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Sample records for leonardas kairiuktis jone

  1. Lyle V. Jones: Biography

    ERIC Educational Resources Information Center

    Journal of Educational and Behavioral Statistics, 2003

    2003-01-01

    Lyle V. Jones served as director of the Thurstone Psychometric Laboratory and also became the Vice Chancellor and Dean of the Graduate School of the University of North Carolina (UNC). Jones has been a Research Professor at UNC since 1992. This article presents an interview with Jones wherein he talked about his career as a researcher. Jones also…

  2. On the existence of Jones birefringence and Jones dichroism.

    PubMed

    Arteaga, Oriol

    2010-05-01

    We claim that the so-called Jones birefringence and Jones dichroism effects, understood as new optical phenomena of difficult experimental observation, cannot be deduced from Jones publications and were proposed due to a misinterpretation of his original work.

  3. Snorkeling and Jones tubes.

    PubMed

    Lam, Lewis Y W; Weatherhead, Robert G

    2015-01-01

    We report a case of tympanic membrane rupture during snorkeling in a 17-year-old young man who had previously undergone bilateral Jones tubes placed for epiphora. To our knowledge, this phenomenon has not been previously reported.

  4. Interview with Loyal Jones.

    ERIC Educational Resources Information Center

    Briscoe, Lori; Collins, Erica S.; Deal, Amanda; Hancock, Ron; McGraw, Kristyn

    2000-01-01

    Loyal Jones talks about his role in the Council of the Southern Mountains, the controversy that led to its demise, founding the Appalachian Center at Berea College (Kentucky), and elitist attitudes of liberal arts colleges that hinder sincere efforts to help Appalachian people. He discusses humor as a way of simultaneously putting people on and…

  5. Snorkeling and Jones tubes

    PubMed Central

    Lam, Lewis Y. W.; Weatherhead, Robert G.

    2015-01-01

    Summary We report a case of tympanic membrane rupture during snorkeling in a 17-year-old young man who had previously undergone bilateral Jones tubes placed for epiphora. To our knowledge, this phenomenon has not been previously reported. PMID:27330470

  6. Verina Morton Jones, MD.

    PubMed

    Rishworth, Susan K

    2012-01-01

    The purpose of this historical article is to demonstrate, as the biography of Verina Morton Jones, MD, is uncovered, the difficulties inherent in researching original source material on the lives of 19th- and early 20th-century African American physicians as well as the great benefits derived from doing this research. The procedures used include basic archival research and close examination of published materials about her in the past, in conjunction with oral history. Original correspondence from Dr Morton Jones to her niece and nephew is used to illustrate events in her life and the thoughts and attitudes she expressed. Some of these thoughts and attitudes reflect those current situations in which African Americans found themselves, and others are quite unique, no doubt owing to her privileged position in the African American community. The principle conclusions reached include the great benefits derived from doing this kind of research, as difficult and time-consuming as that may be, with the enhanced knowledge and appreciation of the heritage of African American physicians, and insights into American social history during this period.

  7. Bence-Jones protein - quantitative

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003597.htm Quantitative Bence-Jones protein test To use the sharing ... Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare ...

  8. Arthroscopically Assisted Modified Jones Procedure.

    PubMed

    Lui, Tun Hing

    2016-12-01

    The modified Jones procedure is the classic operative treatment of symptomatic clawed hallux. It is composed of transfer of the extensor hallucis longus tendon to the first metatarsal neck and fusion of the hallux interphalangeal joint. The purpose of this technical note is to report the technique of an arthroscopically assisted modified Jones procedure. This can be combined with other minimally invasive bone and soft-tissue procedures to correct all aspects of the complex cavus foot deformity.

  9. Jones nabs big DOE job

    SciTech Connect

    Setzer, S.W.; Rubin, D.K.

    1992-07-06

    This article is a review of the recent award of the engineering contract at Hanford to a joint venture of Duke Power and J. A. Jones Construction Services. The contract, worth an estimated $500M, is for a three-year period running through September 1995. Impact on the incumbent (ICF Kaiser) work force is expected to be minimal, with the majority of the personnel being retained by Duke/Jones.

  10. The House That Jones Built.

    ERIC Educational Resources Information Center

    Rist, Marilee C.

    1992-01-01

    Describes lifelong commitment of middle-school principal and major W.J. Jones to Coahoma, a small town in Mississippi Delta. Thanks to his efforts, town recently acquired a sewage system, blacktopped roads, and new housing (through Habitat for Humanity and World Vision). Although town elementary school fell victim to consolidation and children are…

  11. No More Indiana Jones Warehouses

    ERIC Educational Resources Information Center

    Pannapacker, William

    2012-01-01

    In "Raiders of the Lost Ark," Indiana Jones--perhaps the last heroic professor to appear in a major Hollywood film--survives a series of adventures involving spiders, snakes, treacherous colleagues, and countless Nazis who are determined to recover the ark of the covenant for their "Fuhrer." Apparently the ark has mystical powers. Ultimately,…

  12. No More Indiana Jones Warehouses

    ERIC Educational Resources Information Center

    Pannapacker, William

    2012-01-01

    In "Raiders of the Lost Ark," Indiana Jones--perhaps the last heroic professor to appear in a major Hollywood film--survives a series of adventures involving spiders, snakes, treacherous colleagues, and countless Nazis who are determined to recover the ark of the covenant for their "Fuhrer." Apparently the ark has mystical powers. Ultimately,…

  13. The Displacement of Mary Jones.

    ERIC Educational Resources Information Center

    McCaslin, Sharon

    1990-01-01

    Describes the experiences of Mary Jones as librarian at the University of Nebraska (1892-97), her resignation attributed to sex discrimination, the impact of her resignation on the library, and her subsequent positions at the University of Illinois, University of Iowa, and Los Angeles Public Library. A sidebar discusses women's career paths in the…

  14. The Jones Family's Culture of Literacy

    ERIC Educational Resources Information Center

    Johnson, Amy Suzanne

    2010-01-01

    This article considers the uses of literacy within the Jones family (all names are pseudonyms), an African American family who lives in the rural South of the United States. Drawing on life history data with three women in the Jones family--Harriet Jones (grandmother), Sally Harris (mother), and Lola Harris (granddaughter)--the author traces how…

  15. The Jones Family's Culture of Literacy

    ERIC Educational Resources Information Center

    Johnson, Amy Suzanne

    2010-01-01

    This article considers the uses of literacy within the Jones family (all names are pseudonyms), an African American family who lives in the rural South of the United States. Drawing on life history data with three women in the Jones family--Harriet Jones (grandmother), Sally Harris (mother), and Lola Harris (granddaughter)--the author traces how…

  16. Dyfrig Jones 1940”1989

    NASA Astrophysics Data System (ADS)

    Horne, Richard

    Dyfrig Jones, Head of the Space Plasma Physics Group at the British Antarctic Survey, died August 6, 1989.Dyfrig was born August 16, 1940, in the fishing village of Crwbin, Pembrokeshire, South Wales. He attended Cardigan Grammar School and went on to read physics at the University College of Wales, Aberystwyth, completing a Ph.D. in experimental physics in 1964 on interpreting ionospheric drift data. The skills he learned during his Ph.D. work, which entailed the design of radio and signal processing equipment and the development of new computer methods for signal correlation and spectral analysis, laid the foundation for his career.

  17. Doug Jones Home Improvement Information Sheet

    EPA Pesticide Factsheets

    Doug Jones Home Improvement (the Company) is located in Louisville, Kentucky. The settlement involves renovation activities conducted at property constructed prior to 1978, located in Louisville, Kentucky.

  18. The Immortality of Ms Jones

    PubMed Central

    Gallagher, Timothy

    2014-01-01

    When I began my medical student clinical rotations, I quickly became overwhelmed by feelings of inadequacy. While the doctors around me conjured appropriate diagnoses and treatment approaches, I fumbled with the only tools I possessed: my time and a smile. It was only when I met the patient Ms Jones that I came to understand the potential impact of these simple tools. My encouragement became part of her recovery process. She gave me the confidence to construct this ability of comforting patients into a small platform of confidence from which I could safely venture to educate patients or suggest treatments to residents. It could be something that I could reliably fall back on in times of doubt and something I could pass along to other people I met. PMID:25024247

  19. The immortality of Ms Jones.

    PubMed

    Gallagher, Timothy

    2014-07-01

    When I began my medical student clinical rotations, I quickly became overwhelmed by feelings of inadequacy. While the doctors around me conjured appropriate diagnoses and treatment approaches, I fumbled with the only tools I possessed: my time and a smile. It was only when I met the patient Ms Jones that I came to understand the potential impact of these simple tools. My encouragement became part of her recovery process. She gave me the confidence to construct this ability of comforting patients into a small platform of confidence from which I could safely venture to educate patients or suggest treatments to residents. It could be something that I could reliably fall back on in times of doubt and something I could pass along to other people I met.

  20. STS-98 Crew Interview: Tom Jones

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The STS-98 Mission Specialist Tom Jones is seen being interviewed. He answers questions about his inspiration to become an astronaut, his career path, and his training. He gives details on the mission's goals and significance, and the payload and hardware it brings to the International Space Station (ISS). Mr. Jones discusses his role in the mission's spacewalks and activities.

  1. Militant Motherhood: Labor's Mary Harris "Mother" Jones.

    ERIC Educational Resources Information Center

    Tonn, Mari Boor

    1996-01-01

    Uses "Mother Jones" to explore the link between labor union agitation and use of symbolic motherhood by female labor leaders. Argues that maternal aims such as physical protection helped empower oppressed mining audiences. Suggests that Jones's militant motherhood--realized through nondiscursive maternal practices and a…

  2. Jones Center Vocational/Academic Program (JCVA).

    ERIC Educational Resources Information Center

    Rydalch, Jeff

    This document provides information on the Jones Center Vocational/Academic Program of the Granite School District (Utah), the purpose of which is to maintain or reintegrate students who are potential high school dropouts or dropouts into appropriate educational alternatives. Its mission statement is followed by a list of program components,…

  3. 1. View along Jones Street showing S elevation. Central ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View along Jones Street showing S elevation. - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Paint & Coach Barn, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  4. 77 FR 41807 - Dow Jones & Company, Inc., Dow Jones Content Services Division, Including On-Site Workers From...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Dow Jones & Company, Inc., Dow Jones Content Services Division, Including On-Site Workers From Aerotek, Inc., Princeton, NJ; Generate, Inc., a Subsidiary of Dow Jones & Company, Inc., Boston, MA; Amended...

  5. Hydrophobicity in Lennard-Jones solutions.

    PubMed

    Ishizaki, Mario; Tanaka, Hideki; Koga, Kenichiro

    2011-02-14

    The analogue of the hydrophobic hydration is explored for Lennard-Jones solutions. The free energy of solvation and its temperature derivatives, both in the constant-pressure process and in the constant-volume process, are obtained numerically for a variety of the size and energy parameters for the solute-solvent Lennard-Jones potential. We identify in the parameter space a region in which the solvation is of hydrophobic character, with an understanding that hydrophobicity is characterized by both the solvation free energy being positive and the solvation process being exothermic. Such a region is found in each case of the isobaric and isochoric conditions and the region is seen to be much wider in the isochoric process than in the isobaric one. Its origin and implication are discussed.

  6. Crystals of binary Lennard-Jones solids

    NASA Astrophysics Data System (ADS)

    Middleton, Thomas F.; Hernández-Rojas, Javier; Mortenson, Paul N.; Wales, David J.

    2001-11-01

    We present crystalline structures for 60-, 256-, and 320-atom supercells of binary Lennard-Jones solids. These structures, based on cubic close packing, are much lower in energy than the disordered structures usually considered for this model glass former. We present a disconnectivity graph for a database of minima and transition states for the 320-atom system, which has been simplified using a grouping technique based on the canonical rate constants.

  7. Lennnard Jones Potential for Mesoscopic System

    NASA Astrophysics Data System (ADS)

    Taruna, Jutri

    2005-11-01

    The liquid-gas phase transition of a Lennard Jones system of N=500 particles is studied via Molecular Dynamics simulations. Rather than displaying a positive isothermal compressibility --- as is demanded of stable systems in the thermodynamic limit --- the system develops a ``Van der Waals loop'', namely, a region with negative isothermal compressibility. We use various observables as well as state-of-the-art computer renderings to elucidate the nature of this behavior.

  8. Test pilots 1952 - Walker, Butchart, and Jones

    NASA Technical Reports Server (NTRS)

    1952-01-01

    This photo shows test pilots, (Left-Right) Joseph A. Walker, Stanley P. Butchart and Walter P. Jones, standing in front of the Douglas D-558-II Skystreak, in 1952. These three test pilots at the National Advisory Committee for Aeronautics' High-Speed Flight Research Station probably were discussing their flights in the aircraft. Joe flew research flights on the D-558-I #3 (14 flights, first on June 29, 1951) investigating buffeting, tail loads, and longitudinal stability. He flew the D-558-II #2 (3 flights, first on April 29, 1955) and recorded data on lateral stability and control. He also made pilot check-out flights in the D-558-II #3 (2 flights, first on May 7, 1954). For fifteen years Walker served as a pilot at the Edwards flight research facility (today known as the National Aeronautics and Space Administration's Dryden Flight Research Center) on research flights as well as chase missions for other pilots on NASA and Air Force research programs. On June 8, 1966, he was flying chase in NASA's F-104N for the Air Force's experimental bomber, North American XB-70A, when he was fatally injured in a mid-air collision between the planes. Stan flew the D-558-I #3 (12 flights, first on October 19, 1951) to determine the dynamic longitudinal stability characteristics and investigations of the lateral stability and control. He made one flight in the D-558-II #3 on June 26, 1953, as a pilot check-out flight. Butchart retired from the NASA Dryden Flight Research Center at Edwards, California, on February 27, 1976, after a 25-year career in research aviation. Stan served as a research pilot, chief pilot, and director of flight operations. Walter P. Jones was a research pilot for NACA from the fall of 1950 to July 1952. He had been in the U.S. Air Force as a pilot before joining the Station. Jones flew the D-558-I #3 (5 flights, first on February 13, 1951) to study buffeting, tail loads and longitudinal stability. Jones made research flights on the D-558-II #3 ( 7 flights

  9. Test pilots 1952 - Walker, Butchart, and Jones

    NASA Technical Reports Server (NTRS)

    1952-01-01

    This photo shows test pilots, (Left-Right) Joseph A. Walker, Stanley P. Butchart and Walter P. Jones, standing in front of the Douglas D-558-II Skystreak, in 1952. These three test pilots at the National Advisory Committee for Aeronautics' High-Speed Flight Research Station probably were discussing their flights in the aircraft. Joe flew research flights on the D-558-I #3 (14 flights, first on June 29, 1951) investigating buffeting, tail loads, and longitudinal stability. He flew the D-558-II #2 (3 flights, first on April 29, 1955) and recorded data on lateral stability and control. He also made pilot check-out flights in the D-558-II #3 (2 flights, first on May 7, 1954). For fifteen years Walker served as a pilot at the Edwards flight research facility (today known as the National Aeronautics and Space Administration's Dryden Flight Research Center) on research flights as well as chase missions for other pilots on NASA and Air Force research programs. On June 8, 1966, he was flying chase in NASA's F-104N for the Air Force's experimental bomber, North American XB-70A, when he was fatally injured in a mid-air collision between the planes. Stan flew the D-558-I #3 (12 flights, first on October 19, 1951) to determine the dynamic longitudinal stability characteristics and investigations of the lateral stability and control. He made one flight in the D-558-II #3 on June 26, 1953, as a pilot check-out flight. Butchart retired from the NASA Dryden Flight Research Center at Edwards, California, on February 27, 1976, after a 25-year career in research aviation. Stan served as a research pilot, chief pilot, and director of flight operations. Walter P. Jones was a research pilot for NACA from the fall of 1950 to July 1952. He had been in the U.S. Air Force as a pilot before joining the Station. Jones flew the D-558-I #3 (5 flights, first on February 13, 1951) to study buffeting, tail loads and longitudinal stability. Jones made research flights on the D-558-II #3 ( 7 flights

  10. Zeros of Jones polynomials for families of knots and links

    NASA Astrophysics Data System (ADS)

    Chang, S.-C.; Shrock, R.

    2001-12-01

    We calculate Jones polynomials VL( t) for several families of alternating knots and links by computing the Tutte polynomials T( G, x, y) for the associated graphs G and then obtaining VL( t) as a special case of the Tutte polynomial. For each of these families we determine the zeros of the Jones polynomial, including the accumulation set in the limit of infinitely many crossings. A discussion is also given of the calculation of Jones polynomials for non-alternating links.

  11. 6. Historic American Buildings Survey Lester Jones, Photographer May 30, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Lester Jones, Photographer May 30, 1940. BRICKWORK DETAIL - NORTHWEST ELEVATION - Colonel William Whitley House, Stanford-Crab Orchard Pike, Stanford, Lincoln County, KY

  12. 2. Historic American Buildings Survey Lester Jones, Photographer March 2, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Lester Jones, Photographer March 2, 1940 GENERAL VIEW FROM SOUTHWEST - Fort Smith, Commissary Building, 100 South Garrison Avenue, Fort Smith, Sebastian County, AR

  13. 1. Historic American Buildings Survey Lester Jones, Photographer February 28, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer February 28, 1940 SLAVE HOSPITAL FROM THE SOUTHWEST - Melrose Plantation, Slave Hospital, State Highway 119, Melrose, Natchitoches Parish, LA

  14. 7. Historic American Buildings Survey, Lester Jones, Photographer August 21, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey, Lester Jones, Photographer August 21, 1940 EAST WALL, NORTHEAST ROOM, FIRST FLOOR. - Rock Castle, Indian Lake Road (Berry Lane), Hendersonville, Sumner County, TN

  15. 3. Historic American Buildings Survey Lester Jones, Photographer. July 31, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Lester Jones, Photographer. July 31, 1940 INTERIOR OF CHESTNUT STREET ENTRANCE - Wainwright Building, Seventh & Chestnut Streets, Saint Louis, Independent City, MO

  16. 1. Historic American Buildings Survey Russell Jones, Photographer June 1963 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Russell Jones, Photographer June 1963 SOUTHWEST VIEW - Abner Cloud House, Intersection of Canal Road & Reservoir Road Northwest, Washington, District of Columbia, DC

  17. 2. Historic American Buildings Survey Russell Jones, Photographer June 1963 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Russell Jones, Photographer June 1963 SOUTHEAST VIEW - Abner Cloud House, Intersection of Canal Road & Reservoir Road Northwest, Washington, District of Columbia, DC

  18. Historic American Buildings Survey Lester Jones, Photographer February 28, 1940 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Historic American Buildings Survey Lester Jones, Photographer February 28, 1940 "African House" SOUTH ELEVATION - Melrose Plantation, African House, State Highway 119, Melrose, Natchitoches Parish, LA

  19. Jones precoder for polarization mode dispersion compensation

    NASA Astrophysics Data System (ADS)

    Zhu, Zhenyu; Sadjadpour, Hamid R.; Blum, Rick S.; Andrekson, Peter A.; Li, Tiffany Jing

    2008-04-01

    A new electrical-domain precoder is proposed to mitigate polarization mode dispersion (PMD) in optical communications by modeling a PMD-dominant fiber optical channel using a single input multiple output (SIMO) channel. Employing a bank of finite impulse response filters and a polarization modulator, and using parameters derived from the Jones matrix representation of PMD, the proposed precoder efficiently adapts to the time-varying nature of PMD and simultaneously pre-equalizes both polarization modes at the transmitter. The transmitter-only structure avoids losing phase and polarization information due to the nonlinearity of the commonly used square law direct-detection receiver. Analysis is performed to evaluate the impact of channel mismatch due to feedback delay, channel estimation errors, and the impact of the finite length of the precoder filters. The analytical results are used to guide selection of the appropriate feedback rate for the adaptive system. Extensive simulation results confirm the efficiency of the proposed Jones precoder, and present it as an effective, low-cost replacement to the complicated, expensive optical-domain counter-parts.

  20. Freezing of Lennard-Jones-type fluids

    SciTech Connect

    Khrapak, Sergey A.; Chaudhuri, Manis; Morfill, Gregor E.

    2011-02-07

    We put forward an approximate method to locate the fluid-solid (freezing) phase transition in systems of classical particles interacting via a wide range of Lennard-Jones-type potentials. This method is based on the constancy of the properly normalized second derivative of the interaction potential (freezing indicator) along the freezing curve. As demonstrated recently it yields remarkably good agreement with previous numerical simulation studies of the conventional 12-6 Lennard-Jones (LJ) fluid [S.A.Khrapak, M.Chaudhuri, G.E.Morfill, Phys. Rev. B 134, 052101 (2010)]. In this paper, we test this approach using a wide range of the LJ-type potentials, including LJ n-6 and exp-6 models, and find that it remains sufficiently accurate and reliable in reproducing the corresponding freezing curves, down to the triple-point temperatures. One of the possible application of the method--estimation of the freezing conditions in complex (dusty) plasmas with ''tunable'' interactions--is briefly discussed.

  1. On E.D. Jones' MICROCOSMOLOGY

    SciTech Connect

    Noyes, H. Pierre

    2003-01-08

    By taking seriously the limits on observability which come from combining relativistic quantum mechanics with general relativity, Ed Jones has shown that the current measurements of the cosmological constant density {Omega}{sub {Lambda}} {approx} 0.7 imply that the temperature scale at which it becomes possible to discuss cosmological models is {approx} 5 Tev (5.8 x 10{sup 16} K). This is self-consistent with the assumption that the number of Planck masses which make some sort of ''phase transition'' to this state is N{sub Pk} {approx} 4 x 10{sup 61}. We review Jones' argument and the bit-string physics calculation which gives the baryon-photon ratio at nucleosynthesis as {approx} 2/256{sup 4}, the dark matter-baryon ratio as {approx} 12.7, and hence {Omega}{sub m} {approx} 0.3, in agreement with current observations. Accepting these values for the two energy densities {Omega}{sub {Lambda}} + {Omega}{sub m} {approx} 1 in accord with recent analyses of fluctuations in the CMB showing that space is flat to about 6%. We conclude that experiments with particle accelerators in the 5-10 Tev range must either show that current theory can adequately describe the currently observed structure of our universe or force us to revise our ideas about physics at a very fundamental level.

  2. Robert T. Jones, One of a Kind

    NASA Astrophysics Data System (ADS)

    Vincenti, Walter G.

    2005-01-01

    His contemporaries saw R.T. Jones as one of the notably creative aerodynamicists of the twentieth century. This essay reviews his remarkable life and career, including his years as a farm-country boy, college dropout, and fledgling airplane designer in Missouri, his time as an elevator operator and self-directed student in Washington, D.C., and his long professional career as an aerodynamicist at the Langley and Ames Aeronautical Laboratories and Stanford University. The focus in his career is on his fundamental discovery of the benefits of sweepback for the wings of high-speed airplanes. This includes speculation about his highly intuitive thought processes in arriving at his creative ideas. I also give an account of his work on blood flow and the mechanical heart, his avocational accomplishments as a maker of telescopes and violins, and his philosophical interest in human affairs.

  3. Chemical Potential of a Lennard Jones Fluid

    NASA Astrophysics Data System (ADS)

    Celebonovic, V.

    2010-12-01

    The aim of this paper is to present results of analytical calculation of chemical potential of a Lennard Jones (LJ) fluid performed in two ways: by using the thermodynamical formalism and the formalism of statistical mechanics. The integration range is divided into two regions. In the small distance region, which is r≤σ in the usual notation, the integration range had to be cut off in order to avoid the occurence of divergences. In the large distance region, the calculation is technically simpler. The calculation reported here will be useful in all kinds of studies concerning phase equilibrium in a LJ fluid. Interesting kinds of such systems are the giant planets and the icy satellites in various planetary systems, but also the (so far) hypothetical quark stars.

  4. Astronaut Thomas Jones opens food package on middeck

    NASA Image and Video Library

    1994-04-10

    STS059-14-004 (9-20 April 1994) --- On the Space Shuttle Endeavour's middeck astronaut Thomas D. Jones, mission specialist, cuts open a package of food as he prepares for mealtime. Jones was joined by five other NASA astronauts aboard Endeavour for the STS-59 mission.

  5. CATABOLIC ORIGIN OF A BENCE JONES PROTEIN FRAGMENT

    PubMed Central

    Cioli, D.; Baglioni, C.

    1968-01-01

    Gel filtration analysis of the urinary proteins of some patients with myeloma has shown the presence of "fragments" of Bence Jones proteins which correspond to the variable half of these proteins. Experiments have been carried out to establish the origin of a "fragment" observed in a patient who excreted a large amount of this protein. Labeled homologous Bence Jones protein has been injected into this and other control patients. Excretion of labeled "fragment" has been observed in all. Analysis by peptide mapping and radio-autography of this labeled "fragment" isolated from the urine showed that the invariable half of the Bence Jones protein was not excreted; it seemed thus likely that the invariable half was metabolized to small peptides and free amino acids. A labeled Bence Jones protein which was excreted without any accompanying "fragment" was injected into the patient who excreted large amounts of "fragment." No excretion of labeled "fragment" was observed. It was thus concluded that the property of being degraded to "fragment" is characteristic of some "fragile" Bence Jones proteins and is not determined by the patient. Incubation with serum or urine of the "fragile" Bence Jones protein failed to produce any "fragment." "Fragments" of Bence Jones proteins are thus most likely formed during excretion of these proteins through the kidney and are products of the catabolism of Bence Jones proteins. PMID:5666962

  6. Longer term rest from grazing: a response to Jones & Carter

    USDA-ARS?s Scientific Manuscript database

    Jones and Carter (this issue) in a response to Davies et al. (2014) misrepresent the original article and other articles, develop arguments not supported by scientific literature, and ignore literature counter to their opinion. Most peculiar, Jones and Carter incorrectly state that Davies et al. co...

  7. 1. View along Jones Street showing (1 to r) S ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View along Jones Street showing (1 to r) S elevation of Paint & Coach Shop, Pattern Room, Lumber Storage, Engine and Boiler House. - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Engine Boiler & Pattern Building, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  8. Willie Jones: The Alternate View of a North Carolina Antifederalist.

    ERIC Educational Resources Information Center

    Ragan, Fred D.

    The paper traces the life of the 18th century North Carolinian planter Willie Jones and his transformed political stance from traditional commitment to the Crown to a new constitutional faith in republicanism. Jones' political career and struggles are noted through the Revolutionary era and the controversy of centralized versus decentralized…

  9. Obituary: Frank Culver Jones, 1932-2007

    NASA Astrophysics Data System (ADS)

    Ormes, Johnathan F.; Streitmatter, Robert E.

    2007-12-01

    Frank C. Jones, an emeritus theoretical physicist at NASA, died May 2, 2007 at age 74 after a struggle with a rare form of cancer. He died at his home in Silver Spring, Maryland, surrounded by his family. Frank was born July 30, 1932 in Fort Worth, Texas, the oldest of three boys. His parents were Kenneth Hugh and Nancy Culver Jones. Frank's father was a lawyer, and his grandfather was a Methodist minister. Frank graduated from Rice University in 1954 and earned a master's degree in 1955 and a doctorate in 1961, both in physics, from the University of Chicago. He did his graduate work with Prof. John Simpson. Dr. Jones began his professional career as an instructor in physics at Princeton University before joining NASA's Goddard Space Flight Center in 1963 as a National Research Council associate. He subsequently became a member of the Theory Division and the Laboratory for High Energy Astrophysics. His area of expertise was the origin, transport, and electromagnetic interactions of cosmic rays. His particular focus was the stochastic physics related to the diffusion of particles in random fields, plasma turbulence, and the shock acceleration of charged particles in collisionless plasmas. From 1993 to 1995, Frank was head of Goddard's Theoretical High Energy Astrophysics Office and continued to serve as Head of the Theory group. In 2003 he served as Acting Chief of the Laboratory for High Energy Astrophysics. He retired in 2005 and continued his affiliation with NASA as an emeritus scientist at Goddard until his death. As a youngster, Frank showed the signs of curiosity and initiative that indicated he might become an experimentalist. At the memorial service for Frank, his brother related the stories of how Frank had rigged a hidden microphone to play through the family television as his brother courted a young woman on the front porch swing, and how one of Frank's early chemistry experiments caused all the family silverware to turn black. Although Frank started

  10. 77 FR 19718 - Dow Jones & Company, Inc., Dow Jones Content Services Including On-Site Workers From Aerotek, Inc...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Dow Jones & Company, Inc., Dow Jones Content Services Including On-Site Workers From Aerotek, Inc., Princeton, NJ; Amended Certification Regarding Eligibility To Apply for Worker Adjustment Assistance In accordance...

  11. Transport theory for the Lennard-Jones dense fluid

    SciTech Connect

    Karkheck, J.; Stell, G.; Xu, J.

    1988-11-01

    A kinetic theory for a fluid of particles interacting via a pair potential with hard-core plus truncated tail is described and used to derive a transport theory for the Lennard-Jones fluid as well as the square-well fluid. Numerical results for shear viscosity, thermal conductivity, and the self-diffusion coefficient are given for the Lennard-Jones fluid and compared with simulation and experimental results. Our Lennard-Jones theory proves quantitatively useful over a wide range of states.

  12. Bence Jones proteins and light chains of immunoglobulins. XI. A transient Bence Jones-related protein associated with corticosteroid therapy.

    PubMed Central

    Solomon, A; McLaughlin, C L; Capra, J D

    1975-01-01

    Urine specimens from patients with multiple myeloma and Bence Jones proteinuria frequently contain low molecular weight proteins which correspond either to the amino-terminal, variant half (VL) or to the carboxyl-terminal, constant half (CL) of the Bence Jones protein. Analyses of urine specimens from such patients who had received high doses of corticosteroids as part of their treatment regimen revealed that concomitantly with a decrease in Bence Jones protein excretion was the appearance of a low molecular weight protein related to the Bence Jones protein but not identical to the VL or to the CL. Analyses of daily urine specimens obtained from one such patient over an extended time period revealed that a reproducible chain of events occurred during a treatment regimen which included oral administration of 75 mg of prednisone daily for 7 consecutive days. The amount of Bence Jones protein excreted decreased progressively, and by the 5th day was usually less than 10% of the pretreatment value. The urine specimen obtained on the 6th day of treatment was virtually devoid of Bence Jones protein but contained a newly appearing protein whose electrophoretic mobility was distinct from that of the Bence Jones protein or its VL or CL. Cessation of corticosteroid therapy resulted in a prompt disappearance of the new protein and in a progressive increase in the amount of Bence Jones protein excreted. The new protein was isolated from the urine of this patient and was purified for comparative studies with Bence Jones protein and with the VL and CL prepared by specific enzymatic cleavage of the Bence Jones protein. These studies revealed that the new protein was most related antigenically to the CL, but could be distinguished immunochemically from the CL. This new protein, a component found in vivo related to the constant half of the light polypeptide chain, was designated CL, and was structurally 25 amino acid residues longer than the CL, that is, the amino-terminus of the

  13. 6. Historic American Buildings Survey Lester Jones, Photographer July 7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Lester Jones, Photographer July 7, 1940 SERVANT'S STAIRWAY - Colonel William Oliver Anderson House, Civil War Battle of Lexington State Park, Lexington, Lafayette County, MO

  14. ISS Update: Status of Space Act Agreement with Brad Jones

    NASA Image and Video Library

    NASA Public Affairs Officer Kyle Herring interviews Brad Jones, Deputy Manager, Partner Integration Office – Commercial Crew Program, about the Space Act Agreement. Questions? Ask us on Twitter ...

  15. 14. Historic American Buildings Survey Russell Jones, Photographer June 1963 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Historic American Buildings Survey Russell Jones, Photographer June 1963 DOOR DETAIL From Dining Room to Garden - Timothy Caldwell House, 2017 "Eye" Street Northwest, Washington, District of Columbia, DC

  16. 1. Historic American Buildings Survey Russell Jones, Photographer March 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Russell Jones, Photographer March 1959 FRONT (SOUTH) ELEVATION FROM THE SOUTH EAST. - Justice Horace Gray House, 1601 Eye Street Northwest, Washington, District of Columbia, DC

  17. 15. Historic American Buildings Survey Russell Jones, Photographer June 1963 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Historic American Buildings Survey Russell Jones, Photographer June 1963 WINDOW DETAIL Rear Main House, First Floor - Timothy Caldwell House, 2017 "Eye" Street Northwest, Washington, District of Columbia, DC

  18. STS-80 Mission Specialist Thomas Jones in White Room

    NASA Technical Reports Server (NTRS)

    1996-01-01

    STS-80 Mission Specialist Thomas D. Jones prepares to enter the Space Shuttle Columbia at Launch Pad 39B, with assistance from white room closeout crew members (from left) Rick Welty and Bob Saulnier.

  19. 12. Historic American Buildings Survey, Stanley Jones, Photographer July 6, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Historic American Buildings Survey, Stanley Jones, Photographer July 6, 1936, copied from portrait, PORTRAIT OF WILLIAM HENRY 3RD, OWNER OF HENRY GUN FACTORY. - Henry Gun Factory, Belfast, Northampton County, PA

  20. 11. Historic American Buildings Survey, Stanley Jones, Photographer July 6, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic American Buildings Survey, Stanley Jones, Photographer July 6, 1936, copied from portrait, PORTRAIT OF WILLIAM HENRY, INVENTOR OF HENRY GUN. - Henry Gun Factory, Belfast, Northampton County, PA

  1. 2. Historic American Buildings Survey Lester Jones, Photographer. Copied from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Lester Jones, Photographer. Copied from old photograph July 5, 1940 VIEW FROM SOUTH, PRIOR TO 1925 - Houston Tavern, Arrow Rock State Park, Arrow Rock, Saline County, MO

  2. 1. Historic American Buildings Survey Lester Jones, Photographer. Copied from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer. Copied from old photograph July 5, 1940 VIEW FROM NORTHWEST, PRIOR TO 1925 - Houston Tavern, Arrow Rock State Park, Arrow Rock, Saline County, MO

  3. 6. Historic American Buildings Survey Lester Jones, Photographer. Copied from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Lester Jones, Photographer. Copied from old photograph July 5, 1940 WINDOW DETAIL, PRIOR TO 1925 - Houston Tavern, Arrow Rock State Park, Arrow Rock, Saline County, MO

  4. STS-80 Mission Specialist Thomas Jones in White Room

    NASA Technical Reports Server (NTRS)

    1996-01-01

    STS-80 Mission Specialist Thomas D. Jones prepares to enter the Space Shuttle Columbia at Launch Pad 39B, with assistance from white room closeout crew members (from left) Rick Welty and Bob Saulnier.

  5. 3. Historic American Buildings Survey Lester Jones, Photographer August 24, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Lester Jones, Photographer August 24, 1940 SPIRAL STAIRWAY - Shaker Centre Family Trustees' Office, South side of Village Road, North of U.S. Route 68 & State Route 33 intersection, Shakertown, Mercer County, KY

  6. 1. Historic American Buildings Survey Lester Jones, Photographer February 28, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer February 28, 1940 VIEW FROM THE SOUTH-WEST - Church of the Immaculate Conception, 145 Church Street, Natchitoches, Natchitoches Parish, LA

  7. 6. Watchman Robert 'Jerry' Jones at Camp Dyer. Photographer James ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Watchman Robert 'Jerry' Jones at Camp Dyer. Photographer James Dix Schuyler, 1903. Source: Schuyler report. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  8. 6. Historic American Buildings Survey Russell Jones, Photographer January 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Russell Jones, Photographer January 1959 WINDOW DETAIL - REAR FACADE (S. W. CORNER), 2nd FLOOR - Forrest-Marbury House, 3350 M Street Northwest, Washington, District of Columbia, DC

  9. 5. Historic American Buildings Survey Russell Jones, Photographer January 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey Russell Jones, Photographer January 1959 CHIMNEY DETAIL, SHOWING CAST_IRON CAP. - Forrest-Marbury House, 3350 M Street Northwest, Washington, District of Columbia, DC

  10. 1. Historic American Buildings Survey Lester Jones, Photographer. October 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer. October 1, 1940. VIEW FROM NORTHEAST - Fort de Chartres, Powder Magazine, Fort de Chartres State Park, Prairie du Rocher, Randolph County, IL

  11. 2. Historic American Buildings Survey Lester Jones, Photographer. October 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Lester Jones, Photographer. October 1, 1940. VIEW FROM SOUTHWEST - Fort de Chartres, Powder Magazine, Fort de Chartres State Park, Prairie du Rocher, Randolph County, IL

  12. 1. Historic American Buildings Survey Lester Jones, Photographer October 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer October 1, 1940. VIEW FROM SOUTHEAST - Fort de Chartres, East Barracks (Foundations), Fort de Chartres State Park, Prairie du Rocher, Randolph County, IL

  13. 1. Historic American Buildings Survey, Lester Jones, Photographer. October 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, Lester Jones, Photographer. October 1, 1940. VIEW FROM NORTHWEST - Fort de Chartres, Officers' Quarters (Foundations), Fort de Chartres State Park, Prairie du Rocher, Randolph County, IL

  14. 1. Historic American Buildings Survey Lester Jones, Photographer October 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer October 1, 1940. VIEW FROM NORTHWEST - Fort de Chartres, West Barracks (Foundations), Fort de Chartres State Park, Prairie du Rocher, Randolph County, IL

  15. 1. Historic American Buildings Survey Lester Jones, Photographer. October 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer. October 1, 1940. VIEW FROM NORTHEAST - Fort de Chartres, Commandant's Quarters (Foundations), Fort de Chartres State Park, Prairie du Rocher, Randolph County, IL

  16. 1. Historic American Buildings Survey Lester Jones, Photographer June 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer June 1, 1940 VIEW FROM SOUTHWEST - Morrison College, Transylvania University, West Third Street, between Upper Street & Broadway, Lexington, Fayette County, KY

  17. 2. Historic American Buildings Survey Lester Jones, Photographer June 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Lester Jones, Photographer June 1, 1940 VIEW FROM NORTH - Morrison College, Transylvania University, West Third Street, between Upper Street & Broadway, Lexington, Fayette County, KY

  18. 8. May 1974. BASE AND FLYWHEEL. Jones & Laughlin ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. May 1974. BASE AND FLYWHEEL. - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

  19. 7. Historic American Buildings Survey Lester Jones, Photographer May 29, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey Lester Jones, Photographer May 29, 1940. SUNDIAL With motto: 'Look to your laws rather than progenitors for inheritance.' - Samuel Taylor House, Chatham Pike, Harrodsburg, Mercer County, KY

  20. Astronaut Thomas Jones monitors cameras on targets of opportunity

    NASA Image and Video Library

    1994-04-10

    STS059-09-021 (9-20 April 1994) --- Astronaut Thomas D. Jones, mission specialist, monitors a number of cameras fixed on targets of opportunity as the Space Shuttle Endeavour orbits Earth. Jones is one of six NASA astronauts supporting the week and half Space Radar Laboratory (SRL-1) mission. He has been assigned as payload commander for SRL-2, scheduled to fly later this year.

  1. HOT METAL BRIDGE (NOTE: BUILDERS: JONES AND LAUGHLIN STEEL CA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HOT METAL BRIDGE (NOTE: BUILDERS: JONES AND LAUGHLIN STEEL CA. 1890), SOUTH PORTAL. THREE PIN CONNECTED CAMELBACK TRUSS SPANS, ONE SKEWED THROUGH TRUSS SPAN ON NORTH SIDE TRUSS BRIDGE, EAST OF HOT METAL BRIDGE BUILT BY AMERICAN BRIDGE COMPANY CA. 1910. (RIVETED MULTI-SPAN TRUSS). - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

  2. Lyapunov instabilities of Lennard-Jones fluids.

    PubMed

    Yang, Hong-liu; Radons, Günter

    2005-03-01

    Recent work on many-particle systems reveals the existence of regular collective perturbations corresponding to the smallest positive Lyapunov exponents (LEs), called hydrodynamic Lyapunov modes. Until now, however, these modes have been found only for hard-core systems. Here we report results on Lyapunov spectra and Lyapunov vectors (LVs) for Lennard-Jones fluids. By considering the Fourier transform of the coordinate fluctuation density u((alpha)) (x,t) , it is found that the LVs with lambda approximately equal to 0 are highly dominated by a few components with low wave numbers. These numerical results provide strong evidence that hydrodynamic Lyapunov modes do exist in soft-potential systems, although the collective Lyapunov modes are more vague than in hard-core systems. In studying the density and temperature dependence of these modes, it is found that, when the value of the Lyapunov exponent lambda((alpha)) is plotted as function of the dominant wave number k(max) of the corresponding LV, all data from simulations with different densities and temperatures collapse onto a single curve. This shows that the dispersion relation lambda((alpha)) vs k(max) for hydrodynamical Lyapunov modes appears to be universal for the low-density cases studied here. Despite the wavelike character of the LVs, no steplike structure exists in the Lyapunov spectrum of the systems studied here, in contrast to the hard-core case. Further numerical simulations show that the finite-time LEs fluctuate strongly. We have also investigated localization features of LVs and propose a length scale to characterize the Hamiltonian spatiotemporal chaotic states.

  3. Multi-contrast imaging of human posterior eye by Jones matrix optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Yasuno, Yoshiaki

    2017-04-01

    A multi-contrast imaging of pathologic posterior eyes is demonstrated by Jones matrix optical coherence tomography (Jones matrix OCT). The Jones matrix OCT provides five tomographies, which includes scattering, local attenuation, birefringence, polarization uniformity, and optical coherence angiography, by a single scan. The hardware configuration, algorithms of the Jones matrix OCT as well as its application to ophthalmology is discussed.

  4. NEWS: John Goronwy Jones (1920-1999)

    NASA Astrophysics Data System (ADS)

    Jennison, Brenda M.

    2000-05-01

    John Goronwy Jones Gron Jones, as he was known to all, was a champion of Physics Education and his death, shortly before his eightieth birthday, robbed physics teachers of a colleague who fought many battles on their behalf. He was not shy of taking issue with anyone in authority who might be putting forward policies which would harm his great love: Physics Education and Physics Teaching. His photograph shows a man with an impish grin, looking friend and foe alike straight in the eye, before delivering the death blow to an argument which was founded on less than common sense. At other times he would listen patiently to the woes of colleagues before offering them fatherly/grandfatherly advice so that whoever was on the receiving end would go away feeling better for the encounter. Gron was born in Swansea and educated at Lewis Boys Grammar School in Glamorgan before entering University College Cardiff first of all as a mathematician before graduating in Physics in 1941. After his war service in the RAF, working on signals and radar development, he returned to do an MSc in X-ray crystallography before completing a PGCE in Bristol. What then passed for teacher training in all institutions left him wary of returning to train teachers himself but after 14 years spent teaching physics in three schools he returned to Cardiff and began a 25 year career in teacher training. He and his two colleagues, Clifford Othen (chemistry) and Douglas Hillier (biology) built up the Cardiff Science Centre as a focus for initial and in-service science teacher training in South Wales. The triumvirate was well known and a power to be reckoned with. They created links between the University Science Departments and the Schools. Gron knew the local schools and their physics teachers intimately. Cardiff became a focus for science education both nationally and internationally. He was a frequent attender at both ICPE (International Commission for Physics Education) and GIREP (International Physics

  5. Flight into sanity. Jones's allegation of Ferenczi's mental deterioration reconsidered.

    PubMed

    Bonomi, C

    1999-06-01

    In 'The Life and Work of Sigmund Freud', Volume III, Ernest Jones explained Ferenczi's final contributions as the product of a mental deterioration based on a progressive psychosis. Erich Fromm collected various testimonies by witnesses of Ferenczi's last years, all contrasting with Jones's assertions, and challenged Jones's manner of writing history. However, since Fromm was himself a dissident, and his witnesses were pupils, relatives or friends of Ferenczi's, they were discarded as 'partisans'. The present study aims at reconsidering the question of Ferenczi's insanity on the basis of many unpublished documents. The consulted documents do not support Jones's allegation of Ferenczi's insanity. At the same time, they show that Jones's allegation was not a one-man fabrication, but reflected a shared belief, eliciting many questions about the nature of this belief, the lack of scrutiny that characterised its spreading, and its possible function within the psychoanalytic community. It is suggested that Ferenczi's personality and teaching, especially his emphasis on the need to accept the patient's criticism, contrasted with the dominant conception of psychoanalysis, based on the analyst's infallibility.

  6. The Lester-Jones tube and scuba diving.

    PubMed

    Mani, Navin; de Carpentier, John

    2009-01-01

    Insertion of a Lester-Jones tube remains the standard treatment for epiphora secondary to canalicular obstruction. We report on a patient requiring removal of his correctly working Lester-Jones tube to allow him to continue his hobby of scuba diving. This particular complication of the Lester-Jones tube has never previously been reported in the literature. Patients with Lester-Jones tubes are unable to perform the valsalva manoeuvre. The valsalva manoeuvre involves blowing the nose against occluded nostrils resulting in a raised pressure in the nose and post-nasal space which is transmitted via the eustachian tubes to the middle ear. The ability to perform a successful valsalva manoeuvre is a prerequisite of scuba diving to equalise middle ear pressure. Inability to equalise middle ear pressure can lead to barotrauma, including pain, rupture of the tympanic membrane and labyrinthine fistula. We recommend that when planning the insertion of a Lester-Jones tube it is wise to enquire whether the patient undertakes scuba diving. If the patient prefers to scuba dive raher than have control of their epiphora, the surgery should be deferred until the patient gives up diving.

  7. Dr. Howard Jones, Jr. (1910-2015): In Memoriam

    PubMed Central

    Oehninger, S.; Kruger, T.F.

    2015-01-01

    We honor the life of Howard W. Jones, Jr., MD, 104, a pioneer and visionary in reproductive medicine, a dedicated mentor, internationally renowned gynecological surgeon, and the father of in vitro fertilization IVF) in the United States. Dr. Jones founded the Jones Institute for Reproductive Medicine, in Norfolk, Virginia, at Eastern Virginia Medical School, in 1983. Today, IVF has grown exponentially not only in its direct application but also in the development of newer techniques would have been unimaginable a couple of decades ago. Throughout the years Dr. Howard has been a teacher and a mentor to many around the world. To us he also was a friend, a supporter at the time of difficult decisions, someone who would inspire hope, ignite the imagination, and instill a love of learning and untangling some of the complexities of the field, even of the human condition. His leadership, vision, knowledge, enthusiasm and inquisitive mind will be missed.

  8. Nuclear-magnetic-resonance quantum calculations of the Jones polynomial

    PubMed Central

    Marx, Raimund; Fahmy, Amr; Kauffman, Louis; Lomonaco, Samuel; Spörl, Andreas; Pomplun, Nikolas; Schulte-Herbrüggen, Thomas; Myers, John M.; Glaser, Steffen J.

    2011-01-01

    The repertoire of problems theoretically solvable by a quantum computer recently expanded to include the approximate evaluation of knot invariants, specifically the Jones polynomial. The experimental implementation of this evaluation, however, involves many known experimental challenges. Here we present experimental results for small-scale approximate evaluation of the Jones polynomial by nuclear magnetic resonance (NMR); in addition, we show how to escape from the limitations of NMR approaches that employ pseudopure states. Specifically, we use two spin-1/2 nuclei of natural abundance chloroform and apply a sequence of unitary transforms representing the trefoil knot, the figure-eight knot, and the Borromean rings. After measuring the nuclear spin state of the molecule in each case, we are able to estimate the value of the Jones polynomial for each of the knots. PMID:21461143

  9. Zeros of the Jones polynomials for families of pretzel links

    NASA Astrophysics Data System (ADS)

    Jin, Xian'an; Zhang, Fuji

    2003-10-01

    In this paper, a general method for computing the Tutte polynomial of the subdivision of a graph is explained. As an application to the subdivision of sheaf graph which consists of two vertices joined by some parallel edges, we obtain the explicit expressions of the Jones polynomials for some families of the pretzel links. Motivated by the work of Chang and Shrock, we investigate the zeros distribution of its Jones polynomial for each family when the number of crossings goes to infinity, and generalize some of their results.

  10. Jones and Polansky in U.S. Lab

    NASA Image and Video Library

    2001-02-07

    STS098-355-001 (7-20 February 2001) --- Astronauts Thomas D. Jones and Mark L. Polansky, STS-98 mission specialists, are photographed during their sleep shift in the newly-attached Destiny laboratory on the International Space Station (ISS).

  11. Contextual view of Fyffe Avenue between Jones and Boone Drives. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Contextual view of Fyffe Avenue between Jones and Boone Drives. ASA office (U.S. Border Control Environmental Office Building no. 317) is shown at center. Camera facing east. - Naval Supply Annex Stockton, Rough & Ready Island, Stockton, San Joaquin County, CA

  12. 'Jones Hybrid' hickory: A case study in Carya curation

    USDA-ARS?s Scientific Manuscript database

    'Jones Hybrid' hickory is an accession in the National Collection of Genetic Resources for Pecans and Hickories that was inherited with little information concerning its origination, its identity or its characteristics. It has been phenotypically and genetically profiled and is described here. Tha...

  13. Jones works with the PDGF during EVA 2

    NASA Image and Video Library

    2001-02-07

    STS098-339-008 (7-20 February 2001) --- Anchored to a restraint device on the end of the shuttle’s remote manipulator system (RMS) robot arm, astronaut Thomas D. Jones, mission specialist, works with the Power and Data Grapple Fixture (PDGF) in the cargo bay of the Space Shuttle Atlantis.

  14. AERIAL VIEW, LOOKING NORTHWEST TOWARDS JONES VALLEY FROM THE CREST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AERIAL VIEW, LOOKING NORTHWEST TOWARDS JONES VALLEY FROM THE CREST OF RED (CALLED RUFFNER) MOUNTAIN AND THE CITY OF BIRMINGHAM (TOP), WITH ABANDONED SLOSS CO. LIMESTONE QUARRIES (CENTER) AND RIGHT-OF-WAY OF THE L. & N. BIRMINGHAM MINERAL RAILROAD (LEFT CENTER TO BOTTOM RIGHT). - Ruffner Red Ore Mine, North of I-20 at Madrid Exit, Birmingham, Jefferson County, AL

  15. Edward Burne-Jones' Heavenly Conception: A Biblical Cosmos

    NASA Astrophysics Data System (ADS)

    Cheney, L. D. G.

    2016-01-01

    Edward Burne-Jones was a Pre-Raphaelite artist and designer, who collaborated with William Morris on many decorative arts (stained glass windows, book illustrations, ceramic and tapestry designs). He was a founding partner in the firm Morris, Marshall, Faulkner & Company. Burne-Jones composed The Days of Creation between 1870 and 1876 for the Morris firm. These paintings were executed in gouache and gold paint, and cartoons were made for tile and in stained glass, for the Church of St. Editha at Tamworth in Staffordshire. Burne-Jones' creation was highly praised and elegantly described by Oscar Wilde: “The picture is divided into six compartments, each representing a day in the Creation of the World, under the symbol of an angel holding a crystal globe, within which is shown the work of a day.” This paper will examine how Burne-Jones visualized an unusual celestial creation where angels holding magical spheres unveil the divine manifestation for the creation of a terrestrial realm. He created a cosmic utopia of the natural world.

  16. Birefringence of Cellotape: Jones Representation and Experimental Analysis

    ERIC Educational Resources Information Center

    Belendez, Augusto; Fernandez, Elena; Frances, Jorge; Neipp, Cristian

    2010-01-01

    In this paper, we analyse a simple experiment to study the effects of polarized light. A simple optical system composed of a polarizer, a retarder (cellotape) and an analyser is used to study the effect on the polarization state of the light which impinges on the setup. The optical system is characterized by means of a Jones matrix, and a simple…

  17. Thermal conductivity of the Lennard-Jones chain fluid model

    NASA Astrophysics Data System (ADS)

    Galliero, Guillaume; Boned, Christian

    2009-12-01

    Nonequilibrium molecular dynamics simulations have been performed to estimate, analyze, and correlate the thermal conductivity of a fluid composed of short Lennard-Jones chains (up to 16 segments) over a large range of thermodynamic conditions. It is shown that the dilute gas contribution to the thermal conductivity decreases when the chain length increases for a given temperature. In dense states, simulation results indicate that the residual thermal conductivity of the monomer increases strongly with density, but is weakly dependent on the temperature. Compared to the monomer value, it has been noted that the residual thermal conductivity of the chain was slightly decreasing with its length. Using these results, an empirical relation, including a contribution due to the critical enhancement, is proposed to provide an accurate estimation of the thermal conductivity of the Lennard-Jones chain fluid model (up to 16 segments) over the domain 0.8≤T∗≤6 and 0≤ρ∗≤1 . Additionally, it has been noted that all reduced thermal conductivity values of the Lennard-Jones chain fluid model merge on the same “universal” curve when plotted as a function of the excess entropy. Furthermore, it is shown that the reduced configurational thermal conductivity of the Lennard-Jones chain fluid model is approximately proportional to the reduced excess entropy for all fluid states and all chain lengths.

  18. 7. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT ELEVATION - 122 (LEFT) 124 (RIGHT) - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  19. 2. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (EAST) ELEVATION - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  20. 3. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (NORTH) ELEVATION - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  1. 1. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (SOUTH) ELEVATION. 600 (LEFT) 602 (RIGHT) - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  2. 9. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (WEST) ELEVATION FROM THE N.W. - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  3. 1. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (WEST) ELEVATION - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  4. 21. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. Historic American Buildings Survey Russell Jones, Photographer April 1959 REAR (EAST) ELEVATION FROM THE N. E. - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  5. 19. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Historic American Buildings Survey Russell Jones, Photographer April 1959 WINDOW DETAIL - 132 - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  6. 4. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (SOUTH) ELEVATION - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  7. 6. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Russell Jones, Photographer April 1959 ENTRY - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  8. 3. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (SOUTH) ELEVATION. 324 (LEFT) 326 (RIGHT) - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  9. 8. Historic American Buildings Survey Russell Jones, Photographer March 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey Russell Jones, Photographer March 1959 DETAIL - 2nd AND 3rd FLOOR WINDOWS, SOUTH ELEVATION - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  10. 4. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey Russell Jones, Photographer April 1959 ENTRY, #324 - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  11. 1. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT ELEVATION, 156 (LEFT) 158 (RIGHT) - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  12. 2. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Russell Jones, Photographer April 1959 EAST CENTER SECTION OF GROUP FROM THE NORTH - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  13. 5. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey Russell Jones, Photographer April 1959 WEST END OF GROUP FROM THE NORTH - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  14. 3. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Russell Jones, Photographer April 1959 WEST CENTER SECTION OF GROUP FROM THE NORTH - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  15. 6. Historic American Buildings Survey Russell Jones, Photographer March 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Russell Jones, Photographer March 1959 SOUTH ELEVATION FROM THE SOUTH EAST - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  16. 7. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey Russell Jones, Photographer April 1959 EAST ELEVATION FROM THE N. E. - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  17. 14. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (WEST) ELEVATION - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  18. 2. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT ELEVATION. 306 (LEFT), 308 (RIGHT) - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  19. 5. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (SOUTH) ELEVATION - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  20. 6. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (SOUTH) ELEVATION 808 (LEFT) 810 (RIGHT) - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  1. 9. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Historic American Buildings Survey Russell Jones, Photographer April 1959 GENERAL VIEW FROM THE EAST - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  2. 5. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (EAST) ELEVATION - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  3. 10. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (NORTH) ELEVATION. 819 (LEFT) 817 (RIGHT) - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  4. 7. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey Russell Jones, Photographer April 1959 ENTRANCE, 316 - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  5. 17. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Historic American Buildings Survey Russell Jones, Photographer April 1959 UNIT AT 132 - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  6. 8. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey Russell Jones, Photographer April 1959 DETAIL - 124 - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  7. 12. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Historic American Buildings Survey Russell Jones, Photographer April 1959 ENTRANCE DETAIL - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  8. 20. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (WEST) ELEVATION FROM THE N. W. - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  9. 2. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Russell Jones, Photographer April 1959 REAR (NORTH) ELEVATION FROM THE N. W. - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  10. 22. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (EAST) ELEVATION FROM THE S. E. - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  11. 11. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic American Buildings Survey Russell Jones, Photographer April 1959 GENERAL VIEW FROM THE EAST. 1016 and 1018. - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  12. 11. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (7th STREET) ELEVATION FRON THE SOUTH EAST - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  13. 1. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Russell Jones, Photographer April 1959 EAST END OF GROUP FROM THE NORTH - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  14. 5. Historic American Buildings Survey Russell Jones, Photographer March 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey Russell Jones, Photographer March 1959 DETAIL - PLAQUE - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  15. 15. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Historic American Buildings Survey Russell Jones, Photographer April 1959 REAR (EAST) AND LEFT (NORTH) ELEVATIONS - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  16. 9. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (SOUTH) ELEVATION FROM THE SOUTH EAST 706 (LEFT) 708 (RIGHT) - Southeast Area Survey, 330 & 706-708 Virginia Avenue (Houses), 306-308,324-326 Virginia Avenue (Houses), 156-158 North Carolina Avenue (Houses), Washington, District of Columbia, DC

  17. 13. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (EAST) ELEVATION. 1105 (LEFT) 1103 (RIGHT) - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  18. 4. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (WEST) ELEVATION - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  19. 10. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Historic American Buildings Survey Russell Jones, Photographer April 1959 GENERAL VIEW FROM THE SOUTH - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  20. 4. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey Russell Jones, Photographer April 1959 DETAIL - ONE UNIT OF GROUP - Southeast Area Survey, 101 & 122-124 Carroll Street (House), 1008 Potomac Street (House), Canal Street at Independence Avenue (Row House), 1016-1018 Potomac Street (House), Washington, District of Columbia, DC

  1. 18. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Historic American Buildings Survey Russell Jones, Photographer April 1959 ENTRANCE, 132 (LEFT) 134 (RIGHT) - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  2. 8. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey Russell Jones, Photographer April 1959 ENTRANCE, 318 - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  3. 6. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (WEST) ELEVATION (316 AT THE LEFT) - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  4. 16. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (WEST) ELEVATION (132 ON THE LEFT) - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  5. 3. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Russell Jones, Photographer April 1959 FRONT (EAST) ELEVATION - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  6. 10. Historic American Buildings Survey Russell Jones, Photographer April 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Historic American Buildings Survey Russell Jones, Photographer April 1959 REAR(EAST) & LEFT ELEVATIONS FROM THE N. E. - Southeast Area Survey, Sixth & G Streets (Synagogue), 132-144 & 900-905 Eleventh Street (Row Houses), 215 Second Street (House), Seventh & G Streets (School), 214 First Street (House), Washington, District of Columbia, DC

  7. Birefringence of Cellotape: Jones Representation and Experimental Analysis

    ERIC Educational Resources Information Center

    Belendez, Augusto; Fernandez, Elena; Frances, Jorge; Neipp, Cristian

    2010-01-01

    In this paper, we analyse a simple experiment to study the effects of polarized light. A simple optical system composed of a polarizer, a retarder (cellotape) and an analyser is used to study the effect on the polarization state of the light which impinges on the setup. The optical system is characterized by means of a Jones matrix, and a simple…

  8. A tribute to Robert Edwards and Howard Jones Jr

    PubMed Central

    Ombelet, W.

    2011-01-01

    “2010 was a fascinating year. Robert Edwards finally received the Nobel prize for Medicine and his friend in the United States, Howard W. Jones Jr. was honored in Denver by the American Society of Reproductive Medicine (ASRM) upon his Centennial Birthday. He turned 100 on December 30th” PMID:24753845

  9. DREDGED MATERIAL RECLAMATION AT THE JONES ISLAND CONFINED DISPOSAL FACILITY SITE CAPSULE

    EPA Science Inventory

    In this SITE demonstration, phytoremediation technology was applied to contaminated dredged materials from the Jones Island Confined Disposal Facility (CDF) located in Milwaukee Harbor, Wisconsin. The Jones Island CDF receives dredged materials from normal maintenance of Milwauke...

  10. DREDGED MATERIAL RECLAMATION AT THE JONES ISLAND CONFINED DISPOSAL FACILITY - ITER

    EPA Science Inventory

    In this SITE demonstration, phytoremediation technology was applied to contaminated dredged materials from the Jones Island Confined Disposal Facility (CDF) located in Milwaukee Harbor, Wisconsin. The Jones Island CDF receives dredged materials from normal maintenance of Milwauke...

  11. DREDGED MATERIAL RECLAMATION AT THE JONES ISLAND CONFINED DISPOSAL FACILITY - ITER

    EPA Science Inventory

    In this SITE demonstration, phytoremediation technology was applied to contaminated dredged materials from the Jones Island Confined Disposal Facility (CDF) located in Milwaukee Harbor, Wisconsin. The Jones Island CDF receives dredged materials from normal maintenance of Milwauke...

  12. DREDGED MATERIAL RECLAMATION AT THE JONES ISLAND CONFINED DISPOSAL FACILITY SITE CAPSULE

    EPA Science Inventory

    In this SITE demonstration, phytoremediation technology was applied to contaminated dredged materials from the Jones Island Confined Disposal Facility (CDF) located in Milwaukee Harbor, Wisconsin. The Jones Island CDF receives dredged materials from normal maintenance of Milwauke...

  13. 75 FR 20802 - Safety Zone; New York Air Show at Jones Beach State Park, Atlantic Ocean off of Jones Beach...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ... Interference with Constitutionally Protected Property Rights. Civil Justice Reform This proposed rule meets... State Park during the week before Memorial Day. Jones Beach State Park is located on the south shore of... shows generally take place from 10 a.m. to 3 p.m. every day from Thursday through Sunday before Memorial...

  14. 21 CFR 866.5150 - Bence-Jones proteins immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the Bence-Jones proteins in urine and plasma. Immunoglobulin molecules normally consist of pairs of... disulfide bridges. In some cancerous conditions, there is a proliferation of one plasma cell (antibody... plasma, and have been called Bence-Jones proteins. Measurement of Bence-Jones proteins and determination...

  15. 21 CFR 866.5150 - Bence-Jones proteins immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the Bence-Jones proteins in urine and plasma. Immunoglobulin molecules normally consist of pairs of... disulfide bridges. In some cancerous conditions, there is a proliferation of one plasma cell (antibody... plasma, and have been called Bence-Jones proteins. Measurement of Bence-Jones proteins and determination...

  16. 21 CFR 866.5150 - Bence-Jones proteins immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the Bence-Jones proteins in urine and plasma. Immunoglobulin molecules normally consist of pairs of... disulfide bridges. In some cancerous conditions, there is a proliferation of one plasma cell (antibody... plasma, and have been called Bence-Jones proteins. Measurement of Bence-Jones proteins and determination...

  17. 21 CFR 866.5150 - Bence-Jones proteins immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the Bence-Jones proteins in urine and plasma. Immunoglobulin molecules normally consist of pairs of... disulfide bridges. In some cancerous conditions, there is a proliferation of one plasma cell (antibody... plasma, and have been called Bence-Jones proteins. Measurement of Bence-Jones proteins and determination...

  18. 21 CFR 866.5150 - Bence-Jones proteins immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the Bence-Jones proteins in urine and plasma. Immunoglobulin molecules normally consist of pairs of... disulfide bridges. In some cancerous conditions, there is a proliferation of one plasma cell (antibody... plasma, and have been called Bence-Jones proteins. Measurement of Bence-Jones proteins and determination...

  19. Gauge-origin independent calculations of Jones birefringence

    NASA Astrophysics Data System (ADS)

    Shcherbin, Dmitry; Thorvaldsen, Andreas J.; Jonsson, Dan; Ruud, Kenneth

    2011-10-01

    We present the first gauge-origin independent formulation of Jones birefringence at the Hartree-Fock level of theory. Gauge-origin independence is achieved through the use of London atomic orbitals. The implementation is based on a recently proposed atomic orbital-based response theory formulation that allows for the use of both time- and perturbation-dependent basis sets [Thorvaldsen, Ruud, Kristensen, Jørgensen, and Coriani, J. Chem. Phys. 129, 214108 (2008)]. We present the detailed expressions for the response functions entering the Jones birefringence when London atomic orbitals are used. The implementation is tested on a set of polar and dipolar molecules at the Hartree-Fock level of theory. It is demonstrated that London orbitals lead to much improved basis-set convergence, and that the use of small, conventional basis sets may lead to the wrong sign for the calculated birefringence. For large basis sets, London orbitals and conventional basis sets converge to the same results.

  20. Second virial coefficient of a generalized Lennard-Jones potential.

    PubMed

    González-Calderón, Alfredo; Rocha-Ichante, Adrián

    2015-01-21

    We present an exact analytical solution for the second virial coefficient of a generalized Lennard-Jones type of pair potential model. The potential can be reduced to the Lennard-Jones, hard-sphere, and sticky hard-sphere models by tuning the potential parameters corresponding to the width and depth of the well. Thus, the second virial solution can also regain the aforementioned cases. Moreover, the obtained expression strongly resembles the one corresponding to the Kihara potential. In fact, the Fk functions are the same. Furthermore, for these functions, the complete expansions at low and high temperature are given. Additionally, we propose an alternative stickiness parameter based on the obtained second virial coefficient.

  1. Second virial coefficient of a generalized Lennard-Jones potential

    NASA Astrophysics Data System (ADS)

    González-Calderón, Alfredo; Rocha-Ichante, Adrián

    2015-01-01

    We present an exact analytical solution for the second virial coefficient of a generalized Lennard-Jones type of pair potential model. The potential can be reduced to the Lennard-Jones, hard-sphere, and sticky hard-sphere models by tuning the potential parameters corresponding to the width and depth of the well. Thus, the second virial solution can also regain the aforementioned cases. Moreover, the obtained expression strongly resembles the one corresponding to the Kihara potential. In fact, the Fk functions are the same. Furthermore, for these functions, the complete expansions at low and high temperature are given. Additionally, we propose an alternative stickiness parameter based on the obtained second virial coefficient.

  2. 'Jones hybrid' hickory: a case study in Carya curation.

    PubMed

    Grauke, L J; Mendoza-Herrera, M Azucena; Stelly, David M; Klein, Patricia E

    2016-01-01

    'Jones Hybrid' hickory is an accession in the National Collection of Genetic Resources for Pecans and Hickories for which information about origin, identity and characteristics is very incomplete. Phenotypic and genetic profiles, when examined in the context of historic literature, provide evidence that the accession in question is 'Siers' a cultivar of Carya × laneyi (an interspecific hybrid between C. ovata and C. cordiformis). The accession has traits that make it interesting in the pecan breeding program, with potential for both rootstock and scion development. The tall, slender tree form of 'Jones Hybrid' is a trait that could be valuable in commercial pecan cultivars, allowing increased tree densities and reducing the need for expensive hedging operations. Tree size reduction is a goal to be pursued in scion selection and rootstock development, with each goal requiring assessment of reproductive potential of the accession.

  3. Jones matrix treatment for optical Fourier processors with structured polarization.

    PubMed

    Moreno, Ignacio; Iemmi, Claudio; Campos, Juan; Yzuel, Maria J

    2011-02-28

    We present a Jones matrix method useful to analyze coherent optical Fourier processors employing structured polarization. The proposed method is a generalization of the standard classical optical Fourier transform processor, but considering vectorial spatial functions with two complex components corresponding to two orthogonal linear polarizations. As a result we derive a Jones matrix that describes the polarization output in terms of two vectorial functions defining respectively the structured polarization input and the generalized polarization impulse response. We apply the method to show and analyze an experiment in which a regular scalar diffraction grating is converted into equivalent polarization diffraction gratings by means of an appropriate polarization filtering. The technique is further demonstrated to generate arbitrary structured polarizations. Excellent experimental results are presented.

  4. Gas-solid coexistence of the Lennard-Jones system

    NASA Astrophysics Data System (ADS)

    van der Hoef, Martin A.

    2002-09-01

    Recently, the absolute free energies of the Lennard-Jones system at solid-liquid and solid-gas coexistence were computed from Monte Carlo simulations [J. Chem. Phys. 116, 7145 (2002)]. In this note, we show that the values along the sublimation line are in good agreement with the results from an equation of state published earlier [J. Chem. Phys. 113, 8142 (2000)]. The present values for the thermodynamic properties along the sublimation line are the most accurate reported to date.

  5. Mueller-Jones Matrix measurement in material identification

    NASA Astrophysics Data System (ADS)

    Xu, Jiang; Qian, Weixian; Wang, Xiao

    2016-09-01

    The uniformity of lattice arrangement plays an important role in industrial processing, science and technology studies and environmental pollution detection. However, there are very little papers to study surface structure by depolarization characteristics. In order to improve the efficiency and accuracy of material identification system by polarization technology, we developed a new method to decompose the Mueller matrix, we studied the mechanism of the scattering of electromagnetic wave, and analyzed the relationship between the characteristics of depolarization and mechanism of scattering. We used the Jones Matrix and Mueller Matrix to set up the physical model, and decomposed the Mueller-Jones Matrix by the characteristics of polarization, then got the depolarization coefficients (ωd) of the surfaces of the samples. By using this theory, we deduced the relation formula of Mueller matrix, Mueller-Jones matrix and Isotropic-Depolarizer matrix. Based on the polarized characteristics of the samples, we analyzed design method of material identification system and gave the results of the experimental test. Finally, we applied the theory of Fresnel formulas to verify the theoretical model. From the results, we found that the depolarization coefficients of the samples' surfaces were related to the scattering, and in the whole measurement process, the depolarization coefficients of the samples were far different; the method could easily to distinguish the metal and nonmetal, and more quickly to analyze the surface roughness of the samples. Therefore, the depolarization technology had a great application value, and the paper had very important significance on the development of surface structure study.

  6. Partitioned density functional approach for a Lennard-Jones fluid.

    PubMed

    Zhou, Shiqi

    2003-12-01

    The existing classical density functional approach for nonuniform Lennard-Jones fluid, which is based on dividing the Lennard-Jones interaction potential into a short-range, repulsive part, and a smoothly varying, long-range, attractive tail, was improved by dividing the bulk second-order direct correlation function into strongly density-depending short-range part and weakly density-depending long-range part. The latter is treated by functional perturbation expansion truncated at the lowest order whose accuracy depends on how weakly the long-range part depends on the bulk density. The former is treated by the truncated functional perturbation expansion which is rewritten in the form of the simple weighted density approximation and incorporates the omitted higher-order terms by applying Lagrangian theorem of differential calculus to the reformulated form. The two approximations are put into the density profile equation of the density functional theory formalism to predict the density distribution for Lennard-Jones fluid in contact with a hard wall or between two hard walls within the whole density range for reduced temperature T(*)=1.35 and a density point for reduced temperature T(*)=1. The present partitioned density functional theory performs much better than several previous density functional perturbation theory approaches and a recently proposed bridge density functional approximation.

  7. Quantum algorithms for virtual Jones polynomials via Thistlethwaite theorems

    NASA Astrophysics Data System (ADS)

    Vélez, Mario; Ospina, Juan

    2010-04-01

    Recently a quantum algorithm for the Jones polynomial of virtual links was proposed by Kauffman and Dye via the implementation of the virtual braid group in anyonic topological quantum computation when the virtual crossings are considered as generalized swap gates. Also recently, a mathematical method for the computation of the Jones polynomial of a given virtual link in terms of the relative Tuttle polynomial of its face (Tait) graph with some suitable variable substitutions was proposed by Diao and Hetyei. The method of Diao and Hetyei is offered as an alternative to the ribbon graph approach according to which the Tutte polynomial of a given virtual link is computed in terms of the Bollobás- Riordan polynomial of the corresponding ribbon graph. The method of Diao and Hetyei can be considered as an extension of the celebrated Thistlethwaite theorem according to which invariant polynomials for knots and links are derived from invariant polynomials for graphs. Starting from these ideas we propose a quantum algorithm for the Jones polynomial of a given virtual link in terms of the generalized Tutte polynomials by exploiting the Thistlethwaite theorem and the Kauffman algorithm . Our method is claimed as the quantum version of the Diao-Hetyei method. Possible supersymmetric implementations of our algortihm are discussed jointly with its formulations using topological quantum lambda calculus.

  8. A Viola-Jones based hybrid face detection framework

    NASA Astrophysics Data System (ADS)

    Murphy, Thomas M.; Broussard, Randy; Schultz, Robert; Rakvic, Ryan; Ngo, Hau

    2013-12-01

    Improvements in face detection performance would benefit many applications. The OpenCV library implements a standard solution, the Viola-Jones detector, with a statistically boosted rejection cascade of binary classifiers. Empirical evidence has shown that Viola-Jones underdetects in some instances. This research shows that a truncated cascade augmented by a neural network could recover these undetected faces. A hybrid framework is constructed, with a truncated Viola-Jones cascade followed by an artificial neural network, used to refine the face decision. Optimally, a truncation stage that captured all faces and allowed the neural network to remove the false alarms is selected. A feedforward backpropagation network with one hidden layer is trained to discriminate faces based upon the thresholding (detection) values of intermediate stages of the full rejection cascade. A clustering algorithm is used as a precursor to the neural network, to group significant overlappings. Evaluated on the CMU/VASC Image Database, comparison with an unmodified OpenCV approach shows: (1) a 37% increase in detection rates if constrained by the requirement of no increase in false alarms, (2) a 48% increase in detection rates if some additional false alarms are tolerated, and (3) an 82% reduction in false alarms with no reduction in detection rates. These results demonstrate improved face detection and could address the need for such improvement in various applications.

  9. Communication: Low-temperature approximation of the virial series for the Lennard-Jones and modified Lennard-Jones models.

    PubMed

    Ushcats, M V

    2014-09-14

    The regularity of the existing data on the virial coefficients for the Lennard-Jones and modified Lennard-Jones models has allowed a rough extrapolation to the coefficients of higher orders. The corresponding approximation of the infinite virial series has been proposed for the limited temperature interval: 0.4-0.8 of the critical temperature. The loci of zero points of isothermal bulk modulus obtained on the basis of this approximation are close to the vapor-liquid branch of the experimental binodal rather than spinodal. In addition, those points ((dP/dV)T = 0) almost coincide with the divergence points of the approximated virial series that may eliminate some disputable questions about the boundaries of adequacy for the virial equation of state and makes the theoretical isotherms qualitatively similar to the real in the condensation region.

  10. Accurate Critical Parameters for the Modified Lennard-Jones Model

    NASA Astrophysics Data System (ADS)

    Okamoto, Kazuma; Fuchizaki, Kazuhiro

    2017-03-01

    The critical parameters of the modified Lennard-Jones system were examined. The isothermal-isochoric ensemble was generated by conducting a molecular dynamics simulation for the system consisting of 6912, 8788, 10976, and 13500 particles. The equilibrium between the liquid and vapor phases was judged from the chemical potential of both phases upon establishing the coexistence envelope, from which the critical temperature and density were obtained invoking the renormalization group theory. The finite-size scaling enabled us to finally determine the critical temperature, pressure, and density as Tc = 1.0762(2), pc = 0.09394(17), and ρc = 0.331(3), respectively.

  11. [Thermodynamic and hydrodynamic study of Bence-Jones proteins].

    PubMed

    Tishchenko, V M; Khristoforov, V S; Blizniukov, O P

    2009-01-01

    Four Bence-Jones proteins were investigated by CD, fluorescence and analytical ultracentrifugation methods at physiological conditions (10 mM phosphate buffer, pH 7.0, 100 mM NaCl). A joint analysis of optical melting curves for proteins and their fragments were demonstrated that protein VAD has reduced stability of its constant half, which correlates with the ability of both intact protein and its constant, rather than variable part to form amyloid fibrils. Data are reported which support the viewpoint that the detected decrease in the stability is caused by abnormal interaction between a pair of constant domains C(L).

  12. Enhanced Crystal Growth in Binary Lennard-Jones Mixtures

    NASA Astrophysics Data System (ADS)

    Radu, M.; Kremer, K.

    2017-02-01

    We study the crystal growth in binary Lennard-Jones mixtures by molecular dynamics simulations. Growth dynamics, the structure of the liquid-solid interfaces as well as droplet incorporation into the crystal vary with solution properties. For demixed systems we observe a strongly enhanced crystal growth at the cost of enclosed impurities. Furthermore, we find different interface morphologies depending on solubility. We relate our observations to growth mechanisms based on the Gibbs-Thomson effect as well as to predictions of the Kardar-Parisi-Zhang theory in 2 +1 dimensions.

  13. Transpose symmetry of the Jones matrix and topological phases.

    PubMed

    Bhandari, Rajendra

    2008-04-15

    The transmission Jones matrix of an arbitrary stack of reciprocal plane-parallel plates that has been turned through 180 degrees about an axis in the plane of the stack is, in an appropriate basis, the transpose of the transmission matrix of the unturned slab with a change in the sign of the off-diagonal elements. We prove this convention-free result for the case where reflection at the interfaces can be ignored and use it to devise an experimental scheme to separate isotropic and topological phase changes in a reciprocal optical medium.

  14. Lennard-Jones and lattice models of driven fluids.

    PubMed

    Díez-Minguito, M; Garrido, P L; Marro, J

    2005-08-01

    We introduce a nonequilibrium off-lattice model for anisotropic phenomena in fluids. This is a Lennard-Jones generalization of the driven lattice-gas model in which the particles' spatial coordinates vary continuously. A comparison between the two models allows us to discuss some exceptional, hardly realistic features of the original discrete system--which has been considered a prototype for nonequilibrium anisotropic phase transitions. We thus help to clarify open issues, and discuss on the implications of our observations for future investigation of anisotropic phase transitions.

  15. Structure diagram of binary Lennard-Jones clusters

    NASA Astrophysics Data System (ADS)

    Mravlak, Marko; Kister, Thomas; Kraus, Tobias; Schilling, Tanja

    2016-07-01

    We analyze the structure diagram for binary clusters of Lennard-Jones particles by means of a global optimization approach for a large range of cluster sizes, compositions, and interaction energies and present a publicly accessible database of 180 000 minimal energy structures (http://softmattertheory.lu/clusters.html). We identify a variety of structures such as core-shell clusters, Janus clusters, and clusters in which the minority species is located at the vertices of icosahedra. Such clusters can be synthesized from nanoparticles in agglomeration experiments and used as building blocks in colloidal molecules or crystals. We discuss the factors that determine the formation of clusters with specific structures.

  16. Structure diagram of binary Lennard-Jones clusters.

    PubMed

    Mravlak, Marko; Kister, Thomas; Kraus, Tobias; Schilling, Tanja

    2016-07-14

    We analyze the structure diagram for binary clusters of Lennard-Jones particles by means of a global optimization approach for a large range of cluster sizes, compositions, and interaction energies and present a publicly accessible database of 180 000 minimal energy structures (http://softmattertheory.lu/clusters.html). We identify a variety of structures such as core-shell clusters, Janus clusters, and clusters in which the minority species is located at the vertices of icosahedra. Such clusters can be synthesized from nanoparticles in agglomeration experiments and used as building blocks in colloidal molecules or crystals. We discuss the factors that determine the formation of clusters with specific structures.

  17. Bubble nucleation in a Lennard-Jones binary liquid mixture

    NASA Astrophysics Data System (ADS)

    Baidakov, Vladimir G.; Protsenko, Sergey P.; Bryukhanov, Vasiliy M.

    2016-10-01

    We report a molecular dynamics (MD) study of homogeneous bubble nucleation in a stretched Lennard-Jones binary mixture at a temperature close to the solvent triple point. The pressure of the limiting stretching pn corresponding to a fixed value of the nucleation rate has been determined. The values of pn achieved in MD simulation are lower than those calculated from classical nucleation theory (CNT). The discrepancy between the data of MD simulation and CNT may be connected with the neglect in the latter of the size dependence of the surface tension of critical bubbles.

  18. Enhanced Crystal Growth in Binary Lennard-Jones Mixtures.

    PubMed

    Radu, M; Kremer, K

    2017-02-03

    We study the crystal growth in binary Lennard-Jones mixtures by molecular dynamics simulations. Growth dynamics, the structure of the liquid-solid interfaces as well as droplet incorporation into the crystal vary with solution properties. For demixed systems we observe a strongly enhanced crystal growth at the cost of enclosed impurities. Furthermore, we find different interface morphologies depending on solubility. We relate our observations to growth mechanisms based on the Gibbs-Thomson effect as well as to predictions of the Kardar-Parisi-Zhang theory in 2+1 dimensions.

  19. Origin of line tension for a Lennard-Jones nanodroplet

    NASA Astrophysics Data System (ADS)

    Weijs, Joost H.; Marchand, Antonin; Andreotti, Bruno; Lohse, Detlef; Snoeijer, Jacco H.

    2011-02-01

    The existence and origin of line tension has remained controversial in literature. To address this issue, we compute the shape of Lennard-Jones nanodrops using molecular dynamics and compare them to density functional theory in the approximation of the sharp kink interface. We show that the deviation from Young's law is very small and would correspond to a typical line tension length scale (defined as line tension divided by surface tension) similar to the molecular size and decreasing with Young's angle. We propose an alternative interpretation based on the geometry of the interface at the molecular scale.

  20. Advanced Jones calculus for the classification of periodic metamaterials

    NASA Astrophysics Data System (ADS)

    Menzel, Christoph; Rockstuhl, Carsten; Lederer, Falk

    2010-11-01

    By relying on an advanced Jones calculus, we analyze the polarization properties of light upon propagation through metamaterial slabs in a comprehensive manner. Based on symmetry considerations, we show that all periodic metamaterials may be divided into five different classes only. It is shown that each class differently affects the polarization of the transmitted light and sustains different eigenmodes. We show how to deduce these five classes from symmetry considerations and provide a simple algorithm that can be applied to decide to which class a given metamaterial belongs by measuring only the transmitted intensities.

  1. The genus Unixenus Jones, 1944 (Diplopoda, Penicillata, Polyxenida) in Australia

    PubMed Central

    Short, Megan; Huynh, Cuong

    2011-01-01

    Abstract The penicillate genus Unixenus Jones, 1944 is widespread, with species found in Africa, Madagascar, India and Australia. Each of the two Australian species was originally described from single samples from Western Australia. In this study, collections of Penicillata from museums in all states of Australia were examined to provide further details of the two described species, to revise the diagnoses for both the genus and the species, and to better understand the distribution of the two species in Australia. In addition, two new species Unixenus karajinensis sp. n. and Unixenus corticolus sp. n. are described. PMID:22303098

  2. Advanced Jones calculus for the classification of periodic metamaterials

    SciTech Connect

    Menzel, Christoph; Rockstuhl, Carsten; Lederer, Falk

    2010-11-15

    By relying on an advanced Jones calculus, we analyze the polarization properties of light upon propagation through metamaterial slabs in a comprehensive manner. Based on symmetry considerations, we show that all periodic metamaterials may be divided into five different classes only. It is shown that each class differently affects the polarization of the transmitted light and sustains different eigenmodes. We show how to deduce these five classes from symmetry considerations and provide a simple algorithm that can be applied to decide to which class a given metamaterial belongs by measuring only the transmitted intensities.

  3. 3. Historic American Buildings Survey Russell Jones, Photographer June 1963NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Russell Jones, Photographer June 1963NORTHWEST VIEW - Abner Cloud House, Intersection of Canal Road & Reservoir Road Northwest, Washington, District of Columbia, DC

  4. Phase diagram of the modified Lennard-Jones system.

    PubMed

    Asano, Yuta; Fuchizaki, Kazuhiro

    2012-11-07

    An investigation of the precise determination of melting temperature in the modified Lennard-Jones system under pressure-free conditions [Y. Asano and K. Fuchizaki, J. Phys. Soc. Jpn. 78, 055002 (2009)] was extended under finite-pressure conditions to obtain the phase diagram. The temperature and pressure of the triple point were estimated to be 0.61 ε∕k(B) and 0.0018(5) ε∕σ(3), and those of the critical point were 1.0709(19) ε∕k(B) and 0.1228(20) ε∕σ(3), where ε and σ are the Lennard-Jones parameters for energy and length scales, respectively, and k(B) is the Boltzmann constant. The potential used here has a finite attractive tail and does not suffer from cutoff problems. The potential can thus be a useful standard in examining statistical-mechanical problems in which different treatments for the tail would lead to different conclusions. The present phase diagram will then be a useful guide not only for equilibrium calculations but also for nonequilibrium problems such as discussions of the limits of phase (in)stability.

  5. The BQP-hardness of approximating the Jones polynomial

    NASA Astrophysics Data System (ADS)

    Aharonov, Dorit; Arad, Itai

    2011-03-01

    A celebrated important result due to Freedman et al (2002 Commun. Math. Phys. 227 605-22) states that providing additive approximations of the Jones polynomial at the kth root of unity, for constant k=5 and k>=7, is BQP-hard. Together with the algorithmic results of Aharonov et al (2005) and Freedman et al (2002 Commun. Math. Phys. 227 587-603), this gives perhaps the most natural BQP-complete problem known today and motivates further study of the topic. In this paper, we focus on the universality proof; we extend the result of Freedman et al (2002) to ks that grow polynomially with the number of strands and crossings in the link, thus extending the BQP-hardness of Jones polynomial approximations to all values to which the AJL algorithm applies (Aharonov et al 2005), proving that for all those values, the problems are BQP-complete. As a side benefit, we derive a fairly elementary proof of the Freedman et al density result, without referring to advanced results from Lie algebra representation theory, making this important result accessible to a wider audience in the computer science research community. We make use of two general lemmas we prove, the bridge lemma and the decoupling lemma, which provide tools for establishing the density of subgroups in SU(n). Those tools seem to be of independent interest in more general contexts of proving the quantum universality. Our result also implies a completely classical statement, that the multiplicative approximations of the Jones polynomial, at exactly the same values, are #P-hard, via a recent result due to Kuperberg (2009 arXiv:0908.0512). Since the first publication of those results in their preliminary form (Aharonov and Arad 2006 arXiv:quant-ph/0605181), the methods we present here have been used in several other contexts (Aharonov and Arad 2007 arXiv:quant-ph/0702008; Peter and Stephen 2008 Quantum Inf. Comput. 8 681). The present paper is an improved and extended version of the results presented by Aharonov and Arad

  6. The Double Jones Birefringence in Magneto-electric Medium

    PubMed Central

    Mahmood, Waqas; Zhao, Qing

    2015-01-01

    In this paper, the Maxwell’s equations for a tensorial magneto-electric (ME) medium are solved, which is an extension to the work on the uniaxial anisotropic nonmagnetic medium. The coefficients of the dielectric permittivity, magnetic permeability, and of the magneto-electric effect are considered as tensors. The polarization is shown lying in the plane of two perpendicular independent vectors, and the relationship for the transverse polarization is given. The propagation of an electromagnetic wave through a ME medium gives rise to double Jones birefringence. Besides, the condition for an independent phenomenon of D’yakonov surface wave in a magneto-isotropic but with magneto-electric medium is given, which is measurable experimentally when the incident angle is . Lastly, it is shown that the parameter for the magneto-electric effect plays a role in the damping of the wave. PMID:26354609

  7. Freezing point depression in model Lennard-Jones solutions

    NASA Astrophysics Data System (ADS)

    Koschke, Konstantin; Jörg Limbach, Hans; Kremer, Kurt; Donadio, Davide

    2015-09-01

    Crystallisation of liquid solutions is of uttermost importance in a wide variety of processes in materials, atmospheric and food science. Depending on the type and concentration of solutes the freezing point shifts, thus allowing control on the thermodynamics of complex fluids. Here we investigate the basic principles of solute-induced freezing point depression by computing the melting temperature of a Lennard-Jones fluid with low concentrations of solutes, by means of equilibrium molecular dynamics simulations. The effect of solvophilic and weakly solvophobic solutes at low concentrations is analysed, scanning systematically the size and the concentration. We identify the range of parameters that produce deviations from the linear dependence of the freezing point on the molal concentration of solutes, expected for ideal solutions. Our simulations allow us also to link the shifts in coexistence temperature to the microscopic structure of the solutions.

  8. Density effects in a bulk binary Lennard-Jones system

    NASA Astrophysics Data System (ADS)

    Hernández-Rojas, Javier; Wales, David J.

    2003-10-01

    Properties of local minima as a function of density are studied in a binary Lennard-Jones system for temperatures T=1.0 (normal liquid), 0.5 (supercooled liquid), and 0.4 (glass), in reduced units. The number of different local minima sampled, energy, pressure, normal mode angular frequencies, and partial radial distribution functions are presented for simulation times of constant length. In agreement with previous studies by Sastry [Phys. Rev. Lett. 85, 590 (2000)] a limiting density is found at ρl=1.08 with negative pressure, below which the local structure of the glass and the supercooled phases are essentially the same, as evidenced by the partial radial distribution functions.

  9. Phase behavior of the 38-atom Lennard-Jones cluster

    SciTech Connect

    Sehgal, Ray M.; Maroudas, Dimitrios E-mail: ford@ecs.umass.edu; Ford, David M. E-mail: ford@ecs.umass.edu

    2014-03-14

    We have developed a coarse-grained description of the phase behavior of the isolated 38-atom Lennard-Jones cluster (LJ{sub 38}). The model captures both the solid-solid polymorphic transitions at low temperatures and the complex cluster breakup and melting transitions at higher temperatures. For this coarse model development, we employ the manifold learning technique of diffusion mapping. The outcome of the diffusion mapping analysis over a broad temperature range indicates that two order parameters are sufficient to describe the cluster's phase behavior; we have chosen two such appropriate order parameters that are metrics of condensation and overall crystallinity. In this well-justified coarse-variable space, we calculate the cluster's free energy landscape (FEL) as a function of temperature, employing Monte Carlo umbrella sampling. These FELs are used to quantify the phase behavior and onsets of phase transitions of the LJ{sub 38} cluster.

  10. Corresponding states law for a generalized Lennard-Jones potential.

    PubMed

    Orea, P; Romero-Martínez, A; Basurto, E; Vargas, C A; Odriozola, G

    2015-07-14

    It was recently shown that vapor-liquid coexistence densities derived from Mie and Yukawa models collapse to define a single master curve when represented against the difference between the reduced second virial coefficient at the corresponding temperature and that at the critical point. In this work, we further test this proposal for another generalization of the Lennard-Jones pair potential. This is carried out for vapor-liquid coexistence densities, surface tension, and vapor pressure, along a temperature window set below the critical point. For this purpose, we perform molecular dynamics simulations by varying the potential softness parameter to produce from very short to intermediate attractive ranges. We observed all properties to collapse and yield master curves. Moreover, the vapor-liquid curve is found to share the exact shape of the Mie and attractive Yukawa. Furthermore, the surface tension and the logarithm of the vapor pressure are linear functions of this difference of reduced second virial coefficients.

  11. MS Jones in U.S. Laboratory / Destiny module

    NASA Image and Video Library

    2001-02-11

    STS98-E-5137 (11 February 2001) --- Astronauts Thomas D. Jones (foreground), STS-98 mission specialist, and William M. Shepherd, Expedition One mission commander, participate in an impromptu photo shoot onboard the newly opened Destiny laboratory on the International Space Station (ISS). After Shepherd opened the Destiny hatch, he and astronaut Kenneth D. Cockrell (out of frame) ventured inside at 8:38 a.m. (CST), February 11, 2001. As depicted in subsequent digital images in this series, members of both crews went to work quickly inside the new module, activating air systems, fire extinguishers, alarm systems, computers and internal communications. The crew also took some photos and continued equipment transfers from the shuttle to the station.

  12. Molecular dynamics simulations of crystallization of Lennard-Jones nanoparticles

    NASA Astrophysics Data System (ADS)

    Thi Thuy Huong, Ta; Van Hoang, Vo; Khuong Cat, Phan Ngoc

    2014-07-01

    Crystallization of Lennard-Jones nanoparticles has been studied by molecular dynamics (MD) simulations. Spherical models with free surface are cooled from the melt to crystalline state. In the cooling process, thermodynamics, structural properties and atomic mechanism of the crystallization are investigated. We found that crystallization in nanoparticles follows the Ostwald's step rule like that found in the past. Due to free surface contribution, the solidification exhibits non-homogeneous behavior which proceeds in different manners between core and surface: homogeneous crystallization in the core and heterogeneous one in the surface layer of nanoparticles. It is due to the discrepancy between structures of two parts: highly ordered structure dominates in the core region while the surface exhibits defective one with a high fraction of undercoordinated sites. Also, our results are consistent with previous ones about the free surface-induced phenomena.

  13. Vectorial polarization modes platform realized with Jones vectors in mathematica

    NASA Astrophysics Data System (ADS)

    Choi, Yong-Dae; Yun, Hee-Joong

    2015-09-01

    The fundamental concept in physics of polarization propagation of electromagnetic waves is newly understood to be a cardinal keyword in quantum cryptography transport technology and the Standard Model. Interactive visualization of the propagation mechanism of polarized electromagnetism in a medium with its helicity has received attention recently from scientists in the age of information and communication. This study presents a new dynamic polarization platform that presents the polarization modes of a transverse electromagnetic wave by using Jones vectors calculations in the symbolic program Mathematica to convert the state of polarization through the arrangement of the optical elements. The platform simulates a propagation process that satisfies Maxwell's two vector equations precisely with the vectorial nature of the electromagnetic wave.

  14. The Double Jones Birefringence in Magneto-electric Medium

    NASA Astrophysics Data System (ADS)

    Mahmood, Waqas; Zhao, Qing

    2015-09-01

    In this paper, the Maxwell’s equations for a tensorial magneto-electric (ME) medium are solved, which is an extension to the work on the uniaxial anisotropic nonmagnetic medium. The coefficients of the dielectric permittivity, magnetic permeability, and of the magneto-electric effect are considered as tensors. The polarization is shown lying in the plane of two perpendicular independent vectors, and the relationship for the transverse polarization is given. The propagation of an electromagnetic wave through a ME medium gives rise to double Jones birefringence. Besides, the condition for an independent phenomenon of D’yakonov surface wave in a magneto-isotropic but with magneto-electric medium is given, which is measurable experimentally when the incident angle is . Lastly, it is shown that the parameter for the magneto-electric effect plays a role in the damping of the wave.

  15. The Lennard-Jones melting line and isomorphism.

    PubMed

    Heyes, D M; Brańka, A C

    2015-12-21

    The location of the melting line (ML) of the Lennard-Jones (LJ) system and its associated physical properties are investigated using molecular dynamics computer simulation. The radial distribution function and the behavior of the repulsive and attractive parts of the potential energy indicate that the ML is not a single isomorph, but the isomorphic state evolves gradually with temperature, i.e., it is only "locally isomorphic." The state point dependence of the unitless isomorphic number, X̃, for a range of static and dynamical properties of the LJ system in the solid and fluid states, and for fluid argon, are also reported. The quantity X̃ typically varies most with state point in the vicinity of the triple point and approaches a plateau in the high density (temperature) limit along the ML.

  16. Metastable Lennard-Jones fluids. III. Bulk viscosity.

    PubMed

    Baidakov, Vladimir G; Protsenko, Sergey P

    2014-09-21

    The method of equilibrium molecular-dynamics simulation in combination with the Green-Kubo formula has been used to calculate the bulk viscosity of a Lennard-Jones fluid. Calculations have been made at temperatures 0.4 ≤ k(B)T/ɛ ≤ 2.0 and densities 0.0075 ≤ ρσ(3) ≤ 1.2 at 116 stable and 106 metastable states of liquid and gas. The depth of penetration into the region of metastable states was limited by spontaneous nucleation. In the region of stable states the data obtained are compared with the results of previous investigations. It has been established that the system transition across the lines of liquid-gas and liquid-crystal phase equilibrium and penetration into the metastable regions of liquid and gas are connected with increasing bulk viscosity. The behavior of bulk viscosity close to the spinodal of a superheated liquid and supersaturated vapor is discussed.

  17. Phase behavior of the 38-atom Lennard-Jones cluster.

    PubMed

    Sehgal, Ray M; Maroudas, Dimitrios; Ford, David M

    2014-03-14

    We have developed a coarse-grained description of the phase behavior of the isolated 38-atom Lennard-Jones cluster (LJ38). The model captures both the solid-solid polymorphic transitions at low temperatures and the complex cluster breakup and melting transitions at higher temperatures. For this coarse model development, we employ the manifold learning technique of diffusion mapping. The outcome of the diffusion mapping analysis over a broad temperature range indicates that two order parameters are sufficient to describe the cluster's phase behavior; we have chosen two such appropriate order parameters that are metrics of condensation and overall crystallinity. In this well-justified coarse-variable space, we calculate the cluster's free energy landscape (FEL) as a function of temperature, employing Monte Carlo umbrella sampling. These FELs are used to quantify the phase behavior and onsets of phase transitions of the LJ38 cluster.

  18. Corresponding states law for a generalized Lennard-Jones potential

    NASA Astrophysics Data System (ADS)

    Orea, P.; Romero-Martínez, A.; Basurto, E.; Vargas, C. A.; Odriozola, G.

    2015-07-01

    It was recently shown that vapor-liquid coexistence densities derived from Mie and Yukawa models collapse to define a single master curve when represented against the difference between the reduced second virial coefficient at the corresponding temperature and that at the critical point. In this work, we further test this proposal for another generalization of the Lennard-Jones pair potential. This is carried out for vapor-liquid coexistence densities, surface tension, and vapor pressure, along a temperature window set below the critical point. For this purpose, we perform molecular dynamics simulations by varying the potential softness parameter to produce from very short to intermediate attractive ranges. We observed all properties to collapse and yield master curves. Moreover, the vapor-liquid curve is found to share the exact shape of the Mie and attractive Yukawa. Furthermore, the surface tension and the logarithm of the vapor pressure are linear functions of this difference of reduced second virial coefficients.

  19. Dow Jones Fund Opens Journalism Programs to White Students after Lawsuit

    ERIC Educational Resources Information Center

    Scmidt, Peter

    2007-01-01

    This paper discusses a Lawsuit filed against Dow Jones Newspaper Fund and the legal settlement between the defendant and the plaintiff. The fund, a nonprofit organization affiliated with Dow Jones & Company had been operating more than 20 programs for minority high-school students to pursue careers in newspaper journalism. The organization…

  20. Stereotype Threat Paradigm in Search of a Phenomenon: A Comment on Kellow and Jones's (2008) Study

    ERIC Educational Resources Information Center

    Whaley, Arthur L.

    2009-01-01

    In a recent study, Kellow and Jones apply the stereotype threat paradigm to a sample of African American students attending an urban high school. The purpose of this commentary is to provide a conceptual and methodological critique of Kellow and Jones's study. Implications for the role of Black psychologists in evaluating research on African…

  1. Essential Characteristics of an Highly Resilient Judge: A Case Study of the Honorable Richard Jones

    ERIC Educational Resources Information Center

    Ericksen, Charles Aaron

    2010-01-01

    The purpose of this study was to explore judicial resiliency through the personal experiences and perspectives of an experienced trial court judge, the Honorable Richard Jones. This exploratory case study examined the coping skills, traits, and attributes exhibited by Judge Jones over his career and in particular through the experience of…

  2. Dow Jones Fund Opens Journalism Programs to White Students after Lawsuit

    ERIC Educational Resources Information Center

    Scmidt, Peter

    2007-01-01

    This paper discusses a Lawsuit filed against Dow Jones Newspaper Fund and the legal settlement between the defendant and the plaintiff. The fund, a nonprofit organization affiliated with Dow Jones & Company had been operating more than 20 programs for minority high-school students to pursue careers in newspaper journalism. The organization…

  3. The Subject of Post-Structuralism: A Reply to Alison Jones.

    ERIC Educational Resources Information Center

    Davies, Bronwyn

    1997-01-01

    Analyzes A. Jones' exposition of the problems her students face in acquiring post-structuralist discourse and the aspects of that problem that Jones attributes to the writings of B. Davies. A focus is on the concept of the post-structuralist "subject." (SLD)

  4. Essential Characteristics of an Highly Resilient Judge: A Case Study of the Honorable Richard Jones

    ERIC Educational Resources Information Center

    Ericksen, Charles Aaron

    2010-01-01

    The purpose of this study was to explore judicial resiliency through the personal experiences and perspectives of an experienced trial court judge, the Honorable Richard Jones. This exploratory case study examined the coping skills, traits, and attributes exhibited by Judge Jones over his career and in particular through the experience of…

  5. A New Large-Scale Global Optimization Method and Its Application to Lennard-Jones Problems

    DTIC Science & Technology

    1992-11-01

    stochastic methods. Computational results on Lennard - Jones problems show that the new method is considerably more successful than any other method that...our method does not find as good a solution as has been found by the best special purpose methods for Lennard - Jones problems. This illustrates the inherent difficulty of large scale global optimization.

  6. A new approach to radiative transfer theory using Jones's vectors. I Fundamentals

    NASA Technical Reports Server (NTRS)

    Fymat, A. L.; Vasudevan, R.

    1975-01-01

    Radiative transfer of partially polarized radiation in an anisotropically scattering, inhomogeneous atmosphere containing an arbitrary polydispersion of particles is described using Jones's (1941) amplitude vectors and matrices. This approach exploits the close analogy between the quantum-mechanical states of spin 1/2 systems and the polarization states of electromagnetic radiation described by Jones's vector. The complete equivalence between the transport equation for Jones's vectors and the classical radiative-transfer equation for Stokes's intensity vectors is demonstrated in two independent ways after deriving the transport equations for the polarization coherency matrices and for the quaternions corresponding to the Jones's vectors. A compact-operator formulation of the theory is provided and used to derive the necessary equations for both a local and a global description of the transport of Jones's vectors. The integro-differential equations for the amplitude reflection and transmission matrices are derived and related to the usual corresponding equations.

  7. 33 CFR 165.159 - Safety Zone: New York Air Show at Jones Beach State Park, Wantagh, NY.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Jones Beach State Park, Wantagh, NY. 165.159 Section 165.159 Navigation and Navigable Waters COAST GUARD... § 165.159 Safety Zone: New York Air Show at Jones Beach State Park, Wantagh, NY. (a) Location. The following waters of the Atlantic Ocean off of Jones Beach State Park, Wantagh, NY are designated a safety...

  8. Vere-Jones' self-similar branching model.

    PubMed

    Saichev, A; Sornette, D

    2005-11-01

    Motivated by its potential application to earthquake statistics as well as for its intrinsic interest in the theory of branching processes, we study the exactly self-similar branching process introduced recently by Vere-Jones. This model extends the ETAS class of conditional self-excited branching point-processes of triggered seismicity by removing the problematic need for a minimum (as well as maximum) earthquake size. To make the theory convergent without the need for the usual ultraviolet and infrared cutoffs, the distribution of magnitudes m' of daughters of first-generation of a mother of magnitude m has two branches m < m' with exponent beta - d and m' > m with exponent beta + d, where beta and d are two positive parameters. We investigate the condition and nature of the subcritical, critical, and supercritical regime in this and in an extended version interpolating smoothly between several models. We predict that the distribution of magnitudes of events triggered by a mother of magnitude m over all generations has also two branches m' < m with exponent and with exponent beta - h, with h=d squareroot of (1-s), where s is the fraction of triggered events. This corresponds to a renormalization of the exponent d into h by the hierarchy of successive generations of triggered events. For a significant part of the parameter space, the distribution of magnitudes over a full catalog summed over an average steady flow of spontaneous sources (immigrants) reproduces the distribution of the spontaneous sources with a single branch and is blind to the exponents beta, d of the distribution of triggered events. Since the distribution of earthquake magnitudes is usually obtained with catalogs including many sequences, we conclude that the two branches of the distribution of aftershocks are not directly observable and the model is compatible with real seismic catalogs. In summary, the exactly self-similar Vere-Jones model provides an attractive new approach to model triggered

  9. Update on diagnosis of acute rheumatic fever: 2015 Jones criteria.

    PubMed

    Eroğlu, Ayşe Güler

    2016-03-01

    In the final Jones criteria, different diagnostic criteria were established for the diagnosis of acute rheumatic fever for low risk and moderate-high risk populations. Turkey was found to be compatible with moderate-high risk populations as a result of regional screenings performed in terms of acute rheumatic fever and rheumatic heart disease. The changes in the diagnostic criteria for low-risk populations include subclinical carditis found on echocardiogram as a major criterion in addition to carditis found clinically and a body temperature of 38.5°C and above as a minor criterion. In moderate-high risk populations including Turkey, subclinical carditis found on echocardiogram in addition to clinical carditis is used as a major criterion as a new amendment. In addition, aseptic monoarthritis and polyarthralgia are used as major criteria in addition to migratory arthritis and monoarhtralgia is used as a minor criterion among joint findings. However, differentiation of subclinical carditis from physiological valve regurgitation found in healthy individuals and exclusion of other diseases involving joints when aseptic monoarthritis and polyarthralgia are used as major criteria are very important. In addition, a body temperature of 38°C and above and an erythrocyte sedimentation rate of 30 mm/h and above have been accepted as minor criteria. The diagnostic criteria for the first attack have not been changed; three minor findings have been accepted in presence of previous sterptococcal infection in addition to the old cirteria for recurrent attacks. In the final Jones criteria, it has been recommended that patients who do not fully meet the diagnostic criteria of acute rheumatic fever should be treated as acute rheumatic fever if another diagnosis is not considered and should be followed up with benzathine penicilin prophylaxis for 12 months. It has been decided that these patients be evaluated 12 months later and a decision for continuation or discontinuation of

  10. Vere-Jones' self-similar branching model

    NASA Astrophysics Data System (ADS)

    Saichev, A.; Sornette, D.

    2005-11-01

    Motivated by its potential application to earthquake statistics as well as for its intrinsic interest in the theory of branching processes, we study the exactly self-similar branching process introduced recently by Vere-Jones. This model extends the ETAS class of conditional self-excited branching point-processes of triggered seismicity by removing the problematic need for a minimum (as well as maximum) earthquake size. To make the theory convergent without the need for the usual ultraviolet and infrared cutoffs, the distribution of magnitudes m' of daughters of first-generation of a mother of magnitude m has two branches m'm with exponent β+d , where β and d are two positive parameters. We investigate the condition and nature of the subcritical, critical, and supercritical regime in this and in an extended version interpolating smoothly between several models. We predict that the distribution of magnitudes of events triggered by a mother of magnitude m over all generations has also two branches m'm with exponent β+h , with h=d1-s , where s is the fraction of triggered events. This corresponds to a renormalization of the exponent d into h by the hierarchy of successive generations of triggered events. For a significant part of the parameter space, the distribution of magnitudes over a full catalog summed over an average steady flow of spontaneous sources (immigrants) reproduces the distribution of the spontaneous sources with a single branch and is blind to the exponents β,d of the distribution of triggered events. Since the distribution of earthquake magnitudes is usually obtained with catalogs including many sequences, we conclude that the two branches of the distribution of aftershocks are not directly observable and the model is compatible with real seismic catalogs. In summary, the exactly self-similar Vere-Jones model provides an attractive new approach to model triggered seismicity, which

  11. Vere-Jones' self-similar branching model

    SciTech Connect

    Saichev, A.; Sornette, D.

    2005-11-01

    Motivated by its potential application to earthquake statistics as well as for its intrinsic interest in the theory of branching processes, we study the exactly self-similar branching process introduced recently by Vere-Jones. This model extends the ETAS class of conditional self-excited branching point-processes of triggered seismicity by removing the problematic need for a minimum (as well as maximum) earthquake size. To make the theory convergent without the need for the usual ultraviolet and infrared cutoffs, the distribution of magnitudes m{sup '} of daughters of first-generation of a mother of magnitude m has two branches m{sup '}m with exponent {beta}+d, where {beta} and d are two positive parameters. We investigate the condition and nature of the subcritical, critical, and supercritical regime in this and in an extended version interpolating smoothly between several models. We predict that the distribution of magnitudes of events triggered by a mother of magnitude m over all generations has also two branches m{sup '}m with exponent {beta}+h, with h=d{radical}(1-s), where s is the fraction of triggered events. This corresponds to a renormalization of the exponent d into h by the hierarchy of successive generations of triggered events. For a significant part of the parameter space, the distribution of magnitudes over a full catalog summed over an average steady flow of spontaneous sources (immigrants) reproduces the distribution of the spontaneous sources with a single branch and is blind to the exponents {beta},d of the distribution of triggered events. Since the distribution of earthquake magnitudes is usually obtained with catalogs including many sequences, we conclude that the two branches of the distribution of aftershocks are not directly observable and the model is compatible with real seismic catalogs. In summary, the exactly self-similar Vere-Jones model provides an

  12. Update on diagnosis of acute rheumatic fever: 2015 Jones criteria

    PubMed Central

    Eroğlu, Ayşe Güler

    2016-01-01

    In the final Jones criteria, different diagnostic criteria were established for the diagnosis of acute rheumatic fever for low risk and moderate-high risk populations. Turkey was found to be compatible with moderate-high risk populations as a result of regional screenings performed in terms of acute rheumatic fever and rheumatic heart disease. The changes in the diagnostic criteria for low-risk populations include subclinical carditis found on echocardiogram as a major criterion in addition to carditis found clinically and a body temperature of 38.5°C and above as a minor criterion. In moderate-high risk populations including Turkey, subclinical carditis found on echocardiogram in addition to clinical carditis is used as a major criterion as a new amendment. In addition, aseptic monoarthritis and polyarthralgia are used as major criteria in addition to migratory arthritis and monoarhtralgia is used as a minor criterion among joint findings. However, differentiation of subclinical carditis from physiological valve regurgitation found in healthy individuals and exclusion of other diseases involving joints when aseptic monoarthritis and polyarthralgia are used as major criteria are very important. In addition, a body temperature of 38°C and above and an erythrocyte sedimentation rate of 30 mm/h and above have been accepted as minor criteria. The diagnostic criteria for the first attack have not been changed; three minor findings have been accepted in presence of previous sterptococcal infection in addition to the old cirteria for recurrent attacks. In the final Jones criteria, it has been recommended that patients who do not fully meet the diagnostic criteria of acute rheumatic fever should be treated as acute rheumatic fever if another diagnosis is not considered and should be followed up with benzathine penicilin prophylaxis for 12 months. It has been decided that these patients be evaluated 12 months later and a decision for continuation or discontinuation of

  13. Astronaut Jones donning EMU during space walk simulations for STS-59

    NASA Image and Video Library

    1993-08-16

    Astronaut Thomas D. Jones, mission specialist, dons a space suit prior to participating in contingency space walk simulations at the JSC Weightless Environment Training Facility (WETF). Jones is assisted by Frank Hernandez (left) and suit technician Charles Hudson of Hamilton Standard. Jones suit is weighted to that he can achieve a neutrally buoyant state once under water. Extravehicular tasks are not planned for the STS-59 mission, but a number of chores are rehearsed in case of failure of remote systems to perform those jobs.

  14. Vacancy behavior in a compressed fcc Lennard-Jones crystal

    SciTech Connect

    Beeler, J.R. Jr.

    1981-12-01

    This computer experiment study concerns the determination of the stable vacancy configuration in a compressed fcc Lennard-Jones crystal and the migration of this defect in a compressed crystal. Isotropic and uniaxial compression stress conditions were studied. The isotropic and uniaxial compression magnitudes employed were 0.94 less than or equal to eta less than or equal to 1.5, and 1.0 less than or equal to eta less than or equal to 1.5, respectively. The site-centered vacancy (SCV) was the stable vacancy configuration whenever cubic symmetry was present. This includes all of the isotropic compression cases and the particular uniaxial compression case (eta = ..sqrt..2) that give a bcc structure. In addition, the SCV was the stable configuration for uniaxial compression eta < 1.29. The out-of-plane split vacancy (SV-OP) was the stable vacancy configuration for uniaxial compression 1.29 < eta less than or equal to 1.5 and was the saddle-point configuration for SCV migration when the SCV was the stable form. For eta > 1.20, the SV-OP is an extended defect and, therefore, a saddle point for SV-OP migration could not be determined. The mechanism for the transformation from the SCV to the SV-OP as the stable form at eta = 1.29 appears to be an alternating sign (101) and/or (011) shear process.

  15. Jones index, secret sharing and total quantum dimension

    NASA Astrophysics Data System (ADS)

    Fiedler, Leander; Naaijkens, Pieter; Osborne, Tobias J.

    2017-02-01

    We study the total quantum dimension in the thermodynamic limit of topologically ordered systems. In particular, using the anyons (or superselection sectors) of such models, we define a secret sharing scheme, storing information invisible to a malicious party, and argue that the total quantum dimension quantifies how well we can perform this task. We then argue that this can be made mathematically rigorous using the index theory of subfactors, originally due to Jones and later extended by Kosaki and Longo. This theory provides us with a ‘relative entropy’ of two von Neumann algebras and a quantum channel, and we argue how these can be used to quantify how much classical information two parties can hide form an adversary. We also review the total quantum dimension in finite systems, in particular how it relates to topological entanglement entropy. It is known that the latter also has an interpretation in terms of secret sharing schemes, although this is shown by completely different methods from ours. Our work provides a different and independent take on this, which at the same time is completely mathematically rigorous. This complementary point of view might be beneficial, for example, when studying the stability of the total quantum dimension when the system is perturbed.

  16. Contact angle of sessile drops in Lennard-Jones systems.

    PubMed

    Becker, Stefan; Urbassek, Herbert M; Horsch, Martin; Hasse, Hans

    2014-11-18

    Molecular dynamics simulations are used for studying the contact angle of nanoscale sessile drops on a planar solid wall in a system interacting via the truncated and shifted Lennard-Jones potential. The entire range between total wetting and dewetting is investigated by varying the solid-fluid dispersive interaction energy. The temperature is varied between the triple point and the critical temperature. A correlation is obtained for the contact angle in dependence of the temperature and the dispersive interaction energy. Size effects are studied by varying the number of fluid particles at otherwise constant conditions, using up to 150,000 particles. For particle numbers below 10,000, a decrease of the contact angle is found. This is attributed to a dependence of the solid-liquid surface tension on the droplet size. A convergence to a constant contact angle is observed for larger system sizes. The influence of the wall model is studied by varying the density of the wall. The effective solid-fluid dispersive interaction energy at a contact angle of θ = 90° is found to be independent of temperature and to decrease linearly with the solid density. A correlation is developed that describes the contact angle as a function of the dispersive interaction, the temperature, and the solid density. The density profile of the sessile drop and the surrounding vapor phase is described by a correlation combining a sigmoidal function and an oscillation term.

  17. Conformation of a Lennard-Jones polymer in explicit solvent

    NASA Astrophysics Data System (ADS)

    Ye, Yuting; Taylor, Mark

    2012-04-01

    The conformation of a polymer chain is solution is coupled to the local structure of the surrounding solvent and can undergo large changes in response to variations in solvent density and temperature. The many-body effects of solvent on the structure of an n-mer chain can be formally mapped to an exact n-body solvation potential. These potentials map the chain-solvent system to a single chain, thereby dramatically reducing the computational complexity of the polymer chain-in-solvent problem. We have recently shown that a pair-decomposition of this n-body potential is valid for short Lennard-Jones (LJ) chains in explicit LJ solvent [1]. Here we use these short chain results to construct solvation potentials for long chains. We present results for the size and intramolecular structure of LJ chains up to length n=400 in LJ solvent at state points spanning the solvent phase diagram (including vapor, liquid, and super-critical regions). In comparison with simulation results for the corresponding full chain-in-solvent system, our solvation potential approach is found to be quantitatively accurate for a wide range of solvent conditions and chain lengths.[4pt] [1] M.P. Taylor and S.R. Adhikari, J. Chem. Phys. 135, 044903 (2011).

  18. Conformation of a Lennard-Jones polymer in explicit solvent

    NASA Astrophysics Data System (ADS)

    Ye, Yuting; Taylor, Mark

    2011-10-01

    The conformation of a polymer chain is solution is coupled to the local structure of the surrounding solvent and can undergo large changes in response to variations in solvent density and temperature. The many-body effects of solvent on the structure of an n-mer chain can be formally mapped to an exact n-body solvation potential. These potentials map the chain-solvent system to a single chain, thereby dramatically reducing the computational complexity of the polymer chain-in-solvent problem. We have recently shown that a pair-decomposition of this n-body potential is valid for short Lennard-Jones (LJ) chains in explicit LJ solvent [1]. Here we use these short chain results to construct solvation potentials for long chains. We present results for the size and intramolecular structure of LJ chains up to length n=400 in LJ solvent at state points spanning the solvent phase diagram (including vapor, liquid, and super-critical regions). In comparison with simulation results for the corresponding full chain-in-solvent system, our solvation potential approach is found to be quantitatively accurate for a wide range of solvent conditions and chain lengths.[4pt] [1] M.P. Taylor and S.R. Adhikari, J. Chem. Phys. 135, 044903 (2011).

  19. A global optimization approach for Lennard-Jones microclusters

    NASA Astrophysics Data System (ADS)

    Maranas, Costas D.; Floudas, Christodoulos A.

    1992-11-01

    A global optimization approach is proposed for finding the global minimum energy configuration of Lennard-Jones microclusters. First, the original nonconvex total potential energy function, composed by rational polynomials, is transformed to the difference of two convex functions (DC transformation) via a novel procedure performed for each pair potential that constitute the total potential energy function. Then, a decomposition strategy based on the global optimization (GOP) algorithm [C. A. Floudas and V. Visweswaran, Comput. Chem. Eng. 14, 1397 (1990); V. Visweswaran and C. A. Floudas, ibid. 14, 1419 (1990); Proc. Process Systems Eng. 1991, I.6.1; C. A. Floudas and V. Visweswaran, J. Opt. Theory Appl. (in press)] is designed to provide tight bounds on the global minimum through the solutions of a sequence of relaxed dual subproblems. A number of theoretical results are included which expedite the computational effort by exploiting the special mathematical structure of the problem. The proposed approach attains ɛ convergence to the global minimum in a finite number of iterations. Based on this procedure, global optimum solutions are generated for small microclusters n≤7. For larger clusters 8≤N≤24 tight lower and upper bounds on the global solution are provided serving as excellent initial points for local optimization approaches. Finally, improved lower bounds on the minimum interparticle distance at the global minimum are provided.

  20. Thermally activated escape from a Lennard-Jones potential well

    NASA Astrophysics Data System (ADS)

    Larson, Richard S.; Lightfoot, Edwin J.

    1988-03-01

    The Kramers theory of chemical kinetics is modified in order to describe the escape of particles from a potential well of the Lennard-Jones type, for which there is no well-defined barrier position or curvature. Approximate analytical methods are used to derive from the Fokker-Planck equation two distinct formulas for the escape rate, each valid in a different regime of the friction constant β. The large-β result is seen to be consistent with that obtained from the Smoluchoeski equation, and it shows that the resistance to escape is dominated by a purely diffusive component that causes nonequilibrium effects to be felt well down into the reactant region. On the other hand, the small-β result describes a situation in which diffusional resistance is of minor importance, and the escape rate is determined largely by the characteristics of the well itself. The approximate formulas give a reasonably good picture of the transition between the two kinds of limiting behavior.

  1. Melting transition of Lennard-Jones fluid in cylindrical pores.

    PubMed

    Das, Chandan K; Singh, Jayant K

    2014-05-28

    Three-stage pseudo-supercritical transformation path and multiple-histogram reweighting technique are employed for the determination of solid-liquid coexistence of the Lennard-Jones (12-6) fluid, in a structureless cylindrical pore of radius, R, ranging from 4 to 20 molecular diameters. The Gibbs free energy difference is evaluated using thermodynamic integration method by connecting solid and liquid phases under confinement via one or more intermediate states without any first order phase transition among them. The thermodynamic melting temperature, Tm, is found to oscillate for pore size, R < 8, which is in agreement with the behavior observed for the melting temperature in slit pores. However, Tm for almost all pore sizes is less than the bulk case, which is contrary to the behavior seen for the slit pore. The oscillation in Tm decays at around pore radius R = 8, and beyond that shift in the melting temperature with respect to the bulk case is in line with the prediction of the Gibbs-Thomson equation.

  2. Metastable Lennard-Jones fluids. II. Thermal conductivity.

    PubMed

    Baidakov, Vladimir G; Protsenko, Sergey P

    2014-06-07

    The method of equilibrium molecular dynamics with the use of the Green-Kubo formalism has been used to calculate the thermal conductivity λ in stable and metastable regions of a Lennard-Jones fluid. Calculations have been made in the range of reduced temperatures 0.4 ≤ T* = k(b)T/ε ≤ 2.0 and densities 0.01 ≤ ρ* = ρσ³ ≤ 1.2 on 15 isotherms for 234 states, 130 of which refer to metastable regions: superheated and supercooled liquids, supersaturated vapor. Equations have been built up which describe the dependence of the regular part of the thermal conductivity on temperature and density, and also on temperature and pressure. It has been found that in (p, T) variables in the region of a liquid-gas phase transition a family of lines of constant value of excess thermal conductivity Δλ = λ - λ0, where λ0 is the thermal conductivity of a dilute gas, has an envelope which coincides with the spinodal. Thus, at the approach to the spinodal of a superheated liquid and supersaturated vapor (∂Δλ/∂p)T → ∞, (∂Δλ/∂T)p → ∞.

  3. Melting transition of Lennard-Jones fluid in cylindrical pores

    SciTech Connect

    Das, Chandan K.; Singh, Jayant K.

    2014-05-28

    Three-stage pseudo-supercritical transformation path and multiple-histogram reweighting technique are employed for the determination of solid-liquid coexistence of the Lennard-Jones (12-6) fluid, in a structureless cylindrical pore of radius, R, ranging from 4 to 20 molecular diameters. The Gibbs free energy difference is evaluated using thermodynamic integration method by connecting solid and liquid phases under confinement via one or more intermediate states without any first order phase transition among them. The thermodynamic melting temperature, T{sub m}, is found to oscillate for pore size, R < 8, which is in agreement with the behavior observed for the melting temperature in slit pores. However, T{sub m} for almost all pore sizes is less than the bulk case, which is contrary to the behavior seen for the slit pore. The oscillation in T{sub m} decays at around pore radius R = 8, and beyond that shift in the melting temperature with respect to the bulk case is in line with the prediction of the Gibbs-Thomson equation.

  4. Freezing of Lennard-Jones fluid on a patterned substrate.

    PubMed

    Zhang, Huijun; Peng, Shuming; Mao, Li; Zhou, Xiaosong; Liang, Jianhua; Wan, Chubin; Zheng, Jian; Ju, Xin

    2014-06-01

    Using molecular dynamics simulations, we study freezing of Lennard-Jones particles at commensurate substrate with triangular pattern. Throughout the box particles freeze onto the substrate and form close-packed layers. For the moderately attractive substrates, an intermediate hexatic phase between liquid and crystal is detected in the first two layers where the hexatic-solid freezing process is continuous while, counterintuitively, the liquid-hexatic process is of first order. Moreover, we observe that liquid-hexatic and hexatic-solid transitions shift towards higher temperatures with the attraction strength increasing. By contrast, the liquid-hexatic transition shifts faster than the hexatic-solid process, significantly widening the temperature range of the hexatic phase. When this phenomenon appears, freezing in the bulk always proceeds through a first-order transition at the same temperature. In addition, changes in the average structural order (three-dimensional) of the layers indicate that freezing processes in layers near substrates seem to cost the structural order of the bulk particles in their vicinity, and an intermediate prestructural cloud of medium-ordered particles is always observed before the layering freezing.

  5. US SPACE CAMP CALIFORNIA - DAY CAMP GRAND OPENING WITH KEVIN JONES (WHISMAN SCHOOL) AND LUCRETIA

    NASA Technical Reports Server (NTRS)

    1996-01-01

    US SPACE CAMP CALIFORNIA - DAY CAMP GRAND OPENING WITH KEVIN JONES (WHISMAN SCHOOL) AND LUCRETIA SUTHERLIN (MCNAIR SCHOOL). AMES SPONSORED STUDENTS AND RACHAEL QUIRING (STAFF) - AUTOGRAPH SIGNING BY Astronaut Wally Schirra

  6. Jones and Polansky perform a LiOH Canister changeout on Atlantis' MDK

    NASA Image and Video Library

    2001-02-07

    STS098-345-028 (7-20 February 2001) --- Astronauts Thomas D. Jones, mission specialist, and Mark L. Polansky, pilot, change out lithium hydroxide canisters on the mid deck of the Earth-orbiting Space Shuttle Atlantis.

  7. The Grande Dame of Afro-American Art: Lois Mailou Jones.

    ERIC Educational Resources Information Center

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Lois Mailou Jones, a Black woman painter who blends Western and non-Western aesthetic traditions in her art. The influences of Haitian and African native traditions on her work are discussed. (BJV)

  8. MS Jones installs cables and connectors on U.S. Laboratory / Destiny Module

    NASA Image and Video Library

    2001-02-07

    STS098-330-007 (7-20 February 2001) --- Astronaut Thomas D. Jones, mission specialist, works near the International Space Station (ISS) during one of the three STS-98 sessions of extravehicular activity (EVA).

  9. A Sensible Estimate for the Stability Constant of the Lennard-Jones Potential

    NASA Astrophysics Data System (ADS)

    Yuhjtman, Sergio A.

    2015-09-01

    We show that the stability constant of the Lennard-Jones potential in , , is smaller than 14.316. This is remarkably smaller than the best previously known bound. Our method is very elementary, and probably applicable to other similar potentials such as the Morse potentials. We also improve slightly, in the Lennard-Jones case, the lower bound for the minimum interparticle distance of an optimal n-particle configuration to 0.684.

  10. Solid-liquid transition in polydisperse Lennard-Jones systems

    NASA Astrophysics Data System (ADS)

    Sarkar, Sarmistha; Biswas, Rajib; Santra, Mantu; Bagchi, Biman

    2013-08-01

    We study melting of a face-centered crystalline solid consisting of polydisperse Lennard-Jones spheres with Gaussian polydispersity in size. The phase diagram reproduces the existence of a nearly temperature invariant terminal polydispersity (δt ≃ 0.11), with no signature of reentrant melting. The absence of reentrant melting can be attributed to the influence of the attractive part of the potential upon melting. We find that at terminal polydispersity the fractional density change approaches zero, which seems to arise from vanishingly small compressibility of the disordered phase. At constant temperature and volume fraction the system undergoes a sharp transition from crystalline solid to the disordered amorphous or fluid state with increasing polydispersity. This has been quantified by second- and third-order rotational invariant bond orientational order, as well as by the average inherent structure energy. The translational order parameter also indicates a similar sharp structural change at δ ≃ 0.09 in case of T* = 1.0, ϕ = 0.58. The free energy calculation further supports the sharp nature of the transition. The third-order rotationally invariant bond order shows that with increasing polydispersity, the local cluster favors a more icosahedral arrangement and the system loses its local crystalline symmetry. Interestingly, the value of structure factor S(k) of the amorphous phase at δ ≃ 0.10 (just beyond the solid-liquid transition density at T* = 1) becomes 2.75, which is below the value of 2.85 required for freezing given by the empirical Hansen-Verlet rule of crystallization, well known in the theory of freezing.

  11. Scaling of the dynamics of flexible Lennard-Jones chains.

    PubMed

    Veldhorst, Arno A; Dyre, Jeppe C; Schrøder, Thomas B

    2014-08-07

    The isomorph theory provides an explanation for the so-called power law density scaling which has been observed in many molecular and polymeric glass formers, both experimentally and in simulations. Power law density scaling (relaxation times and transport coefficients being functions of ρ(γ(S)), where ρ is density, T is temperature, and γ(S) is a material specific scaling exponent) is an approximation to a more general scaling predicted by the isomorph theory. Furthermore, the isomorph theory provides an explanation for Rosenfeld scaling (relaxation times and transport coefficients being functions of excess entropy) which has been observed in simulations of both molecular and polymeric systems. Doing molecular dynamics simulations of flexible Lennard-Jones chains (LJC) with rigid bonds, we here provide the first detailed test of the isomorph theory applied to flexible chain molecules. We confirm the existence of isomorphs, which are curves in the phase diagram along which the dynamics is invariant in the appropriate reduced units. This holds not only for the relaxation times but also for the full time dependence of the dynamics, including chain specific dynamics such as the end-to-end vector autocorrelation function and the relaxation of the Rouse modes. As predicted by the isomorph theory, jumps between different state points on the same isomorph happen instantaneously without any slow relaxation. Since the LJC is a simple coarse-grained model for alkanes and polymers, our results provide a possible explanation for why power-law density scaling is observed experimentally in alkanes and many polymeric systems. The theory provides an independent method of determining the scaling exponent, which is usually treated as an empirical scaling parameter.

  12. Scaling of the dynamics of flexible Lennard-Jones chains

    NASA Astrophysics Data System (ADS)

    Veldhorst, Arno A.; Dyre, Jeppe C.; Schrøder, Thomas B.

    2014-08-01

    The isomorph theory provides an explanation for the so-called power law density scaling which has been observed in many molecular and polymeric glass formers, both experimentally and in simulations. Power law density scaling (relaxation times and transport coefficients being functions of ρ ^{γ _S}/T, where ρ is density, T is temperature, and γS is a material specific scaling exponent) is an approximation to a more general scaling predicted by the isomorph theory. Furthermore, the isomorph theory provides an explanation for Rosenfeld scaling (relaxation times and transport coefficients being functions of excess entropy) which has been observed in simulations of both molecular and polymeric systems. Doing molecular dynamics simulations of flexible Lennard-Jones chains (LJC) with rigid bonds, we here provide the first detailed test of the isomorph theory applied to flexible chain molecules. We confirm the existence of isomorphs, which are curves in the phase diagram along which the dynamics is invariant in the appropriate reduced units. This holds not only for the relaxation times but also for the full time dependence of the dynamics, including chain specific dynamics such as the end-to-end vector autocorrelation function and the relaxation of the Rouse modes. As predicted by the isomorph theory, jumps between different state points on the same isomorph happen instantaneously without any slow relaxation. Since the LJC is a simple coarse-grained model for alkanes and polymers, our results provide a possible explanation for why power-law density scaling is observed experimentally in alkanes and many polymeric systems. The theory provides an independent method of determining the scaling exponent, which is usually treated as an empirical scaling parameter.

  13. Solid-liquid transition in polydisperse Lennard-Jones systems.

    PubMed

    Sarkar, Sarmistha; Biswas, Rajib; Santra, Mantu; Bagchi, Biman

    2013-08-01

    We study melting of a face-centered crystalline solid consisting of polydisperse Lennard-Jones spheres with Gaussian polydispersity in size. The phase diagram reproduces the existence of a nearly temperature invariant terminal polydispersity (δ(t) =/~ 0.11), with no signature of reentrant melting. The absence of reentrant melting can be attributed to the influence of the attractive part of the potential upon melting. We find that at terminal polydispersity the fractional density change approaches zero, which seems to arise from vanishingly small compressibility of the disordered phase. At constant temperature and volume fraction the system undergoes a sharp transition from crystalline solid to the disordered amorphous or fluid state with increasing polydispersity. This has been quantified by second- and third-order rotational invariant bond orientational order, as well as by the average inherent structure energy. The translational order parameter also indicates a similar sharp structural change at δ =/~ 0.09 in case of T(*) = 1.0, φ = 0.58. The free energy calculation further supports the sharp nature of the transition. The third-order rotationally invariant bond order shows that with increasing polydispersity, the local cluster favors a more icosahedral arrangement and the system loses its local crystalline symmetry. Interestingly, the value of structure factor S(k) of the amorphous phase at δ =/~ 0.10 (just beyond the solid-liquid transition density at T(*) = 1) becomes 2.75, which is below the value of 2.85 required for freezing given by the empirical Hansen-Verlet rule of crystallization, well known in the theory of freezing.

  14. Energy landscapes of quantum Lennard-Jones solids.

    PubMed

    Chakravarty, Charusita

    2011-06-30

    To generalize inherent structure analysis to understand structural changes in quantum liquids and solids, differences between classical (V(x)) and quantum-corrected (U(qeff)(x)) energy landscapes are estimated as a function of the de Boer parameter (Λ). Path integral simulations of quantum Lennard-Jones solids are performed at zero pressure and a dimensionless reduced temperature of 0.123, corresponding to an absolute temperature of 4.2K. At constant temperature and pressure, Λ is increased from the classical limit of zero to Λ = 0.28, corresponding to para-H(2). Increasing quantum delocalization effects result in a continuous decrease in density and local order but without a transition to a disordered, liquid state. The inherent structure landscape of bulk systems is strongly dependent on density with the energy and stability of crystalline minima decreasing relative to that of amorphous packing minima as the system is stretched. For Λ ≈ 0.23, the volume fluctuations in quantum solids are sufficient to result in sampling of disordered minima while for Λ = 0.28, the underlying classical inherent structures are completely disordered, indicating that the topography of U(qeff)(x) and V(x) are qualitatively different for such values of Λ. To assess the nature of the quantum-corrected energy landscape, effective pair potentials are defined by u(qeff)(r) = -kT ln g(r) using the pair correlation function (g(r)) of the quantum system in the neighborhood of the first peak. Our results show that as Λ increases, the pair potentials become increasingly softer, shallower, and of increasing range with a shifting of the potential minimum to larger distances. For example, the reduction of the entropy of fusion and melting temperatures of quantum solids with increasing Λ are analogous to the changes in thermodynamics of melting seen in classical solids with increasing range and softness of interactions. The energy landscapes associated with such coarse-grained potentials

  15. Cephalometric effects of the Jones Jig appliance followed by fixed appliances in Class II malocclusion treatment

    PubMed Central

    Patel, Mayara Paim; Henriques, José Fernando Castanha; de Freitas, Karina Maria Salvatore; Grec, Roberto Henrique da Costa

    2014-01-01

    Objective The aim of this study was to cephalometrically assess the skeletal and dentoalveolar effects of Class II malocclusion treatment performed with the Jones Jig appliance followed by fixed appliances. Methods The sample comprised 25 patients with Class II malocclusion treated with the Jones Jig appliance followed by fixed appliances, at a mean initial age of 12.90 years old. The mean time of the entire orthodontic treatment was 3.89 years. The distalization phase lasted for 0.85 years, after which the fixed appliance was used for 3.04 years. Cephalograms were used at initial (T1), post-distalization (T2) and final phases of treatment (T3). For intragroup comparison of the three phases evaluated, dependent ANOVA and Tukey tests were used. Results Jones Jig appliance did not interfere in the maxillary and mandibular component and did not change maxillomandibular relationship. Jones Jig appliance promoted distalization of first molars with anchorage loss, mesialization and significant extrusion of first and second premolars, as well as a significant increase in anterior face height at the end of treatment. The majority of adverse effects that occur during intraoral distalization are subsequently corrected during corrective mechanics. Buccal inclination and protrusion of mandibular incisors were identified. By the end of treatment, correction of overjet and overbite was observed. Conclusions Jones Jig appliance promoted distalization of first molars with anchorage loss represented by significant mesial movement and extrusion of first and second premolars, in addition to a significant increase in anterior face height. PMID:25162565

  16. Cephalometric effects of the Jones Jig appliance followed by fixed appliances in Class II malocclusion treatment.

    PubMed

    Patel, Mayara Paim; Henriques, José Fernando Castanha; Freitas, Karina Maria Salvatore; Grec, Roberto Henrique da Costa

    2014-01-01

    The aim of this study was to cephalometrically assess the skeletal and dentoalveolar effects of Class II malocclusion treatment performed with the Jones Jig appliance followed by fixed appliances. The sample comprised 25 patients with Class II malocclusion treated with the Jones Jig appliance followed by fixed appliances, at a mean initial age of 12.90 years old. The mean time of the entire orthodontic treatment was 3.89 years. The distalization phase lasted for 0.85 years, after which the fixed appliance was used for 3.04 years. Cephalograms were used at initial (T1), post-distalization (T2) and final phases of treatment (T3). For intragroup comparison of the three phases evaluated, dependent ANOVA and Tukey tests were used. Jones Jig appliance did not interfere in the maxillary and mandibular component and did not change maxillomandibular relationship. Jones Jig appliance promoted distalization of first molars with anchorage loss, mesialization and significant extrusion of first and second premolars, as well as a significant increase in anterior face height at the end of treatment. The majority of adverse effects that occur during intraoral distalization are subsequently corrected during corrective mechanics. Buccal inclination and protrusion of mandibular incisors were identified. By the end of treatment, correction of overjet and overbite was observed. Jones Jig appliance promoted distalization of first molars with anchorage loss represented by significant mesial movement and extrusion of first and second premolars, in addition to a significant increase in anterior face height.

  17. Fiber-based lensless polarization holography for measuring Jones matrix parameters of polarization-sensitive materials.

    PubMed

    Liu, Xuan; Yang, Yang; Han, Lu; Guo, Cheng-Shan

    2017-04-03

    We report a fiber-based lensless holographic imaging system to realize a single-shot measurement of two dimensional (2-D) Jones matrix parameters of polarization-sensitive materials. In this system, a multi-source lensless off-axis Fresnel holographic recording geometry is adopted, and two optical fiber splitters are used to generate the multiple reference and illumination beams required for recording a four-channel angular-multiplexing polarization hologram (AMPH). Using this system and the method described in this paper, spatially resolved Jones matrix parameters of a polarization-sensitive material can be retrieved from one single-shot AMPH. We demonstrate the feasibility of the method by extracting a 2-D Jones matrix of a composite polarizer. Applications of the method to measure the Jones matrix maps of a stressed polymethyl methacrylate sample and a mica fragment are also presented. Benefit from the fiber-based and lensless off-axis holographic design, the system possesses a quite compact configuration, which provides a feasible approach for development of an integrated and portable system to measure Jones matrix parameters of polarization-sensitive materials.

  18. Method of extraction of the Mueller-Jones part out of an experimental Mueller matrix

    NASA Astrophysics Data System (ADS)

    Savenkov, Sergey N.; Marienko, Valeri V.

    1997-05-01

    Properly measured experimental Mueller matrix contains complete information on depolarization, anisotropy properties of studied object and on value of isotropic change of probated radiation intensity by studied object as well. They know that Jones matrix contains complete information on value of isotropic change of probated radiation intensity and on anisotropy properties of studied object. Thus, in the case of absent of depolarization and measurement errors reducing to existence of, so called, overpolarization there exist a one-to-one correspondence between Mueller and Jones matrix. Mueller matrix will then be called a Mueller-Jones matrix. The possibility of extraction of Mueller-Jones part out of any experimental Mueller matrix is extremely important because of following. First, it allows us to obtain everything about depolarization properties of studied object directly. Depolarization is very informative 'object' and now, in the majority, one knows little about its nature and methods of its complete description. Second, one gets the possibility to operate with correspondent Jones matrix to analyze of which there exist the powerful methods such as solving of the spectral problem and application of the decomposition theorem formerly proved by the present authors. The distinctive feature of the method proposed here is that it allows us in the best way to take into consideration the important fact that far from all elements of initial Mueller matrix contains information on depolarization.

  19. Phase diagram of power law and Lennard-Jones systems: Crystal phases

    SciTech Connect

    Travesset, Alex

    2014-10-28

    An extensive characterization of the low temperature phase diagram of particles interacting with power law or Lennard-Jones potentials is provided from Lattice Dynamical Theory. For power law systems, only two lattice structures are stable for certain values of the exponent (or softness) (A15, body centered cube (bcc)) and two more (face centered cubic (fcc), hexagonal close packed (hcp)) are always stable. Among them, only the fcc and bcc are equilibrium states. For Lennard-Jones systems, the equilibrium states are either hcp or fcc, with a coexistence curve in pressure and temperature that shows reentrant behavior. The hcp solid never coexists with the liquid. In all cases analyzed, for both power law and Lennard-Jones potentials, the fcc crystal has higher entropy than the hcp. The role of anharmonic terms is thoroughly analyzed and a general thermodynamic integration to account for them is proposed.

  20. Phase diagram of power law and Lennard-Jones systems: Crystal phases

    SciTech Connect

    Travesset, Alex

    2014-10-28

    An extensive characterization of the low temperature phase diagram of particles interacting with power law or Lennard-Jones potentials is provided from Lattice Dynamical Theory. For power law systems, only two lattice structures are stable for certain values of the exponent (or softness) (A15, body centered cube (bcc)) and two more (face centered cubic (fcc), hexagonal close packed (hcp)) are always stable. Among them, only the fcc and bcc are equilibrium states. For Lennard-Jones systems, the equilibrium states are either hcp or fcc, with a coexistence curve in pressure and temperature that shows reentrant behavior. The hcp solid never coexists with the liquid. In all cases analyzed, for both power law and Lennard-Jones potentials, the fcc crystal has higher entropy than the hcp. The role of anharmonic terms is thoroughly analyzed and a general thermodynamic integration to account for them is proposed.

  1. Phase diagram of power law and Lennard-Jones systems: Crystal phases

    NASA Astrophysics Data System (ADS)

    Travesset, Alex

    2014-10-01

    An extensive characterization of the low temperature phase diagram of particles interacting with power law or Lennard-Jones potentials is provided from Lattice Dynamical Theory. For power law systems, only two lattice structures are stable for certain values of the exponent (or softness) (A15, body centered cube (bcc)) and two more (face centered cubic (fcc), hexagonal close packed (hcp)) are always stable. Among them, only the fcc and bcc are equilibrium states. For Lennard-Jones systems, the equilibrium states are either hcp or fcc, with a coexistence curve in pressure and temperature that shows reentrant behavior. The hcp solid never coexists with the liquid. In all cases analyzed, for both power law and Lennard-Jones potentials, the fcc crystal has higher entropy than the hcp. The role of anharmonic terms is thoroughly analyzed and a general thermodynamic integration to account for them is proposed.

  2. A Look Back in Time: Sir Robert Jones, 'Father of Modern Orthopaedics'.

    PubMed

    Tham, Wyw; Sng, Smc; Lum, Y M; Chee, Y H

    2014-11-01

    This paper describes the life of Sir Robert Jones, from his humble beginnings as an apprentice of Thomas Smith, to his many contributions to the orthopaedic specialty. Robert Jones' passion and interest in the subject led to its advancement from a specialty that dealt mainly with crippling diseases in children, to that of treating and rehabilitating disabled adults. He revolutionized the practice by integrating the use of plain radiography, and by developing many new surgical and procedural techniques. He largely improved the specialty by publishing many textbooks and papers, and trained many orthopaedic surgeons from within England and internationally. The purpose of this paper seeks to provide a platform for readers to learn about the man behind the Jones fracture and bandage. It will help readers understand how one man's passion for orthopaedics helped transform it into a specialty in its own rights.

  3. Phase diagram of power law and Lennard-Jones systems: crystal phases.

    PubMed

    Travesset, Alex

    2014-10-28

    An extensive characterization of the low temperature phase diagram of particles interacting with power law or Lennard-Jones potentials is provided from Lattice Dynamical Theory. For power law systems, only two lattice structures are stable for certain values of the exponent (or softness) (A15, body centered cube (bcc)) and two more (face centered cubic (fcc), hexagonal close packed (hcp)) are always stable. Among them, only the fcc and bcc are equilibrium states. For Lennard-Jones systems, the equilibrium states are either hcp or fcc, with a coexistence curve in pressure and temperature that shows reentrant behavior. The hcp solid never coexists with the liquid. In all cases analyzed, for both power law and Lennard-Jones potentials, the fcc crystal has higher entropy than the hcp. The role of anharmonic terms is thoroughly analyzed and a general thermodynamic integration to account for them is proposed.

  4. Systematic investigation of theories of transport in the Lennard-Jones fluid

    PubMed Central

    Dyer, Kippi M.; Pettitt, B. M.; Stell, George

    2008-01-01

    Three kinetic theories of transport are investigated for the single-species Lennard-Jones model fluid. Transport coefficients, including diffusion, shear, and bulk viscosity, are calculated from these theories for the Lennard-Jones fluid across the fluid regions of the phase diagram. The results are systematically compared against simulation. It is found that for each transport property considered, there is at least one theoretical result based on approximations that have been systematically derived from a first-principles starting point that is quantitatively useful over a wide range of densities and temperatures. To the authors' knowledge, this article constitutes the first such compendium of results for the Lennard-Jones model fluid that has been assembled. PMID:17249879

  5. Systematic investigation of theories of transport in the Lennard-Jones fluid.

    PubMed

    Dyer, Kippi M; Pettitt, B M; Stell, George

    2007-01-21

    Three kinetic theories of transport are investigated for the single-species Lennard-Jones model fluid. Transport coefficients, including diffusion, shear, and bulk viscosity, are calculated from these theories for the Lennard-Jones fluid across the fluid regions of the phase diagram. The results are systematically compared against simulation. It is found that for each transport property considered, there is at least one theoretical result based on approximations that have been systematically derived from a first-principles starting point that is quantitatively useful over a wide range of densities and temperatures. To the authors' knowledge, this article constitutes the first such compendium of results for the Lennard-Jones model fluid that has been assembled.

  6. Health assessment for Jones Sanitation Landfill (Jones Septic Site), Hyde Park, Dutchess County, New York, Region 2. CERCLIS No. NYD980534556. Preliminary report

    SciTech Connect

    Not Available

    1988-07-07

    The Jones Sanitation Landfill, also known as the Jones Septic Site, is listed on the National Priorities List. From the early 1960s through 1979 the site accepted industrial liquid wastes and sludges. The site now accepts only septic waste collected by commercial firms. Results of environmental sampling indicate that the contaminants of concern at the site include inorganics (e.g., chromium, copper, lead, cadmium, mercury), oil and grease wastes, and several volatile organic chemicals including: 1,1-dichloroethylene; trichloroethylene; trichloroethene, acetone; 1,2,4-trichlorobenzene; chloroform; methylene chloride; and perhaps pentachlorophenol. Based on the available information, the site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via the above-named human exposure pathways.

  7. Return to Play and Performance After Jones Fracture in National Basketball Association Athletes.

    PubMed

    Begly, John P; Guss, Michael; Ramme, Austin J; Karia, Raj; Meislin, Robert J

    2016-07-01

    Basketball players are at risk for foot injuries, including Jones fractures. It is unknown how this injury affects the future play and performance of athletes. National Basketball Association (NBA) players who sustain Jones fractures of the base of the fifth metatarsal have high rates of return to play and do not experience a decrease in performance on return to competition when compared with preinjury and with control-matched peers. Retrospective cohort study. Level 5. Data on 26 elite basketball players with Jones fractures over 19 NBA seasons (1994-1995 to 2012-2013) were obtained from injury reports, press releases, player profiles, and online public databases. Variables included age, body mass index (BMI), player position, experience, and surgical treatment. Individual season statistics pre- and postinjury were collected. Twenty-six controls were identified by matched player position, age, and performance statistics. The mean age at the time of injury was 24.8 years, mean BMI was 24.7 kg/m(2), and the mean experience prior to injury was 4.1 NBA seasons. Return to previous level of competition was achieved by 85% of athletes. There was no change in player efficiency rating (PER) when pre- and postinjury performance was compared. When compared with controls, no decline in PER measured performance was identified. The majority of NBA players sustaining a Jones fracture return to their preinjury level of competition. These elite athletes demonstrate no decrease in performance on their return to play. Jones fractures are well-studied injuries in terms of etiology, diagnosis, and management. However, the effect of these injuries on future performance of athletes is unknown. Using the findings of our study, orthopaedic surgeons may be better prepared to counsel and educate elite athletes who sustain a Jones fracture. © 2015 The Author(s).

  8. Return to Play and Performance After Jones Fracture in National Basketball Association Athletes

    PubMed Central

    Begly, John P.; Guss, Michael; Ramme, Austin J.; Karia, Raj; Meislin, Robert J.

    2015-01-01

    Background: Basketball players are at risk for foot injuries, including Jones fractures. It is unknown how this injury affects the future play and performance of athletes. Hypothesis: National Basketball Association (NBA) players who sustain Jones fractures of the base of the fifth metatarsal have high rates of return to play and do not experience a decrease in performance on return to competition when compared with preinjury and with control-matched peers. Study Design: Retrospective cohort study. Level of Evidence: Level 5. Methods: Data on 26 elite basketball players with Jones fractures over 19 NBA seasons (1994-1995 to 2012-2013) were obtained from injury reports, press releases, player profiles, and online public databases. Variables included age, body mass index (BMI), player position, experience, and surgical treatment. Individual season statistics pre- and postinjury were collected. Twenty-six controls were identified by matched player position, age, and performance statistics. Results: The mean age at the time of injury was 24.8 years, mean BMI was 24.7 kg/m2, and the mean experience prior to injury was 4.1 NBA seasons. Return to previous level of competition was achieved by 85% of athletes. There was no change in player efficiency rating (PER) when pre- and postinjury performance was compared. When compared with controls, no decline in PER measured performance was identified. Conclusion: The majority of NBA players sustaining a Jones fracture return to their preinjury level of competition. These elite athletes demonstrate no decrease in performance on their return to play. Clinical Relevance: Jones fractures are well-studied injuries in terms of etiology, diagnosis, and management. However, the effect of these injuries on future performance of athletes is unknown. Using the findings of our study, orthopaedic surgeons may be better prepared to counsel and educate elite athletes who sustain a Jones fracture. PMID:26627111

  9. The death of John Paul Jones and resurrection as 'father of the US Navy'.

    PubMed

    Weir, Matthew R; Bogle, Lori L; Mackowiak, Philip A

    2010-01-01

    John Paul Jones, 'father of the US Navy', died under mysterious circumstances on July 18, 1792. Although his remains were resurrected and autopsied 113 years later, the cause of his death has yet to be explained fully. In this detailed review of his clinical history and autopsy findings, we conclude, as have others, that Jones died of kidney failure of undermined etiology. Although 'interstitial nephritis' was diagnosed by the prosectors who performed his autopsy, we believe glomerulopathy (possibly IgA nephropathy) was more likely responsible for his kidney failure and that his death was due to a cardiac arrhythmia or some other complication of uremia.

  10. Gingival Enlargement in a Case of Variant Jones Syndrome: a Case Report

    PubMed Central

    DA, Roopa; Singh, Shinkhala; Gupta, Ira; Gopal, Saumiya

    2016-01-01

    Gingival enlargement can be caused by a variety of etiological factors like inflammation, drugs, and systemic diseases or can be presented as a part of a syndrome. One such syndrome is Jones Syndrome, which is associated with gingival enlargement and progressive hearing loss. We present here a case of fifteen-year-old boy with gingival enlargement, hearing loss, and generalized alveolar bone loss and diagnosed as Jones syndrome. The diagnosis was made based on history, clinical, radiographic, and histopathological findings. Gingival enlargement was surgically managed using gingivectomy and no recurrence was observed. The patient showed remarkable esthetical and functional improvement. PMID:26966711

  11. Closed-form equation of state for Lennard-Jones molecules based on perturbation theory

    SciTech Connect

    Bokis, C.P.; Donohue, M.D.

    1995-08-17

    A comparison of virial theory and perturbation theory for spherical molecules is presented. A new equation of state is derived. This new model has the exact second virial coefficient behavior, converges to the correct mean-field behavior at high densities, and successfully interpolates between these two limits. This new equation of state is applied to molecules that interact via the Lennard-Jones potential. Comparison is made with computer simulation results for the configurational energy, the compressibility factor, and the second virial coefficient of Lennard-Jones molecules. 25 refs., 7 figs.

  12. A Lennard-Jones-like perspective on first order transitions in biological helices

    NASA Astrophysics Data System (ADS)

    Oskolkov, Nikolay; Bohr, Jakob

    2013-03-01

    Helical structures with Lennard-Jones self-interactions are studied for optimal conformations. For this purpose, their self-energy is analyzed for extrema with respect to the geometric parameters of the helices. It is found that Lennard-Jones helices exhibit a first order phase transition from a state with large curvature of the helical backbone to one with a small curvature. I.e. from a dense helix to an extended helix. A transition from one helical structure to another is a phenomenon known to take place in self-assembling helices formed in multicomponent solutions with cholesterol.

  13. Retrograde (atrial) dislodgement of a Cross-Jones mitral valve occluder.

    PubMed

    Schachner, A; Vidne, B; Levy, M J

    1979-01-01

    Fatal atrial dislodgement of a lenticular disc occurred seven years after surgery in a 54-year-old patient, who had had a mitral valve replacement with a Cross-Jones prosthesis, for ruptured chordae tendinae. A marked distortion of the titanium ring reinforced silicone rubber lens disc due to material wear was the cause of this complication. From the literature available to us, atrial dislodgement of a prosthetic mitral occluder has not been previously recorded. We therefore intend to recommend elective replacement of the Cross-Jones prosthesis in all patients who have had their artificial valve functioning for more than five years.

  14. Astronaut Thomas Jones anchored to bunk facility while working on computer

    NASA Image and Video Library

    1994-04-14

    STS059-10-011 (9-20 April 1994) --- Astronaut Thomas D. Jones appears to have climbed out of bed right into his work in this onboard 35mm frame. Actually, Jones had anchored himself in the bunk facility while working on one of the onboard computers which transfered data to the ground via modem. The mission specialist was joined in space by five other NASA astronauts for a week and a half of support to the Space Radar Laboratory (SRL-1)/STS-59 mission.

  15. Properties of the two-dimensional heterogeneous Lennard-Jones dimers: An integral equation study

    NASA Astrophysics Data System (ADS)

    Urbic, Tomaz

    2016-11-01

    Structural and thermodynamic properties of a planar heterogeneous soft dumbbell fluid are examined using Monte Carlo simulations and integral equation theory. Lennard-Jones particles of different sizes are the building blocks of the dimers. The site-site integral equation theory in two dimensions is used to calculate the site-site radial distribution functions and the thermodynamic properties. Obtained results are compared to Monte Carlo simulation data. The critical parameters for selected types of dimers were also estimated and the influence of the Lennard-Jones parameters was studied. We have also tested the correctness of the site-site integral equation theory using different closures.

  16. 1919: psychology and psychoanalysis, Cambridge and London - Myers, Jones and MacCurdy.

    PubMed

    Forrester, John

    2008-01-01

    Viewing the reception of psychoanalysis in Britain from Cambridge, the paper examines the intertwining histories of the post-War British Psychological Society and the founding of the British Psycho-Analytical Society, following the initiatives of the two principal psychological entrepreneurs of the era, Charles Myers and Ernest Jones, Reforms in Cambridge in which psychoanalysis played a significant part are analysed, including the foundation of a Clinic for Nervous Diseases and the establishment of a separate Department of Experimental Psychology. The career of J. T. MacCurdy, Jones's student and Lecturer in Psychopathology at Cambridge, is discussed.

  17. Properties of the two-dimensional heterogeneous Lennard-Jones dimers: An integral equation study.

    PubMed

    Urbic, Tomaz

    2016-11-21

    Structural and thermodynamic properties of a planar heterogeneous soft dumbbell fluid are examined using Monte Carlo simulations and integral equation theory. Lennard-Jones particles of different sizes are the building blocks of the dimers. The site-site integral equation theory in two dimensions is used to calculate the site-site radial distribution functions and the thermodynamic properties. Obtained results are compared to Monte Carlo simulation data. The critical parameters for selected types of dimers were also estimated and the influence of the Lennard-Jones parameters was studied. We have also tested the correctness of the site-site integral equation theory using different closures.

  18. Molecular Simulation of the Vapor-Liquid Phase Behavior of Lennard-Jones Mixtures in Porous Solids

    DTIC Science & Technology

    2006-09-01

    is used to simulate Lennard - Jones fluid mixtures at several porosities: 0.9, 0.95, and 0.975. Effects based on the size and the energetics of the...to the bulk fluid behavior, dramatic shifts in the phase envelope were found for even highly porous structures. Both the Lennard - Jones size and energy

  19. PHYTOREMEDIATION OF DREDGED SEDIMENTS: A CASE STUDY AT THE JONES ISLAND CDF

    EPA Science Inventory

    The Jones Island Confined Disposal Facility (CDF) is a 44 acre in-lake area that receives dredged material from Milwaukee Harbor and the surrounding waterways. Some of those materials are contaminated with industrial waste and urban run-off. The CDF is nearing the end of its desi...

  20. Creative Imagination and Subjective Agency in Wynne-Jones' "The Maestro"

    ERIC Educational Resources Information Center

    Cairns, Sue Ann

    2009-01-01

    The Canadian young adult novel "The Maestro" by Tim Wynne-Jones foregrounds the relationship between imagination and subjective agency. While Burl uses his imagination at the beginning to protect himself from his abusive father, his fantasies become dress rehearsals for small performances that allow him to try on new identities and exercise…

  1. Foucault and Colonial Strategy in Douglas C. Jones' "Arrest Sitting Bull"

    ERIC Educational Resources Information Center

    Murphy, Peter G.

    2004-01-01

    "Arrest Sitting Bull," a novel written by Douglas C. Jones that relates the personal stories of individuals involved in the military and the political domination of the Sioux Indian during the period leading to the Sitting Bull killing is described. The incessant quest to establish and maintain control and the integral roles played by fear and…

  2. OXYGEN TRANSFER EFFICIENCY SURVEYS AT THE JONES ISLAND TREATMENT PLANTS - 1985-1988

    EPA Science Inventory

    Ceramic plate diffusers were among the earliest forms of fine pore diffusers used for oxygen transfer in activated sludge treatment. They have been successfully used for over 60 years in the Jones Island West Plant of the Milwaukee Metropolitan Sewerage District and, since initia...

  3. PHYTOREMEDIATION OF DREDGED SEDIMENTS: A CASE STUDY AT THE JONES ISLAND CDF

    EPA Science Inventory

    The Jones Island Confined Disposal Facility (CDF) is a 44 acre in-lake area that receives dredged material from Milwaukee Harbor and the surrounding waterways. Some of those materials are contaminated with industrial waste and urban run-off. The CDF is nearing the end of its desi...

  4. Solid-liquid equilibria and triple points of n-6 Lennard-Jones fluids

    NASA Astrophysics Data System (ADS)

    Ahmed, Alauddin; Sadus, Richard J.

    2009-11-01

    Molecular dynamics simulations are reported for the solid-liquid coexistence properties of n-6 Lennard-Jones fluids, where n =12, 11, 10, 9, 8, and 7. The complete phase behavior for these systems has been obtained by combining these data with vapor-liquid simulations. The influence of n on the solid-liquid coexistence region is compared using relative density difference and miscibility gap calculations. Analytical expressions for the coexistence pressure, liquid, and solid densities as a function of temperature have been determined, which accurately reproduce the molecular simulation data. The triple point temperature, pressure, and liquid and solid densities are estimated. The triple point temperature and pressure scale with respect to 1/n, resulting in simple linear relationships that can be used to determine the pressure and temperature for the limiting ∞-6 Lennard-Jones potential. The simulation data are used to obtain parameters for the Raveché, Mountain, and Streett and Lindemann melting rules, which indicate that they are obeyed by the n-6 Lennard Jones potentials. In contrast, it is demonstrated that the Hansen-Verlet freezing rule is not valid for n-6 Lennard-Jones potentials.

  5. Malaria and the Decline of Ancient Greece: Revisiting the Jones Hypothesis in an Era of Interdisciplinarity

    ERIC Educational Resources Information Center

    Baron, Christopher; Hamlin, Christopher

    2015-01-01

    Between 1906 and 1909 the biologist Ronald Ross and the classicist W.H.S. Jones pioneered interdisciplinary research in biology and history in advancing the claim that malaria had been crucial in the decline of golden-age Greece (fourth century BCE). The idea had originated with Ross, winner of the Nobel Prize for demonstrating the importance of…

  6. Interpreting Error Patterns in Nonword Repetition Tasks: A Commentary on Tamburelli, Jones, Gobet & Pine (2012)

    ERIC Educational Resources Information Center

    Marshall, Chloe R.

    2012-01-01

    The study by Tamburelli, Jones, Gobet, and Pine (2012; henceforth TJGP) is a very welcome addition to the body of work concerning nonword repetition in typical development. TJGP go beyond previous work in considering three syllabic positions--onset, nucleus, and coda--with the aim of investigating how the positional role of phonemes within the…

  7. Enhancing Undergraduates' Capabilities through Team-Based Competitions: The Edward Jones Challenge

    ERIC Educational Resources Information Center

    Umble, Elisabeth J.; Umble, Michael; Artz, Kendall

    2008-01-01

    The Edward Jones Company recently initiated financial sponsorship of team-based competitions in six undergraduate business core classes at Baylor University. The challenges were chosen to take place in an introductory freshman business class, Managerial Accounting, Principles of Marketing, Corporate Finance, Operations Management, and Strategic…

  8. The Representation of Latinos and the Use of Spanish: A Critical Content Analysis of "Skippyjon Jones"

    ERIC Educational Resources Information Center

    Martínez-Roldan, Carmen M.

    2013-01-01

    This study illustrates the presence of Mock Spanish in some English-based picture books and the ways this usage misrepresents Latino people, language, and culture. The author conducted a critical content analysis of five Skippyjon Jones books. Her guiding question was, How is language used, particularly Spanish, in these English texts, and what…

  9. Malaria and the Decline of Ancient Greece: Revisiting the Jones Hypothesis in an Era of Interdisciplinarity

    ERIC Educational Resources Information Center

    Baron, Christopher; Hamlin, Christopher

    2015-01-01

    Between 1906 and 1909 the biologist Ronald Ross and the classicist W.H.S. Jones pioneered interdisciplinary research in biology and history in advancing the claim that malaria had been crucial in the decline of golden-age Greece (fourth century BCE). The idea had originated with Ross, winner of the Nobel Prize for demonstrating the importance of…

  10. Understanding the interfacial behavior in isopycnic Lennard-Jones mixtures by computer simulations.

    PubMed

    Garrido, José Matías; Piñeiro, Manuel M; Mejía, Andrés; Blas, Felipe J

    2016-01-14

    The physical characterization of the singular interfacial behavior of heterogeneous fluid systems is a very important step in preliminary stages of the design process, and also in the subsequent procedures for the determination of the optimal operating conditions. Molar isopycnicity or molar density inversion is a special case of phase equilibrium behavior that directly affects the relative position of phases in heterogeneous mixtures, without being affected by gravitational fields. This work is dedicated to characterize the impact of molar density inversion on the interfacial properties of Lennard-Jones binary mixtures. The results and specific trends of the molar density inversion phenomena on the peculiar calculated composition profiles across the interface and interfacial tensions are explored by using canonical molecular dynamics simulations of the Lennard-Jones binary mixtures. Our results show that the density inversion causes drastic changes in the density profiles of the mixtures. In particular, symmetrical and equal-sized Lennard-Jones mixtures always exhibit desorption along the interfacial zone, i.e. the interfacial concentration profiles show a relative minimum at the interface of the total density profiles that increases when the dispersive energy parameter (ε(ij)) between unlike species decreases. However, as the asymmetry of the Lennard-Jones mixtures increases (σ(i) ≠ σ(j)), the concentration profiles display a relative maximum at the interface, which implies the adsorption of the total density profiles along the interfacial zone.

  11. The Game TV Plays: Or, Why an English Teacher Came to Hate Barnaby Jones.

    ERIC Educational Resources Information Center

    Shaw, Patrick W.

    The message of current popular television shows in which the hero is, or appears to be, a dumb clod (e.g., Archie Bunker, Fred Sanford, Columbo, and Barnaby Jones), apparently is that corruption may be equated with articulation, wealth, and education, while virtue may be equated with poverty and, often, illiteracy. Unfortunately, the effect of…

  12. Impacts of the Jones Act on the Alaska forest products trade.

    Treesearch

    K.C. Jackson; C.W. McKetta

    1986-01-01

    Alaska forest products trade flows for 1982 were studied to determine the effects of the Merchant Marine Act of 1920 (the Jones Act). Information was collected from timber producers, forest product industries, and waterborne shippers in Alaska, British Columbia, and the Pacific Northwest. Trade flows were simulated, using a partial equilibrium model based on resource...

  13. Enhancing Undergraduates' Capabilities through Team-Based Competitions: The Edward Jones Challenge

    ERIC Educational Resources Information Center

    Umble, Elisabeth J.; Umble, Michael; Artz, Kendall

    2008-01-01

    The Edward Jones Company recently initiated financial sponsorship of team-based competitions in six undergraduate business core classes at Baylor University. The challenges were chosen to take place in an introductory freshman business class, Managerial Accounting, Principles of Marketing, Corporate Finance, Operations Management, and Strategic…

  14. The Representation of Latinos and the Use of Spanish: A Critical Content Analysis of "Skippyjon Jones"

    ERIC Educational Resources Information Center

    Martínez-Roldan, Carmen M.

    2013-01-01

    This study illustrates the presence of Mock Spanish in some English-based picture books and the ways this usage misrepresents Latino people, language, and culture. The author conducted a critical content analysis of five Skippyjon Jones books. Her guiding question was, How is language used, particularly Spanish, in these English texts, and what…

  15. OXYGEN TRANSFER EFFICIENCY SURVEYS AT THE JONES ISLAND TREATMENT PLANTS - 1985-1988

    EPA Science Inventory

    Ceramic plate diffusers were among the earliest forms of fine pore diffusers used for oxygen transfer in activated sludge treatment. They have been successfully used for over 60 years in the Jones Island West Plant of the Milwaukee Metropolitan Sewerage District and, since initia...

  16. Interpreting Error Patterns in Nonword Repetition Tasks: A Commentary on Tamburelli, Jones, Gobet & Pine (2012)

    ERIC Educational Resources Information Center

    Marshall, Chloe R.

    2012-01-01

    The study by Tamburelli, Jones, Gobet, and Pine (2012; henceforth TJGP) is a very welcome addition to the body of work concerning nonword repetition in typical development. TJGP go beyond previous work in considering three syllabic positions--onset, nucleus, and coda--with the aim of investigating how the positional role of phonemes within the…

  17. STS-131 Flight Control Team in WFCR - Orbit 1 - Flight Director: Richard Jones

    NASA Image and Video Library

    2010-04-12

    JSC2010-E-050680 (12 April 2010) --- The members of the STS-131 Orbit 1 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Richard Jones (second left) is on the front row.

  18. Don't Settle: Leslie Monsalve-Jones--New Mexico State Library

    ERIC Educational Resources Information Center

    Library Journal, 2005

    2005-01-01

    Leslie Monsalve-Jones is a library technician with the New Mexico State Library, responsible for claiming documents that state agencies don't submit. She also maintains the collection and can immediately track down any requested document. In short, she is the kind of worker whose price is above rubies but whose pay is slightly above pebbles. And…

  19. Individual-based model formulation for cutthroat trout, Little Jones Creek, California

    Treesearch

    Steven F. Railsback; Bret C. Harvey

    2001-01-01

    This report contains the detailed formulation of an individual-based model (IBM) of cutthroat trout developed for three study sites on Little Jones Creek, Del Norte County, in northwestern California. The model was designed to support research on relations between habitat and fish population dynamics, the importance of small tributaries to trout populations, and the...

  20. On the Myth of the Crisis of Representation: A Response to Gilbourne, Jones and Jordan

    ERIC Educational Resources Information Center

    Gard, Michael

    2014-01-01

    The author observes that, in "Applied Utility and the Auto-Ethnographic Short Story: Persuasions for, and Illustrations of, Writing Critical Social Science," Gilbourne, Jones and Jordan present claims about why we might choose to represent auto-ethnographic data in a literary form such as short story and for the "potential" or…

  1. Creative Imagination and Subjective Agency in Wynne-Jones' "The Maestro"

    ERIC Educational Resources Information Center

    Cairns, Sue Ann

    2009-01-01

    The Canadian young adult novel "The Maestro" by Tim Wynne-Jones foregrounds the relationship between imagination and subjective agency. While Burl uses his imagination at the beginning to protect himself from his abusive father, his fantasies become dress rehearsals for small performances that allow him to try on new identities and exercise…

  2. 77 FR 59899 - Proposed Information Collection; Comment Request; Coastal Zone Management Act Walter B. Jones and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... Zone Management Act Walter B. Jones and NOAA Excellence Awards AGENCY: National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Notice. SUMMARY: The Department of Commerce, as part of its continuing... Nedelka, (301) 713-3155 ext. 127 or Patmarie.Nedelka@noaa.gov . SUPPLEMENTARY INFORMATION: I....

  3. Don't Settle: Leslie Monsalve-Jones--New Mexico State Library

    ERIC Educational Resources Information Center

    Library Journal, 2005

    2005-01-01

    Leslie Monsalve-Jones is a library technician with the New Mexico State Library, responsible for claiming documents that state agencies don't submit. She also maintains the collection and can immediately track down any requested document. In short, she is the kind of worker whose price is above rubies but whose pay is slightly above pebbles. And…

  4. Foucault and Colonial Strategy in Douglas C. Jones' "Arrest Sitting Bull"

    ERIC Educational Resources Information Center

    Murphy, Peter G.

    2004-01-01

    "Arrest Sitting Bull," a novel written by Douglas C. Jones that relates the personal stories of individuals involved in the military and the political domination of the Sioux Indian during the period leading to the Sitting Bull killing is described. The incessant quest to establish and maintain control and the integral roles played by fear and…

  5. On the Myth of the Crisis of Representation: A Response to Gilbourne, Jones and Jordan

    ERIC Educational Resources Information Center

    Gard, Michael

    2014-01-01

    The author observes that, in "Applied Utility and the Auto-Ethnographic Short Story: Persuasions for, and Illustrations of, Writing Critical Social Science," Gilbourne, Jones and Jordan present claims about why we might choose to represent auto-ethnographic data in a literary form such as short story and for the "potential" or…

  6. Melting line of the Lennard-Jones system, infinite size, and full potential.

    PubMed

    Mastny, Ethan A; de Pablo, Juan J

    2007-09-14

    Literature estimates of the melting curve of the Lennard-Jones system vary by as much as 10%. The origin of such discrepancies remains unclear. We present precise values for the Lennard-Jones melting temperature, and we examine possible sources of systematic errors in the prediction of melting points, including finite-size and interaction-cutoff effects. A hypothetical thermodynamic integration path is used to find the relative free energies of the solid and liquid phases, for various system sizes, at constant cutoff radius. The solid-liquid relative free energy and melting temperature scale linearly as the inverse of the number of particles, and it is shown that finite-size effects can account for deviations in the melting temperature (from the infinite-size limit) of up to 5%. An extended-ensemble density-of-states method is used to determine free energy changes for each phase as a continuous function of the cutoff radius. The resulting melting temperature predictions exhibit an oscillatory behavior as the cutoff radius is increased. Deviations in the melting temperature (from the full potential limit) arising from a finite cutoff radius are shown to be of comparable magnitude as those resulting from finite-size effects. This method is used to identify melting temperatures at five different pressures, for the infinite-size and full potential Lennard-Jones system. We use our simulation results as references to connect the Lennard-Jones solid equation of state of van der Hoef with the Lennard-Jones fluid equation of state of Johnson. Once the references are applied the two equations of state are used to identify a melting curve. An empirical equation that fits this melting curve is provided. We also report a reduced triple point temperature T(tr)=0.694.

  7. A Sad Journey down History: A Conversation with Judge Nathaniel Jones about Litigating "Milliken v. Bradley I" (1974), 40 Years Later

    ERIC Educational Resources Information Center

    Gooden, Mark A.; Green, Terrance L.

    2016-01-01

    The Honorable Judge Nathaniel Jones litigated the "Milliken v. Bradley I" case before the U.S. District Court and Supreme Court in 1971 and 1974. Nathaniel Jones was born May 12, 1926 in Youngstown, Ohio, and served as the general counsel for the NAACP from 1969-1979. In 1979, President Jimmy Carter nominated Nathaniel Jones to the U.S.…

  8. A Sad Journey down History: A Conversation with Judge Nathaniel Jones about Litigating "Milliken v. Bradley I" (1974), 40 Years Later

    ERIC Educational Resources Information Center

    Gooden, Mark A.; Green, Terrance L.

    2016-01-01

    The Honorable Judge Nathaniel Jones litigated the "Milliken v. Bradley I" case before the U.S. District Court and Supreme Court in 1971 and 1974. Nathaniel Jones was born May 12, 1926 in Youngstown, Ohio, and served as the general counsel for the NAACP from 1969-1979. In 1979, President Jimmy Carter nominated Nathaniel Jones to the U.S.…

  9. Density functional theory for crystal-liquid interfaces of Lennard-Jones fluid.

    PubMed

    Wang, Xin; Mi, Jianguo; Zhong, Chongli

    2013-04-28

    A density functional approach is presented to describe the crystal-liquid interfaces and crystal nucleations of Lennard-Jones fluid. Within the theoretical framework, the modified fundamental measure theory is applied to describe the free energy functional of hard sphere repulsion, and the weighted density method based on first order mean spherical approximation is used to describe the free energy contribution arising from the attractive interaction. The liquid-solid equilibria, density profiles within crystal cells and at liquid-solid interfaces, interfacial tensions, nucleation free energy barriers, and critical cluster sizes are calculated for face-centered-cubic and body-centered-cubic nucleus. Some results are in good agreement with available simulation data, indicating that the present model is quantitatively reliable in describing nucleation thermodynamics of Lennard-Jones fluid.

  10. Anisotropy effect on global minimum structures of clusters: Two-center Lennard-Jones model

    NASA Astrophysics Data System (ADS)

    Feng, Yan; Wu, Jing; Cheng, Longjiu; Liu, Haiyan

    2011-12-01

    Using a two-center Lennard-Jones (2CLJ) model, the simplest anisotropic case, we investigated how anisotropy affects global minimum structures of clusters and obtained some interesting results. The anisotropy parameter, R, is defined as the ratio of the bond length of 2CLJ dimer to the LJ equilibrium pair separation, where a larger R value means higher anisotropy. For low R values, the structures resemble those of the Lennard-Jones atomic clusters. However, as the pairwise interaction becomes more anisotropic, the "magic numbers" change, and several novel cluster patterns emerge as particularly stable structures, and the global minima change from icosahedral, to polyicosahedral and to novel irregular structures. Moreover, increasing the anisotropy effectively softens the 2CLJ potential. Given the general importance of the LJ cluster as a simple model cluster, 2CLJ model can provide a straightforward and useful analysis of the effect of molecular shape on the structures of clusters.

  11. Optically buffered Jones-matrix-based multifunctional optical coherence tomography with polarization mode dispersion correction

    PubMed Central

    Hong, Young-Joo; Makita, Shuichi; Sugiyama, Satoshi; Yasuno, Yoshiaki

    2014-01-01

    Polarization mode dispersion (PMD) degrades the performance of Jones-matrix-based polarization-sensitive multifunctional optical coherence tomography (JM-OCT). The problem is specially acute for optically buffered JM-OCT, because the long fiber in the optical buffering module induces a large amount of PMD. This paper aims at presenting a method to correct the effect of PMD in JM-OCT. We first mathematically model the PMD in JM-OCT and then derive a method to correct the PMD. This method is a combination of simple hardware modification and subsequent software correction. The hardware modification is introduction of two polarizers which transform the PMD into global complex modulation of Jones matrix. Subsequently, the software correction demodulates the global modulation. The method is validated with an experimentally obtained point spread function with a mirror sample, as well as by in vivo measurement of a human retina. PMID:25657888

  12. Molecular theory of thermal conductivity of the Lennard-Jones fluid

    NASA Astrophysics Data System (ADS)

    Eskandari Nasrabad, Afshin; Laghaei, Rozita; Eu, Byung Chan

    2006-02-01

    In this paper the thermal conductivity of the Lennard-Jones fluid is calculated by applying the combination of the density-fluctuation theory, the modified free volume theory of diffusion, and the generic van der Waals equation of state. A Monte Carlo simulation method is used to compute the equilibrium pair-correlation function necessary for computing the mean free volume and the coefficient in the potential-energy and virial contributions to the thermal conductivity. The theoretical results are compared with our own molecular dynamics simulation results and with those reported in the literature. They agree in good accuracy over wide ranges of density and temperature examined in molecular dynamics simulations. Thus the combined theory represents a molecular theory of thermal conductivity of the Lennard-Jones fluid and by extension simple fluids, which enables us to compute the nonequilibrium quantity by means of the Monte Carlo simulations for the equilibrium pair-correlation function.

  13. Anisotropy effect on global minimum structures of clusters: two-center Lennard-Jones model.

    PubMed

    Feng, Yan; Wu, Jing; Cheng, Longjiu; Liu, Haiyan

    2011-12-28

    Using a two-center Lennard-Jones (2CLJ) model, the simplest anisotropic case, we investigated how anisotropy affects global minimum structures of clusters and obtained some interesting results. The anisotropy parameter, R, is defined as the ratio of the bond length of 2CLJ dimer to the LJ equilibrium pair separation, where a larger R value means higher anisotropy. For low R values, the structures resemble those of the Lennard-Jones atomic clusters. However, as the pairwise interaction becomes more anisotropic, the "magic numbers" change, and several novel cluster patterns emerge as particularly stable structures, and the global minima change from icosahedral, to polyicosahedral and to novel irregular structures. Moreover, increasing the anisotropy effectively softens the 2CLJ potential. Given the general importance of the LJ cluster as a simple model cluster, 2CLJ model can provide a straightforward and useful analysis of the effect of molecular shape on the structures of clusters.

  14. Low density shear viscosity of Lennard-Jones chains of variable rigidities.

    PubMed

    Santacreu, S Delage; Galliero, G; Odunlami, M; Boned, C

    2012-11-28

    The zero-density shear viscosity of different types of short Lennard-Jones chains, up to the hexa-decamer, has been evaluated using a non-equilibrium molecular dynamics scheme. Simulations have been performed on chains of variable rigidities going from the fully flexible to the fully rigid chains. Very interestingly, it is found that there exists a universal relation (a power law) between the zero-density viscosity of the Lennard-Jones chains and their radius of gyration whatever the rigidity of the chain and for all tested temperatures (ranging from 2.5 to 6 in reduced units). Furthermore, for the studied range of temperature, it is shown that the zero-density viscosity of both fully flexible chains and fully rigid chains models can be obtained with an accuracy of a few percents knowing only the dimer viscosity and the length of the chain.

  15. Jones matrix formalism for the theory of picosecond shear acoustic pulse detection.

    PubMed

    Mounier, Denis; Picart, Pascal; Babilotte, Philippe; Ruello, Pascal; Breteau, Jean-Marc; Pézeril, Thomas; Vaudel, Gwenaëlle; Kouyaté, Mansour; Gusev, Vitalyi

    2010-03-29

    A theoretical analysis of the transient optical reflectivity of a sample by a normalized Jones matrix is presented. The off-diagonal components of the normalized matrix are identified with the complex rotation of the polarization ellipse. Transient optical polarimetry is a relevant technique to detect shear acoustic strain pulses propagating normally to the surface of an optically isotropic sample. Moreover, polarimetry has a selective sensitivity to shear waves, as this technique cannot detect longitudinal waves that propagate normally to the sample surface.

  16. Bence Jones proteins: Powerful tool for fundamental study of protein chemistry and pathophysiology

    SciTech Connect

    Stevens, F.J.; Schiffer, M.; Solomon, A.

    1991-12-31

    Bence Jones proteins are typically found in patients with monoclonal plasma cell or related B-cell immunoproliferative disorders. Because of their monoclonal origin and resulting chemical homogeneity much of the fundamental information on immunoglobulin structure came initially from their analysis. Amino acid analyses of these components revealed an N-terminal variable (V) and C-terminal constant (C) domain as well as the existence within the V domain of hypervariable segments that account for the specificity and diversity of antibodies. Over the past three decades, the primary structures of hundreds of light chains (complete and partial), from human and other sources, have been determined, aligned, and archived. Bence Jones proteins and V{sub L} dimers were the crystallizable homogeneous proteins which provided much of the early three-dimensional conformational data that helped explain the structural basis of antibody function. Remarkably, a single Bence Jones protein in two solvent systems (low and high ionic strength) exhibited significant differences in the interactions of the two monomeric subunits comprising the dimer, resulting in substantial variation in the structure of the antigen combining site under the two solution conditions. This observation led to a prediction that heterogeneity of domain interactions may contribute to antibody-antigen interactions. Experimental support for this hypothesis has come from comparisons of the detailed structures of antibody-antigen complexes. The interactions at the interface of the V{sub L} dimer are a function of primary structure and solution conditions. Study of these interactions has led to new information on the relationship between protein structure and function and, as discussed below, can account for specific pathophysiological properties associated with Bence Jones proteins.

  17. Modified Jeans instability in Lorentzian dusty self-gravitating plasmas with Lennard-Jones potential

    NASA Astrophysics Data System (ADS)

    Qian, Y. Z.; Chen, H.; Liu, S. Q.

    2014-11-01

    The Jeans instability in self-gravitating plasma with Kappa distributed dust grains is investigated basing on assumption that the mutual interaction among dust grains is governed by Lennard-Jones potential. It is shown that the presence of additional suprathermal particles has significant effects on the range of unstable modes and growth rate of Jeans instability. Compared with Maxwellian scenario, suprathermality stabilized the Jeans instability.

  18. Pressure-energy correlations in liquids. V. Isomorphs in generalized Lennard-Jones systems.

    PubMed

    Schrøder, Thomas B; Gnan, Nicoletta; Pedersen, Ulf R; Bailey, Nicholas P; Dyre, Jeppe C

    2011-04-28

    This series of papers is devoted to identifying and explaining the properties of strongly correlating liquids, i.e., liquids with more than 90% correlation between their virial W and potential energy U fluctuations in the NVT ensemble. Paper IV [N. Gnan et al., J. Chem. Phys. 131, 234504 (2009)] showed that strongly correlating liquids have "isomorphs," which are curves in the phase diagram along which structure, dynamics, and some thermodynamic properties are invariant in reduced units. In the present paper, using the fact that reduced-unit radial distribution functions are isomorph invariant, we derive an expression for the shapes of isomorphs in the WU phase diagram of generalized Lennard-Jones systems of one or more types of particles. The isomorph shape depends only on the Lennard-Jones exponents; thus all isomorphs of standard Lennard-Jones systems (with exponents 12 and 6) can be scaled onto a single curve. Two applications are given. One tests the prediction that the solid-liquid coexistence curve follows an isomorph by comparing to recent simulations by Ahmed and Sadus [J. Chem. Phys. 131, 174504 (2009)]. Excellent agreement is found on the liquid side of the coexistence curve, whereas the agreement is less convincing on the solid side. A second application is the derivation of an approximate equation of state for generalized Lennard-Jones systems by combining the isomorph theory with the Rosenfeld-Tarazona expression for the temperature dependence of the potential energy on isochores. It is shown that the new equation of state agrees well with simulations.

  19. Baby Boy Jones Interactive Case-Based Learning Activity: A Web-Delivered Teaching Strategy.

    PubMed

    Cleveland, Lisa M; Carmona, Elenice Valentim; Paper, Bruce; Solis, Linda; Taylor, Bonnie

    2015-01-01

    Faced with limited resources, nurse educators are challenged with transforming nursing education while preparing enough qualified nurses to meet future demand; therefore, innovative approaches to teaching are needed. In this article, we describe the development of an innovative teaching activity. Baby Boy Jones is a Web-delivered, case-based learning activity focused on neonatal infection. It was created using e-learning authoring software and delivered through a learning management system.

  20. Finite-size scaling of Lennard-Jones droplet formation at fixed density

    NASA Astrophysics Data System (ADS)

    Zierenberg, Johannes; Janke, Wolfhard

    2016-09-01

    We reaccess the droplet condensation-evaporation transition of a three-dimensional Lennard-Jones system upon a temperature change. With the help of parallel multicanonical simulations we obtain precise estimates of the transition temperature and the width of the transition for systems with up to 2048 particles. This allows us to supplement previous observations of finite-size scaling regimes with a clearer picture also for the case of a continuous particle model.

  1. Modified Jeans instability in Lorentzian dusty self-gravitating plasmas with Lennard-Jones potential

    SciTech Connect

    Qian, Y. Z. Chen, H. Liu, S. Q.

    2014-11-15

    The Jeans instability in self-gravitating plasma with Kappa distributed dust grains is investigated basing on assumption that the mutual interaction among dust grains is governed by Lennard-Jones potential. It is shown that the presence of additional suprathermal particles has significant effects on the range of unstable modes and growth rate of Jeans instability. Compared with Maxwellian scenario, suprathermality stabilized the Jeans instability.

  2. Static and Restricted Rigid Rotor Configurations of Three Classical 12-6-Lennard-Jones Particles

    NASA Astrophysics Data System (ADS)

    Rupp, Florian

    2015-03-01

    Motivated by the continuous search for stable geometric configurations of atom and molecule clusters, we analyse the planar evolution of two freely movable point particles around a third immovable one subject to the 12-6-Lennard-Jones potential. This tailors our discussion to systems with one very heavy particle that can be assumed to be permanently at rest in the moving reference frame for the whole ensemble. Relating to Lennard-Jones interactions, we allow all three point particles to take different parameters. This breaks the symmetry conditions that are usually imposed on such systems. Through a classical non-regularized Hamiltonian description of our restricted three particle system, we study the existence of genuine equilibria and rigid rotor solutions around a single axis of rotation. We prove, depending on the choice of the Lennard-Jones parameters, that for these genuine equilibria, collinear alignments and triangular configurations of any shape can occur. Moreover, for the discussed type of relative equilibria a complete classification is provided by proving the existence of rigid rotor configurations in the plane of rotation (collinear cis and trans as well as triangle shaped configurations) and out of the plane of rotation (triangle shaped and flag-like configurations). Furthermore, we show that there are no further rigid rotor solutions of the underlying equations of motion.

  3. Metastability, spectrum, and eigencurrents of the Lennard-Jones-38 network

    SciTech Connect

    Cameron, Maria K.

    2014-11-14

    We develop computational tools for spectral analysis of stochastic networks representing energy landscapes of atomic and molecular clusters. Physical meaning and some properties of eigenvalues, left and right eigenvectors, and eigencurrents are discussed. We propose an approach to compute a collection of eigenpairs and corresponding eigencurrents describing the most important relaxation processes taking place in the system on its way to the equilibrium. It is suitable for large and complex stochastic networks where pairwise transition rates, given by the Arrhenius law, vary by orders of magnitude. The proposed methodology is applied to the network representing the Lennard-Jones-38 cluster created by Wales's group. Its energy landscape has a double funnel structure with a deep and narrow face-centered cubic funnel and a shallower and wider icosahedral funnel. However, the complete spectrum of the generator matrix of the Lennard-Jones-38 network has no appreciable spectral gap separating the eigenvalue corresponding to the escape from the icosahedral funnel. We provide a detailed description of the escape process from the icosahedral funnel using the eigencurrent and demonstrate a superexponential growth of the corresponding eigenvalue. The proposed spectral approach is compared to the methodology of the Transition Path Theory. Finally, we discuss whether the Lennard-Jones-38 cluster is metastable from the points of view of a mathematician and a chemical physicist, and make a connection with experimental works.

  4. Crystallization of a human Bence Jones protein in microgravity using vapor diffusion in capillaries

    NASA Astrophysics Data System (ADS)

    Alvarado, U. R.; DeWitt, C. R.; Shultz, B. B.; Ramsland, P. A.; Edmundson, A. B.

    2001-03-01

    A simple evaporative method in sealed capillaries was used to produce X-ray diffraction quality crystals of a monoclonal human Bence-Jones protein (Sea) in microgravity and at unit gravity. The λ isotypic Bence-Jones protein was purified from the urine of a multiple myeloma patient using ammonium sulfate precipitation, dialysis and cation exchange, followed by gel filtration. Crystals were produced in glass capillaries where water evaporated from the protein solution was absorbed by one or two suitable absorbents. A crystal grown during the 9-day Space Shuttle STS-95 flight measured 8×1.6×1 mm. It was subjected to X-ray diffraction and was found to be orthorhombic ( P2 12 12 1), with unit-cell dimensions of 48.9, 85.2 and 114.0 Å. X-ray data were collected at room temperature and were 98.3% complete to 2.3 Å resolution. Crystals of the same Bence-Jones protein measuring 1.2-2 mm in length were grown in ground-based controls using a high evaporation rate for the first 12 h, followed by a slower evaporation rate for the remainder of the 19-day growth period.

  5. Scaling of the dynamics of flexible Lennard-Jones chains: Effects of harmonic bonds.

    PubMed

    Veldhorst, Arno A; Dyre, Jeppe C; Schrøder, Thomas B

    2015-11-21

    The previous paper [A. A. Veldhorst et al., J. Chem. Phys. 141, 054904 (2014)] demonstrated that the isomorph theory explains the scaling properties of a liquid of flexible chains consisting of ten Lennard-Jones particles connected by rigid bonds. We here investigate the same model with harmonic bonds. The introduction of harmonic bonds almost completely destroys the correlations in the equilibrium fluctuations of the potential energy and the virial. According to the isomorph theory, if these correlations are strong a system has isomorphs, curves in the phase diagram along which structure, dynamics, and the excess entropy are invariant. The Lennard-Jones chain liquid with harmonic bonds does have curves in the phase diagram along which the structure and dynamics are invariant. The excess entropy is not invariant on these curves, which we refer to as "pseudoisomorphs." In particular, this means that Rosenfeld's excess-entropy scaling (the dynamics being a function of excess entropy only) does not apply for the Lennard-Jones chain with harmonic bonds.

  6. The vapour-liquid interface for a Lennard-Jones model of argon-krypton mixtures

    NASA Astrophysics Data System (ADS)

    Lee, D. J.; Telo da Gama, M. M.; Gubbins, K. E.

    We report a molecular dynamics study of the planar vapour-liquid interface for mixtures of Ar and Kr modelled by truncated Lennard-Jones potentials at 115·77 K and at two compositions. The simulations yield the density profiles, surface tension, surface of tension, adsorption, and normal and transverse components of the pressure tensor. Both the Irving-Kirkwood (IK) and Harasima (H) forms of the pressure tensor are calculated. The values of the surface tension calculated by the thermodynamic and mechanical (for both the IK and H pressure tensors) routes are in agreement, but the IK and H pressure tensors yield different values for the surface of tension, as expected. These results are compared with predictions of the mean field theory (MFT) of the interface. The agreement is generally good, the principal differences being due to the fact that the MFT predicts too low a liquid density. The MFT is also used to predict properties of the mixture interface for the full Lennard-Jones potential. For low concentrations of argon, the argon density profile is predicted to be weakly non-monotonic; this effect is larger for the full than for the truncated Lennard-Jones potential.

  7. Jones matrix treatment of electromagnetic wave propagation in anisotropic stratified media

    NASA Astrophysics Data System (ADS)

    Allia, P.; Oldano, C.; Trossi, L.

    1988-05-01

    Light propagation in anisotropic stratified media may be conveniently described, in the quasi-adiabatic limit, by the so-called Jones matrix formalism. In systems like liquid crystals, the quasi adiabatic limit occurs when the director rotates very slightly over distances of the order of the light wavelength. This limit is of relevant interest in many optical devices. As known, the general solution of the Maxwell's equations in anisotropic stratified media may be obtained by using the 4 × 4 Berreman's matrix method. However, as long as the polarization properties of the light transmitted through the medium are concerned, a much simpler approach is possible, which consists in completely neglecting the solutions of the Berreman's equations corresponding to the waves propagating in the backward direction. In this case, the number of differential equations describing light propagation is reduced from 4 to 2. The 2 × 2 matrix introduced in this approximated fromalism is termed the Jones matrix of the problem. In this paper, we show that in general case of oblique incidence of light is possible to properly transform the original Berreman's matrix into a form suitable for reduction to a 2 × 2 Jones matrix.

  8. Metastability, spectrum, and eigencurrents of the Lennard-Jones-38 network.

    PubMed

    Cameron, Maria K

    2014-11-14

    We develop computational tools for spectral analysis of stochastic networks representing energy landscapes of atomic and molecular clusters. Physical meaning and some properties of eigenvalues, left and right eigenvectors, and eigencurrents are discussed. We propose an approach to compute a collection of eigenpairs and corresponding eigencurrents describing the most important relaxation processes taking place in the system on its way to the equilibrium. It is suitable for large and complex stochastic networks where pairwise transition rates, given by the Arrhenius law, vary by orders of magnitude. The proposed methodology is applied to the network representing the Lennard-Jones-38 cluster created by Wales's group. Its energy landscape has a double funnel structure with a deep and narrow face-centered cubic funnel and a shallower and wider icosahedral funnel. However, the complete spectrum of the generator matrix of the Lennard-Jones-38 network has no appreciable spectral gap separating the eigenvalue corresponding to the escape from the icosahedral funnel. We provide a detailed description of the escape process from the icosahedral funnel using the eigencurrent and demonstrate a superexponential growth of the corresponding eigenvalue. The proposed spectral approach is compared to the methodology of the Transition Path Theory. Finally, we discuss whether the Lennard-Jones-38 cluster is metastable from the points of view of a mathematician and a chemical physicist, and make a connection with experimental works.

  9. Report: Independent Sampling Generally Confirms EPA’s Data at the Jones Sanitation Superfund Site in New York

    EPA Pesticide Factsheets

    Report #09-P-0243, September 23, 2009. In April 2008, the OIG obtained groundwater and surface water samples from the Jones Sanitation Superfund Site and nearby areas, and conducted a site inspection.

  10. Range limitation in hip internal rotation and fifth metatarsal stress fractures (Jones fracture) in professional football players.

    PubMed

    Saita, Yoshitomo; Nagao, Masashi; Kawasaki, Takayuki; Kobayashi, Yohei; Kobayashi, Keiji; Nakajima, Hiroki; Takazawa, Yuji; Kaneko, Kazuo; Ikeda, Hiroshi

    2017-04-25

    To identify unknown risk factors associated with fifth metatarsal stress fracture (Jones fracture). A case-controlled study was conducted among male Japanese professional football (soccer) players with (N = 20) and without (N = 40) a history of Jones fracture. Injury history and physical examination data were reviewed, and the two groups were compared. Univariate and multivariate logistic regression controlling for age, leg dominance and body mass index were used to obtain odds ratios (ORs) and 95% confidence intervals (CIs) to describe the association between physical examination data and the presence or absence of Jones fractures. From 2000 to 2014, among 162 professional football club players, 22 (13.6%; 21 Asians and one Caucasian) had a history of Jones fracture. Thirteen out of 22 (60%) had a Jones fracture in their non-dominant leg. The mean range of hip internal rotation (HIR) was restricted in players with a history of Jones fracture [25.9° ± 7.5°, mean ± standard deviation (SD)] compared to those without (40.4° ± 11.1°, P < 0.0001). Logistic regression analyses demonstrated that HIR limitation increased the risk of a Jones fracture (OR = 3.03, 95% CI 1.45-6.33, P = 0.003). Subgroup analysis using data prior to Jones fracture revealed a causal relationship, such that players with a restriction of HIR were at high risk of developing a Jones fracture [Crude OR (95% CI) = 6.66 (1.90-23.29), P = 0.003, Adjusted OR = 9.91 (2.28-43.10), P = 0.002]. In addition, right HIR range limitation increased the risks of developing a Jones fracture in the ipsilateral and the contralateral feet [OR = 3.11 (1.35-7.16) and 2.24 (1.22-4.12), respectively]. Similarly, left HIR range limitation increased the risks in the ipsilateral or the contralateral feet [OR (95% CI) = 4.88 (1.56-15.28) and 2.77 (1.08-7.08), respectively]. The restriction of HIR was associated with an increased risk of developing a Jones fracture. Since the HIR range is a

  11. Constraints on Jones transmission matrices from time-reversal invariance and discrete spatial symmetries

    NASA Astrophysics Data System (ADS)

    Armitage, N. P.

    2014-07-01

    Optical spectroscopies are most often used to probe dynamical correlations in materials, but they are also a probe of symmetry. Polarization anisotropies are of course sensitive to structural anisotropies, but have been much less used as a probe of more exotic symmetry breakings in ordered states. In this paper, a Jones transfer matrix formalism is discussed to infer the existence of exotic broken symmetry states of matter from their electrodynamic response for a full complement of possible broken symmetries including reflection, rotation, rotation reflection, inversion, and time reversal. A specific condition to distinguish the case of macroscopic time-reversal symmetry breaking is particularly important as in a dynamical experiment like optics, one must distinguish reciprocity from time-reversal symmetry as dissipation violates strict time-reversal symmetry of an experiment. Different forms of reciprocity can be distinguished, but only one is a sufficient (but not necessary) condition for macroscopic time-reversal symmetry breaking. I show the constraints that a Jones matrix develops under the presence or absence of such symmetries. These constraints typically appear in the form of an algebra relating matrix elements or overall constraints (transposition, unitarity, hermiticity, normality, etc.) on the form of the Jones matrix. I work out a number of examples including the trivial case of a ferromagnet and the less trivial cases of magnetoelectrics and vector and scalar spin "chiral" states. I show that the formalism can be used to demonstrate that Kerr rotation must be absent in time-reversal symmetric chiral materials. The formalism here is discussed with an eye towards its use in time-domain terahetrz spectroscopy in transmission, but with small modifications it is more generally applicable.

  12. Determination of iron: In the presence of chromium and titanium with the jones reductor

    USGS Publications Warehouse

    Grimaldi, F.S.; Stevens, R.E.; Carron, M.K.

    1943-01-01

    Sulfuric acid solutions of titanous and chromous sulfates, obtained by passage through the Jones reductor, are oxidized by aeration for from 5 to 10 minutes in the presence of a trace of copper sulfate as a catalyst. Ferrous sulfate is essentially unoxidized and is titrated with permanganate after aeration. Best results are obtained by using 0.0003 millimole of copper sulfate in about 300 ml. of solution. Larger quantities of copper sulfate lead to slightly low results when both chromium and titanium are present.

  13. Replica exchange molecular simulation of Lennard-Jones particles in a two-dimensional confined system

    NASA Astrophysics Data System (ADS)

    Doi, Hideo; Yasuoka, Kenji

    2017-05-01

    Confined systems exhibit interesting properties that are applied to the fields of lubrication, adhesion and nanotechnology. The replica exchange molecular simulation method was applied to calculate the phase equilibrium points of Lennard-Jones particles in a two-dimensional confined system. The liquid-solid phase equilibrium points and the solid structure with a dependency of the slit width were determined and the order parameter of the solid structure was analyzed. Such confined systems are shown to be favorable for manipulation of the phase equilibrium points.

  14. Monte Carlo study of the shear modulus at the surface of a Lennard-Jones crystal

    NASA Astrophysics Data System (ADS)

    Eerden, J. P. v. d.; Knops, H. J. F.; Roos, A.

    1992-01-01

    In this paper, we give a microscopic definition of local elastic constants. We apply this to the numerical evaluation of the shear modulus of an interface which is sharp as compared with the interaction range. The algorithm is applied to a study of the (001) face of a face-centered-cubic (fcc) Lennard-Jones crystal. The vanishing of the shear modulus gives an estimate of the melting temperature of the first layer which is well below the bulk triple point. Some theoretical aspects of surface melting are briefly discussed.

  15. Evaluation of Quantum Corrections to Second Virial Coefficient with Lennard-Jones (12-6) Potential

    NASA Astrophysics Data System (ADS)

    Mamedov, B. A.; Somuncu, E.

    2016-10-01

    The efficient method is developed for analytical evalualtion of quantum corrections to second virial coefficient with Lennard-Jones (12-6) potential. The quantum corrections to second virial coefficient played a significant role in the investigation of real gases in the low temperatures range. In this paper, we obtained a series of formula in terms of gamma and exponential integral functions which is one of the useful approaches for analytical evaluation of quantum corrections to second virial coefficient. The calculation results excellently agreement with of the literature data.

  16. Return to Play in National Football League Players After Operative Jones Fracture Treatment.

    PubMed

    Lareau, Craig R; Hsu, Andrew R; Anderson, Robert B

    2016-01-01

    Jones fractures commonly occur in professional athletes and operative treatment remains the standard of care in this patient population. In our clinical experience, an aggressive postoperative rehabilitation protocol for National Football League (NFL) players with an average return to play (RTP) between 8 and 10 weeks can have successful outcomes with few complications. The purpose of this study was to quantify RTP and rate of complications, including nonunion, refracture, and reoperation among a cohort of NFL players with operatively treated Jones fractures. Between 2004 and 2014, 25 consecutive NFL players who underwent acute Jones fracture fixation by a single surgeon were reviewed. Operative treatment for the majority of patients involved fixation with a Jones-specific intramedullary screw and iliac crest bone marrow aspirate with demineralized bone matrix injected at the fracture site. Additionally, our protocol involved the use of noninvasive bone stimulators, application of customized orthoses, and an aggressive patient-specific rehabilitation protocol. Patient demographics were recorded along with position played, seasons played after surgery, RTP, and complications. RTP was defined as the ability to play in a single regular-season NFL game after surgery. At the time of surgery, average age for all patients was 24.0 years and BMI 31.0. Player positions included 8 wide receivers, 4 linebackers, 4 tight ends, 2 defensive tackles, 2 cornerbacks, 1 offensive tackle, 1 center, 1 tackle, 1 defensive end, and 1 quarterback. Seventy-six percent of players underwent operative fixation during their first 3 seasons. Forty-eight percent were diagnosed before or during their rookie (first) season.RTP was 100% for all players and 80% were still playing at time of publication. Three patients (12.0%) refractured and required revision surgery. Time until RTP was influenced by other variables and difficult to measure because many surgeries were performed early in the

  17. Numerical simulation of pool boiling of a Lennard-Jones liquid

    NASA Astrophysics Data System (ADS)

    Inaoka, Hajime; Ito, Nobuyasu

    2013-09-01

    We performed a numerical simulation of pool boiling by a molecular dynamics model. In the simulation, a liquid composed of Lennard-Jones particles in a uniform gravitational field is heated by a heat source at the bottom of the system. The model successfully reproduces the change in regimes of boiling from nucleate boiling to film boiling with the increase of the heat source temperature. We present the pool boiling curve by the model, whose general behavior is consistent with those observed in experiments of pool boiling.

  18. "Smite this sleeping world awake": Edward Burne-Jones and "The legend of the briar rose".

    PubMed

    Rager, Andrea Wolk

    2009-01-01

    Challenging entrenched preconceptions about the supposed escapism and conservatism of Edward Burne-Jones's art, this paper seeks to establish his monumental painted series, "The Legend of the Briar Rose," as a fundamentally radical and confrontational work. Critics have long viewed it as an endorsement of sleepy stasis, antithetical to the political activism espoused by his friend William Morris. By unraveling the intertwining themes of the series -- the transformative dream vision, artistic labor, the decorative mode, and social egalitarianism -- the "Briar Rose" series is revealed instead to be dramatization of the struggle for personal, social, artistic, and even environmental awakening.

  19. Stability limits for the supercooled liquid and superheated crystal of Lennard-Jones particles

    NASA Astrophysics Data System (ADS)

    Loscar, Ernesto S.; Martin, Daniel A.; Grigera, Tomás S.

    2017-07-01

    We have studied the limits of stability in the first order liquid-solid phase transition in a Lennard-Jones system by means of the short-time relaxation method and using the bond-orientational order parameter Q6. These limits are compared with the melting line. We have paid special attention to the supercooled liquid, comparing our results with the point where the free energy cost of forming a nucleating droplet goes to zero. We also indirectly estimate the dimension associated to the critical nucleus at the spinodal, expected to be fractal according to mean field theories of nucleation.

  20. Birefringence and vascular imaging of in vivo human skin by Jones-matrix optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Li, En; Makita, Shuichi; Hong, Young-Joo; Kasaragod, Deepa; Yasuno, Yoshiaki

    2017-02-01

    A customized 1310-nm Jones-matrix optical coherence tomography (JM-OCT) for dermatological investigation was constructed and used for in vivo normal human skin tissue imaging. This system can simultaneously measure the threedimensional depth-resolved local birefringence, complex-correlation based OCT angiography (OCT-A), degree-ofpolarization- uniformity (DOPU) and scattering OCT intensity. By obtaining these optical properties of tissue, the morphology, vasculature, and collagen content of skin can be deduced and visualized. Structures in the deep layers of the epithelium were observed with depth-resolved local birefringence and polarization uniformity images. These results suggest high diagnostic and investigative potential of JM-OCT for dermatology.

  1. STS-134 Flight Controllers on Console - Launch. Flight Director: Richard Jones

    NASA Image and Video Library

    2011-05-16

    JSC2011-E-044079 (16 May 2011) --- Richard Jones, left, views data at the flight director?s console in the shuttle flight control room in Houston?s Mission Control Center as preparations are underway several hundred miles away in Florida for the final launch of Endeavour. Astronaut Barry Wilmore, spacecraft communicator, is at the CAPCOM console for the prelaunch and launch activities. Endeavour lifted off from Pad 39A at NASA's Kennedy Space Center on time at 8:56 a.m. (EDT) on May 16, 2011. Photo credit: NASA

  2. Ornithodoros peruvianus Kohls, Clifford & Jones (Ixodoidea: Argasidae) in Chile: a tentative diagnosis.

    PubMed

    Venzal, J; González-Acuña, Daniel; Mangold, A; Guglielmone, A

    2012-02-01

    Three argasid tick larvae were collected on April 2, 2010, from a common vampire bat, Desmodus rotundus, captured in the Parque Nacional Pan de Azúcar (26°09' S, 70°41' W), Region of Atacama, Chile. The larvae were diagnosed as Ornithodoros, and further comparative analysis showed them to be Ornithodoros peruvianus Kohls, Clifford & Jones or a species close to it. Phylogenetic analysis based on 16S mitochondrial rRNA gene sequences of Ornithodoros species plus four Argas species was carried out to clarify the taxonomic position of the larvae. This is the first finding of ticks parasitizing D. rotundus in Chile.

  3. Precise simulation of the freezing transition of supercritical Lennard-Jones.

    PubMed

    Nayhouse, Michael; Amlani, Ankur M; Orkoulas, G

    2011-10-21

    The fluid-solid transition of the Lennard-Jones model is analyzed along a supercritical isotherm. The analysis is implemented via a simulation method which is based on a modification of the constrained cell model of Hoover and Ree. In the context of hard-sphere freezing, Hoover and Ree simulated the solid phase using a constrained cell model in which each particle is confined within its own Wigner-Seitz cell. Hoover and Ree also proposed a modified cell model by considering the effect of an external field of variable strength. High-field values favor configurations with a single particle per Wigner-Seitz cell and thus stabilize the solid phase. In previous work, a simulation method for freezing transitions, based on constant-pressure simulations of the modified cell model, was developed and tested on a system of hard spheres. In the present work, this method is used to determine the freezing transition of a Lennard-Jones model system on a supercritical isotherm at a reduced temperature of 2. As in the case of hard spheres, constant-pressure simulations of the fully occupied constrained cell model of a system of Lennard-Jones particles indicate a point of mechanical instability at a density which is approximately 70% of the density at close packing. Furthermore, constant-pressure simulations of the modified cell model indicate that as the strength of the field is reduced, the transition from the solid to the fluid is continuous below the mechanical instability point and discontinuous above. The fluid-solid transition of the Lennard-Jones system is obtained by analyzing the field-induced fluid-solid transition of the modified cell model in the high-pressure, zero-field limit. The simulations are implemented under constant pressure using tempering and histogram reweighting techniques. The coexistence pressure and densities are determined through finite-size scaling techniques for first-order phase transitions which are based on analyzing the size-dependent behavior of

  4. Molecular dynamics simulation of graphene on Cu (111) with different Lennard-Jones parameters

    NASA Astrophysics Data System (ADS)

    Sidorenkov, Alexander V.; Kolesnikov, Sergey V.; Saletsky, Alexander M.

    2016-10-01

    The interaction between graphene and copper (111) surface have been investigated using the molecular dynamics simulations. The range of Lennard-Jones parameters which correspond to the binding energies and the binding distances calculated via ab initio methods was found. The dependencies of the binding energy, the binding distance and the graphene thickness on the parameters of the potential and the rotational angle are presented. We have found minima of the binding energy which can be related to experimentally observed Moiré superstructures.

  5. Modified Lennard-Jones model: virial coefficients to the 7th order.

    PubMed

    Ushcats, M V

    2014-06-21

    The modified Lennard-Jones potential, which simplifies the numerical simulations and maintains the realistic behavior of its parent, is proposed to a role of the standard interaction model for both the experimental and theoretical studies. The virial coefficients of this model up to the seventh order have been calculated for the range of temperatures kT/ɛ = 0.3-70. In the computations, a technique has been used, that combines the quadrature integration and Mayer Sampling Monte Carlo method (MSMC). Unlike the original MSMC, this technique does not require the reference coefficients of another potential and can be used in a wide range of temperatures for various interaction models.

  6. Relaxation of surface tension in the liquid-solid interfaces of Lennard-Jones liquids.

    PubMed

    Lukyanov, Alex V; Likhtman, Alexei E

    2013-11-19

    We have established the surface tension relaxation time in the liquid-solid interfaces of Lennard-Jones (LJ) liquids by means of direct measurements in molecular dynamics (MD) simulations. The main result is that the relaxation time is found to be almost independent of the molecular structures and viscosity of the liquids (at 70-fold change) used in our study and lies in such a range that in slow hydrodynamic motion the interfaces are expected to be at equilibrium. The implications of our results for the modeling of dynamic wetting processes and interpretation of dynamic contact angle data are discussed.

  7. Vapour-liquid coexistence of an active Lennard-Jones fluid.

    PubMed

    Prymidis, Vasileios; Paliwal, Siddharth; Dijkstra, Marjolein; Filion, Laura

    2016-09-28

    We study a three-dimensional system of self-propelled Lennard-Jones particles using Brownian dynamics simulations. Using recent theoretical results for active matter, we calculate the pressure and report equations of state for the system. Additionally, we chart the vapour-liquid coexistence and show that the coexistence densities can be well described using simple power laws. Lastly, we demonstrate that our out-of-equilibrium system shows deviations from both the law of rectilinear diameters and the law of corresponding states.

  8. Vapour-liquid coexistence of an active Lennard-Jones fluid

    NASA Astrophysics Data System (ADS)

    Prymidis, Vasileios; Paliwal, Siddharth; Dijkstra, Marjolein; Filion, Laura

    2016-09-01

    We study a three-dimensional system of self-propelled Lennard-Jones particles using Brownian dynamics simulations. Using recent theoretical results for active matter, we calculate the pressure and report equations of state for the system. Additionally, we chart the vapour-liquid coexistence and show that the coexistence densities can be well described using simple power laws. Lastly, we demonstrate that our out-of-equilibrium system shows deviations from both the law of rectilinear diameters and the law of corresponding states.

  9. The two-dimensional monatomic Leonard-Jones system: triple point and critical point

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi; Chen, Li-rong

    2001-07-01

    We introduce a Leonard-Jones (L-J) interaction into the two-dimensional (2D) Collins model, and consider the existence of the holes that are called the molecular fraction. The Gibbs free energy of solid, liquid and gas has been derived. From the Gibbs function we have obtained the whole diagram of the 2D monatomic L-J system, which includes the melting line, vaporization line, sublimation line and the triple point. Also, we have discussed a few properties of the critical point.

  10. Molecular dynamics of homogeneous nucleation in the vapor phase of Lennard-Jones. III. Effect of carrier gas pressure

    NASA Astrophysics Data System (ADS)

    Yasuoka, Kenji; Zeng, X. C.

    2007-03-01

    A molecular dynamics simulation of vapor phase nucleation has been performed with 40 000 Lennard-Jones particles for the target gas and 0-160 000 particles for the carrier gas. Three carrier gas models are adopted, including a soft-core model, a Lennard-Jones model, and a modified Lennard-Jones model in which the attractive interaction can be adjusted. The effect of the carrier-gas pressure is assessed through computing and comparing the rate of nucleation and cluster size distribution. It is found that the effect of the carrier-gas pressure can be strongly dependent on the carrier-gas model. A positive effect (enhancement of the nucleation rate) is found with the soft-core potential model, whereas negligible effect is found with the Lennard-Jones potential model. For the modified Lennard-Jones potential with a weak attractive interaction, the carrier-gas effect is positive. However, the effect is negligible with a stronger attractive interaction between the target and carrier-gas particles. A reason for the negligible effect is that the carrier-gas particles are adsorbed on the cluster surface when the density of target and carrier-gas particles are comparable. When the density of carrier-gas particles are four times that of the target particles, the carrier-gas particles tend to mix with the target particles in the clusters.

  11. A comparison of molecular dynamics and diffuse interface model predictions of Lennard-Jones fluid evaporation

    SciTech Connect

    Barbante, Paolo; Frezzotti, Aldo; Gibelli, Livio

    2014-12-09

    The unsteady evaporation of a thin planar liquid film is studied by molecular dynamics simulations of Lennard-Jones fluid. The obtained results are compared with the predictions of a diffuse interface model in which capillary Korteweg contributions are added to hydrodynamic equations, in order to obtain a unified description of the liquid bulk, liquid-vapor interface and vapor region. Particular care has been taken in constructing a diffuse interface model matching the thermodynamic and transport properties of the Lennard-Jones fluid. The comparison of diffuse interface model and molecular dynamics results shows that, although good agreement is obtained in equilibrium conditions, remarkable deviations of diffuse interface model predictions from the reference molecular dynamics results are observed in the simulation of liquid film evaporation. It is also observed that molecular dynamics results are in good agreement with preliminary results obtained from a composite model which describes the liquid film by a standard hydrodynamic model and the vapor by the Boltzmann equation. The two mathematical model models are connected by kinetic boundary conditions assuming unit evaporation coefficient.

  12. Gait analysis in patients undergoing ACL reconstruction according to Kenneth Jones' technique.

    PubMed

    Bacchini, Massimo; Cademartiri, Carola; Soncini, Giovanni

    2009-08-01

    The anterior cruciate ligament is essential for knee stability, and its injury, both acute and in the case of chronic knee instability, promotes meniscal degenerative alterations, as well as the onset and progression of gonarthrosis. In this retrospective study, young adults engaged in nonprofessional sportive activities undergoing ACL reconstruction by the Kenneth-Jones technique were assessed clinically and with gait analysis, to detect any deficits persisting even after rehabilitation at a follow- up of approximately 6 months. Eight patients who had undergone elective ligament reconstruction by Kenneth-Jones were assessed between the 5th and 7th month postsurgery with clinical-anamnestic investigation, including the Hughston Clinic subjective knee questionnaire and by gait analysis with the EL.I.Te. system. Gait analysis showed a reduction of ACL protection mechanisms during initial stance; furthermore, the operated limb globally exhibited greater difficulty in muscle recruitment. Residual deficits in muscle recruitment, exposing the reconstructed ligament to possible injuries, persist after a rehabilitation program and after resuming ofpre-surgery activities, thus adjustment of the rehabilitative program on the basis of these findings is recommended.

  13. Morse, Lennard-Jones, and Kratzer Potentials: A Canonical Perspective with Applications.

    PubMed

    Walton, Jay R; Rivera-Rivera, Luis A; Lucchese, Robert R; Bevan, John W

    2016-10-12

    Canonical approaches are applied to classic Morse, Lennard-Jones, and Kratzer potentials. Using the canonical transformation generated for the Morse potential as a reference, inverse transformations allow the accurate generation of the Born-Oppenheimer potential for the H2(+) ion, neutral covalently bound H2, van der Waals bound Ar2, and the hydrogen bonded one-dimensional dissociative coordinate in a water dimer. Similar transformations are also generated using the Lennard-Jones and Kratzer potentials as references. Following application of inverse transformations, vibrational eigenvalues generated from the Born-Oppenheimer potentials give significantly improved quantitative comparison with values determined from the original accurately known potentials. In addition, an algorithmic strategy based upon a canonical transformation to the dimensionless form applied to the force distribution associated with a potential is presented. The resulting canonical force distribution is employed to construct an algorithm for deriving accurate estimates for the dissociation energy, the maximum attractive force, and the internuclear separations corresponding to the maximum attractive force and the potential well.

  14. Surface tension of short flexible Lennard-Jones chains: Corresponding states behavior.

    PubMed

    Galliero, Guillaume

    2010-08-21

    Molecular dynamics simulations of surface tensions of short flexible Lennard-Jones chains, composed of 2, 3, 4, and 5 segments, have been performed in this work. Using the simulation results, it is shown that the reduced surface tension depends only on the chain length and the reduced temperature. As a consequence, simple three parameters corresponding states using the acentric factor is shown to yield an excellent estimation of the reduced surface tension of the flexible Lennard-Jones chain fluid model. In addition, it has been noticed that the reduced surface tension of this fluid model is a unique function of the coexisting liquid and vapor reduced densities (i.e., there exist a universal Parachor behavior) for all chain lengths tested. When applied to real fluids, this universal behavior holds rather well for a large class of real species which can be nonspherical, nonlinear, and even polar. Only the surface tension of hydrogen-bonding compounds seems to largely deviate from this universal Parachor behavior. These interesting features of the surface tension, written in appropriate scaled forms, can probably be used to improve molecular models, in particular, those on which modern molecular based equations of state rely on.

  15. Solubility Limits in Lennard-Jones Mixtures: Effects of Disparate Molecule Geometries.

    PubMed

    Dyer, Kippi M; Perkyns, John S; Pettitt, B Montgomery

    2015-07-23

    In order to better understand general effects of the size and energy disparities between macromolecules and solvent molecules in solution, especially for macromolecular constructs self-assembled from smaller molecules, we use the first- and second-order exact bridge diagram extensions of the HNC integral equation theory to investigate single-component, binary, ternary, and quaternary mixtures of Lennard-Jones fluids. For pure fluids, we find that the HNCH3 bridge function integral equation (i.e., exact to third order in density) is necessary to quantitatively predict the pure gas and pure liquid sides of the coexistence region of the phase diagram of the Lennard-Jones fluid. For the mixtures, we find that the HNCH2 bridge function integral equation is sufficient to qualitatively predict solubility in the binary, ternary, and quaternary mixtures, up to the nominal solubility limit. The results, as limiting cases, should be useful to several problems, including accurate phase diagram predictions for complex mixtures, design of self-assembling nanostructures via solvent controls, and the solvent contributions to the conformational behavior of macromolecules in complex fluids.

  16. Birefringence imaging of posterior eye by multi-functional Jones matrix optical coherence tomography

    PubMed Central

    Sugiyama, Satoshi; Hong, Young-Joo; Kasaragod, Deepa; Makita, Shuichi; Uematsu, Sato; Ikuno, Yasushi; Miura, Masahiro; Yasuno, Yoshiaki

    2015-01-01

    A clinical grade prototype of posterior multifunctional Jones matrix optical coherence tomography (JM-OCT) is presented. This JM-OCT visualized depth-localized birefringence in addition to conventional cumulative phase retardation imaging through local Jones matrix analysis. In addition, it simultaneously provides a sensitivity enhanced scattering OCT, a quantitative polarization uniformity contrast, and OCT-based angiography. The probe beam is at 1-μm wavelength band. The measurement speed and the depth-resolution were 100,000 A-lines/s, and 6.6 μm in tissue, respectively. Normal and pathologic eyes are examined and several clinical features are revealed, which includes high birefringence in the choroid and lamina cribrosa, and birefringent layered structure of the sclera. The theoretical details of the depth-localized birefringence imaging and conventional phase retardation imaging are formulated. This formulation indicates that the birefringence imaging correctly measures a depth-localized single-trip phase retardation of a tissue, while the conventional phase retardation can provide correct single-trip phase retardation only for some specific types of samples. PMID:26713208

  17. The potential energy landscape for crystallisation of a Lennard-Jones fluid

    NASA Astrophysics Data System (ADS)

    de Souza, Vanessa K.; Wales, David J.

    2016-07-01

    Crystallisation pathways are explored by direct analysis of the potential energy landscape for a system of Lennard-Jones particles with periodic boundary conditions. A database of minima and transition states linking liquid and crystalline states is constructed using discrete path sampling and the entire potential energy landscape from liquid to crystal is visualised. We demonstrate that there is a strong negative correlation between the number of atoms in the largest crystalline cluster and the potential energy. In common with previous results we find a strong bias towards the growth of FCC rather than HCP clusters, despite a very small potential energy difference. We characterise three types of perfect crystals with very similar energies: pure FCC, pure HCP, and combinations of FCC and HCP layers. There are also many slightly defective crystalline structures. The effect of the simulation box is analysed for a supercell containing 864 atoms. There are low barriers between some of the different crystalline structures via pathways involving sliding layers, and many different defective structures with FCC layers stacked at an angle to the periodic box. Finally, we compare a binary Lennard-Jones system and visualise the potential energy landscape from supercooled liquid to crystal.

  18. The fish and fisheries of Jones Bank and the wider Celtic Sea

    NASA Astrophysics Data System (ADS)

    Martinez, I.; Ellis, J. R.; Scott, B.; Tidd, A.

    2013-10-01

    The Celtic Sea is a diverse fishing ground that supports important commercial fisheries for a range of demersal fish, large and small-bodied pelagic fish and a variety of cephalopods and other shellfish. A regional overview of the main commercial fish stocks of the Celtic Sea and of the fish that occur in the vicinity of Jones Bank are provided through analyses of landings data from English and Welsh vessels, and from scientific trawl surveys. Dedicated smaller scale sampling via trawl surveys combined with baited cameras on and around the Jones Bank were also analysed to investigate the importance of sandbank habitats with attention paid to the differences in the species occurring on the top of the bank in comparison to adjacent off-bank habitats. Official landing statistics for UK (English and Welsh) vessels indicated that the predominant commercial demersal species in ICES Divisions VIIg,h (in terms of quantities landed) were anglerfish, megrim, pollack and skates (Rajidae). There were, however, regional differences in the distribution of fish and fisheries, and the area surrounding Jones Bank (ICES Rectangles 28E1 and 28E2) supports fisheries for megrim, anglerfish, skates, hake, ling and turbot, with otter trawl, gillnet and beam trawl the main gears used. Recent survey data collected with GOV (Grande Ouverture Verticale) trawl from the Celtic Sea (ICES Divisions VIIe-h, 2007-2010) were used to highlight the broad scale distribution of the main fish assemblages in the Celtic Sea. Analyses of the fish and cephalopod catches from these surveys indicated that there were four broad assemblages in the area, including (i) a region around the Cornwall (which will also be partly influenced by the necessity to use rockhopper ground gear on these rough grounds), (ii) the shallower regions of the north-western Celtic Sea (including parts of the Bristol Channel), (iii) the deeper parts of the outer shelf and (iv) the central Celtic Sea. These data also provided

  19. The belated autopsy and identification of an eighteenth century naval hero--the saga of John Paul Jones.

    PubMed

    Rogers, Nikki L; Field, Kenneth; Froede, Richard C; Towne, Bradford

    2004-09-01

    John Paul Jones, the "Father of the American Navy," is known for the battletime assertion that he had "not yet begun to fight." His central role in a triumph of scientific forensic identification more than a century after his death is less known. John Paul Jones died in 1792 and was buried in Paris, France. The location of his grave was lost over time and a search for his corpse began in 1899. Remains matching his physical characteristics and circumstance of burial were discovered in 1905 and returned to the United States for a hero's burial. Some questioned the identification at the time and the major source of identifying information has since been shown to contain false information. The published forensic literature fails to address existing critiques of the identification. We provide a substantive analysis and conclude that the available evidence supports the identification of the unknown remains as those of John Paul Jones.

  20. Transfer coefficients for evaporation of a system with a Lennard-Jones long-range spline potential.

    PubMed

    Ge, Jialin; Kjelstrup, S; Bedeaux, D; Simon, J M; Rousseau, B

    2007-06-01

    Surface transfer coefficients are determined by nonequilibrium molecular dynamics simulations for a Lennard-Jones fluid with a long-range spline potential. In earlier work [A. Røsjorde, J. Colloid Interface Sci. 240, 355 (2001); J. Xu, ibid. 299, 452 (2006)], using a short-range Lennard-Jones spline potential, it was found that the resistivity coefficients to heat and mass transfer agreed rather well with the values predicted by kinetic theory. For the long-range Lennard-Jones spline potential considered in this paper we find significant discrepancies from the values predicted by kinetic theory. In particular the coupling coefficient, and as a consequence the heat of transfer on the vapor side of the surface are much larger. Thermodynamic data for the liquid-vapor equilibrium confirmed the law of corresponding states for the surface, when it is described as an autonomous system. The importance of these findings for modelling phase transitions is discussed.

  1. Hereditary gingival fibromatosis and sensorineural hearing loss in a 42-year-old man with Jones syndrome.

    PubMed

    Kasaboğlu, O; Tümer, C; Balci, S

    2004-01-01

    Hereditary gingival fibromatosis and sensorineural hearing loss in a 42-year-old man with Jones syndrome: Gingival fibromatosis is a rare disease, which can be seen as an isolated condition or associated with some uncommon syndromes. This case report describes the evaluation and treatment of a 42-year-old male patient with hereditary gingival fibromatosis, sensorineural hearing loss, undescended testis and maxillary odontogenic cyst (Jones Syndrome). Six years follow up of the index patient after the surgery revealed no recurrence of the gingival fibromatosis. This report also describes the anamnestic data of the patient's family that showed progressive deafness and gingival enlargement in three generations.

  2. Gunfight at the NOT OK Corral: Reply to "High Noon for Microfinance" by Duvendack and Palmer-Jones (Uncut version).

    PubMed

    Pitt, Mark M

    2012-01-01

    The paper "High Noon for Microfinance Impact Evaluations" by Duvendack and Palmer-Jones replicates the papers of Chemin (2008) and Pitt and Khandker (1998) that estimate the impact of microfinance in Bangladesh. My paper replicates the Duvendack and Palmer-Jones replication and finds so many serious errors in their code and misrepresentations of the methods described in their paper that I conclude that their results are spurious and provide no evidence about the validity of either the papers of Chemin or Pitt and Khandker or on the effectiveness of microfinance.

  3. Polarization aberration modeling via Jones matrix in the context of OPC

    NASA Astrophysics Data System (ADS)

    Zhang, Qiaolin; Song, Hua; Lucas, Kevin

    2007-10-01

    The increasingly stringent demand for shrinkage of IC device dimensions has been pushing the development of new resolution enhancement technologies in micro-lithography. High NA and Ultra-High NA (NA>1.0) applications for low k I imaging strongly demand the adoption of polarized illumination as a resolution enhancement technology since proper illumination polarization configuration can greatly improve the image contrast hence pattern printing fidelity. For polarized illumination to be fully effective, ideally all the components in the optical system should not alter the polarization state during propagation from illuminator to wafer surface. In current OPC modeling tools, it is typically assumed that the amplitude and polarization state of the electric field do not change as it passes through the projection lens pupil. However, in reality, the projection lens pupil of the scanner does change the amplitude and the polarization state to some extent, and ignorance of projection pupil induced polarization state and amplitude changes may cause CD errors which are un-tolerable at the 45nm device generation and beyond. We developed an OPC-deployable modeling approach to model polarization aberration imposed by the projection lens pupil via Jones matrix format. This polarization aberration modeling capability has been integrated into the Synopsys OPC modeling tool, ProGen, and its accuracy and efficiency have been validated by comparing with an industry standard lithography simulator SolidE. Our OPC simulations show that the impact of projection lens pupil polarization aberrations on optical proximity effect (OPE) could be as large as several nanometers, which is not negligible given the extremely stringent CD error budget at 45nm node and beyond. This modeling approach is applicable to arbitrary polarization aberrations imposed by any components in the lithography system that can be characterized in Jones matrix format. Based on an experimentally measured Jones matrix

  4. Dynamics of vacancies in two-dimensional Lennard-Jones crystals

    NASA Astrophysics Data System (ADS)

    Yao, Zhenwei; de la Cruz, Monica Olvera

    2014-12-01

    Vacancies represent an important class of crystallographic defects, and their behaviors can be strongly coupled with relevant material properties. In this work, we study the dynamics of generic n -point vacancies in two-dimensional Lennard-Jones crystals in several thermodynamic states. Simulations reveal the spectrum of distinct, size-dependent vacancy dynamics, including the nonmonotonously varying diffusive mobilities of one-, two- and three-point vacancies, and several healing routines of linear vacancies. Specifically, we numerically observe significantly faster diffusion of the two-point vacancy that can be attributed to its rotational degree of freedom. The high mobility of the two-point vacancies opens the possibility of doping two-point vacancies into atomic materials to enhance atomic migration. The rich physics of vacancies revealed in this study may have implications in the engineering of defects in extensive crystalline materials for desired properties.

  5. L to R: STS-98 Mission Specialist Thomas Jones, Pilot Mark Polansky, and Commander Kenneth Cockrell

    NASA Technical Reports Server (NTRS)

    2001-01-01

    L to R: STS-98 Mission Specialist Thomas Jones, Pilot Mark Polansky, and Commander Kenneth Cockrell greet STS-92 Commander Brian Duffy, Dryden Center Director Kevin Petersen, and AFFTC Commander Major General Richard Reynolds after landing on the runway at Edwards Air Force Base, California, where NASA's Dryden Flight Research Center is located. Space Shuttle Atlantis landed at 12:33 p.m. February 20, 2001, on the runway at Edwards Air Force Base, California, where NASA's Dryden Flight Research Center is located. The mission, which began February 7, logged 5.3 million miles as the shuttle orbited earth while delivering the Destiny science laboratory to the International Space Station. Inclement weather conditions in Florida prompted the decision to land Atlantis at Edwards. The last time a space shuttle landed at Edwards was Oct. 24, 2000.

  6. John Jones, M.D.: Pioneer, Patriot, and Founder of American Surgery

    PubMed Central

    Widmann, Warren D.; Forde, Kenneth A.; Hardy, Mark A.

    2010-01-01

    John Jones was a pioneer of American Surgery. Born in Long Island, New York in 1729, he received his medical degree in France from the University of Rheims. He returned to the colonies and helped to establish the medical school that would later become Columbia University’s College of Physicians and Surgeons where he was appointed the first Professor of Surgery in the New World. He used his position to assert that surgeons trained in America should be familiar with all facets of medicine and not be mere technicians. Before the outbreak of the American Revolution, he wrote a surgical field manual, which was the first medical text published in America. A believer in the principles of the American Revolution, he would go on to count Benjamin Franklin and George Washington as his patients. Despite achieving many firsts in American medicine, his influence on surgical training is his most enduring legacy. PMID:20012608

  7. Feline lymphoplasmacytic stomatitis associated with monoclonal gammopathy and Bence-Jones proteinuria.

    PubMed

    Lyon, K F

    1994-03-01

    Lymphoplasmacytic stomatitis and gingivitis was diagnosed in an 8-year old female domestic shorthair. The cat had evidence of severe generalized inflammation of the oral cavity. Biopsy samples were evaluated and displayed a lichenoid, interface stomatitis which was predominantly lymphoplasmacytic. Serum protein electrophoresis confirmed a monoclonal gammopathy. Urine protein electrophoresis confirmed Bence-Jones proteinuria. Protein electrophoresis was used to diagnose monoclonal gammopathy (the production of a monoclonal immunoglobulin, or paraprotein, which is associated with a characteristic "M" protein spike on serum electrophoresis). Diseases associated with monoclonal gammopathy are similar in the dog and cat. Alkylating agent chemotherapy is used to rapidly reduce paraprotein concentrations in multiple myeloma. Multiple myeloma is the most common disorder associated with monoclonal gammopathy. This condition is less common in the cat, compared to the dog. This report examines the diagnosis and treatment of multiple myeloma in a cat presenting with severe stomatitis.

  8. John Jones, M.D.: pioneer, patriot, and founder of American surgery.

    PubMed

    Griesemer, Adam D; Widmann, Warren D; Forde, Kenneth A; Hardy, Mark A

    2010-04-01

    John Jones was a pioneer of American Surgery. Born in Long Island, New York in 1729, he received his medical degree in France from the University of Rheims. He returned to the colonies and helped to establish the medical school that would later become Columbia University's College of Physicians and Surgeons where he was appointed the first Professor of Surgery in the New World. He used his position to assert that surgeons trained in America should be familiar with all facets of medicine and not be mere technicians. Before the outbreak of the American Revolution, he wrote a surgical field manual, which was the first medical text published in America. A believer in the principles of the American Revolution, he would go on to count Benjamin Franklin and George Washington as his patients. Despite achieving many firsts in American medicine, his influence on surgical training is his most enduring legacy.

  9. Jones matrix analysis of dichroic phase retarders realized in soft matter composite materials.

    PubMed

    Caputo, Roberto; Trebisacce, Ivan; De Sio, Luciano; Umeton, Cesare

    2010-03-15

    Materials showing birefringence and polarization selective absorption (dichroism) affect the polarization state of incoming light in a peculiar way, quite different from the one exhibited by phase retarders like waveplates. In this paper, we report on the characterization of a Polymer LIquid CRYstal Polymer Slices (POLICRYPS) diffraction grating used as a dichroic phase retarder; the dichroic behaviour of the grating is due to the polarization-dependent diffraction efficiency. Experimental data are validated with a theoretical model based on the Jones matrix formalism, while the grating behavior is modeled by means of the dichroic matrix. In this way, the birefringence of the analyzed structure is easily obtained. For comparison purposes, also two systems different from POLICRYPS have been fabricated and tested.

  10. John Paul Jones: An Overlooked Autopsy Finding that May Explain His Terminal Illness.

    PubMed

    Hamrell, Burt B

    2016-03-01

    A finding in the autopsy of John Paul Jones, the American Revolutionary War naval hero, may explain his terminal illness. During his last 2 years, he had a persistent productive cough and dyspnea. Ten days before death, he developed rapidly progressive dependent edema and ascites. He died in France in 1792. His body, preserved in alcohol in a lead coffin, was, in 1905, removed to the United States. Glomerulonephritis was noted on an autopsy, performed in France, but there was no comment then or since about ventricular wall thickness being the same in both ventricles at 5-6 mm. Hypertrophy and dilatation with biventricular failure followed by tissue shrinkage during 113 years in alcohol could have resulted in these ventricular wall findings. Systemic hypertension and left ventricular failure are consistent with his respiratory symptoms complicated perhaps by pulmonary emboli, right ventricular failure with tricuspid regurgitation, peripheral congestion, and jaundice.

  11. STS-98 MS Jones gets ready to drive an M-113 during TCDT

    NASA Technical Reports Server (NTRS)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- A smiling Thomas Jones, one of the mission specialists on STS-98, gets ready to take the driver'''s seat in an M-113 armored carrier, part of emergency egress training at Launch Pad 39A. In the event of an emergency at the pad prior to launch, the carrier could be used to transport the crew to a nearby bunker or farther. The STS-98 crew is at KSC to take part in Terminal Countdown Demonstration Test activities, which also includes a simulated launch countdown. STS-98 is the seventh construction flight to the International Space Station, carrying as payload the U.S. Lab Destiny, a key element in the construction of the ISS.

  12. Accurate freezing and melting equations for the Lennard-Jones system.

    PubMed

    Khrapak, Sergey A; Morfill, Gregor E

    2011-03-07

    Analyzing three approximate methods to locate liquid-solid coexistence in simple systems, an observation is made that all of them predict the same functional dependence of the temperature on density at freezing and melting of the conventional Lennard-Jones (LJ) system. The emerging equations can be written as T=Aρ(4)+Bρ(2) in normalized units. We suggest to determine the values of the coefficients A at freezing and melting from the high-temperature limit, governed by the inverse 12th power repulsive potential. The coefficients B can be determined from the triple point parameters of the LJ fluid. This produces freezing and melting equations which are exact in the high-temperature limit and at the triple point and show remarkably good agreement with numerical simulation data in the intermediate region. © 2011 American Institute of Physics.

  13. Vectorial platform for manipulating the polarization mode train realized with Jones vectors in Mathematica

    NASA Astrophysics Data System (ADS)

    Kim, Tae Wan; Yun, Hee-Joong

    2016-09-01

    A fundamental concept in physics of polarization propagation of electromagnetic waves is newly understood as a cardinal keyword in quantum cryptography transport technology and cosmology. Recently, interactive visualization of the propagation mechanism of polarized electromagnetism in a medium with helicity has received attention from scientists in the age of information and communication. This study presents a new dynamic polarization platform that manipulates the polarization mode train of a transverse electromagnetic wave by using calculations with Jones vectors in the symbolic program Mathematica. The train of polarization modes is converted continuously through a desirable lineup of optical elements in the platform. The platform simulates a propagation process that satisfies Maxwell's two vector equations precisely with helicity in the vectorial nature of the electromagnetic wave.

  14. Phase diagram and universality of the Lennard-Jones gas-liquid system.

    PubMed

    Watanabe, Hiroshi; Ito, Nobuyasu; Hu, Chin-Kun

    2012-05-28

    The gas-liquid phase transition of the three-dimensional Lennard-Jones particles system is studied by molecular dynamics simulations. The gas and liquid densities in the coexisting state are determined with high accuracy. The critical point is determined by the block density analysis of the Binder parameter with the aid of the law of rectilinear diameter. From the critical behavior of the gas-liquid coexisting density, the critical exponent of the order parameter is estimated to be β = 0.3285(7). Surface tension is estimated from interface broadening behavior due to capillary waves. From the critical behavior of the surface tension, the critical exponent of the correlation length is estimated to be ν = 0.63(4). The obtained values of β and ν are consistent with those of the Ising universality class.

  15. Computing Freidlin's Cycles for the Overdamped Langevin Dynamics. Application to the Lennard-Jones-38 Cluster

    NASA Astrophysics Data System (ADS)

    Cameron, M. K.

    2013-08-01

    The large time behavior of a stochastic system with infinitesimally small noise can be described in terms of Freidlin's cycles. We show that if the system is gradient and the potential satisfies certain non-restrictive conditions, the hierarchy of cycles has a structure of a full binary tree, and each cycle is exited via the lowest saddle adjacent to it. Exploiting this property, we propose an algorithm for computing the asymptotic zero-temperature path and building a hierarchy of Freidlin's cycles associated with the transition process between two given local equilibria. This algorithm is suitable for systems with a complex potential energy landscape with numerous minima. We apply it to find the asymptotic zero-temperature path and Freidlin's cycles involved into the transition process between the two lowest minima of the Lennard-Jones cluster of 38 atoms. D. Wales's stochastic network of minima and transition states of this cluster is used as an input.

  16. Nucleation rates of Lennard-Jones clusters from growth and decay simulations

    NASA Astrophysics Data System (ADS)

    Vehkamäki, Hanna; Ford, Ian J.

    2000-08-01

    We have studied singles clusters of Lennard-Jones atoms using a novel Monte Carlo simulation technique. We computed canonical ensemble averages of the grand canonical growth and decay probabilities of the cluster as a function of the cluster size. The critical size is identified as the one for which growth and decay are equally probable. The size and average internal energy the critical cluster was found for different temperatures and vapor chemical potentials. We used this information together with nucleation theorems to predict the behavior of the nucleation rate as function of the two external parameters. Our results are in line with the results found in the literature, and roughly correspond to the predictions of classical theory.

  17. Fluctuations and Local Structure in Two-Dimensional Lennard--Jones Liquid

    NASA Astrophysics Data System (ADS)

    Mitus, A. C.; Orlik, R.; Patashinski, A. Z.; Patrykiejew, A.; Sokolowski, S.; Riefert, O.

    2003-07-01

    We quantify the concept of ensembles of atoms' fluctuations for 2D liquids close to and in the two-phase coexistence region, using a probabilistic method of local structure analysis. Two ensembles are studied: gas-like independent gaussian fluctuations (IGF) A.C. Mitu�, A.Z. Patashinski, A. Patrykiejew, S. Sokolowski, Phys. Rev. B66, 184202 (2002) and a truly solid-like fluctuations (SF) characteristic for a two-dimensional (2D) triangular solid. For a 2D Lennard--Jones (LJ) system simulated using Monte Carlo and molecular dynamics methods those ensembles yield a statistically reliable description of local solid-like structures in the two-phase region. Both ensembles undergo a spectacular breakdown as the density changes. A hypothetical relation of this breakdown to the behaviour of the heat capacity in the two-phase region is proposed.

  18. Relativistic kinematics formulation of the polarization effects of Jones-Mueller matrices.

    PubMed

    Franssens, Ghislain R

    2015-02-01

    The polarization of a partially coherent, transverse electric, electromagnetic plane wave is commonly represented by a Stokes vector. The similarity between Stokes vectors and four-momentum vectors in special relativity (SR) is studied in depth. The set of Stokes vectors naturally possesses a Euclidean and a Lorentzian geometry. The latter is used to express the polarization-altering properties of Jones-Mueller matrices in a simple and elegant way. In particular, it is shown that the action of a diattenuator on a Stokes vector can be understood in terms of the addition law for velocities from SR. An important simplification in the resulting mathematical expressions further arises if the degree of polarization of a Stokes vector is represented by a hyperbolic polarization angle. This then allows us to demonstrate that the output hyperbolic polarization angle is related to a diattenuator hyperbolic polarization angle and the input hyperbolic polarization angle by the hyperbolic law of cosines holding in a hyperbolic triangle.

  19. Evaluation of higher order PMD effects using Jones matrix analytical models: a comparative study

    NASA Astrophysics Data System (ADS)

    Ferreira, M. F.

    2006-04-01

    A comparative study among the Jones matrix analytical models with high-order PMD is presented. The models that make use of an exponential expansion arrested up to second order or consider the dispersion vector as a Taylor series expansion do not give good results in the approximation of high-order PMD effects, because of the nonlimited behavior with respect to frequency of the modulus of their dispersion vectors. On the other hand, the analytical model which describes the dispersion vector as rotating on a circumference in the Stokes space is found to be the most accurate. Moreover, it can be used to obtain an analytical expression of the pulse broadening, which is often chosen as a quality-system parameter.

  20. Platform for Manipulating Polarization Modes Realized with Jones Vectors in MATHEMATICA

    NASA Astrophysics Data System (ADS)

    Choi, Yong-Dae; Kim, Bogyeong; Yun, Hee-Joong

    2015-06-01

    The fundamental conception in physics of the propagation of the electromagnetic wave polarization in matter is newly understood as the cardinal keyword in free-space quantum communication technology and cosmology in astrophysics. Interactive visualization of the propagation mechanism of polarized electromagnetism in a medium with its helicity has accordingly received attention from scientists exploiting the protocol of quantum key distribution (QKD) to guarantee unconditional security in cryptography communication. We have provided a dynamic polarization platform for presenting the polarization modes of a transverse electromagnetic wave, converting the state of polarization through the arrangement of optical elements, using Jones vectors calculations in Methematica. The platform graphically simulates the mechanism of production and propagation of the polarized waves in a medium while satisfying Maxwell's equations.

  1. Variable soft sphere molecular model for inverse-power-law or Lennard-Jones potential

    NASA Astrophysics Data System (ADS)

    Koura, Katsuhisa; Matsumoto, Hiroaki

    1991-10-01

    The variable soft sphere (VSS) molecular model is introduced for both the viscosity and diffusion cross sections (coefficients) to be consistent with those of the inverse-power-law (IPL) or Lennard-Jones (LJ) potential. The VSS model has almost the same analytical and computational simplicity (computation time) as the variable hard sphere (VHS) model in the Monte Carlo simulation of rarefied gas flows. The null-collision Monte Carlo method is used to make comparative calculations for the molecular diffusion in a heat-bath gas and the normal shock wave structure in a simple gas. For the most severe test of the VSS model for the IPL potential, the softest practical model corresponding to the Maxwell molecule is chosen. The agreement in the molecular diffusion and shock wave structure between the VSS model and the IPL or LJ potential is remarkably good.

  2. Eighth to sixteenth virial coefficients of the Lennard-Jones model.

    PubMed

    Feng, Chao; Schultz, Andrew J; Chaudhary, Vipin; Kofke, David A

    2015-07-28

    We calculated virial coefficients BN, 8 ≤ N ≤ 16, of the Lennard-Jones (LJ) model using both the Mayer-sampling Monte Carlo method and direct generation of configurations, with Wheatley's algorithm for summation of clusters. For N = 8, 24 values are reported, and for N = 9, 12 values are reported, both for temperatures T in the range 0.6 ≤ T ≤ 40.0 (in LJ units). For each N in 10 ≤ N ≤ 16, one to four values are reported for 0.6 ≤ T ≤ 0.9. An approximate functional form for the temperature dependence of BN was developed, and fits of LJ BN(T) based on this form are presented for each coefficient, 4 ≤ N ≤ 9, using new and previously reported data.

  3. Melting in 2D Lennard-Jones Systems: What Type of Phase Transition?

    SciTech Connect

    Patashinski, Alexander Z.; Orlik, Rafal; Mitus, Antonio C.; Grzybowski, Bartosz A.; Ratner, Mark A.

    2010-12-09

    A typical configuration of an equilibrium 2D system of 2500 Lennard-Jones particles at melting is found to be a mosaic of crystallites and amorphous clusters. This mosaic significantly changed at times around the period τ of local vibrations, while most particles retain their nearest neighbors for times much longer than τ. In a system of 2500 particles, we found no phase separation for length scales larger than that of a crystallite. With decreasing density, the number of small amorphous clusters increased, and proliferation and percolation of amorphous matter separated the crystalline-ordered parts so that correlations between local order orientations of remote crystallites disappeared. We suggest that the mosaic is a manifestation of diminished stability of the crystalline structure resulting from competition between attraction and repulsion forces.

  4. Solid-liquid critical behavior of a cylindrically confined Lennard-Jones fluid.

    PubMed

    Mochizuki, Kenji; Koga, Kenichiro

    2015-07-28

    Extensive molecular dynamics simulations have been performed to study the phase behavior of Lennard-Jones particles confined in a quasi-one-dimensional hydrophobic nanopore. We provide unambiguous evidence for a solid-liquid critical point by investigating (i) isotherms in the pressure-volume plane, (ii) the spontaneous solid-liquid phase separation below a certain temperature, (iii) diverging heat capacity and isothermal compressibility as a certain point is approached, (iv) continuous change of dynamical and structural properties above the point, (v) the finite-size scaling analysis of the density distribution below and above the point. The result combined with earlier studies of confined water suggests that the solid-liquid critical point is not uncommon in quasi-one- and quasi-two-dimensional fluids.

  5. Droplet growth during vapor-liquid transition in a 2D Lennard-Jones fluid.

    PubMed

    Midya, Jiarul; Das, Subir K

    2017-01-14

    Results for the kinetics of vapor-liquid phase transition have been presented from the molecular dynamics simulations of a single component two-dimensional Lennard-Jones fluid. The phase diagram for the model, primary prerequisite for this purpose, has been obtained via the Monte Carlo simulations. Our focus is on the region very close to the vapor branch of the coexistence curve. Quenches to such region provide morphology that consists of disconnected circular clusters in the vapor background. We identified that these clusters exhibit diffusive motion and grow via sticky collisions among them. The growth follows power-law behavior with time, exponent of which is found to be in nice agreement with a theoretical prediction.

  6. Shortcomings of the standard Lennard-Jones dispersion term in water models, studied with force matching.

    PubMed

    Nicolini, Paolo; Guàrdia, Elvira; Masia, Marco

    2013-11-14

    In this work, ab initio parametrization of water force field is used to get insights into the functional form of empirical potentials to properly model the physics underlying dispersion interactions. We exploited the force matching algorithm to fit the interaction forces obtained with dispersion corrected density functional theory based molecular dynamics simulations. We found that the standard Lennard-Jones interaction potentials poorly reproduce the attractive character of dispersion forces. This drawback can be resolved by accounting for the distinctive short range behavior of dispersion interactions, multiplying the r(-6) term by a damping function. We propose two novel parametrizations of the force field using different damping functions. Structural and dynamical properties of the new models are computed and compared with the ones obtained from the non-damped force field, showing an improved agreement with reference first principle calculations.

  7. Properties of the Lennard-Jones dimeric fluid in two dimensions: an integral equation study.

    PubMed

    Urbic, Tomaz; Dias, Cristiano L

    2014-03-07

    The thermodynamic and structural properties of the planar soft-sites dumbbell fluid are examined by Monte Carlo simulations and integral equation theory. The dimers are built of two Lennard-Jones segments. Site-site integral equation theory in two dimensions is used to calculate the site-site radial distribution functions for a range of elongations and densities and the results are compared with Monte Carlo simulations. The critical parameters for selected types of dimers were also estimated. We analyze the influence of the bond length on critical point as well as tested correctness of site-site integral equation theory with different closures. The integral equations can be used to predict the phase diagram of dimers whose molecular parameters are known.

  8. Dynamics of vacancies in two-dimensional Lennard-Jones crystals.

    PubMed

    Yao, Zhenwei; de la Cruz, Monica Olvera

    2014-12-01

    Vacancies represent an important class of crystallographic defects, and their behaviors can be strongly coupled with relevant material properties. In this work, we study the dynamics of generic n-point vacancies in two-dimensional Lennard-Jones crystals in several thermodynamic states. Simulations reveal the spectrum of distinct, size-dependent vacancy dynamics, including the nonmonotonously varying diffusive mobilities of one-, two- and three-point vacancies, and several healing routines of linear vacancies. Specifically, we numerically observe significantly faster diffusion of the two-point vacancy that can be attributed to its rotational degree of freedom. The high mobility of the two-point vacancies opens the possibility of doping two-point vacancies into atomic materials to enhance atomic migration. The rich physics of vacancies revealed in this study may have implications in the engineering of defects in extensive crystalline materials for desired properties.

  9. Temperature-dependent mechanisms of homogeneous crystal nucleation in quenced Lennard-Jones liquids

    SciTech Connect

    Peng, L.; Morris, James R; Lo, Y. C.

    2008-01-01

    We have observed homogeneous crystal nucleation in Lennard-Jones liquid by molecular dynamics simulations. A clear nucleation time delay has been observed at T=0.677T{sub m} and T=0.629T{sub m} indicating the presence of a barrier, in contrast to recent reports [Trudu et al., Phys. Rev. Lett. 97, 105701 (2006)]. The structure of nuclei observed in the previous results and in the present work is evidence of transient-time dominated nucleation, not of a spinodal. Very rapid nucleation is observed at T=0.484T{sub m}, indicating either a low (but finite) barrier or possibly a spinodal transformation. No spinodal effect has been observed in similar simulations of crystal nucleation in aluminum at any temperature [Aga et al., Phys. Rev. Lett. 96, 245701 (2006)], suggesting that different qualitative behaviors may be possible in what would seem to be similar potentials.

  10. Determination of new Cu+, Cu2+, and Zn2+ Lennard-Jones ion parameters in acetonitrile.

    PubMed

    Torras, Juan; Alemán, Carlos

    2013-09-12

    We present new Lennard-Jones (LJ) parameters for Cu(+), Cu(2+), and Zn(2+) ion-acetonitrile interactions. The adjustment of ion parameters is made to reproduce simultaneously experimental solvation free energy and structural properties, namely ion-N distance and coordination numbers. Initially, the methodology has been validated deriving parameters for well-studied Na(+) and Cl(-) ions in acetonitrile being compared with experimental and theoretical data. The transferability of parameters is checked by the calculation of thermodynamic and structural properties with three different acetonitrile models. The results obtained for transition metal ions show an overall agreement with reference values. The solvation free energy calculated with new LJ trained parameters using a six-site acetonitrile model, and two older three- and six-site acetonitrile models presents, respectively, percent differences of 0.4, 4.8, and 7.3% when compared with experimental values.

  11. Mesoscopic Hamiltonian for the fluctuations of adsorbed Lennard-Jones liquid films.

    PubMed

    Fernández, Eva M; Chacón, Enrique; MacDowell, Luis G; Tarazona, Pedro

    2015-06-01

    We use Monte Carlo simulations of a Lennard-Jones fluid adsorbed on a short-range planar wall substrate to study the fluctuations in the thickness of the wetting layer, and we get a quantitative and consistent characterization of their mesoscopic Hamiltonian, H[ξ]. We have observed important finite-size effects, which were hampering the analysis of previous results obtained with smaller systems. The results presented here support an appealing simple functional form for H[ξ], close but not exactly equal to the theoretical nonlocal proposal made on the basis a generic density-functional analysis by Parry and coworkers. We have analyzed systems under different wetting conditions, as a proof of principle for a method that provides a quantitative bridge between the molecular interactions and the phenomenology of wetting films at mesoscopic scales.

  12. On the establishment of thermal diffusion in binary Lennard-Jones liquids

    NASA Astrophysics Data System (ADS)

    Ferrario, M.; Bonella, S.; Ciccotti, G.

    2016-10-01

    The establishment of thermal diffusion in an Ar-Kr Lennard-Jones mixture is investigated via dynamical non equilibrium molecular dynamics [G. Ciccotti, G. Jacucci, Phys. Rev. Lett. 35, 789 (1975)]. We observe, in particular, the evolution of the density and temperature fields of the system following the onset of the thermal gradient. In stationary conditions, we also compute the Soret coefficient of the mixture. This study confirms that dynamical non equilibrium molecular dynamics is an effective tool to gather information on transient phenomena, even though the full evolution of the mass and energy fluxes associated to the temperature and density fields requires, in this case, a more substantial numerical effort than the one employed here.

  13. New approach to the first-order phase transition of Lennard-Jones fluids.

    PubMed

    Muguruma, Chizuru; Okamoto, Yuko; Mikami, Masuhiro

    2004-04-22

    The multicanonical Monte Carlo method is applied to a bulk Lennard-Jones fluid system to investigate the liquid-solid phase transition. We take the example of a system of 108 argon particles. The multicanonical weight factor we determined turned out to be reliable for the energy range between -7.0 and -4.0 kJ/mol, which corresponds to the temperature range between 60 and 250 K. The expectation values of the thermodynamic quantities obtained from the multicanonical production run by the reweighting techniques exhibit the characteristics of first-order phase transitions between liquid and solid states around 150 K. The present study reveals that the multicanonical algorithm is particularly suitable for analyzing the transition state of the first-order phase transition in detail.

  14. Clustering of Lennard-Jones particles in water: temperature and pressure effects.

    PubMed

    Ferrara, Gastón; McCarthy, Andrés N; Grigera, J Raúl

    2007-09-14

    While the hydrophobic effect is, for many systems, one of the most relevant interactions, it may be said that in the case of biological systems this effect becomes of determinant importance. Although the matter has been analyzed extensively, certain aspects are yet to be elucidated. Hence, the study on the behavior of the hydrophobic effect with temperature, and particularly with pressure deserves further investigation; model systems may help us in the task. We have analyzed the behavior of Lennard-Jones particles in water by means of molecular dynamics simulation under different conditions of size, concentration, temperature, and pressure. Following the formation of particle aggregates we can observe an increase of the hydrophobic effect with temperature and a strong weakening of the effect at high pressures. The results agree with the experimental evidence and show the ability of molecular dynamics simulation to account for the behavior of nonpolar substances under different conditions, provided that the intermolecular interactions used are adequate.

  15. Phase Transitions For Dilute Particle Systems with Lennard-Jones Potential

    NASA Astrophysics Data System (ADS)

    Collevecchio, Andrea; König, Wolfgang; Mörters, Peter; Sidorova, Nadia

    2010-11-01

    We consider a classical dilute particle system in a large box with pair-interaction given by a Lennard-Jones-type potential. The inverse temperature is picked proportionally to the logarithm of the particle density. We identify the free energy per particle in terms of a variational formula and show that this formula exhibits a cascade of phase transitions as the temperature parameter ranges from zero to infinity. Loosely speaking, the particle system separates into spatially distant components in such a way that within each phase all components are of the same size, which is the larger the lower the temperature. The main tool in our proof is a new large deviation principle for sparse point configurations.

  16. Droplet growth during vapor-liquid transition in a 2D Lennard-Jones fluid

    NASA Astrophysics Data System (ADS)

    Midya, Jiarul; Das, Subir K.

    2017-01-01

    Results for the kinetics of vapor-liquid phase transition have been presented from the molecular dynamics simulations of a single component two-dimensional Lennard-Jones fluid. The phase diagram for the model, primary prerequisite for this purpose, has been obtained via the Monte Carlo simulations. Our focus is on the region very close to the vapor branch of the coexistence curve. Quenches to such region provide morphology that consists of disconnected circular clusters in the vapor background. We identified that these clusters exhibit diffusive motion and grow via sticky collisions among them. The growth follows power-law behavior with time, exponent of which is found to be in nice agreement with a theoretical prediction.

  17. Dynamics of vacancies in two-dimensional Lennard-Jones crystals

    NASA Astrophysics Data System (ADS)

    Yao, Zhenwei; Olvera de La Cruz, Monica

    2015-03-01

    Vacancies represent an important class of crystallographic defects, and their behaviors can be strongly coupled with relevant material properties. We report the rich dynamics of vacancies in two-dimensional Lennard-Jones crystals in several thermodynamic states. Specifically, we numerically observe significantly faster diffusion of the 2-point vacancy with two missing particles in comparison with other types of vacancies; it opens the possibility of doping 2-point vacancies into atomic materials to enhance atomic migration. In addition, the resulting dislocations in the healing of a long vacancy suggest the intimate connection between vacancies and topological defects that may provide an extra dimension in the engineering of defects in extensive crystalline materials for desired properties. We thank the financial support from the U.S. Department of Commerce, National Institute of Standards and Technology, the Office of the Director of Defense Research and Engineering (DDR&E) and the Air Force Office of Scientific Research.

  18. Rheumatic fever: update on the Jones criteria according to the American Heart Association review - 2015.

    PubMed

    Pereira, Breno Álvares de Faria; Belo, Alinne Rodrigues; Silva, Nilzio Antônio da

    Rheumatic fever is still currently a prevalent disease, especially in developing countries. Triggered by a Group A β-hemolytic Streptococcus infection, the disease may affect genetically predisposed patients. Rheumatic carditis is the most important of its clinical manifestations, which can generate incapacitating sequelae of great impact for the individual and for society. Currently, its diagnosis is made based on the Jones criteria, established in 1992 by the American Heart Association. In 2015, the AHA carried out a significant review of these criteria, with new diagnostic parameters and recommendations. In the present study, the authors perform a critical analysis of this new review, emphasizing the most relevant points for clinical practice. Copyright © 2017. Published by Elsevier Editora Ltda.

  19. Rheumatic fever: update on the Jones criteria according to the American Heart Association review - 2015.

    PubMed

    Pereira, Breno Álvares de Faria; Belo, Alinne Rodrigues; Silva, Nilzio Antônio da

    2017-03-06

    Rheumatic fever is still currently a prevalent disease, especially in developing countries. Triggered by a Group A β-hemolytic Streptococcus infection, the disease may affect genetically predisposed patients. Rheumatic carditis is the most important of its clinical manifestations, which can generate incapacitating sequelae of great impact for the individual and for society. Currently, its diagnosis is made based on the Jones Criteria, established in 1992 by the American Heart Association (AHA). In 2015, the AHA carried out a significant review of these criteria, with new diagnostic parameters and recommendations. In the present study, the authors perform a critical analysis of this new review, emphasizing the most relevant points for clinical practice. Copyright © 2017. Published by Elsevier Editora Ltda.

  20. Properties of the Lennard-Jones dimeric fluid in two dimensions: An integral equation study

    SciTech Connect

    Urbic, Tomaz; Dias, Cristiano L.

    2014-03-07

    The thermodynamic and structural properties of the planar soft-sites dumbbell fluid are examined by Monte Carlo simulations and integral equation theory. The dimers are built of two Lennard-Jones segments. Site-site integral equation theory in two dimensions is used to calculate the site-site radial distribution functions for a range of elongations and densities and the results are compared with Monte Carlo simulations. The critical parameters for selected types of dimers were also estimated. We analyze the influence of the bond length on critical point as well as tested correctness of site-site integral equation theory with different closures. The integral equations can be used to predict the phase diagram of dimers whose molecular parameters are known.

  1. The Lion and the Lady Revisited: Another Look at the Firing of Mary L. Jones as Los Angeles Public Librarian in 1905.

    ERIC Educational Resources Information Center

    Wiegand, Wayne A.

    1983-01-01

    Recounts events that led to the firing of Mary L. Jones, Director of Los Angeles Public Library (1905) and caught in public crossfire such figures as the mayor, city council, library board of directors, Charles Lummis (Jones's replacement), Susan B. Anthony, Anna Shaw, Herbert Putnam, and Melvil Dewey. (29 references) (EJS)

  2. Combining smart darting with parallel tempering using Eckart space: Application to Lennard-Jones clusters

    NASA Astrophysics Data System (ADS)

    Nigra, Pablo; Freeman, David L.; Doll, J. D.

    2005-03-01

    The smart-darting algorithm is a Monte Carlo based simulation method used to overcome quasiergodicity problems associated with disconnected regions of configurations space separated by high energy barriers. As originally implemented, the smart-darting method works well for clusters at low temperatures with the angular momentum restricted to zero and where there are no transitions to permutational isomers. If the rotational motion of the clusters is unrestricted or if permutational isomerization becomes important, the acceptance probability of darting moves in the original implementation of the method becomes vanishingly small. In this work the smart-darting algorithm is combined with the parallel tempering method in a manner where both rotational motion and permutational isomerization events are important. To enable the combination of parallel tempering with smart darting so that the smart-darting moves have a reasonable acceptance probability, the original algorithm is modified by using a restricted space for the smart-darting moves. The restricted space uses a body-fixed coordinate system first introduced by Eckart, and moves in this Eckart space are coupled with local moves in the full 3N-dimensional space. The modified smart-darting method is applied to the calculation of the heat capacity of a seven-atom Lennard-Jones cluster. The smart-darting moves yield significant improvement in the statistical fluctuations of the calculated heat capacity in the region of temperatures where the system isomerizes. When the modified smart-darting algorithm is combined with parallel tempering, the statistical fluctuations of the heat capacity of a seven-atom Lennard-Jones cluster using the combined method are smaller than parallel tempering when used alone.

  3. Structural behavior and self-assembly of Lennard-Jones clusters on rigid surfaces.

    PubMed

    Paci, Irina; Szleifer, Igal; Ratner, Mark A

    2005-07-07

    The phase behavior and surface pattern formation for intermediate size Lennard-Jones clusters on rigid surfaces are examined. We use a parallel tempering Monte Carlo algorithm, in the canonical ensemble. Tempering is done over the temperature domain in most of the calculations. A two-dimensional temperature and Hamiltonian tempering algorithm is also implemented, to examine its usefulness in investigating this type of problem. In general, we observe gas phase systems as they undergo a condensation transition on the surface, followed by a freezing transition. The final solid state pattern formed by the cluster on the surface is the result of a number of competing effects. First, there is a competition between attraction within the cluster and that between cluster and surface atoms. Second, a monolayer of Lennard-Jones atoms tends to pack in a hexadic geometry. This geometry is frustrated on a surface with a different symmetry. The molecular organization of the substrate has a serious impact on the cluster packing. The surface morphology and the size mismatch between cluster and surface atoms, along with the relative interaction strengths, determine which of the effects prevail. When the surface atoms are small enough, the interactions within the cluster determine the symmetry of the pattern. In such a case, the substrate behaves similarly to a continuous surface, and the low-temperature pattern is a hexadic monolayer. When the sizes of the surface and cluster atoms are comparable, the low-temperature adsorbed geometry mimics the substrate symmetry. On a face-centered cubic surface, face-centered cubic monolayers or droplets are obtained.

  4. Population inversion of binary Lennard-Jones mixtures in nanoslit pores (a density functional theory study).

    PubMed

    Taghizadeh, Ameneh; Keshavarzi, Ezat Tahmineh

    2011-04-07

    The aim of this work is to investigate the population inversion of binary asymmetric Lennard-Jones mixtures inside nanoslit pores due to confinement effects for both vapor and liquid phases. For this purpose we have used mean field fundamental measure theory, and the effect of different parameters such as interaction strength and size ratios of the components, confinement size, and thermodynamic state on the population distribution of molecules have been studied. It has been shown that in the case of bulk liquid mixtures, increasing the role of confinement effects can lead to preferential adsorption of the component with larger size and weaker intermolecular interactions into the nanopore in spite of its minority in the bulk which is referred as population inversion. This population inversion phenomenon is terminated by a sudden condensation which, interestingly, involves a simultaneous adsorption and desorption for more and less bulk concentrated species, respectively. We have demonstrated that this condensation phenomenon shifts to higher bulk densities with increasing the role of confinement effects such that in some cases population inversion is observable for the whole range of densities. In consideration of the conditions in which vapor Lennard-Jones mixtures undergo capillary condensation, the population distribution of components in the vapor- and liquidlike phases was studied. It has been shown that variation of parameters such as interaction strength and size ratios, temperature, and confinement size can lead to conditions in which capillary condensation is accompanying with a population inversion phenomenon. In these cases, whereas the composition of vaporlike phases is the same as bulk fluid, liquidlike phases are richer in the component with less bulk concentration.

  5. Correction of clawed hallux deformity: comparison of the Jones procedure and FHL transfer in a cadaver model.

    PubMed

    Elias, Fady N; Yuen, Tracy J; Olson, Soren L; Sangeorzan, Bruce J; Ledoux, William R

    2007-03-01

    A clawed hallux is defined as extension of the first metatarsophalangeal (MTP) joint combined with flexion of the interphalangeal (IP) joint. Two operative procedures, the modified Jones procedure and flexor hallucis longus (FHL) transfer, are indicated for correction. The purpose of this study were to evaluate the overall effectiveness of these two procedures in correcting both the clawed hallux deformity and its mechanical consequences and to compare their effect on postoperative plantar pressures. The modified Jones procedure and FHL transfer were done on cadaver specimens that were tested before and after surgery in a specialized foot-loading frame. We quantified the angular correction of the MTP and the IP joints, as well as the plantar pressures under the head of the first metatarsal and the hallux. Both surgeries were equally effective in correcting the angular deformity at the MTP and IP joints (p = 0.037 and 0.0020, respectively). A significant reduction in the plantar pressure (p = 0.015) beneath the first metatarsal was observed with both the modified Jones procedure and the FHL transfer. Overall, there was no significant difference between preoperative and postoperative pressures beneath the hallux (p = 0.5); however, for the FHL overpull group there was significantly less pressure beneath the hallux after surgery (p = 0.014). The two surgeries produced similar results, but the FHL transfer does not require fusion of the hallux, which is considered an undesirable co-morbidity of the modified Jones procedure.

  6. Comment on Cross, Fine, Jones, and Walsh (2012): Good Therapeutic Services--Therapeutic Advocacy and Forensic Neutrality

    ERIC Educational Resources Information Center

    Connell, Mary

    2012-01-01

    Cross, Fine, Jones, and Walsh (2012) provided a thoughtful review and critique of a book chapter describing the interview process at Child Advocacy Centers. They observed some of the ways that concerns raised in that chapter are being addressed and described revised guidelines that further clarify issues. Ongoing research and examination of the…

  7. Comment on Cross, Fine, Jones, and Walsh (2012): Good Therapeutic Services--Therapeutic Advocacy and Forensic Neutrality

    ERIC Educational Resources Information Center

    Connell, Mary

    2012-01-01

    Cross, Fine, Jones, and Walsh (2012) provided a thoughtful review and critique of a book chapter describing the interview process at Child Advocacy Centers. They observed some of the ways that concerns raised in that chapter are being addressed and described revised guidelines that further clarify issues. Ongoing research and examination of the…

  8. Thermodynamic properties of supercritical n-m Lennard-Jones fluids and isochoric and isobaric heat capacity maxima and minima

    NASA Astrophysics Data System (ADS)

    Mairhofer, Jonas; Sadus, Richard J.

    2013-10-01

    Molecular dynamics simulations are reported for the thermodynamic properties of n-m Lennard-Jones fluids, where n = 10 and 12, and m = 5 and 6. Results are reported for the thermal expansion coefficient, isothermal and adiabatic compressibilities, isobaric and isochoric heat capacities, Joule-Thomson coefficient, and speed of sound at supercritical conditions covering a wide range of fluid densities. The thermodynamic criteria for maxima/minima in the isochoric and isobaric heat capacities are identified and the simulation results are also compared with calculations from Lennard-Jones equations of state. The Johnson et al. [Mol. Phys. 78, 591 (1993)] equation of state can be used to reproduce all heat capacity phenomena reported [T. M. Yigzawe and R. J. Sadus, J. Chem. Phys. 138, 194502 (2013)] from molecular dynamics simulations for the 12-6 Lennard-Jones potential. Significantly, these calculations and molecular dynamics results for other n-m Lennard-Jones potentials support the existence of Cp minima at supercritical conditions. The values of n and m also have a significant influence on many other thermodynamic properties.

  9. INVESTIGATION OF EXPLOSIVE PARAMETERS USING A MODIFIED LENNARD-JONES-DEVONSHIRE THREE-SHELL POTENTIAL EQUATION OF STATE,

    DTIC Science & Technology

    of state . Calcu lations are made of various pressures of equilibrium products from detonation of RDX. (Author)...priori estimate of the system parameters. It is an extension of the work on the three-shell modification of the Lennard Jones - Devonshire equation

  10. Thermodynamic properties of supercritical n-m Lennard-Jones fluids and isochoric and isobaric heat capacity maxima and minima.

    PubMed

    Mairhofer, Jonas; Sadus, Richard J

    2013-10-21

    Molecular dynamics simulations are reported for the thermodynamic properties of n-m Lennard-Jones fluids, where n = 10 and 12, and m = 5 and 6. Results are reported for the thermal expansion coefficient, isothermal and adiabatic compressibilities, isobaric and isochoric heat capacities, Joule-Thomson coefficient, and speed of sound at supercritical conditions covering a wide range of fluid densities. The thermodynamic criteria for maxima∕minima in the isochoric and isobaric heat capacities are identified and the simulation results are also compared with calculations from Lennard-Jones equations of state. The Johnson et al. [Mol. Phys. 78, 591 (1993)] equation of state can be used to reproduce all heat capacity phenomena reported [T. M. Yigzawe and R. J. Sadus, J. Chem. Phys. 138, 194502 (2013)] from molecular dynamics simulations for the 12-6 Lennard-Jones potential. Significantly, these calculations and molecular dynamics results for other n-m Lennard-Jones potentials support the existence of Cp minima at supercritical conditions. The values of n and m also have a significant influence on many other thermodynamic properties.

  11. Limitations of the Motivational Intensity Model of Attentional Tuning: Reply to Harmon-Jones, Gable, and Price (2011)

    ERIC Educational Resources Information Center

    Friedman, Ronald S.; Forster, Jens

    2011-01-01

    In an integrative review, we concluded that implicit affective cues--rudimentary stimuli associated with the onset of arousing positive or negative emotional states and/or with appraisals that the environment is benign or threatening--automatically moderate the scope of attention (Friedman & Forster, 2010). In their comment, Harmon-Jones, Gable,…

  12. Statement of Facts for 1992 City-Wide Mock Trial Competitions. United States v. David Jones. MT-92.

    ERIC Educational Resources Information Center

    National Inst. for Citizen Education in the Law, Washington, DC.

    Prepared by the District of Columbia Street Law Project for its 21 annual city-wide mock trial competition, this instructional handout provides material for a mock rape trial. David Jones and Susan Williams, both students at Capital University, had dated on and off during the previous years and on the night of the incident had attended a party…

  13. Conceptual, Methodological, and Empirical Ambiguities in the Linkage between Anger and Approach: Comment on Carver and Harmon-Jones (2009)

    ERIC Educational Resources Information Center

    Tomarken, Andrew J.; Zald, David H.

    2009-01-01

    C. S. Carver and E. Harmon-Jones have made an important contribution to the understanding of anger, its linkage to higher order dimensions of emotion, and potential neurobiological substrates. The authors believe, however, that their model and future research conducted to test it would be improved by a more precise explication and parsing of the…

  14. Elizabeth Jones Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

    ERIC Educational Resources Information Center

    Smith, Valinda C.

    This final performance report for the Elizabeth Jones Library literacy project begins with a section that provides quantitative data. The next section compares actual accomplishments to the following project goals and related objectives for fiscal year 1992: (1) to provide a versatile workplace literacy program useful to any business in the…

  15. Determination of the Melting Curve of the Modified Lennard-Jones System Using the Nonequilibrium Relaxation Method

    NASA Astrophysics Data System (ADS)

    Asano, Yuta; Fuchizaki, Kazuhiro

    2017-02-01

    The melting curve of the modified Lennard-Jones system, which has been obtained by equating the free energies between the solid and liquid phases, was reinvestigated using the nonequilibrium relaxation method. The latter method satisfactorily reproduced the previous result with much simplified procedures.

  16. Life on the edge in eastern Alaska: Basal Ordovician(Tremadocian), platform-margin faunas of the Jones Ridge Formation

    USGS Publications Warehouse

    Taylor, J. F.; Allen, T. J.; Repetski, John E.; Strauss, J. V.; Irwin, S. J.

    2015-01-01

    As the most fossiliferous and least deformed succession of unequivocally Laurentian lower Paleozoic strata in Alaska, the Jones Ridge Limestone has provided critical data for numerous stratigraphic studies (e. g. Palmer 1968; Harris et al. 1995; Dumoulin et al. 2002; Dumoulin and Harris 2012) focused on the Cambrian and Ordovician of northwestern North America/northeastern Laurentia (Figure 1). The Jones Ridge faunas are also significant in having provided the type material for some of the widespread and biostratigraphically useful latest Furongian and (perhaps) earliest Tremadocian species described by Kobayashi (1936) and Palmer (1968). Unfortunately, some of those taxa were based on very limited material for which, in the earlier study in particular, no detailed information regarding locality or stratigraphic horizon was provided. The limited amount of information and material available for study from Jones Ridge results largely from its remote location on the Yukon-Alaska boundary approximately 25km north of Eagle, Alaska, which renders it accessible only by helicopter. Parts of three field seasons (2010, 2011, and 2014) were invested in re-description and intensive sampling of the type section of the Jones Ridge Formation in order to produce an integrated and greatly refined set of biostratigraphic, chemostratigraphic, and sedimentological data. The new data support the interpretation offered by Palmer (1968) of the Jones Ridge strata as the product of deposition in outermost platform to upper slope environments offered by Palmer (1968) on the basis of taxonomic content of the faunas and close proximity of deep water units of equivalent age a very short distance to the southwest.

  17. Excess entropy and crystallization in Stillinger-Weber and Lennard-Jones fluids

    SciTech Connect

    Dhabal, Debdas; Chakravarty, Charusita; Nguyen, Andrew Huy; Molinero, Valeria; Singh, Murari; Khatua, Prabir; Bandyopadhyay, Sanjoy

    2015-10-28

    Molecular dynamics simulations are used to contrast the supercooling and crystallization behaviour of monatomic liquids that exemplify the transition from simple to anomalous, tetrahedral liquids. As examples of simple fluids, we use the Lennard-Jones (LJ) liquid and a pair-dominated Stillinger-Weber liquid (SW{sub 16}). As examples of tetrahedral, water-like fluids, we use the Stillinger-Weber model with variable tetrahedrality parameterized for germanium (SW{sub 20}), silicon (SW{sub 21}), and water (SW{sub 23.15} or mW model). The thermodynamic response functions show clear qualitative differences between simple and water-like liquids. For simple liquids, the compressibility and the heat capacity remain small on isobaric cooling. The tetrahedral liquids in contrast show a very sharp rise in these two response functions as the lower limit of liquid-phase stability is reached. While the thermal expansivity decreases with temperature but never crosses zero in simple liquids, in all three tetrahedral liquids at the studied pressure, there is a temperature of maximum density below which thermal expansivity is negative. In contrast to the thermodynamic response functions, the excess entropy on isobaric cooling does not show qualitatively different features for simple and water-like liquids; however, the slope and curvature of the entropy-temperature plots reflect the heat capacity trends. Two trajectory-based computational estimation methods for the entropy and the heat capacity are compared for possible structural insights into supercooling, with the entropy obtained from thermodynamic integration. The two-phase thermodynamic estimator for the excess entropy proves to be fairly accurate in comparison to the excess entropy values obtained by thermodynamic integration, for all five Lennard-Jones and Stillinger-Weber liquids. The entropy estimator based on the multiparticle correlation expansion that accounts for both pair and triplet correlations, denoted by S{sub trip

  18. Epibenthic assemblages in the Celtic Sea and associated with the Jones Bank

    NASA Astrophysics Data System (ADS)

    Ellis, J. R.; Martinez, I.; Burt, G. J.; Scott, B. E.

    2013-10-01

    The epibenthic assemblages in the Celtic Sea are described from the catches from 2 m beam trawl surveys undertaken from 2000 to 2009. During this period 154 samples were collected. The most ubiquitous species in the study area were the natantid shrimps Processa spp. and Crangon allmanni, the hermit crabs Pagurus prideaux and Anapagurus laevis, sand star Astropecten irregularis and spotted dragonet Callionymus maculatus. Multivariate community analyses indicated that catches (numbers per tow) were distributed across six assemblages, two of which were predominant in the study area. Most catches were attributed to either a 'shelf edge assemblage', which was widespread in deeper waters (114-423 m water depth) or an 'outer shelf assemblage' that occurred across much of the Celtic Sea north of 49°N in waters 49-175 m deep. The dominant species along the edge of the continental shelf were the hormathid anemome Actinauge richardi, sea spider Pycnogonum littorale (which associated with A. richardi), Devonshire cup coral Caryophyllia smithii and the swimming crab Macropipus tuberculatus. The dominant species in the outer shelf assemblage included P. prideaux, C. allmanni, A. laevis and common starfish Asterias rubens. Stations closer to shore were relatively distinct and catches in this 'inner shelf assemblage' were composed primarily of an inshore fauna (e.g. Ophiura ophiura, C. allmanni and Liocarcinus holsatus). Stations in the southern part of the survey grid were also relatively distinct ('southern Celtic Sea assemblage'), and several large echinoderms (Porania pulvillus, Stichastrella rosea and Anseropoda placenta) dominated at these sites. Three of the deepest stations were also relatively distinct, as were a group of stations in the muddy habitat of the Celtic Deep and comparable grounds elsewhere in the region, where Nucula sulcata and Alpheus glaber were characteristic. Catches on the shallower parts of the Jones Bank (and on another bank in the region) were

  19. Excess entropy and crystallization in Stillinger-Weber and Lennard-Jones fluids

    NASA Astrophysics Data System (ADS)

    Dhabal, Debdas; Nguyen, Andrew Huy; Singh, Murari; Khatua, Prabir; Molinero, Valeria; Bandyopadhyay, Sanjoy; Chakravarty, Charusita

    2015-10-01

    Molecular dynamics simulations are used to contrast the supercooling and crystallization behaviour of monatomic liquids that exemplify the transition from simple to anomalous, tetrahedral liquids. As examples of simple fluids, we use the Lennard-Jones (LJ) liquid and a pair-dominated Stillinger-Weber liquid (SW16). As examples of tetrahedral, water-like fluids, we use the Stillinger-Weber model with variable tetrahedrality parameterized for germanium (SW20), silicon (SW21), and water (SW23.15 or mW model). The thermodynamic response functions show clear qualitative differences between simple and water-like liquids. For simple liquids, the compressibility and the heat capacity remain small on isobaric cooling. The tetrahedral liquids in contrast show a very sharp rise in these two response functions as the lower limit of liquid-phase stability is reached. While the thermal expansivity decreases with temperature but never crosses zero in simple liquids, in all three tetrahedral liquids at the studied pressure, there is a temperature of maximum density below which thermal expansivity is negative. In contrast to the thermodynamic response functions, the excess entropy on isobaric cooling does not show qualitatively different features for simple and water-like liquids; however, the slope and curvature of the entropy-temperature plots reflect the heat capacity trends. Two trajectory-based computational estimation methods for the entropy and the heat capacity are compared for possible structural insights into supercooling, with the entropy obtained from thermodynamic integration. The two-phase thermodynamic estimator for the excess entropy proves to be fairly accurate in comparison to the excess entropy values obtained by thermodynamic integration, for all five Lennard-Jones and Stillinger-Weber liquids. The entropy estimator based on the multiparticle correlation expansion that accounts for both pair and triplet correlations, denoted by Strip, is also studied. Strip is a

  20. Excess entropy and crystallization in Stillinger-Weber and Lennard-Jones fluids.

    PubMed

    Dhabal, Debdas; Nguyen, Andrew Huy; Singh, Murari; Khatua, Prabir; Molinero, Valeria; Bandyopadhyay, Sanjoy; Chakravarty, Charusita

    2015-10-28

    Molecular dynamics simulations are used to contrast the supercooling and crystallization behaviour of monatomic liquids that exemplify the transition from simple to anomalous, tetrahedral liquids. As examples of simple fluids, we use the Lennard-Jones (LJ) liquid and a pair-dominated Stillinger-Weber liquid (SW16). As examples of tetrahedral, water-like fluids, we use the Stillinger-Weber model with variable tetrahedrality parameterized for germanium (SW20), silicon (SW21), and water (SW(23.15) or mW model). The thermodynamic response functions show clear qualitative differences between simple and water-like liquids. For simple liquids, the compressibility and the heat capacity remain small on isobaric cooling. The tetrahedral liquids in contrast show a very sharp rise in these two response functions as the lower limit of liquid-phase stability is reached. While the thermal expansivity decreases with temperature but never crosses zero in simple liquids, in all three tetrahedral liquids at the studied pressure, there is a temperature of maximum density below which thermal expansivity is negative. In contrast to the thermodynamic response functions, the excess entropy on isobaric cooling does not show qualitatively different features for simple and water-like liquids; however, the slope and curvature of the entropy-temperature plots reflect the heat capacity trends. Two trajectory-based computational estimation methods for the entropy and the heat capacity are compared for possible structural insights into supercooling, with the entropy obtained from thermodynamic integration. The two-phase thermodynamic estimator for the excess entropy proves to be fairly accurate in comparison to the excess entropy values obtained by thermodynamic integration, for all five Lennard-Jones and Stillinger-Weber liquids. The entropy estimator based on the multiparticle correlation expansion that accounts for both pair and triplet correlations, denoted by S(trip), is also studied. S

  1. A Jones matrix formalism for simulating three-dimensional polarized light imaging of brain tissue

    PubMed Central

    Menzel, M.; Michielsen, K.; De Raedt, H.; Reckfort, J.; Amunts, K.; Axer, M.

    2015-01-01

    The neuroimaging technique three-dimensional polarized light imaging (3D-PLI) provides a high-resolution reconstruction of nerve fibres in human post-mortem brains. The orientations of the fibres are derived from birefringence measurements of histological brain sections assuming that the nerve fibres—consisting of an axon and a surrounding myelin sheath—are uniaxial birefringent and that the measured optic axis is oriented in the direction of the nerve fibres (macroscopic model). Although experimental studies support this assumption, the molecular structure of the myelin sheath suggests that the birefringence of a nerve fibre can be described more precisely by multiple optic axes oriented radially around the fibre axis (microscopic model). In this paper, we compare the use of the macroscopic and the microscopic model for simulating 3D-PLI by means of the Jones matrix formalism. The simulations show that the macroscopic model ensures a reliable estimation of the fibre orientations as long as the polarimeter does not resolve structures smaller than the diameter of single fibres. In the case of fibre bundles, polarimeters with even higher resolutions can be used without losing reliability. When taking the myelin density into account, the derived fibre orientations are considerably improved. PMID:26446561

  2. Determination of anharmonic free energy contributions: Low temperature phases of the Lennard-Jones system

    DOE PAGES

    Calero, C.; Knorowski, C.; Travesset, A.

    2016-03-22

    We investigate a general method to calculate the free energy of crystalline solids by considering the harmonic approximation and quasistatically switching the anharmonic contribution. The advantage of this method is that the harmonic approximation provides an already very accurate estimate of the free energy, and therefore the anharmonic term is numerically very small and can be determined to high accuracy. We further show that the anharmonic contribution to the free energy satisfies a number of exact inequalities that place constraints on its magnitude and allows approximate but fast and accurate estimates. The method is implemented into a readily available generalmore » software by combining the code HOODLT (Highly Optimized Object Oriented Dynamic Lattice Theory) for the harmonic part and the molecular dynamics (MD) simulation package HOOMD-blue for the anharmonic part. We use the method to calculate the low temperature phase diagram for Lennard-Jones particles. We demonstrate that hcp is the equilibrium phase at low temperature and pressure and obtain the coexistence curve with the fcc phase, which exhibits reentrant behavior. Furthermore, several implications of the method are discussed.« less

  3. Supercooled Lennard-Jones liquids and glasses: a kinetic Monte Carlo approach*1

    NASA Astrophysics Data System (ADS)

    Hernández-Rojas, Javier; Wales, David J.

    2004-05-01

    A kinetic Monte Carlo (KMC) method is used to study the structural properties and dynamics of a supercooled binary Lennard-Jones liquid around the glass transition temperature. This technique permits us to explore the potential energy surface and barrier distributions without suffering the exponential slowing down at low temperature that affects molecular dynamics simulations. In agreement with previous studies we observe a distinct change in behaviour around $T=0.45$, close to the dynamical transition temperature $T_c$ of mode coupling theory (MCT). Below this temperature the number of different local minima visited by the system for the same number of KMC steps decreases by more than an order of magnitude. The mean number of atoms involved in each jump between local minima and the average distance they move also decreases significantly, and new features appear in the partial structure factor. Above $T~0.45$ the probability distribution for the magnitude of the atomic displacement per KMC step exhibits an exponential decay, which is only weakly temperature dependent.

  4. Local structures in a computer-generated liquid. Two-dimensional Lennard-Jones liquid

    NASA Astrophysics Data System (ADS)

    Mitus, Antoni C.; Patashinskii, Alexander Z.; Sokolowski, Stefan

    1991-06-01

    We study the local structures in a 2D Lennard-Jones liquid of 2500 atoms near the melting line ( ϱ ∗ = 0.76 , T ∗ = 0.47 ) with the help of methods of mathematical statistics based on an earlier proposed probabilistic approach. We analyze the local structures in individual configurations and study the time evolution of patterns of matter which is close to the solid hexagonal structure. We conclude that the model liquid displays two types of local structure: hexagonal and “chaotic”. The first one corresponds to the fluctuations of the hexagon with root-mean-square fluctuations ξ of atoms equal to ξ = 0.14-0.16 while the second one can be represented by a strongly fluctuating (ξ = 0.25-0.30) “defect” pattern. We discuss the consequences of the physical picture of the liquid as a locally ordered two-structure system for the methodology of computer simulations and for theories of the 2D liquid phase.

  5. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images.

    PubMed

    Xu, Yongzheng; Yu, Guizhen; Wang, Yunpeng; Wu, Xinkai; Ma, Yalong

    2016-08-19

    A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J) and linear SVM classifier with HOG feature (HOG + SVM) methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV) images. As both V-J and HOG + SVM are sensitive to on-road vehicles' in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians.

  6. Optimization of magneto-optical Kerr setup: analyzing experimental assemblies using Jones matrix formalism.

    PubMed

    Polisetty, S; Scheffler, J; Sahoo, S; Wang, Yi; Mukherjee, T; He, Xi; Binek, Ch

    2008-05-01

    We present a comparative study on an experimental and theoretical optimization of magneto-optical Kerr setups based on photoelastic modulation and phase sensitive detector methodology. The first and second harmonics, I omega,2 omega, of the reflected light intensity are measured for a CoO/Co magnetic reference film. The magnetic field dependence of the optical off-diagonal Fresnel reflection coefficients rps and rsp follows the sample magnetization. Different Kerr setups provide various dependencies of I omega,2 omega on the reflection coefficients and, hence, on the Kerr ellipticity epsilon K and rotation theta K. Jones matrix formalism has been used to analyze the impact of a systematic variation of relative analyzer and polarizer orientations with respect to each other and with respect to the retardation axis of the modulator involved in longitudinal Kerr setups for incoming s-polarized light. We find one particular setup which maximizes I(omega) as well as I2 omega and maximizes the signal-to-noise ratio. Inefficient setups are characterized by I omega,2 omega intensities involving large nonmagnetic contributions of rp and rs.

  7. A Jones matrix formalism for simulating three-dimensional polarized light imaging of brain tissue.

    PubMed

    Menzel, M; Michielsen, K; De Raedt, H; Reckfort, J; Amunts, K; Axer, M

    2015-10-06

    The neuroimaging technique three-dimensional polarized light imaging (3D-PLI) provides a high-resolution reconstruction of nerve fibres in human post-mortem brains. The orientations of the fibres are derived from birefringence measurements of histological brain sections assuming that the nerve fibres—consisting of an axon and a surrounding myelin sheath—are uniaxial birefringent and that the measured optic axis is oriented in the direction of the nerve fibres (macroscopic model). Although experimental studies support this assumption, the molecular structure of the myelin sheath suggests that the birefringence of a nerve fibre can be described more precisely by multiple optic axes oriented radially around the fibre axis (microscopic model). In this paper, we compare the use of the macroscopic and the microscopic model for simulating 3D-PLI by means of the Jones matrix formalism. The simulations show that the macroscopic model ensures a reliable estimation of the fibre orientations as long as the polarimeter does not resolve structures smaller than the diameter of single fibres. In the case of fibre bundles, polarimeters with even higher resolutions can be used without losing reliability. When taking the myelin density into account, the derived fibre orientations are considerably improved.

  8. Nucleation of liquid droplets and voids in a stretched Lennard-Jones fcc crystal

    SciTech Connect

    Baidakov, Vladimir G. Tipeev, Azat O.

    2015-09-28

    The method of molecular dynamics simulation has been used to investigate the phase decay of a metastable Lennard-Jones face-centered cubic crystal at positive and negative pressures. It is shown that at high degrees of metastability, crystal decay proceeds through the spontaneous formation and growth of new-phase nuclei. It has been found that there exists a certain boundary temperature. Below this temperature, the crystal phase disintegrates as the result of formation of voids, and above, as a result of formation of liquid droplets. The boundary temperature corresponds to the temperature of cessation of a crystal–liquid phase equilibrium when the melting line comes in contact with the spinodal of the stretched liquid. The results of the simulations are interpreted in the framework of classical nucleation theory. The thermodynamics of phase transitions in solids has been examined with allowance for the elastic energy of stresses arising owing to the difference in the densities of the initial and the forming phases. As a result of the action of elastic forces, at negative pressures, the boundary of the limiting superheating (stretching) of a crystal approaches the spinodal, on which the isothermal bulk modulus of dilatation becomes equal to zero. At the boundary of the limiting superheating (stretching), the shape of liquid droplets and voids is close to the spherical one.

  9. Determination of anharmonic free energy contributions: Low temperature phases of the Lennard-Jones system

    SciTech Connect

    Calero, C.; Knorowski, C.; Travesset, A.

    2016-03-22

    We investigate a general method to calculate the free energy of crystalline solids by considering the harmonic approximation and quasistatically switching the anharmonic contribution. The advantage of this method is that the harmonic approximation provides an already very accurate estimate of the free energy, and therefore the anharmonic term is numerically very small and can be determined to high accuracy. We further show that the anharmonic contribution to the free energy satisfies a number of exact inequalities that place constraints on its magnitude and allows approximate but fast and accurate estimates. The method is implemented into a readily available general software by combining the code HOODLT (Highly Optimized Object Oriented Dynamic Lattice Theory) for the harmonic part and the molecular dynamics (MD) simulation package HOOMD-blue for the anharmonic part. We use the method to calculate the low temperature phase diagram for Lennard-Jones particles. We demonstrate that hcp is the equilibrium phase at low temperature and pressure and obtain the coexistence curve with the fcc phase, which exhibits reentrant behavior. Furthermore, several implications of the method are discussed.

  10. "Familiarity-based stimulus generalization of conditioned suppression": Correction to Robinson, Whitt, and Jones (2017).

    PubMed

    2017-07-01

    Reports an error in "Familiarity-based stimulus generalization of conditioned suppression" by Jasper Robinson, Emma J. Whitt and Peter M. Jones (Journal of Experimental Psychology: Animal Learning and Cognition, 2017[Apr], Vol 43[2], 159-170). The article was incorrectly published under American Psychological Association copyright. The authors should have retained copyright of this article under the Creative Commons Attribution License. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2017-15338-002.) We report that stimulus novelty/familiarity is able to modulate stimulus generalization and discuss the theoretical implications of novelty/familiarity coding. Rats in Skinner boxes received clicker → shock pairings before generalization testing to a tone. Before clicker training, different groups of rats received preexposure treatments designed to systematically modulate the clicker and the tone's novelty and familiarity. Rats whose preexposure matched novelty/familiarity (i.e., either both or neither clicker and tone were preexposed) showed enhanced suppression to the tone relative to rats whose preexposure mixed novelty/familiarity (i.e., only clicker or tone was preexposed). This was not the result of sensory preconditioning to clicker and tone. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  11. Selected hydrogeologic and water-quality data from Jones Beach Island, Long Island, New York

    USGS Publications Warehouse

    Scorca, M.P.; Reilly, T.E.; Franke, O.L.

    1995-01-01

    A data-collection site was instrumented on Jones Beach Island, a barrier island south of Long Island, N.Y., to study local freshwater/ saltwater relations in the shallow ground-water system. A geologic test boring revealed about 88 feet of well-sorted glacial outwash sand above about 15 feet of Gardiners Clay, which directly overlies silty sand of the Magothy Formation. Tidal effects on water levels in Great South Bay, the upper glacial aquifer, and the Magothy aquifer were observed and quantified with a tidal gage in the bay and analog water-level recorders in the wells.Chloride concentrations in the upper Magothy aquifer were higher than expected--about 270 mg/L (milligrams per liter), and those in the upper glacial aquifer were 17,000 to 19,000 mg/L, about the same as in Great South Bay. Estimates of pressure and freshwater equivalent heads indicate that, at the data-collection site, freshwater is discharging upward from the Magothy aquifer into the salty upper glacial aquifer, but dilution by this freshwater is undetectable. The reason for the elevated chloride concentration in the Magothy aquifer cannot be determined from available hydrogeologic information.

  12. Calorimetric markers of Bence Jones and nonsecretory multiple myeloma serum proteome.

    PubMed

    Todinova, Svetla; Krumova, Sashka; Radoeva, Ralitsa; Gartcheva, Lidia; Taneva, Stefka G

    2014-12-16

    The present work provides a thermodynamic description of blood serum from patients diagnosed with Bence Jones myeloma (BJMM) and nonsecretory myeloma (NSMM) by means of differential scanning calorimetry (DSC), serum protein electrophoresis, and free light chain assay. Specific alterations in the thermodynamic behavior of both BJMM and NSMM proteome have been revealed. On the basis of the transition temperature of the main transition in the calorimetric profiles and the shape similarity criterion, we defined BJMM and NSMM sets/subsets of thermograms with very similar thermodynamic features. We show that some of the BJMM and NSMM subsets correlate with previously defined secretory myeloma subsets (Todinova et al. Anal. Chem. 2011, 83, 7992). The established analogies strongly suggest that common molecular markers contribute to the calorimetric profiles of the different, secretory and nonsecretory, myeloma types; our data show robust evidence that these are ligands stabilizing the major serum proteins. We demonstrate that the DSC approach might be highly beneficial, especially for NSMM patients, since the characteristic modifications in the DSC profiles might serve as calorimetric markers when no monoclonal proteins can be detected in the bloodstream and the diagnosis heavily relies on invasive methods.

  13. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images

    PubMed Central

    Xu, Yongzheng; Yu, Guizhen; Wang, Yunpeng; Wu, Xinkai; Ma, Yalong

    2016-01-01

    A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J) and linear SVM classifier with HOG feature (HOG + SVM) methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV) images. As both V-J and HOG + SVM are sensitive to on-road vehicles’ in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians. PMID:27548179

  14. High Precision Calculations of the Lennard-Jones Lattice Constants for Five Lattices

    NASA Astrophysics Data System (ADS)

    Stein, Matthew

    2017-01-01

    The total potential energy of a crystal as described by the Lennard-Jones (L-J) potential depends in part upon the calculation of lattice constants. Knowing these constants to high precision is useful for prediction of the lattice type and simulation of crystals such as rare-gas solids or germanium detectors, but reaching higher precision is computationally costly and challenging. Presented here is the extension of the precision of the lattice constants, Lp, up to 32 decimal digits, and in some cases corrections from previous publication. The Lp terms are given for 4 <= p <= 30 in the simple cubic, face-centered cubic, body-centered cubic, hexagonal-close-pack, and diamond lattices. This precision was obtained through the use of careful parallelization technique, exploitation of the symmetries of each lattice, and the ``onionization'' of the simulated crystal. The results of this computation, along with the tools and algorithm strategies to make this computation possible, are explained in detail graphically.

  15. Weighted density-functional theory for simple fluids: Prewetting of a Lennard-Jones fluid

    NASA Astrophysics Data System (ADS)

    Sweatman, M. B.

    2002-01-01

    The prewetting of a Lennard-Jones fluid is studied using weighted density-functional theory. The intrinsic Helmholtz free-energy functional is separated into repulsive and attractive contributions. An accurate functional for hard spheres is used for the repulsive functional and a weighted density-functional method is used for the attractive part. The results for this theory are compared against mean-field density-functional theory, the theory of Velasco and Tarazona [E. Velasco and P. Tarazona, J. Chem. Phys. 91, 7916 (1989)] and grand canonical ensemble simulation results. The results demonstrate that the weighted density functional for attractive forces may offer a significant increase in accuracy over the other theories. The density-functional and simulation results also indicate that a previous estimate of the wetting temperature for a model of the interaction of argon with solid carbon dioxide, obtained from simulations [J. E. Finn and P. A. Monson, Phys. Rev. A, 39, 6402 (1989)], is incorrect. The weighted density-functional method indicates that triple-point prewetting is observed for this model potential.

  16. Optimization of magneto-optical Kerr setup: Analyzing experimental assemblies using Jones matrix formalism

    NASA Astrophysics Data System (ADS)

    Polisetty, S.; Scheffler, J.; Sahoo, S.; Wang, Yi; Mukherjee, T.; He, Xi; Binek, Ch.

    2008-05-01

    We present a comparative study on an experimental and theoretical optimization of magneto-optical Kerr setups based on photoelastic modulation and phase sensitive detector methodology. The first and second harmonics, Iω ,2ω, of the reflected light intensity are measured for a CoO /Co magnetic reference film. The magnetic field dependence of the optical off-diagonal Fresnel reflection coefficients rps and rsp follows the sample magnetization. Different Kerr setups provide various dependencies of Iω ,2ω on the reflection coefficients and, hence, on the Kerr ellipticity ɛK and rotation θK. Jones matrix formalism has been used to analyze the impact of a systematic variation of relative analyzer and polarizer orientations with respect to each other and with respect to the retardation axis of the modulator involved in longitudinal Kerr setups for incoming s-polarized light. We find one particular setup which maximizes Iω as well as I2ω and maximizes the signal-to-noise ratio. Inefficient setups are characterized by Iω ,2ω intensities involving large nonmagnetic contributions of rp and rs.

  17. Discrete perturbation theory applied to Lennard-Jones and Yukawa potentials.

    PubMed

    Chapela, Gustavo A; del Río, Fernando; Benavides, Ana Laura; Alejandre, José

    2010-12-21

    Discrete perturbation theory (DPT) is a powerful tool to study systems interacting with potentials that are continuous but can be approximated by a piecewise continuous function composed of horizontal segments. The main goal of this work is to analyze the effect of several variables to improve the representation of continuous potentials in order to take advantage of DPT. The main DPT parameters chosen for the purpose are the starting location and size of the horizontal segments used to divide the full range of the potential and its maximum reach. We also studied the effect of having each segment aligned to the left, to the right, or centered on the continuous function. The properties selected to asses the success of this strategy are the orthobaric densities and their corresponding critical points. Critical parameters and orthobaric densities were evaluated by DPT for each of an ample set of variables and compared with their values calculated via discontinuous molecular dynamics. The best sets of DPT parameters are chosen so as to give equations of state that represent accurately the Lennard-Jones and Yukawa fluids.

  18. Enhancement of the droplet nucleation in a dense supersaturated Lennard-Jones vapor.

    PubMed

    Zhukhovitskii, D I

    2016-05-14

    The vapor-liquid nucleation in a dense Lennard-Jones system is studied analytically and numerically. A solution of the nucleation kinetic equations, which includes the elementary processes of condensation/evaporation involving the lightest clusters, is obtained, and the nucleation rate is calculated. Based on the equation of state for the cluster vapor, the pre-exponential factor is obtained. The latter diverges as a spinodal is reached, which results in the nucleation enhancement. The work of critical cluster formation is calculated using the previously developed two-parameter model (TPM) of small clusters. A simple expression for the nucleation rate is deduced and it is shown that the work of cluster formation is reduced for a dense vapor. This results in the nucleation enhancement as well. To verify the TPM, a simulation is performed that mimics a steady-state nucleation experiments in the thermal diffusion cloud chamber. The nucleating vapor with and without a carrier gas is simulated using two different thermostats for the monomers and clusters. The TPM proves to match the simulation results of this work and of other studies.

  19. Enhancement of the droplet nucleation in a dense supersaturated Lennard-Jones vapor

    NASA Astrophysics Data System (ADS)

    Zhukhovitskii, D. I.

    2016-05-01

    The vapor-liquid nucleation in a dense Lennard-Jones system is studied analytically and numerically. A solution of the nucleation kinetic equations, which includes the elementary processes of condensation/evaporation involving the lightest clusters, is obtained, and the nucleation rate is calculated. Based on the equation of state for the cluster vapor, the pre-exponential factor is obtained. The latter diverges as a spinodal is reached, which results in the nucleation enhancement. The work of critical cluster formation is calculated using the previously developed two-parameter model (TPM) of small clusters. A simple expression for the nucleation rate is deduced and it is shown that the work of cluster formation is reduced for a dense vapor. This results in the nucleation enhancement as well. To verify the TPM, a simulation is performed that mimics a steady-state nucleation experiments in the thermal diffusion cloud chamber. The nucleating vapor with and without a carrier gas is simulated using two different thermostats for the monomers and clusters. The TPM proves to match the simulation results of this work and of other studies.

  20. Effect of confinement on the solid-liquid coexistence of Lennard-Jones Fluid

    SciTech Connect

    Das, Chandan K.; Singh, Jayant K.

    2013-11-07

    The solid-liquid coexistence of a Lennard-Jones fluid confined in slit pores of variable pore size, H, is studied using molecular dynamics simulations. Three-stage pseudo-supercritical transformation path of Grochola [J. Chem. Phys. 120(5), 2122 (2004)] and multiple histogram reweighting are employed for the confined system, for various pore sizes ranging from 20 to 5 molecular diameters, to compute the solid-liquid coexistence. The Gibbs free energy difference is evaluated using thermodynamic integration method by connecting solid-liquid phases under confinement via one or more intermediate states without any first order phase transition among them. Thermodynamic melting temperature is found to oscillate with wall separation, which is in agreement with the behavior seen for kinetic melting temperature evaluated in an earlier study. However, thermodynamic melting temperature for almost all wall separations is higher than the bulk case, which is contrary to the behavior seen for the kinetic melting temperature. The oscillation founds to decay at around H = 12, and beyond that pore size dependency of the shift in melting point is well represented by the Gibbs-Thompson equation.

  1. Effect of Size Polydispersity on the Nature of Lennard-Jones Liquids.

    PubMed

    Ingebrigtsen, Trond S; Tanaka, Hajime

    2015-08-27

    Polydisperse fluids are encountered everywhere in biological and industrial processes. These fluids naturally show a rich phenomenology exhibiting fractionation and shifts in critical point and freezing temperatures. We study here the effect of size polydispersity on the basic nature of Lennard-Jones (LJ) liquids, which represent most molecular liquids without hydrogen bonds, via two- and three-dimensional molecular dynamics computer simulations. A single-component liquid constituting spherical particles and interacting via the LJ potential is known to exhibit strong correlations between virial and potential energy equilibrium fluctuations at constant volume. This correlation significantly simplifies the physical description of the liquid, and these liquids are now known as Roskilde-simple (RS) liquids. We show that this simple nature of the single-component LJ liquid is preserved even for very high polydispersities (above 40% polydispersity for the studied uniform distribution). We also investigate isomorphs of moderately polydisperse LJ liquids. Isomorphs are curves in the phase diagram of RS liquids along which structure, dynamics, and some thermodynamic quantities are invariant in dimensionless units. We find that isomorphs are a good approximation even for polydisperse LJ liquids. The theory of isomorphs thus extends readily to size polydisperse fluids and can be used to improve even further the understanding of these intriguing systems.

  2. A multifractal detrended fluctuation analysis of financial market efficiency: Comparison using Dow Jones sector ETF indices

    NASA Astrophysics Data System (ADS)

    Tiwari, Aviral Kumar; Albulescu, Claudiu Tiberiu; Yoon, Seong-Min

    2017-10-01

    This study challenges the efficient market hypothesis, relying on the Dow Jones sector Exchange-Traded Fund (ETF) indices. For this purpose, we use the generalized Hurst exponent and multifractal detrended fluctuation analysis (MF-DFA) methods, using daily data over the timespan from 2000 to 2015. We compare the sector ETF indices in terms of market efficiency between short- and long-run horizons, small and large fluctuations, and before and after the global financial crisis (GFC). Our findings can be summarized as follows. First, there is clear evidence that the sector ETF markets are multifractal in nature. We also find a crossover in the multifractality of sector ETF market dynamics. Second, the utilities and consumer goods sector ETF markets are more efficient compared with the financial and telecommunications sector ETF markets, in terms of price prediction. Third, there are noteworthy discrepancies in terms of market efficiency, between the short- and long-term horizons. Fourth, the ETF market efficiency is considerably diminished after the global financial crisis.

  3. Spherical seed mediated vapor condensation of Lennard-Jones fluid: a density functional theory approach.

    PubMed

    Ghosh, Satinath; Ghosh, Swapan K

    2013-08-07

    Vapor to liquid condensation in presence of spherical seed particle of any arbitrary radius ranging from zero to infinity has been investigated using density functional theory, by modeling the local Helmholtz free energy density functional as well as the density profile at the vapor-liquid interface. A general theory is, thus, obtained which provides the different modes of nucleation based on the size of the seed ranging from zero (corresponding to the homogeneous mode of nucleation) to infinity (corresponding to the heterogeneous nucleation on flat surface). The theory is applied to the Lennard-Jones fluid and the optimized shape (i.e., contact angle) and formation free energy of droplets of any arbitrary size have been obtained in this work. The change of the shape (optimized) with the variation of the size of the liquid droplet as well as with the size of the solid substrate has been studied, thus predicting the shape-size relationship in the course of vapor to liquid heterogeneous nucleation on a spherical solid substrate of any particular size. The spinodal decomposition of vapor has also been observed at higher strength of the solid-fluid interaction. The results have been compared with the results of the conventional classical nucleation theory.

  4. Single-site Lennard-Jones models via polynomial chaos surrogates of Monte Carlo molecular simulation

    NASA Astrophysics Data System (ADS)

    Kadoura, Ahmad; Siripatana, Adil; Sun, Shuyu; Knio, Omar; Hoteit, Ibrahim

    2016-06-01

    In this work, two Polynomial Chaos (PC) surrogates were generated to reproduce Monte Carlo (MC) molecular simulation results of the canonical (single-phase) and the NVT-Gibbs (two-phase) ensembles for a system of normalized structureless Lennard-Jones (LJ) particles. The main advantage of such surrogates, once generated, is the capability of accurately computing the needed thermodynamic quantities in a few seconds, thus efficiently replacing the computationally expensive MC molecular simulations. Benefiting from the tremendous computational time reduction, the PC surrogates were used to conduct large-scale optimization in order to propose single-site LJ models for several simple molecules. Experimental data, a set of supercritical isotherms, and part of the two-phase envelope, of several pure components were used for tuning the LJ parameters (ɛ, σ). Based on the conducted optimization, excellent fit was obtained for different noble gases (Ar, Kr, and Xe) and other small molecules (CH4, N2, and CO). On the other hand, due to the simplicity of the LJ model used, dramatic deviations between simulation and experimental data were observed, especially in the two-phase region, for more complex molecules such as CO2 and C2 H6.

  5. Single-site Lennard-Jones models via polynomial chaos surrogates of Monte Carlo molecular simulation.

    PubMed

    Kadoura, Ahmad; Siripatana, Adil; Sun, Shuyu; Knio, Omar; Hoteit, Ibrahim

    2016-06-07

    In this work, two Polynomial Chaos (PC) surrogates were generated to reproduce Monte Carlo (MC) molecular simulation results of the canonical (single-phase) and the NVT-Gibbs (two-phase) ensembles for a system of normalized structureless Lennard-Jones (LJ) particles. The main advantage of such surrogates, once generated, is the capability of accurately computing the needed thermodynamic quantities in a few seconds, thus efficiently replacing the computationally expensive MC molecular simulations. Benefiting from the tremendous computational time reduction, the PC surrogates were used to conduct large-scale optimization in order to propose single-site LJ models for several simple molecules. Experimental data, a set of supercritical isotherms, and part of the two-phase envelope, of several pure components were used for tuning the LJ parameters (ε, σ). Based on the conducted optimization, excellent fit was obtained for different noble gases (Ar, Kr, and Xe) and other small molecules (CH4, N2, and CO). On the other hand, due to the simplicity of the LJ model used, dramatic deviations between simulation and experimental data were observed, especially in the two-phase region, for more complex molecules such as CO2 and C2 H6.

  6. Pressure Profile for an Associating Lennard-Jones Fluid Confined in a Spherical Cavity.

    PubMed

    Wang, Li-Yuan; Gu, Fang; Wang, Hai-Jun; Sun, Zong-Li

    2017-03-09

    We present the pressure tensor of an associating Lennard-Jones (LJ) fluid confined in a spherical cavity of hard wall, where a high-order density correlation has been taken into account. To give the two-body association potential for calculating the pressure tensor, an angle-average of site-site attraction over all orientations of two particles is performed. Furthermore, the classical density functional theory is employed to obtain the density profile of the confined fluid, by which the normal and tangential pressure profiles are illustrated under various conditions to show the dependence of the pressure tensor on the association strength, number of associating sites, radius of cavity, and bulk density. As an application, the corresponding surface tension is calculated. It is shown that under a strong association interaction (both association strength and the number of associating sites are large), the pressure profiles are depleted from the wall of the cavity instead of the oscillatory behavior under a weak association interaction. Such a tendency is mainly determined by the competition between association interaction and excluded volume interaction. Therefore, the aggregation state and related properties of an associating LJ fluid within a confinement of nanoscale can be efficiently regulated by the association interaction.

  7. Effect of Energy Polydispersity on the Nature of Lennard-Jones Liquids.

    PubMed

    Ingebrigtsen, Trond S; Tanaka, Hajime

    2016-08-11

    In the companion paper [ Ingebrigtsen , T. S. ; Tanaka , H. J. Phys. Chem. B 2015 , 119 , 11052 ] the effect of size polydispersity on the nature of Lennard-Jones (LJ) liquids, which represent most molecular liquids without hydrogen bonds, was studied. More specifically, it was shown that even highly size polydisperse LJ liquids are Roskilde-simple (RS) liquids. RS liquids are liquids with strong correlation between constant volume equilibrium fluctuations of virial and potential energy and are simpler than other types of liquids. Moreover, it was shown that size polydisperse LJ liquids have isomorphs to a good approximation. Isomorphs are curves in the phase diagram of RS liquids along which structure, dynamics, and some thermodynamic quantities are invariant in dimensionless (reduced) units. In this paper, we study the effect of energy polydispersity on the nature of LJ liquids. We show that energy polydisperse LJ liquids are RS liquids. However, a tendency of particle segregation, which increases with the degree of polydispersity, leads to a loss of strong virial-potential energy correlation but is mitigated by increasing temperature and/or density. Isomorphs are a good approximation also for energy polydisperse LJ liquids, although particle-resolved quantities display a somewhat poorer scaling compared to the mean quantities along the isomorph.

  8. Thermal conductivity of the Lennard-Jones liquid by molecular dynamics calculations

    NASA Astrophysics Data System (ADS)

    Vogelsang, R.; Hoheisel, C.; Ciccotti, G.

    1987-06-01

    Precise results for the thermal conductivity of the Lennard-Jones liquid obtained by equilibrium molecular dynamics (MD) are presented. These are compared in detail with previous nonequilibrium MD results. Effects due to the truncation of the potential and the particle number dependence are considered. The contributions of the partial correlation functions to the total one were separately calculated. Main results are: (i) in contrast to the viscosity, the thermal conductivity is rather insensitive to the MD conditions, even for the state corresponding virtually to the triple point of argon. The reason for this originates from the simple short ranged time decay of the correlation function. (ii) For the states considered, the partial correlation function involving the ``potential-potential'' term governs the transport coefficient. (iii) Nonequilibrium MD and MD give consistent values, except for the nonequilibrium method devised by Heyes which generates data far off the range permitted by the error bars. (iv) The computed thermal conductivities fall well in line with experimental data for argon.

  9. Optimization of MOKE Setups: Analyzing Experimental Assemblies Using Jones Matrix Formalism

    NASA Astrophysics Data System (ADS)

    Polisetty, Srinivas; Scheffler, Jeremy; Sahoo, Sarbeswar; Binek, Christian

    2008-03-01

    We report on the optimization of Magneto Optical Kerr setups. Photoelastic modulation and phase sensitive detector methodology have been used to measure the first and second harmonics of the reflected light intensity related to the magnetization-dependent off-diagonal reflection coefficients rps/sp of the sample's dielectric tensor. The latter elements determine the Kerr ellipticity ɛK and rotation θK. Jones matrix formalism has been used to analyze a large variety of arrangements of the optical elements involved in setups for longitudinal Kerr measurements with incoming s-polarized light. Relative analyzer and polarizer orientations have been varied with respect to each other and with respect to the retardation axis of the modulator. Different configurations have been analyzed and experimentally studied by measuring magnetic Kerr-hysteresis loops on a Co/CoO bilayer sample. We find that one configuration stands out by doubling the first as well as second harmonic intensities and, hence, the signal to noise ratio. Inefficient setups show first and second harmonic signals involving non-magnetic background contributions of rp and rs.

  10. Nucleation of liquid droplets and voids in a stretched Lennard-Jones fcc crystal.

    PubMed

    Baidakov, Vladimir G; Tipeev, Azat O

    2015-09-28

    The method of molecular dynamics simulation has been used to investigate the phase decay of a metastable Lennard-Jones face-centered cubic crystal at positive and negative pressures. It is shown that at high degrees of metastability, crystal decay proceeds through the spontaneous formation and growth of new-phase nuclei. It has been found that there exists a certain boundary temperature. Below this temperature, the crystal phase disintegrates as the result of formation of voids, and above, as a result of formation of liquid droplets. The boundary temperature corresponds to the temperature of cessation of a crystal-liquid phase equilibrium when the melting line comes in contact with the spinodal of the stretched liquid. The results of the simulations are interpreted in the framework of classical nucleation theory. The thermodynamics of phase transitions in solids has been examined with allowance for the elastic energy of stresses arising owing to the difference in the densities of the initial and the forming phases. As a result of the action of elastic forces, at negative pressures, the boundary of the limiting superheating (stretching) of a crystal approaches the spinodal, on which the isothermal bulk modulus of dilatation becomes equal to zero. At the boundary of the limiting superheating (stretching), the shape of liquid droplets and voids is close to the spherical one.

  11. Determination of anharmonic free energy contributions: Low temperature phases of the Lennard-Jones system.

    PubMed

    Calero, C; Knorowski, C; Travesset, A

    2016-03-28

    We investigate a general method to calculate the free energy of crystalline solids by considering the harmonic approximation and quasistatically switching the anharmonic contribution. The advantage of this method is that the harmonic approximation provides an already very accurate estimate of the free energy, and therefore the anharmonic term is numerically very small and can be determined to high accuracy. We further show that the anharmonic contribution to the free energy satisfies a number of exact inequalities that place constraints on its magnitude and allows approximate but fast and accurate estimates. The method is implemented into a readily available general software by combining the code HOODLT (Highly Optimized Object Oriented Dynamic Lattice Theory) for the harmonic part and the molecular dynamics (MD) simulation package HOOMD-blue for the anharmonic part. We use the method to calculate the low temperature phase diagram for Lennard-Jones particles. We demonstrate that hcp is the equilibrium phase at low temperature and pressure and obtain the coexistence curve with the fcc phase, which exhibits reentrant behavior. Several implications of the method are discussed.

  12. Tolman length and rigidity constants of the Lennard-Jones fluid.

    PubMed

    Wilhelmsen, Øivind; Bedeaux, Dick; Reguera, David

    2015-02-14

    It is well-known that the surface tension of small droplets and bubbles deviates significantly from that at the planar interface. In this work, we analyze the leading corrections in the curvature expansion of the surface tension, i.e., the Tolman length and the rigidity constants, using a "hybrid" square gradient theory, where the local Helmholtz energy density is described by an accurate equation of state. We particularize this analysis for the case of the truncated and shifted Lennard-Jones fluid, and are then able to reproduce the surface tensions and Tolman length from recent molecular dynamics simulations within their accuracy. The obtained constants in the curvature expansion depend little on temperature, except in the vicinity of the critical point. When the bubble/droplet radius becomes comparable to the interfacial width at coexistence, the critical bubble/droplet prefers to change its density, rather than to decrease its size, and the curvature expansion is no longer sufficient to describe the change in surface tension. We find that the radius of the bubble/droplet in this region is proportional to the correlation length between fluctuations in the liquid-phase.

  13. Freezing and melting line invariants of the Lennard-Jones system.

    PubMed

    Costigliola, Lorenzo; Schrøder, Thomas B; Dyre, Jeppe C

    2016-06-07

    The invariance of several structural and dynamical properties of the Lennard-Jones (LJ) system along the freezing and melting lines is interpreted in terms of isomorph theory. First the freezing/melting lines of the LJ system are shown to be approximated by isomorphs. Then we show that the invariants observed along the freezing and melting isomorphs are also observed on other isomorphs in the liquid and crystalline phases. The structure is probed by the radial distribution function and the structure factor and dynamics are probed by the mean-square displacement, the intermediate scattering function, and the shear viscosity. Studying these properties with reference to isomorph theory explains why the known single-phase melting criteria hold, e.g., the Hansen-Verlet and the Lindemann criteria, and why the Andrade equation for the viscosity at freezing applies, e.g., for most liquid metals. Our conclusion is that these empirical rules and invariants can all be understood from isomorph theory and that the invariants are not peculiar to the freezing and melting lines, but hold along all isomorphs.

  14. Surface tension of the two center Lennard-Jones plus point dipole fluid.

    PubMed

    Werth, Stephan; Horsch, Martin; Hasse, Hans

    2016-02-07

    Molecular dynamics simulations are used for systematically studying the surface tension of the two center Lennard-Jones plus point dipole (2CLJD) model fluid. In a dimensionless representation, this model fluid has two parameters describing the elongation and the dipole moment. These parameters were varied in the entire range relevant for describing real fluids resulting in a grid of 38 individual models. For each model, the surface tension was determined at temperatures between 60% and 90% of the critical temperature. For completeness, the vapor pressure and the saturated densities were also determined. The latter results agree well with the literature data, whereas for the surface tension, only few data were previously available. From the present results, an empirical correlation for the surface tension of the 2CLJD model as a function of the model parameters is developed. The correlation is used to predict the surface tension of 46 2CLJD molecular models from the literature, which were adjusted to bulk properties, but not to interfacial properties. The results are compared to the experimental data. The molecular models overestimate the surface tension, and deviations between the predictions and experimental data are below 12% on average.

  15. Effect of confinement on the solid-liquid coexistence of Lennard-Jones fluid.

    PubMed

    Das, Chandan K; Singh, Jayant K

    2013-11-07

    The solid-liquid coexistence of a Lennard-Jones fluid confined in slit pores of variable pore size, H, is studied using molecular dynamics simulations. Three-stage pseudo-supercritical transformation path of Grochola [J. Chem. Phys. 120(5), 2122 (2004)] and multiple histogram reweighting are employed for the confined system, for various pore sizes ranging from 20 to 5 molecular diameters, to compute the solid-liquid coexistence. The Gibbs free energy difference is evaluated using thermodynamic integration method by connecting solid-liquid phases under confinement via one or more intermediate states without any first order phase transition among them. Thermodynamic melting temperature is found to oscillate with wall separation, which is in agreement with the behavior seen for kinetic melting temperature evaluated in an earlier study. However, thermodynamic melting temperature for almost all wall separations is higher than the bulk case, which is contrary to the behavior seen for the kinetic melting temperature. The oscillation founds to decay at around H = 12, and beyond that pore size dependency of the shift in melting point is well represented by the Gibbs-Thompson equation.

  16. Molecular dynamics study of nanobubbles in the equilibrium Lennard-Jones fluid.

    PubMed

    Zhukhovitskii, D I

    2013-10-28

    We employ a model, in which the density fluctuations in a bulk liquid are represented as presence of the clusters of molecules with the lowered number of nearest neighbors (number of bonds). The nanobubble size distribution is calculated on the basis of a close analogy between the surface part of the work of formation for a cluster and for a nanobubble. The pre-exponential factor for this distribution is related to the fluid compressibility. Estimates made for different liquids show that it can be noticeably different from that adopted in the classical nucleation theory (CNT). Molecular dynamics (MD) simulation is performed for a liquid inside a macroscopic droplet of molecules interacting via the Lennard-Jones potential plus a long-range tail. The nanobubbles are identified by clusters of bond-deficient particles with the optimum number of bonds that provide the maximum nanobubble number density and maximum resolvable nanobubble equimolar size. The results of MD simulation are in qualitatively better agreement with proposed theory than with CNT.

  17. Lennard-Jones systems near solid walls: computing interfacial free energies from molecular simulation methods.

    PubMed

    Benjamin, Ronald; Horbach, Jürgen

    2013-08-28

    Different computational techniques in combination with molecular dynamics computer simulation are used to determine the wall-liquid and the wall-crystal interfacial free energies of a modified Lennard-Jones (LJ) system in contact with a solid wall. Two different kinds of solid walls are considered: a flat structureless wall and a structured wall consisting of an ideal crystal with the particles rigidly attached to fcc lattice sites. Interfacial free energies are determined by a thermodynamic integration scheme, the anisotropy of the pressure tensor, the non-equilibrium work method based on Bennett acceptance criteria, and a method using Cahn's adsorption equations based on the interfacial thermodynamics of Gibbs. For the flat wall, interfacial free energies as a function of different densities of the LJ liquid and as a function of temperature along the coexistence curve are calculated. In the case of a structured wall, the interaction strength between the wall and the LJ system and the lattice constant of the structured wall are varied. Using the values of the wall-liquid and wall-crystal interfacial energies along with the value for the crystal-liquid interfacial free energy determined previously for the same system by the "cleaving potential method," we obtain the contact angle as a function of various parameters; in particular, the conditions are found under which partial wetting occurs.

  18. Smart imaging for power-efficient extraction of Viola-Jones local descriptors

    NASA Astrophysics Data System (ADS)

    Fernández-Berni, J.; Carmona-Galán, R. A.; del Río, R.; Leñero-Bardallo, Juan A.; Suárez-Cambre, M.; Rodríguez-Vázquez, Á.

    2014-03-01

    In computer vision, local descriptors permit to summarize relevant visual cues through feature vectors. These vectors constitute inputs for trained classifiers which in turn enable different high-level vision tasks. While local descriptors certainly alleviate the computation load of subsequent processing stages by preventing them from handling raw images, they still have to deal with individual pixels. Feature vector extraction can thus become a major limitation for conventional embedded vision hardware. In this paper, we present a power-efficient sensing processing array conceived to provide the computation of integral images at different scales. These images are intermediate representations that speed up feature extraction. In particular, the mixed-signal array operation is tailored for extraction of Haar-like features. These features feed the cascade of classifiers at the core of the Viola-Jones framework. The processing lattice has been designed for the standard UMC 0.18μm 1P6M CMOS process. In addition to integral image computation, the array can be reprogrammed to deliver other early vision tasks: concurrent rectangular area sum, block-wise HDR imaging, Gaussian pyramids and image pre-warping for subsequent reduced kernel filtering.

  19. Optimization method of superpixel analysis for multi-contrast Jones matrix tomography (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Miyazawa, Arata; Hong, Young-Joo; Makita, Shuichi; Kasaragod, Deepa K.; Miura, Masahiro; Yasuno, Yoshiaki

    2017-02-01

    Local statistics are widely utilized for quantification and image processing of OCT. For example, local mean is used to reduce speckle, local variation of polarization state (degree-of-polarization-uniformity (DOPU)) is used to visualize melanin. Conventionally, these statistics are calculated in a rectangle kernel whose size is uniform over the image. However, the fixed size and shape of the kernel result in a tradeoff between image sharpness and statistical accuracy. Superpixel is a cluster of pixels which is generated by grouping image pixels based on the spatial proximity and similarity of signal values. Superpixels have variant size and flexible shapes which preserve the tissue structure. Here we demonstrate a new superpixel method which is tailored for multifunctional Jones matrix OCT (JM-OCT). This new method forms the superpixels by clustering image pixels in a 6-dimensional (6-D) feature space (spatial two dimensions and four dimensions of optical features). All image pixels were clustered based on their spatial proximity and optical feature similarity. The optical features are scattering, OCT-A, birefringence and DOPU. The method is applied to retinal OCT. Generated superpixels preserve the tissue structures such as retinal layers, sclera, vessels, and retinal pigment epithelium. Hence, superpixel can be utilized as a local statistics kernel which would be more suitable than a uniform rectangle kernel. Superpixelized image also can be used for further image processing and analysis. Since it reduces the number of pixels to be analyzed, it reduce the computational cost of such image processing.

  20. Modeling Aggregation Processes of Lennard-Jones particles Via Stochastic Networks

    NASA Astrophysics Data System (ADS)

    Forman, Yakir; Cameron, Maria

    2017-07-01

    We model an isothermal aggregation process of particles/atoms interacting according to the Lennard-Jones pair potential by mapping the energy landscapes of each cluster size N onto stochastic networks, computing transition probabilities from the network for an N-particle cluster to the one for N+1, and connecting these networks into a single joint network. The attachment rate is a control parameter. The resulting network representing the aggregation of up to 14 particles contains 6427 vertices. It is not only time-irreversible but also reducible. To analyze its transient dynamics, we introduce the sequence of the expected initial and pre-attachment distributions and compute them for a wide range of attachment rates and three values of temperature. As a result, we find the configurations most likely to be observed in the process of aggregation for each cluster size. We examine the attachment process and conduct a structural analysis of the sets of local energy minima for every cluster size. We show that both processes taking place in the network, attachment and relaxation, lead to the dominance of icosahedral packing in small (up to 14 atom) clusters.

  1. The two-dimensional Lennard-Jones system: Sublimation, vaporization, and melting

    NASA Astrophysics Data System (ADS)

    Phillips, James M.; Bruch, L. W.; Murphy, R. D.

    1981-11-01

    The solid-vapor equilibrium line and the liquid-vapor equilibrium line near the melting region for classical two-dimensional systems of particles interacting by Lennard-Jones (12,6) pair potentials are determined from Monte Carlo simulations with 224 particles. Structural and thermodynamic properties are evaluated for homogeneous single phases on both sides of the melting transition. The Monte Carlo results show that a cell model approximation to the solid phase has good accuracy for most of the anharmonic 2D solid conditions of this work. Free energies for solid states are constructed starting from the low temperature quasiharmonic solid; for the 2D liquid states the starting point is the virial expansion for the dilute gas. From these free energies the triple-point melting of the periodically extended 224-particle system is found to be first order and the latent heat of melting is determined. Graphic displays are obtained showing the occurrence of dislocation pairs, voids, particle exchange, and mixed phases. The implementation of the simulation is discussed, including problems of superheating and the achievement of equilibrium.

  2. Triple point of Lennard-Jones fluid in slit nanopore: solidification of critical condensate.

    PubMed

    Kanda, Hideki; Miyahara, Minoru; Higashitani, Ko

    2004-04-01

    We report the results of a molecular dynamics simulation that looked for the triple point of Lennard-Jones fluid in slit-shaped nanopores. The simulation method employed for this purpose is able to maintain vapor-liquid coexistence in a nanopore at a specific equilibrium bulk-phase pressure. The triple point is the freezing point of the critical condensate. The triple-point temperature could be higher or lower than the bulk triple point, depending on the pore size. This is thought to be due to two opposing factors: the elevating effect of the pore-wall potential energy, and the depressing effect of the capillary condensate's tensile condition. Because of the cancellation, the deviation of the triple-point temperature from the bulk triple-point temperature was not considered significant. The pressure of the triple point, however, was significantly different from that of the bulk triple point. A simple model to describe the triple point is developed and shown to agree well with the results of the simulation. The importance of the two factors in nanoscale pores, which cannot be described by the classic Gibbs-Thomson equation, is emphasized.

  3. Local elasticity map and plasticity in a model Lennard-Jones glass.

    PubMed

    Tsamados, Michel; Tanguy, Anne; Goldenberg, Chay; Barrat, Jean-Louis

    2009-08-01

    In this work we calculate the local elastic moduli in a weakly polydispersed two-dimensional Lennard-Jones glass undergoing a quasistatic shear deformation at zero temperature. The numerical method uses coarse-grained microscopic expressions for the strain, displacement, and stress fields. This method allows us to calculate the local elasticity tensor and to quantify the deviation from linear elasticity (local Hooke's law) at different coarse-graining scales. From the results a clear picture emerges of an amorphous material with strongly spatially heterogeneous elastic moduli that simultaneously satisfies Hooke's law at scales larger than a characteristic length scale of the order of five interatomic distances. At this scale, the glass appears as a composite material composed of a rigid scaffolding and of soft zones. Only recently calculated in nonhomogeneous materials, the local elastic structure plays a crucial role in the elastoplastic response of the amorphous material. For a small macroscopic shear strain, the structures associated with the nonaffine displacement field appear directly related to the spatial structure of the elastic moduli. Moreover, for a larger macroscopic shear strain we show that zones of low shear modulus concentrate most of the strain in the form of plastic rearrangements. The spatiotemporal evolution of this local elasticity map and its connection with long term dynamical heterogeneity as well as with the plasticity in the material is quantified. The possibility to use this local parameter as a predictor of subsequent local plastic activity is also discussed.

  4. Widom line for the liquid-gas transition in Lennard-Jones system.

    PubMed

    Brazhkin, V V; Fomin, Yu D; Lyapin, A G; Ryzhov, V N; Tsiok, E N

    2011-12-08

    The locus of extrema (ridges) for heat capacity, thermal expansion coefficient, compressibility, and density fluctuations for model particle systems with Lennard-Jones (LJ) potential in the supercritical region have been obtained. It was found that the ridges for different thermodynamic values virtually merge into a single Widom line at T < 1.1T(c) and P < 1.5P(c) and become practically completely smeared at T < 2.5T(c) and P < 10P(c), where T(c) and P(c) are the critical temperature and pressure. The ridge for heat capacity approaches close to critical isochore, whereas the lines of extrema for other values correspond to density decrease. The lines corresponding to the supercritical maxima for argon and neon are in good agreement with the computer simulation data for LJ fluid. The behavior of the ridges for LJ fluid, in turn, is close to that for the supercritical van der Waals fluid, which is indicative of a fairly universal behavior of the Widom line for a liquid-gas transition.

  5. A multiscale transport model for binary Lennard Jones mixtures in slit nanopores

    NASA Astrophysics Data System (ADS)

    Bhadauria, Ravi; Aluru, N. R.

    2016-11-01

    We present a quasi-continuum multiscale hydrodynamic transport model for one dimensional isothermal, non-reacting binary mixture confined in slit shaped nanochannels. We focus on species transport equation that includes the viscous dissipation and interspecies diffusion term of the Maxwell-Stefan form. Partial viscosity variation is modeled by van der Waals one fluid approximation and the Local Average Density Method. We use friction boundary conditions where the wall-species friction parameter is computed using a novel species specific Generalized Langevin Equation model. The transport model accuracy is tested by predicting the velocity profiles of Lennard-Jones (LJ) methane-hydrogen and LJ methane-argon mixtures in graphene slit channels of different width. The resultant slip length from the continuum model is found to be invariant of channel width for a fixed mixture molar concentration. The mixtures considered are observed to behave as single species pseudo fluid, with the friction parameter displaying a linear dependence on the molar composition. The proposed model yields atomistic level accuracy with continuum scale efficiency.

  6. A battle for compensation for Welsh coal miners: JS Haldane v "Sericite" Jones, 1932-1934.

    PubMed

    Greenberg, M

    1997-09-01

    Toward the end of the 1920s, technical advances in mining led to an increase in airborne burdens of dust in the South Wales coal mines. This coincided with a dramatic increase in the incidence of disability and death from respiratory disease among the miners. For their condition to be compensable, claimants were required to have worked with rock containing more than 50% 'free silica.' Dr W.R. Jones, a mining geologist, was asked to help obtain compensation for those claimants who could not satisfy the 'free silica' condition. He was unable to identify high-silica rocks where none had been said to exist. He did however, successfully argue the brief against the eminent Professor J.S. Haldane (who was the dominant authority, having had lengthy experience in the field of health and mining), for the fibrous form of sericite being commonly the important agent responsible for pneumoconiosis. As a consequence, the category of miner eligible for compensation was broadened. Evidence was gathered worldwide that supported the hypothesis that silicates and not just crystalline silica could cause pneumoconiosis. Despite the suspicions raised about the special power of mineral fibers during this public debate, some 40 years were to elapse before potential health hazards from fibers other than asbestos were to be taken seriously and investigated.

  7. How long the singular value decomposed entropy predicts the stock market? - Evidence from the Dow Jones Industrial Average Index

    NASA Astrophysics Data System (ADS)

    Gu, Rongbao; Shao, Yanmin

    2016-07-01

    In this paper, a new concept of multi-scales singular value decomposition entropy based on DCCA cross correlation analysis is proposed and its predictive power for the Dow Jones Industrial Average Index is studied. Using Granger causality analysis with different time scales, it is found that, the singular value decomposition entropy has predictive power for the Dow Jones Industrial Average Index for period less than one month, but not for more than one month. This shows how long the singular value decomposition entropy predicts the stock market that extends Caraiani's result obtained in Caraiani (2014). On the other hand, the result also shows an essential characteristic of stock market as a chaotic dynamic system.

  8. Non-equilibrium surface tension of the vapour-liquid interface of active Lennard-Jones particles.

    PubMed

    Paliwal, Siddharth; Prymidis, Vasileios; Filion, Laura; Dijkstra, Marjolein

    2017-08-28

    We study a three-dimensional system of self-propelled Brownian particles interacting via the Lennard-Jones potential. Using Brownian dynamics simulations in an elongated simulation box, we investigate the steady states of vapour-liquid phase coexistence of active Lennard-Jones particles with planar interfaces. We measure the normal and tangential components of the pressure tensor along the direction perpendicular to the interface and verify mechanical equilibrium of the two coexisting phases. In addition, we determine the non-equilibrium interfacial tension by integrating the difference of the normal and tangential components of the pressure tensor and show that the surface tension as a function of strength of particle attractions is well fitted by simple power laws. Finally, we measure the interfacial stiffness using capillary wave theory and the equipartition theorem and find a simple linear relation between surface tension and interfacial stiffness with a proportionality constant characterized by an effective temperature.

  9. Non-equilibrium surface tension of the vapour-liquid interface of active Lennard-Jones particles

    NASA Astrophysics Data System (ADS)

    Paliwal, Siddharth; Prymidis, Vasileios; Filion, Laura; Dijkstra, Marjolein

    2017-08-01

    We study a three-dimensional system of self-propelled Brownian particles interacting via the Lennard-Jones potential. Using Brownian dynamics simulations in an elongated simulation box, we investigate the steady states of vapour-liquid phase coexistence of active Lennard-Jones particles with planar interfaces. We measure the normal and tangential components of the pressure tensor along the direction perpendicular to the interface and verify mechanical equilibrium of the two coexisting phases. In addition, we determine the non-equilibrium interfacial tension by integrating the difference of the normal and tangential components of the pressure tensor and show that the surface tension as a function of strength of particle attractions is well fitted by simple power laws. Finally, we measure the interfacial stiffness using capillary wave theory and the equipartition theorem and find a simple linear relation between surface tension and interfacial stiffness with a proportionality constant characterized by an effective temperature.

  10. Theoretical consideration of osmotic pressure in aqueous protein/salt systems based on extended hard core Lennard-Jones potential

    NASA Astrophysics Data System (ADS)

    Pai, Sung Jin; Bae, Young Chan

    2010-10-01

    A simple and analytical pair potential function was developed to represent the osmotic pressures in aqueous protein/salt systems under various conditions. Based on a hard core Lennard-Jones (HCLJ) potential model, the new potential function considers various interactions by extending the attractive Lennard-Jones potential. A temperature-dependent coefficient term was introduced to take into account the specific properties of given materials. Comparison of the new potential function with the HCLJ model in hydrocarbon and water systems showed that consideration of the temperature dependence in the potential function was effective, especially for strong polar systems such as water. To predict the osmotic pressures of aqueous lysozyme/(NH4)2SO4 solutions of various ionic strength and pH, the energy parameters of lysozyme were correlated with the experimental cloud point temperature. The proposed model agreed fairly well with the experimental osmotic pressure data with only previously obtained parameters.

  11. Theoretical consideration of osmotic pressure in aqueous protein/salt systems based on extended hard core Lennard-Jones potential.

    PubMed

    Pai, Sung Jin; Bae, Young Chan

    2010-10-21

    A simple and analytical pair potential function was developed to represent the osmotic pressures in aqueous protein/salt systems under various conditions. Based on a hard core Lennard-Jones (HCLJ) potential model, the new potential function considers various interactions by extending the attractive Lennard-Jones potential. A temperature-dependent coefficient term was introduced to take into account the specific properties of given materials. Comparison of the new potential function with the HCLJ model in hydrocarbon and water systems showed that consideration of the temperature dependence in the potential function was effective, especially for strong polar systems such as water. To predict the osmotic pressures of aqueous lysozyme/(NH(4))(2)SO(4) solutions of various ionic strength and pH, the energy parameters of lysozyme were correlated with the experimental cloud point temperature. The proposed model agreed fairly well with the experimental osmotic pressure data with only previously obtained parameters.

  12. Fundamental measure density functional theory studies on the freezing of binary hard-sphere and Lennard-Jones mixtures

    SciTech Connect

    Warshavsky, Vadim B.; Song, Xueyu

    2008-07-18

    Free energies and correlation functions of liquid and solid hard-sphere (HS) mixtures are calculated using the fundamental measure density functional theory. Using the thermodynamic perturbation theory the free energies of solid and liquid Lennard-Jones (LJ) mixtures are obtained from correlation functions of HS systems within a single theoretical approach. The resulting azeotrope- and spindle-type solid-liquid phase diagrams of HS and LJ binary mixtures are in good agreement with the corresponding ones from computer simulations.

  13. Lennard-Jones Lattice Summation in Bilayer Simulations Has Critical Effects on Surface Tension and Lipid Properties.

    PubMed

    Wennberg, Christian L; Murtola, Teemu; Hess, Berk; Lindahl, Erik

    2013-08-13

    The accuracy of electrostatic interactions in molecular dynamics advanced tremendously with the introduction of particle-mesh Ewald (PME) summation almost 20 years ago. Lattice summation electrostatics is now the de facto standard for most types of biomolecular simulations, and in particular, for lipid bilayers, it has been a critical improvement due to the large charges typically present in zwitterionic lipid headgroups. In contrast, Lennard-Jones interactions have continued to be handled with increasingly longer cutoffs, partly because few alternatives have been available despite significant difficulties in tuning cutoffs and parameters to reproduce lipid properties. Here, we present a new Lennard-Jones PME implementation applied to lipid bilayers. We confirm that long-range contributions are well approximated by dispersion corrections in simple systems such as pentadecane (which makes parameters transferable), but for inhomogeneous and anisotropic systems such as lipid bilayers there are large effects on surface tension, resulting in up to 5.5% deviations in area per lipid and order parameters-far larger than many differences for which reparameterization has been attempted. We further propose an approximation for combination rules in reciprocal space that significantly reduces the computational cost of Lennard-Jones PME and makes accurate treatment of all nonbonded interactions competitive with simulations employing long cutoffs. These results could potentially have broad impact on important applications such as membrane proteins and free energy calculations.

  14. Riemannian geometry study of vapor-liquid phase equilibria and supercritical behavior of the Lennard-Jones fluid.

    PubMed

    May, Helge-Otmar; Mausbach, Peter

    2012-03-01

    The behavior of thermodynamic response functions and the thermodynamic scalar curvature in the supercritical region have been studied for a Lennard-Jones fluid based on a revised modified Benedict-Webb-Rubin equation of state. Response function extrema are sometimes used to estimate the Widom line, which is characterized by the maxima of the correlation lengths. We calculated the Widom line for the Lennard-Jones fluid without using any response function extrema. Since the volume of the correlation length is proportional to the Riemannian thermodynamic scalar curvature, the locus of the Widom line follows the slope of maximum curvature. We show that the slope of the Widom line follows the slope of the isobaric heat capacity maximum only in the close vicinity of the critical point and that, therefore, the use of response function extrema in this context is problematic. Furthermore, we constructed the vapor-liquid coexistence line for the Lennard-Jones fluid using the fact that the correlation length, and therefore the thermodynamic scalar curvature, must be equal in the two coexisting phases. We compared the resulting phase envelope with those from simulation data where multiple histogram reweighting was used and found striking agreement between the two methods.

  15. A critical study of the simulation of the liquid-vapour interface of a Lennard-Jones fluid

    NASA Astrophysics Data System (ADS)

    Holcomb, Cynthia D.; Clancy, Paulette; Zollweg, John A.

    Despite the fact that the surface tension for a Lennard-Jones fluid has been simulated many times in the past, there is some considerable disagreement between the results. This paper calculates the surface tension and density profiles for the liquid-vapour interface of a Lennard-Jones fluid using molecular dynamics (MD) simulation techniques for a variety of system sizes, film thicknesses, interfacial areas, interatomic potential cut-offs, and temperatures. The results are compared with previous work in order to resolve some of the discrepancies of the past work. Combining this work with some reliable results from the past, the minimum system size, film thickness, and equilibration time necessary for the accurate description of the surface tension was determined. Using simulation results calculated for computationally-economic values of the potential cut-off, the surface tension was extrapolated to the full potential value using a tail correction and the results compared to simulations performed with longer cut-offs. The results indicated the possibility of obtaining estimates of the surface tension for models employing a large cut-off from those with a more moderate cut-off value. The criteria established for obtaining accurate results for the pure components was applied to binary mixtures of Lennard-Jones particles approximating mixtures of argon and krypton. The preferential adsorption at the interface was examined, the tail correction was applied to the mixtures, and the 'corrected' surface tensions compared to experimental results.

  16. Radiographic factors and effect of fifth metatarsal Jones and diaphyseal stress fractures on participation in the NFL.

    PubMed

    Carreira, Dominic S; Sandilands, Scott M

    2013-04-01

    Jones fracture and proximal diaphyseal stress fracture of the fifth metatarsal have been associated with prolonged healing times and nonunions. We hypothesized that the Jones fracture and proximal diaphyseal stress fracture have a high incidence in elite collegiate football players and that they lead to a decrease in participation in the NFL. Also, we hypothesized that these fractures are associated with a cavovarus foot alignment. The database collected by a single NFL team during the 2004 to 2009 NFL Combines was reviewed to identify players with Jones and proximal diaphyseal fifth metatarsal fractures. A total of 74 fifth metatarsal fractures were identified in 68 players. Subsequent participation data also were collected through the NFL.com website and included games played and years played. Digital plain radiographs and additional imaging studies also were reviewed to determine the extent of healing, types of fixation utilized, and foot alignment. The locations of fractures in the proximal fifth metatarsal were 45 (61%) in the Jones area, 15 (20%) in the proximal diaphyseal area, and 14 (19%) of indeterminate location. The number of patients treated with intramedullary fixation was 55/74 (74%). Of 74 proximal fifth metatarsal fractures, 9 (12.2%) were nonunions at the time of the NFL Combine medical examinations. With the numbers available, the average number of games played in the NFL was not significantly different in the fifth metatarsal fracture group, 16.9, compared to the control group, 24.9 (P > .05). The average number of games started was 7.4 in the fracture group versus 12.1 in the control group (P > .05). No significant differences were noted in the number of years played in the NFL. Except for talonavicular angle measurements, all measurements of coronal plane alignment demonstrated significant differences across groups, but no differences were noted in sagittal plane alignment. No statistically significant difference was noted in participation in

  17. Clarifying hierarchical age-period-cohort models: A rejoinder to Bell and Jones.

    PubMed

    Reither, Eric N; Land, Kenneth C; Jeon, Sun Y; Powers, Daniel A; Masters, Ryan K; Zheng, Hui; Hardy, Melissa A; Keyes, Katherine M; Fu, Qiang; Hanson, Heidi A; Smith, Ken R; Utz, Rebecca L; Yang, Y Claire

    2015-11-01

    Previously, Reither et al. (2015) demonstrated that hierarchical age-period-cohort (HAPC) models perform well when basic assumptions are satisfied. To contest this finding, Bell and Jones (2015) invent a data generating process (DGP) that borrows age, period and cohort effects from different equations in Reither et al. (2015). When HAPC models applied to data simulated from this DGP fail to recover the patterning of APC effects, B&J reiterate their view that these models provide "misleading evidence dressed up as science." Despite such strong words, B&J show no curiosity about their own simulated data--and therefore once again misapply HAPC models to data that violate important assumptions. In this response, we illustrate how a careful analyst could have used simple descriptive plots and model selection statistics to verify that (a) period effects are not present in these data, and (b) age and cohort effects are conflated. By accounting for the characteristics of B&J's artificial data structure, we successfully recover the "true" DGP through an appropriately specified model. We conclude that B&Js main contribution to science is to remind analysts that APC models will fail in the presence of exact algebraic effects (i.e., effects with no random/stochastic components), and when collinear temporal dimensions are included without taking special care in the modeling process. The expanded list of coauthors on this commentary represents an emerging consensus among APC scholars that B&J's essential strategy--testing HAPC models with data simulated from contrived DGPs that violate important assumptions--is not a productive way to advance the discussion about innovative APC methods in epidemiology and the social sciences. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Specifics of freezing of Lennard-Jones fluid confined to molecularly thin layers

    NASA Astrophysics Data System (ADS)

    Vishnyakov, Aleksey; Neimark, Alexander V.

    2003-04-01

    Freezing of a Lennard-Jones fluid between solid surfaces was studied using grand canonical Monte Carlo and molecular dynamics simulations. We explored the formation of frozen phases of hexagonal and orthorhombic symmetry in mono-, bi-, and tri-layer structures. The freezing transition, the type of lattice, and translational and orientational ordering were identified on the basis of orientational order parameters, in-plane two-body and three-body translational correlation functions, orientational correlation functions, and analysis of molecular mobilities. We have found that the freezing temperature is a nonmonotonous function of the pore width: orthorhombic bi-layer freezes at lower temperatures than hexagonal monolayer and hexagonal bi-layer. As the pore width increases, the transition from a hexagonal monolayer to an orthorhombic bi-layer occurred via disordered liquidlike and quasi-long-range four-fold ordered bi-layers. The latter, "quadratic" structure is characterized by an algebraically decaying four-fold orientational correlation function. The transition from crystalline hexagonal bi-layer to orthorhombic tri-layer occurs through a bi-layer structure with two uncoupled hexagonal monolayers. The quadratic phase was observed also as an intermediate structure during freezing of a liquidlike bi-layer into an orthorhombic quasi-crystal. The formation of the quadratic phase was associated with step-wise densification of fluid, a sharp increase of the local orientational order parameter, and a significant reduction of fluid mobility. In the process of solidification, the system passed through a sequence of high-density jammed structures, in which the four-fold symmetry developed progressively, as the temperature decreased.

  19. Drying and wetting transitions of a Lennard-Jones fluid: Simulations and density functional theory

    NASA Astrophysics Data System (ADS)

    Evans, Robert; Stewart, Maria C.; Wilding, Nigel B.

    2017-07-01

    We report a theoretical and simulation study of the drying and wetting phase transitions of a truncated Lennard-Jones fluid at a flat structureless wall. Binding potential calculations predict that the nature of these transitions depends on whether the wall-fluid attraction has a long ranged (LR) power law decay or is instead truncated, rendering it short ranged (SR). Using grand canonical Monte Carlo simulation and classical density functional theory, we examine both cases in detail. We find that for the LR case wetting is first order, while drying is continuous (critical) and occurs exactly at zero attractive wall strength, i.e., in the limit of a hard wall. In the SR case, drying is also critical but the order of the wetting transition depends on the truncation range of the wall-fluid potential. We characterize the approach to critical drying and wetting in terms of the density and local compressibility profiles and via the finite-size scaling properties of the probability distribution of the overall density. For the LR case, where the drying point is known exactly, this analysis allows us to estimate the exponent ν∥, which controls the parallel correlation length, i.e., the extent of vapor bubbles at the wall. Surprisingly, the value we obtain is over twice that predicted by mean field and renormalization group calculations, despite the fact that our three dimensional system is at the upper critical dimension where mean field theory for critical exponents is expected to hold. Possible reasons for this discrepancy are discussed in the light of fresh insights into the nature of near critical finite-size effects.

  20. Drying and wetting transitions of a Lennard-Jones fluid: Simulations and density functional theory.

    PubMed

    Evans, Robert; Stewart, Maria C; Wilding, Nigel B

    2017-07-28

    We report a theoretical and simulation study of the drying and wetting phase transitions of a truncated Lennard-Jones fluid at a flat structureless wall. Binding potential calculations predict that the nature of these transitions depends on whether the wall-fluid attraction has a long ranged (LR) power law decay or is instead truncated, rendering it short ranged (SR). Using grand canonical Monte Carlo simulation and classical density functional theory, we examine both cases in detail. We find that for the LR case wetting is first order, while drying is continuous (critical) and occurs exactly at zero attractive wall strength, i.e., in the limit of a hard wall. In the SR case, drying is also critical but the order of the wetting transition depends on the truncation range of the wall-fluid potential. We characterize the approach to critical drying and wetting in terms of the density and local compressibility profiles and via the finite-size scaling properties of the probability distribution of the overall density. For the LR case, where the drying point is known exactly, this analysis allows us to estimate the exponent ν∥, which controls the parallel correlation length, i.e., the extent of vapor bubbles at the wall. Surprisingly, the value we obtain is over twice that predicted by mean field and renormalization group calculations, despite the fact that our three dimensional system is at the upper critical dimension where mean field theory for critical exponents is expected to hold. Possible reasons for this discrepancy are discussed in the light of fresh insights into the nature of near critical finite-size effects.

  1. Intracytoplasmic and surface-bound immunoglobulins in "nonsecretory" and Bence-Jones myeloma.

    PubMed Central

    Preud'Homme, J L; Hurez, D; Danon, F; Brouet, J C; Seligmann, M

    1976-01-01

    Immunoglobulins were studied at the cellular level by direct immunofluorescence in twenty-five patients with 'nonsecretory' myeloma and thirty-six patiens with Bence-Jones (BJ) myeloma. The results were compared with those obtained in a control group of thirty-six patients with common secretory myeloma. A monoclonal Ig (IgG in eighteen, IgA in three and kappa chains only in three cases) was found in the cytoplasm of the plasma cells from all the patients with 'nonsecretory' myeloma, with a striking dysbalance in the staining brightness for the heavy and the light chains. A similar dysbalance in staining was also observed for plasma cell surface Ig chains but in the opposite way. In twenty patients with BJ myeloma studied for cytoplasmic Ig only, determinants of a heavy chain were clearly found in four cases. When surface Ig were studied also, the production of gamma chains in addition to the light chain could be ascertained in six of sixteen cases. In addition, IgM with the same light chain type as the BJ protein was detected at the cell surface on plasma cells and lymphocytes in two of these sixteen patients. 'Monoclonal' populations of B lymphocytes bearing the same Ig chains as those produced by the myeloma cells were detectable in five of eleven 'nonsecretory' myeloma and in five of sixteen BJ myeloma patients. Normal blood B lymphocytes were in decreased number, particularly when a 'monoclonal' lymphocytic population was detected. Data are discussed which suggest that plasma cells from most patients with 'nonsecretory' myeloma might synthesize and secrete Ig molecules with structurally abnormal chains that are then quickly degraded. PMID:822974

  2. Detecting macroeconomic phases in the Dow Jones Industrial Average time series

    NASA Astrophysics Data System (ADS)

    Wong, Jian Cheng; Lian, Heng; Cheong, Siew Ann

    2009-11-01

    In this paper, we perform statistical segmentation and clustering analysis of the Dow Jones Industrial Average (DJI) time series between January 1997 and August 2008. Modeling the index movements and log-index movements as stationary Gaussian processes, we find a total of 116 and 119 statistically stationary segments respectively. These can then be grouped into between five and seven clusters, each representing a different macroeconomic phase. The macroeconomic phases are distinguished primarily by their volatilities. We find that the US economy, as measured by the DJI, spends most of its time in a low-volatility phase and a high-volatility phase. The former can be roughly associated with economic expansion, while the latter contains the economic contraction phase in the standard economic cycle. Both phases are interrupted by a moderate-volatility market correction phase, but extremely-high-volatility market crashes are found mostly within the high-volatility phase. From the temporal distribution of various phases, we see a high-volatility phase from mid-1998 to mid-2003, and another starting mid-2007 (the current global financial crisis). Transitions from the low-volatility phase to the high-volatility phase are preceded by a series of precursor shocks, whereas the transition from the high-volatility phase to the low-volatility phase is preceded by a series of inverted shocks. The time scale for both types of transitions is about a year. We also identify the July 1997 Asian Financial Crisis to be the trigger for the mid-1998 transition, and an unnamed May 2006 market event related to corrections in the Chinese markets to be the trigger for the mid-2007 transition.

  3. Pressure-induced conformational changes in a human Bence-Jones protein (Mcg).

    PubMed

    Herron, J N; Ely, K R; Edmundson, A B

    1985-07-02

    The effect of high static pressures on the internal structure of the immunoglobulin light chain (Bence-Jones) dimer from the patient Mcg was assessed with measurements of intrinsic protein fluorescence polarization and intensity. Depolarization of intrinsic fluorescence was observed at relatively low pressures (less than 2 kbar), with a standard volume change of -93 mL/mol. The significant conformational changes indicated by these observations were not attributable to major protein unfolding, since pressures exceeding 2 kbar were required to alter intrinsic fluorescence emission maxima and yields. Fluorescence intensity and polarization measurements were used to investigate pressure effects on the binding of bis(8-anilino-naphthalene-1-sulfonate) (bis-ANS), rhodamine 123, and bis(N-methylacridinium nitrate) (lucigenin). Below 1.5 kbar the Mcg dimer exhibited a small decrease in affinity for bis-ANS (standard volume change approximately 5.9 mL/mol). At 3 kbar the binding activity increased by greater than 250-fold (volume change -144 mL/mol) and remained 10-fold higher than its starting value after decompression. With rhodamine 123 the binding activity showed an initial linear increase but plateaued at pressures greater than 1.5 kbar (standard volume change -23 mL/mol). These pressure effects were completely reversible. Binding activity with lucigenin increased slightly at low pressures (standard volume change -5.5 mL/mol), but the protein was partially denatured at pressures greater than 2 kbar. Taken in concert with the results of parallel binding studies in crystals of the Mcg dimer, these observations support the concept of a large malleable binding region with broad specificity for aromatic compounds.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. The impact of surface area, volume, curvature, and Lennard-Jones potential to solvation modeling.

    PubMed

    Nguyen, Duc D; Wei, Guo-Wei

    2017-01-05

    This article explores the impact of surface area, volume, curvature, and Lennard-Jones (LJ) potential on solvation free energy predictions. Rigidity surfaces are utilized to generate robust analytical expressions for maximum, minimum, mean, and Gaussian curvatures of solvent-solute interfaces, and define a generalized Poisson-Boltzmann (GPB) equation with a smooth dielectric profile. Extensive correlation analysis is performed to examine the linear dependence of surface area, surface enclosed volume, maximum curvature, minimum curvature, mean curvature, and Gaussian curvature for solvation modeling. It is found that surface area and surfaces enclosed volumes are highly correlated to each other's, and poorly correlated to various curvatures for six test sets of molecules. Different curvatures are weakly correlated to each other for six test sets of molecules, but are strongly correlated to each other within each test set of molecules. Based on correlation analysis, we construct twenty six nontrivial nonpolar solvation models. Our numerical results reveal that the LJ potential plays a vital role in nonpolar solvation modeling, especially for molecules involving strong van der Waals interactions. It is found that curvatures are at least as important as surface area or surface enclosed volume in nonpolar solvation modeling. In conjugation with the GPB model, various curvature-based nonpolar solvation models are shown to offer some of the best solvation free energy predictions for a wide range of test sets. For example, root mean square errors from a model constituting surface area, volume, mean curvature, and LJ potential are less than 0.42 kcal/mol for all test sets. © 2016 Wiley Periodicals, Inc.

  5. Spontaneous cavitation in a Lennard-Jones liquid at negative pressures.

    PubMed

    Baidakov, V G; Bobrov, K S

    2014-05-14

    We report a molecular dynamics (MD) study of homogeneous bubble nucleation in a Lennard-Jones liquid under a negative pressure (cavitation). The rate of bubble nucleation has been determined in the range 2 x 10(-9) < J(*) = Jσ(4)(m/ε)(1/2) < 6 x 10(-6) by the mean lifetime method at temperatures T(*) = kBT/ε = 0.35, 0.4, 0.5, 0.6, 0.7, 0.8, 0.4, 0.5, 0.6, 0.7, 0.8. In molecular dynamics simulation calculations have also been made of the coefficient of bubble size diffusion, the Zeldovich nonequilibrium factor, and the radius of a critical nucleus R*. Different approaches to the determination of the nucleation rate in a stretched liquid have been considered in the framework of classical nucleation theory (CNT). The values of J obtained in MD simulation are by 8-20 orders higher than those predicted by CNT. The work of formation of a critical bubble and the dependence of surface tension γ(R*) at the critical bubble-liquid interface have been determined by data of MD simulation from CNT. The values of γ obtained have been approximated by an extended Tolman formula that takes into account, besides a linear correction, also the quadratic in curvature terms. The Tolman length δ∞ is negative and equals -(0.1-0.2)σ. The coefficient at 1/R*(2) is positive and does not exceed σ(2).

  6. Crystallization of Lennard-Jones nanodroplets: From near melting to deeply supercooled.

    PubMed

    Malek, Shahrazad M A; Morrow, Gregory P; Saika-Voivod, Ivan

    2015-03-28

    We carry out molecular dynamics (MD) and Monte Carlo (MC) simulations to characterize nucleation in liquid clusters of 600 Lennard-Jones particles over a broad range of temperatures. We use the formalism of mean first-passage times to determine the rate and find that Classical Nucleation Theory (CNT) predicts the rate quite well, even when employing simple modelling of crystallite shape, chemical potential, surface tension, and particle attachment rate, down to the temperature where the droplet loses metastability and crystallization proceeds through growth-limited nucleation in an unequilibrated liquid. Below this crossover temperature, the nucleation rate is still predicted when MC simulations are used to directly calculate quantities required by CNT. Discrepancy in critical embryo sizes obtained from MD and MC arises when twinned structures with five-fold symmetry provide a competing free energy pathway out of the critical region. We find that crystallization begins with hcp-fcc stacked precritical nuclei and differentiation to various end structures occurs when these embryos become critical. We confirm that using the largest embryo in the system as a reaction coordinate is useful in determining the onset of growth-limited nucleation and show that it gives the same free energy barriers as the full cluster size distribution once the proper reference state is identified. We find that the bulk melting temperature controls the rate, even though the solid-liquid coexistence temperature for the droplet is significantly lower. The value of surface tension that renders close agreement between CNT and direct rate determination is significantly lower than what is expected for the bulk system.

  7. Conformation of a flexible polymer in explicit solvent: Accurate solvation potentials for Lennard-Jones chains.

    PubMed

    Taylor, Mark P; Ye, Yuting; Adhikari, Shishir R

    2015-11-28

    The conformation of a polymer chain in solution is coupled to the local structure of the surrounding solvent and can undergo large changes in response to variations in solvent density and temperature. The many-body effects of solvent on the structure of an n-mer polymer chain can be formally mapped to an exact n-body solvation potential. Here, we use a pair decomposition of this n-body potential to construct a set of two-body potentials for a Lennard-Jones (LJ) polymer chain in explicit LJ solvent. The solvation potentials are built from numerically exact results for 5-mer chains in solvent combined with an approximate asymptotic expression for the solvation potential between sites that are distant along the chain backbone. These potentials map the many-body chain-in-solvent problem to a few-body single-chain problem and can be used to study a chain of arbitrary length, thereby dramatically reducing the computational complexity of the polymer chain-in-solvent problem. We have constructed solvation potentials at a large number of state points across the LJ solvent phase diagram including the vapor, liquid, and super-critical regions. We use these solvation potentials in single-chain Monte Carlo (MC) simulations with n ≤ 800 to determine the size, intramolecular structure, and scaling behavior of chains in solvent. To assess our results, we have carried out full chain-in-solvent MC simulations (with n ≤ 100) and find that our solvation potential approach is quantitatively accurate for a wide range of solvent conditions for these chain lengths.

  8. Molecular characterization of Myostatin gene from Zhikong scallop Chlamys farreri (Jones et Preston 1904).

    PubMed

    Hu, Xiaoli; Guo, Huihui; He, Yan; Wang, Shan; Zhang, Lingling; Wang, Shi; Huang, Xiaoting; Roy, Scott William; Lu, Wei; Hu, Jingjie; Bao, Zhenmin

    2010-01-01

    The scallop is an economically important sea food prized for its large and delicious adductor muscle. Studying the molecular basis of scallop muscle growth is important for both scallop breeding and our understanding of muscle mass regulation in bivalve. Myostatin (MSTN) is a conserved negative regulator of muscle growth and development. Here we report the MSTN gene from Zhikong scallop (Chlamys farreri Jones et Preston 1904). The C. farreri MSTN consists of 11651 nucleotides encoding 457 amino acids. The gene has a 3-exon/2-intron structure that is conserved with vertebrate homologs. The exons are 586, 380 and 408 bp in length, respectively, and separated by introns of 5086 and 1518 bp. The protein sequence contains characteristic conserved residues including a cleavage motif of proteolysis (RXXR) and nine cysteines. Three transcription initiation sites were found at 62, 146, and 296 bp upstream of the translation start codon ATG. In silico analysis of the promoter region identified a TATA-box and several muscle-specific regulatory elements including COMP, MEF2s, MTBFs and E-boxes. Minisatellite DNA was found in intron 1. By fluorescence in situ hybridization (FISH), the gene was mapped to the long arm of a pair of middle subtelocentric chromosome. Quantitative analysis of MSTN transcripts in embryos/larvae indicated high expression level in gastrulae and limited expression at other stages. In adult scallops, MSTN is predominantly expressed in striated muscle, with different expression levels in other tissues. Our data provide valuable genomic and expression information which will aid the further study on scallop MSTN function and MSTN evolution.

  9. Proposal to replace the illegitimate genus name Prescottia Jones et al. 2013 with the genus name Prescottella gen. nov. and to replace the illegitimate combination Prescottia equi Jones et al. 2013 with Prescottella equi comb. nov.

    PubMed

    Jones, Amanda L; Sutcliffe, Iain C; Goodfellow, Michael

    2013-06-01

    Recently we proposed that Rhodococcus equi (Magnusson 1923) Goodfellow and Alderson 1977 be transferred to a novel genus, Prescottia, as Prescottia equi comb. nov. However, in accordance with Principle 2 and Rule 51b(4) of the Bacteriological Code (1990 Revision), the bacterial genus name Prescottia Jones et al. 2013 is deemed illegitimate as this name has been used previously for a plant genus within the family Orchidaceae. Consequently, a new genus name, Prescottella gen. nov. is proposed for the bacterial taxon and a new combination Prescottella equi comb. nov. is proposed for the type species.

  10. Liquid-liquid interfacial properties of a symmetrical Lennard-Jones binary mixture

    SciTech Connect

    Martínez-Ruiz, F. J.; Blas, F. J.; Moreno-Ventas Bravo, A. I.

    2015-09-14

    We determine the interfacial properties of a symmetrical binary mixture of equal-sized spherical Lennard-Jones molecules, σ{sub 11} = σ{sub 22}, with the same dispersive energy between like species, ϵ{sub 11} = ϵ{sub 22}, but different dispersive energies between unlike species low enough to induce phase separation. We use the extensions of the improved version of the inhomogeneous long-range corrections of Janecek [J. Phys. Chem. B 110, 6264 (2006)], presented recently by MacDowell and Blas [J. Chem. Phys. 131, 074705 (2009)] and Martínez-Ruiz et al. [J. Chem. Phys. 141, 184701 (2014)], to deal with the interaction energy and microscopic components of the pressure tensor. We perform Monte Carlo simulations in the canonical ensemble to obtain the interfacial properties of the symmetrical mixture with different cut-off distances r{sub c} and in combination with the inhomogeneous long-range corrections. The pressure tensor is obtained using the mechanical (virial) and thermodynamic route. The liquid-liquid interfacial tension is also evaluated using three different procedures, the Irving-Kirkwood method, the difference between the macroscopic components of the pressure tensor, and the test-area methodology. This allows to check the validity of the recent extensions presented to deal with the contributions due to long-range corrections for intermolecular energy and pressure tensor in the case of binary mixtures that exhibit liquid-liquid immiscibility. In addition to the pressure tensor and the surface tension, we also obtain density profiles and coexistence densities and compositions as functions of pressure, at a given temperature. According to our results, the main effect of increasing the cut-off distance r{sub c} is to sharpen the liquid-liquid interface and to increase the width of the biphasic coexistence region. Particularly interesting is the presence of a relative minimum in the total density profiles of the symmetrical mixture. This minimum is related

  11. Point-to-set dynamic length scale in binary Lennard-Jones glass-formers.

    PubMed

    Mei, Baicheng; Wang, Zhenhua; Lu, Yuyuan; Li, Hongfei; An, Lijia

    2017-09-21

    Our recent molecular dynamics simulation results of binary particle glass-former systems demonstrated that the non-monotonic temperature T-dependence of the point-to-set dynamic length scale ξc(dyn) in harmonic (HM) systems is not an intrinsic property of bulk liquids but originates from wall effects. We would expect our results to apply equally to other simple models, such as Lennard-Jones (LJ) systems. However, Hocky et al. presented a monotonic T-dependent ξc(dyn) in a LJ system. Therefore, the present work employs molecular dynamics simulations to investigate the T-dependent behavior of ξc(dyn) in the LJ system employed by Hocky et al. to clarify our expectation. Results employing a geometry size d that is somewhat smaller than that employed by Hocky et al. reveal that a non-monotonic behavior exists in the LJ system. By varying the value of d, we demonstrate that the formation of a peak in ξc(dyn) with respect to T in the LJ system is the natural result of wall effects. More importantly, a new non-monotonic behavior is observed, where the temperature at which the ratio of the characteristic time required for the overlap profile of the system to decay to a given value for a point near the wall to the corresponding characteristic time at a point in the center attains a maximum is in good agreement with the temperature Tmax-c at which ξc(dyn) attains a maximum value, indicating that the non-monotonic behavior of ξc(dyn) with respect to T is a natural property of liquids in a sandwiched geometry. Furthermore, we find that, contrary to HM systems, where the values of Tmax-c obtained for all values of d considered were greater than the mode-coupling temperature Tc, the value of Tmax-c obtained for LJ systems can be either greater than, equal to, or less than Tc because an HM system has a stronger finite-size effect than that in a LJ system, indirectly implying that the conclusion derived from random first-order transition theory that a dramatic change occurs

  12. Generalized coupling parameter expansion: application to square well and Lennard-Jones fluids.

    PubMed

    Sai Venkata Ramana, A

    2013-07-28

    The coupling parameter expansion in thermodynamic perturbation theory of simple fluids is generalized to include the derivatives of bridge function with respect to coupling parameter. We applied seventh order version of the theory to Square-Well (SW) and Lennard-Jones (LJ) fluids using Sarkisov Bridge function. In both cases, the theory reproduced the radial distribution functions obtained from integral equation theory (IET) and simulations with good accuracy. Also, the method worked inside the liquid-vapor coexistence region where the IETs are known to fail. In the case of SW fluids, the use of Carnahan-Starling expression for Helmholtz free energy density of Hard-Sphere reference system has improved the liquid-vapor phase diagram (LVPD) over that obtained from IET with the same bridge function. The derivatives of the bridge function are seen to have significant effect on the liquid part of the LVPD. For extremely narrow SW fluids, we found that the third order theory is more accurate than the higher order versions. However, considering the convergence of the perturbation series, we concluded that the accuracy of the third order version is a spurious result. We also obtained the surface tension for SW fluids of various ranges. Results of present theory and simulations are in good agreement. In the case of LJ fluids, the equation of state obtained from the present method matched with that obtained from IET with negligible deviation. We also obtained LVPD of LJ fluid from virial and energy routes and found that there is slight inconsistency between the two routes. The applications lead to the following conclusions. In cases where reference system properties are known accurately, the present method gives results which are very much improved over those obtained from the IET with the same bridge function. In cases where reference system data is not available, the method serves as an alternative way of solving the Ornstein-Zernike equation with a given closure relation

  13. Liquid-liquid interfacial properties of a symmetrical Lennard-Jones binary mixture

    NASA Astrophysics Data System (ADS)

    Martínez-Ruiz, F. J.; Moreno-Ventas Bravo, A. I.; Blas, F. J.

    2015-09-01

    We determine the interfacial properties of a symmetrical binary mixture of equal-sized spherical Lennard-Jones molecules, σ11 = σ22, with the same dispersive energy between like species, ɛ11 = ɛ22, but different dispersive energies between unlike species low enough to induce phase separation. We use the extensions of the improved version of the inhomogeneous long-range corrections of Janec̆ek [J. Phys. Chem. B 110, 6264 (2006)], presented recently by MacDowell and Blas [J. Chem. Phys. 131, 074705 (2009)] and Martínez-Ruiz et al. [J. Chem. Phys. 141, 184701 (2014)], to deal with the interaction energy and microscopic components of the pressure tensor. We perform Monte Carlo simulations in the canonical ensemble to obtain the interfacial properties of the symmetrical mixture with different cut-off distances rc and in combination with the inhomogeneous long-range corrections. The pressure tensor is obtained using the mechanical (virial) and thermodynamic route. The liquid-liquid interfacial tension is also evaluated using three different procedures, the Irving-Kirkwood method, the difference between the macroscopic components of the pressure tensor, and the test-area methodology. This allows to check the validity of the recent extensions presented to deal with the contributions due to long-range corrections for intermolecular energy and pressure tensor in the case of binary mixtures that exhibit liquid-liquid immiscibility. In addition to the pressure tensor and the surface tension, we also obtain density profiles and coexistence densities and compositions as functions of pressure, at a given temperature. According to our results, the main effect of increasing the cut-off distance rc is to sharpen the liquid-liquid interface and to increase the width of the biphasic coexistence region. Particularly interesting is the presence of a relative minimum in the total density profiles of the symmetrical mixture. This minimum is related with a desorption of the molecules

  14. Properties of Organic Liquids when Simulated with Long-Range Lennard-Jones Interactions.

    PubMed

    Fischer, Nina M; van Maaren, Paul J; Ditz, Jonas C; Yildirim, Ahmet; van der Spoel, David

    2015-07-14

    In order to increase the accuracy of classical computer simulations, existing methodologies may need to be adapted. Hitherto, most force fields employ a truncated potential function to model van der Waals interactions, sometimes augmented with an analytical correction. Although such corrections are accurate for homogeneous systems with a long cutoff, they should not be used in inherently inhomogeneous systems such as biomolecular and interface systems. For such cases, a variant of the particle mesh Ewald algorithm (Lennard-Jones PME) was already proposed 20 years ago (Essmann et al. J. Chem. Phys. 1995, 103, 8577-8593), but it was implemented only recently (Wennberg et al. J. Chem. Theory Comput. 2013, 9, 3527-3537) in a major simulation code (GROMACS). The availability of this method allows surface tensions of liquids as well as bulk properties to be established, such as density and enthalpy of vaporization, without approximations due to truncation. Here, we report on simulations of ≈150 liquids (taken from a force field benchmark: Caleman et al. J. Chem. Theory Comput. 2012, 8, 61-74) using three different force fields and compare simulations with and without explicit long-range van der Waals interactions. We find that the density and enthalpy of vaporization increase for most liquids using the generalized Amber force field (GAFF, Wang et al. J. Comput. Chem. 2004, 25, 1157-1174) and the Charmm generalized force field (CGenFF, Vanommeslaeghe et al. J. Comput. Chem. 2010, 31, 671-690) but less so for OPLS/AA (Jorgensen and Tirado-Rives, Proc. Natl. Acad. Sci. U.S.A. 2005, 102, 6665-6670), which was parametrized with an analytical correction to the van der Waals potential. The surface tension increases by ≈10(-2) N/m for all force fields. These results suggest that van der Waals attractions in force fields are too strong, in particular for the GAFF and CGenFF. In addition to the simulation results, we introduce a new version of a web server, http

  15. Liquid-liquid interfacial properties of a symmetrical Lennard-Jones binary mixture.

    PubMed

    Martínez-Ruiz, F J; Moreno-Ventas Bravo, A I; Blas, F J

    2015-09-14

    We determine the interfacial properties of a symmetrical binary mixture of equal-sized spherical Lennard-Jones molecules, σ11 = σ22, with the same dispersive energy between like species, ϵ11 = ϵ22, but different dispersive energies between unlike species low enough to induce phase separation. We use the extensions of the improved version of the inhomogeneous long-range corrections of Janec̆ek [J. Phys. Chem. B 110, 6264 (2006)], presented recently by MacDowell and Blas [J. Chem. Phys. 131, 074705 (2009)] and Martínez-Ruiz et al. [J. Chem. Phys. 141, 184701 (2014)], to deal with the interaction energy and microscopic components of the pressure tensor. We perform Monte Carlo simulations in the canonical ensemble to obtain the interfacial properties of the symmetrical mixture with different cut-off distances rc and in combination with the inhomogeneous long-range corrections. The pressure tensor is obtained using the mechanical (virial) and thermodynamic route. The liquid-liquid interfacial tension is also evaluated using three different procedures, the Irving-Kirkwood method, the difference between the macroscopic components of the pressure tensor, and the test-area methodology. This allows to check the validity of the recent extensions presented to deal with the contributions due to long-range corrections for intermolecular energy and pressure tensor in the case of binary mixtures that exhibit liquid-liquid immiscibility. In addition to the pressure tensor and the surface tension, we also obtain density profiles and coexistence densities and compositions as functions of pressure, at a given temperature. According to our results, the main effect of increasing the cut-off distance rc is to sharpen the liquid-liquid interface and to increase the width of the biphasic coexistence region. Particularly interesting is the presence of a relative minimum in the total density profiles of the symmetrical mixture. This minimum is related with a desorption of the molecules

  16. Effect of molecular flexibility of Lennard-Jones chains on vapor-liquid interfacial properties.

    PubMed

    Blas, F J; Moreno-Ventas Bravo, A I; Algaba, J; Martínez-Ruiz, F J; MacDowell, L G

    2014-03-21

    We have determined the interfacial properties of short fully flexible chains formed from tangentially bonded Lennard-Jones monomeric units from direct simulation of the vapor-liquid interface. The results obtained are compared with those corresponding to rigid-linear chains formed from the same chain length, previously determined in the literature [F. J. Blas, A. I. M.-V. Bravo, J. M. Míguez, M. M. Piñeiro, and L. G. MacDowell, J. Chem. Phys. 137, 084706 (2012)]. The full long-range tails of the potential are accounted for by means of an improved version of the inhomogeneous long-range corrections of Janeček [J. Phys. Chem. B 129, 6264 (2006)] proposed recently by MacDowell and Blas [J. Chem. Phys. 131, 074705 (2008)] valid for spherical as well as for rigid and flexible molecular systems. Three different model systems comprising of 3, 5, and 6 monomers per molecule are considered. The simulations are performed in the canonical ensemble, and the vapor-liquid interfacial tension is evaluated using the test-area method. In addition to the surface tension, we also obtained density profiles, coexistence densities, critical temperature and density, and interfacial thickness as functions of temperature, paying particular attention to the effect of the chain length and rigidity on these properties. According to our results, the main effect of increasing the chain length (at fixed temperature) is to sharpen the vapor-liquid interface and to increase the width of the biphasic coexistence region. As a result, the interfacial thickness decreases and the surface tension increases as the molecular chains get longer. Comparison between predictions for fully flexible and rigid-linear chains, formed by the same number of monomeric units, indicates that the main effects of increasing the flexibility, i.e., passing from a rigid-linear to a fully flexible chain, are: (a) to decrease the difference between the liquid and vapor densities; (b) to decrease the critical temperature and

  17. A molecular simulation study of freezing/melting phenomena for Lennard-Jones methane in cylindrical nanoscale pores

    NASA Astrophysics Data System (ADS)

    Maddox, M. W.; Gubbins, K. E.

    1997-12-01

    A combination of grand canonical Monte Carlo and molecular dynamics simulation techniques are used to study the freezing and melting of Lennard-Jones methane in several different cylindrical pores. Two different types of pore wall are considered; a strongly attractive wall, and a weakly attractive wall, each with pore diameters in the range 1.5-3.5 nm. Freezing point depression is observed in the case of the weakly attractive pores, in agreement with several experimental studies. Freezing point elevation is observed at the walls of the strongly attractive pore, but freezing point depression occurs at the center of such pores, due to geometrical constraints.

  18. Test of classical nucleation theory and mean first-passage time formalism on crystallization in the Lennard-Jones liquid

    SciTech Connect

    Lundrigan, Sarah E. M.; Saika-Voivod, Ivan

    2009-09-14

    We perform molecular dynamics (MD) and Monte Carlo computer simulations to test the ability of the recently developed formalism of mean first-passage time (MFPT) [J. Wedekind, R. Strey, and D. Reguera, J. Chem. Phys. 126, 134103 (2007); J. Wedekind and D. Reguera, J. Phys. Chem. B 112, 11060 (2008)] to characterize crystal nucleation in the Lennard-Jones liquid. We find that the nucleation rate, critical embryo size, Zeldovich factor, attachment rate, and the nucleation barrier profile obtained from MFPT all compare very well to the same quantities calculated using other methods. Furthermore, we find that the nucleation rate obtained directly through MD closely matches the prediction of classical nucleation theory.

  19. Super-Arrhenius diffusion in an undercooled binary Lennard-Jones liquid results from a quantifiable correlation effect.

    PubMed

    de Souza, Vanessa K; Wales, David J

    2006-02-10

    On short time scales an underlying Arrhenius temperature dependence of the diffusion constant can be extracted from the fragile, super-Arrhenius diffusion of a binary Lennard-Jones mixture. This Arrhenius diffusion is related to the true super-Arrhenius behavior by a factor that depends on the average angle between steps in successive time windows. The correction factor accounts for the fact that on average, successive displacements are negatively correlated, and this effect can therefore be linked directly with the higher apparent activation energy for diffusion at low temperature.

  20. Formation of regular polyicosahedral structure during growth of large Lennard-Jones clusters from their global minimum

    NASA Astrophysics Data System (ADS)

    Polak, Wiesław Z.

    2016-08-01

    Simulated growth of four global-minimum Lennard-Jones clusters of sizes N = 561, 823, 850 and 923, representing multishell icosahedra and decahedron, always leads to formation of regular polyicosahedral clusters. Observation of cluster structure evolution revealed that new atoms form anti-Mackay islands spreading over the cluster surface by making strong island-island junctions at cluster edges. Analysis of potential energies of atoms composing different local structures shows that energy-driven preference for decahedral arrangement of several atoms initiating the junction of pentagonal symmetry on the cluster surface is responsible for kinetic effect in the cluster growth.

  1. A transferable coarse-grained potential to study the structure of confined, supercritical Lennard-Jones fluids.

    PubMed

    Sanghi, T; Aluru, N R

    2010-01-28

    In this paper, we develop a transferable coarse-grained interatomic potential to study the structure of simple (spherical and nonpolar) Lennard-Jones (LJ) fluids confined at supercritical temperatures. The potential is used in empirical potential based quasicontinuum theory, [A. V. Raghunathan et al., J. Chem. Phys. 127, 174701 (2007)] to study the structure of three simple LJ fluids (oxygen, methane, and argon) confined in slitlike geometries. The results obtained using the coarse-grained interatomic potential are found to be in good agreement with those predicted by equilibrium molecular dynamics simulations.

  2. Test of classical nucleation theory and mean first-passage time formalism on crystallization in the Lennard-Jones liquid

    NASA Astrophysics Data System (ADS)

    Lundrigan, Sarah E. M.; Saika-Voivod, Ivan

    2009-09-01

    We perform molecular dynamics (MD) and Monte Carlo computer simulations to test the ability of the recently developed formalism of mean first-passage time (MFPT) [J. Wedekind, R. Strey, and D. Reguera, J. Chem. Phys. 126, 134103 (2007); J. Wedekind and D. Reguera, J. Phys. Chem. B 112, 11060 (2008)] to characterize crystal nucleation in the Lennard-Jones liquid. We find that the nucleation rate, critical embryo size, Zeldovich factor, attachment rate, and the nucleation barrier profile obtained from MFPT all compare very well to the same quantities calculated using other methods. Furthermore, we find that the nucleation rate obtained directly through MD closely matches the prediction of classical nucleation theory.

  3. STS-132 ascent flight control team photo with Flight Director Richard Jones and the STS-132 crew

    NASA Image and Video Library

    2010-06-08

    JSC2010-E-090665 (8 June 2010) --- The members of the STS-132 Ascent flight control team and crew members pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Richard Jones (right) and NASA astronaut Ken Ham, STS-132 commander, hold the STS-132 mission logo. Additional crew members pictured are NASA astronauts Tony Antonelli, pilot; along with Garrett Reisman, Piers Sellers, Michael Good and Steve Bowen, all mission specialists. Photo credit: NASA or National Aeronautics and Space Administration

  4. Effect of gold nanoparticles on structure and dynamics of binary Lennard-Jones liquid: Direct space analysis

    NASA Astrophysics Data System (ADS)

    Separdar, L.; Davatolhagh, S.

    2013-02-01

    We investigate the static structure and diffusive dynamics of binary Lennard-Jones mixture upon supercooling in the presence of gold nanoparticle within the framework of the mode-coupling theory of the dynamic glass transition in the direct space by means of constant-NVT molecular dynamics simulations. It is found that the presence of gold nanoparticle causes the energy per particle and the pressure of this system to decrease with respect to the bulk binary Lennard-Jones mixture. Furthermore, the presence of nanoparticle has a direct effect on the liquid structure and causes the peaks of the radial distribution functions to become shorter with respect to the bulk binary Lennard-Jones liquid. The dynamics of the liquid at a given density is found to be consistent with the mode-coupling theory (MCT) predictions in a certain range at low temperatures. In accordance with the idealized MCT, the diffusion constants D(T) show a power-law behavior at low temperatures for both types of binary Lennard-Jones (BLJ) particles as well as the gold atoms comprising the nanoparticle. The mode-coupling crossover temperature Tc is the same for all particle types; however, Tc=0.4 is reduced with respect to that of the bulk BLJ liquid, and the γ exponent is found to depend on the particle type. The existence of the nanoparticle causes the short-time β-relaxation regime to shorten and the range of validity of the MCT shrinks with respect to the bulk BLJ. It is also found that at intermediate and low temperatures the curves of the mean-squared displacements (MSDs) versus tD(T) fall onto a master curve. The MSDs follow the master curve in an identical time range with the long-time α-relaxation regime of the mode-coupling theory. By obtaining the viscosity, it is observed that the Stokes-Einstein relation remains valid at high and intermediate temperatures but breaks down as the temperatures approach Tc as a result of the cooperative motion or activated processes.

  5. Effect of gold nanoparticles on structure and dynamics of binary Lennard-Jones liquid: direct space analysis.

    PubMed

    Separdar, L; Davatolhagh, S

    2013-02-01

    We investigate the static structure and diffusive dynamics of binary Lennard-Jones mixture upon supercooling in the presence of gold nanoparticle within the framework of the mode-coupling theory of the dynamic glass transition in the direct space by means of constant-NVT molecular dynamics simulations. It is found that the presence of gold nanoparticle causes the energy per particle and the pressure of this system to decrease with respect to the bulk binary Lennard-Jones mixture. Furthermore, the presence of nanoparticle has a direct effect on the liquid structure and causes the peaks of the radial distribution functions to become shorter with respect to the bulk binary Lennard-Jones liquid. The dynamics of the liquid at a given density is found to be consistent with the mode-coupling theory (MCT) predictions in a certain range at low temperatures. In accordance with the idealized MCT, the diffusion constants D(T) show a power-law behavior at low temperatures for both types of binary Lennard-Jones (BLJ) particles as well as the gold atoms comprising the nanoparticle. The mode-coupling crossover temperature T(c) is the same for all particle types; however, T(c)=0.4 is reduced with respect to that of the bulk BLJ liquid, and the γ exponent is found to depend on the particle type. The existence of the nanoparticle causes the short-time β-relaxation regime to shorten and the range of validity of the MCT shrinks with respect to the bulk BLJ. It is also found that at intermediate and low temperatures the curves of the mean-squared displacements (MSDs) versus tD(T) fall onto a master curve. The MSDs follow the master curve in an identical time range with the long-time α-relaxation regime of the mode-coupling theory. By obtaining the viscosity, it is observed that the Stokes-Einstein relation remains valid at high and intermediate temperatures but breaks down as the temperatures approach T(c) as a result of the cooperative motion or activated processes.

  6. Bulk viscosity of the Lennard-Jones system at the triple point by dynamical nonequilibrium molecular dynamics.

    PubMed

    Palla, Pier Luca; Pierleoni, Carlo; Ciccotti, Giovanni

    2008-08-01

    Nonequilibrium molecular dynamics (NEMD) calculations of the bulk viscosity of the triple point Lennard-Jones fluid are performed with the aim of investigating the origin of the observed disagreement between Green-Kubo estimates and previous NEMD data. We show that a careful application of the Doll's perturbation field, the dynamical NEMD method, the instantaneous form of the perturbation and the "subtraction technique" provides a NEMD estimate of the bulk viscosity at zero field in full agreement with the value obtained by the Green-Kubo formula. As previously reported for the shear viscosity, we find that the bulk viscosity exhibits a large linear regime with the field intensity.

  7. The excess thermodynamic functions of three-component Lennard-Jones systems based on binary distribution functions

    NASA Astrophysics Data System (ADS)

    Tarzimanov, A. A.; Klinov, A. V.; Malygin, A. V.; Nurgalieva, A. A.

    2008-08-01

    Integral equation theory was used to study the binary distribution functions of the excess properties of three-component Lennard-Jones mixtures. The results obtained for the behavior of the excess functions of caloric properties (internal energy, enthalpy, and isochoric heat capacity) are reported. The influence of the third component with various potential parameters on excess functions was studied. Calculations were performed for systems under super-and subcritical conditions with different sizes of molecules, σ1/σ2 = 1 4, and attraction energies between them, ɛ1/ɛ2 = 1 4. The results were compared with numerical experiment data to find that the approach used was fairly accurate

  8. High-accuracy calculations of sixteen collision integrals for Lennard-Jones (12–6) gases and their interpolation to parameterize neon, argon, and krypton

    SciTech Connect

    Kim, Sun Ung; Monroe, Charles W.

    2014-09-15

    The inverse problem of parameterizing intermolecular potentials given macroscopic transport and thermodynamic data is addressed. Procedures are developed to create arbitrary-precision algorithms for transport collision integrals, using the Lennard-Jones (12–6) potential as an example. Interpolation formulas are produced that compute these collision integrals to four-digit accuracy over the reduced-temperature range 0.3≤T{sup ⁎}≤400, allowing very fast computation. Lennard-Jones parameters for neon, argon, and krypton are determined by simultaneously fitting the observed temperature dependences of their viscosities and second virial coefficients—one of the first times that a thermodynamic and a dynamic property have been used simultaneously for Lennard-Jones parameterization. In addition to matching viscosities and second virial coefficients within the bounds of experimental error, the determined Lennard-Jones parameters are also found to predict the thermal conductivity and self-diffusion coefficient accurately, supporting the value of the Lennard-Jones (12–6) potential for noble-gas transport-property correlation.

  9. High-accuracy calculations of sixteen collision integrals for Lennard-Jones (12-6) gases and their interpolation to parameterize neon, argon, and krypton

    NASA Astrophysics Data System (ADS)

    Kim, Sun Ung; Monroe, Charles W.

    2014-09-01

    The inverse problem of parameterizing intermolecular potentials given macroscopic transport and thermodynamic data is addressed. Procedures are developed to create arbitrary-precision algorithms for transport collision integrals, using the Lennard-Jones (12-6) potential as an example. Interpolation formulas are produced that compute these collision integrals to four-digit accuracy over the reduced-temperature range 0.3≤T*≤400, allowing very fast computation. Lennard-Jones parameters for neon, argon, and krypton are determined by simultaneously fitting the observed temperature dependences of their viscosities and second virial coefficients-one of the first times that a thermodynamic and a dynamic property have been used simultaneously for Lennard-Jones parameterization. In addition to matching viscosities and second virial coefficients within the bounds of experimental error, the determined Lennard-Jones parameters are also found to predict the thermal conductivity and self-diffusion coefficient accurately, supporting the value of the Lennard-Jones (12-6) potential for noble-gas transport-property correlation.

  10. Point-to-set dynamic length scale in binary Lennard-Jones glass-formers

    NASA Astrophysics Data System (ADS)

    Mei, Baicheng; Wang, Zhenhua; Lu, Yuyuan; Li, Hongfei; An, Lijia

    2017-09-01

    Our recent molecular dynamics simulation results of binary particle glass-former systems demonstrated that the non-monotonic temperature T-dependence of the point-to-set dynamic length scale ξcd y n in harmonic (HM) systems is not an intrinsic property of bulk liquids but originates from wall effects. We would expect our results to apply equally to other simple models, such as Lennard-Jones (LJ) systems. However, Hocky et al. presented a monotonic T-dependent ξcd y n in a LJ system. Therefore, the present work employs molecular dynamics simulations to investigate the T-dependent behavior of ξcd y n in the LJ system employed by Hocky et al. to clarify our expectation. Results employing a geometry size d that is somewhat smaller than that employed by Hocky et al. reveal that a non-monotonic behavior exists in the LJ system. By varying the value of d, we demonstrate that the formation of a peak in ξcd y n with respect to T in the LJ system is the natural result of wall effects. More importantly, a new non-monotonic behavior is observed, where the temperature at which the ratio of the characteristic time required for the overlap profile of the system to decay to a given value for a point near the wall to the corresponding characteristic time at a point in the center attains a maximum is in good agreement with the temperature Tmax-c at which ξcd y n attains a maximum value, indicating that the non-monotonic behavior of ξcd y n with respect to T is a natural property of liquids in a sandwiched geometry. Furthermore, we find that, contrary to HM systems, where the values of Tmax-c obtained for all

  11. Explicit expression for the Stokes-Einstein relation for pure Lennard-Jones liquids.

    PubMed

    Ohtori, Norikazu; Ishii, Yoshiki

    2015-01-01

    An explicit expression of the Stokes-Einstein (SE) relation in molecular scale has been determined for pure Lennard-Jones (LJ) liquids on the saturated vapor line using a molecular dynamics calculation with the Green-Kubo formula, as Dη(sv)=kTξ(-1)(N/V)(1/3), where D is the self-diffusion coefficient, η(sv) the shear viscosity, k the Boltzmann constant, T the temperature, ξ the constant, and N the particle number included in the system volume V. To this end, the dependence of D and η(sv) on packing fraction, η, and T has been determined so as to complete their scaling equations. The equations for D and η(sv) in these states are m(-1/2)(N/V)(-1/3)(1-η)(4)ε(-1/2)T and m(1/2)(N/V)(2/3)(1-η)(-4)ε(1/2)T(0), respectively, where m and ε are the atomic mass and characteristic parameter of energy used in the LJ potentials, respectively. The equations can well describe the behaviors of D and η(sv) for both the LJ and the real rare-gas liquids. The obtained SE relation justifies the theoretical equation proposed by Eyring and Ree, although the value of ξ is slightly different from that given by them. The difference of the obtained expression from the original SE relation, Dη(sv)=(kT/2π)σ(-1), where σ means the particle size, is the presence of the η(1/3) term, since (N/V)(1/3)=(6/π)(1/3)σ(-1)η(1/3). Since the original SE relation is based on the fluid mechanics for continuum media, allowing the presence of voids in liquids is the origin of the η(1/3) term. Therefore, also from this viewpoint, the present expression is more justifiable in molecular scale than the original SE relation. As a result, the η(1/3) term cancels out the σ dependence from the original SE relation. The present result clearly shows that it is not necessary to attribute the deviation from the original SE relation to any temperature dependence of particle size or to introduce the fractional SE relation for pure LJ liquids. It turned out that the η dependence of both D and

  12. Massively parallel dual control volume grand canonical molecular dynamics with LADERA I. Gradient driven diffusion in Lennard-Jones fluids

    NASA Astrophysics Data System (ADS)

    Heffelfinger David, Grant S.; Ford, M.

    A new algorithm to enable the implementation of dual control volume grand canonical molecular dynamics (DCV-GCMD) on massively parallel (MP) architectures is presented. DCVGCMD can be thought of as hybridization of molecular dynamics (MD) and grand canonical Monte Carlo (GCMC) and was developed recently to make possible the simulation of gradient-driven diffusion. The method has broad application to such problems as membrane separations, drug delivery systems, diffusion in polymers and zeolites, etc. The massively parallel algorithm for the DCV-GCMD method has been implemented in a code named LADERA which employs the short range Lennard-Jones potential for pure fluids and multicomponent mixtures including bulk and confined (single pore as well as amorphous solid materials) systems. Like DCV-GCMD, LADERA's MP algorithm can be thought of as a hybridization of two different algorithms, spatial MD and spatial GCMC. The DCV-GCMD method is described fully followed by the DCV-GCMD parallel algorithm employed in LADERA. The scaling characteristics of the new MP algorithm are presented together with the results of the application of LADERA to ternary and quaternary Lennard-Jones mixtures.

  13. Scaling of the viscosity of the Lennard-Jones chain fluid model, argon, and some normal alkanes.

    PubMed

    Galliero, Guillaume; Boned, Christian; Fernández, Josefa

    2011-02-14

    In this work, we have tested the efficiency of two scaling approaches aiming at relating shear viscosity to a single thermodynamic quantity in dense fluids, namely the excess entropy and the thermodynamic scaling methods. Using accurate databases, we have applied these approaches first to a model fluid, the flexible Lennard-Jones chain fluid (from the monomer to the hexadecamer), then to real fluids, such as argon and normal alkanes. To enlarge noticeably the range of thermodynamics conditions for which these scaling methods are applicable, we have shown that the use of the residual viscosity instead of the total viscosity is preferable in the scaling procedures. It has been found that both approaches, using the adequate scaling, are suitable for the Lennard-Jones chain fluid model for a wide range of thermodynamic conditions whatever the chain length when scaling law exponents and prefactors are adjusted for each chain length. Furthermore, these results were found to be well respected by the corresponding real fluids.

  14. Flory-Huggins parameter χ, from binary mixtures of Lennard-Jones particles to block copolymer melts

    NASA Astrophysics Data System (ADS)

    Chremos, Alexandros; Nikoubashman, Arash; Panagiotopoulos, Athanassios Z.

    2014-02-01

    In this contribution, we develop a coarse-graining methodology for mapping specific block copolymer systems to bead-spring particle-based models. We map the constituent Kuhn segments to Lennard-Jones particles, and establish a semi-empirical correlation between the experimentally determined Flory-Huggins parameter χ and the interaction of the model potential. For these purposes, we have performed an extensive set of isobaric-isothermal Monte Carlo simulations of binary mixtures of Lennard-Jones particles with the same size but with asymmetric energetic parameters. The phase behavior of these monomeric mixtures is then extended to chains with finite sizes through theoretical considerations. Such a top-down coarse-graining approach is important from a computational point of view, since many characteristic features of block copolymer systems are on time and length scales which are still inaccessible through fully atomistic simulations. We demonstrate the applicability of our method for generating parameters by reproducing the morphology diagram of a specific diblock copolymer, namely, poly(styrene-b-methyl methacrylate), which has been extensively studied in experiments.

  15. Flory-Huggins parameter χ, from binary mixtures of Lennard-Jones particles to block copolymer melts

    SciTech Connect

    Chremos, Alexandros; Nikoubashman, Arash Panagiotopoulos, Athanassios Z.

    2014-02-07

    In this contribution, we develop a coarse-graining methodology for mapping specific block copolymer systems to bead-spring particle-based models. We map the constituent Kuhn segments to Lennard-Jones particles, and establish a semi-empirical correlation between the experimentally determined Flory-Huggins parameter χ and the interaction of the model potential. For these purposes, we have performed an extensive set of isobaric–isothermal Monte Carlo simulations of binary mixtures of Lennard-Jones particles with the same size but with asymmetric energetic parameters. The phase behavior of these monomeric mixtures is then extended to chains with finite sizes through theoretical considerations. Such a top-down coarse-graining approach is important from a computational point of view, since many characteristic features of block copolymer systems are on time and length scales which are still inaccessible through fully atomistic simulations. We demonstrate the applicability of our method for generating parameters by reproducing the morphology diagram of a specific diblock copolymer, namely, poly(styrene-b-methyl methacrylate), which has been extensively studied in experiments.

  16. Local shear viscosity of strongly inhomogeneous dense fluids: from the hard-sphere to the Lennard-Jones fluids.

    PubMed

    Hoang, Hai; Galliero, Guillaume

    2013-12-04

    This work aims at providing a tractable approach to model the local shear viscosity of strongly inhomogeneous dense fluids composed of spherical molecules, in which the density variations occur on molecular distance. The proposed scheme, which relies on the local density average model, has been applied to the quasi-hard-sphere, the Week-Chandler-Andersen and the Lennard-Jones fluids. A weight function has been developed to deal with the hard-sphere fluid given the specificities of momentum exchange. To extend the approach to the smoothly repulsive potential, we have taken into account that the non-local contributions to the viscosity due to the interactions of particles separated by a given distance are temperature dependent. Then, using a simple perturbation scheme, the approach is extended to the Lennard-Jones fluids. It is shown that the viscosity profiles of inhomogeneous dense fluids deduced from this approach are consistent with those directly computed by non-equilibrium molecular dynamics simulations.

  17. Interatomic Lennard-Jones potentials of linear and branched alkanes calibrated by Gibbs ensemble simulations for vapor-liquid equilibria

    NASA Astrophysics Data System (ADS)

    Chang, Jaeeon; Sandler, Stanley I.

    2004-10-01

    We propose Lennard-Jones potential parameters for interatomic interactions of linear and branched alkanes based on matching the results of Gibbs ensemble simulations of vapor-liquid equilibria to experimental data. The alkane model is similar as in the OPLS-AA [W. L. Jorgensen, D. S. Maxwell, and J. Tirado-Rives, J. Am. Chem. Soc. 118, 11225 (1996)], but multiple atom types for carbon based on the number of covalently bonded hydrogen atoms are necessary to accurately reproduce liquid densities and enthalpies of vaporization with the errors of 2.1% and 3.3%, respectively, for hydrocarbons of various chain lengths and structures. We find that the attraction energies of the carbon atoms are almost proportional to the number of covalent hydrogen atoms with each increasing the carbon energy parameter by ≈0.033 kcal/mol. Though the present force field outperforms the OPLS-AA force field for alkanes we studied, systematic deviations for vapor pressures are still observed with errors of 15%-30%, and critical temperatures are slightly underestimated. We think that these shortcomings are probably due to the inadequacy of the two-parameter Lennard-Jones potential, and especially its behavior at short distances.

  18. Determination of the solid-fluid coexistence of the n - 6 Lennard-Jones system from free energy calculations.

    PubMed

    Sousa, J M G; Ferreira, A L; Barroso, M A

    2012-05-07

    The solid-fluid coexistence properties of the n - 6 Lennard-Jones system, n from 7 to 12, are reported. The procedure relies on determining Helmholtz free energy curves as a function of volume for each phase independently, from several NVT simulations, and then connecting it to points of known absolute free energy. For n = 12 this requires connecting the simulated points to states of very low densities on the liquid phase, and to a harmonic crystal for the solid phase, which involves many extra simulations for each temperature. For the reference points of the remaining systems, however, the free energy at a given density and temperature can be calculated relative to the n = 12 system. The method presented here involves a generalization of the multiple histogram method to combine simulations performed with different potentials, provided they visit overlapping regions of the phase space, and allows for a precise calculation of relative free energies. The densities, free energies, average potential energies, pressure, and chemical potential at coexistence are presented for up to T∗ = 5.0 and new estimations of the triple points are given for the n - 6 Lennard-Jones system.

  19. Flory-Huggins parameter χ, from binary mixtures of Lennard-Jones particles to block copolymer melts.

    PubMed

    Chremos, Alexandros; Nikoubashman, Arash; Panagiotopoulos, Athanassios Z

    2014-02-07

    In this contribution, we develop a coarse-graining methodology for mapping specific block copolymer systems to bead-spring particle-based models. We map the constituent Kuhn segments to Lennard-Jones particles, and establish a semi-empirical correlation between the experimentally determined Flory-Huggins parameter χ and the interaction of the model potential. For these purposes, we have performed an extensive set of isobaric-isothermal Monte Carlo simulations of binary mixtures of Lennard-Jones particles with the same size but with asymmetric energetic parameters. The phase behavior of these monomeric mixtures is then extended to chains with finite sizes through theoretical considerations. Such a top-down coarse-graining approach is important from a computational point of view, since many characteristic features of block copolymer systems are on time and length scales which are still inaccessible through fully atomistic simulations. We demonstrate the applicability of our method for generating parameters by reproducing the morphology diagram of a specific diblock copolymer, namely, poly(styrene-b-methyl methacrylate), which has been extensively studied in experiments.

  20. Temperature and composition dependence of the Soret coefficient in Lennard-Jones mixtures presenting evaporation/condensation phase transition.

    PubMed

    Leonardi, Erminia; D'Aguanno, Bruno; Angeli, Celestino

    2011-03-21

    The thermodiffusive behavior of a Lennard-Jones binary mixture has been studied by using nonequilibrium molecular dynamics. In particular, the dependence of the Soret coefficient, S(T), on the temperature and composition has been investigated, exploring a wide range of temperatures from 1000 K to the condensation temperature of the mixture. In a previous paper the dependence of S(T) on the temperature and the composition was studied for Lennard-Jones binary mixtures presenting mixing/demixing (consolute) phase transition, and the results allowed the formulation of a very simple expression with the computed values of S(T) in the one phase region outside the critical region closely fitted by the function [T - T(c)(x(1))](-1), with T(c)(x(1)) the demixing temperature of the mixture under study. The results of the present work show that the same expression of S(T) can be found for the one phase region outside the evaporation/condensation region but now with T(c) representing the condensation temperature of the mixture under study.