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Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
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1

Mechanical Behavior I  

Science Conference Proceedings (OSTI)

Mar 5, 2013... (IMC) is essential for understandingthe mechanical behavior of the ... Reliability and by the SHaRE User Facility, Scientific User Facilities...

2

Mechanical Behavior of Materials Committee  

Science Conference Proceedings (OSTI)

The Mechanical Behavior of Materials Committee is part of the Structural Materials Division. Our Mission: Covers relationships between microstructure and

3

Defect behavior of polycrystalline solar cell silicon  

DOE Green Energy (OSTI)

The major objective of this study, conducted from October 1988 to September 1991, was to gain an understanding of the behavior of impurities in polycrystalline silicon and the influence of these impurities on solar cell efficiency. The authors studied edge-defined film-fed growth (EFG) and cast poly-Si materials and solar cells. With EFG Si they concentrated on chromium-doped materials and cells to determine the role of Cr on solar cell performance. Cast poly-Si samples were not deliberately contaminated. Samples were characterized by cell efficiency, current-voltage, deep-level transient spectroscopy (DLTS), surface photovoltage (SPV), open-circuit voltage decay, secondary ion mass spectrometry, and Fourier transform infrared spectroscopy measurements. They find that Cr forms Cr-B pairs with boron at room temperature and these pairs dissociate into Cr{sub i}{sup +} and B{sup {minus}} during anneals at 210{degrees}C for 10 min. Following the anneal, Cr-B pairs reform at room temperature with a time constant of 230 h. Chromium forms CrSi{sub 2} precipitates in heavily contaminated regions and they find evidence of CrSi{sub 2} gettering, but a lack of chromium segregation or precipitation to grain boundaries and dislocations. Cr-B pairs have well defined DLTS peaks. However, DLTS spectra of other defects are not well defined, giving broad peaks indicative of defects with a range of energy levels in the band gap. In some high-stress, low-efficiency cast poly-Si they detect SiC precipitates, but not in low-stress, high-efficiency samples. SPV measurements result in nonlinear SPV curves in some materials that are likely due to varying optical absorption coefficients due to locally varying stress in the material.

Schroder, D.K.; Park, S.H.; Hwang, I.G.; Mohr, J.B.; Hanly, M.P. [Arizona State Univ., Tempe, AZ (US). Center for Solid State Electronics Research

1993-05-01T23:59:59.000Z

4

Understanding Defect Behavior in Nuclear Energy Materials  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2012. Symposium, International Symposium on Defects, Transport and Related Phenomena.

5

Mechanical Behavior - Programmaster.org  

Science Conference Proceedings (OSTI)

Oct 20, 2011 ... Ceramic Matrix Composites: Mechanical Behavior ... such as leading edges and combustor liners, are subjected to simultaneous thermal and...

6

Mechanical Behavior, Failure Mode  

Science Conference Proceedings (OSTI)

Feb 15, 2010 ... The largest bending strains are measured when cooling down from the ... to Bi- 11Ag, while the Zn-40Sn samples show no passive behavior.

7

Mechanical Behavior II  

Science Conference Proceedings (OSTI)

Mar 5, 2013 ... Impact of Cooling Rate on Low Silver Sn-Ag-Cu Solder Interconnect Board Level Mechanical Shock and Thermal Cycling Performance:...

8

Mechanical Behavior of Indium Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanical Behavior of Indium Nanostructures Print Mechanical Behavior of Indium Nanostructures Print Indium is a key material in lead-free solder applications for microelectronics due to its excellent wetting properties, extended ductility, and high electrical conductivity. With the size of electronic devices continuing to shrink and the promise of indium-based nanotechnologies, it is important to develop a fundamental understanding of this material's small-scale mechanical properties and reliability. Researchers from the University of Waterloo, California Institute of Technology, and Los Alamos National Laboratory have collaborated with a team at ALS Beamline 12.3.2 to investigate the small-scale mechanics of indium nanostructures. Scanning x-ray microdiffraction (μSXRD) studies revealed that the indium microstructure is typical of a well-annealed metal, containing very few initial dislocations and showing close-to-theoretical strength.

9

Mechanical Behavior of Indium Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanical Behavior of Indium Nanostructures Print Mechanical Behavior of Indium Nanostructures Print Indium is a key material in lead-free solder applications for microelectronics due to its excellent wetting properties, extended ductility, and high electrical conductivity. With the size of electronic devices continuing to shrink and the promise of indium-based nanotechnologies, it is important to develop a fundamental understanding of this material's small-scale mechanical properties and reliability. Researchers from the University of Waterloo, California Institute of Technology, and Los Alamos National Laboratory have collaborated with a team at ALS Beamline 12.3.2 to investigate the small-scale mechanics of indium nanostructures. Scanning x-ray microdiffraction (μSXRD) studies revealed that the indium microstructure is typical of a well-annealed metal, containing very few initial dislocations and showing close-to-theoretical strength.

10

Mechanical Behavior of Indium Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanical Behavior of Indium Nanostructures Print Mechanical Behavior of Indium Nanostructures Print Indium is a key material in lead-free solder applications for microelectronics due to its excellent wetting properties, extended ductility, and high electrical conductivity. With the size of electronic devices continuing to shrink and the promise of indium-based nanotechnologies, it is important to develop a fundamental understanding of this material's small-scale mechanical properties and reliability. Researchers from the University of Waterloo, California Institute of Technology, and Los Alamos National Laboratory have collaborated with a team at ALS Beamline 12.3.2 to investigate the small-scale mechanics of indium nanostructures. Scanning x-ray microdiffraction (μSXRD) studies revealed that the indium microstructure is typical of a well-annealed metal, containing very few initial dislocations and showing close-to-theoretical strength.

11

Mechanical Behavior of Tempered Martensitic Steels for ...  

Science Conference Proceedings (OSTI)

Presentation Title, Mechanical Behavior of Tempered Martensitic Steels for Ultrasupercritical Steam Applications. Author(s), Jeffrey A. Hawk, Paul D. Jablonski,...

12

Mechanical Behavior of Bulk Nanocrystalline Copper Alloys ...  

Science Conference Proceedings (OSTI)

Presentation Title, Mechanical Behavior of Bulk Nanocrystalline Copper Alloys Produced by High Energy Ball Milling. Author(s), Hamed Bahmanpour, Khaled M.

13

Aluminum Matrix Composites Mechanical Behavior  

Science Conference Proceedings (OSTI)

Oct 28, 2009... and fracture behavior for each condition of homogeneity via compression tests and chevron-notch short rod specimens, respectively.

14

Mechanical Behavior at Nanoscale I  

Science Conference Proceedings (OSTI)

Jul 31, 2011 ... -Deformation mechanisms of nano structures including nanocrystalline, nano- twinned, nanowires, nano-laminates, and nano-pillars.

15

Defect-related internal dissipation in mechanical resonators and the study of coupled mechanical systems.  

Science Conference Proceedings (OSTI)

Understanding internal dissipation in resonant mechanical systems at the micro- and nanoscale is of great technological and fundamental interest. Resonant mechanical systems are central to many sensor technologies, and microscale resonators form the basis of a variety of scanning probe microscopies. Furthermore, coupled resonant mechanical systems are of great utility for the study of complex dynamics in systems ranging from biology to electronics to photonics. In this work, we report the detailed experimental study of internal dissipation in micro- and nanomechanical oscillators fabricated from amorphous and crystalline diamond materials, atomistic modeling of dissipation in amorphous, defect-free, and defect-containing crystalline silicon, and experimental work on the properties of one-dimensional and two-dimensional coupled mechanical oscillator arrays. We have identified that internal dissipation in most micro- and nanoscale oscillators is limited by defect relaxation processes, with large differences in the nature of the defects as the local order of the material ranges from amorphous to crystalline. Atomistic simulations also showed a dominant role of defect relaxation processes in controlling internal dissipation. Our studies of one-dimensional and two-dimensional coupled oscillator arrays revealed that it is possible to create mechanical systems that should be ideal for the study of non-linear dynamics and localization.

Friedmann, Thomas Aquinas; Czaplewski, David A.; Sullivan, John Patrick; Modine, Normand Arthur; Wendt, Joel Robert; Aslam, Dean (Michigan State University, Lansing, MI); Sepulveda-Alancastro, Nelson (University of Puerto Rico, Mayaguez, PR)

2007-01-01T23:59:59.000Z

16

Mechanical Behavior of Low Dimensional Materials  

Science Conference Proceedings (OSTI)

Frederic Sansoz, The University of Vermont Christoph Eberl, University of Karlsruhe. Scope, The nanomechanical behavior of low dimensional materials (

17

Probing the Structural, Electrical and Mechanical Behaviors of Nano ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Examples for probing the structural, electrical and mechanical behaviors of nano-materials by various advanced TEM techniques are introduced...

18

Mechanical Behavior of Biological Materials II  

Science Conference Proceedings (OSTI)

Feb 16, 2010 ... Bone has high fracture resistance because of its capability to .... and that these mechanisms are most active within the inner enamel. .... higher proliferation, and well spreading morphology in relation to pure chitosan scaffold.

19

Mechanical behavior of dip-brazed aluminum sandwich panels  

E-Print Network (OSTI)

An experimental study was carried out to determine the mechanical behavior of sandwich panels containing cellular cores of varying shape. Compression and four point bend tests were performed on sandwich panels with square ...

Hohmann, Brian P. (Brian Patrick)

2007-01-01T23:59:59.000Z

20

Nanostructure stabilization and mechanical behavior of binary nanocrystalline alloys  

E-Print Network (OSTI)

The unique mechanical behavior of nanocrystalline metals has become of great interest in recent years, owing to both their remarkable strength and the emergence of new deformation physics at the nanoscale. Of particular ...

Trelewicz, Jason R

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Model for Electron-Beam-Induced Current Analysis of mc-Si Addressing Defect Contrast Behavior in Heavily Contaminated PV Material: Preprint  

DOE Green Energy (OSTI)

Much work has been done to correlate electron-beam-induced current (EBIC) contrast behavior of extended defects with the character and degree of impurity decoration. However, existing models fail to account for recently observed contrast behavior of defects in heavily contaminated mc-Si PV cells. We have observed large increases in defect contrast with decreasing temperature for all electrically active defects, regardless of their initial contrast signatures at ambient temperature. This negates the usefulness of the existing models in identifying defect character and levels of impurity decoration based on the temperature dependence of the contrast behavior. By considering the interactions of transition metal impurities with the silicon lattice and extended defects, we attempt to provide an explanation for these observations. Our findings will enhance the ability of the PV community to understand and mitigate the effects of these types of defects as the adoption of increasingly lower purity feedstocks for mc-Si PV production continues.

Guthrey, H.; Gorman, B.; Al-Jassim, M.

2012-06-01T23:59:59.000Z

22

2010 Thin Film & Small Scale Mechanical Behavior Gordon Research Conference  

SciTech Connect

Over the past decades, it has been well established that the mechanical behavior of materials changes when they are confined geometrically at least in one dimension to small scale. It is the aim of the 2010 Gordon Conference on 'Thin Film and Small Scale Mechanical Behavior' to discuss cutting-edge research on elastic, plastic and time-dependent deformation as well as degradation mechanisms like fracture, fatigue and wear at small scales. As in the past, the conference will benefit from contributions from fundamental studies of physical mechanisms linked to material science and engineering reaching towards application in modern applications ranging from optical and microelectronic devices and nano- or micro-electrical mechanical systems to devices for energy production and storage. The conference will feature entirely new testing methodologies and in situ measurements as well as recent progress in atomistic and micromechanical modeling. Particularly, emerging topics in the area of energy conversion and storage, such as material for batteries will be highlighted. The study of small-scale mechanical phenomena in systems related to energy production, conversion or storage offer an enticing opportunity to materials scientists, who can provide new insight and investigate these phenomena with methods that have not previously been exploited.

Dr. Thomas Balk

2010-07-30T23:59:59.000Z

23

Mechanism for recombination of radiation-induced point defects at interphase boundaries  

E-Print Network (OSTI)

Interfaces play a critical role in the extraordinary resistance to irradiation damage in nanostructured materials. Atomistic simulations are performed to examine defect production and recovery at incoherent interphase ...

Demkowicz, Michael J.

24

Melt Related Defects in Alloy 706 and Their Effects on Mechanical ...  

Science Conference Proceedings (OSTI)

Remelting (ESR) or Vacuum Arc Remelting (VAR) or both. The remelting process (ESR or VAR) can introduce segregation type of defects in the material.

25

Impact of defects on the electrical transport, optical properties and failure mechanisms of GaN nanowires.  

SciTech Connect

We present the results of a three year LDRD project that focused on understanding the impact of defects on the electrical, optical and thermal properties of GaN-based nanowires (NWs). We describe the development and application of a host of experimental techniques to quantify and understand the physics of defects and thermal transport in GaN NWs. We also present the development of analytical models and computational studies of thermal conductivity in GaN NWs. Finally, we present an atomistic model for GaN NW electrical breakdown supported with experimental evidence. GaN-based nanowires are attractive for applications requiring compact, high-current density devices such as ultraviolet laser arrays. Understanding GaN nanowire failure at high-current density is crucial to developing nanowire (NW) devices. Nanowire device failure is likely more complex than thin film due to the prominence of surface effects and enhanced interaction among point defects. Understanding the impact of surfaces and point defects on nanowire thermal and electrical transport is the first step toward rational control and mitigation of device failure mechanisms. However, investigating defects in GaN NWs is extremely challenging because conventional defect spectroscopy techniques are unsuitable for wide-bandgap nanostructures. To understand NW breakdown, the influence of pre-existing and emergent defects during high current stress on NW properties will be investigated. Acute sensitivity of NW thermal conductivity to point-defect density is expected due to the lack of threading dislocation (TD) gettering sites, and enhanced phonon-surface scattering further inhibits thermal transport. Excess defect creation during Joule heating could further degrade thermal conductivity, producing a viscous cycle culminating in catastrophic breakdown. To investigate these issues, a unique combination of electron microscopy, scanning luminescence and photoconductivity implemented at the nanoscale will be used in concert with sophisticated molecular-dynamics calculations of surface and defect-mediated NW thermal transport. This proposal seeks to elucidate long standing material science questions for GaN while addressing issues critical to realizing reliable GaN NW devices.

Armstrong, Andrew M.; Aubry, Sylvie; Shaner, Eric Arthur; Siegal, Michael P.; Li, Qiming; Jones, Reese E.; Westover, Tyler; Wang, George T.; Zhou, Xiao Wang; Talin, Albert Alec; Bogart, Katherine Huderle Andersen; Harris, C. Thomas; Huang, Jian Yu

2010-09-01T23:59:59.000Z

26

Effects of Lamination on Mechanical Behavior of Nano-Structured ...  

Science Conference Proceedings (OSTI)

Aerosol Route Synthesis of Copper Oxide Nanoparticles Using Copper Nitrate Solution AlGaAs-Based Optical ... Defect Energetics and Fission Product Transport in ZrC ... Enhancing Mineral Beneficiation by High Intensity Power Ultrasound.

27

Mechanical Strength and Fracture Behavior of Silicon Wafer Based ...  

Science Conference Proceedings (OSTI)

A Study on the Stress Test of Truck Frames for Freight Trains A Study on the ... Defect Energetics and Fission Product Transport in ZrC Deformation Field and...

28

Thermal Behavior of Mechanically Milled Chalcogenide Glass Na2S ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2013. Symposium, ACerS Cooper Award Session. Presentation Title, Thermal Behavior of...

29

On the Changes in Mechanical Behavior of Fish Scales by Polar ...  

Science Conference Proceedings (OSTI)

Presentation Title, On the Changes in Mechanical Behavior of Fish Scales by Polar Solvents. Author(s), Guihua Li, Mobin Yahyazadehfar, Adriana MC Garrano

30

Determination of Electrochemical Performance and Thermo-Mechanical-Chemical Stability of SOFCs from Defect Modeling  

DOE Green Energy (OSTI)

This research was focused on two distinct but related issues. The first issue concerned using defect modeling to understand the relationship between point defect concentration and the electrochemical, thermo-chemical and mechano-chemical properties of typical solid oxide fuel cell (SOFC) materials. The second concerned developing relationships between the microstructural features of SOFC materials and their electrochemical performance. To understand the role point defects play in ceramics, a coherent analytical framework was used to develop expressions for the dependence of thermal expansion and elastic modulus on point defect concentration in ceramics. These models, collectively termed the continuum-level electrochemical model (CLEM), were validated through fits to experimental data from electrical conductivity, I-V characteristics, elastic modulus and thermo-chemical expansion experiments for (nominally pure) ceria, gadolinia-doped ceria (GDC) and yttria-stabilized zirconia (YSZ) with consistently good fits. The same values for the material constants were used in all of the fits, further validating our approach. As predicted by the continuum-level electrochemical model, the results reveal that the concentration of defects has a significant effect on the physical properties of ceramic materials and related devices. Specifically, for pure ceria and GDC, the elastic modulus decreased while the chemical expansion increased considerably in low partial pressures of oxygen. Conversely, the physical properties of YSZ remained insensitive to changes in oxygen partial pressure within the studied range. Again, the findings concurred exactly with the predictions of our analytical model. Indeed, further analysis of the results suggests that an increase in the point defect content weakens the attractive forces between atoms in fluorite-structured oxides. The reduction treatment effects on the flexural strength and the fracture toughness of pure ceria were also evaluated at room temperature. The results reveal that the flexural strength decreases significantly after heat treatment in very low oxygen partial pressure environments; however, in contrast, fracture toughness is increased by 30-40% when the oxygen partial pressure was decreased to 10{sup -20} to 10{sup -22} atm range. Fractographic studies show that microcracks developed at 800 oC upon hydrogen reduction are responsible for the decreased strength. To understand the role of microstructure on electrochemical performance, electrical impedance spectra from symmetric LSM/YSZ/LSM cells was de-convoluted to obtain the key electrochemical components of electrode performance, namely charge transfer resistance, surface diffusion of reactive species and bulk gas diffusion through the electrode pores. These properties were then related to microstructural features, such as triple-phase boundary length and tortuosity. From these experiments we found that the impedance due to oxygen adsorption obeys a power law with pore surface area, while the impedance due to charge transfer is found to obey a power-law with respect to triple phase boundary length. A model based on kinetic theory explaining the power-law relationships observed was then developed. Finally, during our EIS work on the symmetric LSM/YSZ/LSM cells a technique was developed to improve the quality of high-frequency impedance data and their subsequent de-convolution.

Eric Wachsman; Keith L. Duncan

2006-09-30T23:59:59.000Z

31

Mechanical behavior analysis of CDIO production-blood vessel robot in curved blood vessel  

Science Conference Proceedings (OSTI)

In order to analyze mechanical behavior of blood vessel robot (student's CDIO production) in curved blood, and provide the data for outline design of robot, the flow field out side of robot is numerical simulated. The results show that the vessel shape ... Keywords: blood vessel robot, curved blood vessel, mechanical behavior analysis, numerical simulation

Fan Jiang; Chunliang Zhang; Yijun Wang

2010-10-01T23:59:59.000Z

32

Mechanical Behavior of a Cellulose-Based Scaffold in Vascular ...  

Science Conference Proceedings (OSTI)

A Comparative Study of the Compressive Mechanical Properties of Young and ... of Ti-6Al-4V for Medical Applications after Surface Modification by Anodization.

33

Mechanical Behavior of Green Materials - Programmaster.org  

Science Conference Proceedings (OSTI)

Scope, An increasing number materials are identified as green for a variety of ... Thermo-mechanical response of materials in energy storage, distribution, and...

34

Grain boundary effects on defect production and mechanical properties of irradiated nanocrystalline SiC  

SciTech Connect

Grain boundaries (GBs) are known to play an important role in determining the mechanical and functional properties of nanocrystalline materials. In this study, we used molecular dynamics simulations to investigate the effects of damaged GBs on the mechanical properties of SiC that is irradiated by 10 keV Si atoms. The results reveal that irradiation promotes GB sliding and reduces the ability of GBs to block dislocations, which improves the deformation ability of nanocrystalline SiC. However, irradiation causes local rearrangements in disordered clusters and pinning of dislocations in the grain region, which restrains its deformation. These two mechanisms arise from the irradiation effects on GBs and grains, and these mechanisms compete in nanocrystalline SiC during irradiation. The irradiation effects on GBs dominate at low irradiation doses, and the effects on grains dominate at high doses; the result of these combined effects is a peak ductility of 0.09 dpa in nanocrystalline SiC.

Jin Enze; Niu Lisha; Lin Enqiang; Song Xiaoxiong [AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China)

2012-05-15T23:59:59.000Z

35

Mechanical Behavior of Biological Materials III - Programmaster.org  

Science Conference Proceedings (OSTI)

Mar 3, 2011... Carbon Nanotubes: Ankur Gupta1; Debrupa Lahiri2; Sanat Ghosh2; Garima Tripathi1; ... Microstructural and Mechanical Investigation of Macadamia ... by the methods of Instrumental Neutron Activation Analysis (INAA) and...

36

The mechanical behavior of heavily overconsolidated resedimented Boston Blue Clay  

E-Print Network (OSTI)

Geotechnical engineers encounter some of the most challenging problems in heavily overconsolidated soils. Clays under this condition originated in nature or man-made construction. This thesis investigates the mechanical ...

Vargas Bustamante, Albalyra Geraldine

2013-01-01T23:59:59.000Z

37

2012 THIN FILM AND SMALL SCALE MECHANICAL BEHAVIOR GRS/GRC, JULY 21-27, 2012  

SciTech Connect

The mechanical behavior of materials with small dimension(s) is of both fundamental scientific interest and technological relevance. The size effects and novel properties that arise from changes in deformation mechanism have important implications for modern technologies such as thin films for microelectronics and MEMS devices, thermal and tribological coatings, materials for energy production and advanced batteries, etc. The overarching goal of the 2012 Gordon Research Conference on "Thin Film and Small Scale Mechanical Behavior" is to discuss recent studies and future opportunities regarding elastic, plastic and time-dependent deformation, as well as degradation and failure mechanisms such as fatigue, fracture and wear. Specific topics of interest include, but are not limited to: fundamental studies of physical mechanisms governing small-scale mechanical behavior; advances in test techniques for materials at small length scales, such as nanotribology and high-temperature nanoindentation; in-situ mechanical testing and characterization; nanomechanics of battery materials, such as swelling-induced phenomena and chemomechanical behavior; flexible electronics; mechanical properties of graphene and carbon-based materials; mechanical behavior of small-scale biological structures and biomimetic materials. Both experimental and computational work will be included in the oral and poster presentations at this Conference.

Balk, Thomas

2012-07-27T23:59:59.000Z

38

Modeling the mechanical behavior of amorphous metals by shear transformation zone dynamics  

E-Print Network (OSTI)

A new mesoscale modeling technique for the thermo-mechanical behavior of amorphous metals is proposed. The modeling framework considers the shear transformation zone (STZ) as the fundamental unit of deformation, and ...

Homer, Eric Richards, 1980-

2010-01-01T23:59:59.000Z

39

Mechanical behavior of closed-cell and hollow-sphere metallic foams  

E-Print Network (OSTI)

(cont.) The elastic anisotropy and yield surfaces are fully characterized, and numerical equations are developed to allow the simple evaluation of the effect of geometric and material properties on the mechanical behavior ...

Sanders, Wynn Steven, 1974-

2002-01-01T23:59:59.000Z

40

Computational mechanical modeling of the behavior of carbon nanotubes  

Science Conference Proceedings (OSTI)

This paper presents a computational method for the mechanical simulation of carbon nanotubes, whose complexity is linear on the number of atoms. The regularity of a graphene lattice at its energy ground permits the definition of a tiling scheme that ... Keywords: carbon nanotubes, computational method, mathematical modeling, molecular dynamics, numerical simulation

Maria Morandi Cecchi; Alberto Giovanni Busetto

2007-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Processing and mechanical behavior of hypereutectoid steel wires  

DOE Green Energy (OSTI)

Hypereutectoid steels have the potential for dramatically increasing the strength of wire used in tire cord and in other high strength wire applications. The basis for this possible breakthrough is the elimination of a brittle proeutectoid network that can form along grain boundaries if appropriate processing procedures and alloy additions are used. A review is made of work done by Japanese and other researchers on eutectoid and mildly hypereutectoid wires. A linear extrapolation of the tensile strength of fine wires predicts higher strengths at higher carbon contents. The influence of processing, alloy additions and carbon content in optimizing the strength, ductility and fracture behavior of hypereutectoid steels is presented. It is proposed that the tensile strength of pearlitic wires is dictated by the fracture strength of the carbide lamella at grain boundary locations in the carbide. Methods to improve the strength of carbide grain boundaries and to decrease the carbide plate thickness will contribute to enhancing the ultrahigh strength obtainable in hypereutectoid steel wires. 23 refs., 13 figs., 1 tab.

Lesuer, D.R.; Syn, C.K.; Sherby, O.D.; Kim, D.K.

1996-06-25T23:59:59.000Z

42

Mechanical Behavior Studies of Depleted Uranium in the Presence of Hydrides  

DOE Green Energy (OSTI)

This project addresses critical issues related to aging in the presence of hydrides (UH{sub 3}) in DU and the subsequent effect on mechanical behavior. Rolled DU specimens with three different hydrogen concentrations and the as-rolled condition were studied. The texture measurements indicate that the hydrogen charging is affecting the initial as-rolled DU microstructure/texture. The macroscopic mechanical behavior suggests the existence of a threshold between the 0 wpmm H and 0.3 wppm H conditions. A VPSC simulation of the macroscopic strain-stress behavior, when taking into account only a texture effect, shows no agreement with the experiment. This suggests that the macroscopic mechanical behavior observed is indeed due to the presence of hydrogen/hydrides in the DU bulk. From the lattice strain variation it can be concluded that the hydrogen is affecting the magnitude and/or the nature of CRSS. The metallography indicates the specimens that underwent the hydrogen charging process, developed large grains and twinning, which were enhanced by the presence of hydrogen. Further studies using electron microscopy and modeling will be conducted to learn about the deformation mechanisms responsible for the observed behavior.

Garlea, E.; Morrell, J. S.; Bridges, R. L.; Powell, G. L.; Brown, d. W.; Sisneros, T. A.; Tome, C. N.; Vogel, S. C.

2011-02-14T23:59:59.000Z

43

The effect of structural defects in SiC particles on the static & dynamic mechanical response of a 15 volume percent SiC/6061-Al matrix composite  

SciTech Connect

Static and Dynamic mechanical tests, and microstructural examinations performed on a SiC particle reinforced 6061-Al matrix composite indicated that particle cracking significantly affected the strength, strain hardening, and failure mechanism of the composite. Cracks were observed to nucleate and propagate on stacking faults and interfaces between the various phases within the reinforcing SiC particles. Planar defects were the predominant artifacts seen in the SiC particles. Partial dislocations were also observed bounding the stacking faults within the reinforcement phase.

Vaidya, R.U.; Song, S.G.; Zurek, A.K.; Gray, G.T. III

1995-09-01T23:59:59.000Z

44

The neuromolecular mechanisms that coordinate food availability with C. elegans male sexual behavior  

E-Print Network (OSTI)

Organisms must coordinate behavioral and physiological responses to changingenvironmental conditions. In the nematode C. elegans, the presence or absence of foodin the environment affects many metabolic and behavioral responses, including fathomeostasis, lifespan, and male mating. Specifically, male mating behavior normallyoccurs when a well-nourished male encounters a hermaphrodite, and is repressed if themale is under-nourished. To understand how environmental changes influence the driveto carry out specific behavioral tasks, I used C. elegans male mating as a model.Previously, mutants were isolated that display male mating behavior at inappropriatetimes, i.e. in the absence of mating cues. Loss of function mutations in the ERG K+channel, UNC-103, results in spontaneous seizures of the male sex muscles.Interestingly, I found that food deprivation can suppress unc-103(lf)-induced seizures,suggesting that pathways activated under this environmental condition can suppress theexcitability of the mating circuit.Using molecular, genetic, and behavioral assays, I identified sensory andmolecular mechanisms that reduce sex-muscle excitability under food-deprived conditions. I found that mutations that affect the muscular feeding organ, the pharynx,phenocopy the effects of food deprivation, and reduce sex-muscle excitability. Idemonstrated that mutations in the pharyngeal muscle protein, tropomyosin, cause thepharyngeal neurosecretory motor neurons (NSMs) to increase pharyngeal excitabilityand reduce sex-muscle excitability. Additionally, I found that olfactory neurons (AWCs)with sensory cilia exposed to the environment are up-regulated in the absence of foodstimuli, and also send inhibitory signals to the sex muscles. To determine howchemosensory and pharyngeal neurons in the head can signal to the genitalia, Ihypothesized that one mechanism could be via secretion of metabolic hormones. To testthis, I examined loss-of-function mutations in the insulin-like receptor, DAF-2, which isknown to regulate many behavioral and physiological responses to food. I demonstratedthat DAF-2 activity in the sex muscles is required for food-deprivation suppression ofunc-103(0)-induced seizures. I then identified components of a novel-insulin-like/DAF-2signaling pathway that reduces excitability. Specifically, I propose that ligand binding toDAF-2 activates PLC- and leads to increased cystolic Ca2+. This Ca2+ influx activatesCaMKII, which can phosphorylate/activate EAG-like K+ channels, thereby reducing cellexcitability.

Gruninger, Todd Ryan

2008-08-01T23:59:59.000Z

45

Shape Defects  

Science Conference Proceedings (OSTI)

...There are six major shape defects in coiled sheet, strip, or plate (Fig. 1): coil set; cross bow; camber;

46

NUMERICAL SIMULATION FOR MECHANICAL BEHAVIOR OF U10MO MONOLITHIC MINIPLATES FOR RESEARCH AND TEST REACTORS  

Science Conference Proceedings (OSTI)

This article presents assessment of the mechanical behavior of U-10wt% Mo (U10Mo) alloy based monolithic fuel plates subject to irradiation. Monolithic, plate-type fuel is a new fuel form being developed for research and test reactors to achieve higher uranium densities within the reactor core to allow the use of low-enriched uranium fuel in high-performance reactors. Identification of the stress/strain characteristics is important for understanding the in-reactor performance of these plate-type fuels. For this work, three distinct cases were considered: (1) fabrication induced residual stresses (2) thermal cycling of fabricated plates; and finally (3) transient mechanical behavior under actual operating conditions. Because the temperatures approach the melting temperature of the cladding during the fabrication and thermal cycling, high temperature material properties were incorporated to improve the accuracy. Once residual stress fields due to fabrication process were identified, solution was used as initial state for the subsequent simulations. For thermal cycling simulation, elasto-plastic material model with thermal creep was constructed and residual stresses caused by the fabrication process were included. For in-service simulation, coupled fluid-thermal-structural interaction was considered. First, temperature field on the plates was calculated and this field was used to compute the thermal stresses. For time dependent mechanical behavior, thermal creep of cladding, volumetric swelling and fission induced creep of the fuel foil were considered. The analysis showed that the stresses evolve very rapidly in the reactor. While swelling of the foil increases the stress of the foil, irradiation induced creep causes stress relaxation.

Hakan Ozaltun & Herman Shen

2011-11-01T23:59:59.000Z

47

Indentation-induced mechanical deformation behaviors of AlN thin films deposited on c-plane sapphire  

Science Conference Proceedings (OSTI)

The mechanical properties and deformation behaviors of AlN thin films deposited on c-plane sapphire substrates by helicon sputtering method were determined using the Berkovich nanoindentation and cross-sectional transmission electron microscopy (XTEM). ...

Sheng-Rui Jian; Jenh-Yih Juang

2012-01-01T23:59:59.000Z

48

An experimental investigation into the stress-dependent mechanical behavior of cohesive soil with application to wellbore instability  

E-Print Network (OSTI)

This thesis investigates the mechanical behavior of cohesive soils with reference to the applications of wellbore instabilities through an extensive program of laboratory element and model borehole tests. The laboratory ...

Abdulhadi, Naeem Omar

2009-01-01T23:59:59.000Z

49

Progress in understanding the mechanical behavior of pressure-vessel materials at elevated temperatures  

SciTech Connect

Progress during the 1970's on the production of high-temperature mechanical properties data for pressure vessel materials was reviewed. The direction of the research was toward satisfying new data requirements to implement advances in high-temperature inelastic design methods. To meet these needs, servo-controlled testing machines and high-resolution extensometry were developed to gain more information on the essential behavioral features of high-temperature alloys. The similarities and differences in the mechanical response of various pressure vessel materials were identified. High-temperature pressure vessel materials that have received the most attention included Type 304 stainless steel, Type 316 stainless steel, 2 1/4 Cr-1 Mo steel, alloy 800H, and Hastelloy X.

Swindeman, R.W.; Brinkman, C.R.

1981-01-01T23:59:59.000Z

50

Mechanism for radiative recombination and defect properties of GaP/GaNP core/shell nanowires  

SciTech Connect

Recombination processes in GaP/GaNP core/shell nanowires (NWs) grown on a Si substrate by molecular beam epitaxy are examined using a variety of optical characterization techniques, including cw- and time-resolved photoluminescence and optically detected magnetic resonance (ODMR). Superior optical quality of the structures is demonstrated based on the observation of intense emission from a single NW at room temperature. This emission is shown to originate from radiative transitions within N-related localized states. From ODMR, growth of GaP/GaNP NWs is also found to facilitate formation of complex defects containing a P atom at its core that act as centers of competing non-radiative recombination.

Dobrovolsky, A.; Stehr, J. E.; Chen, S. L.; Chen, W. M.; Buyanova, I. A. [Department of Physics, Chemistry and Biology, Linkoeping University, S-581 83 Linkoeping (Sweden); Kuang, Y. J. [Department of Physics, University of California, La Jolla, California 92093 (United States); Sukrittanon, S. [Graduate Program of Materials Science and Engineering, La Jolla, California 92093 (United States); Tu, C. W. [Department of Electrical and Computer Engineering, University of California, La Jolla, California 92093 (United States)

2012-10-15T23:59:59.000Z

51

Mechanical behavior at 20 and 1200 C of Nicalon-silicon-carbide-fiber-reinforced alumina-matrix composites  

SciTech Connect

Tensile and fracture tests were conducted at 20 and 1,200 C on a ceramic-matrix composite that was composed of an alumina (Al{sub 2}O{sub 3}) matrix that was bidirectionally reinforced with 37 vol% silicon carbide (SiC) Nicalon fibers. The composite presented nonlinear behavior at both temperatures; however, the strength and toughness were significantly reduced at 1,200 C. In accordance with this behavior, matrix cracks were usually stopped or deflected at the fiber/matrix interface, and fiber pullout was observed on the fracture surfaces at 20 and 1,200 C. The interfacial sliding resistance at ambient and elevated temperatures was estimated from quantitative microscopy analyses of the saturation crack spacing in the matrix. The in situ fiber strength was determined both from the defect morphology on the fibers and from the size of the mirror region on the fiber fracture surfaces. It was shown that composite degradation at elevated temperature was due to the growth of defects on the fiber surface during high-temperature exposure.

Celemin, J.A.; Pastor, J.Y.; Llorca, J.; Elices, M. [Polytechnic Univ. of Madrid (Spain). Dept. of Materials Science

1997-10-01T23:59:59.000Z

52

Aging behavior and mechanical properties of maraging steels in the presence of submicrocrystalline Laves phase particles  

SciTech Connect

Cold rolling and annealing of homogenized Fe-Ni-Mn-Mo-Ti-Cr maraging steels resulted in the formation of submicrocrystalline Fe{sub 2}(Mo,Ti) Laves phase particles. Optical and scanning electron microscopy, X-ray diffraction, tensile and hardness tests were used to study the microstructure, aging behavior and mechanical properties of the annealed steels. The annealed microstructures showed age hardenability during subsequent isothermal aging at 753 K. Ultrahigh fracture stress but poor tensile ductility was obtained after substantial age hardening in the specimens with 2% and 4% chromium. Increasing chromium addition up to 6% toughened the aged microstructure at the expense of the fracture stress by increasing the volume fraction of retained austenite. The Laves phase particles acted as crack nucleation sites during tensile deformation. - Highlights: {yields} Laves phases dispersed in a BCC iron matrix by annealing of cold rolled samples. {yields} The samples showed age hardenability during subsequent isothermal aging at 753 K. {yields} Ultrahigh fracture stress but poor ductility was obtained after age hardening. {yields} Increasing chromium addition toughened the aged microstructure. {yields} Laves phase particles acting as crack nucleation sites during tensile deformation.

Mahmoudi, A., E-mail: abbasm1363@gmail.com [Young Researchers Club, Ahar Branch, Islamic Azad University, P.O. Box 54516, Ahar (Iran, Islamic Republic of); Ghavidel, M.R. Zamanzad [Young Researchers Club, Ahar Branch, Islamic Azad University, P.O. Box 54516, Ahar (Iran, Islamic Republic of); Nedjad, S. Hossein [Faculty of Materials Engineering, Sahand University of Technology, P. O. Box: 51335-1996, Tabriz (Iran, Islamic Republic of); Heidarzadeh, A. [Young Researchers Club, Ahar Branch, Islamic Azad University, P.O. Box 54516, Ahar (Iran, Islamic Republic of); Ahmadabadi, M. Nili [School of Metallurgy and Materials Engineering, University of Tehran, P. O. Box: 14395-731, Tehran (Iran, Islamic Republic of)

2011-10-15T23:59:59.000Z

53

Theoretical assessment on the possibility of constraining point defect energetics by pseudo-phase transition pressures  

E-Print Network (OSTI)

Making use of the energetics and equations of state of defective uranium dioxide that calculated with first-principles method, we demonstrate a possibility of constraining the formation energy of point defects by measuring the transition pressures of the corresponding pseudo-phase of defects. The mechanically stable range of fluorite structure of UO2, which dictates the maximum possible pressure of relevant pseudo-phase transitions, gives rise to defect formation energies that span a wide band and overlap with the existing experimental estimates. We reveal that the knowledge about pseudo-phase boundaries can not only provide important information of energetics that is helpful for reducing the scattering in current estimates, but also be valuable for guiding theoretical assessments, even to validate or disprove a theory. In order to take defect interactions into account and to extrapolate the physical quantities at finite stoichiometry deviations to that near the stoichiometry, we develop a general formalism to describe the thermodynamics of a defective system. We also show that it is possible to include interactions among defects in a simple expression of point defect model (PDM) by introducing an auxiliary constant mean-field. This generalization of the simple PDM leads to great versatility that allows one to study nonlinear effects of stoichiometry deviation on materials' behavior. It is a powerful tool to extract the defect energetics from finite defect concentrations to the dilute limit. Besides these, the full content of the theoretical formalism and some relevant and interesting issues, including reentrant pseudo-transition, multi-defect coexistence, charged defects, and possible consequence of instantaneous defective response in a quantum crystal, are explored and discussed.

Hua Y. Geng; Hong X. Song; Q. Wu

2013-05-29T23:59:59.000Z

54

Defects and Properties of Cast Metals  

Science Conference Proceedings (OSTI)

Conference Tools for 2012 TMS Annual Meeting & Exhibition ... In many instances the mechanism for the generation of the defects arises from a combination of...

55

Discrete particle transport in porous media : discrete observations of physical mechanisms influencing particle behavior  

E-Print Network (OSTI)

An understanding of how discrete particles in the micron to submicron range behave in porous media is important to a number of environmental problems. Discrete particle behavior in the interior of a porous medium is complex ...

Yoon, Joon Sik, 1973-

2005-01-01T23:59:59.000Z

56

An examination of potential causal mechanisms linking genes and political behavior  

E-Print Network (OSTI)

727757. Dawes, C. & J. Fowler. 2009. Partisanship, Voting,and Brain Functions 3(2):114. Fowler, J. & C. Kam. 2006. Behavior 28:113128. Fowler, James H. & Christopher T.

Dawes, Christopher T.

2011-01-01T23:59:59.000Z

57

Effects of irradiation on the mechanical behavior of twined SiC nanowires  

SciTech Connect

Irradiation is known to bring new features in one-dimensional nano materials. In this study, we used molecular dynamics simulations to investigate the irradiation effects on twined SiC nanowires. Defects tend to accumulate from outside toward inside of the twined SiC nanowires with increasing irradiation dose, leading to a transition from brittle to ductile failure under tensile load. Atomic chains are formed in the ductile failure process. The first-principles calculations show that most of the atomic chains are metallic.

Jin Enze; Niu Lisha; Lin Enqiang; Duan Zheng [AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China)

2013-03-14T23:59:59.000Z

58

Mechanical behavior of tissue simulants and soft tissues under extreme loading conditions  

E-Print Network (OSTI)

Recent developments in computer-integrated surgery and in tissue-engineered constructs necessitate advances in experimental and analytical techniques in characterizing properties of mechanically compliant materials such ...

Kalcioglu, Zeynep Ilke

2013-01-01T23:59:59.000Z

59

Wave Mechanics: Behavior of a Distributed Electron Charge in an Atom  

E-Print Network (OSTI)

In Part one of this Paper a hypothesis is forwarded of the electron charge in an atom existing in a distributed form. To check it by methods of electrodynamics and mechanics (without invoking the formalism of quantum mechanics and the concepts of the wave function and of the operators), the potential, kinetic, and total energies were calculated for three states of the hydrogen atom, which were found to agree closely with the available experimental data. The Part two of the Paper offers additional assumptions concerning various scenarios of motion of elements of the distributed electron charge which obey fully the laws of theoretical mechanics. The angular momentum of the ground-state hydrogen atom calculated in the frame of theoretical mechanics is shown to coincide with the spin which is $\\hbar/2$.

Andrey Vasilyev

2013-04-04T23:59:59.000Z

60

Role of the precentral cortex in adapting behavior to different mechanical environments  

E-Print Network (OSTI)

We routinely produce movements under different mechanical contexts. All interactions with the physical environment, such as swinging a hammer or lifting a carton of milk, alter the forces experienced during movement. With ...

Richardson, Andrew Garmory, 1977-

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Quantum fields with topological defects  

E-Print Network (OSTI)

Domain walls, strings and monopoles are extended objects, or defects, of quantum origin with topologically non--trivial properties and macroscopic behavior. They are described in Quantum Field Theory in terms of inhomogeneous condensates. We review the related formalism in the framework of the spontaneous breakdown of symmetry.

M. Blasone; P. Jizba; G. Vitiello

2004-02-13T23:59:59.000Z

62

Defect-deformation mechanism of the size effect in the laser-induced formation of microstructures of the brass surface relief in liquid  

Science Conference Proceedings (OSTI)

It is shown that the model of the defect-deformation instability describes the recently found linear dependence of the period of ordered surface relief microstructures, produced on brass in liquid upon multipulse laser ablation, on the radius of the spot on the target surface. (letters)

Emel'yanov, V I [M. V. Lomonosov Moscow State University, Faculty of Physics, Moscow (Russian Federation)

2008-07-31T23:59:59.000Z

63

Size, effect of flexible proof mass on the mechanical behavior of micron-scale cantilevers for energy harvesting appications.  

Science Conference Proceedings (OSTI)

Mechanical behavior of micron-scale cantilevers with a distributed, flexible proof mass is investigated to understand proof mass size effects on the performance of microelectromechanical system energy harvesters. Single-crystal silicon beams with proof masses of various lengths were fabricated using focused ion beam milling and tested using atomic force microscopy. Comparison of three different modeling results with measured data reveals that a 'two-beam' method has the most accurate predictive capability in terms of both resonant frequency and strain. Accurate strain prediction is essential because energy harvested scales with strain squared and maximum strain will be a design limit in fatigue.

Kim, M.; Hong, S.; Miller, D. J.; Dugundji, J.; Wardle, B. L. (Materials Science Division); (MIT)

2011-12-15T23:59:59.000Z

64

Theoretical Investigation on Interplay of Defect Clusters and Fission ...  

Science Conference Proceedings (OSTI)

A prominent effect of the self-defect clusters in bulk matrix on the thermodynamic behavior of fission gases is found, a thermodynamic competition between the...

65

Electron tomography of defects  

E-Print Network (OSTI)

semiconductor specimens with sufficiently low amounts of damage as to give some area with defect structure typical of the material before sample preparation. A similar study in brass [18] (more ductile, with more damage expected) found the maximum depth... for these samples [19]. As seen by comparing silicon and brass, subjecting a ductile material to abrasion causes much deeper disruption than in a brittle material, as energy is diverted to plastic deformation. 1.3.2 Non-mechanical shaping methods Spark cutting may...

Sharp, Joanne

2010-10-12T23:59:59.000Z

66

3D Simulation of Missing Pellet Surface Defects in Light Water Reactor Fuel Rods  

Science Conference Proceedings (OSTI)

The cladding on light water reactor (LWR) fuel rods provides a stable enclosure for fuel pellets and serves as a first barrier against fission product release. Consequently, it is important to design fuel to prevent cladding failure due to mechanical interactions with fuel pellets. Cladding stresses can be effectively limited by controlling power increase rates. However, it has been shown that local geometric irregularities caused by manufacturing defects known as missing pellet surfaces (MPS) in fuel pellets can lead to elevated cladding stresses that are sufficiently high to cause cladding failure. Accurate modeling of these defects can help prevent these types of failures. Nuclear fuel performance codes commonly use a 1.5D (axisymmetric, axially-stacked, one-dimensional radial) or 2D axisymmetric representation of the fuel rod. To study the effects of MPS defects, results from 1.5D or 2D fuel performance analyses are typically mapped to thermo-mechanical models that consist of a 2D plane-strain slice or a full 3D representation of the geometry of the pellet and clad in the region of the defect. The BISON fuel performance code developed at Idaho National Laboratory employs either a 2D axisymmetric or 3D representation of the full fuel rod. This allows for a computational model of the full fuel rod to include local defects. A 3D thermo-mechanical model is used to simulate the global fuel rod behavior, and includes effects on the thermal and mechanical behavior of the fuel due to accumulation of fission products, fission gas production and release, and the effects of fission gas accumulation on thermal conductivity across the fuel-clad gap. Local defects can be modeled simply by including them in the 3D fuel rod model, without the need for mapping between two separate models. This allows for the complete set of physics used in a fuel performance analysis to be included naturally in the computational representation of the local defect, and for the effects of the local defect to be coupled with the global fuel rod model. This approach for modeling fuel with MPS defects is demonstrated and compared with alternative techniques. The effects of varying parameters of the MPS defect are studied using this technique and presented here.

B.W. Spencer; J.D. Hales; S.R. Novascone; R.L. Williamson

2012-09-01T23:59:59.000Z

67

Creep Behavior and Deformation Mechanisms for Nanocluster-Strengthened Ferritic Steels  

Science Conference Proceedings (OSTI)

Mechanically alloyed, nanostructured ferritic steels represent a class of alloys that can display high resistance to radiation and creep deformation, which are derived from the presence of nanoclusters, precipitates and solute segregation to the grain boundaries. The creep responses for a 14YWT nanostructured ferritic steel were measured over a range of temperatures and stress levels. The stress exponent was observed to vary non-linearly with applied stress; stress exponents were found to decrease with decreasing stress approaching unity at low stress. Transmission electron microscopy studies clearly demonstrated that creep deformation proceeds by a dislocation glide within nanoscale grains and that glide dislocations are attracted to and pinned by nanoclusters. In light of these observations, a new model of the creep response, inspired by the Kocks-Argon-Ashby model, is developed to explain the low creep rates and small stress exponents that are exhibited by these alloys.

Brandes, Matthew C [Ohio State University; Kovarik, L. [Ohio State University; Miller, Michael K [ORNL; Daehn, Glenn [Ohio State University; Mills, Michael J. [Ohio State University

2011-01-01T23:59:59.000Z

68

Fundamental studies of the effect of crystal defects on CuInSe{sub 2}/CdS heterojunction behavior: Final report, 28 June 1993--30 June 1998  

DOE Green Energy (OSTI)

This report describes the work performed by the University of Illinois at Urbana-Champaign. The following results were obtained under the work funded by this subcontract: (1) Point defects and electronic properties of Cu(In{sub 1-x}Ga{sub x})Se{sub 2}: New record results for hole mobilities in Cu(In{sub 1-x}Ga{sub x})Se{sub 2} based on single crystals grown by Rockett's group; Demonstrated the role of Ga in determining hole concentrations; Showed that Ga does not affect the hole mobility in this material and why this is the case; Determined the diffusion coefficient for Ga in single-crystal Cu(In{sub 1-x}Ga{sub x})Se{sub 2}; Demonstrated the structure and optoelectronic properties of the CuIn{sub 3}Se{sub 5} ordered-defect phase of CuInSe{sub 2}; Characterized the detailed effects of Na on Cu(In{sub 1-x}Ga{sub x})Se{sub 2} solar cells and on the fundamental properties of the material itself (reduces compensating donors in p-type materials); and In collaboration with groups at the Universities of Salford and Liverpool in the United Kingdom, studied the effect of ion implantation damage on Cu(In{sub 1-x}Ga{sub x})Se{sub 2} single-crystals. (2) Materials for and characterization of devices: Developed a novel contact metallurgy that improves adhesion to the underlying Mo back-contact in solar cells made with Cu(In{sub 1-x}Ga{sub x})Se{sub 2}; (This material has also yielded substantial novel materials science behaviors, including grain rotation and growth prior to phase separation in a metastable binary alloy.) Characterized the electroluminescence as a function of temperature and Ga content in Cu(In{sub 1-x}Ga{sub x})Se{sub 2} solar cells and showed that the radiative recombination pathways are not band-to-band as in normal semiconductors, but rather, proceed through defect states; and Working with a group at the University of Uppsala in Sweden, demonstrated novel aspects of the bonding and chemistry of dip-coated CdS heterojunction materials used as heterojunction partner materials in Cu(In{sub 1-x}Ga{sub x})Se{sub 2} solar cells.

Rockett, A.

1999-11-17T23:59:59.000Z

69

Final Technical Report of project: "Contactless Real-Time Monitoring of Paper Mechanical Behavior During Papermaking"  

SciTech Connect

The early precursors of laser ultrasonics on paper were Prof. Y. Berthelot from the Georgia Institute of Technology/Mechanical Engineering department, and Prof. P. Brodeur from the Institute of Paper Science and Technology, both located in Atlanta, Georgia. The first Ph.D. thesis that shed quite some light on the topic, but also left some questions unanswered, was completed by Mont A. Johnson in 1996. Mont Johnson was Prof. Berthelot's student at Georgia Tech. In 1997 P. Brodeur proposed a project involving himself, Y. Berthelot, Dr. Ken Telschow and Mr. Vance Deason from INL, Honeywell-Measurex and Dr. Rick Russo from LBNL. The first time the proposal was not accepted and P. Brodeur decided to re-propose it without the involvement from LBNL. Rick Russo proposed a separate project on the same topic on his side. Both proposals were finally accepted and work started in the fall of 1997 on the two projects. Early on, the biggest challenge was to find an optical detection method which could detect laser-induced displacements of the web surface that are of the order of .1 micron in the ultrasonic range. This was to be done while the web was having an out-of-plane amplitude of motion in the mm range due to web flutter; while moving at 10 m/s to 30 m/s in the plane of the web, on the paper machine. Both teams grappled with the same problems and tried similar methods in some cases, but came up with two similar but different solutions one year later. The IPST, GT, INL team found that an interferometer made by Lasson Technologies Inc. using the photo-induced electro-motive force in Gallium Arsenide was able to detect ultrasonic waves up to 12-15 m/s. It also developed in house an interferometer using the Two-Wave Mixing effect in photorefractive crystals that showed good promises for on-line applications, and experimented with a scanning mirror to reduce motion-induced texture noise from the web and improve signal to noise ratio. On its side, LBNL had the idea to combine a commercial Mach-Zehnder interferometer to a spinning mirror synchronized to the web speed, in order to make almost stationary measurements. The method was demonstrated at up to 10 m/s. Both teams developed their own version of a web simulator that was driving a web of paper at 10 m/s or higher. The Department of Energy and members of the Agenda 2020 started to make a push for merging the two projects. This made sense because their topics were really identical but this was not well received by Prof. Brodeur. Finally IPST decided to reassign the direction of the IPST-INL-GT project in the spring of 1999 to Prof. Chuck Habeger so that the two teams could work together. Also at this time, Honeywell-Measurex dropped as a member of the team. It was replaced by ABB Industrial Systems whose engineers had extensive previous experience of working with ultrasonic sensors on paperboard. INL also finished its work on the project as its competencies were partly redundant with LBNL. From the summer of 1999, the IPST-GT and LBNL teams were working together and helped each other often by collaborating and visiting either laboratory when was necessary. Around the beginning of 2000, began an effort at IPST to create an off-line laser-ultrasonics instrument that could perform automated measurements of paper and paperboard's bending stiffness. It was widely known that the mechanical bending tests of paper used for years by the paper industry were very inaccurate and exhibited poor reproducibility; therefore the team needed a new instrument of reference to validate its future on-line results. In 1999-2000, the focus of the on-line instrument was on a pre-industrial demonstration on a pilot coater while reducing the damage to the web caused by the generation laser, below the threshold where it could be visible by the naked eye. During the spring of 2000 Paul Ridgway traveled to IPST and brought with him a redesigned system still using the same Mach-Zehnder interferometer as before, but this time employing an electric motor-driven spinning mirror instead of the previously belt-driven m

Emmanuel Lafond; Paul Ridgway; Ted Jackson; Rick Russo; Ken Telschow; Vance Deason; Yves Berthelot; David Griggs; Xinya Zhang; Gary Baum

2005-08-30T23:59:59.000Z

70

Shedding Light on Nanocrystal Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Shedding Light on Nanocrystal Defects Print Shedding Light on Nanocrystal Defects Print Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their resistance to stress has had researchers proposing nanocrystals as a promising new protective coating for advanced gas turbine and jet engines. But recent studies conducted at the ALS show that the tiny size of nanocrystals does not safeguard them from defects. Engineering Nanocrystal Materials Most nanocrystal materials are made up of small crystals, called "grains," and what happens at the boundaries between these grains is critical to material properties. Based on computer simulations and electron microscopy analysis, the belief has been that dislocation-mediated plastic deformation becomes inactive below a grain size of at least 10 nanometers, and possibly as large as 30 nanometers.

71

Shedding Light on Nanocrystal Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Shedding Light on Nanocrystal Defects Print Shedding Light on Nanocrystal Defects Print Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their resistance to stress has had researchers proposing nanocrystals as a promising new protective coating for advanced gas turbine and jet engines. But recent studies conducted at the ALS show that the tiny size of nanocrystals does not safeguard them from defects. Engineering Nanocrystal Materials Most nanocrystal materials are made up of small crystals, called "grains," and what happens at the boundaries between these grains is critical to material properties. Based on computer simulations and electron microscopy analysis, the belief has been that dislocation-mediated plastic deformation becomes inactive below a grain size of at least 10 nanometers, and possibly as large as 30 nanometers.

72

Shedding Light on Nanocrystal Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Shedding Light on Nanocrystal Defects Print Shedding Light on Nanocrystal Defects Print Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their resistance to stress has had researchers proposing nanocrystals as a promising new protective coating for advanced gas turbine and jet engines. But recent studies conducted at the ALS show that the tiny size of nanocrystals does not safeguard them from defects. Engineering Nanocrystal Materials Most nanocrystal materials are made up of small crystals, called "grains," and what happens at the boundaries between these grains is critical to material properties. Based on computer simulations and electron microscopy analysis, the belief has been that dislocation-mediated plastic deformation becomes inactive below a grain size of at least 10 nanometers, and possibly as large as 30 nanometers.

73

Shedding Light on Nanocrystal Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Shedding Light on Nanocrystal Defects Print Shedding Light on Nanocrystal Defects Print Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their resistance to stress has had researchers proposing nanocrystals as a promising new protective coating for advanced gas turbine and jet engines. But recent studies conducted at the ALS show that the tiny size of nanocrystals does not safeguard them from defects. Engineering Nanocrystal Materials Most nanocrystal materials are made up of small crystals, called "grains," and what happens at the boundaries between these grains is critical to material properties. Based on computer simulations and electron microscopy analysis, the belief has been that dislocation-mediated plastic deformation becomes inactive below a grain size of at least 10 nanometers, and possibly as large as 30 nanometers.

74

Shedding Light on Nanocrystal Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Shedding Light on Nanocrystal Shedding Light on Nanocrystal Defects Shedding Light on Nanocrystal Defects Print Thursday, 20 June 2013 10:41 Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their resistance to stress has had researchers proposing nanocrystals as a promising new protective coating for advanced gas turbine and jet engines. But recent studies conducted at the ALS show that the tiny size of nanocrystals does not safeguard them from defects. Engineering Nanocrystal Materials Most nanocrystal materials are made up of small crystals, called "grains," and what happens at the boundaries between these grains is critical to material properties. Based on computer simulations and electron microscopy analysis, the belief has been that dislocation-mediated plastic deformation becomes inactive below a grain size of at least 10 nanometers, and possibly as large as 30 nanometers.

75

Shedding Light on Nanocrystal Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Shedding Light on Nanocrystal Defects Print Shedding Light on Nanocrystal Defects Print Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their resistance to stress has had researchers proposing nanocrystals as a promising new protective coating for advanced gas turbine and jet engines. But recent studies conducted at the ALS show that the tiny size of nanocrystals does not safeguard them from defects. Engineering Nanocrystal Materials Most nanocrystal materials are made up of small crystals, called "grains," and what happens at the boundaries between these grains is critical to material properties. Based on computer simulations and electron microscopy analysis, the belief has been that dislocation-mediated plastic deformation becomes inactive below a grain size of at least 10 nanometers, and possibly as large as 30 nanometers.

76

Mechanical Behavior Characterization  

Science Conference Proceedings (OSTI)

Oct 10, 2012 ... Program Organizers: Michael Gao, National Energy Technology Lab; Peter Liaw, University of Tennessee Wednesday 8:00 AM October 10...

77

Behavior of a quasi-isotropic ply metal matrix composite under thermo-mechanical and isothermal fatigue loading. Master's thesis  

Science Conference Proceedings (OSTI)

This study investigated the behavior of the SCS6/Ti-15-3 metal matrix composite with a quasi-isotropic layup when tested under static and fatigue conditions. Specimens were subjected to in-phase and out-of-phase thermo-mechanical and isothermal fatigue loading. In-phase and isothermal loading produced a fiber dominated failure while the out-of-phase loading produced a matrix dominated failure. Also, fiber domination in all three profiles was present at higher maximum applied loads and al three profiles demonstrated matrix domination at lower maximum applied loads. Thus, failure is both profile dependent and load equipment. Additional analyses, using laminated plate theory, Halpin-Tsai equations, METCAN, and the Linear Life Fraction Model (LLFM), showed: the as-received specimens contained plies where a portion of the fibers are debonded from the matrix; during fatigue cycling, the 90 deg. plies and a percentage of the 45 deg. plies failed immediately with greater damage becoming evident with additional cycles; and, the LLFM suggests that there may be a non-linear combination of fiber and matrix domination for in-phase and isothermal cycling.

Hart, K.A.

1992-12-01T23:59:59.000Z

78

Characterization of High Strain Rate Mechanical behavior of AZ31 magnesium alloy using 3D Digital Image Correlation  

Science Conference Proceedings (OSTI)

Characterization of the material mechanical behavior at sub-Hopkinson regime (0.1 to 1000 s{sup -1}) is very challenging due to instrumentation limitations and the complexity of data analysis involved in dynamic loading. In this study, AZ31 magnesium alloy sheet specimens are tested using a custom designed servo-hydraulic machine in tension at nominal strain rates up to 1000 s{sup -1}. In order to resolve strain measurement artifacts, the specimen displacement is measured using 3D Digital Image correlation instead from actuator motion. The total strain is measured up to {approx} 30%, which is far beyond the measurable range of electric resistance strain gages. Stresses are calculated based on the elastic strains in the tab of a standard dog-bone shaped specimen. Using this technique, the stresses measured for strain rates of 100 s{sup -1} and lower show little or no noise comparing to load cell signals. When the strain rates are higher than 250 s{sup -1}, the noises and oscillations in the stress measurements are significantly decreased from {approx} 250 to 50 MPa. Overall, it is found that there are no significant differences in the elongation, although the material exhibits slight work hardening when the strain rate is increased from 1 to 100 s{sup -1}.

Wang, Yanli [ORNL; Xu, Hanbing [ORNL; ERDMAN III, DONALD L [ORNL; Starbuck, J Michael [ORNL; Simunovic, Srdjan [ORNL

2011-01-01T23:59:59.000Z

79

Investigation of thermal, mechanical and magnetic behaviors of the Cu-11%Al alloy with Ag and Mn additions  

SciTech Connect

The investigation of thermal, mechanical and magnetic behaviors of the Cu-11%Al, Cu-11%Al-3%Ag, Cu-11%Al-10%Mn and Cu-11%Al-10%Mn-3%Ag alloys was made using microhardness measurements, differential scanning calorimetry, X-ray diffractometry, scanning electron microscopy, energy dispersion X-ray spectroscopy and magnetic moment change with applied field measurement. The results indicated that the Mn addition changes the phase stability range, the microhardness values and makes undetectable the eutectoid reaction in annealed Cu-11%Al and Cu-11%Al-3%Ag alloys while the presence of Ag does not modify the phase transformation sequence neither microhardness values of the annealed Cu-11%Al and Cu-11%Al-10%Mn alloys, but it increases the magnetic moment of this latter at about 2.7 times and decreases the rates of eutectoid and peritectoid reactions of the former. - Highlights: Black-Right-Pointing-Pointer The microstructure of Cu-Al alloy is modified in the Ag presence. Black-Right-Pointing-Pointer ({alpha} + {gamma}) phase is stabilized down to room temperature when Ag is added to Cu-Al alloy. Black-Right-Pointing-Pointer Ag-rich phase modifies the magnetic characteristics of Cu-Al-Mn alloy.

Silva, R.A.G., E-mail: galdino.ricardo@gmail.com [Departamento de Ciencias Exatas e da Terra-UNIFESP, Diadema-SP (Brazil)] [Departamento de Ciencias Exatas e da Terra-UNIFESP, Diadema-SP (Brazil); Paganotti, A.; Gama, S. [Departamento de Ciencias Exatas e da Terra-UNIFESP, Diadema-SP (Brazil)] [Departamento de Ciencias Exatas e da Terra-UNIFESP, Diadema-SP (Brazil); Adorno, A.T.; Carvalho, T.M.; Santos, C.M.A. [Instituto de Quimica - UNESP, Araraquara-SP (Brazil)] [Instituto de Quimica - UNESP, Araraquara-SP (Brazil)

2013-01-15T23:59:59.000Z

80

Mechanism of the hysteretic behavior of the magnetoresistance of granular HTSCs: The universal nature of the width of the magnetoresistance hysteresis loop  

Science Conference Proceedings (OSTI)

The hysteretic behavior of the magnetoresistance R(H) of granular high-temperature superconductors (HTSCs) of the Y-Ba-Cu-O, Bi-Ca-Sr-Cu-O, and La-Sr-Cu-O classical systems is investigated for transport current densities lower and higher than the critical density (at H = 0). All systems exhibit universal behavior of the width of the magnetoresistance hysteresis loop: independence of transport current under identical external conditions. This means that flux trapping in HTSC grains is the main mechanism controlling the hysteretic behavior of the magnetoresistance of granular HTSCs, while pinning of Josephson vortices in the intragranular medium makes no appreciable contribution to the formation of magnetoresistance hysteresis (when transport current flows through the sample). Experimental data on relaxation of residual resistance after the action of a magnetic field also confirm this conclusion.

Balaev, D. A., E-mail: smp@iph.krasn.ru; Dubrovskii, A. A.; Shaikhutdinov, K. A.; Popkov, S. I.; Gokhfeld, D. M.; Gokhfeld, Yu. S.; Petrov, M. I. [Russian Academy of Sciences, Kirenskii Institute of Physics, Siberian Branch (Russian Federation)

2009-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Modelling of thermo-mechanical and irradiation behavior of metallic and oxide fuels for sodium fast reactors  

E-Print Network (OSTI)

A robust and reliable code to model the irradiation behavior of metal and oxide fuels in sodium cooled fast reactors is developed. Modeling capability was enhanced by adopting a non-empirical mechanistic approach to the ...

Karahan, Aydin

2009-01-01T23:59:59.000Z

82

Modeling rough energy landscapes in defected condensed matter  

E-Print Network (OSTI)

This dissertation is a computational and theoretical investigation of the behavior of defected condensed matter and its evolution over long time scales. The thesis provides original contributions to the methodology used ...

Monasterio Velsquez, Paul Rene

2010-01-01T23:59:59.000Z

83

The elevated-temperature mechanical behavior of as-cast and wrought Ti-6Al-4V-1B  

Science Conference Proceedings (OSTI)

This work studied the effect of processing on the elevated-temperature [728 K (455 C)] fatigue deformation behavior of Ti-6Al-4V-1B for maximum applied stresses between 300 to 700 MPa (R = 0.1, 5 Hz). The alloy was evaluated in the as-cast form as well as in three wrought forms: cast-and-extruded, powder metallurgy (PM) rolled, and PM extruded. Processing caused significant differences in the microstructure, which in turn impacted the fatigue properties. The PM-extruded material exhibited a fine equiaxed {alpha} + {beta} microstructure and the greatest fatigue resistance among all the studied materials. The {beta}-phase field extrusion followed by cooling resulted in a strong {alpha}-phase texture in which the basal plane was predominately oriented perpendicular to the extrusion axis. The TiB whiskers were also aligned in the extrusion direction. The {alpha}-phase texture in the extrusions resulted in tensile-strength anisotropy. The tensile strength in the transverse orientation was lower than that in the longitudinal orientation, but the strength in the transverse orientation remained greater than that for the as-cast Ti-6Al-4V. The ratcheting behavior during fatigue is also discussed.

Chen, Wei [ORNL; Boehlert, C. J. [Michigan State University, East Lansing; Howe, Jane Y [ORNL; Payzant, E Andrew [ORNL

2011-01-01T23:59:59.000Z

84

Application of the multi-mechanism deformation model for three-dimensional simulations of salt : behavior for the strategic petroleum reserve.  

Science Conference Proceedings (OSTI)

The U.S. Strategic Petroleum Reserve stores crude oil in 62 solution-mined caverns in salt domes located in Texas and Louisiana. Historically, three-dimensional geomechanical simulations of the behavior of the caverns have been performed using a power law creep model. Using this method, and calibrating the creep coefficient to field data such as cavern closure and surface subsidence, has produced varying degrees of agreement with observed phenomena. However, as new salt dome locations are considered for oil storage facilities, pre-construction geomechanical analyses are required that need site-specific parameters developed from laboratory data obtained from core samples. The multi-mechanism deformation (M-D) model is a rigorous mathematical description of both transient and steady-state creep phenomena. Recent enhancements to the numerical integration algorithm within the model have created a more numerically stable implementation of the M-D model. This report presents computational analyses to compare the results of predictions of the geomechanical behavior at the West Hackberry SPR site using both models. The recently-published results using the power law creep model produced excellent agreement with an extensive set of field data. The M-D model results show similar agreement using parameters developed directly from laboratory data. It is also used to predict the behavior for the construction and operation of oil storage caverns at a new site, to identify potential problems before a final cavern layout is designed.

Ehgartner, Brian L.; Sobolik, Steven Ronald; Bean, James E.

2010-07-01T23:59:59.000Z

85

Interactions of structural defects with metallic impurities in multicrystalline silicon  

DOE Green Energy (OSTI)

Interactions between structural defects and metallic impurities were studied in multicrystalline silicon for solar cells applications. The objective was to gain insight into the relationship between solar cell processing, metallic impurity behavior and the resultant effect on material/device performance. With an intense synchrotron x-ray source, high sensitivity x-ray fluorescence measurements were utilized to determine impurity distributions with a spatial resolution of {approx} 1{micro}m. Diffusion length mapping and final solar cell characteristics gauged material/device performance. The materials were tested in both the as-grown state and after full solar cell processing. Iron and nickel metal impurities were located at structural defects in as-grown material, while after solar cell processing, both impurities were still observed in low performance regions. These results indicate that multicrystalline silicon solar cell performance is directly related to metal impurities which are not completely removed during typical processing treatments. A discussion of possible mechanisms for this incomplete removal is presented.

McHugo, S.A. [Lawrence Berkeley National Lab., CA (US). Advanced Light Source; Hieslmair, H.; Weber, E.R. [Univ. of California, Berkeley, CA (US). Dept. of Materials Science and Mineral Engineering; Rosenblum, M.D.; Kalejs, J.P. [ASE Americas Inc., Billerica, MA (US)

1996-11-01T23:59:59.000Z

86

Microstructural Characterization of the Chemo-mechanical Behavior of Asphalt in Terms of Aging and Fatigue Performance Properties  

E-Print Network (OSTI)

The study of asphalt chemo-mechanics requires a basic understanding of the physical properties and chemical composition of asphalt and how these properties are linked to changes in performance induced by chemical modifications. This work uniquely implements the framework of chemo-mechanics by investigating two types of chemical modification processes, natural (oxidative aging) and synthetic (chemical doping) as they relate not only to macro-scale properties of asphalt binder but also to the asphalt microstructure and nanorheology. Furthermore, this study demonstrates the application of atomic force microscopy (AFM) imaging and the extraction of nano-scale engineering properties, i.e. elastic modulus, relaxation modulus, and surface energy, as a method to predict performance related to the fatigue characteristics of asphalt binders by modeling intrinsic material flaws present amongst phase interfaces. It was revealed that oxidative aging induces substantial microstructural changes in asphalt, including variations in phase structure, phase properties, and phase distribution. It has also been shown that certain asphalt chemical parameters have a consistent and measureable effect on the asphalt microstructure that is observed with AFM. In fact, particular phases that emerged via chemical doping revealed a surprising correlation between oxidative aging and the saturates chemical parameter of asphalt in terms of how they explicitly impact durability and performance of asphalt. By implementing a crack initiation model which requires measureable microstructural characteristics as an input parameter it was found that microstructural flaws (depending on the extremity) can have a more profound impact on asphalt performance than the properties of the material located between the flaws. It was also discovered by comparing the findings to performance data in the Strategic Highway Research Programs (SHRPs) Materials Reference Library (MRL), that the crack initiation model predicts very similar performance as the SHRPs distress resistance indicators. Overall, this body of work yields improved input values for asphalt prediction models and serves as the basis for ongoing studies in the areas of asphalt chemical mapping, modeling of nano-damage, and nano-modification using AFM.

Allen, Robert Grover

2013-05-01T23:59:59.000Z

87

Constitutive Model for the Time-Dependent Mechanical Behavior of 430 Stainless Steel and FeCrAlY Foams in Sulfur-Bearing Environments  

Science Conference Proceedings (OSTI)

The mechanical behavior of 430 stainless steel and pre-oxidized FeCrAlY open-cell foam materials of various densities was evaluated in compression at temperatures between 450 C and 600 C in an environment containing hydrogen sulfide and water vapor. Both materials showed negligible corrosion due to the gaseous atmosphere for up to 168 hours. The monotonic stress-strain response of these materials was found to be dependent on both the strain rate and their density, and the 430 stainless steel foam materials exhibited less stress relaxation than FeCrAlY for similar experimental conditions. Using the results from multiple hardening-relaxation and monotonic tests, an empirical constitutive equation was derived to predict the stress-strain behavior of FeCrAlY foams as a function of temperature and strain rate. These results are discussed in the context of using these materials in a black liquor gasifier to accommodate the chemical expansion of the refractory liner resulting from its reaction with the soda in the black liquor.

Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL

2013-01-01T23:59:59.000Z

88

Flow in porous media, phase behavior and ultralow interfacial tensions: mechanisms of enhanced petroleum recovery. Final technical report  

Science Conference Proceedings (OSTI)

A major program of university research, longer-ranged and more fundamental in approach than industrial research, into basic mechanisms of enhancing petroleum recovery and into underlying physics, chemistry, geology, applied mathematics, computation, and engineering science has been built at Minnesota. The 1982 outputs of the interdisciplinary team of investigators were again ideas, instruments, techniques, data, understanding and skilled people: forty-one scientific and engineering papers in leading journals; four pioneering Ph.D. theses; numerous presentations to scientific and technical meetings, and to industrial, governmental and university laboratories; vigorous program of research visits to and from Minnesota; and two outstanding Ph.D.'s to research positions in the petroleum industry, one to a university faculty position, one to research leadership in a governmental institute. This report summarizes the 1982 papers and theses and features sixteen major accomplishments of the program during that year. Abstracts of all forty-five publications in the permanent literature are appended. Further details of information transfer and personnel exchange with industrial, governmental and university laboratories appear in 1982 Quarterly Reports available from the Department of Energy and are not reproduced here. The Minnesota program continues in 1983, notwithstanding earlier uncertainty about the DOE funding which finally materialized and is the bulk of support. Supplemental grants-in-aid from nine companies in the petroleum industry are important, as are the limited University and departmental contributions. 839 references, 172 figures, 29 tables.

Davis, H.T.; Scriven, L.E.

1982-01-01T23:59:59.000Z

89

Mechanical Behavior and Deformation Mechanisms of ...  

Science Conference Proceedings (OSTI)

To this end, bulk Ni samples were processed by SPS with emphasis on porosity elimination and microstructure reproducibility. The nano/micro volume fractions...

90

Influence of Process Induced Defects  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials, Processes and Applications for Additive ... Process induced defects were characterized by computer tomography (CT),...

91

Nested Domain Defects  

E-Print Network (OSTI)

An example of a supersymmetric model involving two interacting chiral superfields is presented here which allows for solutions describing string-like ``domain ribbon'' defects embedded within a domain wall. It is energetically favorable for the fermions within the wall to populate the domain ribbons, and an explicit solution is found for the fermion zero modes. The Fermi gas within ribbons can allow them to stabilize in the form of small loops.

J. R. Morris

1997-07-30T23:59:59.000Z

92

Mechanical Behavior of Reactor Materials  

Science Conference Proceedings (OSTI)

Mar 12, 2012... for application in the secondary heat exchanger of the New Generation ... active loaded compact tension specimens with CW levels of 0-28%.

93

Mechanical Behavior and Physical Metallurgy  

Science Conference Proceedings (OSTI)

Mar 2, 2011 ... This research is sponsored by the U.S. DOE, Office of EERE Industrial Technologies Program, and the LDRD Program of Oak Ridge National...

94

Mechanical Behavior of Indium Nanostructures  

NLE Websites -- All DOE Office Websites (Extended Search)

materials such as indium, since conventional pillar fabrication by focused ion-beam milling techniques ultimately leads to melting or structural degradation. All indium...

95

Mechanical Behavior of Nanoporous Materials  

Science Conference Proceedings (OSTI)

Unconventional Short-Term Glow Discharge Nitriding of 316l Austenitic Steel Using Accumulative Roll Bonding to Process Ultrafine Grained...

96

Mechanical Behavior - Programmaster.org  

Science Conference Proceedings (OSTI)

Oct 31, 2013 ... Effect of Prior Fatigue Exposure on Creep Rupture Strength of Grade 92 ... Influence of Loading Path Changes on Texture and Internal Strain in Rolled ... 1

97

Mechanical Behavior of Nanoporous Pt  

Science Conference Proceedings (OSTI)

Piezoelectric Smart Composites: Electromechanical Properties and Design Maps Preparation of ... Research on Aluminum Foam Railway Noise Barrier.

98

Role of defects in III-nitride based electronics  

DOE Green Energy (OSTI)

The LDRD entitled ``Role of Defects in III-Nitride Based Devices'' is aimed to place Sandia National Laboratory at the forefront of the field of GaN materials and devices by establishing a scientific foundation in areas such as material growth, defect characterization/modeling, and processing (metalization and etching) chemistry. In this SAND report the authors summarize their studies such as (1) the MOCVD growth and doping of GaN and AlGaN, (2) the characterization and modeling of hydrogen in GaN, including its bonding, diffusion, and activation behaviors, (3) the calculation of energetic of various defects including planar stacking faults, threading dislocations, and point defects in GaN, and (4) dry etching (plasma etching) of GaN (n- and p-types) and AlGaN. The result of the first AlGaN/GaN heterojunction bipolar transistor is also presented.

HAN,JUNG; MYERS JR.,SAMUEL M.; FOLLSTAEDT,DAVID M.; WRIGHT,ALAN F.; CRAWFORD,MARY H.; LEE,STEPHEN R.; SEAGER,CARLETON H.; SHUL,RANDY J.; BACA,ALBERT G.

2000-01-01T23:59:59.000Z

99

IC defect sensitivity for footprint-type spot defects  

Science Conference Proceedings (OSTI)

While it is important to exhaustively verify IC designs for their functional performance, it is equally important to verify their robustness against spot defects, that is, to foresee what will happen to the design when it is exposed to defect conditions ...

J. Pineda de Gyvez; C. Di

2006-11-01T23:59:59.000Z

100

Multidimensional Multiphysics Simulation of Nuclear Fuel Behavior  

Science Conference Proceedings (OSTI)

Important aspects of fuel rod behavior, for example pellet-clad mechanical interaction (PCMI), fuel fracture, oxide formation, non- axisymmetric cooling, and response to fuel manufacturing defects, are inherently multidimensional in addition to being complicated multiphysics problems. Many current modeling tools are strictly 2D axisymmetric or even 1.5D. This paper outlines the capabilities of a new fuel modeling tool able to analyze either 2D axisymmetric or fully 3D models. These capabilities include temperature-dependent thermal conductivity of fuel; swelling and densification; fuel creep; pellet fracture; fission gas release; cladding creep; irradiation growth; and gap mechanics (contact and gap heat transfer). The need for multiphysics, multidimensional modeling is then demonstrated through a discussion of results for a set of example problems. The first, a 10-pellet rodlet, demonstrates the viability of the solution method employed. This example highlights the effect of our smeared cracking model and also shows the multidimensional nature of discrete fuel pellet modeling. The second example relies on our multidimensional, multiphysics approach to analyze a missing pellet surface problem. The next example is the analysis of cesium diffusion in a TRISO fuel particle with defects. As a final example, we show a lower-length-scale simulation coupled to a continuum-scale simulation.

R. L. Williamson; J. D. Hales; S. R. Novascone; M. R. Tonks; D. R. Gaston; C. J. Permann; D. Andrs; R. C. Martineau

2012-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

CHARGED POINT DEFECT IN RUTILE TIO2:FROM DEFECT CHARGE DISTRIBUTION TO DEFECT PHONON FREE ENERGY.  

E-Print Network (OSTI)

??The dominant charged point defects in transition metal oxides can change with temperature (T) and oxygen partial pressure (PO2) to control the electrical properties of (more)

Li, Xin

2010-01-01T23:59:59.000Z

102

Positive muon and the positron as probes of defects  

SciTech Connect

The positive muon and the positron are each being used nowadays to investigate defects in condensed matter. A brief summary of the experimental methods employed with each particle is given in this paper. Similarities and differences between the behavior of the two leptons when implanted in consensed matter are pointed out, and by means of a comparison between muon and positron data in Al it is shown that the combination of muon and positron experiments can serve as a useful new probe of defects in solids.

Lynn, K G

1980-01-01T23:59:59.000Z

103

2010 Defects in Semiconductors GRC  

SciTech Connect

Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, as well as an emphasis on the development of novel defect detection methods and first-principles defect theories. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference will deal with point and extended defects in a broad range of electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, oxides, sp{sup 2} carbon based-materials, and photovoltaic/solar cell materials, and in understanding important defect phenomena such as doping bottleneck in nanostructures and the diffusion of defects and impurities. The program consists of about twenty invited talks and a number of contributed poster sessions. The emphasis should be on work which has yet to be published. The large amount of discussion time provides an ideal forum for dealing with topics that are new and/or controversial.

Shengbai Zhang

2011-01-06T23:59:59.000Z

104

Sequential detection of web defects  

DOE Patents (OSTI)

A system for detecting defects on a moving web having a sequential series of identical frames uses an imaging device to form a real-time camera image of a frame and a comparitor to comparing elements of the camera image with corresponding elements of an image of an exemplar frame. The comparitor provides an acceptable indication if the pair of elements are determined to be statistically identical; and a defective indication if the pair of elements are determined to be statistically not identical. If the pair of elements is neither acceptable nor defective, the comparitor recursively compares the element of said exemplar frame with corresponding elements of other frames on said web until one of the acceptable or defective indications occur.

Eichel, Paul H. (Albuquerque, NM); Sleefe, Gerard E. (Cedar Crest, NM); Stalker, K. Terry (Albuquerque, NM); Yee, Amy A. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

105

Compliant mechanism learning toolkit  

E-Print Network (OSTI)

This thesis concerns a toolkit designed to assist in learning the behavior of complaint mechanisms. In the design of complaint mechanisms, increasingly complicated designs behave in ways that are harder to intuitively ...

Allard, Nicholas (Nicholas A.)

2006-01-01T23:59:59.000Z

106

Fatigue Behaviors at Evelated Temperature  

Science Conference Proceedings (OSTI)

Mar 13, 2012... Mechanical Behavior of 5083-H116 and 5456-H116: Mohsen Seifi1; Justin Brosi1; John Lewandowski1; 1Case Western Reserve University

107

CREEP BEHAVIOR AND PHYSICAL AGING INFLUENCE IN ...  

Science Conference Proceedings (OSTI)

CREEP BEHAVIOR AND PHYSICAL AGING INFLUENCE IN PEN FILM. ML Cerrada, GB McKenna. Structure and Mechanics ...

108

Defect Structures and Electronic Properties of Graphene  

Science Conference Proceedings (OSTI)

Defect Structures and Electronic Properties of Graphene. Summary: Graphene and related materials have remarkable physical ...

2013-07-15T23:59:59.000Z

109

Apparatus and method for defect testing of integrated circuits  

DOE Patents (OSTI)

An apparatus and method for defect and failure-mechanism testing of integrated circuits (ICs) is disclosed. The apparatus provides an operating voltage, V.sub.DD, to an IC under test and measures a transient voltage component, V.sub.DDT, signal that is produced in response to switching transients that occur as test vectors are provided as inputs to the IC. The amplitude or time delay of the V.sub.DDT signal can be used to distinguish between defective and defect-free (i.e. known good) ICs. The V.sub.DDT signal is measured with a transient digitizer, a digital oscilloscope, or with an IC tester that is also used to input the test vectors to the IC. The present invention has applications for IC process development, for the testing of ICs during manufacture, and for qualifying ICs for reliability.

Cole, Jr., Edward I. (Albuquerque, NM); Soden, Jerry M. (Placitas, NM)

2000-01-01T23:59:59.000Z

110

Tracking defect warnings across versions  

Science Conference Proceedings (OSTI)

Various static analysis tools will analyze a software artifact in order to identify potential defects, such as misused APIs, race conditions and deadlocks, and security vulnerabilities. For a number of reasons, it is important to be able to track the ... Keywords: FindBugs, Java, bug histories, bug tracking, static analysis

Jaime Spacco; David Hovemeyer; William Pugh

2006-05-01T23:59:59.000Z

111

Causes of Paint Film Defects  

Science Conference Proceedings (OSTI)

Table 9   Common causes of paint film defects...Dip, flow, roller, spray Improper applicator/metering roll speeds Roller Undesirable pattern Swelling of roll Roller Roll improperly ground Roller Foreign material on roll Roller Poor spray gun technique Spray Runs (curtains, sags) Too much solvent Dip, flow, spray Paint surface or drying atmosphere...

112

Evaluation of the thermal-hydraulic response and fuel rod thermal and mechanical deformation behavior during the power burst facility test LOC-3. [PWR  

Science Conference Proceedings (OSTI)

An evaluation of the results from the LOC-3 nuclear blowdown test conducted in the Power Burst Facility is presented. The test objective was to examine fuel and cladding behavior during a postulated cold leg break accident in a pressurized water reactor (PWR). Separate effects of rod internal pressure and the degree of irradiation were investigated in the four-rod test. Extensive cladding deformation (ballooning) and failure occurred during blowdown. The deformation of the low and high pressure rods was similar; however, the previously irradiated test rod deformed to a greater extent than a similar fresh rod exposed to identical system conditions.

Yackle, T.R.; MacDonald, P.E.; Broughton, J.M.

1980-01-01T23:59:59.000Z

113

Inspection of lithographic mask blanks for defects  

DOE Patents (OSTI)

A visible light method for detecting sub-100 nm size defects on mask blanks used for lithography. By using optical heterodyne techniques, detection of the scattered light can be significantly enhanced as compared to standard intensity detection methods. The invention is useful in the inspection of super-polished surfaces for isolated surface defects or particulate contamination and in the inspection of lithographic mask or reticle blanks for surface defects or bulk defects or for surface particulate contamination.

Sommargren, Gary E. (Santa Cruz, CA)

2001-01-01T23:59:59.000Z

114

Second workshop role of point defects/defect complexes in silicon device fabrication  

DOE Green Energy (OSTI)

Abstracts are presented of 24 papers, arranged under the following session/panel headings: defects and impurities in commercial photovoltaic Si substrates, point defects and point defect processes, impurity gettering for Si solar cells, gettering in Si solar cells, and passivation of impurities and defects.

Not Available

1992-01-01T23:59:59.000Z

115

Second workshop role of point defects/defect complexes in silicon device fabrication. Book of abstracts  

DOE Green Energy (OSTI)

Abstracts are presented of 24 papers, arranged under the following session/panel headings: defects and impurities in commercial photovoltaic Si substrates, point defects and point defect processes, impurity gettering for Si solar cells, gettering in Si solar cells, and passivation of impurities and defects.

Not Available

1992-11-01T23:59:59.000Z

116

Atomistic Studies of Defect Cluster Migration mechanisms in UO2  

Science Conference Proceedings (OSTI)

... phase field modeling. This work is supported by the EFRC program funded by DOE BES under Award Number FWP 1356. Proceedings Inclusion? Planned:...

117

Interface Structures, Defects, and Mechanical Properties at fcc-bcc ...  

Science Conference Proceedings (OSTI)

... Cu-Nb composites exhibit high strength and enhanced radiation damage tolerance. ... Modeling of the Mobility of Boundaries of Deformation Twins in Alpha-Iron ... Characterization of Reaction Layers in Mn1.5Co1.5O4 Coated Fuel Cell...

118

Multiscale Modeling of Defect Mechanics in Nuclear Materials  

Science Conference Proceedings (OSTI)

Abstract Scope, The key to developing advanced materials for nuclear applications is ... Physics-Based Homogenization of Random Continuum Microstructures.

119

The Defect Energies and Deformation Mechanisms of Single Crystal Superalloys  

E-Print Network (OSTI)

vitally important in applications which require very high power out- puts from compact power sources, particularly in the aircraft and ship industries. Recently they have also been used industrially for pumping natural gas across continents and for small... continuous induction, compression, combustion and exhaust cycle. The continuous cycle and absence of reciprocating parts gives a smooth running engine which enables higher power outputs to be gained from gas turbines, when compared with piston engines...

Hillier, Graham Stewart

1985-01-29T23:59:59.000Z

120

Reflection and Transmission for Conformal Defects  

E-Print Network (OSTI)

We consider conformal defects joining two conformal field theories along a line. We define two new quantities associated to such defects in terms of expectation values of the stress tensors and we propose them as measures of the reflectivity and transmissivity of the defect. Their properties are investigated and they are computed in a number of examples. We obtain a complete answer for all defects in the Ising model and between certain pairs of minimal models. In the case of two conformal field theories with an enhanced symmetry we restrict ourselves to non-trivial defects that can be obtained by a coset construction.

Thomas Quella; Ingo Runkel; Gerard M. T. Watts

2006-11-27T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Nanomaterials: Mechanics and Mechanisms (2008), by K.T. Ramesh  

Science Conference Proceedings (OSTI)

Mar 10, 2010 ... At nanoscale, matters show distinctly different behaviors from their bulk materials, from mechanical properties to physical and chemical...

122

Superconformal defects in the tricritical Ising model  

E-Print Network (OSTI)

We study superconformal defect lines in the tricritical Ising model in 2 dimensions. By the folding trick, a superconformal defect is mapped to a superconformal boundary of the N=1 superconformal unitary minimal model of c=7/5 with D_6-E_6 modular invariant. It turns out that the complete set of the boundary states of c=7/5 D_6-E_6 model cannot be interpreted as the consistent set of the superconformal defects in the tricritical Ising model since it does not contain the ``no defect'' boundary state. Instead, we find a set of 18 consistent superconformal defects including ``no defect'' and satisfying the Cardy condition. This set also includes some defects which are not purely transmissive or purely reflective.

Gang, Dongmin

2008-01-01T23:59:59.000Z

123

Superconformal defects in the tricritical Ising model  

E-Print Network (OSTI)

We study superconformal defect lines in the tricritical Ising model in 2 dimensions. By the folding trick, a superconformal defect is mapped to a superconformal boundary of the N=1 superconformal unitary minimal model of c=7/5 with D_6-E_6 modular invariant. It turns out that the complete set of the boundary states of c=7/5 D_6-E_6 model cannot be interpreted as the consistent set of superconformal defects in the tricritical Ising model since it does not contain the "no defect" boundary state. Instead, we find a set of 18 consistent superconformal defects including "no defect" and satisfying the Cardy condition. This set also includes some defects which are not purely transmissive or purely reflective.

Dongmin Gang; Satoshi Yamaguchi

2008-09-01T23:59:59.000Z

124

Conformal nets III: fusion of defects  

E-Print Network (OSTI)

Conformal nets provides a mathematical model for conformal field theory. We define a notion of defect between conformal nets, formalizing the idea of an interaction between two conformal field theories. We introduce an operation of fusion of defects, and prove that the fusion of two defects is again a defect, provided the fusion occurs over a conformal net of finite index. There is a notion of sector (or bimodule) between two defects, and operations of horizontal and vertical fusion of such sectors. Our most difficult technical result is that the horizontal fusion of the vacuum sectors of two defects is isomorphic to the vacuum sector of the fused defect. Equipped with this isomorphism, we construct the basic interchange isomorphism between the horizontal fusion of two vertical fusions and the vertical fusion of two horizontal fusions of sectors.

Arthur Bartels; Christopher L. Douglas; Andr Henriques

2013-10-30T23:59:59.000Z

125

Computer code for the atomistic simulation of lattice defects and dynamics. [COMENT code  

Science Conference Proceedings (OSTI)

This document has been prepared to satisfy the need for a detailed, up-to-date description of a computer code that can be used to simulate phenomena on an atomistic level. COMENT was written in FORTRAN IV and COMPASS (CDC assembly language) to solve the classical equations of motion for a large number of atoms interacting according to a given force law, and to perform the desired ancillary analysis of the resulting data. COMENT is a dual-purpose intended to describe static defect configurations as well as the detailed motion of atoms in a crystal lattice. It can be used to simulate the effect of temperature, impurities, and pre-existing defects on radiation-induced defect production mechanisms, defect migration, and defect stability.

Schiffgens, J.O.; Graves, N.J.; Oster, C.A.

1980-04-01T23:59:59.000Z

126

Release of impurities from structural defects in polycrystalline silicon solar cells  

DOE Green Energy (OSTI)

It is critical to understand the behavior of metallic impurities in polycrystalline silicon used for solar cells. These impurities significantly increase the minority carrier recombination rate and, in turn, degrade cell performance. Impurity gettering is a commonly used method to remove these impurities from the material, however, past work has suggested that impurity release from structural defects drastically limits the gettering process. Presently, there is only a limited understanding of impurity release from structural defects. In this work, a correlation between structural defects and the location of metal impurities in as-grown material is established and the release of nickel and copper from structural defects in polycrystalline silicon was studied in as-grown material and after sequential thermal treatments which dissolve the impurities into the silicon matrix. Synchrotron-based x-ray fluorescence impurity mapping with spatial resolution of {approx} 1 {micro}m, was used to determine impurity distributions after each thermal treatment.

McHugo, S.A. [Lawrence Berkeley National Lab., CA (United States). Advanced Light Source; Imaizumi, M. [Toyota Technological Inst., Nagoya (Japan)

1997-04-01T23:59:59.000Z

127

Internal hydriding in irradiated defected Zircaloy fuel rods: A review (LWBR Development Program)  

DOE Green Energy (OSTI)

Although not a problem in recent commercial power reactors, including the Shippingport Light Water Breeder Reactor, internal hydriding of Zircaloy cladding was a persistent cause of gross cladding failures during the 1960s. It occurred in the fuel rods of water-cooled nuclear power reactors that had a small cladding defect. This report summarizes the experimental findings, causes, mechanisms, and methods of minimizing internal hydriding in defected Zircaloy-clad fuel rods. Irradiation test data on the different types of defected fuel rods, intentionally fabricated defected and in-pile operationally defected rods, are compared. Significant factors affecting internal hydriding in defected Zircaloy-clad fuel rods (defect hole size, internal and external sources of hydrogen, Zircaloy cladding surface properties, nickel alloy contamination of Zircaloy, the effect of heat flux and fluence) are discussed. Pertinent in-pile and out-of-pile test results from Bettis and other laboratories are used as a data base in constructing a qualitative model which explains hydrogen generation and distribution in Zircaloy cladding of defected water-cooled reactor fuel rods. Techniques for minimizing internal hydride failures in Zircaloy-clad fuel rods are evaluated.

Clayton, J C

1987-10-01T23:59:59.000Z

128

H Diffusion for Impurity and Defect Passivation: A Physical Model for Solar Cell Processing; Preprint  

DOE Green Energy (OSTI)

We propose a physical model for diffusion of H in Si containing impurities and defects. The diffusion occurs via several parallel mechanisms, involving complex formation (trapping) and dissociation (detrapping) at impurities and defects, hopping in lattice interstitial sites, and charge-state conversion. The role of bulk and process-induced traps is considered to explain observations from plasma, ion implantation, and PECVD-nitridation processes.

Sopori, B. L.; Zhang, Y.; Reedy, R.

2002-05-01T23:59:59.000Z

129

Simulation of the Manufacturing of Non-Crimp Fabric-Reinforced Composite Wind Turbine Blades to Predict the Formation of Wave Defects  

SciTech Connect

NCFs (Non-Crimp Fabrics) are commonly used in the design of wind turbine blades and other complex systems due to their ability to conform to complex shapes without the wrinkling that is typically experienced with woven fabrics or prepreg tapes. In the current research, a form of vacuum assisted resin transfer molding known as SCRIMP registered is used to manufacture wind turbine blades. Often, during the compacting of the fabric layers by the vacuum pressure, several plies may bunch together out-of-plane and form wave defects. When the resin is infused, the areas beneath the waves become resin rich and can compromise the structural integrity of the blade. A reliable simulation tool is valuable to help predict where waves and other defects may appear as a result of the manufacturing process. Forming simulations often focus on the in-plane shearing and tensile behavior of fabrics and do not necessarily consider the bending stiffness of the fabrics, which is important to predict the formation of wrinkles and/or waves. This study incorporates experimentally determined in-plane shearing, tensile, and bending stiffness information of NCFs into a finite element model (ABAQUS/Explicit) of a 9-meter wind turbine blade to investigate the mechanical behaviors that can lead to the formation of waves as a result of the manufacturing process.

Fetfatsidis, K. A.; Sherwood, J. A. [Department of Mechanical Engineering, University of Massachusetts, Lowell One University Ave., Lowell, MA 01854 (United States)

2011-05-04T23:59:59.000Z

130

Migration of positively charged defects in (alpha)-quartz  

SciTech Connect

We apply a newly developed quantum-mechanics/molecular-mechanics (QM/MM) scheme to simulate the migration of charged oxygen defects in {alpha}-quartz. We simulate the transition mechanism and compute the potential energy and free energy surface for the puckering of the symmetric charged oxygen vacancy and the formation of the E{prime}{sub 1} center. By overcoming low energy barriers this puckering mechanism can be reiterated allowing the drift of the positive charge localized on an over-coordinated oxygen atom. This process enhances the stability of the E{prime}{sub 1} center and can be regarded as an important channel of structural reorganization of oxygen deficient silica in the presence of strong polarizing electric fields.

Laino, T; Donadio, D; Kuo, I W

2007-01-30T23:59:59.000Z

131

Improved, Defect-Free Electrode Materials  

The present invention provides simple, cost effective methods for the preparation of lithium iron phosphate material that is defect-free and therefore ...

132

Improved, Defect-Free Electrode Materials - Energy ...  

The present invention provides simple, cost effective methods for the preparation of lithium iron phosphate material that is defect-free and therefore ...

133

Suspect/Counterfeit and Defective Items  

NLE Websites -- All DOE Office Websites (Extended Search)

Items Home SuspectCounterfeit Items Defective Items Safety Advisories Safety Alerts Safety Bulletins SCI Points of Contact SCI Studies References Topical Search SCI-DI...

134

Computational Modeling of Defect Evolution under Irradiation  

Science Conference Proceedings (OSTI)

Mar 14, 2012 ... Radiation Effects in Ceramic Oxide and Novel LWR Fuels: Computational Modeling of Defect Evolution under Irradiation Sponsored by: The...

135

Quantifying Edge Defects in Drilled FRP Composites  

E-Print Network (OSTI)

Drilling of Aramid and Carbon Fiber Polymer Composites,the Exit Defects in Carbon Fiber-Reinforced Plastic Plateswith a High Modulus CFRP (Carbon- Fiber Reinforced Polymer)

Vijayaraghavan, Athulan; Dornfeld, David; Dharan, C. K. Hari

2006-01-01T23:59:59.000Z

136

Structure, Defects, and Scattering in Graphene  

Science Conference Proceedings (OSTI)

Structure, Defects, and Scattering in Graphene. ... (b) STM image of a complex moir pattern observed in multilayer graphene grown on SiC. ...

2013-04-10T23:59:59.000Z

137

International Symposium on Defects, Transport and Related ...  

Science Conference Proceedings (OSTI)

Structure, including point and other defects in crystalline ceramic and amorphous ceramic solids, different types of in-situ and spectroscopic studies (NMR, EPR,...

138

Hydrogen effect on the nanomechanical behavior of amorphous ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2014 TMS Annual Meeting & Exhibition. Symposium , Mechanical Behavior at the Nanoscale II. Presentation Title, Hydrogen effect...

139

Energy levels and decoherence properties of single electron and nuclear spins in a defect center in diamond  

E-Print Network (OSTI)

The coherent behavior of the single electron and single nuclear spins of a defect center in diamond and a 13C nucleus in its vicinity, respectively, are investigated. The energy levels associated with the hyperfine coupling of the electron spin of the defect center to the 13C nuclear spin are analyzed. Methods of magnetic resonance together with optical readout of single defect centers have been applied in order to observe the coherent dynamics of the electron and nuclear spins. Long coherence times, in the order of microseconds for electron spins and tens of microseconds for nuclear spins, recommend the studied system as a good experimental approach for implementing a 2-qubit gate.

I. Popa; T. Gaebel; M. Domhan; C. Wittmann; F. Jelezko; J. Wrachtrup

2004-09-12T23:59:59.000Z

140

The role of point defects and defect complexes in silicon device processing. Summary report and papers  

DOE Green Energy (OSTI)

This report is the summary of the third workshop on the role of point defects and defect complexes in silicon device processing. The workshop was organized: (1) to discuss recent progress in the material quality produced by photovoltaic Si manufacturers, (2) to foster the understanding of point defect issues in Si device processing, (3) to review the effects of inhomogeneities on large- area solar cell performance, (4) to discuss how to improve Si solar cell processing, and (5) to develop a new understanding of gettering, defect passivation, and defect annihilation. Separate abstract were prepared for the individual papers, for the database.

Sopori, B.; Tan, T.Y.

1994-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Exploiting imperfections: Directed assembly of surface colloids via bulk topological defects  

E-Print Network (OSTI)

We exploit the long-ranged elastic fields inherent to confined nematic liquid crystals to assemble colloidal particles trapped at the liquid crystal interface into reconfigurable structures with complex symmetries and packings. Spherical colloids with homeotropic anchoring trapped at the interface between air and the nematic liquid crystal 5CB create quadrupolar distortions in the director field causing particles to repel and consequently form close-packed assemblies with a triangular habit. Here we report on complex, open structures organized via interactions with defects in the bulk. Specifically, by confining the nematic liquid crystal in an array of microposts with homeotropic anchoring conditions, we cause defect rings to form at well-defined locations in the bulk of the sample. These defects source elastic deformations that direct the assembly of the interfacially-trapped colloids into ring-like assemblies, which recapitulate the defect geometry even when the microposts are completely immersed in the nematic. When the surface density of the colloids is high, they form a ring near the defect and a hexagonal lattice far from it. Since topographically complex substrates are easily fabricated and liquid crystal defects are readily reconfigured, this work lays the foundation for a new, robust mechanism to dynamically direct assembly over large areas by controlling surface anchoring and associated bulk defect structure.

Marcello Cavallaro Jr.; Mohamed A. Gharbi; Daniel A. Beller; Simon ?opar; Zheng Shi; Tobias Baumgart; Shu Yang; Randall D. Kamien; Kathleen J. Stebe

2013-08-11T23:59:59.000Z

142

Mechanical Behavior of Biological Materials II  

Science Conference Proceedings (OSTI)

... as it may provide a basis for new synthetic, yet bioinspired, armor materials. ... more mobility and degrees of freedom than traditional rigid ballistic vests.

143

Mechanical Behavior Related to Interface Physics  

Science Conference Proceedings (OSTI)

Jul 31, 2011 ... Interface Bond Strength of HIP-Clad Depleted Uranium and 6061-Aluminum Interface Role in the Shock Response of Cu/Nb Metallic...

144

The Structure and Mechanical Behavior of Ice  

Science Conference Proceedings (OSTI)

This work was supported by the Army Research Office and Office of Naval Research and by Exxon and Mobil. References 1. M.F. Perutz, J. Glaciol., 1 (1948 ), p.

145

Mechanical Behavior of Melt Mixing Polypropylene Organoclay ...  

Science Conference Proceedings (OSTI)

To study the effect of the nanocomposite dispersion and morphology, another nanocomposite was prepared by melt mixing of polypropylene and a modified...

146

Mechanical Behavior of Biological Materials I  

Science Conference Proceedings (OSTI)

Mar 2, 2011 ... The Arapaimas is one of the largest freshwater fish with a length of more than 2m, living in Amazon river. Their armor-like scales with laminate...

147

Mechanical Behavior of Biological Materials II  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Structure and Fracture Resistance of Armored Fish Scales: Wen Yang1; Bernd Gludovatz2; Elizabeth Zimmermann2; Robert Ritchie3; Marc...

148

Mechanical Behavior and Modeling - Programmaster.org  

Science Conference Proceedings (OSTI)

Oct 29, 2013 ... Because of their low density, high temperature strength, and notch insensitivity silicon carbide fiber reinforced silicon carbide ceramic matrix...

149

Mechanical Behavior Related to Interface Physics II  

Science Conference Proceedings (OSTI)

Scope, Future energy technologies demand novel materials that tolerate ... In nanostructured materials, however, they dominate material response and can lead...

150

Processing and Mechanical Behavior of Unalloyed Plutonium  

Science Conference Proceedings (OSTI)

Characterization of Wastes Generated during Stainless Steel Production Charpy Impact Tests in Epoxy ... Differential Characterization of Ikperejere Iron shale and Iron Sandstone Deposit ... High Temperature Exposure of Oil Well Cements.

151

Processing and Mechanical Behavior of Unalloyed Plutonium  

Science Conference Proceedings (OSTI)

Abstract Scope, Unalloyed plutonium presents a wide variety of challenges to the ... AlMnCrCuFeNi Multicomponent Alloy with Superior Hardness and Corrosion...

152

Mechanical Behavior at the Nanoscale II  

Science Conference Proceedings (OSTI)

Jul 15, 2013... tension-tension loading of micron-sized Cu lines at temperatures up to 673 K ... Room Temperature In Situ Transmission Electron Microscopy...

153

Mechanical Behavior of Polyester Matrix Composites Reinforced ...  

Science Conference Proceedings (OSTI)

Conference Tools for 2010 TMS Annual Meeting & Exhibition ... A possible solution for both, the dimensional limitation and weather deterioration is to separate...

154

The Microstructure and Mechanical Behavior of Fe  

Science Conference Proceedings (OSTI)

Research supported by DOE Award #DE-FG02-07ER46392; the ORNL ... Early- stage formation of Copper nanoclusters in model reactor pressure vessel steel.

155

Mechanical Behavior of Natural Sisal Fibers  

Science Conference Proceedings (OSTI)

Piezoelectric Smart Composites: Electromechanical Properties and Design Maps Preparation of ... Research on Aluminum Foam Railway Noise Barrier.

156

Weldability and Mechanical Behavior of GTD-141  

Science Conference Proceedings (OSTI)

Superalloys 2004. Edited by K.A. Green, ... TMS (The Minerals, Metals & Materials Society), 2004 ..... J. H. Wood, D. A. Shores and N. R. Lindblad, US Patent.

157

Dinosaur behavior  

NLE Websites -- All DOE Office Websites (Extended Search)

Dinosaur behavior Dinosaur behavior Name: kevv Status: N/A Age: N/A Location: N/A Country: N/A Date: Around 1993 Question: Did the movie Jurassic Park accurately reflect the known behavior of dinosaurs? Replies: Well, since we do not have an accurate record of that time period (Man showed up about ten million years after T-rex thundered across the plains of Antarctica *grin*) so we cannot say for certain WHAT the dinosaurs did. However, since they were wild animals, we can extrapolate from their modern contemporaries and from our knowledge of their individual anatomies what kind of behaviors they exhibited. A predator with large claws probably hunts by slashing and by piercing and holding on to prey. An herbivore with large spikes growing on its tail probably used them to fend off attackers like a spiked club -- I do not think it was much of a fashion statement

158

Interactive Session A: Mechanisms/Models for Mechanical Behavior  

Science Conference Proceedings (OSTI)

Sep 10, 2012... Milling Tests: Ralf Webler1; Markus Krottenthaler1; Steffen Neumeier1; Karsten Durst1; Mathias Gken1; 1University Erlangen-Nuremberg

159

Photoluminescence in Chemical Vapor Deposited ZnS: insight into electronic defects  

SciTech Connect

Photoluminescence spectra taken from chemical vapor deposited (CVD) ZnS are shown to exhibit sub-band-gap emission bands characteristic of isoelectronic oxygen defects. The emission spectra vary spatially with position and orientation with respect to the major axis of CVD growth. These data suggest that a complex set of defects exist in the band gap of CVD ZnS whose structural nature is highly dependent upon local deposition and growth conditions, contributing to inherent heterogeneity in optical behavior throughout the material.

McCloy, John S.; Potter, B.g.

2013-08-09T23:59:59.000Z

160

Defect aggregation kinetics in calcium fluoride  

Science Conference Proceedings (OSTI)

Defects in solid materials are responsible for many of their most interesting and critical properties. The authors have developed a site-selective laser technique that allows us to monitor the aggregation of rare earth ion defects in solids on the microscopic scale. This excitation absorption laser method enables us to derive kinetic rate information and thermodynamic parameters for the distribution of defects in solids. For doped materials, various types of defects arise when the dopant ions have ionic charges that differ from the charges of host crystal ions. In model systems such as alkaline earth fluorides doped with trivalent rare earth ions, some defect sites consist of a single dopant ion, while others consist of clusters of dopant cations and interstitial anions. Heat treatment of doped samples leads to a distribution of the various types of defect sites that is characteristic of the temperature and length of heat treatment and the total dopant ion concentration. The results from a study of the formation of trivalent europium ion defect aggregates in calcium fluoride indicate that our method successfully monitors changes in individual site concentrations resulting from heat treatment. The results of this study are consistent with the formation of negatively charged dimer and trimer defects in Eu{sup 3+}:CaF{sub 2} crystals from isolated europium ion and (Eu:F{sub i}) single pair defects. In addition, he presents evidence for rapid equilibrium between the isolated ion and the single pair. Other work presented in this thesis includes the development of a high-temperature fluorine oxidation apparatus that was used to convert divalent europium ions to the trivalent state in calcium fluoride single crystals. This apparatus was also used to increase the superconducting {Tc}'s of YBa{sub 2}Cu{sub 3}O{sub 7-x} through modification of copper-oxygen oxidation states.

Cirillo, K.M.

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Polymers in anisotropic environment with extended defects  

E-Print Network (OSTI)

The conformational properties of flexible polymers in d dimensions in environments with extended defects are analyzed both analytically and numerically. We consider the case, when structural defects are correlated in \\varepsilon_d dimensions and randomly distributed in the remaining d-\\varepsilon_d. Within the lattice model of self-avoiding random walks (SAW), we apply the pruned enriched Rosenbluth method (PERM) and find the estimates for scaling exponents and universal shape parameters of polymers in environment with parallel rod-like defects (\\varepsilon_d=1). An analytical description of the model is developed within the des Cloizeaux direct polymer renormalization scheme.

V. Blavatska; K. Haydukivska

2012-12-17T23:59:59.000Z

162

Exploration of Quench Initiation Due to Intentional Geometrical Defects in a High Magnetic Field Region of an SRF Cavity  

SciTech Connect

A computer program which was used to simulate and analyze the thermal behaviors of SRF cavities has been developed at Jefferson Lab using C++ code. This code was also used to verify the quench initiation due to geometrical defects in high magnetic field region of SRF cavities. We built a CEBAF single cell cavity with 4 artificial defects near equator, and this cavity has been tested with T-mapping. The preheating behavior and quench initiation analysis of this cavity will be presented here using the computer program.

J. Dai, K. Zhao, G.V. Eremeev, R.L. Geng, A.D. Palczewski; Dai, J. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Palczewski, A. D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Eremeev, G. V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Geng, R. L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhao, K. [Institute of Heavy Ion Physics, Peking University, Beijing (China)

2011-07-01T23:59:59.000Z

163

3.225 Electronic and Mechanical Properties of Materials, Summer 2002  

E-Print Network (OSTI)

Electrical, optical, magnetic, and mechanical properties of metals, semiconductors, ceramics and polymers. Discussion of roles of bonding, structure (crystalline, defect, energy band and microstructure) and composition in ...

Gibson, Lorna J.

2002-01-01T23:59:59.000Z

164

International Symposium on Defects, Transport and Related ...  

Science Conference Proceedings (OSTI)

Structure, including point and other defects in crystalline ceramic and ... Compositional Stability and Oxygen Exchange Kinetics of Oxide Hetero-Junction Electrodes ... Secondary Transport Phenomena in Ceramic Membranes under...

165

Generalized quantum defect methods in quantum chemistry  

E-Print Network (OSTI)

The reaction matrix of multichannel quantum defect theory, K, gives a complete picture of the electronic structure and the electron - nuclear dynamics for a molecule. The reaction matrix can be used to examine both bound ...

Altunata, Serhan

2006-01-01T23:59:59.000Z

166

Investigating Extreme Ultraviolet Lithography Mask Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

types of mask defects recorded in several state-of-the-art tools: the AIT, a scanning electron microscope (SEM), and a commercial deep ultraviolet (DUV) mask inspection tool....

167

Investigating Extreme Ultraviolet Lithography Mask Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

La Fontaine, A. Tchikoulaeva, and C. Holfeld, "Actinic imaging of native and programmed defects on a full-field mask," Proc. SPIE 7636, 76361A (2010). ALS Science Highlight 213...

168

Investigating Extreme Ultraviolet Lithography Mask Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Tchikoulaeva, and C. Holfeld, "Actinic imaging of native and programmed defects on a full-field mask," Proc. SPIE 7636, 76361A (2010). ALS Science Highlight 213 ALSNews Vol. 311...

169

Supersymmetric K field theories and defect structures  

E-Print Network (OSTI)

We construct supersymmetric K field theories (i.e., theories with a non-standard kinetic term) in 1+1 and 2+1 dimensions such that the bosonic sector just consists of a nonstandard kinetic term plus a potential. Further, we study the possibility of topological defect formation in these supersymmetric models. Finally, we consider more general supersymmetric K field theories where, again, topological defects exist in some cases.

Adam, C; Sanchez-Guillen, J; Wereszczynski, A

2011-01-01T23:59:59.000Z

170

Defects in metal crystals. Progress report, May 1, 1979-April 30, 1980  

DOE Green Energy (OSTI)

A broad investigation of the properties of crystal defects in metals and semiconductors was made. Attention during the past year has focused on fundamental properties of point defects (vacancies and self-interstitial atoms); aggregates of point defects (i.e., depleted zones); the range profiles of low-energy (< 1000 eV) implanted /sup 4/He and /sup 1/H in tungsten, the diffusive properties of /sup 4/He and /sup 1/H; the adsorption kinetics and sticking coefficient of hydrogen on tungsten; the imaging of silicon by field-ion microscopy; the chemical analysis of ordered Ni/sub 4/Mo and GaAs - on an atomic scale - via atom-probe field microscopy; and the low-temperature isochronal recovery behavior of ion-irradiated Ni/sub 4/Mo and Pt/sub 3/Co. Heavy use was made of the high-resolution field-ion microscope and the atom-probe field-ion microscope.

Seidman, D.N.

1980-01-01T23:59:59.000Z

171

Two-dimensional defect modes in optically induced photonic lattices  

Science Conference Proceedings (OSTI)

In this article, localized linear defect modes due to band gap guidance in two-dimensional photonic lattices with localized or nonlocalized defects are investigated theoretically. First, when the defect is localized and weak, eigenvalues of defect modes bifurcated from edges of Bloch bands are derived analytically. It is shown that in an attractive (repulsive) defect, defect modes bifurcate out from Bloch-band edges with normal (anomalous) diffraction coefficients. Furthermore, distances between defect-mode eigenvalues and Bloch-band edges decrease exponentially with the defect strength, which is very different from the one-dimensional case where such distances decrease quadratically with the defect strength. It is also found that some defect-mode branches bifurcate not from Bloch-band edges, but from quasiedge points within Bloch bands, which is very unusual. Second, when the defect is localized but strong, defect modes are determined numerically. It is shown that both the repulsive and attractive defects can support various types of defect modes such as fundamental, dipole, quadrupole, and vortex modes. These modes reside in various band gaps of the photonic lattice. As the defect strength increases, defect modes move from lower band gaps to higher ones when the defect is repulsive, but remain within each band gap when the defect is attractive, similar to the one-dimensional case. The same phenomena are observed when the defect is held fixed while the applied dc field (which controls the lattice potential) increases. Lastly, if the defect is nonlocalized (i.e., it persists at large distances in the lattice), it is shown that defect modes can be embedded inside the continuous spectrum, and they can bifurcate out from edges of the continuous spectrum algebraically rather than exponentially.

Wang Jiandong; Yang Jianke; Chen Zhigang [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401 (United States); Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States)

2007-07-15T23:59:59.000Z

172

Automated laser scatter detection of surface and subsurface defects in Si{sub 3}N{sub 4} components  

Science Conference Proceedings (OSTI)

Silicon Nitride (Si{sub 3}N{sub 4}) ceramics are currently a primary material of choice to replace conventional materials in many structural applications because of their oxidation resistance and desirable mechanical and thermal properties at elevated temperatures. However, surface or near-subsurface defects, such as cracks, voids, or inclusions, significantly affect component lifetimes. These defects are currently difficult to detect, so a technique is desired for the rapid automated detection and quantification of both surface and subsurface defects. To address this issue, the authors have developed an automated system based on the detection of scattered laser light which provides a 2-D map of surface or subsurface defects. This system has been used for the analysis of flexure bars and button-head tensile rods of several Si{sub 3}N{sub 4} materials. Mechanical properties of these bars have also been determined and compared with the laser scatter results.

Steckenrider, J.S. [Argonne National Lab., IL (United States). Energy Technology Div.

1995-06-01T23:59:59.000Z

173

Pattern formation from defect chaosa theory of chevrons  

Science Conference Proceedings (OSTI)

Keywords: Turing patterns, coupled amplitude equations, defect chaos, electronconvection in liquid crystals

A. G. Rossberg; L. Kramer

1998-04-01T23:59:59.000Z

174

Modeling and Experimental Validation of Multiscale Mechanical ...  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... Jonathan Zimmerman, Sandia National Laboratories. Scope, The mechanical behavior of a material has a strong and complex connection to its...

175

Role of point defects/defect complexes in silicon device processing. Book of abstracts, fourth workshop  

DOE Green Energy (OSTI)

The 41 abstracts are arranged into 6 sessions: impurities and defects in commercial substrates: their sources, effects on material yield, and material quality; impurity gettering in silicon: limits and manufacturability of impurity gettering and in silicon solar cells; impurity/defect passivation; new concepts in silicon growth: improved initial quality and thin films; and silicon solar cell design opportunities.

Not Available

1994-06-01T23:59:59.000Z

176

Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects  

E-Print Network (OSTI)

1 Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects Jared W. Nelson The Blade Reliability Collaborative has been formed to perform comprehensive studies to improve wind turbine uni-directional wind turbine fiber-reinforced composite material with an epoxy resin were utilized

177

Extended Defects in Cdznte Radiation Detectors  

Science Conference Proceedings (OSTI)

Large-volume CdZnTe (CZT) single crystals with electron lifetime exceeding 10 mus have recently become commercially available. This opened the opportunity for making room temperature CZT gamma-ray detectors with extended thicknesses and larger effective areas. However, the extended defects that are present even in the highest-quality material remain a major drawback which affects the availability and cost of large CZT detectors. In contrast to the point defects that control electron lifetime and whose effects on the charge collection can be electronically corrected, the extended defects introduce significant fluctuations in the collected charge, which increase with a crystal's thickness. The extended defects limit the uniformity in the electrons' drift distance in CZT crystals, above which electron trapping cannot effectively be corrected. In this paper, we illustrate the roles of the extended defects in CZT detectors with different geometries. We emphasize that the crystallinity of commercial CZT materials remains a major obstacle on the path to developing thick, large-volume CZT detectors for gamma-ray imaging and spectroscopy.

Bolotnikov, A.; Babalola, S; Camarda, G; Chen, H; Awadalla, S; Cui, Y; Egarievwe, S; Fochuk, P; Hawrami, R; et. al.

2009-01-01T23:59:59.000Z

178

Measurement of oxygen disorder and nano-twin microstructure associated with columnar defects in YBCO.  

Science Conference Proceedings (OSTI)

Studies of defects generated by high energy (>1 GeV) heavy ion irradiation in high-Tc superconductors have been performed by transmission electron microscopy (TEM). Our study shows that high dose irradiation leads to the formation of nano-twins, by which the columnar defects are connected. An analysis of the local Fourier components of the image intensity in [001] lattice images indicates that these new ''twin'' boundaries are much more diffuse than pre-existing twin boundaries in YBCO. The mechanism of the formation of nano-twin boundaries on {l_brace}110{r_brace} planes and their possible relation to superconducting properties are discussed.

Yan, Y,

1998-12-18T23:59:59.000Z

179

GaN: Defect and Device Issues  

SciTech Connect

The role of extended and point defects, and key impurities such as C, O and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

Pearton, S.J.; Ren, F.; Shul, R.J.; Zolper, J.C.

1998-11-09T23:59:59.000Z

180

Comment on the article ``UCN anomalous losses and the UCN capture cross section on material defects'' by A. Serebrov et al  

E-Print Network (OSTI)

We present correct solution of the problem about a scattering of the neutron on a point-like defect existing in a medium and show that this mechanism cannot explain anomalous losses of UCN in storage bottles.

A. L. Barabanov; K. V. Protasov

2005-07-08T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Gauge turbulence, topological defect dynamics, and condensation in Higgs models  

E-Print Network (OSTI)

The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appear in the gauge field which are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signalled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang-Mills fields and potential mechanisms how confinement and condensation in non-abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.

Thomas Gasenzer; Larry McLerran; Jan M. Pawlowski; Dnes Sexty

2013-07-19T23:59:59.000Z

182

Fuzzy Logic Connectivity in Semiconductor Defect Clustering  

Science Conference Proceedings (OSTI)

In joining defects on semiconductor wafer maps into clusters, it is common for defects caused by different sources to overlap. Simple morphological image processing tends to either join too many unrelated defects together or not enough together. Expert semiconductor fabrication engineers have demonstrated that they can easily group clusters of defects from a common manufacturing problem source into a single signature. Capturing this thought process is ideally suited for fuzzy logic. A system of rules was developed to join disconnected clusters based on properties such as elongation, orientation, and distance. The clusters are evaluated on a pair-wise basis using the fuzzy rules and are joined or not joined based on a defuzzification and threshold. The system continuously re-evaluates the clusters under consideration as their fuzzy memberships change with each joining action. The fuzzy membership functions for each pair-wise feature, the techniques used to measure the features, and methods for improving the speed of the system are all developed. Examples of the process are shown using real-world semiconductor wafer maps obtained from chip manufacturers. The algorithm is utilized in the Spatial Signature Analyzer (SSA) software, a joint development project between Oak Ridge National Lab (ORNL) and SEMATECH.

Gleason, S.S.; Kamowski, T.P.; Tobin, K.W.

1999-01-24T23:59:59.000Z

183

Design and defect tolerance beyond CMOS  

Science Conference Proceedings (OSTI)

It is well recognized that novel computational models, devices and technologies are needed in order to sustain the remarkable advancement of CMOS-based VLSI circuits and systems. Regardless of the models, devices and technologies, any enhancement/replacement ... Keywords: cmol, defect tolerance, nanotechnology, qca, spin wave

Xiaobo Sharon Hu; Alexander Khitun; Konstantin K. Likharev; Michael T. Niemier; Mingqiang Bao; Kang Wang

2008-10-01T23:59:59.000Z

184

Defect-free ultrahigh flux asymmetric membranes  

DOE Patents (OSTI)

Defect-free, ultrahigh flux integrally-skinned asymmetric membranes having extremely thin surface layers (<0.2 .mu.m) comprised of glassy polymers are disclosed. The membranes are formed by casting an appropriate drope followed by forced convective evaporation of solvent to obtain a dry phase separated asymmetrical structure. The structure is then washed in a precipitation liquid and dried.

Pinnau, Ingo (Austin, TX); Koros, William J. (Austin, TX)

1990-01-01T23:59:59.000Z

185

Bohmian Mechanics  

E-Print Network (OSTI)

Bohmian mechanics is a theory about point particles moving along trajectories. It has the property that in a world governed by Bohmian mechanics, observers see the same statistics for experimental results as predicted by quantum mechanics. Bohmian mechanics thus provides an explanation of quantum mechanics. Moreover, the Bohmian trajectories are defined in a non-conspiratorial way by a few simple laws.

Detlef Duerr; Sheldon Goldstein; Roderich Tumulka; Nino Zanghi

2009-03-15T23:59:59.000Z

186

Mechanical down jar mechanism  

SciTech Connect

This paper describes a mechanical down jar mechanism for freeing stuck objects within a well bore and for conducting other down hole activities. It comprises: an elongate tubular housing having anvil means; mandrel means adapted for connection to an object to be moved downwardly within the well bore and being disposed in telescoping relation with the anvil means and the elongate tubular housing, the mandrel means adapted to be struck by the anvil means to impart a downwardly directed jarring force to the object; the elongate tubular housing having internal firing and recocking detent groove means located in axially spaced relation and forming a firing lug support land therebetween; a radially expandable and retractable firing lug assembly being disposed within the elongate tubular housing and in absence of force being applied axially thereto being radially restrained by the firing lug support land; load spring means being disposed within the elongate tubular housing and being in downward force transmitting relation with the firing lug assembly; recocking spring means being disposed within the elongate tubular housing and having upward axial force transmitting relation with the firing lug assembly.

Taylor, W.T.

1991-12-03T23:59:59.000Z

187

PERSPECTIVE Quantum Mechanics of Black Holes  

E-Print Network (OSTI)

PERSPECTIVE Quantum Mechanics of Black Holes Edward Witten The popular conception of black holes reflects the behavior of the massive black holes found by astronomers and described by classical general to understand the behavior of black holes from a quantum mechanical point of view, however, have arrived

188

Fatigue and Fatigue Crack Propagation Behaviors of High ...  

Science Conference Proceedings (OSTI)

The S-N fatigue and fatigue crack propagation (FCP) behaviors of high ... The mechanisms associated with the improved fatigue resistance for the high...

189

Session AA: Oxide Defects, Localized States, and Nanostructures  

Science Conference Proceedings (OSTI)

Jun 24, 2010 ... 1:30 PM AA1, Vacancy Defect and Defect Cluster Energetics in ... to correlate the commonly observed 1.9-2.1 eV red and 2.3-2.5 eV green...

190

Controlling Defect Density in Polymer-Fullerene Bulk Heterojunction ...  

Science Conference Proceedings (OSTI)

Controlling Defect Density in Polymer-Fullerene Bulk Heterojunction Solar Cells by Optimizing ... Engineering Carbon Nanomaterials for Energy Application.

191

Thermodynamic Control of Stoichiometry-Induced Defects in ...  

Thermodynamic Control of Stoichiometry-Induced Defects in Photovoltaic Materials Note: The technology described above is an early stage opportunity.

192

Enhanced Lattice Defect Formation Associated with Hydrogen and ...  

Science Conference Proceedings (OSTI)

Presentation Title, Enhanced Lattice Defect Formation Associated with Hydrogen and Hydrogen Embrittlement under Elastic Stress of High-Strength Steel.

193

Impurities and defects in photovoltaic Si devices: A review  

DOE Green Energy (OSTI)

The performance of commercial photovoltaic Si devices is strongly controlled by the impurities and defects present in the substrates. A well-designed solar cell processing sequence can mitigate their effects to yield high efficiency devices. Such a process-design requires a comprehensive knowledge of the properties of defects, impurities, and impurity-defect interactions that can occur during device processing. This paper reviews the recent understanding of the impurity and defect issues in Si-photovoltaics.

Sopori, B.

1999-11-04T23:59:59.000Z

194

Cavity Cooling of a Mechanical Resonator in Amorphous Systems  

E-Print Network (OSTI)

Cavity cooling via quantum back-action force can extract thermal fluctuations from a mechanical resonator to reach the quantum ground state. The two-level system (TLS) defects in the surface of a mechanical resonator couple to the mechanical mode via deformation potential and can affect the cooling process significantly. Here, we develop a theory to study the cavity cooling of a mechanical mode in the presence of a TLS defect using the adiabatic elimination technique. Our result shows that the cooling process depends strongly on the resonance and damping rate of the TLS.

Tian, L

2010-01-01T23:59:59.000Z

195

Metrics of Risk Associated with Defects Rediscovery  

E-Print Network (OSTI)

Software defects rediscovered by a large number of customers affect various stakeholders and may: 1) hint at gaps in a software manufacturer's Quality Assurance (QA) processes, 2) lead to an over-load of a software manufacturer's support and maintenance teams, and 3) consume customers' resources, leading to a loss of reputation and a decrease in sales. Quantifying risk associated with the rediscovery of defects can help all of these stake-holders. In this chapter we present a set of metrics needed to quantify the risks. The metrics are designed to help: 1) the QA team to assess their processes; 2) the support and maintenance teams to allocate their resources; and 3) the customers to assess the risk associated with using the software product. The paper includes a validation case study which applies the risk metrics to industrial data. To calculate the metrics we use mathematical instruments like the heavy-tailed Kappa distribution and the G/M/k queuing model.

Miranskyy, Andriy V; Reesor, Mark

2011-01-01T23:59:59.000Z

196

Point defects in silicon crystals studied via complexes with hydrogen  

Science Conference Proceedings (OSTI)

We studied the properties of irradiation-induced point defects and thermal equilibrium vacancies in Si by detecting hydrogen interacting with these point defects. First, we show the irradiation temperature dependence of the point defect concentration. ... Keywords: Frenkel pairs, hydrogen, migration energy, self-interstitials, silicon, vacancies

M. Suezawa; N. Fukata; Y. Takada; R. Taniguchi; F. Hori; R. Oshima

2003-05-01T23:59:59.000Z

197

Investigating Extreme Ultraviolet Lithography Mask Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigating Extreme Ultraviolet Lithography Mask Defects Print Investigating Extreme Ultraviolet Lithography Mask Defects Print Since the 1970s, the semiconductor industry has strived to shrink the cost and size of circuit patterns printed onto computer chips in accordance with Moore's law, doubling the number of transistors on a computer's central processing unit (CPU) every two years. The introduction of extreme ultraviolet (EUV) lithography, printing chips using 13-nm-wavelength light, opens the way to future generations of smaller, faster, and cheaper semiconductors. EUV lithography relies on specialized lenses made of curved mirrors with reflective coatings called multilayers to print patterns with high resolution. One special flat mirror called a mask is particularly sensitive to even the smallest imperfections. To better detect and characterize mask defects, scientists at Berkeley Lab worked with SEMATECH, an international semiconductor industry consortium, to create a unique Fresnel zone-plate microscope on Advanced Light Source Beamline 11.3.2 called the SEMATECH Berkeley Actinic Inspection Tool (AIT).

198

Investigating Extreme Ultraviolet Lithography Mask Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigating Extreme Investigating Extreme Ultraviolet Lithography Mask Defects Investigating Extreme Ultraviolet Lithography Mask Defects Print Wednesday, 28 July 2010 00:00 Since the 1970s, the semiconductor industry has strived to shrink the cost and size of circuit patterns printed onto computer chips in accordance with Moore's law, doubling the number of transistors on a computer's central processing unit (CPU) every two years. The introduction of extreme ultraviolet (EUV) lithography, printing chips using 13-nm-wavelength light, opens the way to future generations of smaller, faster, and cheaper semiconductors. EUV lithography relies on specialized lenses made of curved mirrors with reflective coatings called multilayers to print patterns with high resolution. One special flat mirror called a mask is particularly sensitive to even the smallest imperfections. To better detect and characterize mask defects, scientists at Berkeley Lab worked with SEMATECH, an international semiconductor industry consortium, to create a unique Fresnel zone-plate microscope on Advanced Light Source Beamline 11.3.2 called the SEMATECH Berkeley Actinic Inspection Tool (AIT).

199

Investigating Extreme Ultraviolet Lithography Mask Defects  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigating Extreme Ultraviolet Lithography Mask Defects Print Investigating Extreme Ultraviolet Lithography Mask Defects Print Since the 1970s, the semiconductor industry has strived to shrink the cost and size of circuit patterns printed onto computer chips in accordance with Moore's law, doubling the number of transistors on a computer's central processing unit (CPU) every two years. The introduction of extreme ultraviolet (EUV) lithography, printing chips using 13-nm-wavelength light, opens the way to future generations of smaller, faster, and cheaper semiconductors. EUV lithography relies on specialized lenses made of curved mirrors with reflective coatings called multilayers to print patterns with high resolution. One special flat mirror called a mask is particularly sensitive to even the smallest imperfections. To better detect and characterize mask defects, scientists at Berkeley Lab worked with SEMATECH, an international semiconductor industry consortium, to create a unique Fresnel zone-plate microscope on Advanced Light Source Beamline 11.3.2 called the SEMATECH Berkeley Actinic Inspection Tool (AIT).

200

Defect structure of web silicon ribbon  

DOE Green Energy (OSTI)

Web silicon ribbon has recently emerged as a material for the production of high efficiency solar cells. Since defects introduced during growth may influence locally minority carrier recombination rates, there is now a need to examine the defect structure in detail and to correlate it with electrical activity. This work describes initial observations made on web material by EBIC and HVEM. Although EBIC investigations have shown that dislocations emerging at the web surface enhance minority carrier recombination rates, their density is low enough (typically 10/sup 5/cm/sup -2/) to have only a small effect on the efficiency of the material as a solar cell. Since a condition for dendritic web growth is that the dendrites contain at least two twin boundaries it is usual to find that some of these boundaries extend into the web. These boundaries are formed parallel to the (111) growth surface and are found to be sites of strong electrical activity. HVEM has been used to study the defect structure at the twin boundary. Two types of dislocation networks lying on different (111) planes have been observed, presumably corresponding to two adjacent twin boundaries.

Cunningham, B.; Strunk, H.; Ast, D.

1980-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Simulation of 7050 Wrought Aluminum Alloy Wheel Die Forging and its Defects Analysis based on DEFORM  

Science Conference Proceedings (OSTI)

Defects such as folding, intercrystalline cracking and flow lines outcrop are very likely to occur in the forging of aluminum alloy. Moreover, it is difficult to achieve the optimal set of process parameters just by trial and error within an industrial environment. In producing 7050 wrought aluminum alloy wheel, a rigid-plastic finite element method (FEM) analysis has been performed to optimize die forging process. Processing parameters were analyzed, focusing on the effects of punch speed, friction factor and temperature. Meanwhile, mechanism as well as the evolution with respect to the defects of the wrought wheel was studied in details. From an analysis of the results, isothermal die forging was proposed for producing 7050 aluminum alloy wheel with good mechanical properties. Finally, verification experiment was carried out on hydropress.

Huang Shiquan; Yi Youping; Zhang Yuxun [School of Mechanical and Electrical Engineering, Central South University, Changsha 410083 (China)

2010-06-15T23:59:59.000Z

202

Understanding the Irradiation Behavior of Zirconium Carbide  

SciTech Connect

Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known about basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC- based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response (ZrC) by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation-induced microstructures mapped spatially and temporally, microstructural evolution during post-irradiation annealing, and atomistic modeling of defect formation and transport energetics will provide new, critical understanding about property changes in ZrC. The behavior of materials under irradiation is determined by the balance between damage production, defect clustering, and lattice response. In order to predict those effects at high temperatures so targeted testing can be expanded and extrapolated beyond the known database, it is necessary to determine the defect energetics and mobilities as these control damage accumulation and annealing. In particular, low-temperature irradiations are invaluable for determining the regions of defect mobility. Computer simulation techniques are particularly useful for identifying basic defect properties, especially if closely coupled with a well-constructed and complete experimental database. The close coupling of calculation and experiment in this project will provide mutual benchmarking and allow us to glean a deeper understanding of the irradiation response of ZrC, which can then be applied to the prediction of its behavior in reactor conditions.

Motta, Arthur; Sridharan, Kumar; Morgan, Dane; Szlufarska, Izabela

2013-10-11T23:59:59.000Z

203

Optical Soliton Propagation in a Free-Standing Nonlinear Graphene Monolayer with Defects  

E-Print Network (OSTI)

Recently, optical soliton propagation in an intrinsic nonlinear graphene monolayer configuration has been discovered. However, optical soliton behavior in a free-standing graphene monolayer with defects has not yet been studied. The objective of this article is to employ the generalized finite- difference time-domain (G-FDTD) method to efficiently simulate bright optical solitons, illustrating propagation of the electric field distribution in a free-standing nonlinear layer with variation in nonlinearity along its width. These variations of nonlinearity along the width represent graphene impurities, or defects. Results show that solitons propagate effectively even in the presence of strong spatial variations in the nonlinearity, implying the robustness of the medium with respect to optical propagation.

Frederick Ira Moxley III; Tim Byrnes; Adarsh Radadia; Weizhong Dai

2013-11-22T23:59:59.000Z

204

Bohmian mechanics contradicts quantum mechanics  

E-Print Network (OSTI)

Bohmian mechanics contradicts quantum mechanics Arnold Neumaier Institut fur Mathematik, Universit://solon.cma.univie.ac.at/#24;neum/ Abstract. It is shown that, for a harmonic oscillator in the ground state, Bohmian mechanics and quantum mechanics predict values of opposite sign for certain time correlations. The discrepancy can

Neumaier, Arnold

205

Testing quantum mechanics  

E-Print Network (OSTI)

As experiments continue to push the quantum-classical boundary to include increasingly complex dynamical systems, the interpretation of experimental data becomes more and more challenging: when the observations are noisy, indirect, and limited, how can we be sure that we are observing quantum behavior? This tutorial highlights some of the difficulties in such experimental tests of quantum mechanics, using optomechanics as the central example, and discusses how the issues can be resolved using techniques from statistics and insights from quantum information theory.

Mankei Tsang

2013-06-12T23:59:59.000Z

206

The effect of native point defect thermodynamics on off-stoichiometry in beta-Mg17Al12  

Science Conference Proceedings (OSTI)

The mechanical strength of Mg-Al-Zn alloys can be affected by a fine spatial dispersion of {beta}-Mg{sub 17}Al{sub 12} precipitates in the Mg matrix. In an effort to understand the phase stability and the unusual asymmetric off-stoichiometry observed in {beta}-Mg{sub 17}Al{sub 12}, we have performed a series of first-principles density functional theory (DFT) calculations of bulk and defect properties of Mg{sub 17}Al{sub 12}. Specifically, we consider native point defects (i.e. vacancies and anti-sites) in all four sublattices of Mg{sub 17}Al{sub 12}, i.e. 2a, 8c, 24g (Mg) and 24g (Al). The T = 0 K static energies of defect Mg{sub 17}Al{sub 12} supercells indicate that anti-site defects are energetically favored over vacancies, and the lowest anti-site defect formation energies are in 24g sites for both Al{sub Mg} and Mg{sub Al}. These Al-rich and Mg-rich anti-site defect formation energies are similar in magnitude, and thus do not explain the asymmetric off-stoichiometry of Mg{sub 17}Al{sub 12}. We also investigate the effect of atomic vibrations via DFT phonon calculations on native point defect free energies of Mg{sub 17}Al{sub 12} and combine these entropic contributions with the point defect formation energies to evaluate the thermodynamics of off-stoichiometry in this phase. We find that the formation of the Al{sub Mg} anti-site is not strongly stabilized by vibrational entropy. Thus, we conclude that the observed asymmetry in the off-stoichiometry of the {beta}-Mg{sub 17}Al{sub 12} phase in the Mg-Al phase diagram is not explained by simple native point defect thermodynamics, and must involve a more complicated defect formation mechanism, such as multi-defect clustering.

Wolverton, Christopher [Northwestern University, Evanston

2012-01-01T23:59:59.000Z

207

The role of point defects and defect complexes in silicon device processing. Summary report and papers  

DOE Green Energy (OSTI)

This report is a summary of a workshop hold on August 24--26, 1992. Session 1 of the conference discussed characteristics of various commercial photovoltaic silicon substrates, the nature of impurities and defects in them, and how they are related to the material growth. Session 2 on point defects reviewed the capabilities of theoretical approaches to determine equilibrium structure of defects in the silicon lattice arising from transitional metal impurities and hydrogen. Session 3 was devoted to a discussion of the surface photovoltaic method for characterizing bulk wafer lifetimes, and to detailed studies on the effectiveness of various gettering operations on reducing the deleterious effects of transition metals. Papers presented at the conference are also included in this summary report.

Sopori, B.; Tan, T.Y.

1994-08-01T23:59:59.000Z

208

Argonne CNM Highlight: Mechanical energy dissipation in  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanical Energy Dissipation in Ultrananocrystalline Diamond Microresonators Mechanical Energy Dissipation in Ultrananocrystalline Diamond Microresonators SEM micrograph of UNCD microresonator SEM micrograph of fabricated UNCD microresonator Researchers in the Nanofabrication and Devices group, in collaboration with the University of Pennsylvania, Advanced Diamond Technologies Inc., and Innovative Micro Technology, have discovered that defects at the grain boundary in ultrananocrystalline diamond (UNCD) hold primary responsibility for the fundamental mechanism of energy dissipation. Because of a high Young's modulus and high sound propagation velocity, UNCD materials hold potential for fabricating high-frequency microelectromechanical (MEMS) resonators. However, their mechanical dissipation at high frequency, which is important for developing high-frequency resonator applications, is not

209

Studying defects created by irradiating molybdenum crystals ...  

NLE Websites -- All DOE Office Websites (Extended Search)

by irradiating molybdenum crystals July 16, 2013 Tweet EmailPrint In order to study irradiation damage and inert gas bubble formation and growth behaviors, and to provide results...

210

Volume 2, Chapter 12: Eliminating Defects and Knowing the Reasons Behind Defects  

E-Print Network (OSTI)

down to the surface.] One should gradually sand (or rasp) the bridge down, checking the results it tight. The defects of the nut and yin­t'o; that is, striking noises, shadow sounds, striking fingers fasteners should not be too tight or too loose. If too tight, then tuning the strings will be difficult

Binkley, Jim

211

A holographic perspective on non-relativistic conformal defects  

E-Print Network (OSTI)

We study defects in non-relativistic conformal field theories. As in the well-studied case of relativistic conformal defects, we find that a useful tool to organize correlation functions is the defect operator expansion (dOPE). We analyze how the dOPE is implemented in theories with a holographic dual, highlighting some interesting aspects of the operator/state mapping in non-relativistic holography.

Andreas Karch; Piotr Surowka; Ethan G. Thompson

2009-03-11T23:59:59.000Z

212

Defective Carbon Nanomaterials as the Cathodes for High ...  

Science Conference Proceedings (OSTI)

Defective carbon nanotubes used as the cathodes for lithium batteries show capacitance of ~580 F/g, which can store lithium ions up to an energy density of...

213

Imaging and Spectroscopy of Chemical and Structural Defects in ...  

Science Conference Proceedings (OSTI)

We present annular dark-field images and electron energy-loss spectra from graphene, and carbon nanotubes with and without structural and chemical defects.

214

Defect in Graphene May Present Bouquet of Possibilities  

Science Conference Proceedings (OSTI)

... rigid lattice already is stronger than steel, but the defects might allow it a little flexibility, making it even more resilient to tearing or fracturing. ...

2013-03-12T23:59:59.000Z

215

Defect Chemistry and Kinetics of Electrons in Ion Conducting Materials  

Science Conference Proceedings (OSTI)

Presentation Title, Defect Chemistry and Kinetics of Electrons in Ion Conducting Materials Recent Results and Applications. Author(s), Hans D. Wiemhfer.

216

Simple intrinsic defects in GaAs : numerical supplement.  

SciTech Connect

This Report presents numerical tables summarizing properties of intrinsic defects in gallium arsenide, GaAs, as computed by density functional theory. This Report serves as a numerical supplement to the results published in: P.A. Schultz and O.A. von Lilienfeld, 'Simple intrinsic defects in GaAs', Modelling Simul. Mater. Sci Eng., Vol. 17, 084007 (2009), and intended for use as reference tables for a defect physics package in device models. The numerical results for density functional theory calculations of properties of simple intrinsic defects in gallium arsenide are presented.

Schultz, Peter Andrew

2012-04-01T23:59:59.000Z

217

Hydrogen-Defect Interactions in the Framework of the Defactant ...  

Science Conference Proceedings (OSTI)

Symposium, Multiscale Approaches to Hydrogen-assisted Degradation of Metals. Presentation Title, Hydrogen-Defect Interactions in the Framework of the...

218

Atomic Scale Modeling of Point Defects in Materials: Coupling Ab ...  

Science Conference Proceedings (OSTI)

Presentation Title, Atomic Scale Modeling of Point Defects in Materials: Coupling Ab Initio and Elasticity ... Electrochemical Shock of Lithium Battery Materials.

219

Modeling the Effect of Stress on Defect Migration and Void ...  

Science Conference Proceedings (OSTI)

The internal stress, in turn, affects the defect dynamic within the material. In this work, we ... Effect of Neutron Radiation Exposure on Low Cycle Fatigue of 304SS

220

Defect in Graphene May Present Bouquet of Possibilities  

Science Conference Proceedings (OSTI)

A class of decorative, flower-like defects in the nanomaterial graphene could have potentially important effects on the material's already unique ...

2012-10-17T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Selective nucleation induced by defect nanostructures: A way to control cobalt disilicide precipitation during ion implantation  

SciTech Connect

In this paper, we show a way to control cobalt disilicide precipitation during Co ion implantation at high temperatures (650 Degree-Sign C) by affecting radiation defects involved in precipitate nucleation and growth. We demonstrate that the relative shares of different precipitate types nucleated by implantation are strongly affected by defect microstructures deliberately created in investigated samples prior to cobalt implantation. Especially interesting is the effect of a dense ensemble of extremely small (1-3 nm) cavities, which promotes the formation of a relatively uniform layer of coherent cobalt disilicide precipitates with a narrow size distribution. In order to better understand the mechanism of the microstructural influence on the precipitate nucleation modes during Co implantation, we investigate the disilicide precipitation using different implantation setups and compare the results with those for cavity-free Si specimens implanted in similar conditions.

Fortuna, F.; Nguyen, M.-A.; Ruault, M.-O. [CSNSM, batiment 108, 91405 Orsay Campus (France); Kirk, M. A. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Borodin, V. A. [NRC 'Kurchatov Institute,' 123182 Moscow (Russian Federation); Ganchenkova, M. G. [NRNU MEPhI, 115409 Moscow (Russian Federation)

2012-12-15T23:59:59.000Z

222

Plug Load Behavioral Change Demonstration Project  

SciTech Connect

This report documents the methods and results of a plug load study of the Environmental Protection Agency's Region 8 Headquarters in Denver, Colorado, conducted by the National Renewable Energy Laboratory. The study quantified the effect of mechanical and behavioral change approaches on plug load energy reduction and identified effective ways to reduce plug load energy. Load reduction approaches included automated energy management systems and behavioral change strategies.

Metzger, I.; Kandt, A.; VanGeet, O.

2011-08-01T23:59:59.000Z

223

Defect detection effectiveness and product quality in global software development  

Science Conference Proceedings (OSTI)

Global software development (GSD) has become a common practice in the software development industry. The main challenge organizations have to overcome is to minimize the effect of organizational diversity on the effectiveness of their GSD collaboration. ... Keywords: defect density, defect detection effectiveness, global software development, software quality

Tihana Galinac Grbac; Darko Huljeni?

2011-06-01T23:59:59.000Z

224

ULTRASONIC DETECTION OF SURFACE-BREAKING RAILHEAD DEFECTS  

Science Conference Proceedings (OSTI)

We recently presented measurements of defects on the railhead, using a novel pitch-catch ultrasonic system comprising of two electro-magnetic acoustic transducers (EMATs) generating and detecting Rayleigh waves. Current systems used on the UK rail network for detecting surface breaking defects are limited in speed (5 mm). The non-contact EMAT system has the potential to operate at higher line speed, improving network inspection coverage. The current system detects signals and performs an FFT in less than 1 ms, and changes in the detected signal amplitude and frequency content are used to characterise defects. A new set of simulated defects on sections of rail have been produced, including half-face slots machined normal to the railhead surface, clusters of angled slots, and pocket defects more typical of real defects. The smallest pocket defects are difficult to detect, with changes in signal amplitude and cut-off falling close to the noise level. However, at chosen higher frequencies a drop in FFT magnitude indicates the presence of a defect, and this indicator can be logically combined with amplitude and cut-off measurements to provide a more reliable result. Preparation for testing on a rotating rail rig at high speeds is ongoing.

Edwards, R. S.; Fan, Y.; Dixon, S. [University of Warwick, Department of Physics, Coventry CV4 7AL (United Kingdom); Papaelias, M.; Davis, C. L.; Roberts, C. [University of Birmingham, School of Engineering, Birmingham (United Kingdom)

2008-02-28T23:59:59.000Z

225

A self-organizing defect tolerant SIMD architecture  

Science Conference Proceedings (OSTI)

The continual decrease in transistor size (through either scaled CMOS or emerging nanotechnologies) promises to usher in an era of tera to peta-scale integration but with increasing defects. Regardless of fabrication methodology (top-down or bottom-up), ... Keywords: DNA, SIMD, Self-organizing, bit-serial, data parallel, defect tolerance, nanocomputing

Jaidev Patwardhan; Chris Dwyer; Alvin R. Lebeck

2007-07-01T23:59:59.000Z

226

Understanding of Defect Physics in Polycrystalline Photovoltaic Materials: Preprint  

DOE Green Energy (OSTI)

The performance of thin-film solar cells is influenced by the quality of interfaces and formation of defects such as point defects, stacking faults, twins, dislocations, and grain boundaries. It is important to understand the defect physics so that appropriate methods may be developed to suppress the formation of harmful defects. Here, we review our understanding of defect physics in thin-film photovoltaic (PV) materials such as Si, CdTe, Cu(In,Ga)Se2 (CIGS), Cu2ZnSnSe2 (CZTSe), and Cu2ZnSnS2 (CZTS) using the combination of nanoscale electron microscopy characterization and density-functional theory (DFT). Although these thin-film PV materials share the same basic structural feature - diamond structure based - the defect physics in them could be very different. Some defects, such as stacking faults and special twins, have similar electronic properties in these thin-film materials. However, some other defects, such as grain boundaries and interfaces, have very different electronic properties in these materials. For example, grain boundaries produce harmful deep levels in Si and CdTe, but they do not produce significant deep levels in CIGS, CZTSe, and CZTS. These explain why passivation is critical for Si and CdTe solar cells, but is less important in CIS and CZTS solar cells. We further provide understanding of the effects of interfaces on the performance of solar cells made of these PV materials.

Yan, Y.

2011-07-01T23:59:59.000Z

227

Defect and Damage Evolution Quantification in Dynamically ...  

Science Conference Proceedings (OSTI)

Design of Pre-Weakening and Evaluation of Structural Safety for Explosive ... Crystallization Temperature of Pd-Cu-Si System Using Integrated Thin Film Samples ... Mechanical Properties of 5083 Aluminium Welds after Manual and Automatic...

228

Research in Hydrogen Passivation of Defects and Impurities in Silicon: Final Report, 2 May 2000-2 July 2003  

DOE Green Energy (OSTI)

This subcontract report describes hydrogenating Si samples by different methods such as low-energy implantation, electron cyclotron resonance (ECR) plasma, and thermal diffusion. The samples were provided through NREL. The experimental work, carried out at Penn State, involved the study of hydrogen interaction with defects, trapping, migration, and formation of complexes. The principal vehicle for the latter study was ion implantation, and the intent to understand mechanisms of defect passivation and activation by hydrogen. NREL implemented a study of hydrogen passivation of impurities and defects in silicon solar cells. The work included theoretical and experimental components performed at different universities. The theoretical studies consisted of the calculation of the structure and parameters related to hydrogen diffusion and interactions of hydrogen with transition-metal impurities in silicon. Experimental studies involved measurements of hydrogen and hydrogen-impurity complexes, and diffusion properties of various species of hydrogen in Si. The experimental work at Penn State included introduction of hydrogen in a variety of PV Si by ECR plasma, low-energy ion implantation, and thermal diffusion. The specific tasks were the evaluation of hydrogen interaction with defects engineered by ion implantation; defect passivation, activation, and migration in hydrogenated Si under thermal anneal; and electrical activity of hydrogen-impurity complexes. Electrical characterization entailed I-V and C-V measurements, spreading resistance, and deep-level transient spectroscopy (DLTS).

Ashok, S.

2004-12-01T23:59:59.000Z

229

Eddy Current Testing for Detecting Small Defects in Thin Films  

SciTech Connect

Presented here is a technique of using Eddy Current based Giant Magneto-Resistance sensor (GMR) to detect surface and sub-layered minute defects in thin films. For surface crack detection, a measurement was performed on a copper metallization of 5-10 microns thick. It was done by scanning the GMR sensor on the surface of the wafer that had two scratches of 0.2 mm, and 2.5 mm in length respectively. In another experiment, metal coatings were deposited over the layers containing five defects with known lengths such that the defects were invisible from the surface. The limit of detection (resolution), in terms of defect size, of the GMR high-resolution Eddy Current probe was studied using this sample. Applications of Eddy Current testing include detecting defects in thin film metallic layers, and quality control of metallization layers on silicon wafers for integrated circuits manufacturing.

Obeid, Simon; Tranjan, Farid M. [Electrical and Computer Engineering Department, UNCC (United States); Dogaru, Teodor [Albany Instruments, 426-O Barton Creek, Charlotte, NC 28262 (United States)

2007-03-21T23:59:59.000Z

230

Nonlinear beam deflection in photonic lattices with negative defects  

Science Conference Proceedings (OSTI)

We demonstrate both theoretically and experimentally that a nonlinear beam can be reflected by a negative defect in a photonic lattice if the incident angle is below a threshold value. Above this threshold angle, the beam simply passes through the defect. This phenomenon occurs in both one- and two-dimensional photonic lattices, and it provides a way to use the incident angle to control beam propagation in a lattice network. If the defect is absent or positive, no evident transition from reflection to transmission occurs. These nonlinear phenomena are also compared with linear nondiffracting-beam propagation in a photonic lattice with a defect, and both similarities and differences are observed. In addition, some important features in linear and nonlinear beam propagations are explained analytically by using a linear model with a delta-function defect.

Wang Jiandong [College of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Ye Zhuoyi; Lou Cibo [TEDA Applied Physical School, Nankai University, Tianjin 300457 (China); Miller, Alexandra; Zhang Peng [Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States); Hu Yi; Chen Zhigang [TEDA Applied Physical School, Nankai University, Tianjin 300457 (China); Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States); Yang Jianke [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401 (United States)

2011-03-15T23:59:59.000Z

231

Solutioning and Aging Behaviors  

Science Conference Proceedings (OSTI)

Aluminum Alloys: Development, Characterization and Applications: Solutioning and Aging Behaviors Sponsored by: TMS Light Metals Division, TMS: Aluminum

232

Nanomechanical Materials Behavior Committee  

Science Conference Proceedings (OSTI)

The Nanomechanical Materials Behavior Committee is part of the Materials Processing & Manufacturing Division;. Our Mission: Focuses on the nanomechanical...

233

Coding-error based defects in enterprise resource planning software: Prevention, discovery, elimination and mitigation  

Science Conference Proceedings (OSTI)

Software defects due to coding errors continue to plague the industry with disastrous impact, especially in the enterprise application software category. Identifying how much of these defects are specifically due to coding errors is a challenging problem. ... Keywords: Code auditing, Coding defects, Defect density, Defect reduction, ERP, Software development, Software testing, Static code analysis

Isaac Woungang; Felix O. Akinladejo; David W. White; Mohammad S. Obaidat

2012-07-01T23:59:59.000Z

234

Research on the Hydrogen Passivation of Defects and Impurities in Si Relevant to Crystalline Si Solar Cell Materials: Final Report, 16 February 2000 -- 15 April 2003  

DOE Green Energy (OSTI)

The goal of this experimental research program is to increase the understanding, at a microscopic level, of hydrogenation processes and passivation mechanisms for crystalline-Si photovoltaics. In our experiments, vibrational spectroscopy was used to study the properties of the interstitial H2 molecule in Si and the transition-metal-hydrogen complexes in Si. The interstitial H2 molecule is formed readily in Si when hydrogen is introduced. Our studies establish that interstitial H2 in Si behaves as a nearly free rotator, solving puzzles about the behavior of this defect that have persisted since the discovery of its vibrational spectrum. The transition metals are common impurities in Si that decrease the minority-carrier lifetime and degrade the efficiencies of solar cells. Therefore, the possibility that transition-metal impurities in Si might be passivated by hydrogen has long been of interest. Our studies of transition-metal-H complexes in Si help to establish the structural and electrical properties of a family of Pt-H complexes in Si, and have made the Pt-H complexes a model system for understanding the interaction of hydrogen with transition-metal impurities in Si.

Stavola, M.

2003-09-01T23:59:59.000Z

235

Systematic study related to the role of initial impurities and irradiation rates in the formation and evolution of complex defects in silicon for detectors in HEP experiments  

E-Print Network (OSTI)

The influence of oxygen and carbon impurities on the concentrations of defects in silicon for detector uses, in complex fields of radiation, characteristic to high energy physics experiments, is investigated in the frame of the quantitative phenomenological model developed previously by the authors and extended in the present paper. Continuous irradiation conditions are considered, simulating realistically the environments for these experiments. The generation rate of primary defects is calculated starting from the projectile - silicon interaction and from the recoil energy redistribution in the lattice. The mechanisms of formation of complex defects are explicitly analysed. Vacancy-interstitial annihilation, interstitial and vacancy migration to sinks, divacancy, vacancy- and interstitial-impurity complex formation and decomposition are considered. Oxygen and carbon impurities present in silicon could monitor the concentration of all stable defects, due to their interaction with vacancies and interstitials. Their role in the mechanisms of formation and decomposition of the following stable defects: V_2, VO, V_2O, C_i, C_iO_i, C_iC_s and VP, is studied. The model predictions cover a generation primary rate of defects between 10^2 pairs/cm3/s and 10^{11} pairs/cm3/s, and could be a useful clue in obtaining harder materials for detectors for space missions, at the new generation of accelerators, as, e.g. LHC, Super-LHC and Eloisatron, or for industrial applications.

Sorina Lazanu; Ionel Lazanu

2003-10-08T23:59:59.000Z

236

Systematic study related to the role of initial impurities and irradiation rates in the formation and evolution of complex defects in silicon for detectors in HEP experiments  

E-Print Network (OSTI)

The influence of oxygen and carbon impurities on the concentrations of defects in silicon for detector uses, in complex fields of radiation, characteristic to high energy physics experiments, is investigated in the frame of the quantitative phenomenological model developed previously by the authors and extended in the present paper. Continuous irradiation conditions are considered, simulating realistically the environments for these experiments. The generation rate of primary defects is calculated starting from the projectile - silicon interaction and from the recoil energy redistribution in the lattice. The mechanisms of formation of complex defects are explicitly analysed. Vacancy-interstitial annihilation, interstitial and vacancy migration to sinks, divacancy, vacancy- and interstitial-impurity complex formation and decomposition are considered. Oxygen and carbon impurities present in silicon could monitor the concentration of all stable defects, due to their interaction with vacancies and interstitials. ...

Lazanu, S; Lazanu, Sorina; Lazanu, Ionel

2004-01-01T23:59:59.000Z

237

Compliant mechanisms  

E-Print Network (OSTI)

The motivation for this work has been a variety of motions like navigation of pipelines, insertion operations in assembly, and gripping actions, which require the adaptation of the mechanism to the external constraints, rather than avoid them. To this effect, efforts have been made in building mechanisms that obtain the required degrees of freedom through deformations rather than explicit joints in them. Although the use of many joints provides the required number of degrees of freedom, it does so at the cost of making the system very bulky and complex. With the advent of new polymers, the possibility of building joint-free mechanisms that fulfil the requirements of adaptation has increased. Based on this approach, a Magneto Active Polymer (MAP) material has been developed here at the Texas A\\&M University, in which the actuation is performed by the conversion of electromagnetic energy into mechanical energy. The initial experimentation has proved the vast potential of the use of such a material and a few mechanisms like a magneto active peristaltic pump, have been designed and tested for the first time using this material. In this mechanism, the pumping action is obtained when a moving magnetic field produces peristaltic waves in the magneto active material shaped as a tube. Also for the first time, experiments have been conducted to analyze the response of the MAP material to a pulsating magnetic field with the intent of using the experimental results to develop a model of the MAP. In developing the design for the peristaltic pump and other conceptual models described in this thesis, ideas have been drawn from the different modes of locomotion and actuators present in lower organisms. These have been good sources of inspiration for the work done in this thesis and they have been documented in detail.

Venkataraghavan, Janarthanan T

2001-01-01T23:59:59.000Z

238

Infrared birefringence imaging of residual stress and bulk defects in multicrystalline silicon  

Science Conference Proceedings (OSTI)

This manuscript concerns the application of infrared birefringence imaging (IBI) to quantify macroscopic and microscopic internal stresses in multicrystalline silicon (mc-Si) solar cell materials. We review progress to date, and advance four closely related topics. (1) We present a method to decouple macroscopic thermally-induced residual stresses and microscopic bulk defect related stresses. In contrast to previous reports, thermally-induced residual stresses in wafer-sized samples are generally found to be less than 5 MPa, while defect-related stresses can be several times larger. (2) We describe the unique IR birefringence signatures, including stress magnitudes and directions, of common microdefects in mc-Si solar cell materials including: {beta}-SiC and {beta}-Si{sub 3}N{sub 4} microdefects, twin bands, nontwin grain boundaries, and dislocation bands. In certain defects, local stresses up to 40 MPa can be present. (3) We relate observed stresses to other topics of interest in solar cell manufacturing, including transition metal precipitation, wafer mechanical strength, and minority carrier lifetime. (4) We discuss the potential of IBI as a quality-control technique in industrial solar cell manufacturing.

Ganapati, Vidya; Schoenfelder, Stephan; Castellanos, Sergio; Oener, Sebastian; Koepge, Ringo; Sampson, Aaron; Marcus, Matthew A.; Lai, Barry; Morhenn, Humphrey; Hahn, Giso; Bagdahn, Joerg; Buonassisi1, Tonio

2010-05-05T23:59:59.000Z

239

Space-radiation-induced point defect formation in optical materials. Ph.D. Thesis  

SciTech Connect

One of the central problems man has faced in his exploration of space is the long and short term effects of the space environment on the performance of spacecraft systems. The results presented in this dissertation represent the first time a definite connection has been made between the space-induced damage of optical systems and the microscopic mechanisms of point defect formation that lead to the damage. Point defect formation was observed in two, and possibly three different optical materials subjected to short-duration space exposure. Three calcium fluoride, two lithium fluoride, and three magnesium fluoride samples were flown on Space Shuttle flight STS-46 as part of the Evaluation of Oxygen Interactions with Materials - Third Phase experiment. Pre-flight and post-flight optical absorption measurements were performed on all of the samples. With the possible exception of the magnesium fluoride samples, every sample clearly showed the formation of F-centers in that section of the sample that was exposed to the low earth orbit environment. Analysis of the flight samples and laboratory experiments on control samples identify solar vacuum ultraviolet radiation as the most probable primary cause of the defect formation.

Allen, J.L.

1994-01-01T23:59:59.000Z

240

Acceleration Mechanisms  

E-Print Network (OSTI)

Glossary I. Background and context of the subject II. Stochastic acceleration III. Resonant scattering IV. Diffusive shock acceleration V. DSA at multiple shocks VI. Applications of DSA VII. Acceleration by parallel electric fields VIII. Other acceleration mechanisms IX. Future directions X. Appendix: Quasilinear equations XI. Bibliography

Melrose, D B

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Heavy and Overweight Vehicle Defects Interim Report  

SciTech Connect

The Federal Highway Administration (FHWA), along with the Federal Motor Carrier Safety Administration (FMCSA), has an interest in overweight commercial motor vehicles, how they affect infrastructure, and their impact on safety on the nation s highways. To assist both FHWA and FMCSA in obtaining more information related to this interest, data was collected and analyzed from two separate sources. A large scale nationwide data collection effort was facilitated by the Commercial Vehicle Safety Alliance as part of a special study on overweight vehicles and an additional, smaller set, of data was collected from the state of Tennessee which included a much more detailed set of data. Over a six-month period, 1,873 Level I inspections were performed in 18 different states that volunteered to be a part of this study. Of the 1,873 inspections, a vehicle out-of-service (OOS) violation was found on 44.79% of the vehicles, a rate significantly higher than the national OOS rate of 27.23%. The main cause of a vehicle being placed OOS was brake-related defects, with approximately 30% of all vehicles having an OOS brake violation. Only about 4% of vehicles had an OOS tire violation, and even fewer had suspension and wheel violations. Vehicle weight violations were most common on an axle group as opposed to a gross vehicle weight violation. About two thirds of the vehicles cited with a weight violation were overweight on an axle group with an average amount of weight over the legal limit of about 2,000 lbs. Data collection is scheduled to continue through January 2014, with more potentially more states volunteering to collect data. More detailed data collections similar to the Tennessee data collection will also be performed in multiple states.

Siekmann, Adam [ORNL; Capps, Gary J [ORNL

2012-12-01T23:59:59.000Z

242

Adaptive mechanism design: a metalearning approach  

Science Conference Proceedings (OSTI)

Auction mechanism design has traditionally been a largely analytic process, relying on assumptions such as fully rational bidders. In practice, however, bidders often exhibit unknown and variable behavior, making them difficult to model and complicating ... Keywords: auctions, machine learning, mechanism design, metalearning

David Pardoe; Peter Stone; Maytal Saar-Tsechansky; Kerem Tomak

2006-08-01T23:59:59.000Z

243

Hopf Bifurcation Analysis for a Mechanical Centrifugal Flywheel Governor System  

Science Conference Proceedings (OSTI)

The complex dynamic behavior of the mechanical centrifugal flywheel governor system is studied. The dynamical equation of the system is established using Lagrangian and Newtons second law. The bifurcation behavior and stability of the mechanical ... Keywords: centrifugal governor, Lyapunov exponents, chaos, chaos synchronization, Poincar map

Jian-Gang Zhang; Jian-Ning Yu; Yan-Dong Chu; Xian-Feng Li

2008-10-01T23:59:59.000Z

244

Do the Defects Make It Work? Defect Engineering in Pi-Conjugated Polymers and Their Solar Cells: Preprint  

DOE Green Energy (OSTI)

The charged defect density in common pi-conjugated polymers such as poly(3-hexylthiophene), P3HT, is around 1018 cm-3. Despite, or perhaps because of, this huge defect density, bulk heterojunction solar cells made from these polymers and a C60 derivative such as PCBM exhibit some of the highest efficiencies (~5%) yet obtained in solid state organic photovoltaic cells. We discuss defects in molecular organic semiconductors and in pi-conjugated polymers. These defects can be grouped in two categories, covalent and noncovalent. Somewhat analogous to treating amorphous silicon with hydrogen, we introduce chemical methods to modify the density and charge of the covalent defects in P3HT by treating it with electrophiles such as dimethyl sulfate and nucleophiles such as sodium methoxide. The effects of these treatments on the electrical and photovoltaic properties and stability of organic PV cells is discussed in terms of the change in the number and chemical properties of the defects. Finally, we address the question of whether the efficiency of OPV cells requires the presence of these defects which function as adventitious p-type dopants. Their presence relieves the resistance limitations usually encountered in cleaner organic semiconductors and can create built-in electric fields at junctions.

Wang, D.; Reese, M.; Kopidakis N.; Gregg, B. A.

2008-05-01T23:59:59.000Z

245

Nanocrystalline alloys : enhanced strengthening mechanisms and mechanically-driven structural evolution  

E-Print Network (OSTI)

Nanocrystalline materials have experienced a great deal of attention in recent years, largely due to their impressive array of physical properties. In particular, nanocrystalline mechanical behavior has been of interest, ...

Rupert, Timothy J. (Timothy John)

2011-01-01T23:59:59.000Z

246

Investigation of Gettering Mechanisms in Crystalline Silicon: Final Subcontract Report, 21 July 1997--30 September 2003  

DOE Green Energy (OSTI)

In this investigation, various aspects of the mechanisms of gettering contaminant impurities away from device active regions in Si have been systematically conducted. Also systematically studied are the modeling of electrical activity of metallic precipitates in Si based on the Schottky effect. With these studies, our knowledge of gettering in Si and on the electrical activity of metallic precipitates in Si has become substantially complete in the sense that interpretations of major experimental results have become self- and mutually consistent. The purpose of conducting the studies supported by this project was to obtain consistent interpretations of existing experimental results, as well as to conduct the needed new experiments, concerning the various phenomena associated with gettering in Si. The investigated gettering method is that by using an Al layer, and the involved works span from studies concerning basic point defect behaviors during gettering to studies of application of the gettering method to improve multicrystalline Si minority-carrier diffusion lengths. A preliminary study of the effect of gettering in affecting the solar cell efficiency has been conducted. Moreover, a study of the electrical behavior of precipitated metallic impurities in Si based on the Schottky property of the precipitates, which is a newly proposed physical mechanism, has also been conducted. As a result of the present studies, our knowledge on such phenomena have become substantially more systematic.

Tan, T. Y.

2004-05-01T23:59:59.000Z

247

The Impact and Control of Defects in III-V/Si Heterostructures for ...  

Science Conference Proceedings (OSTI)

Accelerated Light Induced Degradation, ALID, for Monitoring of Defects in PV Silicon Wafers and Solar Cells Analysis of Defect Formation in 4H-SiC Epitaxial

248

Do the Defects Make it Work? Defect Engineering in ..pi.. - Conjugated Polymer Films and Their Solar Cells (Presentation)  

DOE Green Energy (OSTI)

The summaries of this report are: (1) charged defects produce 10{sup 15}-10{sup 17} cm{sup -3} free carriers; (2) treatment with nucleophiles decreases p{sub f} and {sigma} while treatment with electrophiles does not change p{sub f} but increases {sigma}; (3) both treatments increase {mu}{sub p}, L{sub ex} and stability against photo-degradation; (4) charged defects can improve OPV by increasing conductivity and creating interfacial electric fields but they hurt {mu}{sub p}, L{sub ex} and chemical stability; and (5) a better way--synthesize materials without covalent defects and dope with purposely added, bound dopants.

Gregg, B. A.; Wang, D.; Reese, M. O.; Kopidakis, N.

2008-05-01T23:59:59.000Z

249

22.314J / 1.56J / 2.084J Structural Mechanics in Nuclear Power Technology, Spring 2004  

E-Print Network (OSTI)

Structural components in nuclear power plant systems, their functional purposes, operating conditions, and mechanical-structural design requirements. Combines mechanics techniques with models of material behavior to determine ...

Kazimi, Mujid S.

250

Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder  

NLE Websites -- All DOE Office Websites (Extended Search)

Defect Analysis of Vehicle Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder A China Paper on Type 4 Cylinder, translated and presented by J. P. Hsu, PhD, Smart Chemistry Reason for Defect Analysis of CNG Composite Cylinder * Safety Issue - Four explosion accidents of auto used CNG composite material cylinders resulting huge personnel and vehicles loss. * Low Compliance Rate - Inspect 12119 Auto used CNG composite cylinders and only 3868 are qualified with compliance rate of 32%. Plastic CNG Composite Cylinder Process Fitting Internal Plastic Liner External Composite Layer Metal Fitting HDPE Cylinder Liner * HDPE has a high density, great stiffness, good anti-permeability and high melting point, but poor environmental stress cracking Resistance (ESCR). * The defects of cylinder liner quality can be

251

NHTSA's Office of Defects Investigation (ODI) - Technical Service Bulletins  

NLE Websites -- All DOE Office Websites (Extended Search)

NHTSA's Office of Defects Investigation (ODI) - Technical Service Bulletins NHTSA's Office of Defects Investigation (ODI) - Technical Service Bulletins System (TSBS) - Downloadable file Manufacturing Data/Tools Research/Tech Services Apps Challenges Blogs Let's Talk Manufacturing You are here Data.gov » Communities » Manufacturing » Data NHTSA's Office of Defects Investigation (ODI) - Technical Service Bulletins System (TSBS) - Downloadable file Dataset Summary Description The Technical Service Bulletins data contains summaries of the Manufacturers' Technical Service Bulletins by single year, make and model. An optional item of Vehicle Component may be also available. (The data does not contain all the service bulletins generated by a manufacturer. Bulletins for safety recalls in general are not included, and also bulletins which may not pertain to a defect may not be included.)

252

Method and apparatus for inspecting reflection masks for defects  

SciTech Connect

An at-wavelength system for extreme ultraviolet lithography mask blank defect detection is provided. When a focused beam of wavelength 13 nm is incident on a defective region of a mask blank, three possible phenomena can occur. The defect will induce an intensity reduction in the specularly reflected beam, scatter incoming photons into an off-specular direction, and change the amplitude and phase of the electric field at the surface which can be monitored through the change in the photoemission current. The magnitude of these changes will depend on the incident beam size, and the nature, extent and size of the defect. Inspection of the mask blank is performed by scanning the mask blank with 13 nm light focused to a spot a few .mu.m in diameter, while measuring the reflected beam intensity (bright field detection), the scattered beam intensity (dark-field detection) and/or the change in the photoemission current.

Bokor, Jeffrey (Oakland, CA); Lin, Yun (Berkeley, CA)

2003-04-29T23:59:59.000Z

253

Defect modes in one-dimensional granular crystals  

E-Print Network (OSTI)

We study the vibrational spectra of one-dimensional statically compressed granular crystals (arrays of elastic particles in contact) containing light-mass defects. We focus on the prototypical settings of one or two spherical ...

Boechler, Nicholas Sebastian

254

Quality improvement and control based on defect reduction  

E-Print Network (OSTI)

This thesis addresses the quality improvement in a printing process at a food packaging company now experiencing hundreds of printing defects. Methodologies of Define, Measure, Analyze, Improve, and Control (DMAIC), and ...

Dai, Qi, M. Eng. Massachusetts Institute of Technology

2010-01-01T23:59:59.000Z

255

Nano-chemo-mechanics of advanced materials for hydrogen storage and lithium battery applications .  

E-Print Network (OSTI)

??Chemo-mechanics studies the material behavior and phenomena at the interface of mechanics and chemistry. Material failures due to coupled chemo-mechanical effects are serious roadblocks in (more)

Huang, Shan

2011-01-01T23:59:59.000Z

256

Automated defect spatial signature analysis for semiconductor manufacturing process  

DOE Patents (OSTI)

An apparatus and method for performing automated defect spatial signature alysis on a data set representing defect coordinates and wafer processing information includes categorizing data from the data set into a plurality of high level categories, classifying the categorized data contained in each high level category into user-labeled signature events, and correlating the categorized, classified signature events to a present or incipient anomalous process condition.

Tobin, Jr., Kenneth W. (Harriman, TN); Gleason, Shaun S. (Knoxville, TN); Karnowski, Thomas P. (Knoxville, TN); Sari-Sarraf, Hamed (Knoxville, TN)

1999-01-01T23:59:59.000Z

257

Graphene materials having randomly distributed two-dimensional structural defects  

DOE Patents (OSTI)

Graphene-based storage materials for high-power battery applications are provided. The storage materials are composed of vertical stacks of graphene sheets and have reduced resistance for Li ion transport. This reduced resistance is achieved by incorporating a random distribution of structural defects into the stacked graphene sheets, whereby the structural defects facilitate the diffusion of Li ions into the interior of the storage materials.

Kung, Harold H; Zhao, Xin; Hayner, Cary M; Kung, Mayfair C

2013-10-08T23:59:59.000Z

258

Defect reaction network in Si-doped InP : numerical predictions.  

Science Conference Proceedings (OSTI)

This Report characterizes the defects in the defect reaction network in silicon-doped, n-type InP deduced from first principles density functional theory. The reaction network is deduced by following exothermic defect reactions starting with the initially mobile interstitial defects reacting with common displacement damage defects in Si-doped InP until culminating in immobile reaction products. The defect reactions and reaction energies are tabulated, along with the properties of all the silicon-related defects in the reaction network. This Report serves to extend the results for intrinsic defects in SAND 2012-3313: %E2%80%9CSimple intrinsic defects in InP: Numerical predictions%E2%80%9D to include Si-containing simple defects likely to be present in a radiation-induced defect reaction sequence.

Schultz, Peter Andrew

2013-10-01T23:59:59.000Z

259

Point defects and transport mechanisms in transparent conducting oxides of intermediate conductivity  

E-Print Network (OSTI)

and indium-tin oxide (ITO), would enable all-oxide and all-transparent electronics and optoelectronics [3-type TCO with properties (especially mobility) comparable to the best n-type TCOs, such as tin oxide Renewable Energy Laboratory. References [1] H. Kawazoe, M. Yasukawa, H. Hyodo, M. Kurita, H. Yanagi, H

Poeppelmeier, Kenneth R.

260

Structural hierarchies define toughness and defect-tolerance despite simple and mechanically inferior brittle building blocks  

E-Print Network (OSTI)

Mineralized biological materials such as bone, sea sponges or diatoms provide load-bearing and armor functions and universally feature structural hierarchies from nano to macro. Here we report a systematic investigation ...

Sen, Dipanjan

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Overexpressed of RAD51 suppresses recombination defects: a possible mechanism to reverse genomic instability  

E-Print Network (OSTI)

Sasaki, M.S. , Sonoda, E. , Fukushima, T. , Morrison, C. ,M.S. , Tachiiri, S. , Fukushima, T. , Sonoda, E. , Schild,

Schild, David

2010-01-01T23:59:59.000Z

262

Mechanical properties of nanophase materials  

SciTech Connect

It has become possible in recent years to synthesize new materials under controlled conditions with constituent structures on a nanometer size scale (below 100 nm). These novel nanophase materials have grain-size dependent mechanical properties significantly different than those of their coarser-grained counterparts. For example, nanophase metals are much stronger and apparently less ductile than conventional metals, while nanophase ceramics are more ductile and more easily formed than conventional ceramics. The observed mechanical property changes are related to grain size limitations and/or the large percentage of atoms in grain boundary environments; they can also be affected by such features as flaw populations, strains and impurity levels that can result from differing synthesis and processing methods. An overview of what is presently known about the mechanical properties of nanophase materials, including both metals and ceramics, is presented. Some possible atomic mechanisms responsible for the observed behavior in these materials are considered in light of their unique structures.

Siegel, R.W. [Argonne National Lab., IL (United States); Fougere, G.E. [Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering

1993-11-01T23:59:59.000Z

263

A Theoretical Study of the Interactions of In+ and In+3 with a Stone-Wales Defect Single-Walled Carbon Nanotubes.  

DOE Green Energy (OSTI)

Experimental techniques [1] have demonstrated the controllable, reversible and mass transport exchange of indium nanocrystals along surfaces of multi-walled carbon nanotubes (MWCNTs). In particular, at certain sites robust nucleation occurs suggesting preferred locations for controlled manipulation. We believe these site locations represent structural defects, like rehybridization, incomplete bonding and topological defects within the carbon network. Although minute, these defects can drastically modify the electrical, chemical and mechanical properties of CNTs. This study was devoted to understand the role of structural defects, specifically a Stone-Wales (SW) defect in the surface transport and interaction properties of the In{sup +1} and In{sup +3} for both the singlet and triplet state. The effects of CNT surface curvature on In+1 and In{sup +3} is also studied and compared to graphite. Geometries of complexes were optimized at the B3LYP level. The standard 6-31G(d) basis set was used for carbon and hydrogen atoms while an effective core potential (ECP) was used for indium. All calculations were performed using the Gaussian 03 suite of programs. The computed Mulliken charges and HOMOLUMO gap energies, interactions and interaction energy (corrected by the basis set superposition error) of the systems have been studied and will be discussed. Figure 1 represents the comparison of the molecular electrostatic potential maps for (a) In{sup +} and (b) In{sup +3} with a SW defect CNT.

Simeon, T; Balasubramanian, K; Leszczynski, J

2008-10-02T23:59:59.000Z

264

Probabilistic timed behavior trees  

Science Conference Proceedings (OSTI)

The Behavior Tree notation has been developed as a method for systematically and traceably capturing user requirements. In this paper we extend the notation with probabilistic behaviour, so that reliability, performance, and other dependability properties ... Keywords: behavior trees, model checking, probabilities, timed automata

Robert Colvin; Lars Grunske; Kirsten Winter

2007-07-01T23:59:59.000Z

265

Research in Hydrogen Passivation of Defects and Impurities in Silicon: Final Subcontract Report, 2 May 2000--2 July 2003  

DOE Green Energy (OSTI)

Our work consists of hydrogenating silicon (Si) samples by different methods such as low-energy implantation, electron cyclotron resonance (ECR) plasma, and thermal diffusion. The samples will be provided through NREL. The experimental work carried out at Penn State involves the study of hydrogen interaction with defects, trapping, migration, and formation of complexes. The principal vehicle for the latter study will be ion implantation, and the intent is to understand mechanisms of defect passivation and activation by hydrogen. The theoretical studies will consist of the calculation of the structure and parameters related to hydrogen diffusion and interactions of hydrogen with transition metal impurities in silicon. Experimental studies will involve measurements of hydrogen and hydrogen-impurity complexes, and diffusion properties of various species of hydrogen in Si. The experimental work at Penn State includes introduction of hydrogen in a variety of photovoltaic Si by ECR plasma, low-energy ion implantation, and thermal diffusion. The specific tasks will be the evaluation of hydrogen interaction with defects engineered by ion implantation; defect passivation, activation, and migration in hydrogenated Si under thermal anneal; and electrical activity of hydrogen-impurity complexes. Electrical characterization will entail I-V and C-V measurements, spreading resistance, and deep-level transient spectroscopy.

Ashok, S.

2004-05-01T23:59:59.000Z

266

A Hierarchical Upscaling Method for Predicting Strength of Materials under Thermal, Radiation and Mechanical loading - Irradiation Strengthening Mechanisms in Stainless Steels  

SciTech Connect

Stainless steels based on Fe-Cr-Ni alloys are the most popular structural materials used in reactors. High energy particle irradiation of in this kind of polycrystalline structural materials usually produces irradiation hardening and embrittlement. The development of predictive capability for the influence of irradiation on mechanical behavior is very important in materials design for next-generation reactors. Irradiation hardening is related to structural information crossing different length scale, such as composition, dislocation, crystal orientation distribution and so on. To predict the effective hardening, the influence factors along different length scales should be considered. A multiscale approach was implemented in this work to predict irradiation hardening of iron based structural materials. Three length scales are involved in this multiscale model: nanometer, micrometer and millimeter. In the microscale, molecular dynamics (MD) was utilized to predict on the edge dislocation mobility in body centered cubic (bcc) Fe and its Ni and Cr alloys. On the mesoscale, dislocation dynamics (DD) models were used to predict the critical resolved shear stress from the evolution of local dislocation and defects. In the macroscale, a viscoplastic self-consistent (VPSC) model was applied to predict the irradiation hardening in samples with changes in texture. The effects of defect density and texture were investigated. Simulated evolution of yield strength with irradiation agrees well with the experimental data of irradiation strengthening of stainless steel 304L, 316L and T91. This multiscale model we developed in this project can provide a guidance tool in performance evaluation of structural materials for next-generation nuclear reactors. Combining with other tools developed in the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program, the models developed will have more impact in improving the reliability of current reactors and affordability of new reactors.

Li, Dongsheng; Zbib, Hussein M.; Garmestani, Hamid; Sun, Xin; Khaleel, Mohammad A.

2011-07-01T23:59:59.000Z

267

Strengthening Concepts & Mechanical Behavior of Ni-Base Alloys in ...  

Science Conference Proceedings (OSTI)

These alloys are among several that offer the best potential for building steam turbine components for a power plant operating at ?1400F. Design strategy,...

268

Effects of Environments on Mechanical Behavior of High  

Science Conference Proceedings (OSTI)

Oct 27, 2009 ... Environmental Degradation and Protection of High Temperature Alloys: Effects of ... Jr, RPSEA: Research Partnership to Secure Energy For America ... the Implications for Life Management Approaches: Michael Caton1; Sushant Jha2 .... heat exchanger in the next generation nuclear plant was evaluated by...

269

236 Mechanical Behavior of Pure Aluminum Fabricated by Equal ...  

Science Conference Proceedings (OSTI)

... of LiMnxFe1-xPO4 Glass and Glass-Ceramics for Lithium Ion Battery .... and Comparing the Inhibition Effect of Chromate, Bromate and Molybdate on the...

270

Behavioral/Systems/Cognitive Potential Network Mechanisms Mediating  

E-Print Network (OSTI)

with the multisensory communication signals. Key words: spike-field coherence; multisensory; gamma band; local field pure tones, frequency-modulated sweeps, noise bursts, clicks, and vocalizations. Using the analog multi) was considered the onset of a multisensory response (Guthrie and Buchwald, 1991; Mur- ray et al., 2004). Spectral

Kopell, Nancy

271

130- Mechanical Behavior of Carbon Nanotube Reinforced Carbon ...  

Science Conference Proceedings (OSTI)

125- Influence of Gas Flow Rate Ratio on the Structural Properties of a-SiC:H Prepared by ... 145- The Synergy of XRD and XRF in a Shale and Slate Analysis.

272

Effect of Heat Treatment on Fatigue Behavior and Mechanical ...  

Science Conference Proceedings (OSTI)

The effect of heat treatment on the rotating beam fatigue strength of .... E9: Effect of Shot Peening on Bending Strength of AZ31 Magnesium Alloy Pipe Effect of...

273

Mechanical Behavior of Biological Materials II - Programmaster.org  

Science Conference Proceedings (OSTI)

Mar 2, 2011... that consists of abrasion resistant teeth anchored to a flexible stylus that the organism uses to abrade rocky substrates to reach algae.

274

SAGBO Mechanism on High Temperature Cracking Behavior of Ni ...  

Science Conference Proceedings (OSTI)

mode I stress intensity factor, Q is the activation energy, R is the universal gas constant and T is the absolute temperature. Accordingly, a plot of log (da/dt)...

275

Structure and Mechanical Behavior of Fish Scales - Programmaster ...  

Science Conference Proceedings (OSTI)

The scales of two large fish, Arapaima gigas (a large Amazon basin fish) and Atractosteus spatula (the largest North American fresh water fish) are characterized...

276

DISSERTATION: Mechanical Behavior of Gas Turbine Coatings - TMS  

Science Conference Proceedings (OSTI)

Oct 11, 2007 ... ABSTRACT: Coatings are frequently applied on gas turbine components in order to restrict surface degradation such as corrosion and...

277

237 Mechanical Properties and Oxidation Behavior of Spark Plasma ...  

Science Conference Proceedings (OSTI)

005 Calcium Phosphates for Drug Carrier: Adsorption and Release Kinetics of Drugs ... 058 Properties Optimization of Refractory Mineral Resources in China.

278

Mechanical Behavior of Biological Materials I: Bone and Teeth  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... These cells participate in the regenerative process through ... rise to overall loading-unloading hysteresis and cyclic dissipation of energy.

279

Mechanical Behavior of Technological Coatings and Thin Films  

Science Conference Proceedings (OSTI)

New green coatings made from renewable materials or using green manufacturing processes are sought in addition to traditional ... Just click on the button.

280

Phase Behavior and Corrosion Mechanisms of Reservoir Fluids ...  

Science Conference Proceedings (OSTI)

Corrosion of Mild Steel in Extreme Oil and Gas Environments Corrosion ... Fluorescent Nanoparticle Tracers for Oil Exploration and Production Formation of...

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Mechanical Behavior of Sisal and Carbon Fibers Reinforced Epoxy ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2013. Symposium, Green Composite Materials: Development, Manufacturing and Testing.

282

Mechanical behavior and microstructure of self-assembling oligopeptide gels  

E-Print Network (OSTI)

Hydrogels have become widely used in the fields of tissue engineering and drug delivery. One class of hydrogel is formed from synthetic oligopeptides that self-assemble into a solution of beta-sheet filaments. These filaments ...

Hammond, Nathan Allen

2010-01-01T23:59:59.000Z

283

Evaluation of Microstructure and Mechanical Behavior of Cu Based ...  

Science Conference Proceedings (OSTI)

Author(s), Jonathan Nguyen, Troy Topping, Hidemi Kato, Yizhang Zhou, Enrique Lavernia. On-Site Speaker (Planned), Jonathan Nguyen. Abstract Scope, Cu-Zr...

284

009- Fracture Behavior and Mechanical Properties of Obsidian ...  

Science Conference Proceedings (OSTI)

125- Influence of Gas Flow Rate Ratio on the Structural Properties of a-SiC:H Prepared by ... 145- The Synergy of XRD and XRF in a Shale and Slate Analysis.

285

Mechanism and Behavioral Context of Male Sex Pheromone ...  

Science Conference Proceedings (OSTI)

were excised from host puparia 12 days before eclosion ... at 70eV. Helium (1 ml/min) was used as carrier gas. Initial oven temperature was 80C, increased at

286

Structure and Mechanical Behavior of Amorphous and Crystalline ...  

Science Conference Proceedings (OSTI)

Mar 13, 2012 ... Program Organizers: Jian Wang, Los Alamos National Laboratory; Nathan ... under external fields would allow interface engineering to create the best ... the Materials Sciences and Engineering Division, Office of Basic Energy...

287

Microstructural and Mechanical Behavior of Al-Mg-Si Alloy ...  

Science Conference Proceedings (OSTI)

K. K. Chawla's Seminal Contributions to the Field of Metal Matrix Composites Structural Health Monitoring of Wind Turbine Blades Studies of Nanocrystalline ...

288

Sintering Behavior, Mechanical Properties and Wear Performance of ...  

Science Conference Proceedings (OSTI)

Atomic -Scale Characterization of Nb-Doped SrTiO?3 Nanostructures for .... Metal Oxide Nanofibers Produced by a ForceSpinning Method for Battery Electrodes.

289

F8: Study on Lump Ore Decrepitation Behavior Mechanism  

Science Conference Proceedings (OSTI)

A8: Microstructural Investigation of Nano-Calcium Phosphates Doped with Fluoride Ions .... D7: Surfactant Structureproperty Relationship: Effect of Polypropylene ... E4: The Effect of Monobutyl Ether Ethylene Glycol on the Conductivity and...

290

Mechanical Behavior of Green Materials - Programmaster.org  

Science Conference Proceedings (OSTI)

Oct 30, 2013 ... Nanoindenation results elucidating the effect of adhesive infiltration on hygromechanical cell wall properties in wood-adhesive bondlines will...

291

Optical and mechanical behavior of the optical fiber infrasound sensor  

E-Print Network (OSTI)

the Comprehensive Nuclear Test Ban Treaty. The mostfrom Nuclear Ex- plosions Part II: The Soviet Test of 30

DeWolf, Scott

2009-01-01T23:59:59.000Z

292

Effects of Thermo-Mechanical Treatments on Deformation Behavior ...  

Science Conference Proceedings (OSTI)

NRC/EPRI Welding Residual Stress Validation Program (Phase III) On the Microstructure of Alloy 600 SCC Cracks Observed by TEM on PWR SG Pulled Tubes...

293

Long-Term Mechanical Behavior of Some ODS Alloys  

Science Conference Proceedings (OSTI)

P=IC+273)(20+log ... stress (a) and time (t) data are plotted on log-log scales, there is some .... These trends have also been quantified using equations [41.

294

Microstructural and Mechanical Property Behaviors of A Large ...  

Science Conference Proceedings (OSTI)

Analysis of Residence Time Distribution (RTD) of Fluid Flows in a Four Strand Delta-shaped Tundish Operating Under Isothermal and Non-isothermal...

295

Effect of Compositional Modifications on the Mechanical Behavior of ...  

Science Conference Proceedings (OSTI)

The metallurgy and phase transformations in both alloys are well documented (l- 3). ... 990C / 1 Oh / oil quenching. Precipitation ... nickel-base alloys reduces the total 0 and S content via the formation of CsO,, CsO,S and. Ce& compounds...

296

Context-based automated defect classification system using multiple morphological masks  

DOE Patents (OSTI)

Automatic detection of defects during the fabrication of semiconductor wafers is largely automated, but the classification of those defects is still performed manually by technicians. This invention includes novel digital image analysis techniques that generate unique feature vector descriptions of semiconductor defects as well as classifiers that use these descriptions to automatically categorize the defects into one of a set of pre-defined classes. Feature extraction techniques based on multiple-focus images, multiple-defect mask images, and segmented semiconductor wafer images are used to create unique feature-based descriptions of the semiconductor defects. These feature-based defect descriptions are subsequently classified by a defect classifier into categories that depend on defect characteristics and defect contextual information, that is, the semiconductor process layer(s) with which the defect comes in contact. At the heart of the system is a knowledge database that stores and distributes historical semiconductor wafer and defect data to guide the feature extraction and classification processes. In summary, this invention takes as its input a set of images containing semiconductor defect information, and generates as its output a classification for the defect that describes not only the defect itself, but also the location of that defect with respect to the semiconductor process layers.

Gleason, Shaun S. (Knoxville, TN); Hunt, Martin A. (Knoxville, TN); Sari-Sarraf, Hamed (Lubbock, TX)

2002-01-01T23:59:59.000Z

297

Limitation of the Open-Circuit Voltage Due to Metastable Intrinsic Defects in Cu(In,Ga)Se2 and Strategies to Avoid These Defects: Preprint  

DOE Green Energy (OSTI)

This paper summarizes using first-principles defect theory to investigate the role of intrinsic point defects in the limitation of the open-circuit voltage (VOC) in Cu(In,Ga)Se2 solar cells.

Lany, S.; Zunger, A.

2008-05-01T23:59:59.000Z

298

Development of complex robotic systems using the behavior-based control architecture iB2C  

Science Conference Proceedings (OSTI)

This paper presents a development methodology for complex robotic systems using the behavior-based control architecture iB2C (integrated Behavior-Based Control). It is shown how architectural principles support several behavior-based mechanisms, e.g. ... Keywords: Behavior-based control, Development process, System analysis

Martin Proetzsch; Tobias Luksch; Karsten Berns

2010-01-01T23:59:59.000Z

299

Ultrasonic imaging system for in-process fabric defect detection  

DOE Patents (OSTI)

An ultrasonic method and system are provided for monitoring a fabric to identify a defect. A plurality of ultrasonic transmitters generate ultrasonic waves relative to the fabric. An ultrasonic receiver means responsive to the generated ultrasonic waves from the transmitters receives ultrasonic waves coupled through the fabric and generates a signal. An integrated peak value of the generated signal is applied to a digital signal processor and is digitized. The digitized signal is processed to identify a defect in the fabric. The digitized signal processing includes a median value filtering step to filter out high frequency noise. Then a mean value and standard deviation of the median value filtered signal is calculated. The calculated mean value and standard deviation are compared with predetermined threshold values to identify a defect in the fabric.

Sheen, Shuh-Haw (Naperville, IL); Chien, Hual-Te (Naperville, IL); Lawrence, William P. (Downers Grove, IL); Raptis, Apostolos C. (Downers Grove, IL)

1997-01-01T23:59:59.000Z

300

Collision Energy Dependence of Defect Formation in Graphene  

SciTech Connect

Molecular dynamics simulations are performed using an empirical potential to simulate the collision process of an energetic carbon atom hitting a graphene sheet. According to the different impact locations within the graphene sheet, the incident threshold energies of different defects caused by the collision are determined to be 22 eV for a single vacancy, 36 eV for a divacancy, 60 eV for a Stone-Wales defect, and 65 eV for a hexavacancy. Study of the evolution and stability of the defects formed by these collisions suggests that the single vacancy reconstructs into a pentagon pair and the divacancy transforms into a pentagon-octagon-pentagon configuration. The displacement threshold energy in graphene is investigated by using the dynamical method, and a reasonable value 22.42 eV is clarified by eliminating the heating effect induced by the collision.

Mao, Fei [Beijing Normal University; Zhang, Chao [Beijing Normal University; Zhang, Yanwen [ORNL; Zhang, Fenf-Shou [Beijing Normal University

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Probing Atoms' Disorderly Behavior  

Science Conference Proceedings (OSTI)

... models, these phase fluctuations are thought to be a mechanism behind the superconducting phase transition in high-temperature superconductors ...

2013-01-03T23:59:59.000Z

302

INDEXING MECHANISM  

DOE Patents (OSTI)

A device is presented for loading and unloading fuel elements containing material fissionable by neutrons of thermal energy. The device comprises a combination of mechanical features Including a base, a lever pivotally attached to the base, an Indexing plate on the base parallel to the plane of lever rotation and having a plurality of apertures, the apertures being disposed In rows, each aperture having a keyway, an Index pin movably disposed to the plane of lever rotation and having a plurality of apertures, the apertures being disposed in rows, each aperture having a keyway, an index pin movably disposed on the lever normal to the plane rotation, a key on the pin, a sleeve on the lever spaced from and parallel to the index pin, a pair of pulleys and a cable disposed between them, an open collar rotatably attached to the sleeve and linked to one of the pulleys, a pin extending from the collar, and a bearing movably mounted in the sleeve and having at least two longitudinal grooves in the outside surface.

Kock, L.J.

1959-09-22T23:59:59.000Z

303

Mechanics of Lithiation in Silicon  

Science Conference Proceedings (OSTI)

Atomic Scale Modeling of Point Defects in Materials: Coupling Ab Initio and Elasticity Approaches ... Electrochemical Shock of Lithium Battery Materials.

304

Multi-level scanning method for defect inspection  

DOE Patents (OSTI)

A method for performing scanned defect inspection of a collection of contiguous areas using a specified false-alarm-rate and capture-rate within an inspection system that has characteristic seek times between inspection locations. The multi-stage method involves setting an increased false-alarm-rate for a first stage of scanning, wherein subsequent stages of scanning inspect only the detected areas of probable defects at lowered values for the false-alarm-rate. For scanning inspection operations wherein the seek time and area uncertainty is favorable, the method can substantially increase inspection throughput.

Bokor, Jeffrey (Oakland, CA); Jeong, Seongtae (Richmond, CA)

2002-01-01T23:59:59.000Z

305

EUV Dark-Field Microscopy for Defect Inspection  

SciTech Connect

An actinic EUV microscope for defect detection on mask blanks for operation in dark field using a table-top discharge-produced plasma source has been developed. Several test structures (pits and bumps) on multilayer mirrors were investigated by our Schwarzschild objective-based EUV microscope at 13.5-nm wavelength and then characterized with an atomic force microscope. Possible defect-detection limits with large field of view and moderate magnification are discussed in terms of required irradiation dose and system performance.

Juschkin, L.; Maryasov, A.; Herbert, S. [Chair for Technology of Optical Systems (TOS), RWTH Aachen University and JARA - Fundamentals of Future Information Technology, Steinbachstr. 15, 52074 Aachen (Germany); Aretz, A. [Central Facility for Electron Microscopy (GFE), RWTH Aachen University and JARA - Fundamentals of Future Information Technology, Ahornstrasse 52074 Aachen (Germany); Bergmann, K. [Fraunhofer Institute for Laser Technology, Steinbachstr. 15, 52074 Aachen (Germany); Lebert, R. [Bruker Advanced Supercon GmbH, Friedrich-Ebert-Strasse 1, 51429 Bergisch Gladbach (Germany)

2011-09-09T23:59:59.000Z

306

Tritiated Amorphous Silicon: Insights into the Staebler-Wronski Mechanism  

DOE Green Energy (OSTI)

Hydrogen, though essential for device-quality amorphous silicon, likely contributes to the light-induced degradation process (Staebler-Wronski effect) that reduces the solar cell efficiency by about 4 absolute percent. We are testing the role of hydrogen by using its isotope tritium. When tritium bonded to Si spontaneously decays into inert helium-3, it should leave behind the Si dangling bond defect. We have studied degradation due to tritium and note its resemblance to the Staebler-Wronski effect. Surprisingly, 100x fewer defects are created than expected from the tritium decay rate, suggesting a mechanism that heals most of the defects, even at temperatures down to 4 K. We consider different mechanisms for the thermal and athermal healing processes (e.g. motion of hydrogen, effect of beta-electrons, decay of hydrogen-tritium molecules). Our findings shed new light on the degradation mechanism in a Si:H and help reveal the role of hydrogen and structural rearrangements near a newly created defect.

Stradins, P.; Branz, H. M.; Whitaker, J.; Viner, J.; Taylor, P. C.; Johnson, E.; Kherani, N.; Zukotynski, S.

2005-01-01T23:59:59.000Z

307

Mechanical Design  

SciTech Connect

The particle beam of the SXR (soft x-ray) beam line in the LCLS (Linac Coherent Light Source) has a high intensity in order to penetrate through samples at the atomic level. However, the intensity is so high that many experiments fail because of severe damage. To correct this issue, attenuators are put into the beam line to reduce this intensity to a level suitable for experimentation. Attenuation is defined as 'the gradual loss in intensity of any flux through a medium' by [1]. It is found that Beryllium and Boron Carbide can survive the intensity of the beam. At very thin films, both of these materials work very well as filters for reducing the beam intensity. Using a total of 12 filters, the first 9 being made of Beryllium and the rest made of Boron Carbide, the beam's energy range of photons can be attenuated between 800 eV and 9000 eV. The design of the filters allows attenuation for different beam intensities so that experiments can obtain different intensities from the beam if desired. The step of attenuation varies, but is relative to the thickness of the filter as a power function of 2. A relationship for this is f(n) = x{sub 0}2{sup n} where n is the step of attenuation desired and x{sub 0} is the initial thickness of the material. To allow for this desired variation, a mechanism must be designed within the test chamber. This is visualized using a 3D computer aided design modeling tool known as Solid Edge.

2010-08-25T23:59:59.000Z

308

PREDICTING TEMPERATURE BEHAVIOR IN CARBONATE ACIDIZING TREATMENTS  

E-Print Network (OSTI)

To increase the successful rate of acid stimulation, a method is required to diagnose the effectiveness of stimulation which will help us to improve stimulation design and decide whether future action, such as diversion, is needed. For this purpose, it is important to know how much acid enters each layer in a multilayer carbonate formation and if the low-permeability layer is treated well. This work develops a numerical model to determine the temperature behavior for both injection and flow-back situations. An important phenomenon in this process is the heat generated by reaction, affecting the temperature behavior significantly. The result of the thermal model showed significant temperature effects caused by reaction, providing a mechanism to quantitatively determine the acid flow profile. Based on this mechanism, a further inverse model can be developed to determine the acid distribution in each layer.

Tan, Xuehao

2009-05-01T23:59:59.000Z

309

Power-Law Distributions in Circulating Money: Effect of Preferential Behavior  

E-Print Network (OSTI)

We introduce preferential behavior into the study on statistical mechanics of money circulation. The computer simulation results show that the preferential behavior can lead to power laws on distributions over both holding time and amount of money held by agents. However, some constraints are needed in generation mechanism to ensure the robustness of power-law distributions.

Ding, N; Ding, Ning; Wang, Yougui

2005-01-01T23:59:59.000Z

310

Defect microstructural evolution in ion irradiated metallic nanofoils: Kinetic Monte Carlo simulation versus cluster dynamics modeling and in situ transmission electron microscopy experiments  

SciTech Connect

Understanding materials degradation under intense irradiation is important for the development of next generation nuclear power plants. Here we demonstrate that defect microstructural evolution in molybdenum nanofoils in situ irradiated and observed on a transmission electron microscope can be reproduced with high fidelity using an object kinetic Monte Carlo (OKMC) simulation technique. Main characteristics of defect evolution predicted by OKMC, namely, defect density and size distribution as functions of foil thickness, ion fluence and flux, are in excellent agreement with those obtained from the in situ experiments and from previous continuum-based cluster dynamics modeling. The combination of advanced in situ experiments and high performance computer simulation/modeling is a unique tool to validate physical assumptions/mechanisms regarding materials response to irradiation, and to achieve the predictive power for materials stability and safety in nuclear facilities.

Xu Donghua; Wirth, Brian D. [Department of Nuclear Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States); Li Meimei [Division of Nuclear Engineering, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Kirk, Marquis A. [Division of Materials Science, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2012-09-03T23:59:59.000Z

311

The Graphene/Graphane Interface Energy and Implications for Defects  

Science Conference Proceedings (OSTI)

Recent theoretical work has shown that electronic properties of graphene sheets can be systematically modified by the partial hydrogenation of the sheets. Two possible perfect and distinct graphene/graphane interfaces (called zig-zag and armchair) have very different but potentially useful electronic properties which are nevertheless likely to be affected by the presence of defects. In an effort to evaluate their relative energetics and their potential for defects, the structure and energies of the zig-zag and armchair interfaces have been computed for infinite sheets of periodically alternating stripes of graphene and graphane ribbons of various widths. The presence of an interface causes significant strains in both the graphene and graphane regions, with both shear strains and area strains typically close to 1%. The associated large strain energies may lead to defects that relieve the strain but disrupt the lattice. The energies per unit length associated with the interfaces alone are approximately 0.12 eV/ for the zig-zag interface and 0.11 eV/ for the armchair. The large misfit strains and energies suggest that formation of strain-relieving defects at the interface should be highly favorable.

Averill, Frank [ORNL; Morris, James R [ORNL

2011-01-01T23:59:59.000Z

312

Defect-induced magnetism and transport phenomena in epitaxial oxides  

E-Print Network (OSTI)

observed in certain two-dimensionally conducting samples in limited temperature regimes. By optimising the (defect) structure at the interface, i.e. by introducing a single unit cell of (La0.5,Sr0.5)TiO3 or SnTiO3, it is shown that the sheet carrier density...

Schoofs, Frank

2012-07-03T23:59:59.000Z

313

Removal of Defect Clusters by Twin Boundaries in Nanotwinned ...  

Science Conference Proceedings (OSTI)

... of SFTs in irradiated nanotwinned Ag is much lower than that in its bulk counterpart. ... Characterization of Irradiation Induced Defects in T91 Steel ... Exploring Fission Enhanced Diffusion of Uranium in Uranium Dioxide Using Classical ... Ion-induced Swelling of Yttrium Oxide Dispersion-strengthened 0Cr18Ni10Ti Steel.

314

Defects and Related Phenomena I - Programmaster.org  

Science Conference Proceedings (OSTI)

Metal oxides added to UO2 to improve material performance during irradiation, ... The oxygen and uranium Frenkel pairs and the uranium-oxygen Schottky ... Using the law of mass action to the Frenkel and Schottky defects in doped UO2, ... migration in the fluorite-structured oxide CeO2 is investigated at the atomistic level.

315

Local vs. global models for effort estimation and defect prediction  

Science Conference Proceedings (OSTI)

Data miners can infer rules showing how to improve either (a) the effort estimates of a project or (b) the defect predictions of a software module. Such studies often exhibit conclusion instability regarding what is the most effective action for different ...

Tim Menzies; Andrew Butcher; Andrian Marcus; Thomas Zimmermann; David Cok

2011-11-01T23:59:59.000Z

316

Convergence properties of the local defect correction method for parabolic  

E-Print Network (OSTI)

Convergence properties of the local defect correction method for parabolic problems R. Minero , H for parabolic problems presented in [14]. We derive a general expression for the iteration matrix of the method, domain decomposition and regridding. In [14] LDC is generalized to solve parabolic partial differential

Eindhoven, Technische Universiteit

317

Defects detection of cylindrical object's surface using vision system  

Science Conference Proceedings (OSTI)

This research is aimed to accomplish an automatic visual inspection for the lateral surface of cylindrical objects using cameras and image processing technique. In this paper, the main concern is on the hardware tools that are needed to test the defects ... Keywords: conical mirror, image processing in MATLAB, line scan camera, matrix camera, multiple flat mirrors

M. Ali; M. Mailah; S. Kazi; H. H. Tang

2011-12-01T23:59:59.000Z

318

Neurobiology of Bat Vocal Behavior  

E-Print Network (OSTI)

Vocal plasticity is presumed to be a key element underlying the evolution of human speech and language, but the mechanisms and neuroanatomical basis for this plasticity remain largely unknown. The Mexican free-tailed bat, Tadarida brasiliensis, presents a unique opportunity to advance our understanding of the evolution and neurobiology of mammalian vocal communication because this animal displays elements of vocal complexity and plasticity that are more sophisticated than any mammal other than humans, including non-human primates. Current models of vocal control in mammals do not account for the vocal complexity of free-tailed bats. The purpose of this dissertation is to fill that gap in knowledge by identifying a possible neuronal basis for vocal complexity in free-tailed bats. This will be achieved by 1) providing a detailed analysis of the free-tailed bats vocal behaviors, 2) mapping the distribution of neurotransmitter receptor types suspected of involvement in vocal control, 3) identifying brain regions that exhibit increased neuronal activity during vocalizing, and 4) pharmacologically manipulating putative vocal control regions to confirm and characterize their function in vocalizing. Analysis of Tadaridas vocal behavior indicated that they have a vast vocal repertoire, including many different call types, context-dependent sensory-feedback driven vocal plasticity, and syntactically-organized stereotyped songs. Their vocal behavior changed seasonally, so I mapped the distribution of melatonin binding sites in the brain, finding high densities in the striatum, similar to dopamine receptor distribution. I then used immunohistochemical labeling of the immediate early gene cfos to map neuronal activation in brains of highly vocal bats to find ROIs activated by vocal production. This technique not only identified all previously known regions of the mammalian vocal motor pathway but also revealed activity in novel brain regions that could potentially account for vocal plasticity, including a localized region of the basal ganglia, the dorsolateral caudate nucleus, and the anterior cingulate region of the frontal cortex. Pharmacological excitation of these regions evoked complex vocal sequences similar to the songs recorded in the field and lab. These results support the hypothesis that the mammalian basal ganglia may play a crucial role in the plasticity and complexity of mammalian vocal behaviors.

Schwartz, Christine Patrice

2010-12-01T23:59:59.000Z

319

Physicalism versus quantum mechanics  

E-Print Network (OSTI)

Foundations of Quantum Mechanics. (Princeton UniversityMind, Matter, and Quantum Mechanics, (Springer, Berlin & NewMindful Universe: Quantum Mechanics and the Participating

Stapp, Henry P; Theoretical Physics Group; Physics Division

2009-01-01T23:59:59.000Z

320

Automatic target defect identification for TFT-LCD array process inspection using kernel FCM-based fuzzy SVDD ensemble  

Science Conference Proceedings (OSTI)

Inline defect inspection plays a critical role in yield improvement for thin film transistor liquid crystal display (TFT-LCD) manufacturing. In array process, some defects are critical to the quality of LCD panels (target defects), while some are not ... Keywords: Fuzzy c-means (FCM), Inline defect inspection, Support vector data description (SVDD), Support vector machine (SVM), TFT-LCD, Target defect identification

Yi-Hung Liu; Szu-Hsien Lin; Yi-Ling Hsueh; Ming-Jiu Lee

2009-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Applications of Admittance Spectroscopy in Photovoltaic Devices Beyond Majority Carrier Trapping Defects: Preprint  

DOE Green Energy (OSTI)

Admittance spectroscopy is commonly used to characterize majority-carrier trapping defects. In today's practical photovoltaic devices, however, a number of other physical mechanisms may contribute to the admittance measurement and interfere with the data interpretation. Such challenges arise due to the violation of basic assumptions of conventional admittance spectroscopy such as single-junction, ohmic contact, highly conductive absorbers, and measurement in reverse bias. We exploit such violations to devise admittance spectroscopy-based methods for studying the respective origins of 'interference': majority-carrier mobility, non-ohmic contact potential barrier, minority-carrier inversion at hetero-interface, and minority-carrier lifetime in a device environment. These methods are applied to a variety of photovoltaic technologies: CdTe, Cu(In,Ga)Se2, Si HIT cells, and organic photovoltaic materials.

Li, J. V.; Crandall, R. S.; Repins, I. L.; Nardes, A. M.; Levi, D. H.; Sulima, O.

2011-07-01T23:59:59.000Z

322

Defects and Polytypism in SiC: The Role of Diffuse X-Ray Scattering  

Science Conference Proceedings (OSTI)

Stacking faults (SFs) and the 3C-6H polytypic transition in thick (001)-oriented 3C-SiC crystals are studied by means of diffuse X-ray scattering. The presence of SFs lying in the {l_brace}111{r_brace} planes gives rise to streaked reciprocal lattice points with the streaks being parallel to the directions. In the case of low SF densities the defects are uncorrelated and the simulation of the diffuse intensity distribution allows to derive the SF density. In partially transformed crystals, the SFs are spatially correlated which gives rise to an intense and asymmetric diffuse scattering distribution. Its simulation allows to determine both the transformation mechanism and the transformation level.

Boulle, A.; Dompoint, D. [Science des Procedes Ceramiques et de Traitements de surface (SPCTS-CNRS UMR 6638), ENSCI 47 avenue Albert Thomas 87065 Limoges Cedex (France); Galben-Sandulache, I.; Chaussende, D. [Laboratoires des Materiaux et du Genie Physique (LMGP-CNRS UMR 5628), Grenoble INP, Minatec 3 parvis Louis Neel, BP 257, 38016 Grenoble Cedex 01 (France)

2010-11-01T23:59:59.000Z

323

2.001 Mechanics & Materials I, Spring 2003  

E-Print Network (OSTI)

Introduction to statics and the mechanics of deformable solids. Emphasis on the three basic principles of equilibrium, geometric compatibility, and material behavior. Stress and its relation to force and moment; strain and ...

Sarma, Sanjay E.

324

Microscopic origins of metastable effects in a-Si:H and deep defect characterization in a-Si,Ge:H alloys. Annual subcontract report, 1 February 1991--31 January 1992  

DOE Green Energy (OSTI)

This report describes works to use transient photocapacitance and photocurrent measurements to determine the deep defect distribution and processes in low-band-gap a-Si,Ge:H alloys. Samples for these studies were produced by the photochemical vapor deposition (photo-CVD) growth method and were obtained through a collaboration with researchers at the University of Delaware. This report discusses how a detailed comparison between the photocapacitance and photocurrent spectra can be used to separately examine the majority and minority carrier processes. The results are as follows: (1) The midgap defect densities in the alloy regime near 1.3 eV can be as low as 5 {times} 10{sup 16} cm{sup {minus}3} in such photo-CVD samples. (2) There exists a second defect band roughly 0.4 eV below E{sub c} of a similar magnitude to the midgap defect density that exhibits significant lattice relaxation behavior in its electron trapping dynamics. (3) The hole {mu}{tau} products determined for the lowest defect sample are roughly 5 {times} 10{sup {minus}10} cm{sup 2}/V, comparable with the highest hole {mu}{tau} products reported in sandwich geometry measurements for alloys in this composition range. (4) The hole {mu}{tau} is found to be roughly inversely proportional to the midgap defect density for the samples studied. This is consistent with the fact that the effective minority carrier lifetime for such measurements is limited by the deep state trapping time.

Cohen, J.D. [Oregon Univ., Eugene, OR (United States)

1992-07-01T23:59:59.000Z

325

Is Quantum Mechanics needed to explain consciousness ?  

E-Print Network (OSTI)

In this short comment to a recent contribution by E. Manousakis [1] it is argued that the reported agreement between the measured time evolution of conscious states during binocular rivalry and predictions derived from quantum mechanical formalisms does not require any direct effect of QM. The recursive consumption analysis process in the Ouroboros Model can yield the same behavior.

Knud Thomsen

2007-11-13T23:59:59.000Z

326

Migration Mechanisms of Oxygen Interstitial Clusters in UO2  

Science Conference Proceedings (OSTI)

Understanding the migration kinetics of radiation-induced point defects and defect clusters is a key to predicting the microstructural evolution and mass transport in nuclear fuels. Although the diffusion kinetics of point defects in UO2 is well explored both experimentally and theoretically, the kinetics of defect clusters is not well understood. In this work the migration mechanisms of oxygen interstitial clusters of size one to five atoms (1Oi 5Oi) in UO2 are investigated by temperature-accelerated dynamics simulations without any a priori assumptions of migration mechanisms. It is found that the migration paths of oxygen interstitial clusters are complex and non-intuitive and that multiple migration paths and barriers exist for some clusters. It is also found that the cluster migration barrier does not increase with increasing cluster size and its magnitude has the following order: 2Oi < 3Oi < 1Oi < 5Oi < 4Oi. Possible finite-size effects are checked with three different sized systems. The results show good agreement with other available experimental and theoretical data. In particular, the relatively large migration barriers of cuboctahedral clusters (4Oi and 5Oi) are in good agreement with the experimentally measured oxygen diffusion activation energy in U4O9, which is thought to contain many such clusters. The cluster migration sequence may explain the interesting relationship between the oxygen diffusivity and stoichiometry in UO2+x.

Xian-Ming Bai; Anter El-Azab; Jianguo Yu; Todd R. Allen

2013-01-01T23:59:59.000Z

327

First-Principles Study of Point Defects in LaAlO?  

E-Print Network (OSTI)

In this study, the native point defects including oxygen vacancy and interstitial, metal (La, Al) vacancy and interstitial, and metal antisite in perovskite LAO are studied. Defect formation energies are studied as a ...

Zheng, J.X.

328

Single Cell Mechanics BIOMATERIALS  

E-Print Network (OSTI)

Single Cell Mechanics BIOMATERIALS Our goal is to develop fundamental tools to measure the response of live cells to mechanical stimulation. The mechanisms by which cells convert mechanical forces evaluate the underlying mechanisms of cell mechanics. Objective Impact and Customers · Cancer, heart

329

Performance Limitations of mc-Si Solar Cells Caused by Defect Clusters: Preprint  

DOE Green Energy (OSTI)

This paper presents a combination of numerical and experimental methods used to characterize defect clusters in multicrystalline silicon solar cells.

Sopori, B.; Rupnowski, P.; Mehta, V.; Budhraja, V.; Johnston, S.; Call, N.; Moutinho, H.; Al-Jassim, M.; Shaikh, A /; Seacrist, M.; Carlson, D.

2009-02-01T23:59:59.000Z

330

Relativistic mechanism of superconductivity  

E-Print Network (OSTI)

According to the theory of relativity, the relativistic Coulomb's force between an electron pair is composed of two parts, the main part is repulsive, while the rest part can be attractive in certain situations. Thus the relativistic attraction of an electron pair provides an insight into the mechanism of superconductivity. In superconductor, there are, probably at least, two kinds of collective motions which can eliminate the repulsion between two electrons and let the attraction being dominant, the first is the combination of lattice and electron gas, accounting for traditional superconductivity; the second is the electron gas themselves, accounting for high $T_c$ superconductivity. In usual materials, there is a good balance between the repulsion and attraction of an electron pair, the electrons are regarded as free electrons so that Fermi gas theory plays very well. But in some materials, when the repulsion dominates electron pairs, the electron gas will has a behavior opposite to superconductivity. In the present paper the superconducting states are discussed in terms of relativistic quantum theory in details, some significant results are obtained including quantized magnetic flux, London equation, Meissner effect and Josephson effect.

H. Y. Cui

2002-12-17T23:59:59.000Z

331

Defect Based Spin Mediation in Delta-Phase Plutonium  

Science Conference Proceedings (OSTI)

We earlier reported the measured decrease of electrical resistivity during isochronal-annealing of ion irradiation damage that was accumulated at low-temperature (10 or 20K), and the temperature dependence of the resistance of defect-populations produced by low-temperature damage-accumulation and annealing in a stabilized {delta}-phase plutonium alloy, Pu(3.3 at%Ga)[1]. We noted that the temperature dependence of the resistance of defects resulting from low-temperature damage accumulation and subsequent annealing exhibits a -ln(T) temperature dependence suggestive of a Kondo impurity. A discussion of a possible ''structure-property'' effect, as it might relate to the nature of the {delta}-phase of Pu, is presented.

Fluss, M J; Wirth, B D; Wall, M; Felter, T E; Caturla, M J; Kubota, A; Diaz de la Rubia, T

2003-11-19T23:59:59.000Z

332

Analysis of defects at the interface between high-k thin films and (100) silicon  

Science Conference Proceedings (OSTI)

Paramagnetic defects in atomic layer deposition grown aluminium oxide thin films have been studied using electron paramagnetic resonance. Initial spectra indicate the presence of Si-db, P"b"0 and P"b"1 defects, previously observed in Si/SiO"2 structures. ... Keywords: Aluminium oxide, Defects, EPR, High-k, Interfaces, Thin films

B. J. Jones; R. C. Barklie

2005-06-01T23:59:59.000Z

333

Fault Modeling and Analysis for Resistive Bridging Defects in a Synchronizer  

Science Conference Proceedings (OSTI)

This paper presents fault modeling and analysis for bridging defects in a synchronizer that is implemented by two D flip-flops. Bridging defects are injected into any two nodes of the synchronizer, and HSPICE is used to perform circuit analysis. The ... Keywords: Bridging defect, Fault modeling, Synchronizer

Hyoung-Kook Kim; Wen-Ben Jone; Laung-Terng Wang

2010-06-01T23:59:59.000Z

334

Chromatin dynamics: Nucleosomes go mobile through twist defects  

E-Print Network (OSTI)

We study the spontaneous ''sliding'' of histone spools (nucleosomes) along DNA as a result of thermally activated single base pair twist defects. To this end we map the system onto a suitably extended Frenkel-Kontorova model. Combining results from several recent experiments we are able to estimate the nucleosome mobility without adjustable parameters. Our model shows also how the local mobility is intimately linked to the underlying base pair sequence.

I. M. Kulic; H. Schiessel

2003-02-10T23:59:59.000Z

335

Bohmian Mechanics and Quantum Information  

E-Print Network (OSTI)

Many recent results suggest that quantum theory is about information, and that quantum theory is best understood as arising from principles concerning information and information processing. At the same time, by far the simplest version of quantum mechanics, Bohmian mechanics, is concerned, not with information but with the behavior of an objective microscopic reality given by particles and their positions. What I would like to do here is to examine whether, and to what extent, the importance of information, observation, and the like in quantum theory can be understood from a Bohmian perspective. I would like to explore the hypothesis that the idea that information plays a special role in physics naturally emerges in a Bohmian universe.

Sheldon Goldstein

2009-07-14T23:59:59.000Z

336

Understanding the defect structure of solution grown zinc oxide  

Science Conference Proceedings (OSTI)

Zinc oxide (ZnO) is a wide bandgap semiconducting oxide with many potential applications in various optoelectronic devices such as light emitting diodes (LEDs) and field effect transistors (FETs). Much effort has been made to understand the ZnO structure and its defects. However, one major issue in determining whether it is Zn or O deficiency that provides ZnO its unique properties remains. X-ray absorption spectroscopy (XAS) is an ideal, atom specific characterization technique that is able to probe defect structure in many materials, including ZnO. In this paper, comparative studies of bulk and aqueous solution grown ({lighting and other optoelectronic device applications. - Graphical abstract: Highlights: Black-Right-Pointing-Pointer ZnO powders have been synthesized through an aqueous solution method. Black-Right-Pointing-Pointer Defect structure studied using XAS and XPDF. Black-Right-Pointing-Pointer Zn-Zn correlations are less in the ZnO powders synthesized in solution than bulk. Black-Right-Pointing-Pointer Zn vacancies are present in the powders synthesized. Black-Right-Pointing-Pointer EXAFS and XPDF, when used complementary, are useful characterization techniques.

Liew, Laura-Lynn [Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A-STAR), 3 Research Link, Singapore 117602 (Singapore); School of Materials Science and Engineering, Nanyang Technological University, Block N4.1 Nanyang Avenue, Singapore 639798 (Singapore); Sankar, Gopinathan, E-mail: g.sankar@ucl.ac.uk [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Handoko, Albertus D. [Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A-STAR), 3 Research Link, Singapore 117602 (Singapore); Goh, Gregory K.L., E-mail: g-goh@imre.a-star.edu.sg [Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A-STAR), 3 Research Link, Singapore 117602 (Singapore); School of Materials Science and Engineering, Nanyang Technological University, Block N4.1 Nanyang Avenue, Singapore 639798 (Singapore); Kohara, Shinji [Japan Synchrotron Radiation Research Institute (JASRI), Mikazuki, Sayo, Hyogo 679-5198 (Japan)

2012-05-15T23:59:59.000Z

337

The Behavior of Lakes  

NLE Websites -- All DOE Office Websites (Extended Search)

Behavior of Lakes Behavior of Lakes Nature Bulletin No, 320-A November 9, 1968 Forest Preserve District of Cook County Richard B. Ogilvie, President Roland F. Eisenbeis, Supt. of Conservation THE BEHAVIOR OF LAKES In many ways lakes are like living things -- especially a tree. A lake breathes and has a circulation; it is warmed and fed; it harbors many other living things; and in cold weather it goes into a winter sleep. If it were not for the special character of a body of standing water which we call a lake, the things that live in it would be radically different or, perhaps, not exist at all. Water is a very strange substance in many ways. For example, it is remarkable because it expands, becomes lighter and floats when it freezes into ice. If, like most substances, water shrank when it changed from a liquid to a solid, it would sink. Then, ponds and lakes would freeze from the bottom up and become solid blocks of ice. This would make life impossible for most kinds of aquatic plants and animals and indirectly affect all living things. Further, water is a poor conductor of heat -- otherwise lakes would freeze much deeper and, again most living things in it would perish.

338

Fourth workshop on the role of point defects/defect complexes in silicon device processing. Summary report  

DOE Green Energy (OSTI)

The 4th Point Defect Workshop was aimed at reviewing recent new understanding of the defect engineering techniques that can improve the performance of solar cells fabricated on low-cost silicon substrates. The theme of the workshop was to identify approaches that can lead to 18% commercial silicon solar cells in the near future. These approaches also define the research tasks for the forthcoming new DOE/NREL silicon materials research program. It was a consensus of the workshop attendees that the goal of 18%-efficient multicrystalline silicon solar cells is right on target, and the payoff for the investment by DOE will manifest itself in the next few years as reduced costs for high-efficiency cell fabrication.

Tan, T.; Jastrzebski, L.; Sopori, B.

1994-07-01T23:59:59.000Z

339

Four-dimensional understanding of quantum mechanics  

E-Print Network (OSTI)

In this paper I will try to convince that quantum mechanics does not have to lead to indeterminism, but is just a natural consequence of four-dimensional nature of our world - that for example particles shouldn't be imagined as 'moving points' in space, but as their trajectories in the spacetime like in optimizing action formulation of Lagrangian mechanics. There will be analyzed simplified model - Boltzmann distribution among trajectories occurs to give quantum mechanic like behavior - for example electron moving in proton's potential would make some concrete trajectory which average exactly to the probability distribution of the quantum mechanical ground state. We will use this model to build intuition about quantum mechanics and discuss its generalizations to get some effective approximation of physics. We will see that topological excitations of the simplest model obtained this way already creates known from physics particle structure, their decay modes and electromagnetic/gravitational interactions between them.

Jarek Duda

2009-10-14T23:59:59.000Z

340

The effect of slightly faster strain rates and internal hydrogen on uranium-0. 8 weight percent titanium alloy mechanical properties  

DOE Green Energy (OSTI)

Mechanical testing of uranium-0.8 wt % titanium (U-0.8 wt % Ti) alloys can affect the outcome of mechanical properties, primarily ductility, by varying the crosshead velocity, which changes the strain rate. However, most specifications that govern mechanical properties of this alloy reference ASTM E-8, which limits the speed to 0.5 in./in. of gage length per minute. Our current procedure for testing U-0.8 Ti is not at the maximum speed permitted in ASTM E-8, so an experiment was designed to evaluate the effect of maximizing the crosshead velocity per ASTM E-8. In order to create a fair assessment, tensile specimens were prepared that were low in internal hydrogen (0.02 ppM) and higher in internal hydrogen (0.36 ppM). External hydrogen effects were minimized by testing in a controlled environment that contained less than 10% relative humidity. Test results showed that for the low hydrogen test group, increasing the crosshead velocity caused a significant increase in reduction in area (RA), but not in elongation. For the higher hydrogen test group, increasing the speed resulted in a significant increase in RA and an increase, though not statistically significant, in elongation. Of equal importance was an observation that strongly suggests a correlation between material defects, like inclusion clusters, and higher hydrogen content, especially at the slower strain rate that would explain the erratic behavior in ductile properties associated with this alloy. As a result of this study, increasing the crosshead velocity to 0.32 in./min is recommended for mechanical testing of U-0.8 Ti alloys. 9 refs., 4 figs., 5 tabs.

Bird, E.L.

1990-10-10T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Impact of Defect Creation and Motion on the Thermodynamics and Large-Scale Reorganization of Self-Assembled Clathrin Lattices  

SciTech Connect

We develop a theoretical model for the thermodynamics and kinetics of clathrin self-assembly. Our model addresses the behavior in two dimensions and can be easily extended to three dimensions, facilitating the study of membrane, surface, and bulk assembly. The clathrin triskelia are modeled as flexible pinwheels that form leg-leg associations and resist bending and stretching deformations. Thus, the pinwheels are capable of forming a range of ring structures, including 5-, 6-, and 7-member rings that are observed experimentally. Our theoretical model employs Brownian dynamics to track the motion of clathrin pinwheels at sufficiently long time scales to achieve complete assembly. Invoking theories of dislocation-mediated melting in two dimensions, we discuss the phase behavior for clathrin self-assembly as predicted by our theoretical model. We demonstrate that the generation of 5-7 defects in an otherwise perfect honeycomb lattice resembles creation of two dislocations with equal and opposite Burgers vectors. We use orientational- and translational-order correlation functions to predict the crystalline-hexatic and hexatic-liquid phase transitions in clathrin lattices. These results illustrate the pivotal role that molecular elasticity plays in the physical behavior of self-assembling and self-healing materials.

Mehraeen, Shafigh

2011-11-04T23:59:59.000Z

342

MechanicalTesting  

NLE Websites -- All DOE Office Websites (Extended Search)

structures, validation of encapsulant cure stress models, development of frac- ture mechanics tests for use in adhesion studies and understanding the failure mechanism of...

343

Wave Mechanics without Probability  

E-Print Network (OSTI)

The behavior of monochromatic electromagnetic waves in stationary media is shown to be ruled by a frequency dependent function, which we call Wave Potential, encoded in the structure of the Helmholtz equation. Contrary to the common belief that the very concept of "ray trajectory" is reserved to the eikonal approximation, a general and exact ray-based Hamiltonian treatment, reducing to the eikonal approximation in the absence of Wave Potential, shows that its presence induces a mutual, perpendicular ray-coupling, which is the one and only cause of any typically wave-like phenomenon, such as diffraction and interference. Recalling, then, that the time-independent Schroedinger and Klein-Gordon equations (associating stationary "matter waves" to mono-energetic particles) are themselves Helmholtz-like equations, the exact, ray-based treatment developed for classical electromagnetic waves is extended - without resorting to statistical concepts - to the exact, trajectory-based Hamiltonian dynamics of mono-energetic point-like particles, both in the non-relativistic and in the relativistic case. The trajectories turn out to be perpendicularly coupled, once more, by an exact, stationary, energy-dependent Wave Potential, coinciding in the form, but not in the physical meaning, with the statistical, time-varying, energy-independent "Quantum Potential" of Bohm's theory, which views particles, just like the standard Copenhagen interpretation, as traveling wave-packets. These results, together with the connection which is shown to exist between Wave Potential and Uncertainty Principle, suggest a novel, non-probabilistic interpretation of Wave Mechanics.

Adriano Orefice; Raffaele Giovanelli; Domenico Ditto

2013-02-18T23:59:59.000Z

344

Defects in germanium: new results and novel methods  

DOE Green Energy (OSTI)

Recent results obtained from quenching experiments, electron, gamma-ray, neutron and proton irradiation of germanium are reviewed. Major emphasis is given to the introduction of novel techniques for the study of shallow and deep levels. Explicitly introduced are Photothermal Ionization Spectroscopy (also called Photoelectric Spectroscopy), Deep level Transient Spectroscopy and High-Q Electron Paramagnetic Resonance. Using as examples the recently discovered hydrogen-related centers and the lithium/lithium-oxygen system in germanium it is shown that a combination of techniques can yield information on composition and structure of defects.

Haller, E.E.

1979-09-01T23:59:59.000Z

345

Preshot Predictions for Defect Induced Mix (DIME) Capsules  

SciTech Connect

In this memo, we evaluate the most probable yield and other results for the Defect Induced Mix (DIME-12A) Polar Direct Drive (PDD) capsule-only shots. We evaluate the expected yield, bang time, burn averaged ion temperature, and the average electron temperature of the Ge line-emitting region. We also include synthetic images of the capsule backlit by Cu K-{alpha} emission (8.39 keV) and core self-emission synthetic images. This memo is a companion to the maximum credible yield memo (LA-UR-12-00287) published earlier.

Bradley, Paul A. [Los Alamos National Laboratory; Krasheninnikova, Natalia S. [Los Alamos National Laboratory; Tregillis, Ian L. [Los Alamos National Laboratory; Schmitt, Mark J. [Los Alamos National Laboratory

2012-07-31T23:59:59.000Z

346

Constraint on the (GUT) symmetry breaking scale and topological defects  

Science Conference Proceedings (OSTI)

In F-term supergravity inflation models, scalar fields other than the inflaton generically receive a Hubble induced mass, which may restore gauge symmetries during inflation and phase transitions may occur during or after inflation as the Hubble parameter decreases. We study topological defect formation associated with such a phase transition in chaotic inflation in supergravity and obtain a severe constraint on the symmetry breaking scale which is related with the tensor-to-scalar ratio. This talk is based on the paper [1].

Kamada, Kohei; Nakayama, Kazunori; Yokoyama, Jun'ichi [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, D-22607 Hamburg (Germany); Department of Physics, Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan); Research Center for the Early Universe (RESCEU), Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan) and Kavli institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba, 277-8568 (Japan)

2012-07-27T23:59:59.000Z

347

Blade reliability collaborative : collection of defect, damage and repair data.  

SciTech Connect

The Blade Reliability Collaborative (BRC) was started by the Wind Energy Technologies Department of Sandia National Laboratories and DOE in 2010 with the goal of gaining insight into planned and unplanned O&M issues associated with wind turbine blades. A significant part of BRC is the Blade Defect, Damage and Repair Survey task, which will gather data from blade manufacturers, service companies, operators and prior studies to determine details about the largest sources of blade unreliability. This report summarizes the initial findings from this work.

Ashwill, Thomas D.; Ogilvie, Alistair B.; Paquette, Joshua A.

2013-04-01T23:59:59.000Z

348

Mechanism of pressure welding  

SciTech Connect

Thesis. The mechanism in polycrystalline aluminum, copper, silver, and gold was investigated. (19 figures) (DLC)

Mohamed, H.A.E.F.

1973-12-01T23:59:59.000Z

349

CARTESIAN MECHANICS* Sophie Roux  

E-Print Network (OSTI)

1 CARTESIAN MECHANICS* Sophie Roux (Centre Alexandre Koyré, EHESS, Paris) Introduction For many the search for a mathematical treatment of phenomena, on the other hand the demand for mechanical as the typical mechanical philosopher, and contrasted as such to the founder of mechanics as a science, namely

Paris-Sud XI, Université de

350

INTRODUCTION TO THE MECHANICS  

E-Print Network (OSTI)

INTRODUCTION TO THE MECHANICS OF A CONTINUOUS MEDIUM Lawrence E. Malvern Professor of Mechanics princi- ples common to all branches of solid and fluid mechanics, designed to appeal to the intuition science. The book arose from the need to provide a general preparation in contin- uum mechanics

Kaminski, Edouard

351

Graduate quantum mechanics reform  

Science Conference Proceedings (OSTI)

We address four main areas in which graduatequantum mechanics education can be improved: course content

L. D. Carr; S. B. McKagan

2009-01-01T23:59:59.000Z

352

Fatigue-crack propagation behavior of Inconel 718  

DOE Green Energy (OSTI)

The techniques of linear-elastic fracture mechanics were used to characterize the effect of several variables (temperature, environment, cyclic frequency, stress ratio, and heat-treatment variations) upon the fatigue-crack growth behavior of Inconel 718 base metal and weldments. Relevant crack growth data on this alloy from other laboratories is also presented. (33 fig, 39 references) (auth)

James, L.A.

1975-09-01T23:59:59.000Z

353

Defect Prevention and Detection in Software for Automated Test Equipment  

SciTech Connect

Software for automated test equipment can be tedious and monotonous making it just as error-prone as other software. Active defect prevention and detection are also important for test applications. Incomplete or unclear requirements, a cryptic syntax used for some test applicationsespecially script-based test sets, variability in syntax or structure, and changing requirements are among the problems encountered in one tester. Such problems are common to all software but can be particularly problematic in test equipment software intended to test another product. Each of these issues increases the probability of error injection during test application development. This report describes a test application development tool designed to address these issues and others for a particular piece of test equipment. By addressing these problems in the development environment, the tool has powerful built-in defect prevention and detection capabilities. Regular expressions are widely used in the development tool as a means of formally defining test equipment requirements for the test application and verifying conformance to those requirements. A novel means of using regular expressions to perform range checking was developed. A reduction in rework and increased productivity are the results. These capabilities are described along with lessons learned and their applicability to other test equipment software. The test application development tool, or application builder, is known as the PT3800 AM Creation, Revision and Archiving Tool (PACRAT).

E. Bean

2006-11-30T23:59:59.000Z

354

Defective graphene as promising anode material for Na-ion battery and Ca-ion battery  

E-Print Network (OSTI)

We have investigated adsorption of Na and Ca on graphene with divacancy (DV) and Stone-Wales (SW) defect. Our results show that adsorption is not possible on pristine graphene. However, their adsorption on defective sheet is energetically favorable. The enhanced adsorption can be attributed to the increased charge transfer between adatoms and underlying defective sheet. With the increase in defect density until certain possible limit, maximum percentage of adsorption also increases giving higher battery capacity. For maximum possible DV defect, we can achieve maximum capacity of 1459 mAh/g for Na-ion batteries (NIBs) and 2900 mAh/g for Ca-ion batteries (CIBs). For graphene full of SW defect, we find the maximum capacity of NIBs and CIBs is around 1071 mAh/g and 2142 mAh/g respectively. Our results will help create better anode materials with much higher capacity and better cycling performance for NIBs and CIBs.

Datta, Dibakar; Shenoy, Vivek B

2013-01-01T23:59:59.000Z

355

Characteristics of syntactic processing : an examination utilizing behavioral and fMRI techniques  

E-Print Network (OSTI)

This thesis explores two important factors that constrain the syntactic parser of the sentence processing mechanism, syntactic storage costs and plausibility information. It uses behavioral methods to explore the characteristics ...

Chen, Evan, 1975-

2004-01-01T23:59:59.000Z

356

Black Hole Thermodynamics and Statistical Mechanics  

E-Print Network (OSTI)

We have known for more than thirty years that black holes behave as thermodynamic systems, radiating as black bodies with characteristic temperatures and entropies. This behavior is not only interesting in its own right; it could also, through a statistical mechanical description, cast light on some of the deep problems of quantizing gravity. In these lectures, I review what we currently know about black hole thermodynamics and statistical mechanics, suggest a rather speculative "universal" characterization of the underlying states, and describe some key open questions.

Steven Carlip

2008-07-28T23:59:59.000Z

357

Philosophy of mind and the problem of free will in the light of quantum mechanics  

E-Print Network (OSTI)

Defects occasioned by the advent of quantum mechanics are described in detail of recent arguments by John Searle and by Jaegwon Kim pertaining to the question of the complete reducibility to the physical of the apparent capacity of a person's conscious thoughts to affect the behaviour of that person's physically described brain.

Henry P. Stapp

2008-05-01T23:59:59.000Z

358

Philosophy of Mind and the Problem of FreeWill in the Light of Quantum Mechanics.  

Science Conference Proceedings (OSTI)

Arguments pertaining to the mind-brain connection and to the physical effectiveness of our conscious choices have been presented in two recent books, one by John Searle, the other by Jaegwon Kim. These arguments are examined, and it is argued that the difficulties encountered arise from a defective understanding and application of a pertinent part of contemporary science, namely quantum mechanics.

Stapp, Henry; Stapp, Henry P

2008-04-01T23:59:59.000Z

359

Multiple stalk formation as a pathway of defect-induced membrane fusion  

E-Print Network (OSTI)

We propose that the first stage of membrane fusion need not be the formation of a single stalk. Instead, we consider a scenario for defect-induced membrane fusion that proceeds cooperatively via multiple stalk formation. The defects (stalks or pores) attract each other via membrane-mediated capillary interactions that result in a condensation transition of the defects. The resulting dense phase of stalks corresponds to the so-called fusion intermediate.

D. B. Lukatsky; Daan Frenkel

2004-03-29T23:59:59.000Z

360

The self-energy of a charged particle in the presence of a topological defect distribution  

E-Print Network (OSTI)

In this work we study a charged particle in the presence of both a continuous distribution of disclinations and a continuous distribution of edge dislocations in the framework of the geometrical theory of defects. We obtain the self-energy for a single charge both in the internal and external regions of either distribution. For both distributions the result outside the defect distribution is the self-energy that a single charge experiments in the presence of a single defect.

A. M. de M. Carvalho; Fernando Moraes; Claudio Furtado

2004-01-09T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

First principles predictions of intrinsic defects in aluminum arsenide, AlAs : numerical supplement.  

SciTech Connect

This Report presents numerical tables summarizing properties of intrinsic defects in aluminum arsenide, AlAs, as computed by density functional theory. This Report serves as a numerical supplement to the results published in: P.A. Schultz, 'First principles predictions of intrinsic defects in Aluminum Arsenide, AlAs', Materials Research Society Symposia Proceedings 1370 (2011; SAND2011-2436C), and intended for use as reference tables for a defect physics package in device models.

Schultz, Peter Andrew

2012-04-01T23:59:59.000Z

362

Is there a statistical mechanics of turbulence  

SciTech Connect

The statistical-mechanical treatment of turbulence is made questionable by strong nonlinearity and strong disequilibrium that result in the creation of ordered structures imbedded in disorder. Model systems are described which may provide some hope that a compact, yet faithful, statistical description of turbulence nevertheless is possible. Some essential dynamic features of the models are captured by low-order statistical approximations despite strongly non-Gaussian behavior. 31 refs., 5 figs.

Kraichnan, R.H.; Chen, S.Y.

1988-09-01T23:59:59.000Z

363

NSLS Mechanical Tech  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanical Tech Mechanical Tech The Mechanical Technician group is supervised by Robert Scheuerer and consists of Mechanical Technicians with fabrication/machining, assembly, installation, and alignment/surveying skills. This group also serves as an interface to Central Fabrication Services when more complex or larger fabrication efforts are needed. The Mechanical Tech group is responsible for fabricating, installing, aligning, and troubleshooting the mechanical hardware used on NSLS and SDL accelerators, front ends, and User beamlines, often starting solely from Mechanical Design group drawings or CAD files. The Mechanical Tech Group is responsible for the fabrication, assembly and installation of components at the NSLS. These components include all mechanical assemblies and RF cavities. Another part of their job is to

364

Assessment of Crack in Corrosion Defects in Natural Gas Transmission Pipelines.  

E-Print Network (OSTI)

??Pipelines are one of the safest forms of transportation for oil and gas. However, pipelines may experience some defects, such as cracks, corrosion and cracks (more)

Hosseini, Seyed Aliakbar

2010-01-01T23:59:59.000Z

365

A transmission matrix for a fused pair of integrable defects in the sine-Gordon model  

E-Print Network (OSTI)

Within the quantum sine-Gordon model a transmission matrix describing the scattering of a soliton with a fused pair of integrable defects is proposed. The result is consistent with the classical picture of scattering and highlights the differences between two defects located at separated points and two defects fused at the same point. Moreover, the analysis reveals how, for certain choices of parameters, both the soliton-soliton and the lightest-breather-soliton S-matrices of the sine-Gordon model are embedded within the transmission matrix, supporting an interpretation in which defects may be regarded as soliton constituents.

E. Corrigan; C. Zambon

2010-06-04T23:59:59.000Z

366

2012 DEFECTS IN SEMICONDUCTORS GORDON RESEARCH CONFERENCE, AUGUST 12-17, 2012  

Science Conference Proceedings (OSTI)

The meeting shall strive to develop and further the fundamental understanding of defects and their roles in the structural, electronic, optical, and magnetic properties of bulk, thin film, and nanoscale semiconductors and device structures. Point and extended defects will be addressed in a broad range of electronic materials of particular current interest, including wide bandgap semiconductors, metal-oxides, carbon-based semiconductors (e.g., diamond, graphene, etc.), organic semiconductors, photovoltaic/solar cell materials, and others of similar interest. This interest includes novel defect detection/imaging techniques and advanced defect computational methods.

GLASER, EVAN

2012-08-17T23:59:59.000Z

367

Stress Management: X-Rays Reveal Si Thin-Film Defects  

Science Conference Proceedings (OSTI)

Stress Management: X-Rays Reveal Si Thin-Film Defects. ... Advanced Photon Source, and supported in part by the Department of Energy. ...

2011-04-26T23:59:59.000Z

368

Surface defects, the superconformal index and q-deformed Yang-Mills  

E-Print Network (OSTI)

Recently a prescription to compute the four-dimensional N = 2 superconformal index in the presence of certain BPS surface defects has been given. These surface defects are labelled by symmetric representations of SU(N). In the present paper we give a prescription to compute the superconformal index in the presence of surface defects labelled by arbitrary representations of SU(N). Furthermore, we extend the dictionary between the N = 2 superconformal Schur-index and correlators of q-deformed Yang-Mills to incorporate such surface defects.

Luis F. Alday; Mathew Bullimore; Martin Fluder; Lotte Hollands

2013-03-19T23:59:59.000Z

369

K2S2O8-KOH Etching System for Revealing Defects and Pattern ...  

Science Conference Proceedings (OSTI)

Accelerated Light Induced Degradation, ALID, for Monitoring of Defects in PV Silicon ... Silicon Solar Cells Evaluated by LBIC and Equivalent Circuit Model.

370

Detection of Device-Process Induced Extended Defects in 4H-SiC  

Science Conference Proceedings (OSTI)

Accelerated Light Induced Degradation, ALID, for Monitoring of Defects in PV Silicon ... Silicon Solar Cells Evaluated by LBIC and Equivalent Circuit Model.

371

The Role of Line Defects on the Conductivity of Thin-film Yttria ...  

Science Conference Proceedings (OSTI)

Presentation Title, The Role of Line Defects on the Conductivity of Thin-film Yttria- stabilized Zirconia. Author(s), Edmund Mills, Nigel Browning, Yayoi Takamura,...

372

Internal pipe attachment mechanism  

DOE Patents (OSTI)

An attachment mechanism is described for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection. 6 figures.

Bast, R.M.; Chesnut, D.A.; Henning, C.D.; Lennon, J.P.; Pastrnak, J.W.; Smith, J.A.

1994-12-13T23:59:59.000Z

373

The Department of Mechanical Engineering --Engineering Mechanics  

E-Print Network (OSTI)

, Missile, Research, Development and Engineering Directorate's Propulsion Iaborato'. Ills primaly areas of research are in numerical combustion, and the thermal and mechanical aging ofnitrate esterpropellants decomposition and combustion. Stabilizers are added to the propellants to neutralize the decomposition products

Endres. William J.

374

Ion beam collimating grid to reduce added defects  

DOE Patents (OSTI)

A collimating grid for an ion source located after the exit grid. The collimating grid collimates the ion beamlets and disallows beam spread and limits the beam divergence during transients and steady state operation. The additional exit or collimating grid prevents beam divergence during turn-on and turn-off and prevents ions from hitting the periphery of the target where there is re-deposited material or from missing the target and hitting the wall of the vessel where there is deposited material, thereby preventing defects from being deposited on a substrate to be coated. Thus, the addition of a collimating grid to an ion source ensures that the ion beam will hit and be confined to a specific target area.

Lindquist, Walter B. (Oakland, CA); Kearney, Patrick A. (Livermore, CA)

2003-01-01T23:59:59.000Z

375

Electrodes mitigating effects of defects in organic electronic devices  

DOE Patents (OSTI)

A compound electrode for organic electronic devices comprises a thin first layer of a first electrically conducting material and a second electrically conducting material disposed on the first layer. In one embodiment, the second electrically conducting material is formed into a plurality of elongated members. In another embodiment, the second material is formed into a second layer. The elongated members or the second layer has a thickness greater than that of the first layer. The second layer is separated from the first layer by a conducting material having conductivity less than at least the material of the first layer. The compound electrode is capable of mitigating adverse effects of defects, such as short circuits, in the construction of the organic electronic devices, and can be included in light-emitting or photovoltaic devices.

Heller, Christian Maria Anton (Albany, NY)

2008-05-06T23:59:59.000Z

376

Donor behavior of Sb in ZnO  

Science Conference Proceedings (OSTI)

Electrical behavior of Sb in ZnO:Sb layers doped in a wide concentration range was studied using temperature dependent Hall effect measurements. The layers were grown by plasma-enhanced molecular beam epitaxy, and the Sb concentration was changed by varying the Sb flux, resulting in electron concentrations in the range of 10{sup 16} to nearly 10{sup 20} cm{sup -3}. Upon annealing, the electron concentration increased slightly and more notable was that the electron mobility significantly improved, reaching a room-temperature value of 110 cm{sup 2}/V s and a low-temperature value of 145 cm{sup 2}/V s, close to the maximum of {approx}155 cm{sup 2}/V s set by ionized impurity scattering. Hall data and structural data suggest that Sb predominantly occupies Zn sublattice positions and acts as a shallow donor in the whole concentration range studied. In the layers with high Sb content ({approx}1 at. %), acceptor-type compensating defects (possibly Sb on oxygen sites and/or point-defect complexes involving Sb{sub O}) are formed. The increase of electron concentration with increasing oxygen pressure and the increase in ZnO:Sb lattice parameter at high Sb concentrations suggest that acceptors involving Sb{sub O} rather than Sb{sub Zn}-2V{sub Zn} complexes are responsible for the compensation of the donors.

Liu, H. Y.; Izyumskaya, N.; Avrutin, V.; Oezguer, Ue.; Morkoc, H. [Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, Virginia 23284 (United States); Yankovich, A. B.; Kvit, A. V.; Voyles, P. M. [Department of Materials Science and Engineering, University Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2012-08-01T23:59:59.000Z

377

J10: Characterization of Residual Coarse Defects in Translucent ...  

Science Conference Proceedings (OSTI)

A18: Effect of Local Alendronate Delivery on In Vivo Osteogenesis From PCL ... A7: On-the-fly System Design for High Precision/Ultra Fast/Wide Area Fabrication .... C19: Dissolution Behavior of Cu Under Bump Metallization in Ball Grid Array ... High Volume and Fast Turnaround Automated Inline TEM Sample Preparation.

378

Point-defect optical transitions and thermal ionization energies from quantum Monte Carlo methods: Application to the F-center defect in MgO  

E-Print Network (OSTI)

We present an approach to calculation of point-defect optical and thermal ionization energies based on the highly accurate quantum Monte Carlo methods. The use of an inherently many-body theory that directly treats electron ...

Ertekin, Elif

379

Mechanics of graded wrinkling  

E-Print Network (OSTI)

The properties of a surface depend on the inherent material and the surface topography. Nature uses surface texture as a means to impact different surface behavior such as cleanliness, adhesion control, drag reduction, ...

Raayai Ardakani, Shabnam

2013-01-01T23:59:59.000Z

380

Acceleration of dormant storage effects to address the reliability of silicon surface micromachined Micro-Electro-Mechanical Systems (MEMS).  

SciTech Connect

Qualification of microsystems for weapon applications is critically dependent on our ability to build confidence in their performance, by predicting the evolution of their behavior over time in the stockpile. The objective of this work was to accelerate aging mechanisms operative in surface micromachined silicon microelectromechanical systems (MEMS) with contacting surfaces that are stored for many years prior to use, to determine the effects of aging on reliability, and relate those effects to changes in the behavior of interfaces. Hence the main focus was on 'dormant' storage effects on the reliability of devices having mechanical contacts, the first time they must move. A large number ({approx}1000) of modules containing prototype devices and diagnostic structures were packaged using the best available processes for simple electromechanical devices. The packaging processes evolved during the project to better protect surfaces from exposure to contaminants and water vapor. Packages were subjected to accelerated aging and stress tests to explore dormancy and operational environment effects on reliability and performance. Functional tests and quantitative measurements of adhesion and friction demonstrated that the main failure mechanism during dormant storage is change in adhesion and friction, precipitated by loss of the fluorinated monolayer applied after fabrication. The data indicate that damage to the monolayer can occur at water vapor concentrations as low as 500 ppm inside the package. The most common type of failure was attributed to surfaces that were in direct contact during aging. The application of quantitative methods for monolayer lubricant analysis showed that even though the coverage of vapor-deposited monolayers is generally very uniform, even on hidden surfaces, locations of intimate contact can be significantly depleted in initial concentration of lubricating molecules. These areas represent defects in the film prone to adsorption of water or contaminants that can cause movable structures to adhere. These analysis methods also indicated significant variability in the coverage of lubricating molecules from one coating process to another, even for identical processing conditions. The variability was due to residual molecules left in the deposition chamber after incomplete cleaning. The coating process was modified to result in improved uniformity and total coverage. Still, a direct correlation was found between the resulting static friction behavior of MEMS interfaces, and the absolute monolayer coverage. While experimental results indicated that many devices would fail to start after aging, the modeling approach used here predicted that all the devices should start. Adhesion modeling based upon values of adhesion energy from cantilever beams is therefore inadequate. Material deposition that bridged gaps was observed in some devices, and potentially inhibits start-up more than the adhesion model indicates. Advances were made in our ability to model MEMS devices, but additional combined experimental-modeling studies will be needed to advance the work to a point of providing predictive capability. The methodology developed here should prove useful in future assessments of device aging, however. Namely, it consisted of measuring interface properties, determining how they change with time, developing a model of device behavior incorporating interface behavior, and then using the age-aware interface behavior model to predict device function.

Cox, James V.; Candelaria, Sam A.; Dugger, Michael Thomas; Duesterhaus, Michelle Ann; Tanner, Danelle Mary; Timpe, Shannon J.; Ohlhausen, James Anthony; Skousen, Troy J.; Jenkins, Mark W.; Jokiel, Bernhard, Jr.; Walraven, Jeremy Allen; Parson, Ted Blair

2006-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

QUICK QUANTUM MECHANICS ---Introduction ---  

E-Print Network (OSTI)

QUICK QUANTUM MECHANICS --- Introduction --- The following notes are intended to be a supplement to your study of Liboff's ``Introductory Quantum Mechanics.'' They are not an alternative! My purpose here of Classical Mechanics After Newton found his equations of motion, physicists knew they would have to wait

Jackson, Andrew D.

382

HYDRAULIC SERVO CONTROL MECHANISM  

DOE Patents (OSTI)

A hydraulic servo control mechanism of compact construction and low fluid requirements is described. The mechanism consists of a main hydraulic piston, comprising the drive output, which is connected mechanically for feedback purposes to a servo control piston. A control sleeve having control slots for the system encloses the servo piston, which acts to cover or uncover the slots as a means of controlling the operation of the system. This operation permits only a small amount of fluid to regulate the operation of the mechanism, which, as a result, is compact and relatively light. This mechanism is particuiarly adaptable to the drive and control of control rods in nuclear reactors. (auth)

Hussey, R.B.; Gottsche, M.J. Jr.

1963-09-17T23:59:59.000Z

383

Principal component analysis based on wavelet characteristics applied to automated surface defect inspection  

Science Conference Proceedings (OSTI)

Automated visual inspection, a crucial manufacturing step, has been replacing the more time-consuming and less accurate human inspection. This research explores automated visual inspection of surface defects in a light-emitting diode (LED) chip. Commonly ... Keywords: hotelling statistic, machine vision system, principal component analysis, surface defect inspection, wavelet characteristics

Hong-Dar Lin; Chung-Yu Chung; Wan-Ting Lin

2008-04-01T23:59:59.000Z

384

Defect Clusters: Approaches for Overcoming Their Detrimental Impact on Solar Cell Performance  

DOE Green Energy (OSTI)

Our analyses show that defect clusters can lower the efficiency of multicrystalline silicon (mc-Si) solar cells by 2 to 4 absolute percentage points. This large loss can be recovered if impurities precipitated at the defect cluster sites can be gettered. We describe a new technique for gettering precipitated impurities.

Sopori, B.; Tan, T.; Carlson, D.

2005-11-01T23:59:59.000Z

385

Defect prediction from static code features: current results, limitations, new approaches  

Science Conference Proceedings (OSTI)

Building quality software is expensive and software quality assurance (QA) budgets are limited. Data miners can learn defect predictors from static code features which can be used to control QA resources; e.g. to focus on the parts of the code predicted ... Keywords: Defect prediction, Static code features, WHICH

Tim Menzies; Zach Milton; Burak Turhan; Bojan Cukic; Yue Jiang; Ay?e Bener

2010-12-01T23:59:59.000Z

386

Impurity-defect interaction in polycrystalline silicon for photovoltaic applications. The role of hydrogen  

E-Print Network (OSTI)

of the cell ? ii) Will the defects of the polycrystalline material hinder the photovoltaic properties..., leading also to a degradation of the efficiency of the photovoltaic cells ? iii) What would655 Impurity-defect interaction in polycrystalline silicon for photovoltaic applications. The role

Paris-Sud XI, Université de

387

Mechanical Seal Assembly  

DOE Patents (OSTI)

An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

Kotlyar, Oleg M.

1999-06-18T23:59:59.000Z

388

Mechanical seal assembly  

DOE Patents (OSTI)

An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

Kotlyar, Oleg M. (Salt Lake City, UT)

2001-01-01T23:59:59.000Z

389

Defects and Defect Processes  

Science Conference Proceedings (OSTI)

Feb 28, 2011... data, including data from commercial reactor surveillance programs. ... Stanislav Golubov1; Alexander Barashev2; Roger Stoller1; 1ORNL;...

390

Mechanisms of gas bubble retention  

Science Conference Proceedings (OSTI)

Retention and episodic release of flammable gases are critical safety concerns regarding double-shell tanks (DSTs) containing waste slurries. Previous investigations have concluded that gas bubbles are retained by the slurry that has settled at the bottom of the DST. However, the mechanisms responsible for the retention of these bubbles are not well understood. In addition, the presence of retained gas bubbles is expected to affect the physical properties of the sludge, but essentially no literature data are available to assess the effect of these bubbles. The rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles. The objectives of this study are to elucidate the mechanisms contributing to gas bubble retention and release from sludge such as is in Tank 241-SY-101, understand how the bubbles affect the physical properties of the sludge, develop correlations of these physical properties to include in computer models, and collect experimental data on the physical properties of simulated sludges with bubbles. This report presents a theory and experimental observations of bubble retention in simulated sludge and gives correlations and new data on the effect of gas bubbles on sludge yield strength.

Gauglitz, P.A.; Mahoney, L.A.; Mendoza, D.P.; Miller, M.C.

1994-09-01T23:59:59.000Z

391

Characterization of shape memory alloys for safety mechanisms.  

SciTech Connect

Shape memory alloys (SMAs) are metals that exhibit large recoverable strains and exert large forces with tremendous energy densities. The behavior of SMAs is thermomechanically coupled. Their response to temperature is sensitive to their loading condition and their response to loading is sensitive to their thermal condition. This coupled behavior is not to be circumvented, but to be confronted and understood, since it is what manifests SMA's superior clamping performance. To reasonably characterize the coupled behavior of SMA clamping rings used in safety mechanisms, we conduct a series of experiments on SMA samples. The results of the tests will allow increased fidelity in modeling and failure analysis of parts.

McLaughlin, Jarred T.; Buchheit, Thomas Edward; Massad, Jordan Elias

2008-03-01T23:59:59.000Z

392

Characterization of shape memory alloys for safety mechanisms.  

SciTech Connect

Shape memory alloys (SMAs) are metals that exhibit large recoverable strains and exert large forces with tremendous energy densities. The behavior of SMAs is thermomechanically coupled. Their response to temperature is sensitive to their loading condition and their response to loading is sensitive to their thermal condition. This coupled behavior is not to be circumvented, but to be confronted and understood, since it is what manifests SMA's superior clamping performance. To reasonably characterize the coupled behavior of SMA clamping rings used in safety mechanisms, we conduct a series of experiments on SMA samples. The results of the tests will allow increased fidelity in modeling and failure analysis of parts.

McLaughlin, Jarred T.; Buchheit, Thomas Edward; Massad, Jordan Elias

2008-03-01T23:59:59.000Z

393

Mechanics of Electrodes in Lithium-ion Batteries A dissertation presented  

E-Print Network (OSTI)

#12;Mechanics of Electrodes in Lithium-ion Batteries A dissertation presented by Kejie Zhao, Joost J. Vlassak Kejie Zhao Mechanics of Electrodes in Lithium-ion Batteries Abstract This thesis investigates the mechanical behavior of electrodes in Li-ion batteries. Each electrode in a Li-ion battery

394

Noncontact Laser Scanner for Fuel Rod Defect and Wear Measurements  

Science Conference Proceedings (OSTI)

Wear of fuel rod cladding due to mechanical fretting with grid springs and dimples may lead to fuel failures. This is known throughout the nuclear industry as grid-to-rod fretting (GTRF) and is currently the leading fuel failure mechanism in the U.S. pressurized water reactor (PWR) fleet. Utilities and fuel inspection service companies continue to develop advanced technologies to accurately measure fretting wear in order to determine the margin to GTRF-induced fuel failures, while minimizing impacts ...

2013-05-08T23:59:59.000Z

395

Characterization of porosity in support of mechanical property analysis  

SciTech Connect

Previous laboratory investigations of tuff have shown that porosity has a dominant, general effect on mechanical properties. As a result, it is very important for the interpretation of mechanical property data that porosity is measured on each sample tested. Porosity alone, however, does not address all of the issues important to mechanical behavior. Variability in size and distribution of pore space produces significantly different mechanical properties. A nondestructive technique for characterizing the internal structure of the sample prior to testing is being developed and the results are being analyzed. The information obtained from this technique can help in both qualitative and quantitative interpretation of test results.

Price, R.H. [Sandia National Labs., Albuquerque, NM (United States); Martin, R.J. III; Boyd, P.J. [New England Research, Inc., White River Junction, VT (United States)

1992-12-31T23:59:59.000Z

396

A study of defects on EUV mask using blank inspection, patterned mask inspection, and wafer inspection  

SciTech Connect

The availability of defect-free masks remains one of the key challenges for inserting extreme ultraviolet lithography (EUVL) into high volume manufacturing. yet link data is available for understanding native defects on real masks. In this paper, a full-field EUV mask is fabricated to investigate the printability of various defects on the mask. The printability of defects and identification of their source from mask fabrication to handling were studied using wafer inspection. The printable blank defect density excluding particles and patterns is 0.63 cm{sup 2}. Mask inspection is shown to have better sensitivity than wafer inspection. The sensitivity of wafer inspection must be improved using through-focus analysis and a different wafer stack.

Huh, S.; Ren, L.; Chan, D.; Wurm, S.; Goldberg, K. A.; Mochi, I.; Nakajima, T.; Kishimoto, M.; Ahn, B.; Kang, I.; Park, J.-O.; Cho, K.; Han, S.-I.; Laursen, T.

2010-03-12T23:59:59.000Z

397

An Atom-Wide Antennae Created from Difference-Making Defects | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

An Atom-Wide Antennae Created from Difference-Making Defects An Atom-Wide Antennae Created from Difference-Making Defects An Atom-Wide Antennae Created from Difference-Making Defects March 7, 2012 - 3:35pm Addthis Take advantage of microwave microscopy, researchers were able to locate graphene islands on graphene. “Point defects” locally enhanced the graphene’s ability to transform waves of light into electronic signals. | Photo courtesy of Oak Ridge National Laboratory. Take advantage of microwave microscopy, researchers were able to locate graphene islands on graphene. "Point defects" locally enhanced the graphene's ability to transform waves of light into electronic signals. | Photo courtesy of Oak Ridge National Laboratory. Charles Rousseaux Charles Rousseaux Senior Writer, Office of Science

398

Effect of irradiation parameters on defect aggregation during thermal annealing of LiF irradiated with swift ions and electrons  

SciTech Connect

Absorption spectroscopy were performed to study the effects of thermal annealing on the aggregation of color centers in LiF crystals irradiated with different ions between carbon and uranium of megaelectron volt-gigaelectron volt energy. The beam parameters such as energy, energy loss, and fluence have a pronounced influence on the initial defect composition and concentration as well as their evolution upon thermal annealing. A distinct phenomenon was observed, viz., the enhancement of F{sub n} centers for annealing temperatures between 500 and 700 K, followed by Li colloid formation above 700 K. The phenomenon requires specific irradiation conditions whereas the formation of Mg colloids from Mg impurities occurs in all irradiated crystals. The mechanisms of annealing and colloid formation are discussed.

Schwartz, K.; Neumann, R.; Trautmann, C. [GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstr. 1, 64291 Darmstadt (Germany); Volkov, A. E.; Sorokin, M. V. [Russian Research Center 'Kurchatov Institute', Kurchatov Square 1, 123182 Moscow (Russian Federation)

2010-10-01T23:59:59.000Z

399

Vacancy-driven anisotropic defect distribution in the battery-cathode material LiFePO4  

Science Conference Proceedings (OSTI)

Li-ion mobility in LiFePO{sub 4}, a key property for energy applications, is impeded by Fe antisite defects (Fe{sub Li}) that form in select b-axis channels. Here we combine first-principles calculations, statistical mechanics, and scanning transmission electron microscopy to identify the origin of the effect: Li vacancies (V{sub Li}) are confined in one-dimensional b-axis channels, shuttling between neighboring Fe{sub Li}. Segregation in select channels results in shorter Fe{sub Li}-Fe{sub Li} spans, whereby the energy is lowered by the V{sub Li}'s spending more time bound to end-point Fe{sub Li}'s. V{sub Li}-Fe{sub Li}-V{sub Li} complexes also form, accounting for observed electron energy loss spectroscopy features.

Lee, Jaekwang [Vanderbilt University; Zhou, Wu [Vanderbilt University; Idrobo Tapia, Juan C [ORNL; Pennycook, Stephen J [ORNL; Pantelides, Sokrates T. [Vanderbilt University; Biegalski, Michael D [ORNL

2011-01-01T23:59:59.000Z

400

Modeling robot behavior with CCL  

Science Conference Proceedings (OSTI)

This paper presents the use of a Concurrent Communicating Lists (CCL) library in robot behavior modeling. CCL provides several software components, which allow the model to be built, simulated and formally verified. Due to the integration ...

Konrad Ku?akowski; Tomasz Szmuc

2012-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Alternative models of OPEC behavior  

Science Conference Proceedings (OSTI)

Since the 1973 oil price jump there has been considerable interest in the Organization of the Petroleum Exporting Countries (OPEC) and its role in the international oil market. However, most of the literature on this subject is mainly concerned with either a time-control problem in which the optimality and implication of certain market behavior is analyzed or a simulation of the oil market assuming a particular market behavior by OPEC members. Our objective in this preliminary research is to present a unified framework in which we construct models of viable alternative market behaviors for OPEC members assuming profit-maximization behavior. Each model will be specified as a system of nonlinear simultaneous equations, and for a particular functional forms specification, we present the estimates of the first two models considered.

Al-Sultan, A.M.

1993-12-31T23:59:59.000Z

402

The Defect Induced Mix Experiment (DIME) for NIF  

SciTech Connect

LANL will perform two Defect Induced Mix Experiment (DIME) implosion campaigns on NIF in July and September, 2012. This presentation describes the goals for these shots and the experimental configuration and diagnostic set up to collect the appropriate data. The first two-shot campaign will focus on executing polar direct drive (PDD) implosions of plastic CH capsules filled with deuterium gas. Gas filling will be performed through a fill tube at target chamber center. A vanadium backligher foil will provide x-rays to radiograph the last half of the implosion to compare the implosion trajectory with modeling predictions. An equatorial groove in one of the capsules will be present to determine its effect on implosion dynamics. The second DIME campaign will commission and use a spectral imager (MMI) to examine the evolution of thin capsule layers doped with either Ge or Ga at 1.85%. Spectral line emission from these layers will quantify the mix width at the inner shell radius and near an equatorial groove feature.

Schmitt, Mark J [Los Alamos National Laboratory; Bradley, Paul A [Los Alamos National Laboratory; Cobble, James A [Los Alamos National Laboratory; Hakel, Peter [Los Alamos National Laboratory; Hsu, Scott C [Los Alamos National Laboratory; Krasheninnikova, Natalia S [Los Alamos National Laboratory; Kyrala, George A [Los Alamos National Laboratory; Murphy, Thomas J [Los Alamos National Laboratory; Obrey, Kimberly A [Los Alamos National Laboratory; Shah, Rahul C [Los Alamos National Laboratory; Tregillis, Ian L [Los Alamos National Laboratory

2012-06-18T23:59:59.000Z

403

Control of Suspect/Counterfeit and Defective Items  

Science Conference Proceedings (OSTI)

This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventing the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.

Sheriff, Marnelle L.

2013-09-03T23:59:59.000Z

404

Mechanics of Funding matrix  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

FUNDING MECHANISMS FUNDING MECHANISMS Funding Mechanism Advantages Disadvantages Comments 1. From Doe to regional organizations * * Facilitates a broad, regional approach to planning and implementation that enhances consistency and uniformity * * Especially beneficial for new programs where early planning is needed * * Simplifies communication for DOE to have only one point of contact for information and discussion * * Cooperative agreement mechanism has proven relatively simple to administer * * Approach would require modification for Tribes * * Would also require that funding be provided to individual States to enable them to participate in the process, since planning authority and responsibility rests with the individual State * * Differs from OCRWM approach to 180(c) funding * * Introduces another layer of

405

Structures and Mechanical Properties  

Science Conference Proceedings (OSTI)

Mar 7, 2013... Refractory High-entropy Alloy: Chien-Chang Juan1; Jien-Wei Yeh1; ... The main wear mechanism was adhesive wear in deionized water,...

406

A nanocrystal strain gauge for luminescence detection of mechanical forces  

Science Conference Proceedings (OSTI)

Local microscale stresses play a crucial role in inhomogeneous mechanical processes from cell motility to material failure. However, it remains difficult to spatially resolve stress at these small length scales. While contact-probe and non-contact based techniques have been used to quantify local mechanical behavior in specific systems with high stiffness or stress and spatial resolution, these methods cannot be used to study a majority of micromechanical systems due to spectroscopic and geometrical constraints. We present here the design and implementation of a luminescent nanocrystal strain gauge, the CdSe/CdS core/shell tetrapod. The tetrapod can be incorporated into many materials, yielding a local stress measurement through optical fluorescence spectroscopy of the electronically confined CdSe core states. The stress response of the tetrapod is calibrated and utilized to study mechanical behavior in single polymer fibers. We expect that tetrapods can be used to investigate local stresses in many other mechanical systems.

Choi, Charina; Koski, Kristie; Olson, Andrew; Alivisatos, Paul

2010-07-26T23:59:59.000Z

407

Optical method and apparatus for detection of surface and near-subsurface defects in dense ceramics  

DOE Patents (OSTI)

A laser is used in a non-destructive manner to detect surface and near-subsurface defects in dense ceramics and particularly in ceramic bodies with complex shapes such as ceramic bearings, turbine blades, races, and the like. The laser`s wavelength is selected based upon the composition of the ceramic sample and the laser can be directed on the sample while the sample is static or in dynamic rotate or translate motion. Light is scattered off surface and subsurface defects using a preselected polarization. The change in polarization angle is used to select the depth and characteristics of surface/subsurface defects. The scattered light is detected by an optical train consisting of a charge coupled device (CCD), or vidicon, television camera which, in turn, is coupled to a video monitor and a computer for digitizing the image. An analyzing polarizer in the optical train allows scattered light at a given polarization angle to be observed for enhancing sensitivity to either surface or near-subsurface defects. Application of digital image processing allows subtraction of digitized images in near real-time providing enhanced sensitivity to subsurface defects. Storing known ``feature masks`` of identified defects in the computer and comparing the detected scatter pattern (Fourier images) with the stored feature masks allows for automatic classification of detected defects. 29 figs.

Ellingson, W.A.; Brada, M.P.

1995-06-20T23:59:59.000Z

408

Optical method and apparatus for detection of surface and near-subsurface defects in dense ceramics  

DOE Patents (OSTI)

A laser is used in a non-destructive manner to detect surface and near-subsurface defects in dense ceramics and particularly in ceramic bodies with complex shapes such as ceramic bearings, turbine blades, races, and the like. The laser's wavelength is selected based upon the composition of the ceramic sample and the laser can be directed on the sample while the sample is static or in dynamic rotate or translate motion. Light is scattered off surface and subsurface defects using a preselected polarization. The change in polarization angle is used to select the depth and characteristics of surface/subsurface defects. The scattered light is detected by an optical train consisting of a charge coupled device (CCD), or vidicon, television camera which, in turn, is coupled to a video monitor and a computer for digitizing the image. An analyzing polarizer in the optical train allows scattered light at a given polarization angle to be observed for enhancing sensitivity to either surface or near-subsurface defects. Application of digital image processing allows subtraction of digitized images in near real-time providing enhanced sensitivity to subsurface defects. Storing known "feature masks" of identified defects in the computer and comparing the detected scatter pattern (Fourier images) with the stored feature masks allows for automatic classification of detected defects.

Ellingson, William A. (Naperville, IL); Brada, Mark P. (Goleta, CA)

1995-01-01T23:59:59.000Z

409

PROPERTIES OF DEFECTS AND IMPLANTS IN Mg+ IMPLANTED SILICON CARBIDE  

SciTech Connect

As a candidate material for fusion reactor designs, silicon carbide (SiC) under high-energy neutron irradiation undergoes atomic displacement damage and transmutation reactions that create magnesium as one of the major metallic products. The presence of Mg and lattice disorder in SiC is expected to affect structural stability and degrade thermo-mechanical properties that could limit SiC lifetime for service. We have initiated a combined experimental and computational study that uses Mg+ ion implantation and multiscale modeling to investigate the structural and chemical effects in Mg implanted SiC and explore possible property degradation mechanisms.

Jiang, Weilin; Zhu, Zihua; Varga, Tamas; Bowden, Mark E.; Manandhar, Sandeep; Roosendaal, Timothy J.; Hu, Shenyang Y.; Henager, Charles H.; Kurtz, Richard J.; Wang, Yongqiang

2013-09-25T23:59:59.000Z

410

Normalization of the scattered light from an isolated defect illuminated by a Gaussian beam  

SciTech Connect

The intensity distribution of the beam from a laser operated in the zero order configuration for the transverse electromagnetic field (TEM/sub 00/ mode) is Gaussian in a plane perpendicular to the axis of the beam. In some applications it is desirable to have a uniform intensity over a certain region in space. For example, when a Gaussian beam is incident on a smooth surface containing small isolated defects, the light scattered by a defect will depend on the position of the defect relative to the center of the beam. In the past, several techniques have been devised to convert a Gaussian intensity profile into a uniform intensity over a specified region in space. In the present work a different approach is taken. A method of normalization is described which makes direct use of the Gaussian intensity distribution of the TEM/sub 00/ mode. By this method the amount of light scattered by a defect can be normalized to the value which would be observed if the defect were located at the center of the beam, for a defect small in size compared with the 1/e/sup 2/ diameter of the Gaussian profile. The normalization requires that three measurements be made of the scattering by the defect for an arbitrary location of the defect relative to the center of the Gaussian beam, and that the 1/e/sup 2/ radius of the Gaussian beam and the interval between adjacent illuminated spots on the surface are known. Experimental data verifying the theory were obtained from isolated defects on a superfinished spherical surface.

Klingsporn, P.E.

1980-07-01T23:59:59.000Z

411

Mecanica Clasica (Classical Mechanics)  

E-Print Network (OSTI)

First Internet undergraduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031

Rosu, H C

1999-01-01T23:59:59.000Z

412

Quantum Mechanics Measurements, Mutually  

E-Print Network (OSTI)

Quantum Mechanics Measurements, Mutually Unbiased Bases and Finite Geometry Or why six is the first) #12;Quantum Mechanics for Dummies Finite dimensional quantum states are represented by trace one,1 -icS1,1[ ] #12;Quantum systems evolve and are measured. The evolution of a quantum system using

Gruner, Daniel S.

413

Mechanical code comparator  

DOE Patents (OSTI)

A new class of mechanical code comparators is described which have broad potential for application in safety, surety, and security applications. These devices can be implemented as micro-scale electromechanical systems that isolate a secure or otherwise controlled device until an access code is entered. This access code is converted into a series of mechanical inputs to the mechanical code comparator, which compares the access code to a pre-input combination, entered previously into the mechanical code comparator by an operator at the system security control point. These devices provide extremely high levels of robust security. Being totally mechanical in operation, an access control system properly based on such devices cannot be circumvented by software attack alone.

Peter, Frank J. (Albuquerque, NM); Dalton, Larry J. (Bernalillo, NM); Plummer, David W. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

414

Analysis, Simulation and Prediction of Cosmetic Defects on Automotive External Panel  

Science Conference Proceedings (OSTI)

The first feeling of quality for a vehicle is linked to its perfect appearance. This has a major impact on the reputation of a car manufacturer. Cosmetic defects are thus more and more taken into account in the process design. Qualifying a part as good or bad from the cosmetic point of view is mainly subjective: the part aspect is considered acceptable if no defect is visible on the vehicle by the final customer. Cosmetic defects that appear during sheet metal forming are checked by visual inspection in light inspection rooms

A. Le Port; S. Thuillier; C. Borot; J. Charbonneaux; Aethra Automotive Systems

2011-01-01T23:59:59.000Z

415

Correlation between nuclear response and defects in CZT  

Science Conference Proceedings (OSTI)

Vertical high pressure Bridgman (VHPB) was considered until now to be the most successful crystal growth method to produce Cd{sub 1{minus}x}Zn{sub x}Te (CZT), (0.04 < x < 0.24), for X- and gamma-ray detector crystals. Recently Horizontal Bridgman (HB) Cd{sub 1{minus}x}Zn{sub x}Te crystals produced by IMARAD Co. have also been successfully fabricated into nuclear spectroscopic radiation detectors. In view of the database of many years' study of the electrical properties of VHPB CZT grown and obtained from various sources, the authors also studied the HB CZT crystals in order to compare the defects present in both different kinds of crystals grown by different methods. The VHB-grown samples were examined using thermoelectric emission spectroscopy (TEES), X- and gamma ray spectroscopy and laser induced transient charge technique (TCT). The surface and the bulk crystalline homogeneity were mapped using triaxial double crystal x-ray diffraction (TADXRD) and infrared transmission spectroscopy (IR). They have found a correlation between crystallinity, IR transmission microstructure and trapping times. Spectrometer grade VHPB CZT crystals exhibit trapping times of 20 {micro}s for electrons and 7 {micro}s for holes, however, regions, which were opaque to IR transmission, had trapping times shorter by one order of magnitude. The trapping times of HB CZT for electrons, were 10--15 {micro}s. A similar trend has been observed on VHPB CZT crystals with poor crystallinity. The HB CZT crystals that they measured in this study had a crystallinity that was inferior to that of the best spectroscopic grade VHPB crystals.

H. Hermon; M. Schieber; R. B. James; E. Lee; E. Cross; M. Goorsky; T. Lam; T. E. Schlesinger; M. Greaves

1999-07-19T23:59:59.000Z

416

Structural Mechanics & Solid Mechanics A finite element toolbox to MATLAB  

E-Print Network (OSTI)

Structural Mechanics & Solid Mechanics Department of Mechanics and Materials CALFEM A finite.3 Copyright © 1999 by Structural Mechanics, LTH, Sweden. Printed by JABE Offset, Lund, Sweden. ISRN LUTVDG/TVSM--99/9001--SE (1-265) ISSN 0281-6679 Department of Mechanics and Materials Structural Mechanics #12;The

Ehrhardt, Matthias

417

Corrosion Behavior of Aluminum Matrix Composite (AMCS)  

Science Conference Proceedings (OSTI)

A Study on the Stress Test of Truck Frames for Freight Trains A Study on the ... Defect Energetics and Fission Product Transport in ZrC Deformation Field and...

418

MECHANICAL PROPERTY CHARACTERIZATION OF SOL-GEL DERIVED NANOMATERIALS  

E-Print Network (OSTI)

mechanical behavior of polysilicate aerogels, prepared using the sol-gel process. Two series of materials were prepared, derivatized with silylating agents, processed into coating solutions, and characterized properties of aerogel thin films were characterized. vi #12;Table of Contents Abstract

Brinker, C. Jeffrey

419

Rotary mechanical latch  

Science Conference Proceedings (OSTI)

A rotary mechanical latch for positive latching and unlatching of a rotary device with a latchable rotating assembly having a latching gear that can be driven to latched and unlatched states by a drive mechanism such as an electric motor. A cam arm affixed to the latching gear interfaces with leading and trailing latch cams affixed to a flange within the drive mechanism. The interaction of the cam arm with leading and trailing latch cams prevents rotation of the rotating assembly by external forces such as those due to vibration or tampering.

Spletzer, Barry L.; Martinez, Michael A.; Marron, Lisa C.

2012-11-13T23:59:59.000Z

420

Quantum Mechanics Without Observers  

E-Print Network (OSTI)

The measurement problem and the role of observers have plagued quantum mechanics since its conception. Attempts to resolve these have introduced anthropomorphic or non-realist notions into physics. A shift of perspective based upon process theory and utilizing methods from combinatorial games, interpolation theory and complex systems theory results in a novel realist version of quantum mechanics incorporating quasi-local, nondeterministic hidden variables that are compatible with the no-hidden variable theorems and relativistic invariance, and reproduce the standard results of quantum mechanics to a high degree of accuracy without invoking observers.

W. H. Sulis

2013-02-18T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Electronic door locking mechanism  

DOE Patents (OSTI)

The invention is a motorized linkage for engaging a thumb piece in a door mechanism. The device has an exterior lock assembly with a small battery cell and combination lock. Proper entry by a user of a security code allows the battery to operate a small motor within the exterior lock assembly. The small motor manipulates a cam-plunger which moves an actuator pin into a thumb piece. The user applies a force on to the thumb piece. This force is transmitted by the thumb piece to a latch engagement mechanism by the actuator pin. The latch engagement mechanism operates the door latch. 6 figs.

Williams, G.L.; Kirby, P.G.

1997-10-21T23:59:59.000Z

422

Electronic door locking mechanism  

SciTech Connect

The invention is a motorized linkage for engaging a thumb piece in a door mechanism. The device has an exterior lock assembly with a small battery cell and combination lock. Proper entry by a user of a security code allows the battery to operate a small motor within the exterior lock assembly. The small motor manipulates a cam-plunger which moves an actuator pin into a thumb piece. The user applies a force on to the thumb piece. This force is transmitted by the thumb piece to a latch engagement mechanism by the actuator pin. The latch engagement mechanism operates the door latch.

Williams, Gary Lin (428 E. Third Ave., Kennewick, WA 99336); Kirby, Patrick Gerald (1010 W. Fifteenth Pl., Kennewick, WA 99337)

1997-01-01T23:59:59.000Z

423

Is quantum mechanics exact?  

SciTech Connect

We formulate physically motivated axioms for a physical theory which for systems with a finite number of degrees of freedom uniquely lead to quantum mechanics as the only nontrivial consistent theory. Complex numbers and the existence of the Planck constant common to all systems arise naturally in this approach. The axioms are divided into two groups covering kinematics and basic measurement theory, respectively. We show that even if the second group of axioms is dropped, there are no deformations of quantum mechanics which preserve the kinematic axioms. Thus, any theory going beyond quantum mechanics must represent a radical departure from the usual a priori assumptions about the laws of nature.

Kapustin, Anton [California Institute of Technology, Pasadena, California 91125 (United States)] [California Institute of Technology, Pasadena, California 91125 (United States)

2013-06-15T23:59:59.000Z

424

Experimental Verification of Thermo-Mechanical Models for XLPE Cable in Pipes and Ducts  

Science Conference Proceedings (OSTI)

In 2002 EPRI began investigations of the thermo-mechanical (T-M) behavior of transmission-class cable systems with extruded insulation in duct-manhole and pipe systems and began work on a design guide. The project consisted primarily of two efforts: experimental measurement of cable parameters and development of a mathematical simulation of the thermal and mechanical behavior of transmission-class cable with extruded cross-linked polyethylene (XLPE) insulation when installed in ducts and pipes. ...

2012-12-20T23:59:59.000Z

425

Dynamic Behavior of Reactive Materials  

Science Conference Proceedings (OSTI)

Feb 28, 2011 ... Investigation of Al-Metal Reactions Induced by High-Rate Mechanical Loading: Eric Herbold1; Jennifer Jordan2; Naresh Thadhani1; 1Georgia...

426

Paperwork: Buckypapers Clarify Electrical, Optical Behavior of ...  

Science Conference Proceedings (OSTI)

Paperwork: Buckypapers Clarify Electrical, Optical Behavior of Nanotubes. For Immediate Release: October 14, 2008. ...

2012-10-18T23:59:59.000Z

427

Joint Summer School on "The Evolution and Impact of Microstructural Defects  

Office of Science (SC) Website

Joint Summer School on "The Evolution and Impact Joint Summer School on "The Evolution and Impact of Microstructural Defects on In-Reactor Material Response" Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News EFRC Events DOE Announcements Publications Contact BES Home 11.08.10 Joint Summer School on "The Evolution and Impact of Microstructural Defects on In-Reactor Material Response" Print Text Size: A A A Subscribe FeedbackShare Page June 6 - 10, 2011 :: The International Summer School, "The Evolution and Impact of Microstructural Defects on In-Reactor Material Response", at Idaho National Laboratories will be sponsored by the Center for Materials Science of Nuclear Fuel (Idaho National Laboratory), the Center for Defect

428

Structure and Effects of Extended Defects in Polycrystalline Si Thin Films  

DOE Green Energy (OSTI)

The structure and effects of extended defects in rapid deposited polycrystalline Si thin films were studied using a combination of high-resolution transmission electron microscopy and first-principles total energy calculations.

Yan, Y.; Al-Jassim, M. M.; Wang, T. H.; Ciszek, T. F.

2000-01-01T23:59:59.000Z

429

Origin of radiation tolerance in 3C-SiC with nanolayered planar defects  

SciTech Connect

We have recently found that the radiation tolerance of SiC is highly enhanced by introducing nanolayers of stacking faults and twins [Y. Zhang et al., Phys. Chem. Chem. Phys. 14, 13429 (2012)]. To reveal the origin of this radiation resistance, we used in situ transmission electron microscopy to examine structural changes induced by electron beam irradiation in 3C-SiC containing nanolayers of (111) planar defects. We found that preferential amorphization, when it does occur, takes place at grain boundaries and at 111 and 111 planar defects. Radiationinduced point defects, such as interstitials and vacancies, migrate two-dimensionally between the (111) planar defects, which probably enhances the damage recovery.

Ishimaru, Dr. Manabu [Osaka University; Zhang, Yanwen [ORNL; Shannon, Prof. Steven [North Carolina State University; Weber, William J [ORNL

2013-01-01T23:59:59.000Z

430

Electrostatic in Reissner-Nordstrom space-time with a conical defect  

E-Print Network (OSTI)

We calculate the electrostatic potential generated by a point charge in the space-time of Reissner-Nordstrom with a conical defect. An expression for the self-energy is also presented.

J. Spinelly; V. B. Bezerra

2000-12-19T23:59:59.000Z

431

Origin of radiation tolerance in 3C-SiC with nanolayered planar defects  

SciTech Connect

We have recently found that the radiation tolerance of SiC is highly enhanced by introducing nanolayers of stacking faults and twins [Y. Zhang et al., Phys. Chem. Chem. Phys. 14, 13429 (2012)]. To reveal the origin of this radiation resistance, we used in situ transmission electron microscopy to examine structural changes induced by electron beam irradiation in 3C-SiC containing nanolayers of (111) planar defects. We found that preferential amorphization, when it does occur, takes place at grain boundaries and at (111) and (111) planar defects. Radiation-induced point defects, such as interstitials and vacancies, migrate two-dimensionally between the (111) planar defects, which probably enhances the damage recovery.

Ishimaru, Manabu [Institute of Scientific and Industrial Research, Osaka University, Osaka 567-0047 (Japan); Zhang Yanwen; Weber, William J. [Materials Science and Technology Division, Oak Ridge National Laboratory, Tennessee 37831-6138 (United States); Department of Materials Science and Engineering, University of Tennessee, Tennessee 37996 (United States); Shannon, Steven [Department of Nuclear Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

2013-07-15T23:59:59.000Z

432

Electrical properties and defect structures of praseodymium-cerium oxide solid solutions  

E-Print Network (OSTI)

A defect chemistry model consistent with observed trends in the pO2 and temperature dependence of electrical conductivity in praseodymium cerium oxide (PCO) was developed. Four point DC conductivity measurements were made ...

Stefanik, Todd Stanley, 1973-

2004-01-01T23:59:59.000Z

433

Proceedings of the TMS symposium on radiation facilities and defect studies  

Science Conference Proceedings (OSTI)

Intent of the symposium is to highlight the various means of producing and characterizing irradition-induced defects in materials of interest in nuclear applications. Viewgraphs are presented for 18 papers. Separate abstracts were prepared for the data base.

Snead, C.L. Jr. (ed.)

1992-01-01T23:59:59.000Z

434

Proceedings of the TMS symposium on radiation facilities and defect studies  

SciTech Connect

Intent of the symposium is to highlight the various means of producing and characterizing irradition-induced defects in materials of interest in nuclear applications. Viewgraphs are presented for 18 papers. Separate abstracts were prepared for the data base.

Snead, C.L. Jr. [ed.

1992-11-01T23:59:59.000Z

435

Impurity-Point Defect Interaction in Fe-Cr Alloys: Size Effects versus ...  

Science Conference Proceedings (OSTI)

May 1, 2007 ... Impurity-Point Defect Interaction in Fe-Cr Alloys: Size Effects versus Magnetic Behaviour by D. Nguyen-Manh, M.Y. Lavrentiev and S.L....

436

Impact of defect type on hydrogen passivation effectiveness in multicrystalline silicon solar cells  

E-Print Network (OSTI)

In this work we examine the effectiveness of hydrogen passivation at grain boundaries as a function of defect type and microstructure in multicrystalline silicon. We analyze a specially prepared solar cell with alternating ...

Bertoni, Mariana I.

437

Hydrogen effects on the point defect spectrum in Fe-C alloys  

E-Print Network (OSTI)

As part of a multi-scale approach for modeling hydrogen embrittlement in hardened steels we have investigated, employing density functional theory methods, the stability and concentrations of the point defect clusters ...

Monasterio Velsquez, Paul Rene

2008-01-01T23:59:59.000Z

438

Defect structure of indium tin oxide and its relationship to conductivity  

DOE Green Energy (OSTI)

Doping In{sub 2}O{sub 3} with tin results in an improved transparent conducting oxide (TCO). Although indium tin oxide (ITO) is the most frequently used commercial TCO, its defect structure is still uncertain. Previously, its defect chemistry has been inferred based on the conductivity of the material. To directly study the defect structure of ITO, the authors prepared powders under different processing environments and performed neutron powder diffraction. Structural information was obtained by performing Rietveld analysis. The results include positions of the atoms, their thermal displacements, the fractional occupancy of the defect oxygen site, and the fractional occupancies of Sn on each of the two nonequivalent cation sites, showing a strong preference for the b site. These structural results are correlated with the measured electrical properties of the same samples.

Gonzalez, G. B.; Cohen, J. B.; Hwang, J.-H.; Mason, T. O.; Hodges, J. P.; Jorgensen, J. D.

2000-05-09T23:59:59.000Z

439

Defect-Band Emission Photoluminescence Imaging on Multi-Crystalline Si Solar Cells: Preprint  

DOE Green Energy (OSTI)

Defect-band photoluminescence (PL) imaging with an InGaAs camera was applied to multicrystalline silicon (mc-Si) wafers, which were taken from different heights of different Si bricks. Neighboring wafers were picked at six different processing steps, from as-cut to post-metallization. By using different cut-off filters, we were able to separate the band-to-band emission images from the defect-band emission images. On the defect-band emission images, the bright regions that originate from the grain boundaries and defect clusters were extracted from the PL images. The area fraction percentage of these regions at various processing stages shows a correlation with the final cell electrical parameters.

Yan, F.; Johnston, S.; Zaunbrecher, K.; Al-Jassim, M.; Sidelkheir, O.; Blosse, A.

2011-07-01T23:59:59.000Z

440

Unified high-level synthesis and module placement for defect-tolerant microfluidic biochips  

Science Conference Proceedings (OSTI)

Microfluidic biochips promise to revolutionize biosensing and clinical diagnostics. As more bioassays are executed concurrently on a biochip, system integration and design complexity are expected to increase dramatically. This problem is also identified ... Keywords: biochip, defect tolerance, microfluidics, placement, synthesis

Fei Su; Krishnendu Chakrabarty

2005-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Correlations Between Crystal Defects and Performance of CdZnTe Detectors  

Science Conference Proceedings (OSTI)

Poor crystallinity remains a major problem affecting the availability and cost of CdZnTe (CZT) detectors. Point defects are responsible for small gradual charge loss and correlated with the electron clouds' drift times, which allows electronic correction of the output signals to achieve high spectral-resolution even with large-volume CZT detectors. In contrast, extended defects causes significant charge losses, which typically are uncorrelated, and, thus, result in much greater fluctuations of the output signals that cannot be corrected. Although extended defects do not affect all the interaction events, their fraction rapidly increases with the crystal's thickness and volume. In this paper, we summarize our recent results from testing CZT material and detectors that emphasize the particular roles of two types of extended defects, and their contributions to the device's overall performance.

A Bolotnikov; S Babalola; G Camarda; Y Cui; R Gul; S Egarievwe; P Fochuk; M Fuerstnau; J Horace; et al.

2011-12-31T23:59:59.000Z

442

REFLECTED LIGHT INTENSITY DISTRIBUTIONS FROM DEFECTS ON HIGHLY REFLECTIVE SPHERES PDO 6984778, Topical Report  

SciTech Connect

A light reflection technique suitable for development into an automated surface quality certification system was investigated to determine if reflected light intensity distributions could be corre]ated with surface defect depths. Reflected laser light intensity distributions from pit and scratch defects on highly reflective spheres were studied with a commercial multi-element photodetector. It was found that the intensity distributions --Goll'lf be correlated with depths of pits and scratches in a size range of concern on highly reflective' spheres.

Klingsport, P. E.

1977-02-01T23:59:59.000Z

443

Defects and instabilities in Hf-dielectric/SiON stacks (Invited Paper)  

Science Conference Proceedings (OSTI)

In this work, a review on the recent progress in understanding defects and instabilities in Hf-dielectric/SiON stacks will be given for both nMOSFETs and pMOSFETs. The key issues addressed for nMOSFETs include the capture cross section of electron traps, ... Keywords: Defects, Hf-silicates, HfO2, High-k dielectrics, Instability, NBTI, PBTI, Positive charges, Traps

J. F. Zhang

2009-07-01T23:59:59.000Z

444

A Transformer Coupling Method for Imaging Defects in Concentrically Arranged Steel Tubes  

Science Conference Proceedings (OSTI)

This paper describes the development of a system that uses a transformer coupling method for imaging defects in the outer tube of a concentric steel tube pair. Transformer coupling is employed where a receiver is mounted opposite to the transmitter. Magnetic field coupling is used, in which the field propagates through the inner steel tube towards the outer steel tube. Defects in the outer section distort the field and the change is detected by the receiver.

Miller, G.; Hussin, H.; Fernandes, B.; Zaid, M.; Gaydecki, P.; El-Madaani, F. [School of Electrical and Electronic Engineering, University of Manchester, PO Box 88, Manchester M60 1QD (United Kingdom)

2006-03-06T23:59:59.000Z

445

Counter Current Multiplier Mechanism  

NLE Websites -- All DOE Office Websites (Extended Search)

Counter Current Multiplier Mechanism Counter Current Multiplier Mechanism Name: Stephen Location: N/A Country: N/A Date: N/A Question: Can you please explain to me the counter-current multiplier mechanism. I understand that cholride and sodium ions are filtered out of the ascending loop of Henle into the interstial fluid, however, I'm not sure exactly what happens from there and how this effects osmotic pressure gradients in the nephron. Any help would be greatly appriciated. Replies: This mechanism is very complex when it comes to writing a response. You have to have a strong background in osmotic pressure understanding and the anatomy of the kidney. It involves the cortex, outer and inner medula in relationship to the vasa recta, interstitial fluids at two points, the loop of Henle and the collecting duct. The size of the tubes and the position in relations to the cortex and medulla is an essential part. I can suggest some references.

446

Mechanical Testing of Plastics  

Science Conference Proceedings (OSTI)

Table 7   ASTM and ISO mechanical test standards for plastics...by pendulum method D 1938 6383-1 Tear propagation resistance of plastic film and thin

447

Conservative-Bayesian Mechanisms  

E-Print Network (OSTI)

We put forward a new class of mechanisms. In this extended abstract, we exemplify our approach only for single-good auctions in what we call a conservative-Bayesian setting. (Essentially, no common-knowledge about the ...

Azar, Pablo

2010-09-08T23:59:59.000Z

448

3.40J / 22.71J Physical Metallurgy, Spring 2004  

E-Print Network (OSTI)

This course examines how the presence of 1-, 2- and 3D defects and second phases control the mechanical, electromagnetic and chemical behavior of metals and alloys. It considers point, line and interfacial defects in the ...

Russell, Kenneth

449

Annihilation dynamics of stringlike topological defects in a nematic lyotropic liquid crystal  

E-Print Network (OSTI)

Topological defects can appear whenever there is some type of ordering. Its ubiquity in nature has been the subject of several studies, from early Universe to condensed matter. In this work, we investigated the annihilation dynamics of defects and antidefects in a lyotropic nematic liquid crystal (ternary mixture of potassium laurate, decanol and deionized-destilated water) using the polarized optical light microscopy technique. We analyzed Schlieren textures with topological defects produced due to a symmetry breaking in the transition of the isotropic to nematic calamitic phase after a temperature quench. As result, we obtained for the distance D between two annihilating defects (defect-antidefect pair), as a function of time t remaining for the annihilation, the scaling law D ~ t^{\\alpha}, with \\alpha = 0.390 and standard deviation \\sigma = 0.085. Our findings go in the direction to extend experimental results related to dynamics of defects in liquid crystals since only thermotropic and polymerics ones had been investigated. In addition, our results are in good quantitative agreement with previous investigations on the subject.

R. R. Guimares; R. S. Mendes; P. R. G. Fernandes; H. Mukai

2013-04-19T23:59:59.000Z

450

Defect Levels of Indium-doped CdMnTe Crystals  

Science Conference Proceedings (OSTI)

Using photoluminescence (PL) and current deep-level transient spectroscopy (I-DLTS), we investigated the electronic defects of indium-doped detector-grade CdMnTe:In (CMT:In) crystals grown by the vertical Bridgman method. We similarly analyzed CdZnTe:In (CZT:In) and undoped CdMnTe (CMT) crystals grown under the amount of same level of excess Te and/or indium doping level to detail the fundamental properties of the electronic defect structure more readily. Extended defects, existing in all the samples, were revealed by synchrotron white beam x-ray diffraction topography and scanning electron microscopy. The electronic structure of CMT is very similar to that of CZT, with shallow traps, A-centers, Cd vacancies, deep levels, and Te antisites. The 1.1-eV deep level, revealed by PL in earlier studies of CZT and CdTe, were attributed to dislocation-induced defects. In our I-DLTS measurements, the 1.1-eV traps showed different activation energies with applied bias voltage and an exponential dependence on the trap-filling time, which are typical characteristics of dislocation-induced defects. We propose a new defect-trap model for indium-doped CMT crystals.

K Kim; A Bolotinikov; G Camarda; R Gul; A Hossain; G Yang; Y Cui; R James

2011-12-31T23:59:59.000Z

451

REACTOR CONTROL MECHANISM  

DOE Patents (OSTI)

A quick-releasing mechanism is described which may be used to rapidiy drop a device supported from beneath during normal use, such as a safety rod in a nuclear reactor. In accordance with this invention an electrical control signal, such as may be provided by radiation detection or other alarm condition sensing devices, is delivered to an electromagnetic solenoid, the armature of which is coupled to an actuating mechanism. The solenoid is energized when the mechanism is in its upper or cocked position. In such position, the mechanism engages a plurality of retaining balls, forcing them outward into engagement with a shoulder or recess in a corresponding section of a tubular extension on the upheld device. When the control signal to the solenoid suddenly ceases, the armature drops out, allowing the actuating mechanism to move slightly but rapidly under the force of a compressed spring. The weight of the device will urge the balls inward against a beveled portion of the actuating mechanism and away from the engaging section on the tubular extension, thus allowing the upheld device to fall freely under the influence of gravity.

Lane, J.A.; Engberg, R.E.; Welch, J.M.

1959-05-12T23:59:59.000Z

452

Effect of Nickel Substitution on Defect Chemistry, Electrical Properties, and Dimensional Stability of Calcium-Doped Yttrium Chromite  

SciTech Connect

The effect of nickel substitution on defect chemistry, electrical properties, and dimensional stability of calcium-doped yttrium chromite was studied for use as an interconnect material in high temperature solid oxide fuel cells (SOFCs). The compositions of Y0.8Ca0.2Cr1-xNixO3? (x=0-0.15), prepared using the glycine nitrate process, showed single phase orthorhombic perovskite structures over a wide range of oxygen partial pressures (10^-17 atm ? pO2 ? 0.21 atm). X-ray diffraction (XRD) analysis indicated that most of the nickel ions replacing chromium ions are divalent and act as acceptor dopants, leading to a substantial increase in conductivity. In particular, the conductivity at 900 degree C in air increased from 10 S/cm to 34 S/cm with 15% nickel substitution, and an increase in charge carrier density was confirmed by Seebeck measurements. A point defect model was derived, and the relationship between electrical conductivity and oxygen partial pressure was successfully fitted into the proposed model. The defect modeling results indicated that nickel substitution improves the stability of calcium-doped yttrium chromite toward reduction and suppresses the oxygen vacancy formation, which results in significantly increased electrical conductivity in reducing environment. The electrical conductivity of Y0.8Ca0.2Cr0.85Ni0.15O3? at 900 degree C in reducing atmosphere (pO2=10^-17 atm) was 5.8 S/cm, which was more than an order of magnitude higher than that of Y0.8Ca0.2CrO3? (0.2 S/cm). Improved stability in reducing atmosphere was further confirmed by dilatometry measurements showing reduced isothermal "chemical" expansion, and the isothermal expansion in reducing atmosphere (pO2=10^-17 atm) at 900 degree C decreased from 0.07% for Y0.8Ca0.2CrO3? to 0.03% for Y0.8Ca0.2Cr0.85Ni0.15O3?. Based on these results, enhanced electrical performance and mechanical integrity is expected with nickel substitution on calcium-doped yttrium chromite in SOFC operating conditions.

Yoon, Kyung J.; Stevenson, Jeffry W.; Marina, Olga A.

2011-06-30T23:59:59.000Z

453

Successful persuasive technology for behavior reduction: mapping to foggs gray behavior grid  

Science Conference Proceedings (OSTI)

This study evaluates 24 persuasive technologies that achieved statistically significant behavior reduction across a variety of domains. The purpose of this research was to map the 24 persuasive technology studies across the Gray Behaviors (decrease behavior) ... Keywords: behavior grid, behavior reduction, persuasive design, persuasive technology

Susan Shepherd Ferebee

2010-06-01T23:59:59.000Z

454

Jar mechanism energizer  

Science Conference Proceedings (OSTI)

An energizer for use with a jar mechanism incorporated on inner and outer bodies in a well string to assist the jar mechanism in delivering an upward jar to the well string includes longitudinally spaced seal means between the inner and outer bodies forming a chamber for receiving a compressible medium therein. A differential area formed on one of the bodies within the compressible medium chamber compresses a compressible medium in the chamber as the well string is lowered to position the inner and outer bodies so that the jar mechanism is actuated to restrain relative longitudinal movement between the inner and outer bodies to an extended position whereby a pull force may be developed in the well string in one of the bodies. The differential area is responsive to the compressed gas in the chamber to assist the jar mechanism in applying an upward jarring force when the jar mechanism, in response to a predetermined pull force in the well string, releases the bodies for contact to apply an upward force to the well string.

Webb, D. D.; Anderson, E. A.

1985-10-08T23:59:59.000Z

455

Jar mechanism accelerator  

SciTech Connect

This patent describes an accelerator for use with a jar mechanism in a well pipe string to enhance the jarring impact delivered to a stuck object wherein the jar mechanism includes inner and outer members for connection, respectively, between the well pipe string the stuck object. The jar mechanism members are constructed to (1) restrict relative longitudinal movement therebetween to build up energy in the well pipe string and accelerator and then (2) to release the jar mechanism members for unrestrained, free relative longitudinal movement therebetween to engage jarring surfaces on the jar mechanism members for delivering a jarring impact to the stuck object. The accelerator includes: inner and outer telescopically connected members relatively movable longitudinally to accumulate energy in the accelerator; the inner and outer accelerator members each having means for connecting the accelerator in the well pipe string; means associated with the inner and outer members for initially accomodating a predetermined minimum length of unrestrained, free relative longitudinal movement between the inner and outer accelerator members.

Anderson, E.A.; Webb, D.D.

1989-07-11T23:59:59.000Z

456

Deactivation Mechanism and Hole Scavenging in Heterostructured ...  

Science Conference Proceedings (OSTI)

Development of ZnO/MgO/p-Si Heterostructures for Pure UV Light Emitting Diode with Carrier Blocking Layer Effect of Annealing and Additives on Defects and...

457

Microstructural and Mechanical Property Changes in Ion Irradiated Tunsgten  

E-Print Network (OSTI)

Sustainable fusion power is within reach; however, more research is needed in the field of material science and engineering. One critical component of a fusion reactor is the plasma facing material. Very little literature exists on the sustainability of tungsten as a plasma facing material (PFM). During operation, PFM must withstand harsh conditions with combined effects from high temperature, mechanical stress, irradiation, transmutation, and the production of hydrogen (H) and helium (He) from nuclear reactions. Therefore, this thesis will focus on co-implantation of H and He into tungsten to investigate the mechanical and microstructural material response. For the first part of this study, Molecular Dynamics (MD) was used to qualitatively understand defect migration and mechanical property changes in tungsten. A Brinell hardness test was simulated using MD in tungsten to study the dependence on void size and void density hardness. It was found that hardness changes vary as the square root of the void size and void density. Also the movement of dislocations and its interaction with voids were investigated. For the second part of the study, H and He were co-implanted into tungsten to look at the mechanical and microstructural changes. Hardness changes were measured using a nano-indenter ex-situ on post-irradiated specimen. Results show that the hardness of tungsten after co-implantation is proportional to the square root of the fluence. Additionally, the microstructure of irradiated tungsten samples was investigated by using a Transmission Electron Microscope (TEM). It was observed that the defect microstructure in tungsten, after co-implantation, is quite complex, with a number of intriguing features, such as the presence of the nano-bubbles and dislocation loops. Also it was observed that there was an effect that H has on the nucleation of He nano-bubbles. The results from this work suggest that the effect of co-implanting H and He into tungsten is crucial to fully understand its viability as a PFM.

General, Michael

2013-05-01T23:59:59.000Z

458

Fundamental Scratch Behavior of Styrene-Acrylonitrile Random Copolymers  

E-Print Network (OSTI)

The present study employs a standardized progressive load scratch test (ASTM D7027/ISO 19252) to investigate the fundamental physical and mechanistic origins of scratch deformation in styrene-acrylonitrile (SAN) random copolymers. Previous findings from numerical simulation using finite element methods are used to establish correlation between mechanical properties and key scratch deformation mechanisms of the SAN model systems. For SAN, the acrylonitrile (AN) content and molecular weight (MW) can be changed to alter mechanical properties such as tensile strength and ductility. The key scratch deformation mechanisms are identified as: scratch groove formation, scratch visibility, periodic micro-cracking and plowing. Groove formation has been correlated to the secant modulus at the compressive yield point while micro-cracking and plowing are related to the tensile strength of the material. The fundamentals and physical origins of scratch visibility are discussed. It is explained how unbiased evaluation is accomplished by means of an automatic digital image analysis software package (ASV). Frictional behavior and the effects of scratch speed and moisture absorption are also addressed. Increasing the AN content and/or the MW of the SAN random copolymers generally enhances the scratch resistance of the material with regard to the onset of the key deformation mechanisms. Increasing the scratch speed increases the brittleness of the material, resulting in failure at lower applied loads. Moisture absorption increases with AN content and imparts a degree of plasticization as the moisture diffuses into the sub-surface. This plasticization initially results in a degradation of scratch resistance with respect to the key deformation mechanisms, but then, after saturation, the moisture on the surface provides lubrication and improves the scratch resistance. It is important to note that polymers are fundamentally different in nature, but the findings of this study serve as an important stepping stone down the path to a deeper understanding of polymer scratch behavior.

Browning, Robert Lee

2010-08-01T23:59:59.000Z

459

Experimental unsaturated soil mechanics  

E-Print Network (OSTI)

In this general report, experimental systems and procedures of investigating the hydro-mechanical behaviour of unsaturated soils are presented. The water retention properties of unsaturated soils are commented and linked to various physical parameters and properties of the soils. Techniques of controlling suction are described together with their adaptation in various laboratory testing devices. Some typical features of the mechanical behaviour of unsaturated soils are presented within an elasto-plastic framework. An attempt to describe the numerous and significant recent advances in the investigation of the behaviour of unsaturated soils, including the contributions to this Conference, is proposed.

Delage, Pierre

2008-01-01T23:59:59.000Z

460

Breakthrough in fracture mechanics  

SciTech Connect

Fracture mechanics, the science of calculating material characteristics, stress, and flaws in plant equipment to evaluate structural integrity, usually spares the owners of nuclear power plants unnecessary expense. Instead of replacing equipment prematurely or waiting for costly, unscheduled materials failures that can take months to repair and cost thousands of dollars a day for replacement power, utilities use fracture mechanics techniques to carefully consider their options. If analyses show repair is unnecessary, plant operation can confidently be resumed. If repair is required, it can either be done immediately or, if deferrable, be scheduled for a later, more convenient outage.

Lihach, N.

1981-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "defects mechanical behavior" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Emergent Run-and-Tumble Behavior in a Simple Model of Chlamydomonas with Intrinsic Noise  

E-Print Network (OSTI)

Recent experiments on the green alga Chlamydomonas that swims using synchronized beating of a pair of flagella have revealed that it exhibits a run-and-tumble behavior similar to that of bacteria such as E. Coli. Using a simple purely hydrodynamic model that incorporates a stroke cycle and an intrinsic Gaussian white noise, we show that a stochastic run-and-tumble behavior could emerge, due to the nonlinearity of the combined synchronization-rotation-translation dynamics. This suggests the intriguing possibility that the alga might exploit nonlinear mechanics---as opposed to sophisticated biochemical circuitry as used by bacteria---to control its behavior.

Rachel R. Bennett; Ramin Golestanian

2012-11-14T23:59:59.000Z

462

Irradiation Effects on Human Cortical Bone Fracture Behavior  

NLE Websites -- All DOE Office Websites (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

463

Irradiation Effects on Human Cortical Bone Fracture Behavior  

NLE Websites -- All DOE Office Websites (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

464

Irradiation Effects on Human Cortical Bone Fracture Behavior  

NLE Websites -- All DOE Office Websites (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

465

Irradiation Effects on Human Cortical Bone Fracture Behavior  

NLE Websites -- All DOE Office Websites (Extended Search)

Irradiation Effects on Human Irradiation Effects on Human Cortical Bone Fracture Behavior Irradiation Effects on Human Cortical Bone Fracture Behavior Print Wednesday, 28 July 2010 00:00 Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

466

Irradiation Effects on Human Cortical Bone Fracture Behavior  

NLE Websites -- All DOE Office Websites (Extended Search)

Irradiation Effects on Human Cortical Bone Fracture Behavior Print Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic framework to understand the changes taking place on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and/or tomography, is a popular method of investigating micrometer deformation and fracture behavior in bone. However, the role that irradiation plays in these high-exposure experiments, and how it affects the properties of bone tissue, are not yet fully understood. A team of researchers led by Robert O. Ritchie at the Lawrence Berkeley National Laboratory and the University of California, Berkeley used synchrotron radiation micro-tomography at Advanced Light Source Beamline 8.3.2 to investigate changes in crack path and toughening mechanisms in human cortical bone with increased exposure to radiation, finding that exposure to high levels of irradiation can lead to drastic losses in strength, ductility, and toughness.

467

Polaron Behavior in CMR Manganites  

NLE Websites -- All DOE Office Websites (Extended Search)

Polaron Behavior in CMR Manganites Print Polaron Behavior in CMR Manganites Print Spintronic devices manipulate electron spin to sense magnetic fields, store information, or perform logical operations. Colossal magnetoresistive (CMR) manganites are a class of materials under study for future spintronic applications such as nonvolatile magnetic computer memory (MRAM). Researchers have recently used several soft x-ray spectroscopies at the ALS to study a prototypical CMR manganite as it was heated past its Curie temperature-the point at which the material ceases to be magnetic. They were able to observe the formation of polarons: electrons whose interaction with the lattice creates a deformation (energy well) that traps the electron, as a pocket on a pool table traps a billiard ball. For the first time, this provided a direct look inside polaron formation in a CMR material, indicating that electron localization as polarons is a defining characteristic of all CMR materials.

468

Polaron Behavior in CMR Manganites  

NLE Websites -- All DOE Office Websites (Extended Search)

Polaron Behavior in CMR Manganites Print Polaron Behavior in CMR Manganites Print Spintronic devices manipulate electron spin to sense magnetic fields, store information, or perform logical operations. Colossal magnetoresistive (CMR) manganites are a class of materials under study for future spintronic applications such as nonvolatile magnetic computer memory (MRAM). Researchers have recently used several soft x-ray spectroscopies at the ALS to study a prototypical CMR manganite as it was heated past its Curie temperature-the point at which the material ceases to be magnetic. They were able to observe the formation of polarons: electrons whose interaction with the lattice creates a deformation (energy well) that traps the electron, as a pocket on a pool table traps a billiard ball. For the first time, this provided a direct look inside polaron formation in a CMR material, indicating that electron localization as polarons is a defining characteristic of all CMR materials.

469

EFFECTS OF ORAL MOTOR IMITATION BEHAVIORAL FLUENCY ON MEASURES OF ECHOIC BEHAVIOR.  

E-Print Network (OSTI)

??The proposed study examined the effects of behavioral fluency in oral motor imitation on echoic behavior in elementary children with autism. A multiple baseline multiple (more)

Garner, Dana

2011-01-01T23:59:59.000Z

470

STATISTICAL MECHANICS AND FIELD THEORY  

E-Print Network (OSTI)

1. L. 1. Schiff, Quantum Mechanics, third edition (McGraw-two-dimensional quantum mechanics problem vith a potential,Theory Methods to Statistical Mechanics Chapter I The Use of

Samuel, S.A.

2010-01-01T23:59:59.000Z

471

DEPARTMENT OF MECHANICAL ENGINEERING  

E-Print Network (OSTI)

the Chair Advanced Power Systems Research Group Engineering Education Innovation Research Group Mechanics of MultiScale Materials Research Group MultiScale Systems and Sensors Research Group Space Systems Research Group Sustainable Manufacturing and Design Research Group Faculty Profiles Michigan

Endres. William J.

472

MECHANICAL TEST LAB CAPABILITIES  

E-Print Network (OSTI)

MECHANICAL TEST LAB CAPABILITIES · Static and cyclic testing (ASTM and non-standard) · Impact drop testing · Slow-cycle fatigue testing · High temperature testing to 2500°F · ASTM/ Boeing/ SACMA standard testing · Ability to design and fabricate non-standard test fixtures and perform non-standard tests

473

SAFETY-MECHANICAL STANDARDS  

SciTech Connect

Hanford Atomic Production Operation specification guides and standards for plumbing, chemical ngineering, mechanical engineering, sanitary engineering, exhaust systems, steam engineering, stainless steel, dry boxes, thermal insulation, filtration, and materials testing are presented. Details of this manual are given in TID-4100 (Suppl.). (N.W.R.)

1964-10-31T23:59:59.000Z

474

Higgs Mechanism for Gravitons  

E-Print Network (OSTI)

Just like the vector gauge bosons in the gauge theories, it is now known that gravitons acquire mass in the process of spontaneous symmetry breaking of diffeomorphisms through the condensation of scalar fields. The point is that we should find the gravitational Higgs mechanism such that it results in massive gravity in a flat Minkowski space-time without non-unitary propagating modes. This is usually achieved by including higher-derivative terms in scalars and tuning the cosmological constant to be a negative value in a proper way. Recently, a similar but different gravitational Higgs mechanism has been advocated by Chamseddine and Mukhanov where one can relax the negative cosmological constant to zero or positive one. In this work, we investigate why the non-unitary ghost mode decouples from physical Hilbert space in a general space-time dimension. Moreover, we generalize the model to possess an arbitrary potential and clarify under what conditions the general model exhibits the gravitational Higgs mechanism. By searching for solutions to the conditions, we arrive at two classes of potentials exhibiting gravitational Higgs mechanism. One class includes the model by Chamseddine and Mukhanov in a specific case while the other is completely a new model.

Ichiro Oda

2010-03-07T23:59:59.000Z

475

Fractals and quantum mechanics  

Science Conference Proceedings (OSTI)

A new application of a fractal concept to quantum physics has been developed. The fractional path integrals over the paths of the Lvy flights are defined. It is shown that if fractality of the Brownian trajectories leads to standard quantum mechanics

Nick Laskin

2000-01-01T23:59:59.000Z

476

Molecular structure, mechanical behavior and failure mechanism of the C-terminal cross-link domain in type I collagen  

E-Print Network (OSTI)

Collagen is a key constituent in structural materials found in biology, including bone, tendon, skin and blood vessels. Here we report a first molecular level model of an entire overlap region of a C-terminal cross-linked ...

Uzel, Sebastien Guy Marcel

477

Transition from supercapacitor to battery behavior in electrochemical energy storage  

Science Conference Proceedings (OSTI)

In this paper the storage of electrochemical energy in battery, supercapacitor, and double-layer capacitor devices is considered. A comparison of the mechanisms and performance of such systems enables their essential features to be recognized and distinguished, and the conditions for transition between supercapacitor and battery behavior to be characterized. Supercapacitor systems based on two-dimensional underpotential deposition reactions are highly reversible and their behavior arises from the pseudocapaccitance associated with potential-dependence of two-dimensional coverage of electroactive adatoms on an electrode substrate surface. Such capacitance can be 10-100 times the double-layer capacitance of the same electrode area. An essential fundamental difference from battery behavior arises because, in such systems, the chemical and associated electrode potentials are a continuous function of degree of charge, unlike the thermodynamic behavior of single-phase battery reactants. Quai-two-dimensional systems, such as hyperextended hydrous RuP{sub 2}, also exhibit large pseudocapacitance which, in this case, is associated with a sequence of redox redox processes that are highly reversible.

Conway, B.E. (Ottawa Univ., ON (Canada). Dept. of Chemistry)

1991-06-01T23:59:59.000Z

478

Thermal Degradation Behavior of Siloxane Elastomer Impregnated Carbon Nanotube Areogel Networks  

DOE Green Energy (OSTI)

A novel class of nanoporous graphitic carbon foams has been synthesized. Unprecedented properties - electrically conductive, thermally stable (> 1000 C), and mechanically robust. Improved transport properties (DWNT-CA, SWNT-CA) - greater than 100% enhancement in thermal conductivity, 100-400% improvement in electrical conductivity. Rich mechanical deformation behavior (SWNT-CA) - stiff ({approx}100% improvement of elastic modulus), energy dissipation, fracture toughness, and fatigue behavior. Implications for energy-related technologies - hydrogen storage, fusion and fission energy, catalysis, electrochemical energy storage, and composites with foam scaffolds.

Lewicki, J P; Worsley, M A

2010-12-13T23:59:59.000Z

479

Automated real-time detection of defects during machining of ceramics  

DOE Patents (OSTI)

Apparatus for the automated real-time detection and classification of defects during the machining of ceramic components employs an elastic optical scattering technique using polarized laser light. A ceramic specimen is continuously moved while being machined. Polarized laser light is directed onto the ceramic specimen surface at a fixed position just aft of the machining tool for examination of the newly machined surface. Any foreign material near the location of the laser light on the ceramic specimen is cleared by an air blast. As the specimen is moved, its surface is continuously scanned by the polarized laser light beam to provide a two-dimensional image presented in real-time on a video display unit, with the motion of the ceramic specimen synchronized with the data acquisition speed. By storing known "feature masks" representing various surface and sub-surface defects and comparing measured defects with the stored feature masks, detected defects may be automatically characterized. Using multiple detectors, various types of defects may be detected and classified.

Ellingson, William A. (Naperville, IL); Sun, Jiangang (Westmont, IL)

1997-01-01T23:59:59.000Z

480

Automated real-time detection of defects during machining of ceramics  

DOE Patents (OSTI)

Apparatus for the automated real-time detection and classification of defects during the machining of ceramic components employs an elastic optical scattering technique using polarized laser light. A ceramic specimen is continuously moved while being machined. Polarized laser light is directed onto the ceramic specimen surface at a fixed position just aft of the machining tool for examination of the newly machined surface. Any foreign material near the location of the laser light on the ceramic specimen is cleared by an air blast. As the specimen is moved, its surface is continuously scanned by the polarized laser light beam to provide a two-dimensional image presented in real-time on a video display unit, with the motion of the ceramic specimen synchronized with the data acquisition speed. By storing known ``feature masks`` representing various surface and sub-surface defects and comparing measured defects with the stored feature masks, detected defects may be automatically characterized. Using multiple detectors, various types of defects may be detected and classified. 14 figs.

Ellingson, W.A.; Sun, J.

1997-11-18T23:59:59.000Z

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481

Studies on relative effects of charged and neutral defects in hydrogenated amorphous silicon  

DOE Green Energy (OSTI)

This report covers the third year of a continuing research study to understand the relative importance of charged and neutral defects in amorphous silicon. The objective of the study is to explore the electronic structure, including neutral and charged defects, an optoelectronic effects including the formation of Staebler-Wronski defects. The study concentrated on exploring electroluminescence experimentally and interpreting the results employing a simple guiding model. The simple guiding model assumes an exponential density of states and recombination rate constants (radiative and non-radiative) which are governed by hopping transitions. Measurements were also made as a function of photodegradation of the material. The results implicate that the radiative recombination processes are not distant pair tunneling but rather results from electrons hopping down due to the coulomb interactions. Preliminary experiments have been made on the effect of photodegradation on transient space charge limited currents in n/i/n structures. These experiments can directly yield information on the occupied defects centers induced by the photodegradation and are not a result of recombination processes. To date the results seems to be consistent with a picture which places the doubly occupied defects at quite a high energy ({approx equal} 0.4 e.v. below the conduction band).

Silver, M. (North Carolina Univ., Chapel Hill, NC (United States))

1992-02-01T23:59:59.000Z

482

CHARACTERIZATION OF PD IMPURITIES AND TWIN BOUNDARY DEFECTS IN DETECTOR GRADE CDZNTE CRYSTALS  

Science Conference Proceedings (OSTI)

Synthetic CdZnTe or ''CZT'' crystals are highly suitable for {gamma}-spectrometers operating at the room temperature. Secondary phases (SP) in CZT are known to inhibit detector performance, particularly when they are present in large numbers or dimensions. These SP may exist as voids or composites of non-cubic phase metallic Te layers with bodies of polycrystalline and amorphous CZT material and voids. Defects associated with crystal twining may also influence detector performance in CZT. Using transmission electron microscopy, we identify two types of defects that are on the nano scale. The first defect consists of 40 nm diameter metallic Pd/Te bodies on the grain boundaries of Te-rich composites. Although the nano-Pd/Te bodies around these composites may be unique to the growth source of this CZT material, noble metal impurities like these may contribute to SP formation in CZT. The second defect type consists of atom-scale grain boundary dislocations. Specifically, these involve inclined ''finite-sized'' planar defects or interfaces between layers of atoms that are associated with twins. Finite-sized twins may be responsible for the subtle but observable striations that can be seen with optical birefringence imaging and synchrotron X-ray topographic imaging.

Duff, M.

2011-06-22T23:59:59.000Z

483

Impact of hydrogen and oxygen defects on the lattice parameter of chemical vapor deposited zinc sulfide  

SciTech Connect

The lattice parameter of cubic chemical vapor deposited (CVD) ZnS with measured oxygen concentrations < 0.6 at.% and hydrogen impurities of < 0.015 at.% have been measured and found to vary between -0.10% and +0.09% relative to the reference lattice parameter (5.4093 ) of oxygen-free cubic ZnS as reported in the literature. Defects other than substitutional O must be invoked to explain these observed volume changes. The structure and thermodynamic stability of a wide range of native and impurity induced defects in ZnS have been determined by Ab initio calculations. Lattice contraction is caused by S-vacancies, substitutional O on S sites, Zn vacancies, H in S vacancies, peroxy defects, and dissociated water in S-vacancies. The lattice is expanded by interstitial H, H in Zn vacancies, dihydroxy defects, interstitial oxygen, Zn and [ZnHn] complexes (n=1,,4), interstitial Zn, and S2 dumbbells. Oxygen, though present, likely forms substitutional defects for sulfur resulting in lattice contraction rather than as interstitial oxygen resulting in lattice expansion. It is concluded based on measurement and calculations that excess zinc atoms either at anti-sites (i.e. Zn atoms on S-sites) or possibly as interstitial Zn are responsible for the relative increase of the lattice parameter of commercially produced CVD ZnS.

McCloy, John S.; Wolf, Walter; Wimmer, Erich; Zelinski, Brian

2013-01-09T23:59:59.000Z

484

Quantum Mechanics and Black Holes  

E-Print Network (OSTI)

This paper discusses the existence of black holes from the foundations of quantum mechanics. It is found that quantum mechanics rule out a possible gravitational collapse.

Jose N. Pecina-Cruz

2005-11-11T23:59:59.000Z

485

Essays on genetic variation and economic behavior  

E-Print Network (OSTI)

This thesis is a collection of papers in which behavior genetic methods are used to shed light on individual differences in economic preferences, behaviors and outcomes. Chapter one uses the classical twin design to provide ...

Cesarini, David Alexander

2010-01-01T23:59:59.000Z

486

Essays on malpractice law and physician behavior  

E-Print Network (OSTI)

This dissertation contributes to an understanding of the manner in which various dimensions of malpractice law shape physician behavior and how this behavior, in turn, impacts health outcomes. In Chapter 1, I explore the ...

Frakes, Michael (Michael D.)

2009-01-01T23:59:59.000Z

487

Behavioral simulations in MapReduce  

Science Conference Proceedings (OSTI)

In many scientific domains, researchers are turning to large-scale behavioral simulations to better understand real-world phenomena. While there has been a great deal of work on simulation tools from the high-performance computing community, behavioral ...

Guozhang Wang; Marcos Vaz Salles; Benjamin Sowell; Xun Wang; Tuan Cao; Alan Demers; Johannes Gehrke; Walker White

2010-09-01T23:59:59.000Z

488

Undefined behavior: what happened to my code?  

Science Conference Proceedings (OSTI)

System programming languages such as C grant compiler writers freedom to generate efficient code for a specific instruction set by defining certain language constructs as undefined behavior. Unfortunately, the rules for what is undefined behavior are ...

Xi Wang; Haogang Chen; Alvin Cheung; Zhihao Jia; Nickolai Zeldovich; M. Frans Kaashoek

2012-07-01T23:59:59.000Z

489

9.20 Animal Behavior, Fall 2001  

E-Print Network (OSTI)

This course will sample the broad diversity of animal behavior and the behavioral adaptation of animals to the environments in which they live. This will include discussion of both field observations and controlled laboratory ...

Ramus, Seth Jacob

490

Dynamic coupling between a multistable defect pattern and flow in nematic liquid crystals confined in a porous medium  

E-Print Network (OSTI)

When a nematic liquid crystal is confined in a porous medium with strong anchoring conditions, topological defects, called disclinations, are stably formed with numerous possible configurations. Since the energy barriers between them are large enough, the system shows multistability. Our lattice Boltzmann simulations demonstrate dynamic couplings between the multistable defect pattern and the flow in a regular porous matrix. At sufficiently low flow speed, the topological defects are pinned at the quiescent positions. As the flow speed is increased, the defects show cyclic motions and nonlinear rheological properties, which depend on whether or not they are topologically constrained in the porous networks. In addition, we discovered that the defect pattern can be controlled by controlling the flow. Thus, the flow path is recorded in the porous channels owing to the multistability of the defect patterns.

Takeaki Araki

2012-12-17T23:59:59.000Z

491

Effect of stoichiometry on the dielectric properties and soft mode behavior of strained epitaxial SrTiO3 thin films on DyScO3 substrates  

Science Conference Proceedings (OSTI)

The effect of stoichiometry on the dielectric properties and soft mode behavior of strained epitaxial Sr1-xTiO3 films grown on DyScO3 substrates is reported. Direct comparisons between nominally stoichiometric and non-stoichiometric films have been performed through measurements of lattice parameters, temperature-dependent permittivities, second harmonic generation, and terahertz dielectric spectra. The nominally stoichiometric film shows dispersion-free low-frequency permittivity with a 23 sharp maximum and pronounced soft mode behavior. Our results suggest that strained perfectlystoichiometric SrTiO3 films should not show relaxor behavior and that relaxor behavior emergesfrom defect dipoles that arise from non-stoichiometry in the highly polarizable strained SrTiO3 matrix

Lee, Che-Hui [Pennsylvania State University, University Park, PA; Skoromets, Volodymyr [Institute of Physics, Czech Republic; Biegalski, Michael D [ORNL; Lei, Shiming [Pennsylvania State University, University Park, PA; Haislmaier, Ryan [Pennsylvania State University, University Park, PA; Uecker, Reinhard [Leibniz Institute for Crystal Growth (IKZ); Bernhagen, Margitta [Leibniz Institute for Crystal Growth (IKZ); Xi, Xiaoxing [Temple University; Gopalan, Venkatraman [Pennsylvania State University, University Park, PA; Marti, Xavier [Institute of Physics, Czech Republic; Kamba, Stanislav [Institute of Physics, Czech Republic; Kuzel, Petr [Institute of Physics, Czech Republic; Schlom, Darrell [Cornell University

2013-01-01T23:59:59.000Z

492

The role of oxygen-related defects and hydrogen impurities in HfO2 and ZrO2  

Science Conference Proceedings (OSTI)

We investigate the properties of oxygen-related defects and hydrogen impurities in monoclinic HfO"2 and ZrO"2 using first-principles calculations based on a hybrid functional. We examine how the formation energy of these defects depend on the Fermi level ... Keywords: Defects in semiconductors, First-principles calculations, HfO2, High-k dielectrics, Hydrogen impurities, Oxygen interstitial, Oxygen vacancy, Sources of fixed charge, ZrO2

J. L. Lyons; A. Janotti; C. G. Van de Walle

2011-07-01T23:59:59.000Z

493

Predicting mobile call behavior via subspace methods  

Science Conference Proceedings (OSTI)

We investigate behavioral prediction approaches based on subspace methods such as principal component analysis (PCA) and independent component analysis (ICA). Moreover, we propose a personalized sequential prediction approach to predict next day behavior ... Keywords: behavior prediction, eigenbehavior, independent component analysis, principal component analysis, sequential prediction

Peng Dai; Wanqing Yang; Shen-Shyang Ho

2013-04-01T23:59:59.000Z

494

Multifractal scaling behavior analysis for existing dams  

Science Conference Proceedings (OSTI)

The fractal theory was used to describe long term behavior of dam structures by means of determining (mono-) fractal exponents. Many records do not exhibit a simple monofractal scaling behavior, which can be accounted for by a single scaling exponent. ... Keywords: Dam, Long term behavior, Multifractal detrended fluctuation analysis, Observation time series

Huaizhi Su, Zhiping Wen, Feng Wang, Bowen Wei, Jiang Hu

2013-09-01T23:59:59.000Z

495

A Theoretical Study of the Magnetic Structure of Bulk Iron with Radiation Defects  

SciTech Connect

A fundamental understanding of the radiation damage effects in solids is of great importance in assisting the development of improved materials with ultra-high strength, toughness, and radiation resistance for nuclear energy applications. In this presentation, we show our recent theoretical investigation on the magnetic structure evolution of bulk iron in the region surrounding the radiation defects. We applied the locally self-consistent multiple scattering method (LSMS), a linear scaling ab-initio method based on density functional theory with local spin density approximation, to the study of the magnetic structure in a low energy cascade in a 10,000-atom sample for a series of time steps for the evolution of the defects. The primary damage state and the evolution of all defects in the sample were simulated using molecular dynamics with empirical, embedded-atom inter-atomic potentials. We also discuss the importance of thermal effect on the magnetic structure evolution.

Wang, Yang [Pittsburgh Supercomputing Center; Stoller, Roger E [ORNL; Rusanu, Aurelian [ORNL; Nicholson, Don M [ORNL; Eisenbach, Markus [ORNL; Stocks, George Malcolm [ORNL

2011-01-01T23:59:59.000Z