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Sample records for energie aus der

  1. Vollautomatische Segmentierung der Prostata aus 3D-Ultraschallbildern

    NASA Astrophysics Data System (ADS)

    Heimann, Tobias; Simpfendörfer, Tobias; Baumhauer, Matthias; Meinzer, Hans-Peter

    Diese Arbeit beschreibt ein modellbasiertes Verfahren zur Segmentierung der Prostata aus 3D-Ultraschalldaten. Kern der Methode ist ein statistisches Formmodell, das auf Beispieldaten der Prostata trainiert wird. Erster Schritt der Segmentierung ist ein evolutionärer Algorithmus, mit dem das Modell grob im zu segmentierenden Bild positioniert wird. Für die darauf folgende lokale Suche wurden mehrere Varianten des Algorithmus evaluiert, unter anderem Ausreißer-Unterdrückung, freie Deformation und Gewichtung der verwendeten Erscheinungsmodelle nach ihrer Zuverlässigkeit. Alle Varianten wurden auf 35 Ultraschallbildern getestet und mit manuellen Referenzsegmentierungen verglichen. Die beste Variante erreichte eine durchschnittliche Oberflächenabweichung von 1.1 mm.

  2. Reisen im freien Fall - Teil 2: Das Zwillingsparadoxon aus dem Blickwinkel der ART

    NASA Astrophysics Data System (ADS)

    Sonne, Bernd; Weiß, Reinhard

    2013-07-01

    Nachdem wir uns mit den Prinzipien der ART und einigen Beispielen vertraut gemacht haben, kommen wir nun zur Berechnung des Zwillingsparadoxons aus Sicht des reisenden Zwillings. Dabei spielt das Äquivalenzprinzip eine große Rolle. Deshalb wird die Bewegungssituation noch einmal erläutert, diesmal aus Sicht von Katrin. Sie befindet sich in ihrem System S'in Ruhe. In ihrem System läuft die Zeit t'ab. Nach dem Start fühlt Katrin jedoch eine Kraft, die sie als Gravitationskraft interpretieren kann. Sie merkt es daran, dass sie in den Sitz gedrückt wird. Nach einiger Zeit werden die Triebwerke abgeschaltet, und das Raumschiff fliegt mit konstanter Geschwindigkeit weiter, Phase 2. Anschließend wird der Schub der Triebwerke solange umgekehrt, bis das Raumschiff irgendwo mit der Geschwindigkeit null am Umkehrpunkt U landet, Phase 3 (Abb. 15.1). Die Erde, auf der sich Michael befindet, bewegt sich mit x'(t') aus Sicht von Katrin im freien Fall von ihr weg, s. das Experiment mit dem steigenden Fahrstuhl in Abschn. 13.2.1.

  3. Die Anfaenge der Melker Bibliothek - Neue Erkenntnisse zu Handschriften und Fragmenten aus der Zeit vor 1200

    NASA Astrophysics Data System (ADS)

    Glaßner, Christine; Haidinger, Alois

    1996-04-01

    Untersuchung der zeitnahen Eintragungen in diese Handschrift gelang es, die Tätigkeit von zumindest drei wichtigen, im 12. Jahrhundert in Melk identifizierbaren, namentlich nicht bekannten Schreibern chronologisch zuzuordnen. Erstmals wurden die nur fragmentarisch als Makulatur in den Bucheinbänden erhaltenen Handschriften in die Untersuchung einbezogen, so dass für die Wende vom 12. zum 13. Jahrhundert ein Bücherbestand von 68 Handschriften erschlossen werden konnte. Besonders hervorzuheben ist, dass in der Sonderausstellung von 1996 und im Begleitband erstmals eingehend die Bedeutung der ältesten Melker Handschrift, Cod. 412 aus dem frühen 9. Jahrhundert mit naturwissenschaftlichen Texten des Beda Venerabilis, als Vorlage für drei weitere Handschriften diente: Vatikan, Cod. Vat. lat. 643, abgeschrieben wahrscheinlich in Melk, davon abhängig Zwettl, Cod. 296, und Klosterneuburg, Cod. 685. Die Abschriften der Melker Beda-Handschrift sind inhaltlich fast identisch, allerdings um den im Mittelalter fälschlicherweise Beda Venerabilis zugeschriebenen Sternbilderkatalog erweitert.

  4. Das Lektin aus der Erbse Pisum sativum : Bindungsstudien, Monomer-Dimer-Gleichgewicht und Rückfaltung aus Fragmenten

    NASA Astrophysics Data System (ADS)

    Küster, Frank

    2002-11-01

    Das Lektin aus Pisum sativum, der Gartenerbse, ist Teil der Familie der Leguminosenlektine. Diese Proteine haben untereinander eine hohe Sequenzhomologie, und die Struktur ihrer Monomere, ein all-ß-Motiv, ist hoch konserviert. Dagegen gibt es innerhalb der Familie eine große Vielfalt an unterschiedlichen Quartärstrukturen, die Gegenstand kristallographischer und theoretischer Arbeiten waren. Das Erbsenlektin ist ein dimeres Leguminosenlektin mit einer Besonderheit in seiner Struktur: Nach der Faltung in der Zelle wird aus einem Loop eine kurze Aminosäuresequenz herausgeschnitten, so dass sich in jeder Untereinheit zwei unabhängige Polypeptidketten befinden. Beide Ketten sind aber stark miteinander verschränkt und bilden eine gemeinsame strukturelle Domäne. Wie alle Lektine bindet Erbsenlektin komplexe Oligosaccharide, doch sind seine physiologische Rolle und der natürliche Ligand unbekannt. In dieser Arbeit wurden Versuche zur Entwicklung eines Funktionstests für Erbsenlektin durchgeführt und seine Faltung, Stabilität und Monomer-Dimer-Gleichgewicht charakterisiert. Um die spezifische Rolle der Prozessierung für Stabilität und Faltung zu untersuchen, wurde ein unprozessiertes Konstrukt in E. coli exprimiert und mit der prozessierten Form verglichen. Beide Proteine zeigen die gleiche kinetische Stabilität gegenüber chemischer Denaturierung. Sie denaturieren extrem langsam, weil nur die isolierten Untereinheiten entfalten können und das Monomer-Dimer-Gleichgewicht bei mittleren Konzentrationen an Denaturierungsmittel auf der Seite der Dimere liegt. Durch die extrem langsame Entfaltung zeigen beide Proteine eine apparente Hysterese im Gleichgewichtsübergang, und es ist nicht möglich, die thermodynamische Stabilität zu bestimmen. Die Stabilität und die Geschwindigkeit der Assoziation und Dissoziation in die prozessierten bzw. nichtprozessierten Untereinheiten sind für beide Proteine gleich. Darüber hinaus konnte gezeigt werden, dass auch unter

  5. Meteorite. Urmaterie aus dem interplanetaren Raum.

    NASA Astrophysics Data System (ADS)

    Bühler, R. W.

    Contents: 1. Wie Irrlichter aus irdischen Dünsten. 2. Steine und Eisen aus dem Weltraum. 3. Die Meteoritenfunde in der Antarktis. 4. Einschläge auf die Erde. 5. Staubkörner und Riesenbrocken. 6. Systematik, Mineralogie, Petrologie, Zusammensetzung. 7. Ursprungsorte und wissenschaftliche Bedeutung der Meteorite. 8. Meteorite erkennen und konservieren.9. Meteoriten-Sammlungen in Europa.

  6. Werk und Leben Walter Christallers . Auszüge aus der Festrede anläßlich der Verleihung des Walter-Christaller-Preises 1996

    NASA Astrophysics Data System (ADS)

    Hottes, Ruth

    1997-03-01

    Unter der Betreuung und Federführung von Robert Gradmann promovierte am Erlanger Geographischen Institut 1932 Walter Christaller mit seiner Dissertation `Die Zentralen Orte in Süddeutschland'. Diese mit summa cum laude bewertete Monographie sollte die vielleicht berühmteste geographische Doktorarbeit unseres Jahrhunderts werden. Sie hat in den vergangenen Jahrzehnten einen beispiellosen Siegeszug angetreten. Heute gilt sie für Geographie, Raumwirtschaftslehre, Stadtforschung und Standorttheorie als eine bahnbrechende Grundkonzeption, und sie ist von größter Bedeutung für Raumordnungspolitik und Planungspraxis."

  7. Advanced Communication and Control Solutions of Distributed Energy Resources (DER)

    SciTech Connect

    Asgeirsson, Haukur; Seguin, Richard; Sherding, Cameron; de Bruet, Andre, G.; Broadwater, Robert; Dilek, Murat

    2007-01-10

    This report covers work performed in Phase II of a two phase project whose objective was to demonstrate the aggregation of multiple Distributed Energy Resources (DERs) and to offer them into the energy market. The Phase I work (DE-FC36-03CH11161) created an integrated, but distributed, system and procedures to monitor and control multiple DERs from numerous manufacturers connected to the electric distribution system. Procedures were created which protect the distribution network and personnel that may be working on the network. Using the web as the communication medium for control and monitoring of the DERs, the integration of information and security was accomplished through the use of industry standard protocols such as secure SSL,VPN and ICCP. The primary objective of Phase II was to develop the procedures for marketing the power of the Phase I aggregated DERs in the energy market, increase the number of DER units, and implement the marketing procedures (interface with ISOs) for the DER generated power. The team partnered with the Midwest Independent System Operator (MISO), the local ISO, to address the energy market and demonstrate the economic dispatch of DERs in response to market signals. The selection of standards-based communication technologies offers the ability of the system to be deployed and integrated with other utilities’ resources. With the use of a data historian technology to facilitate the aggregation, the developed algorithms and procedures can be verified, audited, and modified. The team has demonstrated monitoring and control of multiple DERs as outlined in phase I report including procedures to perform these operations in a secure and safe manner. In Phase II, additional DER units were added. We also expanded on our phase I work to enhance communication security and to develop the market model of having DERs, both customer and utility owned, participate in the energy market. We are proposing a two-part DER energy market model--a utility

  8. 3D-Meshes aus medizinischen Volumendaten

    NASA Astrophysics Data System (ADS)

    Zelzer, Sascha; Meinzer, Hans-Peter

    Diese Arbeit beschreibt eine template-basierte Methode zur Erzeugung von adaptiven Hexaeder-Meshes aus Volumendaten, welche komplizierte konkave Strukturen aufweisen können. Es wird ein vollständiger Satz von Templates generiert der es erlaubt, die Ränder konkaver Regionen feiner zu zerlegen als angrenzende Bereiche und somit die Gesamtzahl an Hexaeder verringert. Der Algorithmus arbeitet mit beliebigen gelabelten Volumendaten und erzeugt ein adaptives, konformes, reines Hexaeder-Mesh.

  9. Distributed Energy Resources Customer Adoption Model Plus (DER-CAM+), Version 1.0.0

    SciTech Connect

    Stadler, Michael; Cardorso, Goncalo; Mashayekh, Salman; DeForest, Nicholas

    2016-03-24

    DER-CAM+ v1.0.0 is internally referred to as DER-CAM v5.0.0. Due to fundamental changes from previous versions, a new name (DER-CAM+) will be used for DER-CAM version 5.0.0 and above. DER-CAM+ is a Decision Support Tool for Decentralized Energy Systems that has been tailored for microgrid applications, and now explicitly considers electrical and thermal networks within a microgrid, ancillary services, and operating reserve. DER-CAM was initially created as an exclusively economic energy model, able to find the cost minimizing combination and operation profile of a set of DER technologies that meet energy loads of a building or microgrid for a typical test year. The previous versions of DER-CAM were formulated without modeling the electrical/thermal networks within the microgrid, and hence, used aggregate single-node approaches. Furthermore, they were not able to consider operating reserve constraints, and microgrid revenue streams from participating in ancillary services markets. This new version DER-CAM+ considers these issues by including electrical power flow and thermal flow equations and constraints in the microgrid, revenues from various ancillary services markets, and operating reserve constraints.

  10. Thermionic Energy Conversion Based on Graphene van der Waals Heterostructures

    PubMed Central

    Liang, Shi-Jun; Liu, Bo; Hu, Wei; Zhou, Kun; Ang, L. K.

    2017-01-01

    Seeking for thermoelectric (TE) materials with high figure of merit (or ZT), which can directly converts low-grade wasted heat (400 to 500 K) into electricity, has been a big challenge. Inspired by the concept of multilayer thermionic devices, we propose and design a solid-state thermionic devices (as a power generator or a refrigerator) in using van der Waals (vdW) heterostructure sandwiched between two graphene electrodes, to achieve high energy conversion efficiency in the temperature range of 400 to 500 K. The vdW heterostructure is composed of suitable multiple layers of transition metal dichalcogenides (TMDs), such as MoS2, MoSe2, WS2 and WSe2. From our calculations, WSe2 and MoSe2 are identified as two ideal TMDs (using the reported experimental material’s properties), which can harvest waste heat at 400 K with efficiencies about 7% to 8%. To our best knowledge, this design is the first in combining the advantages of graphene electrodes and TMDs to function as a thermionic-based device. PMID:28387363

  11. Thermionic Energy Conversion Based on Graphene van der Waals Heterostructures

    NASA Astrophysics Data System (ADS)

    Liang, Shi-Jun; Liu, Bo; Hu, Wei; Zhou, Kun; Ang, L. K.

    2017-04-01

    Seeking for thermoelectric (TE) materials with high figure of merit (or ZT), which can directly converts low-grade wasted heat (400 to 500 K) into electricity, has been a big challenge. Inspired by the concept of multilayer thermionic devices, we propose and design a solid-state thermionic devices (as a power generator or a refrigerator) in using van der Waals (vdW) heterostructure sandwiched between two graphene electrodes, to achieve high energy conversion efficiency in the temperature range of 400 to 500 K. The vdW heterostructure is composed of suitable multiple layers of transition metal dichalcogenides (TMDs), such as MoS2, MoSe2, WS2 and WSe2. From our calculations, WSe2 and MoSe2 are identified as two ideal TMDs (using the reported experimental material’s properties), which can harvest waste heat at 400 K with efficiencies about 7% to 8%. To our best knowledge, this design is the first in combining the advantages of graphene electrodes and TMDs to function as a thermionic-based device.

  12. Optimizing Distributed Energy Resources and building retrofits with the strategic DER-CAModel

    SciTech Connect

    Stadler, M.; Groissböck, M.; Cardoso, G.; Marnay, C.

    2014-08-05

    The pressuring need to reduce the import of fossil fuels as well as the need to dramatically reduce CO2 emissions in Europe motivated the European Commission (EC) to implement several regulations directed to building owners. Most of these regulations focus on increasing the number of energy efficient buildings, both new and retrofitted, since retrofits play an important role in energy efficiency. Overall, this initiative results from the realization that buildings will have a significant impact in fulfilling the 20/20/20-goals of reducing the greenhouse gas emissions by 20%, increasing energy efficiency by 20%, and increasing the share of renewables to 20%, all by 2020. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an optimization tool used to support DER investment decisions, typically by minimizing total annual costs or CO2 emissions while providing energy services to a given building or microgrid site. This document shows enhancements made to DER-CAM to consider building retrofit measures along with DER investment options. Specifically, building shell improvement options have been added to DER-CAM as alternative or complementary options to investments in other DER such as PV, solar thermal, combined heat and power, or energy storage. The extension of the mathematical formulation required by the new features introduced in DER-CAM is presented and the resulting model is demonstrated at an Austrian Campus building by comparing DER-CAM results with and without building shell improvement options. Strategic investment results are presented and compared to the observed investment decision at the test site. Results obtained considering building shell improvement options suggest an optimal weighted average U value of about 0.53 W/(m2K) for the test site. This result is approximately 25% higher than what is currently observed in the building, suggesting that the retrofits made in 2002 were not optimal. Furthermore

  13. Optimizing Distributed Energy Resources and building retrofits with the strategic DER-CAModel

    DOE PAGES

    Stadler, M.; Groissböck, M.; Cardoso, G.; ...

    2014-08-05

    The pressuring need to reduce the import of fossil fuels as well as the need to dramatically reduce CO2 emissions in Europe motivated the European Commission (EC) to implement several regulations directed to building owners. Most of these regulations focus on increasing the number of energy efficient buildings, both new and retrofitted, since retrofits play an important role in energy efficiency. Overall, this initiative results from the realization that buildings will have a significant impact in fulfilling the 20/20/20-goals of reducing the greenhouse gas emissions by 20%, increasing energy efficiency by 20%, and increasing the share of renewables to 20%,more » all by 2020. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an optimization tool used to support DER investment decisions, typically by minimizing total annual costs or CO2 emissions while providing energy services to a given building or microgrid site. This document shows enhancements made to DER-CAM to consider building retrofit measures along with DER investment options. Specifically, building shell improvement options have been added to DER-CAM as alternative or complementary options to investments in other DER such as PV, solar thermal, combined heat and power, or energy storage. The extension of the mathematical formulation required by the new features introduced in DER-CAM is presented and the resulting model is demonstrated at an Austrian Campus building by comparing DER-CAM results with and without building shell improvement options. Strategic investment results are presented and compared to the observed investment decision at the test site. Results obtained considering building shell improvement options suggest an optimal weighted average U value of about 0.53 W/(m2K) for the test site. This result is approximately 25% higher than what is currently observed in the building, suggesting that the retrofits made in 2002 were not optimal. Furthermore, the results obtained with

  14. TÜV - Zertifizierungen in der Life Science Branche

    NASA Astrophysics Data System (ADS)

    Schaff, Peter; Gerbl-Rieger, Susanne; Kloth, Sabine; Schübel, Christian; Daxenberger, Andreas; Engler, Claus

    Life Sciences [1] (Lebenswissenschaften) sind ein globales Innovationsfeld mit Anwendungen der Bio- und Medizinwissenschaften, der Pharma-, Chemie-, Kosmetik- und Lebensmittelindustrie. Diese Branche zeichnet sich durch eine stark interdisziplinäre Ausrichtung aus, mit Anwendung wissenschaftlicher Erkenntnisse und Einsatz von Ausgangsstoffen aus der modernen Biologie, Chemie und Humanmedizin sowie gezielter marktwirtschaftlich orientierter Arbeit.

  15. Wasserundurchlässige Bauten aus Beton

    NASA Astrophysics Data System (ADS)

    Lohmeyer, Gottfried C. O.

    Für die Dichtigkeit von Bauwerken oder Bauteilen ist außer der Verwendung geeigneter Abdichtungsstoffe auch eine günstige Konstruktion von Bedeutung. Sofern die Abdichtung nicht nach DIN 18195 "Bauwerksabdichtungen“ mit den dort genannten Stoffen erfolgt (z.B. Bitumen- oder Kunststoffdichtungsbahnen) oder Sonderabdichtungen zum Einsatz kommen, ist die Abdichtung mit Beton auszuführen, der einen hohen Wassereindringwiderstand aufweist. Dieser Beton wird auch als wasserundurchlässiger Beton (WU-Beton) bezeichnet. Maßgebend für das Bauen mit wasserundurchlässigem Beton sind die Normen DIN 1045-1 bis 1045-4 "Tragwerke aus Beton, Stahlbeton und Spannbeton“ [10.1, 10.2] und die Richtlinie "Wasserundurchlässige Bauwerke aus Beton (WU-Richtlinie)“ vom Deutschen Ausschuss für Stahlbeton DAfStb [10.19].

  16. Graphene on boron-nitride: Moiré pattern in the van der Waals energy

    SciTech Connect

    Neek-Amal, M.; Peeters, F. M.

    2014-01-27

    The spatial dependence of the van der Waals (vdW) energy between graphene and hexagonal boron-nitride (h-BN) is investigated using atomistic simulations. The van der Waals energy between graphene and h-BN shows a hexagonal superlattice structure identical to the observed Moiré pattern in the local density of states, which depends on the lattice mismatch and misorientation angle between graphene and h-BN. Our results provide atomistic features of the weak van der Waals interaction between graphene and BN which are in agreement with experiment and provide an analytical expression for the size of the spatial variation of the weak van der Waals interaction. We also found that the A-B-lattice symmetry of graphene is broken along the armchair direction.

  17. AusEinetter, 1997.

    ERIC Educational Resources Information Center

    AusEinetter, 1997

    1997-01-01

    This document comprises the two AusEinetter newsletters published in 1997. The first newletter describes the background and structure of Australia's Early Intervention Network for Mental Health in Young People (AusEinet) and discusses the necessity of early intervention for mental health issues in young people 5-25 years of age. The following…

  18. Segmentierung des Femurs aus MRT-Daten mit Shape-Based Level-Sets

    NASA Astrophysics Data System (ADS)

    Dekomien, Claudia; Busch, Martin; Teske, Wolfram; Winter, Susanne

    Inhalt dieser Arbeit ist die Segmentierung des Femurs aus MRT-Datensätzen mit einem Shape-based Level-Set-Ansatz. Der Algorithmus besteht aus zwei Phasen, der Modellerstellung und der Segmentierungsphase. In der Segmentierungsphase wurde ein kantenbasiertes und ein auf Intensitäten basierendes Optimierungskriterium mit einander kombiniert. Für eine lokale Verbesserung des Ergebnisses wurde zusätzlich ein Laplacian Level-Set-Verfahren angewendet. Der Femur konnte mit diesem Ansatz in drei verschiedenen MRT-Sequenzen und einem Fusionsdatensatz gut segmentiert werden.

  19. Probing low-energy hyperbolic polaritons in van der Waals crystals with an electron microscope.

    PubMed

    Govyadinov, Alexander A; Konečná, Andrea; Chuvilin, Andrey; Vélez, Saül; Dolado, Irene; Nikitin, Alexey Y; Lopatin, Sergei; Casanova, Fèlix; Hueso, Luis E; Aizpurua, Javier; Hillenbrand, Rainer

    2017-07-21

    Van der Waals materials exhibit intriguing structural, electronic, and photonic properties. Electron energy loss spectroscopy within scanning transmission electron microscopy allows for nanoscale mapping of such properties. However, its detection is typically limited to energy losses in the eV range-too large for probing low-energy excitations such as phonons or mid-infrared plasmons. Here, we adapt a conventional instrument to probe energy loss down to 100 meV, and map phononic states in hexagonal boron nitride, a representative van der Waals material. The boron nitride spectra depend on the flake thickness and on the distance of the electron beam to the flake edges. To explain these observations, we developed a classical response theory that describes the interaction of fast electrons with (anisotropic) van der Waals slabs, revealing that the electron energy loss is dominated by excitation of hyperbolic phonon polaritons, and not of bulk phonons as often reported. Thus, our work is of fundamental importance for interpreting future low-energy loss spectra of van der Waals materials.Here the authors adapt a STEM-EELS system to probe energy loss down to 100 meV, and apply it to map phononic states in hexagonal boron nitride, revealing that the electron loss is dominated by hyperbolic phonon polaritons.

  20. Assessment of (mu)grid distributed energy resource potential using DER-CAM and GIS

    SciTech Connect

    Edwards, Jennifer L.; Marnay, Chris; Bartholomew, Emily; Ouaglal, Boubekeur; Siddiqui, Afzal S.; LaCommare, Kristina S.H.

    2002-01-01

    This report outlines an approach to assess the local potential for deployment of distributed energy resources (DER), small power-generation installations located close to the point where the energy they produce will be consumed. Although local restraints, such as zoning, building codes, and on-site physical barriers are well-known frustrations to DER deployment, no analysis method has been developed to address them within a broad economic analysis framework. The approach developed here combines established economic optimization techniques embedded in the Distributed Energy Resource Customer Adoption Model (DER-CAM) with a geographic information system (GIS) analysis of local land-use constraint. An example case in the San Diego area is developed from a strictly customer perspective, based on the premise that future development of DER may take the form of microgrids ((mu)Grids) under the control of current utility customers. Beginning with assumptions about which customer combinations h ave complementary energy loads, a GIS was used to locate specific neighborhoods in the San Diego area with promising customer combinations. A detailed energy analysis was conducted for the commercial/residential area chosen covering both electrical and heat energy requirements. Under various scenarios, different combinations of natural gas reciprocating engines were chosen by DER-CAM, ranging in size from 25 kW to 500 kW, often with heat recovery or absorption cooling. These generators typically operate throughout the day and are supplemented by purchased electricity during late-night and early-morning hours, when utility time-of-use prices are lowest. Typical (mu)Grid scenarios displaced about 80 percent of their annual gas heat load through CHP. Self-generation together with absorption cooling dramatically reduce electricity purchases, which usually only occur during nighttime hours.

  1. Connecting Distributed Energy Resources to the Grid: Their Benefits to the DER Owner etc.

    SciTech Connect

    Poore, WP

    2003-07-09

    The vision of the Distributed Energy Research Program (DER) program of the U.S. Department of Energy (DOE) is that the United States will have the cleanest and most efficient and reliable energy system in the world by maximizing the use of affordable distributed energy resources. Electricity consumers will be able to choose from a diverse number of efficient, cost-effective, and environmentally friendly distributed energy options and easily connect them into the nation's energy infrastructure while providing benefits to their owners and other stakeholders. The long-term goal of this vision is that DER will achieve a 20% share of new electric capacity additions in the United States by 2010, thereby helping to make the nation's electric power generation and delivery system more efficient, reliable, secure, clean, economical, and diverse in terms of fuel use (oil, natural gas, solar, hydroelectric, etc.) and prime mover resource (solar, wind, gas turbines, etc.). Near- and mid-term goals are to develop new technologies for implementing and operating DER and address barriers associated with DER usage and then to reduce costs and emissions and improve the efficiency and reliability of DER. Numerous strategies for meeting these goals have been developed into a research, development, and demonstration (RD&D) program that supports generation and delivery systems architecture, including modeling and simulation tools. The benefits associated with DER installations are often significant and numerous. They almost always provide tangible economic benefits, such as energy savings or transmission and distribution upgrade deferrals, as well as intangible benefits, such as power quality improvements that lengthen maintenance or repair intervals for power equipment. Also, the benefits routinely are dispersed among end users, utilities, and the public. For instance, an end user may use the DER to reduce their peak demand and save money due to lower demand charges. Reduced end user

  2. Surface energy and wettability of van der Waals structures

    NASA Astrophysics Data System (ADS)

    Annamalai, Meenakshi; Gopinadhan, Kalon; Han, Sang A.; Saha, Surajit; Park, Hye Jeong; Cho, Eun Bi; Kumar, Brijesh; Patra, Abhijeet; Kim, Sang-Woo; Venkatesan, T.

    2016-03-01

    The wetting behaviour of surfaces is believed to be affected by van der Waals (vdW) forces; however, there is no clear demonstration of this. With the isolation of two-dimensional vdW layered materials it is possible to test this hypothesis. In this paper, we report the wetting behaviour of vdW heterostructures which include chemical vapor deposition (CVD) grown graphene, molybdenum disulfide (MoS2) and tungsten disulfide (WS2) on few layers of hexagon boron nitride (h-BN) and SiO2/Si. Our study clearly shows that while this class of two-dimensional materials are not completely wetting transparent, there seems to be a significant amount of influence on their wetting properties by the underlying substrate due to dominant vdW forces. Contact angle measurements indicate that graphene and graphene-like layered transitional metal dichalcogenides invariably have intrinsically dispersive surfaces with a dominating London-vdW force-mediated wettability.The wetting behaviour of surfaces is believed to be affected by van der Waals (vdW) forces; however, there is no clear demonstration of this. With the isolation of two-dimensional vdW layered materials it is possible to test this hypothesis. In this paper, we report the wetting behaviour of vdW heterostructures which include chemical vapor deposition (CVD) grown graphene, molybdenum disulfide (MoS2) and tungsten disulfide (WS2) on few layers of hexagon boron nitride (h-BN) and SiO2/Si. Our study clearly shows that while this class of two-dimensional materials are not completely wetting transparent, there seems to be a significant amount of influence on their wetting properties by the underlying substrate due to dominant vdW forces. Contact angle measurements indicate that graphene and graphene-like layered transitional metal dichalcogenides invariably have intrinsically dispersive surfaces with a dominating London-vdW force-mediated wettability. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06705

  3. Evaluation der zentralen TUM-Lernplattform

    NASA Astrophysics Data System (ADS)

    Schulze, Elvira; Baume, Matthias; Graf, Stephan; Gergintchev, Ivan

    Die Notwendigkeit der Qualitätssicherung und -kontrolle für innovative universitäre Lehr-/Lernszenarien ist in der Praxis unbestritten. Die Wirksamkeit der Einführung der zentralen Lernplattform CLIX Campus der imc AG an der TUM wurde mittels quantitativer und qualitativer Evaluation überprüft. Als statistische Bewertungsgrundlage wurde der Erreichungsgrad bestimmter Projektziele herangezogen. Aufbauend auf den theoretischen Grundlagen der Evaluation von Bildungsangeboten gibt diese Studie Aufschluss über die Ergebnisse der Datenerhebungen sowie die Einschätzung der Plattform aus Nutzersicht und belegt die wesentliche Bedeutung der durchgängigen IT-Infrastruktur und speziell der einheitlichen Verfügbarkeit der eLearning Angebote.

  4. Role for Distributed Energy Resources (DER) in the Digital Economy

    SciTech Connect

    Key, Thomas S

    2007-11-01

    A large, and growing, part of the Nation's economy either serves or depends upon the information technology industry. These high-tech or "digital" enterprises are characterized by a dependence on electronic devices, need for completely reliable power supply, and intolerance to any power quality problems. In some cases these enterprises are densely populated with electronic loads and have very high energy usage per square foot. Serving these enterprises presents both electric power and equipment cooling challenges. Traditional electric utilities are often hard-pressed to deliver power that meets the stringent requirements of digital customers, and the economic and social consequences of a service quality or reliability problem can be large. New energy delivery and control options must be developed to effectively serve a digital economy. This report explores how distributed energy resources, partnerships between utility and customer to share the responsibility for service quality, innovative facility designs, higher energy efficiencies and waste-heat utilization can be coupled to meet the needs of a growing digital economy.

  5. Vibrational energy transfer in molecular collisions andvan der Waals clusters: Experiments and trajectory calculations

    NASA Astrophysics Data System (ADS)

    Yoder, Laurie Miller

    2000-09-01

    Polyatomic molecules with significant amounts of vibrational energy have high state densities that preclude state-to-state energy transfer observations. Both experiments and calculations are used to quantify energy transfer within this energy continuum. The work focuses on vibrationally excited aromatic molecules containing 10 to 15 atoms (pyrazine, benzene, methylpyrazine, toluene, pyrimidine, and aniline). In collisional experiments, the average vibrational energy of hot molecules was monitored by infrared fluorescence as they were deactivated by collisions with the bath. The experimental data were modeled with master equation simulations. The results for pyrazine show that the temperature dependence of the energy transfer is weak, and the average energy transferred per collision is approximately linearly dependent on vibrational energy. The experimental data cannot be modeled without invoking a biexponential collision step-size distribution, which implies that ``supercollisions,'' or very strongly deactivating collisions, are important. Additional information on the dynamics of energy transfer can be obtained through the vibrational predissociation of van der Waals dimers, which is the half-collision analog of a full collision. The ion imaging technique and a velocity-resolved time-of-flight technique were used to quantify the recoil energy released in the vibrational predissociation of triplet state mixed van der Waals dimers which contain ~2000 to ~8000 cm-1 of vibrational energy. The resulting recoil energy distributions peak near zero energy and are monotonically decreasing functions of energy. The fraction of initially available vibrational energy that appears as recoil energy is small. The average recoil energy is not strongly dependent on the initial vibrational energy or the density of states of the aromatic donor. Completely statistical models are unable to describe the results. Vibrational energy transfer both in van der Waals cluster predissociation

  6. Statik starrer Körper in der Ebene

    NASA Astrophysics Data System (ADS)

    Böge, Gert; Böge, Wolfgang

    Die Kraft ist die Ursache einer Bewegungs- oder (und) Formänderung. Man arbeitet in der Statik mit dem Gedankenbild des "starren" Körpers, schließt also die bei jedem realen Körper auftretende Formänderung aus der Betrachtung aus. Jede Kraft lässt sich durch den Vergleich mit der Gewichtskraft eines Wägestücks messen. Eindeutige Kennzeichnung einer Kraft F erfordert drei Bestimmungsstücke (Abb. 9.1):

  7. van der Waals interaction energy and disjoining pressure at small separation.

    PubMed

    White, Lee R

    2010-03-01

    The divergence of the van der Waals interaction energy E(132)(L) between plane half-spaces 1 and 2 separated by medium 3 as the separation distance L tends to zero is naively thought of as due to the overlap of the atomic polarization centers. It follows that it may therefore be prevented by properly allowing for the finite size of the atomic species which would prevent the overlap. The distance cutoff model is a simple example of such a modification. The present paper demonstrates that this is not ultimately the origin of the divergence and, that although finite atomic dimensions would alleviate the embarrassment, non-overlap does not properly address the thermodynamic restriction that pertains to the interaction energy. By allowing in an albeit approximate way for the wavelength dependence of the material dielectric response functions epsilon(i xi, k) which arise naturally in the modern Lifshitz theory for this interaction, a form for the van der Waals energy and the corresponding disjoining pressure may be derived which obey the thermodynamic constraint and remove the divergence as L-->0. The energy and disjoining pressure in this new model are compared with the classic non-retarded results and the length cutoff model.

  8. Keplers Weg der Erforschung der wahren Planetenbahn. Ergebnisse aus der Durchsicht der handschriftlichen Manuskripte.

    NASA Astrophysics Data System (ADS)

    Bialas, V.

    The handwriting manuscripts with Kepler's preliminary studies for his Astronomia Nova (some 700 pages) represent the most important source material. By reconstructing his mathematical-geometrical considerations of planetary astronomy, especially his hypothesis vicaria and the introduction of an oval orbit, here modern mathematical formulas are used. A smaller part of the manuscripts deals with Kepler's - so to speak - "speculative" physics as actual cause of the planetary motion. The whole handwriting material together with a detailed commentary will be published in the next volume of the Munich Kepler Edition in 1998.

  9. Der II. Hauptsatz der Wärmelehre

    NASA Astrophysics Data System (ADS)

    Heintze, Joachim

    Wir haben in (4.44) den II. Hauptsatz als empirische Tatsache folgendermaßen formuliert: (i) Wärmeenergie geht von selbst nur von einem wärmeren Körper auf einen kälteren über, niemals in der umgekehrten Richtung. Nun werden wir beweisen, dass sich aus diesem Prinzip folgende äquivalente Formulierungen für den II. Hauptsatz ableiten lassen: (ii) Es ist unmöglich, ein Perpetuum mobile zweiter Art zu bauen, d. h. eine Maschine, die fortlaufend Wärmeenergie vollständig in mechanische Arbeit umsetzen kann. Eine Wärmekraftmaschine, die einen Kreisprozess mit der höchsten Temperatur Tw und der niedrigsten Temperatur Tk durchläuft, hat höchstens den Carnotschen Wirkungsgrad c = (Tw - Tk)/Tw. Wenn in der Maschine nur reversible Prozesse ablaufen, die gesamte Wärmezufuhr bei der Temperatur Tw erfolgt und ausschließlich bei der Temperatur Tw gekühlt wird, ist ihr Wirkungsgrad = C. Es gibt keine Wärmekraftmaschine, die eine bessere Ausnutzung der Wärmeenergie ermöglicht. (iv) In jedem thermodynamischen System existiert die Zustandsgröße Entropie, definiert durch ihr Differential dS = (dQrev)/T . Entropie kann erzeugt, aber nicht vernichtet werden. Bei Zustandsänderungen, die in einem abgeschlossenen System ablaufen, nimmt die Entropie entweder zu (irreversible Prozesse), oder sie bleibt konstant (reversible Prozesse). Im Anschluss an (iii) werden wir zur Definition der thermodynamischen Temperatur und bei der Diskussion von (iv) zu einem tieferen Verständnis der Entropie gelangen. Es zeigt sich, dass die Entropie das eigentliche Bindeglied zwischen Mechanik und Wärmelehre darstellt. Am Ende des Kapitels werden wir einige Anwendungen des II. Hauptsatzes betrachten.

  10. Van der Waals potential and vibrational energy levels of the ground state radon dimer

    NASA Astrophysics Data System (ADS)

    Sheng, Xiaowei; Qian, Shifeng; Hu, Fengfei

    2017-08-01

    In the present paper, the ground state van der Waals potential of the Radon dimer is described by the Tang-Toennies potential model, which requires five essential parameters. Among them, the two dispersion coefficients C6 and C8 are estimated from the well determined dispersion coefficients C6 and C8 of Xe2. C10 is estimated by using the approximation equation that C6C10/C82 has an average value of 1.221 for all the rare gas dimers. With these estimated dispersion coefficients and the well determined well depth De and Re the Born-Mayer parameters A and b are derived. Then the vibrational energy levels of the ground state radon dimer are calculated. 40 vibrational energy levels are observed in the ground state of Rn2 dimer. The last vibrational energy level is bound by only 0.0012 cm-1.

  11. 1-D Van der Waals Foams Heated by Ion Beam Energy Deposition

    SciTech Connect

    Zylstra, A; Barnard, J J; More, R M

    2010-03-19

    One dimensional simulations of various initial average density aluminum foams (modeled as slabs of solid metal separated by low density regions) heated by volumetric energy deposition are conducted with a Lagrangian hydrodynamics code using a van der Waals equation of state (EOS). The resulting behavior is studied to facilitate the design of future warm dense matter (WDM) experiments at LBNL. In the simulations the energy deposition ranges from 10 to 30 kJ/g and from 0.075 to 4.0 ns total pulse length, resulting in temperatures from approximately 1 to 4 eV. We study peak pressures and temperatures in the foams, expansion velocity, and the phase evolution. Five relevant time scales in the problem are identified. Additionally, we present a method for characterizing the level of inhomogeneity in a foam target as it is heated and the time it takes for a foam to homogenize.

  12. 1-D Van der Waals Foams Heated by Ion Beam Energy Deposition

    SciTech Connect

    Zylstra, A. B.; Barnard, J. J.; More, R. M.

    2009-12-23

    One dimensional simulations of various initial average density aluminum foams (modeled as slabs of solid metal separated by low density regions) heated by volumetric energy deposition are conducted with a Lagrangian hydrodynamics code using a van der Waals equation of tate (EOS). The resulting behavior is studied to facilitate the design of future warm dense matter (WDM) experiments at LBNL. In the simulations the energy deposition ranges from 10 to 30 kJ/g and from 0.075 to 4.0 ns total pulse length, resulting in temperatures from approximately 1 o 4 eV. We study peak pressures and temperatures in the foams, expansion velocity, and the phase evolution. Five relevant time scales in the problem are identified. Additionally, we present a method for characterizing the level of inhomogeneity in a foam target as it is heated and the time it takes for a foam to homogenize.

  13. Defining the role of histone deacetylases in the inhibition of mammary carcinogenesis by dietary energy restriction (DER): effects of suberoylanilide hydroxamic acid (SAHA) and DER in a rat model.

    PubMed

    Zhu, Zongjian; Jiang, Weiqin; McGinley, John N; Thompson, Henry J

    2013-04-01

    Dietary energy restriction (DER) inhibits experimentally induced mammary cancer, an effect accompanied by elevated levels of silent information regulator 2 (SIRT1), a class III histone deacetylase (HDAC). However, the effect of DER on targets of other classes of HDACs has not been reported, a highly relevant issue given evidence that HDAC induction favors the development of cancer and tumor growth. Experiments were carried out to determine whether suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor with broad activity, would affect the anti-cancer activity of DER. Female Sprague Dawley rats (n = 30/group) were injected with 1-methyl-1-nitrosourea (50 mg/kg) at 21 days of age and 7 days thereafter were randomized to groups fed: (i) control diet (AIN-93G), (ii) 0.1% SAHA (w/w), (iii) 40% DER, or (iv) 0.1% SAHA + 40% DER. An additional group was fed 0.1% SAHA + 40%DER for 5 weeks and released to control diet for 3 weeks. DER significantly reduced mammary cancer incidence, multiplicity, and cancer burden and prolonged cancer latency (P < 0.01). Cancer inhibition was maintained in SAHA + DER, despite evidence that histone (H2A(Lys9), H2B(Lys5), and H4(Lys5/8/12/16), but not H3(Lys9); P < 0.001) and non-histone protein deacetylation (p53(Lys373) and p53(Lys382); P < 0.001) induced by DER was reversed by SAHA. This indicates that the inhibition of DER of cancer is not dependent on HDAC induction. After releasing rats from DER + SAHA, cancer multiplicity remained lower than control (P < 0.05), consistent with apoptosis-mediated cell deletion. These findings support further investigation of the hypothesis that HDAC induction by DER blunts its anti-carcinogenic impact.

  14. Theoretische Konzepte der Physik

    NASA Astrophysics Data System (ADS)

    Longair, Malcolm S.; Simon, B.; Simon, H.

    "Dies ist kein Lehrbuch der theoretischen Physik, auch kein Kompendium der Physikgeschichte ... , vielmehr eine recht anspruchsvolle Sammlung historischer Miniaturen zur Vergangenheit der theoretischen Physik - ihrer "Sternstunden", wenn man so will. Frei vom Zwang, etwas Erschöpfendes vorlegen zu müssen, gelingt dem Autor etwas Seltenes: einen "lebendigen" Zugang zum Ideengebäude der modernen Physik freizulegen, ... zu zeigen, wie Physik in praxi entsteht... Als Vehikel seiner Absichten dienen dem Autor geschichtliche Fallstudien, insgesamt sieben an der Zahl. Aus ihnen extrahiert er das seiner Meinung nach Lehrhafte, dabei bestrebt, mathematische Anachronismen womöglich zu vermeiden... Als Student hätte ich mir diese gescheiten Essays zum Werden unserer heutigen physikalischen Weltsicht gewünscht. Sie sind originell, didaktisch klug und genieren sich auch nicht, von der Faszination zu sprechen, die ... von der Physik ausgeht. Unnötig darauf hinzuweisen, das sie ein gründliches "konventionelles" Studium weder ersetzen wollen noch können, sie vermögen aber, dazu zu ermuntern." #Astronomische Nachrichten (zur englischen Ausgabe)#1

  15. Explaining the Microtubule Energy Balance: Contributions Due to Dipole Moments, Charges, van der Waals and Solvation Energy.

    PubMed

    Ayoub, Ahmed Taha; Staelens, Michael; Prunotto, Alessio; Deriu, Marco A; Danani, Andrea; Klobukowski, Mariusz; Tuszynski, Jack Adam

    2017-09-22

    Microtubules are the main components of mitotic spindles, and are the pillars of the cellular cytoskeleton. They perform most of their cellular functions by virtue of their unique dynamic instability processes which alternate between polymerization and depolymerization phases. This in turn is driven by a precise balance between attraction and repulsion forces between the constituents of microtubules (MTs)-tubulin dimers. Therefore, it is critically important to know what contributions result in a balance of the interaction energy among tubulin dimers that make up microtubules and what interactions may tip this balance toward or away from a stable polymerized state of tubulin. In this paper, we calculate the dipole-dipole interaction energy between tubulin dimers in a microtubule as part of the various contributions to the energy balance. We also compare the remaining contributions to the interaction energies between tubulin dimers and establish a balance between stabilizing and destabilizing components, including the van der Waals, electrostatic, and solvent-accessible surface area energies. The energy balance shows that the GTP-capped tip of the seam at the plus end of microtubules is stabilized only by - 9 kcal/mol, which can be completely reversed by the hydrolysis of a single GTP molecule, which releases + 14 kcal/mol and destabilizes the seam by an excess of + 5 kcal/mol. This triggers the breakdown of microtubules and initiates a disassembly phase which is aptly called a catastrophe.

  16. Die Zeitung der Zukunft

    NASA Astrophysics Data System (ADS)

    Wieser, Christoph; Schaffert, Sebastian

    Schon lange wird spekuliert, wie wir in Zukunft Zeitung lesen werden. Werden wir am Frühstückstisch wie gewohnt in einer Zeitung aus Papier schmökern oder werden wir die Zeitung als biegsame Folie beschrieben mit elektronischer Tinte in Händen halten? Wird die Zeitung mit anderen Medien wie Radio und Fernsehen verschmelzen? Viele Varianten sind denkbar. Heute lässt sich schon ein Trend ablesen: Immer mehr Leser entdecken die Online-Zeitung als Informationsmedium, eine Voraussetzung für die Nutzung neuer Technologien in der Zeitung der Zukunft. In diesem Kapitel stellen wir Entwicklungsmöglichkeiten der Online-Zeitung dar, wie sie im Social Semantic Web möglich werden.

  17. Coronellis Cosmos in der Melker Stiftsbibliothek.

    NASA Astrophysics Data System (ADS)

    Glaßner, Gottfried; Pärr, Nora

    2009-06-01

    Die Melker Stiftsbibliothek besitzt ein Globenpaar des berühmten venezianischen Globenbauers Vincenzo Coronelli (1650-1718), einen Erdglobus von 1688 und einen Himmelsglobus von 1693. Wie und wann die beiden Globen nach Melk gekommen sind, ist nicht bekannt. Dass sie zur ursprünglichen Ausstattung der 1735 fertig gestellten Barockbibliothek gehörten, wird aber aus der zentralen Stellung deutlich, die dem Globus (Erdglobus und Armillarphäre) in dem von Paul Troger 1732 gemalten Deckenfresko zukommt. Mehrfach begegnet das Motiv des Globus als Attribut der Weisheit bzw. Philosophie, der Geographie bzw. Geometrie und der Astronomie in den beiden Hauptsälen wie auch in der Deckenmalerei von Johann Bergl in der Oberen Bibliothek (1768) und in der Kuppel des Gartenpavillons (1764).

  18. Die Wirkung als Naturkraft und die Herkunft von Zeit, Raum, Dimensionen, Naturkräften, und Gesetzen von Logik, Geometrie und Physik bei der Entstehung der Welt

    NASA Astrophysics Data System (ADS)

    Landgraf, Werner

    2011-02-01

    Das Wirkungs-Welt-Modell enthält eine einfache Beschreibung des Anfanges der Welt, wonach, ausgehend vom einfachsten Zustand der logisch notwendigen Bejahung ihrer Existenz innerhalb ihr selbst, alles sukzessiv bewirkt wird, und ihre logischen, geometrischen und physikalischen Eigenschaften Aspekte der Verkörperung und Fortwirkung primordialer Fakten darstellen, ohne externe Schöpfung auszuschließen. Die ersten Dimensionen und sie formal und subjektiv charakterisierenden Größen sind: Informationsmenge und Wirkung, mit abzählbarem Ereignis und Wirkungsquantum; Zeit und Energie, mit deren Planck-Einheiten; Geschwindigkeit oder Strecke und Impuls, mit Lichtgeschwindigkeit oder Planck-Länge; Krümmung oder zwei räumliche Richtungen, mit Gravitationskonstanten, und aus den ihnen entsprechenden primären Naturkräften setzen sich die uns geläufigen zusammen.

  19. Entwicklung und Formulierung der Unternehmensstrategie

    NASA Astrophysics Data System (ADS)

    Crespo, Isabel; Bergmann, Lars; Lacker, Thomas

    Ursprünglich stammt der Begriff "Strategie“ aus dem Altgriechischen: "strategos“ bedeutete "Heer“, "Heeresmacht“ und damit auch "konzentrierte Kraft“; das Wort "agein“ bedeutete "tun, machen, treiben“. Ein Stratege war also eine Person, die ein Heer führte und damit Kraft, Macht und Stärke konzentrierte und einsetzen konnte. Strategie bezeichnete dementsprechend die Maßnahmen, die in dieser Funktion entwickelt wurden. Daher ist es leicht verständlich, dass der Begriff Strategie bis in die Mitte des letzten Jahrhunderts in erster Linie militärisch verstanden wurde. Anschließend wurde der Begriff in weiteren Bereichen, wie beispielsweise der Unternehmensführung, verwendet. Im betriebswirtschaftlichen Sinne bedeutet der Begriff Strategie die langfristig geplante Verhaltensweise eines Unternehmens zur Erreichung seiner Ziele.

  20. Potential energy surface and rovibrational energy levels of the H2-CS van der Waals complex.

    PubMed

    Denis-Alpizar, Otoniel; Stoecklin, Thierry; Halvick, Philippe; Dubernet, Marie-Lise; Marinakis, Sarantos

    2012-12-21

    Owing to its large dipole, astrophysicists use carbon monosulfide (CS) as a tracer of molecular gas in the interstellar medium, often in regions where H(2) is the most abundant collider. Predictions of the rovibrational energy levels of the weakly bound complex CS-H(2) (not yet observed) and also of rate coefficients for rotational transitions of CS in collision with H(2) should help to interpret the observed spectra. This paper deals with the first goal, i.e., the calculation of the rovibrational energy levels. A new four-dimensional intermolecular potential energy surface for the H(2)-CS complex is presented. Ab initio potential energy calculations were carried out at the coupled-cluster level with single and double excitations and a perturbative treatment of triple excitations, using a quadruple-zeta basis set and midbond functions. The potential energy surface was obtained by an analytic fit of the ab initio data. The equilibrium structure of the H(2)-CS complex is found to be linear with the carbon pointing toward H(2) at the intermolecular separation of 8.6 a(o). The corresponding well depth is -173 cm(-1). The potential was used to calculate the rovibrational energy levels of the para-H(2)-CS and ortho-H(2)-CS complexes. The present work provides the first theoretical predictions of these levels. The calculated dissociation energies are found to be 35.9 cm(-1) and 49.9 cm(-1), respectively, for the para and ortho complexes. The second virial coefficient for the H(2)-CS pair has also been calculated for a large range of temperature. These results could be used to assign future experimental spectra and to check the accuracy of the potential energy surface.

  1. Assoziativspeicher und eine erste Skizze von Konrad Zuse aus dem Jahre 1943

    NASA Astrophysics Data System (ADS)

    Waldschmidt, Klaus

    In dem Beitrag wird eine Handskizze von Konrad Zuse aus dem Jahre 1943 eines assoziativen Speichers in Relaistechnik diskutiert. Die Diskussion ist eingebettet in die Grundlagen des assoziativen Speicherproblems. Zum Schluss des Beitrages werden einige Vorschläge zu MOSRealisierung der Zuse-Schaltung unterbreitet.

  2. The potential for distributed generation in Japanese prototype buildings: A DER-CAM analysis of policy, tariff design, building energy use, and technology development (Japanese translation)

    SciTech Connect

    Zhou, Nan; Marnay, Chris; Firestone, Ryan; Gao, Weijun; Nishida, Masaru

    2004-10-15

    The August 2003 blackout of the northeastern U.S. and CANADA caused great economic losses and inconvenience to New York City and other affected areas. The blackout was a warning to the rest of the world that the ability of conventional power systems to meet growing electricity demand is questionable. Failure of large power systems can lead to serious emergencies. Introduction of on-site generation, renewable energy such as solar and wind power and the effective utilization of exhaust heat is needed, to meet the growing energy demands of the residential and commercial sectors. Additional benefit can be achieved by integrating these distributed technologies into distributed energy resource (DER) systems. This work demonstrates a method for choosing and designing economically optimal DER systems. An additional purpose of this research is to establish a database of energy tariffs, DER technology cost and performance characteristics, and building energy consumption for Japan. This research builds on prior DER studies at the Ernest Orlando Lawrence Berkeley National Laboratory (LBNL) and with their associates in the Consortium for Electric Reliability Technology Solutions (CERTS) and operation, including the development of the microgrid concept, and the DER selection optimization program, the Distributed Energy Resources Customer Adoption Model (DER-CAM). DER-CAM is a tool designed to find the optimal combination of installed equipment and an idealized operating schedule to minimize a site's energy bills, given performance and cost data on available DER technologies, utility tariffs, and site electrical and thermal loads over a test period, usually an historic year. Since hourly electric and thermal energy data are rarely available, they are typically developed by building simulation for each of six end use loads used to model the building: electric-only loads, space heating, space cooling, refrigeration, water heating, and natural-gas-only loads. DER-CAM provides a

  3. Energy-based analysis of frequency entrainment described by van der Pol and phase-locked loop equations.

    PubMed

    Susuki, Yoshihiko; Yokoi, Yuuichi; Hikihara, Takashi

    2007-06-01

    This paper analyzes frequency entrainment described by van der Pol and phase-locked loop (PLL) equations. The PLL equation represents the dynamics of a PLL circuit that appear in typical phase-locking phenomena. These two equations describe frequency entrainment by a periodic force. The entrainment originates from two different types of limit cycles: libration for the van der Pol equation and rotation for the PLL one. To explore the relationship between the geometry of limit cycles and the mechanism of entrainment, we investigate the entrainment using an energy balance relation. This relation is equivalent to the energy conservation law of dynamical systems with dissipation and input terms. We show response curves for the dc component, harmonic amplitude, phase difference, and energy supplied by a periodic force. The obtained curves indicate that the entrainments for the two equations have different features of supplied energy, and that the entrainment for the PLL equation possibly has the same mechanism as does the regulation of the phase difference for the van der Pol equation.

  4. Energy-based analysis of frequency entrainment described by van der Pol and phase-locked loop equations

    NASA Astrophysics Data System (ADS)

    Susuki, Yoshihiko; Yokoi, Yuuichi; Hikihara, Takashi

    2007-06-01

    This paper analyzes frequency entrainment described by van der Pol and phase-locked loop (PLL) equations. The PLL equation represents the dynamics of a PLL circuit that appear in typical phase-locking phenomena. These two equations describe frequency entrainment by a periodic force. The entrainment originates from two different types of limit cycles: libration for the van der Pol equation and rotation for the PLL one. To explore the relationship between the geometry of limit cycles and the mechanism of entrainment, we investigate the entrainment using an energy balance relation. This relation is equivalent to the energy conservation law of dynamical systems with dissipation and input terms. We show response curves for the dc component, harmonic amplitude, phase difference, and energy supplied by a periodic force. The obtained curves indicate that the entrainments for the two equations have different features of supplied energy, and that the entrainment for the PLL equation possibly has the same mechanism as does the regulation of the phase difference for the van der Pol equation.

  5. Esaki Diodes in van der Waals Heterojunctions with Broken-Gap Energy Band Alignment.

    PubMed

    Yan, Rusen; Fathipour, Sara; Han, Yimo; Song, Bo; Xiao, Shudong; Li, Mingda; Ma, Nan; Protasenko, Vladimir; Muller, David A; Jena, Debdeep; Xing, Huili Grace

    2015-09-09

    van der Waals (vdW) heterojunctions composed of two-dimensional (2D) layered materials are emerging as a solid-state materials family that exhibits novel physics phenomena that can power a range of electronic and photonic applications. Here, we present the first demonstration of an important building block in vdW solids: room temperature Esaki tunnel diodes. The Esaki diodes were realized in vdW heterostructures made of black phosphorus (BP) and tin diselenide (SnSe2), two layered semiconductors that possess a broken-gap energy band offset. The presence of a thin insulating barrier between BP and SnSe2 enabled the observation of a prominent negative differential resistance (NDR) region in the forward-bias current-voltage characteristics, with a peak to valley ratio of 1.8 at 300 K and 2.8 at 80 K. A weak temperature dependence of the NDR indicates electron tunneling being the dominant transport mechanism, and a theoretical model shows excellent agreement with the experimental results. Furthermore, the broken-gap band alignment is confirmed by the junction photoresponse, and the phosphorus double planes in a single layer of BP are resolved in transmission electron microscopy (TEM) for the first time. Our results represent a significant advance in the fundamental understanding of vdW heterojunctions and broaden the potential applications of 2D layered materials.

  6. Effect of surface roughness on van der Waals and Casimir-Polder/Casimir attraction energies

    NASA Astrophysics Data System (ADS)

    Makeev, Maxim A.

    2017-09-01

    A theoretical model is devised to assess effects of surface roughness on dispersion interactions between macroscopic bodies, bounded by self-affine fractal surfaces and separated by a vacuum gap. The rough-surface profiles are described statistically by the saturation values of surface width and the correlation lengths; i.e., in terms of experimentally measurable quantities. The model devised takes into account the separation distance-dependent nature of dispersive interactions. The case of non-retarded van der Waals interactions, known to operate at smaller separation distances between the bodies, and that of retarded attractions, operative at larger separation length-scales, are treated separately in this work. Analytical formulae for the roughness corrections are deduced for the two aforementioned types of attractions. The model is employed to compute roughness corrections to interactions between an extended body, bounded by a self-affine surface, and: a) a point-like adherent; and b) a planar half-space. Furthermore, the roughness-induced corrections to dispersive interaction energies between half-spaces, both bounded by self-affine surfaces, are obtained under assumption that the corresponding surface profiles are not correlated. The predictions of the model are compared with some previously reported theoretical studies and available experimental data on the theme of dispersive adhesion between macroscopic bodies.

  7. Low-energy universality and scaling of van der Waals forces

    SciTech Connect

    Calle Cordon, A.; Ruiz Arriola, E.

    2010-04-15

    At long distances, interactions between neutral ground-state atoms can be described by the van der Waals potential. In the ultracold regime, atom-atom scattering is dominated by s-waves phase shifts given by an effective range expansion in terms of the scattering length {alpha}{sub 0} and the effective range r{sub 0}. We show that while the scattering length cannot be predicted for these potentials, the effective range is given by the universal low-energy theorem r{sub 0}=A+B/{alpha}{sub 0}+C/{alpha}{sub 0}{sup 2}, where A, B, and C depend on the dispersion coefficients C{sub n} and the reduced diatom mass. We confront this formula to about 100 determinations of r{sub 0} and {alpha}{sub 0} and show why the result is dominated by the leading dispersion coefficient C{sub 6}. Universality and scaling extend much beyond naive dimensional analysis estimates.

  8. Distributed Energy Resources Customer Adoption Model (DER-CAM), Investment & Planing Version 3.10.5.m

    SciTech Connect

    2014-04-01

    Version 3.10.5 is a multi-year Decision Support tool for Distributed Generation (DG). DER-CAM was initially created as an exclusively economic energy model, able to find the cost minimizing combination and operation profile of a set of DER technologies that meet heat and electric loads of a single building or microgrid for a typical test year. Now, version 3.10.5.m solves for a multiple-year horizon the technology choice question, the appropriate capacity for each selected technology as well as the operational and investment schedule. Optimized investment decisions are based on techno-economic criteria, along with site information such as energy loads, economic forecast, and technology characterization. Version 3.10.5 contains: 1. a PV and battery degradation model and 2. variable performance for technologies. Efficiency, investment costs, etc. can vary over time and model technology breakthroughs and advancements.

  9. Excitonic, vibrational, and van der Waals interactions in electron energy loss spectroscopy.

    PubMed

    Mizoguchi, T; Miyata, T; Olovsson, W

    2017-09-01

    The pioneer, Ondrej L. Krivanek, and his collaborators have opened up many frontiers for the electron energy loss spectroscopy (EELS), and they have demonstrated new potentials of the EELS method for investigating materials. Here, inspired by those achievements, we show further potentials of EELS based on the results of theoretical calculations, that is excitonic and van der Waals (vdW) interactions, as well as vibrational information of materials. Concerning the excitonic interactions, we highlight the importance of the two-particle calculation to reproduce the low energy-loss near-edge structure (ELNES), the Na-L2,3 edge of NaI and the Li-K edge of LiCl and LiFePO4. Furthermore, an unusually strong excitonic interaction at the O-K edge of perovskite oxides, SrTiO3 and LaAlO3, is shown. The effect of the vdW interaction in the ELNES is also investigated, and we observe that the magnitude of the vdW effect is approximately 0.1eV in the case of the ELNES from a solid and liquid, whereas its effect is almost negligible in the case of the ELNES from the gaseous phase owing to the long inter-molecular distance. In addition to the "static" information, the influence of the "dynamic" behavior of atoms in materials to EELS is also investigated. We show that measurements of the infrared spectrum are possible by using a modern monochromator system. Furthermore, an estimation of the atomic vibration in core-loss ELNES is also presented. We show the acquisition of vibrational information using the ELNES of liquid methanol and acetic acid, solid Al2O3, and oxygen gas. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Nomogramme der Sickerwasserprognose

    NASA Astrophysics Data System (ADS)

    Schneider, Wilfried; Stöfen, Heinke

    Kurzfassung Modelle zur Sickerwasserprognose stehen in unterschiedlicher Komplexität zur Verfügung. Komplexe Modelle werden aufgrund der schwierigen Handhabung und des enormen Eingabedatenumfangs in der Praxis kaum angewandt. Grobe Abschätzmethoden sind dagegen nicht ausreichend wissenschaftlich fundiert, um damit justiziable Ergebnisse erzielen zu können. Um die Kluft zwischen komplexer und einfacher, jedoch justiziabler sowie wissenschaftlich fundierter Methode zu schmälern, wurden Nomogramme für Sickerwasserprognosen zur Berücksichtigung der Endlichkeit der Quelle entwickelt. Mithilfe der Nomogramme können ohne Modellierungserfahrung schnell und einfach die zu erwartenden Schadstoffkonzentrationen am Ort der Beurteilung abgeschätzt werden, falls die Endlichkeit der Quelle der hauptsächlich zur Abminderung führende Prozess ist. Die Nomogramme basieren auf analytischen Lösungen der eindimensionalen Advektions-Dispersions-Gleichung. Sie berücksichtigen die Prozesse Advektion, Diffusion in Bodenwasser und -luft, Dispersion, lineare Sorption, Abbau 1. Ordnung innerhalb einer aus mehreren Bodenschichten bestehenden Sickerwasserzone, wobei die Endlichkeit der Schadstoffmasse in der Bodenkontamination einbezogen wird. Die Genauigkeit der Nomogramme wird dargestellt. Models of different complexity are available for groundwater risk assessment. In practice complex models are hardly used, due to their difficult handling and large data requirement. Rough estimation methods are not sufficiently scientifically founded to produce justiciable results. To reduce the gap between complex and easy to use but justiciable and scientifically founded methods we developed nomograms for groundwater risk assessment which take into account the finite mass of contaminant in the source. With the help of the nomograms the expected concentrations at the point of compliance (transition between the unsaturated and saturated zone) can be estimated easily, fast and without any

  11. Physik gestern und heute: Visualisierung mit der Schlierenmethode

    NASA Astrophysics Data System (ADS)

    Heering, Peter

    2006-07-01

    Der Name des österreichischen Forschers Ernst Mach ist heute noch mit der Schallgeschwindigkeit verbunden. Diese Auszeichnung resultiert aus Machs Untersuchungen, wie sich Projektile mit Überschallgeschwindigkeit durch die Luft bewegen. Gerade in jüngster Zeit hat die Anwendung derartiger Methoden durch technische Modifikationen wieder einen Aufschwung erfahren.

  12. Die Evolution der Religiosität

    NASA Astrophysics Data System (ADS)

    Voland, Eckart

    Ein konsequent darwinischer Blick auf den Menschen bedeutet, auch im Denken, Fühlen und Handeln biologische Anpassungsgeschichte zu suchen, denn auch die psychischen und mentalen Eigenheiten des Homo sapiens unterliegen der natürlichen Selektion. Lässt sich die religiöse Lebenspraxis von Menschen daher auch aus einer Fitnessperspektive betrachten?

  13. Amor und der Abstand zur Sonne. Geschichten aus meinem Kosmos

    NASA Astrophysics Data System (ADS)

    Kippenhahn, Rudolf

    2001-10-01

    R. Kippenhahn hat in vielen Büchern die Astronomie populär gemacht. Ihn interessieren dabei immer auch die kuriosen Aspekte seiner Wissenschaft. Von ihnen erzählt er in den kleinen Geschichten dieses Buches.

  14. Van der Waals Type Model for Neutron-Proton Elastic Scattering at High Energies

    NASA Astrophysics Data System (ADS)

    Aleem, F.

    1980-12-01

    The most recent measurements of the angular distribution and total cross-section for neutron-proton elastic scattering between 70< pL <400 GeV/c with squared four momentum transfer -t ≤ 3.6 (GeV/c)2 have been explained using Van der Waals type model.

  15. Van der Waals Type Model and Structure in π-p Elastic Scattering at High Energies

    NASA Astrophysics Data System (ADS)

    Aleem, F.

    1982-10-01

    The most recent measurement of the angular distribution for π-p elastic scattering at pL =50 and 200 GeV/c which show a structure near -t ≈ 4(GeV/c)2, with squared four momentum transfer -t extended to 10(GeV/c)2, and the total cross section data for 50 ≤ pL ≤ 370 GeV/c have been simultaneously explained by using Van der Waal's type model.

  16. Recoil energy distributions for dissociation of the van der Waals molecule p-difluorobenzene-Ar with 450-3000 cm(-1) excess energy.

    PubMed

    Bellm, Susan M; Lawrance, Warren D

    2005-03-08

    Velocity map imaging has been used to measure the distributions of translational energy released in the dissociation of p-difluorobenzene-Ar van der Waals complexes from the 5(1), 3(1), 5(2), 3(1)5(1), 5(3), 3(2), and 3(2)5(1) states. These states span 818-3317 cm(-1) of vibrational energy and correspond to a range of energies above dissociation of 451-2950 cm(-1). The translational energy release (recoil energy) distributions are remarkably similar, peaking at very low energy (10-20 cm(-1)) and decaying in an exponential fashion to approach zero near 300 cm(-1). The average translational energy released is small, shows no dependence on the initial vibrational energy, and spans the range 58-72 cm(-1) for the vibrational levels probed. The average value for the seven levels studied is 63 cm(-1). The low fraction of transfer to translation is qualitatively in accord with Ewing's momentum gap model [G. E. Ewing, Faraday Discuss. 73, 325 (1982)]. No evidence is found in the distributions for a high energy tail, although it is likely that the experiment is not sufficiently sensitive to detect a low fraction of transfer at high translational energies. The average translational energy released is lower than has been seen in comparable systems dissociating from triplet and cation states.

  17. Haftung in der Medizintechnik

    NASA Astrophysics Data System (ADS)

    Müller, Ute; Lücker, Volker

    Die Unversehrtheit von Leib und Leben ist das größte Rechtsgut unserer Gesellschaft. Dies macht schon das Grundgesetz in Art. 2 Abs. Satz 1 GG deutlich. Die Öffentlichkeit zeigt daher größtes Interesse an Produkten, welche der Gesundheit dienen und Leben retten oder erhalten. Dieses Interesse gilt einerseits der Entwicklung und Bereitstellung leistungsfähiger Medizinprodukte, andererseits zielt es auf deren Sicherheit. Um vor allem letztere zu gewährleisten, nimmt der Gesetzgeber alle Beteiligten in die Pflicht, die auftretenden Risiken auf das geringstmögliche Maß zu begrenzen. Dies spiegelt sich in den rechtlichen Vorgaben ebenso wie in den Haftungsfolgen, die bei Verletzung dieser Vorgaben greifen, wieder. Diese Folgen können dementsprechend gravierend ausfallen, von Geldstrafen bis zu Freiheitsstrafen, von Bußgeldzahlungen bis zum Schadenersatzansprüchen, die schnell ein wirtschaftliches Aus bedeuten können. Den Beteiligten, allen voran den Herstellern, muss deshalb daran gelegen sein, nicht nur die Produkte, sondern auch deren Sicherheit stetig weiter zu entwickeln.

  18. Effect of the van der Waals interaction on the electron energy-loss near edge structure theoretical calculation.

    PubMed

    Katsukura, Hirotaka; Miyata, Tomohiro; Tomita, Kota; Mizoguchi, Teruyasu

    2017-07-01

    The effect of the van der Waals (vdW) interaction on the simulation of the electron energy-loss near edge structure (ELNES) by a first-principles band-structure calculation is reported. The effect of the vdW interaction is considered by the Tkatchenko-Scheffler scheme, and the change of the spectrum profile and the energy shift are discussed. We perform calculations on systems in the solid, liquid and gaseous states. The transition energy shifts to lower energy by approximately 0.1eV in the condensed (solid and liquid) systems by introducing the vdW effect into the calculation, whereas the energy shift in the gaseous models is negligible owing to the long intermolecular distance. We reveal that the vdW interaction exhibits a larger effect on the excited state than the ground state owing to the presence of an excited electron in the unoccupied band. Moreover, the vdW effect is found to depend on the local electron density and the molecular coordination. In addition, this study suggests that the detection of the vdW interactions exhibited within materials is possible by a very stable and high resolution observation. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Energy of van der Waals and dipole-dipole interactions between atoms in Rydberg states

    NASA Astrophysics Data System (ADS)

    Kamenski, A. A.; Manakov, N. L.; Mokhnenko, S. N.; Ovsiannikov, V. D.

    2017-09-01

    The van der Waals coefficient C6(θ ;n l J M ) of two like Rydberg atoms in their identical Rydberg states |n l J M 〉 is resolved into four irreducible components called scalar Rs s, axial (vector) Ra a, scalar-tensor Rs T=RT s , and tensor-tensor RT T parts in analogy with the components of dipole polarizabilities. The irreducible components determine the dependence of C6(θ ;n l J M ) on the angle θ between the interatomic and the quantization axes of atoms. The spectral resolution for the biatomic Green's function with account of the most contributing terms is used for evaluating the components Rα β of atoms in their Rydberg series of doublet states of the low angular momenta (2S , 2P , 2D , 2F ). The polynomial presentations in powers of the Rydberg-state principal quantum number n taking into account the asymptotic dependence C6(θ ;n l J M ) ∝n11 are derived for simplified evaluations of irreducible components. Numerical values of the polynomial coefficients are determined for Rb atoms in their n 2S1 /2 , n 2P1 /2 ,3 /2 , n 2D3 /2 ,5 /2 , and n 2F5 /2 ,7 /2 Rydberg states of arbitrary high n . The transformation of the van der Waals interaction law -C6/R6 into the dipole-dipole law C3/R3 in the case of close dipole-connected two-atomic states (the Förster resonance) is considered and the dependencies on the magnetic quantum numbers M and on the angle θ of the constant C3(θ ;n l J M ) are determined together with the ranges of interatomic distances R , where the transformation appears.

  20. Der Einfluss der Digitalisierung auf die Organisation eines Unternehmens

    NASA Astrophysics Data System (ADS)

    Walter, Wolfram M.

    Die Digitalisierung schreitet mit großen Schritten voran. Dies wirkt sich nicht nur auf die Gesellschaft im Grundsatz, sondern auch auf das Verhalten der Kunden aus. Neue Kommunikationswege beschleunigen die Interaktion zwischen Unternehmen und Verbraucher. Im Vergleich mit großen Internetfirmen werden etablierte Dienstleistungsunternehmen - vom Energieversorger bis zu Versicherungen - stark unter Druck gesetzt, sich noch intensiver mit dem Kundenservice auseinanderzusetzen. Dies wird nur möglich sein, wenn sich die Organisationen entsprechend positionieren und sich frühzeitig auf die Veränderungen einstellen. Hieraus ergeben sich mehr Chancen als Risiken, zumal es nicht nur neue Prozesse, sondern auch neue Berufsbilder geben wird.

  1. Development of the Technique of Total Internal Reflection Microscopy and Measurement of the Van Der Waals Interaction Energy.

    NASA Astrophysics Data System (ADS)

    Walz, John Yokum

    The optical technique of Total Internal Reflection Microscopy (TIRM) has proven to be an effective tool for studying the interaction of a single, microscopic particle with a large planar surface. The technique utilizes the unique properties of an evanescent surface wave formed at the interface between two optically different media to measure the instantaneous separation distance of a particle from the interface. This thesis describes two major refinements to the TIRM technique. First, a geometric optics light scattering model was written to simulate the scattering of an evanescent wave by a microscopic dielectric sphere. The model is unique in that multiple reflections between the sphere and plate are included. The model predicts that for small polystyrene spheres (diameter <=q10 μm) in an aqueous medium, the simple exponential relationship between scattering intensity and separation distance, which was known to be valid at large distances, also holds down to contact. Experimental validation of the model with MgF_2-coated glass slides supports the model results. Second, a radiation pressure, or optical tweezers, technique was added to the TIRM apparatus. This technique involves use of a tightly focused laser beam, separate from that used to produce the evanescent wave, to exert a controllable force on the sphere. Through a linear momentum balance, this force is shown to contain both axial (parallel to incident beam) as well as radial (perpendicular to incident beam) components. The radial component allows holding a single particle at a fixed lateral position for an indefinite period against Brownian diffusion, which greatly facilitates measurements with TIRM. Finally, these two methods were used to measure the van der Waals attractive interaction energy between a 10 μm polystyrene sphere trapped in a secondary potential energy well above a sheet of cleaved mica. The measured interaction energies are found to be significantly less than those predicted with the

  2. van't Hoff-van der Waals osmotic pressure and energy transformers.

    PubMed

    Zener, C; Levenson, W

    1983-07-01

    We find the van't Hoff relations between osmotic pressure, freezing point depression, and boiling point elevation provide a clue on how, by using salt solutions, one may lower the cost of extracting power from low-grade heat sources. In particular, the ratio of 7 between the heat of evaporation and the heat of freezing of pure water suggests a chemical system that raises 7-fold the temperature difference between heat source and heat sink, while decreasing by the same factor the heat flux. Heat exchangers dominate the cost of heat engines operating upon low-grade heat. Their area for a fixed power output is inversely proportional to the available temperature differential. Herein lies the potential for a great cost reduction. We show that the simple van der Waals concept of a gas of hard elastic spheres suffices to understand the colligative properties of salt solutions, at least up to the concentration of the eutectic composition. This concept enables us to physically interpret the thermodynamic processes during the concentration of salt solutions by evaporation and during the mixing of ice and solid salt hydrates at their eutectic temperature. These are identical to the thermodynamic processes taking place during the isothermal compression and expansion of gases in pumps and in turbines.

  3. van't Hoff-van der Waals osmotic pressure and energy transformers

    PubMed Central

    Zener, Clarence; Levenson, William

    1983-01-01

    We find the van't Hoff relations between osmotic pressure, freezing point depression, and boiling point elevation provide a clue on how, by using salt solutions, one may lower the cost of extracting power from low-grade heat sources. In particular, the ratio of 7 between the heat of evaporation and the heat of freezing of pure water suggests a chemical system that raises 7-fold the temperature difference between heat source and heat sink, while decreasing by the same factor the heat flux. Heat exchangers dominate the cost of heat engines operating upon low-grade heat. Their area for a fixed power output is inversely proportional to the available temperature differential. Herein lies the potential for a great cost reduction. We show that the simple van der Waals concept of a gas of hard elastic spheres suffices to understand the colligative properties of salt solutions, at least up to the concentration of the eutectic composition. This concept enables us to physically interpret the thermodynamic processes during the concentration of salt solutions by evaporation and during the mixing of ice and solid salt hydrates at their eutectic temperature. These are identical to the thermodynamic processes taking place during the isothermal compression and expansion of gases in pumps and in turbines. PMID:16593343

  4. The potential for distributed generation in Japanese prototype buildings: A DER-CAM analysis of policy, tariff design, building energy use, and technology development (English Version)

    SciTech Connect

    Zhou, Nan; Marnay, Chris; Firestone, Ryan; Gao, Weijun; Nishida, Masaru

    2004-10-15

    The August 2003 blackout of the northeastern U.S. and CANADA caused great economic losses and inconvenience to New York City and other affected areas. The blackout was a warning to the rest of the world that the ability of conventional power systems to meet growing electricity demand is questionable. Failure of large power systems can lead to serious emergencies. Introduction of on-site generation, renewable energy such as solar and wind power and the effective utilization of exhaust heat is needed, to meet the growing energy demands of the residential and commercial sectors. Additional benefit can be achieved by integrating these distributed technologies into distributed energy resource (DER) systems. This work demonstrates a method for choosing and designing economically optimal DER systems. An additional purpose of this research is to establish a database of energy tariffs, DER technology cost and performance characteristics, and building energy consumption for Japan. This research builds on prior DER studies at the Ernest Orlando Lawrence Berkeley National Laboratory (LBNL) and with their associates in the Consortium for Electric Reliability Technology Solutions (CERTS) and operation, including the development of the microgrid concept, and the DER selection optimization program, the Distributed Energy Resources Customer Adoption Model (DER-CAM). DER-CAM is a tool designed to find the optimal combination of installed equipment and an idealized operating schedule to minimize a site's energy bills, given performance and cost data on available DER technologies, utility tariffs, and site electrical and thermal loads over a test period, usually an historic year. Since hourly electric and thermal energy data are rarely available, they are typically developed by building simulation for each of six end use loads used to model the building: electric-only loads, space heating, space cooling, refrigeration, water heating, and natural-gas-only loads. DER-CAM provides a

  5. Tycho Brahe - Instrumentenbauer und Meister der Beobachtungstechnik

    NASA Astrophysics Data System (ADS)

    Wolfschmidt, Gudrun

    Vor der Erfindung des Fernrohrs war der dänische Astronom Tycho Brahe (1546 - 1601) der bedeutendste beobachtende Astronom. Von seinem Observatorium Uraniborg auf der - damals dänischen - Insel Hven ist heute noch der Grundriß erkennbar, von Stjerneborg sind die Fundamente erhalten, die Kuppeln in den 1950er Jahren ergänzt. In der Astronomie-Ausstellung im Deutschen Museum gibt es ein Modell der Sternwarte Uraniborg und der zugehörigen Instrumente (Maßstab 1:10); das größere Modell wurde dem Technischen Museum in Malmö geschenkt. Die Instrumente, die er in den Observatorien Uraniborg und Stjerneborg benutzte, sind nicht erhalten. Aber es gibt gute Beschreibungen der Instrumente (Halbkreis, Quadranten, Sextanten, Armillarsphären, Triquetrum, Himmelsglobus) in seinem Buch Astronomiae instauratae mechanica (Wandsbek 1598). Eine Nachbildung des großen hölzernen Quadranten kann man im Runden Turm in Kopenhagen sehen. Zwei Sextanten, hergestellt für Tycho um 1600 von Jost Bürgi und Erasmus Habermel, gibt es noch im Nationalmuseum für Technik in Prag. Ähnlichkeiten von Tychos Instrumenten mit Groß-Instrumenten aus dem islamischen Kulturkreis sind auffällig. Tycho Brahes Meßgeräte markieren einen großen Fortschritt in der Entwicklung astronomischer Instrumente und Meßtechniken und bilden die Grundlage für den weiteren Fortschritt der Positionsastronomie und der damit verbundenen Tabellenwerke. Die Nachwirkungen sind bis ins 17. und 18. Jahrhundert nachweisbar.

  6. Control of Greenhouse Gas Emissions by Optimal DER Technology Investment and Energy Management in Zero-Net-Energy Buildings

    SciTech Connect

    Stadler, Michael; Siddiqui, Afzal; Marnay, Chris; Aki, Hirohisa; Lai, Judy

    2009-08-10

    The U.S. Department of Energy has launched the commercial building initiative (CBI) in pursuit of its research goal of achieving zero-net-energy commercial buildings (ZNEB), i.e. ones that produce as much energy as they use. Its objective is to make these buildings marketable by 2025 such that they minimize their energy use through cutting-edge, energy-efficiency technologies and meet their remaining energy needs through on-site renewable energy generation. This paper examines how such buildings may be implemented within the context of a cost- or CO2-minimizing microgrid that is able to adopt and operate various technologies: photovoltaic modules (PV) and other on-site generation, heat exchangers, solar thermal collectors, absorption chillers, and passive/demand-response technologies. A mixed-integer linear program (MILP) that has a multi-criteria objective function is used. The objective is minimization of a weighted average of the building's annual energy costs and CO2 emissions. The MILP's constraints ensure energy balance and capacity limits. In addition, constraining the building's energy consumed to equal its energy exports enables us to explore how energy sales and demand-response measures may enable compliance with the ZNEB objective. Using a commercial test site in northernCalifornia with existing tariff rates and technology data, we find that a ZNEB requires ample PV capacity installed to ensure electricity sales during the day. This is complemented by investment in energy-efficient combined heat and power (CHP) equipment, while occasional demand response shaves energy consumption. A large amount of storage is also adopted, which may be impractical. Nevertheless, it shows the nature of the solutions and costs necessary to achieve a ZNEB. Additionally, the ZNEB approach does not necessary lead to zero-carbon (ZC) buildings as is frequently argued. We also show a multi-objective frontier for the CA example, whichallows us to estimate the needed technologies

  7. Persönlichkeitsentwicklung als ziel der Bildung: Aus der Sicht eines Psychologen

    NASA Astrophysics Data System (ADS)

    Heinze, Burger

    1990-06-01

    Personality, which is a term almost always used in a positive sense, does not exist from the moment of birth, but it develops under the influence of heredity and environment. Adolescence, which is seen as a transition from childhood to adulthood, raises difficulties in many modern industrialized countries as a result of the often arduous search for individual identity. In this context identity is seen as an interaction between heredity and environment. While developing his own personality, the young person has to maintain an integral existence vis-à-vis himself, society and life. Psychology defines the personality as the sum of numerous psychological characteristics, through which differences between people are revealed. The development of these characteristics is to be seen in the environment, maturation and actions of the individual. It can be subdivided into causes, conditions and processes. Finally the article discusses various aspects of the general question of education. The author concludes that the development of the personality should be an aim of education, but that this aim is presently unattainable because of a lack of clarity in the concept of education.

  8. Ab initio intermolecular potential energy surfaces for the Ar-NCCN van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Solimannejad, Mohammad; Jouypazadeh, Hamidreza; Farrokhpour, Hossein

    2014-11-01

    The intermolecular potential energy surface of complex pairing argon with cyanogen molecule (NCCN) was calculated using the coupled cluster with single and double and perturbative triple excitations (CCSD(T)) with aug-cc-pvdz basis set extended with a set of mid-bond (3s3p2d1f1g) functions. The interaction energies were calculated by the supermolecular approach with the full counterpoise correction for the basis set superposition error. The calculated potential energies were fitted to an analytical expression. The calculated Ar-NCCN potential energy surface shows a global minimum at 3.35 Å, the distance between argon and centre of mass of cyanogen, for the T-shaped geometry and two local minimum at distance of 5.54 Å for the linear geometry on one side of cyanogen. Finally, the interaction second virial coefficients were calculated using the fitted potential energy surface and were compared with those obtained by the parameters of the Beattie-Bridgeman equation of states of pure argon and cyanogens fluids, approximately.

  9. Optimization of van der Waals Energy for Protein Side-Chain Placement and Design

    PubMed Central

    Fahmy, Amr; Wagner, Gerhard

    2011-01-01

    Computational determination of optimal side-chain conformations in protein structures has been a long-standing and challenging problem. Solving this problem is important for many applications including homology modeling, protein docking, and for placing small molecule ligands on protein-binding sites. Programs available as of this writing are very fast and reasonably accurate, as measured by deviations of side-chain dihedral angles; however, often due to multiple atomic clashes, they produce structures with high positive energies. This is problematic in applications where the energy values are important, for example when placing small molecules in docking applications; the relatively small binding energy of the small molecule is drowned by the large energy due to atomic clashes that hampers finding the lowest energy state of the docked ligand. To address this we have developed an algorithm for generating a set of side-chain conformations that is dense enough that at least one of its members would have a root mean-square deviation of no more than R Å from any possible side-chain conformation of the amino acid. We call such a set a side-chain cover set of order R for the amino acid. The size of the set is constrained by the energy of the interaction of the side chain to the backbone atoms. Then, side-chain cover sets are used to optimize the conformation of the side chains given the coordinates of the backbone of a protein. The method we use is based on a variety of dead-end elimination methods and the recently discovered dynamic programming algorithm for this problem. This was implemented in a computer program called Octopus where we use side-chain cover sets with very small values for R, such as 0.1 Å, which ensures that for each amino-acid side chain the set contains a conformation with a root mean-square deviation of, at most, R from the optimal conformation. The side-chain dihedral-angle accuracy of the program is comparable to other implementations; however

  10. Optimization of van der Waals energy for protein side-chain placement and design.

    PubMed

    Fahmy, Amr; Wagner, Gerhard

    2011-10-05

    Computational determination of optimal side-chain conformations in protein structures has been a long-standing and challenging problem. Solving this problem is important for many applications including homology modeling, protein docking, and for placing small molecule ligands on protein-binding sites. Programs available as of this writing are very fast and reasonably accurate, as measured by deviations of side-chain dihedral angles; however, often due to multiple atomic clashes, they produce structures with high positive energies. This is problematic in applications where the energy values are important, for example when placing small molecules in docking applications; the relatively small binding energy of the small molecule is drowned by the large energy due to atomic clashes that hampers finding the lowest energy state of the docked ligand. To address this we have developed an algorithm for generating a set of side-chain conformations that is dense enough that at least one of its members would have a root mean-square deviation of no more than R Å from any possible side-chain conformation of the amino acid. We call such a set a side-chain cover set of order R for the amino acid. The size of the set is constrained by the energy of the interaction of the side chain to the backbone atoms. Then, side-chain cover sets are used to optimize the conformation of the side chains given the coordinates of the backbone of a protein. The method we use is based on a variety of dead-end elimination methods and the recently discovered dynamic programming algorithm for this problem. This was implemented in a computer program called Octopus where we use side-chain cover sets with very small values for R, such as 0.1 Å, which ensures that for each amino-acid side chain the set contains a conformation with a root mean-square deviation of, at most, R from the optimal conformation. The side-chain dihedral-angle accuracy of the program is comparable to other implementations; however

  11. a Code for Automated Construction of Potential Energy Surfaces for Van Der Waals Systems

    NASA Astrophysics Data System (ADS)

    Quintas Sánchez, Ernesto; Dawes, Richard

    2017-06-01

    The potential energy surface (PES) constitutes a cornerstone for theoretical studies of spectroscopy and dynamics. We fit PESs using a local interpolating moving least squares (L-IMLS) approach. The L-IMLS method is interpolative and has the flexibility to fit energies or energies and gradients, where inclusion of gradient information significantly reduces the number of points required for an accurate fit. The method permits fully automated PES generation: beginning with an initial set of seed points, an automatic point selection scheme determines where new data are required and, in a series of iterations, computes new ab initio data and updates the fit until a specified accuracy is reached. We have interfaced this fitting approach to popular electronic structure codes such as Molpro and CFOUR to automatically generate ab initio 4D PESs for vdWs systems composed of two (rigid) linear fragments. We present here our freely distributed code designed to run in parallel on a computing cluster, allowing the user to specify the system (masses, interatomic equilibrium distances, symmetry, energy range of interest, etc.) through an input file. For a selection of benchmark systems, we show that PESs with fitting errors below 1 \\wn can be constructed using only a few hundred ab initio points. M. Majumder, S. Ndengue and R. Dawes, Molecular Physics 114, 1 (2016).

  12. Potential energy surface of the CO{sub 2}–N{sub 2} van der Waals complex

    SciTech Connect

    Nasri, Sameh; Ajili, Yosra; Jaidane, Nejm-Eddine; Kalugina, Yulia N.; Halvick, Philippe; Stoecklin, Thierry; Hochlaf, Majdi

    2015-05-07

    Four-dimensional potential energy surface (4D-PES) of the atmospherically relevant CO{sub 2}–N{sub 2} van der Waals complex is generated using the explicitly correlated coupled cluster with single, double, and perturbative triple excitation (CCSD(T)-F12) method in conjunction with the augmented correlation consistent triple zeta (aug-cc-pVTZ) basis set. This 4D-PES is mapped along the intermonomer coordinates. An analytic fit of this 4D-PES is performed. Our extensive computations confirm that the most stable form corresponds to a T-shape structure where the nitrogen molecule points towards the carbon atom of CO{sub 2}. In addition, we located a second isomer and two transition states in the ground state PES of CO{sub 2}–N{sub 2}. All of them lay below the CO{sub 2} + N{sub 2} dissociation limit. This 4D-PES is flat and strongly anisotropic along the intermonomer coordinates. This results in the possibility of the occurrence of large amplitude motions within the complex, such as the inversion of N{sub 2}, as suggested in the recent spectroscopic experiments. Finally, we show that the experimentally established deviations from the C{sub 2v} structure at equilibrium for the most stable isomer are due to the zero-point out-of-plane vibration correction.

  13. The CO-Ne van der Waals complex: ab initio intermolecular potential energy, interaction induced electric dipole moment and polarizability surfaces, and second virial coefficients.

    PubMed

    Baranowska, Angelika; Fernández, Berta; Rizzo, Antonio; Jansík, Branislav

    2009-11-14

    The intermolecular potential energy, interaction induced electric dipole moment and polarizability surfaces of the CO-Ne van der Waals complex are calculated using coupled cluster methods and the d-aug-cc-pVTZ basis set extended with a set of 3s3p2d1f1g midbond functions placed in the middle of the van der Waals bond. After fitting the interaction properties to appropriate analytical functions the surfaces are further used in semiclassical calculations of the pressure, the dielectric and the refractivity second virial coefficients of the system. The interaction potential energy surface has a single minimum (-49.9952 cm(-1)), which corresponds to R = 3.383 A and theta = 79.4 degrees. The computed dielectric second virial coefficient B(epsilon) approximately -0.27 cm(6) mol(-2) around the room temperature.

  14. Einsteins Spuren in den Archiven der Wissenschaft: Physikgeschichte

    NASA Astrophysics Data System (ADS)

    Marx, Werner

    2005-07-01

    Die Erwähnungen und Zitierungen von Einsteins Arbeiten dokumentieren lediglich den quantifizierbaren Anteil von Einsteins Beitrag zur Physik. Gleichwohl belegen sie die außergewöhnliche Resonanz und Langzeitwirkung seiner Arbeiten. Die Häufigkeit der Zitierungen entspricht nicht der allgemeinen Einschätzung ihrer Bedeutung. Insbesondere die Pionierarbeiten werden inzwischen als bekannt vorausgesetzt und nicht mehr explizit zitiert. Interessanterweise ist seine nach 1945 meist zitierte Arbeit nicht eine der Pionierarbeiten zur Quantenphysik oder Relativitätstheorie, sondern jene aus dem Jahr 1935 zum berühmten Einstein-Podolsky-Rosen-Paradoxon.

  15. Linear interaction energy models for beta-secretase (BACE) inhibitors: Role of van der Waals, electrostatic, and continuum-solvation terms.

    PubMed

    Tounge, Brett A; Rajamani, Ramkumar; Baxter, Ellen W; Reitz, Allen B; Reynolds, Charles H

    2006-05-01

    Computing the binding affinity of a protein-ligand complex is one of the most fundamental and difficult tasks in computer-aided drug design. Many approaches for computing binding affinities can be classified as linear interaction energy (LIE) models as they rely on some type of linear fit of computed interaction energies between ligand and protein. We have examined the computed interaction energies of a series of beta-secretase (BACE) inhibitors in terms of van der Waals, coulombic, and continuum-solvation contributions to ligand binding. We have also systematically examined the effect of different protonation states of the protein and ligands. We find that the binding affinities are relatively insensitive to the protonation state of the protein when neutral ligands are considered. Inclusion of charged ligands leads to large deviations in the coulomb, solvation, and even van der Waals terms. The latter is due to increased repulsive van der Waals interactions in the complex due to the strong coulomb attraction found between oppositely charged functional groups in the protein and ligand. In general, we find that the best models are obtained when the protein is judiciously charged (e.g. Asp32-, Arg235+) and the potentially charged ligands are treated as neutral.

  16. Darwin, Engels und die Rolle der Arbeit in der biologischen und kulturellen Evolution des Menschen

    NASA Astrophysics Data System (ADS)

    Reichholf, Josef H.

    Im Jahre 1876, 5 Jahre nach Erscheinen von Darwins Buch über die Evolution des Menschen und die sexuelle Selektion (Darwin 1871), veröffentlichte Friedrich Engels den berühmt gewordenen Essay "Anteil der Arbeit an der Menschwerdung des Affen“ (Engels 1876). Die Kernfrage darin lautet in Kurzform: Warum hat der Mensch eigentlich ein Bedürfnis nach Arbeit? Engels Antwort wird nachfolgend näher betrachtet und vom gegenwärtigen Kenntnisstand aus beurteilt. Wie sich zeigen wird, beantworten seine Überlegungen die Frage nicht wirklich. Sie ist weiterhin offen. Es können lediglich einige zusätzliche Anhaltspunkte zur Diskussion gestellt werden. Angesichts des drängenden Problems millionenfacher Arbeitslosigkeit und der Forderungen nach einem "Grundrecht auf Arbeit“ kommt den Überlegungen zum möglichen Ursprung des Bedürfnisses nach Arbeit mehr als nur akademisches Interesse zu.

  17. Quantum Effects in Cosmochemistry: Complexation Energy and Van Der Waals Radii

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Wilson, T. L.

    2007-01-01

    The subject of quantum effects in cosmochemistry was recently addressed with the goal of understanding how they contribute to Q-phase noble gas abundances found in meteorites. It was the pursuit of the Q-phase carrier of noble gases and their anomalous abundances that ultimately led to the identification, isolation, and discovery of presolar grains. In spite of its importance, Q-phase investigations have led a number of authors to reach conclusions that do not seem to be supported by quantum chemistry. In view of the subject's fundamental significance, additional study is called for. Two quantum properties of Q-phase candidates known as endohedral carbon-cage clathrates such as fullerenes will be addressed here. These are complexation energy and instability induced by Pauli blocking (exclusion principle).

  18. Nonlinear oscillation of nanoelectro-mechanical resonators using energy balance method: considering the size effect and the van der Waals force

    NASA Astrophysics Data System (ADS)

    Ghalambaz, Mohammad; Ghalambaz, Mehdi; Edalatifar, Mohammad

    2016-03-01

    The energy balance method is utilized to analyze the oscillation of a nonlinear nanoelectro-mechanical system resonator. The resonator comprises an electrode, which is embedded between two substrates. Two types of clamped-clamped and cantilever nano-resonators are studied. The effects of the van der Waals attractions, Casimir force, the small size, the fringing field, the mid-plane stretching, and the axial load are taken into account. The governing partial differential equation of the resonator is reduced using the Galerkin method. The energy method is applied to obtain an analytical solution without considering any linearization or small parameter. The results of the present study are compared with the results available in the literature. In addition, the results of the present analytical solution are compared with the Runge-Kutta numerical results. An excellent agreement between the present analytical solution, numerical solution, and the results available in the literature was found. The influences of the van der Waals force, Casimir force, size effect, and fringing field effect on the oscillation frequency of resonators are studied. The results indicate that the presence of the intermolecular forces (van der Waals), Casimir force, and fringing field effect decreases the oscillation frequency of the resonator. In contrast, the presence of the size effect increases the oscillation frequency of the resonator.

  19. Kommunikationsanforderungen an verteilte Echtzeitsysteme in der Fertigungsautomatisierung

    NASA Astrophysics Data System (ADS)

    Just, Roman; Trsek, Henning

    Kommunikationssysteme der Automatisierung müssen hohe zeitliche Anforderungen erfüllen, damit die entsprechenden industriellen Anwendungen realisiert werden können. Im Gegensatz zum IT-Bereich sind diese Anforderungen jedoch häufig nicht genau bekannt, was insbesondere beim Einsatz von drahtlosen Technologien Probleme bereiten kann1. In dieser Arbeit werden Verkehrsmuster einer realen Anlage aus dem Bereich der Fertigungsautomatisierung bestimmt. Die Zwischenankunfts- und Latenzzeiten einzelner Sensorund Aktorsignale ermöglichen Rückschlüsse auf zeitliche Anforderungen und Charakteristiken der untersuchten Anwendung. Im Anschluss werden die erzielten Erkenntnisse hinsichtlich ausgewählter Kommunikationsanforderungen analysiert und aktuell gültige Anforderungen von realen Automatisierungsanlagen abgeleitet. Weiterhin werden sie zukünftig zur Entwicklung realitätsnaher Simulationsmodelle genutzt.

  20. Computations of Lifshitz-van der Waals interaction energies between irregular particles and surfaces at all separations for resuspension modelling

    NASA Astrophysics Data System (ADS)

    Priye, Aashish; Marlow, William H.

    2013-10-01

    The phenomenon of particle resuspension plays a vital role in numerous fields. Among many aspects of particle resuspension dynamics, a dominant concern is the accurate description and formulation of the van der Waals (vdW) interactions between the particle and substrate. Current models treat adhesion by incorporating a material-dependent Hamaker's constant which relies on the heuristic Hamaker's two-body interactions. However, this assumption of pairwise summation of interaction energies can lead to significant errors in condensed matter as it does not take into account the many-body interaction and retardation effects. To address these issues, an approach based on Lifshitz continuum theory of vdW interactions has been developed to calculate the principal many-body interactions between arbitrary geometries at all separation distances to a high degree of accuracy through Lifshitz's theory. We have applied this numerical implementation to calculate the many-body vdW interactions between spherical particles and surfaces with sinusoidally varying roughness profile and also to non-spherical particles (cubes, cylinders, tetrahedron etc) orientated differently with respect to the surface. Our calculations revealed that increasing the surface roughness amplitude decreases the adhesion force and non-spherical particles adhere to the surfaces more strongly when their flatter sides are oriented towards the surface. Such practical shapes and structures of particle-surface systems have not been previously considered in resuspension models and this rigorous treatment of vdW interactions provides more realistic adhesion forces between the particle and the surface which can then be coupled with computational fluid dynamics models to improve the predictive capabilities of particle resuspension dynamics.

  1. Five-body van der Waals interactions

    NASA Astrophysics Data System (ADS)

    Han, Jianing

    2017-06-01

    We report on the five-body repulsive and attractive van der Waals interactions between the strongly dipole-dipole coupled Rydberg states. Compared to four-body van der Waals interactions, five-body van der Waals interactions show more energy levels and more potential wells caused by avoided crossings. This research bridges the few-body physics and many-body physics. Other disciplines, such as chemistry, biology, and medical fields, will also benefit from better understanding van der Waals interactions.

  2. C{sub 6}H{sub 6}/Au(111): Interface dipoles, band alignment, charging energy, and van der Waals interaction

    SciTech Connect

    Abad, E.; Martinez, J. I.; Flores, F.; Ortega, J.; Dappe, Y. J.

    2011-01-28

    We analyze the benzene/Au(111) interface taking into account charging energy effects to properly describe the electronic structure of the interface and van der Waals interactions to obtain the adsorption energy and geometry. We also analyze the interface dipoles and discuss the barrier formation as a function of the metal work-function. We interpret our DFT calculations within the induced density of interface states (IDIS) model. Our results compare well with experimental and other theoretical results, showing that the dipole formation of these interfaces is due to the charge transfer between the metal and benzene, as described in the IDIS model.

  3. Imaging van der Waals Interactions.

    PubMed

    Han, Zhumin; Wei, Xinyuan; Xu, Chen; Chiang, Chi-Lun; Zhang, Yanxing; Wu, Ruqian; Ho, W

    2016-12-15

    The van der Waals interactions are responsible for a large diversity of structures and functions in chemistry, biology, and materials. Discussion of van der Waals interactions has focused on the attractive potential energy that varies as the inverse power of the distance between the two interacting partners. The origin of the attractive force is widely discussed as being due to the correlated fluctuations of electron charges that lead to instantaneous dipole-induced dipole attractions. Here, we use the inelastic tunneling probe to image the potential energy surface associated with the van der Waals interactions of xenon atoms.

  4. Organe der Osmoregulation und Exkretion

    NASA Astrophysics Data System (ADS)

    Møbjerg, Nadja

    Die meisten Schädeltiere sind in der Lage, die Wasser- und Ionenkonzentration ihres Innenmilieus zu regulieren, sind also im Hinblick auf ihren Ionenhaushalt weitgehend unabhängig von der Umgebung. Sie halten die Konzentration von Wasser und anorganischen Ionen in ihren Körperflüssigkeiten (interstitielle Flüssigkeit und Blut) innerhalb enger Grenzen konstant (Osmoregulierer). Schleim aale (Myxinoida) können zwar die Konzentration einzelner anorganischer Ionen regulieren, sind aber insgesamt der hohen Osmolarität des Meerwassers angepasst, also isoosmostisch zu diesem. Isoosmotisch oder leic ht hyperosmostisch zur Umgebung sind auch marine Neoselachier und Latimeria chalumnae (Actinistia), die dazu organische Osmolyte (Harnstoff und Trimethylaminoxid) im Blut akkumulieren (Osmokonformer). Bei anderen aquatischen Schädeltieren sind die Körperflüssigkeiten zur Umgebung hypoosmotisch (im Meerwasser) — sie halten Wasser zurück und scheiden anorganiche Ionen aus — oder hyperosmotisch (im Süßwasser), indem sie Wasser abgeben und anorganische Ionen aufnehmen.

  5. High Energy Proton-Proton Elastic Scattering for Large Momentum Transfers and Van der Waals Type Model

    NASA Astrophysics Data System (ADS)

    Aleem, F.

    1980-03-01

    The most recent measurements of the angular distribution in proton-proton elastic scattering at sqrt{s}=27.4, 45 and 62GeV with squared four momentum transfer, -t, extending up to 14(GeV/c)2, have been explained using Van der Waals type model.

  6. Van der Waals Type Model and Structure in bar{p}p Elastic Scattering at High Energies

    NASA Astrophysics Data System (ADS)

    Aleem, F.

    1983-10-01

    The most recent measurements of the angular distribution for bar{p}p elastic scattering at pL=50, 100 and 200 GeV/ c which show a structure near -t=1.4 (GeV/ c)2, with squared four momentum transter -t extended to 5(GeV/ c)2, and the total cross section data for 50 <= pL <= 280GeV/ c have been simultaneously fitted by using the Van der Waals type model.

  7. Regenerative Energieträger im Aufwind: Entwicklung der erneuerbaren Energien

    NASA Astrophysics Data System (ADS)

    Kohl, Harald

    2006-05-01

    2005 kam 4,6 % des deutschen Primär-Energieverbrauchs aus erneuerbaren Energiequellen, bei der Stromproduktion lag ihr Anteil bei 10,2 %. Wesentliche Ursache ist der Boom bei der Windkraft, die vor allem durch Offshore-Windparks auf See weiter ausbaubar ist. Die Wasserkraft lieferte in Deutschland traditionell einen großen Beitrag zur Stromerzeugung, doch ihr Ausbaupotenzial ist gering. Die Photovoltaik, die solar- und die geothermische Stromerzeugung spielen derzeit noch eine kleine Rolle. Den deutschen Bedarf an Wärmeenergie deckten 2004 die erneuerbaren Energien zu 5,4 %, vor allem aus Biomasse. Die solarthermische Wärmeerzeugung hat sich gegenüber 2000 mehr als verdoppelt. Im Straßenverkehr spielen biogene Kraftstoffe mit 5,4 % noch eine untergeordnete Rolle. Bis 2050 könnte in Deutschland der Anteil regenerativer Energien am Primär-Energieverbrauch die Fünfzigprozentmarke überschreiten.

  8. Basis sets for the evaluation of van der Waals complex interaction energies: Ne-N2 intermolecular potential and microwave spectrum.

    PubMed

    Baranowska-Łączkowska, Angelika; Fernández, Berta

    2014-01-30

    In order to obtain efficient basis sets for the evaluation of van der Waals complex intermolecular potentials, we carry out systematic basis set studies. For this, interaction energies at representative geometries on the potential energy surfaces are evaluated using the CCSD(T) correlation method and large polarized LPol-n and augmented polarization-consistent aug-pc-2 basis sets extended with different sets of midbond functions. On the basis of the root mean square errors calculated with respect to the values for the most accurate potentials available, basis sets are selected for fitting the corresponding interaction energies and getting analytical potentials. In this work, we study the Ne-N2 van der Waals complex and after the above procedure, the aug-pc-2-3321 and the LPol-ds-33221 basis set results are fitted. The obtained potentials are characterized by T-shaped global minima at distances between the Ne atom and the N2 center of mass of 3.39 Å, with interaction energies of -49.36 cm(-1) for the aug-pc-2-3321 surface and -50.28 cm(-1) for the LPol-ds-33221 surface. Both sets of results are in excellent agreement with the reference surface. To check the potentials further microwave transition frequencies are calculated that agree well with the experimental and the aV5Z-33221 values. The success of this study suggests that it is feasible to carry out similar accurate calculations of interaction energies and ro-vibrational spectra at reduced cost for larger complexes than has been possible hitherto.

  9. Two-atom interaction energies with one atom in an excited state: van der Waals potentials versus level shifts

    NASA Astrophysics Data System (ADS)

    Donaire, M.

    2016-05-01

    I revisit the problem of the interaction between two dissimilar atoms with one atom in an excited state, recently addressed by Berman [Phys. Rev. A 91, 042127 (2015), 10.1103/PhysRevA.91.042127], Donaire et al. [Phys. Rev. Lett. 115, 033201 (2015), 10.1103/PhysRevLett.115.033201], and Milonni and Rafsanjani [Phys. Rev. A 92, 062711 (2015), 10.1103/PhysRevA.92.062711], for which precedent approaches have given conflicting results. In the first place, I discuss to what extent these works provide equivalent results. I show that the phase-shift rate of the two-atom wave function computed by Berman, the van der Waals potential of the excited atom by Donaire et al., and the level shift of the excited atom by Milonni and Rafsanjani possess equivalent expressions in the quasistationary approximation. In addition, I show that the level shift of the ground-state atom computed by Milonni and Rafsanjani is equivalent to its van der Waals potential. A diagrammatic representation of all those quantities is provided. The equivalences among them are, however, not generic. In particular, it is found that for the case of the interaction between two identical atoms excited, the phase-shift rate and the van der Waals potentials differ. Concerning the conflicting results of previous approaches in regards to the spatial oscillation of the interactions, I conclude, in agreement with Berman and with Milonni and Rafsanjani, that they refer to different physical quantities. The impacts of free-space dissipation and finite excitation rates on the dynamics of the potentials are analyzed. In contrast with Milonni and Rafsanjani, the oscillatory versus monotonic spatial forms of the potentials of each atom are found not to be related to the reversible versus irreversible nature of the excitation transfer involved.

  10. Quantenphysikalischer Ursprung der Eichidee

    NASA Astrophysics Data System (ADS)

    Bopp, Fritz

    Vergleichbares leisten.Tatsächlich folgt die EQE aus einer bereits vorhandenen, wenn auch wenig beachteten Symmetrie der empirisch bewährten Diractheorie. Sie ist darum einerseits im Sinne der Newtonschen Definition des Begriffs hypothesenfrei. Andererseits kann sie wegen der erforderlichen Phaseninvarianz kaum wegdiskutiert werden, was immer sie am Ende bedeuten mag. Die Erfindung neuer Symmetrien und die Anerkennung einer Unzahl unabhängiger Spinorkomponenten ist jedenfalls zunächst entbehrlich.Translated AbstractThe Quantum Physical Origin of the Gauge IdeaTo consider quantum physics as an interplay of creation and annihilation processes has the consequence that gauge field theories are not only possible but necessary. Since the complex conjugate phase factors of each pair of fermion creators and annihilators can be arbitrary chosen, quantum field theories must be completely phase invariant.Unfortunately, even globally the Dirac equation for systems of free fermions is not phase invariant. The Dirac matrices are namely transformed, if we multiply the spinor components by different constant phase factors. The Dirac equations before and after the transformation are however physically equivalent. We may therefore say: Systems of free fermions will be completely described, only if we consider the class of all equivalent Dirac equations.Since Dirac's commutation relations are unitarily invariant, the class equivalent Dirac equations is invariant under all transformations of the group U 4. Unitary diagonal matrices yield arbitrary phase transformations. Hence, gauge fields of the group U 4 are compatible with the postulate of general phase invariance. These gauge file are so similar to the QED that we may speak of an extended quantum electrodynamics, EQE.Here, we will show that EQE exists. The invariant subgroup U 1 U 4 yields QED. The complementary subgroup SU 4 includes four subgroups SU 3, there subgroups O 4

  11. Die Digitalisierung der Energiewirtschaft: Potenziale und Herausforderungen der IKT-Branche für Utility 4.0

    NASA Astrophysics Data System (ADS)

    Aichele, Christian; Schönberger, Marius

    Energieunternehmen haben auf dem Weg zur digitalen Transformation noch viele Herausforderungen zu bewältigen. Ein besonderer Schwerpunkt liegt derzeit auf der Modernisierung der IT-Systeme. Ausgangspunkt hierzu ist, dass sich bei den Endkonsumenten Mobile Applikationen, Smartphones, Tablet-PCs oder Smart TVs einer immensen Beliebtheit erfreuen. Durch diese Technologien wird die physische und virtuelle Welt in immer weiter zunehmendem Maße miteinander verknüpft. Mobile Applikation können einen wahren Hype hervorrufen und Verhaltensweisen auch nachhaltig verändern (ein Beispiel hierfür ist Pokémon Go, eine App die ein virtuelles Spiel mit der realen Umgebung kombiniert und die erstmalig auch eingefleischte Zocker aus der Anonymität ihrer häuslichen Umgebung hervorlocken konnte und für analoge Bewegung im Freien sorgte).

  12. Van der Waals quintessence stars

    SciTech Connect

    Lobo, Francisco S. N.

    2007-01-15

    The van der Waals quintessence equation of state is an interesting scenario for describing the late universe, and seems to provide a solution to the puzzle of dark energy, without the presence of exotic fluids or modifications of the Friedmann equations. In this work, the construction of inhomogeneous compact spheres supported by a van der Waals equation of state is explored. These relativistic stellar configurations shall be denoted as van der Waals quintessence stars. Despite of the fact that, in a cosmological context, the van der Waals fluid is considered homogeneous, inhomogeneities may arise through gravitational instabilities. Thus, these solutions may possibly originate from density fluctuations in the cosmological background. Two specific classes of solutions, namely, gravastars and traversable wormholes are analyzed. Exact solutions are found, and their respective characteristics and physical properties are further explored.

  13. Ab initiointermolecular potential energy surface of Ne···NCCN van der Waals complex: effect of the place of midbond function on the interaction

    NASA Astrophysics Data System (ADS)

    Solimannejad, Mohammad; Jouypazadeh, Hamidreza; Farrokhpour, Hossein

    2015-11-01

    The intermolecular potential energy surface of Ne...NCCN van der Waals complex was evaluated in the framework of the counterpoise-corrected supermolecular approach using CCSD(T) level and aug-cc-pVDZ basis set extended with a set of midbond (3s3p2d1f1g) functions. The effect of the place of midbond function on the accuracy of the calculated potential energy surface was examined and the optimised position for placing midbond function was determined. The calculated potential energy surface was fitted by an analytical function. The analytical function of intermolecular potential energy surface of Ne...NCCN demonstrated a global minimum energy of -12.024 meV related to the T-shape geometry at the distance between Ne and the centre of mass of NCCN of 3.28 Å. Finally, the interaction second virial coefficients (B12) of Ne and NCCN were calculated and used to calculate the second virial coefficients for the mixture of neon and cyanogen gases at different mole fractions of Ne gas.

  14. Amplituden der Kernphasen im Bereich der Kaustik B und Untersuchung der Struktur der Übergangszone zum inneren Erdkern mit spektralen Amplituden der diffraktierten Phase PKP(BC)

    NASA Astrophysics Data System (ADS)

    Wolf, Michael D. C.

    2002-04-01

    Das Ziel dieser Arbeit ist es, die Strukturen im äueren Erdkern zu untersuchen und Rückschlüsse auf die sich daraus ergebenden Konsequenzen für geodynamische Modellvorstellungen zu ziehen. Die Untersuchung der Kernphasenkaustik B mit Hilfe einer kumulierten Amplituden-Entfernungskurve ist Gegenstand des ersten Teils. Dazu werden die absoluten Amplituden der PKP-Phasen im Entfernungsbereich von 142 ° bis 147 ° bestimmt und mit den Amplituden synthetischer Seismogramme verglichen. Als Datenmaterial dienen die Breitbandregistrierungen des Deutschen Seismologischen Re-gionalnetzes (GRSN 1 ) und des Arrays Gräfenberg (GRF). Die verwendeten Wellen-formen werden im WWSSN-SP-Frequenzbereich gefiltert. Als Datenbasis dienen vier Tiefherdbeben der Subduktionszone der Neuen Hebriden (Vanuatu Island) und vier Nuklearexplosionen, die auf dem Mururoa und Fangataufa Atoll im Südpazifik stattgefunden haben. Beide Regionen befinden sich vom Regionalnetz aus gesehen in einer Epizentraldistanz von ungefähr 145 °. Die Verwendung eines homogen instrumentierten Netzes von Detektoren und die Anwendung von Stations- und Magnitudenkorrekturen verringern den Hauptteil der Streuung bei den Amplitudenwerten. Dies gilt auch im Vergleich zu Untersuchungen von langperiodischen Amplituden im Bereich der Kernphasenkaustik (Häge, 1981). Ein weiterer Grund für die geringe Streuung ist die ausschlieliche Verwendung von Ereignissen mit kurzer impulsiver Herdzeitfunktion. Erst die geringe Streuung der Amplitudenwerte ermöglicht eine Interpretation der Daten. Die theoretischen Amplitudenkurven der untersuchten Erdmodelle zeigen im Bereich der Kaustik B einen gleichartigen Kurvenverlauf. Bei allen Berechnungen wird ein einheitliches Modell für die Güte der P- und S-Wellen verwendet, das sich aus den Q-Werten der Modelle CIT112 und PREM 2 zusammensetzt. Die mit diesem Q-Modell berechneten Amplituden liegen in geringem Mae oberhalb der gemessenen Amplituden. Dies braucht nicht ber

  15. Umsetzung der Unternehmensstrategie mit der Balanced Scorecard

    NASA Astrophysics Data System (ADS)

    Crespo, Isabel; Bergmann, Lars; Portmann, Stefan; Lacker, Thomas; Lacker, Michael; Fleischmann, Jürgen; Kozó, Hans

    Die Balanced Scorecard (BSC) ist ein Ansatz zum strategischen Management, der neben der Ausrichtung des Unternehmens auf finanzielle Zielwerte ebenso großes Gewicht auf so genannte weiche Faktoren legt, die den wirtschaftlichen Erfolg eines Unternehmens erst ermöglichen. Das entscheidende Merkmal der Balanced Scorecard ist dabei, dass sie ein ausgewogenes System strategischer Ziele herstellt, welches das Unternehmen hinsichtlich der vier Perspektiven Finanzen, Kunden, interne Prozesse und Mitarbeiter und Potenziale strategisch ausrichtet (Kaplan u. Norton 1997).

  16. Einstellung und Wissen von Lehramtsstudierenden zur Evolution - ein Vergleich zwischen Deutschland und der Türkei

    NASA Astrophysics Data System (ADS)

    Graf, Dittmar; Soran, Haluk

    Es wird eine Untersuchung vorgestellt, in der Wissen und Überzeugungen von Lehramtsstudierenden aller Fächer zum Thema Evolution an zwei Universitäten in Deutschland und der Türkei erhoben worden sind. Die Befragung wurde in Dortmund und in Ankara durchgeführt. Es stellte sich heraus, dass ausgeprägte Defizite im Verständnis der Evolutionsmechanismen herrschen. Viele Studierende, insbesondere aus der Türkei, sind nicht von der Faktizität der Evolution überzeugt. Dies gilt sowohl für Studierende mit Fach Biologie als auch für Studierende mit anderen Fächern. Näher untersucht worden sind die Faktoren, die die Überzeugungen zur Evolution beeinflussen können, was ja in Anbetracht der hohen Ablehnungsrate der Evolution von besonderem Interesse ist. Das Vertrauen in die Wissenschaft spielt hierbei eine besondere Rolle: Wer der Wissenschaft vertraut, ist auch eher von der Evolution überzeugt, als diejenigen, die skeptisch gegenüber der Wissenschaft sind.

  17. Density functional theory with an approximate kinetic energy functional applied to study structure and stability of weak van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Wesołowski, T. A.; Ellinger, Y.; Weber, J.

    1998-04-01

    In view of further application to the study of molecular and atomic sticking on dust particles, we investigated the capability of the "freeze-and-thaw" cycle of the Kohn-Sham equations with constrained electron density (KSCED) to describe potential energy surfaces of weak van der Waals complexes. We report the results obtained for C6H6⋯X (X=O2, N2, and CO) as test cases. In the KSCED formalism, the exchange-correlation functional is defined as in the Kohn-Sham approach whereas the kinetic energy of the molecular complex is expressed differently, using both the analytic expressions for the kinetic energy of individual fragments and the explicit functional of electron density to approximate nonadditive contributions. As the analytical form of the kinetic energy functional is not known, the approach relies on approximations. Therefore, the applied implementation of KSCED requires the use of an approximate kinetic energy functional in addition to the approximate exchange-correlation functional in calculations following the Kohn-Sham formalism. Several approximate kinetic energy functionals derived using a general form by Lee, Lee, and Parr [Lee et al., Phys. Rev. A. 44, 768 (1991)] were considered. The functionals of this type are related to the approximate exchange energy functionals and it is possible to derive a kinetic energy functional from an exchange energy functional without the use of any additional parameters. The KSCED interaction energies obtained using the PW91 [Perdew and Wang, in Electronic Structure of Solids '91, edited by P. Ziesche and H. Eschrig (Academie Verlag, Berlin, 1991), p. 11] exchange-correlation functional and the kinetic energy functional derived from the PW91 exchange functional agree very well with the available experimental results. Other considered functionals lead to worse results. Compared to the supermolecule Kohn-Sham interaction energies, the ones derived from the KSCED calculations depend less on the choice of the

  18. Schlüsselkomponenten für Roboter in der Produktion Roboterhaut und Sicherheitskonzept für die Mensch-Roboter Kooperation

    NASA Astrophysics Data System (ADS)

    Denkena, B.; Hesse, P.; Friederichs, J.; Wedler, A.

    Vorgestellt wird der Aufbau einer aktiven Sensor-Matrix zur Abstands- und Kontaktdetektion in der Robotik. Diese besteht aus einem Sensornetzwerk zur Fusion und Überlagerung differenter physikalischer Wirkprinzipien. Die Sicherheit der I2C-Bus Kommunikation, der Aufbau der Roboterhaut, Ergebnisse der Abstandsdetektion mit Infrarot-, und Ultraschallsensorik werden dargestellt. Ferner wurden Temperatur-, und Beschleunigungssensoren auf die Oberfläche der Roboterhaut aufgebracht um Informationen über die Umgebung sicher an ein übergeordnetes Leitsystem zu übertragen. Eine unterlagerte sichere Roboterhaut mit Kontaktdetektion zeigt als einfache Schlüsselkomponente ein analoges Ausschaltverhalten für geringe Latenzzeiten. Als Schluss wird auf den Einsatz an einem Industrieroboter in der Produktion ohne trennende Schutzeinrichtungen (OTS) eingegangen.

  19. Kosmische Katastrophen und der Ursprung der Religion.

    NASA Astrophysics Data System (ADS)

    Hoyle, F.

    This book is a German translation, by V. Delavre, from the English original "The origin of the Universe and the origin of religion", published in 1993. Contents: E. Sens: Die unterbrochene Musikstunde. Einleitung zur deutschen Ausgabe. C. Ryskamp: Einführung. R. N. Anshen: Vorwort. F. Hoyle: Kosmische Katastrophen und der Ursprung der Religion - Die Folgen der Respektabilität; Eiszeiten und Kometen; Die allgemeine Situation in den Nacheiszeiten; Kometen und der Ursprung der Religionen; Der Übergang zu Mittelalter und Neuzeit. Diskussionsbeiträge: Ruth Nanda Anshen, Freeman Dyson, Paul Oscar Kristeller, John Archibald Wheeler, James Schwartz, Roger Shinn, Milton Gatch, Philip Solomon, Norman Newell. F. Hoyle: Schlußwort. A. Tollmann: Nachwort zur deutschen Ausgabe.

  20. Die Deutsche Statistische Gesellschaft in der Weimarer Republik und während der Nazidiktatur

    NASA Astrophysics Data System (ADS)

    Wilke, Jürgen

    Nach anfänglichen Schwierigkeiten durch den 1. Weltkrieg erlangte die Deutsche Statistische Gesellschaft (DStatG) unter dem renommierten Statistiker und Vorsitzenden der DStatG, Friedrich Zahn, durch eine Vielzahl von Aktivitäten hohes Ansehen. Es gab Bestrebungen, Statistiker aus allen Arbeitsfeldern der Statistik in die DStatG zu integrieren, wobei die "Mathematische Statistik" nur zögerlich akzeptiert wurde (Konjunkturforschung, Zeitreihenanalyse). Nach der Machtübernahme 1933 durch Adolf Hitler geriet die DStatG in das Fahrwasser nationalsozialistischer Ideologie und Politik (Führerprinzip, Gleichschaltung des Vereinswesens). Damit war eine personelle Umstrukturierung in der DStatG verbunden. Politisch Missliebige und rassisch Verfolgte mussten die DStatG verlassen (Bernstein, Freudenberg, Gumbel u.a.). Unter den Statistikern gab es alle Abstufungen im Verhalten zum Regime von Ablehnung und zwangsweiser Anpassung über bereitwilliges Mitläufertum bis zu bewusster Täterschaft. Besonders die Bevölkerungsstatistik wurde durch die NS- Rassenpolitik auf lange Sicht diskreditiert. Im Rahmen von Wirtschaftsplanung und Aufrüstung wurden neue zukunftsträchtige statistische Modelle (Grünig, Bramstedt, Leisse) entwickelt.

  1. Infrared detection and photon energy up-conversion in graphene layer infrared photodetectors integrated with LEDs based on van der Waals heterostructures: Concept, device model, and characteristics

    NASA Astrophysics Data System (ADS)

    Ryzhii, V.; Otsuji, T.; Ryzhii, M.; Karasik, V. E.; Shur, M. S.

    2017-09-01

    We propose the concept of the infrared detection and photon energy up-conversion in the devices using the integration of the graphene layer infrared detectors (GLIPs) and the light emitting diodes (LEDs) based on van der Waals (vdW) heterostructures. Using the developed device model of the GLIP-LEDs, we calculate their characteristics. The GLIP-LED devices can operate as the detectors of far- and mid infrared radiation (FIR and MIR) with an electrical output or with near-infrared radiation (NIR) or visible radiation (VIR) output. In the latter case, GLIP-LED devices function as the photon energy up-converters of FIR and MIR to NIR or VIR. The operation of GLIP-LED devices is associated with the injection of the electron photocurrent produced due to the interband absorption of the FIR/MIR photons in the GLIP part into the LED emitting NIR/VIR photons. We calculate the GLIP-LED responsivity and up-conversion efficiency as functions the structure parameters and the energies of the incident FIR/MIR photons and the output NIR/VIR photons. The advantages of the GLs in the vdW heterostructures (relatively high photoexcitation rate from and low capture efficiency into GLs) combined with the reabsorption of a fraction of the NIR/FIR photon flux in the GLIP (which can enable an effective photonic feedback) result in the elevated GLIP-LED device responsivity and up-conversion efficiency. The positive optical feedback from the LED section of the device lead to increasing current injection enabling the appearance of the S-type current-voltage characteristic with a greatly enhanced responsivity near the switching point and current filamentation.

  2. Theoretical studies for the N{sub 2}–N{sub 2}O van der Waals complex: The potential energy surface, intermolecular vibrations, and rotational transition frequencies

    SciTech Connect

    Zheng, Rui; Zheng, Limin; Yang, Minghui E-mail: yangmh@wipm.ac.cn; Lu, Yunpeng E-mail: yangmh@wipm.ac.cn

    2015-10-21

    Theoretical studies of the potential energy surface (PES) and bound states are performed for the N{sub 2}–N{sub 2}O van der Waals (vdW) complex. A four-dimensional intermolecular PES is constructed at the level of single and double excitation coupled-cluster method with a non-iterative perturbation treatment of triple excitations [CCSD(T)] with aug-cc-pVTZ basis set supplemented with bond functions. Two equivalent T-shaped global minima are located, in which the O atom of N{sub 2}O monomer is near the N{sub 2} monomer. The intermolecular fundamental vibrational states are assigned by inspecting the orientation of the nodal surface of the wavefunctions. The calculated frequency for intermolecular disrotation mode is 23.086 cm{sup −1}, which is in good agreement with the available experimental data of 22.334 cm{sup −1}. A negligible tunneling splitting with the value of 4.2 MHz is determined for the ground vibrational state and the tunneling splitting increases as the increment of the vibrational frequencies. Rotational levels and transition frequencies are calculated for both isotopomers {sup 14}N{sub 2}–N{sub 2}O and {sup 15}N{sub 2}–N{sub 2}O. The accuracy of the PES is validated by the good agreement between theoretical and experimental results for the transition frequencies and spectroscopic parameters.

  3. Akustikgestaltung in der Fahrzeugentwicklung

    NASA Astrophysics Data System (ADS)

    Pletschen, Bernd

    Die zielgerichtete Entwicklung der Fahrzeugakustik stellt eine hochkomplexe, integrative Aufgabenstellung im Rahmen der Fahrkomfortgestaltung des Automobils dar. Die Wahrnehmung der Komforteigenschaften eines Fahrzeugs erfolgt grundsätzlich als Wahrnehmung der Wirkung dieser Eigenschaften über einen oder mehrere Wahrnehmungskanäle des Menschen: visuell, auditiv, haptisch, olfaktorisch. Die individuelle Wahrnehmung ist hierbei subjektiv und daher mit rein physikalisch objektiven Messgrößen allein nur unvollständig zu beschreiben. Sie hängt einerseits von den Eigenschaften des betrachteten Fahrzeugs oder einer erlebten Situation ab und andererseits außerdem von der Sozialisation des Bewertenden und der Umgebung, in der die Bewertung stattfindet (Wikipedia). Der Fahrkomfort, den ein Fahrzeug Fahrer und Beifahrern bietet, wird also wegen unterschiedlicher Erwartungen des Kunden in den verschiedenen Weltmärkten sehr unterschiedlich erlebt.

  4. Sitzungsberichte der Heidelberger Akademie der Wissenschaften> " Jahrgang 1990 Sitzungsber.Heidelberg 90 " "Gott hat die Natur einfältig gemacht, sie aber suchen viel Künste"

    NASA Astrophysics Data System (ADS)

    Zehe, Horst

    Der Aufsatz demonstriert anhand ausgiebig kommentierter zeitgenössischer Zeugnisse Goethes Reaktion auf die Arbeiten Fraunhofers, insbesondere auf die Entdeckung der dunklen Linien im Sonnenspektrum. Den Fehlurteilen Goethes werden dabei die Urteile zeitgenössischer Physiker wie Chladni und J.F.W. Herschel gegenübergestellt. Bislang noch ungedruckte Dokumente aus dem Weimarer Goethe- und Schiller-Archiv belegen, daß sich Goethe nicht nur literarisch mit Fraunhofer beschäftigte, sondern daß er auch dessen Versuche mit Hilfe des Jenaer Universitätsmechanikers Körner getreulich zu wiederholen suchte.

  5. Ionization spectroscopies and theoretical calculations of cis and trans 3-fluoro-N-methylaniline-Arn(n = 1,2) van der Waals clusters: Structures and binding energies

    NASA Astrophysics Data System (ADS)

    Zhang, Lijuan; Li, Dazhi; Cheng, Min; Du, Yikui; Zhu, Qihe

    2017-08-01

    The ab initio and dispersion-corrected density functional theory (DFT) calculations of the van der Waals (vdW) clusters of cis and trans 3-fluoro-N-methylaniline-Arn (3FNMA-Arn) (n = 1,2) predict that, for cis and trans 3FNMA-Ar1 clusters, the π-bound geometry with the Ar atom sitting over the ring is the global minimum in both neutral and cationic states, while for cis and trans 3FNMA-Ar2 clusters, the [π | π]-bound sandwich structure with two Ar ligands occupying nearly equivalent π-bound positions above and below the ring plane is the global minimum. The vibronic spectra of cis and trans 3FNMA-Ar1 clusters in the S1 state were recorded by using one-color and two-color resonant two-photon ionization (R2PI) techniques, the comparison of which yields an estimate of the binding energy of cluster in the S1 state. It is found that the linear correlation between the redshift of the S1 ← S0 electronic transition energy (E1) of cluster and the E1 of the monomer also holds for the Ar clusters of hetero-di-substituted aromatics. By recording the photoionization efficiency (PIE) curves and mass-analyzed threshold ionization (MATI) dissociation spectra of cis and trans 3FNMA-Ar1 clusters, the ionization energies (IE) and binding energies of clusters in the D0 state are obtained. The MATI spectra of the cis and trans 3FNMA-Ar1 cations exhibit significant progressions of the vdW bending mode (bx), indicating the structural changes of the clusters in the bending coordinate upon ionization. The combination of the three kinds of spectroscopic methods provides the binding energies of cis and trans 3FNMA-Ar1 clusters in the S0, S1 and D0 states with good accuracy, and the values estimated by dispersion-corrected DFT calculations compare well with the experimental results. From our studies, the ωB97X-D and TD-ωB97X-D methods using high quality basis set are recommended for studying the intermolecular interaction of such vdW clusters in the ground and excited states.

  6. Ionization spectroscopies and theoretical calculations of cis and trans 3-fluoro-N-methylaniline-Arn(n=1,2) van der Waals clusters: Structures and binding energies.

    PubMed

    Zhang, Lijuan; Li, Dazhi; Cheng, Min; Du, Yikui; Zhu, Qihe

    2017-08-05

    The ab initio and dispersion-corrected density functional theory (DFT) calculations of the van der Waals (vdW) clusters of cis and trans 3-fluoro-N-methylaniline-Arn (3FNMA-Arn) (n=1,2) predict that, for cis and trans 3FNMA-Ar1 clusters, the π-bound geometry with the Ar atom sitting over the ring is the global minimum in both neutral and cationic states, while for cis and trans 3FNMA-Ar2 clusters, the [π|π]-bound sandwich structure with two Ar ligands occupying nearly equivalent π-bound positions above and below the ring plane is the global minimum. The vibronic spectra of cis and trans 3FNMA-Ar1 clusters in the S1 state were recorded by using one-color and two-color resonant two-photon ionization (R2PI) techniques, the comparison of which yields an estimate of the binding energy of cluster in the S1 state. It is found that the linear correlation between the redshift of the S1←S0 electronic transition energy (E1) of cluster and the E1 of the monomer also holds for the Ar clusters of hetero-di-substituted aromatics. By recording the photoionization efficiency (PIE) curves and mass-analyzed threshold ionization (MATI) dissociation spectra of cis and trans 3FNMA-Ar1 clusters, the ionization energies (IE) and binding energies of clusters in the D0 state are obtained. The MATI spectra of the cis and trans 3FNMA-Ar1 cations exhibit significant progressions of the vdW bending mode (bx), indicating the structural changes of the clusters in the bending coordinate upon ionization. The combination of the three kinds of spectroscopic methods provides the binding energies of cis and trans 3FNMA-Ar1 clusters in the S0, S1 and D0 states with good accuracy, and the values estimated by dispersion-corrected DFT calculations compare well with the experimental results. From our studies, the ωB97X-D and TD-ωB97X-D methods using high quality basis set are recommended for studying the intermolecular interaction of such vdW clusters in the ground and excited states. Copyright

  7. Calculation of the structure, potential energy surface, vibrational dynamics, and electric dipole properties for the Xe:HI van der Waals complex.

    PubMed

    Preller, M; Grunenberg, J; Bulychev, V P; Bulanin, M O

    2011-05-07

    We report the structure and spectroscopic characteristics for the Xe:HI van der Waals binary isomers determined from variational solutions of two-dimensional and three-dimensional (3D) vibrational Schrödinger equations. The solutions are based on a potential energy surface computed at the coupled-cluster level of theory including single and double excitations and a non-iterative perturbation treatment of triple excitations [CCSD(T)]. The dipole moment surface was calculated using quadratic configuration interaction (QCISD). The global potential minimum is shown to be located at the anti-hydrogen-bonded Xe-IH isomer, 21 cm(-1) below the secondary local minimum associated with the hydrogen-bonded Xe-HI isomeric form. The dissociation energy from the global minimum is 245.9 cm(-1). 3D Schrödinger equations are solved for the rotational quantum numbers J = k = 0, 1, and 2, without invoking an adiabatic separation of high- and low-frequency degrees of freedom. The vibrational ground state resides in the Xe-HI potential well, while the first excited state, 8.59 cm(-1) above the ground, occupies the Xe-IH well. We find that intra-complex dynamics exhibits a sudden transformation upon increase of the r(HI) bond length, accompanied by abrupt changes in the geometric and dipole parameters. A similar chaotic behavior is predicted to occur for Xe:DI at a shorter r(DI) bond length, which implies stronger coupling between low- and high-frequency motions in the heavier complex. Our calculations confirm a strong enhancement for the r(HI) stretch fundamental and a significant weakening for the first overtone vibrational transitions in Xe:HI, as compared to those in the free HI molecule. A qualitative explanation of this, earlier experimentally detected effect is suggested.

  8. The HCO{sup +}–H{sub 2} van der Waals interaction: Potential energy and scattering

    SciTech Connect

    Massó, H.; Wiesenfeld, L.

    2014-11-14

    We compute the rigid-body, four-dimensional interaction potential between HCO{sup +} and H{sub 2}. The ab initio energies are obtained at the coupled-cluster single double triple level of theory, corrected for Basis Set Superposition Errors. The ab initio points are fit onto the spherical basis relevant for quantum scattering. We present elastic and rotationally inelastic coupled channels scattering between low lying rotational levels of HCO{sup +} and para-/ortho-H{sub 2}. Results are compared with similar earlier computations with He or isotropic para-H{sub 2} as the projectile. Computations agree with earlier pressure broadening measurements.

  9. Zweiwegintegration durch zweisprachige Bildung? Ergebnisse aus der Staatlichen Europa-Schule Berlin

    NASA Astrophysics Data System (ADS)

    Meier, Gabriela

    2012-06-01

    While there is no simple recipe of how to respond to the multitude of languages present in many European schools, this article presents a promising alternative to monolingual education. The focus is on Staatliche Europa-Schule Berlin (SESB), a two-way immersion (TWI) model that unites children whose mother tongue is German with children whose mother tongue is another locally spoken language in one class and teaches them together in two languages. Thus in this model, offered by 17 primary schools and 13 secondary schools in Berlin, pupils learn in two languages from and with each other. Based on a largely quantitative, quasi-experimental study with 603 students, evidence is provided that there are a number of peace-linguistic benefits that can promote two-way social integration, besides fostering personal and societal multilingualism. This suggests that TWI education as practised in Berlin could serve as an educational model for other multilingual parts of Europe.

  10. Drei neue gamma-Doradus-Sterne aus der ASAS-3 Datenbank

    NASA Astrophysics Data System (ADS)

    Bernhard, Klaus; Huemmerich, Stefan

    2016-02-01

    By analysis of data from the ASAS-3 archive, the stars HD 18011, NSV 16873 and NSV 3272 were identified as multiperiodic gamma Doradus variables. Essential information on these variables is presented, along with unwhitened frequency spectra and statistically significant frequencies, as derived with Period 04.

  11. Thaumatelsonella kingelepha, eine neue Gattung und Art aus der Antarktis (Crustacea: Amphipoda: Gammaridea: Stenothoidae)

    NASA Astrophysics Data System (ADS)

    Rauschert, M.; Andres, H. G.

    1991-03-01

    A taxonomic study on stenothoid amphipods from the area of South Shetland Islands (Antarctica), led to the description of Thaumatelsonella kingelepha gen. and sp. nov. The systematic position of Pseudothaumatelson cyproides Nicholls, 1938 is discussed, as the redescription by Bellan-Santini & Ledoyer (1986) based on the first recovery of that species included differences from the diagnosis of the genus.

  12. Adsorption and desorption of propane on Pd (111): A van der Waals density functional study. Energy binding sites and geometries

    NASA Astrophysics Data System (ADS)

    e Silva, Tadeu Leonardo Soares; Schmal, Martin

    2017-10-01

    Palladium supported catalysts used for the partial oxidation of propane reaction aiming the H2 production deserves specific characterizations and theoretical modeling for the explanation of the transition phase and energy needed for the adsorption and desorption of propane on top of the palladium atoms. On the other hand, the product distribution will depend on the adsorption and desorption capacity of the different compounds present during the reaction. In this work, the adsorption of propane on a Pd (111) surface was studied by using different approximations. A periodic method based on the Density Functional Theory (DFT) formalism employing vdW-DF functional was investigated for determining preferred binding sites of propane on palladium. The results show that the adsorption on hcp site is more stable than on top site and predictions fit well the experimental results.

  13. Zu einer inhaltsorientierten Theorie des Lernens und Lehrens der biologischen Evolution

    NASA Astrophysics Data System (ADS)

    Wallin, Anita

    Der Zweck dieser Studie (zwecks Überblick siehe dazu Abb. 9.1) war zu untersuchen, wie die Schüler der Sekundarstufe II ein Verständnis von der Theorie der biologischen Evolution entwickeln. Vom Ausgangspunkt "Vorurteile der Schüler“ ausgehend wurden Unterrichtssequenzen entwickelt und drei verschiedene Lernexperimente in einem zyklischen Prozess durchgeführt. Das Wissen der Schüler wurde vor, während und nach den Unterrichtssequenzen mit Hilfe von schriftlichen Tests, Interviews und Diskussionsrunden in kleinen Gruppen abgefragt. Etwa 80 % der Schüler hatten vor dem Unterricht alternative Vorstellungen von Evolution, und in dem Nachfolgetest erreichten circa 75 % ein wissenschaftliches Niveau. Die Argumentation der Schüler in den verschiedenen Tests wurde sorgfältig unter Rücksichtnahme auf Vorurteile, der konzeptionellen Struktur der Theorie der Evolution und den Zielen des Unterrichts analysiert. Daraus konnten Einsichten in solche Anforderungen an Lehren und Lernen gewonnen werden, die Herausforderungen an Schüler und Lehrer darstellen, wenn sie anfangen, evolutionäre Biologie zu lernen oder zu lehren. Ein wichtiges Ergebnis war, dass das Verständnis existierender Variation in einer Population der Schlüssel zum Verständnis von natürlicher Selektion ist. Die Ergebnisse sind in einer inhaltsorientierten Theorie zusammengefasst, welche aus drei verschiedenen Aspekten besteht: 1) den inhaltsspezifischen Aspekten, die einzigartig für jedes wissenschaftliche Feld sind; 2) den Aspekten, die die Natur der Wissenschaft betreffen; und 3) den allgemeinen Aspekten. Diese Theorie kann in neuen Experimenten getestet und weiter entwickelt werden.

  14. Die Arbeitsunfähigkeit in der Statistik der GKV

    NASA Astrophysics Data System (ADS)

    Busch, Klaus

    Der vorliegende Beitrag gibt anhand der Statistiken des Bundesministeriums für Gesundheit (BMG) einen Überblick über die Arbeitsunfähigkeitsdaten der Gesetzlichen Krankenkassen (GKV). Zunächst werden die Arbeitsunfähigkeitsstatistiken der Krankenkassen und die Erfassung der Arbeitsunfähigkeit erläutert. Hiernach wird auf die Entwicklung der Fehlzeiten auf GKV-Ebene eingegangen. Ebenfalls wird Bezug auf die Unterschiede der Fehlzeiten zwischen den verschiedenen Kassen genommen.

  15. Ancillary Services Provided from DER

    SciTech Connect

    Campbell, J.B.

    2005-12-21

    Distributed energy resources (DER) are quickly making their way to industry primarily as backup generation. They are effective at starting and then producing full-load power within a few seconds. The distribution system is aging and transmission system development has not kept up with the growth in load and generation. The nation's transmission system is stressed with heavy power flows over long distances, and many areas are experiencing problems in providing the power quality needed to satisfy customers. Thus, a new market for DER is beginning to emerge. DER can alleviate the burden on the distribution system by providing ancillary services while providing a cost adjustment for the DER owner. This report describes 10 types of ancillary services that distributed generation (DG) can provide to the distribution system. Of these 10 services the feasibility, control strategy, effectiveness, and cost benefits are all analyzed as in the context of a future utility-power market. In this market, services will be provided at a local level that will benefit the customer, the distribution utility, and the transmission company.

  16. Untersuchung von Methoden zur ldentifikation der zeit und frequenzabhangigen Netzimpedanz (Investigation of Methods for the Identification of Time and Frequency dependent Network Impedances) Impedances

    DTIC Science & Technology

    2016-10-01

    Wissenschaftlicher Tatigkeitsnachweis 169 vii Nomenklatur Verwendete Abki.irzungen AAF AC ADC CAD DC DFT DNL DPLL DSP DUT EE EEA EEG EMV...Gesetz ( EEG ) von 2000 [BGBIOO] und dessen Novellierungen [BGB104),[BGB108],[BGB111],[BGB112] [BGB114] ein rasanter Ausbau der EE bei der...Elektroenergieversorgung eingeleitet. Das EEG garantiert eine bevorzugte Netzeinspeisung mit festen Vergiitungssiitzen fur die Stromerzeugung aus erneuerbaren

  17. Approximation dreidimensionaler Oberflächenmodelle der Lippen-Kiefer-Gaumen-Region durch aktive Polygonnetze

    NASA Astrophysics Data System (ADS)

    Weichert, Frank; Ewerlin, Christoph; Büttner, Christian; Shamaa, Ali; Landes, Constantin; Linder, Roland; Wagner, Mathias

    In dieser Arbeit wird ein Verfahren zur Rekonstruktion eines dreidimensionalen Oberflächenmodells aus Serienschnitten vorgestellt, die sich von Lippen-Kiefer-Gaumenspalten (kurz LKG) ableiten und insbesondere die in der chirurgischen Behandlung relevanten medizinischen Strukturen berücksichtigen. Die Intention ist, ein aktives Polygonnetz (deformierbares Oberflächennetz) zur Rekonstruktion der Struktur zu verwenden. Initial wird ein Netzprototyp als grobe Approximation der Struktur erstellt und dann mithilfe eines Gradient Vector Flow (GVF)-Kraftfeldes deformiert. Inhärenter Aspekt der Deformation ist die Beachtung eines resultierenden überschneidungsfreien Oberflächennetzes. Die rekonstruierte Oberfläche eignet sich aufgrund ausgezeichneter Eigenschaften als Eingabe für eine Kräftesimulation mittels Finite-Elemente-Methoden.

  18. Kants Theorie der Sonne: Physikgeschichte

    NASA Astrophysics Data System (ADS)

    Jacobi, Manfred

    2005-01-01

    Im Rahmen seiner Kosmogonie entwickelte der junge Immanuel Kant eine Theorie der Sonne. Sie ist ein einzigartiges Zeugnis seiner intuitiven Vorstellungskraft und beweist auch die Leistungsfähigkeit der damaligen, vorwiegend von Newton geprägten Weltsicht. Entstehung, Aufbau und Dynamik der Sonne werden in Kants Theorie ebenso erklärt wie etwa das Phänomen der Sonnenflecken.

  19. Plasmakristalle an Bord der ISS: Komplexe Plasmen in Schwerelosigkeit

    NASA Astrophysics Data System (ADS)

    Thomas, Hubertus M.; Morfill, Gregor E.

    2005-03-01

    Das deutsch-russische Experiment PKE-Nefedov erforscht komplexe Plasmen in Schwerelosigkeit. Seit 2001 arbeitet es auf der internationalen Raumstation ISS. Komplexe Plasmen bestehen aus einem teilweise ionisierten Gas, das Mikropartikel enthält. Diese Partikel laden sich im Strom der Elektronen und Ionen elektrisch auf. Ihr Verhalten beeinflussen vor allem abgeschirmte Coulomb-Kräfte und Reibungskräfte im Gas. Sie können sich sogar zu einem Plasma-Kristall anordnen. Diese reguläre, dreidimensionale Struktur hat viele Eigenschaften eines echten Kristallgitters. Sie ist jedoch makroskopisch, also klassisch, und die einzelnen Partikel sind viel besser beobachtbar als etwa Atome in kondensierter Materie. Das macht sie zu idealen Modellsystemen für die Erforschung von Kristallen, Phasenübergängen oder von Flüssigkeiten. Komplexe Plasmen zeigen darüber hinaus ganz neue Eigenschaften.

  20. Zeitspiel ist keine Alternative - Warum der Wandel zur Pflicht wird

    NASA Astrophysics Data System (ADS)

    Dieper, Stephan

    "Wege entstehen dadurch, dass man sie geht." (Franz Kafka) Die Welt der Digitalisierung ist voll von Wegen, die jemand gegangen ist, bevor dort ein Weg war. Manche dieser Wege stellten sich als Sackgasse heraus, manche als Abkürzung und aus anderen wurden ganze Wegenetze und Städte. Die Energiewelt wird durch den digitalen Wandel nicht verschont bleiben. Durch die intelligenten Messsysteme und die zugehörigen, neuen Strukturen werden energiefremden Wettbewerbern Chancen zum Markteintritt eröffnet. EVUs müssen sich darauf einstellen, dass der permanente Wandel nicht mehr enden wird. Doch auch den EVUs eröffnen sich Optionen. Um erfolgreich zu sein, müssen sie lernen loszugehen, ohne das genaue Ziel zu kennen.

  1. Herschel und die Zukunft der Fern-Infrarot-Astronomie

    NASA Astrophysics Data System (ADS)

    Linz, Hendrik

    2015-06-01

    Schon lange ist die beobachtende Astronomie den engen Grenzen des optisch Sichbaren entwachsen und hat fast alle Bereiche des elektromagnetischen Spektrums für sich dienstbar gemacht. Im sogenannten nahen und mittleren Infrarot (Wellenlängen zwischen 1-30 μm) sowie im Millimeter- und Radio-Regime (Wellenlängen zwischen 1 mm und 10 m) ist die Erdatmosphäre relativ gut durchlässig für elektromagnetische Signale oder hat zumindest eine Vielzahl von spektral begrenzten Transmissionsfenstern, die astronomische Beobachtungen zumindest von höheren Bergen aus möglich machen. Allerdings ist das sogenannte Ferne Infrarot (FIR, 30-300 μm Wellenlänge) von der Erde aus fast völlig unzugänglich für astronomische Beobachtungen. Selbst für die besten Beobachtungsplätze der Erde bleibt die atmosphärische Transmission durch die immense Wasserdampf- Absorption auf ein absolutes Minimum beschränkt. Jedoch erlaubt uns das FIR Zugang zu Informationen, die sehr nützlich sind für die astrophysikalische Forschung und komplementär zu anderen Wellenlängen-Bereichen.

  2. Die Kosmologie der Griechen.

    NASA Astrophysics Data System (ADS)

    Mittelstraß, J.

    Contents: 1. Mythische Eier. 2. Thales-Welten. 3. "Alles ist voller Götter". 4. Griechische Astronomie. 5. "Rettung der Phänomene". 6. Aristotelische Kosmololgie. 7. Aristoteles-Welt und Platon-Welt. 8. Noch einmal: die Göttlichkeit der Welt. 9. Griechischer Idealismus.

  3. B-Zell-Lymphome der Haut - Pathogenese, Diagnostik und Therapie.

    PubMed

    Nicolay, Jan P; Wobser, Marion

    2016-12-01

    Primär kutane B-Zell-Lymphome (PCBCL) beschreiben reifzellige lymphoproliferative Erkrankungen der B-Zell-Reihe, die primär die Haut betreffen. Die Biologie und der klinische Verlauf der einzelnen PCBCL-Subtypen variieren untereinander stark und unterscheiden sich grundsätzlich von primär nodalen und systemischen B-Zell-Lymphomen. Primär kutane Marginalzonenlymphome (PCMZL) und primäre kutane follikuläre Keimzentrumslymphome (PCFCL) werden auf Grund ihres unkomplizierten Verlaufs und ihrer exzellenten Prognose zu den indolenten PCBCL gezählt. Demgegenüber stellen die diffus großzelligen B-Zell-Lymphome, hauptsächlich vom Beintyp (DLBCL, LT) die aggressiveren PCBCL-Varianten mit schlechterer Prognose dar. Für die Ausbreitungsdiagnostik und die Therapieentscheidung sind eine genaue histologische und immunhistochemische Klassifizierung sowie der Ausschluss einer systemischen Beteiligung in Abgrenzung zu nodalen oder systemischen Lymphomen notwendig. Die Diagnostik sollte dabei durch molekularbiologische Untersuchungen unterstützt werden. Therapeutisch stehen für die indolenten PCBCL primär operative und radioonkologische Maßnahmen im Vordergrund sowie eine Systemtherapie mit dem CD20-Antikörper Rituximab bei disseminiertem Befall. Die aggressiveren Varianten sollten in erster Linie mit Kombinationen aus Rituximab und Polychemotherapieschemata wie z. B. dem CHOP-Schema oder Modifikationen davon behandelt werden. Auf Grund der in allen seinen Einzelheiten noch nicht vollständig verstandenen Pathogenese und Biologie sowie des begrenzten Therapiespektrums der PCBCL besteht hier, speziell beim DLBCL, LT, noch erheblicher Forschungsbedarf. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  4. Sitzungsberichte der Heidelberger Akademie der Wissenschaften¬Jahrgang 1990 Sitzungsber.Heidelberg 90¬"Gott hat die Natur einfältig gemacht, sie aber suchen viel Künste"

    NASA Astrophysics Data System (ADS)

    Zehe, Horst

    Der Aufsatz demonstriert anhand ausgiebig kommentierter zeitgenössischer Zeugnisse Goethes Reaktion auf die Arbeiten Fraunhofers, insbesondere auf die Entdeckung der dunklen Linien im Sonnenspektrum. Den Fehlurteilen Goethes werden dabei die Urteile zeitgenössischer Physiker wie Chladni und J.F.W. Herschel gegenübergestellt. Bislang noch ungedruckte Dokumente aus dem Weimarer Goethe- und Schiller-Archiv belegen, daß sich Goethe nicht nur literarisch mit Fraunhofer beschäftigte, sondern daß er auch dessen Versuche mit Hilfe des Jenaer Universitätsmechanikers Körner getreulich zu wiederholen suchte.

  5. Arzt und Hobby-Astronom in stürmischen Zeiten Der Büchernachlass des Doktor Johannes Häringshauser, Viertelsmedicus in Mistelbach (1630-1641) in der Melker Stiftsbibliothek.

    NASA Astrophysics Data System (ADS)

    Davison, Giles; Glaßner, Gottfried

    2009-06-01

    Auf der Suche nach astronomischer Literatur stieß Giles Davison in der Melker Stiftsbibliothek auf den Namen "Doctor Johannes Häringshauser“ als Besitzer seltener und interessanter astronomischer Werke u.a. von Johannes Regiomontan, Georg von Peuerbach, Michael Mästlin, Johannes Kepler und Daniel Sennert. Weitere in den Jahren 2007-2009 durchgeführte Nachforschungen ergaben, dass es sich um den von 1630-1641 in Mistelbach, Niederösterreich, als Landschaftsarzt tätigen Vater des Melker Konventualen und Bibliothekars Sigismund Häringshauser (1631-1698) handelt. Er wurde 1603 als Sohn des aus Magdeburg stammenden Apothekers Johannes Häringshauser geboren und starb 1642 in Mistelbach. Johannes Häringshauser Sen. bekleidete von 1613-1640 eine Reihe wichtiger Ämter in der Wiener Stadtregierung und starb 1647. Der Studienaufenthalt von Dr. Johannes Häringshauser Jun. in Padua (1624-1626) dürfte das Interesse für Astronomie geweckt haben, das sich in seiner in die Bestände der Melker Stiftsbibliothek eingegangenen Privatbibliothek widerspiegelt. Der Großteil der 10 dem Fachbereich der Astronomie und Astrologie zuzuweisenden Titel wurde von ihm in den Jahren 1636 und 1637 erworben.

  6. Lineare und verzweigte Blockcopolymere aus Polypeptiden und synthetischen Polymeren

    NASA Astrophysics Data System (ADS)

    Kukula, Hildegard

    2001-07-01

    Die vorliegende Arbeit beschäftigt sich mit der Synthese und den Eigenschaften von linearen und verzweigten amphiphilen Polypeptid-Blockcopolymeren. Die Frage nach dem Einfluss der Topologie und Konformation der Blockcopolymere auf die supramolekularen und kolloidalen Eigenschaften bildete einen wichtigen Aspekt bei den Untersuchungen. Die Blockcopolymere wurden nach einem mehrstufigen Reaktionsschema durch Kombination von anionischer und ringöffnender Polymerisation von Aminosäuren-N-Carboxyanhydriden (NCA) synthetisiert. Die Untersuchung der Polypeptid-Blockcopolymere hinsichtlich ihres Aggregationsverhaltens in fester Phase sowie in verdünnter wässriger Lösung erfolgte mittels Streumethoden (SAXS, WAXS, DLS) sowie abbildender Methoden (TEM). Durch Einsatz der Blockcopolymere als polymere Stabilisatoren in der Emulsionspolymerisation wurden Oberflächen funktionalisierte Latizes erhalten. Als Beispiel für eine pharmazeutische Anwendung wurden bioverträgliche Polypeptid-Blockcopolymere als Wirkstoff-Trägersysteme in der Krebstherapie eingesetzt. This work describes the synthesis and characterization of linear and branched polypeptide block copolymers having amphiphilic character. The studies focused on the impact of the block copolymers' conformation and architecture on the supramolecular and colloidal properties. The polypeptide block copolymers were prepared in a multi-step process involving the anionic synthesis of (poly)amino-functional polymers (polystyrene and polybutadiene) which where used as macroinitiators for the ring-opening polymerization of N-carboxyanhydrides (NCA) of protected a-aminoacids. Supramolecular structures of the block copolymers in the solid state as well as in diluted aqueous solution were investigated using scattering (SAXS, WAXS, DLS) and microscopic (TEM) methods. Both linear and branched polypeptide block copolymers were used as polymeric stabilizers in the emulsion polymerization of styrene to yield polypeptide

  7. Note on a van der Waals Gas.

    ERIC Educational Resources Information Center

    Bauman, Robert P.; Harrison, Joseph G.

    1996-01-01

    Discusses the difficulties with the standard model for introduction of attractive forces into the van der Waals equation. Presents an analysis in terms of force and time delays and an alternative analysis for more advanced students in terms of energy. (JRH)

  8. Molekulare Methoden zum Nachweis, zur Quantifizierung und zum Monitoring der Mykotoxinbildung lebensmittelrelevanter Pilze

    NASA Astrophysics Data System (ADS)

    Geisen, Rolf

    Schimmelpilze kommen ubiquitär vor und spielen besonders bei pflanzlichen Lebensmitteln und Rohprodukten eine besondere Rolle als Verderbsorganismen. Es wird geschätzt, dass 20-25 % der jährlichen Produktion an pflanzlichen Produkten durch Schimmelpilze verdorben werden (Smith et al., 1994). Viele der lebensmittelrelevanten Schimmelpilze sind zudem in der Lage, Mykotoxine, toxische Sekundärmetabolite, zu bilden, was das Ausmaß des Problems deutlich macht. Die wichtigsten mykotoxinbildenden Spezies gehören zu den Fusarien (Trichothecene, Fumonisine, Zearalenon), Aspergillen (Aflatoxin, Ochratoxin, Cyclopiazonsäure) und Penicillien (Patulin, Ochratoxin). Für viele Mykotoxine, wie die Aflatoxine, Ochratoxin, Fumonisine und Trichothecene sind Grenzwerte erlassen worden, die die Verkehrsfähigkeit betroffener Produkte regeln. Die Einhaltung der Grenzwerte kann sehr genau durch offizielle chemisch-analytische Methoden, wie HPLC, GC-MS etc. kontrolliert werden. Diese analytischen Methoden sind aber für die Anwendung eines HACCP-Ansatzes zur Kontrolle der Mykotoxinbildung nur bedingt geeignet, da sie Endpunktkontrollen darstellen und nur das über eine längere Zeit gebildete Mykotoxin bestimmen. Sie sagen daher nichts über die biologischen Bedingungen zur Zeit der Bildung durch den Pilz aus.

  9. Mathematik in der Drahtlosen Kommunikation

    NASA Astrophysics Data System (ADS)

    Boche, Holger; Eisenblätter, Andreas

    Die Mobilkommunikation besitzt heute große wirtschaftliche Bedeutung. Sie hat seit der Einführung des derzeit noch dominierenden Mobilfunkstandards GSM Anfang der neunziger Jahre einen enormen Einfluss auf das gesellschaftliche Leben genommen. Mit neuen Anwendungsfeldern, z. B. im Maschinen- und Anlagenbau, in der Automobilindustrie und im Wohnbereich, wird die Bedeutung der Mobilkommunikation weiter steigen. Um der Vielfalt der Anwendungen gerecht zu werden und die Wünsche nach neuen Diensten erfüllen zu können, werden fortwährend neue Mobilfunksysteme eingeführt.

  10. Flexible DER Utility Interface System: Final Report, September 2004--May 2006

    SciTech Connect

    Lynch, J.; John, V.; Danial, S. M.; Benedict, E.; Vihinen, I.; Kroposki, B.; Pink, C.

    2006-08-01

    In an effort to accelerate deployment of Distributed Energy Resources (DER) such as wind, solar, and conventional backup generators to our nation's electrical grid, Northern Power Systems (NPS), the California Energy Commission (CEC), and the National Renewable Energy Laboratory (NREL) collaborated to create a prototype universal interconnect device called the DER Switch.

  11. Grundbegriffe der Thermodynamik

    NASA Astrophysics Data System (ADS)

    Heintze, Joachim

    In diesem Kapitel geht es darum, Vorgänge zu analysieren, bei denen der thermische Zustand eines Systems verändert wird: Daher der Name "Thermodynamik". Wir werden zunächst untersuchen, unter welchen Umständen man eine Zustandsänderung im Detail beschreiben kann. Hierbei werden wir zwei grundsätzlich verschiedene Arten, Zustandsänderungen herbeizuführen, kennenlernen: reversible und irreversible Prozesse. Sodann werden wir die Eigenschaften von Zustandsgrößen allgemein definieren und dabei auf eine überaus wichtige neue Zustandsgröße, die Entropie, stoßen.

  12. Impact of axillary ultrasound (AUS) on axillary dissection in breast conserving surgery (BCS).

    PubMed

    Reyna, Chantal; Kiluk, John V; Frelick, Anne; Khakpour, Nazanin; Laronga, Christine; Lee, Marie Catherine

    2015-06-01

    Preoperative axillary ultrasound (AUS) in clinically node-negative patients may increase axillary lymph node dissection (ALND) in ACoSOG Z0011-eligible patients. We hypothesize that AUS identifies operative axillary disease (>3 positive nodes) in women undergoing breast conserving surgery (BCS). After IRB approval, a retrospective review of female breast cancer patients was performed; patients with clinical T1/T2 tumors undergoing BCS were included. Clinical, radiologic, and pathologic data were collected. Of 139 eligible subjects, 119/139 (86%) had nonpalpable axillary nodes. 47/119 patients (40%) had abnormal AUS and 15/47 (32%) had a positive FNA. Fourteen had ALND ;10/14 (71%) had >3 positive nodes. 6/32 (18%) with abnormal AUS but FNA negative were sentinel lymph node (SLN) positive. Of 72 normal AUS, 15 (22%) were SLN positive; 9/15 (60%) had ALND; 1 (11%) had >3 positive nodes. When evaluating for >3 positive nodes, AUS plus FNA had a sensitivity of 91%, specificity of 95%, NPV of 99%, and PPV of 71%. AUS/FNA has a high NPV for axillary metastasis and remarkable sensitivity for three or more positive axillary nodes, therefore AUS-identified metastasis should be treated as clinically node-positive disease, and is appropriate even in patients planning breast conserving surgery. © 2015 Wiley Periodicals, Inc.

  13. CAD in der Praxis

    NASA Astrophysics Data System (ADS)

    Labisch, Susanna

    Konstruktion und Fertigung erfolgen in der Praxis fast ausschließlich rechnerunterstützt. Mit diesem Rechnereinsatz beim Konstruieren (CAD, Computer Aided Design) und Fertigen CAM (Computer Aided Manufacturing) scheint die technische Zeichnung an Bedeutung zu verlieren, da die Verständigung zwischen Konstruktions- und Fertigungsabteilung primär durch den Austausch digitaler Daten erfolgen kann.

  14. Berechnung des Hochfrequenzverhaltens komplexer Strukturen mit der Methode gekoppelter Streuparameter - CSC

    NASA Astrophysics Data System (ADS)

    Glock, H.-W.; Rothemund, K.; van Rienen, U.

    2004-05-01

    Es wird eine Methode zur Berechnung der Hochfrequenz-Eigenschaften komplexer Strukturen vorgestellt. Das Verfahren beruht auf der Zerlegung der Gesamtstruktur in einzelne einfachere Segmente, deren breitbandige S-Matrizen mit kommerziellen Programmen berechnet werden. Das Gesamtsystem kann von beliebiger Topologie sein, und die Zahl der die Segmente verkoppelnden Hohlleiter- Moden ist nicht begrenzt. Als Ergebnis steht bei offenen Strukturen deren vollständige S-Matrix, bei abgeschlossenen deren Resonanzeigenschaften zur Verfügung. Die theoretischen Grundlagen werden beschrieben und die Anwendung mit Beispielen aus dem Gebiet der Teilchenbeschleuniger und zu Eigenschaften schwach elliptisch geformter Resonatoren illustriert. A method called Coupled S-Parameter Calculation - CSC is described which is used to calculate the rf properties of complex structures, i.e. either their scattering (devices with ports) or their resonance properties. The method is based on the segmentation of the entire system into sections being less complex, the external calculation of the section’s broadband S-matrices, and a combination scheme, which is applicable to any topology and number of modes. The method’s principle is described. Examples from the field of particle accelerator cavities and about the properties of weakly elliptical resonators are given.

  15. A new potential energy surface for OH(A 2Σ+)-Kr: the van der Waals complex and inelastic scattering.

    PubMed

    Chadwick, H; Brouard, M; Chang, Y-P; Eyles, C J; Perkins, T; Seamons, S A; Kłos, J; Alexander, M H; Aoiz, F J

    2012-10-21

    New ab initio studies of the OH(A(2)Σ(+))-Kr system reveal significantly deeper potential energy wells than previously believed, particularly for the linear configuration in which Kr is bound to the oxygen atom side of OH(A(2)Σ(+)). In spite of this difference with previous work, bound state calculations based on a new RCCSD(T) potential energy surface yield an energy level structure in reasonable accord with previous studies. However, the new calculations suggest the need for a reassignment of the vibrational levels of the electronically excited complex. Quantum mechanical and quasi-classical trajectory scattering calculations are also performed on the new potential energy surface. New experimental measurements of rotational inelastic scattering cross sections are reported, obtained using Zeeman quantum beat spectroscopy. The values of the rotational energy transfer cross sections measured experimentally are in good agreement with those derived from the dynamical calculations on the new adiabatic potential energy surface.

  16. Isotope separation by photodissociation of Van der Waal's molecules

    DOEpatents

    Lee, Yuan T.

    1977-01-01

    A method of separating isotopes based on the dissociation of a Van der Waal's complex. A beam of molecules of a Van der Waal's complex containing, as one partner of the complex, a molecular species in which an element is present in a plurality of isotopes is subjected to radiation from a source tuned to a frequency which will selectively excite vibrational motion by a vibrational transition or through electronic transition of those complexed molecules of the molecular species which contain a desired isotope. Since the Van der Waal's binding energy is much smaller than the excitational energy of vibrational motion, the thus excited Van der Waal's complex dissociate into molecular components enriched in the desired isotope. The recoil velocity associated with vibrational to translational and rotational relaxation will send the separated molecules away from the beam whereupon the product enriched in the desired isotope can be separated from the constituents of the beam.

  17. An exchange-Coulomb model potential energy surface for the Ne-CO interaction. I. Calculation of Ne-CO van der Waals spectra.

    PubMed

    Dham, Ashok K; McCourt, Frederick R W; Meath, William J

    2009-06-28

    Exchange-Coulomb model potential energy surfaces have been developed for the Ne-CO interaction. The initial model is a three-dimensional potential energy surface based upon computed Heitler-London interaction energies and literature results for the long-range induction and dispersion energies, all as functions of interspecies distance, the orientation of CO relative to the interspecies axis, and the bond length of the CO molecule. Both a rigid-rotor model potential energy surface, obtained by setting the CO bond length equal to its experimental spectroscopic equilibrium value, and a vibrationally averaged model potential energy surface, obtained by averaging the stretching dependence over the ground vibrational motion of the CO molecule, have been constructed from the full data set. Adjustable parameters in each model potential energy surface have been determined through fitting a selected subset of pure rotational transition frequencies calculated for the (20)Ne-(12)C(12)O isotopolog to precisely known experimental values. Both potential energy surfaces provide calculated results for a wide range of available experimental microwave, millimeter-wave, and midinfrared Ne-CO transition frequencies that are generally far superior to those obtained using the best current literature potential energy surfaces. The vibrationally averaged CO ground state potential energy surface, employed together with a potential energy surface obtained from it by replacing the ground vibrational state average of the CO stretching dependence of the potential energy surface by an average over the first excited CO vibrational state, has been found to be particularly useful for computing and/or interpreting mid-IR transition frequencies in the Ne-CO dimer.

  18. A quantum chemistry study of the van der Waals dimers of benzene, naphthalene, and anthracene: Crossed (D{sub 2d}) and parallel-displaced (C{sub 2h}) dimers of very similar energies in the linear polyacenes

    SciTech Connect

    Gonzalez, C.; Lim, E.C.

    2000-04-06

    A quantum chemistry study of the ground-state structures and binding energies of the van der Waals dimers of benzene, naphthalene, and anthracene has been made at the MP2/6-31G and MP2/6-31+G levels of theory. For naphthalene and anthracene, the calculations yield two low energy dimers of very similar energies: D{sub 2d} (crossed) and C{sub 2h} (parallel-displaced). Conformers, analogous to the T-shaped dimer of benzene, are less stable than the crossed and the parallel-displaced dimers. BSSE-corrected MP2/6-31+G/MP2/6-31G binding energies of the crossed and the parallel-displaced dimers are, respectively, 15.77 and 15.65 kJ/mol for naphthalene and 36.40 and 31.84 kJ/mol for anthracene. The fully optimized MP2/6-31G structures of the parallel-displaced dimer of naphthalene has a horizontal displacement of 1.5 {angstrom} along the short axes of the monomers and a vertical displacement of 3.5 {angstrom}. The corresponding horizontal and vertical separations for the parallel-displaced (PD) dimer of anthracene are 1.1 and 3.6 {angstrom}, respectively. for the crossed dimers, the vertical separation of the aromatic rings is 3.6 {angstrom} for naphthalene and 3.3 {angstrom} for anthracene. The greater binding energy and the shorter horizontal displacement of the anthracene PD dimer relative to the naphthalene PD dimer are consistent with the stronger dispersion interactions expected of a larger dimer. The greater stability and smaller vertical separation of the crossed dimer of anthracene relative to that of naphthalene can also be attributed to the disparity in the dispersion interactions.

  19. Aus Wirtschaft und Betrieb. Biomasse: Gewinnung und Verarbeitung mit Profilschal-maschinen

    Treesearch

    P. Koch

    1977-01-01

    1963 wurden in den Südstaaten der USA nur 30% der oberund unterirdischen Biomasse der geernteten sog. Southern pines für Schnittholz und Zellstoff verwertet bzw. als getrockneies, gehobletes und abgelängtes Schnittholz oder als Kraftpapier verkauft. Keine der zusammen mit den Kiefern vorkommenden Laubholzarten wurde bisher in nennenswertem Umfan verwertet. Auch heute...

  20. A new potential energy surface for OH(A 2Sigma(+))-Ar: the van der Waals complex and scattering dynamics.

    PubMed

    Kłos, J; Alexander, M H; Brouard, M; Eyles, C J; Aoiz, F J

    2008-08-07

    New ab initio studies of the OH(A (2)Sigma(+))-Ar system reveal significantly deeper potential energy wells than previously believed, particularly for the linear configuration in which Ar is bound to the oxygen atom side of OH(A (2)Sigma(+)). In spite of this difference with previous ab initio work, bound state calculations based on a new RCCSD(T) potential energy surface yield an energy level structure in reasonable accord with previous theoretical and experimental studies. Preliminary open and closed shell quantum mechanical and quasiclassical trajectory scattering calculations are also performed on the new potential energy surface surface. The findings are discussed in the light of previous theoretical and experimental results for rotational energy transfer in collisions of OH(A (2)Sigma(+)) with Ar.

  1. Investigations of the Rg-BrCl (Rg=He, Ne, Ar, Kr, Xe) binary van der Waals complexes: ab initio intermolecular potential energy surfaces, vibrational states and predicted pure rotational transition frequencies.

    PubMed

    Li, Song; Zheng, Rui; Chen, Shan-Jun; Chen, Yan; Chen, Peng

    2017-03-05

    The intermolecular potential energy surfaces (PESs) of the ground electronic state for the Rg-BrCl (Rg=He, Ne, Ar, Kr, Xe) van der Waals complexes have been constructed by using the coupled-cluster method in combination with the augmented quadruple-zeta correlation-consistent basis sets supplemented with an additional set of bond functions. The features of the anisotropic PESs for these complexes are remarkably similar, which are characterized by three minima and two saddle points between them. The global minimum corresponds to a collinear Rg-Br-Cl configuration. Two local minima, correlate with an anti-linear Rg-Cl-Br geometry and a nearly T-shaped structure, can also be located on each PES. The quantum bound state calculations enable us to investigate intermolecular vibrational states and rotational energy levels of the complexes. The transition frequencies are predicted and are fitted to obtain their corresponding spectroscopic constants. In general, the periodic trends are observed for this complex family. Comparisons with available experimental data for the collinear isomer of Ar-BrCl demonstrate reliability of our theoretical predictions, and our results for the other two isomers of Ar-BrCl as well as for other members of the complex family are also anticipated to be trustable. Except for the collinear isomer of Ar-BrCl, the data presented in this paper would be beneficial to improve our knowledge for these experimentally unknown species.

  2. Layer specific optical band gap measurement at nanoscale in MoS{sub 2} and ReS{sub 2} van der Waals compounds by high resolution electron energy loss spectroscopy

    SciTech Connect

    Dileep, K. E-mail: ranjan@jncasr.ac.in; Sahu, R.; Datta, R. E-mail: ranjan@jncasr.ac.in; Sarkar, Sumanta; Peter, Sebastian C.

    2016-03-21

    Layer specific direct measurement of optical band gaps of two important van der Waals compounds, MoS{sub 2} and ReS{sub 2}, is performed at nanoscale by high resolution electron energy loss spectroscopy. For monolayer MoS{sub 2}, the twin excitons (1.8 and 1.95 eV) originating at the K point of the Brillouin zone are observed. An indirect band gap of 1.27 eV is obtained from the multilayer regions. Indirect to direct band gap crossover is observed which is consistent with the previously reported strong photoluminescence from the monolayer MoS{sub 2}. For ReS{sub 2}, the band gap is direct, and a value of 1.52 and 1.42 eV is obtained for the monolayer and multilayer, respectively. The energy loss function is dominated by features due to high density of states at both the valence and conduction band edges, and the difference in analyzing band gap with respect to ZnO is highlighted. Crystalline 1T ReS{sub 2} forms two dimensional chains like superstructure due to the clustering between four Re atoms. The results demonstrate the power of HREELS technique as a nanoscale optical absorption spectroscopy tool.

  3. Investigations of the Rg-BrCl (Rg = He, Ne, Ar, Kr, Xe) binary van der Waals complexes: ab initio intermolecular potential energy surfaces, vibrational states and predicted pure rotational transition frequencies

    NASA Astrophysics Data System (ADS)

    Li, Song; Zheng, Rui; Chen, Shan-Jun; Chen, Yan; Chen, Peng

    2017-03-01

    The intermolecular potential energy surfaces (PESs) of the ground electronic state for the Rg-BrCl (Rg = He, Ne, Ar, Kr, Xe) van der Waals complexes have been constructed by using the coupled-cluster method in combination with the augmented quadruple-zeta correlation-consistent basis sets supplemented with an additional set of bond functions. The features of the anisotropic PESs for these complexes are remarkably similar, which are characterized by three minima and two saddle points between them. The global minimum corresponds to a collinear Rg-Br-Cl configuration. Two local minima, correlate with an anti-linear Rg-Cl-Br geometry and a nearly T-shaped structure, can also be located on each PES. The quantum bound state calculations enable us to investigate intermolecular vibrational states and rotational energy levels of the complexes. The transition frequencies are predicted and are fitted to obtain their corresponding spectroscopic constants. In general, the periodic trends are observed for this complex family. Comparisons with available experimental data for the collinear isomer of Ar-BrCl demonstrate reliability of our theoretical predictions, and our results for the other two isomers of Ar-BrCl as well as for other members of the complex family are also anticipated to be trustable. Except for the collinear isomer of Ar-BrCl, the data presented in this paper would be beneficial to improve our knowledge for these experimentally unknown species.

  4. The Yeast Plasma Membrane ATP Binding Cassette (ABC) Transporter Aus1

    PubMed Central

    Marek, Magdalena; Milles, Sigrid; Schreiber, Gabriele; Daleke, David L.; Dittmar, Gunnar; Herrmann, Andreas; Müller, Peter; Pomorski, Thomas Günther

    2011-01-01

    The ATP binding cassette (ABC) transporter Aus1 is expressed under anaerobic growth conditions at the plasma membrane of the yeast Saccharomyces cerevisiae and is required for sterol uptake. These observations suggest that Aus1 promotes the translocation of sterols across membranes, but the precise transport mechanism has yet to be identified. In this study, an extraction and purification procedure was developed to characterize the Aus1 transporter. The detergent-solubilized protein was able to bind and hydrolyze ATP. Mutagenesis of the conserved lysine to methionine in the Walker A motif abolished ATP hydrolysis. Likewise, ATP hydrolysis was inhibited by classical inhibitors of ABC transporters. Upon reconstitution into proteoliposomes, the ATPase activity of Aus1 was specifically stimulated by phosphatidylserine (PS) in a stereoselective manner. We also found that Aus1-dependent sterol uptake, but not Aus1 expression and trafficking to the plasma membrane, was affected by changes in cellular PS levels. These results suggest a direct interaction between Aus1 and PS that is critical for the activity of the transporter. PMID:21521689

  5. Grundlagen der Organisationsgestaltung

    NASA Astrophysics Data System (ADS)

    Spath, Dieter; Koch, Steffen

    In diesem Kapitel werden Grundlagen der Organisationsgestaltung dargestellt. Es scheint nahe liegend, diese Inhalte wie in einem Lehrbuch aufzubereiten. Schließlich handelt es sich um grundlegende Inhalte. Die Neufassung dieses Abschnitts ist aber stärker für Verantwortliche in Unternehmen geschrieben und weniger wissenschaftlich geprägt. Das "Lehrbuchwissen“ wird daher bewusst knapp gehalten. Das betrifft z.B. die Klärung des Organisationsbegriffes und die Fragen nach den Zielsetzungen und den Gestaltungsbereichen von Organisation. Stattdessen widmet sich das Kapitel ausführlicher den Fragen, ob es Trends in der Organisationsgestaltung gibt, welche wichtigen Einflussgrößen existieren und welche übergeordneten und beständigen Leitlinien es gibt.

  6. Direct Calculation of Short Circuit Reactance, Winding Strength, and Inherent Forms of Output Transformers (Direkte Berechung der Kurzschlussreaktanzen, Wicklungskraefte und Eigenformen von Leistungstransformatoren)

    DTIC Science & Technology

    2001-01-01

    erst dann treffen , wenn zum Vergleich Messwerte herangezogen werden. Wie ebenfalls im Abschnitt 3.2.2 beschrieben, fiihren die zusdtzlichen Schenkel...bleibt, ob der linke oder rechte Teil nach oben verlagert werden soil. Schlie3- lich kann man diese Auswahl bei jedler Wicklung unabhdngig treffen . Aus...Rechenzeit: Eine eindeutige Aussage, weiche Methode die schnellere ist, 1hsst sich nicht treffen . Emn einfaches Beispiel soil dieses belegen. Betrachtet wird

  7. Infrarot-Thermografie in der Instandhaltung der chemischen Industrie

    NASA Astrophysics Data System (ADS)

    Huber, Christian

    Als Folge der raschen technologischen Entwicklung preisgünstiger, leistungsfähiger Thermografiekameras rückte diese für viele Anwendungen nutzbringend einzusetzende Inspektionsmethode zunehmend ins Interesse der Instandhalter aller Branchen. Die Infrarot(IR)-Thermografie wird damit als Schadensfrüherkennungsmethode integriert in das Repertoire bereits langjährig angewendeter Methoden wie der Schwingungsmesstechnik, Schmierstoffanalyse, Fehlerdiagnose an elektrotechnischen Komponenten sowie die gesamte Fülle zerstörungsfreier Untersuchungen im Werkstoffbereich.

  8. Das Smart Meter Gateway - Der kritische Erfolgsfaktor für die Digitalisierung der Energiewende

    NASA Astrophysics Data System (ADS)

    Abs, Paul-Vincent

    Der kritische Erfolgsfaktor der Digitalisierung in der Energiewirtschaft liegt im bevorstehenden hohen Investitionsvolumen und der Beherrschung der neuen Technik. Ein Weg zur Kostenminimierung liegt im Zusammenschluss der einzelnen Akteure, um gemeinsame Skalenvorteile zu heben. Auch bieten neue Geschäftsmodelle die Möglichkeit, zusätzliche Erlöse zu generieren.

  9. Zero-energy modes and valley asymmetry in the Hofstadter spectrum of bilayer graphene van der Waals heterostructures with hBN

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Wallbank, J. R.; Mucha-Kruczyński, M.; McCann, E.; Fal'ko, V. I.

    2016-07-01

    We investigate the magnetic minibands of a heterostructure consisting of bilayer graphene (BLG) and hexagonal boron nitride (hBN) by numerically diagonalizing a two-band Hamiltonian that describes electrons in BLG in the presence of a moiré potential. Due to inversion-symmetry breaking characteristic for the moiré potential, the valley symmetry of the spectrum is broken, but despite this, the zero-energy Landau level in BLG survives, albeit with reduced degeneracy. In addition, we derive effective models for the low-energy features in the magnetic minibands and demonstrate the appearance of secondary Dirac points in the valence band, which we confirm by numerical simulations. Then, we analyze how single-particle gaps in the fractal energy spectrum produce a sequence of incompressible states observable under a variation of carrier density and magnetic field.

  10. Practice Report / Bericht aus der Praxis: Tutor training for a peer-assisted interprofessional communication seminar: A work in progress.

    PubMed

    Hundertmark, Jan; Homberg, Angelika; Alvarez, Simone; Lauber, Heike; Berger, Sarah; Büscher, Christiane; Schultz, Jobst-Hendrik; Mahler, Cornelia

    2017-05-01

    A novel peer-led communication seminar for medical students and for students of the Interprofessional Health Care B.Sc. degree programme at the Medical Faculty of Heidelberg is currently being developed to address the increasing need for interprofessional collaborative competencies in health care professionals. The core elements of this course include role plays in interprofessional communication situations, patient-centred professional practice, and reflections on underlying attitudes. Each seminar will be conducted by a team of two senior students from both undergraduate programmes, practising their new roles as interprofessional tutors and, at the same time, serving as competent role models for interprofessional collaboration. To provide tutors with the necessary didactic preparation, an interprofessional tutor training was developed and implemented. It was positively evaluated and well accepted by participants. The seminar and tutor training concept presented in this paper aims to foster (inter-)professional ethics and communication competency development in medical students. Copyright © 2017. Published by Elsevier GmbH.

  11. Direkte Kontakte zu Deutschland aus und in der Ferne (Direct Contact with Germany from and at a Distance).

    ERIC Educational Resources Information Center

    Wicke, Rainer E.

    This guide is a summary of ideas for enhancing the teaching of German through direct contact with Germany or German people without traveling abroad. The following ideas are highlighted: (1) correspondence (pen pals) with students in Germany; (2) audiotape recordings as an alternative to letter writing; (3) the exchange of videotape recordings with…

  12. van der Waals torque

    NASA Astrophysics Data System (ADS)

    Esquivel-Sirvent, Raul; Schatz, George

    2014-03-01

    The theory of generalized van der Waals forces by Lifshtz when applied to optically anisotropic media predicts the existence of a torque. In this work we present a theoretical calculation of the van der Waals torque for two systems. First we consider two isotropic parallel plates where the anisotropy is induced using an external magnetic field. The anisotropy will in turn induce a torque. As a case study we consider III-IV semiconductors such as InSb that can support magneto plasmons. The calculations of the torque are done in the Voigt configuration, that occurs when the magnetic field is parallel to the surface of the slabs. The change in the dielectric function as the magnetic field increases has the effect of decreasing the van der Waals force and increasing the torque. Thus, the external magnetic field is used to tune both the force and torque. The second example we present is the use of the torque in the non retarded regime to align arrays of nano particle slabs. The torque is calculated within Barash and Ginzburg formalism in the nonretarded limit, and is quantified by the introduction of a Hamaker torque constant. Calculations are conducted between anisotropic slabs of materials including BaTiO3 and arrays of Ag nano particles. Depending on the shape and arrangement of the Ag nano particles the effective dielectric function of the array can be tuned as to make it more or less anisotropic. We show how this torque can be used in self assembly of arrays of nano particles. ref. R. Esquivel-Sirvent, G. C. Schatz, Phys. Chem C, 117, 5492 (2013). partial support from DGAPA-UNAM.

  13. Nonadiabatic corrections to the van der Waals potential

    NASA Technical Reports Server (NTRS)

    Au, C. K.

    1988-01-01

    Closed-form expressions are derived for the finite-mass nonadiabatic corrections to the van der Waals potential in the electric-dipole approximations in terms of London-analog two-center atomic spectral sums. The nonadiabatic corrections to all orders at threshold energy and also those with first-order energy dependence are given.

  14. Validation of the Australian Propensity for Angry Driving Scale (Aus-PADS).

    PubMed

    Leal, Nerida L; Pachana, Nancy A

    2009-09-01

    The present study used a university sample to assess the test-retest reliability and validity of the Australian Propensity for Angry Driving Scale (Aus-PADS). The scale has stability over time, and convergent validity was established, as Aus-PADS scores correlated significantly with established anger and impulsivity measures. Discriminant validity was also established, as Aus-PADS scores did not correlate with Venturesomeness scores. The Aus-PADS has demonstrated criterion validity, as scores were correlated with behavioural measures, such as yelling at other drivers, gesturing at other drivers, and feeling angry but not doing anything. Aus-PADS scores reliably predicted the frequency of these behaviours over and above other study variables. No significant relationship between aggressive driving and crash involvement was observed. It was concluded that the Aus-PADS is a reliable and valid tool appropriate for use in Australian research, and that the potential relationship between aggressive driving and crash involvement warrants further investigation with a more representative (and diverse) driver sample.

  15. Zeit im Wandel der Zeit.

    NASA Astrophysics Data System (ADS)

    Aichelburg, P. C.

    Contents: Einleitung(P. C. Aichelburg). 1. Über Zeit, Bewegung und Veränderung (Aristoteles). 2. Ewigkeit und Zeit (Plotin). 3. Was ist die Zeit? (Augustinus). 4. Von der Zeit (Immanuel Kant). 5. Newtons Ansichten über Zeit, Raum und Bewegung (Ernst Mach). 6. Über die mechanische Erklärung irreversibler Vorgänge (Ludwig Boltzmann). 7. Das Maß der Zeit (Henri Poincaré). 8. Dauer und Intuition (Henri Bergson). 9. Die Geschichte des Unendlichkeitsproblems (Bertrand Russell). 10. Raum und Zeit (Hermann Minkowski). 11. Der Unterschied von Zeit und Raum (Hans Reichenbach). 12. Newtonscher und Bergsonscher Zeitbegriff (Norbert Wiener). 13. Die Bildung des Zeitbegriffs beim Kinde (JeanPiaget).14. Eine Bemerkung über die Beziehungen zwischen Relativitätstheorie und der idealistischen Philosophie (Kurt Gödel). 15. Der zweite Hauptsatz und der Unterschied von Vergangenheit und Zukunft (Carl Friedrich v. Weizsäcker). 16. Zeit als physikalischer Begriff (Friedrich Hund). 17. Zeitmessung und Zeitbegriff in der Astronomie (Otto Heckmann). 18. Kann die Zeit rückwärts gehen? (Martin Gardner). 19. Zeit und Zeiten (Ilya Prigogine, Isabelle Stengers). 20. Zeit als dynamische Größe in der Relativitätstheorie (P. C. Aichelburg).

  16. Leistungsmessungen zum Einsatz der J2EE Technologie für Feldbussimulationen

    NASA Astrophysics Data System (ADS)

    Garreis, Thorsten; Jürgens, Hendrik; Schmidtmann, Uwe; von Cölin, Gerd

    Die Flexibilisierung der Fertigung und kurze Produktzyklen setzen einen beschleunigten, möglichst fehlerfreien Entwicklungsprozess voraus. Dieses Ziel kann jedoch nur erreicht werden, wenn bereits parallel zur Hardwareentwicklung die Software mit Hilfe einer Simulation der Hardware entwickelt und getestet werden kann. Darüber hinaus können mit Simulationen alternative Lösungen studiert werden, die zu optimierten Verfahren führen. In dieser Arbeit werden Leistungstests an der Simulationsumgebung drd-Simulator präsentiert, die auf der J2EE-Technologie1 basiert. Für die Messungen wird eine Soft-SPS eingesetzt, deren Feldbus vom Typ ModbusTCP simuliert wird. Erste Messungen zeigen, dass J2EE eine leistungsstarke und skalierbare Plattform für die Realisierung von Feldbussimulationen ist. In einem Zyklusbereich ab 100 ms ist das E/A-Verhalten echtzeitfähig, wobei meherere Steuerungen auf den Bus zugreifen können. Die J2EE-Technologie zeichnet sich zudem durch eine gute Ausfallsicherheit und dynamische Rekonfigurier-barkeit aus, so dass Tests dynamisch zur Laufzeit ergänzt oder verändert werden können.

  17. Physik-Nobelpreis 2004 Von der Freiheit in der Welt der Quarks

    NASA Astrophysics Data System (ADS)

    Bartels, Jochen

    2004-11-01

    Die Schwedische Akademie der Wissenschaften vergab in diesem Jahr den Physik-Nobelpreis zu gleichen Teilen an die amerikanischen Physiker David Gross, David Politzer und Frank Wilczek. Sie würdigte damit ihre theoretischen Arbeiten zur asymptotischen Freiheit in der starken Wechselwirkung.

  18. Verantwortlicher Umgang mit Antibiotika: Notwendigkeit der Antibiotikareduktion in der Aknetherapie.

    PubMed

    Gollnick, Harald P M; Buer, Jan; Beissert, Stefan; Sunderkätter, Cord

    2016-12-01

    Der übermäßige oder unkritische weltweite Einsatz von Antibiotika in der Medizin hat die Ausbreitung von Antibiotikaresistenzen beschleunigt. In einigen Bereichen sind viele Antibiotika bei bakteriellen Infektionen, die zuvor noch gut auf antibakterielle Wirkstoffe reagierten, mittlerweile wirkungslos geworden. Dermatologen/Venerologen setzten orale und topische Antibiotika bei der Behandlung von Acne vulgaris routinemäßig ein, obwohl Akne weder eine infektiöse Erkrankung ist noch alleine durch das Propionibacterium getriggert wird. Vielmehr ist sie eine komplexe, chronische entzündliche Hauterkrankung, die durch verschiedene pathogenetische Faktoren wie follikuläre Hyperkeratose, erhöhter Sebumproduktion, bakterielle Proliferation und Entzündung zustande kommt. Folglich sollte eine erfolgreiche Therapie auf die Bekämpfung verschiedener pathogenetischer Faktoren und nicht nur auf die von Propionibacterium acnes abzielen. Daher wurden topische Retinoide und Benzoylperoxid als Mittel der ersten Wahl definiert. Monotherapien mit lokalen Antibiotika sollten insgesamt vermieden werden. Systemische Antibiotika der Tetrazyklin-Gruppe haben bei bestimmen Krankheitsstadien ihren Sinn, ihre Wirkung könnte aber eher auf der antientzündlichen als auf der antibiotischen Reaktion beruhen. Gesundheitsbehörden ermahnen alle Gesundheitsdienstleister, den Einsatz von Antibiotika einzuschränken. Das Nutzen-Risiko-Verhältnis muss bei der Entscheidung für oder gegen eine antibiotische Therapie bei einem einzelnen Patienten immer auch in Bezug auf das öffentliche Interesse am Erhalt der Wirksamkeit von Antibiotika abgewogen werden. Im Folgenden werden das aktuelle Krankheitskonzept zu Acne vulgaris und die sich daraus ableitenden Konsequenzen für den Einsatz von Antibiotika vorgestellt. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  19. Grundlagen und Vollzug der amtlichen Lebensmittelkontrolle in der Schweiz

    NASA Astrophysics Data System (ADS)

    Hübner, Philipp; Spinner, Christoph

    In der Schweiz wird die Mehrheit der hoheitlichen Aufgaben von den 26 Kantonen, die zusammen die schweizerische Eidgenossenschaft bilden, autonom vollzogen. So liegt zum Beispiel die Kompetenz in den Bereichen Steuern, Gesundheit, Schulen oder Polizei grundsätzlich bei den Kantonen. Im Gegensatz dazu ist die Lebensmittelgesetzgebung national durch eidgenössische Erlasse harmonisiert. Die Vollzugsaufgaben liegen aber auch in diesem Bereich, abgesehen vom Vollzug an der Grenze und von einer nationalen Vollzugsaufsicht und Weisungsberechtigung, in kantonaler Kompetenz. Die Kantone können anhand kantonaler Erlasse das Bundesrecht präzisieren - insbesondere die organisatorischen Aspekte - und Regelungen im nicht harmonisierten Bereich treffen.

  20. Das Lob der Sternkunst. Astronomie in der deutschen Aufklärung.

    NASA Astrophysics Data System (ADS)

    Baasner, R.

    Contents: 1. Einleitung. 2. Die Astronomie im Rahmen der Aufklärungs-Physik. 3. Das Lob der Sternkunst. 4. Ein Blick auf die Sternwarten. 5. Allgemeine Darstellungen der Sternkunde. 6. Schleppende Rezeption: Das kopernikanische Weltbild. 7. Himmelsphysik: Die Debatte um die causa gravitatis. 8. Theorie der Himmelskörper. 9. Die Erde als Gegenstand der Astronomie. 10. Die Sonne. 11. Der Mond. 12. Die Planeten. 13. Die Kometen. 14. Die Fixsterne. 15. Die Entstehung der Welt. 16. Beiträge der Astrotheologie. 17. Der Kampf gegen die Astrologen.

  1. Die Baukastensystematik in der Fördertechnik

    NASA Astrophysics Data System (ADS)

    Sebulke, Johannes

    In der Fördertechnik wird kaum ein größerer Einsatzfall so dem anderen gleichen, dass man zwei Anlagen nach denselben Zeichnungen fertigen kann. Konstruktionszeiten, Rüst- und Umstellungszeiten der Fertigung sind hoch; der Kunde muss bei Einzelanfertigung lange Lieferzeiten in Kauf nehmen. In der Fördertechnik haben sich daher Baukastenprinzip, Standardisierung und die Konstruktion von Erzeugnisreihen weitgehend durchgesetzt.

  2. Verbesserung der Symmetrie von Hirnaufnahmen entlang der Sagittalebene

    NASA Astrophysics Data System (ADS)

    Ens, Konstantin; Wenzel, Fabian; Fischer, Bernd

    Die lokale Symmetrie von Hirnscans entlang der Sagittalebene zu ermitteln und zu modizifieren, ist für eine Reihe neurologischer Anwendungen interessant. Beispielsweise kann der voxelweise Vergleich von rechter und linker Hirnhälfte nur dann Aufschluss über die Lokalisierung von Läsionen geben, wenn durch Transformation ein Hirnscan eine möglichst hohe Symmetrie aufweist. Ein weiteres Anwendungsgebiet ist die Visualisierung von medialen Hirnschnitten, für die die Trennfläche beider Hirnhälfte möglichst eben sein sollte. Diese Arbeit stellt die Entwicklung eines Verfahrens vor, mit dessen Hilfe die Symmetrie von Hirnaufnahmen entlang der Sagittalebene verbessert werden kann. Dies geschieht unter Verwendung von aktiven Konturen, die mit Hilfe einer neuartigen Kostenfunktion gesteuert werden. Experimente am Ende der Arbeit mit strukturellen Kernspinaufnahmen demonstrieren die Leistungsfähigkeit des Verfahrens.

  3. Dialektischer Materialismus in der Quantentheorie

    NASA Astrophysics Data System (ADS)

    Fuchs, Klaus

    Der absolute Determinismus der klassischen Mechanik bietet keine Ansatzpunkte für eine befriedigende Naturphilosophie. Mit der Quantenmechanik werden nicht lediglich die Unzulänglichkeiten einzelner klassischer Begriffe, sondern die des gesamten klassischen Begriffssystems beseitigt.Translated AbstractDialectical Materialism in Quantum TheoryThe absolute determinism of classical mechanics does not provide any base for a satisfactory philosophy of nature. In quantum mechanics the shortcomings of not only some single classical concepts but of the classical description as a whole are removed.

  4. Review of Test Facilities for Distributed Energy Resources

    SciTech Connect

    AKHIL,ABBAS ALI; MARNAY,CHRIS; KIPMAN,TIMOTHY

    2003-05-01

    Since initiating research on integration of distributed energy resources (DER) in 1999, the Consortium for Electric Reliability Technology Solutions (CERTS) has been actively assessing and reviewing existing DER test facilities for possible demonstrations of advanced DER system integration concepts. This report is a compendium of information collected by the CERTS team on DER test facilities during this period.

  5. Online Condition Monitoring mit der Stresswellenanalyse

    NASA Astrophysics Data System (ADS)

    Bruderreck, Frank

    Die Anforderungen des heutigen Energiemarkts und damit einhergehende veränderte Einsatzbedingungen für ältere Kraftwerksblöcke haben unvorhergesehene Produktionsausfälle in den letzten Jahren erheblich verteuert. Nach der Optimierung der Kraftwerksprozesse und der Steigerung der Wirkungsgrade richten die Energieversorger ihren Blick daher nun verstärkt auch auf die Verfügbarkeit ihrer Anlagen. Zur Verbesserung der Anlagenverfügbarkeit und der Minimierung der Instandhaltungskosten bietet sich der Einsatz von Condition Monitoring Systemen an. Nach der Erprobung eines Systems zur Vibrationsanalyse setzt die Evonik Steag GmbH jetzt in einem Pilotprojekt die Stresswellenanalyse ein, ein Online Condition Monitoring System auf der Basis von Ultraschallsensoren. Dieser Beitrag erläutert an einem Beispiel die Methode und grenzt sie gegen den De-facto-Standard Vibrationsanalyse ab.

  6. Malignancy rate associated with Bethesda category III (AUS/FLUS) with and without repeat fine needle aspiration biopsy.

    PubMed

    Kuru, Bekir; Atmaca, Aysegul; Kefeli, Mehmet

    2016-05-01

    Selection of nodules for surgery diagnosed as Bethesda category III [atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) category] is important. It was aimed to define the malignancy rates associated with and without repeat fine needle aspiration biopsy (FNAB) and to define the contribution of repeat FNAB to triage to surgery or observation in nodules with AUS/FLUS FNAB. The records of all patients with nodules who underwent FNAB and classified by Bethesda reporting system as AUS/FLUS at their institution were reviewed. Malignancy rates for patients with AUS/FLUS FNAB with and without repeat FNAB were calculated. Of the 582 patients who were classified as AUS/FLUS on initial FNAB, 179 underwent surgery with an associated malignancy rate of 22.9% (upper boundary). Risk of malignancy among all patients with AUS/FLUS nodules was 7% (lower boundary). The upper and lower boundaries of the malignancy rates with and without repeat FNAB were 38.6% and 15.6% for resected patients, and 13% and 4.6% for all patients, respectively. Reclassification rate with repeat FNAB was 56%. The findings showed that repeat FNAB for initial AUS/FLUS category was associated with a significantly increased malignancy rate compared with those without repeat FNAB. Repeat FNAB could help selection of patients with AUS/FLUS to triage to surgery. Therefore, repeat FNAB for nodules with AUS/FLUS on initial FNAB was suggested. © 2016 Wiley Periodicals, Inc.

  7. Der evolutionäre Naturalismus in der Ethik

    NASA Astrophysics Data System (ADS)

    Kaiser, Marie I.

    Charles Darwin hat eindrucksvoll gezeigt, dass der Mensch ebenso wie alle anderen Lebewesen ein Produkt der biologischen Evolution ist. Die sich an Darwin anschließende Forschung hat außerdem plausibel gemacht, dass sich nicht nur viele der körperlichen Merkmale des Menschen, sondern auch (zumindest einige) seiner Verhaltensdispositionen in adaptiven Selektionsprozessen herausgebildet haben. Die Vorstellung, dass auch die menschliche Moralität evolutionär bedingt ist, scheint daher auf den ersten Blick ganz überzeugend. Schließlich hat die Evolutionstheorie in den vergangenen Jahrzehnten in vielen Bereichen (auch außerhalb der Biologie) ihre weitreichende Bedeutung unter Beweis gestellt. Warum sollte, so könnte man beispielsweise fragen, gerade die Fähigkeit des Menschen, moralische Normen aufzustellen und gemäß ihnen zu handeln, nicht evolutionär erklärt werden können? Und warum sollte eine solche evolutionäre Erklärung der menschlichen Moralität irrelevant für die Rechtfertigung moralischer Normen sein? Warum sollte die Ethik eine Bastion der Philosophen bleiben, für die evolutionsbiologische Forschungsergebnisse über den Menschen und seine nächsten Verwandten keinerlei Relevanz besitzen?

  8. Auf der Suche nach dem Unendlichen.

    NASA Astrophysics Data System (ADS)

    Fraser, G.; Lillestøl, E.; Sellevåg, I.

    This book is a German translation by C. Ascheron and J. Urbahn, of "The search for infinity: solving the mysteries of the universe", published in 1994. Diese Buch beschreibt anschaulich die Meilensteine, die der Mensch seit der Antike auf der Suche nach dem Unendlichen erreicht und hinter sich gelassen hat. Es enthält Kurzbiographien der wichtigsten Forscher, verständlich geschriebene Texte sowie Erläuterungen der entscheidenen Fachtermini.

  9. Van der Waals forces in pNRQED

    SciTech Connect

    Shtabovenko, Vladyslav

    2016-01-22

    We report on the calculation of electromagnetic van der Waals forces [1] between two hydrogen atoms using non-relativistic effective field theories (EFTs) of QED for large and small momentum transfers with respect to the intrinsic energy scale of the hydrogen atom. Our results reproduce the well known London and Casimir-Polder forces.

  10. Applying DER-CAM for IIT Microgrid Explansion Planning

    SciTech Connect

    Shahidehpour, Mohammad; Li, Zuyi; Wang, Jianhui; Chen, Chen

    2016-04-19

    The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an economic and environmental model of customer DER adoption. This model has been in development at the Lawrence Berkeley National Laboratory since 2000. The objective of the model is to find optimal DER investments while minimizing total energy costs or carbon dioxide (CO2) emissions, or achieving a weighted objective that simultaneously considers both criteria. The Illinois Institute of Technology (IIT) Microgrid project started in August 2008, and the majority of the project was completed in May 2013. IIT Microgrid, funded mostly by a grant from the U.S. Department of Energy as well as State and philanthropic contributions, empowers the campus consumers with the objective of establishing a smart microgrid that is highly reliable, economically viable, environmentally friendly, fuel-efficient, and resilient in extreme circumstances with a self-healing capability. In this project, we apply DER-CAM to study the expansion planning of the IIT Microgrid. First, the load data, environmental data, utility data, and technology data for the IIT Microgrid are gathered and organized to follow the DER-CAM input requirements. Then, DERCAM is applied to study the expansion planning of the IIT Microgrid for different cases, where different objectives in DER-CAM and different utility conditions are tested. Case 1 considers the objective of minimizing energy costs with fixed utility rates and 100% electric utility availability. Case 2 considers the objective of minimizing energy costs with real-time utility rates and 4 emergency weeks when the IIT Microgrid does not have access to the electric utility grid and has to operate in island mode. In Case 3, the utility rates are restored to fixed values and 100% electric utility availability is assumed, but a weighted multi-objective (Obj: a × costs + b × CO2 emissions, where a and b are weights for cost minimization and CO2 emissions minimization) is utilized to

  11. Cold Anisotropically Interacting van der Waals Molecule: TiHe.

    PubMed

    Quiros, Nancy; Tariq, Naima; Tscherbul, Timur V; Kłos, Jacek; Weinstein, Jonathan D

    2017-05-26

    We have used laser ablation and helium buffer-gas cooling to produce titanium-helium van der Waals molecules at cryogenic temperatures. The molecules were detected through laser-induced fluorescence spectroscopy. Ground-state Ti(a^{3}F_{2})-He binding energies were determined for the ground and first rotationally excited states from studying equilibrium thermodynamic properties, and found to agree well with theoretical calculations based on newly calculated ab initio Ti-He interaction potentials, opening up novel possibilities for studying the formation, dynamics, and nonuniversal chemistry of van der Waals clusters at low temperatures.

  12. Cold Anisotropically Interacting van der Waals Molecule: TiHe

    NASA Astrophysics Data System (ADS)

    Quiros, Nancy; Tariq, Naima; Tscherbul, Timur V.; Kłos, Jacek; Weinstein, Jonathan D.

    2017-05-01

    We have used laser ablation and helium buffer-gas cooling to produce titanium-helium van der Waals molecules at cryogenic temperatures. The molecules were detected through laser-induced fluorescence spectroscopy. Ground-state Ti (a 3F2)-He binding energies were determined for the ground and first rotationally excited states from studying equilibrium thermodynamic properties, and found to agree well with theoretical calculations based on newly calculated ab initio Ti-He interaction potentials, opening up novel possibilities for studying the formation, dynamics, and nonuniversal chemistry of van der Waals clusters at low temperatures.

  13. Materials perspective on Casimir and van der Waals interactions

    NASA Astrophysics Data System (ADS)

    Woods, L. M.; Dalvit, D. A. R.; Tkatchenko, A.; Rodriguez-Lopez, P.; Rodriguez, A. W.; Podgornik, R.

    2016-10-01

    Interactions induced by electromagnetic fluctuations, such as van der Waals and Casimir forces, are of universal nature present at any length scale between any types of systems. Such interactions are important not only for the fundamental science of materials behavior, but also for the design and improvement of micro- and nanostructured devices. In the past decade, many new materials have become available, which has stimulated the need for understanding their dispersive interactions. The field of van der Waals and Casimir forces has experienced an impetus in terms of developing novel theoretical and computational methods to provide new insights into related phenomena. The understanding of such forces has far reaching consequences as it bridges concepts in materials, atomic and molecular physics, condensed-matter physics, high-energy physics, chemistry, and biology. This review summarizes major breakthroughs and emphasizes the common origin of van der Waals and Casimir interactions. Progress related to novel ab initio modeling approaches and their application in various systems, interactions in materials with Dirac-like spectra, force manipulations through nontrivial boundary conditions, and applications of van der Waals forces in organic and biological matter are examined. The outlook of the review is to give the scientific community a materials perspective of van der Waals and Casimir phenomena and stimulate the development of experimental techniques and applications.

  14. Materials perspective on Casimir and van der Waals interactions

    SciTech Connect

    Woods, L. M.; Dalvit, D. A. R.; Tkatchenko, A.; Rodriguez-Lopez, P.; Rodriguez, A. W.; Podgornik, R.

    2016-11-02

    Interactions induced by electromagnetic fluctuations, such as van der Waals and Casimir forces, are of universal nature present at any length scale between any types of systems. In such interactions these are important not only for the fundamental science of materials behavior, but also for the design and improvement of micro- and nanostructured devices. In the past decade, many new materials have become available, which has stimulated the need for understanding their dispersive interactions. The field of van der Waals and Casimir forces has experienced an impetus in terms of developing novel theoretical and computational methods to provide new insights into related phenomena. The understanding of such forces has far reaching consequences as it bridges concepts in materials, atomic and molecular physics, condensed-matter physics, high-energy physics, chemistry, and biology. Our review summarizes major breakthroughs and emphasizes the common origin of van der Waals and Casimir interactions. Progress related to novel ab initio modeling approaches and their application in various systems, interactions in materials with Dirac-like spectra, force manipulations through nontrivial boundary conditions, and applications of van der Waals forces in organic and biological matter are examined. Finally, the outlook of the review is to give the scientific community a materials perspective of van der Waals and Casimir phenomena and stimulate the development of experimental techniques and applications.

  15. Van der Waals interaction in uniaxial anisotropic media.

    PubMed

    Kornilovitch, Pavel E

    2013-01-23

    Van der Waals interactions between flat surfaces in uniaxial anisotropic media are investigated in the nonretarded limit. The main focus is the effect of nonzero tilt between the optical axis and the surface normal on the strength of the van der Waals attraction. General expressions for the van der Waals free energy are derived using the surface mode method and the transfer-matrix formalism. To facilitate numerical calculations a temperature-dependent three-band parameterization of the dielectric tensor of the liquid crystal 5CB is developed. A solid slab immersed in a liquid crystal experiences a van der Waals torque that aligns the surface normal relative to the optical axis of the medium. The preferred orientation is different for different materials. Two solid slabs in close proximity experience a van der Waals attraction that is strongest for homeotropic alignment of the intervening liquid crystal for all the materials studied. The results have implications for the stability of plate-like colloids in liquid crystal hosts.

  16. Materials perspective on Casimir and van der Waals interactions

    DOE PAGES

    Woods, L. M.; Dalvit, D. A. R.; Tkatchenko, A.; ...

    2016-11-02

    Interactions induced by electromagnetic fluctuations, such as van der Waals and Casimir forces, are of universal nature present at any length scale between any types of systems. In such interactions these are important not only for the fundamental science of materials behavior, but also for the design and improvement of micro- and nanostructured devices. In the past decade, many new materials have become available, which has stimulated the need for understanding their dispersive interactions. The field of van der Waals and Casimir forces has experienced an impetus in terms of developing novel theoretical and computational methods to provide new insightsmore » into related phenomena. The understanding of such forces has far reaching consequences as it bridges concepts in materials, atomic and molecular physics, condensed-matter physics, high-energy physics, chemistry, and biology. Our review summarizes major breakthroughs and emphasizes the common origin of van der Waals and Casimir interactions. Progress related to novel ab initio modeling approaches and their application in various systems, interactions in materials with Dirac-like spectra, force manipulations through nontrivial boundary conditions, and applications of van der Waals forces in organic and biological matter are examined. Finally, the outlook of the review is to give the scientific community a materials perspective of van der Waals and Casimir phenomena and stimulate the development of experimental techniques and applications.« less

  17. Der Organismus der Mathematik - mikro-, makro- und mesoskopisch betrachtet

    NASA Astrophysics Data System (ADS)

    Winkler, Reinhard

    Meist enden ähnliche Gespräche über Mathematik etwa an diesem Punkt, ohne dass der Nichtmathematiker von der Sinnhaftigkeit mathematischer Forschung, ja mathematischer Tätigkeit generell überzeugt werden konnte. Ich glaube nicht, dass dem Laien Blindheit für die Großartigkeit unserer Wissenschaft vorzuwerfen ist, wenn hier keine befriedigendere Kommunikation zustande kommt. Ich sehe als Ursache eher ein stark verkürztes Bild von der Mathematik, welches auch Fachleute oft zeichnen, weil ihnen eine angemessenere Darstellung ihres Faches zu viel Mühe macht - und das obwohl Mathematik nur betreiben kann, wer geistige Mühen sonst keineswegs scheut. Ich will versuchen, den Ursachen dieses eigentümlichen Phänomens auf den Grund zu gehen.

  18. Optimierung von FSS-Bandpassfiltern mit Hilfe der Schwarmintelligenz (Particle Swarm Optimization)

    NASA Astrophysics Data System (ADS)

    Wu, G.; Hansen, V.; Kreysa, E.; Gemünd, H.-P.

    2006-09-01

    In diesem Beitrag wird ein neues Verfahren zur Optimierung von Bandpassfiltern aus mehrlagigen frequenzselektiven Schirmen (FSS), die in ein Dielektrikum eingebettet sind, vorgestellt. Das Ziel ist es, die Parameter der gesamten Struktur so zu optimieren, dass ihre Transmissionseigenschaften hohe Filteranforderungen erfüllen. Als Optimierungsverfahren wird die Particle Swarm Optimization (PSO) eingesetzt. PSO ist eine neue stochastische Optimierungsmethode, die in verschieden Gebieten, besonders aber bei der Optimierung nicht linearer Probleme mit mehreren Zielfunktionen erfolgreich eingesetzt wird. In dieser Arbeit wird die PSO in die Spektralbereichsanalyse zur Berechnung komplexer FSS-Strukturen integriert. Die numerische Berechnung basiert auf einer Integralgleichungsformulierung mit Hilfe der spektralen Greenschen Funktion für geschichtete Strukturen. This paper presents a novel procedure for the optimization of band-pass filters consisting of frequency selective surfaces (FSS) embedded in a dielectric. The aim is to optimize the parameters of the complete structure so that the transmission characteristics of the filters fulfill the demanding requirements. The Particle Swarm Optimization (PSO) is used as the optimization procedure. PSO is a new stochastic optimization method that is successfully applied in different areas for the optimization of non-linear problems with several object-functions. In this work, PSO is integrated into the spectral domain analysis for the calculation of the complex FSS structures. The numerical computation is based on the formulation of an integral equation with the help of the spectral Green's function for layered media.

  19. Anwendungsgebiete und Nutzen der RFID-Technologie in der Instandhaltung

    NASA Astrophysics Data System (ADS)

    Müller, Gerhard; Plate, Cathrin

    Im Vergleich zu Fertigungsbereichen, in denen eine Vielzahl von Terminals den Zugriff auf Fertigungsinformationen und Produktionsdaten ermöglichen, sind viele Instandhaltungsbereiche dadurch gekennzeichnet, dass der Zugriff auf Anlagendaten, Planungs- und operative Informationen nur an wenigen Stationen des Instandhaltungsplanungs- und Steuerungssystems (IPS-System) vollzogen werden kann. Das IPS-System-Spektrum reicht von einfachen MS-Office Produkten über Stand-Alone-Applikationen der Instandhaltung (z. B. IPS-Systeme wie ApiPro oder WartMan) bis hin zu in Warenwirtschaftssysteme integrierten Instandhaltungsmodulen (z. B. SAP-PM).

  20. Review: Alternative Placement of Penile Prosthesis Reservoir and AUS Pressure Regulating Balloon.

    PubMed

    Reznicek, Daniel G; Bryson, Richard; Kramer, Andrew C

    2015-03-01

    Ectopic placement of prosthetic balloons and reservoirs in urological surgery has gained popularity, and early experience suggests that such placement is safe and efficacious. We review the artificial urinary sphincter (AUS) pressure regulating balloon (PRB) and inflatable penile prosthesis (IPP) reservoir placement and the factors relating to ectopic vs. traditional paravesical placement of these devices. Articles from peer-reviewed journals, abstracts, and surgeons' series of outcomes form the basis for this review. Relevant mechanical function of devices and pertinent anatomy is reviewed. To review the current data regarding ectopic and conventional reservoir placement for the AUS and IPP. Traditional and ectopic placements of the AUS PRB and IPP reservoir have been shown to be safe and effective. There are well-documented risks associated with both traditional and ectopic approaches, and these risks must be weighed in the context of a specific clinical scenario and surgeon comfort. Traditional and ectopic placement of prosthetic balloons and reservoirs should be guided by patient characteristics and surgeon experience. Our early experience is in agreement with that of others in that ectopic placement of these devices appears to be a viable alternative in the appropriately selected patient and may be a technically easy procedure to learn for the experienced prosthetic surgeon. Reznicek DG, Bryson R, and Kramer AC. Alternative placement of penile prosthesis reservoir and AUS pressure regulating balloon. Sex Med Rev 2015;3:48-55. Copyright © 2015 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

  1. Structure and dynamics of small van der Waals complexes

    SciTech Connect

    Loreau, J.

    2014-10-06

    We illustrate computational aspects of the calculation of the potential energy surfaces of small (up to five atoms) van der Waals complexes with high-level quantum chemistry techniques such as the CCSD(T) method with extended basis sets. We discuss the compromise between the required accuracy and the computational time. Further, we show how these potential energy surfaces can be fitted and used in dynamical calculations such as non-reactive inelastic scattering.

  2. Twisted Van der Waals Systems

    NASA Astrophysics Data System (ADS)

    Gani, Satrio; Rossi, Enrico

    Van der Waals systems formed by two-dimensional (2D) crystals and nanostructures possess electronic properties that make them extremely interesting for basic science and for possible technological applications. By tuning the relative angle (the twist angle) between the layers, or nanostructures, forming the Van der Waals systems experimentalists have been able to control the stacking configuration of such systems. We study the dependence on the twist angle of the electronic properties of two classes of Van der Waals systems: double layers formed by two, one-atom thick, layers of a metal dichalcogenide such as molybdenum disulfide (MoS2), and graphene nanoribbons on a hexagonal boron nitride substrate. We present results that show how, for both classes of systems, the electronic properties can be strongly tuned via the twist angle. Work supported by ACS-PRF-53581-DNI5 and NSF-DMR-1455233.

  3. Grundlagen und Grundbegriffe der Messtechnik

    NASA Astrophysics Data System (ADS)

    Plaßmann, Wilfried

    Es ist eine wesentliche Aufgabe der Messtechnik, technische Vorgänge quantitativ zu erfassen und anhand der gemessenen Größen Funktionsabläufe zu steuern. Als Beispiel sei ein Kraftwerk zur Energieerzeugung genannt, bei dem nur über die Messung von Temperaturen, Leistungen, Drücken und anderen Größen Aussagen über den momentanen Zustand möglich sind und bei Abweichungen vom Sollwert geeignete Eingriffe in das System erfolgen können. Damit eine eindeutige Kommunikation möglich wird, sind die in der Messtechnik verwendeten Begriffe, Messverfahren und Maßeinheiten in entsprechenden Normen oder Vorschriften festgelegt.

  4. van der Waals Heterostructures Grown by MBE

    NASA Astrophysics Data System (ADS)

    Hinkle, Christopher

    In this work, we demonstrate the high-quality MBE heterostructure growth of various layered 2D materials by van der Waals epitaxy (VDWE). The coupling of different types of van der Waals materials including transition metal dichalcogenide thin films (e.g., WSe2, WTe2, HfSe2) , insulating hexagonal boron nitride (h-BN), and topological insulators (e.g., Bi2Se3) allows for the fabrication of novel electronic devices that take advantage of unique quantum confinement and spin-based characteristics. The relaxed lattice-matching criteria of van der Waals epitaxy has allowed for high-quality heterostructure growth with atomically abrupt interfaces, allowing us to couple these materials based primarily on their band alignment and electronic properties. We will discuss the impact of sample preparation, surface reactivity, and lattice mismatch of various substrates (sapphire, graphene, TMDs, Bi2Se3) on the growth mode and quality of the films and will discuss our studies of substrate temperature and flux rates on the resultant growth and grain size. Structural and chemical characterization was conducted via reflection high energy electron diffraction (RHEED, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning tunneling microscopy/spectroscopy (STM/S), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Experimentally determined band alignments have been determined and compared with first-principles calculations allowing the design of novel low-power logic and magnetic memory devices. Initial results from the electrical characterization of these grown thin films and some simple devices will also be presented. These VDWE grown layered 2D materials show significant potential for fabricating novel heterostructures with tunable band alignments and magnetic properties for a variety of nanoelectronic and optoelectronic applications.

  5. Effective field theories for van der Waals interactions

    NASA Astrophysics Data System (ADS)

    Brambilla, Nora; Shtabovenko, Vladyslav; Tarrús Castellà, Jaume; Vairo, Antonio

    2017-06-01

    Van der Waals interactions between two neutral but polarizable systems at a separation R much larger than the typical size of the systems are at the core of a broad sweep of contemporary problems in settings ranging from atomic, molecular and condensed matter physics to strong interactions and gravity. In this paper, we reexamine the dispersive van der Waals interactions between two hydrogen atoms. The novelty of the analysis resides in the usage of nonrelativistic effective field theories of quantum electrodynamics. In this framework, the van der Waals potential acquires the meaning of a matching coefficient in an effective field theory, dubbed van der Waals effective field theory, suited to describe the low-energy dynamics of an atom pair. It may be computed systematically as a series in R times some typical atomic scale and in the fine-structure constant α . The van der Waals potential gets short-range contributions and radiative corrections, which we compute in dimensional regularization and renormalize here for the first time. Results are given in d space-time dimensions. One can distinguish among different regimes depending on the relative size between 1 /R and the typical atomic bound-state energy, which is of order m α2. Each regime is characterized by a specific hierarchy of scales and a corresponding tower of effective field theories. The short-distance regime is characterized by 1 /R ≫m α2 and the leading-order van der Waals potential is the London potential. We also compute next-to-next-to-next-to-leading-order corrections. In the long-distance regime we have 1 /R ≪m α2. In this regime, the van der Waals potential contains contact terms, which are parametrically larger than the Casimir-Polder potential that describes the potential at large distances. In the effective field theory, the Casimir-Polder potential counts as a next-to-next-to-next-to-leading-order effect. In the intermediate-distance regime, 1 /R ˜m α2, a significantly more complex

  6. Der Begriff der Verständlichkeit in der modernen Physik (1948).

    PubMed

    Feyerabend, Paul K

    2016-06-01

    This is a critical transcription of Paul Feyerabend's earliest extant essay "Der Begriff der Verständlichkeit in der modernen Physik" (1948) recovered from the European Forum Alpbach archives. In it, Feyerabend defends positivism as a progressive framework for scientific research in certain stages of scientific development. He argues that in physics visualizability (Anschaulichkeit) and intelligibility (Verständlichkeit) are time-conditioned concepts: what is deemed visualizable in the development of physical theories is relative to a specific historical context and changes over time. He concludes that from time to time the abandonment of visualizability is crucial for progress in physics, as it is conducive to major theory change, illustrating the point on the basis of advances in atomic theory. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Discrete structure of van der Waals domains in globular proteins.

    PubMed

    Berezovsky, Igor N

    2003-03-01

    Most globular proteins are divisible by domains, distinct substructures of the globule. The notion of hierarchy of the domains was introduced earlier via van der Waals energy profiles that allow one to subdivide the proteins into domains (subdomains). The question remains open as to what is the possible structural connection of the energy profiles. The recent discovery of the loop-n-lock elements in the globular proteins suggests such a structural connection. A direct comparison of the segmentation by van der Waals energy criteria with the maps of the locked loops of nearly standard size reveals a striking correlation: domains in general appear to consist of one to several such loops. In addition, it was demonstrated that a variety of subdivisions of the same protein into domains is just a regrouping of the loop-n-lock elements.

  8. Segmentierung der Papille in Fundusaufnahmen Aktives Kreisbogen-Modell

    NASA Astrophysics Data System (ADS)

    Schmidt, Torsten; Doering, Axel

    In der vorliegenden Arbeit präsentieren wir einen praxistauglichen Algorithmus zur automatischen Segmentierung der Disc-Grenze der Papille in Fundusaufnahmen. Ausgehend von einem lokalisierten Papillenpunkt werden Grauwertverläufe in horizontaler und vertikaler Richtung mittels einer Energiefunktion ausgewertet. In einem iterativen Prozess wird die Ellipse der tatsächlichen Disc-Grenze angenähert. Der Papillenrand konnte im Testdatensatz in 88% der Aufnahmen erfolgreich segmentiert werden. Der Algorithmus ist robust gegenüber der Lage des Startpunktes innerhalb der Papille und soll als Unterstützung bei der Glaukombefundung eingesetzt werden.

  9. Die Bedeutung der blauen Farbe in der Dermatoskopie.

    PubMed

    Popadić, Mirjana; Sinz, Christoph; Kittler, Harald

    2017-03-01

    Hautläsionen mit blauer Färbung werden häufig chirurgisch entfernt, um Malignität auszuschließen zu können. Das Ziel der vorliegenden Studie war es, die Bedeutung der blauen Färbung zu untersuchen. Wir untersuchten dermatoskopische Bilder retrospektiv auf blaue Farbe und klassifizierten sie gemäß der Musteranalyse. Von 1.123 pigmentierten Hautläsionen wiesen 144 (12,8 %) eine blaue Färbung auf. Von diesen waren 92 (63,9 %) bösartig. Unter den Läsionen mit Blaufärbung waren Nävi (n = 35, 24,3 %) und seborrhoische Keratosen (n = 8, 5,6 %) die häufigsten gutartigen Diagnosen. Von 103 (71,5 %) Läsionen mit einem strukturlosen blauen Muster waren acht (7,8 %) vollständig blau gefärbt und 95 (92,2 %) teilweise blau, davon zeigten 81 (78,6 %) periphere oder fleckige und 14 (13.6 %) eine zentrale Blaufärbung. Die meisten Läsionen mit peripherer oder fleckiger blauer Färbung waren Melanome (n = 47, 58 %), wohingegen die meisten Läsionen mit zentraler Blaufärbung Nävi darstellten (n = 9, 64,3 %). Von 28 Läsionen mit blauen Schollen waren 17 (60,7 %) Basalzellkarzinome. Bezüglich der Malignität war der positive prädiktive Wert der blauen Farbe 63,9 % (95 % KI: 56,0-71,8 %). Unter blaugefärbten bösartigen Läsionen ist eine strukturlose periphere oder fleckige blaue Farbe ein Hinweis auf Melanome, während blaue Schollen auf ein Basalzellkarzinom hinweisen. Als Fallstricke können sich seborrhoische Keratosen erweisen, die eine Blaufärbung zeigen können, sowie einige Nävi, vor allem kombinierte. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  10. Tuning the van der Waals Interaction of Graphene with Molecules via Doping.

    PubMed

    Huttmann, Felix; Martínez-Galera, Antonio J; Caciuc, Vasile; Atodiresei, Nicolae; Schumacher, Stefan; Standop, Sebastian; Hamada, Ikutaro; Wehling, Tim O; Blügel, Stefan; Michely, Thomas

    2015-12-04

    We use scanning tunneling microscopy to visualize and thermal desorption spectroscopy to quantitatively measure that the binding of naphthalene molecules to graphene, a case of pure van der Waals interaction, strengthens with n and weakens with p doping of graphene. Density-functional theory calculations that include the van der Waals interaction in a seamless, ab initio way accurately reproduce the observed trend in binding energies. Based on a model calculation, we propose that the van der Waals interaction is modified by changing the spatial extent of graphene's π orbitals via doping.

  11. Europäische Leitlinien (S1) für die Anwendung von hochdosierten intravenösen Immunglobulinen in der Dermatologie.

    PubMed

    Enk, Alexander; Hadaschik, Eva; Eming, Rüdiger; Fierlbeck, Gerhard; French, Lars; Girolomoni, Giampiero; Hertl, Michael; Jolles, Stephen; Karpati, Sarolta; Steinbrink, Kerstin; Stingl, Georg; Volc-Platzer, Beatrix; Zillikens, Detlef

    2017-02-01

    Die Behandlung schwerer dermatologischer Autoimmunerkrankungen und der toxischen epidermalen Nekrolyse (TEN) mit hochdosierten intravenösen Immunglobulinen (IVIg) ist ein bewährtes therapeutisches Verfahren in der Dermatologie. Da eine IVIg-Therapie in der Regel nur bei seltenen Erkrankungen oder bei schweren Fällen in Betracht gezogen wird, stützt sich die Anwendung von Immunglobulinen zumeist nicht auf Daten aus randomisierten kontrollierten Studien, wie sie in der evidenzbasierten Medizin erforderlich sind. Da Indikationen für die Anwendung von IVIg selten sind, ist es unwahrscheinlich, dass solche Studien in absehbarer Zeit durchgeführt werden. Wegen der hohen Kosten für IVIg im First-Line-Einsatz wurden die ersten klinischen Leitlinien für die Anwendung von IVIg bei dermatologischen Erkrankungen im Jahr 2008 herausgegeben und im Jahr 2011 überarbeitet. Diese europäischen Leitlinien wurden von einer Gruppe durch das EDF und die EADV benannter Experten erarbeitet. Die Leitlinien wurden erstellt, um die derzeit als wirksam erachteten Behandlungsindikationen zu aktualisieren und die für die Anwendung von IVIg bei dermatologischen Autoimmunerkrankungen und TEN vorliegenden Daten zusammenzufassen. Die vorliegenden Leitlinien repräsentieren die einvernehmlichen Meinungen und Definitionen von Experten zur Anwendung von IVIg, die die aktuell publizierten Daten widerspiegeln, und sollen als Entscheidungshilfe für den Einsatz von IVIg bei dermatologischen Erkrankungen dienen. © 2017 The Authors | Journal compilation © Blackwell Verlag GmbH, Berlin.

  12. Verbesserung der Prozessbedingungen beim Einlippentiefbohren durch unterschiedliche Formen der Vorschubmodulation

    NASA Astrophysics Data System (ADS)

    Eisseler, Rocco

    Das Tiefbohren mit Einlippenwerkzeugen ist bei vielen Anwendungen das Verfahren der ersten Wahl, vor allem wenn kleine und kleinste Bohrungsdurchmesser, ein sehr großes Verhältnis zwischen Bohrtiefe und Durchmesser (l/D) und eine hohe Bearbeitungsqualität gefordert werden. Der erreichbare Durchmesserbereich des Verfahrens liegt zwischen D = 0,5 mm und 40 mm, wobei die möglichen Bohrtiefen von l = 3 x D bis 250 x D reichen. Diese Werte beziehen sich auf das Vollbohren, beim Aufbohren können noch größere Durchmesser erreicht werden [1]. Die erreichbare Oberflächenqualität ist so hoch, dass in den meisten Fällen auf eine nachfolgende Feinbearbeitung verzichtet werden kann.

  13. Characterization of AusA: A Dimodular Nonribosomal Peptide Synthetase Responsible for Production of Aureusimine Pyrazinones

    PubMed Central

    Wilson, Daniel J.; Shi, Ce; Teitelbaum, Aaron M.; Gulick, Andrew M.; Aldrich, Courtney C.

    2013-01-01

    Aureusimines have been identified as potential virulence factors in Staphylococcus aureus. These pyrazinone secondary metabolites are produced by a nonribosomal peptide synthetase (NRPS) annotated as AusA. We report the overproduction of AusA as a 277 kDa soluble protein with the bimodular architecture A1–T1–C–A2–T2–R. The substrate specificity of each adenylation (A) domain was initially probed using an ATP–pyrophosphate exchange assay with A-domain selective bisubstrate inhibitors to chemically knock-out each companion A-domain. The activity of AusA was then reconstituted in vitro and shown to produce all naturally occurring aureusimines and non-natural pyrazinone products with kcat values ranging from 0.4 to 1.3 min−1. Steady-state kinetic parameters were determined for all substrates and cofactors providing the first comprehensive steady-state characterization of a NRPS employing a product formation assay. The KM values for the amino acids were up to 60-fold lower with the product formation assay versus the ATP–pyrophosphate exchange assay, most commonly used to assess A-domain substrate specificity. The C-terminal reductase (R) domain catalyzes reductive release of the dipeptidyl intermediate leading to formation of an amino aldehyde that cyclizes to a dihydropyrazinone. We show oxidation to the final pyrazinone heterocycle is spontaneous. The activity and specificity of the R-domain was independently investigated using a NADPH consumption assay. AusA is a minimal autonomous two-module NRPS that represents an excellent model system for further kinetic and structural characterization. PMID:23302043

  14. Spherical and hyperspherical harmonics representation of van der Waals aggregates

    NASA Astrophysics Data System (ADS)

    Lombardi, Andrea; Palazzetti, Federico; Aquilanti, Vincenzo; Grossi, Gaia; Albernaz, Alessandra F.; Barreto, Patricia R. P.; Cruz, Ana Claudia P. S.

    2016-12-01

    The representation of the potential energy surfaces of atom-molecule or molecular dimers interactions should account faithfully for the symmetry properties of the systems, preserving at the same time a compact analytical form. To this aim, the choice of a proper set of coordinates is a necessary precondition. Here we illustrate a description in terms of hyperspherical coordinates and the expansion of the intermolecular interaction energy in terms of hypersherical harmonics, as a general method for building potential energy surfaces suitable for molecular dynamics simulations of van der Waals aggregates. Examples for the prototypical case diatomic-molecule-diatomic-molecule interactions are shown.

  15. Energy.

    ERIC Educational Resources Information Center

    Online-Offline, 1998

    1998-01-01

    This issue focuses on the theme of "Energy," and describes several educational resources (Web sites, CD-ROMs and software, videos, books, activities, and other resources). Sidebars offer features on alternative energy, animal energy, internal combustion engines, and energy from food. Subthemes include harnessing energy, human energy, and…

  16. Energy.

    ERIC Educational Resources Information Center

    Online-Offline, 1998

    1998-01-01

    This issue focuses on the theme of "Energy," and describes several educational resources (Web sites, CD-ROMs and software, videos, books, activities, and other resources). Sidebars offer features on alternative energy, animal energy, internal combustion engines, and energy from food. Subthemes include harnessing energy, human energy, and…

  17. Quantitative Analyse und Visualisierung der Herzfunktionen

    NASA Astrophysics Data System (ADS)

    Sauer, Anne; Schwarz, Tobias; Engel, Nicole; Seitel, Mathias; Kenngott, Hannes; Mohrhardt, Carsten; Loßnitzer, Dirk; Giannitsis, Evangelos; Katus, Hugo A.; Meinzer, Hans-Peter

    Die computergestützte bildbasierte Analyse der Herzfunktionen ist mittlerweile Standard in der Kardiologie. Die verfügbaren Produkte erfordern meist ein hohes Maß an Benutzerinteraktion und somit einen erhöhten Zeitaufwand. In dieser Arbeit wird ein Ansatz vorgestellt, der dem Kardiologen eine größtenteils automatische Analyse der Herzfunktionen mittels MRT-Bilddaten ermöglicht und damit Zeitersparnis schafft. Hierbei werden alle relevanten herzphysiologsichen Parameter berechnet und mithilfe von Diagrammen und Graphen visualisiert. Diese Berechnungen werden evaluiert, indem die ermittelten Werte mit manuell vermessenen verglichen werden. Der hierbei berechnete mittlere Fehler liegt mit 2,85 mm für die Wanddicke und 1,61 mm für die Wanddickenzunahme immer noch im Bereich einer Pixelgrösse der verwendeten Bilder.

  18. Welche Fragen konnen aus einer Gemeinsamen Interpretation der Befunde aus PISA and IGLU Fundiert Beantwortet Werden? (To Which Questions Does a Combined Interpretation of the Results Yielded by both PISA and IGLU Provide Well-Grounded Answers?).

    ERIC Educational Resources Information Center

    Bos, Wilfried; Lankes, Eva-Maria; Prenzel, Manfred; Schwippert, Knut; Walther, Gerd; Valtin, Renate; Voss, Andreas

    2003-01-01

    Discusses the International Survey on Reading Abilities in Primary School (IGLU) and its data on achievement in reading, mathematics, and natural science. Compares this data to that collected by the Program for International Student Assessment (PISA). Identifies achievement relevant correlations such as gender, migration background, socioeconomic…

  19. Vernachlässigte klinische Merkmale der follikulotropen Mycosis fungoides: eine große klinische Fallserie.

    PubMed

    Baykal, Can; Atci, Tugba; Ozturk Sari, Sule; Polat Ekinci, Algun; Buyukbabani, Nesimi

    2017-03-01

    Als seltene Form der Mycosis fungoides (MF), ist die follikulotrope MF (FMF) durch ein breites Spektrum klinischer Symptome gekennzeichnet. Dazu gehören, neben den vorherrschenden follikulären Läsionen, auch viele atypische Manifestationen. Das Ziel der vorliegenden Studie war eine klinische Bewertung von FMF-Patienten, unter besonderer Berücksichtigung von vernachlässigten dermatologischen Merkmalen. Insgesamt wurden 27 FMF-Patienten aus dem 572 Patienten umfassenden MF-Register unserer Abteilung retrospektiv bezüglich ihrer Demographie sowie der klinischen Merkmale, Behandlungsformen, Nachsorge und Therapieergebnisse bewertet. Neben den bekannten klinischen Symptomen der FMF fanden wir Lichen-spinulosus-artige Läsionen mit begleitender Hypopigmentierung (n = 3) und Alopezie (n = 2), infiltrierte/erhabene, erythematöse Plaques im Gesicht, die zunächst als Lupus tumidus angesehen wurden (n = 2), pseudotumorale Läsionen, die klinisch eine MF im Tumorstadium vortäuschten (n = 1), dauerhafte Exkoriationen (n = 1), erythematöse, Rosazea-artige Papeln im Gesicht (n = 1) sowie kuppelförmige, asymptomatische, mit Muzin gefüllte (in der Histologie) Papeln/Knoten (n = 2), die andere krankheitsbedingte Läsionen überlagerten. Es kamen mehrere Therapieansätze mit unterschiedlichem Ergebnis zur Anwendung. Acht (29,6 %) Patienten hatten FMF im Spätstadium. Das Bewusstsein für vernachlässigte klinische Symptome kann wesentlich dazu beitragen, verspätete Diagnosen dieser aggressiven MF-Variante zu verringern. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  20. Friedrich Möglich - sein Beitrag zum Aufbau der Physik in der DDR. Friedrich Möglich - langjähriger Mitherausgeber und Chefredakteur der Annalen der Physik

    NASA Astrophysics Data System (ADS)

    Rompe, Robert

    Friedrich Möglich, ein Schüler von Max von Laue und Erwin Schrödinger, übernahm 1947 die Chefredaktion der Annalen der Physik.Translated AbstractFriedrich Möglich - His Contributions to the Formation of Physics in GDRFriedrich Möglich a student of Max von Laue and Erwin Schrödinger took over as editor in chief of Annalen der Physik in 1947.

  1. Sterblichkeit: der paradoxe Kunstgriff des Lebens - Eine Betrachtung vor dem Hintergrund der modernen Biologie

    NASA Astrophysics Data System (ADS)

    Verbeek, Bernhard

    Leben gibt es auf der Erde seit fast 4 Mio. Jahren, trotz allen Katastrophen. Die Idee des Lebens scheint unsterblich. Der Tod aber offenbar auch. Jedes Lebewesen ist davon bedroht, ja für Menschen und andere "höhere“ Lebewesen ist er im Lebensprogramm eingebaut - todsicher. Diese Tatsache ist alles andere als selbstverständlich. Ist sie überhaupt kompatibel mit dem Prinzip der Evolution, nach dem der am besten Angepasste überlebt?

  2. Van der Waals Interactions in Aspirin

    NASA Astrophysics Data System (ADS)

    Reilly, Anthony; Tkatchenko, Alexandre

    2015-03-01

    The ability of molecules to yield multiple solid forms, or polymorphs, has significance for diverse applications ranging from drug design and food chemistry to nonlinear optics and hydrogen storage. In particular, aspirin has been used and studied for over a century, but has only recently been shown to have an additional polymorphic form, known as form II. Since the two observed solid forms of aspirin are degenerate in terms of lattice energy, kinetic effects have been suggested to determine the metastability of the less abundant form II. Here, first-principles calculations provide an alternative explanation based on free-energy differences at room temperature. The explicit consideration of many-body van der Waals interactions in the free energy demonstrates that the stability of the most abundant form of aspirin is due to a subtle coupling between collective electronic fluctuations and quantized lattice vibrations. In addition, a systematic analysis of the elastic properties of the two forms of aspirin rules out mechanical instability of form II as making it metastable.

  3. Ganzheitliche Digitalisierungsansätze im Stadtwerk: Von der Strategie bis zur Umsetzung

    NASA Astrophysics Data System (ADS)

    Dudenhausen, Roman; Hahn, Heike

    Digitalisierung muss im Stadtwerk dazu führen, Kundenerwartungen, die heutzutage schon vielfach durch digitales Know-how und Erfahrungen geprägt sind, in einzigartiger Weise zu entsprechen - in Form digitaler Kundenkontaktpunkte, automatisierter Prozesse oder plattformbasierter Geschäftsmodelle. Eine große Rolle spielen dabei unternehmensweit nutzbare Informationen, die eine 360-Grad-Sicht auf den Kunden ermöglichen. Nur in dieser Kombination werden sich nachhaltig Wettbewerbsvorteile generieren lassen. Manch ein Kunde wird die Lust, einen Prozess zu Ende zu gehen, schon vor dem Abschluss verlieren, wenn er nicht unmittelbar und ohne die digitale Welt zu verlassen zum Ziel kommt. Eine nur "halb digitale Kundenerfahrung" wird weder zu Neugeschäft noch zur positiven emotionalen Bindung zwischen Kunden und Stadtwerk führen. Nicht zu unterschätzen sind zudem Erwartungen hinsichtlich zukünftiger Geschäftsmodelle, aus denen sich disruptive Bedrohungen für die herkömmlichen Strom- und Gasangebote ergeben werden. Erste innovative Ansätze finden sich bereits im Markt, die erahnen lassen, dass zurzeit viel diskutierte Technologien wie die Blockchain nicht mehr nur hypothetischer Natur sind. Die Auseinandersetzung mit der Digitalisierung erfolgt dabei sinnvollerweise in einem unternehmensweit abgestimmten Rahmen, der eine zielgerichtete und ganzheitliche Vorgehensweise ermöglicht.

  4. An Analysis of the DER Adoption Climate in Japan UsingOptimization Results for Prototype Buildings with U.S. Comparisons

    SciTech Connect

    Zhou, Nan; Marnay, Chris; Firestone, Ryan; Gao, Weijun; Nishida,Masaru

    2006-06-16

    This research demonstrates economically optimal distributedenergy resource (DER) system choice using the DER choice and operationsoptimization program, the Distributed Energy Resources Customer AdoptionModel (DER-CAM). DER-CAM finds the optimal combination of installedequipment given prevailing utility tariffs and fuel prices, siteelectrical and thermal loads (including absorption cooling), and a menuof available equipment. It provides a global optimization, albeitidealized, that shows how site useful energy loads can be served atminimum cost. Five prototype Japanese commercial buildings are examinedand DER-CAM is applied to select the economically optimal DER system foreach. Based on the optimization results, energy and emission reductionsare evaluated. Significant decreases in fuel consumption, carbonemissions, and energy costs were seen in the DER-CAM results. Savingswere most noticeable in the prototype sports facility, followed by thehospital, hotel, and office building. Results show that DER with combinedheat and power equipment is a promising efficiency and carbon mitigationstrategy, but that precise system design is necessary. Furthermore, aJapan-U.S. comparison study of policy, technology, and utility tariffsrelevant to DER installation is presented.

  5. Untersuchung der Richtwirkung der Einkopplung von ebenen Wellen in eine Leitung

    NASA Astrophysics Data System (ADS)

    Magdowski, M.; Vick, R.

    2013-07-01

    Elektrische Leitungen und Kabel stellen häufig die Haupteinfallstore für elektromagnetische Felder in die daran angeschlossenen Geräte und Systeme dar. Für die Einkopplung einer ebenen Welle kann der in eine Leitung eingekoppelte Strom unter bestimmten Voraussetzungen mit Hilfe der Leitungstheorie sehr effizient bestimmt werden. Er hängt dabei von den Abmessungen der Leitung, den Leitungsabschlüssen sowie der Amplitude, der Wellenlänge und der Einfallsrichtung der ebenen Welle ab. In dieser Arbeit wird die Abhängigkeit der Einkopplung von der Einfallsrichtung näher untersucht. Dazu werden Richtdiagramme der Einkopplung berechnet, dargestellt und hinsichtlich der mittleren und maximalen Einkopplung über alle Einfallsrichtungen und Polarisationen ausgewertet. Die Ergebnisse werden genutzt, um die maximale Direktivität der Einkopplung in eine Leitung zu bestimmen. Fasst man die Einkopplung externer Felder in eine Leitung als einen Störfestigkeitstest auf, so kann die maximale Direktivität benutzt werden, um einen Vergleich zwischen unterschiedlichen Messumgebungen wie Absorberhallen und Modenverwirbelungskammern herzustellen.

  6. Energy Policy Case Study - California: Renewables and Distributed Energy Resources

    SciTech Connect

    Homer, Juliet S.; Bender, Sadie R.; Weimar, Mark R.

    2016-09-19

    The purpose of this document is to present a case study of energy policies in California related to power system transformation and renewable and distributed energy resources (DERs). Distributed energy resources represent a broad range of technologies that can significantly impact how much, and when, electricity is demanded from the grid. Key policies and proceedings related to power system transformation and DERs are grouped into the following categories: 1.Policies that support achieving environmental and climate goals 2.Policies that promote deployment of DERs 3.Policies that support reliability and integration of DERs 4.Policies that promote market animation and support customer choice. Major challenges going forward are forecasting and modeling DERs, regulatory and utility business model issues, reliability, valuation and pricing, and data management and sharing.

  7. Physisorption of benzene on a tin dioxide surface: van der Waals interaction

    NASA Astrophysics Data System (ADS)

    Viitala, Matti; Kuisma, Mikael; Rantala, Tapio T.

    2012-02-01

    An adsorption study of the benzene molecule on SnO2 (110) surfaces with the density functional theory is extended to include the van der Waals interaction. We compare adsorption onto two model surfaces of SnO2, oxygen rich (stoichiometric) and oxygen poor (reduced), considered as limiting cases of varying oxygen abundance. With the chosen van der Waals approach [M. Dion, H. Rydberg, E. Schröder, D. C. Langreth, and B. I. Lundqvist, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.92.246401 92, 246401 (2004)] it is found that on the stoichiometric surface, where binding has both a covalent nature and an ionic nature, with the addition of the van der Waals interaction the adsorption energy becomes somewhat stronger. However, on the reduced surface, where binding was earlier predicted to be more physisorptionlike by using a standard generalized gradient approximation (GGA) approach, the van der Waals interaction increases the adsorption energy by a larger factor. Furthermore, three different local-density approximation and GGA functionals are compared, as corrected with the van der Waals scheme. It is found that the correction brings those three to reasonably similar descriptions of adsorption on both surfaces.

  8. AusSCORE II in predicting 30-day mortality after isolated coronary artery bypass grafting in Australia and New Zealand.

    PubMed

    Billah, Baki; Huq, Molla M; Smith, Julian A; Sufi, Fahim; Tran, Lavinia; Shardey, Gilbert C; Reid, Christopher M

    2014-11-01

    To update the Australian System for Cardiac Operative Risk Evaluation (AusSCORE) model for operative estimation of 30-day mortality risk after isolated coronary artery bypass grafting in the Australian population. Data were collected by the Australian and New Zealand Society of Cardiac and Thoracic Surgeons registry from 2001 to 2011 in 25 hospitals. A total of 31,250 patients underwent isolated coronary artery bypass grafting and the outcome was 30-day mortality. A total of 2154 (6.9%) patients had 1 or multiple missing values. Missing values were estimated assuming missing completely at random and logistic regression with a generalized estimating equation was used to address within-hospital variance. Bootstrapping methods were used to construct and validate the updated model (AusSCORE II). Also the model was validated on an out-of-creation sample of 4700 patients who underwent bypass surgery in 2012. The average age of the patients was 65.6±12.9 years and 78.6% were male. Thirteen variables were selected in the updated model. The bootstrap discrimination and calibration of the AusSCORE II was very good (receiver operating characteristics [ROC], 82.0%; slope calibration, 0.987). The overall observed/AusSCORE II predicted mortality was 1.63% compared with the original AusSCORE predicted mortality of 1.01%. The validation of the AusSCORE II on the out-of-sample data also showed a high performance of the model (ROC, 84.5%; Hosmer-Lemoshow P value, .7654). The AusSCORE II model provides improved prediction of 30-day mortality and successfully stratifies patient risk. The model will be useful to improve the preoperative consultation regarding risk stratification in terms of 30-day mortality. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  9. Sequence polymorphisms of Der f 1, Der p 1, Der f 2 and Der p 2 from Korean house dust mite isolates.

    PubMed

    Jeong, Kyoung Yong; Lee, In-Yong; Yong, Tai-Soon; Lee, Jae-Hyun; Kim, Eun-Jin; Lee, Joo-Shil; Hong, Chein-Soo; Park, Jung-Won

    2012-09-01

    Amino acid sequence variations have possible influences on the allergenicity of allergens and may be important factors in allergen standardization. This study was undertaken to investigate the sequence polymorphisms of group 1 and 2 allergens from Korean isolates of the house dust mites Dermatophagoides farinae and D. pteronyssinus. cDNA sequences encoding group 1 and 2 allergens were amplified by RT-PCR and compared the deduced amino acid sequences. Der f 1.0101, which appeared in 64.0 % of the 50 sequences analyzed, was found to be predominant. Among the Der p 1 sequences, Der p 1.0102 and 1.0105 were predominant (58 %). Among the Der f 2 sequences, Der f 2.0102 (40.7 %) and a new variant with Gly at position 42 (27.8 %) were predominant. The deduced amino acid sequences of 60 Der p 2 clones were examined, and 28 variants with 1-5 amino acid substitutions were found. Interestingly, all of the Der p 2 sequences had Thr instead of Lys at position 49. Two variants (Leu40, Thr49, and Asn114 (26.6 %); Val40, Thr49, and Asn114 (20.0 %)) were found to be the most predominant forms of Der p 2. Der p 1 has a high rate of sporadic substitutions and the group 2 allergens show a more regular pattern with orderly associations of amino acid substitutions. Der f 1 and Der p 2 from Korean mite isolates have unique amino acid sequence polymorphisms. These findings provide important data for house dust mite allergen standardization.

  10. Von Humboldt bis Einstein. Berlin als Weltzentrum der exakten Wissenschaften.

    NASA Astrophysics Data System (ADS)

    Meschkowski, H.

    Contents: 1. Die Anfänge. 2. Die Ära Dirichlet-Jacobi. 3. Der Ausbau der experimentellen Naturwissenschaften. 4. Alexander von Humboldt. 5. Berlin wird "Weltzentrum" der Mathematik. 6. Die Ära Helmholtz. 7. Neue Arbeitsweisen der Astronomie. 8. Chemie: Forschung und Industrie. 9. Max Planck. 10. Ins technische Zeitalter. 11. Zur Mathematik der zwanziger Jahre. 12. Albert Einstein. 13. Fortschritte der Grundlagenforschung. 14. Erwin Schrödinger: Physiker, Philosoph und Poet. 15. Zum Schluß.

  11. Van der Waals density functional: An appropriate exchange functional

    NASA Astrophysics Data System (ADS)

    Cooper, Valentino R.

    2010-04-01

    In this Rapid Communication, an exchange functional which is compatible with the nonlocal Rutgers-Chalmers correlation functional [van der Waals density functional (vdW-DF)] is presented. This functional, when employed with vdW-DF, demonstrates remarkable improvements on intermolecular separation distances while further improving the accuracy of vdW-DF interaction energies. The key to the success of this three-parameter functional is its reduction in short-range exchange repulsion through matching to the gradient expansion approximation in the slowly varying/high-density limit while recovering the large reduced gradient, s , limit set in the revised Perdew-Burke-Ernzerhof (revPBE) exchange functional. This augmented exchange functional could be a solution to long-standing issues of vdW-DF lending to further applicability of density-functional theory to the study of relatively large, dispersion bound (van der Waals) complexes.

  12. Der Kalte Krieg in der Peripherie Griechische Physiker und Atomenergie nach dem Zweiten Weltkrieg

    NASA Astrophysics Data System (ADS)

    Vlahakis, George N.

    Die vorliegende Arbeit analysiert Ansichten griechischer Physiker zur Atomenergie und deren mögliche Anwendung nach dem Zweiten Weltkrieg, insbesondere während des Kalten Kriegs. Einerseits werden Ansichten von Physik- Professoren griechischer Universitäten präsentiert - beispielsweise von Dimitrios Hondros, der Student von Arnold Sommerfeld und Mitarbeiter von Peter Debye in München war, und andererseits wird die Politik der griechischen Regierung für die Etablierung eines Forschungsinstitutes diskutiert, das der Entwicklung der Atomenergie dienen sollte; ebenfalls wird eine öffentliche Meinungsumfrage zu diesen Thema, die in den Tageszeitungen der damaligen Zeit präsentiert wurde, diskutiert.

  13. Assessing the long-term species composition predicted by PrognAus.

    PubMed

    Huber, Markus O

    2010-01-25

    Tree growth models are supposed to contain stand growth laws as so called "emergent properties" which derive from interactions of individual-tree growth and mortality functions. This study investigates whether the evolving tree species composition in a long term simulation by the distance-independent tree growth model PrognAus matches the species composition of the potential natural vegetation type which is expected to occur if one refrains from further management interventions and major disturbances, climate change, and changes in site conditions can be excluded. For this purpose the development of 6933 sample plots of the Austrian National Forest Inventory was predicted for 2500 years. The resulting species proportions, derived from volume per hectare of 15 tree species or species groups, were used to classify every sample plot according to potential natural forest types, following a classification scheme based on expert knowledge. These simulated potential natural vegetation types were compared with expert reconstructions of the sample plots of the Austrian National Forest Inventory. A total of 5789 plots were actually classified with the scheme; in 33% of the cases the classification on the basis of the PrognAus-simulations was identical with the classification by the Austrian National Forest Inventory. A predominantly correct classification was achieved for the subalpine Picea abies-type and the Fagus sylvatica-type although PrognAus showed a tendency to overestimate the proportion of F. sylvatica and P. abies. Weaknesses in the ability to simulate forest types dominated by Quercus spp., Acer spp., and Pinus sylvestris were identified. This shortcoming might be caused by the mortality model which allows a larger diameter at breast height for F. sylvatica or by the ingrowth model whose terms for the consideration of inter-specific competition may lead to a disadvantage of Quercus spp., P. sylvestris, and Abies alba. Moreover, the ingrowth model might be

  14. Assessing the long-term species composition predicted by PrognAus

    PubMed Central

    Huber, Markus O.

    2010-01-01

    Tree growth models are supposed to contain stand growth laws as so called “emergent properties” which derive from interactions of individual-tree growth and mortality functions. This study investigates whether the evolving tree species composition in a long term simulation by the distance-independent tree growth model PrognAus matches the species composition of the potential natural vegetation type which is expected to occur if one refrains from further management interventions and major disturbances, climate change, and changes in site conditions can be excluded. For this purpose the development of 6933 sample plots of the Austrian National Forest Inventory was predicted for 2500 years. The resulting species proportions, derived from volume per hectare of 15 tree species or species groups, were used to classify every sample plot according to potential natural forest types, following a classification scheme based on expert knowledge. These simulated potential natural vegetation types were compared with expert reconstructions of the sample plots of the Austrian National Forest Inventory. A total of 5789 plots were actually classified with the scheme; in 33% of the cases the classification on the basis of the PrognAus-simulations was identical with the classification by the Austrian National Forest Inventory. A predominantly correct classification was achieved for the subalpine Picea abies-type and the Fagus sylvatica-type although PrognAus showed a tendency to overestimate the proportion of F. sylvatica and P. abies. Weaknesses in the ability to simulate forest types dominated by Quercus spp., Acer spp., and Pinus sylvestris were identified. This shortcoming might be caused by the mortality model which allows a larger diameter at breast height for F. sylvatica or by the ingrowth model whose terms for the consideration of inter-specific competition may lead to a disadvantage of Quercus spp., P. sylvestris, and Abies alba. Moreover, the ingrowth model might be

  15. Van der Waals interaction between two crossed carbon nanotubes.

    PubMed

    Zhbanov, Alexander I; Pogorelov, Evgeny G; Chang, Yia-Chung

    2010-10-26

    The analytical expressions for the van der Waals potential energy and force between two crossed carbon nanotubes are presented. The Lennard-Jones potential between pairs of carbon atoms and the smeared-out approximation suggested by L. A. Girifalco (J. Phys. Chem. 1992, 96, 858) were used. The exact formula is expressed in terms of rational and elliptical functions. The potential and force for carbon nanotubes were calculated. The uniform potential curves for single- and multiwall nanotubes were plotted. The equilibrium distance, maximal attractive force, and potential energy have been evaluated.

  16. Photovoltaic DER System Could Save USPS $25,000 per Year in Marina del Rey, California

    SciTech Connect

    Not Available

    2002-11-01

    In numerous projects, government agencies are demonstrating the economic and environmental value of using distributed energy resources (DER) to provide reliable electricity for Federal facilities. These projects also show how renewable DER systems such as photovoltaics (PV) can be effectively integrated into utility power grids to provide added power during peak demand periods in populous regions and states. This four-page case study describes a recent project in which the United States Postal Service (USPS) worked with the U.S. Department of Energy (DOE) Federal Energy Management Program (FEMP), a national laboratory, the local utility, and a private company to install a PV DER system at the USPS Marina Processing and Distribution Center in Inglewood, California. This system is expected to shave 10% off the facility's 1.2-megawatt peak power demand and save more $25,000 per year in utility costs.

  17. Reactivity enhancement of ultracold O(3P)+H2 collisions by van der Waals interactions

    NASA Astrophysics Data System (ADS)

    Weck, P. F.; Balakrishnan, N.

    2005-10-01

    The role of van der Waals forces in O(P3)+H2(υ =1,j=0) collisions is investigated theoretically at low and ultralow temperatures. Quantum scattering calculations have been performed for zero total angular momentum using the lowest London-Eyring-Polanyi-Sato double-polynomial A″3 potential-energy surface reported by [Rogers et al., J. Phys. Chem. A 104, 2308 (2000)] and its recent BMS1 and BMS2 extensions developed by [Brandão et al., J. Chem. Phys. 121, 8861 (2004)] which provide a more accurate treatment of the van der Waals interaction. Our calculations show that van der Waals forces strongly influence chemical reactivity at ultracold translational energies. The presence of a zero-energy resonance for the BMS1 surface is found to enhance reactivity in the ultracold regime and shift the Wigner threshold to lower temperatures.

  18. POST-CLOSURE INSPECTION REPORT FOR CORRECTIVE ACTION UNIT 333: U-3auS DISPOSAL SITE, NEVADA TEST SITE, NEVADA FOR THE PERIOD JULY 2005-JUNE 2006

    SciTech Connect

    2006-08-01

    Corrective Action Unit (CAU) 333, U-3auS Disposal Site, is a closed construction landfill located in Area 3 of the Nevada Test Site (NTS). The closure of this site was approved by the Nevada Division of Environmental Protection (NDEP) in a letter to the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office (NNSA/NV) dated June 27, 2001. Post-closure requirements are described in a letter from NNSA/NV to NDEP dated October 9, 2001, and were approved by the NDEP in a letter dated November 5, 2001. This report covers the period July 2005 through June 2006 and consists of copies of the inspection checklist and field notes, repair records (if any), photographs, and recommendations and conclusions.

  19. Heterologous Expression of Der Homologs in an Escherichia coli der Mutant and Their Functional Complementation

    PubMed Central

    Choi, Eunsil; Kang, Nalae; Jeon, Young; Pai, Hyun-Sook

    2016-01-01

    ABSTRACT The unique Escherichia coli GTPase Der (double Era-like GTPase), which contains tandemly repeated GTP-binding domains, has been shown to play an essential role in 50S ribosomal subunit biogenesis. The depletion of Der results in the accumulation of precursors of 50S ribosomal subunits that are structurally unstable at low Mg2+ concentrations. Der homologs are ubiquitously found in eubacteria. Conversely, very few are conserved in eukaryotes, and none is conserved in archaea. In the present study, to verify their conserved role in bacterial 50S ribosomal subunit biogenesis, we cloned Der homologs from two gammaproteobacteria, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium; two pathogenic bacteria, Staphylococcus aureus and Neisseria gonorrhoeae; and the extremophile Deinococcus radiodurans and then evaluated whether they could functionally complement the E. coli der-null phenotype. Only K. pneumoniae and S. Typhimurium Der proteins enabled the E. coli der-null strain to grow under nonpermissive conditions. Sucrose density gradient experiments revealed that the expression of K. pneumoniae and S. Typhimurium Der proteins rescued the structural instability of 50S ribosomal subunits, which was caused by E. coli Der depletion. To determine what allows their complementation, we constructed Der chimeras. We found that only Der chimeras harboring both the linker and long C-terminal regions could reverse the growth defects of the der-null strain. Our findings suggest that ubiquitously conserved essential GTPase Der is involved in 50S ribosomal subunit biosynthesis in various bacteria and that the linker and C-terminal regions may participate in species-specific recognition or interaction with the 50S ribosomal subunit. IMPORTANCE In Escherichia coli, Der (double Era-like GTPase) is an essential GTPase that is important for the production of mature 50S ribosomal subunits. However, to date, its precise role in ribosome biogenesis has not been

  20. An approximate quantal treatment to obtain the energy levels of tetra-atomic X ṡṡṡ I2 ṡṡṡ Y van der Waals clusters (X,Y=He,Ne)

    NASA Astrophysics Data System (ADS)

    García-Vela, A.; Villarreal, P.; Delgado-Barrio, G.

    1990-01-01

    The structure of tetra-atomic X ṡṡṡ I2 ṡṡṡ Y van der Waals (vdW) clusters, where X,Y=He,Ne, is studied using an approximate quantal treatment. In this model the above complexes are treated as like diatomic molecules with the rare-gas atoms playing the role of electrons in conventional diatomics. Then a H2-like molecular-orbital formalism is applied, choosing the discrete states of triatomic systems I2 ṡṡṡ X(Y) as molecular orbitals. Calculations at fixed configurations as well as including vdW bending motions restricted to the plane perpendicular to the I2 axis have been carried out for the sake of comparison with previous results. Finally, the restrictions are relaxed and the vdW bending motions are incorporated in a full way within the framework of a configuration interaction. The structure of these clusters is also studied through the probability density function.

  1. Energy

    ERIC Educational Resources Information Center

    Boyer, Ernest L.

    1977-01-01

    Schools must teach pupils about the wide nature of our energy dilemma and prepare them for a future in which not only will conservation of energy be essential, but also the conservation and preservation of our total natural resources. (JD)

  2. Energy balance and non-turbulent fluxes

    NASA Astrophysics Data System (ADS)

    Moderow, Uta; Feigenwinter, Christian; Bernhofer, Christian

    2010-05-01

    ) Flussbestimmung an komplexen Standorten, Tharandter Klimaprotokolle Band 8. Eigenverlag der Technischen Universität Dresden, 113 pp Feigenwinter C, Bernhofer C, Eichelmann U, Heinesch B, Hertel M, Janous D, Kolle O, Lagergren F, Lindroth A, Minerbi S, Moderow U, Mölder M, Montagnani L, Queck R, Rebmann C, Vestin P, Yernaux M, Zeri M, Ziegler W, Aubinet M (2008) Comparison of horizontal and vertical advective CO2 fluxes at three forest sites. Agric Forest Meteorol 148: 12-24 Foken T, Wimmer F, Mauder M, Thomas C, Liebethal C (2006) Some aspects of the energy balance closure problem. Atmos Chem Phys Discuss 6: 3381-3402 Laubach J (1996) Charakterisierung des turbulenten Austausches von Wärme, Wasserdampf und Kohlendioxid über niedriger Vegetation anhand von Eddy-Korrelations-Messungen. Band 3. Wissenschaftliche Mitteilungen aus dem Institut für Meteorologie der Universität Leipzig und dem Institut für Troposphärenforschung e.V, Leipzig, p 139 Moderow U, Aubinet M, Feigenwinter C, Kolle O, Lindroth A, Mölder M, Montagnani L, Rebmann C, Bernhofer C (2009) Available energy and energy balance closure at four coniferous sites across Europe. Theor Appl Meteorol 98: 397-412 Vogt R, Bernhofer C, Gay LW, Jaeger L, Parlow E (1996) The available energy over a Scots pine plantation: what's up for partitioning? Theor Appl Climatol 53:23-31

  3. Laboratory tests of IEC DER object models for grid applications.

    SciTech Connect

    Blevins, John D.; Menicucci, David F.; Byrd, Thomas, Jr.; Gonzalez, Sigifredo; Ginn, Jerry W.; Ortiz-Moyet, Juan

    2007-02-01

    This report describes a Cooperative Research and Development Agreement (CRADA) between Salt River Project Agricultural Improvement and Power District (SRP) and Sandia National Laboratories to jointly develop advanced methods of controlling distributed energy resources (DERs) that may be located within SRP distribution systems. The controls must provide a standardized interface to allow plug-and-play capability and should allow utilities to take advantage of advanced capabilities of DERs to provide a value beyond offsetting load power. To do this, Sandia and SRP field-tested the IEC 61850-7-420 DER object model (OM) in a grid environment, with the goal of validating whether the model is robust enough to be used in common utility applications. The diesel generator OM tested was successfully used to accomplish basic genset control and monitoring. However, as presently constituted it does not enable plug-and-play functionality. Suggestions are made of aspects of the standard that need further development and testing. These problems are far from insurmountable and do not imply anything fundamentally unsound or unworkable in the standard.

  4. Extrusion von ein- und mehrlumigen Katheterschläuchen aus thermoplastischen Kunststoffen

    NASA Astrophysics Data System (ADS)

    Wahl, Helmut

    In der Fertigung von medizinischen Katheterschläuchen werden thermoplastisch verarbeitbare Materialien wie z. B. Pebax, Polyamid, Polyurethan, Polyethylen oder Weich-PVC eingesetzt. Sämtliche zum Einsatz kommenden Materialien müssen für den medizinischen Einsatz zugelassen sein. Sie müssen in ihrer Zusammensetzung physiologisch unbedenklich sein.

  5. Cybersecurity for distributed energy resources and smart inverters

    SciTech Connect

    Qi, Junjian; Hahn, Adam; Lu, Xiaonan; Wang, Jianhui; Liu, Chen-Ching

    2016-12-01

    The increased penetration of distributed energy resources (DER) will significantly increase the number of devices that are owned and controlled by consumers and third parties. These devices have a significant dependency on digital communication and control, which presents a growing risk from cyber attacks. This paper proposes a holistic attack-resilient framework to protect the the integrated DER and the critical power grid infrastructure from malicious cyber attacks, helping ensure the secure integration of DER without harming the grid reliability and stability. Specifically, we discuss the architecture of the cyber-physical power system with a high penetration of DER and analyze the unique cybersecurity challenges introduced by DER integration. Next, we summarize important attack scenarios against DER, propose a systematic DER resilience analysis methodology, and develop effective and quantifiable resilience metrics and design principles. Lastly, we introduce attack prevention, detection, and response measures specifically designed for DER integration across cyber, physical device, and utility layers of the future smart grid.

  6. Symmetriebrechung und Emergenz in der Kosmologie.

    NASA Astrophysics Data System (ADS)

    Mainzer, K.

    Seit der Antike wird der Aufbau des Universums mit einfachen und regulären (symmetrischen) Grundstrukturen verbunden. Diese Annahme liegt selbst noch den Standardmodellen der relativistischen Kosmologie zugrunde. Demgegenüber läßt sich die Emergenz neuer Strukturen von den Elementarteilchen über Moleküle bis zu den komplexen Systemen des Lebens als Symmetriebrechung verstehen. Symmetriebrechung und strukturelle Komplexität bestimmen die kosmische Evolution. Damit zeichnet sich ein fachübergreifendes Forschungsprogramm von Physik, Chemie und Biologie ab, in dem die Evolution des Universums untersucht werden kann.

  7. Qualitätsmanagement in der Lebensmittelindustrie

    NASA Astrophysics Data System (ADS)

    Thorn, Volker

    Die wesentlichen Kunden der Lebensmittelindustrie sind der Einzel- und Großhandel und die Verbraucher. Jedes Unternehmen kann mittel- und langfristig nur existieren, wenn seine Kunden zufrieden sind. Kunden sind zufrieden, wenn ihre Erwartungen, die sie an Produkt, Service und Preis stellen, erfüllt werden. Also die bestimmte erwartete Qualität (Leistung) sichergestellt wird. Trotz aller Bemühungen und Anstrengungen der Anbieter, Qualitätsprodukte auf den Markt zu bringen, kames in den letzten Jahren immer wieder zu Lebensmittelskandalen.

  8. van der Waals interaction between a microparticle and a single-walled carbon nanotube

    SciTech Connect

    Blagov, E. V.; Mostepanenko, V. M.; Klimchitskaya, G. L.

    2007-06-15

    The Lifshitz-type formulas describing the free energy and the force of the van der Waals interaction between an atom (molecule) and a single-walled carbon nanotube are obtained. The single-walled nanotube is considered as a cylindrical sheet carrying a two-dimensional free-electron gas with appropriate boundary conditions on the electromagnetic field. The obtained formulas are used to calculate the van der Waals free energy and force between a hydrogen atom (molecule) and single-walled carbon nanotubes of different radii. Comparison studies of the van der Waals interaction of hydrogen atoms with single-walled and multiwalled carbon nanotubes show that depending on atom-nanotube separation distance, the idealization of graphite dielectric permittivity is already applicable to nanotubes with only two or three walls.

  9. Van der Waals Interactions Involving Proteins

    NASA Technical Reports Server (NTRS)

    Roth, Charles M.; Neal, Brian L.; Lenhoff, Abraham M.

    1996-01-01

    Van der Waals (dispersion) forces contribute to interactions of proteins with other molecules or with surfaces, but because of the structural complexity of protein molecules, the magnitude of these effects is usually estimated based on idealized models of the molecular geometry, e.g., spheres or spheroids. The calculations reported here seek to account for both the geometric irregularity of protein molecules and the material properties of the interacting media. Whereas the latter are found to fall in the generally accepted range, the molecular shape is shown to cause the magnitudes of the interactions to differ significantly from those calculated using idealized models. with important consequences. First, the roughness of the molecular surface leads to much lower average interaction energies for both protein-protein and protein-surface cases relative to calculations in which the protein molecule is approximated as a sphere. These results indicate that a form of steric stabilization may be an important effect in protein solutions. Underlying this behavior is appreciable orientational dependence, one reflection of which is that molecules of complementary shape are found to exhibit very strong attractive dispersion interactions. Although this has been widely discussed previously in the context of molecular recognition processes, the broader implications of these phenomena may also be important at larger molecular separations, e.g., in the dynamics of aggregation, precipitation, and crystal growth.

  10. Van der Waals Effects on semiconductor clusters.

    PubMed

    Li, Haisheng; Chen, Weiguang; Han, Xiaoyu; Li, Liben; Sun, Qiang; Guo, Zhengxiao; Jia, Yu

    2015-09-30

    Van der Waals (vdW) interactions play an important role on semiconductors in nanoscale. Here, we utilized first-principles calculations based on density functional theory to demonstrate the growth mode transition from prolate to multiunit configurations for Gen (n = 10-50) clusters. In agreement with the injected ion drift tube techniques that "clusters with n < 70 can be thought of as loosely bound assemblies of small strongly bound fragments (such as Ge7 and Ge10 )," we found these stable fragments are connected by Ge6 , Ge9 , or Ge10 unit (from bulk diamond), via strong covalent bonds. Our calculated cations usually fragment to Ge7 and Ge10 clusters, in accordance with the experiment results that the spectra Ge7 and Ge10 correspond to the mass abundance spectra. By controlling a germanium cluster with vdW interactions parameters in the program or not, we found that the vdW effects strengthen the covalent bond from different units more strikingly than that in a single unit. With more bonds between units than the threadlike structures, the multiunit structures have larger vdW energies, explaining why the isolated nanowires are harder to produce. © 2015 Wiley Periodicals, Inc.

  11. Van der Waals interactions involving proteins.

    PubMed Central

    Roth, C M; Neal, B L; Lenhoff, A M

    1996-01-01

    Van der Waals (dispersion) forces contribute to interactions of proteins with other molecules or with surfaces, but because of the structural complexity of protein molecules, the magnitude of these effects is usually estimated based on idealized models of the molecular geometry, e.g., spheres or spheroids. The calculations reported here seek to account for both the geometric irregularity of protein molecules and the material properties of the interacting media. Whereas the latter are found to fall in the generally accepted range, the molecular shape is shown to cause the magnitudes of the interactions to differ significantly from those calculated using idealized models, with important consequences. First, the roughness of the molecular surface leads to much lower average interaction energies for both protein-protein and protein-surface cases relative to calculations in which the protein molecule is approximated as a sphere. These results indicate that a form of steric stabilization may be an important effect in protein solutions. Underlying this behavior is appreciable orientational dependence, one reflection of which is that molecules of complementary shape are found to exhibit very strong attractive dispersion interactions. Although this has been widely discussed previously in the context of molecular recognition processes, the broader implications of these phenomena may also be important at larger molecular separations, e.g., in the dynamics of aggregation, precipitation, and crystal growth. Images FIGURE 3 PMID:8789115

  12. Energy

    DTIC Science & Technology

    2003-01-01

    Canada, Britain, and Spain. We found that the energy industry is not in crisis ; however, U.S. government policies, laws, dollars, and even public...CEIMAT (Centro de Investagaciones Energeticas , Medioambeintales y Tecnologicas) Research and development Page 3 of 28ENERGY 8/10/04http://www.ndu.edu...procurement or storage of standard, common use fuels. NATURAL GAS Natural gas, abundant globally and domestically, offers energy versatility among

  13. Werner Heisenberg zum 100. Geburtstag: Pionier der Quantenmechanik

    NASA Astrophysics Data System (ADS)

    Jacobi, Manfred

    2001-11-01

    Werner Heisenberg war eine der prägendsten Gestalten der Physik des 20. Jahrhunderts. Zu seinen wichtigsten Verdiensten gehören die Grundlegung der Quantenmechanik, die Formulierung der Unschärferelationen sowie die Beteiligung an der Ausarbeitung der Kopenhagener Deutung der Quantenmechanik. Darüber hinaus lieferte er Arbeiten von fundamentalem Charakter zur Theorie des Atomkerns, zur kosmischen Strahlung und zur Quantenfeldtheorie. Während des Krieges war er an den Arbeiten des Uranvereins beteiligt, der die Möglichkeit einer Entwicklung von Kernwaffen untersuchte, jedoch über Vorarbeiten zur Reaktorphysik nicht hinauskam. Wegen dieser Tätigkeit wurde er bei Kriegsende für einige Monate in England interniert. Nach seiner Rückkehr widmete er sich vor allem dem Aufbau der Physik in Deutschland, die während der NS-Zeit nahezu ihrer gesamten Substanz beraubt worden war.

  14. Studying at the Universities of the Armed Forces: Comparative Results from the 1999 Student Questionnaire (Studieren an den UniBw: Vergleichende Ergebnisse aus der Studentenbefragung 1999)

    DTIC Science & Technology

    2002-12-01

    Studenten 1999 UmiBw Hamburg UniBw Miinchen technische nichtt. technische nicdtt. Angaben in Prozent Fficher Ficher Ficher Ficher Gesamt Basis: Abe Befi’aten...GroBstadtszene? Tabelle 3 Frage: Dies 1I5t sich im einzelnen noch niher beschreiben: UniBw Studenten 1999 UniBw Hamburg UniBw Mfinchen technische nichtL... technische nichtt. Angaben in Prozent Ficher Ficher Ficher Ficher Gesamt Basis Alle Befragten 253 471 300 355 1382 stimme zu 42,70% 48,6% 37,3% 42,5

  15. Zur Kategorie der Modalitaet im Deutschen und Tschechischen aus konfrontativer Sicht (On the Category of Modality in German and Czech, Viewed in Comparison and Contrast)

    ERIC Educational Resources Information Center

    Grepl, Miroslav; Masarik, Zdenek

    1974-01-01

    Rejects a too-general classification of modality; would omit emotionality, affirmations and negations. Particles should not be indiscriminately classed as modals. Modality is divided into three aspects, which are then explained, with numerous comparative examples in Czech and German. (Text is in German.) (IFS/WGA)

  16. How Wilhelm Dilthey Influenced Popular Science Writing: Kurd Laßwitz's "Homchen. Ein Tiermärchen aus der oberen Kreide"

    NASA Astrophysics Data System (ADS)

    Azzouni, Safia

    In the second half of the nineteenth century, popularization of science appeared to be a necessity of the time. Scientists and politicians discussed the pros and cons of making scientific knowledge accessible to the public. The question of how and by whom popularization should be done was a common topic in newspapers and magazines of the time. Even though museums as well as zoological and botanical gardens played an important role in disseminating knowledge, it can be said that the popularization of science basically was (and probably still is) a "language-based event".1

  17. Results from Unit Medical Officer Health Reports during 1976 Calendar Year (Ergebnisse aus den Gesundheitsberichten der Truppenaerzte im Kalender Jahr 1976)

    DTIC Science & Technology

    1978-09-01

    personnel strergth . (1.975: 16,41,8 o/oo of actual personnel strength ; the figura was lowest in the navy with 3,314.8 o/oo of actual personnel...strength . I. infectious and parasite diseases (000-136); 32. tumors (growth’, (145-239); III . disorders of internal secretory glands, malnutrition and

  18. ArnHF van der Waals clusters revisited: II. Energetics and HF vibrational frequency shifts from diffusion Monte Carlo calculations on additive and nonadditive potential-energy surfaces for n =1-12

    NASA Astrophysics Data System (ADS)

    Jiang, Hao; Xu, Minzhong; Hutson, Jeremy M.; Bačić, Zlatko

    2005-08-01

    The ground-state energies and HF vibrational frequency shifts of ArnHF clusters have been calculated on the nonadditive potential-energy surfaces (PESs) for n =2-7 and on the pairwise-additive PESs for the clusters with n =1-12, using the diffusion Monte Carlo (DMC) method. For n >3, the calculations have been performed for the lowest-energy isomer and several higher-lying isomers which are the closest in energy. They provide information about the isomer dependence of the HF redshift, and enable direct comparison with the experimental data recently obtained in helium nanodroplets. The agreement between theory and experiment is excellent, in particular, for the nonadditive DMC redshifts. The relative, incremental redshifts are reproduced accurately even at the lower level of theory, i.e., the DMC and quantum five-dimensional (rigid Arn) calculations on the pairwise-additive PESs. The nonadditive interactions make a significant contribution to the frequency shift, on the order of 10%-12%, and have to be included in the PESs in order for the theory to yield accurate magnitude of the HF redshift. The energy gaps between the DMC ground states of the cluster isomers are very different from the energy separation of their respective minima on the PES, due to the considerable variations in the intermolecular zero-point energy of different ArnHF isomers.

  19. Genetics Home Reference: van der Woude syndrome

    MedlinePlus

    ... Moretti-Ferreira D, Richieri-Costa A, Dixon MJ, Murray JC. Mutations in IRF6 cause Van der Woude ... PubMed Central Nopoulos P, Richman L, Andreasen N, Murray JC, Schutte B. Cognitive dysfunction in adults with ...

  20. Ab initio study of the electronic and optical properties of Ag3AuS2 polymorphs

    NASA Astrophysics Data System (ADS)

    Shah, Syed Sarmad Ali; Khan, Afzal; Haidar Khan, Shah; Muhammad, Nisar; Ayaz Khan, Saleem; Gulbahar Ashiq, M.; Murtaza, G.

    2017-08-01

    Natural and synthetic uytenbogaardtite (Ag3AuS2) polymorphs have been studied for their structural, compositional and thermodynamic properties. We investigated their electronic and optical properties for the first time using density functional theory. These calculations are based on the full potential linearized augmented plane wave method using the modified Becke-Johnson potential. Our calculations reveal that Ag3AuS2 is a direct band gap semiconductor exhibiting three crystal phases, cubic, trigonal and triclinic. The calculated band gaps for cubic, trigonal and triclinic phases are 1.15, 2.15 and 1.73 eV, respectively. The band gaps of the Ag3AuS2 polymorphs in the near infrared and visible region highlight the importance of these polymorphs for optoelectronic applications such as resistive switches, low-loss optical fibers, thin-film solar cells and thin-film photovoltaic devices. Furthermore, our calculations show that the electronic and optical properties of Ag3AuS2 are crystal phase dependent.

  1. Establishing the Aus-ROC Australian and New Zealand out-of-hospital cardiac arrest Epistry

    PubMed Central

    Bray, Janet; Smith, Karen; Walker, Tony; Grantham, Hugh; Hein, Cindy; Thorrowgood, Melanie; Smith, Anthony; Smith, Tony; Dicker, Bridget; Swain, Andy; Bailey, Mark; Bosley, Emma; Pemberton, Katherine; Cameron, Peter; Nichol, Graham; Finn, Judith

    2016-01-01

    Introduction Out-of-hospital cardiac arrest (OHCA) is a global health problem with low survival. Regional variation in survival has heightened interest in combining cardiac arrest registries to understand and improve OHCA outcomes. While individual OHCA registries exist in Australian and New Zealand ambulance services, until recently these registries have not been combined. The aim of this protocol paper is to describe the rationale and methods of the Australian Resuscitation Outcomes Consortium (Aus-ROC) OHCA epidemiological registry (Epistry). Methods and analysis The Aus-ROC Epistry is designed as a population-based cohort study. Data collection started in 2014. Six ambulance services in Australia (Ambulance Victoria, SA Ambulance Service, St John Ambulance Western Australia and Queensland Ambulance Service) and New Zealand (St John New Zealand and Wellington Free Ambulance) currently contribute data. All OHCA attended by ambulance, regardless of aetiology or patient age, are included in the Epistry. The catchment population is approximately 19.3 million persons, representing 63% of the Australian population and 100% of the New Zealand population. Data are collected using Utstein-style definitions. Information incorporated into the Epistry includes demographics, arrest features, ambulance response times, treatment and patient outcomes. The primary outcome is ‘survival to hospital discharge’, with ‘return of spontaneous circulation’ as a key secondary outcome. Ethics and dissemination Ethics approval was independently sought by each of the contributing registries. Overarching ethics for the Epistry was provided by Monash University HREC (Approval No. CF12/3938—2012001888). A population-based OHCA registry capturing the majority of Australia and New Zealand will allow risk-adjusted outcomes to be determined, to enable benchmarking across ambulance providers, facilitate the identification of system-wide strategies associated with survival from OHCA, and

  2. Van der Waals Epitaxy of Ultrathin Halide Perovkistes

    NASA Astrophysics Data System (ADS)

    Wang, Yiping; Shi, Yunfeng; Shi, Jian

    We present our understanding, with CH3NH3PbX3 as a model system, on the 2D van der Waals growth and kinetics of 3D parent materials. We show the successful synthesis of ultrathin (sub-10 nm), large scale (a few tens of μm) single crystalline 2D perovskite thin films on layered mica substrate by van der Waals (VDW) epitaxy. Classical nucleation and growth model explaining conventional epitaxy has been modified to interpret the unique 2D results under VDW mechanism. The generalization of our model shows that a 3D crystal with low cohesive energy tends to favor the 2D growth while the one with strong cohesive energy has less kinetic window. With Monte Carlo simulations, we show that the fractal 2D morphology in perovskite precisely manifests the kinetic competition between VDW diffusivity and thermodynamic driving force, a unique phenomenon to VDW growth, suggesting a fundamental limit on the morphology stability of the 2D form of a 3D material. On the other hand, our single crystal thin film growth results and subsequent cryogenic study in the iodide perovskite provide a perfect resource for the exploration of its complex optical and electronic properties and unveiling the origins of its popularity in the energy conversion field.

  3. Effect of van der Waals interactions on the structural and binding properties of GaSe

    SciTech Connect

    Sarkisov, Sergey Y.; Kosobutsky, Alexey V.; Shandakov, Sergey D.

    2015-12-15

    The influence of van der Waals interactions on the lattice parameters, band structure, elastic moduli and binding energy of layered GaSe compound has been studied using projector-augmented wave method within density functional theory. We employed the conventional local/semilocal exchange-correlation functionals and recently developed van der Waals functionals which are able to describe dispersion forces. It is found that application of van der Waals density functionals allows to substantially increase the accuracy of calculations of the lattice constants a and c and interlayer distance in GaSe at ambient conditions and under hydrostatic pressure. The pressure dependences of the a-parameter, Ga–Ga, Ga–Se bond lengths and Ga–Ga–Se bond angle are characterized by a relatively low curvature, while c(p) has a distinct downward bowing due to nonlinear shrinking of the interlayer spacing. From the calculated binding energy curves we deduce the interlayer binding energy of GaSe, which is found to be in the range 0.172–0.197 eV/layer (14.2–16.2 meV/Å{sup 2}). - Highlights: • Effects of van der Waals interactions are analyzed using advanced density functionals. • Calculations with vdW-corrected functionals closely agree with experiment. • Interlayer binding energy of GaSe is estimated to be 14.2–16.2 meV/Å{sup 2}.

  4. Wie wissenschaftlich ist der Evolutionsgedanke?

    NASA Astrophysics Data System (ADS)

    Vollmer, Gerhard

    Darwin war ein besonnener Mann; alles Aufsehen war ihm zuwider. Trotzdem hat er eine Revolution ausgelöst, deren Wirkung nicht auf die Biologie beschränkt blieb. Seine Theorie lässt sich in fünf Teiltheorien zerlegen, die sich durch die Begriffe Artenwandel, Verwandtschaft alles Lebendigen und gemeinsamer Ursprung, Artenaufspaltung und Artenvielfalt, Gradualismus, natürliche Auslese charakterisieren lassen. Dadurch wurden mehrere religiöse und weitere weltanschauliche Überzeugungen in Frage gestellt. Deshalb wird die Evolutionstheorie auch heute noch vielfach kritisiert, ja bekämpft. Die Vorwürfe lassen sich ordnen nach den Kriterien, mit denen wir erfahrungswissenschaftliche Theorien beurteilen. Haltbar ist daran nur, dass es für die Evolutionstheorie zwar beliebig viele Bestätigungen gibt, aber nur wenige Widerlegungsmöglichkeiten. Durch die neuerdings entwickelten und durchgeführten Evolutionsexperimente ist die empirische Situation allerdings deutlich besser geworden. Am (erfahrungs)wissenschaftlichen Charakter der Evolutionstheorie besteht deshalb kein Zweifel.

  5. Modellbasierte interindividuelle Registrierung an der lateralen Schädelbasis

    NASA Astrophysics Data System (ADS)

    Riechmann, M.; Lohnstein, P. U.; Raczkowsky, J.; Klenzner, T.; Schipper, J.; Wörn, H.

    Bei chirurgischen Eingriffen an der lateralen Schädelbasis wird in der zur Zeit gängigen Praxis das Knochengewebe unter optischer Kontrolle großflächig ablativ entfernt, um den Operationssitus freizulegen und konventionell operieren zu können. Prinzipiell soll dabei die Schonung vital und funktional bedeutender Strukturen berücksichtigt werden. Zur weiteren Minimierung der Traumatisierung und zur Erhaltung der strukturellen anatomischen Integrität soll eine alternative endoskopische Operationstechnik entwickelt werden, bei der der Situs durch dünne im Knochen liegende Bohrkanäle erreicht wird. Im Rahmen der Evaluierung der generellen Eignung der geometrischen Ausprägungen der humanen lateralen Schädelbasis wurden Methoden entwickelt, die anhand virtueller Modelle die Zugänglichkeit der anatomischen Zielstrukturen bestimmen können. Ein dabei auftretendes Problem ist die interindividuelle Vergleichbarkeit der Ergebnisse, da aufgrund der anatomischen Variationen eine zuverlässige interindividuelle Registrierung nicht trivial ist. Diese Arbeit beschreibt ein modellbasiertes Verfahren zur automatischen Registrierung mehrerer Felsenbeine zu einander über die prägnante Geometrie der Cochlea.

  6. van der Waals equation of state for a fluid in a nanopore.

    PubMed

    Zarragoicoechea, Guillermo J; Kuz, Víctor A

    2002-02-01

    A generalization of the van der Waals equation of state is presented for a confined fluid in a nanopore. The pressure in the fluid, confined in a narrow pore of infinite length, has tensorial character. From this hypothesis, the Helmholtz free energy is constructed and expressions for the axial and transversal components of the pressure tensor are obtained. The equations predict liquid-vapor equilibria, and a shift of the critical point with respect to that obtained from the van der Waals bulk equation. The results are in good agreement with recent experiments.

  7. Enhanced and switchable nanoscale thermal conduction due to van der Waals interfaces.

    PubMed

    Yang, Juekuan; Yang, Yang; Waltermire, Scott W; Wu, Xiaoxia; Zhang, Haitao; Gutu, Timothy; Jiang, Youfei; Chen, Yunfei; Zinn, Alfred A; Prasher, Ravi; Xu, Terry T; Li, Deyu

    2011-12-11

    Understanding thermal transport in nanostructured materials is important for the development of energy conversion applications and the thermal management of microelectronic and optoelectronic devices. Most nanostructures interact through van der Waals interactions, and these interactions typically lead to a reduction in thermal transport. Here, we show that the thermal conductivity of a bundle of boron nanoribbons can be significantly higher than that of a single free-standing nanoribbon. Moreover, the thermal conductivity of the bundle can be switched between the enhanced values and that of a single nanoribbon by wetting the van der Waals interface between the nanoribbons with various solutions.

  8. Effect of van der Waals interaction on the mode I fracture characteristics of graphene sheet

    NASA Astrophysics Data System (ADS)

    Parashar, Avinash; Mertiny, Pierre

    2013-11-01

    In this paper a study has been performed to investigate the effect of van der Waals interaction forces on the mode I (opening mode) fracture characteristics of a graphene sheet. Finite element based atomistic approach was employed to perform the investigation, where graphene structure was assumed to behave like a space frame structure. Few graphene sheets were modeled in finite element environment with different set of interlayer spacing. Modified virtual crack closure technique (VCCT) was employed to estimate the strain energy release rate (SERR) under mode I of fracture criteria. Significant effect of van der Waals forces was observed on the mode I fracture characteristics of graphene.

  9. Hypoallergenic Der p 1/Der p 2 combination vaccines for immunotherapy of house dust mite allergy.

    PubMed

    Chen, Kuan-Wei; Blatt, Katharina; Thomas, Wayne R; Swoboda, Ines; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

    2012-08-01

    More than 50% of allergic patients have house dust mite (HDM) allergy. Group 1 and 2 allergens are the major HDM allergens. We sought to produce and perform preclinical characterization of a recombinant hypoallergenic combination vaccine for specific immunotherapy of HDM allergy. Synthetic genes coding for 2 hybrid proteins consisting of reassembled Der p 1 and Der p 2 fragments with (recombinant Der p 2 [rDer p 2]/1C) and without (rDer p 2/1S) cysteines were expressed in Escherichia coli and purified to homogeneity by means of affinity chromatography. Protein fold was determined by using circular dichroism analysis, allergenic activity was determined by testing IgE reactivity and using basophil activation assays, and the presence of T-cell epitopes was determined based on lymphoproliferation in allergic patients. Mice and rabbits were immunized to study the molecules' ability to induce an allergic response and whether they induce allergen-specific IgG capable of inhibiting allergic patients' IgE binding to the allergens, respectively. rDer p 2/1C and rDer p 2/1S were expressed in large amounts in E coli as soluble and folded proteins. Because of the lack of disulfide bonds, rDer p 2/1S did not form aggregates and was obtained as a monomeric protein, whereas rDer p 2/1C did form aggregates. Both hypoallergens lacked relevant IgE reactivity and had reduced ability to induce allergic inflammation and allergic responses but induced similar T-cell proliferation as the wild-type allergens. Immunization with the hypoallergens (rDer p 2/1S > rDer p 2/1C) induced IgG antibodies in rabbits that inhibited the IgE reactivity of patients with HDM allergy to Der p 1 and Der p 2. The preclinical characterization indicates that particularly rDer p 2/1S can be used as a safe hypoallergenic molecule for both tolerance and vaccination approaches to treat HDM allergy. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  10. Detection of inhaled Der p 1.

    PubMed

    Poulos, L M; O'Meara, T J; Sporik, R; Tovey, E R

    1999-09-01

    Measurement of personal exposure to Der p 1 aeroallergen has previously been limited by the low quantity of material collected by sampling systems and the assay sensitivity. This has meant that exposure could only be detected if long sampling periods were used or reservoir dust was artificially disturbed. We have developed a sampling method to sample true personal exposure and combined it with a novel method which is sensitive enough to measure allergen exposure over shorter time frames. To describe normal domestic exposure to dust mite allergen during a range of activities in houses in Sydney, Australia. Inhaled particles containing mite allergen Der p 1 were collected using a nasal air sampler which impacts particles (> approximately 5 microm) onto a protein-binding membrane coated with a thin, porous, adhesive film. The allergen is bound to the membrane in the immediate vicinity of the particle and detected by immunostaining with monoclonal antibodies specific for Der p 1. In addition, samples were collected using a standard Institute of Occupational Medicine (IOM) personal air sampler and the amount of eluted Der p 1 was assayed by ELISA. The median number (range) of inhaled particles containing Der p 1 collected in each 10-min sampling period was: dust raising 5 (2-10); lying in bed, 0 (0-2); sitting on the bed, 1 (0-2); walking around the bedroom, 0 (0-2). This represented 0-5.1% of all particles captured. The Der p 1 concentration of floor and bed dust was 19.4 and 55.1 microg/g, respectively. The standard IOM personal sampler and ELISA were unable to detect Der p 1 for any of the activities performed. We were able to count individual allergen-carrying particles inhaled over short time periods, during different domestic exposure situations. This will offer new insight into several aspects of personal allergen exposure.

  11. Slit-jet near-infrared spectroscopy and internal rotor dynamics of the ArH2O van der Waals complex: An angular potential-energy surface for internal H2O rotation

    NASA Astrophysics Data System (ADS)

    Lascola, Robert; Nesbitt, David J.

    1991-12-01

    Near-infrared vibration-rotation spectra of jet-cooled Ar-H2O complexes are detected for the first time via direct absorption of tunable difference frequency infrared radiation in a slit supersonic expansion source. Transitions from both the lowest para and ortho complexes are observed which correlate to 000 and 101 rotational levels of free H2O, respectively, and permit spectroscopic characterization of the complex in both the ground (ν3=0) and asymmetric stretch excited (ν3=1) levels. From hot bands involving excited internal rotor states correlating with the 101 H2O rotational level, we determine the Σe(101)-Πf(101) energy splitting to be 11.3333(3) cm-1 (J=1). In conjunction with far-infrared measurements of the Σ(110)-Π(101) and Π(110)-Σ(101) energy splittings, this information permits determination of a two-dimensional (2D) angular potential-energy surface of the complex as a function of the H2O orientation. The barriers to internal rotation of an ArH2O differ for in-plane (19 cm-1) and out-of-plane (33 cm-1 ) rotation of the H2O subunit. However, both barriers are only slightly higher than the ground-state energies and, hence, the behavior of H2O in the complex is that of a nearly free rotor. Agreement with recent ab initio calculations by Chalasinski et al. [J. Chem. Phys. 94, 2807 (1991)], as well as with 3D fits solely to far-infrared data by Cohen and Saykally [J. Chem. Phys. 94, 7991 (1991)], is remarkably good. Predictions based on this angular potential-energy surface are made for the internal rotor states of ArHDO and ArD2O and compared with recent far-infrared measurements by Suzuki et al. [J. Phys. Chem. 94, 824 (1991)].

  12. Dynamical importance of van der Waals saddle and excited potential surface in C((1)D)+D2 complex-forming reaction.

    PubMed

    Shen, Zhitao; Ma, Haitao; Zhang, Chunfang; Fu, Mingkai; Wu, Yanan; Bian, Wensheng; Cao, Jianwei

    2017-01-17

    Encouraged by recent advances in revealing significant effects of van der Waals wells on reaction dynamics, many people assume that van der Waals wells are inevitable in chemical reactions. Here we find that the weak long-range forces cause van der Waals saddles in the prototypical C((1)D)+D2 complex-forming reaction that have very different dynamical effects from van der Waals wells at low collision energies. Accurate quantum dynamics calculations on our highly accurate ab initio potential energy surfaces with van der Waals saddles yield cross-sections in close agreement with crossed-beam experiments, whereas the same calculations on an earlier surface with van der Waals wells produce much smaller cross-sections at low energies. Further trajectory calculations reveal that the van der Waals saddle leads to a torsion then sideways insertion reaction mechanism, whereas the well suppresses reactivity. Quantum diffraction oscillations and sharp resonances are also predicted based on our ground- and excited-state potential energy surfaces.

  13. Dynamical importance of van der Waals saddle and excited potential surface in C(1D)+D2 complex-forming reaction

    NASA Astrophysics Data System (ADS)

    Shen, Zhitao; Ma, Haitao; Zhang, Chunfang; Fu, Mingkai; Wu, Yanan; Bian, Wensheng; Cao, Jianwei

    2017-01-01

    Encouraged by recent advances in revealing significant effects of van der Waals wells on reaction dynamics, many people assume that van der Waals wells are inevitable in chemical reactions. Here we find that the weak long-range forces cause van der Waals saddles in the prototypical C(1D)+D2 complex-forming reaction that have very different dynamical effects from van der Waals wells at low collision energies. Accurate quantum dynamics calculations on our highly accurate ab initio potential energy surfaces with van der Waals saddles yield cross-sections in close agreement with crossed-beam experiments, whereas the same calculations on an earlier surface with van der Waals wells produce much smaller cross-sections at low energies. Further trajectory calculations reveal that the van der Waals saddle leads to a torsion then sideways insertion reaction mechanism, whereas the well suppresses reactivity. Quantum diffraction oscillations and sharp resonances are also predicted based on our ground- and excited-state potential energy surfaces.

  14. Dynamical importance of van der Waals saddle and excited potential surface in C(1D)+D2 complex-forming reaction

    PubMed Central

    Shen, Zhitao; Ma, Haitao; Zhang, Chunfang; Fu, Mingkai; Wu, Yanan; Bian, Wensheng; Cao, Jianwei

    2017-01-01

    Encouraged by recent advances in revealing significant effects of van der Waals wells on reaction dynamics, many people assume that van der Waals wells are inevitable in chemical reactions. Here we find that the weak long-range forces cause van der Waals saddles in the prototypical C(1D)+D2 complex-forming reaction that have very different dynamical effects from van der Waals wells at low collision energies. Accurate quantum dynamics calculations on our highly accurate ab initio potential energy surfaces with van der Waals saddles yield cross-sections in close agreement with crossed-beam experiments, whereas the same calculations on an earlier surface with van der Waals wells produce much smaller cross-sections at low energies. Further trajectory calculations reveal that the van der Waals saddle leads to a torsion then sideways insertion reaction mechanism, whereas the well suppresses reactivity. Quantum diffraction oscillations and sharp resonances are also predicted based on our ground- and excited-state potential energy surfaces. PMID:28094253

  15. Interoperability - a Key Element for the Grid and DER of the Future

    SciTech Connect

    Hamilton, S.; Gunther, E.; Drummond, R.; Widergren, Steven E.

    2006-05-21

    The information exchange and coordinated control of distributed energy resources (DER) for many different purposes to the benefit of various parties represents a complex problem. The large number of DER devices means that the information exchange approaches, must be scalable, must accommodate a changing variety of communications technologies over time, and lend themselves to safe and reliable distributed decision making schemes. Mainstream information technology (IT) techniques will drive these approaches, but what can be done to facilitate the integration of the vast number of these resources into the larger system so they can interoperate more easily? Establishing a common vision of interoperability principles for the integration of DER in the power system can help address this question.

  16. van der Waals forces influencing adhesion of cells

    PubMed Central

    Kendall, K.; Roberts, A. D.

    2015-01-01

    Adhesion molecules, often thought to be acting by a ‘lock and key’ mechanism, have been thought to control the adhesion of cells. While there is no doubt that a coating of adhesion molecules such as fibronectin on a surface affects cell adhesion, this paper aims to show that such surface contamination is only one factor in the equation. Starting from the baseline idea that van der Waals force is a ubiquitous attraction between all molecules, and thereby must contribute to cell adhesion, it is clear that effects from geometry, elasticity and surface molecules must all add on to the basic cell attractive force. These effects of geometry, elasticity and surface molecules are analysed. The adhesion force measured between macroscopic polymer spheres was found to be strongest when the surfaces were absolutely smooth and clean, with no projecting protruberances. Values of the measured surface energy were then about 35 mJ m−2, as expected for van der Waals attractions between the non-polar molecules. Surface projections such as abrasion roughness or dust reduced the molecular adhesion substantially. Water cut the measured surface energy to 3.4 mJ m−2. Surface active molecules lowered the adhesion still further to less than 0.3 mJ m−2. These observations do not support the lock and key concept. PMID:25533101

  17. Binding and Diffusion of Lithium in Graphite: Quantum Monte Carlo Benchmarks and Validation of van der Waals Density Functional Methods.

    PubMed

    Ganesh, P; Kim, Jeongnim; Park, Changwon; Yoon, Mina; Reboredo, Fernando A; Kent, Paul R C

    2014-12-09

    Highly accurate diffusion quantum Monte Carlo (QMC) studies of the adsorption and diffusion of atomic lithium in AA-stacked graphite are compared with van der Waals-including density functional theory (DFT) calculations. Predicted QMC lattice constants for pure AA graphite agree with experiment. Pure AA-stacked graphite is shown to challenge many van der Waals methods even when they are accurate for conventional AB graphite. Highest overall DFT accuracy, considering pure AA-stacked graphite as well as lithium binding and diffusion, is obtained by the self-consistent van der Waals functional vdW-DF2, although errors in binding energies remain. Empirical approaches based on point charges such as DFT-D are inaccurate unless the local charge transfer is assessed. The results demonstrate that the lithium-carbon system requires a simultaneous highly accurate description of both charge transfer and van der Waals interactions, favoring self-consistent approaches.

  18. Binding and Diffusion of Lithium in Graphite: Quantum Monte Carlo Benchmarks and Validation of van der Waals Density Functional Methods

    SciTech Connect

    Ganesh, P.; Kim, Jeongnim; Park, Changwon; Yoon, Mina; Reboredo, Fernando A.; Kent, Paul R. C.

    2014-11-03

    In highly accurate diffusion quantum Monte Carlo (QMC) studies of the adsorption and diffusion of atomic lithium in AA-stacked graphite are compared with van der Waals-including density functional theory (DFT) calculations. Predicted QMC lattice constants for pure AA graphite agree with experiment. Pure AA-stacked graphite is shown to challenge many van der Waals methods even when they are accurate for conventional AB graphite. Moreover, the highest overall DFT accuracy, considering pure AA-stacked graphite as well as lithium binding and diffusion, is obtained by the self-consistent van der Waals functional vdW-DF2, although errors in binding energies remain. Empirical approaches based on point charges such as DFT-D are inaccurate unless the local charge transfer is assessed. Our results demonstrate that the lithium carbon system requires a simultaneous highly accurate description of both charge transfer and van der Waals interactions, favoring self-consistent approaches.

  19. Energy.

    ERIC Educational Resources Information Center

    Shanebrook, J. Richard

    This document describes a course designed to acquaint students with the many societal and technological problems facing the United States and the world due to the increasing demand for energy. The course begins with a writing assignment that involves readings on the environmental philosophy of Native Americans and the Chernobyl catastrophe.…

  20. Integrable extended van der Waals model

    NASA Astrophysics Data System (ADS)

    Giglio, Francesco; Landolfi, Giulio; Moro, Antonio

    2016-10-01

    Inspired by the recent developments in the study of the thermodynamics of van der Waals fluids via the theory of nonlinear conservation laws and the description of phase transitions in terms of classical (dissipative) shock waves, we propose a novel approach to the construction of multi-parameter generalisations of the van der Waals model. The theory of integrable nonlinear conservation laws still represents the inspiring framework. Starting from a macroscopic approach, a four parameter family of integrable extended van der Waals models is indeed constructed in such a way that the equation of state is a solution to an integrable nonlinear conservation law linearisable by a Cole-Hopf transformation. This family is further specified by the request that, in regime of high temperature, far from the critical region, the extended model reproduces asymptotically the standard van der Waals equation of state. We provide a detailed comparison of our extended model with two notable empirical models such as Peng-Robinson and Soave's modification of the Redlich-Kwong equations of state. We show that our extended van der Waals equation of state is compatible with both empirical models for a suitable choice of the free parameters and can be viewed as a master interpolating equation. The present approach also suggests that further generalisations can be obtained by including the class of dispersive and viscous-dispersive nonlinear conservation laws and could lead to a new type of thermodynamic phase transitions associated to nonclassical and dispersive shock waves.

  1. Establishing the Aus-ROC Australian and New Zealand out-of-hospital cardiac arrest Epistry.

    PubMed

    Beck, Ben; Bray, Janet; Smith, Karen; Walker, Tony; Grantham, Hugh; Hein, Cindy; Thorrowgood, Melanie; Smith, Anthony; Smith, Tony; Dicker, Bridget; Swain, Andy; Bailey, Mark; Bosley, Emma; Pemberton, Katherine; Cameron, Peter; Nichol, Graham; Finn, Judith

    2016-04-05

    Out-of-hospital cardiac arrest (OHCA) is a global health problem with low survival. Regional variation in survival has heightened interest in combining cardiac arrest registries to understand and improve OHCA outcomes. While individual OHCA registries exist in Australian and New Zealand ambulance services, until recently these registries have not been combined. The aim of this protocol paper is to describe the rationale and methods of the Australian Resuscitation Outcomes Consortium (Aus-ROC) OHCA epidemiological registry (Epistry). The Aus-ROC Epistry is designed as a population-based cohort study. Data collection started in 2014. Six ambulance services in Australia (Ambulance Victoria, SA Ambulance Service, St John Ambulance Western Australia and Queensland Ambulance Service) and New Zealand (St John New Zealand and Wellington Free Ambulance) currently contribute data. All OHCA attended by ambulance, regardless of aetiology or patient age, are included in the Epistry. The catchment population is approximately 19.3 million persons, representing 63% of the Australian population and 100% of the New Zealand population. Data are collected using Utstein-style definitions. Information incorporated into the Epistry includes demographics, arrest features, ambulance response times, treatment and patient outcomes. The primary outcome is 'survival to hospital discharge', with 'return of spontaneous circulation' as a key secondary outcome. Ethics approval was independently sought by each of the contributing registries. Overarching ethics for the Epistry was provided by Monash University HREC (Approval No. CF12/3938-2012001888). A population-based OHCA registry capturing the majority of Australia and New Zealand will allow risk-adjusted outcomes to be determined, to enable benchmarking across ambulance providers, facilitate the identification of system-wide strategies associated with survival from OHCA, and allow monitoring of temporal trends in process and outcomes to improve

  2. EXPERIMENTAL AND THEORETICAL STUDIES OF THE CN-AR VAN DER WAALS COMPLEX

    USDA-ARS?s Scientific Manuscript database

    The CN-Ar van der Waals complex has been observed using B2E+-X2E+ and A2II-X2E+ electronic transitions. The spectra yielded a dissociation energy of D0"=109+2 cm1 and a zero point rational constant of B0"=0.067+0.005 cm-1 for CN(x)-Ar. The dissociation energy for Cn(A)-Ar was found to be D0"=132+2...

  3. Einbeziehung des Elternhauses durch Lehrer: Art, Ausmass und Bedingungen der Elternpartizipation aus der Sicht von Gymnasiallehrern (The Inclusion of the Parental Home by Teachers: Mode, Extent, and Conditions of Parental Participation from the Perspective of High School Teachers).

    ERIC Educational Resources Information Center

    Wild, Elke

    2003-01-01

    Examines a survey among high school teachers that focuses on their attitudes, convictions, and assessment of external factors and conditions that effect the goal of parent cooperation in homework supervision. Concludes teachers are open minded. Offers clues to optimizing the cooperation between parents and teachers. (CAJ)

  4. "Weil Man da Uber Seine Probleme Reden Kann . . ." Partielle Geschlechtertrennung aus der Sicht der Schulerinnen und Schuler ("Because There, You can Talk about Your Problems . . ." Partial Separation by Gender from the Perspective of Male and Female Students).

    ERIC Educational Resources Information Center

    Biskup, Claudia; Pfister, Gertrud; Robke, Cathrin

    1998-01-01

    Examines the results of interviews with elementary school children that gauged the attitudes towards and reasons for a partial separation by gender. Proposes an occassional separation of girls and boys for special pedogogical intervention. Discusses the findings. (CMK)

  5. "Weil Man da Uber Seine Probleme Reden Kann . . ." Partielle Geschlechtertrennung aus der Sicht der Schulerinnen und Schuler ("Because There, You can Talk about Your Problems . . ." Partial Separation by Gender from the Perspective of Male and Female Students).

    ERIC Educational Resources Information Center

    Biskup, Claudia; Pfister, Gertrud; Robke, Cathrin

    1998-01-01

    Examines the results of interviews with elementary school children that gauged the attitudes towards and reasons for a partial separation by gender. Proposes an occassional separation of girls and boys for special pedogogical intervention. Discusses the findings. (CMK)

  6. Bildung in der Struktur Sozio-oekonomisher Entwicklung: Eine Analyse von Laengsschnittsdaten aus Afrika suedlich der Sahara (Education in the Structure of Socioeconomic Development: An Analysis of Longitudinal Data from Sub-Saharan Africa).

    ERIC Educational Resources Information Center

    Bergmann, Herbert

    1991-01-01

    Examines development indicators from 1960 to 1984 for 38 sub-Saharan African countries to determine whether education is an independent factor in development. Concludes that development indicators are determined by factors including basic education; urbanization; pupil-teacher ratio; standard of living; economic growth; service sector; food…

  7. Molecular Interactions in Particular Van der Waals Nanoclusters

    NASA Astrophysics Data System (ADS)

    Jungclas, Hartmut; Komarov, Viacheslav V.; Popova, Anna M.; Schmidt, Lothar

    2017-01-01

    A method is presented to analyse the interaction energies in a nanocluster, which is consisting of three neutral molecules bound by non-covalent long range Van der Waals forces. One of the molecules (M0) in the nanocluster has a permanent dipole moment, whereas the two other molecules (M1 and M2) are non-polar. Analytical expressions are obtained for the numerical calculation of the dispersion and induction energies of the molecules in the considered nanocluster. The repulsive forces at short intermolecular distances are taken into account by introduction of damping functions. Dispersion and induction energies are calculated for a nanocluster with a definite geometry, in which the polar molecule M0 is a linear hydrocarbon molecule C5H10 and M1 and M2 are pyrene molecules. The calculations are done for fixed distances between the two pyrene molecules. The results show that the induction energies in the considered three-molecular nanocluster are comparable with the dispersion energies. Furthermore, the sum of induction energies in the substructure (M0, M1) of the considered nanocluster is much higher than the sum of induction energies in a two-molecular nanocluster with similar molecules (M0, M1) because of the absence of an electrostatic field in the latter case. This effect can be explained by the essential intermolecular induction in the three-molecular nanocluster.

  8. Efficient thermoelectric van der Pauw measurements

    NASA Astrophysics Data System (ADS)

    de Boor, Johannes; Schmidt, Volker

    2011-07-01

    The development of powerful thermoelectric materials requires fast and simple characterization techniques. We combine three measurements to obtain a complete thermoelectric characterization. The electrical conductivity is measured by the van der Pauw method, while ZT is determined directly by means of a Harman measurement. Finally, exploiting the analogy between electrical and thermal physics, a thermal van der Pauw measurement is performed and the sample Seebeck coefficient and thermal conductivity can be determined. No temperature differences need to be measured; all quantities can be deduced from voltage measurements concurrently on the same sample which allows for quick and convenient material screening.

  9. van der Waals radii of noble gases.

    PubMed

    Vogt, Jürgen; Alvarez, Santiago

    2014-09-02

    Consistent van der Waals radii are deduced for Ne-Xe, based on the noble gas···oxygen intermolecular distances found in gas phase structures. The set of radii proposed is shown to provide van der Waals distances for a wide variety of noble gas···element atom pairs that represent properly the distribution of distances both in the gas phase and in the solid state. Moreover, these radii show a smooth periodic trend down the group which is parallel to that shown by the halogens.

  10. A four-dimensional potential energy surface and predicted infrared spectra for the Ne-D2O van der Waals complex in the ν2 bending region of D2O molecule

    NASA Astrophysics Data System (ADS)

    He, Shanshan; Chen, Dong; Li, Ya; Feng, Eryin; Huang, Wuying

    2016-11-01

    In this paper, a four-dimensional potential energy surface (PES) for the Ne-D2O complex is constructed theoretically. The calculations are carried out at CCSD(T) level with large basis sets augmented with mid-bond functions. The PES includes explicit dependence on the ν2 symmetric bending coordinate Q2 of the D2O molecule. Two vibrationally averaged potentials in the ground and first excited bending states are obtained respectively. Using these two potentials we calculate the bound states of the complexes. The theoretical rovibrational transition frequencies for three bands: П(111,ν2 = 1)←Σ000, Σ(111,ν2 = 1)←Σ000 and n = 1, Σ(000,ν2 = 1)←Σ000 are predicted and generally in good agreement with the experimental observed values.

  11. Central obesity as a precursor to the metabolic syndrome in the AusDiab study and Mauritius.

    PubMed

    Cameron, Adrian J; Boyko, Edward J; Sicree, Richard A; Zimmet, Paul Z; Söderberg, Stefan; Alberti, K George M M; Tuomilehto, Jaakko; Chitson, Pierrot; Shaw, Jonathan E

    2008-12-01

    Evidence from epidemiologic studies that central obesity precedes future metabolic change and does not occur concurrently with the appearance of the blood pressure, glucose, and lipid abnormalities that characterize the metabolic syndrome (MetS) has been lacking. Longitudinal surveys were conducted in Mauritius in 1987, 1992, and 1998, and in Australia in 2000 and 2005 (AusDiab). This analysis included men and women (aged > or = 25 years) in three cohorts: AusDiab 2000-2005 (n = 5,039), Mauritius 1987-1992 (n = 2,849), and Mauritius 1987-1998 (n = 1,999). MetS components included waist circumference, systolic blood pressure, fasting and 2-h postload plasma glucose, high-density lipoprotein (HDL) cholesterol, triglycerides, and homeostasis model assessment of insulin sensitivity (HOMA-S) (representing insulin sensitivity). Linear regression was used to determine which baseline components predicted deterioration in other MetS components over 5 years in AusDiab and 5 and 11 years in Mauritius, adjusted for age, sex, and ethnic group. Baseline waist circumference predicted deterioration (P < 0.01) in four of the other six MetS variables tested in AusDiab, five of six in Mauritius 1987-1992, and four of six in Mauritius 1987-1998. In contrast, an increase in waist circumference between baseline and follow-up was only predicted by insulin sensitivity (HOMA-S) at baseline, and only in one of the three cohorts. These results suggest that central obesity plays a central role in the development of the MetS and appears to precede the appearance of the other MetS components.

  12. Smart Microgrid Energy Management Controls for Improved Energy Efficiency and Renewables Integration at DoD Installations

    DTIC Science & Technology

    2013-05-01

    excessive distribution losses. Microgrids are envisioned as local power networks that utilize DER and manage the local energy supply and demand. While...certified network communications) hardware and software tailored for the Twentynine Palms operation. GE can specify the technology transfer method...excessive distribution losses. Microgrids are envisioned as local power networks that utilize distributed energy resources (DER) and manage the local

  13. Secure Automated Microgrid Energy System

    DTIC Science & Technology

    2016-12-01

    EW-201340) Secure Automated Microgrid Energy System December 2016 This document has been cleared for public release; Distribution Statement A...Operator COTS Commercial-Off-The-Shelf Software DCS Distributed Control System DER Distributed Energy Resources DIACAP Defense Information...Assurance Certification and Accreditation Process DoD Department of Defense DoDI Department of Defense Instruction DOE Department of Energy

  14. Numerische Berechnung von Wirbelstromproblemen mit der Cell-Methode

    NASA Astrophysics Data System (ADS)

    Frenner, K.; Rucker, W. M.

    2006-09-01

    In dieser Arbeit wird die Cell-Methode auf die quasistatischen Maxwellgleichungen angewendet. Dabei werden für die notwendige Transformation vom Primärgitter auf das duale Gitter reziproke Basisvektoren verwendet. Anhand der Felddiffusion der magnetischen Induktion in einen zylindrischen Leiter werden Ergebnisse der Cell-Methode mit einer analytischen Vergleichsrechnung präsentiert.

  15. Using NOAA/AVHRR based remote sensing data and PCR method for estimation of Aus rice yield in Bangladesh

    NASA Astrophysics Data System (ADS)

    Nizamuddin, Mohammad; Akhand, Kawsar; Roytman, Leonid; Kogan, Felix; Goldberg, Mitch

    2015-06-01

    Rice is a dominant food crop of Bangladesh accounting about 75 percent of agricultural land use for rice cultivation and currently Bangladesh is the world's fourth largest rice producing country. Rice provides about two-third of total calorie supply and about one-half of the agricultural GDP and one-sixth of the national income in Bangladesh. Aus is one of the main rice varieties in Bangladesh. Crop production, especially rice, the main food staple, is the most susceptible to climate change and variability. Any change in climate will, thus, increase uncertainty regarding rice production as climate is major cause year-to-year variability in rice productivity. This paper shows the application of remote sensing data for estimating Aus rice yield in Bangladesh using official statistics of rice yield with real time acquired satellite data from Advanced Very High Resolution Radiometer (AVHRR) sensor and Principal Component Regression (PCR) method was used to construct a model. The simulated result was compared with official agricultural statistics showing that the error of estimation of Aus rice yield was less than 10%. Remote sensing, therefore, is a valuable tool for estimating crop yields well in advance of harvest, and at a low cost.

  16. First principles calculations of solid-state thermionic transport in layered van der Waals heterostructures.

    PubMed

    Wang, Xiaoming; Zebarjadi, Mona; Esfarjani, Keivan

    2016-08-21

    This work aims at understanding solid-state energy conversion and transport in layered (van der Waals) heterostructures in contact with metallic electrodes via a first-principles approach. As an illustration, a graphene/phosphorene/graphene heterostructure in contact with gold electrodes is studied by using density functional theory (DFT)-based first principles calculations combined with real space Green's function (GF) formalism. We show that for a monolayer phosphorene, quantum tunneling dominates the transport. By adding more phosphorene layers, one can switch from tunneling-dominated transport to thermionic-dominated transport, resulting in transporting more heat per charge carrier, thus, enhancing the cooling coefficient of performance. The use of layered van der Waals heterostructures has two advantages: (a) thermionic transport barriers can be tuned by changing the number of layers, and (b) thermal conductance across these non-covalent structures is very weak. The phonon thermal conductance of the present van der Waals heterostructure is found to be 4.1 MW m(-2) K(-1) which is one order of magnitude lower than the lowest value for that of covalently-bonded interfaces. The thermionic coefficient of performance for the proposed device is 18.5 at 600 K corresponding to an equivalent ZT of 0.13, which is significant for nanoscale devices. This study shows that layered van der Waals structures have great potential to be used as solid-state energy-conversion devices.

  17. Dynamical screening of the van der Waals interaction between graphene layers.

    PubMed

    Dappe, Y J; Bolcatto, P G; Ortega, J; Flores, F

    2012-10-24

    The interaction between graphene layers is analyzed combining local orbital DFT and second order perturbation theory. For this purpose we use the linear combination of atomic orbitals-orbital occupancy (LCAO-OO) formalism, that allows us to separate the interaction energy as the sum of a weak chemical interaction between graphene layers plus the van der Waals interaction (Dappe et al 2006 Phys. Rev. B 74 205434). In this work, the weak chemical interaction is calculated by means of corrected-LDA calculations using an atomic-like sp(3)d(5) basis set. The van der Waals interaction is calculated by means of second order perturbation theory using an atom-atom interaction approximation and the atomic-like-orbital occupancies. We also analyze the effect of dynamical screening in the van der Waals interaction using a simple model. We find that this dynamical screening reduces by 40% the van der Waals interaction. Taking this effect into account, we obtain a graphene-graphene interaction energy of 70 ± 5 meV/atom in reasonable agreement with the experimental evidence.

  18. Role of the van der Waals interaction in atom-diatom reaction dynamics at low temperatures

    NASA Astrophysics Data System (ADS)

    Weck, Philippe F.; Balakrishnan, Naduvalath; Brandao, Joao; Rosa, Carla; Wang, Wenli

    2006-03-01

    Quantum-mechanical scattering calculations are reported for the O(^3P)+H2 collision at energies close to the reaction threshold with emphasis on the sensitivity of the reaction dynamics to the van der Waals interaction. The dynamics has been investigated using the lowest ^3 A'' GLDP potential energy surface developed by Rogers et al. [J. Phys. Chem. A 104, 2308 (2000)] and its recent BMS1 and BMS2 extensions by Brandão et al. [J. Chem. Phys. 121, 8861 (2004)] which explicitly include the van der Waals interaction. Quasiclassical trajectory calculations on all three potential energy surfaces are also reported to explore the validity of this method near the reaction threshold and to assess the importance of quantum effects at low temperatures.

  19. Structure, Energy, and Vibrational Frequencies of Oxygen Allotropes On (n ≤ 6) in the Covalently Bound and van der Waals Forms: Ab Initio Study at the CCSD(T) Level.

    PubMed

    Gadzhiev, Oleg B; Ignatov, Stanislav K; Kulikov, Mikhail Yu; Feigin, Alexander M; Razuvaev, Alexey G; Sennikov, Peter G; Schrems, Otto

    2013-01-08

    Recent experiments on the UV and electron beam irradiation of solid O2 reveals a series of IR features near the valence antisymmetric vibration band of O3 which are frequently interpreted as the formation of unusual On allotropes in the forms of weak complexes or covalently bound molecules. In order to elucidate the question of the nature of the irradiation products, the structure, relative energies, and vibrational frequencies of various forms of On (n = 1-6) in the singlet, triplet, and, in some cases, quintet states were studied using the CCSD(T) method up to the CCSD(T,full)/cc-pCVTZ and CCSD(T,FC)/aug-cc-pVTZ levels. The results of calculations demonstrate the existence of stable highly symmetric structures O4 (D3h), O4 (D2d), and O6 (D3d) as well as the intermolecular complexes O2·O2, O2·O3, and O3·O3 in different conformations. The calculations show that the local minimum corresponding to the O3···O complex is quite shallow and cannot explain the ν3 band features close to 1040 cm(-1), as was proposed previously. For the ozone dimer, a new conformer was found which is more stable than the structure known to date. The effect of the ozone dimer on the registered IR spectra is discussed.

  20. Die aerobe Glykolyse der Tumorzelle

    NASA Astrophysics Data System (ADS)

    Schneider, Friedhelm

    1981-01-01

    A high aerobic glycolysis (aerobic lactate production) is the most significant feature of the energy metabolism of rapidly growing tumor cells. Several mechanisms, which may be different in different cell lines, seem to be involved in this characteristic of energy metabolism of the tumor cell. Changes in the cell membrane leading to increased uptake and utilization of glucose, a high level of fetal types of isoenzymes, a decreased number of mitochondria and a reduced capacity to metabolize pyruvate are some factors which must be taken into consideration. It is not possible to favour one of them at the present time.

  1. The Forced van der Pol Equation

    ERIC Educational Resources Information Center

    Fay, Temple H.

    2009-01-01

    We report on a study of the forced van der Pol equation x + [epsilon](x[superscript 2] - 1)x + x = F cos[omega]t, by solving numerically the differential equation for a variety of values of the parameters [epsilon], F and [omega]. In doing so, many striking and interesting trajectories can be discovered and phenomena such as frequency entrainment,…

  2. Distributed Energy Resources Market Diffusion Model

    SciTech Connect

    Maribu, Karl Magnus; Firestone, Ryan; Marnay, Chris; Siddiqui,Afzal S.

    2006-06-16

    Distributed generation (DG) technologies, such as gas-fired reciprocating engines and microturbines, have been found to be economically beneficial in meeting commercial-sector electrical, heating, and cooling loads. Even though the electric-only efficiency of DG is lower than that offered by traditional central stations, combined heat and power (CHP) applications using recovered heat can make the overall system energy efficiency of distributed energy resources (DER) greater. From a policy perspective, however, it would be useful to have good estimates of penetration rates of DER under various economic and regulatory scenarios. In order to examine the extent to which DER systems may be adopted at a national level, we model the diffusion of DER in the US commercial building sector under different technical research and technology outreach scenarios. In this context, technology market diffusion is assumed to depend on the system's economic attractiveness and the developer's knowledge about the technology. The latter can be spread both by word-of-mouth and by public outreach programs. To account for regional differences in energy markets and climates, as well as the economic potential for different building types, optimal DER systems are found for several building types and regions. Technology diffusion is then predicted via two scenarios: a baseline scenario and a program scenario, in which more research improves DER performance and stronger technology outreach programs increase DER knowledge. The results depict a large and diverse market where both optimal installed capacity and profitability vary significantly across regions and building types. According to the technology diffusion model, the West region will take the lead in DER installations mainly due to high electricity prices, followed by a later adoption in the Northeast and Midwest regions. Since the DER market is in an early stage, both technology research and outreach programs have the potential to increase

  3. Gerbstoffe aus Potentilla officinalis wirken entzündungshemmend im UV-Erythem-Test und bei Anwendung auf atopischer Haut.

    PubMed

    Hoffmann, Julia; Wölfle, Ute; Schempp, Christoph M; Casetti, Federica

    2016-09-01

    Das Rhizom von Potentilla officinalis (PO) ist reich an Gerbstoffen und wird traditionell zur äußerlichen Behandlung von Entzündungen der Haut und der Schleimhäute verwendet. Ziel der vorliegenden Arbeit war die Bestätigung der antiinflammatorischen Eigenschaften von PO mittels eines UV-Erythem-Tests und einer klinischen Anwendungsstudie bei atopischer Haut. Die antiinflammatorische Wirkung eines PO-Extrakts (standardisiert auf 2 % Trockensubstanz) wurde in einer prospektiven, randomisierten, placebokontrollierten Doppelblindstudie mit 40 gesunden Erwachsenen im UV-Erythem-Test im Vergleich zu 1 % Hydrocortisonacetat untersucht. Im Rahmen einer prospektiven nicht kontrollierten Studie wurde die Wirkung und Verträglichkeit der 2 % PO-Creme an zwölf Erwachsenen und zwölf Kindern mit atopischer Haut nach Anwendung über zwei Wochen in einem definierten Testareal anhand eines Teil-SCORAD untersucht. Zusätzlich wurde die Beeinflussung der Hautrötung im Testareal photometrisch gemessen. Im UV-Erythem-Test zeigte die PO-Creme eine signifikante Reduktion des Erythemindex im Vergleich zum Vehikel. Die antiinflammatorische Wirkung des Verums entsprach der der 1 % Hydrocortisonacetat-Creme. Die klinische Studie bei Atopikern zeigte eine signifikante Abnahme des Teil-SCORAD und des Erythems im Testareal. Es wurden keine Unverträglichkeitsreaktionen beobachtet. PO als 2%ige Zubereitung besitzt entzündungshemmende Eigenschaften und ist wirksam und gut verträglich auf atopischer Haut. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  4. Optimal planning and design of a renewable energy based supply system for microgrids

    DOE PAGES

    Hafez, Omar; Bhattacharya, Kankar

    2012-03-03

    This paper presents a technique for optimal planning and design of hybrid renewable energy systems for microgrid applications. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is used to determine the optimal size and type of distributed energy resources (DERs) and their operating schedules for a sample utility distribution system. Using the DER-CAM results, an evaluation is performed to evaluate the electrical performance of the distribution circuit if the DERs selected by the DER-CAM optimization analyses are incorporated. Results of analyses regarding the economic benefits of utilizing the optimal locations identified for the selected DER within the system are alsomore » presented. The actual Brookhaven National Laboratory (BNL) campus electrical network is used as an example to show the effectiveness of this approach. The results show that these technical and economic analyses of hybrid renewable energy systems are essential for the efficient utilization of renewable energy resources for microgird applications.« less

  5. Optimal planning and design of a renewable energy based supply system for microgrids

    SciTech Connect

    Hafez, Omar; Bhattacharya, Kankar

    2012-03-03

    This paper presents a technique for optimal planning and design of hybrid renewable energy systems for microgrid applications. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is used to determine the optimal size and type of distributed energy resources (DERs) and their operating schedules for a sample utility distribution system. Using the DER-CAM results, an evaluation is performed to evaluate the electrical performance of the distribution circuit if the DERs selected by the DER-CAM optimization analyses are incorporated. Results of analyses regarding the economic benefits of utilizing the optimal locations identified for the selected DER within the system are also presented. The actual Brookhaven National Laboratory (BNL) campus electrical network is used as an example to show the effectiveness of this approach. The results show that these technical and economic analyses of hybrid renewable energy systems are essential for the efficient utilization of renewable energy resources for microgird applications.

  6. Post-Closure Inspection Report for Corrective Action Unit 333: U-3auS Disposal Site Annual Report, Nevada Test Site, Nevada

    SciTech Connect

    K. K. Knapp

    2003-09-01

    The U-3auS Disposal Site Corrective Action Unit (CAU) 333 is a closed construction landfill located in Area 3 of the Nevada Test Site. The closure of this site was approved by the Nevada Division of Environmental Protection (NDEP) in a letter to the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office (NNSA/NV) dated June 27, 2001. Post-closure monitoring requirements are described in a letter from NNSA/NV to NDEP dated October 9, 2001, and were approved by the NDEP in a letter from NDEP to NNSA/NV dated November 5, 2001. Post-closure care consists of the following: Semiannual inspections of the unit using an inspection checklist; Photographic documentation of site conditions; Field note documentation; Performing minor site maintenance as necessary; and Preparation and submittal of an annual report. The annual report consists of copies of the inspection checklist, repair records (if any), photographs, and recommendations and conclusions. The Post-Closure Inspection Checklists are provided in Attachment A, a copy of the field notes is found in Attachment B, and copies of the inspection photographs are provided in Attachment C. Field note documentation is not formally required for this CAU, however in order to be consistent with other reports, it has been added to this report.

  7. Diabetes and disability in older Australians: The Australian Diabetes, Obesity and Lifestyle (AusDiab) study.

    PubMed

    Koye, Digsu N; Shaw, Jonathan E; Magliano, Dianna J

    2017-04-01

    To examine the association between diabetes and disability in older Australians and to identify factors that explain this association. We analysed data from a subsample of the Australian Diabetes, Obesity and Lifestyle study (AusDiab) cohort. Disability was measured using the Katz questionnaire in those aged 60years or over and was defined as some difficulty in any of the Katz activities of daily living (ADL) questions. Among 2373 study participants aged 60years or above who had a disability assessment at the third wave of follow-up (2011-12), 255 (11%) reported at least some disability. Participants with diabetes at baseline had higher odds of disability at 12years [odds ratio=2.41 (95% CI 1.60-3.64)] as compared to individuals with normal glucose tolerance; these patterns were similar for men and women. There was no association between baseline prediabetes and disability [OR=1.27 (95% CI 0.91-1.78)]. Baseline body mass index (BMI) and cardiometabolic factors (hypertension, prior cardiovascular disease, impaired glomerular filtration rate, triglycerides and high-density lipoproteins) were important in explaining the increased odds of disability. BMI and cardiometabolic factors together explained 65% of the diabetes-associated odds of disability at 12years. In older Australians, we showed that baseline diabetes more than doubled the odds of reporting disability at 12years, with BMI and cardiometabolic factors accounting for much of this relationship. These findings suggest that interventions targeting weight control, and prevention and treatment of cardiometabolic factors may prevent disability associated with diabetes and promote healthy aging. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Qualitatsentwicklung von Schulen in der Einwanderungsgesellschaft: Evaluation der Lehrerfortbildung zur interkulturellen Koordination (2012- 2014)(Quality Development of Schools in the Immigration Society: Evaluation of lnterculturalCoordination of Teachers (2012 2014))

    DTIC Science & Technology

    2016-08-01

    Programm und der Prazess der Qualifizierung a us der Perspektive der teilnehmenden Lehrkrafte und beteiligter Schul leitungen ana lysiert; (2.) wu...Folgen und Nebenwirkungen der Schulentwicklung erfassen und ana - lysieren zu kiinnen, ermiig lichen insbesondere zwei Traditionen der neueren...ver6ffentlicht wurden, die Erfassung aktue ller Medienberichte, die Auswertung der Interviews mit den Projektleiterinnen sowie die Ana lyse von

  9. Van der Waals interactions: evaluations by use of a statistical mechanical method.

    PubMed

    Høye, Johan S

    2011-10-07

    In this work the induced van der Waals interaction between a pair of neutral atoms or molecules is considered by use of a statistical mechanical method. With use of the Schrödinger equation this interaction can be obtained by standard quantum mechanical perturbation theory to second order. However, the latter is restricted to electrostatic interactions between dipole moments. So with radiating dipole-dipole interaction where retardation effects are important for large separations of the particles, other methods are needed, and the resulting induced interaction is the Casimir-Polder interaction usually obtained by field theory. It can also be evaluated, however, by a statistical mechanical method that utilizes the path integral representation. We here show explicitly by use of this method the equivalence of the Casimir-Polder interaction and the van der Waals interaction based upon the Schrödinger equation. The equivalence is to leading order for short separations where retardation effects can be neglected. In recent works [J. S. Høye, Physica A 389, 1380 (2010); Phys. Rev. E 81, 061114 (2010)], the Casimir-Polder or Casimir energy was added as a correction to calculations of systems like the electron clouds of molecules. The equivalence to van der Waals interactions indicates that the added Casimir energy will improve the accuracy of calculated molecular energies. Thus, we give numerical estimates of this energy including analysis and estimates for the uniform electron gas. © 2011 American Institute of Physics

  10. Energy as a Service

    NASA Astrophysics Data System (ADS)

    Pell, Wolfgang

    Energie wird zum Gebrauchsgegenstand, zur Commodity und rückt doch in den Blickpunkt der Aufmerksamkeit. Volkswirtschaftliche, politische, gesellschaftliche und betriebswirtschaftliche Ansprüche lassen Services rund um die Energieversorgung (Energy-related Services) entstehen. Convenience Services, die den Ansprüchen der Konsumenten gerecht werden, wie Visualisierung von (dezentraler) Energieerzeugung und -verbrauch auf Basis digitaler Smart Meter, die den analogen Ferraris-Zähler ersetzen, sowie optimierter Energieeinsatz halten in Haushalten als digitalisierten Standorten (Smart Sites) Einzug. Energieoptimierung auf Basis des Paradigmas "Verbrauch folgt Erzeugung" stellt Nachfrageflexibilität industrieller Prozesse (Demand Response) als Energie-Effizienz-Faktor in den Vordergrund und lässt Services wie ihre Vermarktung als Regelenergie zur Stabilisierung der Netzfrequenz entstehen. Ein Innovation Action Plan liefert einen Ausblick, wohin die Integration neuer Technologien, die Steigerung der Kundennähe und die Entwicklung neuer Geschäftsmodelle die Energiewirtschaft führen kann. Mit Eco-Home und Power-Pool werden zwei konkrete Beispiele für Energy as a Service vorgestellt.

  11. Characterization of rarefaction waves in van der Waals fluids

    NASA Astrophysics Data System (ADS)

    Yuen, Albert; Barnard, John J.

    2015-12-01

    We calculate the isentropic evolution of an instantaneously heated foil, assuming a van der Waals equation of state with the Maxwell construction. The analysis by Yuen and Barnard [Phys. Rev. E 92, 033019 (2015), 10.1103/PhysRevE.92.033019] is extended for the particular case of three degrees of freedom. We assume heating to temperatures in the vicinity of the critical point. The self-similar profiles of the rarefaction waves describing the evolution of the foil display plateaus in density and temperature due to a phase transition from the single-phase to the two-phase regime. The hydrodynamic equations are expressed in a dimensionless form and the solutions form a set of universal curves, depending on a single parameter: the dimensionless initial entropy. We characterize the rarefaction waves by calculating how the plateau length, density, pressure, temperature, velocity, internal energy, and sound speed vary with dimensionless initial entropy.

  12. Entanglement growth during Van der Waals like phase transition

    NASA Astrophysics Data System (ADS)

    Xu, Hao

    2017-09-01

    We address the problem of describing the coexistence state of two different black holes and Van der Waals like phase transition in Reissner-Nordström-AdS space-time. We start by a small charged black hole, then introduce a collapsing neutral thin-shell described by Vaidya metric to form a large one. The formation of the large black hole does not change the temperature and free energy of the initial state. We discuss the entanglement growing during the phase transition. The transition is always continuous and the saturation time is determined by the final state. It opens a possibility for studying the holography from excited states to excited states.

  13. The vibration of nanosprings affected by van der Waals interactions.

    PubMed

    Zhao, Junhua; Ben, Sudong; Yu, Peishi

    2016-10-01

    The vibration of tightly helical nanosprings affected by van der Waals (vdW) interactions is investigated based on continuum modelling. Explicit solutions are derived to clarify the influence of initial pitch, stiffness and the number of nanosprings on the period, frequency and amplitude of the vibration. Unlike classic linear/nonlinear springs, the waveform of the vibration is always asymmetric for tightly helical nanosprings due to the asymmetry of vdW attraction and repulsion. The at most three equilibrium positions for the nanosprings strongly depend on the deformation due to competition between the vdW interactions and the elastic energy of the nanosprings. This study provides physical insights into the origin of the novel dynamic properties of such nanosprings.

  14. The impact of ancillary services in optimal DER investment decisions

    DOE PAGES

    Cardoso, Goncalo; Stadler, Michael; Mashayekh, Salman; ...

    2017-04-25

    Microgrid resource sizing problems typically include the analysis of a combination of value streams such as peak shaving, load shifting, or load scheduling, which support the economic feasibility of the microgrid deployment. However, microgrid benefits can go beyond these, and the ability to provide ancillary grid services such as frequency regulation or spinning and non-spinning reserves is well known, despite typically not being considered in resource sizing problems. This paper proposes the expansion of the Distributed Energy Resources Customer Adoption Model (DER-CAM), a state-of-the-art microgrid resource sizing model, to include revenue streams resulting from the participation in ancillary service markets.more » Results suggest that participation in such markets may not only influence the optimum resource sizing, but also the operational dispatch, with results being strongly influenced by the exact market requirements and clearing prices.« less

  15. Characterization of rarefaction waves in van der Waals fluids.

    PubMed

    Yuen, Albert; Barnard, John J

    2015-12-01

    We calculate the isentropic evolution of an instantaneously heated foil, assuming a van der Waals equation of state with the Maxwell construction. The analysis by Yuen and Barnard [Phys. Rev. E 92, 033019 (2015)] is extended for the particular case of three degrees of freedom. We assume heating to temperatures in the vicinity of the critical point. The self-similar profiles of the rarefaction waves describing the evolution of the foil display plateaus in density and temperature due to a phase transition from the single-phase to the two-phase regime. The hydrodynamic equations are expressed in a dimensionless form and the solutions form a set of universal curves, depending on a single parameter: the dimensionless initial entropy. We characterize the rarefaction waves by calculating how the plateau length, density, pressure, temperature, velocity, internal energy, and sound speed vary with dimensionless initial entropy.

  16. Renormalization and Universality of Van der Waals forces

    NASA Astrophysics Data System (ADS)

    Ruiz Arriola, Enrique; Calle Cordón, Alvaro

    2010-04-01

    Renormalization ideas can profitably be exploited in conjunction with the superposition principle of boundary conditions in the description of model independent and universal scaling features of the singular and long range Van der Waals force between neutral atoms. The dominance of the leading power law is highlighted both in the scattering as well as in the bound state problem. The role of off-shell two-body unitarity and causality within the Effective Field Theory framework on the light of universality and scaling at low energies is analyzed. Presented by E. Ruiz Arriola at 19th International IUPAP Conference On Few-Body Problems In Physics (FB 19) 31 Aug - 5 Sep 2009, Bonn, Germany

  17. General van der Waals potential for common organic molecules.

    PubMed

    Qi, Rui; Wang, Qiantao; Ren, Pengyu

    2016-10-15

    This work presents a systematic development of a new van der Waals potential (vdW2016) for common organic molecules based on symmetry-adapted perturbation theory (SAPT) energy decomposition. The Buf-14-7 function, as well as Cubic-mean and Waldman-Hagler mixing rules were chosen given their best performance among other popular potentials. A database containing 39 organic molecules and 108 dimers was utilized to derive a general set of vdW parameters, which were further validated on nucleobase stacking systems and testing organic dimers. The vdW2016 potential is anticipated to significantly improve the accuracy and transferability of new generations of force fields for organic molecules. Copyright © 2016. Published by Elsevier Ltd.

  18. Die Kometen der Jahre 1531 bis 1539 und ihre Bedeutung für die spätere Entwicklung der Kometenforschung.

    NASA Astrophysics Data System (ADS)

    Kokott, W.

    Contents: 1. Historisches Umfeld und spätere Entwicklungen. 2. Kometen als Objekte quantitativer Beobachtung im geschlossenen Universum der Epoche. 3. Verlauf der Kometenerscheinungen der Jahre 1531 bis 1539. 4. Die Bedeutung der Kometen der Jahre 1531 bis 1539 für die Entwicklung der Astronomie bis Tycho Brahe und für die Kometentheorie späterer Jahrhunderte. 5. Neuere Literatur und Spezialprobleme.

  19. Ustekinumab in der Therapie der Pustulosis palmoplantaris - Eine Fallserie mit neun Patienten.

    PubMed

    Buder, Valeska; Herberger, Katharina; Jacobi, Arnd; Augustin, Matthias; Radtke, Marc Alexander

    2016-11-01

    Die Pustulosis palmoplantaris ist eine chronisch entzündliche Hauterkrankung, die mit bedeutenden Einschränkungen der Lebensqualität und der Belastbarkeit einhergeht. Aufgrund von Zulassungsbeschränkungen und einem häufig therapierefraktären Verlauf sind die Behandlungsmöglichkeiten limitiert. Nach zuvor frustranen Therapien erhielten 9 Patienten mit Pustulosis palmoplantaris nach Ausschluss einer latenten Tuberkulose Ustekinumab (45 mg Ustekinumab bei < 100 kg Körpergewicht [KG], 90 mg Ustekinumab > 100 kg KG) in Woche 0, 4, 12 und 24. Reguläre Visiten erfolgten nach 4 und 12 Wochen, im weiteren Verlauf alle 12 Wochen. Das Durchschnittsalter bei Therapiebeginn betrug 48 Jahre. Drei Patienten waren männlich. Bei n  =  4 Patienten (44,4 %) wurde eine Verbesserung um 75 % des Palmoplantar-Psoriasis-Area-Severity-Index (PPPASI) erreicht. Insgesamt verbesserte sich der PPPASI nach 24 Wochen durchschnittlich um 71,6 %. Eine komplette Abheilung zeigte sich bei n  =  2 Patienten nach 24 Wochen. Bis auf lokale Injektionsreaktionen und leichte Infekte wurden keine unerwünschten Wirkungen beobachtet. Die Fallserie ist ein weiterer Beleg für die Wirksamkeit und Verträglichkeit von Ustekinumab in der Therapie der Pustulosis palmoplantaris. Zur Beurteilung der Langzeitwirkung und -sicherheit sowie der Wirksamkeit einer intermittierenden Therapie sind kontrollierte Studiendaten sowie Beobachtungen im Rahmen von Patientenregistern notwendig. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  20. Harris-type van der Waals density functional scheme

    NASA Astrophysics Data System (ADS)

    Berland, Kristian; Londero, Elisa; Schröder, Elsebeth; Hyldgaard, Per

    2013-07-01

    Biomolecular systems that involve thousands of atoms are difficult to address with standard density functional theory (DFT) calculations. With the development of sparse-matter methods such as the van der Waals density functional (vdW-DF) method [M. Dion , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.92.246401 92, 246401 (2004)], it is now possible to include the dispersive forces in DFT which are necessary to describe the cohesion and behavior of these systems. vdW-DF implementations can be as efficient as those for traditional DFT. Yet, the computational costs of self-consistently determining the electron wave functions and hence the kinetic-energy repulsion still limit the scope of sparse-matter DFT. We propose to speed up sparse-matter calculations by using the Harris scheme [J. Harris, Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.31.1770 31, 1770 (1985)]; that is, we propose to perform electronic relaxations only for separated fragments (molecules) and use a superposition of fragment densities as a starting point to obtain the total energy non-self-consistently. We evaluate the feasibility of this approach for an adaption of the Harris scheme for non-self-consistent vdW-DF (sfd-vdW-DF). We study four molecular dimers with varying degrees of polarity and find that the sfd scheme accurately reproduces standard non-self-consistent vdW-DF for van der Waals dominated systems but is less accurate for those dominated by polar interactions. Results for the S22 set of typical organic molecular dimers are promising.

  1. Electron response in van der Waals density functionals

    NASA Astrophysics Data System (ADS)

    Hyldgaard, Per

    2013-03-01

    There is significant interest in density functional theory (DFT) of dispersive or van der Waals (vdW) interactions and in DFT studies of sparse systems where vdW forces contribute to the cohesion and behavior. The Rutgers-Chalmers van der Waals density functional (vdW-DF) method [PRL 92, 246401 (2004); PRB 76, 125112 (2007)] is a nonempirical approach to calculate vdW bonding and for DFT characterizations of sparse matter. The vdW-DF framework is defined by a single exchange-correlation density functional that rests on a plasmon-type description for both semilocal components and for a parameter-free evaluation of nonlocal correlation. My talk summarizes a set of vdW-DF studies that seeks to map and analyze details in the vdW-DF electron-response nature. The purpose is in part to extract consequences that can facilitate an experiment-theory comparison that goes beyond binding geometries and energies. The aim is also to seek implications that can help develop the vdW-DF framework. I present an analysis of the relative importance of morphology, screening (image-plane formation), and collective effects in the vdW-DF description of molecular systems. In addition, I compare vdW-DF results with Cu(111) experiments that tests the electron-response behavior in terms of adsorption-induced band shifts, the form of the overall light-molecule physisorption potential, and the corrugation in the kinetic-energy repulsion of molecules at surfaces. Overall, the vdW-DF studies suggest the importance of benchmarking vdW methods across different length scales and by exploring the variation that arise when related structures have a different balance between exchange repulsion and vdW attraction.

  2. van der Waals Density Functional Theory vdW-DFq for Semihard Materials

    NASA Astrophysics Data System (ADS)

    Peng, Qing; de, Suvranu

    There are a large number of materials with mild stiffness, which are not as soft as tissues and not as strong as metals. These semihard materials includes energetic materials, molecular crystals, layered materials, and van der Waals crystals. The integrity and mechanical stability are mainly determined by the interactions between instantaneously induced dipoles, the so called London dispersion force or van der Waals force. It is challenging to accurately model the structural and mechanical properties of these semihard materials in the frame of density functional theory where the non-local correlation functionals are not well known. Here we propose a van der Waals density functional named vdW-DFq to accurately model the density and geometry of semihard materials. Using β-cyclotetramethylene tetranitramine as a prototype, we adjust the enhancement factor of the exchange energy functional with generalized gradient approximations. We find this method to be simple and robust over a wide tuning range when calibrating the functional on-demand with experimental data. With a calibrated value q = 1 . 05 , the proposed vdW-DFq method shows good performance in predicting the geometries of 11 common energetic material molecular crystals and 3 typical layered van der Waals crystals. The authors would like to acknowledge the generous financial support from the Defense Threat Reduction Agency (DTRA) Grant # HDTRA1-13-1-0025.

  3. van der Waals forces in density functional theory: Perturbational long-range electron-interaction corrections

    SciTech Connect

    Angyan, Janos G.; Gerber, Iann C.; Savin, Andreas; Toulouse, Julien

    2005-07-15

    Long-range exchange and correlation effects, responsible for the failure of currently used approximate density functionals in describing van der Waals forces, are taken into account explicitly after a separation of the electron-electron interaction in the Hamiltonian into short- and long-range components. We propose a 'range-separated hybrid' functional based on a local density approximation for the short-range exchange-correlation energy, combined with a long-range exact exchange energy. Long-range correlation effects are added by a second-order perturbational treatment. The resulting scheme is general and is particularly well adapted to describe van der Waals complexes, such as rare gas dimers.

  4. Two dimensional graphene nanogenerator by coulomb dragging: Moving van der Waals heterostructure

    NASA Astrophysics Data System (ADS)

    Zhong, Huikai; Li, Xiaoqiang; Wu, Zhiqian; Zhang, Shengjiao; Xu, Zhijuan; Chen, Hongsheng; Lin, Shisheng

    2015-06-01

    Harvesting energy from environment is the current focus of scientific community. Here, we demonstrate a graphene nanogenerator, which is based on moving van der Waals heterostructure formed between graphene and two dimensional (2D) graphene oxide (GO). This nanogenerator can convert mechanical energy into electricity with a voltage output of around 10 mV. Systematic experiments reveal the generated electricity originates from the coulomb interaction induced momentum transfer between 2D GO and holes in graphene. 2D boron nitride was also demonstrated to be effective in the framework of moving van der Waals heterostructure nanogenerator. This investigation of nanogenerator based on the interaction between 2D macromolecule materials will be important to understand the origin of the flow-induced potential in nanomaterials and may have great potential in practical applications.

  5. Thermal response in van der Waals heterostructures

    NASA Astrophysics Data System (ADS)

    Naidu Gandi, Appala; Alshareef, Husam N.; Schwingenschlögl, Udo

    2017-01-01

    We solve numerically the Boltzmann transport equations of the phonons and electrons to understand the thermoelectric response in heterostructures of M2CO2 (M: Ti, Zr, Hf) MXenes with transition metal dichalcogenide monolayers. Low frequency optical phonons are found to occur as a consequence of the van der Waals bonding, contribute significantly to the thermal transport, and compensate for the reduced contributions of the acoustic phonons (increased scattering cross-sections in heterostructures), such that the thermal conductivities turn out to be similar to those of the bare MXenes. Our results indicate that the important superlattice design approach of thermoelectrics (to reduce the thermal conductivity) may be effective for two-dimensional van der Waals materials when used in conjunction with intercalation.

  6. Thermal response in van der Waals heterostructures.

    PubMed

    Gandi, Appala Naidu; Alshareef, Husam N; Schwingenschlögl, Udo

    2017-01-25

    We solve numerically the Boltzmann transport equations of the phonons and electrons to understand the thermoelectric response in heterostructures of M2CO2 (M: Ti, Zr, Hf) MXenes with transition metal dichalcogenide monolayers. Low frequency optical phonons are found to occur as a consequence of the van der Waals bonding, contribute significantly to the thermal transport, and compensate for the reduced contributions of the acoustic phonons (increased scattering cross-sections in heterostructures), such that the thermal conductivities turn out to be similar to those of the bare MXenes. Our results indicate that the important superlattice design approach of thermoelectrics (to reduce the thermal conductivity) may be effective for two-dimensional van der Waals materials when used in conjunction with intercalation.

  7. Superlubricity using repulsive van der Waals forces.

    PubMed

    Feiler, Adam A; Bergström, Lennart; Rutland, Mark W

    2008-03-18

    Using colloid probe atomic force microscopy, we show that if repulsive van der Waals forces exist between two surfaces prior to their contact then friction is essentially precluded and supersliding is achieved. The friction measurements presented here are of the same order as the lowest ever recorded friction coefficients in liquid, though they are achieved by a completely different approach. A gold sphere attached to an AFM cantilever is forced to interact with a smooth Teflon surface (templated on mica). In cyclohexane, a repulsive van der Waals force is observed that diverges at short separations. The friction coefficient associated with this system is on the order of 0.0003. When the refractive index of the liquid is changed, the force can be tuned from repulsive to attractive and adhesive. The friction coefficient increases as the Hamaker constant becomes more positive and the divergent repulsive force, which prevents solid-solid contact, gets switched off.

  8. Der Begriff mathematischer Schönheit in einer empirisch informierten Ästhetik der Mathematik

    NASA Astrophysics Data System (ADS)

    Müller-Hill, Eva; Spies, Susanne

    Dieses Zitat des britischen Mathematikers G. H. Hardy bringt pointiert die unter praktizierenden Mathematikern, aber auch unter Philosophen der Mathematik weithin akzeptierte Ansicht zum Ausdruck, dass mathematische Schönheit eine nicht zu vernachlässigende Rolle in der mathematischen Forschungspraxis spielt und sowohl interessante ästhetiktheoretische, epistemische als auch ontologische Aspekte aufweist. Danach beeinflusst also das Verständnis dessen, was mathematische Schönheit ist, auch das Verständnis dessen, was Mathematik ist: "Was sind die Träger mathematischer Schönheit?" ist die Frage nach der Art der Gegenstände, für deren Schönheit Mathematiker sich begeistern und nach der sie streben. "Was sind die Kriterien für mathematische Schönheit?" ist die Frage nach den Kategorien, unter denen Mathematiker ihre Arbeit bewerten. Egal, ob sich das Phänomen mathematischer Schönheit als Ausnahmemerkmal oder als ständiger Begleiter mathematischen Tuns erweist - ein adäquates allgemeines Mathematikverständnis sollte dieses Phänomen berücksichtigen und bestenfalls auch erklären können.

  9. AusLAMP long period magnetotellurics: progress update and new insights into Victorian geology and mineral prospectivity

    NASA Astrophysics Data System (ADS)

    Chopping, R. G.; Duan, J.; Czarnota, K.; Kemp, T.

    2016-12-01

    It is becoming generally accepted that world-class mineral deposits have a footprint on a scale of the lithosphere. For this reason, Australia has embarked on the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) to map the conductivity of the mid to lower crust and the lithospheric mantle. AusLAMP is a collaborative project between Geoscience Australia, State and Territory Geological Surveys and Universities. The project aims to collect long-period magnetotelluric data across the Australian continent on a nominal 0.5x0.5° ( 55x55 km) grid. To date, more than 450 sites have been acquired including all sites for the state of Victoria, two-thirds of sites in South Australia and Tasmania, and approximately 25 stations in Western Australia. Progress is ramping up with acquisition to turn to the state of New South Wales, the remainder of South Australia and also acquisition in northern Australia. To support this increasing acquisition activity, additional instruments have been purchased to add to those already in Australia. 3D inversion results are now available for AusLAMP Victoria. In collaboration with the National Computational Infrastructure (NCI), the 3D ModEM codes were optimised for use on the NCI's supercomputer, speeding up large-scale inversions by an order of magnitude. The results of these inversions indicate anomalously conductive lithospheric mantle associated with the central region of Victoria which contains significant mineral deposits and prospectivity, and also anomalous resistive lithosphere associated with the southern extension of the dynamically supported Australian Alps and the Newer Volcanics Province. Modelled conductivities are also consistent with mantle xenolith data from central Victoria. Within the crust, the dominant trend of the data is along elongate north-eastern corridors of conductive material. These results shed new questions on the geological history of this region and the lithospheric architecture of the

  10. Zellulare Nichtlineare Netzwerke: Anwendungen in der Informationstechnologie

    NASA Astrophysics Data System (ADS)

    Tetzlaff, R.

    2007-06-01

    Zellulare Nichtlineare Netzwerke (CNN) wurden 1988 von Chua und Yang (Chua und Yang, 1988) eingeführt. Diese Netzwerke sind dadurch gekennzeichnet, dass eine Zelle, die die kleinste Einheit eines CNN darstellt, nur mit Zellen innerhalb einer bestimmten Umgebung verbunden ist. üblicherweise sind Art und Stärke der Wechselwirkung zwischen zwei Zellen eines CNN translationsinvariant, d.h. sie hängen nur von der relativen Lage beider Zellen zueinander ab. Im Vordergrund aktueller Arbeiten stehen auf derartigen Netzwerken basierende schaltungstechnische Realisierungen mit bis zu 176x144 Zellen, die eine direkte Verbindung zu zweidimensionalen optischen Sensor-Anordnungen aufweisen. Über einen separaten Speicherbereich können die Zellkopplungen eines Netzwerks verändert werden, wodurch eine adaptive Verarbeitung von mehrdimensionalen Sensorsignalen ermöglicht wird. Das kürzlich vorgestellte so genannte EyeRis System (Anafocus Ltd.) enthält zusätzlich noch einen Standardprozessor und stellt (bei einer Größe vergleichbar mit der einer Kreditkarte) daher ein vollständiges superschnelles System zur Informationsverarbeitung dar. In diesem Beitrag sollen, nach einem kurzen Überblick über die Eigenschaften von CNN, aktuelle Realisierungen und exemplarisch eine neuere eigene Anwendung vorgestellt und besprochen werden.

  11. Theory of coherent van der Waals matter.

    PubMed

    Kulić, Igor M; Kulić, Miodrag L

    2014-12-01

    We explain in depth the previously proposed theory of the coherent van der Waals (cvdW) interaction, the counterpart of van der Waals (vdW) force, emerging in spatially coherently fluctuating electromagnetic fields. We show that cvdW driven matter is dominated by many-body interactions, which are significantly stronger than those found in standard van der Waals (vdW) systems. Remarkably, the leading two- and three-body interactions are of the same order with respect to the distance (∝R(-6)), in contrast to the usually weak vdW three-body effects (∝R(-9)). From a microscopic theory we show that the anisotropic cvdW many-body interactions drive the formation of low-dimensional structures such as chains, membranes, and vesicles with very unusual, nonlocal properties. In particular, cvdW chains display a logarithmically growing stiffness with the chain length, while cvdW membranes have a bending modulus growing linearly with their size. We argue that the cvdW anisotropic many-body forces cause local cohesion but also a negative effective "surface tension." We conclude by deriving the equation of state for cvdW materials and propose experiments to test the theory, in particular the unusual three-body nature of cvdW.

  12. Theory of coherent van der Waals matter

    NASA Astrophysics Data System (ADS)

    Kulić, Igor M.; Kulić, Miodrag L.

    2014-12-01

    We explain in depth the previously proposed theory of the coherent van der Waals (cvdW) interaction, the counterpart of van der Waals (vdW) force, emerging in spatially coherently fluctuating electromagnetic fields. We show that cvdW driven matter is dominated by many-body interactions, which are significantly stronger than those found in standard van der Waals (vdW) systems. Remarkably, the leading two- and three-body interactions are of the same order with respect to the distance (∝R-6) , in contrast to the usually weak vdW three-body effects (∝R-9 ). From a microscopic theory we show that the anisotropic cvdW many-body interactions drive the formation of low-dimensional structures such as chains, membranes, and vesicles with very unusual, nonlocal properties. In particular, cvdW chains display a logarithmically growing stiffness with the chain length, while cvdW membranes have a bending modulus growing linearly with their size. We argue that the cvdW anisotropic many-body forces cause local cohesion but also a negative effective "surface tension." We conclude by deriving the equation of state for cvdW materials and propose experiments to test the theory, in particular the unusual three-body nature of cvdW.

  13. Modelling the energy future of Switzerland after the phase out of nuclear power plants

    NASA Astrophysics Data System (ADS)

    Diaz, Paula; Van Vliet, Oscar

    2015-04-01

    HES [Pfenninger, 2015]. It has been specifically design to represent high shares of renewable energy, allowing for the estimation of the Swiss energy transition with high level of detail. Calliope includes topology characteristics of the electricity system, and variability of radiation and wind, which enables the analysis of intermittency in renewable electricity sources, in order to fulfil the electricity demand at all hours. Three energy scenarios are modelled; first, the higher energy production of renewables in Switzerland and the import of natural gas to supply the demand; second, imports of wind power from North Sea with high level of intermittency; and third, imports of solar power from North Africa, with less intermittency but with higher risk of internal turmoil. To summarise, we analyse in detail the energy scenarios of Switzerland when the nuclear power plants will be ceased. A gap currently present in academia, such as the future energy security in Switzerland, is covered by our Calliope modelling. References: Abt, M.; E. Bernhard, A. Kolliker, T. Roth, M. Spicher, L. Stieger, Volkswirtschaftliche Massnahmenanalyse zur Energiestrategie 2050: Tiel I: Gesamtergebnisse und Empfehlungen, Staatssekretariat fur Wirtschaft SECO, Bern, CH, 2012. Busser, M; T. Kaiser, E. Wassermann, K. Ammon, S. Reichen, A. Gunzinger, et al., Energiestrategie 2050 aus Sicht des Energie Trialogs, Energie Trialog Schweiz, 2013. Mathiesen, B. V. and Lund, H. Comparative analyses of seven technologies to facilitate the integration of fluctuating renewable energy sources. IET Renew. Power Gen. 3, 190-204 (2009). Mathys, N. 2012. Modelling contributions to the Swiss energy and environmental challenge. Special issue on energy modelling_introductory article.Swiss journal of economics and statistics. Pfenninger, Stefan. 2015. Calliope: a multi-scale energy systems (MUSES) modeling framework. Available at: http://www.callio.pe/ Piot, M. Energiestrategie 2050 der Schweiz, in: 13. Symp

  14. Jahre Entwicklung der Instandhaltung - von der ausfallorientierten Instandhaltung zum gemeinsamen TPM und RCM

    NASA Astrophysics Data System (ADS)

    Iske, Friedhelm

    Zur Einleitung meines Beitrages möchte ich von einem Gespräch mit einem Mitarbeiter berichten, das ich als junger Vorgesetzter einer Instandhaltungsgruppe 1988 führte. Der engagierte Mitarbeiter feierte damals sein vierzigjähriges Dienstjubiläum und war stolz auf das von ihm Geleistete sowie auf den besonderen Einsatz seiner Altersgruppe, die nach dem Zweiten Weltkrieg das Werk wieder aufgebaut hatte. Auf meine Frage, was denn damals die erste Aufgabe in der Firma war, bekam ich kurz und knapp und mit einer Selbstverständlichkeit die selbstbewusste Antwort: "Unser Pferd füttern und mit dem Pferd die innerbetrieblichen Transporte erledigen“. Als junger, technisch orientierter Vorgesetzter war ich über diese Antwort sehr überrascht. Gedanklich weit entfernt war die Vorstellung, dass in der Vergangenheit Transporte mit einem Pferd erledigt wurden.

  15. Distribution System Voltage Regulation by Distributed Energy Resources

    SciTech Connect

    Ceylan, Oguzhan; Liu, Guodong; Xu, Yan; Tomsovic, Kevin

    2014-01-01

    This paper proposes a control method to regulate voltages in 3 phase unbalanced electrical distribution systems. A constrained optimization problem to minimize voltage deviations and maximize distributed energy resource (DER) active power output is solved by harmony search algorithm. IEEE 13 Bus Distribution Test System was modified to test three different cases: a) only voltage regulator controlled system b) only DER controlled system and c) both voltage regulator and DER controlled system. The simulation results show that systems with both voltage regulators and DER control provide better voltage profile.

  16. Der Telemanipulator daVinci als mechanisches Trackingsystem

    NASA Astrophysics Data System (ADS)

    Käst, Johannes; Neuhaus, Jochen; Nickel, Felix; Kenngott, Hannes; Engel, Markus; Short, Elaine; Reiter, Michael; Meinzer, Hans-Peter; Maier-Hein, Lena

    Der Telemanipulator daVinci (Intuitive Surgical, Sunnyvale, Kalifornien) ist ein M aster-Slave System für roboterassistierte minimalinvasive Chirurgie. Da er über integrierte Gelenksensoren verfügt, kann er unter Verwendung der daVinci-API als mechanisches Trackingsystem verwendet werden. In dieser Arbeit evaluieren wir die Präzision und Genauigkeit eines daVinci mit Hilfe eines Genauigkeitsphantoms mit bekannten Maßen. Der ermittelte Positionierungsfehler liegt in der Größenordnung von 6 mm und ist somit für einen Großteil der medizinischen Fragestellungen zu hoch. Zur Reduktion des Fehlers schlagen wir daher eine Kalibrierung der Gelenksensoren vor.

  17. Zum Wissenschaftsverständnis der modernen Evolutionsbiologie

    NASA Astrophysics Data System (ADS)

    Sommer, Ralf J.

    Die moderne Evolutionsbiologie hat ihren Ursprung in den Arbeiten von Charles Darwin und Alfred Wallace (Darwin 1963). Der gemeinsame Ausgangspunkt des Evolutionsgedanken ist dabei die Beobachtung, dass die biologische Welt nicht konstant ist. Biologische Systeme und alle darin lebenden Organismen unterliegen über längere Zeiträume hinweg einer stetigen Veränderung. Diese grundlegende Eigenschaft biologischer Systeme macht die Biologie zu einer historischen Wissenschaft und stellt einen wichtigen Gegensatz zu großen Teilen der Physik dar. Obwohl die Aussage von der Veränderlichkeit der Arten heute trivial klingt, war sie im 19. Jahrhundert eine Revolution, da die Konstanz der Arten und der Welt eine vorherrschende Stellung im damaligen Weltbild hatte (Amundson 2005).

  18. Devices and applications of van der Waals heterostructures

    NASA Astrophysics Data System (ADS)

    Li, Chao; Zhou, Peng; Zhang, David Wei

    2017-03-01

    Van der Waals heterostructures, composed of individual two-dimensional material have been developing extremely fast. Synthesis of van der Waals heterostructures without the constraint of lattice matching and processing compatibility provides an ideal platform for fundamental research and new device exploitation. We review the approach of synthesis of van der Waals heterostructures, discuss the property of heterostructures and thoroughly illustrate the functional van der Waals heterostructures used in novel electronic and photoelectronic device. Project supported by the National Key Research and Development Program (No. 2016YFA0203900) and the National Natural Science Foundation of China (Nos. 61376093, 61622401).

  19. The electric dipole moments in the ground states of gold oxide, AuO, and gold sulfide, AuS

    NASA Astrophysics Data System (ADS)

    Zhang, Ruohan; Yu, Yuanqin; Steimle, Timothy C.; Cheng, Lan

    2017-02-01

    The B2Σ- - X2Π3/2(0,0) bands of a cold molecular beam sample of gold monoxide, AuO, and gold monosulfide, AuS, have been recorded at high resolution both field free and in the presence of a static electric field. The observed electric field induced splittings and shifts were analyzed to produce permanent electric dipole moments, μ→ e l, of 2.94±0.06 D and 2.22±0.05 D for the X2Π3/2(v = 0) states of AuO and AuS, respectively. A molecular orbital correlation diagram is used to rationalize the trend in ground state μ→ e l values for AuX (X = F, Cl, O, and S) molecules. The experimentally determined μ→ e l are compared to those computed at the coupled-cluster singles and doubles (CCSD) level augmented with a perturbative inclusion of triple excitations (CCSD(T)) level of theory.

  20. Illuminating Australia's conductivity structure at 0.5x0.5° resolution: AusLAMP progress

    NASA Astrophysics Data System (ADS)

    Chopping, R. G.

    2015-12-01

    The Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) collaborative project is a program designed to deploy long period magnetotelluric (MT) stations across the Australian continent at a nominal resolution of 0.5x0.5° (approximately 50 by 50 km). The program brings together Federal and State government geological surveys with universities to acquire these MT data sites. The aim is to use these data to produce a 3D model of the conductivity of Australia to lithospheric depths. To date, the entire state of Victoria has been imaged, along with a large portion of South Australia, and smaller regions in Queensland and New South Wales. A pool of instruments are used for these data collection tranches, with standards for acquisition parameters, processing and modelling developed to ensure consistent data acquisition. We will provide an update on the program, including current deployments, plus an overview of data collected so far. Finally, we will discuss the future acquisition plans of the AusLAMP project.

  1. Der Einfluss von Alitretinoin auf die Lebensqualität bei Patienten mit schwerem chronischen Handekzem: FUGETTA - Beobachtungsstudie unter Praxisbedingungen.

    PubMed

    Augustin, Matthias; Thaçi, Diamant; Kamps, Anja

    2016-12-01

    Alitretinoin ist die einzige zugelassene Behandlung für schweres chronisches Handekzem (CHE), das refraktär gegenüber potenten topischen Corticosteroiden ist. Bei dieser Studie (FUGETTA) wurde die Wirksamkeit von leitliniengerecht angewendetem oralem Alitretinoin sowie dessen Einfluss auf die Lebensqualität (LQ) bei Patienten mit schwerem refraktärem CHE beurteilt. Multizentrische, offene, nichtinterventionelle Beobachtungsstudie, durchgeführt in Deutschland. Die Patienten wurden nach Ermessen ihres behandelnden Arztes mit Alitretinoin 10 mg oder 30 mg einmal täglich über maximal 24 Wochen behandelt. Die Wirksamkeit wurde anhand des Physician Global Assessment (PGA) und des Dermatology Life Quality Index (DLQI) bewertet. Zudem wurden unerwünschte Ereignisse (UE) erfasst. Die Studienpopulation bestand aus 658 Patienten (30 mg: n = 581; 10 mg: n = 77). Bei Beobachtungsbeginn litten die meisten Patienten (83 %) gemäß PGA an einem schweren CHE. Bei Beobachtungsende war das Handekzem bei 48 % der Patienten gemäß PGA vollständig oder fast vollständig abgeheilt (30 mg: 49 %; 10 mg: 43 %). Die mittlere Verbesserung des DLQI-Scores in Woche 24 betrug 58 % (30 mg: mittlere [SD] Veränderung gegenüber dem Ausgangswert -10,4 [8,04]) und 70 % (10 mg: mittlere [SD] Veränderung gegenüber dem Ausgangswert -10,8 [7,29]). Die Gesamtinzidenz von NW war niedrig und in den beiden Gruppen ähnlich. Alitretinoin führte zu einer schnellen, deutlichen Verbesserung der LQ bei Patienten mit schwerem CHE. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  2. Bereits nach Ablauf der Halbwertszeit droht der vollständige Zerfall Die britische Atomic Scientists’ Association, die Ideologie der „objektiven” Wissenschaft und die H-Bombe

    NASA Astrophysics Data System (ADS)

    Laucht, Christoph

    Präsident Harry Trumans Verlautbarung vom 31.1.1950, seine Regierung wolle die Entwicklung der Wasserstoffbombe vorantreiben, fand große Beachtung in den britischen Medien. Die illustrierte Zeitschrift Picture Post widmete der HBombe einen Artikel, der unter anderem kurze Stellungnahmen der britischen Atomwissenschaftler Eric Burhop, Kathleen Lonsdale, Harrie Massey, Rudolf Peierls und Maurice Pryce enthielt, die alle Mitglieder der Atomic Scientists' Association (ASA) waren.

  3. Adsorption of benzene on noble metal surfaces studied by density functional theory with Van der Waals correction.

    PubMed

    Toyoda, Kenji; Hamada, Ikutaro; Yanagisawa, Susumu; Morikawa, Yoshitada

    2011-04-01

    We have studied the atomic geometries and the electronic properties of benzene/metal interfaces by using density functional theoretical (DFT) calculations with van der Waals corrections. Adsorption energies of benzene on Cu(111), Ag(111), and Au(111) surfaces calculated by van der Waals density functional proposed by Dion and co-workers agree reasonably well with experimentally reported values, while those calculated by a semi-empirical van der Waals correction proposed by Grimme are overestimated slightly. The work function change induced by benzene adsorption on the three surfaces are quite well reproduced by the semi-empirical correction, suggesting that weak adsorption geometries can be quite well reproduced by DFT with a semi-empirical dispersion correction scheme.

  4. Site-directed mutagenesis around the CuA site of a polyphenol oxidase from Coreopsis grandiflora (cgAUS1).

    PubMed

    Kaintz, Cornelia; Mayer, Rupert L; Jirsa, Franz; Halbwirth, Heidi; Rompel, Annette

    2015-03-24

    Aurone synthase from Coreopsis grandiflora (cgAUS1), catalyzing conversion of butein to sulfuretin in a type-3 copper center, is a rare example of a polyphenol oxidase involved in anabolism. Site-directed mutagenesis around the CuA site of AUS1 was performed, and recombinant enzymes were analyzed by mass spectrometry. Replacement of the coordinating CuA histidines with alanine resulted in the presence of a single copper and loss of diphenolase activity. The thioether bridge-building cysteine and a phenylalanine over the CuA site, exchanged to alanine, have no influence on copper content but appear to play an important role in substrate binding.

  5. PQScal (Power Quality Score Calculation for Distribution Systems with DER Integration)

    SciTech Connect

    2016-11-21

    Power Quality is of great importance to evaluate the “health” of a distribution system, especially when the distributed energy resource (DER) penetration becomes more significant. The individual components that make up power quality, such as voltage magnitude and unbalance, can be measured in simulations or in the field, however, a comprehensive method to incorporate all of these values into a single score doesn't exist. As a result, we propose a methodology to quantify the power quality health using the single number value, named as Power Quality Score (PQS). The PQS is dependent on six metrics that are developed based on both components that directly impact power quality and those are often reference in the context of power quality. These six metrics are named as System Average Voltage Magnitude Violation Index (SAVMVI), System Average Voltage Fluctuation Index (SAVFI), System Average Voltage Unbalance Index (SAVUI), System Control Device Operation Index (SCDOI), System Reactive Power Demand Index (SRPDI) and System Energy Loss Index (SELI). This software tool, PQScal, is developed based on this novel PQS methodology. Besides of traditional distribution systems, PQScal can also measure the power quality for distribution systems with various DER penetrations. PQScal has been tested on two utility distribution feeders with distinct model characteristics and its effectiveness has been proved. In sum, PQScal can help utilities or other parties to measure the power quality of distribution systems with DER integration easily and effectively.

  6. Molecular recognition by van der Waals interaction between polymers with sequence-specific polarizabilities

    NASA Astrophysics Data System (ADS)

    Lu, Bing-Sui; Naji, Ali; Podgornik, Rudolf

    2015-06-01

    We analyze van der Waals interactions between two rigid polymers with sequence-specific, anisotropic polarizabilities along the polymer backbones, so that the dipole moments fluctuate parallel to the polymer backbones. Assuming that each polymer has a quenched-in polarizability sequence which reflects, for example, the polynucleotide sequence of a double-stranded DNA molecule, we study the van der Waals interaction energy between a pair of such polymers with rod-like structure for the cases where their respective polarizability sequences are (i) distinct and (ii) identical, with both zero and non-zero correlation length of the polarizability correlator along the polymer backbones in the latter case. For identical polymers, we find a novel r-5 scaling behavior of the van der Waals interaction energy for small inter-polymer separation r, in contradistinction to the r-4 scaling behavior of distinct polymers, with furthermore a pronounced angular dependence favoring attraction between sufficiently aligned identical polymers. Such behavior can assist the molecular recognition between polymers.

  7. Molecular recognition by van der Waals interaction between polymers with sequence-specific polarizabilities.

    PubMed

    Lu, Bing-Sui; Naji, Ali; Podgornik, Rudolf

    2015-06-07

    We analyze van der Waals interactions between two rigid polymers with sequence-specific, anisotropic polarizabilities along the polymer backbones, so that the dipole moments fluctuate parallel to the polymer backbones. Assuming that each polymer has a quenched-in polarizability sequence which reflects, for example, the polynucleotide sequence of a double-stranded DNA molecule, we study the van der Waals interaction energy between a pair of such polymers with rod-like structure for the cases where their respective polarizability sequences are (i) distinct and (ii) identical, with both zero and non-zero correlation length of the polarizability correlator along the polymer backbones in the latter case. For identical polymers, we find a novel r(-5) scaling behavior of the van der Waals interaction energy for small inter-polymer separation r, in contradistinction to the r(-4) scaling behavior of distinct polymers, with furthermore a pronounced angular dependence favoring attraction between sufficiently aligned identical polymers. Such behavior can assist the molecular recognition between polymers.

  8. Kanban - der Weg ist das Ziel

    NASA Astrophysics Data System (ADS)

    Aull, Florian; Berlak, Joachim; Dickmann, Eva; Dickmann, Philipp; Fischäder, Holm; Gerlach, Joachim; Henneberg, Jens; Kapalla, Klaus; Kress, Oliver; Kuttler, Robert; Schneider, Herfried M.; Schürle, Philipp; Stellpflug, Franz-Josef; Wannenwetsch, Ralph; Wulz, Johannes; Zäh, Michael F.

    Wenn man aktuell Produktionsbereiche in Deutschland und Europa besucht, fallen im Zusammenhang mit modernen Produktionsmethoden immer öfter die Begriffe Kanban (jap. Karte, Signal) und Pull-Produktion, und dies nicht ohne Stolz, da diese mit dem schillernden Vorbild des Toyota Produktionssystems in Zusammenhang stehen. Tatsächlich ist Kanban ein integraler Bestandteil moderner Produktionssysteme. Blickt man aber im Rahmen von Prozessanalysen hinter die Fassaden", d. h. in die tägliche Praxis der Arbeitsprozesse, wird man schnell desillusioniert - die viel gepriesenen klassischen Kanban-Regeln werden im Tagesgeschäft nicht eingehalten.

  9. Komplexität der Geographie

    NASA Astrophysics Data System (ADS)

    Diekert, Volker; Hertrampf, Ulrich

    Das allgemein als Prototyp eines PSPACE-vollständigen Spiels gesehene Geographiespiel wird bezüglich seiner Komplexität genauer untersucht. Das Interesse der theoretischen Informatik an diesem Spiel wurde sehr durch die Darstellung in dem Lehrbuch von Papadimitriou [Pap94] gefördert. Allerdings bestimmt dieses Lehrbuch nicht die Komplexität des Standardspiels sondern verwendet eine Verallgemeinerung. Die Aussage in dem Lehrbuch bleibt damit etwas unbefriedigend und hinter den Möglichkeiten. Wir zeigen hier, dass die komplexitätstheoretische Charakterisierung schon für die Standardvariante des Spiels gilt.

  10. Interlayer Hybridization in van der Waals Heterostructures

    NASA Astrophysics Data System (ADS)

    Le, Nam; Tran, Huan; Woods, Lilia

    Van der Waals heterostructures composed of chemically inert dissimilar layers are of great interest for fundamental science and applications. The weak interplanar interactions and orbital overlap are expected to bring modifications to the constituent materials. By using first principles simulations, we investigate the properties of several heterostructures, including graphene/silicene, graphene/MoS2, and silicene/MoS2. The calculations reveal superlattice characteristic points in the Brillouin zone associated with the different stacking patterns. Band structures projected on each of the constituents show hybridization features related to specific orbital overlap for each heterostructure. Phonon dispersion spectra for the considered heterostructures are also investigated.

  11. A simplified implementation of van der Waals density functionals for first-principles molecular dynamics applications

    NASA Astrophysics Data System (ADS)

    Wu, Jun; Gygi, François

    2012-06-01

    We present a simplified implementation of the non-local van der Waals correlation functional introduced by Dion et al. [Phys. Rev. Lett. 92, 246401 (2004)] and reformulated by Román-Pérez et al. [Phys. Rev. Lett. 103, 096102 (2009)]. The proposed numerical approach removes the logarithmic singularity of the kernel function. Complete expressions of the self-consistent correlation potential and of the stress tensor are given. Combined with various choices of exchange functionals, five versions of van der Waals density functionals are implemented. Applications to the computation of the interaction energy of the benzene-water complex and to the computation of the equilibrium cell parameters of the benzene crystal are presented. As an example of crystal structure calculation involving a mixture of hydrogen bonding and dispersion interactions, we compute the equilibrium structure of two polymorphs of aspirin (2-acetoxybenzoic acid, C9H8O4) in the P21/c monoclinic structure.

  12. First principles calculations of solid-state thermionic transport in layered van der Waals heterostructures

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoming; Zebarjadi, Mona; Esfarjani, Keivan

    2016-08-01

    This work aims at understanding solid-state energy conversion and transport in layered (van der Waals) heterostructures in contact with metallic electrodes via a first-principles approach. As an illustration, a graphene/phosphorene/graphene heterostructure in contact with gold electrodes is studied by using density functional theory (DFT)-based first principles calculations combined with real space Green's function (GF) formalism. We show that for a monolayer phosphorene, quantum tunneling dominates the transport. By adding more phosphorene layers, one can switch from tunneling-dominated transport to thermionic-dominated transport, resulting in transporting more heat per charge carrier, thus, enhancing the cooling coefficient of performance. The use of layered van der Waals heterostructures has two advantages: (a) thermionic transport barriers can be tuned by changing the number of layers, and (b) thermal conductance across these non-covalent structures is very weak. The phonon thermal conductance of the present van der Waals heterostructure is found to be 4.1 MW m-2 K-1 which is one order of magnitude lower than the lowest value for that of covalently-bonded interfaces. The thermionic coefficient of performance for the proposed device is 18.5 at 600 K corresponding to an equivalent ZT of 0.13, which is significant for nanoscale devices. This study shows that layered van der Waals structures have great potential to be used as solid-state energy-conversion devices.This work aims at understanding solid-state energy conversion and transport in layered (van der Waals) heterostructures in contact with metallic electrodes via a first-principles approach. As an illustration, a graphene/phosphorene/graphene heterostructure in contact with gold electrodes is studied by using density functional theory (DFT)-based first principles calculations combined with real space Green's function (GF) formalism. We show that for a monolayer phosphorene, quantum tunneling dominates the

  13. Steady dynamics of exothermic chemical wave fronts in van der Waals fluids.

    PubMed

    Dumazer, G; Antoine, C; Lemarchand, A; Nowakowski, B

    2009-12-01

    We study the steady dynamics of an exothermic Fisher-Kolmogorov-Petrovsky-Piskunov chemical wave front traveling in a one-dimensional van der Waals fluid. The propagating wave is initiated by a nonuniformity in reactant concentration contrary to usual combustion ignition processes. The heat release and activation energy of the reaction play the role of control parameters. We recently proved that the propagation of an exothermic chemical wave front in a perfect gas displays a forbidden interval of stationary wave front speeds [G. Dumazer, M. Leda, B. Nowakowski, and A. Lemarchand, Phys. Rev. E 78, 016309 (2008)]. We examine how this result is modified for nonideal fluids and determine the effect of the van der Waals parameters and fluid density on the bifurcation between diffusion flames and Chapman-Jouguet detonation waves as heat release increases. Analytical predictions are confirmed by the numerical solution of the hydrodynamic equations including reaction kinetics.

  14. 3D van der Waals σ-model and its topological excitations

    NASA Astrophysics Data System (ADS)

    Bulgadaev, S. A.

    2001-09-01

    It is shown that the 3D vector van der Waals nonlinear σ-model (NSM) on a sphere S2 has two types of topological excitations: reminiscent vortices and instantons of 2D NSM. The first ones, the hedgehogs, are described by the homotopic group π2(S2) = Z and have logarithmic energies. They are an analog of 2D vortices. The second ones, corresponding to 2D instantons, are the hopfions. They are described by the homotopic group π3(S2) = Z, or the Hopf invariant HinZ, and have finite energy. The possibility of a topological phase transition in this model and its applications are briefly discussed.

  15. van der Waals force between positronium and hydrogenic atoms Finite-mass corrections

    NASA Technical Reports Server (NTRS)

    Au, C. K.; Drachman, R. J.

    1986-01-01

    The Feshbach projection-operator formalism is used to derive the asymptotic effective interaction potential between two atoms. Beyond the usual van der Waals potential, falling like x exp -6, three x exp -8 terms are also obtained: an attractive dipole-quadrupole term (absent in the positronium-positronium case because of symmetry), a repulsive energy-dependent term, and a repulsive mass-dependent but energy-independent one. This last term was not obtained by Manson and Ritchie (1985) using an independent method.

  16. Van der Waals Interactions Between Subsystems with Overlapping Electron Density

    NASA Astrophysics Data System (ADS)

    Pavanello, Michele

    2015-03-01

    The subsystem formulation of DFT known as Frozen Density Embedding (FDE) provides a divide-and-conquer approach to Kohn-Sham DFT for weakly bound systems. We claim that a subsystem formulation of DFT can simplify both the theoretical framework and the computational effort for calculating the electronic structure of condensed phase systems. In addition, the naturally subsystem-like form of molecular aggregates makes subsystem DFT a better descriptor of the underlying physics than regular DFT of the supersystem. As an example, we present a novel van der Waals theory based on subsystem DFT which can treat seamlessly non-overlapping as well as overlapping subsystem electron densities. The theory is amenable to sensible approximations, such as RPA, and offers natural algorithms to fold in post-RPA corrections. Application of the theory to the computation of binding energies of dimers in the S22 set, as well as computation of selected potential energy surfaces is presented. M.P. acknowledges funding by NSF IIA-1404739 and CBET-1438493.

  17. Crystal Structures of Mite Allergens Der f 1 and Der p 1 Reveal Differences in Surface-Exposed Residues that May Influence Antibody Binding

    SciTech Connect

    Chruszcz, Maksymilian; Chapman, Martin D.; Vailes, Lisa D.; Stura, Enrico A.; Saint-Remy, Jean-Marie; Minor, Wladek; Pomés, Anna

    2009-12-01

    The Group 1 mite allergens, Der f 1 and Der p 1, are potent allergens excreted by Dermatophagoides farinae and Dermatophagoides pteronyssinus, respectively. The human IgE antibody responses to the Group 1 allergens show more cross-reactivity than the murine IgG antibody responses which are largely species-specific. Here, we report the crystal structure of the mature form of Der f 1, which was isolated from its natural source, and a new, high-resolution structure of mature recombinant Der p 1. Unlike Der p 1, Der f 1 is monomeric both in the crystalline state and in solution. Moreover, no metal binding is observed in the structure of Der f 1, despite the fact that all amino acids involved in Ca{sup 2+} binding in Der p 1 are completely conserved in Der f 1. Although Der p 1 and Der f 1 share extensive sequence identity, comparison of the crystal structures of both allergens revealed structural features which could explain the differences in murine and human IgE antibody responses to these allergens. There are structural differences between Der f 1 and Der p 1 which are unevenly distributed on the allergens' surfaces. This uneven spatial arrangement of conserved versus altered residues could explain both the specificity and cross-reactivity of antibodies against Der f 1 and Der p 1.

  18. An Australian risk prediction model for 30-day mortality after isolated coronary artery bypass: the AusSCORE.

    PubMed

    Reid, Christopher; Billah, Baki; Dinh, Diem; Smith, Julian; Skillington, Peter; Yii, Michael; Seevanayagam, Seven; Mohajeri, Morteza; Shardey, Gil

    2009-10-01

    Our objective was to identify risk factors associated with 30-day mortality after isolated coronary artery bypass grafting in the Australian context and to develop a preoperative model for 30-day mortality risk prediction. Preoperative risk associated with cardiac surgery can be ascertained through a variety of risk prediction models, none of which is specific to the Australian population. Recently, it was shown that the widely used EuroSCORE model validated poorly for an Australian cohort. Hence, a valid model is required to appropriately guide surgeons and patients in assessing preoperative risk. Data from the Australasian Society of Cardiac and Thoracic Surgeons database project was used. All patients undergoing isolated coronary artery bypass grafting between July 2001 and June 2005 were included for analysis. The data were divided into creation and validation sets. The data in the creation set was used to develop the model and then the model was validated in the validation set. Preoperative variables with a P value of less than .25 in chi(2) analysis were entered into multiple logistic regression analysis to develop a preoperative predictive model. Bootstrap and backward elimination methods were used to identify variables that are truly independent predictors of mortality, and 6 candidate models were identified. The Akaike Information Criteria (AIC) and prediction mean square error were used to select the final model (AusSCORE) from this group of candidate models. The AusSCORE model was then validated by average receiver operating characteristic, the P value for the Hosmer-Lemeshow goodness-of-fit test, and prediction mean square error obtained from n-fold validation. Over the 4-year period, 11,823 patients underwent cardiac surgery, of whom 65.9% (7709) had isolated coronary bypass procedures. The 30-day mortality rate for this group was 1.74% (134/7709). Factors selected as independent predictors in the preoperative isolated coronary bypass AusSCORE model

  19. Hawai‘i Distributed Energy Resource Technologies for Energy Security

    SciTech Connect

    None, None

    2012-09-30

    HNEI has conducted research to address a number of issues important to move Hawai‘i to greater use of intermittent renewable and distributed energy resource (DER) technologies in order to facilitate greater use of Hawai‘i's indigenous renewable energy resources. Efforts have been concentrated on the Islands of Hawai‘i, Maui, and O‘ahu, focusing in three areas of endeavor: 1) Energy Modeling and Scenario Analysis (previously called Energy Road mapping); 2) Research, Development, and Validation of Renewable DER and Microgrid Technologies; and 3) Analysis and Policy. These efforts focused on analysis of the island energy systems and development of specific candidate technologies for future insertion into an integrated energy system, which would lead to a more robust transmission and distribution system in the state of Hawai‘i and eventually elsewhere in the nation.

  20. 25 Jahre - Institut fuer Geodaesie, Teil 3: Aus dem Leben des Instituts (25 Years - Institute of Geodesy, Part 3: The Life of the Institute)

    DTIC Science & Technology

    2000-01-01

    wesentlich niedrigeren Preise, in kleinen Gaststdtten ein. Sehr beliebt war das >Tam-Tamo, wo es ftir wenig Geld zdhe Schnitzel und hervorragende Avocados und...ausreichend bemnessen; sie erlaubten insbesondere in der Phase der Erstausstattung eine grol3zUlgige Beschaffung aller ftir Lehre und Forschung...Fakultdt der Rheinischen Friedrich-Wilhelms-Universitat in Bonn auf. Ein besonderes Ereignis unter den damaligen Bedingungen stellte ftir mich ein

  1. Scaling laws for van der Waals interactions in nanostructured materials.

    PubMed

    Gobre, Vivekanand V; Tkatchenko, Alexandre

    2013-01-01

    Van der Waals interactions have a fundamental role in biology, physics and chemistry, in particular in the self-assembly and the ensuing function of nanostructured materials. Here we utilize an efficient microscopic method to demonstrate that van der Waals interactions in nanomaterials act at distances greater than typically assumed, and can be characterized by different scaling laws depending on the dimensionality and size of the system. Specifically, we study the behaviour of van der Waals interactions in single-layer and multilayer graphene, fullerenes of varying size, single-wall carbon nanotubes and graphene nanoribbons. As a function of nanostructure size, the van der Waals coefficients follow unusual trends for all of the considered systems, and deviate significantly from the conventionally employed pairwise-additive picture. We propose that the peculiar van der Waals interactions in nanostructured materials could be exploited to control their self-assembly.

  2. Vom Himmelsmythos zum Weltgesetz. Eine Kulturgeschichte der Astronomie.

    NASA Astrophysics Data System (ADS)

    Bialas, V.

    Contents: I: Die Betrachtung des Himmels im Zeichen des Mythos. 1. Astronomische Spuren der Vorzeit. 2. Naturvölker und Ethnoastronomie. 3. Hochkulturen in Asien und Amerika. 4. Das alte Ägypten. 5. Mesopotamien. 6. Die mythisch-religiöse Erfahrung der Welt und die frühe Astronomie. II: Vom Mythos zum Logos. 7. Antikes Griechenland. 8. Römische Antike und frühes Christentum (ca. 200 v. Chr. - 500 n. Chr.). 9. Astronomie unter dem Zeichen des Islam. 10. Europäisches Mittelalter. 11. Die Astronomie als kulturelles Erbe der Menschheit. III: Die Selbstdifferenzierung des Logos. 12. Das Buch der Natur wird aufgeschlagen. 13. Klassische Astronomie und philosophische Aufklärung (ca. 1700 - 1850). 14. Neue Wege der Kosmosforschung in Astrophysik und Kosmologie (ca. 1850 - 1950). 15. Schlußbetrachtung: Die Frage nach dem Weltbild in verunsicherter Zeit.

  3. The different modes of binding of the dust mite allergens, Der f 7 and Der p 7, on a monoclonal antibody WH9 contribute to the differential reactivity.

    PubMed

    Tai, Hsiao-Yun; Zhou, Jia-Kai; Yeh, Chang-Ching; Tam, Ming F; Sheu, Sheh-Yi; Shen, Horng-Der

    2017-06-28

    Der f 7 and Der p 7 are important house dust mite allergens. An IgE-binding inhibition monoclonal antibody WH9 reacts ten folds stronger against Der p 7 than to Der f 7. The purpose of this study is to identify the antigenic determinant(s) and the structural basis of Der f 7 recognize by WH9. WH9-reactive determinant(s) on Der f 7 was identified by immunoblot and immunoblot inhibition. The 3-D binary complex structures of WH9 and the group 7 allergens were simulated with homology modeling and docking methods. WH9 reacted with the Der f 7 f9 fragment. Among the five site-directed Der f 7 mutants, WH9 showed reduced immunoblot reactivity against Der f 7 S156A, D159A and P160A mutants. Only the wild-type protein and the Der f 7 I157A and L158A mutants can inhibit significantly the WH9-binding against Der f 7. The structural model of the Der f 7-WH9 complex suggests residues S156 and D159 of Der f 7 can bind to WH9 via potential hydrogen bonds. The structure models of Der f 7-WH9 and Der p 7-WH9 complexes revealed that the differential modes of binding of Der p 7 and Der f 7 allergens on WH9 contribute to the differential reactivity of WH9 against the Der f 7 and the Der p 7 mite allergens. Copyright © 2017. Published by Elsevier B.V.

  4. Design und Analyse elektrisch kleiner Antennen für den Einsatz in UHF RFID Transpondern

    NASA Astrophysics Data System (ADS)

    Herschmann, R.; Camp, M.; Eul, H.

    2006-09-01

    RFID Systeme werden seit Anfang der neunziger Jahre mit stetig zunehmender Verbreitung im Bereich der automatischen Produktidentifikation, der Diebstahlsicherung (EAS, Electronic Article Surveillance) und für automatische Zutrittskontrollsysteme eingesetzt. Objekte werden hierzu mit einem Transponder ausgestattet, der aus einer Antenne und einem Chip auf einem Trägermaterial besteht. Von großem Interesse ist die Entwicklung und Optimierung von passiven Transpondern für den Einsatz in UHF RFID Systemen. Diese Transponder beziehen die Energie zum Betrieb des Chips aus dem elektromagnetischen Feld einer Schreib-Leseeinheit. Hierfür ist neben der Anpassung der Eingangsimpedanz der Antenne an die Chipimpedanz auch eine möglichst hohe Bandbreite der Antennen wünschenswert, um die Funktion des Transponders bei Schwankungen der Chipimpedanz und variablen Umgebungsparametern zu gewährleisten. Der aus Platzgründen notwendige Einsatz elektrisch kleiner Antennen bedingt eine möglichst optimale Ausnutzung der zur Verfügung stehenden Fläche auf dem Trägermaterial zur Aufnahme der Antenne. Die vorliegende Arbeit beschreibt ein Verfahren zur Analyse und Synthese neuartiger Antennendesigns auf der Basis parametrisierter meandrierter, spiralförmiger und logarithmisch periodischer Dipole.

  5. Deep Energy Retrofit Guidance for the Building America Solutions Center

    SciTech Connect

    Less, Brennan; Walker, Iain

    2015-01-01

    The U.S. DOE Building America program has established a research agenda targeting market-relevant strategies to achieve 40% reductions in existing home energy use by 2030. Deep Energy Retrofits (DERs) are part of the strategy to meet and exceed this goal. DERs are projects that create new, valuable assets from existing residences, by bringing homes into alignment with the expectations of the 21st century. Ideally, high energy using, dated homes that are failing to provide adequate modern services to their owners and occupants (e.g., comfortable temperatures, acceptable humidity, clean, healthy), are transformed through comprehensive upgrades to the building envelope, services and miscellaneous loads into next generation high performance homes. These guidance documents provide information to aid in the broader market adoption of DERs. They are intended for inclusion in the online resource the Building America Solutions Center (BASC). This document is an assemblage of multiple entries in the BASC, each of which addresses a specific aspect of Deep Energy Retrofit best practices for projects targeting at least 50% energy reductions. The contents are based upon a review of actual DERs in the U.S., as well as a mixture of engineering judgment, published guidance from DOE research in technologies and DERs, simulations of cost-optimal DERs, Energy Star and Consortium for Energy Efficiency (CEE) product criteria, and energy codes.

  6. Design of Au/SPIO composite nanoparticle for facile and biocompatible surface functionalization via Au-S bond

    NASA Astrophysics Data System (ADS)

    Seino, Satoshi; Shibata, Yujin; Yamanaka, Masayuki; Nakagawa, Takashi; Mukai, Yohei; Nakagawa, Shinsaku; Yamamoto, Takao A.

    2013-01-01

    Immobilization of Au nanoparticles on super-paramagnetic iron-oxide (SPIO) enables facile and biocompatible surface functionalization via Au-S bond. Au/SPIO composite nanoparticle is easily modified by thiol-modified polyethylene glycol (PEG-SH), and they are successfully applied on MR tumor imaging. However, its large hydrodynamic size ( 150 nm) still causes the accumulation to liver in vivo. In this study, we controlled the hydrodynamic size of Au/SPIO by testing different raw SPIOs and stabilizing polymers. As the best candidate, Au/Molday-ION which was synthesized from Molday-ION and polyvinyl alcohol comprised the hydrodynamic size of 56 nm. Moreover, PEGylated Au/Molday-ION showed excellent dispersibility in blood serum, with the hydrodynamic size of 65 nm. This surface functionalization strategy is effective for the constructions of magnetic nanocarriers for in vivo applications.

  7. elecTUM: Umsetzung der eLearning-Strategie der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Rathmayer, Sabine; Gergintchev, Ivan

    An der TUM wurde ein umfassendes und integriertes eLearning-Konzept umgesetzt, welches Präsenzstudium und eLearning in allen Leistungsbereichen der Universität miteinander verzahnt. Ein besonderer Schwerpunkt lag dabei in der Schaffung einer effizienten und wettbewerbsfähigen integrierten eLearning Infrastruktur in Hinblick auf die noch weiter steigenden Studienanfängerzahlen ab dem Jahr 2011 sowie die Umsetzung von eBologna. Die Etablierung einer hochschulweiten Lernplattform stellte eine wesentliche Basis für die Umsetzung der eLearning-Strategie dar. Die wissenschaftliche und wirtschaftliche Anschlussfähigkeit im Hinblick auf eine Verwertung der Projektergebnisse wurde durch die aktive Beteiligung an einer Vielzahl hochschulübergreifender Arbeitskreise, Fachtagungen und Kooperationen, vor allem über Organisations- und Dienstleistungsmodelle sowie innovative technische Entwicklungen, sichergestellt.

  8. Optimal investment and scheduling of distributed energy resources with uncertainty in electric vehicles driving schedules

    SciTech Connect

    Cardoso, Goncalo; Stadler, Michael; Bozchalui, Mohammed C.; Sharma, Ratnesh; Marnay, Chris; Barbosa-Povoa, Ana; Ferrao, Paulo

    2013-12-06

    The large scale penetration of electric vehicles (EVs) will introduce technical challenges to the distribution grid, but also carries the potential for vehicle-to-grid services. Namely, if available in large enough numbers, EVs can be used as a distributed energy resource (DER) and their presence can influence optimal DER investment and scheduling decisions in microgrids. In this work, a novel EV fleet aggregator model is introduced in a stochastic formulation of DER-CAM [1], an optimization tool used to address DER investment and scheduling problems. This is used to assess the impact of EV interconnections on optimal DER solutions considering uncertainty in EV driving schedules. Optimization results indicate that EVs can have a significant impact on DER investments, particularly if considering short payback periods. Furthermore, results suggest that uncertainty in driving schedules carries little significance to total energy costs, which is corroborated by results obtained using the stochastic formulation of the problem.

  9. Keim oder kein Keim: Herausforderungen bei der Diagnose mykobakterieller Infektionen der Haut.

    PubMed

    Peters, Franziska; Batinica, Marina; Plum, Georg; Eming, Sabine A; Fabri, Mario

    2016-12-01

    Kutane Mykobakteriosen sind in Deutschland selten. Dennoch ist es für eine frühzeitige Diagnose und anschließende wirksame Behandlung erforderlich, dass diese Krankheitsbilder im ärztlichen Bewusstsein verankert sind. Darüber hinaus stehen Infektionen mit Mykobakterien auf der Liste der Differentialdiagnosen vieler Hautkrankheiten. Diagnosen kutaner Mykobakteriosen beruhen auf klinischen Merkmalen und auf Laboruntersuchungen, einschließlich bakterieller Kulturen, histopathologischer Untersuchungen und PCR-basierten Verfahren. Das Wissen um Möglichkeiten und Grenzen dieser Laboruntersuchungen ist von zentraler Bedeutung, um eine angemessene klinische Entscheidung zu treffen. In diesem Beitrag diskutieren wir die aktuellen diagnostischen Möglichkeiten, die in Verdachtsfällen kutaner Mykobakteriosen zur Verfügung stehen. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  10. Berechnung der auftretenden lokalen Kräfte auf der magnetischen Beschichtung eines magnetischen Rasterkraftmikroskops

    NASA Astrophysics Data System (ADS)

    Preisner, T.; Mathis, W.

    2009-05-01

    Die numerische Berechnung entstehender Kraftwirkungen auf Körper aufgrund magnetischer Wechselwirkungen zwischen diesen, ist in Bezug auf die mechanische Deformation dieser Körper ein noch nicht vollständig gelöstes Problem. In dieser Arbeit wird ein Vergleich vorhandener Kraftberechnungsmethoden hinsichtlich der totalen Kraft anhand eines analytisch berechenbaren Beispiels vorgestellt, sowie Unterschiede der lokalen Kraftdichten dieser Methoden in Anwendung auf die magnetische Beschichtung eines magnetischen Rasterkraftmikroskops aufgezeigt. Due to magnetic interactions between magnetic field inducing bodies, force effects occur on the materials. The numerical computation of those occuring forces with respect to a subsequent structural analysis of a deformable material is still a topic of interest in research. In this paper a comparison between several existent force calculation methods regarding the total force is given for an example with two magnetic cubes. Furthermore, differences are shown concerning the local force densities on the magnetic coating of a magnetic force microscope.

  11. Evaluation Framework and Tools for Distributed Energy Resources

    SciTech Connect

    Gumerman, Etan Z.; Bharvirkar, Ranjit R.; LaCommare, Kristina Hamachi; Marnay , Chris

    2003-02-01

    The Energy Information Administration's (EIA) 2002 Annual Energy Outlook (AEO) forecast anticipates the need for 375 MW of new generating capacity (or about one new power plant) per week for the next 20 years, most of which is forecast to be fueled by natural gas. The Distributed Energy and Electric Reliability Program (DEER) of the Department of Energy (DOE), has set a national goal for DER to capture 20 percent of new electric generation capacity additions by 2020 (Office of Energy Efficiency and Renewable Energy 2000). Cumulatively, this amounts to about 40 GW of DER capacity additions from 2000-2020. Figure ES-1 below compares the EIA forecast and DEER's assumed goal for new DER by 2020 while applying the same definition of DER to both. This figure illustrates that the EIA forecast is consistent with the overall DEER DER goal. For the purposes of this study, Berkeley Lab needed a target level of small-scale DER penetration upon which to hinge consideration of benefits and costs. Because the AEO2002 forecasted only 3.1 GW of cumulative additions from small-scale DER in the residential and commercial sectors, another approach was needed to estimate the small-scale DER target. The focus here is on small-scale DER technologies under 500 kW. The technology size limit is somewhat arbitrary, but the key results of interest are marginal additional costs and benefits around an assumed level of penetration that existing programs might achieve. Berkeley Lab assumes that small-scale DER has the same growth potential as large scale DER in AEO2002, about 38 GW. This assumption makes the small-scale goal equivalent to 380,000 DER units of average size 100 kW. This report lays out a framework whereby the consequences of meeting this goal might be estimated and tallied up. The framework is built around a list of major benefits and a set of tools that might be applied to estimate them. This study lists some of the major effects of an emerging paradigm shift away from central

  12. Van der Waals interactions: Evaluations by use of a statistical mechanical method

    NASA Astrophysics Data System (ADS)

    Høye, Johan S.

    2011-10-01

    In this work the induced van der Waals interaction between a pair of neutral atoms or molecules is considered by use of a statistical mechanical method. With use of the Schrödinger equation this interaction can be obtained by standard quantum mechanical perturbation theory to second order. However, the latter is restricted to electrostatic interactions between dipole moments. So with radiating dipole-dipole interaction where retardation effects are important for large separations of the particles, other methods are needed, and the resulting induced interaction is the Casimir-Polder interaction usually obtained by field theory. It can also be evaluated, however, by a statistical mechanical method that utilizes the path integral representation. We here show explicitly by use of this method the equivalence of the Casimir-Polder interaction and the van der Waals interaction based upon the Schrödinger equation. The equivalence is to leading order for short separations where retardation effects can be neglected. In recent works [J. S. Høye, Physica A 389, 1380 (2010), 10.1016/j.physa.2009.12.003; Phys. Rev. E 81, 061114 (2010)], 10.1103/PhysRevE.81.061114, the Casimir-Polder or Casimir energy was added as a correction to calculations of systems like the electron clouds of molecules. The equivalence to van der Waals interactions indicates that the added Casimir energy will improve the accuracy of calculated molecular energies. Thus, we give numerical estimates of this energy including analysis and estimates for the uniform electron gas.

  13. Spooky correlations and unusual van der Waals forces between gapless and near-gapless molecules

    NASA Astrophysics Data System (ADS)

    Dobson, John F.; Savin, Andreas; Ángyán, János G.; Liu, Ru-Fen

    2016-11-01

    We consider the zero-temperature van der Waals (vdW) interaction between two molecules, each of which has a zero or near-zero electronic gap between a ground state and the first excited state, using a toy model molecule (equilateral H3) as an example. We show that the van der Waals energy between two ground state molecules falls off as D-3 instead of the usual D-6 dependence, when the molecules are separated by distance D. We show that this is caused by a perfect "spooky" correlation between the two fluctuating electric dipoles. The phenomenon is related to, but not the same as, the "resonant" interaction between an electronically excited and a ground state molecule introduced by Eisenschitz and London in 1930. It is also an example of "type C van der Waals non-additivity" recently introduced by one of us [J. F. Dobson, Int. J. Quantum Chem. 114, 1157 (2014)]. Our toy molecule H3 is not stable, but symmetry considerations suggest that a similar vdW phenomenon may be observable, despite Jahn-Teller effects, in molecules with a discrete rotational symmetry and broken inversion symmetry, such as certain metal atom clusters. The motion of the nuclei will need to be included for a definitive analysis of such cases, however.

  14. Spooky correlations and unusual van der Waals forces between gapless and near-gapless molecules.

    PubMed

    Dobson, John F; Savin, Andreas; Ángyán, János G; Liu, Ru-Fen

    2016-11-28

    We consider the zero-temperature van der Waals (vdW) interaction between two molecules, each of which has a zero or near-zero electronic gap between a ground state and the first excited state, using a toy model molecule (equilateral H3) as an example. We show that the van der Waals energy between two ground state molecules falls off as D(-3) instead of the usual D(-6) dependence, when the molecules are separated by distance D. We show that this is caused by a perfect "spooky" correlation between the two fluctuating electric dipoles. The phenomenon is related to, but not the same as, the "resonant" interaction between an electronically excited and a ground state molecule introduced by Eisenschitz and London in 1930. It is also an example of "type C van der Waals non-additivity" recently introduced by one of us [J. F. Dobson, Int. J. Quantum Chem. 114, 1157 (2014)]. Our toy molecule H3 is not stable, but symmetry considerations suggest that a similar vdW phenomenon may be observable, despite Jahn-Teller effects, in molecules with a discrete rotational symmetry and broken inversion symmetry, such as certain metal atom clusters. The motion of the nuclei will need to be included for a definitive analysis of such cases, however.

  15. van der Waals interactions between excited-state atoms and dispersive dielectric surfaces

    NASA Astrophysics Data System (ADS)

    Fichet, M.; Schuller, F.; Bloch, D.; Ducloy, M.

    1995-02-01

    van der Waals interactions between atoms and dielectric surfaces are reinvestigated. To describe the nonretarded interaction potential between a dispersive dielectric surface and an atom in an arbitrary internal energy state, we derive a general expression in terms of an integral, over real frequency, of the combined atom and surface polarizabilities. It is shown that, for excited atoms, the expression is equivalent to the one obtained by Wylie and Sipe [Phys. Rev. A 32, 2030 (1985)]. We thus demonstrate how to extend this approach to excited atoms interacting with birefringent dielectrics. For isotropic dielectrics, a method of integration in closed form allows us to derive an approximate formula for the van der Waals interaction constant in terms of resonance frequencies and oscillator strengths of both the atom and the dielectric. Frequency-dependent ``dielectric reflection'' coefficients are introduced for virtual atomic dipole couplings either in absorption or in emission. In absorption, the reflection coefficient is always positive and smaller than unity. In emission, it may take arbitrary values, positive or negative (corresponding to van der Waals repulsion). Such a behavior is shown to be related to resonant excitation exchange between the atomic system and the dielectric medium, when an atomic transition frequency gets in resonance with a dielectric absorption band. Numerical calculations performed for the cesium-sapphire system are shown to be in good agreement with data obtained by selective-reflection spectroscopy. Finally, experimental tests of the birefringent character of the sapphire response are discussed.

  16. Antiferromagnetism in the van der Waals layered spin-lozenge semiconductor CrTe3

    DOE PAGES

    McGuire, Michael A.; Garlea, V. Ovidiu; KC, Santosh; ...

    2017-04-14

    We have investigated the crystallographic, magnetic, and transport properties of the van der Waals bonded, layered compound CrTe 3 on single-crystal and polycrystalline materials. Furthermore, the crystal structure contains layers made up of lozenge-shaped Cr 4 tetramers. Electrical resistivity measurements show the crystals to be semiconducting, with a temperature dependence consistent with a band gap of 0.3 eV. The magnetic susceptibility exhibits a broad maximum near 300 K characteristic of low dimensional magnetic systems. Weak anomalies are observed in the susceptibility and heat capacity near 55 K, and single-crystal neutron diffraction reveals the onset of long-range antiferromagnetic order at thismore » temperature. Strongly dispersive spin waves are observed in the ordered state. Significant magnetoelastic coupling is indicated by the anomalous temperature dependence of the lattice parameters and is evident in structural optimization in van der Waals density functional theory calculations for different magnetic configurations. The cleavability of the compound is apparent from its handling and is confirmed by first-principles calculations, which predict a cleavage energy 0.5 J / m 2 , similar to graphite. Based on our results, CrTe 3 is identified as a promising compound for studies of low dimensional magnetism in bulk crystals as well as magnetic order in monolayer materials and van der Waals heterostructures.« less

  17. Der f 21, a novel allergen from dermatophagoides farina.

    PubMed

    Wu, Yulan; Jiang, Congli; Li, Meng; Yu, Haiqiong; Xiao, Xiaojun; Fan, Xiaoqin; Lin, Jianli; Liu, Xiaoyu; Zhang, Min; Yang, Pingchang; Liu, Zhigang

    2016-01-01

    The Dermatophagoides farina (D. farina) allergens are an important factor contributing to allergic disease. To identify new allergens is important for diagnosis and treatment of allergic diseases. In this study, we sought to characterize the biological activity of Der f 21 of D. farina. The recombinant Der f 21 protein was characterized by western-blot, ELISA and Skin prick test using clinic patient's serum.An allergic asthma mouse model was established with the rDer f 21 as a specific antigen. The results showed that the sera from 28.9% in 38 dust mite allergic children displayed positive results in response to rDer f 21, and 42% in 98 dust mite allergic patients displayed positive response in skin prick test. In addition, Immune inhibition assays showed there was IgE cross-reactivity between rDer f 21 and rDer f 5. Moreover, an allergic asthma mouse model was established. Airway hyperresponsiveness, serum specific IgE, IgG1, eosinophil infiltration in the allergic mice, interleukin-4(IL-4) and interferon-γ (INF-γ) from spleen cells were markedly increased in the allergic mice. The results demonstrate that Der f 21 is a novel allergen.

  18. Der f 21, a novel allergen from dermatophagoides farina

    PubMed Central

    Wu, Yulan; Jiang, Congli; Li, Meng; Yu, Haiqiong; Xiao, Xiaojun; Fan, Xiaoqin; Lin, Jianli; Liu, Xiaoyu; Zhang, Min; Yang, Pingchang; Liu, Zhigang

    2016-01-01

    The Dermatophagoides farina (D. farina) allergens are an important factor contributing to allergic disease. To identify new allergens is important for diagnosis and treatment of allergic diseases. In this study, we sought to characterize the biological activity of Der f 21 of D. farina. The recombinant Der f 21 protein was characterized by western-blot, ELISA and Skin prick test using clinic patient’s serum.An allergic asthma mouse model was established with the rDer f 21 as a specific antigen. The results showed that the sera from 28.9% in 38 dust mite allergic children displayed positive results in response to rDer f 21, and 42% in 98 dust mite allergic patients displayed positive response in skin prick test. In addition, Immune inhibition assays showed there was IgE cross-reactivity between rDer f 21 and rDer f 5. Moreover, an allergic asthma mouse model was established. Airway hyperresponsiveness, serum specific IgE, IgG1, eosinophil infiltration in the allergic mice, interleukin-4(IL-4) and interferon-γ (INF-γ) from spleen cells were markedly increased in the allergic mice. The results demonstrate that Der f 21 is a novel allergen. PMID:27069539

  19. Leichte Neucodierung von Selenocystein in der Natur

    PubMed Central

    Mukai, Takahito; Englert, Markus; Tripp, H. James; Miller, Corwin; Ivanova, Natalia N.; Rubin, Edward M.; Kyrpides, Nikos C.

    2016-01-01

    Selenocystein (Sec oder U) wird durch Neuzuordnung des Stopp-Codons UGA durch einen Sec-spezifischen Elongationsfaktor und eine charakteristische RNA-Struktur codiert. Um mögliche Codonvariationen zu finden, analysierten wir 6.4 Billionen Basenpaare metagenomischer Daten sowie 24903 mikrobielle Genome für tRNASec-Spezies. UGA ist erwartungsgemäβ das vorherrschende Codon für Sec, allerdings finden wir auch tRNASec-Spezies, die die Stopp-Codons UAG und UAA erkennen, sowie weitere zehn Sense-Codons. Die Synthese von Selenoproteinen durch UAG in Geodermatophilus und Blastococcus sowie durch das Cys-Codon UGA in Aeromonas salmonicida konnte durch metabolische Markierung mit 75Se oder Massenspektrometrie bestätigt werden. Weitere tRNASec-Spezies mit verschiedenen Anticodons ermöglichten es Escherichia coli, die aktive Form des Selenoproteins Formiatdehydrogenase H zu synthetisieren. Der genetische Code ist damit bedeutend flexibler, als bisher angenommen. PMID:27440945

  20. Direct synthesis of van der Waals solids.

    PubMed

    Lin, Yu-Chuan; Lu, Ning; Perea-Lopez, Nestor; Li, Jie; Lin, Zhong; Peng, Xin; Lee, Chia Hui; Sun, Ce; Calderin, Lazaro; Browning, Paul N; Bresnehan, Michael S; Kim, Moon J; Mayer, Theresa S; Terrones, Mauricio; Robinson, Joshua A

    2014-04-22

    The stacking of two-dimensional layered materials, such as semiconducting transition metal dichalcogenides (TMDs), insulating hexagonal boron nitride (hBN), and semimetallic graphene, has been theorized to produce tunable electronic and optoelectronic properties. Here we demonstrate the direct growth of MoS2, WSe2, and hBN on epitaxial graphene to form large-area van der Waals heterostructures. We reveal that the properties of the underlying graphene dictate properties of the heterostructures, where strain, wrinkling, and defects on the surface of graphene act as nucleation centers for lateral growth of the overlayer. Additionally, we show that the direct synthesis of TMDs on epitaxial graphene exhibits atomically sharp interfaces. Finally, we demonstrate that direct growth of MoS2 on epitaxial graphene can lead to a 10(3) improvement in photoresponse compared to MoS2 alone.

  1. Implantate und Verfahren in der Augenheilkunde

    NASA Astrophysics Data System (ADS)

    Neuhann, Tobias H.

    Das in der Medizin mit am häufigsten verwendete Implantat weltweit ist die Intraokulare Linse (IOL). Die Gründe hierfür sind vielschichtig: einmal haben die Operationstechniken in den letzten 30 Jahren eine wesentliche Steigerung an Gleichmäßigkeit, Erfolg und Effizienz erfahren, zum anderen verursachen die gestiegenen Anforderungen des Alltags in den Industrienationen und im Berufsleben den höheren Anspruch an das Sehvermögen. Ist die menschliche Linse Ursache für schlechtes Sehvermögen, besteht meist eine Trübung des Linsenproteins. Diese Trübung nennt wird Volksmund Grauer Star genannt, wissenschaftlich die Katarakt (cataracta). Es gibt unterschiedliche Formen wie angeborene (congenita) oder erworbene, traumatische, krankheitsoder altersbedingte Formen [45]. Wird die eingetrübte Linse nun mittels moderner Operationsverfahren entfernt, muss für Ersatz dieses lichtbrechenden Mediums gesorgt werden [2].

  2. Hyperdislocations in van der Waals Layered Materials.

    PubMed

    Ly, Thuc Hue; Zhao, Jiong; Keum, Dong Hoon; Deng, Qingming; Yu, Zhiyang; Lee, Young Hee

    2016-12-14

    Dislocations are one-dimensional line defects in three-dimensional crystals or periodic structures. It is common that the dislocation networks made of interactive dislocations be generated during plastic deformation. In van der Waals layered materials, the highly anisotropic nature facilitates the formation of such dislocation networks, which is critical for the friction or exfoliation behavior for these materials. By transmission electron microscopy analysis, we found the topological defects in such dislocation networks can be perfectly rationalized in the framework of traditional dislocation theory, which we applied the name "hyperdislocations". Due to the strong pinning effect of hyperdislocations, the state of exfoliation can be easily triggered by 1° twisting between two layers, which also explains the origin of disregistry and frictionlessness for all of the superlubricants that are widely used for friction reduction and wear protection.

  3. Dreiphasenwechselstrom (Drehstrom)

    NASA Astrophysics Data System (ADS)

    Bernstein, Herbert

    Wegen des großen Energiebedarfs reicht für viele Anlagen und Geräte der Einphasenwechselstrom mit U = 230 V nicht mehr aus. Heute ist bei der Erzeugung und Verteilung elektrischer Energie das leistungsfähigere Dreiphasenwechselstrom-System üblich. Abb. 32.1 zeigt die Erzeugung eines Dreiphasenwechselstromes.

  4. Van der Waals equation of state revisited: importance of the dispersion correction.

    PubMed

    de Visser, Sam P

    2011-04-28

    One of the most basic equations of state describing nonideal gases and liquids is the van der Waals equation of state, and as a consequence, it is generally taught in most first year undergraduate chemistry courses. In this work, we show that the constants a and b in the van der Waals equation of state are linearly proportional to the polarizability volume of the molecules in a gas or liquid. Using this information, a new thermodynamic one-parameter equation of state is derived that contains experimentally measurable variables and physics constants only. This is the first equation of state apart from the Ideal Gas Law that contains experimentally measurable variables and physics constants only, and as such, it may be a very useful and practical equation for the description of dilute gases and liquids. The modified van der Waals equation of state describes pV as the sum of repulsive and attractive intermolecular interaction energies that are represented by an exponential repulsion function between the electron clouds of the molecules and a London dispersion component, respectively. The newly derived equation of state is tested against experimental data for several gas and liquid examples, and the agreement is satisfactory. The description of the equation of state as a one-parameter function also has implications on other thermodynamic functions, such as critical parameters, virial coefficients, and isothermal compressibilities. Using our modified van der Waals equation of state, we show that all of these properties are a function of the molecular polarizability volume. Correlations of experimental data confirm the derived proportionalities.

  5. Weight control and breast cancer prevention: are the effects of reduced energy intake equivalent to those of increased energy expenditure?

    PubMed

    Thompson, Henry J; Zhu, Zongjian; Jiang, Weiqin

    2004-12-01

    Failure to prevent adult weight gain is associated with an elevated risk for breast cancer. In general, an increase in body weight is accounted for by excess energy intake relative to energy expenditure. Efforts to control weight gain usually involve either a reduction in energy intake via dietary energy restriction (DER), an increase in energy expenditure via physical activity (PA), or both. However, it is not clear whether preventing weight gain by DER, PA, or their combination has comparable effects on the risk for cancer. Results from preclinical models indicate that DER results in a highly reproducible and dose-dependent inhibition of experimentally induced breast cancer. PA also inhibits mammary carcinogenesis, but whether these effects depend on energy balance is not clear. Emerging evidence indicates that reduced levels of circulating insulin-like growth factor (IGF) 1 (IGF-1) and elevated levels of corticosterone may be involved in DER-mediated protection against cancer; however, conditions of PA reported to protect against cancer can actually increase circulating levels of IGF-1. Mechanistic studies have shown that DER inhibits cell proliferation, creates a proapoptotic environment, and reduces blood vessel density adjacent to premalignant and malignant mammary pathologies; comparable information is not available from preclinical studies of PA and carcinogenesis. Additional research is needed to investigate the equivalence of DER, PA, and their combination in breast cancer prevention under comparable conditions of energy balance.

  6. Nanophysik: Wärmeübertrag auf der Nanometerskala

    NASA Astrophysics Data System (ADS)

    Kittel, Achim

    2006-01-01

    Gegen Ende des 19. Jahrhunderts waren die grundlegenden Prozesse des Wärmeaustauschs verstanden. Die Gesetze dienten dann als Grundlage für die Quantenmechanik. Doch gelten diese Gesetze auch auf der Nanometerskala? In den 1970er-Jahren wurde eine Theorie für den Wärmeübertrag im atomaren Bereich entwickelt. Physiker der Universität Oldenburg überprüften deren Vorhersagen und stießen dabei auf signifikante Abweichungen, welche auf einen Zusammenbruch der klassischen, makroskopischen Elektrodynamik hindeuten.

  7. Kernschmelze Der nachhaltige Einfluss von Nuklearwaffen auf Politik und Wirtschaft

    NASA Astrophysics Data System (ADS)

    Greiner, Bernd

    "Was sollen wir von einer Kultur halten, der die Ethik stets als wesentliches Element des menschlichen Lebens galt, die aber - außer in fachlicher oder spieltheoretischer Terminologie - nicht in der Lage war, über die Möglichkeit zu sprechen, nahezu alle Menschen zu töten?" Der Fragesteller gehört zu den berühmtesten Physikern des 20. Jahrhunderts und zu den nach wie vor Umstrittensten. über ihn wurde in den 1960er Jahren ein international viel beachtetes Theaterstück geschrieben, vor wenigen Jahren gar eine Oper.

  8. Synchronization law for a van der Pol array.

    PubMed

    Peles, Slaven; Wiesenfeld, Kurt

    2003-08-01

    We explore the transition to in-phase synchronization in globally coupled oscillator arrays, and compare results for van der Pol arrays with Josephson junction arrays. Our approach yields in each case an analytically tractable iterative map; the resulting stability formulas are simple because the expansion procedure identifies natural parameter groups. A third example, an array of Duffing-van der Pol oscillators, is found to be of the same fundamental type as the van der Pol arrays, but the Josephson arrays are fundamentally different owing to the absence of self-resonant interactions.

  9. Physik gestern und heute Von der Metallstange zum Hochenergielaser

    NASA Astrophysics Data System (ADS)

    Heering, Peter

    2002-05-01

    Im Mai 1752 wurde in Marly bei Paris auf Anregung des amerikanischen Forschers und Politikers Benjamin Franklin erstmals die elektrische Natur des Blitzes nachgewiesen. Damals beschrieb Franklin auch eine technische Vorrichtung, die als Schutz von Gebäuden vor Blitzschlägen dienen sollte: den Blitzableiter. Diese aus heutiger Sicht scheinbar triviale Vorrichtung wurde aber keineswegs unmittelbar akzeptiert. Und bis heute ist die Forschung zum Schutz von Einrichtungen vor Blitzschlägen nicht abgeschlossen.

  10. Robust 2D topological insulators in van der Waals heterostructures.

    PubMed

    Kou, Liangzhi; Wu, Shu-Chun; Felser, Claudia; Frauenheim, Thomas; Chen, Changfeng; Yan, Binghai

    2014-10-28

    We predict a family of robust two-dimensional (2D) topological insulators in van der Waals heterostructures comprising graphene and chalcogenides BiTeX (X = Cl, Br, and I). The layered structures of both constituent materials produce a naturally smooth interface that is conducive to proximity-induced topological states. First-principles calculations reveal intrinsic topologically nontrivial bulk energy gaps as large as 70-80 meV, which can be further enhanced up to 120 meV by compression. The strong spin-orbit coupling in BiTeX has a significant influence on the graphene Dirac states, resulting in the topologically nontrivial band structure, which is confirmed by calculated nontrivial Z2 index and an explicit demonstration of metallic edge states. Such heterostructures offer a unique Dirac transport system that combines the 2D Dirac states from graphene and 1D Dirac edge states from the topological insulator, and it offers ideas for innovative device designs.

  11. Melker Meilensteine auf dem Weg in ein naturwissenschaftliches Zeitalter - Glanzlichter der Ausstellung zum Internationalen Astronomiejahr 2009 in der Melker Stiftsbibliothek.

    NASA Astrophysics Data System (ADS)

    Beck, Paul G.; Zotti, Georg

    2009-06-01

    Das Mittelalter wird weithin als die dunkle Epoche in der Geschichte der Europäischen Wissenschaften betrachtet, und insbesondere das Leben in den Klöstern galt lange Zeit als frei von jeglichem Interesse für Naturwissenschaften abseits der Medizin. Im Mittelalter galt die Astronomie bloß als Mittel zum Zweck, um religiöse und zivile Kalender erstellen zu können. Durch den Bestand der Handschriftenkammer der Melker Stiftsbibliothek eröffnet sich uns eine neue Sichtweise auf das gegen Ende des Mittelalters wachsende Interesse an den Naturwissenschaften. Dies wurde durch die starke Aufwertung der Klosterbibliothek im Rahmen der 'Melker Reform' im 15. Jahrhundert noch weiter verstärkt. Diese Epoche fällt mit der Frühphase der Universität Wien und der 'ersten Wiener Schule der Astronomie' zusammen. Dieser Artikel beleuchtet ausgewählte astronomischen Werke in der Melker Stiftsbibliothek zwischen dem frühen 9 und dem 18. Jahrhundert. Einen Schwerpunkt stellt das Wirken der Wiener Schule der Astronomie dar, wobei wir u.a. die Melker Abschrift von Peuerbachs Gutachten über den Kometen von 1456 sowie die im Stift Melk durchgeführte Beobachtung der Mondfinsternis von 1457 durch Regiomontanus und Peuerbach beleuchten. Dieser Beitrag ist der einführende Übersichtsartikel zum Ausstellungsprojekt in der Melker Stiftsbibliothek im Rahmen des Internationalen Jahres der Astronomie 2009. The medieval period is commonly seen as a dark epoch for science in Europe. Especially monasteries were seen as institutions without interest in natural sciences except for medicine. Astronomy was allegedly only a tool to construct religious and civil calendars. The inventory of the medieval manuscript collection of the library of the Abbey of Melk allows a new view on the growing interest in the exact sciences towards the end of the medieval ages. This interest was intensified through the increased importance of the monastery library due to the monastery reform

  12. Binding and Diffusion of Lithium in Graphite: Quantum Monte Carlo Benchmarks and Validation of van der Waals Density Functional Methods

    DOE PAGES

    Ganesh, P.; Kim, Jeongnim; Park, Changwon; ...

    2014-11-03

    In highly accurate diffusion quantum Monte Carlo (QMC) studies of the adsorption and diffusion of atomic lithium in AA-stacked graphite are compared with van der Waals-including density functional theory (DFT) calculations. Predicted QMC lattice constants for pure AA graphite agree with experiment. Pure AA-stacked graphite is shown to challenge many van der Waals methods even when they are accurate for conventional AB graphite. Moreover, the highest overall DFT accuracy, considering pure AA-stacked graphite as well as lithium binding and diffusion, is obtained by the self-consistent van der Waals functional vdW-DF2, although errors in binding energies remain. Empirical approaches based onmore » point charges such as DFT-D are inaccurate unless the local charge transfer is assessed. Our results demonstrate that the lithium carbon system requires a simultaneous highly accurate description of both charge transfer and van der Waals interactions, favoring self-consistent approaches.« less

  13. Das Semantic Web als Werkzeug in der biomedizinischen Forschung

    NASA Astrophysics Data System (ADS)

    Stenzhorn, Holger; Samwald, Matthias

    In der biomedizinischen Forschung werden besonders in den letzten Jahren vermehrt enorme Mengen an neuen Daten produziert und diese in Folge verstärkt per Internet veröffentlicht. Viele Experten sehen in dieser Vorgehensweise die Chance zur Entdeckung bisher unbekannter biomedizinischer Erkenntnisse. Um dies jedoch zu ermöglichen, müssen neue Wege gefunden werden, die gewonnenen Daten effizient zu verarbeiten und zu verwalten. In dem vorliegenden Artikel werden die Möglichkeiten betrachtet, die das Semantic Web hierzu anbieten kann. Hierfür werden die relevanten Technologien des Semantic Web im speziellen Kontext der biomedizinischen Forschung betrachtet. Ein Fokus liegt auf der Anwendung von Ontologien in der Biomedizin: Es wird auf deren Vorteile eingegangen, aber auch auf möglichen Probleme, die deren Einsatz in einem erweiterten wissenschaftlichen Umfeld mit sich bringen können.

  14. Ein routine-integrierbares Planungswerkzeug zur operativen Rekonstruktion der Orbita

    NASA Astrophysics Data System (ADS)

    Kleiner, Melanie; Schulze, Dirk; Voss, Pit Jakob; Deserno, Thomas M.

    Bei Frakturen des Orbitabodens kann ein Titangitter zur Rekonstruktion operativ eingesetzt werden. In dieser Arbeit wird ein Planungswerkzeug entwickelt, welches mit Hilfe eines aktiven Konturmodells die Orbita in CT Daten segmentiert, ihr Volumen berechnet und visualisiert. Neben den technischen Integrationsstufen der Funktions- und Präsentationsintegration, welche durch den Einsatz des Medical Imaging Interaction Toolkit (MITK) erreicht werden, sowie der Daten-, und Kontextintegration ist vor allem die Stabilität der eingesetzten Algorithmik für die Routine-Integrierbarkeit wichtig. Erste Stabilitätsuntersuchungen basieren auf 3 von 100 zufällig ausgewählten CT-Datensätzen, wobei das Volumen mit je 50 verschiedenen Startpunkten berechnet wurde. Die so ermittelten Variationskoeffizienten liegen deutlich unterhalb der kritischen 5 % Schwelle.

  15. The toluene-Ar complex: S0 and S1 van der Waals modes, changes to methyl rotation, and torsion-van der Waals vibration coupling.

    PubMed

    Gascooke, Jason R; Lawrance, Warren D

    2013-02-28

    The methyl rotor and van der Waals vibrational levels in the S1 and S0 states of toluene-Ar have been investigated by the technique of two-dimensional laser induced fluorescence (2D-LIF). The S0 van der Waals and methyl rotor levels are reported for the first time, while improved S1 values are presented. The correlations seen in the 2D-LIF images between the S0 and S1 states lead to a reassignment of key features in the S1 ← S0 excitation spectrum. This reassignment reveals that there are significant changes in the methyl rotor levels in the complex compared with those in bare toluene, particularly at low m. The observed rotor energies are explained by the introduction of a three-fold, V3, term in the torsion potential (this term is zero in toluene) and a reduction in the height of the six-fold, V6, barriers in S0 and S1 from their values in bare toluene. The V3 term is larger in magnitude than the V6 term in both S0 and S1. The constants determined are ∣V3(S1)∣ = 33.4 ± 1.0 cm(-1), ∣V3(S0)∣ = 20.0 ± 1.0 cm(-1), V6(S1) = -10.7 ± 1.0 cm(-1), and V6(S0) = -1.7 ± 1.0 cm(-1). The methyl rotor is also found to couple with van der Waals vibration; specifically, the m(") = 2 rotor state couples with the combination level involving one quantum of the long axis bend and m(") = 1. The coupling constant is determined to be 1.9 cm(-1), which is small compared with the values typically reported for torsion-vibration coupling involving ring modes.

  16. Hydrogen bonds and van der waals forces in ice at ambient and high pressures.

    PubMed

    Santra, Biswajit; Klimeš, Jiří; Alfè, Dario; Tkatchenko, Alexandre; Slater, Ben; Michaelides, Angelos; Car, Roberto; Scheffler, Matthias

    2011-10-28

    The first principles methods, density-functional theory and quantum Monte Carlo, have been used to examine the balance between van der Waals (vdW) forces and hydrogen bonding in ambient and high-pressure phases of ice. At higher pressure, the contribution to the lattice energy from vdW increases and that from hydrogen bonding decreases, leading vdW to have a substantial effect on the transition pressures between the crystalline ice phases. An important consequence, likely to be of relevance to molecular crystals in general, is that transition pressures obtained from density-functional theory exchange-correlation functionals which neglect vdW forces are greatly overestimated.

  17. On the choice of inertial axes for interpreting spectroscopic properties of van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Ernesti, Andreas; Hutson, Jeremy M.

    1994-10-01

    Properties such as the dipole moments and nuclear quadrupole coupling constants of van der Waals complexes are important in the determination of intermolecular potential energy surfaces from high-resolution spectra. The properties are often interpreted in terms of angular expectation values. It is shown that, when calculating such properties, it is important to use an inertial axis system that satisfies the Eckart conditions. Projections onto other axes, such as the intermolecular vector or the instantaneous principal axes, can lead to substantial errors when the individual monomers have large moments of inertia.

  18. Microwaves Probe Dipole Blockade and van der Waals Forces in a Cold Rydberg Gas

    NASA Astrophysics Data System (ADS)

    Teixeira, R. Celistrino; Hermann-Avigliano, C.; Nguyen, T. L.; Cantat-Moltrecht, T.; Raimond, J. M.; Haroche, S.; Gleyzes, S.; Brune, M.

    2015-07-01

    We show that microwave spectroscopy of a dense Rydberg gas trapped on a superconducting atom chip in the dipole blockade regime reveals directly the dipole-dipole many-body interaction energy spectrum. We use this method to investigate the expansion of the Rydberg cloud under the effect of repulsive van der Waals forces and the breakdown of the frozen gas approximation. This study opens a promising route for quantum simulation of many-body systems and quantum information transport in chains of strongly interacting Rydberg atoms.

  19. Spectroscopic characterization of van der Waals interactions in a metal organic framework with unsaturated metal centers: MOF-74-Mg.

    PubMed

    Nijem, Nour; Canepa, Pieremanuele; Kong, Lingzhu; Wu, Haohan; Li, Jing; Thonhauser, Timo; Chabal, Yves J

    2012-10-24

    The adsorption energies of small molecules in nanoporous materials are often determined by isotherm measurements. The nature of the interaction and the response of the host material, however, can best be studied by spectroscopic methods. We show here that infrared absorption and Raman spectroscopy measurements together with density functional theory calculations, utilizing the novel van der Waals density functional vdW-DF, constitute a powerful approach to studying the weak van der Waals interactions associated with the incorporation of small molecules in these materials. In particular, we show how vdW-DF assists the interpretation of the vibrational spectroscopy data to uncover the binding sites and energies of these molecules, including the subtle dependence on loading of the IR asymmetric stretch mode of CO(2) when adsorbed in MOF-74-Mg. To gain a better understanding of the adsorption mechanism of CO(2) in MOF-74-Mg, the results are compared with CO within MOF-74-Mg.

  20. Electricity End Uses, Energy Efficiency, and Distributed Energy Resources Baseline

    SciTech Connect

    Schwartz, Lisa; Wei, Max; Morrow, William; Deason, Jeff; Schiller, Steven R.; Leventis, Greg; Smith, Sarah; Leow, Woei Ling; Levin, Todd; Plotkin, Steven; Zhou, Yan

    2017-01-01

    This report was developed by a team of analysts at Lawrence Berkeley National Laboratory, with Argonne National Laboratory contributing the transportation section, and is a DOE EPSA product and part of a series of “baseline” reports intended to inform the second installment of the Quadrennial Energy Review (QER 1.2). QER 1.2 provides a comprehensive review of the nation’s electricity system and cover the current state and key trends related to the electricity system, including generation, transmission, distribution, grid operations and planning, and end use. The baseline reports provide an overview of elements of the electricity system. This report focuses on end uses, electricity consumption, electric energy efficiency, distributed energy resources (DERs) (such as demand response, distributed generation, and distributed storage), and evaluation, measurement, and verification (EM&V) methods for energy efficiency and DERs.

  1. EnergyWeb Screening Criteria Report

    SciTech Connect

    Widergren, Steven E.; Guttromson, Ross T.; Baechler, Michael C.

    2003-01-31

    This report describes a framework for evaluating candidate participants in the Bonneville Power Administration's (BPA) EnergyWeb program. The framework includes definition of system goals, relevant material that characterizes a distributed energy resource (DER) participant, rules for evaluating candidate participants, and a process that utilizes this information to produce a list of the most attractive candidates.

  2. Lifshitz theory of van der Waals pressure in dissipative media

    SciTech Connect

    Zheng Yi; Narayanaswamy, Arvind

    2011-04-15

    We derive a first-principles method of determining the van der Waals or Casimir pressure in a dissipative and dispersive planar multilayered system by calculating the Maxwell stress tensor in a fictitious layer of vacuum, that is eventually made to vanish, introduced in the structure. This is illustrated by calculating the van der Waals pressure in a thin film with dissipative properties embedded between two semi-infinite media.

  3. Modified Van der Waals equation and law of corresponding states

    NASA Astrophysics Data System (ADS)

    Zhong, Wei; Xiao, Changming; Zhu, Yongkai

    2017-04-01

    It is well known that the Van der Waals equation is a modification of the ideal gas law, yet it can be used to describe both gas and liquid, and some important messages can be obtained from this state equation. However, the Van der Waals equation is not a precise state equation, and it does not give a good description of the law of corresponding states. In this paper, we expand the Van der Waals equation into its Taylor's series form, and then modify the fourth order expansion by changing the constant Virial coefficients into their analogous ones. Via this way, a more precise result about the law of corresponding states has been obtained, and the law of corresponding states can then be expressed as: in terms of the reduced variables, all fluids should obey the same equation with the analogous Virial coefficients. In addition, the system of 3 He with quantum effects has also been taken into consideration with our modified Van der Waals equation, and it is found that, for a normal system without quantum effect, the modification on ideal gas law from the Van der Waals equation is more significant than the real case, however, for a system with quantum effect, this modification is less significant than the real case, thus a factor is introduced in this paper to weaken or strengthen the modification of the Van der Waals equation, respectively.

  4. Demographische Entwicklung in der Metropolregion Berlin-Brandenburg

    NASA Astrophysics Data System (ADS)

    Beyer, Wolf; Bluth, Friedrich

    〝Denn eins ist sicher: Die Rente.`` Der vielzitierte Satz des früheren Arbeits- und Sozialministers Norbert Blüm klingt heute vielen wie Hohn. Der Altersaufbau der deutschen Bevölkerung erinnert grafisch immer mehr an einen Baum auf dünnem Stämmchen als an eine Pyramide. Angesichts dessen rücken demographische Entwicklungen mehr und mehr in den Fokus der Öffentlichkeit. Besonders die neuen Bundesländer sind massiv von Abwanderung und einem nie dagewesenen Geburtenrückgang betroffen.DIPL.-GEOGR. UTE C. BAUERsprach mitFRIEDRICH BLUTHundWOLF BEYERüber die Besonderheiten der demographischen Prozesse in Berlin und Brandenburg. Beyer leitete bis Anfang 2004 das brandenburgische Referat für Raumbeobachtung. Seine Aufgabe bestand darin, Planungsgrundlagen für die Gemeinsame Landesplanung Berlin-Brandenburg(GL) zu schaffen. Dazu zählen auch Bevölkerungsprognosen für die Kreise und Städte Brandenburgs. Bluth ist in der Senatsverwaltung für Stadtentwicklung Berlin beschäftigt und leitet dort die Gruppe 〝Stadtwissen, Stadtentwicklungsmonitoring, Bevölkerungsprognose.``

  5. Prä- und perioperative Aspekte der Versorgung dermatochirurgischer Patienten.

    PubMed

    Müller, Cornelia S L; Hubner, Wakiko; Thieme-Ruffing, Sigrid; Pföhler, Claudia; Vogt, Thomas; Volk, Thomas; Gärtner, Barbara C; Bialas, Patric

    2017-02-01

    Die Dermatochirurgie nimmt hinsichtlich vieler Punkte eine Sonderstellung unter den operativen Fächern ein. Hierzu gehört in erster Linie die Tatsache, dass bis auf wenige Ausnahmen fast alle Eingriffe traditionell in Lokal- bzw. Regionalanästhesie und oft auch in räumlich-infrastruktureller Trennung von den großen Zentral-Operationssälen stattfinden können. Die peri- und postoperative Überwachung obliegt dabei dem dermatochirurgischen Operationsteam. Das sui generis kleinere OP-Team hat somit eine ganze Reihe perioperativer Notwendigkeiten zu beachten, um die sich in den "großen" chirurgischen Fächern eine Vielzahl verschiedener beteiligter Fachgruppen gemeinsam kümmern. Hierzu gehören neben Hygieneaspekten, Kenntnissen in der Überwachung der Patienten sowie dem Aspekt der surgical site infections auch Fragen zur postoperativen Schmerztherapie sowie detailliertes pharmakologisches Wissen über die zur Anwendung kommenden Lokalanästhetika und das Handling der damit assoziierten toxischen und allergischen Reaktionen. Eine interdisziplinäre Zusammenarbeit und Verantwortung für den Patienten ist notwendig und erfordert die Erarbeitung und Umsetzung qualitätsorientierter und evidenzbasierter Handlungsanweisungen, die im dermatochirurgischen OP-Setting meist weit über das eigentliche Fach hinausgehen. Ziel dieses Weiterbildungsartikels soll die komprimierte Darstellung der genannten fachübergreifenden Standpunkte bezüglich der wichtigsten perioperativen Aspekte sein. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  6. Distributed Energy Systems: Security Implications of the Grid of the Future

    SciTech Connect

    Stamber, Kevin L.; Kelic, Andjelka; Taylor, Robert A.; Henry, Jordan M; Stamp, Jason E.

    2017-01-01

    Distributed Energy Resources (DER) are being added to the nation's electric grid, and as penetration of these resources increases, they have the potential to displace or offset large-scale, capital-intensive, centralized generation. Integration of DER into operation of the traditional electric grid requires automated operational control and communication of DER elements, from system measurement to control hardware and software, in conjunction with a utility's existing automated and human-directed control of other portions of the system. Implementation of DER technologies suggests a number of gaps from both a security and a policy perspective. This page intentionally left blank.

  7. Cybersecurity for distributed energy resources and smart inverters

    DOE PAGES

    Qi, Junjian; Hahn, Adam; Lu, Xiaonan; ...

    2016-12-01

    The increased penetration of distributed energy resources (DER) will significantly increase the number of devices that are owned and controlled by consumers and third parties. These devices have a significant dependency on digital communication and control, which presents a growing risk from cyber attacks. This paper proposes a holistic attack-resilient framework to protect the the integrated DER and the critical power grid infrastructure from malicious cyber attacks, helping ensure the secure integration of DER without harming the grid reliability and stability. Specifically, we discuss the architecture of the cyber-physical power system with a high penetration of DER and analyze themore » unique cybersecurity challenges introduced by DER integration. Next, we summarize important attack scenarios against DER, propose a systematic DER resilience analysis methodology, and develop effective and quantifiable resilience metrics and design principles. Lastly, we introduce attack prevention, detection, and response measures specifically designed for DER integration across cyber, physical device, and utility layers of the future smart grid.« less

  8. Van der Waals Force Assisted Heat Transfer

    NASA Astrophysics Data System (ADS)

    Sasihithlu, K.; Pendry, J. B.; Craster, R. V.

    2017-02-01

    Phonons (collective atomic vibrations in solids) are more effective in transporting heat than photons. This is the reason why the conduction mode of heat transport in nonmetals (mediated by phonons) is dominant compared to the radiation mode of heat transport (mediated by photons). However, since phonons are unable to traverse a vacuum gap (unlike photons), it is commonly believed that two bodies separated by a gap cannot exchange heat via phonons. Recently, a mechanism was proposed [J. B. Pendry, K. Sasihithlu, and R. V. Craster, Phys. Rev. B 94, 075414 (2016)] by which phonons can transport heat across a vacuum gap - through the Van der Waals interaction between two bodies with gap less than the wavelength of light. Such heat transfer mechanisms are highly relevant for heating (and cooling) of nanostructures; the heating of the flying heads in magnetic storage disks is a case in point. Here, the theoretical derivation for modelling phonon transmission is revisited and extended to the case of two bodies made of different materials separated by a vacuum gap. Magnitudes of phonon transmission, and hence the heat transfer, for commonly used materials in the micro- and nano-electromechanical industry are calculated and compared with the calculation of conduction heat transfer through air for small gaps as well as the heat transfer calculation due to photon exchange.

  9. Modern theory of van der Waals interactions

    NASA Astrophysics Data System (ADS)

    Dobson, John

    2014-03-01

    van der Waals (vdW, dispersion) interactions are important in diverse areas such as colloid, surface and nano science, cohesion of molecular crystals, and biomolecular science. They also provide competition in experiments to discover the fifth fundamental force.While vdW interactions have been understood in principle for a century, their quantitative first-principles prediction and modelling down to chemical contact separations have proven stubbornly difficult because the quantal many-electron problem is involved. After some brief historical material, the current state of the art will be discussed with particular reference to several approaches: pairwise additive, perturbative quantum chemical, vdW-DF, Lifshitz-like scattering, RPA-like, Adiabatic Connection Fluctuation Dissipation / Time Dependent DFT based etc.. A potentially useful classification will be introduced to aid in understanding the physical causes of departures from pairwise additivity, that is from the usual sum of C6R-6 contributions. These departures result in non-standard power law decays of nanostructure vdW interactions as a function of separation D, as well as surprising dependences of the attraction on the number, N, of atoms within each vdW-interacting fragment. Some further recent results on non-additivity will also be presented. Work supported by an Australian Research Council Discovery Grant.

  10. Long-Lived Direct and Indirect Interlayer Excitons in van der Waals Heterostructures.

    PubMed

    Miller, Bastian; Steinhoff, Alexander; Pano, Borja; Klein, Julian; Jahnke, Frank; Holleitner, Alexander; Wurstbauer, Ursula

    2017-09-13

    We report the observation of a doublet structure in the low-temperature photoluminescence of interlayer excitons in heterostructures consisting of monolayer MoSe2 and WSe2. Both peaks exhibit long photoluminescence lifetimes of several tens of nanoseconds up to 100 ns verifying the interlayer nature of the excitons. The energy and line width of both peaks show unusual temperature and power dependences. While the low-energy peak dominates the spectra at low power and low temperatures, the high-energy peak dominates for high power and temperature. We explain the findings by two kinds of interlayer excitons being either indirect or quasi-direct in reciprocal space. Our results provide fundamental insights into long-lived interlayer states in van der Waals heterostructures with possible bosonic many-body interactions.

  11. Efficient implementation of a van der Waals density functional: application to double-wall carbon nanotubes.

    PubMed

    Román-Pérez, Guillermo; Soler, José M

    2009-08-28

    We present an efficient implementation of the van der Waals density functional of Dion et al. [Phys. Rev. Lett. 92, 246401 (2004)], which expresses the nonlocal correlation energy as a double spatial integral. We factorize the integration kernel and use fast Fourier transforms to evaluate the self-consistent potential, total energy, and atomic forces, in O(NlogN) operations. The resulting overhead, for medium and large systems, is a small fraction of the total computational cost, representing a dramatic speedup over the O(N(2)) evaluation of the double integral. This opens the realm of first-principles simulations to the large systems of interest in soft matter and biomolecular problems. We apply the method to calculate the binding energies and the barriers for relative translation and rotation in double-wall carbon nanotubes.

  12. Van der Waals interactions between polymers with sequence-specific polarizabilities: Stiff polymers and Gaussian coils

    NASA Astrophysics Data System (ADS)

    Lu, Bing-Sui; Naji, Ali; Podgornik, Rudolf

    2016-01-01

    We consider the van der Waals interaction between a pair of polymers with quenched heterogeneous sequences of local polarizabilities along their backbones, and study the effective pairwise interaction energy for both stiff polymers and flexible Gaussian coils. In particular, we focus on the cases where the pair of polarizability sequences are (i) distinct and (ii) identical. We find that the pairwise interaction energies of distinct and identical Gaussian coils are both isotropic and exhibit the same decay behavior for separations larger than their gyration radius, in contradistinction to the orientationally anisotropic interaction energies of distinct and identical stiff polymers. For both Gaussian coils and stiff polymers, the attractive interaction between identical polymers is enhanced if the polarizability sequence is more heterogeneous.

  13. Lithospheric reworking at the Proterozoic-Phanerozoic transition of Australia imaged using AusLAMP Magnetotelluric data

    NASA Astrophysics Data System (ADS)

    Robertson, Kate; Heinson, Graham; Thiel, Stephan

    2016-10-01

    Seventy-four stations from the long-period Australia-wide AusLAMP (Australian Lithospheric Architecture Magnetotelluric Project) dataset were used to image the electrical resistivity beneath the Neoproterozoic Ikara-Flinders Ranges and adjacent Palaeo-Mesoproterozoic Curnamona Province. Results from 3D inversions using ModEM software show a relatively resistive Ikara-Flinders Ranges, with two parallel arcuate conductors at 20 to 80 km depth in the Nackara Arc. There is a good correlation of diamondiferous kimberlites occurring over conductors, which we interpret as evidence for these conductors to be residing on large lithospheric structures that have been conduits for partial melt and volatile movement in the Jurassic. The Curnamona Province is remarkably conductive for a region that is thought to have a cratonic core, with Delamerian reworking only at its edges. The conductor covers most of the province at depths of 10-40 km, and its presence at lower crustal depths suggests that conductive sediments can not entirely explain it. Fluids associated with subduction may have pervasively modified the crust in the past, resulting in an enrichment of carbon, enhancing the conductivity. Additionally, we conclude that the notion of a single continuous arcuate Flinders Conductivity Anomaly is unlikely and that the anomalous response observed is instead a result of the combined response of three separate anomalies; the Curnamona Province Conductor and the two Nackara Arc Conductors.

  14. Description of the ambulance services participating in the Aus-ROC Australian and New Zealand out-of-hospital cardiac arrest Epistry.

    PubMed

    Beck, Ben; Bray, Janet E; Smith, Karen; Walker, Tony; Grantham, Hugh; Hein, Cindy; Thorrowgood, Melanie; Smith, Anthony; Inoue, Madoka; Smith, Tony; Dicker, Bridget; Swain, Andy; Bosley, Emma; Pemberton, Katherine; McKay, Michael; Johnston-Leek, Malcolm; Cameron, Peter; Perkins, Gavin D; Finn, Judith

    2016-12-01

    The present study aimed to describe and examine similarities and differences in the current service provision and resuscitation protocols of the ambulance services participating in the Aus-ROC Australian and New Zealand out-of-hospital cardiac arrest (OHCA) Epistry. Understanding these similarities and differences is important in identifying ambulance service factors that might explain regional variation in survival of OHCA in the Aus-ROC Epistry. A structured questionnaire was completed by each of the ambulance services participating in the Aus-ROC Epistry. These ambulance services were SA Ambulance Service, Ambulance Victoria, St John Ambulance Western Australia, Queensland Ambulance Service, St John Ambulance NT, St John New Zealand and Wellington Free Ambulance. The survey aimed to describe ambulance service and dispatch characteristics, resuscitation protocols and details of cardiac arrest registries. We observed similarities between services with respect to the treatment of OHCA and dispatch systems. Differences between services were observed in the serviced population; the proportion of paramedics with basic life support, advanced life support or intensive care training skills; the number of OHCA cases attended; guidelines related to withholding or terminating resuscitation attempts; and the variables that might be used to define 'attempted resuscitation'. All seven participating ambulance services were noted to have existing OHCA registries. There is marked variation between ambulance services currently participating in the Aus-ROC Australian and New Zealand OHCA Epistry with respect to workforce characteristics and key variable definitions. This variation between ambulance services might account for a proportion of the regional variation in survival of OHCA. © 2016 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  15. Quantitative Understanding of van der Waals Interactions by Analyzing the Adsorption Structure and Low-Frequency Vibrational Modes of Single Benzene Molecules on Silver.

    PubMed

    Yuan, Dingwang; Han, Zhumin; Czap, Gregory; Chiang, Chi-Lun; Xu, Chen; Ho, W; Wu, Ruqian

    2016-06-16

    The combination of a sub-Kelvin scanning tunneling microscope and density functional calculations incorporating van der Waals (vdW) corrections has been used successfully to probe the adsorption structure and low-frequency vibrational modes of single benzene molecules on Ag(110). The inclusion of optimized vdW functionals and improved C6-based vdW dispersion schemes in density functional theory is crucial for obtaining the correct adsorption structure and low-energy vibrational modes. These results demonstrate the emerging capability to quantitatively probe the van der Waals interactions between a physisorbed molecule and an inert substrate.

  16. Energy manager design for microgrids

    SciTech Connect

    Firestone, Ryan; Marnay, Chris

    2005-01-01

    On-site energy production, known as distributed energy resources (DER), offers consumers many benefits, such as bill savings and predictability, improved system efficiency, improved reliability, control over power quality, and in many cases, greener electricity. Additionally, DER systems can benefit electric utilities by reducing congestion on the grid, reducing the need for new generation and transmission capacity, and offering ancillary services such as voltage support and emergency demand response. Local aggregations of distributed energy resources (DER) that may include active control of on-site end-use energy devices can be called microgrids. Microgrids require control to ensure safe operation and to make dispatch decisions that achieve system objectives such as cost minimization, reliability, efficiency and emissions requirements, while abiding by system constraints and regulatory rules. This control is performed by an energy manager (EM). Preferably, an EM will achieve operation reasonably close to the attainable optimum, it will do this by means robust to deviations from expected conditions, and it will not itself incur insupportable capital or operation and maintenance costs. Also, microgrids can include supervision over end-uses, such as curtailing or rescheduling certain loads. By viewing a unified microgrid as a system of supply and demand, rather than simply a system of on-site generation devices, the benefits of integrated supply and demand control can be exploited, such as economic savings and improved system energy efficiency.

  17. Auranofin disrupts selenium metabolism in Clostridium difficile by forming a stable Au-Se adduct.

    PubMed

    Jackson-Rosario, Sarah; Cowart, Darin; Myers, Andrew; Tarrien, Rebecca; Levine, Rodney L; Scott, Robert A; Self, William Thomas

    2009-05-01

    Clostridium difficile is a nosocomial pathogen whose incidence and importance are on the rise. Previous work in our laboratory characterized the central role of selenoenzyme-dependent Stickland reactions in C. difficile metabolism. In this work we have identified, using mass spectrometry, a stable complex formed upon reaction of auranofin (a gold-containing drug) with selenide in vitro. X-ray absorption spectroscopy supports the structure that we proposed on the basis of mass-spectrometric data. Auranofin potently inhibits the growth of C. difficile but does not similarly affect other clostridia that do not utilize selenoproteins to obtain energy. Moreover, auranofin inhibits the incorporation of radioisotope selenium ((75)Se) in selenoproteins in both Escherichia coli, the prokaryotic model for selenoprotein synthesis, and C. difficile without impacting total protein synthesis. Auranofin blocks the uptake of selenium and results in the accumulation of the auranofin-selenide adduct in the culture medium. Addition of selenium in the form of selenite or L-selenocysteine to the growth medium significantly reduces the inhibitory action of auranofin on the growth of C. difficile. On the basis of these results, we propose that formation of this complex and the subsequent deficiency in available selenium for selenoprotein synthesis is the mechanism by which auranofin inhibits C. difficile growth. This study demonstrates that targeting selenium metabolism provides a new avenue for antimicrobial development against C. difficile and other selenium-dependent pathogens.

  18. Stufenweise Integration von eLearning an der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Pätzold, Sebastian; Graf, Stephan; Gergintchev, Ivan; Pongratz, Hans; Rathmayer, Sabine

    Der vorliegende Beitrag beschreibt als Best Practice Beispiel die stufenweise Integration eines Learning Management Systems (LMS) in die Infrastruktur von Information und Kommunikation (IuK) der Technischen Universität München (TUM). Dabei wird sowohl die Konsolidierung mehrfach angebotener Funktionalitäten und Dienste in den verschiedenen Portalen der Universität als auch die sukzessive Optimierung der Abläufe aufgezeigt. Gleichzeitig wird auf zukünftige weitere Entwicklungen hin zu einer vollständigen Integration der IuK, aber auch auf die Probleme in den unterschiedlichen Stadien der Entwicklung eingegangen.

  19. Van der Waals and resonance interactions between accelerated atoms in vacuum and the Unruh effect

    NASA Astrophysics Data System (ADS)

    Lattuca, M.; Marino, J.; Noto, A.; Passante, R.; Rizzuto, L.; Spagnolo, S.; Zhou, W.

    2017-08-01

    We discuss different physical effects related to the uniform acceleration of atoms in vacuum, in the framework of quantum electrodynamics. We first investigate the van der Waals/Casimir-Polder dispersion and resonance interactions between two uniformly accelerated atoms in vacuum. We show that the atomic acceleration significantly affects the van der Waals force, yielding a different scaling of the interaction with the interatomic distance and an explicit time dependence of the interaction energy. We argue how these results could allow for an indirect detection of the Unruh effect through dispersion interactions between atoms. We then consider the resonance interaction between two accelerated atoms, prepared in a correlated Bell-type state, and interacting with the electromagnetic field in the vacuum state, separating vacuum fluctuations and radiation reaction contributions, both in the free-space and in the presence of a perfectly reflecting plate. We show that nonthermal effects of acceleration manifest in the resonance interaction, yielding a change of the distance dependence of the resonance interaction energy. This suggests that the equivalence between temperature and acceleration does not apply to all radiative properties of accelerated atoms. To further explore this aspect, we evaluate the resonance interaction between two atoms in non inertial motion in the coaccelerated (Rindler) frame and show that in this case the assumption of an Unruh temperature for the field is not required for a complete equivalence of locally inertial and coaccelerated points of views.

  20. Band Alignment and Minigaps in Monolayer MoS2-Graphene van der Waals Heterostructures.

    PubMed

    Pierucci, Debora; Henck, Hugo; Avila, Jose; Balan, Adrian; Naylor, Carl H; Patriarche, Gilles; Dappe, Yannick J; Silly, Mathieu G; Sirotti, Fausto; Johnson, A T Charlie; Asensio, Maria C; Ouerghi, Abdelkarim

    2016-07-13

    Two-dimensional layered MoS2 shows great potential for nanoelectronic and optoelectronic devices due to its high photosensitivity, which is the result of its indirect to direct band gap transition when the bulk dimension is reduced to a single monolayer. Here, we present an exhaustive study of the band alignment and relativistic properties of a van der Waals heterostructure formed between single layers of MoS2 and graphene. A sharp, high-quality MoS2-graphene interface was obtained and characterized by micro-Raman spectroscopy, high-resolution X-ray photoemission spectroscopy (HRXPS), and scanning high-resolution transmission electron microscopy (STEM/HRTEM). Moreover, direct band structure determination of the MoS2/graphene van der Waals heterostructure monolayer was carried out using angle-resolved photoemission spectroscopy (ARPES), shedding light on essential features such as doping, Fermi velocity, hybridization, and band-offset of the low energy electronic dynamics found at the interface. We show that, close to the Fermi level, graphene exhibits a robust, almost perfect, gapless, and n-doped Dirac cone and no significant charge transfer doping is detected from MoS2 to graphene. However, modification of the graphene band structure occurs at rather larger binding energies, as the opening of several miniband-gaps is observed. These miniband-gaps resulting from the overlay of MoS2 and the graphene layer lattice impose a superperiodic potential.

  1. Structural and quantum properties of van der Waals cluster near the unitary regime

    NASA Astrophysics Data System (ADS)

    Lekala, M. L.; Chakrabarti, B.; Haldar, S. K.; Roy, R.; Rampho, G. J.

    2017-07-01

    We study the structural and several quantum properties of three-dimensional bosonic cluster interacting through van der Waals potential at large scattering length. We use Faddeev-type decomposition of the many-body wave function which includes all possible two-body correlations. At large scattering length, we observe spatially extended states which exhibit the exponential dependence on the state number. The cluster ground state energy shows universal nature at large negative scattering length. We also find the existence of generalized Tjon lines for N-body clusters. Signature of universal behaviour of weakly bound clusters can be observed in experiments of ultracold Bose gases. We also study the spectral statistics of the system. We calculate both the short-range fluctuation and long-range correlation and observe semi-Poisson distribution which interpolates the Gaussian Orthogonal Ensemble (GOE) and Poisson statistics of random matrix theory. It indicates that the van der Waal cluster near the unitary becomes highly complex and correlated. However additional study of P (r) distribution (without unfolding of energy spectrum) reveals the possibility of chaos for larger cluster.

  2. Energy Technology Allocation for Distributed Energy Resources: A Technology-Policy Framework

    NASA Astrophysics Data System (ADS)

    Mallikarjun, Sreekanth

    Distributed energy resources (DER) are emerging rapidly. New engineering technologies, materials, and designs improve the performance and extend the range of locations for DER. In contrast, constructing new or modernizing existing high voltage transmission lines for centralized generation are expensive and challenging. In addition, customer demand for reliability has increased and concerns about climate change have created a pull for swift renewable energy penetration. In this context, DER policy makers, developers, and users are interested in determining which energy technologies to use to accommodate different end-use energy demands. We present a two-stage multi-objective strategic technology-policy framework for determining the optimal energy technology allocation for DER. The framework simultaneously considers economic, technical, and environmental objectives. The first stage utilizes a Data Envelopment Analysis model for each end-use to evaluate the performance of each energy technology based on the three objectives. The second stage incorporates factor efficiencies determined in the first stage, capacity limitations, dispatchability, and renewable penetration for each technology, and demand for each end-use into a bottleneck multi-criteria decision model which provides the Pareto-optimal energy resource allocation. We conduct several case studies to understand the roles of various distributed energy technologies in different scenarios. We construct some policy implications based on the model results of set of case studies.

  3. Deep Energy Retrofits - Eleven California Case Studies

    SciTech Connect

    Less, Brennan; Fisher, Jeremy; Walker, Iain

    2012-10-01

    This research documents and demonstrates viable approaches using existing materials, tools and technologies in owner-conducted deep energy retrofits (DERs). These retrofits are meant to reduce energy use by 70% or more, and include extensive upgrades to the building enclosure, heating, cooling and hot water equipment, and often incorporate appliance and lighting upgrades as well as the addition of renewable energy. In this report, 11 Northern California (IECC climate zone 3) DER case studies are described and analyzed in detail, including building diagnostic tests and end-use energy monitoring results. All projects recognized the need to improve the home and its systems approximately to current building code-levels, and then pursued deeper energy reductions through either enhanced technology/ building enclosure measures, or through occupant conservation efforts, both of which achieved impressive energy performance and reductions. The beyond-code incremental DER costs averaged $25,910 for the six homes where cost data were available. DERs were affordable when these incremental costs were financed as part of a remodel, averaging a $30 per month increase in the net-cost of home ownership.

  4. Evolutionary design of interfacial phase change van der Waals heterostructures.

    PubMed

    Kalikka, Janne; Zhou, Xilin; Behera, Jitendra; Nannicini, Giacomo; Simpson, Robert E

    2016-10-27

    We use an evolutionary algorithm to explore the design space of hexagonal Ge2Sb2Te5; a van der Waals layered two dimensional crystal heterostructure. The Ge2Sb2Te5 structure is more complicated than previously thought. Predominant features include layers of Ge3Sb2Te6 and Ge1Sb2Te4 two dimensional crystals that interact through Te-Te van der Waals bonds. Interestingly, (Ge/Sb)-Te-(Ge/Sb)-Te alternation is a common feature for the most stable structures of each generation's evolution. This emergent rule provides an important structural motif that must be included in the design of high performance Sb2Te3-GeTe van der Waals heterostructure superlattices with interfacial atomic switching capability. The structures predicted by the algorithm agree well with experimental measurements on highly oriented, and single crystal Ge2Sb2Te5 samples. By analysing the evolutionary algorithm optimised structures, we show that diffusive atomic switching is probable by Ge atoms undergoing a transition at the van der Waals interface from layers of Ge3Sb2Te6 to Ge1Sb2Te4 thus producing two blocks of Ge2Sb2Te5. Evolutionary methods present an efficient approach to explore the enormous multi-dimensional design parameter space of van der Waals bonded heterostructure superlattices.

  5. Topologie und Dynamische Netzwerke: Anwendungen Der Optimierung MIT Zukunft

    NASA Astrophysics Data System (ADS)

    Leugering, Günter; Martin, Alexander; Stingl, Michael

    Die optimale Auslegung von Infrastrukturen z. B. bei der Verkehrsplanung und bei der Planung von Versorgungssystemen, die optimale Strukturierung bzw. Formgebung von Materialien und Werkstücken z. B. im Leichtbau sind aktuelle Themen angewandter Forschung. In beiden Bereichen wurde bis in die jüngste Zeit vornehmlich eine simulationsbasierte Optimierung auf der Grundlage einer Parameterjustierung vorgenommen, die oft wenig systematisch und zeit- und kostenintensiv ist. Stattdessen erweisen sich modellbasierte mathematische Optimierungsalgorithmen zusammen mit moderner numerischer Simulations-und Visualisierungstechnologie zunehmend als Katalysator neuer Technologien. Eine so verstandene Mathematische Optimierung kann bereits auf beeindruckende Erfolgsgeschichten verweisen und so den Anspruch als eine Zukunftsdisziplin behaupten. Diesem Anspruch trägt die Einrichtung des DFG-Schwerpunktprogramms 1253, Optimierung mit partiellen Differentialgleichungen’ im Jahre 2006 Rechnung, in dem über 25 Projekte im Bundesgebiet sowohl auf die theoretische Fundierung, als auch und insbesondere auf die Verzahnung zwischen Methodenentwicklung und numerischer Realisierung fokussieren. Forschung im Bereich der mathematischen Optimierung und Steuerung von Prozessen bzw. Eigenschaften, die mit Hilfe partieller Differentialgleichungen, so genannten, verteilten Systemen’, beschrieben werden, erfolgt im Kontext konkreter und exemplarischer Anwendungssituationen, die neue mathematische Herausforderungen markieren: Sicherheitsvorgaben etwa bei der Belastung von Gas- und Frischwasserleitungen oder solche für die Belastbarkeit von Verkehrsflugzeugen führen auf Druckbeschränkungen bzw.

  6. The Effect of Distributed Energy Resource Competition with Central Generation

    SciTech Connect

    Hadley, SW

    2003-12-10

    Distributed Energy Resource (DER) has been touted as a clean and efficient way to generate electricity at end-use sites, potentially allowing the exhaust heat to be put to good use as well. However, despite its environmental acceptability compared to many other types of generation, it has faced some disapproval because it may displace other, cleaner generation technologies. The end result could be more pollution than if the DER were not deployed. On the other hand, the DER may be competing against older power plants. If the DER is built then these other plants may be retired sooner, reducing their emissions. Or it may be that DER does not directly compete against either new or old plant capacity at the decision-maker level, and increased DER simply reduces the amount of time various plants operate. The key factor is what gets displaced if DER is added. For every kWh made by DER a kWh (or more with losses) of other production is not made. If enough DER is created, some power plants will get retired or not get built so not only their production but their capacity is displaced. Various characteristics of the power system in a region will influence how DER impacts the operation of the grid. The growth in demand in the region may influence whether new plants are postponed or old plants retired. The generation mix, including the fuel types, efficiencies, and emission characteristics of the plants in the region will factor into the overall competition. And public policies such as ease of new construction, emissions regulations, and fuel availability will also come into consideration.

  7. A van der Waals density functional study of adenine on graphene: Single molecular adsorption and overlayer binding

    SciTech Connect

    Berland, Kristian; Cooper, Valentino R; Langreth, David C.; Schroder, Prof. Elsebeth; Chakarova-Kack, Svetla

    2011-01-01

    The adsorption of an adenine molecule on graphene is studied using a first-principles van der Waals functional (vdW-DF) [Dion et al., Phys. Rev. Lett. 92, 246401 (2004)]. The cohesive energy of an ordered adenine overlayer is also estimated. For the adsorption of a single molecule, we determine the optimal binding configuration and adsorption energy by translating and rotating the molecule. The adsorption energy for a single molecule of adenine is found to be 711 meV, which is close to the calculated adsorption energy of the similar-sized naphthalene. Based on the single molecular binding configuration, we estimate the cohesive energy of a two-dimensional ordered overlayer. We find a significantly stronger binding energy for the ordered overlayer than for single-molecule adsorption.

  8. [Beweggründe von Krebspatienten für und gegen die Inanspruchnahme der Misteltherapie].

    PubMed

    Gschwendtner, Kathrin M; Holmberg, Christine; Weis, Joachim

    2016-01-01

    Einleitung: Die Misteltherapie ist im deutschsprachigen Raum ein häufig angewandtes komplementärmedizinisches Verfahren (KM) in der Onkologie. Diese Studie hatte das Ziel, die Beweggründe für oder gegen eine Inanspruchnahme der Misteltherapie zu untersuchen und Themenfeldern zuzuordnen. Patienten und Methoden: Es wurden qualitative leitfadengestützte Interviews mit Krebspatienten geführt. Der Interviewleitfaden fragte nach der Inanspruchnahme von KM, der Motivation zur Inanspruchnahme, Informationsverhalten und -bedürfnissen zu KM sowie nach der Krebserkrankung. Um die Beweggründe für die Inanspruchnahme oder Nichtinanspruchnahme der Misteltherapie zu verstehen, wurden die Interviews inhaltsanalytisch ausgewertet. Ergebnisse: Insgesamt wurden Interviews mit 88 Krebspatienten geführt, davon nutzen 18 (20,5%) die Misteltherapie. Die Beweggründe für oder gegen eine Inanspruchnahme der Misteltherapie ließen sich den 2 Themenfeldern «Wahrgenommene Indikation» und «Abwägungen bei der Entscheidungsfindung» zuordnen. Diskussion und Schlussfolgerungen: Mit der Misteltherapie wird sowohl ein Einfluss auf das Tumorwachstum als auch eine supportive Wirkung assoziiert. Anwender sehen die Misteltherapie als sicheres Verfahren; Nichtnutzer befürchten eher Neben- oder Wechselwirkungen. Die Empfehlung von Fachpersonal spielt eine wichtige Rolle bei der Inanspruchnahme. Zum Teil waren die Nichtnutzer interessiert an der Anwendung der Misteltherapie, befanden sich jedoch noch im Klärungsprozess. © 2016 S. Karger GmbH, Freiburg.

  9. Structure-based design and screening of inhibitors for an essential bacterial GTPase, Der.

    PubMed

    Hwang, Jihwan; Tseitin, Vladimir; Ramnarayan, Kal; Shenderovich, Mark D; Inouye, Masayori

    2012-05-01

    Der is an essential and widely conserved GTPase that assists assembly of a large ribosomal subunit in bacteria. Der associates specifically with the 50S subunit in a GTP-dependent manner and the cells depleted of Der accumulate the structurally unstable 50S subunit, which dissociates into an aberrant subunit at a lower Mg(2+) concentration. As Der is an essential and ubiquitous protein in bacteria, it may prove to be an ideal cellular target against which new antibiotics can be developed. In the present study, we describe our attempts to identify novel antibiotics specifically targeting Der GTPase. We performed the structure-based design of Der inhibitors using the X-ray crystal structure of Thermotoga maritima Der (TmDer). Virtual screening of commercially available chemical library retrieved 257 small molecules that potentially inhibit Der GTPase activity. These 257 chemicals were tested for their in vitro effects on TmDer GTPase and in vivo antibacterial activities. We identified three structurally diverse compounds, SBI-34462, -34566 and -34612, that are both biologically active against bacterial cells and putative enzymatic inhibitors of Der GTPase homologs. We also presented the possible interactions of each compound with the Der GTP-binding site to understand the mechanism of inhibition. Therefore, our lead compounds inhibiting Der GTPase provide scaffolds for the development of novel antibiotics against antibiotic-resistant pathogenic bacteria.

  10. Energy Policy Case Study - Texas: Wind, Markets, and Grid Modernization

    SciTech Connect

    Orrell, Alice C.; Homer, Juliet S.; Bender, Sadie R.; Weimar, Mark R.

    2016-09-19

    This document presents a case study of energy policies in Texas related to power system transformation, renewable energy and distributed energy resources (DERs). Texas has experienced a dramatic increase in installed wind capacity, from 116 MW in 2000 to over 15,000 MW in 2015. This achievement was enabled by the designation of Competitive Renewable Energy Zones (CREZs) and new transmission lines that transmit wind to load centers. This report highlights nascent efforts to include DERs in the ERCOT market. As costs decline and adoption rates increase, ERCOT expects distributed generation to have an increasing effect on grid operations, while bringing potentially valuable new resources to the wholesale markets.

  11. Health behaviours, socioeconomic status and diabetes incidence: the Australian Diabetes Obesity and Lifestyle Study (AusDiab).

    PubMed

    Williams, E D; Tapp, R J; Magliano, D J; Shaw, J E; Zimmet, P Z; Oldenburg, B F

    2010-12-01

    To identify the impact of socioeconomic status on incident impaired glucose metabolism and type 2 diabetes and to investigate the mediating role of health behaviours on this relationship using national, population-based data. The Australian Diabetes Obesity and Lifestyle (AusDiab) Study is a national, population-based, longitudinal study of adults aged 25 years and above. A total sample of 4,405 people provided complete baseline (1999-2000) and 5 year follow-up (2004-2005) data relevant for these analyses. Fasting plasma glucose and 2 h plasma glucose were obtained from an OGTT, and demographic, socioeconomic and behavioural data were collected by interview and questionnaire. Multinomial logistic regression examined the role of socioeconomic position in the development of diabetes and mediation analyses tested the contribution of health behaviours in this relationship. Highest level of education was a stronger predictor of incident impaired glucose tolerance and type 2 diabetes (p = 0.002), compared with household income (p = 0.103), and occupational grade (p = 0.202). Education remained a significant independent predictor of diabetes in fully adjusted models. However, the relationship was attenuated by the health behaviours (smoking and physical activity). Mediation analyses indicated that these behaviours were partial mediators (explaining 27%) of the socioeconomic status-diabetes relationship. Smoking and physical activity partly mediate the relationship between low education and type 2 diabetes. Identification of these modifiable behavioural mediators should facilitate the development of effective health promotion campaigns to target those at high risk of developing type 2 diabetes.

  12. Gender disparities in the assessment and management of cardiovascular risk in primary care: the AusHEART study.

    PubMed

    Turnbull, Fiona; Arima, Hisatomi; Heeley, Emma; Cass, Alan; Chalmers, John; Morgan, Claire; Patel, Anushka; Peiris, David; Weekes, Andrew; Anderson, Craig

    2011-06-01

    Studies indicate ongoing gender-based differences in the prevention, detection and management of cardiovascular disease. The aims of this study were to determine whether there are differences in general practitioners' (GPs') perceptions of a patient's cardiovascular risk compared with the patient's estimated risk and in the patient's subsequent medical management according to patient sex. The Australian Hypertension and Absolute Risk Study (AusHEART) was a nationally representative, cluster-stratified, cross-sectional survey among 322 GPs. Each GP was asked to collect data on cardiovascular disease risk factors and their management in 15-20 consecutive patients (age ≥55 years) who presented between April and June, 2008. They were also asked to estimate each patient's absolute risk of a cardiovascular event in the next five years. The main outcomes were the Adjusted Framingham risk, GP estimated risk and proportion of patients receiving blood pressure-lowering, statin and antiplatelet therapy. A total of 5293 patients were recruited to the study, of whom 2968 (56%) were women. Among patients without established cardiovascular disease, the level of agreement between the GP estimated risk and the Adjusted Framingham risk was poor (<50%) and was similarly so for men (kappa coefficient 0.18; 95% confidence interval (CI) 0.14-0.21) and women (0.19; 95% CI 0.16-0.22; P homogeneity = 0.57). For patients with established cardiovascular disease, however, women were more likely to be assigned by the GP to a lower risk category (66% vs. 54%, P < 0.001) and less likely to be prescribed combination (blood pressure-lowering, statin and antiplatelet) (44% vs. 56%, P < 0.001) therapy compared with men, even after adjusting for patient age. Cardiovascular risk is underrecognized and undertreated in Australian primary care patients, with women apparently disproportionately affected. These findings underscore the importance of initiatives to raise awareness of

  13. Validity of a multi-context sitting questionnaire across demographically diverse population groups: AusDiab3.

    PubMed

    Clark, Bronwyn K; Lynch, Brigid M; Winkler, Elisabeth Ah; Gardiner, Paul A; Healy, Genevieve N; Dunstan, David W; Owen, Neville

    2015-12-04

    Sitting time questionnaires have largely been validated in small convenience samples. The validity of this multi-context sitting questionnaire against an accurate measure of sitting time is reported in a large demographically diverse sample allowing assessment of validity in varied demographic subgroups. A subgroup of participants of the third wave of the Australian Diabetes, Obesity, and Lifestyle (AusDiab3) study wore activPAL3™ monitors (7 days, 24 hours/day protocol) and reported their sitting time for work, travel, television viewing, leisure computer use and "other" purposes, on weekdays and weekend days (n = 700, age 36-89 years, 45% men). Correlations (Pearson's r; Spearman's ρ) of the self-report measures (the composite total, contextual measures and items) with monitor-assessed sitting time were assessed in the whole sample and separately in socio-demographic subgroups. Agreement was assessed using Bland-Altman plots. The composite total had a correlation with monitor-assessed sitting time of r = 0.46 (95% confidence interval [CI]: 0.40, 0.52); this correlation did not vary significantly between demographic subgroups (all >0.4). The contextual measure most strongly correlated with monitor-assessed sitting time was work (ρ = 0.25, 95 % CI: 0.17, 0.31), followed by television viewing (ρ = 0.16, 95 % CI: 0.09, 0.24). Agreement of the composite total with monitored sitting time was poor, with a positive bias (B = 0.53, SE 0.04, p < 0.001) and wide limits of agreement (±4.32 h). This multi-context questionnaire provides a total sitting time measure that ranks participants well for the purposes of assessing health associations but has limited accuracy relative to activPAL-assessed sitting time. Findings did not differ in demographic subgroups.

  14. GridAgents DER Testing: Cooperative Research and Development Final Report, CRADA Number CRD-08-265

    SciTech Connect

    Harrison, K.

    2012-04-01

    The project objectives are to perform research, development, and pilot-scale testing of advanced, next-generation distribution operational strategies using ConEdison's 3G: Distribution System of the Future and associated infrastructure for the real-world Test Bed (demonstration network) combined with the Infotility GridAgents: Secure Agent Framework for Energy as the software platform for advanced operational strategies development. The objective is to accelerate high-payoff technologies that, because of their risk, are unlikely to be developed in a timely manner without a partnership between industry and the Federal government. NREL will be responsible for the evaluation of equipment design and control methods for DER integration and testing of prototype DER technologies and control equipment at the NREL test facility.

  15. Distributed Energy Systems Integration and Demand Optimization for Autonomous Operations and Electric Grid Transactions

    SciTech Connect

    Ghatikar, Girish; Mashayekh, Salman; Stadler, Michael; Yin, Rongxin; Liu, Zhenhua

    2015-11-29

    Distributed power systems in the U.S. and globally are evolving to provide reliable and clean energy to consumers. In California, existing regulations require significant increases in renewable generation, as well as identification of customer-side distributed energy resources (DER) controls, communication technologies, and standards for interconnection with the electric grid systems. As DER deployment expands, customer-side DER control and optimization will be critical for system flexibility and demand response (DR) participation, which improves the economic viability of DER systems. Current DER systems integration and communication challenges include leveraging the existing DER and DR technology and systems infrastructure, and enabling optimized cost, energy and carbon choices for customers to deploy interoperable grid transactions and renewable energy systems at scale. Our paper presents a cost-effective solution to these challenges by exploring communication technologies and information models for DER system integration and interoperability. This system uses open standards and optimization models for resource planning based on dynamic-pricing notifications and autonomous operations within various domains of the smart grid energy system. It identifies architectures and customer engagement strategies in dynamic DR pricing transactions to generate feedback information models for load flexibility, load profiles, and participation schedules. The models are tested at a real site in California—Fort Hunter Liggett (FHL). Furthermore, our results for FHL show that the model fits within the existing and new DR business models and networked systems for transactive energy concepts. Integrated energy systems, communication networks, and modeling tools that coordinate supply-side networks and DER will enable electric grid system operators to use DER for grid transactions in an integrated system.

  16. Van der Waals corrected DFT study of adsorption of groups VA and VIA hydrides on graphene monoxide

    NASA Astrophysics Data System (ADS)

    Notash, M. Yaghoobi; Ebrahimzadeh, A. Rastkar

    2016-06-01

    Adsorption properties of H2O, H2S, NH3 and PH3 on graphene monoxide (GMO) nano flack are investigated using density functional theory (DFT). Calculations were carried out by van der Waals correction and general gradient approximation. The adsorption energies and charge transfer between species are obtained and discussed for the considered positions of adsorbate molecules. Charge transfer analysis show that the gas molecules act as an electron acceptor in all cases. The analysis of the adsorption energies suggest GMO can be a good candidate for the adsorption of these molecules.

  17. Kommunale Energieversorger als wesentliche Akteure der Digitalisierung - Strategien und Handlungsoptionen

    NASA Astrophysics Data System (ADS)

    Reiche, Katherina

    Die Digitalisierung erfasst sämtliche Bereiche des Lebens und Wirtschaftens. Auch die Kommunalwirtschaft - insbesondere die kommunale Energiewirtschaft - sieht sich perspektivisch disruptiven Entwicklungen gegenüber. Stadtwerke haben bereits viele Herausforderungen erfolgreich gemeistert und stehen auch der Digitalisierung positiv gegenüber. Vielerorts gestalten kommunale Unternehmen den digitalen Wandel bereits aktiv mit. Dieser Artikel arbeitet die Assets kommunaler Unternehmen heraus und zeigt Strategien und Handlungsoptionen zum Umgang mit der digitalen Transformation für kommunale Energieversorgungsunternehmen auf. Dabei zeigt sich, dass das politische und regulatorische Umfeld für das positive Gelingen der Digitalisierung entscheidend sind. Kommunale Unternehmen benötigen die gleichen Marktzugangsbedingungen wie andere Akteure. Ferner profitieren kommunale Unternehmen von einigen Wettbewerbsvorteilen, etwa hohen Vertrauenswerten ihrer Kunden und umfangreiches Know-how im Datenmanagement.

  18. A cartography of the van der Waals territories.

    PubMed

    Alvarez, Santiago

    2013-06-28

    The distribution of distances from atoms of a particular element E to a probe atom X (oxygen in most cases), both bonded and intermolecular non-bonded contacts, has been analyzed. In general, the distribution is characterized by a maximum at short E···X distances corresponding to chemical bonds, followed by a range of unpopulated distances--the van der Waals gap--and a second maximum at longer distances--the van der Waals peak--superimposed on a random distribution function that roughly follows a d(3) dependence. The analysis of more than five million interatomic "non-bonded" distances has led to the proposal of a consistent set of van der Waals radii for most naturally occurring elements, and its applicability to other element pairs has been tested for a set of more than three million data, all of them compared to over one million bond distances.

  19. Der Körper der Craniota und die Differenzierung seiner Grundgestalt

    NASA Astrophysics Data System (ADS)

    Rieger, Reinhard; Maier, Wolfgang; Goldschmid, Alfred; Westheide, Wilfried

    Die rezenten Wirbeltiere — die wir nun auf Grund ihres wichtigsten Schlüsselmerkmals generell Cranioten oder Schädeltiere nennen sollten (s. a. S. 5) — umfassen nah ezu 50.000 Arten. Nach allgemeinen Schätzungen sind dies etwa 1% der Tiere dieses Taxons, die jemals existierten. Bis heute wurden mehrere zehntausend fossiler Arten nachgewiesen, und ständig kommen neue Fossilfunde hinzu. Die ältesten eindeutig als Craniota anzusprechenden Fossilfunde haben ein Alter von etwa 545 Mio. Jahren (S. 187). Paläontologie und Paläobiologie rekonstruierten eingehend Aussehen und Lebensweise vieler dieser ausgestorbenen Arten. Viele Verwandtschaftsbeziehungen zwischen den rezenten Wirbeltiertaxa werden nur unter Berücksichtigung dieser Fossilformen verständlich.

  20. Spontaneous doping on high quality talc-graphene-hBN van der Waals heterostructures

    NASA Astrophysics Data System (ADS)

    Mania, E.; Alencar, A. B.; Cadore, A. R.; Carvalho, B. R.; Watanabe, K.; Taniguchi, T.; Neves, B. R. A.; Chacham, H.; Campos, L. C.

    2017-09-01

    Steady doping, added to its remarkable electronic properties, would make graphene a valuable commodity in the solar cell market, as energy power conversion could be substantially increased. Here we report a graphene van der Waals heterostructure which is able to spontaneously dope graphene (p-type) up to n ~ 2.2  ×  1013 cm-2 while providing excellent charge mobility (μ ~ 25 000 cm2 V-1 s-1). Such properties are achieved via deposition of graphene on atomically flat layered talc, a natural and abundant dielectric crystal. Raman investigation shows a preferential charge accumulation on graphene-talc van der Waals heterostructures, which are investigated through the electronic properties of talc/graphene/hBN heterostructure devices. These heterostructures preserve graphene’s good electronic quality, verified by the observation of quantum Hall effect at low magnetic fields (B  =  0.4 T) at T  =  4.2 K. In order to investigate the physical mechanisms behind graphene-on-talc p-type doping, we performed first-principles calculations of their interface structural and electronic properties. In addition to potentially improving solar cell efficiency, graphene doping via van der Waals stacking is also a promising route towards controlling the band gap opening in bilayer graphene, promoting a steady n or p type doping in graphene and, eventually, providing a new path to access superconducting states in graphene, predicted to exist only at very high doping.

  1. Local Probe Spectroscopy of Two-Dimensional van der Waals Heterostructures

    NASA Astrophysics Data System (ADS)

    Yankowitz, Matthew Abraham

    A large family of materials, collectively known as "van der Waals materials", have attracted enormous research attention over the past decade following the realization that they could be isolated into individual crystalline monolayers, with charge carriers behaving effectively two-dimensionally. More recently, an even larger class of composite materials has been realized, made possible by combining the isolated atomic layers of different materials into "van der Waals heterostructures", which can exhibit electronic and optical behaviors not observed in the parent materials alone. This thesis describes efforts to characterize the atomic-scale structural and electronic properties of these van der Waals materials and heterostructures through scanning tunneling microscopy measurements. The majority of this work addresses the properties of monolayer and few-layer graphene, whose charge carriers are described by massless and massive chiral Dirac Hamiltonians, respectively. In heterostructures with hexagonal boron nitride, an insulating isomorph of graphene, we observe electronic interference patterns between the two materials which depend on their relative rotation. As a result, replica Dirac cones are formed in the valence and conduction bands of graphene, with their energy tuned by the rotation. Further, we are able to dynamically drag the graphene lattice in these heterostructures, owing to an interaction between the scanning probe tip and the domain walls formed by the electronic interference pattern. Similar dragging is observed in domain walls of trilayer graphene, whose electronic properties are found to depend on the stacking configuration of the three layers. Scanning tunneling spectroscopy provides a direct method for visualizing the scattering pathways of electrons in these materials. By analyzing the scattering, we can directly infer properties of the band structures and local environments of these heterostructures. In bilayer graphene, we map the electrically

  2. Thermodynamic properties of van der Waals fluids from Monte Carlo simulations and perturbative Monte Carlo theory.

    PubMed

    Díez, A; Largo, J; Solana, J R

    2006-08-21

    Computer simulations have been performed for fluids with van der Waals potential, that is, hard spheres with attractive inverse power tails, to determine the equation of state and the excess energy. On the other hand, the first- and second-order perturbative contributions to the energy and the zero- and first-order perturbative contributions to the compressibility factor have been determined too from Monte Carlo simulations performed on the reference hard-sphere system. The aim was to test the reliability of this "exact" perturbation theory. It has been found that the results obtained from the Monte Carlo perturbation theory for these two thermodynamic properties agree well with the direct Monte Carlo simulations. Moreover, it has been found that results from the Barker-Henderson [J. Chem. Phys. 47, 2856 (1967)] perturbation theory are in good agreement with those from the exact perturbation theory.

  3. The RgI2 (ion-pair states) van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Baturo, Vera V.; Lukashov, Sergey S.; Poretsky, Sergey A.; Pravilov, Anatoly M.

    2017-09-01

    This paper is an overview of our recent experimental investigations of the RgI2 van der Waals complexes, Rg = He, Ar, Kr, performed by means of laser induced fluorescence spectroscopy, optical-optical double resonance and supersonic molecular beam techniques. Spectroscopic parameters of these complexes in the E0 g + ion-pair state, such as binding energies and several spectroscopic constants, have been determined. Most likely, the potential energy surfaces of the all RgI2( E) complexes under study present T-shaped minima. Vibrational and electronic predissociations of the RgI2( E) complexes were analyzed. Relative contributions of the different electronic predissociation channels and vibrational distributions of the decay products were determined. Possible mechanisms of the complexes decay are suggested and discussed.

  4. The Economics of van der Waals Force Engineering

    NASA Astrophysics Data System (ADS)

    Pinto, Fabrizio

    2008-01-01

    As micro-electro-mechanical system (MEMS) fabrication continues on an ever-decreasing scale, new technological challenges must be successfully negotiated if Moore's Law is to be an even approximately valid model of the future of device miniaturization. Among the most significant obstacles is the existence of strong surface forces related to quantum mechanical van der Waals interatomic interactions, which rapidly diverge as the distance between any two neutral boundaries decreases. The van der Waals force is a contributing factor in several device failures and limitations, including, for instance, stiction and oscillator non-linearities. In the last decade, however, it has been conclusively shown that van der Waals forces are not just a MEMS limitation but can be engineered in both magnitude and sign so as to enable classes of proprietary inventions which either deliver novel capabilities or improve upon existing ones. The evolution of van der Waals force research from an almost exclusively theoretical field in quantum-electro-dynamics to an enabling nanotechnology discipline represents a useful example of the ongoing paradigm shift from government-centered to private-capital funded R&D in cutting-edge physics leading to potentially profitable products. In this paper, we discuss the reasons van der Waals force engineering may lead to the creation of thriving markets both in the short and medium terms by highlighting technical challenges that can be competitively addressed by this novel approach. We also discuss some notable obstacles to the cultural transformation of the academic research community required for the emergence of a functional van der Waals force engineering industry worldwide.

  5. Von der Kulturkunde zur Landeskunde: Geschichte und Probleme eines Aspekts des Fremdsprachenunterrichts aus deutscher Sicht (From Culture to Country: History and Problems of an Aspect of Foreign Language Teaching from a German Point of View)

    ERIC Educational Resources Information Center

    Gutschow, Harald

    1977-01-01

    Currently some skepticism exists concerning the value of area studies--especially the concept of "national traits." Also, the alleged motivational value may be offset by the sacrifice of language-learning time. German language teaching has followed the U.S. lead; American teachers might profit from German experience. (Text is in German.) (WGA)

  6. "Onkle Karl" aus Milwaukee: Deutsch-amerikanische Einwandererkultur im Spiegel der Jugendliteratur vor hundert Jahren (Uncle Carl from Milwaukee: German-American Newcomer Culture Reflected in Children's Literature a Hundred Years Ago).

    ERIC Educational Resources Information Center

    Weiss, Gerhard

    1998-01-01

    Examines a late nineteenth-century Milwaukee (Wisconsin) publication for children and young people as a reflection of German-American middle-class culture of the time, showing how the spirit of the 1848 revolution and the experience of the American Civil War shaped German-American intellectuals and how the ideals of freedom and equality dominated…

  7. Dreissig Jahre Volksrepublik Polen. Aus den Thesen des Zentralkomitees der Polnischen Vereinigten Arbeiterpartei (Thirty years of the People's Republic of Poland. From the Theses of the Central Committee of the Polish United Workers' Party)

    ERIC Educational Resources Information Center

    Fremdsprachenunterricht, 1974

    1974-01-01

    Offers an overview of the development of the teaching of Russian in the People's Republic of Poland since its introduction in 1945 and the support of the periodical "Jezyk Rosyjski" (Russian Language) in the attainment of the goals set by the Ministry of Popular Education of the People's Republic of Poland. (Text is in German.) (IFS/WGA)

  8. Bericht aus der Praxis/Practice Report: How to successfully establish PAL in medical education. 10 tips to succeed in PAL-based courses in undergraduate medical education (UGME).

    PubMed

    Hofer, Matthias; Klein, Kathrin; Malzkorn, Bastian; Martin, Alice; Weigel, Christian; Martin, Ole

    2017-08-01

    This article aims to provide useful suggestions for the implementation of new courses with peer-assisted learning (PAL) in undergraduate medical education (UGME). It presents 10 key tips for needs assessment, clarification of goals and objectives for internal marketing, the choice of teaching formats, fund raising, recruiting of educators, qualification of peer tutors, the fun factor, how to establish a structured and longitudinal curriculum, assessment methods and motivation, collecting feedback and the use of its results. These 10 tips are linked to scientific evidence in the educational literature and elucidated by specific examples, based upon a major PAL project on diagnostic imaging, which can be transferred to other teaching topics as well. In conclusion, the described tips represent a helpful tool to avoid common pitfalls in the planning, implementation, evaluation and quality-assurance of PAL-based educational projects. Copyright © 2017. Published by Elsevier GmbH.

  9. "Onkle Karl" aus Milwaukee: Deutsch-amerikanische Einwandererkultur im Spiegel der Jugendliteratur vor hundert Jahren (Uncle Carl from Milwaukee: German-American Newcomer Culture Reflected in Children's Literature a Hundred Years Ago).

    ERIC Educational Resources Information Center

    Weiss, Gerhard

    1998-01-01

    Examines a late nineteenth-century Milwaukee (Wisconsin) publication for children and young people as a reflection of German-American middle-class culture of the time, showing how the spirit of the 1848 revolution and the experience of the American Civil War shaped German-American intellectuals and how the ideals of freedom and equality dominated…

  10. Curves of growth for van der Waals broadened spectral lines

    NASA Technical Reports Server (NTRS)

    Park, C.

    1980-01-01

    Curves of growth are evaluated for a spectral line broadened by the van der Waals interactions during collisions. The growth of the equivalent widths of such lines is shown to be dependent on the product of the perturber density and the 6/10 power of the van der Waals potential coefficient. When the parameter is small, the widths grow as the 1/2 power of the optical depth as they do for the Voigt profile: but when the parameter is large, they grow as 2/3 power and, hence, faster than the Voigt profile. An approximate analytical expression for the computed growth characteristics is given.

  11. Description of van der Waals interactions using transformation optics.

    PubMed

    Zhao, Rongkuo; Luo, Yu; Fernández-Domínguez, A I; Pendry, J B

    2013-07-19

    Exact calculation of the van der Waals interaction between closely spaced plasmonic nanoparticles is challenging due to the strong concentration of the electromagnetic fields that takes place at the nanometric gap between them. The technique of transformation optics, capable of mapping a small volume into any desired length scale, enables us to shed physical insight into the intricate behavior of electromagnetic fields in extremely small gaps. Using this theoretical tool, we obtain universal analytical expressions for the van der Waals interactions between spherical nanoparticles made of realistic metals at arbitrary separation.

  12. Einsteins Traum. Expeditionen an die Grenzen der Raumzeit.

    NASA Astrophysics Data System (ADS)

    Hawking, S. W.

    This book is a German translation, by H. Kober, of the English original "Black holes and baby universes and other essays" published in 1993. It is a collection of articles written by the author between 1976 and 1992. Contents: 1. Kindheit. 2. Oxford und Cambridge. 3. Meine Erfahrung mit ALS. 4. Öffentliche Einstellungen zur Wissenschaft. 5. Eine kurze Geschichte der Kurzen Geschichte. 6. Mein Standpunkt. 7. Einsteins Traum. 8. Der Ursprung des Universums. 9. Die Quantenmechanik Schwarzer Löcher. 10. Schwarze Löcher und Baby-Universen. 11. Ist alles vorherbestimmt? 12. Die Zukunft des Universums. 13. Desert Island Discs, ein Interview.

  13. Aufbau und Anpassung der Motorsteuerungs-Software für Otto- und Dieselmotoren

    NASA Astrophysics Data System (ADS)

    Stuhler, Harald; Ricken, Volker; Diener, René

    Die Erfüllung steigender Kundenansprüche und strenger gesetzlicher Vorgaben hinsichtlich der Verringerung des Kraftstoffverbrauchs, der Reduzierung von Schadstoffemissionen, der Erhöhung von Fahrsicherheit, Fahrleistung und Fahrkomfort ist untrennbar mit dem Einzug elektronischer Systeme in moderne Kraftfahrzeuge verbunden. Die elektronischen Systeme bestimmen zunehmend den Kundennutzen und werden für die Differenzierung der Automobilhersteller untereinander immer wichtiger. Daher sind sie ein wesentlicher Erfolgsfaktor moderner Kraftfahrzeuge.

  14. EPITOPE-BASED VACCINE FOR THE TREATMENT OF DER F 3 ALLERGY.

    PubMed

    Zhan, Xiaodong; Li, Chaopin; Jiang, Yuxing; Li, Na

    2015-12-01

    mites allergic asthma is caused by exposure to home dust mite (HDM). Der f 3 is believed to be one of the major allergens in mites allergic asthma. The work was to identify the immune characteristics of Der f 3 epitope-based vaccine containing T cell and B cell epitopes. T cell lines were generated from peripheral blood mononuclear cells of Der f 3 allergic patients. Three T cell epitopes and five B cell epitopes of Der f 3, which we identified previously, were selected to design a polypeptide (named Der f3-peptides). DNA constructions encoding these Der f 3-peptides were expressed in Escherichia coli. The T cell lines were stimulated with the peptides and tested for proliferative capacity and cytokine production. plasmid pET28a (+)-Der f 3-peptides was constructed and expressed in E. coli BL21, and the Der f3-peptides protein was purified and confirmed by Western blotting. The Der f 3-peptides were recognized by the T cell clones from allergic patients. SI value of Der f 3 group and Der f 3-peptides group were both higher than that of PBS group (P<0.05). The Der f 3 and Der f 3 peptides induced secretions of IL-4 and IL-5 were decreased compared with that of PBS group (P<0.05). The capacity of IgE-binding to Der f 3-peptides (41.25±5.67) μg/ml was decreased dramatically compared with that of Der f 3 (83.60 ± 10.92) μg/ml (P < 0.05). our results demonstrate that several major T cell epitopes and B cell epitopes of Der f 3 can be valuable for designing the peptide-based immunotherapeutics for the mites allergic asthma. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  15. Der f 35: An MD-2-like house dust mite allergen that cross-reacts with Der f 2 and Pso o 2.

    PubMed

    Fujimura, T; Aki, T; Isobe, T; Matsuoka, A; Hayashi, T; Ono, K; Kawamoto, S

    2017-04-25

    Dermatophagoides farinae is a source of airborne house dust mite (HDM) allergens. We elucidated IgE-reactive allergens from D. farinae by two-dimensional immunoblotting-based allergenome analysis, and identified one new allergen, named Der f 35, that possesses IgE-binding capacity comparable to that of Der f 2. The aim of this study was to clarify the allergenic capacity of new HDM allergen Der f 35. We cloned der f 35 from D. farinae mRNA and produced recombinant Der f 35 in Escherichia coli. The IgE-binding capacity of Der f 35 and its cross-reactivity with group 2 allergens from D. farinae and Psoroptes ovis were determined by enzyme-linked immunosorbent assay (ELISA) and ELISA inhibition assays, respectively. The deduced amino acid sequence for der f 35, which possesses the MD-2-related lipid-recognition domain, showed higher identity with group 2 allergens from P. ovis (61.5%) and Blomia tropicalis (50.7%) than with Der f 2 (40.8%). Der f 35 showed IgE-binding frequencies of 77.5% (31/40) for the native form upon allergenome analysis and 51.4% (18/35) for recombinant structure by ELISA. Der f 35 showed cross-reactivity with Der f 2 and Pso o 2 in reaction with HDM-allergic patients' IgE by ELISA inhibition assay. Der f 35 is a candidate major allergen from D. farinae, which is more similar to group 2 allergens from sheep scab mite and storage mites. Der f 35 could be responsible for the cross-reactivity among group 2 mite allergens. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  16. IgE Abs to Der p 1 and Der p 2 as diagnostic markers of house dust mite allergy as defined by a bronchoprovocation test.

    PubMed

    Minami, Takafumi; Fukutomi, Yuma; Lidholm, Jonas; Yasueda, Hiroshi; Saito, Akemi; Sekiya, Kiyoshi; Tsuburai, Takahiro; Maeda, Yuji; Mori, Akio; Taniguchi, Masami; Hasegawa, Maki; Akiyama, Kazuo

    2015-01-01

    Limited information is available regarding the clinical usefulness of measuring the levels of IgE to allergen components from house dust mites (HDMs) in the diagnosis of genuine HDM allergy. To evaluate the diagnostic usefulness of measuring levels of serum IgE antibodies (Abs) to allergen components from Dermatophagoides pteronyssinus (DP) as a predictor of immediate asthmatic response (IAR) to bronchoprovocation, we studied 55 DP-sensitized asthmatic patients who underwent a bronchoprovocation test using crude DP extract. The levels of IgE Abs to crude DP, nDer p 1, rDer p 2, and rDer p 10 in patients who showed IAR (n = 41) were compared with those in patients who showed no IAR (n = 14). While the frequencies of positivity for IgE Abs to nDer p 1 and rDer p 2 among the entire study population were 89 and 86%, respectively, all patients with IAR tested positive for both of them with high IgE concentrations. The areas under the receiver operating characteristic curves for IgE to nDer p 1 and rDer p 2 as predictors of IAR were 0.913 and 0.906, respectively. The specificity of IgE to nDer p 1 and rDer p 2 was higher than IgE to crude DP even at low cut-off points. IgE to nDer p 1 and/or rDer p 2 was highly predictive of allergen-induced IAR. These findings validate the clinical usefulness of measuring the levels of IgE to nDer p 1 and rDer p 2 as a diagnostic tool for genuine HDM allergy. Copyright © 2014 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

  17. Charakterisierung von Sulfotransferasen im Gastrointestinaltrakt von Mensch und Ratte und Aktivierung von Promutagenen in V79-Zellen, die eine intestinale Form (1B1) des Menschen und der Ratte exprimieren

    NASA Astrophysics Data System (ADS)

    Teubner, Wera

    2001-05-01

    Die Ausstattung der gastrointestinalen Mukosa des Menschen und der Ratte mit Sulfotransferasen wurde mit Hilfe von Immunodetektion und Enzymaktivitätsmessungen untersucht. In Proben aus Colon und Rektum von 39 Personen wurden die Formen h1A1, h1A3 und h1B1 identifiziert, wobei in einer weiteren Probe, die als einzige von einem an Colitis Ulcerosa erkrankten Patienten stammte, keine Sulfotransferasen nachgewiesen werden konnten. Bei der Immunblot-Analyse war das Expressionsmuster der einzelnen Formen in allen Proben ähnlich. In wenigen Proben waren die relativen Signalintensitäten der h1A1 und der h1B1 um die Hälfte erniedrigt. Der Gehalt von SULT an zytosolischem Protein zeigte einen bis zu 8 - 10fachen Unterschied, er betrug jedoch bei zwei Dritteln der Proben zwischen 0,15 und 0,3 (h1A1 und h1A3) bzw. 0,6 und 0,8 Promille (h1B1). Die Variation konnte nicht auf Alter, Geschlecht oder Krankheitsbild der Patienten zurückgeführt werden. Auch der für die allelischen Varianten der h1A1 beschriebene Effekt auf die Enzymaktiviät bzw. Stabilität konnte in der Menge an immunreaktivem Protein nicht in diesem Ausma detektiert werden. Die Allelhäufigkeit von h1A1*R und h1A1*H war gegenüber der gesunden Bevölkerung nicht verändert. In den sieben Proben aus dem Dünndarm (Coecum, viermal Ileum, Jejunum) konnten zusätzlich die Formen h1E1 und h2A1 identifiziert werden. Ein möglicherweise der Form h1C1 entsprechendes Protein wurde im Magen detektiert. Im Vergleich zum Menschen war die Expression in der Ratte stärker auf die Leber konzentriert. Während beim Menschen in allen untersuchten Abschnitten Sulfotransferasen in Mengen detektiert wurden, die in zwei Fällen (h1B1 und h1A3) sogar den Gehalt in der Leber überstiegen, beschränkte sich die Expression in der Ratte auf im Vergleich zur Leber geringe Mengen im Magen und Dickdarm. Nachgewiesen wurden die r1B1, r1A1 sowie eine nicht identifizierte Form von 35kD, bei der es sich vermutlich um die r1C2 handelt. Im

  18. Web-gestütztes Social Networking am Beispiel der Plattform Wissensmanagement"

    NASA Astrophysics Data System (ADS)

    Lindstaedt, Stefanie; Thurner, Claudia

    Anhand der Plattform Wissensmanagement, der größten deutschsprachigen Community im Themenfeld Wissensmanagement, werden organisationale Rahmenbedingungen, technische Werkzeuge und Rollen der Moderatorin diskutiert, die Bedingungen für den erfolgreichen Betrieb einer Community im Web 2.0 sind. Weiters wird dargestellt, wie Communities für das betriebliche Wissensmanagement eingesetzt werden können.

  19. Geschichte der geodätischen Instrumente und Verfahren im Altertumund Mittelalter.

    NASA Astrophysics Data System (ADS)

    Schmidt, F.

    Contents:A. Einleitung und allgemeiner Teil.B. Besonderer Teil:1. Nivellierinstrumente. 2. Instrumente zum Antragen eines rechten Winkels. 3. Längenmesser. 4. Stäbe und Stabzusammensetzungen als Instrumente zurmittelbaren Streckenbestimmung. 5. Die Instrumente mit dem Schattenquadrat: Das geometrische Quadrat. Das Astrolab. Der Quadrant. Anwendungen der Instrumente mit dem Schattenquadrat. 6. Der Jakobsstab. 7. Triangulationsinstrumente. 8. Schmiegen.

  20. Communication: THz absorption spectrum of the CO2-H2O complex: Observation and assignment of intermolecular van der Waals vibrations

    NASA Astrophysics Data System (ADS)

    Andersen, J.; Heimdal, J.; Mahler, D. W.; Nelander, B.; Larsen, R. Wugt

    2014-03-01

    Terahertz absorption spectra have been recorded for the weakly bound CO2-H2O complex embedded in cryogenic neon matrices at 2.8 K. The three high-frequency van der Waals vibrational transitions associated with out-of-plane wagging, in-plane rocking, and torsional motion of the isotopic H2O subunit have been assigned and provide crucial observables for benchmark theoretical descriptions of this systems' flat intermolecular potential energy surface. A (semi)-empirical value for the zero-point energy of 273 ± 15 cm-1 from the class of intermolecular van der Waals vibrations is proposed and the combination with high-level quantum chemical calculations provides a value of 726 ± 15 cm-1 for the dissociation energy D0.

  1. Communication: THz absorption spectrum of the CO2-H2O complex: observation and assignment of intermolecular van der Waals vibrations.

    PubMed

    Andersen, J; Heimdal, J; Mahler, D W; Nelander, B; Larsen, R Wugt

    2014-03-07

    Terahertz absorption spectra have been recorded for the weakly bound CO2-H2O complex embedded in cryogenic neon matrices at 2.8 K. The three high-frequency van der Waals vibrational transitions associated with out-of-plane wagging, in-plane rocking, and torsional motion of the isotopic H2O subunit have been assigned and provide crucial observables for benchmark theoretical descriptions of this systems' flat intermolecular potential energy surface. A (semi)-empirical value for the zero-point energy of 273 ± 15 cm(-1) from the class of intermolecular van der Waals vibrations is proposed and the combination with high-level quantum chemical calculations provides a value of 726 ± 15 cm(-1) for the dissociation energy D0.

  2. Nonlocal van der Waals functionals: The case of rare-gas dimers and solids

    NASA Astrophysics Data System (ADS)

    Tran, Fabien; Hutter, Jürg

    2013-05-01

    Recently, the nonlocal van der Waals (vdW) density functionals [M. Dion, H. Rydberg, E. Schröder, D. C. Langreth, and B. I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004), 10.1103/PhysRevLett.92.246401] have attracted considerable attention due to their good performance for systems where weak interactions are important. Since the physics of dispersion is included in these functionals, they are usually more accurate and show less erratic behavior than the semilocal and hybrid methods. In this work, several variants of the vdW functionals have been tested on rare-gas dimers (from He2 to Kr2) and solids (Ne, Ar, and Kr) and their accuracy compared to standard semilocal approximations, supplemented or not by an atom-pairwise dispersion correction [S. Grimme, J. Antony, S. Ehrlich, and H. Krieg, J. Chem. Phys. 132, 154104 (2010), 10.1063/1.3382344]. An analysis of the results in terms of energy decomposition is also provided.

  3. Imaging of Interlayer Coupling in van der Waals Heterostructures Using a Bright-Field Optical Microscope.

    PubMed

    Alexeev, Evgeny M; Catanzaro, Alessandro; Skrypka, Oleksandr V; Nayak, Pramoda K; Ahn, Seongjoon; Pak, Sangyeon; Lee, Juwon; Sohn, Jung Inn; Novoselov, Kostya S; Shin, Hyeon Suk; Tartakovskii, Alexander I

    2017-09-13

    Vertically stacked atomic layers from different layered crystals can be held together by van der Waals forces, which can be used for building novel heterostructures, offering a platform for developing a new generation of atomically thin, transparent, and flexible devices. The performance of these devices is critically dependent on the layer thickness and the interlayer electronic coupling, influencing the hybridization of the electronic states as well as charge and energy transfer between the layers. The electronic coupling is affected by the relative orientation of the layers as well as by the cleanliness of their interfaces. Here, we demonstrate an efficient method for monitoring interlayer coupling in heterostructures made from transition metal dichalcogenides using photoluminescence imaging in a bright-field optical microscope. The color and brightness in such images are used here to identify mono- and few-layer crystals and to track changes in the interlayer coupling and the emergence of interlayer excitons after thermal annealing in heterobilayers composed of mechanically exfoliated flakes and as a function of the twist angle in atomic layers grown by chemical vapor deposition. Material and crystal thickness sensitivity of the presented imaging technique makes it a powerful tool for characterization of van der Waals heterostructures assembled by a wide variety of methods, using combinations of materials obtained through mechanical or chemical exfoliation and crystal growth.

  4. Thermal electron attachment to van der Waals molecules containing O2

    NASA Astrophysics Data System (ADS)

    Huo, Winifred M.; Fessenden, Richard W.; Bauschlicher, Charles W., Jr.

    1984-12-01

    Calculations on O2ṡN2 and O-2ṡN2 have been carried out to explain the large enhancement in the attachment rate of thermal electrons found in van der Waals molecules containing O2. Two geometries, T-shape and linear, are used. SCF wave functions are used to represent both the neutral molecule and the ion. The incoming electron is approximated by a plane wave. The width is determined using a shielded polarization potential. The effect of additional vibrational structures of the van der Waals molecule on the attachment process is investigated by studying the O2-N2 stretching mode using Lennard-Jones potentials. Symmetry breaking, which allows the molecule to attach a p wave electron, is shown to play a primary role. The lowering of resonance energy, due to a deeper Lennard-Jones potential of O-2ṡN2 in comparison with O2ṡN2, furthers the enhancement. The calculated attachment rate is comparable to that determined by Shimamori and Fessenden, but differs from the recent values obtained by Toriumi and Hatano, who used a different set of reactions to interpret their data.

  5. van der Waals Solids from Self-Assembled Nanoscale Building Blocks.

    PubMed

    Choi, Bonnie; Yu, Jaeeun; Paley, Daniel W; Trinh, M Tuan; Paley, Maria V; Karch, Jessica M; Crowther, Andrew C; Lee, Chul-Ho; Lalancette, Roger A; Zhu, Xiaoyang; Kim, Philip; Steigerwald, Michael L; Nuckolls, Colin; Roy, Xavier

    2016-02-10

    Traditional atomic van der Waals materials such as graphene, hexagonal boron-nitride, and transition metal dichalcogenides have received widespread attention due to the wealth of unusual physical and chemical behaviors that arise when charges, spins, and vibrations are confined to a plane. Though not as widespread as their atomic counterparts, molecule-based two-dimensional (2D) layered solids offer significant benefits; their structural flexibility will enable the development of materials with tunable properties. Here we describe a layered van der Waals solid self-assembled from a structure-directing building block and C60 fullerene. The resulting crystalline solid contains a corrugated monolayer of neutral fullerenes and can be mechanically exfoliated. The absorption spectrum of the bulk solid shows an optical gap of 390 ± 40 meV that is consistent with thermal activation energy obtained from electrical transport measurement. We find that the dimensional confinement of fullerenes significantly modulates the optical and electronic properties compared to the bulk solid.

  6. Biologische Wirkungen der Bestrahlung mit schweren Ionen

    NASA Astrophysics Data System (ADS)

    Kiefer, Jürgen

    1982-06-01

    Experiments with accelerated heavy ions may contribute to the understanding of biological radiation action. After outlining the theoretical background experiments are described which were carried out at the UNILAC-machine (Gesellschaft für Schwerionenforschung, Darmstadt, Germany) where ions up to uranium can be accelerated to maximal specific energies of 10 MeV/u. Yeast cells served as biological test systems with the synthesis of ribosomal RNA (r-RNA), colony-forming ability and mutation induction as experimental endpoints. A relationship between action and energy deposition by individual particles can be demonstrated for the inhibition of r-RNA synthesis, in other cases the ion energy plays also an important role indicating that the interaction of δ-electrons from different particles contributes significantly to the biological effect.

  7. AusEinetter, 1998.

    ERIC Educational Resources Information Center

    AusEinetter, 1998

    1998-01-01

    This publication contains the 1998 issues of the Australian Early Intervention Network for Mental Health in Young People newsletters for health professionals. The newsletters disseminate information about the national and local initiatives for intervention and prevention of mental health problems in young children and youth. Each issue also offers…

  8. AusEinetter, 1999.

    ERIC Educational Resources Information Center

    AusEinetter, 1999

    1999-01-01

    This document contains issues eight and nine of the 1999 Australian Early Intervention Network for Mental Health in Young People newsletters for health professionals. The newsletters disseminate information about the national and local initiatives for intervention and prevention of mental health problems in young children and youth. The issues…

  9. Associations of overall sitting time and TV viewing time with fibrinogen and C reactive protein: the AusDiab study.

    PubMed

    Howard, Bethany J; Balkau, Beverley; Thorp, Alicia A; Magliano, Dianna J; Shaw, Jonathan E; Owen, Neville; Dunstan, David W

    2015-02-01

    Sedentary behaviour is associated with increased risk for all-cause and cardiovascular mortality. Plasma fibrinogen and C reactive protein (CRP)-key inflammatory and/or haemostatic markers-may contribute to this association; however, few studies have examined their relationships with sedentary behaviours. We examined associations of overall sitting and TV viewing time with fibrinogen and high-sensitivity CRP (hsCRP). Plasma fibrinogen and hsCRP were measured in 3086 Australian adults (mean age: 55±12 years) who participated in the 2004-2005 AusDiab (Australian Diabetes, Obesity and Lifestyle) study. Multiple linear regression analyses examined cross-sectional associations of self-reported overall sitting and TV viewing time (h/day) with plasma fibrinogen and hsCRP, adjusting for sociodemographic, behavioural and medical treatments and conditions as potential covariates. Overall sitting time and TV viewing time were positively associated with plasma fibrinogen (sitting: β: 0.02 g/L, 95% CI (0.01 to 0.02); TV time: 0.03 g/L (0.02 to 0.05)) and hsCRP (sitting: 2.4% (1.2% to 3.6%); TV time: 4.5% (1.7% to 7.4%)). Associations were independent of leisure-time physical activity, but after adjusting for waist circumference, they remained for fibrinogen, but for hsCRP were attenuated to the null. Interactions were observed for gender×TV (p=0.011) with fibrinogen (associations in women only) and for waist circumference×TV (p=0.084) with hsCRP (associations in low-risk only). Overall sitting time was positively associated with plasma fibrinogen and hsCRP in men and women; associations of TV viewing time with fibrinogen were observed in women only. Abdominal adiposity-mediated associations for hsCRP but not for fibrinogen. Prospective and intervention studies are needed to establish likely causality and elucidate potential mechanisms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  10. Performance Results for Massachusetts and Rhode Island Deep Energy Retrofit Pilot Community

    SciTech Connect

    Gates, C.; Neuhauser, K.

    2014-03-01

    Between December, 2009 and December, 2012, 42 deep energy retrofit (DER) projects were completed through a pilot program sponsored by National Grid and conducted in Massachusetts and Rhode Island. Thirty-seven of these projects were comprehensive retrofits while five were partial DERs, meaning that high performance retrofit was implemented for a single major enclosure component or a limited number of major enclosure components. Building Science Corporation developed a consistent "package" of measures in terms of the performance targeted for major building components. Based on the community experience, this DER package is expected to result in yearly source energy use near 110 MMBtu/year or approximately 40% below the Northeast regional average.

  11. Virtual-system-coupled adaptive umbrella sampling to compute free-energy landscape for flexible molecular docking.

    PubMed

    Higo, Junichi; Dasgupta, Bhaskar; Mashimo, Tadaaki; Kasahara, Kota; Fukunishi, Yoshifumi; Nakamura, Haruki

    2015-07-30

    A novel enhanced conformational sampling method, virtual-system-coupled adaptive umbrella sampling (V-AUS), was proposed to compute 300-K free-energy landscape for flexible molecular docking, where a virtual degrees of freedom was introduced to control the sampling. This degree of freedom interacts with the biomolecular system. V-AUS was applied to complex formation of two disordered amyloid-β (Aβ30-35 ) peptides in a periodic box filled by an explicit solvent. An interpeptide distance was defined as the reaction coordinate, along which sampling was enhanced. A uniform conformational distribution was obtained covering a wide interpeptide distance ranging from the bound to unbound states. The 300-K free-energy landscape was characterized by thermodynamically stable basins of antiparallel and parallel β-sheet complexes and some other complex forms. Helices were frequently observed, when the two peptides contacted loosely or fluctuated freely without interpeptide contacts. We observed that V-AUS converged to uniform distribution more effectively than conventional AUS sampling did.

  12. Statistical complexity, virial expansion, and van der Waals equation

    NASA Astrophysics Data System (ADS)

    Pennini, F.; Plastino, A.

    2016-09-01

    We investigate the notion of LMC statistical complexity with regards to a real gas and in terms of the second virial coefficient. The ensuing results are applied to the van der Waals equation. Interestingly enough, one finds a complexity-interpretation for the associated phase transition.

  13. Excited nucleon as a van der Waals system of partons

    SciTech Connect

    Jenkovszky, L. L.; Muskeyev, A. O. Yezhov, S. N.

    2012-06-15

    Saturation in deep inelastic scattering (DIS) and deeply virtual Compton scattering (DVCS) is associated with a phase transition between the partonic gas, typical of moderate x and Q{sup 2}, and partonic fluid appearing at increasing Q{sup 2} and decreasing Bjorken x. We suggest the van der Waals equation of state to describe properly this phase transition.

  14. HbA1c, fasting plasma glucose and the prediction of diabetes: Inter99, AusDiab and D.E.S.I.R.

    PubMed

    Soulimane, Soraya; Simon, Dominique; Shaw, Jonathan; Witte, Daniel; Zimmet, Paul; Vol, Sylviane; Borch-Johnsen, Knut; Magliano, Dianna; Vistisen, Dorte; Balkau, Beverley

    2012-06-01

    With diabetes defined by HbA1c≥6.5% and/or FPG≥7.0mmol/l and/or diabetes treatment, we investigated HbA1c and fasting plasma glucose (FPG) thresholds/change-points above which the incidence of diabetes increases. Data are Danish (Inter99), Australian (AusDiab) and French (D.E.S.I.R.), with respectively 4930, 6012 and 3784 non-diabetic participants. Diabetes incidences at 5 years for Inter99 and AusDiab and at 6 years for D.E.S.I.R. were 2.3%, 3.1% and 2.4% respectively and incidences increased with baseline HbA1c and FPG. As HbA1c distributions differed between cohorts, HbA1c was standardized on D.E.S.I.R. data. Change-points where diabetes incidence increased were identified for HbA1c (%) after standardization: 5.1 (4.9-5.6) (Inter99), 5.4 (5.1-5.6) (AusDiab), 5.3 (5.1-5.7) (D.E.S.I.R.); for FPG change-points (mmol/l) were 5.1 (…-6.1) (Inter99), 5.5 (5.2-5.8) (AusDiab), no change-point for D.E.S.I.R. Using current diabetes risk criteria HbA1c≥5.7% and/or FPG≥5.6mmol/l to screen for diabetes provided high sensitivity (over 89%) and positive predictive values: 4.3%, 6.9%, and 5.9% respectively. HbA1c and FPG change-points predicting incident diabetes did not always exist, differed across studies, when available were generally lower than current criteria with wide confidence intervals. Using jointly HbA1c≥5.7% and/or FPG≥5.6mmol/l as a criterion for the risk of incident diabetes is appropriate. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  15. Distributed Coordination of Energy Storage with Distributed Generators

    SciTech Connect

    Yang, Tao; Wu, Di; Stoorvogel, Antonie A.; Stoustrup, Jakob

    2016-07-18

    With a growing emphasis on energy efficiency and system flexibility, a great effort has been made recently in developing distributed energy resources (DER), including distributed generators and energy storage systems. This paper first formulates an optimal coordination problem considering constraints at both system and device levels, including power balance constraint, generator output limits, storage energy and power capacity and charging/discharging efficiencies. An algorithm is then proposed to dynamically and automatically coordinate DERs in a distributed manner. With the proposed algorithm, the agent at each DER only maintains a local incremental cost and updates it through information exchange with a few neighbors, without relying on any central decision maker. Simulation results are used to illustrate and validate the proposed algorithm.

  16. The potential for fast van der Waals computations for layered materials using a Lifshitz model

    NASA Astrophysics Data System (ADS)

    Zhou, Yao; Pellouchoud, Lenson A.; Reed, Evan J.

    2017-06-01

    Computation of the van der Waals (vdW) interactions plays a crucial role in the study of layered materials. The adiabatic-connection fluctuation-dissipation theorem within random phase approximation (ACFDT-RPA) has been empirically reported to be the most accurate of commonly used methods, but it is limited to small systems due to its computational complexity. Without a computationally tractable vdW correction, fictitious strains are often introduced in the study of multilayer heterostructures, which, we find, can change the vdW binding energy by as much as 15%. In this work, we employed for the first time a defined Lifshitz model to provide the vdW potentials for a spectrum of layered materials orders of magnitude faster than the ACFDT-RPA for representative layered material structures. We find that a suitably defined Lifshitz model gives the correlation component of the binding energy to within 8-20% of the ACFDT-RPA calculations for a variety of layered heterostructures. Using this fast Lifshitz model, we studied the vdW binding properties of 210 three-layered heterostructures. Our results demonstrate that the three-body vdW effects are generally small (10% of the binding energy) in layered materials for most cases, and that non-negligible second-nearest neighbor layer interaction and three-body effects are observed for only those cases in which the middle layer is atomically thin (e.g. BN or graphene). We find that there is potential for particular combinations of stacked layers to exhibit repulsive three-body van der Waals effects, although these effects are likely to be much smaller than two-body effects.

  17. Resonant two-photon ionization of fluorene rare-gas van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Leutwyler, Samuel; Even, Uzi; Jortner, Joshua

    1983-12-01

    Resonant two-photon ionization combined with time-of-flight mass spectrometry was applied for the interrogation of the S0 → S1 electronic-vibrational excitations of van der Waals complexes of fluorene (FL) with rare-gas atoms and N2 in supersonic jets. Energy-resolved and mass-resolved spectra of FL ṡ Ne, FL ṡ Arn (n=1-3), FL ṡ Kr, FL ṡ Xe, and FL ṡ N2 were recorded over the energy range 0-800 cm-1 above the electronic origin of S1. The red microscopic spectral shifts of the electronic origins of FL ṡ R (R=Ar, Kr, and Xe) complexes are dominated by dispersive interactions, being proportional to the polarizability of R. The vibrational level structure of FL ṡ Rn (R=Ar, Kr, and Xe) complexes exhibits intramolecular vibrational excitations of FL, as well as intermolecular vibrations, which involve the relative motion of FL and R in the complex. The spectra of FL ṡ Ne and FL ṡ N2 reveal a rich vibrational structure in the vicinity of the electronic origin, indicating a substantial change of the nuclear configuration upon electronic excitation. Upper and lower bounds on the dissociation energies of FL ṡ R (R=Ne, Kr, and Xe) and FL ṡ Ar2 were inferred from the vibrational level structure in the mass-resolved spectra, where the disappearance of the signal of the parent van der Waals ion and the appearance of the ion signal of the fragments mark the onset of the vibrational predissociation process.

  18. Demonstration of the Energy Component of the Installation Master Plan Using the Net Zero Energy Planner Tool: Cost and Performance Report

    DTIC Science & Technology

    2015-12-11

    SUBJECT TERMS Central Energy Plant, Deep Energy Retrofit, Energy Policy Act, Energy and Water, Energy Use Intensity, Greenhouse Gas, Geographic Information...3 Figure 2-2. NZP is a Web -based System. This Screen Shows a List of Studies to which the User has Access...DD Dry Dock DER Deep Energy Retrofit DHW Domestic Hot Water DoD U.S. Department of Defense DPW Directorate of Public Works ECBCS Energy

  19. Self-Consistent Density Functional Including Long-Range van der Waals Interactions

    NASA Astrophysics Data System (ADS)

    Ferri, Nicola; Distasio, Robert A., Jr.; Car, Roberto; Scheffler, Matthias; Tkatchenko, Alexandre

    2013-03-01

    Van der Waals (vdW) interactions are significant for a wide variety of systems, from noble-gas dimers to organic/inorganic interfaces. The long-range vdW energy is a tiny fraction (0.001%) of the total energy, hence it is typically assumed not to change electronic properties. Although the vdW-DF functional includes the effect of vdW energy on electronic structure, the influence of ``true'' long-range vdW interactions is difficult to assess since a significant part of vdW-DF energy arises from short distances. Here, we present a self-consistent (SC) implementation of the long-range Tkatchenko-Scheffler (TS) functional, including its extension to surfaces. The analysis of self-consistency for rare-gas dimers allows us to reconcile two different views on vdW interactions: (i) Feynman's view that claims changes in the electron density and (ii) atoms separated by infinite barrier. In agreement with previous work, we find negligible contribution from self-consistency in the structure and stability of vdW-bound complexes. However, a closer look at organic/inorganic interfaces reveals notable modification of energy levels when using the SC-TS vdW density functional.

  20. Evaluating dispersion forces for optimization of van der Waals complexes using a non-empirical functional

    NASA Astrophysics Data System (ADS)

    Arabi, Alya A.

    2016-11-01

    Modelling dispersion interactions with traditional density functional theory (DFT) is a challenge that has been extensively addressed in the past decade. The exchange-dipole moment (XDM), among others, is a non-empirical add-on dispersion correction model in DFT. The functional PW86+PBE+XDM for exchange, correlation and dispersion, respectively, compromises an accurate functional for thermochemistry and for van der Waals (vdW) complexes at equilibrium and non-equilibrium geometries. To use this functional in optimizing vdW complexes, rather than computing single point energies, it is necessary to evaluate accurate forces. The purpose of this paper is to validate that, along the potential energy surface, the distance at which the energy is minimum is commensurate with the distance at which the forces vanish to zero. This test was validated for 10 rare gas diatomic molecules using various integration grids and different convergence criteria. It was found that the use of either convergence criterion, 10-6 or 10-8, in Gaussian09, does not affect the accuracy of computed optimal distances and binding energies. An ultra-fine grid needs to be used when computing accurate energies using generalized gradient approximation functionals. This article is part of the themed issue 'Multiscale modelling at the physics-chemistry-biology interface'.

  1. Evaluating dispersion forces for optimization of van der Waals complexes using a non-empirical functional.

    PubMed

    Arabi, Alya A

    2016-11-13

    Modelling dispersion interactions with traditional density functional theory (DFT) is a challenge that has been extensively addressed in the past decade. The exchange-dipole moment (XDM), among others, is a non-empirical add-on dispersion correction model in DFT. The functional PW86+PBE+XDM for exchange, correlation and dispersion, respectively, compromises an accurate functional for thermochemistry and for van der Waals (vdW) complexes at equilibrium and non-equilibrium geometries. To use this functional in optimizing vdW complexes, rather than computing single point energies, it is necessary to evaluate accurate forces. The purpose of this paper is to validate that, along the potential energy surface, the distance at which the energy is minimum is commensurate with the distance at which the forces vanish to zero. This test was validated for 10 rare gas diatomic molecules using various integration grids and different convergence criteria. It was found that the use of either convergence criterion, 10(-6) or 10(-8), in Gaussian09, does not affect the accuracy of computed optimal distances and binding energies. An ultra-fine grid needs to be used when computing accurate energies using generalized gradient approximation functionals.This article is part of the themed issue 'Multiscale modelling at the physics-chemistry-biology interface'. © 2016 The Author(s).

  2. Van der Waals forces and electron-electron interactions in two strained graphene layers

    NASA Astrophysics Data System (ADS)

    Sharma, Anand; Harnish, Peter; Sylvester, Alexander; Kotov, Valeri N.

    2014-03-01

    We evaluate the van der Waals (vdW) interaction energy at T=0 between two undoped graphene layers which are separated by a finite distance. Our study is carried out within the Random Phase Approximation and the interaction energy is obtained for variation in the strength of effective Coulomb interaction and anisotropy due to applied uniaxial strain. We consider the following three models for the anisotropic case: a) where one of the two layers is uniaxially strained, b) the two layers are strained in the same direction, and c) one of the layers is strained in the perpendicular direction. We find that for all the three models and any given value of the coupling, the vdW interaction energy increases with increasing anisotropy. The effect is most striking for the case when both the layers are strained in the parallel direction where we observe up to an order of magnitude increase in the strained graphene relative to the unstrained case. We also investigate the effect of intra-layer electron-electron interactions in the region of large separation between the strained graphene layers. We conclude that the many-body contributions to the correlation energy are non-negligible and the vdW interaction energy decreases as a function of increasing distance between the layers. Alexander Sylvester acknowledges financial assistance from the Research Experiences for Undergraduates (REU) Program of the National Science Foundation (NSF) focussing on complex materials.

  3. The role of van der Waals interactions in the adsorption of noble gases on metal surfaces.

    PubMed

    Chen, De-Li; Al-Saidi, W A; Johnson, J Karl

    2012-10-24

    Adsorption of noble gases on metal surfaces is determined by weak interactions. We applied two versions of the nonlocal van der Waals density functional (vdW-DF) to compute adsorption energies of Ar, Kr, and Xe on Pt(111), Pd(111), Cu(111), and Cu(110) metal surfaces. We compared our results with data obtained using other density functional approaches, including the semiempirical vdW-corrected DFT-D2. The vdW-DF results show considerable improvements in the description of adsorption energies and equilibrium distances over other DFT based methods, giving good agreement with experiments. We also calculated perpendicular vibrational energies for noble gases on the metal surfaces using vdW-DF data and found excellent agreement with available experimental results. Our vdW-DF calculations show that adsorption of noble gases on low-coordination sites is energetically favored over high-coordination sites, but only by a few meV. Analysis of the two-dimensional potential energy surface shows that the high-coordination sites are local maxima on the two-dimensional potential energy surface and therefore unlikely to be observed in experiments; this provides an explanation of the experimental observations. The DFT-D2 approach with the standard parameterization was found to overestimate the dispersion interactions, and to give the wrong adsorption site preference for four of the nine systems we studied.

  4. The role of van der Waals interactions in the adsorption of noble gases on metal surfaces

    SciTech Connect

    Chen, De-Li; Al-Saidi, W A; Johnson, J Karl

    2012-10-03

    Adsorption of noble gases on metal surfaces is determined by weak interactions. We applied two versions of the nonlocal van der Waals density functional (vdW-DF) to compute adsorption energies of Ar, Kr, and Xe on Pt(111), Pd(111), Cu(111), and Cu(110) metal surfaces. We have compared our results with data obtained using other density functional approaches, including the semiempirical vdW corrected DFT-D2. The vdW-DF results show considerable improvements in the description of adsorption energies and equilibrium distances over other DFTbased methods, giving good agreement with experiments. We have also calculated perpendicular vibrational energies for noble gases on the metal surfaces using vdWDF data and found excellent agreement with available experimental results. Our vdW-DF calculations show that adsorption of noble gases on low-coordination sites is energetically favored over high-coordination sites, but only by a few meV. Analysis of the 2-dimensional potential energy surface shows that the high-coordination sites are local maxima on the 2-dimensional potential energy surface and therefore unlikely to be observed in experiments, which provides an explanation of the experimental observations. The DFT-D2 approach with the standard parameterization was found to overestimate the dispersion interactions, and to give the wrong adsorption site preference for four of the nine systems we studied.

  5. Electron acceleration at localized wave structures in the solar corona (German Title: Elektronenbeschleunigung an lokalen Wellenstrukturen in der Sonnenkorona)

    NASA Astrophysics Data System (ADS)

    Miteva, Rositsa Stoycheva

    2007-07-01

    in the electric and magnetic wave field within just several whistler periods. While gaining energy from the whistler wave field, the electrons reach the shock front and, subsequently, a major part of them are reflected back into the upstream region, since the shock accompanied with a jump of the magnetic field acts as a magnetic mirror. Co-moving with the whistlers now, the reflected electrons are out of resonance and hence can propagate undisturbed into the far upstream region, where they are detected in terms of type II metric radio bursts. In summary, the kinetic energy of protons is transfered into electrons by the action of localized wave structures in both cases, i.e., at jets outflowing from the magnetic reconnection site and at shock waves in the corona. Die Sonne ist ein aktiver Stern, was sich nicht nur in den allseits bekannten Sonnenflecken, sondern auch in Flares manifestiert. Während Flares wird eine große Menge gespeicherter, magnetischer Energie in einer kurzen Zeit von einigen Sekunden bis zu wenigen Stunden in der Sonnenkorona freigesetzt. Dabei werden u.a. energiereiche Elektronen erzeugt, die ihrerseits nichtthermische Radio- und Röntgenstrahlung, wie sie z.B. am Observatorium für solare Radioastronomie des Astrophysikalischen Instituts Potsdam (AIP) in Tremsdorf und durch den NASA-Satelliten RHESSI beobachtet werden, erzeugen. Da diese Elektronen einen beträchtlichen Anteil der beim Flare freigesetzten Energie tragen, ist die Frage, wie Elektronen in kurzer Zeit auf hohe Energien in der Sonnenkorona beschleunigt werden, von generellem astrophysikalischen Interesse, da solche Prozesse auch in anderen Sternatmosphären und kosmischen Objekten, wie z.B. Supernova-Überresten, stattfinden. In der vorliegenden Dissertation wird die Elektronenbeschleunigung an lokalen Wellenstrukturen im Plasma der Sonnenkorona untersucht. Solche Wellen treten in der Umgebung der magnetischen Rekonnektion, die als ein wichtiger Auslöser von Flares angesehen wird

  6. Effect of van der Waals interactions on the chemisorption and physisorption of phenol and phenoxy on metal surfaces

    NASA Astrophysics Data System (ADS)

    Peköz, Rengin; Donadio, Davide

    2016-09-01

    The adsorption of phenol and phenoxy on the (111) surface of Au and Pt has been investigated by density functional theory calculations with the conventional PBE functional and three different non-local van der Waals (vdW) exchange and correlation functionals. It is found that both phenol and phenoxy on Au(111) are physisorbed. In contrast, phenol on Pt(111) presents an adsorption energy profile with a stable chemisorption state and a weakly metastable physisorbed precursor. While the use of vdW functionals is essential to determine the correct binding energy of both chemisorption and physisorption states, the relative stability and existence of an energy barrier between them depend on the semi-local approximations in the functionals. The first dissociation mechanism of phenol, yielding phenoxy and atomic hydrogen, has been also investigated, and the reaction and activation energies of the resulting phenoxy on the flat surfaces of Au and Pt were discussed.

  7. Plug-in Electric Vehicle Interactions with a Small Office Building: An Economic Analysis using DER-CAM

    SciTech Connect

    Momber, Ilan; Gomez, Tomás; Venkataramanan, Giri; Stadler, Michael; Beer, Sebastian; Lai, Judy; Marnay, Chris; Battaglia, Vincent

    2010-06-01

    It is generally believed that plug-in electric vehicles (PEVs) offer environmental and energy security advantages compared to conventional vehicles. Policies are stimulating electric transportation deployment, and PEV adoption may grow significantly. New technology and business models are being developed to organize the PEV interface and their interaction with the wider grid. This paper analyzes the PEVs' integration into a building's Energy Management System (EMS), differentiating between vehicle to macrogrid (V2M) and vehicle to microgrid (V2m) applications. This relationship is modeled by the Distributed Energy Resources Customer Adoption Model (DER-CAM), which finds optimal equipment combinations to meet microgrid requirements at minimum cost, carbon footprint, or other criteria. Results derive battery value to the building and the possibility of a contractual affiliation sharing the benefit. Under simple annual fixed payments and energy exchange agreements, vehicles are primarily used to avoid peak demand charges supplying cheaper off-peak electricity to the building during workdays.

  8. Performance Results for Massachusetts and Rhode Island Deep Energy Retrofit Pilot Community

    SciTech Connect

    Gates, C.; Neuhauser, K.

    2014-03-01

    Between December, 2009 and December, 2012 42 deep energy retrofit (DER) projects were completed through a DER pilot program sponsored by National Grid and conducted in Massachusetts and Rhode Island. 37 of these projects were comprehensive retrofits while 5 were partial DERs, meaning that high performance retrofit was implemented for a single major enclosure component or a limited number of major enclosure components. The 42 DER projects represent 60 units of housing. The comprehensive projects all implemented a consistent 'package' of measures in terms of the performance targeted for major building components. Projects exhibited some variations in the approach to implementing the retrofit package. Pre- and post-retrofit air leakage measurements were performed for each of the projects. Each project also reported information about project costs including identification of energy-related costs. Post-retrofit energy-use data was obtained for 29 of the DER projects. Post-retrofit energy use was analyzed based on the net energy used by the DER project regardless of whether the energy was generated on site or delivered to the site. Homeowner surveys were returned by 12 of the pilot participants. Based on the community experience, this DER package is expected to result in yearly source energy use near 110 MMBtu/year or approximately 40% below the Northeast regional average. Larger to medium sized homes that successful implement these retrofits can be expected to achieve source EUI that is comparable to Passive House targets for new construction. The community of DER projects show post-retrofit airtightness below 1.5 ACH50 to be eminently achievable.

  9. National Grid Deep Energy Retrofit Pilot, Massachusetts and Rhode Island (Fact Sheet)

    SciTech Connect

    Not Available

    2014-03-01

    Between December, 2009 and December, 2012 42 deep energy retrofit (DER) projects were completed through a DER pilot program sponsored by National Grid and conducted in Massachusetts and Rhode Island. 37 of these projects were comprehensive retrofits while 5 were partial DERs, meaning that high performance retrofit was implemented for a single major enclosure component or a limited number of major enclosure components. The 42 DER projects represent 60 units of housing. The comprehensive projects all implemented a consistent "package" of measures in terms of the performance targeted for major building components. Projects exhibited some variations in the approach to implementing the retrofit package. Pre- and post-retrofit air leakage measurements were performed for each of the projects. Each project also reported information about project costs including identification of energy-related costs. Post-retrofit energy-use data was obtained for 29 of the DER projects. Post-retrofit energy use was analyzed based on the net energy used by the DER project regardless of whether the energy was generated on site or delivered to the site. Homeowner surveys were returned by 12 of the pilot participants. Based on the community experience, this DER package is expected to result in yearly source energy use near 110 MMBtu/year or approximately 40% below the Northeast regional average. Larger to medium sized homes that successful implement these retrofits can be expected to achieve source EUI that is comparable to Passive House targets for new construction. The community of DER projects show post-retrofit airtightness below 1.5 ACH50 to be eminently achievable.

  10. Adsorption of polyiodobenzene molecules on the Pt(111) surface using van der Waals density functional theory

    NASA Astrophysics Data System (ADS)

    Johnston, Karen; Pekoz, Rengin; Donadio, Davide

    2016-02-01

    Adsorption of aromatic molecules on surfaces is widely studied due to applications in molecular electronics. In this work, the adsorption of iodobenzene molecules on the Pt(111) surface has been studied using density functional theory. Iodobenzene molecules, with various numbers of iodine atoms, have two non-dissociative adsorption minima. One structure exhibits chemisorption between the ring and the surface (short-range) and the other structure exhibits chemisorption between the iodine ions and the surface (long-range). Both structures have a strong van der Waals interaction with the surface. In general, the adsorption energy increases as the number of iodine atoms increases. The dissociated structure of monoiodobenzene was investigated, and the dissociation barrier and the barrier between the short- and long-range states were compared.

  11. Microwave Observation of the Van Der Waals Complex O_2-CO

    NASA Astrophysics Data System (ADS)

    Marshall, Frank E.; Persinger, Thomas D.; Gillcrist, David Joseph; Moon, Nicole; Ndengue, Steve Alexandre; Dawes, Richard; Grubbs, G. S., II

    2016-06-01

    FTMW spectroscopy has long been known to be a powerful tool in characterizing van der Waals complexes. Along with this, advances in microwave technology and computing have made complicated spin-interaction systems much easier to observe and characterize. One such system, O_2-CO has been observed for the first time on a CP-FTMW spectrometer operational in the 6-18 GHz region. Preliminary observations and calculations indicate a slipped-parallel structure. High level calculations are ongoing, including the construction of a 4D potential energy surface. Rotational assignments, along with any observed fine structure due to the ^3Σ ground state of O_2 will be discussed. Stewart Novick, Bibliography of Rotational Spectra of Weakly Bound Complexes

  12. Van der Waals-like behaviour of charged black holes and hysteresis in the dual QFTs

    NASA Astrophysics Data System (ADS)

    Cadoni, Mariano; Franzin, Edgardo; Tuveri, Matteo

    2017-05-01

    Using the rules of the AdS/CFT correspondence, we compute the spherical analogue of the shear viscosity, defined in terms of the retarded Green function for the stress-energy tensor for QFTs dual to five-dimensional charged black holes of general relativity with a negative cosmological constant. We show that the ratio between this quantity and the entropy density, η ˜ / s, exhibits a temperature-dependent hysteresis. We argue that this hysteretic behaviour can be explained by the Van der Waals-like character of charged black holes, considered as thermodynamical systems. Under the critical charge, hysteresis emerges owing to the presence of two stable states (small and large black holes) connected by a meta-stable region (intermediate black holes). A potential barrier prevents the equilibrium path between the two stable states; the system evolution must occur through the meta-stable region, and a path-dependence of η ˜ / s is generated.

  13. Communication: Multiple-property-based diabatization for open-shell van der Waals molecules

    NASA Astrophysics Data System (ADS)

    Karman, Tijs; van der Avoird, Ad; Groenenboom, Gerrit C.

    2016-03-01

    We derive a new multiple-property-based diabatization algorithm. The transformation between adiabatic and diabatic representations is determined by requiring a set of properties in both representations to be related by a similarity transformation. This set of properties is determined in the adiabatic representation by rigorous electronic structure calculations. In the diabatic representation, the same properties are determined using model diabatic states defined as products of undistorted monomer wave functions. This diabatic model is generally applicable to van der Waals molecules in arbitrary electronic states. Application to locating seams of conical intersections and collisional transfer of electronic excitation energy is demonstrated for O2 - O2 in low-lying excited states. Property-based diabatization for this test system included all components of the electric quadrupole tensor, orbital angular momentum, and spin-orbit coupling.

  14. Epitaxial 2D SnSe2/ 2D WSe2 van der Waals Heterostructures.

    PubMed

    Aretouli, Kleopatra Emmanouil; Tsoutsou, Dimitra; Tsipas, Polychronis; Marquez-Velasco, Jose; Aminalragia Giamini, Sigiava; Kelaidis, Nicolaos; Psycharis, Vassilis; Dimoulas, Athanasios

    2016-09-07

    van der Waals heterostructures of 2D semiconductor materials can be used to realize a number of (opto)electronic devices including tunneling field effect devices (TFETs). It is shown in this work that high quality SnSe2/WSe2 vdW heterostructure can be grown by molecular beam epitaxy on AlN(0001)/Si(111) substrates using a Bi2Se3 buffer layer. A valence band offset of 0.8 eV matches the energy gap of SnSe2 in such a way that the VB edge of WSe2 and the CB edge of SnSe2 are lined up, making this materials combination suitable for (nearly) broken gap TFETs.

  15. Excitons in van der Waals materials: From monolayer to bulk hexagonal boron nitride

    NASA Astrophysics Data System (ADS)

    Koskelo, Jaakko; Fugallo, Giorgia; Hakala, Mikko; Gatti, Matteo; Sottile, Francesco; Cudazzo, Pierluigi

    2017-01-01

    We present a general picture of the exciton properties of layered materials in terms of the excitations of their single-layer building blocks. To this end, we derive a model excitonic Hamiltonian by drawing an analogy with molecular crystals, which are other prototypical van der Waals materials. We employ this simplified model to analyze in detail the excitation spectrum of hexagonal boron nitride (hBN) that we have obtained from the ab initio solution of the many-body Bethe-Salpeter equation as a function of momentum. In this way, we identify the character of the lowest-energy excitons in hBN, discuss the effects of the interlayer hopping and the electron-hole exchange interaction on the exciton dispersion, and illustrate the relation between exciton and plasmon excitations in layered materials.

  16. The T-shaped KrI2(ion-pair states) van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Baturo, V. V.; Kevorkyants, R.; Lukashov, S. S.; Poretsky, S. A.; Pravilov, A. M.; Zhironkin, A. I.

    2017-09-01

    The T-shaped KrI2(E0g+) van der Waals complexes have been observed and studied for the first time. Analysis of the luminescence excitation spectra as well as luminescence spectra themselves in the spectral ranges, where the I2(E0g+ → B0u+, D0u+ → X0g+, β1g → A1u and D‧2g → A‧2u) transitions can occur, has been carried out. Branching ratios of the iodine molecule state formation and vibronic level population, as well as the potential parameters of the KrI2(E,vE = 0-8, nE) complexes have been determined. Binding energies of the KrI2(X0g+ ,vX = 0, nX = 0 and B0u+,vB = 19, nB = 0) complexes have been also estimated.

  17. Scanning tunneling spectroscopy of van der Waals graphene/semiconductor interfaces: absence of Fermi level pinning

    NASA Astrophysics Data System (ADS)

    Le Quang, T.; Cherkez, V.; Nogajewski, K.; Potemski, M.; Dau, M. T.; Jamet, M.; Mallet, P.; Veuillen, J.-Y.

    2017-09-01

    We have investigated the electronic properties of two-dimensional (2D) transition metal dichalcogenides (TMDs), namely trilayer WSe2 and monolayer MoSe2, deposited on epitaxial graphene on silicon carbide, by using scanning tunneling microscopy and spectroscopy (STM/STS) in ultra-high vacuum. Depending on the number of graphene layers below the TMD flakes, we identified variations in the electronic dI/dV(V) spectra measured by the STM tip: the most salient feature is a rigid shift of the TMD spectra (i.e. of the different band onset positions) towards occupied states by about 120 mV when passing from bilayer to monolayer underlying graphene. Since both graphene phases are metallic and present a work function difference in the same energy range, our measurements point towards the absence of Fermi-level pinning for such van der Waals 2D TMD/Metal heterojunctions, following the prediction of the Schottky-Mott model.

  18. Repulsive van der waals forces self-limit native oxide growth.

    PubMed

    Bohling, Christian; Sigmund, Wolfgang

    2015-05-05

    Silicon is one of the most studied materials, yet questions remain unanswered about its unusual property of growing a self-limiting native oxide that attains its final thickness in a matter of hours yet months later has not grown further. For the first time, we have explored this self-limiting growth in terms of repulsive van der Waals (vdW) forces generated by the combination of material properties inherent to the system. These repulsive forces represent an energy barrier preventing additional oxidizing chemicals, mainly oxygen and water, from adsorbing on the surface as well as hindering diffusion of those that do adsorb toward the interface. We have also proven that this native oxide can be increased in thickness at room temperature and without reactive species by changing the oxidation environment to one predicted by theory to result in attractive vdW forces, thus allowing oxygen/water to interact with the surface more freely.

  19. Classical van der Waals interactions between spherical bodies of dipolar fluid.

    PubMed

    Stenhammar, Joakim; Trulsson, Martin

    2011-07-01

    The van der Waals interaction free energy A(int) between two spherical bodies of Stockmayer fluid across a vacuum is calculated using molecular simulations and classical perturbation theory. The results are decomposed into their electrostatic and Lennard-Jones parts, and the former is shown to agree excellently with predictions from dielectric continuum theory. A(int) is decomposed into its energetic and entropic contributions and the results are compared with analytical predictions. Finally, we expand the electrostatic part of A(int) in a multipole expansion, and show that the surprisingly good agreement between the molecular and continuum descriptions is likely due to a cancellation of errors coming from the neglect of the discrete nature of the fluid within the dielectric description.

  20. The development of two dimensional group IV chalcogenides, blocks for van der Waals heterostructures

    NASA Astrophysics Data System (ADS)

    Sa, Baisheng; Sun, Zhimei; Wu, Bo

    2015-12-01

    In this work, we introduce a series of two dimensional (2D) group IV chalcogenides (AX)2 with the building block X-A-A-X (A = Si, Ge, Sn, and Pb, and X = Se and Te) on the basis of ab initio calculations. The analysis of energy evaluation, lattice vibration as well as the chemical bonding demonstrate the good stability of these 2D materials. Furthermore, the pictures for the chemical bonding and electronic features of the 2D (AX)2 are drawn. Their narrow gapped semiconducting nature is unraveled. Especially, strong interactions between the electrons and phonons as well as the topological insulating nature in (SiTe)2 are observed. The present results indicate that such remarkable artificial 2D (AX)2 are building blocks for van der Waals heterostructure engineering, which shows potential applications in nanoscaled electronics and optoelectronics.

  1. Experiment and computation: a combined approach to study the van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Surin, L. A.

    2016-12-01

    A review of recent results on the millimetre-wave spectroscopy of weakly bound van der Waals complexes, mostly those which contain H2 and He, is presented. In our work, we compared the experimental spectra to the theoretical bound state results, thus providing a critical test of the quality of the M-H2 and M-He potential energy surfaces (PESs) which are a key issue for reliable computations of the collisional excitation and de-excitation of molecules (M = CO, NH3, H2O) in the dense interstellar medium. The intermolecular interactions with He and H2 play also an important role for high resolution spectroscopy of helium or para-hydrogen clusters doped by a probe molecule (CO, HCN). Such experiments are directed on the detection of superfluid response of molecular rotation in the He and p-H2 clusters.

  2. Self-consistent van der Waals density functional study of benzene adsorption on Si(100)

    NASA Astrophysics Data System (ADS)

    Hamamoto, Yuji; Hamada, Ikutaro; Inagaki, Kouji; Morikawa, Yoshitada

    2016-06-01

    The adsorption of benzene on the Si(100) surface is studied theoretically using the self-consistent van der Waals density functional (vdW-DF) method. The adsorption energies of two competing adsorption structures, butterfly (BF) and tight-bridge (TB) structures, are calculated with several vdW-DFs at saturation coverage. Our results show that recently proposed vdW-DFs with high accuracy all prefer TB to BF, in accord with more accurate calculations based on exact exchange and correlation within the random-phase approximation. Detailed analyses reveal the important roles played by the molecule-surface interaction and molecular deformation upon adsorption, and we suggest that their precise description is a prerequisite for accurate prediction of the most stable adsorption structure of organic molecules on semiconductor surfaces.

  3. Dietary energy requirements in relatively healthy maintenance hemodialysis patients estimated from long-term metabolic studies1

    PubMed Central

    Shah, Anuja; Bross, Rachelle; Shapiro, Bryan B; Morrison, Gillian; Kopple, Joel D

    2016-01-01

    Background: Studies that examined dietary energy requirements (DERs) of patients undergoing maintenance hemodialysis (MHD) have shown mixed results. Many studies reported normal DERs, but some described increased energy needs. DERs in MHD patients have been estimated primarily from indirect calorimetry and from nitrogen balance studies. The present study measured DERs in MHD patients on the basis of their dietary energy intake and changes in body composition. Objective: This study assessed DERs in MHD patients who received a constant energy intake while changes in their body composition were measured. Design: Seven male and 6 female sedentary, clinically stable MHD patients received a constant mean (±SD) energy intake for 92.2 ± 7.9 d while residing in a metabolic research ward. Changes in fat and fat-free mass, measured by dual-energy X-ray absorptiometry, were converted to calorie equivalents and added to energy intake to calculate energy requirements. Results: The average DER was 31 ± 3 kcal · kg−1 · d−1 calculated from energy intake and change in fat and fat-free calories, which was 28 ± 197 kcal/d over the 92 d of the study. DERs of MHD patients correlated strongly with their body weight (r = 0.81, P = 0.002) and less closely with their measured resting energy expenditure expressed as kcal/d (r = 0.69, P = 0.01). Although the average observed DER in MHD patients was similar to published estimated values for normal sedentary individuals of similar age and sex, there was wide variability in DER among individual patients (range: 26–36 kcal · kg−1 · d−1). Conclusions: Average DERs of sedentary, clinically stable patients receiving MHD are similar to those of sedentary normal individuals. Our data do not support the theory that MHD patients have increased DERs. Due to the high variability in DERs, careful monitoring of the nutritional status of individual MHD patients is essential. This trial was registered at clinicaltrials.gov as NCT02194114

  4. EDITORIAL: Van der Waals interactions in advanced materials, in memory of David C Langreth Van der Waals interactions in advanced materials, in memory of David C Langreth

    NASA Astrophysics Data System (ADS)

    Hyldgaard, Per; Rahman, Talat S.

    2012-10-01

    rationale for considering a more general switch to nonlocal functionals. Graziano et al note that the accuracy in the description of some soft layered systems like graphene and boron-nitride can be increased by changing the exchange description away from what was suggested in the original vdW-DF method. Hanke et al focused on the weak chemisorption of ethene on the various Cu facets that have an increasing degree of openness and provide a method for benchmarking through comparison with experimental observations. Finally, Björkman et al raise the question 'Are we van der Waals ready?' and proceed to test our readiness by benchmarking the performance of a range of vdW-aware methods for the group of 96 known layered structures. We have also included in this special issue one study of nonequilibrium transport which is linked to David's work in formal scattering theory [1, 2] and which observes that vdW forces (and possible generalizations to nonequilibrium transport conditions) will be of central importance in a richer computational characterization of molecular electronics under operational conditions. David was always keen to spearhead the development of tools that improved descriptions of nature and addressed actual experiments. We know that he was happy that DMP started the focused session on vdW and materials in 2011. We know that he would have thoroughly appreciated the articles in this special issue. He would have hoped, as we do, that materials theory may continue to learn how to tackle even more exciting experimental problems and that we may continue to deepen our understanding of materials and their functionality. Bibliography [1]Langreth D C 1976 1975 Nato Advanced Study Institute on Linear and Nonlinear Transport in Solids, Antwerben vol B17 (New York: Plenum) pp 3-32 [2]Langreth D C 1966 Friedel sum rule for Anderson's model of localized impurity states Phys. Rev. 150 516 [3]Langreth D C and Perdew J P 1975 The exchange-correlation energy of a metallic surface

  5. Short-Term Test Results: Multifamily Home Energy Efficiency Retrofit

    SciTech Connect

    Lyons, J.

    2013-01-01

    Multifamily deep energy retrofits (DERs) represent great potential for energy savings, while also providing valuable insights on research-generated efficiency measures, cost-effectiveness metrics, and risk factor strategies for the multifamily housing industry. The Bay Ridge project is comprised of a base scope retrofit with a goal of achieving 30% savings (relative to pre-retrofit), and a DER scope with a goal of 50% savings (relative to pre-retrofit). The base scope has been applied to the entire complex, except for one 12-unit building which underwent the DER scope. Findings from the implementation, commissioning, and short-term testing at Bay Ridge include air infiltration reductions of greater than 60% in the DER building; a hybrid heat pump system with a Savings to Investment Ratio (SIR) > 1 (relative to a high efficiency furnace) which also provides the resident with added incentive for energy savings; and duct leakage reductions of > 60% using an aerosolized duct sealing approach. Despite being a moderate rehab instead of a gut rehab, the Bay Ridge DER is currently projected to achieve energy savings ≥ 50% compared to pre-retrofit, and the short-term testing supports this estimate.

  6. Vibronic structure of the cyclopentadienyl radical and its nonrigid van der Waals cluster with nitrogen

    NASA Astrophysics Data System (ADS)

    Sun, S.; Bernstein, E. R.

    1995-09-01

    Fluorescence excitation and two color mass resolved excitation spectroscopy are employed to study the D1(2A2″)←D0(2E1″) vibronic transitions of the cyclopentadienyl radical (cpd) and its van der Waals cluster with nitrogen. The radical is created by photolysis of the cyclopentadiene dimer and cooled by expansion from a supersonic nozzle. The cpd(N2)1 cluster is generated in this cooling process. Mass resolved excitation spectra of cpd are obtained for the first 1200 cm-1 of the D1←D0 transition. The excitation spectrum of cpd(N2)1 shows a complicated structure for the origin transition. With the application of hole burning spectroscopy, we are able to assign all the cluster transitions to a single isomer. The features are assigned to a 55 cm-1 out-of-plane van der Waals mode stretch and contortional (rotational) motions of the N2 molecule with respect to the cpd radical. Empirical potential energy calculations are used to predict the properties of this cluster and yield the following results: (1) the N2 molecular axis is perpendicular to the cpd fivefold axis and parallel to the plane of the cpd ring with the two molecular centers of mass lying on the fivefold ring axis; (2) the binding energy of cpd(N2)1 is 434 cm-1; and (3) the rotational motion of the N2 molecule is essentially unhindered about the cpd fivefold axis. The molecular symmetry group D5h(MS) is applied to the nonrigid cluster, and optical selection rules exclude even↔odd transitions (Δn=0, ±2, ±4,... allowed) between the different contortional levels. Tentative assignments are given to the observed contortional features based on these considerations. The barrier to internal rotation is also small in the excited state. The results for the cpd(N2)1 van der Waals cluster are compared to those for the benzene (N2)1 and benzyl radical (N2)1 clusters.

  7. Optimal Energy Management for Microgrids

    NASA Astrophysics Data System (ADS)

    Zhao, Zheng

    Microgrid is a recent novel concept in part of the development of smart grid. A microgrid is a low voltage and small scale network containing both distributed energy resources (DERs) and load demands. Clean energy is encouraged to be used in a microgrid for economic and sustainable reasons. A microgrid can have two operational modes, the stand-alone mode and grid-connected mode. In this research, a day-ahead optimal energy management for a microgrid under both operational modes is studied. The objective of the optimization model is to minimize fuel cost, improve energy utilization efficiency and reduce gas emissions by scheduling generations of DERs in each hour on the next day. Considering the dynamic performance of battery as Energy Storage System (ESS), the model is featured as a multi-objectives and multi-parametric programming constrained by dynamic programming, which is proposed to be solved by using the Advanced Dynamic Programming (ADP) method. Then, factors influencing the battery life are studied and included in the model in order to obtain an optimal usage pattern of battery and reduce the correlated cost. Moreover, since wind and solar generation is a stochastic process affected by weather changes, the proposed optimization model is performed hourly to track the weather changes. Simulation results are compared with the day-ahead energy management model. At last, conclusions are presented and future research in microgrid energy management is discussed.

  8. Smart Microgrid Energy Management Controls for Improved Energy Efficiency and Renewables Integration at DoD Installations

    DTIC Science & Technology

    2013-04-01

    Device JCI: Johnson Conrols, Inc. LAN : Local Area Network MCAGCC: Marine Corps Air Ground Combat Center MCS: Microgrid Control System Multilin...distribution losses. Microgrids are envisioned as local power networks that utilize distributed energy resources (DER) and manage the local energy...Platforms (supervisory controller, the HMI, the BEM, and certified network communications) hardware and software tailored for the Twentynine Palms

  9. van der Waals Contribution to the Relative Stability of Aqueous Zn(2+) Coordination States.

    PubMed

    Ducher, Manoj; Pietrucci, Fabio; Balan, Etienne; Ferlat, Guillaume; Paulatto, Lorenzo; Blanchard, Marc

    2017-07-11

    Many properties of aqueous cations depend on their coordination state. However, the lack of long-range order and the dynamic character of aqueous solutions make it difficult to obtain information beyond average coordination parameters. A thorough understanding of the molecular-scale environment of aqueous cations usually requires a combination of experimental and theoretical approaches. In the case of Zn(2+), significant discrepancies occur among theoretical investigations based on first-principles molecular dynamics (FPMD) or free-energy calculations, although experimental data consistently point to a dominant hexaaquo-zinc complex (Zn[H2O]6)(2+) in pure water. In the present study, the aqueous speciation of zinc is theoretically investigated by combining FPMD simulations and free-energy calculations based on metadynamics and umbrella-sampling strategies. The simulations are carried out within the density functional theory (DFT) framework using for the exchange-correlation functional either a standard generalized gradient approximation (GGA) or a nonlocal functional (vdw-DF2) which includes van der Waals interactions. The theoretical environment of Zn is confronted to experiment by comparing calculated and measured X-ray absorption spectra. It is shown that the inclusion of van der Waals interactions is crucial for the correct modeling of zinc aqueous speciation, whereas GGA incorrectly favors tetraaquo- (Zn[H2O]4)(2+) and pentaaquo-zinc (Zn[H2O]5)(2+) complexes, results obtained with the vdW-DF2 functional show that the hexaaquo-zinc complex is more stable than the tetraaquo and pentaaquo-zinc complexes by 13 and by 4 kJ mol(-1), respectively. These results highlight the critical importance of even subtle interactions for the correct balance of different coordination states in aqueous solutions. However, for a given coordination state, GGA leads to a reasonable description of the geometry of the aqueous complex.

  10. Excitons in van der Waals heterostructures: The important role of dielectric screening

    NASA Astrophysics Data System (ADS)

    Latini, S.; Olsen, T.; Thygesen, K. S.

    2015-12-01

    The existence of strongly bound excitons is one of the hallmarks of the newly discovered atomically thin semiconductors. While it is understood that the large binding energy is mainly due to the weak dielectric screening in two dimensions, a systematic investigation of the role of screening on two-dimensional (2D) excitons is still lacking. Here we provide a critical assessment of a widely used 2D hydrogenic exciton model, which assumes a dielectric function of the form ɛ (q )=1 +2 π α q , and we develop a quasi-2D model with a much broader applicability. Within the quasi-2D picture, electrons and holes are described as in-plane point charges with a finite extension in the perpendicular direction, and their interaction is screened by a dielectric function with a nonlinear q dependence which is computed ab initio. The screened interaction is used in a generalized Mott-Wannier model to calculate exciton binding energies in both isolated and supported 2D materials. For isolated 2D materials, the quasi-2D treatment yields results almost identical to those of the strict 2D model, and both are in good agreement with ab initio many-body calculations. On the other hand, for more complex structures such as supported layers or layers embedded in a van der Waals heterostructure, the size of the exciton in reciprocal space extends well beyond the linear regime of the dielectric function, and a quasi-2D description has to replace the 2D one. Our methodology has the merit of providing a seamless connection between the strict 2D limit of isolated monolayer materials and the more bulk-like screening characteristics of supported 2D materials or van der Waals heterostructures.

  11. Rovibronic spectroscopy of the van der Waals complex He-HCl+

    NASA Astrophysics Data System (ADS)

    Dhont, G.; Chambaud, G.; Groenenboom, G. C.; van der Avoird, A.

    2004-01-01

    The potential energy surfaces and the calculated rovibronic spectrum of the electronic ground state of the van der Waals He-HCl+ cation are presented. The system is in a X2Π electronic state at linearity, which splits into an A' and an A'' state upon bending, leading to a Renner-Teller effect. Three-dimensional potential energy surfaces have been determined using the partially spin-restricted open-shell single and double excitation coupled cluster method with perturbative triples [RCCSD(T)]. The absolute minimum of a two-dimensional surface with the diatom bond length r fixed at re = 2.489 a0 is located at the linear He-HCl+ geometry with a van der Waals bond length R of 5.98 a0 and De ≃ 300 cm-1. The minimum in the full three-dimensional potential occurs for a slightly larger value of r: 2.492 a0. The rovibronic levels of the He-HCl+ complex have been computed by a variational method for total angular momenta J =1/2, 3/2, 5/2, 7/2 and 9/2. The binding energy D0 is calculated as 161.5 cm-1 using the two-dimensional potential energy surfaces with r frozen at re and as 163.5 cm-1 in full three-dimensional calculations. Owing to the large and negative value of the spin-orbit parameter in HCl+ (ASO = -648.13 cm-1), all the considered rovibronic states correspond to the |Ω| = 3/2 spin-orbit component of HCl+. The nuclear wave functions of the complex could be interpreted using the model of a slightly hindered diatomic rotor. The energy level pattern and wave functions have been compared with the more floppy Ar-OH complex on the one hand and the more rigid He-HF+ system on the other. The anisotropy of the potential energy surface of the He-HCl+ complex is intermediate between these two cases and the rovibronic states reflect this property.

  12. Heterogeneous dielectric generalized Born model with a van der Waals term provides improved association energetics of membrane-embedded transmembrane helices.

    PubMed

    Dutagaci, Bercem; Sayadi, Maryam; Feig, Michael

    2017-02-04

    The heterogeneous dielectric generalized Born (HDGB) implicit membrane formalism is extended by the addition of a van der Waals dispersion term to better describe the nonpolar components of the free energy of solvation. The new model, termed HDGBvdW, improves the energy estimates in the hydrophobic interior of the membrane, where polar and charged species are rarely found and nonpolar interactions become significant. The implicit van der Waals term for the membrane environment extends the model from Gallicchio et al. (J. Comput. Chem. 2004, 25, 479) by combining separate contributions from each of the membrane components. The HDGBvdW model is validated with a series of test cases ranging from membrane insertion and pair association profiles of amino acid side chain analogs and transmembrane helices. Overall, the HDGBvdW model leads to increased agreement with explicit membrane simulation results and experimental data. © 2016 Wiley Periodicals, Inc.

  13. Integration of distributed energy resources. The CERTS Microgrid Concept

    SciTech Connect

    Lasseter, Robert; Akhil, Abbas; Marnay, Chris; Stephens, John; Dagle, Jeff; Guttromsom, Ross; Meliopoulous, A. Sakis; Yinger, Robert; Eto, Joe

    2002-04-01

    Evolutionary changes in the regulatory and operational climate of traditional electric utilities and the emergence of smaller generating systems such as microturbines have opened new opportunities for on-site power generation by electricity users. In this context, distributed energy resources (DER)--small power generators typically located at users' sites where the energy (both electric and thermal) they generate is used--have emerged as a promising option to meet growing customer needs for electric power with an emphasis on reliability and power quality. The portfolio of DER includes generators, energy storage, load control, and, for certain classes of systems, advanced power electronic interfaces between the generators and the bulk power provider. This white paper proposes that the significant potential of smaller DER to meet customers' and utilities' needs can be best captured by organizing these resources into MicroGrids.

  14. Deep Energy Retrofit Guidance for the Building America Solutions Center

    SciTech Connect

    Less, Brennan; Walker, Iain

    2015-01-01

    The U.S. DOE Building America program has established a research agenda targeting market-relevant strategies to achieve 40% reductions in existing home energy use by 2030. Deep Energy Retrofits (DERs) are part of the strategy to meet and exceed this goal. DERs are projects that create new, valuable assets from existing residences, by bringing homes into alignment with the expectations of the 21st century. Ideally, high energy using, dated homes that are failing to provide adequate modern services to their owners and occupants (e.g., comfortable temperatures, acceptable humidity, clean, healthy), are transformed through comprehensive upgrades to the building envelope, services and miscellaneous loads into next generation high performance homes. These guidance documents provide information to aid in the broader market adoption of DERs.

  15. Short-Term Test Results. Multifamily Home Energy Efficiency Retrofit

    SciTech Connect

    Lyons, James

    2013-01-01

    Multifamily deep energy retrofits (DERs) represent great potential for energy savings, while also providing valuable insights on research-generated efficiency measures, cost-effectiveness metrics, and risk factor strategies for the multifamily housing industry. This report describes the Bay Ridge project, a base scope retrofit with a goal of achieving 30% savings (relative to pre-retrofit), and a DER scope with a goal of 50% savings (relative to pre-retrofit). Findings from the short-term testing at Bay Ridge include air infiltration reductions of greater than 60% in the DER building; a hybrid heat pump system with a Savings to Investment Ratio (SIR) > 1 (relative to a high efficiency furnace) which also provides the resident with added incentive for energy savings; and duct leakage reductions of > 60% using an aerosolized duct sealing approach.

  16. van der Waals forces and electron-electron interactions in two strained graphene layers

    NASA Astrophysics Data System (ADS)

    Sharma, Anand; Harnish, Peter; Sylvester, Alexander; Kotov, Valeri N.; Neto, A. H. Castro

    2014-06-01

    We evaluate the van der Waals (vdW) interaction energy at zero temperature between two undoped strained graphene layers separated by a finite distance. We consider the following three models for the anisotropic case: (a) where one of the two layers is uniaxially strained, (b) the two layers are strained in the same direction, and (c) one of the layers is strained in the perpendicular direction with respect to the other. We find that for all three models and given value of the electron-electron interaction coupling, the vdW interaction energy increases with increasing anisotropy. The effect is most striking for the case when both layers are strained in the same direction where we observe up to an order of magnitude increase in the strained relative to the unstrained case. We also investigate the effect of electron-electron interaction renormalization in the region of large separation between the strained graphene layers. We find that the many-body renormalization contributions to the correlation energy are non-negligible and the vdW interaction energy decreases as a function of increasing distance between the layers due to renormalization of the Fermi velocity, the anisotropy, and the effective interaction. Our analysis can be useful in designing graphene-based vdW heterostructures which, in recent times, has seen an upsurge in research activity.

  17. Versatile van der Waals Density Functional Based on a Meta-Generalized Gradient Approximation

    NASA Astrophysics Data System (ADS)

    Peng, Haowei; Yang, Zeng-Hui; Perdew, John P.; Sun, Jianwei

    2016-10-01

    A "best-of-both-worlds" van der Waals (vdW) density functional is constructed, seamlessly supplementing the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation for short- and intermediate-range interactions with the long-range vdW interaction from r VV 10 , the revised Vydrov-van Voorhis nonlocal correlation functional. The resultant SCAN +r VV 10 is the only vdW density functional to date that yields excellent interlayer binding energies and spacings, as well as intralayer lattice constants in 28 layered materials. Its versatility for various kinds of bonding is further demonstrated by its good performance for 22 interactions between molecules; the cohesive energies and lattice constants of 50 solids; the adsorption energy and distance of a benzene molecule on coinage-metal surfaces; the binding energy curves for graphene on Cu(111), Ni(111), and Co(0001) surfaces; and the rare-gas solids. We argue that a good semilocal approximation should (as SCAN does) capture the intermediate-range vdW through its exchange term. We have found an effective range of the vdW interaction between 8 and 16 Å for systems considered here, suggesting that this interaction is negligibly small at the larger distances where it reaches its asymptotic power-law decay.

  18. Romanistik ohne Latein? Zu einer Empfehlung der Konferenz der Romanischen Seminare (Romance Studies without Latin? On a Recommendation from the Conference of Romance Seminars)

    ERIC Educational Resources Information Center

    Neumeister, Sebastian

    1973-01-01

    Reaction to a February 19, 1972 recommendation of the Konferenz der Romanischen Seminare der Bundesrepublik Deutschland und West-Berlins in Deutschen Romanistenverband'' (Conference of Romance Seminars of the Federal Republic of Germany and West Berlin of the German Association of Romance Philologists) to discontinue the Latin prerequisite for…

  19. Characterization of arginine kinase, anovel allergen of dermatophagoides farinae (Der f 20)

    PubMed Central

    Xing, Peng; Yu, Haiqiong; Li, Meng; Xiao, Xiaojun; Jiang, Congli; Mo, Lihua; Zhang, Min; Yang, Pingchang; Liu, Zhigang

    2015-01-01

    Objective: To characterize a novel allergen, the Dermatophagoides farinae-derived arginine kinase (Der f 20). Methods: The protein of Der f 20 was synthesized by genetic engineering approaches. The allergenicity of Der f 20 was tested by enzyme-linked immunosorbent assay and an airway allergy mouse model. Results: The Der f 20 gene was cloned andpresented in the Gene Bank with an accession number of AAP57094. The Der f 20 is an arginine kinase (AK), whichshowed a close relationship with D. pteronyssinus AK and Aleuroglyphusovatus AK. Western-blot and ELISA studies showed the IgE binding capacity of Der f 20 was 66.7% in the sera from 6 dust mite allergic patients. Immune inhibition assayresults showed the IgE cross-reactivity between Der f 20 and DME (Dust mite extract). Positive responses to Der f 20 were 41.2% as shown by skin prick tests in 17 DME-allergic patients. In vitro experimental results showed that Der f 20 induced Th2 cell differentiation and the expression of T cell Ig mucin domain molecule-4 (TIM4) in DCs. Conclusions; The Der f 20 protein is a novel subtype of thedust mite allergen. PMID:26885278

  20. Expression, purification and characterization of Der f 27, a new allergen from dermatophagoides farinae

    PubMed Central

    Lin, Jianli; Li, Meng; Liu, Yulin; Jiang, Congli; Wu, Yulan; Wang, Yuanyuan; Gao, Anjian; Liu, Zhigang; Yang, Pingchang; Liu, Xiaoyu

    2015-01-01

    The house dust mite (HDM), Dermatophagoidesfarinae (D. farina), is one of the most important indoor allergen sources and a major elicitor of allergic asthma; itscharacterization is important in the diagnosis and immunotherapy of mite allergen-relevant diseases. This study aims to characterize a novel allergen, the D. farinae-derived serpin (Der f 27). In this study, the total RNA of D. farinae was extracted, and the Der f 27 gene was cloned and expressed. The allergenicity of recombinant Der f 27 protein was determined by enzyme-linked immunosorbent assay, and Western-blotting with the sera of asthma patients, and skin prick test (SPT) in allergic human subjects. A r-Der f 27 allergic asthma mouse model was established. The cloned Der f 27 gene has been presented at the Gene Bank with an accession number of KM009995. The IgE levels of r-Der f 27 in the serum from r-Der f 27 SPT positive allergic patients were 3 folds more than healthy subjects. The Der f 27 SPT positive ratewas 42.1% in 19 DM-SPT positive patients. Airway hyperresponsiveness, serum specific IgE, and levels of interleukin-4 in the spleen cell culture supernatant were significantly increased in allergic asthma mice sensitized to r-Der f 27. In conclusion, Der f 27 is a new subtype of house mite allergen. PMID:26328010