred encysting in ventral of muscles rather than dorsal part; they preferred the middle portion to the anterior and posterior portions. The average length of gnathostome larvae recovered from Nakhon Nayok eels was 4.0 +/- 0.5 mm (range 2.5-5.1 mm) and the average body width was 0.40 +/- 0.05 mm (range 0.29-0.51 mm). Those from eels in Prachin Buri were 3.9 +/- 0.5 mm (range 2.2-5.1 mm) and 0.34 +/- 0.05 mm (range 0.20-0.48 mm), respectively. The mean body length and width of the larvae from eels in Nakhon Nayok were significantly greater than those of the larvae from eels in Prachin Buri. In Ban Phrao, Nakhon Nayok, none of the first 44 fecal specimens examined was positive. Of the second (68) and the third (70) specimens, one (1.5%) and two (2.9%) samples were positive. However, six months after the third fecal collection, no eggs were found. In Tha Ngam, Prachin Buri, no eggs were found in all three batches (109, 115, and 100 fecal samples). A cyclops survey of 4,000-5,000 crustacea from each of two areas (Ban Phrao and Tha Ngam) found no evidence of natural cyclops infection.

Noradrenergic facilitation of shock-probe defensive burying in lateral septum of rats, and modulation by chronic treatment with desipramine.

PubMed

Bondi, Corina O; Barrera, Gabriel; Lapiz, M Danet S; Bedard, Tania; Mahan, Amy; Morilak, David A

2007-03-30

We have previously shown that acute stress-induced release of norepinephrine (NE) facilitates anxiety-like behavioral responses to stress, such as reduction in open-arm exploration on the elevated-plus maze and in social behavior on the social interaction test. Since these responses represent inhibition of ongoing behavior, it is important to also address whether NE facilitates a response that represents an activation of behavior. Correspondingly, it is unknown how a chronic elevation in tonic steady-state noradrenergic (NA) neurotransmission induced by NE reuptake blockade might alter this acute modulatory function, a regulatory process that may be pertinent to the anxiolytic effects of NE reuptake blockers such as desipramine (DMI). Therefore, in this study, we investigated noradrenergic modulation of the shock-probe defensive burying response in the lateral septum (LS). In experiment 1, shock-probe exposure induced an acute 3-fold increase in NE levels measured in LS of male Sprague-Dawley rats by microdialysis. Shock-probe exposure also induced a modest rise in plasma ACTH, taken as an indicator of perceived stress, that returned to baseline more rapidly in rats that were allowed to bury the probe compared to rats prevented from burying by providing them with minimal bedding, indicating that the active defensive burying behavior is an effective coping strategy that reduces the impact of acute shock probe-induced stress. In experiment 2, blockade of either alpha(1)- or beta-adrenergic receptors in LS by local antagonist microinjection immediately before testing reduced defensive burying and increased immobility. In the next experiment, chronic DMI treatment increased basal extracellular NE levels in LS, and attenuated the acute shock probe-induced increase in NE release in LS relative to baseline. Chronic DMI treatment decreased shock-probe defensive burying behavior in a time-dependent manner, apparent only after 2 weeks or more of drug treatment. Moreover, rats treated chronically with DMI showed no significant rise of plasma ACTH in response to shock-probe exposure. Thus, acute stress-induced release of NE in LS facilitated defensive burying, an active, adaptive behavioral coping response. Chronic treatment with the NE reuptake blocker and antidepressant drug DMI attenuated acute noradrenergic facilitation of the active burying response, and also attenuated the level of perceived stress driving that response. These results suggest that long-term regulation of the acute modulatory function of NE by chronic treatment with reuptake blockers may contribute to the mechanisms by which such drugs exert their anxiolytic effects in the treatment of stress-related psychiatric conditions, including depression and anxiety.

METHOD OF FORMING TANTALUM SILICIDE ON TANTALUM SURFACES

DOEpatents

Bowman, M.G.; Krikorian, N.H.

1961-10-01

A method is described for forming a non-corrosive silicide coating on tantalum. The coating is made through the heating of trirhenium silicides in contact with the tantalum object to approximately 1400 deg C at which temperature trirhenium silicide decomposes into rhenium and gaseous silicons. The silicon vapor reacts with the tantalum surface to form a tantalum silicide layer approximately 10 microns thick. (AEC)

A Novel Method for Remote Depth Estimation of Buried Radioactive Contamination.

PubMed

Ukaegbu, Ikechukwu Kevin; Gamage, Kelum A A

2018-02-08

Existing remote radioactive contamination depth estimation methods for buried radioactive wastes are either limited to less than 2 cm or are based on empirical models that require foreknowledge of the maximum penetrable depth of the contamination. These severely limits their usefulness in some real life subsurface contamination scenarios. Therefore, this work presents a novel remote depth estimation method that is based on an approximate three-dimensional linear attenuation model that exploits the benefits of using multiple measurements obtained from the surface of the material in which the contamination is buried using a radiation detector. Simulation results showed that the proposed method is able to detect the depth of caesium-137 and cobalt-60 contamination buried up to 40 cm in both sand and concrete. Furthermore, results from experiments show that the method is able to detect the depth of caesium-137 contamination buried up to 12 cm in sand. The lower maximum depth recorded in the experiment is due to limitations in the detector and the low activity of the caesium-137 source used. Nevertheless, both results demonstrate the superior capability of the proposed method compared to existing methods.

Investigating buried polymer interfaces using sum frequency generation vibrational spectroscopy

PubMed Central

Chen, Zhan

2010-01-01

This paper reviews recent progress in the studies of buried polymer interfaces using sum frequency generation (SFG) vibrational spectroscopy. Both buried solid/liquid and solid/solid interfaces involving polymeric materials are discussed. SFG studies of polymer/water interfaces show that different polymers exhibit varied surface restructuring behavior in water, indicating the importance of probing polymer/water interfaces in situ. SFG has also been applied to the investigation of interfaces between polymers and other liquids. It has been found that molecular interactions at such polymer/liquid interfaces dictate interfacial polymer structures. The molecular structures of silane molecules, which are widely used as adhesion promoters, have been investigated using SFG at buried polymer/silane and polymer/polymer interfaces, providing molecular-level understanding of polymer adhesion promotion. The molecular structures of polymer/solid interfaces have been examined using SFG with several different experimental geometries. These results have provided molecular-level information about polymer friction, adhesion, interfacial chemical reactions, interfacial electronic properties, and the structure of layer-by-layer deposited polymers. Such research has demonstrated that SFG is a powerful tool to probe buried interfaces involving polymeric materials, which are difficult to study by conventional surface sensitive analytical techniques. PMID:21113334

A Novel Method for Remote Depth Estimation of Buried Radioactive Contamination

PubMed Central

2018-01-01

Existing remote radioactive contamination depth estimation methods for buried radioactive wastes are either limited to less than 2 cm or are based on empirical models that require foreknowledge of the maximum penetrable depth of the contamination. These severely limits their usefulness in some real life subsurface contamination scenarios. Therefore, this work presents a novel remote depth estimation method that is based on an approximate three-dimensional linear attenuation model that exploits the benefits of using multiple measurements obtained from the surface of the material in which the contamination is buried using a radiation detector. Simulation results showed that the proposed method is able to detect the depth of caesium-137 and cobalt-60 contamination buried up to 40 cm in both sand and concrete. Furthermore, results from experiments show that the method is able to detect the depth of caesium-137 contamination buried up to 12 cm in sand. The lower maximum depth recorded in the experiment is due to limitations in the detector and the low activity of the caesium-137 source used. Nevertheless, both results demonstrate the superior capability of the proposed method compared to existing methods. PMID:29419759

Clinical and post mortem analysis of combat neck injury used to inform a novel coverage of armour tool.

PubMed

Breeze, J; Fryer, R; Hare, J; Delaney, R; Hunt, N C; Lewis, E A; Clasper, J C

2015-04-01

There is a requirement in the Ministry of Defence for an objective method of comparing the area of coverage of different body armour designs for future applications. Existing comparisons derived from surface wound mapping are limited in that they can only demonstrate the skin entry wound location. The Coverage of Armour Tool (COAT) is a novel three-dimensional model capable of comparing the coverage provided by body armour designs, but limited information exists as to which anatomical structures require inclusion. The aim of this study was to assess the utility of COAT, in the assessment of neck protection, using clinically relevant injury data. Hospital notes and post mortem records of all UK soldiers injured by an explosive fragment to the neck between 01 Jan 2006 and 31 December 2012 from Iraq and Afghanistan were analysed to determine which anatomical structures were responsible for death or functional disability at one year post injury. Using COAT a comparison of three ballistic neck collar designs was undertaken with reference to the percentage of these anatomical structures left exposed. 13/81 (16%) survivors demonstrated complications at one year, most commonly upper limb weakness from brachial plexus injury or a weak voice from laryngeal trauma. In 14/94 (15%) soldiers the neck wound was believed to have been the sole cause of death, primarily from carotid artery damage, spinal cord transection or rupture of the larynx. COAT objectively demonstrated that despite the larger OSPREY collar having almost double the surface area than the two-piece prototype collar, the percentage area of vulnerable cervical structures left exposed only reduced from 16.3% to 14.4%. COAT demonstrated its ability to objectively quantify the potential effectiveness of different body armour designs in providing coverage of vulnerable anatomical structures from different shot line orientations. To improve its utility, it is recommended that COAT be further developed to enable weapon and tissue specific information to be modelled, and that clinically significant injuries to other body regions are also incorporated. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Performance evaluation of buried pipe installation.

DOT National Transportation Integrated Search

2010-05-01

The purpose of this study is to determine the effects of geometric and mechanical parameters characterizing the soil structure interaction developed in a buried pipe installation located under roads/highways. The drainage pipes or culverts installed ...

Performance of buried pipe installation : tech summary.

DOT National Transportation Integrated Search

2010-05-01

Existing codes and recommendations often require standard/minimum values for the bedding, backfi ll, and fi ll cover geometric and : mechanical properties in the installation of buried pipes under transportation facilities. These recommended values a...

Effects of compaction and soil moisture on American burying beetles.

DOT National Transportation Integrated Search

2016-12-25

Silphid beetles in the genus Nicrophorus bury themselves during periods of inactivity, however, the influence of soil characteristics on burial behavior remains unclear. We examined soil preferences of the federally endangered Nicrophorus americanus,...

75 FR 38042 - Specifications and Drawings for Construction of Direct Buried Plant

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-01

... CFR Part 1755 Specifications and Drawings for Construction of Direct Buried Plant AGENCY: Rural... Plant (Form 515a). This document corrects the Docket ID number. FOR FURTHER INFORMATION CONTACT: Joyce...

Regional Studies of Highland-Lowland Age Differences Across the Mars Crustal Dichotomy Boundary

NASA Technical Reports Server (NTRS)

Frey, H. V.; DeSoto, G. E.; Lazrus, R. M.

2005-01-01

Regional differences in crater retention ages (CRAs) across the Mars dichotomy boundary are compared to the global highland-lowland age difference previously determined from visible and buried impact basins based on MOLA-derived Quasi-Circular Depressions (QCDs). Here Western Arabia (WA) is compared with Ismenius Lacus (IL). We find the buried lowlands in the two regions have total CRAs essentially identical to the global average. Even more intriguing, the WA cratered terrain appears to have a CRA like that of the adjacent buried lowlands,

SP2 Deployment at Boston College—Aerodyne-Led Coated Black Carbon Study (BC4) Final Campaign Summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onasch, T. B.; Sedlacek, A. J.

The main objective of the Boston College-Aerodyne led laboratory study (BC4) was to measure the optical properties of black carbon (BC) particles from a diffusion flame directly and after being coated with secondary organic and inorganic material and to achieve optical closure with model predictions. The measurements of single particle BC mass and population mixing states provided by a single particle soot photometer (SP2) was central to achieving the laboratory-based study’s objective. Specifically, the DOE ARM SP2 instrument participated in the BC4 project to address the following scientific questions: 1. What is the mass-specific absorption coefficient as a function ofmore » secondary organic and inorganic material coatings? 2. What is the spread in the population mixing states within our carefully generated laboratory particles? 3. How does the SP2 instrument respond to well-characterized, internally mixed BC-containing particles?« less

Modelling the effect of buried valleys on groundwater flow: case study in Ventspils vicinity, Latvia

NASA Astrophysics Data System (ADS)

Delina, Aija; Popovs, Konrads; Bikse, Janis; Retike, Inga; Babre, Alise; Kalvane, Gunta

2015-04-01

Buried subglacial valleys are widely distributed in glaciated regions and they can have great influence on groundwater flow and hence on groundwater resources. The aim of this study is to evaluate the effect of the buried valleys on groundwater flow in a confined aquifer (Middle Devonian Eifelian stage Arukila aquifer, D2ar) applying numerical modelling. The study area is located at vicinity of Ventspils Town, near wellfield Ogsils where number of the buried valleys with different depth and filling material are present. Area is located close to the Baltic Sea at Piejūra lowland Rinda plain and regional groundwater flow is towards sea. Territory is covered by thin layer of Quaternary sediments in thicknesses of 10 to 20 meters although Prequaternary sediments are exposed at some places. Buried valleys are characterized as narrow, elongated and deep formations that is be filled with various, mainly Pleistocene glacigene sediments - either till loam of different ages or sand and gravel or interbedding of both above mentioned. The filling material of the valleys influences groundwater flow in the confined aquifers which is intercepted by the valleys. It is supposed that glacial till loam filled valleys serves as a barrier to groundwater flow and as a recharge conduit when filled with sand and gravel deposits. Numerical model was built within MOSYS modelling system (Virbulis et al. 2012) using finite element method in order to investigate buried valley influence on groundwater flow in the study area. Several conceptual models were tested in numerical model depending on buried valley filling material: sand and gravel, till loam or mixture of them. Groundwater flow paths and travel times were studied. Results suggested that valley filled with glacial till is acting as barrier and it causes sharp drop of piezometric head and downward flow. Valley filled with sand and gravel have almost no effect on piezometric head distribution, however it this case buried valleys encourage groundwater recharge from shallower aquifers. Modelling results with and without valleys shows that buried valleys affect piezometric head in narrow zone around valley. Sand and gravel filled buried valleys recharges confined aquifer with relatively "new" water, thus creating high vulnerability zones in the study area. This research is supported by European Regional Development Fund project Nr.2013/0054/2DP/2.1.1.1.0/13/APIA/VIAA/007 and NRP project EVIDENnT project "Groundwater and climate scenarios" subproject "Groundwater Research". References: Virbulis, J., Timuhins, A., Klints, I., Seņņikovs, J., Bethers, U., Popovs, K. 2012. Script based MOSYS system for the generation of a three dimensional geological structure and the calculation of groundwater flow: case study of the Baltic Artesian Basin. In: Highlights of groundwater research in the Baltic Artesian Basin. University of Latvia, Riga, pp. 53-74.

Three-Dimensional Electromagnetic Scattering from Layered Media with Rough Interfaces for Subsurface Radar Remote Sensing

NASA Astrophysics Data System (ADS)

Duan, Xueyang

The objective of this dissertation is to develop forward scattering models for active microwave remote sensing of natural features represented by layered media with rough interfaces. In particular, soil profiles are considered, for which a model of electromagnetic scattering from multilayer rough surfaces with or without buried random media is constructed. Starting from a single rough surface, radar scattering is modeled using the stabilized extended boundary condition method (SEBCM). This method solves the long-standing instability issue of the classical EBCM, and gives three-dimensional full wave solutions over large ranges of surface roughnesses with higher computational efficiency than pure numerical solutions, e.g., method of moments (MoM). Based on this single surface solution, multilayer rough surface scattering is modeled using the scattering matrix approach and the model is used for a comprehensive sensitivity analysis of the total ground scattering as a function of layer separation, subsurface statistics, and sublayer dielectric properties. The buried inhomogeneities such as rocks and vegetation roots are considered for the first time in the forward scattering model. Radar scattering from buried random media is modeled by the aggregate transition matrix using either the recursive transition matrix approach for spherical or short-length cylindrical scatterers, or the generalized iterative extended boundary condition method we developed for long cylinders or root-like cylindrical clusters. These approaches take the field interactions among scatterers into account with high computational efficiency. The aggregate transition matrix is transformed to a scattering matrix for the full solution to the layered-medium problem. This step is based on the near-to-far field transformation of the numerical plane wave expansion of the spherical harmonics and the multipole expansion of plane waves. This transformation consolidates volume scattering from the buried random medium with the scattering from layered structure in general. Combined with scattering from multilayer rough surfaces, scattering contributions from subsurfaces and vegetation roots can be then simulated. Solutions of both the rough surface scattering and random media scattering are validated numerically, experimentally, or both. The experimental validations have been carried out using a laboratory-based transmit-receive system for scattering from random media and a new bistatic tower-mounted radar system for field-based surface scattering measurements.

Studies of contemporary glacier basal ice cryostructures to identify buried basal ice in the permafrost: an example from the Matanuska Glacier, Alaska.

NASA Astrophysics Data System (ADS)

Stephani, E.; Fortier, D.; Kanevskiy, M.; Dillon, M.; Shur, Y.

2007-12-01

In the permafrost, massive ice bodies occur as buried glacier ice, aufeis ice, recrystalized snow, massive segregated ice, injection ice, ice wedges or ice formed in underground cavities ("pool ice", "thermokarst-cave ice"). The origin of massive ice bodies in the permafrost bears considerable implications for the reconstructions of paleoenvironments and paleoclimates. Our work aims to help the permafrost scientists working on massive icy sediments to distinguish buried basal glacier ice from other types of buried ice. To do so, the properties and structure of contemporary basal ice must be well known. Field investigations at the Matanuska Glacier (Chugach range, South-central Alaska), consisted in descriptions and sampling of natural basal ice exposures. We have used the basal ice facies classification of Lawson (1979) which is simple, easy to use in the field and provides a good framework for the description of basal ice exposures. Cores were extracted and brought back to the laboratory for water and grain-size analyses. The sediments forming the cryostructure were mostly polymodal, poorly sorted gravelly silt to gravelly fine sand, with mud contents generally over 50%. These data will be used to calibrate three-dimensional (3D) models produced from micro-tomographic scans of basal ice which will produce quantitative estimates of volumetric ice and sediments contents of basal ice cryostructures. Ultimately, visual qualitative and quantitative characterization of the basal ice components of 3D models together with field observations and laboratory analysis will allow for a new micro-facies and cryostructures classification of the basal ice. Our work will also have applications in glaciology, glacial geology, geomorphology, Quaternary and paleo-climatological studies based on inferences made from the structure of basal glacier ice. This paper presents the internal composition of the basal ice facies in terms of cryostructures assemblages (Fortier et al.: 2007) and sedimentological properties. Fortier, D., Kanevskiy, M, Stephani, E., Dillon, M., Shur, Y. 2007. Facies and cryostructures of glacier basal ice as an object of permafrost study, an example from the Matanuska Glacier, Alaska. Canadian Quaternary Association Conference, Ottawa, June 2007: 75. Lawson, D.E. 1979. Sedimentological analysis of the western terminus region of the Matanuska Glacier, Alaska. Cold Regions Engineering and Research Laboratory, Hanover, N.H., Report 79-9.

Electrochemically induced actuation of liquid metal marbles

NASA Astrophysics Data System (ADS)

Tang, Shi-Yang; Sivan, Vijay; Khoshmanesh, Khashayar; O'Mullane, Anthony P.; Tang, Xinke; Gol, Berrak; Eshtiaghi, Nicky; Lieder, Felix; Petersen, Phred; Mitchell, Arnan; Kalantar-Zadeh, Kourosh

2013-06-01

Controlled actuation of soft objects with functional surfaces in aqueous environments presents opportunities for liquid phase electronics, novel assembled super-structures and unusual mechanical properties. We show the extraordinary electrochemically induced actuation of liquid metal droplets coated with nanoparticles, so-called ``liquid metal marbles''. We demonstrate that nanoparticle coatings of these marbles offer an extra dimension for affecting the bipolar electrochemically induced actuation. The nanoparticles can readily migrate along the surface of liquid metals, upon the application of electric fields, altering the capacitive behaviour and surface tension in a highly asymmetric fashion. Surprising actuation behaviours are observed illustrating that nanoparticle coatings can have a strong effect on the movement of these marbles. This significant novel phenomenon, combined with unique properties of liquid metal marbles, represents an exciting platform for enabling diverse applications that cannot be achieved using rigid metal beads.Controlled actuation of soft objects with functional surfaces in aqueous environments presents opportunities for liquid phase electronics, novel assembled super-structures and unusual mechanical properties. We show the extraordinary electrochemically induced actuation of liquid metal droplets coated with nanoparticles, so-called ``liquid metal marbles''. We demonstrate that nanoparticle coatings of these marbles offer an extra dimension for affecting the bipolar electrochemically induced actuation. The nanoparticles can readily migrate along the surface of liquid metals, upon the application of electric fields, altering the capacitive behaviour and surface tension in a highly asymmetric fashion. Surprising actuation behaviours are observed illustrating that nanoparticle coatings can have a strong effect on the movement of these marbles. This significant novel phenomenon, combined with unique properties of liquid metal marbles, represents an exciting platform for enabling diverse applications that cannot be achieved using rigid metal beads. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00185g

QCM-D on mica for parallel QCM-D-AFM studies.

PubMed

Richter, Ralf P; Brisson, Alain

2004-05-25

Quartz crystal microbalance with dissipation monitoring (QCM-D) has developed into a recognized method to study adsorption processes in liquid, such as the formation of supported lipid bilayers and protein adsorption. However, the large intrinsic roughness of currently used gold-coated or silica-coated QCM-D sensors limits parallel structural characterization by atomic force microscopy (AFM). We present a method for coating QCM-D sensors with thin mica sheets operating in liquid with high stability and sensitivity. We define criteria to objectively assess the reliability of the QCM-D measurements and demonstrate that the mica-coated sensors can be used to follow the formation of supported lipid membranes and subsequent protein adsorption. This method allows combining QCM-D and AFM investigations on identical supports, providing detailed physicochemical and structural characterization of model membranes.

Performance of buried pipe installation : technical summary.

DOT National Transportation Integrated Search

2010-05-01

The goal of this research project was to determine the effects of geometric and mechanical parameters characterizing the soil-structure interaction developed in a buried pipe installation. Parameters such as pipe ring stiff ness, bedding thickness, t...

Carbon limitation patterns in buried and open urban streams

EPA Science Inventory

Urban streams alternate between darkened buried segments dominated by heterotrophic processes and lighted open segments dominated by autotrophic processes. We hypothesized that labile carbon leaking from autotrophic cells would reduce heterotrophic carbon limitation in open chan...

Atomic friction at exposed and buried graphite step edges: Experiments and simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Zhijiang; Martini, Ashlie, E-mail: amartini@ucmerced.edu

2015-06-08

The surfaces of layered materials such as graphite exhibit step edges that affect friction. Step edges can be exposed, where the step occurs at the outmost layer, or buried, where the step is underneath another layer of material. Here, we study friction at exposed and buried step edges on graphite using an atomic force microscope (AFM) and complementary molecular dynamics simulations of the AFM tip apex. Exposed and buried steps exhibit distinct friction behavior, and the friction on either step is affected by the direction of sliding, i.e., moving up or down the step, and the bluntness of the tip.more » These trends are analyzing in terms of the trajectory of the AFM tip as it moves over the step, which is a convolution of the topography of the surface and the tip shape.« less

South Polar Hills

NASA Technical Reports Server (NTRS)

2006-01-01

28 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a summer scene from the south polar region of Mars. The circular feature in the northeast (upper right) corner of the image is an old meteor impact crater that has been partially filled and buried. The cone-shaped hill that occurs within the crater on its east (right) side is a remnant of material that once covered and completely buried the crater. Perhaps beneath the surfaces in the rest of the image there are other craters that have been filled and buried such that we cannot know, from an image, that they ever existed. The theme of filled, buried, and exhumed craters is one that repeats itself -- over and over again -- all over Mars.

Location near: 80.3oS, 286.1oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

Field investigation on structural performance of the buried UPVC pipes with and without geogrid reinforcement

NASA Astrophysics Data System (ADS)

Teja, Akkineni Surya; Rajkumar, R.; Gokula Krishnan, B.; Aravindh, R.

2018-02-01

Buried pipes are used mainly for water supply and drainage besides many other applications such as oil, liquefied natural gas, coal slurries and mine tailings. The pipes used may be rigid (reinforced concrete, vitrified clay and ductile iron) or flexible (Steel, UPVC, aluminium, Fiber glass and High-density polyethylene) although the distinction between them is blurring. Flexible pipe design is governed by deflection or buckling. UPVC pipes are preferred due to light weight, long term chemical stability and cost efficiency. This project aims to study the load deformation behaviour of the buried pipe and stress variation across the cross section of the pipe under static loading along with the influence of depth of embedment, density of backfill on the deformation and stresses in pipe and the deformation behaviour of buried pipe when soil is reinforced with geogrid reinforcement and evaluate the structural performance of the pipe.

Backscattered electron simulations to evaluate sensitivity against electron dosage of buried semiconductor features

NASA Astrophysics Data System (ADS)

Mukhtar, Maseeh; Thiel, Bradley

2018-03-01

In fabrication, overlay measurements of semiconductor device patterns have conventionally been performed using optical methods. Beginning with image-based techniques using box-in-box to the more recent diffraction-based overlay (DBO). Alternatively, use of SEM overlay is under consideration for in-device overlay. Two main application spaces are measurement features from multiple mask levels on the same surface and buried features. Modern CD-SEMs are adept at measuring overlay for cases where all features are on the surface. In order to measure overlay of buried features, HV-SEM is needed. Gate-to-fin and BEOL overlay are important use cases for this technique. A JMONSEL simulation exercise was performed for these two cases using 10 nm line/space gratings of graduated increase in depth of burial. Backscattered energy loss results of these simulations were used to calculate the sensitivity measurements of buried features versus electron dosage for an array of electron beam voltages.

Microflora distributions in paleosols: a method for calculating the validity of radiocarbon-dated surfaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahaney, W.C.; Boyer, M.G.

1986-08-01

Microflora (bacteria and fungi) distributions in several paleosols from Mount Kenya, East Africa, provide important information about contamination of buried soil horizons dated by radiocarbon. High counts of bacteria and fungi in buried soils provide evidence for contamination by plant root effects or ground water movement. Profiles with decreasing counts versus depth appear to produce internally consistent and accurate radiocarbon dates. Profiles with disjunct or bimodal distributions of microflora at various depths produce internally inconsistent chronological sequences of radiocarbon-dated buried surfaces. Preliminary results suggest that numbers up to 5 x 10/sup 2/ g/sup -1/ for bacteria in buried A horizonsmore » do not appear to affect the validity of /sup 14/C dates. Beyond this threshold value, contamination appears to produce younger dates, the difference between true age and /sup 14/C age increasing with the amount of microflora contamination.« less

Flow accelerated organic coating degradation

NASA Astrophysics Data System (ADS)

Zhou, Qixin

Applying organic coatings is a common and the most cost effective way to protect metallic objects and structures from corrosion. Water entry into coating-metal interface is usually the main cause for the deterioration of organic coatings, which leads to coating delamination and underfilm corrosion. Recently, flowing fluids over sample surface have received attention due to their capability to accelerate material degradation. A plethora of works has focused on the flow induced metal corrosion, while few studies have investigated the flow accelerated organic coating degradation. Flowing fluids above coating surface affect corrosion by enhancing the water transport and abrading the surface due to fluid shear. Hence, it is of great importance to understand the influence of flowing fluids on the degradation of corrosion protective organic coatings. In this study, a pigmented marine coating and several clear coatings were exposed to the laminar flow and stationary immersion. The laminar flow was pressure driven and confined in a flow channel. A 3.5 wt% sodium chloride solution and pure water was employed as the working fluid with a variety of flow rates. The corrosion protective properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. Equivalent circuit models were employed to interpret the EIS spectra. The time evolution of coating resistance and capacitance obtained from the model was studied to demonstrate the coating degradation. Thickness, gloss, and other topography characterizations were conducted to facilitate the assessment of the corrosion. The working fluids were characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The influence of flow rate, fluid shear, fluid composition, and other effects in the coating degradation were investigated. We conclude that flowing fluid on the coating surface accelerates the transport of water, oxygen, and ions into the coating, as well as promotes the migration of coating materials from the coating into the working fluid, where coatings experience more severe deterioration in their barrier property under flowing conditions. Pure water has shown to be a much more aggressive working fluid than electrolyte solutions. The flowing fluid over the coating surface could be used as an effective acceleration method.

Biological influence of Ca/P ratio on calcium phosphate coatings by sol-gel processing.

PubMed

Catauro, M; Papale, F; Sapio, L; Naviglio, S

2016-08-01

The objective of this work has been to develop low temperature sol-gel glass coatings to modify the substrate surface and to evaluate their bioactivity and biocompatibility. Glasses, based on SiO2·CaO·P2O5, were synthesized by the sol-gel technique using tetraethyl orthosilicate, calcium nitrate tetrahydrate and triethyl phosphate as precursors of SiO2, CaO and P2O5, respectively. Those materials, still in the sol phase, have been used to coat substrates by means of the dip-coating technique. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) has been used for characterize coatings and a microstructural analysis has been obtained using scanning electron microscopy (SEM). The potential applications of the coatings in the biomedical field were evaluated by bioactivity and biocompatibility tests. The coated substrate was immersed in simulated body fluid (SBF) for 21days and the hydroxyapatite deposition on its surface was subsequently evaluated via SEM-EDXS analysis, as an index of bone-bonding capability. In order to study the cell behavior and response to our silica based materials, prepared via the sol-gel method, with various Ca/P ratio and coating substrate, we have used the human osteoblast-like U2OS cell line. Copyright © 2016 Elsevier B.V. All rights reserved.