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1

Probability distribution of von Mises stress in the presence of pre-load.  

SciTech Connect

Random vibration under preload is important in multiple endeavors, including those involving launch and re-entry. There are some methods in the literature to begin to address this problem, but there is nothing that accommodates the existence of preloads and the necessity of making probabilistic statements about the stress levels likely to be encountered. An approach to achieve to this goal is presented along with several simple illustrations.

Segalman, Daniel Joseph; Field, Richard V., [Sandia National Laboratories, Albuquerque, NM; Reese, Garth M. [Sandia National Laboratories, Albuquerque, NM

2013-04-01T23:59:59.000Z

2

Martin Löf - Solovay - Chaitin Axiom of Reduction versus Von Mises - Church Axiom of Reduction  

E-Print Network (OSTI)

Under the assumption that the quantum random number generator Quantis by Id Quantique is a fair quantum coin, experimental indications of the fact that independent tosses of a quantum coin don't pass the Iterated Logarithm Randomness' Test are shown. The consequential observed experimental violation of the Martin L\\"{o}f - Solovay - Chaitin Axiom of Reduction of Quantum Mechanics is then interpreted as the indication of the necessity of replacing it with the weaker Von Mises - Church Axiom of Reduction whose Game Theoretic meaning is explained.

Gavriel Segre

2009-04-18T23:59:59.000Z

3

Multi-Fiber Reconstruction from DW-MRI using a Continuous Mixture of von Mises-Fisher Distributions  

E-Print Network (OSTI)

Multi-Fiber Reconstruction from DW-MRI using a Continuous Mixture of von Mises-Fisher Distributions the Diffusion Weighted Magnetic Resonance (DW-MR) signal at each lattice point using a novel continuous mixture real DW-MRI data from rat brain and optic chiasm. 1. Introduction Since the first publication

Kumar, Ritwik

4

Discussion: John von Neumann - A Case Study of Scientific Creativity  

Science Conference Proceedings (OSTI)

Edward Teller assesses von Neumann's influence on the development of mathematics, especially of his work on representation theory of noncompact groups. He stresses von Neumann's early realization of the significance of computers. Wigner's recollections ...

W. Aspray; P. Horvath; D. Nagy; E. Teller; N. Vonneuman; E. P. Wigner

1989-09-01T23:59:59.000Z

5

Definition: DC Resistivity Survey (Mise-Á-La-Masse) | Open Energy...  

Open Energy Info (EERE)

Mise--La-Masse) Jump to: navigation, search Dictionary.png DC Resistivity Survey (Mise--La-Masse) The Mise--La-Masse technique is variation of a Direct-Current Resistivity...

6

Multi-fiber Reconstruction from DW-MRI using a Continuous Mixture of Hyperspherical von  

E-Print Network (OSTI)

Multi-fiber Reconstruction from DW-MRI using a Continuous Mixture of Hyperspherical von Mises Magnetic Resonance Imaging (DW-MRI), arguably one of the most important imaging inventions of the twentieth geometries such as fiber crossings ( [21, 17, 6]) and connectivity of different brain regions ([8]). DW

Kumar, Ritwik

7

Untersuchungen über Bildung von Komplexen von ...  

Science Conference Proceedings (OSTI)

Monatshefte fiir Chemie 109, 1383--1391 (1978) Monatsheftef6rcbemie. 9 by Springer-Verlag 1978. Untersuchungen iiber Bildung von Komplexen von Arylami-.

8

Das Ausschlussprinzip von Pauli  

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

knnen. Das wird das Ausschlussprinzip von Pauli genannt. Es erklrt, warum es Chemie geben kann. Aber spter hat man entdeckt, dass es eine Klasse von Teilchen gibt, fr...

9

DC Resistivity Survey (Mise-Á-La-Masse) | Open Energy Information  

Open Energy Info (EERE)

Mise-Á-La-Masse) Mise-Á-La-Masse) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: DC Resistivity Survey (Mise-Á-La-Masse) Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electrical Profiling Configurations Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal: Resistivity influenced by temperature Dictionary.png

10

Alexander von Scheven  

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

von Scheven Darmstadt University of Technology, Germany This speaker was a visiting speaker who delivered a talk or talks on the date(s) shown at the links below. This speaker is...

11

Mise en correspondance par correlation avec prise en compte des occultations  

E-Print Network (OSTI)

Mise en correspondance par corr´elation avec prise en compte des occultations Occlusions handling cours de l'appariement, provient des occultations. C'est pourquoi le second objectif est de pr compte le probl`eme des occultations. Les r´esultats mettent en ´evidence la meilleure m´ethode qui

Chambon, Sylvie

12

Tagessttte fr Kinder von Bediensteten  

E-Print Network (OSTI)

von Bediensteten ist ein univer- sitätseigenes Betreuungsangebot, das in der Trägerschaft der INA.KINDER.GARTEN Jahren · eine Kindergartengruppe mit 25 Kindern im Alter von 3 Jahren bis zum Schuleintritt Die INA.KINDER.GARTEN

Huber, Patrick

13

Wegauskunfte in Munchen herausgegeben von  

E-Print Network (OSTI)

90, Ziel: Englischer Garten Startorientierung: N/W, Ausrichtung: S/O F Entschuldige, k¨onntest Du mir vielleicht sagen, wie ich von hier zum Englischen Garten komm'? A Ok..ok F Genau...also von hier jetzt zum Englischen Garten? A Ok, also du musst bis vorne zur Kreuzung, dann nach links auf die Arcisstra�e, dann

Kuehnlenz, Kolja

14

mise jour: 09/12/2009 Rapport de ma mission au Pakistan  

E-Print Network (OSTI)

1 mise à jour: 09/12/2009 Rapport de ma mission au Pakistan �cole de recherche CIMPA du 22 au 28://www.lums.edu.pk/> pour y donner une conférence dans le cadre de French Science Tour in Pakistan Science Tour in Pakistan. · Samedi 28 février, 8 exposés organisés par Juergen Herzog permettant à des

Waldschmidt, Michel

15

mise jour: 30/03/2009 Rapport de ma mission au Pakistan  

E-Print Network (OSTI)

1 mise à jour: 30/03/2009 Rapport de ma mission au Pakistan �cole de recherche CIMPA du 22 au 28://www.lums.edu.pk/> pour y donner une conférence dans le cadre de French Science Tour in Pakistan Science Tour in Pakistan. · Samedi 28 février, 8 exposés organisés par Juergen Herzog permettant à des

Waldschmidt, Michel

16

Tagessttte fr Kinder von Bediensteten  

E-Print Network (OSTI)

ist ein univer- sitätseigenes Betreuungsangebot, das in der Trägerschaft der INA.KINDER.GARTEN Südwest Kindergartengruppe mit 25 Kindern im Alter von 3 Jahren bis zum Schuleintritt Die INA.KINDER.GARTEN Südwest

Mayberry, Marty

17

Tragfähigkeit von Schraubradgetrieben mit Schraubrädern aus Sintermetall.  

E-Print Network (OSTI)

??Schraubradgetriebe mit gesinterten Schraubrädern stellen zur Werkstoffpaarung Stahl/Kunststoff eine kostengünstige Alternative dar, zu der bislang keine gesicherten Berechnungsverfahren vorliegen. Diese Arbeit untersucht die Tragfähigkeit von… (more)

Wendt, Timo

2008-01-01T23:59:59.000Z

18

Komplexe Polykondensation von Ethylenglykol in einem RFNiederdruckplasma zur Bildung  

E-Print Network (OSTI)

), Chemie von neuen Materialien (plasmagestützte Schichtabschei- dung), Optik (Lampen, Strahlungsquellen

Greifswald, Ernst-Moritz-Arndt-Universität

19

Algumas contribuic~oes de von Neumann  

E-Print Network (OSTI)

~ao aqui abor­ dadas: os m'etodos matem'aticos da mecâ??anica quâ??antica (von Neumann, 1932) (inclusive, 1957) e suas aplica¸c~oes `a mecâ??anica estat'istica (Ruelle, 1969); a teoria dos espa¸cos produto, os m'etodos da teoria erg'odica e suas aplica¸c~oes `a mecâ??anica cl'assica (Koopman--von Neumann

Kohayakawa, Yoshiharu

20

Produkte von a#nen Variet aten. Proposition 2.3.9. Das Tensorprodukt von RAlgebren hat folgende Eigenschaften  

E-Print Network (OSTI)

Produkte von a#nen VarietË? aten. Proposition 2.3.9. Das Tensorprodukt von R­Algebren hat folgende Eigenschaften: (a) R# R R ## = R ## . (b) R ## R R ## # -# R ### R R # , x# y ## y# x ist ein Isomorphismus von R­Algebren. (c) R[x 1 , . . . , x n ]# R R ## = R ## [x 1 , . . . , x n ]. (d) Ist I # R # ein Ideal

Hartl, Urs

Note: This page contains sample records for the topic "von mises stress" 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

Produkte von affinen Varietaten. Proposition 2.3.9. Das Tensorprodukt von R-Algebren hat folgende Eigenschaften  

E-Print Network (OSTI)

Produkte von affinen Variet¨aten. Proposition 2.3.9. Das Tensorprodukt von R-Algebren hat folgende Eigenschaften: (a) R R R = R . (b) R R R - R R R , x y y x ist ein Isomorphismus von R-Algebren. (c) R[x1, . . . , xn] R R = R [x1, . . . , xn]. (d) Ist I R ein Ideal, so ist (R /I) R R = (R R R )/I·(R R R ). (e

Hartl, Urs

22

Oviedo (WS 2007/2008) (von: Holger Herzog)  

E-Print Network (OSTI)

, Chemie, Physik, Mathematik) und den Campus Milan, wo die meisten von euch studieren werden. Dort sind aufgrund von Verständigungsproblemen geben sollte, Frau Blanco-Hölscher, spricht auch deutsch. Sie ist (in einem die EC-Karte zugeschickt wird. Also rechtzeitig vorher erledigen! Die Deutsche Bank hat eine

Greifswald, Ernst-Moritz-Arndt-Universität

23

Sraffa-von Neumann, linear programming  

E-Print Network (OSTI)

Johann Wolfgang Goethe-Universität, Frankfurt, GermanySummary This paper examines the empirical relevance of the capital controversy between the proponents of the classical and of the neoclassical paradigm in economics. Aggregate capital at the macroeconomic level is regarded as the sum of capital goods employed, measured in terms of normal prices. Hence the price model of Sraffa (1960) and the dual models of the price and quantity systems of von Neumann (1937) become the basis of the investigation. The capital controversy is concerned with consequence of the choice of the cost minimizing technique in the production system for the relationship between distribution and the value of capital. Theoretical examples are easily constructed which contradict the fundamental neoclassical hypothesis of an inverse relationship between the rate of profit and the intensity of capital, differentiating between aggregate and sectoral intensity. This paper for the first time presents empirical examples. To this end, the quantity system of the von Neumann model is here used to model spectra of techniques. 32 input-output tables from 9 countries of the OECD input-output data base serve as data. One input-output table represents one technique (production system). A spectrum of technique, or book of blueprints, consists of two input-output tables from the

Jel Classification C; Zonghie Han; Bertram Schefold; Fachbereich Wirtschaftswissenschaften

2005-01-01T23:59:59.000Z

24

Dendritische Polythioetherliganden zur Synthese von Goldnanopartikel-Oligonucleotid-Monokonjugaten.  

E-Print Network (OSTI)

??Basierend auf der Entwicklung des Rubigoldes als thermostabilem Marker für Biomoleküle wurden in dieser Arbeit Polythioether-Liganden zur Synthese von monofunktionalen Cluster-Oligonucleotid-Konjugaten (COK) entwickelt. Zum Aufbau… (more)

Mönninghoff, Sven

2009-01-01T23:59:59.000Z

25

TBH-0034- In the Matter of Casey von Bargen  

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

This Initial Agency Decision involves a whistleblower complaint filed by Mr. Casey von Bargen (also referred to as the complainant or the individual) under the Department of Energy (DOE) Contractor...

26

Von Ardenne Anlagentechnik GmbH | Open Energy Information  

Open Energy Info (EERE)

Germany Zip 1324 Sector Solar Product German equipment manufacturer of wafer-based and thin-film solar cells. References Von Ardenne Anlagentechnik GmbH1 LinkedIn Connections...

27

A new inequality for the von Neumann entropy  

E-Print Network (OSTI)

Strong subadditivity of von Neumann entropy, proved in 1973 by Lieb and Ruskai, is a cornerstone of quantum coding theory. All other known inequalities for entropies of quantum systems may be derived from it. Here we prove a new inequality for the von Neumann entropy which we prove is independent of strong subadditivity: it is an inequality which is true for any four party quantum state, provided that it satisfies three linear relations (constraints) on the entropies of certain reduced states.

Noah Linden; Andreas Winter

2004-06-22T23:59:59.000Z

28

Akzeptanz und Nutzung von Pay-TV und neuen Diensten - Springer  

Science Conference Proceedings (OSTI)

in der wissenschaftlichen Thematisierung von. Produkten stets präsent war. In erster Linie ist diese Publikation ein ernsthaftes Diskussionsan- gebot.

29

Infinitely many constrained inequalities for the von Neumann entropy  

E-Print Network (OSTI)

We exhibit infinitely many new, constrained inequalities for the von Neumann entropy, and show that they are independent of each other and the known inequalities obeyed by the von Neumann entropy (basically strong subadditivity). The new inequalities were proved originally by Makarychev et al. [Commun. Inf. Syst., 2(2):147-166, 2002] for the Shannon entropy, using properties of probability distributions. Our approach extends the proof of the inequalities to the quantum domain, and includes their independence for the quantum and also the classical cases.

Josh Cadney; Noah Linden; Andreas Winter

2011-07-04T23:59:59.000Z

30

Ernte von Phacelien: Ernst Merz vor einem sogenannten Rhizo-Lysimeter. Foto: ETH Fortsetzung auf Seite 3  

E-Print Network (OSTI)

- senschaften) Thomas Kempe, Thema ,,Management von wet- terinduzierten Risiken in der Energiewirtschaft

31

Botanischer Garten aktuell Was ist was? -Die Blten von Iris  

E-Print Network (OSTI)

Botanischer Garten aktuell Was ist was? - Die Blüten von Iris Mit knapp 300 Arten gehört die Familie der Iridaceae (Schwertliliengewächse). Als Garten- pflanzen sind sie jedem bekannt; in der Natur Garten: Iris-Beet in der Nähe des Mittelmeerbeets, Teich, Wasserbecken etc. - Abb. aus PAX, F. (1888

Reggelin, Michael

32

EINBLICKE Nr. 32 / Herbst 2000 Carl von Ossietzky Universitt Oldenburg  

E-Print Network (OSTI)

Energieerträge kompensiert. Wie bei der Windenergie- nutzung an Land wird ein Erfolg der Offshore-Nutzung jedoch Windenergie Von Detlev Heinemann und Hans-Peter Waldl Nur wenige neue Technologien haben in derart kurzer Zeit geführt wie die Nutzung der Windenergie. Dieser Beitrag will den aktuellen Stand sowie die zukünftige

Heinemann, Detlev

33

Globaler Wandel, Klimawandel und regionale Anpassung1 Hans von Storch  

E-Print Network (OSTI)

Interessen an Risiken (Schiff bau; offshore Aktivitäten) und Potentialen (Windenergie) und die �ffentlichkeit ­Sicherheit, Offshore Windenergie, Interpretation von Messungen, �lunfälle und chronische Belastungen://www.norddeutscherklimaatlas.de/). Typische Stakeholder haben zu tun mit Küsten schutz, Landwirtschaft, offshore Aktivitäten, Tourismus

von Storch, Hans

34

Von Kármán's Constant in Atmospheric Boundary Layer Flow: Reevaluated  

Science Conference Proceedings (OSTI)

A field experiment has been carried out with the specific objective in mind to determine the value of von Kármán's constant in atmospheric boundary layer flow, and also to investigate its possible dependence on the surface Rossby number Ro0. Data ...

Ulf Högström

1985-02-01T23:59:59.000Z

35

Reduce Stress!  

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

Stress! Stress! x Take a break every hour. Do some relaxation or stretching exercises or talk with someone about topics unrelated to work. Give your body and mind a rest. x Massage your hands and forearms several times a day with a vitamin E lotion. The massage will improve circulation and break up adhesions. Since you can't touch a keyboard until the lotion is absorbed, it also enforces a good break. x Massage the muscles in your neck working your way down from the skull to the shoulders, applying more force to the larger muscles as you go down. x Periodically evaluate your environment for ways to reduce stress. Try to keep your desk uncluttered so you can always find things. Make sure programs are set up correctly on the computer, and see if you can use a macro program to reduce

36

Volumenerhaltung von Billiards Im Folgenden betrachten wir ein Orbitstck, so dass der Punkt (s, )  

E-Print Network (OSTI)

von (s, ) abhängige Variable ist. Wenn wir die Koordinaten umschreiben mittels r := - cos und analog r := - cos , dann vereinfachen sich die Gleichungen der Erzeugendenfunktion: s H(s, s ) = r , s H(s, s ) = -r. Wenn dann wie vorhin (s , ) das Bild unter f von (s, ) ist, dann können wir die erste Gleichung

Gunesch, Roland

37

Press Release Von Roll Inova to build the UK's largest energy-from-waste  

E-Print Network (OSTI)

Press Release Von Roll Inova to build the UK's largest energy-from-waste plant Zürich, September, 1 Roll Inova will build the UK's largest energy-from-waste facility. The contract is worth approximately and energy recovery. Apart from building and commissioning the plant, Von Roll Inova's scope of delivery also

Columbia University

38

Schwerpunkt Genetische Medizin und Genetische Epidemiologie -Bonn Die Identifizierung und Charakterisierung der genetischen Ursachen von Krankheiten sind  

E-Print Network (OSTI)

, Chemie, speziell organische Chemie 13.02. 1856 150. Geburtstag von Walter Voigt, Zoologie 14.02. 1881 125 26.02. 1931 75. Todestag von Otto Wallach, Chemie, speziell Systematisierung der Terpene Otto Wallach Günther Weydt, Neuere Deutsche Literatur 04.05. 1881 125. Todestag von Heinrich Josef Floss

Bartels, Soeren

39

ICME for Residual Stress  

Science Conference Proceedings (OSTI)

Oct 8, 2012 ... Application of ICME to Weld Process Innovations and Residual Stress ... Incorporation of Residual Stresses into Design of Ni-Base Superalloy ...

40

A New Value of the von Kármán Constant: Implications and Implementation  

Science Conference Proceedings (OSTI)

The von Kármán constant k occurs throughout the mathematics that describe the atmospheric boundary layer. In particular, because k was originally included in the definition of the Obukhov length, its value has both explicit and implicit effects ...

Edgar L. Andreas

2009-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Abelian subalgebras and the Jordan structure of a von Neumann algebra  

E-Print Network (OSTI)

For von Neumann algebras M, N not isomorphic to C^2 and without type I_2 summands, we show that for an order-isomorphism f:AbSub(M)->AbSub(N) between the posets of abelian von Neumann subalgebras of M and N, there is a unique Jordan *-isomorphism g:M->N with the image g[S] equal to f(S) for each abelian von Neumann subalgebra S of M. The converse also holds. This shows the Jordan structure of a von Neumann algebra not isomorphic to C^2 and without type I_2 summands is determined by the poset of its abelian subalgebras, and has implications in recent approaches to foundational issues in quantum mechanics.

Andreas Doering; John Harding

2010-09-24T23:59:59.000Z

42

Abelian subalgebras and the Jordan structure of a von Neumann algebra  

E-Print Network (OSTI)

For von Neumann algebras $\\mathcal{M},\\mathcal{N}$ without type $I_2$ summands, we show that for an order-isomorphism $f:AbSub \\mathcal{M}\\to AbSub \\mathcal{N}$ between the posets of abelian von Neumann subalgebras of $\\mathcal{M}$ and $\\mathcal{N}$, there is a unique Jordan *-isomorphism $g:\\mathcal{M}\\to \\mathcal{N}$ with the image $g[\\mathcal{S}]$ equal to $f(\\mathcal{S})$ for each abelian von Neumann-subalgebra $\\mathcal{S}$ of $\\mathcal{M}$. This shows the Jordan structure of a von Neumann algebra without type $I_2$ summand is determined by the poset of its abelian subalgebras, and has implications in recent approaches to foundational issues in quantum mechanics.

John Harding; Andreas Doering

2010-09-24T23:59:59.000Z

43

John von Neumann's Analysis of Gaussian Elimination and the Origins of Modern Numerical Analysis  

Science Conference Proceedings (OSTI)

Just when modern computers (digital, electronic, and programmable) were being invented, John von Neumann and Herman Goldstine wrote a paper to illustrate the mathematical analyses that they believed would be needed to use the new machines effectively ... Keywords: CFL condition, Gaussian elimination, backward error, computer architecture, computer arithmetic, computer programming, condition number, decomposition paradigm, history, matrix norms, numerical analysis, rounding error analysis, stability, stochastic linear algebra, von Neumann

Joseph F. Grcar

2011-11-01T23:59:59.000Z

44

Subventionierung von erneuerbarer Energie : eine industrieökonomische Analyse des strategischen Wettbewerbs in der Erneuerbaren-Energieindustrie bei unterschiedlichen staatlichen Regulierungen.  

E-Print Network (OSTI)

??In der vorliegenden Arbeit werden ausgewählte Probleme, die im Zusammenhang mit der Subventionierung von erneuerbarer Energien stehen, in finanztheoretischen und industrieökonomischen Modellen formal analysiert. Der… (more)

Schaller, Markus

2005-01-01T23:59:59.000Z

45

Stress pulse phenomena  

Science Conference Proceedings (OSTI)

This paper is an introductory discussion of stress pulse phenomena in simple solids and fluids. Stress pulse phenomena is a very rich and complex field that has been studied by many scientists and engineers. This paper describes the behavior of stress pulses in idealized materials. Inviscid fluids and simple solids are realistic enough to illustrate the basic behavior of stress pulses. Sections 2 through 8 deal with the behavior of pressure pulses. Pressure is best thought of as the average stress at a point. Section 9 deals with shear stresses which are most important in studying solids.

McGlaun, M.

1993-08-01T23:59:59.000Z

46

Techniques for Measuring Residual Stresses  

Science Conference Proceedings (OSTI)

Table 1   Classification of techniques for measuring residual stress...stress A-1 Stress-relaxation techniques using electric

47

Techniques for Measuring Residual Stresses  

Science Conference Proceedings (OSTI)

Table 1   Classification of techniques for measuring residual stress...stress A-1 Stress relaxation techniques using electric

48

Installation von Solid Edge ST4 Die Installationsdateien liegen als ZIP-Archiv vor und knnen im CAD-Pool auf den Rechnern des  

E-Print Network (OSTI)

Installation von Solid Edge ST4 Download Die Installationsdateien liegen als ZIP-Archiv vor und bleiben. Antivir von Avira meldet entfernen fälschlicherweise einige DLL's von Solid Edge als Trojaner starten. Installation Solid Edge ST4 Als erstes die *.zip-Datei entpacken (klick mit RMT auf die Datei

Berlin,Technische Universität

49

John von Neumann, 1956 | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

John von Neumann, 1956 John von Neumann, 1956 The Enrico Fermi Award Fermi Award Home Nomination & Selection Guidelines Award Laureates 2010's 2000's 1990's 1980's 1970's 1960's 1950's Ceremony The Life of Enrico Fermi Contact Information The Enrico Fermi Award U.S. Department of Energy SC-2/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-9395 E: fermi.award@science.doe.gov 1950's John von Neumann, 1956 Print Text Size: A A A RSS Feeds FeedbackShare Page Citation For his scientific contribution to the theory of fast computing machines and for his original contributions to their design and construction. More than anyone else he foresaw the important and necessary role they would play in the control and use of atomic energy and to the general advancement of the arts and sciences for the benefit of mankind

50

400 Jahre Chemie als Wissenschaft in Hamburg Von der Grndung des Akademischen Gymnasiums bis zu aktuellen  

E-Print Network (OSTI)

6 REIHE 1 400 Jahre Chemie als Wissenschaft in Hamburg Von der Gründung des Akademischen Gymnasiums bis zu aktuellen Forschungsthemen am Fachbereich Chemie der Universität Hamburg ZEIT UND ORT 08 als Wissenschaft in Hamburg zurückbli- cken. Der heutige Fachbereich Chemie der Universität Hamburg

Hamburg,.Universität

51

Im Zuge von Dissertationsrecherchen1 kam es zur Entdeckung eines bisher unbekann-  

E-Print Network (OSTI)

1925 durch die Grün- dung der gemeinsamen Einrichtungsfirma Haus & Garten eine Intensivierung. Der- ausstattung in Wien. Die Klientel von Haus & Garten entstammte dem wohlhabenden, überwiegend jüdischen. Die fast aus- schlie�lich mit Haus & Garten-Möbeln ein- gerichteten Interieurs wurden kürzlich im

Drmota, Michael

52

Focusing of weak shock waves and the von Neumann paradox of oblique shock reflection  

E-Print Network (OSTI)

Focusing of weak shock waves and the von Neumann paradox of oblique shock reflection Esteban G of weak shock waves at small angles are considered: the focusing of curved fronts at a&es, the transition between regular and irregular reflection of oblique shock waves on rigid walls and the diffraction

Tabak, Esteban G.

53

Diffraction: Stresses and Structures  

Science Conference Proceedings (OSTI)

Aug 6, 2013 ... O. Advanced Neutron and Synchrotron Studies of Materials: Diffraction: Stresses ... of Newcastle; 2ANSTO; 3European Spallation Source (ESS)

54

Stress Test | Open Energy Information  

Open Energy Info (EERE)

Stress Test Stress Test Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Stress Test Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Downhole Techniques Exploration Sub Group: Well Testing Techniques Parent Exploration Technique: Well Testing Techniques Information Provided by Technique Lithology: Stratigraphic/Structural: Fracture distribution and ambient tectonic stresses Hydrological: Fluid flow direction Thermal: Dictionary.png Stress Test: A geologic stress analysis based on images of a borehole wall and hydraulic fracturing tests to characterize fracture orientations and stress magnitudes in order to identify stress planes and zones of potential permeability. Other definitions:Wikipedia Reegle

55

BT8 Residual Stress Diffractometer  

Science Conference Proceedings (OSTI)

... Residual Stresses and Mechanical Damage in Gas Pipelines. ... Pressure in a pipeline superimposes a stress on ... are exceeded in pipelines with low ...

56

Radiation Stress Estimators  

Science Conference Proceedings (OSTI)

The radiation stresses Sij associated with the propagation of wind-generated waves are principal driving forces for several important surf-zone processes. The accurate estimation of the onshore flux of longshore-directed mean momentum Syx, using ...

S. S. Pawka; D. L. Inman; R. T. Guza

1983-09-01T23:59:59.000Z

57

Integration von dynamischer Verkehrssimulation und Wirkungsanalyse für die Entwicklung ressourcenschonender Verkehrsmanagement-Strategien  

E-Print Network (OSTI)

Um zu verhindern, dass die Nutzung von Telematik zu unerwünschten negativen Effekten führt, müssen Verkehrsmanagement-Strategien jenseits der blichen nutzeroptimalen Lsungen entwickelt werden. Mit diesem Ziel werden in dieser Arbeit dynamische Verkehrssimulationsmodelle und verfeinerte Prognose- und Auswertungsmodelle gekoppelt, mit denen Strategien hinsichtlich ihrer Umweltwirkungen und wirtschaftlichen Effizienz bewertet werden können. Hierfür stehen dynamische, mikroskopische Verkehrsmodelle zur Verfügung, die im Rahmen des "stadtinfoköln"-Projektes zu Prognoseinstrumenten weiter entwickelt werden. Als Ergebnis der Integration dieser Modelle mit Modellen zur strategischen Prognose und Bewertung von Verkehrswirkungen lassen sich erste Bandbreiten für die Wirksamkeit und Effizienz einzelner Verkehrsmanagement-Maßnahmen abschätzen. Gleichzeitig wird die Notwendigkeit zur Verfeinerung der Umweltmodelle deutlich, um den dynamischen Aspekten des Verkehrsablaufes Rechnung zu tragen. Daher werden Modelle zur Emissionsprognose im Straenverkehr weiterentwickelt und mit vorhandenen Simulationsmodellen (PELOPS) abgestimmt, welche die Fahrdynamik der Fahrzeuge berücksichtigen. Auf Basis der Ergebnisse werden erste Szenarien für Management-Strategien gezielt so entwickelt, dass vorgegebene Umwelt- und Sicherheitsziele erreicht und Wirtschaftlichkeitskriterien maximiert werden. Mittelfristig ist das Ziel, intelligente Entscheidungsunterstützungssysteme aufzubauen, die Verkehrsmanagern bei aus gemessenen Verkehrsdaten rekonstruierten realen Verkehrssituationen effiziente, ressourcensparende Lösungen von Verkehrsproblemen offerieren.

A. Gühnemann; N. Eissfeldt; A. Benmimoun; D. Neunzig; P. Wagner

2001-01-01T23:59:59.000Z

58

Piping stress handbook. Second edition  

Science Conference Proceedings (OSTI)

This abridged volume contains the following: Coefficients of thermal expansion. Allowable stress range for ANSI/ASME Power Piping Code B31.1. Stress intensification and flexibility factors. Pressure and stress ratios. Design criteria for allowable loads, moment, and stresses. Properties of pipe. Weight and dimensions of pipe and components. Pipe support selection and design. Fundamentals of expansion joints. Index.

Helguero, V.

1986-01-01T23:59:59.000Z

59

Stress inversion using slip tendency  

Science Conference Proceedings (OSTI)

The in situ stress state is an important controlling factor for the slip behavior of faults and fractures in the earth's crust and hence for the productivity of faulted and fractured hydrocarbon reservoirs. Current methods for stress tensor estimation ... Keywords: Slip tendency, Stress inversion, Stress tensor, Structural geology

John M. McFarland; Alan P. Morris; David A. Ferrill

2012-04-01T23:59:59.000Z

60

Evidence cross-validation and Bayesian inference of MAST plasma G. T. von Nessi, M. J. Hole, J. Svensson, and L. Appel  

E-Print Network (OSTI)

Evidence cross-validation and Bayesian inference of MAST plasma equilibria G. T. von Nessi, M. J cross-validation and Bayesian inference of MAST plasma equilibria G. T. von Nessi,1,a) M. J. Hole,1 J enable a good agree- ment between Bayesian inference of the last-closed flux-surface with other

Note: This page contains sample records for the topic "von mises stress" 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

Effect of magnetic boundary conditions on the dynamo threshold of von Karman swirling flows  

E-Print Network (OSTI)

We study the effect of different boundary conditions on the kinematic dynamo threshold of von Karman type swirling flows in a cylindrical geometry. Using an analytical test flow, we model different boundary conditions: insulating walls all over the flow, effect of sodium at rest on the cylinder side boundary, effect of sodium behind the impellers, effect of impellers or side wall made of a high-magnetic-permeability material. We find that using high-magnetic-permeability boundary conditions decreases the dynamo threshold, the minimum being achieved when they are implemented all over the flow.

Christophe Gissinger; Alexei Iskakov; Stephan Fauve; Emmanuel Dormy

2008-04-11T23:59:59.000Z

62

Residual Stresses and Numerical Simulation  

Science Conference Proceedings (OSTI)

Oct 28, 2013 ... Advances in Hydroelectric Turbine Manufacturing and Repair: Residual Stresses and Numerical Simulation Sponsored by: Metallurgical ...

63

Flat bundles, von Neumann algebras and $K$-theory with $\\R/\\Z$-coefficients.  

E-Print Network (OSTI)

Let $M$ be a closed manifold and $\\alpha : \\pi_1(M)\\to U_n$ a representation. We give a purely $K$-theoretic description of the associated element $[\\alpha]$ in the $K$-theory of $M$ with $\\R/\\Z$-coefficients. To that end, it is convenient to describe the $\\R/\\Z$-$K$-theory as a relative $K$-theory with respect to the inclusion of $\\C$ in a finite von Neumann algebra $B$. We use the following fact: there is, associated with $\\alpha$, a finite von Neumann algebra $B$ together with a flat bundle $\\cE\\to M$ with fibers $B$, such that $E_\\a\\otimes \\cE$ is canonically isomorphic with $\\C^n\\otimes \\cE$, where $E_\\alpha$ denotes the flat bundle with fiber $\\C^n$ associated with $\\alpha$. We also discuss the spectral flow and rho type description of the pairing of the class $[\\alpha]$ with the $K$-homology class of an elliptic selfadjoint (pseudo)-differential operator $D$ of order 1.

Paolo Antonini (IMJ); Sara Azzali (IMJ); Georges Skandalis (IMJ)

64

bersicht ber evaluierte Lehrveranstaltungen und Dozierende der Lehreinheit Chemie Seite 1 von 1 Anrede Vorname Name Anmel  

E-Print Network (OSTI)

�bersicht über evaluierte Lehrveranstaltungen und Dozierende der Lehreinheit Chemie Seite 1 von 1 Prof. Dr. Uwe Beginn nein Chemie Frau Brigitte HartmannAzanza nein Chemie Herr Dr. Dereje Hailu Taffa nein Chemie Herr Dr. Ulrich Wahlbrink nein Chemie Herr Prof. Dr. Lorenz Walder nein

Kallenrode, May-Britt

65

Faszination Chemie: Keine unter allen Wissenschaften bietet dem Menschen eine grssere Flle von Gegenstnden des Denkens, der berlegung und von frischer, sich stets erneuender Erkenntnis dar als die Chemie. F O T O : S C H U E R P F , Z R I C H  

E-Print Network (OSTI)

Faszination Chemie: «Keine unter allen Wissenschaften bietet dem Menschen eine grössere Fülle von Gegenständen des Denkens, der �berlegung und von frischer, sich stets erneuender Erkenntnis dar als die Chemie Gesellschaft Deutscher Chemi- ker beschrieben wurde, erregt nicht alle Forscher gleich. Oft stösst sie auf

Giger, Christine

66

High-Temperature Stress Relaxation Cracking and Stress Rupture ...  

Science Conference Proceedings (OSTI)

An incident occurred that resulted in the cracking of gasifier internals, bulging and stress rupture of the shell and the escape of hot syngas, causing a fire.

67

A luminescent nanocrystal stress gauge  

SciTech Connect

Microscale mechanical forces can determine important outcomes ranging from the site of material fracture to stem cell fate. However, local stresses in a vast majority of systems cannot be measured due to the limitations of current techniques. In this work, we present the design and implementation of the CdSe/CdS core/shell tetrapod nanocrystal, a local stress sensor with bright luminescence readout. We calibrate the tetrapod luminescence response to stress, and use the luminescence signal to report the spatial distribution of local stresses in single polyester fibers under uniaxial strain. The bright stress-dependent emission of the tetrapod, its nanoscale size, and its colloidal nature provide a unique tool that may be incorporated into a variety of micromechanical systems including materials and biological samples to quantify local stresses with high spatial resolution.

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

2010-10-25T23:59:59.000Z

68

Stress-Based Fatigue Monitoring  

Science Conference Proceedings (OSTI)

The FatiguePro software, developed by the Electric Power Research Institute (EPRI) and first deployed in 1989, is a fatigue monitoring program that is widely used around the world to assist with aging management of nuclear power plants. The FatiguePro stress-based fatigue (SBF) module has used a single stress term for calculating fatigue usage factors. This simplified approach was chosen not only because of computer limitations at the time, but also because the conventional stress cycle counting algorith...

2011-12-05T23:59:59.000Z

69

BT8 Residual Stress Diffractometer  

Science Conference Proceedings (OSTI)

... 5) T. Gnaupel-Herold, HJ Prask, AV Clark, CS Hehman, TN Nguyen, A Comparison of Neutron and Ultrasonic Determinations of Residual Stress ...

70

HTTF Core Stress Analysis  

SciTech Connect

In accordance with the need to determine whether cracking of the ceramic core disks which will be constructed and used in the High Temperature Test Facility (HTTF) for heatup and cooldown experiments, a set of calculation were performed using Abaqus to investigate the thermal stresses levels and likelihood for cracking. The calculations showed that using the material properties provided for the Greencast 94F ceramic, cracking is predicted to occur. However, this modeling does not predict the size or length of the actual cracks. It is quite likely that cracks will be narrow with rough walls which would impede the flow of coolant gases entering the cracks. Based on data recorded at Oregon State University using Greencast 94F samples that were heated and cooled at prescribed rates, it was concluded that the likelihood that the cracks would be detrimental to the experimental objectives is small.

Brian D. Hawkes; Richard Schultz

2012-07-01T23:59:59.000Z

71

Residual stresses and stress corrosion cracking in pipe fittings  

Science Conference Proceedings (OSTI)

Residual stresses can play a key role in the SCC performance of susceptible materials in PWR primary water applications. Residual stresses are stresses stored within the metal that develop during deformation and persist in the absence of external forces or temperature gradients. Sources of residual stresses in pipe fittings include fabrication processes, installation and welding. There are a number of methods to characterize the magnitude and orientation of residual stresses. These include numerical analysis, chemical cracking tests, and measurement (e.g., X-ray diffraction, neutron diffraction, strain gage/hole drilling, strain gage/trepanning, strain gage/section and layer removal, and acoustics). This paper presents 400 C steam SCC test results demonstrating that residual stresses in as-fabricated Alloy 600 pipe fittings are sufficient to induce SCC. Residual stresses present in as-fabricated pipe fittings are characterized by chemical cracking tests (stainless steel fittings tested in boiling magnesium chloride solution) and by the sectioning and layer removal (SLR) technique.

Parrington, R.J.; Scott, J.J.; Torres, F.

1994-06-01T23:59:59.000Z

72

RESIDUAL STRESSES IN 3013 CONTAINERS  

SciTech Connect

The DOE Complex is packaging plutonium-bearing materials for storage and eventual disposition or disposal. The materials are handled according to the DOE-STD-3013 which outlines general requirements for stabilization, packaging and long-term storage. The storage vessels for the plutonium-bearing materials are termed 3013 containers. Stress corrosion cracking has been identified as a potential container degradation mode and this work determined that the residual stresses in the containers are sufficient to support such cracking. Sections of the 3013 outer, inner, and convenience containers, in both the as-fabricated condition and the closure welded condition, were evaluated per ASTM standard G-36. The standard requires exposure to a boiling magnesium chloride solution, which is an aggressive testing solution. Tests in a less aggressive 40% calcium chloride solution were also conducted. These tests were used to reveal the relative stress corrosion cracking susceptibility of the as fabricated 3013 containers. Significant cracking was observed in all containers in areas near welds and transitions in the container diameter. Stress corrosion cracks developed in both the lid and the body of gas tungsten arc welded and laser closure welded containers. The development of stress corrosion cracks in the as-fabricated and in the closure welded container samples demonstrates that the residual stresses in the 3013 containers are sufficient to support stress corrosion cracking if the environmental conditions inside the containers do not preclude the cracking process.

Mickalonis, J.; Dunn, K.

2009-11-10T23:59:59.000Z

73

Mapping Tectonic Stress Using Earthquakes  

SciTech Connect

An earthquakes occurs when the forces acting on a fault overcome its intrinsic strength and cause it to slip abruptly. Understanding more specifically why earthquakes occur at particular locations and times is complicated because in many cases we do not know what these forces actually are, or indeed what processes ultimately trigger slip. The goal of this study is to develop, test, and implement a Bayesian method of reliably determining tectonic stresses using the most abundant stress gauges available - earthquakes themselves.Existing algorithms produce reasonable estimates of the principal stress directions, but yield unreliable error bounds as a consequence of the generally weak constraint on stress imposed by any single earthquake, observational errors, and an unavoidable ambiguity between the fault normal and the slip vector.A statistical treatment of the problem can take into account observational errors, combine data from multiple earthquakes in a consistent manner, and provide realistic error bounds on the estimated principal stress directions.We have developed a realistic physical framework for modelling multiple earthquakes and show how the strong physical and geometrical constraints present in this problem allow inference to be made about the orientation of the principal axes of stress in the earth's crust.

Arnold, Richard; Townend, John; Vignaux, Tony [Victoria University of Wellington, PO Box 600, Wellington (New Zealand)

2005-11-23T23:59:59.000Z

74

Speech Under Stress: Analysis, Modeling and Recognition  

Science Conference Proceedings (OSTI)

In this chapter, we consider a range of issues associated with analysis, modeling, and recognition of speech under stress. We start by defining stress, what could be perceived as stress, and how it affects the speech production system. In the discussion ... Keywords: Lombard effect, Teager energy operator, hidden Markov models, pitch contours, robustness in speech recognition, speech technology, stress classification

John H. Hansen; Sanjay Patil

2007-02-01T23:59:59.000Z

75

Growth-optimal investments and numeraire portfolios under transaction costs: An analysis based on the von Neumann-Gale model  

E-Print Network (OSTI)

The aim of this work is to extend the capital growth theory developed by Kelly, Breiman, Cover and others to asset market models with transaction costs. We define a natural generalization of the notion of a numeraire portfolio proposed by Long and show how such portfolios can be used for constructing growth-optimal investment strategies. The analysis is based on the classical von Neumann-Gale model of economic dynamics, a stochastic version of which we use as a framework for the modelling of financial markets with frictions.

Bahsoun, Wael; Taksar, Michael I

2009-01-01T23:59:59.000Z

76

Very Slow Strain Rate Stress-Strain Behavior and Resisting Stress ...  

Science Conference Proceedings (OSTI)

rectly obtained from measurements of yield stress and flow stress made in constant strain rate tests at creep strain rates and temperatures. In this paper, constant.

77

STResS (Simulated Toxicant-Related Stress) documentation  

Science Conference Proceedings (OSTI)

STResS (Simulated Toxicant-Related Stress) is a program written in DEC FORTRAN v. 6.2. This program can be run either interactively or batch mode. This program is designed to model the effects of toxicant exposure on a simulated population of a specific species, as well as the effects of the toxicant on the demographic and genetic characteristics. The toxic effect on the time-to-death is based on an accelerated failure time model in which the time-to-death depends on size, sex and genotype, toxicant concentration, and frequency and duration of exposure. Sexual, fecundity, and meiotic drive/gametic selection can also be included. Multiple simulations can be run for a user-specified number of gestation periods of user-specified length. The effect of winter can be included, and the exposure duration can be changed once during each simulation, if desired.

Greene, K.D.; Newman, M.C.; Jagoe, R.H.

1994-12-31T23:59:59.000Z

78

Dark, Hypoxia, Herbicide, Other Stresses Energy Deprivation  

E-Print Network (OSTI)

Dark, Hypoxia, Herbicide, Other Stresses Energy Deprivation Upstream PKs GBF5, bZIP11, 53, 1 Glycolysis NR, SPS, HMG-CoAR Energy homeostasis, Growth, Stress response, Survival Development, Reproduction. Plants are constantly challenged by multiple types of stress that ultimately converge as an energy

Sheen, Jen

79

UniReport Satzungen und Ordnungen vom 06.01.2009 Satzung der Johann Wolfgang Goethe-Universitt Frankfurt am Main fr die Auswahl von aus-  

E-Print Network (OSTI)

Hochschulzugangsberechtigung und zu 49 % aus dem Durchschnitt der Noten in Mathematik, Biologie, Chemie und Physik und Deutsch über die Deutsche Sprachprüfung für den Hochschulzugang (DSH) - ggf. das Ergebnis des fachspezifischen Anerkennung von Studienleistungen nebst An- lagen - ggf. der Nachweis über die Deutsche Sprachprüfung für den

Mester, Rudolf

80

Elastoplastic implicit integration algorithm applicable to both plane stress and three-dimensional stress states  

Science Conference Proceedings (OSTI)

An elastoplastic implicit integration algorithm applicable to both plane stress and three-dimensional stress states is developed for a general class of combined nonlinear kinematic-isotropic hardening models. The algorithm is first built for three-dimensional ... Keywords: Constitutive models, Implicit integration, Plane stress, Plasticity, Three-dimensional stress

Nobutada Ohno; Masatoshi Tsuda; Takafumi Kamei

2013-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Directional Stress Indices and Stress Intensification Factors for 90 Degree Elbows (PWRMRP-06)  

Science Conference Proceedings (OSTI)

This report provides equations, based on analyses and test data, for determining the directional stress indices and stress intensification factors (SIFs) for 90 degree elbows. Present methodologies used to determine these parameters are generally overly conservative. The report contains results of an investigation into the stress intensification factors and directional stress indices of 90 degree elbows.

1999-12-22T23:59:59.000Z

82

Estimating stress heterogeneity from aftershock rate  

E-Print Network (OSTI)

We estimate the rate of aftershocks triggered by a heterogeneous stress change, using the rate-and-state model of Dieterich [1994]. We show than an exponential stress distribution P(\\tau)~ exp(-\\tau/\\tau_0) gives an Omori law decay of aftershocks with time ~1/t^p, with an exponent p=1-A\\sigma_n/\\tau_0, where A is a parameter of the rate-and-state friction law, and \\sigma_n the normal stress. Omori exponent p thus decreases if the stress "heterogeneity" \\tau_0 decreases. We also invert the stress distribution P(\\tau) from the seismicity rate R(t), assuming that the stress does not change with time. We apply this method to a synthetic stress map, using the (modified) scale invariant "k^2" slip model [Herrero and Bernard, 1994]. We generate synthetic aftershock catalogs from this stress change. The seismicity rate on the rupture area shows a huge increase at short times, even if the stress decreases on average. This stochastic slip model gives a Gaussian stress distribution, but nevertheless produces an aftersho...

Helmstetter, A; Helmstetter, Agnes; Shaw, Bruce E.

2005-01-01T23:59:59.000Z

83

SANDIA REPORT SAND98-0260 UC-705 Unlimited Release  

Office of Scientific and Technical Information (OSTI)

8-0260 UC-705 8-0260 UC-705 Unlimited Release Printed February 1998 An Efficient Method for Calculating RMS von Mises Stress in a Random Vibration Environment Daniel J. Segalman, Clay W. G. Fulcher, Garth M. Reese, R Prepared by Sandia National Labora Sc2900Q18-81) Issued by Sanma National Laboratories, operated for the United States Department of Energy by Sandia Corporation. NOTICE: This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Govern- ment nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, o r assumes any legal liability or responsibility for the accuracy, completeness, o

84

Thermoplastic deformation of silicon surfaces induced by ultrashort pulsed lasers in submelting conditions  

Science Conference Proceedings (OSTI)

A hybrid theoretical model is presented to describe thermoplastic deformation effects on silicon surfaces induced by single and multiple ultrashort pulsed laser irradiation in submelting conditions. An approximation of the Boltzmann transport equation is adopted to describe the laser irradiation process. The evolution of the induced deformation field is described initially by adopting the differential equations of dynamic thermoelasticity while the onset of plastic yielding is described by the von Mises stress. Details of the resulting picometre sized crater, produced by irradiation with a single pulse, are discussed as a function of the imposed conditions and thresholds for the onset of plasticity are computed. Irradiation with multiple pulses leads to ripple formation of nanometre size that originates from the interference of the incident and a surface scattered wave. It is suggested that ultrafast laser induced surface modification in semiconductors is feasible in submelting conditions, and it may act as a precursor of the incubation effects observed at multiple pulse irradiation of materials surfaces.

Tsibidis, G. D. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology (FORTH), N. Plastira 100, Vassilika Vouton, 70013, Heraklion, Crete (Greece); Stratakis, E. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology (FORTH), N. Plastira 100, Vassilika Vouton, 70013, Heraklion, Crete (Greece); Department of Materials Science and Technology, University of Crete, 710 03 Heraklion, Crete (Greece); Aifantis, K. E. [Laboratory of Mechanics and Materials, Aristotle University of Thessaloniki, GR-54006 Thessaloniki (Greece)

2012-03-01T23:59:59.000Z

85

A Benchmark Study on Casting Residual Stress  

Science Conference Proceedings (OSTI)

Stringent regulatory requirements, such as Tier IV norms, have pushed the cast iron for automotive applications to its limit. The castings need to be designed with closer tolerances by incorporating hitherto unknowns, such as residual stresses arising due to thermal gradients, phase and microstructural changes during solidification phenomenon. Residual stresses were earlier neglected in the casting designs by incorporating large factors of safety. Experimental measurement of residual stress in a casting through neutron or X-ray diffraction, sectioning or hole drilling, magnetic, electric or photoelastic measurements is very difficult and time consuming exercise. A detailed multi-physics model, incorporating thermo-mechanical and phase transformation phenomenon, provides an attractive alternative to assess the residual stresses generated during casting. However, before relying on the simulation methodology, it is important to rigorously validate the prediction capability by comparing it to experimental measurements. In the present work, a benchmark study was undertaken for casting residual stress measurements through neutron diffraction, which was subsequently used to validate the accuracy of simulation prediction. The stress lattice specimen geometry was designed such that subsequent castings would generate adequate residual stresses during solidification and cooling, without any cracks. The residual stresses in the cast specimen were measured using neutron diffraction. Considering the difficulty in accessing the neutron diffraction facility, these measurements can be considered as benchmark for casting simulation validations. Simulations were performed using the identical specimen geometry and casting conditions for predictions of residual stresses. The simulation predictions were found to agree well with the experimentally measured residual stresses. The experimentally validated model can be subsequently used to predict residual stresses in different cast components. This enables incorporation of the residual stresses at the design phase along with external loads for accurate predictions of fatigue and fracture performance of the cast components.

Johnson, Eric M. [John Deere -- Moline Tech Center; Watkins, Thomas R [ORNL; Schmidlin, Joshua E [ORNL; Dutler, S. A. [MAGMA Foundry Technologies, Inc.

2012-01-01T23:59:59.000Z

86

Analysis and Modeling of Stresses in Thermoelectrics  

Science Conference Proceedings (OSTI)

Oct 28, 2013 ... Our stress distribution results indicate that the brittle TE alloys of the ... source of energy by converting a temperature gradient to electricity.

87

Sulfide Stress Cracking in Steels - A Review  

Science Conference Proceedings (OSTI)

Symposium, Corrosion and Corrosion Protection of Materials in the Oil and Gas Industry. Presentation Title, Sulfide Stress Cracking in Steels - A Review.

88

Residual stresses in IN 718 Turbine Disks  

Science Conference Proceedings (OSTI)

the thermally induced residual stresses in plate-like components during cooling. The plate is. 527 ... cooled down symmetrically with respect to its middle plane.

89

Stress Corrosion Cracking - Programmaster.org  

Science Conference Proceedings (OSTI)

Oct 28, 2013 ... Atomic Ordering in Alloy 690 and Its Effect on Long-term Structural Stability and Stress Corrosion Cracking Susceptibility: Michael Kaufman1; ...

90

Cat under Food and Water Stress  

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

Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Cat under Food and Water Stress Name: Nitin Status: other Grade: other Location: Outside...

91

Evaluation of Stress-Corrosion Cracking  

Science Conference Proceedings (OSTI)

Table 3   Stress-corrosion cracking of selected material systems...chlorides, seawater Oil/gas production and transmission, oil refining,

92

On the Climatic Impact of Wind Stress  

Science Conference Proceedings (OSTI)

A climate model is used to study the climatic impact of the stress exerted on the ocean by the atmosphere. When this stress is set to zero everywhere, the climate becomes much colder, with global-mean near-surface air temperature dropping from ...

Oleg A. Saenko

2009-01-01T23:59:59.000Z

93

Wind-Stress Coefficients at Light Winds  

Science Conference Proceedings (OSTI)

The increase of the wind-stress coefficient with wind velocity was found to start with winds as light as 3 m s?1, below which, following the formula for aerodynamically smooth flows, the wind-stress coefficient decreases as the wind velocity ...

Jin Wu

1988-12-01T23:59:59.000Z

94

STRESS CORROSION CRACKING IN TEAR DROP SPECIMENS  

SciTech Connect

Laboratory tests were conducted to investigate the stress corrosion cracking (SCC) of 304L stainless steel used to construct the containment vessels for the storage of plutonium-bearing materials. The tear drop corrosion specimens each with an autogenous weld in the center were placed in contact with moist plutonium oxide and chloride salt mixtures. Cracking was found in two of the specimens in the heat affected zone (HAZ) at the apex area. Finite element analysis was performed to simulate the specimen fabrication for determining the internal stress which caused SCC to occur. It was found that the tensile stress at the crack initiation site was about 30% lower than the highest stress which had been shifted to the shoulders of the specimen due to the specimen fabrication process. This finding appears to indicate that the SCC initiation took place in favor of the possibly weaker weld/base metal interface at a sufficiently high level of background stress. The base material, even subject to a higher tensile stress, was not cracked. The relieving of tensile stress due to SCC initiation and growth in the HAZ and the weld might have foreclosed the potential for cracking at the specimen shoulders where higher stress was found.

Lam, P; Philip Zapp, P; Jonathan Duffey, J; Kerry Dunn, K

2009-05-01T23:59:59.000Z

95

A critical review of residual stress technology  

Science Conference Proceedings (OSTI)

The current technology for evaluating residual in materials has been critically reviewed from the perspective of LLNL needs. The primary technique available continues to be x-ray diffraction (XRD). Substantial analytical and experimental refinements have been made in the past decade. An especially promising development in XRD is the use of energy dispersive spectroscopy for evaluating triaxial stress. This would provide an alternative to neutron diffraction, a technique limited to a relatively small number of outside laboratories. Recent research in residual stress measurement using ultrasonics have concentrated on shear wave techniques. Substantial progress has been made in the use of electromagnetic acoustic transducers (EMAT's), surface waves, corrections for texture, and, of special interest to LLNL, the ability to characterize interfacial stress. Strain gages and related technologies continue to be actively used in field measurements of residual stress, although there is generally some destructive nature to those techniques. An increased use of multiple technique approaches to residual stress evaluation is occurring for the purposes of both verification and complementary measurements. Among a number of miscellaneous techniques found in the recent literature are several involving the use of stress-sensitive magnetic properties and an especially promising use of the thermoelastic effect for noncontact stress mapping. Recommendations for LLNL activity include energy dispersive XRD, ultrasonics characterization of anisotropy and interfacial stress, and investigation of the thermoelastic effect. 57 refs.

Shackelford, J.F.; Brown, B.D.

1987-09-30T23:59:59.000Z

96

Over Core Stress | Open Energy Information  

Open Energy Info (EERE)

Over Core Stress Over Core Stress Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Over Core Stress Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Over Core Stress: No definition has been provided for this term. Add a Definition Related Techniques Rock Lab Analysis Core Analysis Cuttings Analysis Isotopic Analysis- Rock Over Core Stress Paleomagnetic Measurements Petrography Analysis Rock Density X-Ray Diffraction (XRD) X-Ray Fluorescence (XRF) References Page Area Activity Start Date Activity End Date Reference Material

97

Wellbore stress distribution produced by moisture adsorption  

SciTech Connect

For this study, the authors evaluated the stress distribution produced by moisture adsorption around a wellbore by applying the mechanics of deformable solids. This paper shows that the moisture-adsorption process is governed by a diffusion equation and that the equations governing the moisture-induced stress around the hole are similar to those equations used in thermoelasticity. A computational method is developed for calculating the stress distribution around the borehole, and the experimental procedure for obtaining the material constants needed in the computation is presented. This paper also studies the effect of borehole pressure on the stress distribution around the hole. Results show that the magnitude and distribution of stresses around the borehole are very sensitive to the adsorption characteristics and the moisture-induced modulus change of the material.

Yew, C.H.; Chenevert, M.E.; Wang, C.L.; Osisanya, S.O. (Univ. of Texas, TX (US))

1990-12-01T23:59:59.000Z

98

Onset Mechanism of Strain-Rate-Induced Flow Stress Upturn  

E-Print Network (OSTI)

The strain-rate response of flow stress in a plastically deforming crystal is formulated through a stress-sensitive dislocation mobility model that can be evaluated by atomistic simulation. For the flow stress of a model ...

Fan, Yue

99

The Neutron Residual Stress Mapping Facility at HFIR | ORNL Neutron...  

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

Neutron Residual Stress Mapping Facility at HFIR Neutron Residual Stress Mapping Facility (HB-2B) Neutron Residual Stress Mapping Facility (HB-2B). The HB-2B beam port is optimized...

100

COMPRESSIVE STRESS SYSTEM FOR A GAS TURBINE ENGINE - Energy ...  

The present application provides a compressive stress system for a gas turbine engine. The compressive stress system may include a first bucket ...

Note: This page contains sample records for the topic "von mises stress" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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to obtain the most current and comprehensive results.


101

Model for the Superimposed Effects of Stress-Corrosion Cracking ...  

Science Conference Proceedings (OSTI)

Symposium, Fatigue and Corrosion Damage in Metallic Materials: Fundamentals, ... and a stress-corrosion cracking mode acting at high stress intensity in NaCl.

102

Residual stress determination using strain gage measurements  

Science Conference Proceedings (OSTI)

A strain gage technique, which relates the prior residual stress state in a material to the strain data obtained by fixing a strain gage on one surface and grinding off the other, has been proposed previously. In the current work, a generalized solution for obtaining an arbitrary residual stress profile from strain gage data is presented. Numerical analysis using the solution indicates that the formulation is insensitive to random errors of 10% or less in the experimental data. Based on the results of the analysis, a procedure for determining stress profiles from strain gage data is outlined. Experimental data for tempered glass was analyzed using the technique proposed. The stress profiles predicted are in good agreement with independent observations using indentation and strength data.

Tandon, R.; Green, D.J. (Dept. of Materials Science and Engineering, Pennsylvania State Univ., University Park, PA (US))

1990-09-01T23:59:59.000Z

103

Determination of Longitudinal Stress in Rails  

E-Print Network (OSTI)

The objective of this research is to determine the longitudinal stress in rails by using the polarization of Rayleigh waves. Analytical models are developed to describe the effect of applied stress on wave speed and on the polarization of Rayleigh waves. A numerical simulation is performed to find the effect of applied stress on wave velocity and Rayleigh wave polarization. The effect of uncertainties in material properties on wave velocity and polarization of Rayleigh wave is also examined in the simulation. The experiment uses a laser Doppler vibrometer (LDV) to measure the particle velocities. The in-plane and out-of-plane velocity components are obtained from the measured particle velocities. The polarization of Rayleigh wave, which is defined as the ratio between the in-plane and out-of-plane displacements, is calculated. Furthermore, the polarization of the Rayleigh wave is considered as a measure to identify applied stress. The experiment is performed on unstressed and stressed rail specimen. Thus, Rayleigh wave polarization is obtained as a function of applied stress. The experimental results are compared with the analytical model. The result shows a good agreement with the theoretical values for unstressed rail.

Djayaputra, Ferdinand

2010-12-01T23:59:59.000Z

104

Dynamic response of Cu4Zr54 metallic glass to high strain rate shock loading: plasticity, spall and atomic-level structures  

SciTech Connect

We investigate dynamic response of Cu{sub 46}Zr{sub 54} metallic glass under adiabatic planar shock wave loading (one-dimensional strain) wjth molecular dynamics simulations, including Hugoniot (shock) states, shock-induced plasticity and spallation. The Hugoniot states are obtained up to 60 CPa along with the von Mises shear flow strengths, and the dynamic spall strength, at different strain rates and temperatures. The spall strengths likely represent the limiting values achievable in experiments such as laser ablation. For the steady shock states, a clear elastic-plastic transition is identified (e.g., in the shock velocity-particle velocity curve), and the shear strength shows strain-softening. However, the elastic-plastic transition across the shock front displays transient stress overshoot (hardening) above the Hugoniot elastic limit followed by a relatively sluggish relaxation to the steady shock state, and the plastic shock front steepens with increasing shock strength. The local von Mises shear strain analysis is used to characterize local deformation, and the Voronoi tessellation analysis, the corresponding short-range structures at various stages of shock, release, tension and spallation. The plasticity in this glass is manifested as localized shear transformation zones and of local structure rather than thermal origin, and void nucleation occurs preferentially at the highly shear-deformed regions. The Voronoi and shear strain analyses show that the atoms with different local structures are of different shear resistances that lead to shear localization (e.g., the atoms indexed with (0,0,12,0) are most shear-resistant, and those with (0,2,8,1) are highly prone to shear flow). The dynamic changes in local structures are consistent with the observed deformation dynamics.

Luo, Shengnian [Los Alamos National Laboratory; Arman, Bedri [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory; Cagin, Tahir [TEXAS A& M UNIV

2009-01-01T23:59:59.000Z

105

Spatially discriminating Russian wheat aphid induced plant stress from other wheat stressing factors  

Science Conference Proceedings (OSTI)

The Russian wheat aphid (RWA) Diuraphis noxia (Mordvilko) is a major pest of winter wheat and barley in the United States. RWA induces stress to the wheat crop by damaging plant foliage, lowering the greenness of plants, and affecting productivity. The ... Keywords: Discriminant function analysis, Plant stress, Russian wheat aphid, Spatial pattern metrics

Georges F. Backoulou; Norman C. Elliott; Kristopher Giles; Mpho Phoofolo; Vasile Catana; Mustafa Mirik; Jerry Michels

2011-09-01T23:59:59.000Z

106

Modified Shortwave Infrared Perpendicular Water Stress Index: A Farmland Water Stress Monitoring Method  

Science Conference Proceedings (OSTI)

Crop water stress monitoring by remote sensing has been the focus of numerous studies. In this paper, specifically red (630-690 nm) and shortwave infrared SWIR (1550-1750 nm), are identified to monitor farmland water stress, and a method (Modified ...

Feng Haixia; Chen Chao; Dong Heng; Wang Jinliang; Meng Qingye

107

Response of Desulfovibrio vulgaris to Alkaline Stress  

SciTech Connect

The response of exponentially growing Desulfovibrio vulgarisHildenborough to pH 10 stress was studied using oligonucleotidemicroarrays and a study set of mutants with genes suggested by microarraydata to be involved in the alkaline stress response deleted. The datashowed that the response of D. vulgaris to increased pH is generallysimilar to that of Escherichia coli but is apparently controlled byunique regulatory circuits since the alternative sigma factors (sigma Sand sigma E) contributing to this stress response in E. coli appear to beabsent in D. vulgaris. Genes previously reported to be up-regulated in E.coli were up-regulated in D. vulgaris; these genes included three ATPasegenes and a tryptophan synthase gene. Transcription of chaperone andprotease genes (encoding ATP-dependent Clp and La proteases and DnaK) wasalso elevated in D. vulgaris. As in E. coli, genes involved in flagellumsynthesis were down-regulated. The transcriptional data also identifiedregulators, distinct from sigma S and sigma E, that are likely part of aD. vulgaris Hildenborough-specific stress response system.Characterization of a study set of mutants with genes implicated inalkaline stress response deleted confirmed that there was protectiveinvolvement of the sodium/proton antiporter NhaC-2, tryptophanase A, andtwo putative regulators/histidine kinases (DVU0331 andDVU2580).

Stolyar, S.; He, Q.; He, Z.; Yang, Z.; Borglin, S.E.; Joyner, D.; Huang, K.; Alm, E.; Hazen, T.C.; Zhou, J.; Wall, J.D.; Arkin, A.P.; Stahl, D.A.

2007-11-30T23:59:59.000Z

108

System and method for measuring residual stress  

DOE Patents (OSTI)

The present invention is a method and system for determining the residual stress within an elastic object. In the method, an elastic object is cut along a path having a known configuration. The cut creates a portion of the object having a new free surface. The free surface then deforms to a contour which is different from the path. Next, the contour is measured to determine how much deformation has occurred across the new free surface. Points defining the contour are collected in an empirical data set. The portion of the object is then modeled in a computer simulator. The points in the empirical data set are entered into the computer simulator. The computer simulator then calculates the residual stress along the path which caused the points within the object to move to the positions measured in the empirical data set. The calculated residual stress is then presented in a useful format to an analyst.

Prime, Michael B. (Los Alamos, NM)

2002-01-01T23:59:59.000Z

109

Visualization of salt-induced stress perturbations.  

Science Conference Proceedings (OSTI)

An important challenge encountered during post-processing of finite element analyses is the visualizing of three-dimensional fields of real-valued second-order tensors. Namely, as finite element meshes become more complex and detailed, evaluation and presentation of the principal stresses becomes correspondingly problematic. In this paper, we describe techniques used to visualize simulations of perturbed in-situ stress fields associated with hypothetical salt bodies in the Gulf of Mexico. We present an adaptation of the Mohr diagram, a graphical paper and pencil method used by the material mechanics community for estimating coordinate transformations for stress tensors, as a new tensor glyph for dynamically exploring tensor variables within three-dimensional finite element models. This interactive glyph can be used as either a probe or a filter through brushing and linking.

Crossno, Patricia Joyce; Brannon, Rebecca Moss; Coblentz, David D.; Rogers, David H.

2004-10-01T23:59:59.000Z

110

Application of stress corrosion to geothermal reservoirs  

DOE Green Energy (OSTI)

There are several alternative equations which describe slow crack growth by stress corrosion. Presently available data suggest that an alternative form may be preferable to the form which is most often used, but the issue cannot be clearly decided. Presently available stress corrosion data on glasses and ceramics suggest that rocks in a proposed geothermal reservoir will crack readily over long time periods, thus seriously limiting the operation of this type of power source. However, in situ hydrofracturing measurements together with a theoretical treatment suggest that such a reservoir will contain a relatively high pressure over a long period of time without further cracking. Further experimentation is desirable to measure directly the critical stresses for crack growth rates on the order of 10/sup -7/ m/sec.

Demarest, H.H. Jr.

1975-10-01T23:59:59.000Z

111

A High shear stress segment along the San Andreas Fault: Inferences based on near-field stress direction and stress magnitude observations in the Carrizo Plain Area  

SciTech Connect

Nearly 200 new in-situ determinations of stress directions and stress magnitudes near the Carrizo plain segment of the San Andreas fault indicate a marked change in stress state occurring within 20 km of this principal transform plate boundary. A natural consequence of this stress transition is that if the observed near-field ``fault-oblique`` stress directions are representative of the fault stress state, the Mohr-Coulomb shear stresses resolved on San Andreas sub-parallel planes are substantially greater than previously inferred based on fault-normal compression. Although the directional stress data and near-hydrostatic pore pressures, which exist within 15 km of the fault, support a high shear stress environment near the fault, appealing to elevated pore pressures in the fault zone (Byerlee-Rice Model) merely enhances the likelihood of shear failure. These near-field stress observations raise important questions regarding what previous stress observations have actually been measuring. The ``fault-normal`` stress direction measured out to 70 km from the fault can be interpreted as representing a comparable depth average shear strength of the principal plate boundary. Stress measurements closer to the fault reflect a shallower depth-average representation of the fault zone shear strength. If this is true, only stress observations at fault distances comparable to the seismogenic depth will be representative of the fault zone shear strength. This is consistent with results from dislocation monitoring where there is pronounced shear stress accumulation out to 20 km of the fault as a result of aseismic slip within the lower crust loading the upper locked section. Beyond about 20 km, the shear stress resolved on San Andreas fault-parallel planes becomes negligible. 65 refs., 15 figs.

Castillo, D. A., [Department of Geology and Geophysics, University of Adelaide (Australia); Younker, L.W. [Lawrence Livermore National Lab., CA (United States)

1997-01-30T23:59:59.000Z

112

Grading of lumber using stress waves  

E-Print Network (OSTI)

The goal of this research was to develop stress wave grading technology suitable for small lumber mills. Specific goals include: 1) develop an ultrasonic probe configuration to facilitate real-time grain angle and edge knot measurement, 2) determine the statistical correlation between localized stress wave indices and lumber tensile strength and 3) compare the ultrasonic technique with other nondestructive evaluation (NDE) measurements including static MOE, impact stress wave and transverse vibration. Two hundred pieces of 2 x 6 Southern Pine lumber were randomly sampled. Material properties and NDE measurements such as static MOE, impact stress wave and transverse vibration MOEs were collected for the lumber. Before proceeding with final ultrasonic testing, pilot studies were done to study the effect of the strength reducing factors, such as grain angle and edge knots, on ultrasonic wave velocity. Wave velocity decreased as grain angle increased, with more apparent loss taking place at lower angles. The presence of edge knots decreased the wave velocity as measured along the narrow edge of the lumber. Using the knowledge gained from the pilot studies an ultrasonic probe configuration was devised to detect gross grain angle and edge knots. The tests were carried on the lumber using the configuration. Statistical models from localized stress wave indices were developed to predict the tensile strength. The linear correlation between predicted and actual ultimate tensile strength was 0.724. Ultrasonic testing was a slightly better predictor of ultimate tensile strength than shortspan bending, impact stress wave and transverse vibration techniques which had linear correlations of 0.716, 0.696 and 0.716 respectively. Separately including impact stress wave and transverse vibration MOEs into the ultrasonic model resulted in improved linear correlations of 0.769 and 0.787, respectively. In summary, knowledge from this study will be useful in the continuing development of stress wave lumber grading technology. Even though the results were only slightly better than those with short span bending and transverse vibration techniques, the ultrasonic technique appears to be promising for grading of wood.

Bethi, Rajeshwar

1994-01-01T23:59:59.000Z

113

Stress- and Chemistry-Mediated Permeability Enhancement/Degradation in Stimulated Critically-Stressed Fractures  

DOE Green Energy (OSTI)

This work has investigated the interactions between stress and chemistry in controlling the evolution of permeability in stimulated fractured reservoirs through an integrated program of experimentation and modeling. Flow-through experiments on natural and artificial fractures in Coso diorite have examined the evolution of permeability under paths of mean and deviatoric stresses, including the role of dissolution and precipitation. Models accommodating these behaviors have examined the importance of incorporating the complex couplings between stress and chemistry in examining the evolution of permeability in EGS reservoirs. This document reports the findings of experiment [1,2] and analysis [3,4], in four sequential chapters.

Derek Elsworth; Abraham S. Grader; Chris Marone; Phillip Halleck; Peter Rose; Igor Faoro; Joshua Taron; André Niemeijer; Hideaki Yasuhara

2009-03-30T23:59:59.000Z

114

The gravitoelectromagnetic stress-energy tensor  

E-Print Network (OSTI)

We study the pseudo-local gravitoelectromagnetic stress-energy tensor for an arbitrary gravitational field within the framework of general relativity. It is shown that there exists a current of gravitational energy around a rotating mass. This gravitational analog of the Poynting flux is evaluated for certain classes of observers in the Kerr field.

B. Mashhoon; J. C. McClune; H. Quevedo

1998-05-27T23:59:59.000Z

115

Wind Stress Measurements from the Open Ocean  

Science Conference Proceedings (OSTI)

An automatic inertial dissipation system was used during three cruises of the RRS Discovery in the Southern Ocean to obtain a large dataset of open ocean wind stress estimates. The wind speed varied from near calm to 26 m s?1, and the sea-air ...

Margaret Yelland; Peter K. Taylor

1996-04-01T23:59:59.000Z

116

Tensile Effective Stresses in Hydrocarbon Storage Caverns  

E-Print Network (OSTI)

cycling in compressed air and natural gas storage in salt: Tracking stress states and cavern closure using.L., 2006.Geomechanical evaluation of two gulf coast natural gas storage caverns: Proceedings of the. (2011). More recently, Lux and Dresen (2012) analyzed high-frequency, cycled storage gas and noted

117

Proceedings: Steam Turbine Stress Corrosion Workshop  

Science Conference Proceedings (OSTI)

A recent survey of utilities commissioned by EPRI indicated that cracking of steam turbine disk rims by stress corrosion was a pervasive problem in both fossil and nuclear power plants. There is a clear need to document industry experience in this area so that guidelines can be provided to utilities on managing the problem.

1997-11-03T23:59:59.000Z

118

Jackknife empirical likelihood tests for error distributions in regression models  

Science Conference Proceedings (OSTI)

Regression models are commonly used to model the relationship between responses and covariates. For testing the error distribution, some classical test statistics such as Kolmogorov-Smirnov test and Cramer-von-Mises test suffer from the complicated limiting ... Keywords: Goodness-of-fit test, Jackknife empirical Likelihood method, Regression model, primary

Huijun Feng; Liang Peng

2012-11-01T23:59:59.000Z

119

A Quaternion Framework for Color Image Smoothing and Segmentation  

Science Conference Proceedings (OSTI)

In this paper, we present feature/detail preserving models for color image smoothing and segmentation using the Hamiltonian quaternion framework. First, we introduce a novel quaternionic Gabor filter (QGF) which can combine the color channels and the ... Keywords: Color image segmentation, Color image smoothing, Continuous mixture models, Directional distributions, Matrix-Fisher distribution, Quaternion Gabor filter, Quaternions, Watson distribution, von Mises distribution

Özlem N. Subakan; Baba C. Vemuri

2011-02-01T23:59:59.000Z

120

HUMBOLDTD i e Z e i t u n g d e r A l m a M a t e r B e r o l i n e n s i s Auf den Spuren von Lepsius  

E-Print Network (OSTI)

Bereich Studium und Praktikum im Ausland wird der Deutsche Akademische Austauschdienst vertreten sein. Konzepte der klassischen Chemie und der Oberflächenchemie sollen mit dem kreativen Einsatz natürlicher und, Institut für Chemie, für seine Arbeit ,,Heterodinukleare Molyb dän/BismutOrganyle ­ Von Bananenbin dungen

Röder, Beate

Note: This page contains sample records for the topic "von mises stress" 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

Aspects of Stress Corrosion Cracking Relevant to Irradiation-Assisted Stress Corrosion Cracking (IASCC)  

Science Conference Proceedings (OSTI)

This report provides a comprehensive survey of crack initiation issues in irradiation-assisted stress corrosion cracking (IASCC). It considers microcracking on smooth specimens and the transition from microcracking to stable crack propagation.

2002-05-02T23:59:59.000Z

122

Objective measures, sensors and computational techniques for stress recognition and classification: A survey  

Science Conference Proceedings (OSTI)

Stress is a major growing concern in our day and age adversely impacting both individuals and society. Stress research has a wide range of benefits from improving personal operations, learning, and increasing work productivity to benefiting society - ... Keywords: Computational stress model, Pattern recognition, Stress classification, Stress computational techniques, Stress prediction, Stress sensors

Nandita Sharma; Tom Gedeon

2012-12-01T23:59:59.000Z

123

Stress Test At Coso Geothermal Area (2004) | Open Energy Information  

Open Energy Info (EERE)

Stress Test At Coso Geothermal Area (2004) Stress Test At Coso Geothermal Area (2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Stress Test At Coso Geothermal Area (2004) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Stress Test Activity Date 2004 Usefulness not indicated DOE-funding Unknown Exploration Basis EGS potential of Coso Geothermal Region Notes A hydraulic fracturing stress test at 3,703 feet TVD was used to constrain a normal faulting and strike-slip faulting stress tensor for this reservoir. The shear and normal stresses resolved on the fracture and fault planes were calculated and used to identify the subset of critically stressed planes that act to maintain permeability within the Coso Geothermal Field. References

124

Global Wind Stress and Sverdrup Circulation from the Seasat Scatterometer  

Science Conference Proceedings (OSTI)

Three months of vector wind observations from the Seasat-A satellite scatterometer (SASS) are used to construct gridded fields of monthly average wind stress and wind stress curl over the global ocean. These fields are examined to identify ...

Dudley B. Chelton; Alberto M. Mestas-Nuñez; Michael H. Freilich

1990-08-01T23:59:59.000Z

125

Corrosion Fatigue Crack Growth and Stress-Corrosion Cracking in ...  

Science Conference Proceedings (OSTI)

Abstract Scope, The high stress ratio (R=0.85) corrosion fatigue crack growth kinetics and stress-corrosion cracking resistance of sensitized (70-175 °C up to ...

126

Statistical Characterization of Zonal and Meridional Ocean Wind Stress  

Science Conference Proceedings (OSTI)

Four years of ocean vector wind data are used to evaluate statistics of wind stress over the ocean. Raw swath wind stresses derived from the Quick Scatterometer (QuikSCAT) are compared with five different global gridded wind products, including ...

Sarah T. Gille

2005-09-01T23:59:59.000Z

127

Growth strains and stress relaxation in alumina scales during high temperature oxidation  

E-Print Network (OSTI)

combine with thermal stresses that develop during cooling toConsequently, thermal stresses build up on cooling withoutduring cooling and that the stresses resulting from thermal

Hou, P.Y.; Paulikas, A.P.; Veal, B.W.

2004-01-01T23:59:59.000Z

128

Using in Situ Thin Film Stress Measurements to Understand ...  

Science Conference Proceedings (OSTI)

Symposium, Nanostructured Materials for Lithium Ion Batteries and for Supercapacitors. Presentation Title, Using in Situ Thin Film Stress Measurements to ...

129

Residual Stress Tensor in a Compact Tension Weld Specimen  

Science Conference Proceedings (OSTI)

Presentation Title, Residual Stress Tensor in a Compact Tension Weld Specimen ... austenitic stainless steel (Esshete 1250) compact tension weld specimen.

130

Stress Corrosion Cracking of Steel In Concentrated Nitrate ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2011. Symposium, Environmentally Assisted Cracking of Materials. Presentation Title, Stress ...

131

Stress Corrosion Cracking Observation in API G-105 Grade Drill ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2011. Symposium, Environmentally Assisted Cracking of Materials. Presentation Title, Stress ...

132

stress corrosion cracking of iron and nickel based alloys  

Science Conference Proceedings (OSTI)

This Table of Contents is from Chemistry and Electrochemistry of Corrosion and Stress Corrosion Cracking published by TMS.

133

Aging Effects on Craze Growth Under Stress Relaxation ...  

Science Conference Proceedings (OSTI)

Aging Effects on Craze Growth Under Stress Relaxation Conditions. Mats Delin and Gregory B. McKenna, Polymers Division ...

134

1 INTRODUCTION Stressing brittle rocks leads to the development of  

E-Print Network (OSTI)

-dependent creep driven by stress corrosion and subcritical crack growth (Lockner, 1998). This creep strongly1 INTRODUCTION Stressing brittle rocks leads to the development of distributed damage long before, 1994, Lyakhovsky et al. 1997; Lockner, 1998). Further, the stress-induced damage may facilitate time

Ze'ev, Reches

135

Speech stress assessment using physiological and psychological measures  

Science Conference Proceedings (OSTI)

Emotional stress is commonly experienced while speaking in public, producing changes to the various speech productions subsystems, affecting the speech signal in predictable ways and being easily conveyed to listeners. Speech stress indicators, however, ... Keywords: emotion recognition, methodology, physiological sensors, speech corpus, stress assessment

Ana C. Aguiar, Mariana Kaiseler, Hugo Meinedo, Traian E. Abrudan, Pedro R. Almeida

2013-09-01T23:59:59.000Z

136

Analysis of low stress oil shale Hugoniots  

SciTech Connect

Analysis of low stress Hugoniot data on Anvil Points oil shale was accomplished through careful categorization of data depending upon density. Density is directly related to kerogen content and kerogen content is a strong variable in determining the Hugoniot. For a given density (kerogen content), the shock velocity-particle velocity data show a minimum in shock velocity believed related to yielding in the rock constituent of the oil shale. Low stress Hugoniot data blend smoothly with high pressure data. Further data selection permitted evaluation of the orientation dependence (approximately 15 percent in wave speed) of the shock velocity. Wave propagation speed in a direction normal to the bedding planes is less than that parallel to the bedding planes. A weak minimum in wave speed occurs between 0 and 45/sup 0/.

Munson, D.E.

1977-10-01T23:59:59.000Z

137

U.S. West Coast Surface Heat Fluxes, Wind Stress, and Wind Stress Curl from a Mesoscale Model  

Science Conference Proceedings (OSTI)

Monthly averages of numerical model fields are beneficial for depicting patterns in surface forcing such as sensible and latent heat fluxes, wind stress, and wind stress curl over data-sparse ocean regions. Grid resolutions less than 10 km ...

T. Haack; S. D. Burk; R. M. Hodur

2005-11-01T23:59:59.000Z

138

Alexander von Scheven  

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

, PhD student at the Department for Renewable Energy Resources, Darmstadt University of Technology, Germany This Speaker's Seminars E-Energy - Implementing Smart Grids in Germany...

139

Spurensuche Kommilitonen von 1933  

E-Print Network (OSTI)

.400 Physiker. Dreizehn deutsche Ins- titute wirken dabei mit und werden vom Bundesministerium für Bildung und Uhr. Ziel ist es, jene Zeit gezielt zu erforschen, in der christlich-deutsche und jüdisch- deutsche Daten ausgeführt. Den Betrieb solcher Cloud-Rechner übernehmen Drittfirmen. Chemie-Preis Christian

Röder, Beate

140

Vibration and Structural Response of Hybrid Wind Turbine Blades  

E-Print Network (OSTI)

Renewable energy is a serious alternative to deliver the energy needs of an increasing world population and improve economic activity. Wind energy provides better environmental and economic benefits in comparison with the other renewable energy sources. Wind energy is capable of providing 72 TW (TW = 10^12 W) of electric power, which is approximately four and half times the world energy consumption of 15.8 TW as reported in 2006. Since power output extracted from wind turbines is proportional to the square of the blade length and the cube of the wind speed, wind turbine size has grown rapidly in the last two decades to match the increase in power output. As the blade length increases, so does its weight opening up design possibilities to introduce hybrid glass and carbon fiber composite materials as lightweight structural load bearing alternatives. Herein, we investigate the feasibility of introducing modular composite tubulars as well as hybrid sandwich composite skins in the next generation blades. After selecting a target energy output, 8 MW with 80 m blade, airfoil geometry and the layup for the skin as well as internal reinforcements are proposed. They are incorporated into the computational blade via linear shell elements for the skin, and linear beam elements for the composite tubulars to assess the relationship between weight reduction and structural performance. Computational simulations are undertaken to understand the static and dynamic regimes; specifically, displacements, stresses, and vibration modes. The results showed that the composite layers did not exhibit any damage. However, in the balsa core of the sandwich skin, the von Mises stress exceeded its allowable at wind speeds ranging from 11.0 m/sec to 12.6 m/sec. In the blades with composite tubular reinforcement, two different types of damage are observed: a. Stress concentrations at the tubular-skin attachments, and b. Highest von Mises stress caused by the flapping bending moment. The vibration studies revealed a strong coupling mode, bending and twist, at the higher natural frequencies of the blade with tubular truss configuration. The weight saving measures in developing lighter blades in this study did not detract from the blades structural response for the selected load cases.

Nanami, Norimichi

2010-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

From Maxwell Stresses to Nonlinear Field Equations  

E-Print Network (OSTI)

This paper aims to show that making use of Newton's view on equations of motion of a physical system and of the Maxwell stress tensor we come to a natural nonlinearization of Maxwell equations in vacuum making use only of nonrelativistic terms. The new equations include all Maxwell solutions plus new ones, among which one may find time-stable and spatially finite ones with photon-like properties and behavior.

Donev, S; Donev, Stoil; Tashkova, Maria

2006-01-01T23:59:59.000Z

142

From Maxwell Stresses to Nonlinear Field Equations  

E-Print Network (OSTI)

This paper aims to show that making use of Newton's view on equations of motion of a physical system and of the Maxwell stress tensor we come to a natural nonlinearization of Maxwell equations in vacuum making use only of nonrelativistic terms. The new equations include all Maxwell solutions plus new ones, among which one may find time-stable and spatially finite ones with photon-like properties and behavior.

Stoil Donev; Maria Tashkova

2006-04-04T23:59:59.000Z

143

PNNL Stress/Strain Correlation for Zircaloy  

Science Conference Proceedings (OSTI)

Pacific Northwest National Laboratory (PNNL) was tasked with incorporating cladding mechanical property data into the Nuclear Regulatory Commission (NRC) fuel codes, FRAPCON-31 and FRAPTRAN2, by the NRC Office of Nuclear Reactor Research. The objective of that task was to create a mechanical model that can calculate true stress, true strain, and the possible failure of the fuel rod cladding based on uniaxial test data.

Geelhood, Kenneth J.; Beyer, Carl E.; Luscher, Walter G.

2008-07-18T23:59:59.000Z

144

Stress Indices for Elbows with Trunnion Attachments  

Science Conference Proceedings (OSTI)

Trunnions on elbows are generally used as supports and are also used in some applications as anchors. The qualification of trunnions is an important item in the design and fitness-for-service of many piping systems. This report provides equations, based on experimental and test data, for determining the stress indices, B and C, and the flexibility factor, k, for elbows with hollow circular cross-section attachments (trunnions). The report contains explicit modifications to ASME Code Cases 391 and 392 for...

1998-12-15T23:59:59.000Z

145

Controlling Residual Stresses by Heat Sink Welding  

Science Conference Proceedings (OSTI)

Results are described of a combined finite element and pipe welding study in which the welding and heat sink parameters required to optimize fast pass heat sink welding (LPHSW) were identified and evaluated in analytic and experimental tasks. Also discussed is the application of an elastic-plastic finite element computer code model to evaluate and optimize the LPHSW process and to verify the results through residual stress measurements on LPHSW pipes.

1981-12-01T23:59:59.000Z

146

Thin Silicon MEMS Contact-Stress Sensor  

SciTech Connect

This work offers the first, thin, MEMS contact-stress (CS) sensor capable of accurate in situ measruement of time-varying, contact-stress between two solid interfaces (e.g. in vivo cartilage contact-stress and body armor dynamic loading). This CS sensor is a silicon-based device with a load sensitive diaphragm. The diaphragm is doped to create piezoresistors arranged in a full Wheatstone bridge. The sensor is similar in performance to established silicon pressure sensors, but it is reliably produced to a thickness of 65 {micro}m. Unlike commercial devices or other research efforts, this CS sensor, including packaging, is extremely thin (< 150 {micro}m fully packaged) so that it can be unobtrusively placed between contacting structures. It is built from elastic, well-characterized materials, providing accurate and high-speed (50+ kHz) measurements over a potential embedded lifetime of decades. This work explored sensor designs for an interface load range of 0-2 MPa; however, the CS sensor has a flexible design architecture to measure a wide variety of interface load ranges.

Kotovsky, J; Tooker, A; Horsley, D A

2009-12-07T23:59:59.000Z

147

Surface stress effects on indentation fracture sequences  

Science Conference Proceedings (OSTI)

Ion exchange was used to introduce surface compression in soda-lime-silica glass (SLS) and aluminosilicate glass (ALS). In situ observations of the indentation cracking sequences on the modified surfaces were made and compared with those on the base glasses. The initiation point for each crack type formed during the loading and unloading cycle was monitored on the indenter load-displacement traces. On the base glasses, median (in the SLS) and cone (in the ALS) cracking was observed during the loading cycle. Modified median, radial, and lateral cracking was observed in both glasses during unloading. The introduction of the residual compressive surface stress was found to completely suppress all cracking during the loading cycle (up to 100 N) in both the SLS and ALS. In addition, the initiation of the cracks formed during the unloading cycle was shifted to further down in the cycle, i.e., to lower values of the initiation load. A pronounced tendency for a shift in the cracking from median to radial was also observed on the residually stressed surfaces. A similar shift was observed on stress-free surfaces during unloading as the value of the initiation load decreased for a given peak load.

Tandon, R.; Green, D.J. (Dept. of Materials Science and Engineering, Pennsylvania State Univ., University Park, PA (US)); Cook, R.F. (IBM Research Div., T.J. Watson Research Center, Yorktown Heights, NY (US))

1990-09-01T23:59:59.000Z

148

PRIORITY COMMUNICATION Maternal Stress Beginning in Infancy May Sensitize Children to Later Stress Exposure: Effects on Cortisol and Behavior*  

E-Print Network (OSTI)

neonatal environment can permanently alter an individual’s responses to stress. To demonstrate a similar phenomenon in humans, we prospectively examined the relationships of maternal stress beginning in infancy and concurrent stress on preschoolers ’ hypothalamic-pituitary-adrenal activity and later mental health symptoms. Methods: Salivary cortisol levels were assessed in 282 4.5-year-old children and 154 of their siblings. Maternal reports of stress were obtained when the children were ages 1, 4, and 12 months, and again at 4.5 years. Children’s mental health symptoms were assessed in first grade. Results: A cross-sectional analysis revealed that preschoolers exposed to high levels of concurrent maternal stress had elevated cortisol levels; however, a longitudinal analysis revealed that concurrently stressed children with elevated cortisol also had a history of high maternal stress exposure in infancy. Importantly, children exposed only to high levels of concurrent or early stress had cortisol levels that did not significantly differ from those never exposed to stress. Further analysis of the components of stress indicated that maternal depression beginning in infancy was the most potent predictor of children’s cortisol. We also found that preschoolers with high cortisol levels exhibited greater mental health symptoms in first grade. Conclusions: These results link the findings of preclinical studies to humans by showing that exposure to early maternal stress may sensitize children’s pituitary-adrenal responses to subsequent stress exposure. Biol Psychiatry 2002;52:776–784 © 2002 Society of Biological Psychiatry

Marilyn J. Essex; Marjorie H. Klein; Eunsuk Cho; Ned H. Kalin

2002-01-01T23:59:59.000Z

149

Microseismicity, stress, and fracture in the Coso geothermal field,  

Open Energy Info (EERE)

Microseismicity, stress, and fracture in the Coso geothermal field, Microseismicity, stress, and fracture in the Coso geothermal field, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Microseismicity, stress, and fracture in the Coso geothermal field, California Details Activities (1) Areas (1) Regions (0) Abstract: Microseismicity, stress, and fracture in the Coso geothermal field are investigated using seismicity, focal mechanisms and stress analysis. Comparison of hypocenters of microearthquakes with locations of development wells indicates that microseismic activity has increased since the commencement of fluid injection and circulation. Microearthquakes in the geothermal field are proposed as indicators of shear fracturing associated with fluid injection and circulation along major pre-existing

150

Residual stress measurement and microstructural characterization of thick beryllium films  

SciTech Connect

Beryllium films are synthesized by a magnetron sputtering technique incorporating in-situ residual stress measurement. Monitoring the stress evolution in real time provides quantitative through-thickness information on the effects of various processing parameters, including sputtering gas pressure and substrate biasing. Specimens produced over a wide range of stress states are characterized via transmission and scanning electron microscopy, and atomic force microscopy, in order to correlate the stress data with microstructure. A columnar grain structure is observed for all specimens, and surface morphology is found to be strongly dependent on processing conditions. Analytical models of stress generation are reviewed and discussed in terms of the observed microstructure.

Detor, A; Wang, M; Hodge, A M; Chason, E; Walton, C; Hamza, A V; Xu, H; Nikroo, A

2008-02-11T23:59:59.000Z

151

Coronary Disease in Emergency Department Chest Pain Patients with Recent Negative Stress Testing  

E-Print Network (OSTI)

only stress tests or nuclear stress tests was available. Theon record, so some nuclear stress tests and ECG-only studiesor nuclear imaging. Official stress test reports provided at

Walker, Jonathan; Galuska, Michael; Vega, David

2010-01-01T23:59:59.000Z

152

Stress State of the Earth's Crust in Azerbaijan  

Science Conference Proceedings (OSTI)

The study of the crustal stress has a practical implication in hazard mitigation. Knowledge on stress-related ground motion may help to improve the stability of public and private buildings. The stress state of the crust in Azerbaijan is studied in this paper by means of focal mechanism analysis and using different methods to determine the principal stress orientations. Two types of stress states were revealed in the studied regions. The territory of Great and Lesser Caucasus and Talysh folded zone are characterized by near-horizontal compression. The territories of Caspian Sea and Kura depression are characterized by near-horizontal tension. For both types of stress state, the predominant stress axes are oriented perpendicular to the regional geological structures.

Agayeva, Solmaz T. [Geology Institute, Azerbaijan National Academy of Sciences, 29A, H. Javid Ave., Baku 1143 (Azerbaijan)

2006-03-23T23:59:59.000Z

153

Load partitioning in honycomb-like silicon carbide aluminum alloy composites.  

DOE Green Energy (OSTI)

A 50/50 vol.% Al/SiC composite was made via melt infiltration of an aluminum alloy into a porous beech wood-derived SiC preform. The honeycomb-like composite microstructure consisted of an interconnected SiC phase surrounding discrete Al 'fibers' aligned in the growth direction of the beech wood. High energy synchrotron X-ray diffraction was used to measure the volume averaged lattice strains in both the SiC and Al phases during in situ compressive loading up to an applied stress of -530MPa. Load transfer from the Al to the SiC was observed, and the Al yielded at an applied stress of above -213MPa. The elastic behavior of the composite was modeled with both an isostrain rule of mixtures calculation and variational bounds for the effective elastic modulus. Furthermore, calculations of the von Mises effective stress of the SiC and Al phases showed that the wood-derived SiC was a more effective reinforcement than either SiC particle- or whisker-reinforced composites.

Wikes, T. E.; Harder, B. J.; Almer, J. D.; Faber, K. T.; Northwestern Univ.

2009-01-01T23:59:59.000Z

154

Stress-Assisted Corrosion in Boiler Tubes  

Science Conference Proceedings (OSTI)

A number of industrial boilers, including in the pulp and paper industry, needed to replace their lower furnace tubes or decommission many recovery boilers due to stress-assisted corrosion (SAC) on the waterside of boiler tubes. More than half of the power and recovery boilers that have been inspected reveal SAC damage, which portends significant energy and economic impacts. The goal of this project was to clarify the mechanism of stress-assisted corrosion (SAC) of boiler tubes for the purpose of determining key parameters in its mitigation and control. To accomplish this in-situ strain measurements on boiler tubes were made. Boiler water environment was simulated in the laboratory and effects of water chemistry on SAC initiation and growth were evaluated in terms of industrial operations. Results from this project have shown that the dissolved oxygen is single most important factor in SAC initiation on carbon steel samples. Control of dissolved oxygen can be used to mitigate SAC in industrial boilers. Results have also shown that sharp corrosion fatigue and bulbous SAC cracks have similar mechanism but the morphology is different due to availability of oxygen during boiler shutdown conditions. Results are described in the final technical report.

Preet M Singh; Steven J Pawel

2006-05-27T23:59:59.000Z

155

Stress Intensity Factor Plasticity Correction for Flaws in Stress Concentration Regions  

DOE Green Energy (OSTI)

Plasticity corrections to elastically computed stress intensity factors are often included in brittle fracture evaluation procedures. These corrections are based on the existence of a plastic zone in the vicinity of the crack tip. Such a plastic zone correction is included in the flaw evaluation procedure of Appendix A to Section XI of the ASME Boiler and Pressure Vessel Code. Plasticity effects from the results of elastic and elastic-plastic explicit flaw finite element analyses are examined for various size cracks emanating from the root of a notch in a panel and for cracks located at fillet fadii. The results of these caluclations provide conditions under which the crack-tip plastic zone correction based on the Irwin plastic zone size overestimates the plasticity effect for crack-like flaws embedded in stress concentration regions in which the elastically computed stress exceeds the yield strength of the material. A failure assessment diagram (FAD) curve is employed to graphically c haracterize the effect of plasticity on the crack driving force. The Option 1 FAD curve of the Level 3 advanced fracture assessment procedure of British Standard PD 6493:1991, adjusted for stress concentration effects by a term that is a function of the applied load and the ratio of the local radius of curvature at the flaw location to the flaw depth, provides a satisfactory bound to all the FAD curves derived from the explicit flaw finite element calculations. The adjusted FAD curve is a less restrictive plasticity correction than the plastic zone correction of Section XI for flaws embedded in plastic zones at geometric stress concentrators. This enables unnecessary conservatism to be removed from flaw evaluation procedures that utilize plasticity corrections.

Friedman, E.; Wilson, W.K.

2000-02-01T23:59:59.000Z

156

Fundamental solutions for isotropic size-dependent couple stress elasticity  

E-Print Network (OSTI)

Fundamental solutions for two- and three-dimensional linear isotropic size-dependent couple stress elasticity are derived, based upon the decomposition of displacement fields into dilatational and solenoidal components. While several fundamental solutions have appeared previously in the literature, the present version is for the newly developed fully determinate couple stress theory. Within this theory, the couple stress tensor is skewsymmetrical and thus possesses vectorial character. The present derivation provides solutions for infinite domains of elastic materials under the influence of unit concentrated forces and couples. Unlike all previous work, unique solutions for displacements, rotations, force-stresses and couple-stresses are established, along with the corresponding force-tractions and couple-tractions. These fundamental solutions are central in analysis methods based on Green's functions for infinite domains and are required as kernels in the corresponding boundary integral formulations for size-dependent couple stress elastic materials.

Ali R. Hadjesfandiari; Gary F. Dargush

2011-07-14T23:59:59.000Z

157

Assessment of the Mechanical Stress Improvement Process for Mitigating Primary Water Stress Corrosion Cracking in Nickel Alloy Butt Welds in Piping Systems Approved for Leak-Before-Break  

SciTech Connect

This report provides an assessment of the use of Mechanical Stress Improvement Process to reduce, or decrease, stress-driven degradation, i.e., primary water stress corrosion cracking.

Sullivan, Edmund J.; Anderson, Michael T.

2013-01-01T23:59:59.000Z

158

Relationships Between Stress Corrosion Cracking Tests and Utility ...  

Science Conference Proceedings (OSTI)

Aug 1, 1999 ... Several utility steam generator and stress corrosion cracking ... Superheated steam and neutral solution environments are found to be ...

159

Residual Stress Determination in Cast Bi-Metallic Joints  

Science Conference Proceedings (OSTI)

In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium · In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.

160

Determination of the recovery stresses developed by shape memory alloys  

SciTech Connect

A simple relationship has been developed between recovery stresses, temperature, and strain, to explain the mechanical shape memory effect in some alloys which undergo thermoelastic martensitic transformation. (GHT)

Mohamed, H.A.

1978-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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.
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161

Pressure vessel reliability as a function of allowable stress  

SciTech Connect

From Winter meeting of American Society of Mechanical Engineers; Detroit, Michigan, USA (11 Nov 1973). The probability of failure corresponding to specified levels of allowable design stress was calculated for pressure vessels designed in accordance with the ASME Boiler and Pressure Vessel Code. The analysis was performed for maximum shear stress failure and for cyclic stress failure. The significance of such failure prediction is ddscussed and a rationale for selecting an allowable stress is presented. Examples are presented that demonstrate the estimation of vessel failure probability as a function of load variation, strength variation, and design safety factor. (auth)

Arnold, H.G.

1972-01-01T23:59:59.000Z

162

Correlation of the stress to rupture data of Incoloys  

SciTech Connect

This paper reports on the application of a phenomenological approach for correlating the stress-to-rupture date of Incoloys which is in part based on the load relaxation behavior of the same material. An effective strain rate was calculated from the literature stress-to-rupture data. The resulting log modulus normalized stress vs log effective strain rate curves of different temperatures were translated to form a master composite curve. The master composite curve was found to exhibit qualitatively the same shape as the log stress vs log non-elastic strain rate curve obtained in the load relaxation test. The master composite curve was used as the basis for data correlation.

Wilson, H.; Suzuki, H.; Li, C.Y.

1983-01-01T23:59:59.000Z

163

Mathematical Modeling of Spooling/Unspooling Stresses in ...  

Science Conference Proceedings (OSTI)

Presentation Title, Mathematical Modeling of Spooling/Unspooling Stresses in Electricity Distribution Cables. Author(s), James W. Evans, W. Kinzy Jones, Jr.

164

Stress Effect on Charge and Discharge Rate and Energy Efficiency ...  

Science Conference Proceedings (OSTI)

Presentation Title, Stress Effect on Charge and Discharge Rate and Energy Efficiency of Li-alloy Electrodes. Author(s), Yifan Gao, Min Zhou. On-Site Speaker

165

Fracture Permeability and In Situ Stress in the Dixie Valley...  

Open Energy Info (EERE)

Reservoir Abstract Borehole televiewer, temperature and flowmeter logs and hydraulic fracturing stress measurements conducted in six wells penetrating a geothermal reservoir...

166

Stress Corrosion Cracking of Stabilized Austenitic Stainless Steels ...  

Science Conference Proceedings (OSTI)

Aug 1, 1999 ... Stress Corrosion Cracking of Stabilized Austenitic Stainless Steels in Various Types of Nuclear Power Plants by M.O. Speidel and R.

167

Analysis of local stress distribution in a metal gate MOSFET ...  

Science Conference Proceedings (OSTI)

... Raman spectroscopy is a promising technique for stress analysis in Si devices Non-destructive, non-contact Bulk sample cf TEM ... Ram an Sh ift (c ...

2013-03-29T23:59:59.000Z

168

Neutron Stress, Texture, and Phase Transformation for Industry...  

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

NST2 Neutron Stress, Texture, and Phase Transformation for Industry April 19, 2007 Spallation Neutron Source Oak Ridge National Laboratory, Oak Ridge, TN Presentation PDF's & Group...

169

Prediction of corn tortilla textural quality using stress relaxation methods.  

E-Print Network (OSTI)

??Feasibility of the stress relaxation technique which has a strong potential for texture characterization of dough and food products, was evaluated with both corn masa… (more)

Guo, Zhihong

2012-01-01T23:59:59.000Z

170

Challenges and Solutions to TGO Stress Measurement in Engine ...  

Science Conference Proceedings (OSTI)

Presentation Title, Challenges and Solutions to TGO Stress Measurement in Engine Run Gas Turbine Components. Author(s), Eric H Jordan, Mark S Majewski, ...

171

Influence of Interstitial Content and Stress State of the Shock ...  

Science Conference Proceedings (OSTI)

Presentation Title, Influence of Interstitial Content and Stress State of the Shock- Induced Phase Transitions in Zr, Ti, and Fe. Author(s), George Thompson Gray, ...

172

Plastic Strain and Residual Stress Distributions in an AISI 304 ...  

Science Conference Proceedings (OSTI)

Effect of DH Concentration on Crud Deposition on Heated Zircaloy-4 in .... and Residual Stress Distributions in an AISI 304 Stainless Steel BWR Pipe Weld.

173

In-vitro Evaluation of Stress Corrosion Cracking of Biomedical ...  

Science Conference Proceedings (OSTI)

In this study, the susceptibility to stress corrosion cracking of biodegradable and aluminium-free magnesium alloys, WZ21 and WE43, was investigated using ...

174

Corrosion Inhibition of Stress Corrosion Cracking and Localized ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Stress corrosion cracking of 7050 aluminum alloys in the turbo expander industry can cause expensive catastrophic failures, especially for turbo

175

Strain Rate Sensitivity of Alloy 718 Stress Corrosion Cracking  

Science Conference Proceedings (OSTI)

Stress corrosion cracking (SCC) tests were conducted in 36O'C pressurized- water-reactor. (PWR) primary water using. Alloy 718 heat-treated to produce.

176

Stress Corrosion Cracking of Aluminium-Free Magnesium Alloys in ...  

Science Conference Proceedings (OSTI)

Presentation Title, Stress Corrosion Cracking of Aluminium-Free Magnesium Alloys in a Simulated Human Body Fluid. Author(s), Lokesh Choudhary, R. K. Singh ...

177

Stress Corrosion Crack Initiation of Alloy 690 in Subcritical and ...  

Science Conference Proceedings (OSTI)

Abstract Scope, The objective of this study is to investigate the structure and chemistry of corrosion and stress corrosion crack initiation in Alloy 690. To avoid

178

grain boundary oxidation and stress corrosion cracking in nickel ...  

Science Conference Proceedings (OSTI)

Accelerated stress corrosion cracking tests and exposures were conducted on alloy 600, Ni-9Fe, and Ni-9Fe-5Cr (LCr) in constant extension rate mode in ...

179

Stress Corrosion Cracking Threshold of Ti 6-4 Extrusions  

Science Conference Proceedings (OSTI)

Ti 6Al-4V extrusions with standard chemistry and extra low interstitial are evaluated for their stress corrosion cracking resistance. Also examined is the affect of ...

180

A Study on the Stress Corrosion Cracking Mechanism of Carbon ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Carbon steel is susceptible to stress corrosion cracking (SCC) in fuel grade ethanol (FGE). The research results obtained thus far have found ...

Note: This page contains sample records for the topic "von mises stress" 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

Stress Corrosion Cracking Initiation of Austenitic Alloys in ...  

Science Conference Proceedings (OSTI)

Presentation Title, Stress Corrosion Cracking Initiation of Austenitic Alloys in Supercritical Water. Author(s), Guoping Cao, Vahid Firouzdor, Todd Allen. On-

182

Galvanic Corrosion and Stress Corrosion Cracking of Steel and ...  

Science Conference Proceedings (OSTI)

No aluminum bolt AW 7075 failed in magnesium due to stress corrosion cracking (SCC). Even aluminum bolts in T6 condition can be used for automotive ...

183

Residual Stresses in Semi-permanent Mold Engine Head Castings  

Science Conference Proceedings (OSTI)

One casting was quenched using water and the other was air quenched. ... the intake and exhaust valve ports indicating the main differences in strain/stress ...

184

Stress Analysis and Deformation Prediction of A Heavy Hydraulic ...  

Science Conference Proceedings (OSTI)

The coupling analysis of heat transfer, phase transformation and stress in heat treatment process of the turbine blade for Three Gorges Project is carried out by ...

185

One-Dimensional Cold Rolling Effects on Stress Corrosion Crack ...  

Science Conference Proceedings (OSTI)

A Microstructural Investigation on the Effect of Cold Work on Environmentally .... Stress Corrosion Cracking Behavior near the Fusion Boundary of Dissimilar ...

186

Seismicity and seismic stress in the Coso Range, Coso geothermal...  

Open Energy Info (EERE)

California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Book: Seismicity and seismic stress in the Coso Range, Coso geothermal field, and Indian...

187

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

188

Investigation of Residual Stress in Key-Hole Laser Formed ...  

Science Conference Proceedings (OSTI)

Residual strain/stress measurements in weldments produced using the fibre ... Dislocation Densities, Burgers Vector Populations and Slip System Activity in ...

189

Stress and Fracture of Silicon Solar Cells as Revealed by ...  

Science Conference Proceedings (OSTI)

Presentation Title, Stress and Fracture of Silicon Solar Cells as Revealed by ... thinner and thinner silicon in the solar photovoltaic (PV) technologies due to the ...

190

NRC/EPRI Welding Residual Stress Validation Program (Phase III)  

Science Conference Proceedings (OSTI)

The NRC/EPRI weld residual stress (WRS) program currently consists of four phases, with each phase increasing in complexity from lab size specimens to ...

191

Downsizing and the Metals Executive: Handling the Stress  

Science Conference Proceedings (OSTI)

Stress among managers led to two resignations. When two major customers left, the board asked the president to resign. A new president, after six months, still ...

192

P wave anisotropy, stress, and crack distribution at Coso geothermal...  

Open Energy Info (EERE)

P wave anisotropy, stress, and crack distribution at Coso geothermal field, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: P wave...

193

Thin Silicon MEMS Contact-Stress Sensor  

SciTech Connect

This thin, MEMS contact-stress (CS) sensor continuously and accurately measures time-varying, solid interface loads in embedded systems over tens of thousands of load cycles. Unlike all other interface load sensors, the CS sensor is extremely thin (< 150 {micro}m), provides accurate, high-speed measurements, and exhibits good stability over time with no loss of calibration with load cycling. The silicon CS sensor, 5 mm{sup 2} and 65 {micro}m thick, has piezoresistive traces doped within a load-sensitive diaphragm. The novel package utilizes several layers of flexible polyimide to mechanically and electrically isolate the sensor from the environment, transmit normal applied loads to the diaphragm, and maintain uniform thickness. The CS sensors have a highly linear output in the load range tested (0-2.4 MPa) with an average accuracy of {+-} 1.5%.

Kotovsky, J; Tooker, A; Horsley, D

2010-03-22T23:59:59.000Z

194

Adjustable shear stress erosion and transport flume  

DOE Patents (OSTI)

A method and apparatus for measuring the total erosion rate and downstream transport of suspended and bedload sediments using an adjustable shear stress erosion and transport (ASSET) flume with a variable-depth sediment core sample. Water is forced past a variable-depth sediment core sample in a closed channel, eroding sediments, and introducing suspended and bedload sediments into the flow stream. The core sample is continuously pushed into the flow stream, while keeping the surface level with the bottom of the channel. Eroded bedload sediments are transported downstream and then gravitationally separated from the flow stream into one or more quiescent traps. The captured bedload sediments (particles and aggregates) are weighed and compared to the total mass of sediment eroded, and also to the concentration of sediments suspended in the flow stream.

Roberts, Jesse D. (Carlsbad, NM); Jepsen, Richard A. (Carlsbad, NM)

2002-01-01T23:59:59.000Z

195

Characterization of Optical Fiber Strength Under Applied Tensile Stress and Bending Stress  

Science Conference Proceedings (OSTI)

Various types of tensile testing and bend radius tests were conducted on silica core/silica cladding optical fiber of different diameters with different protective buffer coatings, fabricated by different fiber manufacturers. The tensile tests were conducted to determine not only the average fiber strengths at failure, but also the distribution in fracture strengths, as well as the influence of buffer coating on fracture strength. The times-to-failure of fiber subjected to constant applied bending stresses of various magnitudes were measured to provide a database from which failure times of 20 years or more, and the corresponding minimum bend radius, could be extrapolated in a statistically meaningful way. The overall study was done to provide an understanding of optical fiber strength in tensile loading and in applied bending stress as related to applications of optical fiber in various potential coizfgurations for weapons and enhanced surveillance campaigns.

P.E. Klingsporn

2011-08-01T23:59:59.000Z

196

Post-traumatic stress disorder: opportunities & challenges for computing technology  

Science Conference Proceedings (OSTI)

Post-Traumatic Stress Disorder (PTSD) is a condition in which a person responds to a traumatic event, such as war, a car accident, or physical abuse, with prolonged feelings of fear, helplessness, or horror. This disorder can have a significant detrimental ... Keywords: healthcare, mental disorders, mental health, mobile technologies, post-traumatic stress disorder, ptsd, tele-health, trauma, veterans

Brian M. Landry; Eun Kyoung Choe; Stephen McCutcheon; Julie A. Kientz

2010-11-01T23:59:59.000Z

197

Occult hemoglobin as an indicator of impingement stress in fishes  

SciTech Connect

During the process of impingement on cooling system intake screens, fish may be subject to different types of stress, the total of which often results in the death of individual fish. This report assesses the use of occult hemoglobin in fish demand mucus as an indicator of impingement stress. (ACR)

Not Available

1980-01-01T23:59:59.000Z

198

A characterization of the electromagnetic stress-energy tensor  

E-Print Network (OSTI)

In a previous paper, we pointed out how a dimensional analysis of the stress-energy tensor of the gravitational field allows to derive the field equation of General Relativity. In this note, we comment an analogous reasoning in presence of a 2-form, that allows to characterize the so called electromagnetic stress-energy tensor.

J. Navarro; J. B. Sancho

2011-01-13T23:59:59.000Z

199

Visualization and Numerical Analysis of Stress Waves in Blasting Process  

Science Conference Proceedings (OSTI)

Visualization studies were performed both experimentally and theoretically to observe stress wave propagation in a material and its interaction with the free surface of the material in a blasting process. PMMA (polymethyl-methacrylate) plates were used ... Keywords: Explosives, Shadowgraphy, Smoothed particle hydrodynamics, Stress waves

S. Matsumoto; Y. Nakamura; S. Itoh

2003-08-01T23:59:59.000Z

200

Rheopexy and tunable yield stress of carbon black suspensions  

E-Print Network (OSTI)

We show that besides simple or thixotropic yield stress fluids there exists a third class of yield stress fluids. This is illustrated through the rheological behavior of a carbon black suspension, which is shown to exhibit a viscosity bifurcation effect around a critical stress along with rheopectic trends, i.e., after a preshear at a given stress the fluid tends to accelerate when it is submitted to a lower stress. Viscosity bifurcation displays here original features: the yield stress and the critical shear rate depend on the previous flow history. The most spectacular property due to these specificities is that the material structure can be adjusted at will through an appropriate flow history. In particular it is possible to tune the material yield stress to arbitrary low values. A simple model assuming that the stress is the sum of one component due to structure deformation and one component due to hydrodynamic interactions predicts all rheological trends observed and appears to well represent quantitatively the data.

Guillaume Ovarlez; Laurent Tocquer; François Bertrand; Philippe Coussot

2012-11-16T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Stress Intensification Factors and Flexibility Factors for Unreinforced Branch Connections  

Science Conference Proceedings (OSTI)

This report provides equations, based on analyses and test data, for determining the stress intensification factors and flexibility factors for branch connections. The report contains results of an investigation into the flexibility and stress intensification factors of unreinforced fabricated tees (and other similar configurations). It provides flexibility equations for a more accurate evaluation of these configurations.

1998-11-23T23:59:59.000Z

202

Secretary Chu Stresses Global Cooperation on Energy, Economic and Climate  

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

Stresses Global Cooperation on Energy, Economic and Stresses Global Cooperation on Energy, Economic and Climate Challenges in Talks with World Energy Ministers Secretary Chu Stresses Global Cooperation on Energy, Economic and Climate Challenges in Talks with World Energy Ministers March 13, 2009 - 12:00am Addthis Washington, DC - In recent discussions with a broad range of world energy ministers, U.S. Energy Secretary Steven Chu has stressed the need for global cooperation on energy, economic and climate challenges. Over the past several weeks, Secretary Chu's dialogue with representatives of both energy producing and consuming nations has reinforced the Obama Administration's commitment to energy independence and stressed the shared opportunities to create jobs and boost the global economy through energy

203

CASMI-A visualization tool for the World Stress Map database  

Science Conference Proceedings (OSTI)

The World Stress Map (WSM) project has compiled a global database of quality-ranked data records on the contemporary tectonic stresses in the Earth's crust. The WSM 2005 database release contains approximately 16000 data records from different types ... Keywords: Database, Stress indicators, Stress map, Tectonic stress

Oliver Heidbach; Jens Höhne

2008-07-01T23:59:59.000Z

204

Bias-Stress Effect in Pentacene Organic Thin-Film Transistors  

E-Print Network (OSTI)

The effects of bias stress in integrated pentacene organic transistors are studied and modeled for different stress conditions. It is found that the effects of bias stress can be expressed in terms of the shift in applied ...

Ryu, Kevin K.

205

Materials Reliability Program: Weld Residual Stress Measurement and Implications for Stress Corrosion Testing (MRP-282)  

Science Conference Proceedings (OSTI)

Primary water stress corrosion cracking (PWSCC) data for heat-affected zones (HAZs) in thick-walled components of both Alloy 600 and Alloy 690TT are needed to support the Materials Reliability Program (MRP) crack growth rate (CGR) disposition relationship for Alloy 600 (EPRI report 1006695, MRP-55 Revision 1). Such data are also needed to ensure that welding of Alloy 690TT does not deleteriously affect its inherent resistance to PWSCC. Various welded plates of both Alloy 600 and Alloy 690TT were produced...

2010-08-02T23:59:59.000Z

206

Investigation of Stress Indices and Directional Loading of Eccentric Reducers  

Science Conference Proceedings (OSTI)

Engineering for fatigue is an essential concern in piping systems. Addressing this concern, the ASME Section III and ANSI B31.1 Codes provide stress indices and stress intensification factors (SIFs) to be used in the design and evaluation of Class 1, 2, and 3 systems. In recent research cosponsored by EPRI and the U.S. Department of Energy (DOE), new test data have been developed for comparison with the ASME stress indices and SIFs. This report presents the results of fatigue tests on eccentric reducers,...

2003-08-11T23:59:59.000Z

207

Manipulating Stress in Cu/low-k Dielectric Nanocomposites  

Science Conference Proceedings (OSTI)

The interaction of x-rays with organic dielectric materials, which alters their mechanical properties, affects values of stress generated within encapsulated Cu structures. In particular, the evolution of stress within submicron Cu interconnect structures encapsulated by an organosilicate glass can be investigated in situ using synchrotron-based x-ray diffraction. The overall geometry of the composite, along with the amount of irradiation, dictates the change in stress of the Cu features. A quantitative comparison of these findings to mechanical modeling results reveals two modes of modification within the dielectric film: a densification that changes the effective eigenstrain followed by an increase in elastic modulus.

C Murray; P Besser; E Ryan; J Jordan-Sweet

2011-12-31T23:59:59.000Z

208

Neutron Diffraction Studies of the Tri-axial Stress Distribution in ...  

Science Conference Proceedings (OSTI)

Here neutron diffraction strain scanning, originally developed for residual stress measurements, is applied to the stress distribution in granular materials under a ...

209

Induction Heating Stress Improvement Effectiveness on Crack Growth in Operating Plants (BWRVIP-61)  

Science Conference Proceedings (OSTI)

New reports of intergranular stress corrosion cracking prompted this review of factors that could influence the performance of the pipe cracking remedy known as induction heating stress improvement.

1999-01-27T23:59:59.000Z

210

Health, Wartime Stress, and Unit Cohesion: Evidence from Union Army Veterans  

E-Print Network (OSTI)

Health, Wartime, Stress, and Unit Cohesion: Evidence fromHealth, Wartime Stress, and Unit Cohesion: Evidence fromhow the interaction between unit cohesiveness and combat

Costa, Dora L.; Kahn, Matthew E.

2008-01-01T23:59:59.000Z

211

A thin-plate analysis and experimental evaluation of couple-stress ...  

Science Conference Proceedings (OSTI)

annealed and wrought conditions in order to establish the order of magnitude of the couple stress constant l as found in a simple couple-stress theory. Results ...

212

Over Core Stress At Gabbs Valley Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

Over Core Stress At Gabbs Valley Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Over Core Stress At Gabbs Valley Area (DOE GTP)...

213

Surveillance Guide - OSS 19.8 Heat Stress  

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

HEAT STRESS HEAT STRESS 1.0 Objective The objective of this surveillance is to evaluate the effectiveness of actions taken by the contractor to protect workers from the effects of heat stress. The Facility Representative will observe work where heat stress is a risk and examine implementation of applicable administrative controls. The surveillance provides a basis for evaluating compliance with applicable DOE requirements and implementation of best industry practices. 2.0 References 2.1 DOE 5480.4, Environmental Protection, Safety and Health Protection Standards 2.2 DOE 5483.1A, Occupational Safety and Health Program for DOE Contractor Employees at Government-Owned Contractor- Operated Facilities 2.3 U.S. Environmental Protection Agency, Publication

214

Propeller blade stress estimates using lifting line theory  

E-Print Network (OSTI)

OpenProp, an open-source computational tool for the design and analysis of propellers and horizontal-axis turbines, is extended to provide estimates of normal stresses in the blades for both on- and off-design operating ...

Epps, Brenden P.

215

Detailed stress tensor measurements in a centrifugal compressor vaneless diffuser  

Science Conference Proceedings (OSTI)

Detailed flow measurements have been made in the vaneless diffuser of a large low-speed centrifugal compressor using hot-wire anemometry. The three time mean velocity components and full stress tensor distributions have been determined on eight measurement plans within the diffuser. High levels of Reynolds stress result in the rapid mixing out of the blade wake. Although high levels of turbulent kinetic energy are found in the passage wake, they are not associated with strong Reynolds stresses and hence the passage wake mixes out only slowly. Low-frequency meandering of the wake position is therefore likely to be responsible for the high kinetic energy levels. The anisotropic nature of the turbulence suggests that Reynolds stress turbulence models are required for CFD modeling of diffuser flows.

Pinarbasi, A.; Johnson, M.W. [Univ. of Liverpool (United Kingdom). Dept. of Mechanical Engineering

1996-04-01T23:59:59.000Z

216

Wind Stress Drag Coefficient over the Global Ocean  

Science Conference Proceedings (OSTI)

Interannual and climatological variations of wind stress drag coefficient (CD) are examined over the global ocean from 1998 to 2004. Here CD is calculated using high temporal resolution (3- and 6-hourly) surface atmospheric variables from two ...

A. Birol Kara; Alan J. Wallcraft; E. Joseph Metzger; Harley E. Hurlburt; Chris W. Fairall

2007-12-01T23:59:59.000Z

217

Modeling and Optimizing the Thermal Stress Distribution in a ...  

Science Conference Proceedings (OSTI)

Conference Tools for Materials Science & Technology 2012 ... Presentation Title, Modeling and Optimizing the Thermal Stress Distribution in a Plasma Spray System for ... and analyzed for an applied thermal load in COMSOL® Multiphysics®.

218

Evaluation of Stress Corrosion Cracking Susceptibility of Drill Pipe ...  

Science Conference Proceedings (OSTI)

G-105 and S-135 grades of drill pipe steels have been used to study the effect of temperature and solution chemistry on the stress corrosion cracking behavior of ...

219

Ambient Temperature Stress Corrosion Cracking of 304L Stainless ...  

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 ...

220

Anisotropic stress and stability in modified gravity models  

Science Conference Proceedings (OSTI)

The existence of anisotropic stress of a purely geometrical origin seems to be a characteristic of higher order gravity models, and has been suggested as a probe to test these models observationally, for example, in weak lensing experiments. In this paper, we seek to find a class of higher order gravity models of f(R,G) type that would give us a zero anisotropic stress and study the consequences for the viability of the actual model. For the special case of a de Sitter background, we identify a subclass of models with the desired property. We also find a direct link between anisotropic stress and the stability of the model as well as the presence of extra degrees of freedom, which seems to be a general feature of higher order gravity models. Particularly, setting the anisotropic stress equal to zero for a de Sitter background leads to a singularity that makes it impossible to reach the de Sitter evolution.

Saltas, Ippocratis D. [Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom); Kunz, Martin [Departement de Physique Theorique, Universite de Geneve, 1211 Geneva 4 (Switzerland)

2011-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Continental Shelf Circulation Induced by a Moving, Localized Wind Stress  

Science Conference Proceedings (OSTI)

A linear, two-dimensional model of a rotating, stratified fluid is constructed to investigate the circulation induced by a moving, localized line of surface stress. This model is used to analyze the effect of moving cold fronts on continental ...

John M. Klinck; Leonard J. Pietrafesa; Gerald S. Janowitz

1981-06-01T23:59:59.000Z

222

Stress Wave Source Characterization: Impact, Fracture, and Sliding Friction  

E-Print Network (OSTI)

stress wave sources from the PMMA and rock are then linkedof a 3-D source inside an artificial rock, J. Sound Vib.two different calibration sources on the rock base plate. a,

McLaskey, Gregory Christofer

2011-01-01T23:59:59.000Z

223

Stress Relief Treatment of Alloy 600 Steam Generator Tubing  

Science Conference Proceedings (OSTI)

Various time-temperature combinations may hold potential for improving the resistance of tubesheet transition regions to intergranular stress corrosion cracking (IGSCC). EPRI has discovered that the most significant enhancement in IGSCC of Alloy 600 steam generator tubing occurs with stress relief heat treatments administered in the range of 550-610 degrees Celsius for an average of nine hours. Treatments administered for shorter times at temperatures greater than 700 degrees Celsius also proved effective.

1994-03-05T23:59:59.000Z

224

Nondestructive Evaluation: Nondestructive Evaluation and Measurement of Residual Stress  

Science Conference Proceedings (OSTI)

This report summarizes the results of nondestructive evaluation (NDE) techniques for residual stress measurements conducted on Alloy 600 samples that have undergone changes in material properties resulting from simulated operating conditions, including heat treatment, three-point bending load, cracking, and repair. The overall objective was to identify suitable NDE techniques that would augment the existing and proven surface residual stress measurements by X-ray diffraction (XRD) and extend the measurem...

2009-12-01T23:59:59.000Z

225

SURVEY AND SUMMARY RNA helicases and abiotic stress  

E-Print Network (OSTI)

RNA helicases function as molecular motors that rearrange RNA secondary structure, potentially performing roles in any cellular process involving RNA metabolism. Although RNA helicase association with a range of cellular functions is well documented, their importance in response to abiotic stress is only beginning to emerge. This review summarizes the available data on the expression, biochemistry and physiological function(s) of RNA helicases regulated by abiotic stress. Examples originate primarily from non-mammalian organisms while instances from mammalian sources are restricted to post-translational regulation of helicase biochemical activity. Common emerging themes include the requirement of a cold-induced helicase in non-homeothermic organisms, association and regulation of helicase activity by stress-induced phosphorylation cascades, altered nuclear– cytoplasmic shuttling in eukaryotes, association with the transcriptional apparatus and the diversity of biochemical activities catalyzed by a subgroup of stress-induced helicases. The data are placed in the context of a mechanism for RNA helicase involvement in cellular response to abiotic stress. It is proposed that stress-regulated helicases can catalyze a nonlinear, reversible sequence of RNA secondary structure rearrangements which function in RNA maturation or RNA proofreading, providing a mechanism by which helicase activity alters the activation state of target RNAs through regulation of the reaction equilibrium.

George W. Owttrim

2006-01-01T23:59:59.000Z

226

Uncertainty in the maximum principal stress estimated from hydraulic fracturing Measurements due to the presence of the induced fracture  

E-Print Network (OSTI)

Laboratory study of hydraulic fracturing pressure data?Howevaluation of hydraulic fracturing stress measurementreopening during hydraulic fracturing stress determinations.

Rutqvist, Jonny; Tsang, Chin-fu; Stephansson, Ove

2000-01-01T23:59:59.000Z

227

Materials Reliability Program: Technical Basis for Primary Water Stress Corrosion Cracking Mitigation by Surface Stress Improvement (MRP-267, Revision 1)  

Science Conference Proceedings (OSTI)

During the past two decades, stress corrosion cracking (SCC) has become the most relevant phenomenon affecting nuclear plant availability and plant lifetime management. SCC can lead to increased costs for operation, maintenance, assessment, repair, and replacement of boiling water reactor (BWR) and pressurized water reactor (PWR) components. Alloy 600 and 82/182 materials, which are widely used in PWR systems, are susceptible to primary water stress corrosion cracking (PWSCC). PWSCC has been reported in ...

2012-07-31T23:59:59.000Z

228

Prediction and verification of microRNAs related to proline accumulation under drought stress in potato  

Science Conference Proceedings (OSTI)

Proline is an important osmotic adjusting material greatly accumulated under drought stress and can help plant to adapt to osmotic stress. MicroRNAs (miRNAs) are small, endogenous RNAs that play important regulatory roles in plant development and stress ... Keywords: Computer prediction, Drought stress, MircoRNA, Potato, Proline accumulation

Jiangwei Yang, Ning Zhang, Congyu Ma, Yun Qu, Huaijun Si, Di Wang

2013-10-01T23:59:59.000Z

229

AN ANALYSIS OF THE MEASURED VALUES FOR THE STATE OF STRESS IN THE EARTH'S CRUST  

E-Print Network (OSTI)

Jung, R. (1975). Hydraulic Fracturing Stress Measurements,measurement in hydraulic fracturing has been described by

Jamison, Dennis B.; Cook, Neville G.W.

2008-01-01T23:59:59.000Z

230

AN ANALYSIS OF THE MEASURED VALUES FOR THE STATE OF STRESS IN THE EARTH'S CRUST  

E-Print Network (OSTI)

Jung, R. (1975). Hydraulic Fracturing Stress Measurements,measurement in hydraulic fracturing has been described by

Cook, Neville G.W.

2010-01-01T23:59:59.000Z

231

The importance of in-situ-stress profiles in hydraulic-fracturing applications  

Science Conference Proceedings (OSTI)

In-situ stresses define the local forces acting on lithologic layers in the subsurface. Knowledge of these stresses is important in drilling, wellbore-stability, and, especially, hydraulic-fracturing applications. The measurement of in-situ stress is not straightforward and, therefore, often goes unmeasured. As such, one often assumes values of in-situ stress or estimate in-situ stresses from logging parameters. This article illustrates the importance of in-situ-stress estimates as they relate to hydraulic fracturing and outlines several techniques for estimating in-situ-stress magnitudes.

Hopkins, C.W. [S.A. Holditch and Associates, Inc., Houston, TX (United States). Houston Div.

1997-09-01T23:59:59.000Z

232

Wall Orientation and Shear Stress in the Lattice Boltzmann Model  

E-Print Network (OSTI)

The wall shear stress is a quantity of profound importance for clinical diagnosis of artery diseases. The lattice Boltzmann is an easily parallelizable numerical method of solving the flow problems, but it suffers from errors of the velocity field near the boundaries which leads to errors in the wall shear stress and normal vectors computed from the velocity. In this work we present a simple formula to calculate the wall shear stress in the lattice Boltzmann model and propose to compute wall normals, which are necessary to compute the wall shear stress, by taking the weighted mean over boundary facets lying in a vicinity of a wall element. We carry out several tests and observe an increase of accuracy of computed normal vectors over other methods in two and three dimensions. Using the scheme we compute the wall shear stress in an inclined and bent channel fluid flow and show a minor influence of the normal on the numerical error, implying that that the main error arises due to a corrupted velocity field near ...

Matyka, Maciej; Miros?aw, ?ukasz

2013-01-01T23:59:59.000Z

233

Measuring residual stress in glasses and ceramics using instrumented indentation.  

Science Conference Proceedings (OSTI)

Instrumented indentation has yielded mixed results when used to measure surface residual stresses in metal films. Relative to metals, many glasses and ceramics have a low modulus-to-yield strength (E/sy) ratio. The advantage of this characteristic for measuring residual stress using instrumented indentation is demonstrated by a series of comparative spherical and conical tip finite element simulations. Two cases are considered: (i) a material with E/s{sub y} = 24-similar to glass and (ii) a material with E/s{sub y} = 120-similar to metal films. In both cases, compressive residual stress shifts the simulated load-displacement response toward increasing hardness, irrespective of tip geometry. This shift is shown to be entirely due to pile up for the ''metal'' case, but primarily due to the direct influence of the residual stress for the ''glass'' case. Hardness changes and load-displacement curve shifts are explained by using the spherical cavity model. Supporting experimental results on stressed glasses are provided.

Tandon, Rajan; Buchheit, Thomas E.

2007-03-01T23:59:59.000Z

234

Researchers Devise New Stress Test for Irradiated Materials | Department of  

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

Researchers Devise New Stress Test for Irradiated Materials Researchers Devise New Stress Test for Irradiated Materials Researchers Devise New Stress Test for Irradiated Materials July 20, 2011 - 3:58pm Addthis Scientists conducted compression tests of copper specimens irradiated with high-energy protons, designed to model how damage from radiation affects the mechanical properties of copper. By using a specialized in situ mechanical testing device in a transmission electron microscope at the National Center for Electron Microscopy, the team could examine — with nanoscale resolution — the localized nature of this deformation. | Courtesy of Lawrence Berkeley National Laboratory Scientists conducted compression tests of copper specimens irradiated with high-energy protons, designed to model how damage from radiation affects

235

Spray Shadowing For Stress Relief And Mechanical Locking In Thick  

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

Advanced Materials » Advanced Materials » Spray Shadowing For Stress Relief And Mechanical Locking Spray Shadowing For Stress Relief And Mechanical Locking In Thick Protective Coatings A method for applying a protective coating on an article. Available for thumbnail of Feynman Center (505) 665-9090 Email Spray Shadowing For Stress Relief And Mechanical Locking In Thick Protective Coatings A method for applying a protective coating on an article, comprising the following steps: selecting an article with a surface for applying a coating thickness; creating undercut grooves on the article, where the grooves depend beneath the surface to a bottom portion with the grooves having an upper width on the surface and a lower width on the bottom portion connected by side walls, where at least one of the side walls connects the

236

Develop baseline computational model for proactive welding stress  

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

Develop baseline computational model for proactive welding stress Develop baseline computational model for proactive welding stress management to suppress helium induced cracking during weld repair Develop baseline computational model for proactive welding stress management to suppress helium induced cracking during weld repair There are over 100 nuclear power plants operating in the U.S., which generate approximately 20% of the nation's electricity. These plants range from 15 to 40 years old. Extending the service lives of the current fleet of nuclear power plants beyond 60 years is imperative to allow for the environmentally-sustainable energy infrastructure being developed and matured. Welding repair of irradiated nuclear reactor materials (such as austenitic stainless steels) is especially challenging because of the

237

Researchers Devise New Stress Test for Irradiated Materials | Department of  

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

Researchers Devise New Stress Test for Irradiated Materials Researchers Devise New Stress Test for Irradiated Materials Researchers Devise New Stress Test for Irradiated Materials July 20, 2011 - 3:58pm Addthis Scientists conducted compression tests of copper specimens irradiated with high-energy protons, designed to model how damage from radiation affects the mechanical properties of copper. By using a specialized in situ mechanical testing device in a transmission electron microscope at the National Center for Electron Microscopy, the team could examine — with nanoscale resolution — the localized nature of this deformation. | Courtesy of Lawrence Berkeley National Laboratory Scientists conducted compression tests of copper specimens irradiated with high-energy protons, designed to model how damage from radiation affects

238

Computational Core | VIMSS - Virtual Institute for Microbial Stress and  

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

Cloning of Identified Pathways Cloning of Identified Pathways Functional Genomics The goal of the Functional Genomics Core is to develop the experimental methods to elucidate the regulatory networks in the stress responses of Desulfovibrio vulgaris, Shewanella oneidensi, and Geobacter metallireducens. Specifically, we propose to: use existing DNA arrays for S. oneidensis, and to develop DNA arrays for D. vulgaris and G. metallireducens to measure the transcript profile (transcriptome) during the response to various environmental stresses; use HPLC-MS-MS to measure the protein profile (proteome) of D. vulgaris, G. metallireducens, and S. oneidensis during the response to various environmental stresses; measure the metabolite profile (metabolome) of D. vulgaris, G. metallireducens, and S. oneidensis during the response to various

239

VIMSS - Virtual Institute for Microbial Stress and Survival  

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

featuredproject ESPP222 Environmental Stress Pathway Project (ESPP2) formerly known as Rapid Deduction of Stress Response Pathways in Metal/Radionuclide Reducing Bacteria Adam Arkin, co-Principal Investigator (LBNL, Physical Biosciences Division) and Terry Hazen, co-Principal Investigator (LBNL, Earth Sciences Division) ESPP2 is developing computational models that describe and predict the behavior of gene regulatory networks in microbes in response to the environmental conditions found in DOE waste sites. The research takes place within the Virtual Institute for Microbial Stress and Survival (VIMSS). >> More about ESPP2 >> View all projects featured project desufovibrio microbesonline.com MicrobesOnline is designed specifically to facilitate comparative studies on prokaryotic genomes.

240

Memory Testing Under Different Stress Conditions: An Industrial Evaluation  

E-Print Network (OSTI)

This paper presents the effectiveness of various stress conditions (mainly voltage and frequency) on detecting the resistive shorts and open defects in deep sub-micron embedded memories in an industrial environment. Simulation studies on very-low voltage, high voltage and at-speed testing show the need of the stress conditions for high quality products; i.e., low defect-per-million (DPM) level, which is driving the semiconductor market today. The above test conditions have been validated to screen out bad devices on real silicon (a test-chip) built on CMOS 0.18 um technology. IFA (inductive fault analysis) based simulation technique leads to an efficient fault coverage and DPM estimator, which helps the customers upfront to make decisions on test algorithm implementations under different stress conditions in order to reduce the number of test escapes.

Majhi, Ananta K; Gronthoud, Guido; Lousberg, Maurice; Eichenberger, Stefan; Bowen, Fred

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Stress versus temperature dependent activation energies in creep  

SciTech Connect

The activation energy for creep at low stresses and elevated temperatures is lattice diffusion, where the rate controlling mechanism for deformation is dislocation climb. At higher stresses and intermediate temperatures, the rate controlling mechanism changes from that of dislocation climb to one of obstacle-controlled dislocation glide. Along with this change, there occurs a change in the activation energy. It is shown that a temperature-dependent Gibbs free energy does a good job of correlating steady-state creep data, while a stress-dependent Gibbs free energy does a less desirable job of correlating the same data. Applications are made to copper and a LiF-22 mol. percent CaF2 hypereutectic salt.

Freed, A.D.; Raj, S.V.; Walker, K.P.

1990-01-01T23:59:59.000Z

242

Investigation of Stress Indices and Directional Loading of Eccentric Reducers  

SciTech Connect

OAK- B135 Engineering for fatigue is an essential concern in piping systems. Addressing this concern, the ASME Section III and ANSI B31.1 Codes provide stress indices and stress intensification factors (SIFs) to be used in the design and evaluation of Class 1, 2 and 3 systems. In recent research cosponsored by EPRI and the U.S. DOE, new test data have been developed for comparison with the ASME stress indices and SIFs. This report presents the results of fatigue tests on eccentric reducers, taking into account the directionality of the loading. As detailed in the report, the results can help to improve the evaluation of reducers and can help to reduce unnecessary conservatism in piping system design.

R. Carter,E.A. Wais, E.C. Rodabaugh

2003-08-01T23:59:59.000Z

243

Ralf Weisse and Hans von Storch, Helmholtz-Zentrum Geesthacht, Institute for Coastal Research, Contact: ralf.weisse@hzg.de Helmholtz-Zentrum Geesthacht Max-Planck-Strae 1 21502 Geesthacht Phone +49 (0)4152 87-2819 Fax +49 (0)4152 87-2818 www.hzg.de  

E-Print Network (OSTI)

of installation of offshore wind farms (from Wiese 2008: Auswirkungen der Offshore-Windenergie auf den Betrieb von and offshore applications require appropriate planning and design. For most of them, statistics of extreme wind coastDat have been used in a large variety of coastal, offshore and terrestrial applications

von Storch, Hans

244

Physics-Based Stress Corrosion Cracking Component Reliability  

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

Physics-Based Stress Corrosion Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage Framework Draft Report Supporting Technology Inputs to the Risk- Informed Safety Margin Characterization Pathway of the DOE Light Water Reactor Sustainability Program Stephen D. Unwin Kenneth I. Johnson Robert F. Layton Peter P. Lowry Scott E. Sanborn Mychailo B. Toloczko PNNL-20596 July 2011 Physics-Based SCC Reliability Model in a Cumulative Damage Framework 2 Physics-Based SCC Reliability Model in a Cumulative Damage Framework 3 Table of Contents Executive Summary............................................................................... 4 1. Introduction .......................................................................... 5

245

Triple-material stress-strain resistivity gage  

DOE Patents (OSTI)

A triple material piezoresistive gage provides multi-component elastic stress or strain measurements. Thin foils of three piezoresistive materials, e.g., ytterbium, manganin, and constantan, are configured in a nested serpentine rectilinear grind or other grind arrangement and embedded in a medium, preferably normal to the direction of shock wave propagation. The output of the gage is a resistivity change history for each material of gage. Each resistivity change is independent of the others so that three diagonal components of the elastic stress or strain tensor can be calculated form the resistivity measurements. 4 figs.

Stout, R.B.

1987-05-19T23:59:59.000Z

246

Triple-material stress-strain resistivity gage  

DOE Patents (OSTI)

A triple material piezoresistive gage provides multi-component elastic stress measurements is disclosed. Thin foils of three piezoresistive materials, e.g. ytterbium, manganin, and constantan, are configured in a nested serpentine rectilinear grid or other grid arrangement and embedded in a medium, preferably normal to the direction of shock wave propagation. The output of the gage is a resistivity change history for each material of the gage. Each resistivity change is independent of the others so that three diagonal components of the elastic stress or strain tensor can be calculated from the resistivity measurements. 4 figs.

Stout, R.B.

1988-05-17T23:59:59.000Z

247

Triple-material stress-strain resistivity gage  

DOE Patents (OSTI)

A triple material piezoresistive gage provides multi-component elastic stress or measurements. Thin foils of three piezoresistive materials, e.g. ytterbium, manganin, and constantan, are configured in a nested serpentine rectilinear grid or other grid arrangement and embedded in a medium, preferably normal to the direction of shock wave propagation. The output of the gage is a resistivity change history for each material of the gage. Each resistivity change is independent of the others so that three diagonal components of the elastic stress or strain tensor can be calculated from the resistivity measurements.

Stout, Ray B. (Livermore, CA)

1988-01-01T23:59:59.000Z

248

Hydrogen sulfide stress corrosion cracking in materials for geothermal power  

DOE Green Energy (OSTI)

Studies to evaluate the performance of alloys used in geothermal power systems are reported. Alloys which are commercially available and those which have modified metallurgical structures and/or composition modifications were tested to determine the corrosive effects of the H/sub 2/S and thermal environments in geothermal fluids. Hydrogen embrittlement and sulfide stress corrosion cracking were tested. Test results showing the effects of alloy composition, tempering temperatures, fluid temperature and salt content, and ageing on sulfide stress cracking are tabulated. (LCL)

Hehemann, R.F.; Troiano, A.R.; Abu-Khater, B.; Ferrigno, S.

1976-01-01T23:59:59.000Z

249

Time and Space Variability of Tropical Pacific Wind Stress  

Science Conference Proceedings (OSTI)

The results of a spectral analysis of a new, subjectively analyzed data set of tropical Pacific wind stress are presented. The monthly data for the 10-year period, 1961–70, allow a detailed inspection of the distributions of frequency and zonal ...

Stanley B. Goldenberg; James J. O'Brien

1981-06-01T23:59:59.000Z

250

Raman study of lead zirconate titanate under uniaxial stress  

SciTech Connect

The authors used micro-Raman spectroscopy to monitor the ferroelectric (FE) to antiferroelectric (AFE) phase transition in PZT ceramic bars during the application of uniaxial stress. They designed and constructed a simple loading device, which can apply sufficient uniaxial force to transform reasonably large ceramic bars while being small enough to fit on the mechanical stage of the microscope used for Raman analysis. Raman spectra of individual grains in ceramic PZT bars were obtained as the stress on the bar was increased in increments. At the same time gauges attached to the PZT bar recorded axial and lateral strains induced by the applied stress. The Raman spectra were used to calculate an FE coordinate, which is related to the fraction of FE phase present. The authors present data showing changes in the FE coordinates of individual PZT grains and correlate these changes to stress-strain data, which plot the macroscopic evolution of the FE-to-AFE transformation. Their data indicates that the FE-to-AFE transformation does not occur simultaneously for all PZT grains but that grains react individually to local conditions.

TALLANT, DAVID R.; SIMPSON, REGINA L.; GRAZIER, J. MARK; ZEUCH, DAVID H.; OLSON, WALTER R.; TUTTLE, BRUCE A.

2000-04-01T23:59:59.000Z

251

Zymomonas with improved xylose utilization in stress conditions  

DOE Patents (OSTI)

Strains of xylose utilizing Zymomonas with improved xylose utilization and ethanol production during fermentation in stress conditions were obtained using an adaptation method. The adaptation involved continuously growing xylose utilizing Zymomonas in media containing high sugars, acetic acid, ammonia, and ethanol.

Caimi, Perry G; Emptage, Mark; Li, Xu; Viitanen, Paul V; Chou, Yat-Chen; Franden, Mary Ann; Zhang, Min

2013-06-18T23:59:59.000Z

252

Wind Stress from Wave Slopes Using Phillips Equilibrium Theory  

Science Conference Proceedings (OSTI)

An open ocean, deep water air–sea interaction experiment was conducted in the Gulf of Alaska. Wave amplitude and slope data were measured using a WAVEC heave, pitch, and roll buoy that was let drift in the Alaska gyre. Wind stress estimates were ...

Barbara-Ann Juszko; Richard F. Marsden; Sherman R. Waddell

1995-02-01T23:59:59.000Z

253

Role of Slip Behavior in the Irradiation Assisted Stress Corrosion ...  

Science Conference Proceedings (OSTI)

Crack Growth Rates of Irradiated Commercial Stainless Steels in BWR and PWR ... Detailed Root Cause Analysis of SG Tube ODSCC Indications within the Tube Sheets of NPP Biblis Unit A .... Radiation Damage in Fe-C-Met Model Alloys ... Stress Corrosion Cracking Behavior near the Fusion Boundary of Dissimilar Weld

254

Penetrative Internal Oxidation from Alloy 690 Surfaces and Stress ...  

Science Conference Proceedings (OSTI)

Crack Growth Rates of Irradiated Commercial Stainless Steels in BWR and PWR ... Detailed Root Cause Analysis of SG Tube ODSCC Indications within the Tube Sheets of NPP Biblis Unit A .... Radiation Damage in Fe-C-Met Model Alloys ... Stress Corrosion Cracking Behavior near the Fusion Boundary of Dissimilar Weld

255

Wave Dependence of Sea-Surface Wind Stress  

Science Conference Proceedings (OSTI)

Distribution of the wind stress over the oceans is usually estimated by using a bulk formula. It contains the squared 10-m wind speed multiplied by the drag coefficient, which has been assumed in many cases to be a weak function of the 10-m wind ...

Yoshiaki Toba; Noriko Iida; Hiroshi Kawamura; Naoto Ebuchi; Ian S. F. Jones

1990-05-01T23:59:59.000Z

256

Velocity and Stress in the Deep-Ocean Boundary Layer  

Science Conference Proceedings (OSTI)

In order to predict the response of deep ocean sediments to the near-bottom currents, accurate estimates of the near-bottom velocity and the boundary shear stress are necessary. Because of the unsteady nature of deep ocean currents, dynamic ...

S. R. McLean; J. Yean

1987-09-01T23:59:59.000Z

257

A von Hamos x-ray spectrometer based on a segmented-type diffraction crystal for single-shot x-ray emission spectroscopy and time-resolved resonant inelastic x-ray scattering studies  

SciTech Connect

We report on the design and performance of a wavelength-dispersive type spectrometer based on the von Hamos geometry. The spectrometer is equipped with a segmented-type crystal for x-ray diffraction and provides an energy resolution in the order of 0.25 eV and 1 eV over an energy range of 8000 eV-9600 eV. The use of a segmented crystal results in a simple and straightforward crystal preparation that allows to preserve the spectrometer resolution and spectrometer efficiency. Application of the spectrometer for time-resolved resonant inelastic x-ray scattering and single-shot x-ray emission spectroscopy is demonstrated.

Szlachetko, J. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Nachtegaal, M.; Boni, E. de; Willimann, M.; Safonova, O.; Sa, J.; Smolentsev, G.; Szlachetko, M.; Bergamaschi, A.; Schmitt, B.; David, C.; Luecke, A. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Bokhoven, J. A. van [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Institute for Chemical and Bioengineering, ETH Zurich, 8093 Zuerich (Switzerland); Dousse, J.-Cl.; Hoszowska, J.; Kayser, Y. [Department of Physics, University of Fribourg, 1700 Fribourg (Switzerland); Jagodzinski, P. [University of Technology, Kielce (Poland)

2012-10-15T23:59:59.000Z

258

Influence of electrode stress on proton exchange membrane fuel cell performance : experimental characterization and power optimization  

E-Print Network (OSTI)

Compressive stress applied to the electrode area of a Proton Exchange Membrane (PEM) fuel cell is known to significantly affect power output. In practice, electrode stress arises during operation due to the clamping force ...

Gallant, Betar M. (Betar Maurkah)

2008-01-01T23:59:59.000Z

259

Thermal stress cracking and enhancement of heat extraction from fractured geothermal reservoirs  

DOE Green Energy (OSTI)

The effects of thermal stress cracking, upon heat extraction were studied. Very fundamental approximate analyses were performed to elucidate the mechanics of thermal stress cracking, and the main results are summarized.

Murphy, H.D.

1978-01-01T23:59:59.000Z

260

Y8, Stress Mapping Analysis by Ray Tracing (SMART): A New ...  

Science Conference Proceedings (OSTI)

A fine grid made out of X-ray absorbing material is placed in the path of ... Stress Mapping Analysis by Ray Tracing (SMART), to fully determine the state of stress ...

Note: This page contains sample records for the topic "von mises stress" 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

On the Forcing Mechanisms Affecting the Bottom Shear Stress in Coastal Waters  

Science Conference Proceedings (OSTI)

Three papers have appeared in the literature in the past four years which report current data indicating that the bottom shear stress is larger than the surface shear stress. The sites involved in the three studies had many similarities including ...

Cortis Cooper; Bryan Pearce

1980-11-01T23:59:59.000Z

262

Direct Estimation of the Reynolds Stress Vertical Structure in the Nearshore  

Science Conference Proceedings (OSTI)

Measurements of the vertical Reynolds stress components in the wave-dominated nearshore are required to diagnose momentum and turbulence dynamics. Removing wave bias from Reynolds stress estimates is critical to a successful diagnosis. Here two ...

Falk Feddersen; A. J. Williams III

2007-01-01T23:59:59.000Z

263

The Role of Terrain and Pressure Stresses in Rocky Mountain Lee Cyclones  

Science Conference Proceedings (OSTI)

The earth–atmosphere exchange of storm absolute dynamic circulation by mountain-induced surface pressure stress and the response of the circulation in a Rocky Mountain Ice cyclone is examined. Surface pressure stresses that transfer horizontal ...

Alan C. Czarnetzki; Donald R. Johnson

1996-04-01T23:59:59.000Z

264

An Overview of Stress Cracking of Pipeline Steels in Near-neutral ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Stress cracking of pipeline steels in near-neutral pH has remained a virile integrity risk for oil and gas pipelines. Although it was termed as stress ...

265

Step-Stress Accelerated Degradation Testing (SSADT) for Photovoltaic (PV) Devices and Cells (Presentation)  

DOE Green Energy (OSTI)

Presentation on step-stress accelerated degradation testing (SSADT) for photovoltaics (PV). Developed are a step-stress degradation test (SSADT) for PV reliability tests and a lifetime prediction model for PV products.

Lee, J.; Elmore, R.; Suh, C.; Jones, W.

2010-10-01T23:59:59.000Z

266

Modeling the relation between suction, effective stress and shear strength in partially saturated granular media  

E-Print Network (OSTI)

Decades of geotechnical research firmly established that the mechanical properties (shear strength and deformation characteristics) of soils are related to soil's "effective stress", i.e. the stress carried by the solid ...

Toker, Nabi Kartal, 1979-

2007-01-01T23:59:59.000Z

267

Comparison of In-Reactor Creep and Stress Relaxation of Cold ...  

Science Conference Proceedings (OSTI)

The results show that in-reactor creep and stress relaxation are different in fast ... Applicability of Lean Grade of Duplex Stainless Steels in Nuclear Power Plants .... Stress Corrosion Cracking Behavior near the Fusion Boundary of Dissimilar ...

268

Stability Parameters and Wind-Stress Coefficients under Various Atmospheric Conditions  

Science Conference Proceedings (OSTI)

Stability parameters and wind-stress coefficients under various atmospheric conditions are related to wind velocity and air-sea temperature difference. Readily applicable formulae, without iterative computations, of wind-stress coefficients under ...

Jin Wu

1986-06-01T23:59:59.000Z

269

The Development of a Warm-Weather Relative Stress Index for Environmental Applications  

Science Conference Proceedings (OSTI)

The heat stress index (HSI) is a new, comprehensive summer index that evaluates daily relative stress for locations throughout the United States based on deviations from the norm. The index is based on apparent temperature and other derived ...

Jill D. Watts; Laurence S. Kalkstein

2004-04-01T23:59:59.000Z

270

Change of Stress-Strain Behaviors in EB-PVD TBC Coating Systems ...  

Science Conference Proceedings (OSTI)

... coating system, axial stress born by applied external condition changes from compression to tension. ... Aerospace Coatings via Directed Vapor Deposition.

271

A model for residual stress evolution in air-plasma-sprayed zirconia thermal barrier coatings  

Science Conference Proceedings (OSTI)

Ruby fluorescence spectroscopy indicates that residual stress in air-plasma-sprayed zirconia thermal barrier coatings is a function of the local interface geometry. The stress profile of a simulated rough interface characterized by ``peaks'' and ``valleys'' was modeled with a finite-element approach that accounted for thermal mismatch, oxide scale growth, and top coat sintering. Dependence of the stress profile on interface geometry and microstructure was investigated, and the results were compared with measured stresses.

Nair, B. G.; Singh, J. P.; Grimsditch, M.

2000-02-28T23:59:59.000Z

272

X-ray diffraction study of residual stress in model weldments. Final report  

Science Conference Proceedings (OSTI)

Residual stress in a model weldment in nickel plate was characterized using x-ray diffraction techniques. The stress was mapped in 2 mm divisions up to the boundary of the weld pool. Results were in generally good agreement with the stress levels previously predicted for this system by finite element studies at LLNL. Recommendations are made that would permit 1 mm/sup 2/ spatial resolution maps of residual stress in stainless steel weldments.

Stroud, R.D.; Shackelford, J.F.

1980-11-01T23:59:59.000Z

273

Root-Water-Uptake Based upon a New Water Stress Reduction and an Asymptotic Root Distribution Function  

Science Conference Proceedings (OSTI)

A water stress–compensating root-water-uptake module was developed based upon a newly proposed water stress reduction function and an asymptotic root distribution function. The water stress reduction function takes into account both soil water ...

K. Y. Li; R. De Jong; M. T. Coe; N. Ramankutty

2006-06-01T23:59:59.000Z

274

Elastic incompatibility stresses across planar and nonplanar grain boundaries in silver, aluminum, and zirconium applied to ductile fracture criteria under high triaxial stress  

Science Conference Proceedings (OSTI)

Grain boundaries in a polycrystal imply elastic incompatibilities that can lead to stress states in the vicinity of the interface that are different from the macroscopic or applied stresses because the single crystal elastic properties are not all isotropic. This phenomenon is important as mechanical processes may operate at the microscopic level that would not be predicted based on the macroscopic stress state. This phenomenon has not been widely examined. One of the few studies that examined the level of stress- state modification on copper determined that slip or plasticity in cyclically deformed copper occurred in areas with high elastic incompatibility stresses. The focus of the present study is the unstable growth of cavities as a result of high local triaxial stress. Grain boundaries in silver, aluminum, and zirconium are examined.

Roehnelt, R.; Kassner, M.E.; Kennedy, T.C. [Oregon State Univ., Corvallis, OR (United States); Rosen, R.S. [Lawrence Livermore National Lab., CA (United States)

1996-07-01T23:59:59.000Z

275

2010 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 18-23, 2010  

SciTech Connect

The 2010 Gordon Research Conference on Microbial Stress Responses provides an open and exciting forum for the exchange of scientific discoveries on the remarkable mechanisms used by microbes to survive in nearly every niche on the planet. Understanding these stress responses is critical for our ability to control microbial survival, whether in the context of biotechnology, ecology, or pathogenesis. From its inception in 1994, this conference has traditionally employed a very broad definition of stress in microbial systems. Sessions will cover the major steps of stress responses from signal sensing to transcriptional regulation to the effectors that mediate responses. A wide range of stresses will be represented. Some examples include (but are not limited to) oxidative stress, protein quality control, antibiotic-induced stress and survival, envelope stress, DNA damage, and nutritional stress. The 2010 meeting will also focus on the role of stress responses in microbial communities, applied and environmental microbiology, and microbial development. This conference brings together researchers from both the biological and physical sciences investigating stress responses in medically- and environmentally relevant microbes, as well as model organisms, using cutting-edge techniques. Computational, systems-level, and biophysical approaches to exploring stress responsive circuits will be integrated throughout the sessions alongside the more traditional molecular, physiological, and genetic approaches. The broad range of excellent speakers and topics, together with the intimate and pleasant setting at Mount Holyoke College, provide a fertile ground for the exchange of new ideas and approaches.

Sarah Ades

2011-07-23T23:59:59.000Z

276

Modelling stress reduction techniques of cold compression and stretching in wrought Aluminium alloy products  

Science Conference Proceedings (OSTI)

Heat treatable aluminium alloy aerospace products undergo a rapid quench from the solution heat treatment temperature into water/organic quenchant/spray quenching system during processing. As a result of this rapid quenching operation, residual stresses ... Keywords: aluminium alloy 7010, aluminium alloy forgings, cold compression, quenching stresses, residual stress

D. A. Tanner; J. S. Robinson

2003-03-01T23:59:59.000Z

277

Early Development Of Stress Corrosion Cracks At The Grain Scale: Incomplete Random Tessellation Model  

E-Print Network (OSTI)

Early Development Of Stress Corrosion Cracks At The Grain Scale: Incomplete Random Tessellation is needed to quantify those effects more accurately. 1 INTRODUCTION Intergranular stress corrosion cracking to the dependence of microscopic stress fields at crack tips on the random orientation of neighboring grains

Cizelj, Leon

278

Modelling of residual stresses in the shot peened material C-1020 by artificial neural network  

Science Conference Proceedings (OSTI)

This study consists of two cases: (i) The experimental analysis: Shot peening is a method to improve the resistance of metal pieces to fatigue by creating regions of residual stress. In this study, the residual stresses induced in steel specimen type ... Keywords: Artificial neural network, Layer removal technique, Residual stresses, Shot peening

Cetin Karata?; Adnan Sozen; Emrah Dulek

2009-03-01T23:59:59.000Z

279

X-ray microdiffraction: local stress distributions in polycrystalline and epitaxial thin films  

Science Conference Proceedings (OSTI)

When investigated by X-ray microdiffraction, the stress states in thin metal films are found to be more complex than as assumed by the simple models that have been formulated to describe their behavior. In this paper, the local differences in stress ... Keywords: Al, Al-Cu, Cu, microdiffraction, plasticity, size effects, stress measurement, synchrotron, thin films

M. A. Phillips; R. Spolenak; N. Tamura; W. L. Brown; A. A. MacDowell; R. S. Celestre; H. A. Padmore; B. W. Batterman; E. Arzt; J. R. Patel

2004-07-01T23:59:59.000Z

280

DEVELOPMENT OF PLASTICITY MODEL USING NON ASSOCIATED FLOW RULE FOR HCP MATERIALS INCLUDING ZIRCONIUM FOR NUCLEAR APPLICATIONS  

SciTech Connect

In this report (prepared in collaboration with Prof. Jeong Whan Yoon, Deakin University, Melbourne, Australia) a research effort was made to develop a non associated flow rule for zirconium. Since Zr is a hexagonally close packed (hcp) material, it is impossible to describe its plastic response under arbitrary loading conditions with any associated flow rule (e.g. von Mises). As a result of strong tension compression asymmetry of the yield stress and anisotropy, zirconium displays plastic behavior that requires a more sophisticated approach. Consequently, a new general asymmetric yield function has been developed which accommodates mathematically the four directional anisotropies along 0 degrees, 45 degrees, 90 degrees, and biaxial, under tension and compression. Stress anisotropy has been completely decoupled from the r value by using non associated flow plasticity, where yield function and plastic potential have been treated separately to take care of stress and r value directionalities, respectively. This theoretical development has been verified using Zr alloys at room temperature as an example as these materials have very strong SD (Strength Differential) effect. The proposed yield function reasonably well models the evolution of yield surfaces for a zirconium clock rolled plate during in plane and through thickness compression. It has been found that this function can predict both tension and compression asymmetry mathematically without any numerical tolerance and shows the significant improvement compared to any reported functions. Finally, in the end of the report, a program of further research is outlined aimed at constructing tensorial relationships for the temperature and fluence dependent creep surfaces for Zr, Zircaloy 2, and Zircaloy 4.

Michael V. Glazoff; Jeong-Whan Yoon

2013-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation  

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

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Globus Ruth NASA Ames Research Center Abstract Osteoporosis profoundly affects the aging U.S. population and exposure to high doses of radiation causes bone loss similar to age-related osteoporosis, although the influence of low dose radiation exposures is not known. The central hypothesis of our DOE project (NASA supplement) is that low doses of radiation modulate subsequent skeletal degeneration via oxidative pathways. Our working hypothesis is that a prior exposure to low dose radiation regulates oxidative metabolism within bone and contributes to bone loss caused either by subsequent high, challenge doses of radiation or by aging. HZE source: Because astronauts are exposed to radiation from GCR and solar

282

Residual stress measurement using the pulsed neutron source at LANSCE  

Science Conference Proceedings (OSTI)

The presence of residual stress in engineering components can effect their mechanical properties and structural integrity. Neutron diffraction is the only measuring technique which can make spatially resolved non-destructive strain measurements in the interior of components. By recording the change in the crystalline interplanar spacing, elastic strains can be measured for individual lattice reflections. Using a pulsed neutron source, all the lattice reflections are recorded in each measurement which allows anisotropic effects to be studied. Measurements made at the Manuel Lujan Jr Neutron Scattering Centre (LANSCE) demonstrate the potential for stress measurements on a pulsed source and indicate the advantages and disadvantages over measurements made on a reactor. 15 refs., 7 figs.

Bourke, M.A.M.; Goldstone, J.A. (Los Alamos National Lab., NM (USA)); Holden, T.M. (Atomic Energy of Canada Ltd., Chalk River, ON (Canada))

1991-01-01T23:59:59.000Z

283

Stress analysis of a hybrid composite drilling riser  

E-Print Network (OSTI)

Methods to thoroughly and efficiently analyze a composite riser designed for use in offshore drilling applications and subjected to various types of loading have been developed. An axisymmetric finite element model allowing nonaxisymmetric deformations has been constructed. 'the model was simplified by exploiting symmetries in the lay-up of the composite to homogenize material properties. Postprocessing techniques to recover ply level stresses and strains and determine lamina failures were also developed. The analysis is demonstrated on an industry-designed riser, and the results show that the current design is unacceptable. Even at normal operating loads, there is some failure and some very high stress levels. The analysis is used to suggest modifications to the baseline design.

Sundstrom, Keith Andrew

1996-01-01T23:59:59.000Z

284

Changes in chromatin state in donors subjected to physical stress  

E-Print Network (OSTI)

The purpose of the present study is to evaluate changes in chromatin of human buccal epithelium under the influence of stressing factor - dosed physical activity. Investigations were performed in a group of students (13 men) of age 19-23. Cells were stained on a slide by a 2% orcein solution in 45% acetic acid during 1 h. The following physiological indexes were determined: arterial blood pressure, pulse frequency, and frequency of breathing. The physical stress produced by the dosed physical activity causes the considerable increase of degree of heterochromatinization in the cell nuclei of human buccal epithelium. As a rule, the level of heterochromatinization increases after first stage of training, but in some donors it increases significantly only after the second stage of training.

Yuriy Shckorbatov; Valeriy Samokhvalov; Dariya Bevziuk; Maxim Kovaliov

2009-01-31T23:59:59.000Z

285

Modeling and experimental measurements of residual stress using synchrotron radiation  

SciTech Connect

This work was an extension of recent LLNL-related efforts to determine the most effective method for determining residual stress in metal components by non-destructive techniques. These activities have included neutron diffraction, x-ray diffraction, and ultrasonics. In 1988, we recognized that the newly installed UC/LLNL beam line at the Stanford Synchrotron Radiation Laboratory (SSRL) could be applied to determining lattice strains in a fashion helpful to our overall research goals. Pioneering work using synchrotron radiation for stress measurements had been reported in Japan. Benefits of a synchrotron source to our studies include a highly intense and monochromatic beam, with variable energies (allowing significant sample penetration) and very low beam divergence. 10 refs., 3 figs., 2 tabs.

Shackelford, J.F.

1989-05-08T23:59:59.000Z

286

Stress corrosion cracking of candidate waste container materials  

SciTech Connect

Six alloys have been selected as candidate container materials for the storage of high-level nuclear waste at the proposed Yucca Mountain site in Nevada. These materials are Type 304L stainless steel (SS), Type 316L SS, Incology 825, P-deoxidized Cu, Cu-30%Ni, and Cu-7% Al. The present program has been initiated to determine whether any of these materials can survive for 300 years in the site environment without developing through-wall stress corrosion cracks, and to assess the relative resistance of these materials to stress corrosion cracking (SCC). A series of slow-strain-rate tests (SSRTs) in simulated Well J-13 water which is representative of the groundwater present at the Yucca Mountain site has been completed, and crack-growth-rate (CGR) tests are also being conducted under the same environmental conditions. 13 refs., 60 figs., 22 tabs.

Maiya, P.S.; Soppet, W.K.; Park, J.Y.; Kassner, T.F.; Shack, W.J.; Diercks, D.R.

1990-11-01T23:59:59.000Z

287

Residual stress analysis of multilayer environmental barrier coatings.  

DOE Green Energy (OSTI)

Silicon-based ceramics (SiC, Si{sub 3}N{sub 4}) are promising materials systems for high-temperature structural applications in gas turbine engines. However, the silica layer that forms on these materials is susceptible to attack from water vapor present in combustion environments. To protect against this degradation, environmental barrier coatings (EBCs) have been developed to shield the underlying substrate and prevent degradation. Here we report on elastic and thermal properties, as well as internal stresses of candidate multilayer coatings, as measured in situ using microfocused high-energy X-rays in a transmission diffraction geometry. Doped aluminosilicate coatings were investigated for their stability on a SiC/SiC melt-infiltrated substrate. The coatings consisted of a Ba{sub 1-x}Sr{sub x}Al{sub 2}Si{sub 2}O{sub 8} topcoat with a mullite or mullite+SrAl{sub 2}Si{sub 2}O{sub 8} interlayer, and a silicon bond coat. A numerical model was used to compare the stress results with an ideal coating system. Experiments were carried out on as-sprayed and heat-treated samples in order to analyze the strain and phase evolution as a function of multilayer depth and temperature. The phase transformation of the topcoat promoted healing of cracks in the EBC and reduced stresses in the underlying layers and the addition of SAS to the interlayer reduced stresses in thermally cycled coatings, but did not stop cracks from forming.

Harder, B.; Almer, J.; Weyant, C.; Lee, K.; Faber, K.; Northwestern Univ.; Rolls-Royce Corp.

2009-02-01T23:59:59.000Z

288

Stress relief cracking in creep resisting low alloy ferritic steels.  

E-Print Network (OSTI)

The Problem of Stress Relief Cracking in Low Alloy Steels During the welding of a ferritic steel, the HAZ adjacent to the weld transforms to austenite, the grains close to the fusion zone attaining particularly high tempel'ature and undergoing considerable... growth. At the same time, carbides tend to dissolve, dissolution being more complete in the coarse 14 grained region because it attains a higher temperature. The HAZ is cooled rapidly by the cold parent metal and, as a result, re- precipitation...

Tait, Robert Andrew

1976-10-26T23:59:59.000Z

289

Stress Indices for Straight Pipe with Trunnion Attachments  

Science Conference Proceedings (OSTI)

This report provides equations based on experimental and test data for determining B and C stress indices and the flexibility factor, k, for straight pipe with trunnions (or hollow circular cross-section welded attachments). The report contains explicit modifications to ASME Code Cases 391 and 392 for qualification of trunnions on pipe. It also provides flexibility equations for a more accurate evaluation of these configurations.

1998-11-10T23:59:59.000Z

290

Evaluation of Fundamental Linkage Among Stress Corrosion Cracking (SCC) Phenomena  

Science Conference Proceedings (OSTI)

Many in-core components of stainless steels in light water reactors (LWRs) are susceptible to a degradation process known as irradiation assisted stress corrosion cracking (IASCC). This report describes the results of environmental testing on irradiated Type 304 stainless steel in boiling water reactor (BWR) and pressurized water reactor (PWR) environments to assess their susceptibility to IASCC. The work was sponsored by the Cooperative IASCC Research (CIR I) Program, an international research effort ma...

2002-10-23T23:59:59.000Z

291

Stress corrosion cracking of austenitic stainless steel core internal welds.  

SciTech Connect

Microstructural analyses by several advanced metallographic techniques were conducted on austenitic stainless steel mockup and core shroud welds that had cracked in boiling water reactors. Contrary to previous beliefs, heat-affected zones of the cracked Type 304L, as well as 304 SS core shroud welds and mockup shielded-metal-arc welds, were free of grain-boundary carbides, which shows that core shroud failure cannot be explained by classical intergranular stress corrosion cracking. Neither martensite nor delta-ferrite films were present on the grain boundaries. However, as a result of exposure to welding fumes, the heat-affected zones of the core shroud welds were significantly contaminated by oxygen and fluorine, which migrate to grain boundaries. Significant oxygen contamination seems to promote fluorine contamination and suppress thermal sensitization. Results of slow-strain-rate tensile tests also indicate that fluorine exacerbates the susceptibility of irradiated steels to intergranular stress corrosion cracking. These observations, combined with previous reports on the strong influence of weld flux, indicate that oxygen and fluorine contamination and fluorine-catalyzed stress corrosion play a major role in cracking of core shroud welds.

Chung, H. M.; Park, J.-H.; Ruther, W. E.; Sanecki, J. E.; Strain, R. V.; Zaluzec, N. J.

1999-04-14T23:59:59.000Z

292

Overpressure prediction by mean total stress estimate using well logs for compressional environments with strike-slip or reverse faulting stress state  

E-Print Network (OSTI)

Predicting correct pore-pressure is important for drilling applications. Wellbore stability problems, kicks, or even blow-outs can be avoided with a good estimate of porepressure. Conventional pore-pressure estimation methods are based on one-dimensional compaction theory and depend on a relationship between porosity and vertical effective stress. Strike-slip or reverse faulting environments especially require a different way to determine pore-pressure, since the overburden is not the maximum stress. This study proposes a method which better accounts for the three-dimensional nature of the stress field and provides improved estimates of pore-pressure. We apply the mean total stress estimate to estimate pore-pressure. Pore pressure is then obtained by modifying Eaton�s pore-pressure equations, which require either resistivity or sonic log data. The method was tested in the Snorre Field in the Norwegian North Sea, where the field changes from strike-slip to reverse stress state. Eaton�s resistivity and sonic equations were used to predict pore-pressure in this region by replacing the vertical stress by the mean total stress estimate. Results suggest that the modified Eaton method with resistivity log data gives better results for the area than the conventional method. The ratio of maximum horizontal stress to minimum horizontal stress throughout each well should be known for best results.

Ozkale, Aslihan

2006-12-01T23:59:59.000Z

293

Earth stress measurements in the South Belridge oil field, Kern County, California  

SciTech Connect

The authors report earth stress magnitudes in the South Belridge oil field, determined from integrated density logs and microhydraulic fracturing test. They indicate that the vertical stress is generally the intermediate principal stress, except possibly at the deepest zone tested (2,100 ft (640 m)), where it is approximately equal to the lesser compressive horizontal stress. Azimuth of the greater horizontal stress and of induced hydraulic fractures, as measured or inferred by several different techniques, is N15{sup 0}E+-15{sup 0}.

Hansen, K.S.; Purcell, W.R. (Shell Development Co., Houston, TX (US))

1989-12-01T23:59:59.000Z

294

Earth stress measurements in the South Belridge oil field, Kern County, California  

Science Conference Proceedings (OSTI)

Within Sections 33 and 34 of the South Belridge oil field, where the principal earth stresses are assumed to lie in vertical or horizontal planes, the azimuth of the greater horizontal earth stress as measured or inferred by several different techniques is N15/sup 0/E +. 15/sup 0/. This agrees with values reported in the literature for the regional stress orientation, which range from N-S to NNE-SSW. At depths of about 850 and 1300 feet, the magnitude of the vertical stress (overburden) lies between those of the greater and lesser horizontal stresses determined from open-hole microfrac tests. At about 2100 feet, however, the vertical and lesser horizontal stresses are equal, to within the limits of accuracy of the authors' measurements. If trends of stress versus depth established at the three measurement points continue downward, there is the possibility that at depths below 2100 feet the minimum stress may be vertical. The most reliable methods used for determining in-situ stress orientation at South Belridge are surface tiltmeters and orientation of out-of-round (elliptical) boreholes. Study of natural fractures in the nearby Chico-Martinez Creek outcrop provided important supporting evidence of stress orientation. Impression packers run during the microfrac tests and seismic data recorded during routine hydraulic fracturing procedures yielded much less definitive information concerning fracture and stress direction.

Hansen, K.S.; Purcell, W.R.

1986-01-01T23:59:59.000Z

295

EXPOS ET MISE AU POINT BIBLIOGRAPHIQUE LA FORMATION DES PARTICULES DE CARBONE DANS LES FLAMMES  

E-Print Network (OSTI)

des fours, qu'ils soient aciéristes, verriers, ou cimentiers. On sait que le rayonnement des flammes d'hydro cristaux de noir d'acéty- lène peut être due à la présence d'atomes interstitiels d'hydrogène, car on trouve généralement 1 % d'hydro- gène dans les dépôts de carbone-suie. Pour certains auteurs la structure

Paris-Sud XI, Université de

296

Ein Bild fr die Geschichtsbcher: Professor Kurt Wthrich empfngt am 10. Dezember in Stockholm aus den Hnden von Schwedens Knig Carl XVI Gustaf den Chemie-Nobelpreis 2002. F O T O : K E Y S T O N E / E P A / H E N R I K M O N T G O M E R Y  

E-Print Network (OSTI)

aus den Händen von Schwedens König Carl XVI Gustaf den Chemie-Nobelpreis 2002. F O T O : K E Y S T O N Geehrten auch zwei japanische Wissenschaf- ter (Masatoshi Koshiba in Physik und Koichi Tanaka in Chemie Stockholm konnte Professor Kurt Wüth- rich den Nobelpreis für Chemie entgegennehmen. Der ETH-For- scher

Giger, Christine

297

Simulation and analysis of Magnetically-Applied Pressure-Shear (MAPS) experiments.  

SciTech Connect

A new experimental technique to measure material shear strength at high pressures has been developed for use on magnetohydrodynamic (MHD) drive pulsed power platforms. The technique is referred to as Magnetically-Applied Pressure-Shear (MAPS). By applying an external static magnetic field to the sample region, the MHD drive directly induces a shear stress wave in addition to the usual longitudinal stress wave. Strength is probed by passing this shear wave through a sample material where the transmissible shear stress is limited to the sample strength. The magnitude of the transmitted shear wave is measured via a transverse velocity interferometry system (VISAR) from which the sample strength is determined. The strength of materials is defined as the ability of a material to sustain deviatoric (shear) stresses. Strength is an important aspect of the response of materials subjected to compression to high pressure. Beyond the elastic response, material strength will govern at what pressure and to what extent a material will plastically deform. The MAPS technique cleverly exploits the property that, for a von Mises yield criterion at a given longitudinal stress, the maximum amplitude shear wave that can be transmitted is limited by the strength at that stress level. Successful fielding of MAPS experiments to measure shear stresses relies upon correct numerical simulation of the experiment. Complex wave interactions among forward and reflected longitudinal and shear waves, as well as the advancing magnetic diffusion front of the MHD drive, can make the design of the experiment complicated. Careful consideration must be given to driver, sample, and anvil materials; to the thicknesses of the driver, sample and anvil layers; as well as to the timing of the interacting waves. This paper will present and analyze the 2D MHD simulations used to design the MAPS experiments. The MAPS experiments are modeled using Sandia's ALEGRA-MHD simulation code. ALEGRA-MHD is an operator-split, multi-physics, multi-material, arbitrary lagrangian-eulerian code developed to model magnetic implosion, ceramic fracture, and electromagnetic launch. We will detail the numerical investigations into MHD shear generation, longitudinal and shear stress coupling, timing of wave interactions, and transmission of shear at material interfaces.

Haill, Thomas A.; Alexander, C. Scott; Asay, James Russell

2011-06-01T23:59:59.000Z

298

Stress corrosion cracking of zirconium in nitric acid  

Science Conference Proceedings (OSTI)

The susceptibility of zirconium and its common alloys to stress corrosion cracking (SCC) in nitric acid was investigated by slow strain-rate and constant deflection techniques. Cracking occurred at 25/sup 0/C over a wide range of acid concentrations and electrochemical potentials. The crack velocity increased slightly with increasing temperature. The failure mode was transgranular and the morphology was similar to SCC failures of zirconium alloys in other environments. The fracture was very orientation-dependent suggesting that it occurs on a single crystallographic plane in the material. The results of the study are not consistent with a hydrogen mechanism for cracking.

Beavers, J.A.; Griess, J.C.; Boyd, W.K.

1980-01-01T23:59:59.000Z

299

Stress corrosion cracking of candidate waste container materials; Final report  

Science Conference Proceedings (OSTI)

Six alloys have been selected as candidate container materials for the storage of high-level nuclear waste at the proposed Yucca mountain site in Nevada. These materials are Type 304L stainless steel (SS). Type 316L SS, Incoloy 825, phosphorus-deoxidized Cu, Cu-30%Ni, and Cu-7%Al. The present program has been initiated to determine whether any of these materials can survive for 300 years in the site environment without developing through-wall stress corrosion cracks. and to assess the relative resistance of these materials to stress corrosion cracking (SCC)- A series of slow-strain-rate tests (SSRTs) and fracture-mechanics crack-growth-rate (CGR) tests was performed at 93{degree}C and 1 atm of pressure in simulated J-13 well water. This water is representative, prior to the widespread availability of unsaturated-zone water, of the groundwater present at the Yucca Mountain site. Slow-strain-rate tests were conducted on 6.35-mm-diameter cylindrical specimens at strain rates of 10-{sup {minus}7} and 10{sup {minus}8} s{sup {minus}1} under crevice and noncrevice conditions. All tests were interrupted after nominal elongation strain of 1--4%. Scanning electron microscopy revealed some crack initiation in virtually all the materials, as well as weldments made from these materials. A stress- or strain-ratio cracking index ranks these materials, in order of increasing resistance to SCC, as follows: Type 304 SS < Type 316L SS < Incoloy 825 < Cu-30%Ni < Cu and Cu-7%Al. Fracture-mechanics CGR tests were conducted on 25.4-mm-thick compact tension specimens of Types 304L and 316L stainless steel (SS) and Incoloy 825. Crack-growth rates were measured under various load conditions: load ratios M of 0.5--1.0, frequencies of 10{sup {minus}3}-1 Hz, rise nines of 1--1000s, and peak stress intensities of 25--40 MPa{center_dot}m {sup l/2}.

Park, J.Y.; Maiya, P.S.; Soppet, W.K.; Diercks, D.R.; Shack, W.J.; Kassner, T.F. [Argonne National Lab., IL (United States)

1992-06-01T23:59:59.000Z

300

Interfacial stress in a carbon-to-metal bond joint under thermal shock loading  

SciTech Connect

The duplex bond joint consisting of a metallic substrate armored with carbon-base materials is a promising candidate configuration for application to high heat flux operations. When a bond joint is subjected to thermal loadings, significant thermal stresses may develop due to mismatch of the thermal expansion coefficients. Stress intensification occurs near the free surface edge of the interface, sometimes showing singularity. The singular stress fields are critical for understanding the loading nature of the bond interface in a joint system. In this paper, thermal stresses in the bond interface of a carbon-to-molybdenum joint element were investigated. A high heat flux (HHF) pulse was assumed as the reference load history to simulate the thermal shock condition. The thermomechanical behavior was described quantitatively in terms of the stress intensity factor. The stress solutions of the singular field computed by the theoretical approach showed a good agreement with the numerical results of the finite element analysis. The stress intensity factor of the singular stress fields near the free surface edge of the interface showed a time variation similar to that of the bulk stress. The temperature gradient induced by the transient HHF load affected the overall interfacial stress only slightly.

You, J.H. [Forschungszentrum Juelich (Germany). Inst. for Materials in Energy Systems] [Forschungszentrum Juelich (Germany). Inst. for Materials in Energy Systems

1998-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Physical aging and relaxation of residual stresses in a colloidal glass following flow cessation  

E-Print Network (OSTI)

Dilute Laponite suspensions in water at low salt concentration form repulsive colloidal glasses which display physical aging. This phenomenon is still not completely understood and in particular, little is known about the connection between the flow history, as a determinant of the initial state of the system, and the subsequent aging dynamics. Using a stress controlled rheometer, we perform stress jump experiments to observe the elastic component of the flow stress that remains on cessation of flow or flow quenching. We investigate the connection between the dynamics of these residual stresses and the rate of physical aging upon quenching from different points on the steady state flow curve. Quenching from high rates produces a fluid state, G">G', with small, fast relaxing residual stresses and rapid, sigmoidal aging of the complex modulus. Conversely, quenching from lower shear rates produces increasingly jammed states featuring slowly relaxing stresses and a slow increase of the complex modulus with system age. Flow cessation from a fixed shear rate with varying quench durations shows that slower quenches produce smaller residual stresses at short times which relax at long times by smaller extents, by comparison with faster quenches. These smaller stresses are correlated with a higher modulus but slower physical aging of the system. The characteristic time for the residual stress relaxation scales inversely with the quench rate. This implies a frustrated approach to any ideal stress-free state that succinctly reflects the frustrated nature of these glassy systems.

Ajay Singh Negi; Chinedum O. Osuji

2010-04-09T23:59:59.000Z

302

Effect of couple-stress on the pure bending of a prismatic bar  

SciTech Connect

An evaluation of the applicability of the couple-stress theory to the stress analysis of graphite structures is performed by solving a pure bending problem. The differences between solutions from the couple-stress theory and from the classical theory of elasticity are compared. It is found that the differences are sufficient to account for the inconsistencies which have often been observed between the classical elasticity theory and actual behavior of graphite under bend and tensile loadings. An experimental procedure to measure the material constants in the couple-stress theory is also suggested. The linear couple-stress theory, the origins of which go back to the turn of the last century, adds linear relations between couple-stresses and rotation gradients to the classical stress-strain law. By adopting the classical assumption that the plane cross section remains plane after deformation, the pure-bending problem is reduced to a plane couple-stress problem with traction-free boundary conditions. A general solution for an isotropic elastic prismatic bar under pure bending is then obtained using the Airy stress function and another stress function wich accounts for the couple-stresss. For a cylindrical bar, it reduces to a simple series solution. The moment-curvature and stress-curvature relations derived for a cylindrical bar from the general solution are used to examine the effect of couple-stresses. Numerical compilation of relations indicates that the couple stress parameters can be practically determined by measuring the moment-curvature ratio of various diametered specimens under bending. Although there is not sufficient data for such evaluation at present, it appears that the theory is consistent with the limited bend and tensile strength data of cylindrical specimens for H-451 graphite.

Tzung, F.; Kao, B.; Ho, F.; Tang, P.

1981-02-01T23:59:59.000Z

303

THERMAL STRESS CALCULATIONS FOR HEATPIPE-COOLED REACTOR POWER SYSTEMS.  

DOE Green Energy (OSTI)

A heatpipe-cooled fast reactor concept has been under development at Los Alamos National Laboratory for the past several years, to be used as a power source for nuclear electric propulsion (NEP) or as a planetary surface power system. The reactor core consists of an array of modules that are held together by a core lateral restraint system. Each module comprises a single heatpipe surrounded by 3-6 clad fuel pins. As part of the design development and performance assessment activities for these reactors, specialized methods and models have been developed to perform thermal and stress analyses of the core modules. The methods have been automated so that trade studies can be readily performed, looking at design options such as module size, heatpipe and clad thickness, use of sleeves to contain the fuel, material type, etc. This paper describes the methods and models that have been developed, and presents thermal and stress analysis results for a Mars surface power system and a NEP power source.

Kapernick, R. J. (Richard J.); Guffee, R. M. (Ray M.)

2001-01-01T23:59:59.000Z

304

Stress in accident and post-accident management at Chernobyl ?  

E-Print Network (OSTI)

Abstract. The effects of the Chernobyl nuclear accident on the psychology of the affected population have been much discussed. The psychological dimension has been advanced as a factor explaining the emergence, from 1990 onwards, of a post-accident crisis in the main CIS countries affected. This article presents the conclusions of a series of European studies, which focused on the consequences of the Chernobyl accident. These studies show that the psychological and social effects associated with the post-accident situation arise from the interdependency of a number of complex factors exerting a deleterious effect on the population. We shall first attempt to characterise the stress phenomena observed among the population affected by the accident. Secondly, we will be presenting an analysis of the various factors that have contributed to the emerging psychological and social features of population reaction to the accident and in post-accident phases, while not neglecting the effects of the pre-accident situation on the target population. Thirdly, we shall devote some initial consideration to the conditions that might be conducive to better management of postaccident stress. In conclusion, we shall emphasise the need to restore confidence among the population generally. 1.

Gilles Heriard Dubreuil

1996-01-01T23:59:59.000Z

305

Computer Simulation of Intergranular Stress Corrosion Cracking via Hydrogen Embrittlement  

DOE Green Energy (OSTI)

Computer simulation has been applied to the investigation of intergranular stress corrosion cracking in Ni-based alloys based on a hydrogen embrittlement mechanism. The simulation employs computational modules that address (a) transport and reactions of aqueous species giving rise to hydrogen generation at the liquid-metal interface, (b) solid state transport of hydrogen via intergranular and transgranular diffusion pathways, and (c) fracture due to the embrittlement of metallic bonds by hydrogen. A key focus of the computational model development has been the role of materials microstructure (precipitate particles and grain boundaries) on hydrogen transport and embrittlement. Simulation results reveal that intergranular fracture is enhanced as grain boundaries are weakened and that microstructures with grains elongated perpendicular to the stress axis are more susceptible to cracking. The presence of intergranular precipitates may be expected to either enhance or impede cracking depending on the relative distribution of hydrogen between the grain boundaries and the precipitate-matrix interfaces. Calculations of hydrogen outgassing and in gassing demonstrate a strong effect of charging method on the fracture behavior.

Smith, R.W.

2000-04-01T23:59:59.000Z

306

Analysis of Alloy 600 and X-750 stress corrosion cracks  

Science Conference Proceedings (OSTI)

A few months ago, KAPL evidence supported the view that Primary or Pure Water Stress Corrosion Cracking (PWSCC) of Alloy 600 results from a hydrogen mechanism. Figure 1 shows an Analytical Electron Microscope (AEM) analysis of a stress corrosion crack (SCC) crack in an A600 split tube U-bend specimen exposed to primary water at 338{degree}C (640{degrees}F) for 462 days. The features which appear to confirm a hydrogen mechanism are: (1) A very narrow (< 200 {angstrom}) crack with a sharp tip, nearly free of deposits. (2) No evidence of severe plastic deformation in the region immediately ahead of the crack tip. (3) A line of small voids preceding the main crack tip, of which the largest is about 5 x 10{sup {minus}6} cm in length. Shen and Shewmon proposed that PWSCC of Alloy 600 occurs due to small microvoids ahead of a main crack tip. The hypothesis is that such voids result from pockets of methane gas formed by the reaction of atomic hydrogen with carbon in the base metal. The voids are about 10 x 10{sup {minus}6} cm diameter, approximately a factor of 2 larger than the largest voids.

Thompson, C.D.; Lewis, N.; Krasodomski, H.

1993-06-01T23:59:59.000Z

307

Oxidative Stress Mediates Radiation Lung Injury by Inducing Apoptosis  

SciTech Connect

Purpose: Apoptosis in irradiated normal lung tissue has been observed several weeks after radiation. However, the signaling pathway propagating cell death after radiation remains unknown. Methods and Materials: C57BL/6J mice were irradiated with 15 Gy to the whole thorax. Pro-apoptotic signaling was evaluated 6 weeks after radiation with or without administration of AEOL10150, a potent catalytic scavenger of reactive oxygen and nitrogen species. Results: Apoptosis was observed primarily in type I and type II pneumocytes and endothelium. Apoptosis correlated with increased PTEN expression, inhibition of downstream PI3K/AKT signaling, and increased p53 and Bax protein levels. Transforming growth factor-{beta}1, Nox4, and oxidative stress were also increased 6 weeks after radiation. Therapeutic administration of AEOL10150 suppressed pro-apoptotic signaling and dramatically reduced the number of apoptotic cells. Conclusion: Increased PTEN signaling after radiation results in apoptosis of lung parenchymal cells. We hypothesize that upregulation of PTEN is influenced by Nox4-derived oxidative stress. To our knowledge, this is the first study to highlight the role of PTEN in radiation-induced pulmonary toxicity.

Zhang Yu; Zhang Xiuwu; Rabbani, Zahid N. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Jackson, Isabel L. [Department of Pathology, Duke University Medical Center, Durham, NC (United States); Vujaskovic, Zeljko, E-mail: vujas@radonc.duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Department of Pathology, Duke University Medical Center, Durham, NC (United States)

2012-06-01T23:59:59.000Z

308

Graphite having improved thermal stress resistance and method of preparation  

DOE Patents (OSTI)

An improved method for fabricating a graphite article comprises the steps of impregnating a coke article by first heating the coke article in contact with a thermoplastic pitch at a temperature within the range of 250.degree.-300.degree. C. at a pressure within the range of 200-2000 psig for at least 4-10 hours and then heating said article at a temperature within the range of 450.degree.-485.degree. C. at a pressure of 200-2000 psig for about 16-24 hours to provide an impregnated article; heating the impregnated article for sufficient time to carbonize the impregnant to provide a second coke article, and graphitizing the second coke article. A graphite having improved thermal stress resistance results when the coke to be impregnated contains 1-3 wt.% sulfur and no added puffing inhibitors. An additional improvement in thermal stress resistance is achieved when the second coke article is heated above about 1400.degree. C. at a rate of at least 10.degree. C./minute to a temperature above the puffing temperature.

Kennedy, Charles R. (Oak Ridge, TN)

1980-01-01T23:59:59.000Z

309

Contact and Stress Anisotropies in Start-Up Flow of Colloidal Suspensions |  

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

Contact and Stress Anisotropies in Start-Up Flow of Colloidal Suspensions Contact and Stress Anisotropies in Start-Up Flow of Colloidal Suspensions Submitted by Anonymous on November 3, 2011 - 12:52 Authors: Martys, N.S., Lootens, D., George, W., and H Spatiotemporal correlations in start-up flows of attractive colloids are explored by numerical simulations as a function of their volume fraction and shear rate. The suspension is first allowed to flocculate during a time tw, then the stress necessary to induce its flow is computed. We find that, at low volume fractions, the stress is a universal function of the strain. On the contrary, at high volume fractions, this scaling behavior is no longer observed and a supplementary stress becomes necessary to induce flow. To better understand the physical origin of the supplementary stress,

310

STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND RECENT RESULTS  

Open Energy Info (EERE)

STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND RECENT RESULTS STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND RECENT RESULTS FROM THE EAST FLANK AND COSO WASH Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND RECENT RESULTS FROM THE EAST FLANK AND COSO WASH Details Activities (1) Areas (1) Regions (0) Abstract: We integrate new geologic mapping and measurements of stress orientations and magnitudes from wells 34-9RD2 and 58A-10 with existing data sets to refine a geomechanical model for the Coso geothermal field. Vertically averaged stress orientations across the field are fairly uniform and are consistent with focal mechanism inversions of earthquake clusters for stress and incremental strain. Active faults trending NNW-SSE to

311

Borehole Imaging of In Situ Stress Tests at Mirror Lake Research Site |  

Open Energy Info (EERE)

Borehole Imaging of In Situ Stress Tests at Mirror Lake Research Site Borehole Imaging of In Situ Stress Tests at Mirror Lake Research Site Jump to: navigation, search OpenEI Reference LibraryAdd to library Web Site: Borehole Imaging of In Situ Stress Tests at Mirror Lake Research Site Author U.S. Geological Survey Published U.S. Geological Survey, 2013 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Borehole Imaging of In Situ Stress Tests at Mirror Lake Research Site Citation U.S. Geological Survey. Borehole Imaging of In Situ Stress Tests at Mirror Lake Research Site [Internet]. 2013. U.S. Geological Survey. [cited 2013/10/16]. Available from: http://water.usgs.gov/ogw/bgas/toxics/ml_bips.html Retrieved from "http://en.openei.org/w/index.php?title=Borehole_Imaging_of_In_Situ_Stress_Tests_at_Mirror_Lake_Research_Site&oldid=688729"

312

STRESS ANALYSIS OF SPECIMENS FOR IN-PILE CREEP TESTS OF PARABOLIC GRAPHITE BEAMS  

SciTech Connect

The irradiation-induced creep of graphite is being investigated in experiments that consist of loading parabolically shaped cantilever beams at the free end and measuring the resulting deflections with time. A series of stress analyses was made to verify the applicability of the elementary strength-of- materials approach for obtaining relations between stress and creep strain from the load-deflection data. The results of the analyses, which included a theory- of-elasticity solution, an evaluation of the effect of shear, and a bending analysis using an actual stress-strain diagram for graphite, show that an elementary strength-of-materials approach is adequate to predict the initial or elastic stresses. Preliminary results from the in-pile experiments indicate that the creep strains are linear with stress; thus the initially linear bending stress distribution given by the elementary theory remains unchanged during creep. (auth)

Corum, J.M.

1964-02-01T23:59:59.000Z

313

Design of a triaxial residual stress measurement system using high energy x-ray diffraction  

Science Conference Proceedings (OSTI)

Previous design studies in developing concepts for residual stress measurement in engineering materials have been extended. A pre-prototype energy dispersive x-ray diffraction (EDXRD) system has been fabricated. A 300 kV radiography source is used in conjunction with an intrinsic germanium detector and a MacII/LabVIEW data acquisition system. Specimens up to 25mm equivalent steel thickness (and one meter gross dimensions) can now be evaluated. The pre-prototype system serves as the hard x-ray, bulk stress measurement component of the previously reported hybrid stress measuring system (which would include a traditional multi-angle surface measurement system using soft x-rays). In addition, a detailed study of residual stress analytical equations has been completed and applied to various metallic and ceramic materials. During the grant period, related studies were completed on stress measurement using synchrotron radiation and on a critical review of the residual stress literature. 6 refs., 3 figs.

Shackelford, J.F.; Brown, B.D.; Park, J.S.

1989-01-01T23:59:59.000Z

314

Time-aging time-stress superposition in soft glass under tensile deformation field  

E-Print Network (OSTI)

We have studied the tensile deformation behaviour of thin films of aging aqueous suspension of Laponite, a model soft glassy material, when subjected to a creep flow field generated by a constant engineering normal stress. Aqueous suspension of Laponite demonstrates aging behaviour wherein it undergoes time dependent enhancement of its elastic modulus as well as its characteristic relaxation time. However, under application of the normal stress, the rate of aging decreases and in the limit of high stress, the aging stops with the suspension now undergoing a plastic deformation. Overall, it is observed that the aging that occurs over short creep times at small normal stresses is same as the aging that occurs over long creep times at large normal stresses. This observation allows us to suggest an aging time - process time - normal stress superposition principle, which can predict rheological behaviour at longer times by carrying out short time tests.

Asima Shaukat; Ashutosh Sharma; Yogesh M. Joshi

2010-06-10T23:59:59.000Z

315

Shallow hydraulic fracturing measurements in Korea support tectonic and seismic indicators of regional stress.  

Science Conference Proceedings (OSTI)

We have conducted five hydraulic fracturing stress measurement campaigns in Korea, involving 13 test holes ranging in depth from 30 to 250 m, at locations from North Seoul to the southern coast of the peninsula. The measurements reveal consistent crustal stress magnitudes and directions that suggest persistence throughout western and southern Korea. The maximum horizontal stress {sigma}{sub H} is oriented between ENE-WSW and E-W, in accord with plate movement and deformation, and with directions indicated by both focal mechanism solutions from earthquakes inland and offshore as well as borehole breakouts in mainland China close to its eastern coast. With respect to magnitudes, the vertical stress is the overall minimum stress at all tested locations, suggesting a thrust faulting regime within the relatively shallow depths reached by our tests. Typically, such a stress regime becomes one favoring strike-slip at greater depths, as is also indicated by the focal mechanism solutions around Korea.

Haimson, Bezalel Cecil (University of Wisconsin, Madison, WI); Lee, Moo Yul; Song, I. (Ruhr-University Bochum, Bochum, Germany)

2003-07-01T23:59:59.000Z

316

In Situ Stress Measurements in the NPR Hole, Volume I - Results and Interpretations  

Science Conference Proceedings (OSTI)

This report presents the results of an investigation of the magnitudes and orientations of the in situ stresses in basement rocks beneath the Savannah River Site (SRS). Stress magnitudes were measured using the hydraulic fracturing technique. Stress orientations were obtained from the orientation of stress-induced wellbore breakouts and hydraulically-induced fractures. The measurements reported here were carried out in the New Production Reactor (NPR) hole, drilled to a total depth of 4000 feet near the center of the Savannah River Site, at roughly the location of the proposed NPR. The results obtained in this study are compared to previous stress measurements made using the same techniques in a series of shallower holes on the SRS, and discussed in the context of the regional stress field and potential seismic hazard.

Moos, D.

2001-10-15T23:59:59.000Z

317

Design of an Aluminum Proton Beam Window for the Spallation Neutron Source  

Science Conference Proceedings (OSTI)

An aluminum proton beam window design is being considered at the Spallation Neutron Source primarily to increase the lifetime of the window, with secondary advantages of higher beam transport efficiency and lower activation. The window separates the core vessel, the location of the mercury target, from the vacuum of the accelerator, while withstanding the pass through of a proton beam of up to 2 MW with 1.0 GeV proton energy. The current aluminum alloy being investigated for the window material is 6061-T651 due to its combination of high strength, high thermal conductivity, and good resistance to aqueous corrosion, as well as demonstrated dependability in previous high-radiation environments. The window design will feature a thin plate with closely spaced cross drilled cooling holes. An analytical approach was used to optimize the dimensions of the window before finite element analysis was used to simulate temperature profiles and stress fields resulting from thermal and static pressure loading. The resulting maximum temperature of 60 C and Von Mises stress of 71 MPa are very low compared to allowables for Al 6061-T651. A significant challenge in designing an aluminum proton beam window for SNS is integrating the window with the current 316L SS shield blocks. Explosion bonding was chosen as a joining technique because of the large bonding area required. A test program has commenced to prove explosion bonding can produce a robust vacuum joint. Pending successful explosion bond testing, the aluminum proton beam window design will be proven acceptable for service in the Spallation Neutron Source.

Janney, Jim G [ORNL; McClintock, David A [ORNL

2012-01-01T23:59:59.000Z

318

Heat Stress Management Program for Power Plants: Clothing Update of EPRI NP-4453-L -- 1991 Report  

Science Conference Proceedings (OSTI)

Clothing ensembles that protect workers from radioactive skin contamination can potentially increase the risk for heat stress. To address this issue, most nuclear power plants calculate action times (stay times) based on the ambient temperature and humidity, work level, and the protective clothing worn. The 1991 EPRI Heat Stress Management Program for Power Plants (report NP-4453-L, Rev. 1) described common methods for evaluating heat stress and provided the necessary adjustment factors for five specific...

1998-08-25T23:59:59.000Z

319

Analytical solution for unsteady thermal stresses in an infinite cylinder composed of two materials  

SciTech Connect

An exact analytical solution for unsteady thermal stresses in an infinitely long solid composite cylinder is presented. The unsteady temperature field is determined following Ozisik's (1980) treatment, but a more general solution is achieved by the present approach by considering a heat convection situation at the outer boundary. The plane stress and plane strain states are considered next, and the thermal stresses are evaluated. Results are provided as dimensionless plots for several combinations of thermal and mechanical parameters of practical interest. 6 references.

Pardo, E.; Sanchez Sarmiento, G.; Laura, P.A.A.; Gutierrez, R.H.

1987-01-01T23:59:59.000Z

320

Dynamic Chromatin Localization of Sirt6 Shapes Stress-and Aging-Related Transcriptional Networks  

E-Print Network (OSTI)

control. Sirt6 can interact with the stress-responsive transcription factor NF-kB and regulate some NF-kB upon stress-signaling. The majority of genes bound by NF-kB subunit RelA recruit Sirt6, and dynamic of NF-kB signaling in stress response and aging. Citation: Kawahara TLA, Rapicavoli NA, Wu AR, Qu K

Quake, Stephen R.

Note: This page contains sample records for the topic "von mises stress" 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

In situ measurements of stress evolution in silicon thin films during  

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

In situ measurements of stress evolution in silicon thin films during In situ measurements of stress evolution in silicon thin films during electrochemical lithiation and delithiation Title In situ measurements of stress evolution in silicon thin films during electrochemical lithiation and delithiation Publication Type Journal Article Year of Publication 2010 Authors Sethuraman, Vijay A., Michael J. Chon, Maxwell Shimshak, Venkat Srinivasan, and Pradeep R. Guduru Journal Journal of Power Sources Volume 195 Start Page 5062 Issue 15 Pagination 5062-5066 Date Published 08/2010 Keywords In situ stress measurement, Lithium-ion battery, Mechanical dissipation, Multi-beam optical sensor (MOS), Open-circuit relaxation, Silicon anode Abstract We report in situ measurements of stress evolution in a silicon thin-film electrode during electrochemical lithiation and delithiation by using the multi-beam optical sensor (MOS) technique. Upon lithiation, due to substrate constraint, the silicon electrode initially undergoes elastic deformation, resulting in rapid rise of compressive stress. The electrode begins to deform plastically at a compressive stress of ca. -1.75 GPa; subsequent lithiation results in continued plastic strain, dissipating mechanical energy. Upon delithiation, the electrode first undergoes elastic straining in the opposite direction, leading to a tensile stress of ca. 1 GPa; subsequently, it deforms plastically during the rest of delithiation. The plastic flow stress evolves continuously with lithium concentration. Thus, mechanical energy is dissipated in plastic deformation during both lithiation and delithiation, and it can be calculated from the stress measurements; we show that it is comparable to the polarization loss. Upon current interruption, both the film stress and the electrode potential relax with similar time constants, suggesting that stress contributes significantly to the chemical potential of lithiated silicon.

322

A HANDBOOK PERTAINING TO MUSIC EDUCATORS' STRESS MANAGEMENT, PHYSICAL ACTIVITY, AND NUTRITION.  

E-Print Network (OSTI)

??The purpose of this study was to write a handbook pertaining to music educators’ stress management, physical activity, and nutrition. In order to obtain information… (more)

Farmer, Sarah Michaelene

2006-01-01T23:59:59.000Z

323

HYDRAULIC FRACTURING AND OVERCORING STRESS MEASUREMENTS IN A DEEP BOREHOLE AT THE STRIPA TEST MINE, SWEDEN  

E-Print Network (OSTI)

u l y 2 , 1 9 8 1 HYDRAULIC FRACTURING AND OVERCORING STRESSI nun LBL-12478 HYDRAULIC FRACTURING AND OVERCORING STRESSthe calculated stress. n HYDRAULIC FRACTURING EQUIPMENT AND

Doe, T.

2010-01-01T23:59:59.000Z

324

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

325

A Platform Towards In Situ Stress/Strain Measurement in Lithium Ion Battery Electrodes.  

E-Print Network (OSTI)

??This thesis demonstrates the design, fabrication and testing of a platform for in situ stress/strain measurement in lithium ion battery electrodes. The platform - consisting… (more)

Baron, Sergio Daniel

2012-01-01T23:59:59.000Z

326

Stress-Assisted Dissolution and Precipitation of Bioglass 45S5  

Science Conference Proceedings (OSTI)

Using microindentation, the stress-assisted-electrical dissolution and precipitation of bioglass ... Manufacturing Bioactive Glass 45S5 by the Sol-Gel Method.

327

Environmental, safety and health standards identification for geothermal energy. Report 6: neat stress  

DOE Green Energy (OSTI)

The following are discussed: the physiological effects of heat stress, monitoring equipment, review of existing standards, and evaluation of existing standards. (MHR)

Quilici, D.G.; Anderson, R.G.; Martin, J.B.

1979-03-01T23:59:59.000Z

328

Large-Scale, Continuous-Flow Production of Stressed Biomass (Desulfovibrio vulgaris Hildenborough)  

E-Print Network (OSTI)

Flow Production of Stressed Biomass (Desulfovibrio vulgaris1391R12 1391P4 Results of Biomass Monitoring Observationsof heterogeneous biomass distribution in PFR: ? Small (1 mm

Geller, Jil T.

2011-01-01T23:59:59.000Z

329

The Study of Stress Corrosion Cracking on Alloy 600 C-Ring ...  

Science Conference Proceedings (OSTI)

... (SCC) have been investigated in stressed C-rings of Alloy 600 boiler tubing. .... INFLUENCE OF PRIMARY WATER CHEMISTRY ON OXIDES FORMED ON ...

330

A new coal-permeability model: Internal swelling stress and fracture-matrix interaction  

E-Print Network (OSTI)

of carbon dioxide in coal with enhanced coalbed methaneL. Adsorption-induced coal swelling and stress: Implicationsand acid gas sequestration into coal seams. J Geophys Res. (

Liu, H.H.

2010-01-01T23:59:59.000Z

331

A New Coal-Permeability Model: Internal Swelling Stress and Fracture–Matrix Interaction  

E-Print Network (OSTI)

L. : Adsorption-induced coal swelling and stress:acid gas sequestration into coal seams. J Geophys. Res. (fracturing on permeability of coal. Min. Sci. Technol. 3,

Liu, Hui-Hai; Rutqvist, Jonny

2010-01-01T23:59:59.000Z

332

E13: An Experimentally-based Flow Stress Model for Cortical Bone  

Science Conference Proceedings (OSTI)

Developed here is a micro-scale-based flow stress model of cortical bone. In order to ... Catalysts by Using the Metal Ion-reducing Bacterium Shewanella Algae.

333

Integrated measures of anthropogenic stress in the U.S. Great Lakes Basin  

Science Conference Proceedings (OSTI)

Using publicly available, pre-existing spatial datasets, we developed a geographic information system database of 86 variables related to five classes of anthropogenic stress in the U.S. Great Lakes basin: agriculture, atmospheric deposition, human population, land cover, and point source pollution. The original variables were quantified by a variety of data types over a broad range of spatial and classification resolutions. We summarized the original data for 762 watershed-based units that comprise the U.S. portion of the basin and then used principal components analysis to develop overall stress measures within each stress category. We developed a cumulative stress index by combining the first principal component from each of the five stress categories. Maps of the stress measures illustrate strong spatial patterns across the basin, with the greatest amount of stress occurring on the western shore of Lake Michigan, southwest Lake Erie, and southeastern Lake Ontario. We found strong relationships between the stress measures and characteristics of bird communities, fish communities, and water chemistry measurements from the coastal region. The stress measures are taken to represent the major threats to coastal ecosystems in the U.S. Great Lakes. Such regional-scale efforts are critical for understanding relationships between human disturbance and ecosystem response, and can be used to guide environmental decision-making at both regional and local scales.

Danz, Nicholas; Niemi, Gerald; Regal, Ronald (and others) [University of Minnesota Duluth, Duluth, MN (United States)

2007-05-15T23:59:59.000Z

334

Stress Actually Makes You Stronger ... At Least Some of the Time  

Office of Science (SC) Website

Stress Actually Makes You Stronger ... At Least Some of the Time News Featured Articles 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Presentations & Testimony...

335

Apparatuses for Pre-Stressing Specimens in Tension for In Situ ...  

hydrogen, coal-gasification-based hydrogen Patent Jy-An Wang, Ken Liu, and Zhili Feng, Apparatuses for Pre-stressing Rod-type Specimens in Tension

336

PROCESSED CALCITE PARTICLES IMPROVED LEAF PHOTOSYNTHESIS OF POTTED COT GRAPEVINES DURING WATER STRESS CONDITIONS.  

E-Print Network (OSTI)

Stress in the field? photosynthesis and growth. Ann. Bot.film applications can increase photosynthesis and water useleaves used for photosynthesis and chlorophyll fluorescence

ATTIA, Faouzi

2009-01-01T23:59:59.000Z

337

A proteomic analysis of drought and salt stress responsive proteins of different sorghum varieties.  

E-Print Network (OSTI)

?? This study reports on a proteomic analysis of sorghum proteomes in response to salt and hyperosmotic stresses. Two-dimensional gel electrophoresis (2DE) in combination with… (more)

Ngara, Rudo

2009-01-01T23:59:59.000Z

338

Thermal Stress and Reliability for Advanced Power Electronics and Electric Machines (Presentation)  

DOE Green Energy (OSTI)

This presentation gives an overview of NREL's Thermal Stress and Reliability Project work from October 2007 to March 2009 with an emphasis on activity during 2008/2009.

O'Keefe, M. P.

2009-05-01T23:59:59.000Z

339

Presentations | VIMSS - Virtual Institute for Microbial Stress and Survival  

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

Presenter Abstract All for go Presenter Abstract All for go Presentations Sort By Sort By ------------- Presenter: a-z Presenter: z-a Date: recent first Date: oldest first Select Funding Source Filter By Funding Source ---------------------- ESPP Metabolomics PCAP MAGGIE ERSP DS NASA EBI JBEI 327 presentations were found 1 Price, Morgan N. Reconstructing Metabolism by Comparative Genomics and Metabolite Analysis, 08/25/2008, Hildebrand Hall 320, Arkin Lab Meeting, [GroupMtgDvulAAAug08.pdf] Password Protected Abstract close The diversity of metabolism. Presenter Price, Morgan N. Funding Source Environmental Stress Pathway Project (ESPP) Keywords Bioinformatics, Comparative Genomics, Metabolomics 2 Joachimiak, Marcin P. Discovering and validating biological hypotheses from coherent patterns in functional genomics data, 08/12/2008, San Diego, CA, Society for Industrial Microbiology 2008 Annual Meeting, [MJoachimiak_SIM2008_final.pdf]

340

Irradiation-Induced Stress Corrosion Cracking of Austenitic Stainless  

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

Environmentally Assisted Environmentally Assisted Cracking of Ni-Base Alloys Capabilities Materials Testing Environmentally Assisted Cracking (EAC) of Reactor Materials Corrosion Performance/Metal Dusting Overview Light Water Reactors Fatigue Testing of Carbon Steels and Low-Alloy Steels Environmentally Assisted Cracking of Ni-Base Alloys Irradiation-Induced Stress Corrosion Cracking of Austenitic Stainless Steels Steam Generator Tube Integrity Program Air Oxidation Kinetics for Zr-based Alloys Fossil Energy Fusion Energy Metal Dusting Publications List Irradiated Materials Steam Generator Tube Integrity Other Facilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Corrosion and Mechanics of Materials Light Water Reactors Bookmark and Share

Note: This page contains sample records for the topic "von mises stress" 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

Mechanical Properties of Gels; Stress from Confined Fluids  

SciTech Connect

Abstract for Grant DE-FG02-97ER45642 Period: 1997-2002 Mechanical Properties of Gels 2002-2008 Stress from Confined Fluids Principal investigator: Prof. George W. Scherer Dept. Civil & Env. Eng./PRISM Eng. Quad. E-319 Princeton, NJ 08544 USA Recipient organization: Trustees of Princeton University 4 New South Princeton, NJ 08544 USA Abstract: The initial stage of this project, entitled Mechanical Properties of Gels, was dedicated to characterizing and explaining the properties of inorganic gels. Such materials, made by sol-gel processing, are of interest for fabrication of films, fibers, optical devices, advanced insulation and other uses. However, their poor mechanical properties are an impediment in some applications, so understanding the origin of these properties could lead to enhanced performance. Novel experimental methods were developed and applied to measure the stiffness and permeability of gels and aerogels. Numerical simulations were developed to reproduce the growth process of the gels, resulting in structures whose mechanical properties matched the measurements. The models showed that the gels are formed by the growth of relatively robust clusters of molecules that are joined by tenuous links whose compliance compromises the stiffness of the structure. Therefore, synthetic methods that enhance the links could significantly increase the rigidity of such gels. The next stage of the project focused on Stress from Confined Fluids. The first problem of interest was the enhanced thermal expansion coefficient of water that we measured in the nanometric pores of cement paste. This could have a deleterious effect on the resistance of concrete to rapid heating in fires, because the excessive thermal expansion of water in the pores of the concrete could lead to spalling and collapse. A series of experiments demonstrated that the expansion of water increases as the pore size decreases. To explain this behavior, we undertook a collaboration with Prof. Stephen Garofalini (Rutgers), who has developed the best simulations of water ever reported by use of molecular dynamics. Simulated heating of water in small pores provided quantitative agreement with experiments, and showed that the origin of the high expansion is the altered structure of water in the first two molecular layers adjacent to the pore wall. The final focus of the project was to understand the damage done by crystals growing in small pores. For example, the primary cause of damage to ancient monuments in the Mediterranean Basin is growth of salt crystals in the pores of the stone. Salt may enter stone as a result of capillary rise of groundwater, by leaching of mortar joints, deposition of marine spray, or reactions with atmospheric pollutants (such as oxides of nitrogen or sulfur). As the water evaporates, the salt solution becomes supersaturated and crystals precipitate. Stress results, because the salt usually repels the minerals in the pore walls. Our goal was to identify the factors contributing to the repulsion, so that we could develop a chemical treatment to reduce the repulsion and hence the stress. (We have recently demonstrated an effective treatment as part of a separately funded study.) In collaboration with Prof. Garofalini, molecular dynamics simulations have been done that correctly reproduce the structure of water around dissolved ions of sodium and chloride. We simulated the interaction between crystals of sodium chloride and quartz, and found that this particular system exhibits attractive forces, in agreement with experiment. The origin of the attraction is the orientation of dipolar water molecules near the surfaces of the crystals. Similar calculations now must be done in systems, such as potassium chloride and quartz, where the interaction is repulsive. This grant supported the education of two doctoral students, Hang-Shing Ma (Ph.D., 2002) and Melanie Webb (Ph.D. expected 2010), three post-doctoral researchers, Joachim Gross, Gudrun Reichenauer, and Shuangyan (Sonia) Xu, and five undergraduates (for senior theses or independent projects

George W. Scherer

2009-12-01T23:59:59.000Z

342

Gels under stress: the origins of delayed collapse  

E-Print Network (OSTI)

Attractive colloidal particles can form a disordered elastic solid or gel when quenched into a two-phase region, if the volume fraction is sufficiently large. When the interactions are comparable to thermal energies the stress-bearing network within the gel restructures over time as individual particle bonds break and reform. Typically, under gravity such weak gels show a prolonged period of either no or very slow settling, followed by a sudden and rapid collapse - a phenomenon known as delayed collapse. The link between local bond breaking events and the macroscopic process of delayed collapse is not well understood. Here we summarize the main features of delayed collapse and discuss the microscopic processes which cause it. We present a plausible model which connects the kinetics of bond breaking to gel collapse and test the model by exploring the effect of an applied external force on the stability of a gel.

Lisa J. Teece; James M. Hart; Kerry Yen Ni Hsu; Malcolm A. Faers; Paul Bartlett

2013-09-30T23:59:59.000Z

343

Cell Component Accelerated Stress Test Protocols for PEM Fuel Cells  

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

USCAR FUEL CELL TECH TEAM USCAR FUEL CELL TECH TEAM CELL COMPONENT ACCELERATED STRESS TEST PROTOCOLS FOR PEM FUEL CELLS (Electrocatalysts, Supports, Membranes, and Membrane Electrode Assemblies) Revised May 26, 2010 Fuel cells, especially for automotive propulsion, must operate over a wide range of operating and cyclic conditions. The desired operating range encompasses temperatures from below the freezing point to well above the boiling point of water, humidity from ambient to saturated, and half-cell potentials from 0 to >1.5 volts. Furthermore, the anode side of the cell may be exposed to hydrogen and air during different parts of the driving and startup/shutdown cycles. The severity in operating conditions is greatly exacerbated by the transient and cyclic nature of

344

Stress Corrosion Cracking Behavior of Cast Stainless Steels  

SciTech Connect

Casting of austenitic stainless steels offers the possibility of directly producing large and/or relatively complex structures, such as the first wall shield modules or the diverter cassette for the ITER fusion reactor. Casting offers major cost savings when compared to fabrication via welding of quarter modules machined from large forgings. However, the strength properties of such cast components are typically considered inferior to those of conventionally forged and annealed components. To improve and validate cast stainless steel as a substitute for wrought stainless steel, a development and testing program was initiated, utilizing nitrogen and manganese additions to promote improved performance. This paper focuses on the response of the first set of developmental alloys to neutron-irradiation and susceptibility to stress corrosion cracking. These cast materials may also have applications for different components in light water reactors. Results showed that all steels exhibited irradiation-induced hardening and a corresponding drop in ductility, as expected, although there is still considerable ductility in the irradiated samples. The cast steels all exhibited reduced hardening in comparison to a wrought reference steels, which may be related to a larger grain size. Higher nitrogen contents did not negatively influence irradiation performance. Regarding stress corrosion cracking susceptibility, the large difference in grain size limits the comparison between wrought and cast materials, and inclusions in a reference and archive cast alloy tests complicate analysis of these samples. Results suggest that the irradiated archive heat was more susceptible to cracking than the modified alloys, which may be related to the more complex microstructure. Further, the results suggest that the modified cast steel is at least as SCC resistant as wrought 316LN. The beneficial effect of nitrogen on the mechanical properties of the alloys remains after irradiation and is not detrimental to SCC resistance.

Teysseyre, Sebastien [University of Michigan; Busby, Jeremy T [ORNL; Was, Gary [University of Michigan

2009-01-01T23:59:59.000Z

345

Mean Stress and Environmental Effects on Fatigue in Type 304 Stainless Steel  

SciTech Connect

Fatigue life tests were performed in air on Type 304 stainless steel (304 SS) to establish the effect of mean stress under both load control and strain control. An apparent reduction of up to 26% in strain-amplitude occurred in the low and intermediate cycle regime (< 10{sup 8} cycles) for a mean stress of 138 Mpa. A quantitative description of mean stress effects using the Smith-Watson-Topper equivalent strain parameter was developed, which incorporates mean stress through the maximum stress. This description provided a tighter fit to the data, and allowed separation of mean stress and cold work effects. With this separation, the effect of mean stress was reduced to 12% decrease in strain amplitude at 138 Mpa. The stress-life curve apparently increased with increasing mean stress, due to the significant work hardening that occurred in tests with high mean stresses, especially under load control. Tests were performed on double-edge notched specimens of 304 SS in air and low oxygen water at 288 C. The elastically calculated increase in the notch tip stress accounted within 10% for the fatigue life reductions for a K{sub t} = 4.8 notch, but was 38% conservative for a K{sub t} = 8.8 notch. Fatigue crack initiation lives (defined as an 0.127 mm crack) in low oxygen water at 288 C were reduced by a factor of four to eight on cycles over those in air. Crack growth occurred throughout most of the fatigue ''initiation'' life. The increase in crack growth rate of 304 SS in water appears to be large enough to explain the reduced ''initiation'' life in this environment.

Kandra, J.T.; Leax, T.R.; Wire, G.L.

1999-04-01T23:59:59.000Z

346

Effect of grit blasting on the stress corrosion cracking behavior of line pipe steel  

SciTech Connect

The beneficial effect of grit blasting is demonstrated by experiments in which the threshold stress for SCC was determined for various blasting conditions. Although the introduction of compressive stresses, surface deformation and mill scale removal all contribute to the increase in SCC resistance, removal of mill scale on the surface had the most significant effect.

Koch, G.H.; Barlo, T.J.; Berry, W.E.

1984-10-01T23:59:59.000Z

347

Elastic sectional stress analysis of variable section piers subjected to three-dimensional loads  

Science Conference Proceedings (OSTI)

The elastic stress analysis of beam-column structures of uniaxial symmetrical variable cross-sections is developed using an extension of Euler-Bernoulli beam theory. The applied loads are general considering axial (P), flexure (M"x-M"y), shear (V"x-V"y), ... Keywords: Elastic sectional analysis, Shear stress, Tapered section, Three-dimensional loads, Variable section, Warping function

Lucian Stefan; Pierre Léger

2012-01-01T23:59:59.000Z

348

Private whispers/public eyes: Is receiving highly personal information in a public place stressful?  

Science Conference Proceedings (OSTI)

The use of technology to access personal information in public places is increasingly common, but can these interactions induce stress? Sixty-eight participants were led to believe that extremely sensitive personal information would be displayed via ... Keywords: Privacy, Public places, Stress, Technology

Linda Little; Pam Briggs

2009-08-01T23:59:59.000Z

349

Evanescent Pressure Gradient Response in the Upper Ocean to Subinertial Wind Stress Forcing of Finite Wavelength  

Science Conference Proceedings (OSTI)

The idea that Ekman transport driven by the mean synoptic wind stress on the f0-plane is a robust result is true only for infinite scale lengths of the wind stress forcing. For finite scale wavelengths [O(100 km)] and for a range of subinertial ...

Warren B. White; Gerard McNally

1987-07-01T23:59:59.000Z

350

Intercalation-Induced Stress and Heat Generation within Single Lithium-Ion Battery Cathode Particles  

E-Print Network (OSTI)

Intercalation-Induced Stress and Heat Generation within Single Lithium-Ion Battery Cathode sur- faces in postmortem analysis of batteries.5-7 Stress generation results from lithium-ion, as will be discussed later. Heat transfer analyses of lithium-ion batteries have stemmed from work on full cells.10

Sastry, Ann Marie

351

Computer attitude as a moderator in the relationship between computer anxiety, satisfaction, and stress  

Science Conference Proceedings (OSTI)

The present study empirically examines the relationship between computer anxiety, job satisfaction, career satisfaction, and stress. Based on self-efficacy theory and self-worth theory of achievement-motivation, it is hypothesized that the relationship ... Keywords: Attitude towards computers, Career satisfaction, Computer anxiety, Job satisfaction, Stress

Satyanarayana Parayitam; Kiran J. Desai; Mayur S. Desai; Mary K. Eason

2010-05-01T23:59:59.000Z

352

Volume fraction optimization of functionally graded composite panels for stress reduction and critical temperature  

Science Conference Proceedings (OSTI)

The volume fraction optimization of functionally graded (FG) composite panels is studied by considering stress reduction and thermo-mechanical buckling. The structure is made up of ceramic layer, functionally graded materials (FGMs) and metal layer. ... Keywords: 3-D finite element model, Functionally graded materials, Optimization, Stress reduction, Thermo-mechanical buckling

Kyung-Su Na; Ji-Hwan Kim

2009-09-01T23:59:59.000Z

353

A user-friendly tool for detecting the stress level in a person's daily life  

Science Conference Proceedings (OSTI)

Mental health care represents over a third of the cost of health care to all EU nations and, in USA, it is estimated to be around the 2.5% of the gross national product. Depression and Stress related disorders are the most common mental illnesses. The ... Keywords: depression, mental health, prevention, stress detection, usability

Irene Zaragozá; Beatriz Rey; Cristina Botella; Rosa Baños; Inés Moragrega; Diana Castilla; Mariano Alcañiz

2011-07-01T23:59:59.000Z

354

Evaluation of residual stress gradients in ductile cast iron using critical refracted longitudinal (Lcr) wave technique  

E-Print Network (OSTI)

Critically refracted longitudinal (LCR) waves have been investigated as a possible technique for the evaluation of the residual stress gradients present in ductile iron castings. Residual stresses are likely to develop in ductile cast iron during the cooling phase of a casting process. A LCR probe fabricated for previous research was used to make the velocity measurements. The samples investigated were of different modularity and two were annealed while one was not. The samples were milled at increments of approximately two millimeters and the LCR velocities were taken-at each increment. This provided data for the mapping of velocity versus depth which represents the residual stress gradient. To confirm the presence of the residual stress gradient, strain gages were attached to similar samples and the samples were saw cut with the intent to relieve residual stresses. The strain gages indicated that residual stresses were relieved by the sawcutting. The strain gage data was found to support the LCR velocity map to an extent. Both sets of data indicate compressive stresses on the surface. The data also allowed for an evaluation of the annealing procedure used. The results showed that even after full annealing remnant stresses are still present in the bars tested.

Pfluger, Ron Atlan

1995-01-01T23:59:59.000Z

355

Squeeze, rock, and roll; can tangible interaction with affective products support stress reduction?  

Science Conference Proceedings (OSTI)

Affective computing focuses on the interpretation of users emotions via physiological and behavioral inputs. Irrelevant gestures with a pen were found to increase when users were given a mentally demanding task. Accordingly, an embedded tangible interface ... Keywords: affective computing, haptic feedback, stress reduction, stressful behavior, tangible interaction

Miguel Bruns Alonso; David V. Keyson; Caroline C. M. Hummels

2008-02-01T23:59:59.000Z

356

A new wall-shear stress model for atmospheric boundary layer simulations  

Science Conference Proceedings (OSTI)

A new wall-shear stress model to be used as wall-boundary condition for Large Eddy Simulations of the Atmospheric Boundary Layer is proposed. The new model computes the wall shear stress and the vertical derivatives of the streamwise velocity ...

Marcus Hultmark; Marc Calaf; Marc B. Parlange

357

How Permeability Depends on Stress and Pore Pressure in Coalbeds: A New Model  

E-Print Network (OSTI)

, permeability is sensitive to changes in stress or pore pressure (i.e., changes in effective stress). This paper presents a new theoretical model for calculating pore volume (PV) compressibility and permeability in coals changes as pressure is decreased (i.e., draw- down). PV compressibility is derived in this theory from

358

Europe, Cutting Biofuel Subsidies, Redirects Aid to Stress Greenest Options -New York Times January 22, 2008  

E-Print Network (OSTI)

toward the annual target of biofuels making up 5.75 percent of transportation fuel. httpEurope, Cutting Biofuel Subsidies, Redirects Aid to Stress Greenest Options - New York Times January 22, 2008 Europe, Cutting Biofuel Subsidies, Redirects Aid to Stress Greenest Options By ELISABETH

359

Discontinuous surface cracks during stress corrosion cracking of stainless steel single crystal  

E-Print Network (OSTI)

Discontinuous surface cracks during stress corrosion cracking of stainless steel single crystal L Keywords: A. Stainless steel B. SEM C. Stress corrosion a b s t r a c t Single crystal 321 stainless steel, and the river-markings exhibited microshear facets along the {1 1 1} plane. Interaction between the main crack

Volinsky, Alex A.

360

Waterflood improvement in the Permian Basin: Impact of in-situ-stress evaluations  

SciTech Connect

The authors evaluated in-situ-stress magnitudes and directions to support waterflood improvement programs in McElroy field and North Westbrook Unit. In-situ-stress and hydraulic-fracture directions coincided with directional floodwater effects. This information contributed to successful waterflood realignment programs.

Nolen-Hoeksema, R.C.; Avasthi, J.M. (Chevron Petroleum Technology Co., Houston, TX (United States)); Pape, W.C. (West Australian Petroleum Pty. Ltd., Perth (Australia)); El Rabaa, A.W. (Mobil E and P Technical Center, Dallas, TX (United States))

1994-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

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

362

Strengthening, Crack Arrest And Multiple Cracking In Brittle Materials Using Residual Stresses.  

DOE Patents (OSTI)

Embodiments include a method for forming a glass which displays visible cracking prior to failure when subjected to predetermined stress level that is greater than a predetermined minimum stress level and less than a failure stress level. The method includes determining a critical flaw size in the glass and introducing a residual stress profile to the glass so that a plurality of visible cracks are formed prior to failure when the glass is subjected to a stress that is greater than the minimum stress level and lower than the critical stress. One method for forming the residual stress profile includes performing a first ion exchange so that a first plurality of ions of a first element in the glass are exchanged with a second plurality of ions of a second element that have a larger volume than the first ions. A second ion exchange is also performed so that a plurality of the second ions in the glass are exchanged back to ions of the first element.

Green, David J. (State College, PA); Sglavo, Vincenzo M. (Roncegno, IT); Tandon, Rajan (Fremont, CA)

2003-02-11T23:59:59.000Z

363

Residual stress stability in fiber textured stoichiometric AlN film grown using rf magnetron sputtering  

Science Conference Proceedings (OSTI)

The authors report on the stability of mechanical stress with aging and thermal cycling for columnar structured stoichiometric and homogeneous aluminum nitride thin films grown using radio frequency magnetron sputtering technique. The set of deposition parameters were optimized for the best possible orientation of crystallites in the c axis of compositionally stoichiometric films. The as-grown stress in the slightly nitrogen-rich film does not change when exposed to the atmosphere following deposition, while that in the nitrogen-deficient film, it changes due to oxidation. Additionally, the magnitude of as-grown stress has been found to depend on the substrate material in addition to the deposition parameters. The stress in the film grown on a Si(001) substrate was more tensile than in the film grown on a semi-insulating (si) GaAs(001) substrate for a given set of deposition parameters. Furthermore, the stress in the film grown on Si decreased with temperature, while that on si GaAs increased, indicating the thermally induced stress component to be the major component in the residual stress. Upon subsequent cooling the stress changes in both substrates followed the same path as of heating, thus exhibiting no hysteresis with thermal cycles between room temperature and 400 deg. C.

Sah, R. E.; Kirste, L.; Baeumler, M.; Hiesinger, P.; Cimalla, V.; Lebedev, V.; Baumann, H.; Zschau, H.-E. [Fraunhofer Institute for Applied Solid State Physics, Tullastrasse 72, 79108 Freiburg (Germany); Institut fuer Kernphysik, J. Goethe Universitaet, Max-von-Lauer-Str. 1, 60438 Frankfurt/M (Germany); DECHEMA e.V., Karl-Winnacker-Institut, Theodor-Heuss-Allee 25, 60486 Frankfurt/M (Germany)

2010-05-15T23:59:59.000Z

364

Clostridium thermocellum Transcriptomic Profiles after Exposure to Furfural or Heat Stress  

Science Conference Proceedings (OSTI)

Background The thermophilic anaerobe Clostridium thermocellum is a candidate consolidated bioprocessing (CBP)biocatalyst for cellulosic ethanol production. It is capable of both cellulose solubilization and its fermentation to produce lignocellulosic ethanol. Intolerance to stresses routinely encountered during industrial fermentations may hinder the commercial development of this organism. A previous C. thermocellum ethanol stress study showed that largest transcriptomic response was in genes and proteins related to nitrogen uptake and metabolism. Results In this study, C. thermocellum was grown to mid-exponential phase and treated with furfural or heat to a final concentration of 3 g.L-1 or 68 C respectively to investigate general and specific physiological and regulatory stress responses. Samples were taken at 10, 30, 60 and 120 min post-shock, and from untreated control fermentations, for transcriptomic analyses and fermentation product determinations and compared to a published dataset from an ethanol stress study. Urea uptake genes were induced following furfural stress, but not to the same extent as ethanol stress and transcription from these genes was largely unaffected by heat stress. The largest transcriptomic response to furfural stress was genes for sulfate transporter subunits and enzymes in the sulfate assimilatory pathway, although these genes were also affected late in the heat and ethanol stress responses. Lactate production was higher in furfural treated culture, although the lactate dehydrogenase gene was not differentially expressed under this condition. Other redox related genes such as a copy of the rex gene, a bifunctional acetaldehyde-CoA/alcohol dehydrogenase and adjacent genes did show lower expression after furfural stress compared to the control, heat and ethanol fermentation profiles. Heat stress induced expression from chaperone related genes and overlap was observed with the responses to the other stresses. This study suggests the involvement of C. thermocellum genes with functions in oxidative stress protection, electron transfer, detoxification, sulfur and nitrogen acquisition, and DNA repair mechanisms in its stress responses and the use of different regulatory networks to coordinate and control adaptation. Conclusions This study has identified C. thermocellum gene regulatory motifs and aspects of physiology and gene regulation for further study. The nexus between future systems biology studies and recently developed genetic tools for C. thermocellum offers the potential for more rapid strain development and for broader insights into this organism s physiology and regulation.

Wilson, Charlotte M [ORNL; Yang, Shihui [ORNL; Rodriguez, Jr., Miguel [ORNL; Ma, Qin [University of Georgia, Athens, GA; Johnson, Courtney M [ORNL; Dice, Lezlee T [ORNL; Xu, Ying [University of Georgia, Athens, GA; Brown, Steven D [ORNL

2013-01-01T23:59:59.000Z

365

CRUSTAL STRESS HETEROGENEITY IN THE VICINITY OF COSO GEOTHERMAL FIELD, CA |  

Open Energy Info (EERE)

CRUSTAL STRESS HETEROGENEITY IN THE VICINITY OF COSO GEOTHERMAL FIELD, CA CRUSTAL STRESS HETEROGENEITY IN THE VICINITY OF COSO GEOTHERMAL FIELD, CA Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: CRUSTAL STRESS HETEROGENEITY IN THE VICINITY OF COSO GEOTHERMAL FIELD, CA Details Activities (1) Areas (1) Regions (0) Abstract: Borehole induced structures in image logs of wells from the Coso Geothermal Field (CGF), CA record variation in the azimuth of principal stress. Image logs of these structures from five wells were analyzed to quantify the stress heterogeneity for three geologically distinct locations: two wells within the CGF (one in an actively produced volume), two on the margin of the CGF and outside the production area, and a control well several tens of kilometers south of the CGF. Average directions of

366

Fracture Permeability and In Situ Stress in the Dixie Valley, Nevada,  

Open Energy Info (EERE)

Fracture Permeability and In Situ Stress in the Dixie Valley, Nevada, Fracture Permeability and In Situ Stress in the Dixie Valley, Nevada, Geothermal Reservoir Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Fracture Permeability and In Situ Stress in the Dixie Valley, Nevada, Geothermal Reservoir Abstract Borehole televiewer, temperature and flowmeter logs and hydraulic fracturing stress measurements conducted in six wells penetrating a geothermal reservoir associated with the Stillwater fault zone in Dixie Valley, Nevada, were used to investigate the relationship between reservoir permeability and the contemporary in situ stress field. Data from wells drilled into productive and nonproductive segments of the Stillwater fault zone indicate that permeability in all wells is dominated by a relatively

367

IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO  

Open Energy Info (EERE)

IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO GEOTHERMAL FIELD Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF THE COSO GEOTHERMAL FIELD Details Activities (1) Areas (1) Regions (0) Abstract: High rock temperatures, a high degree of fracturing, high tectonic stresses, and low permeability are the combination of qualities that define an ideal candidate-Enhanced Geothermal System (EGS) reservoir. The Coso Geothermal Field is an area where fluid temperatures exceeding 300°C have been measured at depths less than 10,000 feet and the reservoir is both highly fractured and tectonically stressed. Some of the wells within this portion of the reservoir are relatively impermeable,

368

Stress and Fluid-Flow Interaction for the Coso Geothermal Field Derived  

Open Energy Info (EERE)

Stress and Fluid-Flow Interaction for the Coso Geothermal Field Derived Stress and Fluid-Flow Interaction for the Coso Geothermal Field Derived from 3D Numerical Models Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Stress and Fluid-Flow Interaction for the Coso Geothermal Field Derived from 3D Numerical Models Details Activities (1) Areas (1) Regions (0) Abstract: The efficiency of geothermal energy production at the Coso Geothermal Field in eastern California is reliant on the knowledge of fluid flow directions associated with fracture networks. We use finite element analysis to establish the 3D state of stress within the tectonic setting of the Coso Range. The mean and differential stress distributions are used to infer fluid flow vectors and second order fracture likelihood and orientation. The results show that the Coso Range and adjacent areas are

369

Structure, tectonics and stress field of the Coso Range, Inyo County,  

Open Energy Info (EERE)

tectonics and stress field of the Coso Range, Inyo County, tectonics and stress field of the Coso Range, Inyo County, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Structure, tectonics and stress field of the Coso Range, Inyo County, California Details Activities (1) Areas (1) Regions (0) Abstract: The tectonics of the Coso Range has been described as having arcuate and ring faults both suggesting the presence of a circumscribed subsidence bowl or calderalike feature. New information suggests the Coso Range is situated in an area of transition between the stress of the right slip San Andreas fault-plate interaction and the extensional tectonics of the Basin and Range. Arcuate faults in the Coso Range are interpreted to have been produced by the regional stress field rather than to have been of

370

High-Energy X-ray Diffraction Study of Internal Stresses in Metal Matrix  

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High-Energy X-ray Diffraction Study of Internal Stresses in Metal Matrix High-Energy X-ray Diffraction Study of Internal Stresses in Metal Matrix Composites Metal matrix composites (MMCs) comprise an intriguing new class of materials coming to prominence in the aerospace, electronics, and automotive industries. Internal stresses play an important role in the behavior and successful application of MMCs and multi-phase alloys. These stresses form during processing and service due to transformation or thermal expansion mismatch, as well as elastic and plastic mismatch during deformation. In order to develop a deeper understanding of the thermo-mechanical behavior of these materials, it is of key interest to examine the development of mean stresses in the phases of the composite as a function of time upon changes of temperature and/or external load.

371

A Model For Stress-Controlled Pipe Growth | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » A Model For Stress-Controlled Pipe Growth Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Model For Stress-Controlled Pipe Growth Details Activities (0) Areas (0) Regions (0) Abstract: The rock mechanics theory for deformation of underground mining excavations under high stress conditions can be used to explain the growth and geometry of volcanic pipes. In an underground excavation stress concentrates greatest on the sides of an excavation perpendicular to the principal vector of compression. If the stress is high enough fractures will develop causing scaling of the tunnel sidewalls and tunnel growth

372

Neutron diffraction measurements of residual stresses in friction stir welding: a review  

Science Conference Proceedings (OSTI)

Significant amounts of residual stresses are often generated during welding and result in critical degradation of the structural integrity and performance of components. Neutron diffraction has become a well established technique for the determination of residual stresses in welds because of the unique deep penetration, three-dimensional mapping capability, and volume averaged bulk measurements characteristic of the scattering neutron beam. Friction stir welding has gained prominence in recent years. The authors reviewed a number of neutron diffraction measurements of residual stresses in friction stir welds and highlighted examples addressing how the microstructures and residual stresses are correlated with each other. An example of in situ neutron diffraction measurement result shows the evolution of the residual stresses during welding.

Woo, Wan Chuck [ORNL; Feng, Zhili [ORNL; Wang, Xun-Li [ORNL; David, Stan A [ORNL

2011-01-01T23:59:59.000Z

373

Multifractal analysis of stress time series during ultrathin lubricant film melting  

E-Print Network (OSTI)

Melting of an ultrathin lubricant film confined between two atomically flat surfaces is we studied using the rheological model for viscoelastic matter approximation. Phase diagram with domains, corresponding to sliding, dry, and two types of $stick-slip$ friction regimes has been built taking into account additive noises of stress, strain, and temperature of the lubricant. The stress time series have been obtained for all regimes of friction using the Stratonovich interpretation. It has been shown that self-similar regime of lubricant melting is observed when intensity of temperature noise is much larger than intensities of strain and stress noises. This regime is defined by homogenous distribution, at which characteristic stress scale is absent. We study stress time series obtained for all friction regimes using multifractal detrended fluctuation analysis. It has been shown that multifractality of these series is caused by different correlations that are present in the system and also by a power-law distribu...

Khomenko, A V; Borisyuk, V N; 10.1142/S0219477510000046

2010-01-01T23:59:59.000Z

374

The effect of crack growth stability induced by residual compressive stresses on strength variability  

Science Conference Proceedings (OSTI)

Rising {ital T}- (or {ital R}-) curve behavior is increasingly being used in order to improve the mechanical reliability of ceramic materials. In this study, the possibility of inducing such behavior using residual compressive stresses is analyzed. The {ital T}-curves obtained for certain residual stress profiles induce crack stability when the stress minima (compressive stress maxima) lie away from the surface of the sample. The consequences of this stabilization on the strength characteristics are a significant reduction in the strength variability and strength insensitivity to the initial flaw size. In addition to these desirable features, considerable strengthening is also obtained. Hence, suitably engineered compressive stress profiles are shown to be a novel and alternative means of enhancing mechanical reliability.

Tandon, R.; Green, D.J. (Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States))

1992-03-01T23:59:59.000Z

375

Reducing stress in sheep by feeding the seaweed Ascophyllum nodosum  

E-Print Network (OSTI)

Feeding the extract of the seaweed Ascophyllum nodosum (ANOD) has been shown to mediate the response of livestock to certain environmental stressors. To determine if feeding ANOD is useful in alleviating handling and transport stress, two trials were conducted. The dose response trial was conducted to determine at which rate ANOD should be fed to obtain beneficial results. Forty-four lambs received ANOD at either 0 (control), 0.5, 1, or 2% of dry matter intake per day (approximately 0, 0.25, 0.5, and 1 g/kg of body wt per day). Sheep were administered ANOD twice daily for 14d. After 14d of supplementation, IgG and IgM antibody response to ovalbumin was reduced by ANOD. The sheep fed at the 2% rate had a narrower range of body temperature during transport than controls. The 2% rate also had lower body temperatures than the controls during times when the thermal heat index was above 80. The sheep fed the 2% rate had lower cortisol and aldosterone concentrations during walking and transport compared to the controls. Post transport, sheep supplemented at the 1 or 2% rates were less dehydrated as indicated by plasma chemistry profiles andelectrolyte concentrations. In a subsequent trial, the major components of the ANOD (fucoidan, salt, and betaine) were fed to determine which, if any, were responsible for the treatment effects in the dose response trial. After 14d supplementation, the salt and ANOD sheep had a depressed IgG and IgM antibody response to ovalbumin and an increase in white blood cell counts and lymphocyte numbers compared to controls. The ANOD sheep were generally lower in body temperature than the other treatments during transport. The ANOD and salt sheep had lower cortisol concentrations compared to controls. At the end of transport, sheep supplemented with ANOD or salt had lower electrolyte concentrations than control sheep. Supplementation with ANOD was associated with lowered body temperature; however, it also suppressed antibody titer which could leave animals susceptible to bacterial infection. The lowered antibody production is of concern and needs further study before ANOD can be recommended as a useful stress management tool.

Archer, Gregory Scott

2005-08-01T23:59:59.000Z

376

Physiological indicators of tick-induced stress in grazing  

E-Print Network (OSTI)

Three studies utilizing a single group of growing beef steers were conducted to ascertain the effects of tick stress on cattle and to evaluate the use of bio-forensic techniques of detection. Steers (n = 28, 194 ± 3.0 kg) were randomly assigned to one of four treatments in a 2 x 2 factorial arrangement: moderate (14.0 ± 1.0% CP, 60 ± 1.5% TDN) versus low (7.0 ± 1.0% CP, 58 ± 1.5% TDN) plane of nutrition, and control (no tick) versus tick treatment (300 pair of adult (Amblyomma americanum) per treated animal). Steers were individually fed experimental diets ad libitum for 35 days prior to and 21 days following the start of tick infestation (day 0), with peak tick feeding occurring 10 to 14 days post tick infestation. In study 1, blood was sampled on day -7, 0, 7, 8, 9, 10, 11, 13, 17 and 21, and plasma analyzed for metabolic and endocrine indicators. Within the low plane of nutrition, IGF-1 (ng/ml) was greater in control (P < 0.05) than in the tick treated (139.57 ± 9.3 vs 111.4 ± 9.3) group. Within the moderate plane of nutrition, tick treated cattle had higher (P < 0.05) plasma cortisol than nontreated. In study 2, fecal samples were analyzed for metabolic, endocrine and immunologic indicators. Fecal cortisol was the only constituent measured that was affected by treatment and not by plane of nutrition. The highest average daily fecal cortisol observed was for day 13, during peak tick feeding and after six days of repeated blood sampling. In study 3, near infrared spectra were obtained in the 1100-2498 nm range. Spectra were assembled into groups by plane of nutrition, treatment, and by plane of nutrition by treatment. Periods of 7 ± 1 days correspond to significant delineations in the tick feeding cycle. There were differences in pre-infestation versus infestation fecal spectra within the tick treated groups in both the moderate and low planes of nutrition. These differences can not be wholly attributed to tick treatment, but may have also been affected by blood sampling stress.

Tolleson, Douglas Ray

2007-12-01T23:59:59.000Z

377

A Method for Imposing Surface Stress and Heat Flux Conditions in Finite-Difference Models with Steep Terrain  

Science Conference Proceedings (OSTI)

A numerical implementation of the surface stress boundary condition is presented for finite-difference models in which the terrain slope and curvature cannot necessarily be considered small. The method involves reducing the discretized stress ...

C. C. Epifanio

2007-03-01T23:59:59.000Z

378

The Steady-State Barotropic Response of the Gulf of Maine and Adjacent Regions to Surface Wind Stress  

Science Conference Proceedings (OSTI)

The response of the Gulf of Maine region to steady, spatially uniform wind stress is examined using a linearized numerical model, with the influence of the strong tidal currents in the region included in the bottom stress formulation. The ...

Daniel G. Wright; David A. Greenberg; John W. Loder; Peter C. Smith

1986-05-01T23:59:59.000Z

379

Reprogramming of tRNA modifications controls the oxidative stress response by codon-biased translation of proteins  

E-Print Network (OSTI)

Selective translation of survival proteins is an important facet of the cellular stress response. We recently demonstrated that this translational control involves a stress-specific reprogramming of modified ribonucleosides ...

Chan, Clement T. Y.

380

Evaluation of CMIP3 and CMIP5 Wind Stress Climatology Using Satellite Measurements and Atmospheric Reanalysis Products  

Science Conference Proceedings (OSTI)

Wind stress measurements from the Quick Scatterometer (QuikSCAT) satellite and two atmospheric reanalysis products are used to evaluate the annual mean and seasonal cycle of wind stress simulated by phases 3 and 5 of the Coupled Model ...

Tong Lee; Duane E. Waliser; Jui-Lin F. Li; Felix W. Landerer; Michelle M. Gierach

2013-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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381

Molecular stress response in the CNS of mice after systemic exposure to interferon-alpha, ionizing radiation and ketamine  

E-Print Network (OSTI)

Lowe et al. , 2008 MOLECULAR STRESS RESPONSE IN THE CNS OFXRLowe@lbl.gov Keywords: molecular-response, troponin T1,1 expression may be an early molecular biomarker of stress

Lowe, Xiu R.

2009-01-01T23:59:59.000Z

382

Step-Stress Accelerated Degradation Testing for Solar Reflectors: Preprint  

DOE Green Energy (OSTI)

To meet the challenge to reduce the cost of electricity generated with concentrating solar power (CSP) new low-cost reflector materials are being developed including metalized polymer reflectors and must be tested and validated against appropriate failure mechanisms. We explore the application of testing methods and statistical inference techniques for quantifying estimates and improving lifetimes of concentrating solar power (CSP) reflectors associated with failure mechanisms initiated by exposure to the ultraviolet (UV) part of the solar spectrum. In general, a suite of durability and reliability tests are available for testing a variety of failure mechanisms where the results of a set are required to understand overall lifetime of a CSP reflector. We will focus on the use of the Ultra-Accelerated Weathering System (UAWS) as a testing device for assessing various degradation patterns attributable to accelerated UV exposure. Depending on number of samples, test conditions, degradation and failure patterns, test results may be used to derive insight into failure mechanisms, associated physical parameters, lifetimes and uncertainties. In the most complicated case warranting advanced planning and statistical inference, step-stress accelerated degradation (SSADT) methods may be applied.

Jones, W.; Elmore, R.; Lee, J.; Kennedy, C.

2011-09-01T23:59:59.000Z

383

HammerCloud: A Stress Testing System for Distributed Analysis  

E-Print Network (OSTI)

Distributed analysis of LHC data is an I/O-intensive activity which places large demands on the internal network, storage, and local disks at remote computing facilities. Commissioning and maintaining a site to provide an efficient distributed analysis service is therefore a challenge which can be aided by tools to help evaluate a variety of infrastructure designs and configurations. HammerCloud (HC) is one such tool; it is a stress testing service which is used by central operations teams, regional coordinators, and local site admins to (a) submit arbitrary number of analysis jobs to a number of sites, (b) maintain at a steady-state a predefined number of jobs running at the sites under test, (c) produce web-based reports summarizing the efficiency and performance of the sites under test, and (d) present a web-interface for historical test results to both evaluate progress and compare sites. HC was built around the distributed analysis framework Ganga, exploiting its API for grid job management. HC has been ...

van der Ster, Daniel C; Ubeda Garcia, Mario; Paladin, Massimo

2011-01-01T23:59:59.000Z

384

Program on Technology Innovation: An Evaluation of Surface Stress Improvement Technologies for PWSCC Mitigation of Alloy 600 Nuclear Components  

Science Conference Proceedings (OSTI)

This report documents the progress for 2005 on a new project to evaluate surface stress improvement methods to mitigate the initiation of PWSCC in Alloy 600 nuclear plant components. The first potential application for these various surface stress improvement technologies for SCC mitigation in PWR Alloy 600 components was identified as the bottom mounted nozzle (BMN). Mitigation will be demonstrated by creating both sufficient compressive surface stress and depth of the compressive stress on the ID and O...

2006-03-31T23:59:59.000Z

385

Materials Reliability Program: Validation of Welding Residual Stress Models for PWR Piping Dissimilar Metal Welds (MRP-271)  

Science Conference Proceedings (OSTI)

The residual stresses imparted by the welding process are a principal factor in primary water stress corrosion cracking (PWSCC) of Dissimilar Metal (DM) piping butt welds in PWRs. Analytical models are frequently used to simulate the welding process in order to predict the residual stress distribution in the weld and base material as an input to crack growth calculations. The crack growth calculations have demonstrated a high sensitivity to the welding residual stress distribution inputs. As part of the ...

2009-12-22T23:59:59.000Z

386

BILAM: a composite laminate failure-analysis code using bilinear stress-strain approximations  

DOE Green Energy (OSTI)

The BILAM code which uses constant strain laminate analysis to generate in-plane load/deformation or stress/strain history of composite laminates to the point of laminate failure is described. The program uses bilinear stress-strain curves to model layer stress-strain behavior. Composite laminates are used for flywheels. The use of this computer code will help to develop data on the behavior of fiber composite materials which can be used by flywheel designers. In this program the stress-strain curves are modelled by assuming linear response in axial tension while using bilinear approximations (2 linear segments) for stress-strain response to axial compressive, transverse tensile, transverse compressive and axial shear loadings. It should be noted that the program attempts to empirically simulate the effects of the phenomena which cause nonlinear stress-strain behavior, instead of mathematically modelling the micromechanics involved. This code, therefore, performs a bilinear laminate analysis, and, in conjunction with several user-defined failure interaction criteria, is designed to provide sequential information on all layer failures up to and including the first fiber failure. The modus operandi is described. Code BILAM can be used to: predict the load-deformation/stress-strain behavior of a composite laminate subjected to a given combination of in-plane loads, and make analytical predictions of laminate strength.

McLaughlin, P.V. Jr.; Dasgupta, A.; Chun, Y.W.

1980-10-01T23:59:59.000Z

387

Stress studies in EFG. Quarterly progress report, October 1-December 31, 1983  

DOE Green Energy (OSTI)

Stress analysis at Harvard University has examined the implication of non-zero interface stresses on model predictions. Stress distributions at distances greater than about 1 mm from the interface are shown to be independent of the interface stress at high creep intensities, and the predictions based on zero initial stress can be used with confidence. Numerical models for growth dynamics developed at MIT are compared with experimental data on t-V relationships and on interface shape obtained from impurity redistribution in aluminum-doped 10 cm wide ribbon. Comparison of primary creep responses in FZ (floating zone) and CZ (Czochralski) silicon above 1200/sup 0/C using four-point bending indicates that oxygen has a significant influence on the creep rate. Both the strain rate and resulting dislocation densities generated in FZ silicon are an order of magnitude higher than for the CZ material at comparable applied stress levels. A fiber optics probe suitable for temperature measurement during sheet growth has been constructed and tested. Study of the feasibility of using laser interferometric techniques for residual stress measurements has continued at the University of Illinois. The method has been successfully applied to CZ silicon, and is being evaluated for use with EFG ribbon.

Kalejs, J.P.

1984-02-15T23:59:59.000Z

388

Stage 1 behavior in a stress corrosion study of Type 304 stainless steel  

SciTech Connect

In stress corrosion studies, crack velocity plotted with respect to stress intensity generally yields a characteristic curve with three distinct regions. Stage I exhibits a threshold (K{sub ISCC}) followed by a rapid increase in crack velocity (da/dt) for small changes in stress intensity. Stage II is characterized by an essentially constant crack velocity with increases in the stress intensity. Stage III exhibits a rapid increase in crack velocity for small increases in stress intensity leading to fracture. Stage I behavior has been poorly characterized in literature due to previous emphasis on determining the threshold K{sub ISCC} and difficulty and uncertainty in measuring of a large increase in crack velocity with only incremental changes in stress intensity. Tests were conducted in the stage I regime to measure crack velocity as a function of constant stress intensity. Constant K specimens were prepared according to the Mostovoy design, (a tapered double cantilever beam). Specimens were prepared from Type 304 stainless steel containing 0.06 wt% C solution annealed at 1100C for 1 hour, water quenched, and annealed at 625C for 24 hours to produce sensitization. A sodium thiosulfate solution at 50{degree}C was chosen as the test environment.

Lund, A.L. [Washington State Univ., Richland, WA (United States); Jones, R.H. [Pacific Northwest Lab., Richland, WA (United States)

1994-03-01T23:59:59.000Z

389

Origin of stress in radio frequency magnetron sputtered zinc oxide thin films  

SciTech Connect

Highly c-axis oriented ZnO thin films have been deposited on silicon substrates by planar rf magnetron sputtering under varying pressure (10-50 mTorr) and oxygen percentage (50-100%) in the reactive gas (Ar + O{sub 2}) mixture. The as-grown films were found to be stressed over a wide range from -1 x 10{sup 11} to -2 x 10{sup 8} dyne/cm{sup 2} that in turn depends strongly on the processing conditions, and the film becomes stress free at a unique combination of sputtering pressure and reactive gas composition. Raman spectroscopy and photoluminescence (PL) analyses identified the origin of stress as lattice distortion due to defects introduced in the ZnO thin film. FTIR study reveals that Zn-O bond becomes stronger with the increase in oxygen fraction in the reactive gas mixture. The lattice distortion or stress depends on the type of defects introduced during deposition. PL spectra show the formation of a shoulder in band emission with an increase in the processing pressure and are related to the presence of stress. The ratio of band emission to defect emission decreases with the increase in oxygen percentage from 50 to 100%. The studies show a correlation of stress with the structural, vibrational, and photoluminescence properties of the ZnO thin film. The systematic study of the stress will help in the fabrication of efficient devices based on ZnO film.

Menon, Rashmi; Gupta, Vinay; Sreenivas, K. [Electronic Material and Devices Laboratory, Department of Physics and Astrophysics, University of Delhi, Delhi 11007 (India); Tan, H. H.; Jagadish, C. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)

2011-03-15T23:59:59.000Z

390

Measurement of in-situ stress in salt and rock using NQR techniques  

Science Conference Proceedings (OSTI)

A discussion of how stress and strain affect the quantities which can be measured in an NQR experiment shows that, for stresses of the magnitude to be expected at depths up to about 10,000 feet, quadrupole coupling constants will fall in the range of 1 to 10 kHz for both the sodium and chloride ions in NaCl. The most promising system involves pulsed nuclear double resonance detection; and alterative is to observe the quadrupolar splitting of the NMR signal. Choices to be made in the measurement and mapping techniques are discussed. The well-known perturbation of the homogenous stress field in the neighborhood of a borehole is shown to be advantageous from the point of view of obtaining directional information on the stress. Construction and operation of a borehole stress sensor are considered. The NQR technique seems feasible for measuring the magnitude and direction of underground stress with a resolution of about 25 psi, or 2.5% at 1000 psi. Downhole instrumentation suitable for in-situ determinations of stress appears within the state of the art. Additional tasks required on the project are identified.

Schempp, E.; Hirschfeld, T.; Klainer, S.

1980-12-01T23:59:59.000Z

391

Assessment of Cracks in Stress Concentration Regions with Localized Plastic Zones  

SciTech Connect

Marty brittle fracture evaluation procedures include plasticity corrections to elastically computed stress intensity factors. These corrections, which are based on the existence of a plastic zone in the vicinity of the crack tip, can overestimate the plasticity effect for a crack embedded in a stress concentration region in which the elastically computed stress exceeds the yield strength of the material in a localized zone. The interactions between the crack, which acts to relieve the high stresses driving the crack, plasticity effects in the stress concentration region, and the nature and source of the loading are examined by formulating explicit flaw finite element models for a crack emanating from the root of a notch located in a panel subject to an applied tensile stress. The results of these calculations provide conditions under which a crack-tip plasticity correction based on the Irwin plastic zone size overestimates the plasticity effect. A failure assessment diagram (FAD) curve is used to characterize the effect of plasticity on the crack driving force and to define a less restrictive plasticity correction for cracks at notch roots when load-controlled boundary conditions are imposed. The explicit flaw finite element results also demonstrate that stress intensity factors associated with load-controlled boundary conditions, such as those inherent in the ASME Boiler and Pressure Vessel Code as well as in most handbooks of stress intensity factors, can be much higher than those associated with displacement-controlled conditions, such as those that produce residual or thermal stresses. Under certain conditions, the inclusion of plasticity effects for cracks loaded by displacement-controlled boundary conditions reduces the crack driving force thus justifying the elimination of a plasticity correction for such loadings. The results of this study form the basis for removing unnecessary conservatism from flaw evaluation procedures that utilize plasticity corrections.

Friedman, E.

1998-11-25T23:59:59.000Z

392

Correlations to determine in-situ stress from open-hole logging data in sandstone reservoirs  

E-Print Network (OSTI)

Knowledge of in-situ stress distribution within reservoir sandstones and the surrounding formations is recognized as one of the most important factors in the design and analysis of hydraulic fractures. In-situ stress contrast between layers of rock ultimately controls the vertical fracture growth and, thus, directly affects fracture length and width. A new correlation model has been developed for estimating in-situ stress distribution within different interlayers. The method correlates values of minimum principal in-situ stress derived from both open-hole log data and cased-hole stress tests and gamma ray readings. The information used during this research project came from the Gas Research Institute (GRI's) Staged Field Experiment (SFE) No. I and No.2 wells. The new parameter correlation developed in this research has been applied to the Travis Peak Formation in East Texas. The advantages of the new correlation are (1) for a routine application, the correlations provide the most useful source of in-situ stress determination in the Travis Peak Formation, (2) the effect of shale has been considered in the correlation model, and (3) the model is easy to use once the lithology of the layer has been identified. This new model can be used to estimate in-situ stress distribution from logs and cores. However, it is important that these estimates be calibrated with actual field measurements of in-situ stress. Once the model correlation model has been calibrated, the petroleum engineer can reduce the cost of developing data sets for conducted reservoir studies by using only logs to estimate the in-situ stress profile.

Gongora, Cesar Augusto

1995-01-01T23:59:59.000Z

393

Evaluation of plant seedling water stress using dynamic fluorescence index with blue LED-based fluorescence imaging  

Science Conference Proceedings (OSTI)

A dynamic fluorescence image index system capable of non-destructive assessment of water stress in cabbage seedlings was developed. The quenching curves of chlorophyll fluorescence characteristic to the plant's water stress status under reduced excitation ... Keywords: Chlorophyll fluorescence, Fluorescence image, Fluorescence index, Water stress

Shih-Chieh Hsiao; Suming Chen; I-Chang Yang; Chia-Tseng Chen; Chao-Yin Tsai; Yung-Kun Chuang; Feng-Jehng Wang; Yu-Liang Chen; Tzong-Shyan Lin; Y. Martin Lo

2010-07-01T23:59:59.000Z

394

ENERGY CHANGES IN STRESSED BODIES DUE TO VOID AND CRACK J. R. Rice** and D. C. Drucker***  

E-Print Network (OSTI)

, and the mechanical aspects of stress corrosion cracking are discussed. INTRODUCTION A comparison is made firstENERGY CHANGES IN STRESSED BODIES DUE TO VOID AND CRACK GROWTH* J. R. Rice** and D. C. Drucker materials, and for the mechanical aspects of stress corrosion. The authors acknowledge with thei~ respective

395

High-spatial-resolution Raman microscopy of stress in shallow-trench-isolated Si structures  

Science Conference Proceedings (OSTI)

Stress in single and periodic shallow-trench-isolated Si structures was examined by 364 nm excitation confocal resonance Raman microscopy, laser penetration being restricted to the near-surface region. Using a 1.3 numerical aperture microobjective lens with a theoretical {approx}140 nm spatial resolution, the authors show that the configuration with both incident and scattered lights polarized parallel to each other and perpendicular to Si stripes is favorable for stress detection in the middle of the stripes, suppressing contributions from their edges. The stresses located in different areas of the structures were identified and analyzed.

Poborchii, Vladimir; Tada, Tetsuya; Kanayama, Toshihiko [MIRAI, Advanced Semiconductor Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 4, Higashi, Tsukuba 305-8562 (Japan)

2006-12-04T23:59:59.000Z

396

Stress transmission and isostatic states of non-rigid particulate systems  

E-Print Network (OSTI)

The isostaticity theory for stress transmission in macroscopic planar particulate assemblies is extended here to non-rigid particles. It is shown that, provided that the mean coordination number in $d$ dimensions is $d+1$, macroscopic systems can be mapped onto equivalent assemblies of perectly rigid particles that support the same stress field. The error in the stress field that the compliance introduces for finite systems is shown to decay with size as a power law. This leads to the conclusion that the isostatic state is not limited to infinitely rigid particles both in two and in three dimensions, and paves the way to an application of isostaticity theory to more general systems.

Raphael Blumenfeld

2005-01-28T23:59:59.000Z

397

2012 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 20-25, 2012  

SciTech Connect

The Gordon Research Conference on MICROBIAL STRESS RESPONSE was held at Mount Holyoke College, South Hadley, Massachusetts, July 15-20, 2012. The Conference was well-attended with 180 participants. The 2012 Microbial Stress Responses Gordon Research Conference will provide a forum for the open reporting of recent discoveries on the diverse mechanisms employed by microbes to respond to stress. Approaches range from analysis at the molecular level (how are signals perceived and transmitted to change gene expression or function) to cellular and microbial community responses. Gordon Research Conferences does not permit publication of meeting proceedings.

Timothy Donohue

2012-07-25T23:59:59.000Z

398

Method for measuring residual stresses in materials by plastically deforming the material and interference pattern comparison  

DOE Patents (OSTI)

A method for measuring residual stress in a material comprising the steps of establishing a speckle pattern on the surface with a first laser then heating a portion of that pattern with an infrared laser until the surface plastically deforms. Comparing the speckle patterns before and after deformation by subtracting one pattern from the other will produce a fringe pattern that serves as a visual and quantitative indication of the degree to which the plasticized surface responded to the stress dung heating and enables calculation of the stress.

Pechersky, Martin J. (241 Chardonnat La., Aiken, SC 29803)

1995-01-01T23:59:59.000Z

399

In situ stress, fracture, and fluid flow analysis in Well 38C-9: an  

Open Energy Info (EERE)

In situ stress, fracture, and fluid flow analysis in Well 38C-9: an In situ stress, fracture, and fluid flow analysis in Well 38C-9: an enhanced geothermal system in the Coso geothermal field Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: In situ stress, fracture, and fluid flow analysis in Well 38C-9: an enhanced geothermal system in the Coso geothermal field Abstract Geoscientists from the Coso Operating Company, EGI-Utah, GeoMechanics International, and the U.S. Geological Survey are cooperating in a multi-year study to develop an Enhanced Geothermal System (EGS) in the Coso Geothermal Field. Key to the creation of an EGS is an understanding of the relationship among natural fracture distribution, fluid flow, and the ambient tectonic stresses that exist within the resource in order to design

400

As OPEC Ministers Meet, Secretary Chu Stresses the Importance of Energy  

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

As OPEC Ministers Meet, Secretary Chu Stresses the Importance of As OPEC Ministers Meet, Secretary Chu Stresses the Importance of Energy Independence As OPEC Ministers Meet, Secretary Chu Stresses the Importance of Energy Independence March 15, 2009 - 12:00am Addthis Washington, DC - As OPEC ministers held a meeting in Vienna Sunday, U.S. Energy Secretary Steven Chu again stressed the need for energy independence and called for global cooperation on energy, economic and climate challenges. "While OPEC's actions are just one factor among many that go into the market price of oil, I'm pleased that there won't be further production cuts -- which could help to avoid oil price volatility," Secretary Chu said. "However, I continue to believe that we should stay focused on what our country can do to become energy independent -- ending our dependence on

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While these samples are representative of the content of NLEBeta,
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401

Science and Cellular Stresses | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Science and Science and Cellular Stresses News Featured Articles 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Presentations & Testimony News Archives Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 12.21.11 Science and Cellular Stresses Research reveals new insights into tumor suppression. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo p53 tumor suppressor Protein Databank The holiday season can be stressful with its just-missed parking spots and perfectly horrible holiday sweaters. And spending time bonding with family and friends can be a great way to relieve those stresses (while perhaps causing others!). In a sense, cells studied by the Office of Science's Brookhaven National

402

P wave anisotropy, stress, and crack distribution at Coso geothermal field,  

Open Energy Info (EERE)

wave anisotropy, stress, and crack distribution at Coso geothermal field, wave anisotropy, stress, and crack distribution at Coso geothermal field, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: P wave anisotropy, stress, and crack distribution at Coso geothermal field, California Details Activities (1) Areas (1) Regions (0) Abstract: A new inversion method for P wave anisotropy (Wu and Lees, 1999a) has been applied to high-precision, microseismic traveltime data collected at Coso geothermal region, California. Direction-dependent P wave velocity and thus its perturbation, are represented by a symmetric positive definite matrix A instead of a scalar. The resulting anisotropy distribution is used to estimate variations in crack density, stress distribution and permeability within the producing geothermal field. A circular dome-like

403

Effects of modeled terms in the Reynolds-stress transport equations  

DOE Green Energy (OSTI)

A discussion of the origins and interpretation of various previously proposed models for the terms in the incompressible Reynolds-stress equation is given. It is hoped that the interpretations will provoke thoughts that will help in the future modeling of Reynolds-stress transport equations. Different forms of the closed Reynolds-stress equation have been solved numerically for the given mean velocity field of the wake flow behind a flat plate at a Reynolds number of 1000. A finite-difference/finite-volume collocation scheme was used to approximate the spatial derivatives, which were implemented in a time-marching scheme. The numerical time integration produced values for the six independent Reynolds-stress components, the turbulent kinetic energy decay rate, and the turbulent length scale for each of the models tried. The results of the different cases were compared and some conclusions were drawn on the effects of the various investigated modeled terms.

Linn, R.R.

1993-12-31T23:59:59.000Z

404

Comparison of Reynolds Stress Estimates Derived from Standard and Fast-Ping ADCPs  

Science Conference Proceedings (OSTI)

A field experiment was conducted to directly compare the effects of different sampling modes on Reynolds stress estimates calculated from acoustic Doppler current profilers (ADCPs). Two 1.2-MHz ADCPs were deployed concurrently over a fortnightly ...

Nicholas J. Nidzieko; Derek A. Fong; James L. Hench

2006-06-01T23:59:59.000Z

405

A System for Remote Measurements of the Wind Stress over the Ocean  

Science Conference Proceedings (OSTI)

The DISSTRESS system for remote measurements of the surface wind stress over the ocean from ships and buoys is described. It is fully digital, utilizing the inertial dissipation technique. Parallel processing allows anemometer data to be filtered ...

W. G. Large; J. A. Businger

1988-04-01T23:59:59.000Z

406

Bayesian Analysis of Step-Stress Accelerated Life Test with Exponential Distribution  

DOE Green Energy (OSTI)

In this article, we propose a general Bayesian inference approach to the step-stress accelerated life test with type II censoring. We assume that the failure times at each stress level are exponentially distributed and the test units are tested in an increasing order of stress levels. We formulate the prior distribution of the parameters of life-stress function and integrate the engineering knowledge of product failure rate and acceleration factor into the prior. The posterior distribution and the point estimates for the parameters of interest are provided. Through the Markov chain Monte Carlo technique, we demonstrate a nonconjugate prior case using an industrial example. It is shown that with the Bayesian approach, the statistical precision of parameter estimation is improved and, consequently, the required number of failures could be reduced.

Lee, J.; Pan, R.

2012-04-01T23:59:59.000Z

407

Wave–Current Interaction: A Comparison of Radiation-Stress and Vortex-Force Representations  

Science Conference Proceedings (OSTI)

The vortex-force representation of the wave-averaged effects on currents is compared to the radiation-stress representation in a scaling regime appropriate to coastal and shelf waters. Three-dimensional and vertically integrated expressions for ...

E. M. Lane; J. M. Restrepo; J. C. McWilliams

2007-05-01T23:59:59.000Z

408

Temporal Variations in Tucson, Arizona Summertime Atmospheric Moisture, Temperature and Weather Stress Levels  

Science Conference Proceedings (OSTI)

Summertime temperature, dewpoint, relative humidity, apparent temperature and weather stress levels have not changed significantly over the past 37 years at the Tucson, Arizona Municipal Airport. However, several of these variables show ...

Robert C. Balling Jr.; Sandra W. Brazel

1987-08-01T23:59:59.000Z

409

Covariability of Surface Wind and Stress Responses to Sea Surface Temperature Fronts  

Science Conference Proceedings (OSTI)

The responses of surface wind and wind stress to spatial variations of sea surface temperature (SST) are investigated using satellite observations of the surface wind from the Quick Scatterometer (QuikSCAT) and SST from the Advanced Microwave ...

Larry W. O’Neill; Dudley B. Chelton; Steven K. Esbensen

2012-09-01T23:59:59.000Z

410

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

E-Print Network (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 ...

Ganapati, Vidya

411

Development of an instrument to measure stress among software professionals: factor analytic study  

Science Conference Proceedings (OSTI)

This study investigates sources of negative pressure among software professionals, from the perspective of the software development process. A multiple response questionnaire (survey instrument) was developed to measure sources of pressure among software ... Keywords: occupational stress, software professionals

K. S. Rajeswari; R. N. Anantharaman

2003-04-01T23:59:59.000Z

412

Stress above Wind-Plus-Paddle Waves: Modeling of a Laboratory Experiment  

Science Conference Proceedings (OSTI)

A model based on wind-over-waves coupling (WOWC) theory is used to simulate a laboratory experiment and to explain the observed peculiarities of the surface stress distribution above a combined wave field: wind-generated-plus-monochromatic-paddle ...

V. K. Makin; H. Branger; W. L. Peirson; J. P. Giovanangeli

2007-12-01T23:59:59.000Z

413

Wind Stress Curl Forcing of the Coastal Ocean near Point Conception, California  

Science Conference Proceedings (OSTI)

Near Point Conception, California, the atmospheric flow separates from the coast and a large wind stress curl results. Direct spatial wind field observations from 20 aircraft overflights in the spring of 1983 suggest that Ekman pumping of on ...

Andreas Münchow

2000-06-01T23:59:59.000Z

414

Effective gravitational wave stress-energy tensor in alternative theories of gravity  

E-Print Network (OSTI)

The inspiral of binary systems in vacuum is controlled by the stress-energy of gravitational radiation and any other propagating degrees of freedom. For gravitational waves, the dominant contribution is characterized by ...

Stein, Leo Chaim

415

A Phenomenological Model for Wind Speed and Shear Stress Profiles in Vegetation Cover Layers  

Science Conference Proceedings (OSTI)

A phenomenological model for the mean wind speed and Reynolds shear stress profiles with height in a vegetation cover layer is derived from forms suggested by truncation of the equations of turbulent fluid motion at second order in fluctuating ...

F. A. Albini

1981-11-01T23:59:59.000Z

416

Sea Surface Temperature and Wind Stress Curl Variability near a Cape  

Science Conference Proceedings (OSTI)

The coupling between sea surface temperature (SST), SST gradients, and wind stress curl variability near a cape off Brazil is investigated using satellite observations and several different SST high-resolution analyses. The cape is characterized ...

Renato M. Castelao

2012-11-01T23:59:59.000Z

417

The Effective Drag Coefficient for Evaluating Wind Stress over the Oceans  

Science Conference Proceedings (OSTI)

Computations of the surface wind stress and pseudostress over the global oceans have been made using surface winds from the European Centre for Medium Range Weather Forecasts for 7 years. The drag coefficient is a function of wind speed and ...

Kevin E. Trenberth; William G. Large; Jerry G. Olson

1989-12-01T23:59:59.000Z

418

Examining Rapid Onset Drought Development Using the Thermal Infrared–Based Evaporative Stress Index  

Science Conference Proceedings (OSTI)

Reliable indicators of rapid drought onset can help to improve the effectiveness of drought early warning systems. In this study, the evaporative stress index (ESI), which uses remotely sensed thermal infrared imagery to estimate ...

Jason A. Otkin; Martha C. Anderson; Christopher Hain; Iliana E. Mladenova; Jeffrey B. Basara; Mark Svoboda

2013-08-01T23:59:59.000Z

419

Gender differences in psychopathology examined under an expanded transactional theory of stress framework  

E-Print Network (OSTI)

Prevalence rates of many types of psychopathology are lower for men than they are for women, but the causes of these discrepancies are not known. This paper focuses on two such psychopathology groups – eating disorders and depressive disorders – and examines gender differences within a transactional theory of stress that takes into account levels of cognitive processing (an expanded transactional theory of stress). Both studies found that men are more physiologically reactive to disorder-relevant, stressful stimuli and stressful events. The study on depression also found that different cognitive processes may be depressogenic for men and women: deployment of attentional resources toward negative stimuli was associated with depression in men, while deployment of attentional resources away from positive stimuli was associated with depression in women. These findings have significant implications for choosing appropriate treatment options for men and women.

Lee, Jillian April

2007-12-01T23:59:59.000Z

420

In situ stress, fracture, and fluid flow analysis in Well 38C...  

Open Energy Info (EERE)

and the ambient tectonic stresses that exist within the resource in order to design a hydraulic and thermal stimulation of an east-flank injection well, the first step in the...

Note: This page contains sample records for the topic "von mises stress" 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

Bottom Stress in Wind-Driven Depth-Averaged Coastal Flows  

Science Conference Proceedings (OSTI)

The relationship between depth-averaged velocity and bottom stress for purely wind-driven flows in unstratified coastal waters is examined using a one-dimensional (vertically resolving) current model. Results indicate that conventional drag laws ...

Harry L. Jenter; Ole Secher Madsen

1989-07-01T23:59:59.000Z

422

Computational studies of stress and structure development resulting from the coalescence of metallic islands  

E-Print Network (OSTI)

Thin film component properties are critical design elements in almost all industries. These films are particularly important in the performance of micro- and nano-electromechanical systems (MEMS and NEMS). Residual stress ...

Takahashi, Andrew Rikio

2007-01-01T23:59:59.000Z

423

Improving Stress Rupture Life of Alloy 718 by Optimizing Al, Ti ... - TMS  

Science Conference Proceedings (OSTI)

IhlPRO\\.'IIVG STRESS RUPTURE LIFE OF ALLOY 718 BY. OPTIXllZING AL, TI, P AND B CONTENTS. W. D. Cao and R. L. Kennedy. ,All\\ ac. An Allegheny ...

424

Finite Element Simulation of Residual Stresses in Thermo-coupled Wire Drawing Process  

Science Conference Proceedings (OSTI)

The objective of this paper is to calculate residual stress in drawn wire taking into account induced temperature due to plastic dissipation energy. Finite element analysis (FEA) for the simulation of wire drawing is applied. The general purpose FEA ...

R. Iankov; A. Van Bael; P. Van Houtte

2000-06-01T23:59:59.000Z

425

Effects of thermal aging on Stress Corrosion Cracking and mechanical properties of stainless steel weld metals  

E-Print Network (OSTI)

Stress Corrosion Cracking (SCC) in and around primary loop piping welds in Boiling Water Reactors has been observed worldwide as plants continue to operate at temperatures and pressures near 2880C (5500F) and 6.9 MPa (1000 ...

Hixon, Jeff

2006-01-01T23:59:59.000Z

426

Multiplying decomposition of stress/strain, constitutive/compliance relations, and strain energy  

E-Print Network (OSTI)

To account for phenomenological theories and a set of invariants, stress and strain are usually decomposed into a pair of pressure and deviatoric stress and a pair of volumetric strain and deviatoric strain. However, the conventional decomposition method only focuses on individual stress and strain, so that cannot be directly applied to either formulation in Finite Element Method (FEM) or Boundary Element Method (BEM). In this paper, a simpler, more general, and widely applicable decomposition is suggested. A new decomposition method adopts multiplying decomposition tensors or matrices to not only stress and strain but also constitutive and compliance relation. With this, we also show its practical usage on FEM and BEM in terms of tensors and matrices.

HyunSuk Lee; Jinkyu Kim

2012-11-12T23:59:59.000Z

427

In Situ–Based Pseudo–Wind Stress Products for the Tropical Oceans  

Science Conference Proceedings (OSTI)

Quality wind stress fields are desired for a wide range of oceanographic and atmospheric studies. An overview is presented of the monthly quick-look and research-quality tropical ocean wind (pseudostress) products produced for the Pacific and ...

Shawn R. Smith; Jacques Servain; David M. Legler; James N. Stricherz; Mark A. Bourassa; James J. O'Brien

2004-07-01T23:59:59.000Z

428

Influence of Cerium on Stress Corrosion Cracking in AZ91D  

Science Conference Proceedings (OSTI)

This paper considers the effect of cerium additions on the stress corrosion cracking in the Mg-Al-Zn alloy AZ91D. The two dominant phases in the AZ91D ...

429

Stress corrosion cracking and crack tip characterization of Alloy X-750 in light water reactor environments  

E-Print Network (OSTI)

Stress corrosion cracking (SCC) susceptibility of Inconel Alloy X-750 in the HTH condition has been evaluated in high purity water at 93 and 288°C under Boiling Water Reactor Normal Water Chemistry (NWC) and Hydrogen Water ...

Gibbs, Jonathan Paul

2011-01-01T23:59:59.000Z

430

High precision thermal stress study on flip chips by synchrotron polychromatic x-ray microdiffraction  

E-Print Network (OSTI)

Figure captions: Figure 1 (a) Flip chip sample attached onReferences : [1] J. H. Lau, Flip Chip Technologies , McGraw-precision thermal stress study on flip chips by synchrotron

Chen, Kai

2010-01-01T23:59:59.000Z

431

A Study of Tidal Energy Dissipation and Bottom Stress in an Estuary  

Science Conference Proceedings (OSTI)

A Method for inferring an area-averaged bottom stress and energy dissipation rate in a tidal estuarine channel is presented. The one-dimensional continuity and momentum relations are developed using simplifying assumptions appropriate for a well-...

Wendell S. Brown; Richard P. Trask

1980-11-01T23:59:59.000Z

432

Dynamic Response of Terrestrial Hydrological Cycles and Plant Water Stress to Climate Change in China  

Science Conference Proceedings (OSTI)

Rising atmospheric CO2 concentration CO2 and climate change are expected to have a major effect on terrestrial ecosystem hydrological cycles and plant water stress in the coming decades. The present study investigates the potential responses of ...

Fulu Tao; Zhao Zhang

2011-06-01T23:59:59.000Z

433

Bottom Stress Estimates from Vertical Dissipation Rate Profiles on the Continental Shelf  

Science Conference Proceedings (OSTI)

Measurements of the near-bottom distribution of the turbulent dissipation rate on the continental shelf west of Vancouver Island are used to calculate bottom stress. A free-failing vertical profiler with microstructure shear probes was used to ...

Richard K. Dewey; William R. Crawford

1988-08-01T23:59:59.000Z

434

A Study of Wind Stress Determination Methods from a Ship and an Offshore Tower  

Science Conference Proceedings (OSTI)

Comparisons are made between surface wind stress measurements obtained by the inertial-dissipation and direct covariance methods on a stable offshore tower and by the inertial-dissipation and bulk methods on a ship. The shipboard inertial-...

Paul A. Frederickson; Kenneth L. Davidson; James B. Edson

1997-08-01T23:59:59.000Z

435

Background of SIFs and Stress Indices for Moment Loadings of Piping Components  

SciTech Connect

This report provides background information, references, and equations for twenty-four piping components (thirteen component SIFs and eleven component stress indices) that justify the values or expressions for the SIFs and indices.

E. A. Wais; E. C. Rodabaugh

2005-06-15T23:59:59.000Z

436

Regulation of the periplasmic stress responses in E. coli and P. aeruginosa  

E-Print Network (OSTI)

The ability to adapt to changing environments is essential to survival. Bacteria have developed sophisticated means by which they sense and respond to stresses imposed by changes in the environment. I have undertaken the ...

Cezairliyan, Brent (Brent O.)

2008-01-01T23:59:59.000Z

437

Lidar-Observed Stress Vectors and Veer in the Atmospheric Boundary Layer  

Science Conference Proceedings (OSTI)

We demonstrate that a pulsed wind lidar is a reliable instrument for measuring angles between horizontal vectors of significance in the atmospheric boundary layer. We consider three different angles: the wind turning, the angle between the stress ...

Jacob Berg; Jakob Mann; Edward G. Patton

438

Program on Technology Innovation: Nondestructive Evaluation and Measurement of Residual Stress  

Science Conference Proceedings (OSTI)

This report summarizes the results of material characterization involving residual stress estimates that were performed on Alloy 600/182 welded plates using both X-ray diffraction (XRD) and neutron diffraction (ND) testing methods.

2008-08-14T23:59:59.000Z

439

The Response of a Stochastically Forced ENSO Model to Observed Off-Equatorial Wind Stress Forcing  

Science Conference Proceedings (OSTI)

This study investigates the response of a stochastically forced coupled atmosphere–ocean model of the equatorial Pacific to off-equatorial wind stress anomaly forcing. The intermediate-complexity coupled ENSO model comprises a linear, first ...

Shayne McGregor; Neil J. Holbrook; Scott B. Power

2009-05-01T23:59:59.000Z

440

Stress Corrosion Cracking and Crack Tip Characterization of Alloy X-750 in Light Water Reactor Environments  

E-Print Network (OSTI)

Stress corrosion cracking (SCC) susceptibility of Inconel Alloy X-750 in the HTH condition has been evaluated in high purity water at 93 and 288°C under Boiling Water Reactor Normal Water Chemistry (NWC) and Hydrogen Water ...

Gibbs, Jonathan Paul

Note: This page contains sample records for the topic "von mises stress" 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

Stress on the Mediterranean Outflow Plume: Part II. Turbulent Dissipation and Shear Measurements  

Science Conference Proceedings (OSTI)

Bottom and interfacial stresses on the Mediterranean outflow plume are estimated using vertical profiles of turbulent dissipation and velocity collected in the Gulf of Cadiz. Turbulent dissipation is high throughout the plume, with a local ...

Gregory C. Johnson; Rolf G. Lueck; Thomas B. Sanford

1994-10-01T23:59:59.000Z

442

On the Representation of Reynolds Stress in Estuaries and Shallow Coastal Seas  

Science Conference Proceedings (OSTI)

A model for the representation of the Reynolds-stress tensor in three-dimensional hydrodynamic models of shallow water flows is derived which combines the accuracy of turbulence-energy closure schemes with the computational efficiency of ...

T. J. Smith

1982-08-01T23:59:59.000Z

443

Wind-Stress coefficients over Sea surface near Neutral Conditions—A Revisit  

Science Conference Proceedings (OSTI)

A scaling law of wind-stress coefficients is presented to illustrate explicitly that the coefficient increases with wind velocity and decreases with fetch; physical reasonings of both trends are discussed. Besides being shown previously to be ...

Jin Wu

1980-05-01T23:59:59.000Z

444

Summertime Coupling between Sea Surface Temperature and Wind Stress in the California Current System  

Science Conference Proceedings (OSTI)

Satellite observations of wind stress and sea surface temperature (SST) are analyzed to investigate ocean–atmosphere interaction in the California Current System (CCS). As in regions of strong SST fronts elsewhere in the World Ocean, SST in the ...

Dudley B. Chelton; Michael G. Schlax; Roger M. Samelson

2007-03-01T23:59:59.000Z

445

Spectral Estimates of Bed Shear Stress at Subcritical Reynolds Numbers in a Tidal Boundary Layer  

Science Conference Proceedings (OSTI)

Velocity measurements from five levels in the constant-stress region of a neutrally stratified turbulent boundary layer are used to show that below a critical height the spectral energy density in the inertial subrange remains constant at a ...

Malcolm O. Green

1992-08-01T23:59:59.000Z

446

Neurobiologically-motivated treatments for post-traumatic stress disorder in an animal model  

E-Print Network (OSTI)

This thesis demonstrates that chronic immobilization stress administered to rats enhances fear learning and increases plasma acylated ghrelin. This effect is independent of the hypothalamus-pituitary-adrenal (HPA) axis ...

Meyer, Retsina Michele

2013-01-01T23:59:59.000Z

447

Mixed-Layer Shear Generated by Wind Stress in the Central Equatorial Pacific  

Science Conference Proceedings (OSTI)

Sixteen months of wind and current profile observations in the central equatorial Pacific show the response of the upper-ocean shear to local wind forcing. The shear at the ocean surface is significantly correlated with the wind stress in ...

Fernando Santiago-Mandujano; Eric Firing

1990-10-01T23:59:59.000Z

448

Pakistan Vt. J., 22(4): 2002 STRESS MANAGEMENT FOLLOWING VACCINATION AGAINST  

E-Print Network (OSTI)

Pakistan Vêt. J., 22(4): 2002 STRESS MANAGEMENT FOLLOWING VACCINATION AGAINST COCCIDIOSISPathology, 'Department ofParasitology University ofVeterinary and Animal sciences, Lahore, Pakistan ABSTRACT The présent

Paris-Sud XI, Université de

449

Evaluation of Heat Stress Risk for Workers in the Electric Power Industry: Project Update 2013  

Science Conference Proceedings (OSTI)

Heat stress remains an important risk factor affecting worker health and safety, due not only to the high and sustained workloads but also to heat contributions from the environment, machinery, and nature of protective clothing (such as arc- and fire-resistant clothing). In combination with individual factors, including age, common comorbidities (such as diabetes), fitness, and hydration levels, workers are at heat-related risk beyond overt clinical symptoms of heat stress. Regardless of the source, ...

2013-11-12T23:59:59.000Z

450

Effect of Rock Transverse Isotropy on Stress Distribution and Wellbore Fracture  

E-Print Network (OSTI)

Unconventional oil and gas, which is of major interest in petroleum industry, often occur in reservoirs with transversely isotropic rock properties such as shales. Overlooking transverse isotropy may result in deviation in stress distribution around wellbore and inaccurate estimation of fracture initiation pressure which may jeopardize safe drilling and efficient fracturing treatment. In this work, to help understand the behavior of transversely isotropic reservoirs during drilling and fracturing, the principle of generalized plane-strain finite element formulation of anisotropic poroelastic problems is explained and a finite element model is developed from a plane-strain isotropic poroelastic model. Two numerical examples are simulated and the finite element results are compared with a closed form solution and another FE program. The validity of the developed finite element model is demonstrated. Using the validated finite element model, sensitivity analysis is carried out to evaluate the effects of transverse isotropy ratios, well azimuth, and rock bedding dip on pore pressure and stress distribution around a horizontal well. The results show that their effect cannot be neglected. The short term pore pressure distribution is sensitive to Young’ modulus ratio, while the long term pore pressure distribution is only sensitive to permeability ratio. The total stress distribution generally is not sensitive to transverse isotropy ratios. The effective stress and fracture initiation are very sensitive to Young’ modulus ratio. As the well rotates from minimum horizontal in-situ stress to maximum horizontal in-situ stress, the pore pressure and stress distributions tend to be more unevenly distributed around the wellbore, making the wellbore easier to fracture. The pore pressure and stress distributions tend to "rotate" in correspondence with the rock bedding plane. The fracture initiation potential and position will alter when rock bedding orientation varies.

Lu, Chunyang

2013-08-01T23:59:59.000Z

451

Repair and Replacement Applications Center: Stress Corrosion Cracking in Closed Cooling Water Systems  

Science Conference Proceedings (OSTI)

The results of a recent EPRI project "Stress Corrosion Cracking in PWR and BWR Closed Cooling Water Systems," (EPRI Report 1009721, October 2004) indicated that approximately 10 of 143 light water reactor (LWR) plants surveyed had through-wall leaks in carbon steel piping in their closed cooling water (CCW) systems. The root cause of this leakage was intergranular stress corrosion cracking. Since there has not been extensive non-destructive testing in these systems, it is likely that the incidence rate o...

2006-09-28T23:59:59.000Z

452

Guidelines for the Optimization of Protective Clothing: Heat Stress and Skin Contamination Protection  

Science Conference Proceedings (OSTI)

Protective clothing (PCs) requirements present a challenge to radiation protection managers, particularly in environments that could potentially lead to an increased risk of heat stress. This report presents a guide to the development of a technically sound worker optimization program addressing skin contamination and heat stress risks. Project managers have successfully implemented this approach at one nuclear power plant and two Department of Energy (DOE) remediation sites.

2003-11-11T23:59:59.000Z

453

Apoplast proteome reveals that extracellular matrix contributes to multi-stress response in poplar  

SciTech Connect

Riverine ecosystems, highly sensitive to climate change and human activities, are characterized by rapid environmental change to fluctuating water levels and siltation, causing stress on their biological components. We have little understanding of mechanisms by which riverine plant species have developed adaptive strategies to cope with stress in dynamic environments while maintaining growth and development. We report that poplar (Populus spp.) has evolved a systems level 'stress proteome' in the leaf-stem-root apoplast continuum to counter biotic and abiotic factors. To obtain apoplast proteins from P. deltoides, we developed pressure-chamber and water-displacement methods for leaves and stems, respectively. Analyses of 303 proteins and corresponding transcripts coupled with controlled experiments and bioinformatics demonstrate that poplar depends on constitutive and inducible factors to deal with water, pathogen, and oxidative stress. However, each apoplast possessed a unique set of proteins, indicating that response to stress is partly compartmentalized. Apoplast proteins that are involved in glycolysis, fermentation, and catabolism of sucrose and starch appear to enable poplar to grow normally under water stress. Pathogenesis-related proteins mediating water and pathogen stress in apoplast were particularly abundant and effective in suppressing growth of the most prevalent poplar pathogen Melampsora. Unexpectedly, we found diverse peroxidases that appear to be involved in stress-induced cell wall modification in apoplast, particularly during the growing season. Poplar developed a robust antioxidative system to buffer oxidation in stem apoplast. These findings suggest that multistress response in the apoplast constitutes an important adaptive trait for poplar to inhabit dynamic environments and is also a potential mechanism in other riverine plant species.

Pechanova, Olga [Mississippi State University (MSU); Hsu, Chuan-Yu [Mississippi State University (MSU); Adams, Joshua P. [Mississippi State University (MSU); Pechan, Tibor [Mississippi State University (MSU); Vandervelde, Lindsay [Mississippi State University (MSU); Drnevich, Jenny [University of Illinois, Urbana-Champaign; Jawdy, Sara [ORNL; Adeli, Ardeshir [USDA-ARS, Mississippi State; Suttle, Jeffrey [USDA-ARS, Fargo, ND; Lawrence, Amanda [Mississippi State University (MSU); Tschaplinski, Timothy J [ORNL; Seguin, Armand [Canadian Forest Service, Sainte-Foy, Quebec; Yuceer, Cetin [Mississippi State University (MSU)

2010-01-01T23:59:59.000Z

454

A high-order boundary integral method for surface diffusions on elastically stressed axisymmetric rods  

Science Conference Proceedings (OSTI)

Many applications in materials involve surface diffusion of elastically stressed solids. Study of singularity formation and long-time behavior of such solid surfaces requires accurate simulations in both space and time. Here we present a high-order boundary ... Keywords: 65B10, 65B15, 65M99, 65R20, 74B99, Axisymmetric domain, Boundary integral method, Elastic stress, Integration factor methods, Surface diffusion

Xiaofan Li; Qing Nie

2009-07-01T23:59:59.000Z

455

Program on Technology Innovation: A Mechanistic Basis for Irradiation Assisted Stress Corrosion Cracking  

Science Conference Proceedings (OSTI)

Irradiation-assisted stress corrosion cracking (IASCC) refers to intergranular stress corrosion cracking that is accelerated under the action of irradiation in light water reactor core components. It is referred to as “assisted” because irradiation enhances, or accelerates, the IGSCC process over the non-irradiated state. IASCC has been a problem in the nuclear industry for the last 40 years and continues to occur due to a lack of understanding of its underlying mechanism. It is the single most important...

2009-09-08T23:59:59.000Z

456

Background of SIFs and Stress Indices for Moment Loadings of Piping Components  

Science Conference Proceedings (OSTI)

Design and engineering for fatigue are major concerns in piping systems. Stress indices and stress intensification factors (SIFs) are used in the design of piping systems that must meet the requirements of American Society of Mechanical Engineers (ASME) Section III Code. The majority of SIFs and indices were developed years ago when only relatively unsophisticated analysis methods were available. Many of these parameters are very conservative and result in expensive inspections, design modifications, and...

2005-06-29T23:59:59.000Z

457

Stress Testing of the Philips 60W Replacement Lamp L Prize Entry  

SciTech Connect

The Pacific Northwest National Laboratory, operated by Battelle for the U.S. Department of Energy, worked with Intertek to develop a procedure for stress testing medium screw-base light sources. This procedure, composed of alternating stress cycles and performance evaluation, was used to qualitatively compare and contrast the durability and reliability of the Philips 60W replacement lamp L Prize entry with market-proven compact fluorescent lamps (CFLs) with comparable light output and functionality. The stress cycles applied simultaneous combinations of electrical, thermal, vibration, and humidity stresses of increasing magnitude. Performance evaluations measured relative illuminance, x chromaticity and y chromaticity shifts after each stress cycle. The Philips L Prize entry lamps appear to be appreciably more durable than the incumbent energy-efficient technology, as represented by the evaluated CFLs, and with respect to the applied stresses. Through the course of testing, all 15 CFL samples permanently ceased to function as a result of the applied stresses, while only 1 Philips L Prize entry lamp exhibited a failure, the nature of which was minor, non-destructive, and a consequence of a known (and resolved) subcontractor issue. Given that current CFL technology appears to be moderately mature and no Philips L Prize entry failures could be produced within the stress envelope causing 100 percent failure of the benchmark CFLs, it seems that, in this particular implementation, light-emitting diode (LED) technology would be much more durable in the field than current CFL technology. However, the Philips L Prize entry lamps used for testing were carefully designed and built for the competition, while the benchmark CFLs were mass produced for retail sale—a distinction that should be taken into consideration. Further reliability testing on final production samples would be necessary to judge the extent to which the results of this analysis apply to production versions of the Philips L Prize entry.

Poplawski, Michael E.; Ledbetter, Marc R.; Smith, Mark

2012-04-24T23:59:59.000Z

458

Program on Technology Innovation: Development of Thin-Film Sensors to Detect Stress Corrosion Crack Initiation  

Science Conference Proceedings (OSTI)

A great amount of effort has been expended measuring stress corrosion crack (SCC) growth rates and investigating the mechanisms of SCC propagation. By contrast, relatively little effort has been devoted to studies of SCC initiation. The small amount of work on SCC initiation is due, in part, to the difficulty in investigating this phase of cracking. The main objective of the present investigation is to develop a thin-film sensor suitable for detecting and studying the initiation of intergranular stress c...

2005-12-02T23:59:59.000Z

459

Spacelike Ricci Inheritance Vectors in a Model of String Cloud and String Fluid Stress Tensor  

E-Print Network (OSTI)

We study the consequences of the existence of spacelike Ricci inheritance vectors (SpRIVs) parallel to $x^a$ for model of string cloud and string fluid stress tensor in the context of general relativity. Necessary and sufficient conditions are derived for a spacetime with a model of string cloud and string fluid stress tensor to admit a SpRIV and a SpRIV which is also a spacelike conformal Killing vector (SpCKV). Also, some results are obtained.

H. Baysal; I. Yilmaz

2005-05-02T23:59:59.000Z

460

Stress Corrosion Cracking Resistance of Weld Metals 182, 72, and 308L  

Science Conference Proceedings (OSTI)

Intergranular stress corrosion cracking (IGSCC) has occurred in alloy 182 weld metal in operating BWRs. This study compares the propagation behavior of IGSCC for nickel-base weld metal, alloy 182, with two other weld metals: type 308L stainless steel and a high-chromium nickel-base BWR candidate, alloy 72. Results indicate that weld metal 72 is more stress corrosion crack (SCC) resistant than either weld metals 182 or type 308L.

1992-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "von mises stress" 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

Elastoplastic analysis of process induced residual stresses in thermally sprayed coatings  

SciTech Connect

The residual stresses induced from thermal spraying process have been extensively investigated in previous studies. However, most of such works were focused on the elastic deformation range. In this paper, an elastoplastic model for predicting the residual stresses in thermally sprayed coatings was developed, in which two main contributions were considered, namely the deposition induced stress and that due to differential thermal contraction between the substrate and coating during cooling. The deposition induced stress was analyzed based on the assumption that the coating is formed layer-by-layer, and then a misfit strain is accommodated within the multilayer structure after the addition of each layer (plastic deformation is induced consequently). From a knowledge of specimen dimensions, processing temperatures, and material properties, residual stress distributions within the structure can be determined by implementing the model with a simple computer program. A case study for the plasma sprayed NiCoCrAlY on Inconel 718 system was performed finally. Besides some similar phenomena observed from the present study as compared with previous elastic model reported in literature, the elastoplastic model also provides some interesting features for prediction of the residual stresses.

Chen Yongxiong; Liang Xiubing; Liu Yan; Xu Binshi [National Key Laboratory for Remanufacturing, Academy of Armored Forces Engineering, Beijing 100072 (China)

2010-07-15T23:59:59.000Z

462

Exploring the Role of Shear Stress and Severe Turbulence in Downstream Fish Passage  

DOE Green Energy (OSTI)

Fish may be exposed to damaging levels of fluid shear stress and turbulence while passing through hydroelectric power plants. The generally assumed locations for such potential damage are the turbine and draft tube passages, although it is possible that fish are also injured during passage over the spillway or through sluiceways and fish bypass outfalls. Unless mitigated, fluid-induced injuries and mortality could frustrate efforts to develop advanced, fish-friendly turbines or to provide safe alternate downstream passages. The effects of shear stress and turbulence on fish are poorly understood, in part because of the difficulties in conceptualizing these phenomena, determining their magnitudes and distribution within hydroelectric systems, and then recreating them in a controlled laboratory environment. We define the fluid phenomena that are relevant to the assessment of effects on fish. The magnitudes of fluid stresses associated with man-altered aquatic environments are often considerably higher than those found in natural environments (e.g., normal river flows). However, levels of shear stresses that occur during flash floods appear to be comparable to those expected within a turbine. Past studies of the effects of shear stress on fish are of limited value, mainly because of their narrow scope and lack of instrumentation to measure velocities on appropriately small scales. A laboratory experiment to study the effects of shear stress and turbulence on fish is described.

Cada, G.; Carlson, T.; Ferguson, J.; Richmond, M.; Sale, M.

1999-07-06T23:59:59.000Z

463

Network-like propagation of cell-level stress in random foams  

E-Print Network (OSTI)

Quasistatic simple shearing flow of random monodisperse soap froth is investigated by analyzing Surface Evolver simulations of spatially periodic foams. Elastic-plastic behavior is caused by irreversible topological rearrangements (T1s) that occur when Plateau's laws are violated; the first T1s occur at the elastic limit and at large strains frequent cascades of T1s, composed of one or more individual T1s, sustain the yield-stress plateau. The stress and shape anisotropy of individual cells is quantified by $Q$, a scalar measure derived from the interface tensor that gauges each cell's contribution to the global stress. During each T1 cascade, the connected set of cells with decreasing $Q$, called the \\textit{stress release domain}, is network-like and highly non-local. Geometrically, the network-like nature of the stress release domains is corroborated through morphological analysis using the Euler characteristic. The stress release domain is distinctly different from the set of cells that change topology during a T1 cascade. Our results highlight the unique rheological behavior of foams, where complex large-scale cooperative rearrangements of foam cells are observed as a consequence of distinctly local events.

Myfanwy E. Evans; Andrew M. Kraynik; Douglas A. Reinelt; Klaus Mecke; Gerd E. Schröder-Turk

2013-05-03T23:59:59.000Z

464

Evaluation of stress in bmi-carbon fiber laminate to determine the onset of microcracking  

E-Print Network (OSTI)

In this work the conditions for which a (0,90,90,0,0,90)s BMI-carbon fiber laminate will initiate transverse microcracking are determined for the fabrication of a cryogenic fuel tank for use in a Reusable Launch Vehicle (RLV). This is accomplished using a quadratic interaction criterion failure analysis on the total stress state at possible launch conditions. There are three major sources of stress, that is, thermal residual stress, internal pressure stress, and applied load stress, that are evaluated at the launch stage to determine the total stress state. To assess the accuracy of the analysis the well known X-33 cryogenic fuel tank failure was analyzed as an example. The results of the X-33 example show that the analysis accurately portrays the failure of the X-33 and provides evidence that the analysis can be used to provide reliable conditions for the initiation of microcracking. The final result of this study is a range of launch conditions that can be used without the initiation of microcracking and a limiting range of conditions that cause complete microcracking throughout the laminate.

Pickle, Brent Durrell

2004-12-01T23:59:59.000Z

465

Determination of cohesive and normal stresses and simulation of fluidization using kinetic theory  

SciTech Connect

The general objective of this study is focused on the solid stresses involved in gas-solid flow. These stresses are generally included in the momentum conservation equations, essentially for stability and to prevent particles from collapsing to unreasonably low values of gas volume fraction. The first half of this work undertakes the measurement of the stresses in various powders by direct means, while the second part uses a newly developed kinetic theory constitutive equation for stress to predict the flow and also the solids viscosity in a CFB. The cohesive or tensile stress found to exist in some classes of powders is measured using a Cohetester, based on which a cohesive force model is derived, which is sensitive to the characteristic properties of the powder material. The normal stress is measured using a Consolidometer, and the powder solids modulus is obtained as a function of the volume fraction. The solids modulus is seen to vary with particle size and particle type, with the smaller size particles being more compressible. The simulation of flow in the CFB using Gidaspow's (1991) extension of Ding's (1990) kinetic theory model to dilute phase flow, predicts realistic values of solids viscosity that are comparable to viscosities obtained experimentally by Miller (1991). However, to obtain a match between the two the value of the restitution coefficient has to be close to unity. The flow behavior showed periodic oscillations of flow (turbulence) as seen in a real system. 26 refs., 51 figs., 1 tab.

Bezbaruah, R.

1991-08-01T23:59:59.000Z

466

Effective-stress-law behavior of Austin chalk rocks for deformation and fracture conductivity  

SciTech Connect

Austin chalk core has been tested to determine the effective law for deformation of the matrix material and the stress-sensitive conductivity of the natural fractures. For deformation behavior, two samples provided data on the variations of the poroelastic parameter, {alpha}, for Austin chalk, giving values around 0.4. The effective-stress-law behavior of a Saratoga limestone sample was also measured for the purpose of obtaining a comparison with a somewhat more porous carbonate rock. {alpha} for this rock was found to be near 0.9. The low {alpha} for the Austin chalk suggests that stresses in the reservoir, or around the wellbore, will not change much with changes in pore pressure, as the contribution of the fluid pressure is small. Three natural fractures from the Austin chalk were tested, but two of the fractures were very tight and probably do not contribute much to production. The third sample was highly conductive and showed some stress sensitivity with a factor of three reduction in conductivity over a net stress increase of 3000 psi. Natural fractures also showed a propensity for permanent damage when net stressed exceeded about 3000 psi. This damage was irreversible and significantly affected conductivity. {alpha} was difficult to determine and most tests were inconclusive, although the results from one sample suggested that {alpha} was near unity.

Warpinski, N.R.; Teufel, L.W.

1994-08-01T23:59:59.000Z

467

Thermal stress analysis of eccentric tube receiver using concentrated solar radiation  

SciTech Connect

In the parabolic trough concentrator with tube receiver system, the heat transfer fluid flowing through the tube receiver can induce high thermal stress and deflection. In this study, the eccentric tube receiver is introduced with the aim to reduce the thermal stresses of tube receiver. The ray-thermal-structural sequential coupled numerical analyses are adopted to obtain the concentrated heat flux distributions, temperature distributions and thermal stress fields of both the eccentric and concentric tube receivers. During the sequential coupled numerical analyses, the concentrated heat flux distribution on the bottom half periphery of tube receiver is obtained by Monte-Carlo ray tracing method, and the fitting function method is introduced for the calculated heat flux distribution transformation from the Monte-Carlo ray tracing model to the CFD analysis model. The temperature distributions and thermal stress fields are obtained by the CFD and FEA analyses, respectively. The effects of eccentricity and oriented angle variation on the thermal stresses of eccentric tube receiver are also investigated. It is recommended to adopt the eccentric tube receiver with optimum eccentricity and 90 oriented angle as tube receiver for the parabolic trough concentrator system to reduce the thermal stresses. (author)

Wang, Fuqiang; Shuai, Yong; Yuan, Yuan; Yang, Guo; Tan, Heping [School of Energy Science and Engineering, Harbin Institute of Technology, 92, West Dazhi Street, Harbin 150001 (China)

2010-10-15T23:59:59.000Z

468

Multifractal analysis of stress time series during ultrathin lubricant film melting  

E-Print Network (OSTI)

Melting of an ultrathin lubricant film confined between two atomically flat surfaces is we studied using the rheological model for viscoelastic matter approximation. Phase diagram with domains, corresponding to sliding, dry, and two types of $stick-slip$ friction regimes has been built taking into account additive noises of stress, strain, and temperature of the lubricant. The stress time series have been obtained for all regimes of friction using the Stratonovich interpretation. It has been shown that self-similar regime of lubricant melting is observed when intensity of temperature noise is much larger than intensities of strain and stress noises. This regime is defined by homogenous distribution, at which characteristic stress scale is absent. We study stress time series obtained for all friction regimes using multifractal detrended fluctuation analysis. It has been shown that multifractality of these series is caused by different correlations that are present in the system and also by a power-law distribution. Since the power-law distribution is related to small stresses, this case corresponds to self-similar solid-like lubricant.

A. V. Khomenko; I. A. Lyashenko; V. N. Borisyuk

2010-07-20T23:59:59.000Z

469

Residual stress of diffusion bonded aluminum-to-stainless steel joins. Final report  

SciTech Connect

An x-ray method for determination of residual stress as a function of surface position on a metal sample is described. This method is capable of spatial resolution on the order of 0.040 inch (1 mm) and precision positioning of the sample along three orthogonal axes to better than 0.001 inch. A high precision sample holder was designed and fabricated for this purpose. Apparent residual stress was found to be a strong function of sample position with respect to the axis of rotation of the diffractometer circle. This relationship is on the order of 400 to 500 Kpsi/inch for aluminum. The high precision sample holder allowed careful centering of the sample providing true (rather than apparent) residual stress measurements in the range of low stresses (less than 10 Ksi). Comparison was made between applied stress values obtained with strain gage output and those obtained by x-ray diffraction. Correlation was good with the accuracy of stress measurements being approximately +-500 psi.

Stroud, R.D.; Shackelford, J.F.

1980-09-01T23:59:59.000Z

470

Gage cookbook: Tools and techniques to measure stresses and motions on explosive experiments  

SciTech Connect

Tools and techniques developed to measure stresses and motions on underground nuclear and high explosive tests in the tuff geologies at the Nevada Test Site are described in this document. The thrust of the measurements was to understand containment phenomenology. The authors concentrate on the fluid-coupled ytterbium gage; it was fielded to measure dynamic stress in the 0.2 to 20 kilobar range and the subsequent, low amplitude residual stress. Also described are accelerometer packages; their traces were integrated to obtain particle motion. Various cable survival techniques were investigated with field measurements for they wished to extend the measurements to late-time. Field measurements were also made to address the gage inclusion problem. Work to date suggests that the problem is a minimum when the stress level is above the yield strength of the host rock and grout. Below the yield level stress amplitudes in the grouted hole can range from 60 to 200% of the stress in the host rock.

Smith, C.W. [Sandia National Labs., Albuquerque, NM (United States). Applied Technology Dept.

1996-01-01T23:59:59.000Z

471

Determination of applied stresses in rails using the acoustoelastic effect of ultrasonic waves  

E-Print Network (OSTI)

This research develops a procedure to determine the applied stresses in rails using the acoustoelastic effect of ultrasonic waves. Acoustoelasticity is defined as the stress dependency of ultrasonic wave speed or wave polarization. Analytical models are developed that predict the acoustoelastic effect for longitudinal waves, shear waves, Lamb waves, and Rayleigh waves. Using a programming tool, a numerical simulation of the models is generated to obtain the stress dependent curves of wave velocity and polarization of the various ultrasonic waves propagating in rail steel. A comparison of the sensitivity of the acoustoelastic effect is made to determine the feasibility of ultrasonic waves for further study. Rayleigh waves are found to be most sensitive to stress change. Rayleigh waves are generated using ultrasonic transducer and detected using a laser Doppler vibrometer (LDV). The LDV measures the in-plane and out-of-plane velocities. Polarization is defined as the ratio of in-plane and out-of-plane displacements. Initially, polarization is determined for the specimen in unstressed condition. Thereafter, the rail specimen is stressed in a compression testing machine, the experiment repeated, and the polarization determined. Thus, Rayleigh wave polarization is obtained as a function of applied stress. Finally, the change in polarization obtained experimentally is compared with the analytical model.

Gokhale, Shailesh Ashok

2007-12-01T23:59:59.000Z

472

Stress Isotherms of Porous Thin Materials: Theoretical Predictitions From a Nonlocal Density Functional Theory  

SciTech Connect

Recent beam bending (BB) experiments of microporous t31rns with very small pores have shown that the fluid confined in these pores exhibits monotonic compressive stresses as the relative pressure is varied from vacuum to saturation (relative vapor pressure, p/p. = 1). The variation of the stress near saturation is found to be linear in hz(p) and given by the saturated liquid density to within 20%. Capillary condensed fluids are traditionally described by the Laplace-Kelvin (LK) theory. LK theory correctly predicts the slope of the stress near saturation to be pl, but also predicts that the stress should be zero at saturation and tensile between saturation aud the capillary transition pressure. Hence LK theory does not capture the monotonic compressive stress observed in BB experiments. This report describes the results of density functional theory calculations for a simple fluid continued to a slit pore network. We show how the presence of even a small amount of polydispersity in pore size leads to both a monotonic compressive stress as well as the observed LK slope.

Frink, L.J.D.; van Swol, F.

1998-11-11T23:59:59.000Z

473

A virtual reality system for the treatment of stress-related disorders: A preliminary analysis of efficacy compared to a standard cognitive behavioral program  

Science Conference Proceedings (OSTI)

This paper presents preliminary efficacy data in a controlled study of the use of a virtual reality (VR) system for treating stress-related disorders (Post-Traumatic Stress Disorder, or PTSD; Pathological Grief, or PG; and Adjustment Disorders, or AD). ... Keywords: Adjustment Disorder, Pathological Grief, Post-Traumatic Stress Disorder, Psychological treatments, Stress-related disorders, Virtual reality

R. M. Baños; V. Guillen; S. Quero; A. García-Palacios; M. Alcaniz; C. Botella

2011-08-01T23:59:59.000Z

474

Minimally-invasive Wearable Sensors and Data Processing Methods for Mental Stress Detection  

E-Print Network (OSTI)

Chronic stress is endemic to modern society. If we could monitor our mental state, we may be able to develop insights about how we respond to stress. However, it is unfeasible to continuously annotate stress levels all the time. In the studies conducted for this dissertation, a minimally-invasive wearable sensor platform and physiological data processing methods were developed to analyze a number of physiological correlates of mental stress. We present a minimally obtrusive wearable sensor system that incorporates embedded and wireless communication technologies. The system is designed such that it provides a balance between data collection and user comfort. The system records the following stress related physiological and contextual variables: heart rate variability (HRV), respiratory activity, electrodermal activity (EDA), electromyography (EMG), body acceleration, and geographical location. We assume that if the respiratory influences on HRV can be removed, the residual HRV will be more salient to stress in comparison with raw HRV. We develop three signal processing methods to separate HRV into a respiration influenced and residual HRV. The first method consists of estimating respiration-induced portion of HRV using a linear system identification method (autoregressive moving average model with exogenous inputs). The second method consists of decomposing HRV into respiration-induced principal dynamic mode and residual using nonlinear dynamics decomposition method (principal dynamic mode analysis). The third method consists of splitting HRV into respiration-induced power spectrum and residual in frequency domain using spectral weighting method. These methods were validated on a binary discrimination problem of two psychophysiological conditions: mental stress and relaxation. The linear system identification method, nonlinear dynamics decomposition method, and spectral weighting method classified stress and relaxation conditions at 85.2 %, 89.2 %, and 81.5 % respectively. When tonic and phasic EDA features were combined with the linear system identification method, the nonlinear dynamics decomposition method, and the spectral weighting method, the average classification rates were increased to 90.4 %, 93.2 %, and 88.1 % respectively. To evaluate the developed wearable sensors and signal processing methods on multiple subjects, we performed case studies. In the first study, we performed experiments in a laboratory setting. We used the wearable sensors and signal processing methods to discriminate between stress and relaxation conditions. We achieved 81 % average classification rate in the first case study. In the second study, we performed experiments to detect stress in ambulatory settings. We collected data from the subjects who wore the sensors during regular daily activities. Relaxation and stress conditions were allocated during daily activities. We achieved a 72 % average classification rate in ambulatory settings. Together, the results show achievements in recognizing stress from wearable sensors in constrained and ambulatory conditions. The best results for stress detection were achieved by removing respiratory influence from HRV and combining features from EDA.

Choi, Jongyoon

2011-12-01T23:59:59.000Z

475

Measurement of residual stress in quenched 1045 steel by the nanoindentation method  

Science Conference Proceedings (OSTI)

In this paper, the residual stress in quenched AISI 1045 steel was measured by a recently developed nanoindentation technique. Depth control mode was adopted to measure the residual stress. It was found that residual compressive stress was generated in the quenched steel. The material around nanoindents exhibits significant pile-up deformation. A new method was proposed to determine the real contact area for pile-up material on the basis of invariant pile-up morphology of the loaded or unloaded states. The results obtained by the new method were in good agreement with the residual stresses measured by the classical X-ray diffraction (XRD) method. - Research Highlights: {yields} A new method was proposed to measure the real contact area for pile-up materials. {yields} The real contact depth is defined as the sum of h{sub max} and the pile-up height h{sub p}. {yields} The value of residual stress measured by the nanoindentation method was in good agreement with that by the XRD method.

Zhu Lina, E-mail: zhulina84@gmail.com [School of Engineering and Technology, China University of Geosciences, Beijing 100083 (China); National Key Laboratory for Remanufacturing, Academy of Armored Forces Engineering, Beijing 100072 (China); Xu Binshi; Wang Haidou [National Key Laboratory for Remanufacturing, Academy of Armored Forces Engineering, Beijing 100072 (China); Wang Chengbiao [School of Engineering and Technology, China University of Geosciences, Beijing 100083 (China)

2010-12-15T23:59:59.000Z

476

ANALYSIS OF STRESSES AND DEFLECTIONS IN TOP SUPPORT GRID, PWR REACTOR. Final Report  

SciTech Connect

The top grid of the PWR reactor core assembly is treated as a simply supported circular plate. The theory of plate is applied to the grid umder mechanical loads. The thermal stress problem is analyzed by treating the plate as under combined action of a laterally distributed load and forces in the middle plane of the plate. The load distribution is calculated from the temperature variation over the grid. The thermal stress problem then is equivalent to two problems: one, of bendimg of plate; and, the other, a plane stress problem. The theoretical formulation for plates under nonuniform heating is developed by neglecting the effect of uneven expansion in the direction perpendicular to the plane of the plate. In replacing the partial dffferential equations by difference equations, the latter are modified to take into account the change in tbickmess and spacing of the grid webs near the boundary. Twentythree difference equations for the twenty-three stations in one octant of the grid are obtained for each second order partial differential equation. The difference equations are solved by assuming that the twisting moments and shearing stresses in the plane of the grid vanish at the boundary. The stresses and deflections due to mechanical loads and thermal expansion are then superposed. (auth)

Yen, T.C.; Vining, R.E. Jr.

1957-06-01T23:59:59.000Z

477

Ageing under oscillatory stress: Role of energy barrier distribution in thixotropic materials  

E-Print Network (OSTI)

In this work the ageing dynamics of soft solids of aqueous suspension of laponite has been investigated under the oscillatory stress field. We observed that at small stresses elastic and viscous moduli showed a steady rise with the elastic modulus increasing at a faster rate than the viscous modulus. However at higher stresses both the moduli underwent a sudden rise by several orders of magnitude with the onset of rise getting shifted to a higher age for a larger shear stress. We believe that the observed behavior is due to interaction of barrier height distribution of the potential energy wells in which the particle is trapped and strain induced potential energy enhancement of the particles. Strain induced in the material causes yielding of the particles that are trapped in the shallower wells. Those trapped in the deeper wells continue to age enhancing the cage diffusion timescale and thereby the viscosity which lowers the magnitude of strain allowing more particles to age. This coupled dependence of strain, viscosity and ageing causes forward feedback for a given magnitude of stress leading to sudden rise in both the moduli. Changing the microstructure of the laponite suspension by adding salt affected the barrier heights distribution that showed a profound influence on the ageing behavior. Interestingly, this study suggests a possibility that any apparently yielded material with negligible elastic modulus, may get jammed at a very large waiting time.

Asheesh Shukla; Yogesh M. Joshi

2008-06-26T23:59:59.000Z

478

Shock initiation studies of low density HMX using electromagnetic particle velocity and PVDF stress gauges  

Science Conference Proceedings (OSTI)

Magnetic particle velocity and PVDF stress rate gauges have been used to measure the shock response of low density octotetramethylene tetranitramine (HMX) (1.24 &/cm{sup 3}). In experiments done at LANL, magnetic particle velocity gauges were located on both sides of the explosive. In nearly identical experiments done at SNL, PVDF stress rate gauges were located at the same positions so both particle velocity and stress histories were obtained for a particular experimental condition. Unreacted Hugoniot data were obtained and an EOS was developed by combining methods used by Hayes, Sheffield and Mitchell (for describing the Hugoniot of HNS at various densities) with Hermann`s P-{alpha} model. Using this technique, it is only necessary to know some thermodynamic constants or the Hugoniot of the initially solid material and the porous material sound speed to obtain accurate unreacted Hugoniots for the porous explosive. Loading and reaction paths were established in the stress-particle velocity plane for some experimental conditions. This information was used to determine a global reaction rate of {approx} 0.13 {mu}s{sup {minus}1} for porous HMX shocked to 0.8 GPa. At low input stresses the transmitted wave profiles had long rise times (up to 1 {mu}s) due to the compaction processes.

Sheffield, S.A.; Gustavsen, R.L.; Alcon, R.R. [Los Alamos National Lab., NM (United States); Graham, R.A.; Anderson, M.U. [Sandia National Labs., Albuquerque, NM (United States)

1993-09-01T23:59:59.000Z

479

Remote sensing for site-specific management of biotic and abiotic stress in cotton  

E-Print Network (OSTI)

This study evaluated the applicability of remote sensing instrumentation for site- specific management of abiotic and biotic stress on cotton grown under a center pivot. Three different irrigation regimes (100%, 75%, and 50% ETc) were imposed on a cotton field to 1) monitor canopy temperatures of cotton with infrared thermometers (IRTs) in order to pinpoint areas of biotic and abiotic stress, 2) compare aerial infrared photography to IRTs mounted on center pivots to correlate areas of biotic and abiotic stress, and 3) relate yield to canopy temperatures. Pivot-mounted IRTs and IR camera were able to differentiate water stress between the irrigation regimes, however, only the IR camera was effectively able to distinguish between biotic (cotton root rot) and abiotic (drought) stress with the assistance of groundtruthing. The 50% ETc regime had significantly higher canopy temperatures, which were reflected in significantly lower lint yields when compared to the 75% and 100% ETc regimes. Deficit irrigation up to 75% ETc had no impact on yield, indicating that water savings were possible without yield depletion.

Falkenberg, Nyland Ray

2005-05-01T23:59:59.000Z

480

FITNESS-FOR-SERVICE ASSESSMENT FOR A RADIOACTIVE WASTE TANK THAT CONTAINS STRESS CORROSION CRACKS  

Science Conference Proceedings (OSTI)

Radioactive wastes are confined in 49 underground storage tanks at the Savannah River Site. The tanks are examined by ultrasonic (UT) methods for thinning, pitting, and stress corrosion cracking in order to assess fitness-for-service. During an inspection in 2002, ten cracks were identified on one of the tanks. Given the location of the cracks (i.e., adjacent to welds, weld attachments, and weld repairs), fabrication details (e.g., this tank was not stress-relieved), and the service history the degradation mechanism was stress corrosion cracking. Crack instability calculations utilizing API-579 guidance were performed to show that the combination of expected future service condition hydrostatic and weld residual stresses do not drive any of the identified cracks to instability. The cracks were re-inspected in 2007 to determine if crack growth had occurred. During this re-examination, one indication that was initially reported as a 'possible perpendicular crack API-579 crack instability calculations were again performed, based on expected future service conditions and trended crack growth rates for the future tank service cycle. The analysis showed that the combined hydrostatic and weld residual stresses do not drive the identified cracks to instability. This tank expected to be decommissioned in the near future. However, if these plans are delayed, it was recommended that a third examination of selected cracks in the tank be performed in 2014.

Wiersma, B; James Elder, J; Rodney Vandekamp, R; Charles Mckeel, C

2009-04-23T23:59:59.000Z

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481

Effects of localized geometric imperfections on the stress behavior of pressurized cylindrical shells  

E-Print Network (OSTI)

The influence of dent imperfections on the elastic stress behavior of cylindrical shells is explored. This problem is of central importance to the prediction of fatigue failure due to dents in petroleum pipelines. Using an approximate technique called the Equivalent Load Method, a semi-analytical model of two-dimensional dent stress behavior is developed. In the three-dimensional situation, decreased dent localization, in particular dent length, and increased dent depth are confirmed to cause dent stress concentration behavior to shift from having a single peak at the dent center to having peaks at the dent periphery. It is demonstrated that the equivalent load method does not predict this shift in stress behavior and cannot be relied upon to analyze relatively small, deep imperfections. The two stress modes of dents are associated with two modes of dent fatigue behavior that have significantly different fatigue lives. A method for distinguishing longer lived Mode P dents from shorter lived Mode C dents based on two measured features of dent geometry is developed and validated. An approach for implementing this analysis in the evaluation of real dents is also suggested.

Rinehart, Adam James

2003-08-01T23:59:59.000Z

482

Insights Gained from Ultrasonic Testing of Piping Welds Subjected to the Mechanical Stress Improvement Process  

SciTech Connect

Pacific Northwest National Laboratory (PNNL) is assisting the United States Nuclear Regulatory Commission (NRC) in developing a position on the management of primary water stress corrosion cracking (PWSCC) in leak-before-break piping systems. Part of this involves determining whether inspections alone, or inspections plus mitigation, are needed. This work addresses the reliability of ultrasonic testing (UT) of cracks that have been mitigated by the mechanical stress improvement process (MSIP). The MSIP has been approved by the NRC (NUREG-0313) since 1986 and modifies residual stresses remaining after welding with compressive, or neutral, stresses near the inner diameter surface of the pipe. This compressive stress is thought to arrest existing cracks and inhibit new crack formation. To evaluate the effectiveness of the MSIP and the reliability of ultrasonic inspections, flaws were evaluated both before and after MSIP application. An initial investigation was based on data acquired from cracked areas in 325-mm-diameter piping at the Ignalina Nuclear Power Plant (INPP) in Lithuania. In a follow-on exercise, PNNL acquired and evaluated similar UT data from a dissimilar metal weld (DMW) specimen containing implanted thermal fatigue cracks. The DMW specimen is a carbon steel nozzle-to-safe end-to-stainless steel pipe section that simulates a pressurizer surge nozzle. The flaws were implanted in the nozzle-to-safe end Alloy 82/182 butter region. Results are presented on the effects of MSIP on specimen surfaces, and on UT flaw responses.

Anderson, Michael T.; Cinson, Anthony D.; Crawford, Susan L.; Diaz, Aaron A.; Moran, Traci L.

2010-12-01T23:59:59.000Z

483

Stress-Energy Tensor of the Quantized Massive Fields in Friedman-Robertson-Walker Spacetimes  

E-Print Network (OSTI)

The approximate stress-energy tensor of the quantized massive scalar, spinor and vector fields in the spatially flat Friedman-Robertson-Walker universe is constructed. It is shown that for the scalar fields with arbitrary curvature coupling the stress-energy tensor calculated within the framework of the Schwinger-DeWitt approach is identical to the analogous tensor constructed in the adiabatic vacuum. Similarly, the Schwinger-DeWitt stress-energy tensor for higher spins coincides with the analogous result calculated by the Zeldovich-Starobinsky method. The thus obtained stress-energy tensor are subsequently used in the back reaction problem. It is shown that for pure semiclassical Einstein field equations with the vanishing cosmological constant and the source term consisting exclusively of its quantum part there are no self-consistent exponential solutions driven by the spinor and vector field. A similar situation takes place for the conformally coupled scalar field and the allowable values of the coupling constant belong to the interval $\\xi \\lesssim 0.1.$ The perturbative approach to the problem is briefly discussed and possible generalizations of the stress-energy tensor are indicated.

Jerzy Matyjasek; Pawe? Sadurski

2013-09-02T23:59:59.000Z

484

Electrodeposition of nickel from low temperature sulfamate electrolytes.Part 1 :Electrochemistry and film stress.  

DOE Green Energy (OSTI)

The film stress of Ni films deposited at near-ambient temperatures from sulfamate electrolytes was studied. The particulate filtering of the electrolyte, a routine industrial practice, becomes an important deposition parameter at lower bath temperatures. At 28 C, elevated tensile film stress develops at low current densities (<10 mA/cm{sup 2}) if the electrolyte is filtered. Filtering at higher current densities has a negligible effect on film stress. A similar though less pronounced trend is observed at 32 C. Sulfate-based Ni plating baths display similar film stress sensitivity to filtering, suggesting that this is a general effect for Ni electrodeposition. It is shown that filtering does not significantly change the current efficiency or the pH near the surface during deposition. The observed changes in film stress are thus attributed not to adsorbed hydrogen but instead to the effects of filtering on the formation and concentration of polyborate species due to the decreased solubility of boric acid at near-ambient temperatures.

Hachman, John T.; Kelly, J.J. (IBM/T.J. Watson Research Center, Yorktown Heights, NY); Talin, Albert Alec; Goods, Steven Howard

2005-11-01T23:59:59.000Z

485

Apparatus for pre-stress-straining rod-type specimens in tension for in-situ passive fracture testing  

DOE Patents (OSTI)

A stress-strain testing apparatus imposes a stress-strain on a specimen while disposed in a controlled environment. Each end of the specimen is fastened to an end cap and a strain gage is attached to the specimen. An adjusting mechanism and a compression element are disposed between the end caps forming a frame for applying forces to the end caps and thereby stress-straining the specimen. The adjusting mechanism may be extended or retracted to increase or decrease the imposed stress-strain on the specimen, and the stress-strain is measured by the strain gage on the specimen while the apparatus is exposed to an environment such as high pressure hydrogen. Strain gages may be placed on the frame to measure stress-strains in the frame that may be caused by the environment.

Wang, John Jy-an (Oak Ridge, TN); Liu, Ken C. (Oak Ridge, TN); Feng, Zhili (Knoxville, TN)

2013-07-31T23:59:59.000Z

486

Young's modulus, Poisson's ratio, and residual stress and strain in (111)-oriented scandium nitride thin films on silicon  

E-Print Network (OSTI)

cyclotron resonance MBE which typically generate N2 + species with high kinetic energies. The causes of compressive stress in this case may instead be related to a trend commonly observed in vapor-deposited thin films. Such films typically experience... with the strain information hich is found to be 270±25 GPa. Residual m growth temperature and film thickness#2; d by the differential thermal contraction ic compressive stresses generated during .1063/1.2217106#5; Accurate determination of residual stresses...

Moram, M A; Barber, Z H; Humphreys, C J; Joyce, T B; Chalker, P R

2006-07-21T23:59:59.000Z

487

Materials Reliability Program: Welding Residual Stress Dissimilar Metal Butt-Weld Finite Element Modeling Handbook (MRP-317)  

Science Conference Proceedings (OSTI)

The residual stresses imparted by the welding process are a principal factor in the process of primary water stress corrosion cracking (PWSCC) of Alloy 82/182 nickel-alloy (i.e., dissimilar metal) piping butt welds in pressurized water reactors (PWRs). Numerical methods by finite element analyses are frequently used to simulate the welding process in order to predict the residual stress distribution in the weld and base material as an input to crack growth calculations. The crack growth calculations, in ...

2011-12-22T23:59:59.000Z

488

Physics-Based Stress Corrosion Cracking Component Reliability Model cast in  

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

Physics-Based Stress Corrosion Cracking Component Reliability Model Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage Framework Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage Framework The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). The methodology emerging from the RISMC pathway is not a conventional probabilistic risk assessment (PRA)-based one; rather, it relies on a reactor systems simulation framework in which

489

Microsoft Word - Lamellae tungsten tile design thermal and electromagnetic stress analysis_Final.doc  

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

Lamellae tungsten tile design transient Lamellae tungsten tile design transient thermal/ electromagnetic stress analysis Thomas Willard*, Rui Vieira, Samuel Pierson MIT Plasma Science and Fusion Center, Cambridge, MA 02139 8 June 2006 Abstract A transient thermal/ electromagnetic stress analysis of the lamellae tungsten tile design has been performed to determine if the design is adequate to meet the maximum design load conditions of 12 MW/ m 2 uniform heat flux for 5 seconds (single pulse, no Diverter Plate temperature ratcheting) , superimposed on the electromagnetic body load due to eddy currents generated by disruptions. The results show that the design is adequate, with the stresses in the tungsten lamellae and the TZM molybdenum hardware less than the ultimate strength of

490

Physics-Based Stress Corrosion Cracking Component Reliability Model cast in  

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

Physics-Based Stress Corrosion Cracking Component Reliability Model Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage Framework Physics-Based Stress Corrosion Cracking Component Reliability Model cast in an R7-Compatible Cumulative Damage Framework The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). The methodology emerging from the RISMC pathway is not a conventional probabilistic risk assessment (PRA)-based one; rather, it relies on a reactor systems simulation framework in which

491

Gene Expression Analysis of Apoptosis and Oxidative Stress in Mouse Brain  

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

Analysis of Apoptosis and Oxidative Stress in Mouse Brain Analysis of Apoptosis and Oxidative Stress in Mouse Brain After Low-dose and Acute Radiation Exposure Daila Gridley Loma Linda University & Medical Center Abstract Purpose: 1) To examine the induction of oxidative stress and apoptosis-associated gene expression profiles in brain after whole-body irradiation with low-dose/low-dose-rate (LDR) photons and acute exposure to photons 2) to compare these radiation-induced effects with those produced by LDR and acute exposure to protons. Material and Methods: C57BL/6 mice were exposed to 2 Gy of photons or protons at 0.8 Gy/min and 0.9 Gy/min, respectively, both with and without pre-exposure to 0.01 Gy LDR γ-rays (57Co) at 0.03 cGy/h. Brain tissues were harvested and quick-frozen for analyses by quantitative RTPCR at 56

492

Seismicity and seismic stress in the Coso Range, Coso geothermal field, and  

Open Energy Info (EERE)

Seismicity and seismic stress in the Coso Range, Coso geothermal field, and Seismicity and seismic stress in the Coso Range, Coso geothermal field, and Indian Wells Valley region, Southeast-Central California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Book: Seismicity and seismic stress in the Coso Range, Coso geothermal field, and Indian Wells Valley region, Southeast-Central California Details Activities (1) Areas (1) Regions (0) Abstract: The temporal and spatial distribution of seismicity in the Coso Range, the Coso geothermal field, and the Indian Wells Valley region of southeast-central California are discussed in this paper. An analysis of fault-related seismicity in the region led us to conclude that the Little Lake fault and the Airport Lake fault are the most significant seismogenic zones. The faulting pattern clearly demarcates the region as a transition

493

A Review of Stress Corrosion Cracking/Fatigue Modeling for Light Water  

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

A Review of Stress Corrosion Cracking/Fatigue Modeling for Light A Review of Stress Corrosion Cracking/Fatigue Modeling for Light Water Reactor Cooling System Components A Review of Stress Corrosion Cracking/Fatigue Modeling for Light Water Reactor Cooling System Components In the United States currently there are approximately 104 operating light water reactors. Of these, 69 are pressurized water reactors (PWRs) and 35 are boiling water reactors (BWRs). In 2007, the 104 light-water reactors (LWRs) in the United States generated approximately 100 GWe, equivalent to 20% of total US electricity production. Most of the US reactors were built before 1970 and the initial design lives of most of the reactors are 40 years. It is expected that by 2030, even those reactors that have received 20-year life extension license from the US Nuclear Regulatory Commission

494

Residual stress determination in an overlay dissimilar welded pipe by neutron diffraction  

Science Conference Proceedings (OSTI)

Residual stresses were determined through the thickness of a dissimilar weld overlay pipe using neutron diffraction. The specimen has a complex joining structure consisting of a ferritic steel (SA508), austenitic steel (F316L), Ni-based consumable (Alloy 182), and overlay of Ni-base superalloy (Alloy 52M). It simulates pressurized nozzle components, which have been a critical issue under the severe crack condition of nuclear power reactors. Two neutron diffractometers with different spatial resolutions have been utilized on the identical specimen for comparison. The macroscopic 'stress-free' lattice spacing (d{sub o}) was also obtained from both using a 2-mm width comb-like coupon. The results show significant changes in residual stresses from tension (300-400 MPa) to compression (-600 MPa) through the thickness of the dissimilar weld overlay pipe specimen.

Woo, Wan Chuck [ORNL; Em, Vyacheslav [Korea Atomic Energy Research Institute; Hubbard, Camden R [ORNL; Lee, Ho-Jin [Korea Atomic Energy Research Institute; Park, Kwang Soo [Doosan Heavy Industries & Construction

2011-01-01T23:59:59.000Z

495

The Stress-Energy Tensor of Flavor Fields from AdS/CFT  

E-Print Network (OSTI)

We use the AdS/CFT correspondence to study the transport properties of massive N=2 hypermultiplet fields in an N=4 SU(Nc) super-Yang-Mills theory plasma in the large Nc, large 't Hooft coupling limit, and in the presence of a baryon number chemical potential and external electric and magnetic fields. In particular, we compute the flavor fields' contribution to the stress-energy tensor. We find infrared divergences in the stress-energy tensor, arising from the flavor fields' constant rate of energy and momentum loss. We regulate these divergences and extract the energy and momentum loss rates from the divergent terms. We also check our result in various limits in which the divergences are absent. The supergravity dual is a system of D7-branes, with a particular configuration of worldvolume fields, probing an AdS-Schwarzschild background. The supergravity calculation amounts to computing the stress-energy tensor of the D7-branes.

Andreas Karch; Andy O'Bannon; Ethan Thompson

2008-12-18T23:59:59.000Z

496

Stress Analysis of Floor Slab from Hyster 550 FS Lift Truck with 55 Kip Pay Load  

Science Conference Proceedings (OSTI)

The objective of this calculation is to determine the probable moments and stresses that will be induced into the slab on grade floor at building 2404WA from operation of a Hyster 550 FS lift truck having tire pressures of 124 psi while moving and placing SWDB boxes within building 2404WA. It was found that the probable reinforcing steel stress induced in the grade 60 reinforcing steel for the 124 psi tire pressure is about 35.55 ksi and the factor of safety against yield is about 1.7:l. The probable maximum concrete compression stress is expected to be about 2.21 ksi resulting in a factor of safety of about 2.04:1 against concrete compression failure. Slab on grade design is not subject to building code factors of safety requirements.

BLACK, D.G.

2003-06-05T23:59:59.000Z

497

Frequency-domain stress prediction algorithm for the LIFE2 fatigue analysis code  

SciTech Connect

The LIFE2 computer code is a fatigue/fracture analysis code that is specialized to the analysis of wind turbine components. The numerical formulation of the code uses a series of cycle mount matrices to describe the cyclic stress states imposed upon the turbine. However, many structural analysis techniques yield frequency-domain stress spectra and a large body of experimental loads (stress) data is reported in the frequency domain. To permit the analysis of this class of data, a Fourier analysis module has been added to the code. The module transforms the frequency spectrum to an equivalent time series suitable for rainflow counting by other modules in the code. This paper describes the algorithms incorporated into the code and uses experimental data to illustrate their use. 10 refs., 11 figs.

Sutherland, H.J.

1992-01-01T23:59:59.000Z

498

Experimental measurement and numerical simulation of residual stresses in a carburized layer of a 5120 steel  

Science Conference Proceedings (OSTI)

A combined experimental and numerical study of residual stress and microstructure has been performed for a carburized steel 5120 specimen. Specimens were cut from 5120 steel bar stock, in the shape of hockey pucks and were subsequently carburized and quenched. X-ray diffraction was used to record stress profiles through the case for the martensite and retained austenite on the two flat surfaces oriented up and down during the quench. Layer removal was performed by electropolishing. Rietveld analysis was used to determine the lattice parameters of the phases at each depth varying with both carbon content and stress. The experimental measurements are compared with a numerical simulation of the phase transformation and the metallurgical changes following the carburization and quench. Results am discussed in the context of the microstructure and the role played by the retained austenite in interpretation. In addition the carbon profile obtained from the lattice parameters is compared with profiles measured using burnout.

Rangaswamy, P.; Bourke, M.A.M.; Shipley, J.C.; Goldstone, J.A.

1995-09-01T23:59:59.000Z

499

Comparing of Normal Stress Distribution in Static and Dynamic Soil-Structure Interaction Analyses  

Science Conference Proceedings (OSTI)

It is important to consider the vertical component of earthquake loading and inertia force in soil-structure interaction analyses. In most circumstances, design engineers are primarily concerned about the analysis of behavior of foundations subjected to earthquake-induced forces transmitted from the bedrock. In this research, a single rigid foundation with designated geometrical parameters located on sandy-clay soil has been modeled in FLAC software with Finite Different Method and subjected to three different vertical components of earthquake records. In these cases, it is important to evaluate effect of footing on underlying soil and to consider normal stress in soil with and without footing. The distribution of normal stress under the footing in static and dynamic states has been studied and compared. This Comparison indicated that, increasing in normal stress under the footing caused by vertical component of ground excitations, has decreased dynamic vertical settlement in comparison with static state.

Kholdebarin, Alireza; Massumi, Ali [Graduate School of Engineering, Tarbiat Moallem University of Tehran (Kharazmi), Tehran (Iran, Islamic Republic of); Davoodi, Mohammad [Dept. of Geotechnical Earthquake Engineering, International Institute of Earthquake Engineering and Seismology, IIEES, Tehran (Iran, Islamic Republic of); Tabatabaiefar, Hamid Reza

2008-07-08T23:59:59.000Z

500

Capabilities of the High Voltage Stress Test System at the Outdoor Test Facility  

DOE Green Energy (OSTI)

We illustrate the capabilities of the High Voltage Stress Test (HVST) which operates continuously in the array field east of the Outdoor Test Facility at the National Renewable Energy Laboratory. Because we know that photovoltaic (PV) modules generating electrical power in both residential and utility-scale array installations will develop high-voltage biases approaching 600 VDC and 1,000 VDC, respectively, we expect such high voltages will result in current leakage between cells and ground, typically through the frames or mounts. We know that inevitably such leakage currents are capable of producing electrochemical corrosion that adversely impacts long-term module performance. With the HVST, we stress or operate PV modules under high-voltage bias, to characterize their leakage currents under all prevailing ambient conditions and assess performance changes emanating from high-voltage stress. We perform this test both on single modules and an active array.

del Cueto, J. A.; Trudell, D.; Sekulic, W.

2005-11-01T23:59:59.000Z