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Sample records for surface proces 10-kev

  1. Supervisionens materiale og proces

    DEFF Research Database (Denmark)

    Jacobsen, Claus Haugaard

    2007-01-01

    Kapitlet handler om supervisionens materiale og proces, dvs. spørgsmålene om, hvilket materiale supervisanden skal medbringe til supervision, hvordan det skal fremlægges, og hvordan valg af materiale og metode gensidigt indvirker på hinanden og på supervisionsprocessen. Som de mest anvendte metoder...

  2. Onderzoek en/in methodiekontwikkeling, een veelstemmig proces

    Directory of Open Access Journals (Sweden)

    Hilde Vlaeminck

    2013-12-01

    Full Text Available Research and/on method-development, a multi-voiced processIn the past decade there is a growing – a renewed? – interest in the development of methods in social work. Research is supposed to play an essential role in this kind of projects. Practice teachers of university colleges are often in charge of it (rather than academic researchers because of their specific knowledge and their nearness with social work fields. This mixed role, being a teacher as well as a researcher and a developer, creates opportunities but evokes threats too. As a teacher he is monitoring methods on four levels: the technical-instrumental; the personal; the ethical; and the theoretical. As a supervisor he is acquainted with the daily professional practices and is familiar with casuistry. As a researcher he has to observe independently and critically from a meta-position to daily practices, to the underlying theories and assumptions. As a method developer he translates registered data in tools in order to systemize the interventions. He formulates limits and guidelines. A recent project in primary care in Flanders – used as a case in this article – describes the methodological choices in every phase. This project shows a remarkable number of stakeholders engaged with method development. Of course there is the duo of researcher and lecturer, but there are also: the method-practitioners; the method-users (clients; the method-supporting management, the method-policy and the method-referrals (colleague social workers as well as not-social workers belonging to the institutional network. They all have to play a significant role. Method development is a multi-voiced matter. Someone would say this is co-creation.Onderzoek en/in methodiekontwikkeling, een veelstemmig procesEr is een groeiende – een vernieuwde? – belangstelling voor methodiekontwikkeling in sociaal werk. Onderzoek wordt verondersteld daarin een essentiële rol te spelen. Praktijkdocenten van hogescholen

  3. Klinisk proces-eksperiment på Roskilde Amts Sygehus: Brugerdeltagelse og evidensbaseret udvikling

    DEFF Research Database (Denmark)

    2006-01-01

    at implementere en EPJ-løsning til dokumentation af den klinisk proces, som klinikerne udtrykker tilfredshed med, og som giver demonstrerede positive effekter i den kliniske praksis. • Projektet har demonstreret en mulig IT-strategi, hvor EPJ implementeres trinvist (i modsætning til den såkaldte ”big bang...

  4. [Basic cardiopulmonary resuscitation program for high school students (PROCES). Results from the pilot program].

    Science.gov (United States)

    Miró, Oscar; Jiménez-Fábrega, Xavier; Díaz, Núria; Coll-Vinent, Blanca; Bragulat, Ernest; Jiménez, Sònia; Espinosa, Gerard; Hernández-Rodríguez, José; García-Alfranca, Fernando; Alvarez, M Teresa; Salvador, Jordi; Millá, José; Sánchez, Miquel

    2005-01-15

    The PROCES (Programa de Reanimació Cardiopulmonar Orientat a Centres d'Ensenyament Secundari) program is aimed at teaching basic cardiopulmonary resuscitation (b-CPR) to teenagers within high school. Our aim was to analyze the results obtained from the pilot program. PROCES was splitted in 7 sessions: 5 of them (5 hours) were taught by teachers at high school and 2 of them (4 hours, including how to perform b-CPR) were taught by emergency physicians. To assess the degree of students' learning, they were administered a 20-question test before and after the program. Epidemiological characteristics and students' opinions (all them were requested to rate the program from 0 to 10) were also collected. Students were 14 years-old in 38%, 15 in 38% and 16 or more in 24%. Before PROCES, the mean mark (over 20 points) was 8.5 (2.4). After PROCES, marks improved up to 13.5 (3.2) (p knowledge and skills in b-CPR, with no exceptions associated with teenagers' characteristics.

  5. Reformatio in peius administratīvo pārkāpumu procesā

    OpenAIRE

    Berķis, Kaspars

    2009-01-01

    Maģistra darbā ir pētīta reformatio in peius aizlieguma principa piemērošanas problemātika administratīvo pārkāpumu procesā. Darba gaitā ir analizētas Latvijas Administratīvo pārkāpumu kodeksa, Administratīvā procesa likuma un kriminālprocesuālās tiesību normas, kas satur reformatio in peius aizlieguma principu. Darba ietvaros īpaša uzmanība pievērsta administratīvo tiesu prakses izpētei attiecībā uz reformatio in peius aizlieguma principa piemērošanu administratīvo pārkāpumu lietu izsk...

  6. The hydrothermal upgrading process (HTU) for biomass liquefaction; Het hydrothermal upgrading proces (HTU) voor biomassa liquefactie

    Energy Technology Data Exchange (ETDEWEB)

    Naber, J.E. (ed.) [Biofuel, Heemskerk (Netherlands)

    2001-07-01

    The HTU process has been investigated in 1981-1988 at the Shell Laboratory in Amsterdam, as a reaction to the two oil crises of 1973 and 1980. Due to the commercial circumstances in the late eighties, the research on the promising HTU technology was discontinued with only a few hundred hours of continuous bench-scale operation. While most of the critical elements of the technology were demonstrated in principle, many important data were lacking for a reliable design of the first (semi-) commercial applications, as well as a good understanding of the fundamental backgrounds, the product properties and possibilities/aspects of scaling up. Therefore the purpose and envisaged result of this project is a validated process on pilot plant scale, for a reliable design of the first commercial demonstration(s). Next to fundamental investigations of conversion mechanisms, process dynamics, thermodynamics of the multi-phase system and the water treating, the installation and continuous operation of an integrated pilot plant plays a central role in the project. The latter as well as the pressurizing of the biomass feed were identified as Go/No Go elements. With parallel research on e.g. reactor engineering and high pressure pumps, the HTU process can be scaled-up with confidence to throughputs of 10,000+ tons biomass/year. The pilot plant will be able to produce sufficient product to enable thorough research on various product applications and possibly the further upgrading by hydrodeoxygenation to 'green' transport fuels and/or premium ethylene cracker feedstock. The principle of this upgrading was also established in the R and D at the Shell Laboratory. [Dutch] Het HTU proces is in de jaren 1981-1988 onderzocht op het Shell Laboratorium in Amsterdam, als reactie op de twee olie crises van 1973 en 1980. Door de commerciele omstandigheden in het latere deel van de tachtiger jaren is de tot dan toe veelbelovende ontwikkeling van de HTU technologie vroegtijdig

  7. Nitrogenfiksering som en episodisk proces i opstrømnings-området i det østlige tropiske Stillehav

    DEFF Research Database (Denmark)

    Christensen, Jens Tang

    organismer i en lang række områder, hvor man hidtil ikke troede nitrogenfiksering forekom, og det globale kvælstofregnskab er kommet i bedre balance. Næringsrige opstrømnings-områder, som Humboldt-strømmen langs Chile og Peru, har indtil for nylig ikke været steder, hvor man anså denne proces...

  8. Návrh procesů pro společnost poskytující IT služby s ohledem na ISMS a ITSM

    OpenAIRE

    Haller, Martin

    2012-01-01

    Diplomová práce se zabývá návrhem procesů pro skutečnou společnost poskytující služby v oblasti informačních technologií. Výsledkem práce jsou modely navržených procesů, včetně návrhu potřebného informačního systému a vyhodnocení souladu navržených procesů oproti řadě norem ISO/IEC 27000 a ISO/IEC 20000. The goal of this diploma thesis is to design processes for existing ICT company mainly providing services. This work contains models of the designed processes and proposes convenient infor...

  9. Nepilngadīgās personas tiesības administratīvajā procesā.

    OpenAIRE

    Rubīna-Šinkuna, Gita

    2011-01-01

    Darba tēma – „Nepilngadīgās personas tiesības administratīvajā procesā.” Darba mērķis bija izpētīt nepilngadīgās personas tiesības administratīvā procesa tiesisko regulējumu, kā arī pamatojoties uz pētījuma rezultātiem, izstrādāti priekšlikumi normatīvo aktu pilnveidošanai. Izvirzītā mērķa sasniegšanai autore izvirzīja šādus darba uzdevumus: 1. Noskaidrot un analizēt nepilngadīgās personas tiesības administratīvā procesa normatīvo regulējumu; 2. Noskaidrot nepilngadīgās personas proc...

  10. Využití Balanced ScoreCard k měření výkonnosti procesů agentury CzechTrade

    OpenAIRE

    Achrerová, Gabriela Bc.

    2007-01-01

    Teoretická část: měření výkonnosti procesů v systémech managementu jakosti dle ISO 9001:2000 Aplikační část: charakteristika agentury, procesy agentury, stávající metodika Balanced ScoreCard, návrh nové metodiky Balanced ScoreCard v návaznosti na novou strategii

  11. Sustainable transition by HTU. An outline of the score of the HTU-process for sustainability aspects; Duurzame transitie met HTU. Een verkenning van de score van het HTU-proces op duurzaamheidsaspecten

    Energy Technology Data Exchange (ETDEWEB)

    Croezen, H.J.; Kampman, B.E.

    2005-04-15

    Insight is given in the sustainable aspects of the HTU-process (hydrothermal upgrading) for the production of biofuels from wet biomass and organic residues. By means of the HTU-process a reduction of 2.5 - 4.5 Mton CO2 emission can be realized in 2020. For the year 2040 a reduction of 15-30 Mton can be expected. [Dutch] Biofuel BV werkt aan de ontwikkeling van het HTU-proces (hydrothermal upgrading), met als doel om in de toekomst een biobrandstof uit natte biomassa te produceren. In het HTU-proces wordt biomassa bij hoger temperatuur en druk omgezet in 'biocrude', waaruit vervolgens een transportbrandstof kan worden geproduceerd. CE heeft, in opdracht van Biofuel, een duurzaamheidsanalyse van dit proces uitgevoerd. Uitgangspunt daarvoor was het gebruik van natte organische reststromen als grondstof. Deze stromen kunnen met het HTU-proces worden verwerkt, terwijl ze in de huidige praktijk van weinig waarde zijn. De berekeningen laten zien dat met deze technologie ca. 2,5 - 4,5 Mton CO2-reductie per jaar kan worden bereikt in 2020, indien de verdere ontwikkeling van het proces en de marktintroductie verloopt zoals Biofuel op dit moment verwacht. In de jaren erna kan de productiecapaciteit vervolgens verder worden uitgebreid, zodat voor 2040 een CO2-reductie van 15-30 Mton per jaar wordt verwacht. Het proces maakt optimalisatie van afvalverwerking en reststoffen verwijdering mogelijk. Bij verwerking van reststromen zullen de ecologische aspecten beperkt zijn. Er vindt geen ruimtebeslag plaats, waardoor ook geen sprake is van invloed op biodiversiteit of van concurrentie met voedselgewassen. Wat betreft de sociaal economische invloeden biedt het HTU-proces in principe het voordeel dat het proces landen zonder eigen olievoorraden in staat stelt om voertuig brandstoffen uit reststromen - tegen relatief lage kosten - te maken.

  12. Resource-efficient proces chains to manufacture patient-specific prosthetic fingers

    Directory of Open Access Journals (Sweden)

    Hagedorn-Hansen, D.

    2016-05-01

    Full Text Available The high cost of quality prostheses, together with the lack of trained prosthetists, makes it challenging to obtain prosthetic devices in developing communities. Modern 3D digitising techniques and additive manufacturing (AM technologies are gaining popularity in the bio-medical industry and, in the case of prosthesis production, reduce the need for a trained prosthetist. The objective of this research was to develop a new resource-efficient process chain for the manufacturing of prosthetic fingers using additive manufacturing technologies, and to compare it with the traditional (Sculptor process chain. Fused deposition modelling (FDM, open-source FDM, 3-dimensional printing (3DP, and stereolithography (SLA were evaluated in terms of their costs, time, material usage, and aesthetic quality. The surface qualities produced with the different additive manufacturing technologies were also compared. The results showed that 3DP was the preferred technology and was the best candidate for the production of prosthesis in terms of cost, quality, and time for developing communities. SLA produced the highest aesthetic quality prosthesis, but was the most expensive. It was concluded that using the additive manufacturing technology process chain to produce prosthetic fingers is faster and more cost effective than the traditional method.

  13. Detection of organic residues on poultry processing equipment surfaces by LED-induced fluorescence imaging

    Science.gov (United States)

    Organic residues on equipment surfaces in poultry processing plants can generate cross- contamination and increase the risk of unsafe food for consumers. This research was aimed to investigate the potential of LED-induced fluorescence imaging technique for rapid inspection of stainless steel proces...

  14. Využití možností IoT pro reinženýring podnikových procesů

    OpenAIRE

    Hujňák, Vilém

    2017-01-01

    Bakalářská práce se zabývá problematikou reinženýringu podnikových procesů s využitím možností Internetu věcí. V práci je navržena metoda implementace IoT procesním způsobem a ověřena na případové studii procesu zajištění pohybu oprávněných osob ve firemních prostorách s vyžitím vícefaktorové autentizace. The bachelor's thesis deals with the issue of Business Process Reengineering using possibilities of the Internet of Things. The thesis describes a method for implementing IoT solutions in...

  15. APPLICATION OF THE X-RAY STRUCTURE ANALYSIS FOR IMPROVEMENT OF TECHNOLOGICAL PROCES- SES OF WIRE PRODUCTION AT BMZ

    Directory of Open Access Journals (Sweden)

    D. V. Kuznetsov

    2012-01-01

    Full Text Available The X-ray diffraction methods of qualitative and quantative analysis of phase composition of the brass coating, scale on the surface of brass wire, rod, patented wire, methods of determining the characteristics of the microstrains the lattice ferritic matrix pearlitic high-carbon steel, are explored.

  16. Inhibition of glycoxidative modification of proteins by some substances of natural origin / Substancje Pochodzenia Naturalnego o Najsilniejszych Właściwościach Hamujących Proces Glikooksydacji

    Directory of Open Access Journals (Sweden)

    Grzebyk Ewa

    2016-03-01

    Full Text Available Wstęp: Zaawansowane końcowe produkty glikacji (AGE i zaawansowane produkty utleniania białek (AOPP są głównymi produktami glikooksydacji u pacjentów z cukrzycą. Cel: Celem pracy było zidentyfikowanie substancji naturalnego pochodzenia o najsilniejszych właściwościach hamujących proces glikooksydacji spośród suplementów diety i leków dostępnych bez recepty na polskim rynku farmaceutycznym. Metody: Albumina wołowa (BSA, witamina C (VC, aminoguanidyna (A, kwercetyna (Q i zielona herbata (GT były badane in vitro podczas procesów glikacji, utleniania i glikooksydacji. Zmniejszenie stężenia AGE i AOPP w porównaniu z kontrolą dodatnią przyjęto jako marker efektywności zachodzących procesów. Wyniki: Tworzenie AGE było zredukowane w 72% przez VC i w co najmniej 43% przez pozostałe substancje w procesie glikacji. Stężenie AOPP było obniżone o 99% przez VC i w przynajmniej 40% przez pozostałe substancje badane w procesie utleniania. W przebiegu glikooksydacji tworzenie AGE/AOPP było obniżone odpowiednio w 61% przez Q w 97% przez A i przynajmniej o 49%/88% przez pozostałe substancje. Wnioski: Badane substancje wykazały zdolności hamujące glikację, utlenianie i glikooksydację białek w różnym stopniu w zależności od zastosowanego stężenia.

  17. Technological change as social proces

    DEFF Research Database (Denmark)

    Jamison, Andrew

    2004-01-01

    The article distinguishes between different meanings that technology has as well as the different 'roles' that technologies play in society. udfoldes tre forståelser af teknologisk forandring. Der sigtes på at fremstille forskellige meningsdannelser, som i sit samspil konstituerer et samfunds opf...

  18. Mål og proces

    DEFF Research Database (Denmark)

    Ladeby, Karin

    2013-01-01

    Abstract Since the preparation of the first Bologna Agreement on joint development of education in 1999 and the preparation of the Danish qualification certification in 2003, the development of the medium-term higher education has gone in the direction, where the students are assessed after...... chosen to examine how the opportunities for learning through self experience and personal development appear in students' reflection of their own reflection. Here I will use the Mezirows theory of trans formative learning and Jarvis model for learning The focus of the interviews are: 1. focus...... is the meaning of education, as shows itself to the interviewed 2. focus is on the images, as it gently forms . What metaphors can describe the meaning of what has been said? 3. focus is the personal resonance. What arouses the resonance in the students background as learners and as would-be therapist? 4. focus...

  19. Evaluation of quality of butter from different provenance Avaliação da qualidade de manteigas de diferentes procedências

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Donato Gonçalves

    2012-09-01

    Full Text Available Butter samples were evaluated for free fatty acids, peroxide value, cholesterol, and fatty acid composition focusing on the trans isomer and conjugated linoleic acid (CLA. Sixty six samples were analyzed. Thirty six were collected in Brazil, eighteen in France, and twelve in Argentina. Samples were evaluated by free fatty acids, peroxide value, total lipid, cholesterol and fatty acid composition. The free fatty acid content varied from 0.16 to 0.46 g.100 g-1 and the peroxides value levels from 0.35 to 1.80 meq.kg-1. The cholesterol content varied from 192.8 to 226.3 g.100 g-1 and the total lipid content varied from 81.8 to 86.8 g.100 g-1. The levels of saturated, monounsaturated, and polyunsaturated fatty acids varied from 43.86 to 52.74, from 21.65 to 23.34, and from 2.11 to 2.89 g.100 g-1, respectively. The conjugated linoleic acid (CLA content varied from 0.56 to 0.86 g.100 g-1 and the levels of total trans isomer varied from 2.18 to 3.81 g.100 g-1.As amostras de manteigas foram avaliadas através das análises de ácidos graxos livres, índice de peróxidos, colesterol e composição em ácidos graxos. Foram analisadas 66 amostras, sendo 36 de procedência brasileira, 18 francesas e 12 argentinas. As amostras brasileiras foram provenientes dos Estados do Rio Grande do Sul, Paraná, São Paulo, Minas Gerais e Goiás. As amostras foram avaliadas quanto aos teores de ácidos graxos livres, índices de peróxidos, lipídeos totais, colesterol e composição em ácidos graxos livre. Os teores de ácidos graxos livres variaram de 0,16 a 0,46 g.100 g-1 e os índices de peróxidos de 0,35 a 1,80 meq.kg-1. Os teores de colesterol variaram de 192,8 to 226,3 g.100 g-1 e os lipídios totais de 81,8 a 86,8 g.100 g-1.Os teores de ácidos graxos saturados, monoinsaturados e poli-insaturados variaram de 43,86 a 52,74, de 21,65 a 23,34 e de 2,11 a 2,89 g.100 g-1, respectivamente. Os teores de CLA variaram de 0,56 a 0,86 g.100 g-1 e os isômeros trans de 2

  20. Wood hydraulic characteristics in two provenances of Myracrodruon urundeuva Allemão (Anacardiaceae trees. Características hidráulicas da madeira em árvores de duas procedências de Myracrodruon urundeuva (Anacardiaceae.

    Directory of Open Access Journals (Sweden)

    Gabriela Trindade PIRES

    2016-12-01

    procedências de sementes. Hipotetizamos que há variação na condutividade hidráulica entre as árvores de duas procedências e que esta variação deve estar relacionada com a origem das sementes. Estudamos galhos de aproximadamente 2 cm de diâmetro, retirados de dez árvores, cinco de cada procedência. Utilizamos técnicas padrão para a anatomia da madeira. Os valores experimentais de condutividade hidráulica foram obtidos com o aparato de Sperry. O comprimento dos vasos não variou entre as procedências, portanto, esta característica não explica as variações encontradas na condutividade hidráulica. A maior condutividade hidráulica encontrada em IS pode ser explicada pelo maior diâmetro dos vasos quando comparados com aqueles de PE, além da maior porcentagem de vasos embolizados em PE. Ambas as características podem estar relacionadas ao genótipo, uma vez que, as árvores-mãe em IS podem estar adaptadas ao maior déficit hídrico de IS quando comparado com PE. Portanto, a maior condutividade hidráulica em IS pode ser uma estratégia para permitir uma distribuição mais eficiente de água na planta em um ambiente com maior estresse hídrico. Nossos resultados sugerem que diferentes procedências têm diferentes estratégias de uso de água. A menor densidade aparente da madeira de IS pode estar relacionada ao maior diâmetro do vaso.

  1. Morfometria e nervação foliar em procedências de erva-mate (Ilex paraguariensis A. St. Hill. (Aquifoliaceae = Morphometry and foliar venation in origins of maté (Ilex paraguariensis A. St. Hill. (Aquifoliaceae

    Directory of Open Access Journals (Sweden)

    Vânia Helena Techio

    2009-10-01

    Full Text Available O presente trabalho objetivou analisar a morfologia foliar morfometria e nervação foliar de procedências de erva-mate coletadas no Sul do Brasil e Argentina. Analisaram-se 30 folhas de cada procedência, obtendo-se cinco medidas (comprimento total da folha, largura máxima, comprimento desde a base até a largura máxima, comprimento do pecíolo e área e calculando-se dois índices (comprimento total sobre a largura máxima e comprimento desde a base até a largura máxima sobre o comprimento total da folha. Para anervação foliar, as folhas foram clarificadas por meio da técnica de diafanização. Os maiores e menores valores morfométricos foram, respectivamente, 118 e 67 mm para comprimento da folha, 51 e 34 mm para largura máxima, 78 e 42 mm para comprimento desde a base até alargura máxima, 16 e 10 mm para comprimento do pecíolo, 2,3 e 2 mm para comprimento sobre largura máxima e 0,65 e 0,6 para comprimento desde a base até a largura máxima sobre o comprimento da folha. Quanto à nervação foliar, não foram observadas diferenças entre as folhas das distintas procedências, as quais apresentaram nervação primária penada, nervação secundária semicraspedódroma, nervuras terciárias com percurso alternado e sinuoso, nervação quaternária reticulada, constituída por polígonos regulares e nervação de 5ª ordem dicotomizante.The present research aimed to evaluate the foliar morphology(morphometry and leaf venation of origins of maté collected in southern Brazil and Argentina. For the study of the morphometry, thirty leaves/plant were analyzed, and five measurements (leaf total length, maximum width, length from the base until maximum width, area and petiole length and two indices were obtained (total leaf length on maximum width and length from basis until maximum width on total leaf length. The leaves were clarified by the clarificationtechnique and examined in stereomicroscope. The highest and lowest values of leaf

  2. Crescimento e sobrevivência de duas procedências de Aspidosperma polyneuron em plantios experimentais em Bauru, SP. Growth and survival of two provenances of Aspidosperma polyneuron Müll. in experimental plantation, in Bauru, SP.

    Directory of Open Access Journals (Sweden)

    Aida Sanae SATO

    2008-06-01

    Full Text Available A exploração desordenada das matasnativas vem causando o esgotamento davariabilidade genética de muitas espécies de valoreconômico e ambiental. Desde a década de 1960,o Instituto Florestal de São Paulo vem desenvolvendoestudos pioneiros em conservação ex situ dealgumas espécies nativas ameaçadas e de interesseeconômico, como, por exemplo, Aspidospermapolyneuron, visando à conservação, ao melhoramentogenético e ao conhecimento do seu comportamentosilvicultural. Em 1964 foi implantado um experimentocom duas procedências de A. polyneuron: Bauru(SP e Alvorada do Sul (PR, em uma Unidade deConservação do Instituto Florestal, em Bauru/SP.Foi utilizado o delineamento de blocos ao acaso,com nove plantas por parcela, espaçamento 3 x 3 me seis repetições. Em 2006, foram avaliados odiâmetro à altura do peito (DAP, cm, altura total(HT, m, forma do fuste (F, volume cilíndricoindividual (VCi, m3, volume cilíndrico por hectare(VCha, m3 ha-1 e sobrevivência (S, %. Os resultadosdemonstraram que a procedência Bauru apresentoumaior produção volumétrica de madeira por hectare(VCha e que os valores das demais variáveis nãodiferiram estatisticamente entre as duas procedências.As informações obtidas neste estudo sãoimportantes para fornecer subsídios para avaliar aviabilidade de plantios comerciais e experimentaisde A. polyneuron visando à conservação e aomelhoramento genético desta espécie.The disorderly exploitation of nativeforests has caused the depletion of the geneticvariability of many species of economic andenvironmental value. Since the 1960 decade,the Forestry Institute of São Paulo has beendeveloping pioneering studies of ex situconservation of some endangered native treespecies and with economic interests, as for example,Aspidosperma polyneuron aiming the conservation,the tree breeding and the knowledge of thesilvicultural behavior. In 1964 an experiment withtwo provenances was implanted: A. polyneuron,Bauru (SP

  3. Comprehensive evaluation of dioxins and dioxin-like compounds in surface soils and river sediments from e-waste-processing sites in a village in northern Vietnam: Heading towards the environmentally sound management of e-waste

    OpenAIRE

    Go Suzuki; Masayuki Someya; Hidenori Matsukami; Nguyen Minh Tue; Natsuyo Uchida; Le Huu Tuyen; Pham Hung Viet; Shin Takahashi; Shinsuke Tanabe; Abraham Brouwer; Hidetaka Takigami

    2016-01-01

    The management of electronic waste (e-waste), which can be a source of both useful materials and toxic substances, depending on the processing method, is important for promoting material cycling. In this study, we used the dioxin-responsive chemical-activated luciferase gene expression (DR-CALUX) assay combined with gas chromatography–high-resolution mass spectrometry to evaluate the levels of dioxin-like compounds in surface soils and river sediments collected in and around an e-waste-proces...

  4. Território, certificação de procedência e a busca da singularidade: o caso do Café do Cerrado DOI:10.5007/2175-7984.2011v10n19p305

    Directory of Open Access Journals (Sweden)

    Antonio César Ortega

    2011-10-01

    Full Text Available Este artigo analisa a experiência do arranjo produtivo territorial organizado pelos cafeicultores do oeste do estado de Minas Gerais (Brasil, que, por meio de suas associações de produtores municipais, constituíram o Conselho das Associações dos Cafeicultores do Cerrado Mineiro (Caccer, que obteve, em 2005, o reconhecimento da Indicação Geográfica de seu café, e pôde passar a emitir a Certificação de Procedência Café do Cerrado. Desde então, cabe ao Caccer atestar a qualidade da produção de seus filiados que atendam às especificações exigidas por aquela certificação. O Café do Cerrado constituiu-se, assim, na primeira região de origem produtora de café demarcada do país. O sucesso daquela cafeicultura está ligado à constituição de um arranjo produtivo territorial rural, bastante institucionalizado, cuja inserção nos mercados nacional e global é cada vez mais expressiva. Porém, há que se reconhecer que esse processo tem causado diferenciação entre os produtores, entre os que têm e os que não têm conseguido acompanhar as exigências estabelecidas pela certificação de origem.

  5. Densidade básica e dimensões celulares da madeira de Balfourodendron riedelianum em função da procedência e posição radial. Basic density and wood cells dimensions of Balfourodendron riedelianum depending on the provenance and radial position.

    Directory of Open Access Journals (Sweden)

    Israel Luiz de LIMA

    2011-12-01

    Full Text Available O objetivo deste trabalho foi estudar a variação radial da densidade básica e das dimensões celulares da madeira de procedências de Balfourodendron riedelianum plantadas em Luiz Antonio–SP. Mudas de três procedências (Alvorada do Sul, Gália e Bauru foram plantadas em Luiz Antonio–SP, utilizando-se seis repetições em delineamento experimental de blocos casualizados. Após 24 anos do plantio, abateram-se dezoito árvores, seis de cada procedência. De acordo com os resultados, pode-se concluir que a densidade básica,o diâmetro de vasos e a altura de raio foram influenciados pela procedência. Foi observada uma relação positiva entre comprimento das fibras, espessura da parede das fibras, comprimentos dos vasos, diâmetro dos vasos e frequência de vaso com a posição radial e uma relação negativa entre a largura e a frequência de raio com a posição radial.This study aimed to investigate the effect of provenances on some woodproperties of Balfourodendron riedelianum. Seedlings of three provenances (Alvorada do Sul,Gália and Bauru were planted in Luiz Antonio–SP using randomized block design with six replicates. After 24 years of planting, eighteen trees, six of each provenance, were fell. The results revealed that basic density, vessel diameter and ray height were influenced by the provenances. A positive relationship was found among fiber length, fiber wall thickness, vessel length; vessel diameter and vessel frequency with radial position and a negative relationship between width and ray frequency with the radial position.

  6. The effect of oxidative modifications of amino acid residues in the active center of tyrosinase on the process of graying = Wpływ oksydacyjnych modyfikacji reszt aminokwasowych w centrum aktywnym tyrozynazy na proces siwienia

    Directory of Open Access Journals (Sweden)

    Anna Cwynar

    2015-08-01

    2 Katedra Pediatrii, Hematologii i Onkologii, Collegium Medicum w Bydgoszczy   Summary Reactive oxygen species (ROS are molecules that form during  physiological processes of cellular metabolism. Production of ROS in the organism is strictly controlled by the system of numerous anti-oxidative mechanisms. Insufficiency of defense systems and an increase in the level of free radicals leads to disturbances of the oxidative-antioxidative balance, and consequently, to generation of oxidative stress. Many observations indicate that the process which underlies graying is oxidative stress induced by hydrogen peroxide. Milimole concentrations of hydrogen peroxide (H2O2 are accumulated within gray hairs. Its presence inhibits transformation of tyrosine to melanin through the inactivation of the enzyme tyrosinase. The cause of an increase in H2O2 level is most probably a decrease in activity of catalase (CAT responsible for its detoxication. This is a significant step forward, since the studies have indicated that another enzyme, called pseudocatalase, may prevent generation of gray hair. Scientists are working on obtaining effective inhibitors of the process of graying that could in the future serve as medicines preventing premature graying. Finding the mechanisms responsible for this process creates possibilities for developing new objectives for pharmacological therapy. The aim of this work is to present current reports concerning the problem of graying and a potential participation of oxidative stress in the course of this process.   Streszczenie Reaktywne formy tlenu (RFT są molekułami powstającymi podczas fizjologicznych procesów metabolizmu komórkowego. Produkcja RFT w organizmie podlega ścisłej kontroli przez system licznych mechanizmów antyoksydacyjnych. Niewydolność systemów obrony oraz wzrost poziomu wolnych rodników prowadzi do zaburzeń równowagi oksydacyjno-antyoksydacyjnej, a w konsekwencji do generacji stresu oksydacyjnego. Wiele obserwacji

  7. Influence of Experimental Conditions on Deposition of Silver Nanoparticles Onto Surface of Graphene Oxide / Wpływ Warunków Eksperymentalnych Na Proces Osadzania Nanocząstek Srebra Na Powierzchni Tlenku Grafenu

    Directory of Open Access Journals (Sweden)

    Wojnicki M.

    2015-12-01

    Full Text Available Present work describes the influence of silver nanoparticles precursor form as well as the impact of graphene oxide initial concentration on deposition of the silver nanoparticles onto graphene oxide. Borane dimethylamine complex (DMAB was used as the reducing agent. It was observed that application of silver ammonia complexes as the silver nanoparticles precursor as well as alkaline solution effect in higher quantity of deposited AgNPs in comparison to deposition process with the use of silver(I nitrate in acidic solution.

  8. Variabilidade entre procedências de paricá Schizolobium parahyba var amazonicum (Huber ex Ducke Barneby plantadas no município de Colares - Pará Variability among Schizolobium parahyba var. amazonicum (Huber ex Ducke Barneby provenances planted in the municipality of Colares - PA

    Directory of Open Access Journals (Sweden)

    Selma Toyoko Ohashi

    2010-03-01

    Full Text Available O estudo envolveu quatro procedências de paricá (Schizolobium parahyba var. amazonicum plantadas no município de Colares-PA, seguindo um delineamento experimental em blocos ao acaso com cinco repetições. As características estudadas foram: sobrevivência, altura da planta, diâmetro a 1,30m do solo (DAP, altura e diâmetro da copa, percentagem de plantas atacadas e tipo de casca. A avaliação foi efetuada aos três anos de idade. Foram encontradas diferenças entre procedências para a sobrevivência e crescimento em altura da planta e DAP, não tendo sido encontradas diferenças para as características de altura da copa, diâmetro da copa, percentagem de plantas atacadas e tipo de casca. A procedência de maior sobrevivência foi Belterra que diferiu das demais ao nível de 5% de significância. Para o crescimento em Altura da planta e DAP, as procedências Belterra, Ji-Paraná e Alta Floresta foram estatisticamente iguais entre si, diferindo de Brasiléia que apresentou o menor desenvolvimento. As procedência Belterra, Alta Floresta e Ji-Paraná podem ser recomendadas para o uso em programas de reflorestamento e sistemas agroflorestais para esta região. O coeficiente de correlação de Spearman indicou alta associação entre as variáveis de produção e a latitude, indicando que as procedências de latitudes mais baixas tendem a ter um maior desenvolvimento, entretanto, devido este estudo ter envolvido somente uma pequena amostra dentro da ampla área de distribuição da espécie, é aconselhável ampliar o trabalho de prospecção e coleta para melhor explorar a variabilidade no programa de melhoramento genético com a espécie.The study involved four three-year-old provenances of Schizolobium parahyba var. amazonicum planted in the municipality of Colares-Pará, following an experimental design of randomized blocks with five replications. The studied characteristics were: survival, plant height, diameter at 1.30 m from the

  9. Implementacija metode 5S v proces proizvodnje

    Directory of Open Access Journals (Sweden)

    Alojz Gorše

    2016-03-01

    Full Text Available Abstract: Research Question (RQ: The following research tries to show how the introduction of 5S methodology of work affects the production process itself, where the greatest changes are shown and how they are reflected in performance indicators. Purpose: The purpose of this project is to examine the existing methods and their application in practice as well as show the logic of actions we introduce in a particular process by using the 5S method. We will try to compare all the information using a practical example of company X. The results obtained are the basis for further improvements in an analyzed company. Method: We expect positive results in terms of certain improvements in the working environment within the company, as well as the opportunity for improvement in terms of increased efficiency and, consequently, more profit. Results: The results can represent the basis for achieving eve n better work in other processes in the studied company. It is very important to identify all the key activities that are important in generating profits while all the rest are eliminated from the process. Organization: The 5S model is applicable to all levels of the organization so it can be experienced by the highest levels of management in running a business. Society: The impact of the model will surely be seen by employees as they are offered a model after which they will work well, quickly, safely and without loss of time, which in today's world means competitive advantage. Originality: The research work represents an important contribution to the implementation of the 5S model in the company and to the positive things it brings. Limitations/Future Research: The survey as a case study was done in only one organization, in which they were implemented all phases of the method. In the direction of further research it is reasonable to make a quantitative analysis of the increase in profit, increase employee satisfaction analysis, to determine the reduction of the environmental impact, etc.

  10. #IAmMan: A Communication Proces

    OpenAIRE

    de Carné de Carnavalet, Caroline Marie Karine; Ricka, Sille Holm; Langlois, Magali; Nau, Frauke

    2016-01-01

    The purpose of this project is to test and analyse the reception of a campaign within the intended target audience. After having acquired preknowledge about the target group and area of subject, the project use the method of conducting qualitative interviews for gathering empirical knowledge about the reception within the target audience. After doing so the project takes a more theoretical analytical approach by applying Schröder’s Multidimensional model to our new empirical knowledge. The pr...

  11. Utilsigtet blindhed i den diagnostiske proces

    DEFF Research Database (Denmark)

    Andersen, Amalie Middelboe; Friis, Jan K B; Østergaard, Lars J

    2017-01-01

    When engaged in a demanding task of visual perception we tend to become blind to stimuli, which are not part of our primary task - a bias known as inattentional blindness. This article studies inattentional blindness in radiologists' interpretation of scans. Furthermore, it is discussed, how...

  12. Sport and APA: proces of possible diffusion

    Directory of Open Access Journals (Sweden)

    Hana Válková

    2011-03-01

    Full Text Available Relation between Adapted Physical Activity (APA are described in the article. Recent sport professions as so as professions related to sports are formulated. "Coach" profession is defined with more details, the term "sport of persons with disability" is explained, too. On the bases of personal experience the APA domain which every coach can be touched are presented. Events which recent coaches, sports clubs in Czech Republic participated in are added. The basic questions of EUSAPA project are answered: regular sport and APA are blended together. Diffusion of sport and APA can become good platform for inclusion in life span context. Coaches should be informed about basic principles of APA according the level of connection (humanitarian domain - coaches in sports of disabled, the type of sport (relation to general sport and performance level (recreation - top competitive. The topic APA should be included on adequate level in education courses of coaches. The practice in sport activities of people with disability has to be involved.

  13. Synthesis and Optimization of a Methanol Proces

    DEFF Research Database (Denmark)

    Grue, J.; Bendtsen, Jan Dimon

    2003-01-01

    of reaction. The resulting model consists of a system of DAEs. The model is compared with rigorous simulation results from Pro/II and good agreement is found. The process is optimized followed by heat integration and large differences in the operating economy of the plant can be observed as a result hereof...

  14. Tolerância de rizóbios de diferentes procedências ao zinco, cobre e cádmio Tolerance of rhizobia genera from different origins to zinc, copper and cadmium

    Directory of Open Access Journals (Sweden)

    Alexandre Matsuda

    2002-03-01

    Full Text Available Sessenta estirpes/isolados dos gêneros Bradyrhizobium, Rhizobium, Sinorhizobium, Mesorhizobium e Azorhizobium, procedentes de diferentes locais (Mata Atlântica, Amazônia, culturas agrícolas e experimentos com metais pesados e de espécies hospedeiras pertencentes às subfamílias Papilionoideae, Mimosoideae e Caesalpinoideae, foram avaliadas quanto à tolerância a Zn, Cu e Cd em meio YMA modificado pela adição de tampões biológicos (HEPES e MES e suplementados com Cu (0 a 60 mg L-1, Cd (0 a 60 mg L-1 e Zn (0 a 1.000 mg L-1. Mediante padrões de crescimento atribuídos às culturas nas diferentes concentrações dos metais, avaliaram-se as concentrações máximas toleradas e as doses tóxicas destes metais para redução de crescimento em 25% (DT25 e 50% (DT50. Não houve influência da procedência na concentração máxima de metal tolerada. A ordem de sensibilidade aos metais, considerando-se as concentrações máximas toleradas, foi Azorhizobium > Rhizobium = Mesorhizobium = Sinorhizobium > Bradyrhizobium. A DT25 e a DT50 foram úteis para diferenciarem estirpes/isolados de um mesmo gênero, que atingiram a mesma concentração máxima tolerada a Zn, Cu e Cd. A ordem de toxicidade dos metais estudados foi Cu > Cd > Zn.Sixty strains/isolates of the genera Bradyrhizobium, Rhizobium, Sinorhizobium, Mesorhizobium and Azorhizobium, isolated from different hosts (legume subfamilies: Papilionoideae, Mimosoideae and Caesalpinoideae and location (Atlantic Forest, Amazon region, crop plantings and heavy metal experiments, were evaluated for Zn, Cu and Cd tolerance in YMA medium modified by the addition of biological buffers (HEPES and MES and supplemented with Cu (0 to 60 mg L-1, Cd (0 to 60 mg L-1, and Zn (0 to 1,000 mg L-1sulphates. Growth standards were applied to evaluate rhizobia cultures growth at different metal concentrations, allowing evaluation of highest tolerated concentrations of Zn, Cu, and Cd and the toxic doses

  15. Provenance and family variation of Pinus caribaea var. hondurensis from Guatemala and Honduras, grown in Brazil, Colombia and Venezuela Variação em procedências e famílias de Pinus caribaea var. hondurensis da Guatemala e Honduras, testadas no Brasil, Colômbia e Venezuela

    Directory of Open Access Journals (Sweden)

    Vicente Pongitory Gifoni Moura

    2001-02-01

    Full Text Available Pinus caribaea var. hondurensis (Sénécl Barr. & Golf. is a tropical pine that naturally occurs in lowland areas of Belize, El Salvador, Guatemala, Honduras, Nicaragua, and eastern Mexico. It has been one of the most studied tropical pines and the one with the most commercial importance in Brazil. The objective of this work was to select the best provenances for plantations and best trees in families for the establishment of seed orchards. For that a trial with five provenances and 47 open-pollinated families was planted near Planaltina, Federal District, in the Cerrado Region of Brazil. The provenances tested were Poptun (Guatemala, Gualjoco, Los Limones, El Porvenir and Santa Cruz de Yojoa (Honduras and assessed at 12 years of age. Poptun and Gualjoco had larger volume, and Los Limones and El Porvenir the lowest incidence of forks and foxtails. Individual tree heritabilities for volume, stem form and branch diameter were 0.34, 0.06, and 0.26 respectively. More than 90% of the trees had defects, common in unimproved P. caribaea. Selection criteria for quality traits need to be relaxed in the first generation of breeding to allow for larger genetic gains in productivity. Results from this test compared with P. caribaea var. hondurensis trials in other Brazilian, Colombian and Venezuelan sites suggest that provenance x site and family x site interactions are not as strong as in other pine species.Pinus caribaea var. hondurensis (Sénécl Barr. & Golf. é uma espécie tropical que ocorre naturalmente nas terras baixas de Belize, El Salvador, Guatemala, Honduras, Nicarágua e no leste do México. Esta espécie tem sido uma das mais estudadas entre os pinos tropicais e uma das mais importantes comercialmente no centro e norte do Brasil. O objetivo deste trabalho foi selecionar as melhores procedências para plantios e também as melhores árvores dentro de famílias para o estabelecimento de pomares de semente. Para isso, um experimento com cinco

  16. Basic specific gravity and anatomy of Peltophorum dubium wood as a function of provenance and radial position. Densidade aparente e anatomia da madeira de Peltophorum dubium em função da procedência e posição radial.

    Directory of Open Access Journals (Sweden)

    Israel Luiz de LIMA

    2015-06-01

    Full Text Available We studied the wood of Peltophorum dubium (Spreng. Taub. (Fabaceae, popularly known in Brazil as canafístula, from two seed provenances with different climates. The trees were planted in a third place and cut when 28 years old. Based on differences in seed origins, we hypothesized that some differences would be observed in wood density and anatomical features between provenances and that the radial variation pattern would also differ. However, we did not observe any differences in basic specific gravity or anatomical features between the provenances, which may partly be explained by the conservative nature of wood compared with the external characteristics more susceptible to environmental stresses. In fact, based on the literature and our previous findings, radial variation in P. dubium was similar to that found in many native species, including, for example, increase in basic specific gravity, length and wall thickness of the fibers, increase in vessel diameter and decrease in vessel frequency toward the bark. Based on our results, it can be concluded that P. dubium has high plant adaptability in different locations and that consistency in the quality of its wood can be maintained between provenances, with concomitant implications for both production and use. Estudamos a madeira de Peltophorum dubium (Spreng. Taub. (Fabaceae, popularmente conhecida no Brasil como canafístula, a partir de duas procedências de sementes com diferentes climas. As árvores foram plantadas em um terceiro lugar e cortadas aos 28 anos. Com base nas diferentes origens das sementes, hipotetizamos que diferenças seriam observadas na densidade aparente e características anatômicas da madeira entre as procedências e que o padrão de variação radial também diferisse. No entanto, não foram observadas quaisquer diferenças na densidade aparente ou nas características anatômicas entre as procedências, o que pode em parte ser explicado pela natureza conservativa

  17. Ciclagem de nutrientes em Acacia mearnsii de wild. V. Quantificação do conteúdo de nutrientes na biomassa aérea de Acacia mearnsii de wild. Procedência australiana Nutrient cycling in Acacia mearnsii de wild. V. Quantification of nutrient contents in the above-ground biomass of australian provenance of Acacia mearnsii de wild

    Directory of Open Access Journals (Sweden)

    Marcos Vinicius Winckler Caldeira

    2000-12-01

    Full Text Available No presente trabalho foi quantificado o conteúdo de nutrientes na procedência Australiana Bodalla de Acácia-negra (Acacia mearnsii De Wild., aos 2,4 anos de idade. A procedência encontra-se estabelecida em solo de baixa fertilidade, com acidez elevada e localizado na Fazenda Menezes, no Distrito de Capão Comprido, município de Butiá-RS, pertencente à Empresa Florestal Agroseta S.A.. Foi selecionado um total de nove árvores para comporem as amostras. A amostragem destrutiva constituiu na individualização dos compartimentos da biomassa aérea (folhas, galhos vivos, galhos mortos, casca e madeira visando à determinação da matéria seca e do conteúdo de nutrientes. As quantidades de nutrientes contidos na biomassa aérea total da procedência Bodalla foram de 182,1kg ha-1 de N; 8,2kg ha-1 de P; 104,4kg ha-1 de K; 66,7kg ha-1 de Ca; 16,1kg ha-1 de Mg e 10,0kg ha-1 de S. Na procedência Bodalla, 57,4% da matéria seca foi alocada para folhas, galhos vivos e galhos mortos, contento 74% do N; 72,1% do P; 63% do K; 68,5% do Ca, 69,3% do Mg e 74,1% do S do total existente na parte aérea. O componente fuste ( casca e madeira acumulou 26% do N; 27,9% do P; 37% do K; 31,5% do Ca; 30,7% do Mg e 25,8% do S.Nutrient contents of 2.4 years old black wattle (., from Bodalla Australian provenance, were quantified. This provenance was established on soils of low fertility and high acidity, at Menezes Farm of Agroseta S.A. Forest CompAcacia mearnsii De Wildany in the Capão Comprido District, municipality of Butiá-RS. A total of nine trees were selected to form the sample. The destructive sampling was constituted in the individualization of compartments of above-ground biomass (leaves, live branches, dead branches, bark and wood to determine dry matter and nutrient contents. The quantity of total nutrients in the above-ground biomass from Bodalla provenance was 182.1kg ha-1 of N; 8.2kg ha-1 of P; 104.4kg ha-1 of K; 66.7kg ha-1 of Ca; 16.1kg ha-1 of

  18. Surface Water & Surface Drainage

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This data set contains boundaries for all surface water and surface drainage for the state of New Mexico. It is in a vector digital data structure digitized from a...

  19. Conteúdo e exportação de micronutrientes em acácia-negra (Acacia Mearnsii De Wild. procedência batemans bay (Austrália Content and exportation of micronutrients in black wattle (Acacia Mearnsii de wild. of Australian batemans bay provenance

    Directory of Open Access Journals (Sweden)

    Marcos Vinicius Winckler Caldeira

    2003-02-01

    Full Text Available O objetivo do presente trabalho foi estimar o conteúdo e a exportação de micronutrientes (Mn, B, Cu, Zn e Fe e o Na nos diferentes componentes de árvores de um povoamento de acácia-negra (Acacia mearnsii De Wild., procedência australiana Batemans Bay, com 2,4 anos de idade, em Butiá-RS (Brasil. A biomassa total estimada foi de 36.155 kg/ha, apresentando distribuição de 46,0, 20,0, 19,5, 12,0 e 3,0%, na madeira do lenho, nas folhas, nos galhos vivos, na casca e nos galhos mortos, respectivamente. A proporção de micronutrientes acumulados na biomassa dos componentes da árvore foram 43,76% nas folhas, 26,94% na madeira do tronco, 19,56% nos galhos vivos, 7,21% na casca e 2,54% nos galhos mortos. A quantidade estimada de micronutrientes contidos na biomassa acima do solo foi 10,4 kg/ha, acumulados da seguinte forma: Na (58,84%, Fe (21,79%, Zn (9,16%, B (4,09%, Mn (4,59% e Cu (1,54%. A casca e a madeira do lenho acumulou Na (21,47%, Fe (6,71%, Mn (2,11%, Zn (1,66%, B (1,58% e Cu (0,63%. A copa (folhas e galhos vivos e mortos acumularam Na (37,36%, Fe (15,07%, Zn (7,49%, B (2,53%, Mn (2,48% e Cu (0,91%. A exploração intensiva de áreas com a procedência Batemans Bay gera suspeitas de possíveis ocorrências de deficiências nutricionais de Na nas rotações futuras, tornando necessário o emprego de fertilizantes para manter a produtividade do sítio.This study aimed to estimate the content and exportation of micronutrients (Mn, B, Cu, Zn e Fe and Na in different tree components of black wattle (Acacia mearnsii De Wild. forest of Batemans Bay Australian provenance, 2.4 years old in Butiá, RS, Brazil. The total biomass found was 36,155 kg/ha, thus distributed: 46.0%; 20.0%; 19.5%; 12.0% and 3.0%, spread in the wood of the stem, leaves, live branches, bark and dead branches, respectively. The proportion of the micronutrients accumulated in the biomass of the components were: leaves (43.76%, wood of the stem (26.94%, live branches (19

  20. Genetic evaluation and deviance analysis in an unbalanced provenance and progeny test of maté Avaliação genética e análise de deviance em um teste desbalanceado de procedência e progênie de Ilex paraguariensis

    Directory of Open Access Journals (Sweden)

    José Alfredo Sturion

    2010-10-01

    -pagination:widow-orphan; font-size:10.0pt; mso-bidi-font-size:12.0pt; font-family:Arial; mso-fareast-font-family:"Times New Roman"; font-weight:bold;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} -->

    Em um teste combinado de procedência e progênie de erva-mate (Ilex paraguariensis A. St. Hil., os efeitos aleatórios do modelo foram testados pelo teste da razão de verossimilhança (LTR. Os dados referem-se
    ao peso de biomassa foliar obtido aos seis anos de idade, por ocasião da terceira poda, em um teste com
    sete procedências e 140 progênies de meios-irmãos instalado no delineamento de blocos ao acaso, com dez repetições de parcelas lineares com seis plantas no espaçamento de 3 m x 2 m. A análise de deviance (Anadev foi realizada e as seguintes conclusões foram obtidas: os componentes de variância associados a todos os efeitos aleatórios do modelo e respectivos coeficientes de determinação (herdabilidades dos efeitos genéticos aditivos, dos efeitos de parcela e dos efeitos de procedência foram significativamente diferentes de zero, indicando que existe variabilidade genética significativa a ser explorada pelo melhoramento, tanto entre como dentro de populações naturais.

    doi: 10.4336/2010.pfb.30.62.157

  1. Minimal surfaces

    CERN Document Server

    Dierkes, Ulrich; Sauvigny, Friedrich; Jakob, Ruben; Kuster, Albrecht

    2010-01-01

    Minimal Surfaces is the first volume of a three volume treatise on minimal surfaces (Grundlehren Nr. 339-341). Each volume can be read and studied independently of the others. The central theme is boundary value problems for minimal surfaces. The treatise is a substantially revised and extended version of the monograph Minimal Surfaces I, II (Grundlehren Nr. 295 & 296). The first volume begins with an exposition of basic ideas of the theory of surfaces in three-dimensional Euclidean space, followed by an introduction of minimal surfaces as stationary points of area, or equivalently

  2. Substanciniai ir procedūriniai praktinio racionalumo aspektai

    OpenAIRE

    Norkus, Zenonas

    2008-01-01

    The article discusses the distinction between substantive and procedural rationality made by Herbert Simon, which has provided the conceptual framework for the empirical research on the boundaries of human rationality. In this research, two approaches with a different understanding of heuristics for cognition and choice are distinguished. In the first approach (David Kahneman, Amos Tversky), heuristics is interpreted as a source of the pathologies in human rationality. In the second (Gerd Gig...

  3. The strategic labor allocation proces : a model of strategic HRM

    NARCIS (Netherlands)

    Bax, Erik H.

    2002-01-01

    In this article the Strategic Labor Allocation Process model (SLAP) is described. The model relates HR-strategies to structure, culture and task technology to HR-policies like recruitment, appraisal and rewarding, to business strategy and to socio-cultural, economic, institutional and technological

  4. learning environments and the learning proces of interaction

    DEFF Research Database (Denmark)

    Jørgensen, Christian Helms

    2004-01-01

    In recent years, learning in working life has been launched as an important approach in relation to the urgent need for competence-development in our modern knowledge society. But what does it mean in practice? What can and what cannot be learned on the job; what is learned better at courses......, and their results, findings and recommendations are summed up in this book. The book ranges from the background for this development, over general mapping of the area from social, learning and political angles, the development of an overview model and analysis of a wide variety of practical approaches...... to the concluding perspectives on a practical, a theoretical and a political level. On the practical level, the door is opened for close interaction between workplaces and educational organisers, and politically for broad cooperation between the state, the partners in the labour market, and educational institutions...

  5. CDM Werkvormen : Creatieve werkvormen voor het Collaborative Decision Making proces

    NARCIS (Netherlands)

    Bemmel, I.E. van; Eikelboom, A.R.; Thönissen, F.H.

    2012-01-01

    Eén van de grootste uitdagingen bij complexe vraagstukken is het creëren van unity of effort bij de verschillende partijen die aan complexe samenwerkingsverbanden deelnemen. Maar, hoe gaan alle neuzen dezelfde kant op staan? Hoe geven de partijen handen en voeten aan doelstellingen? En hoe gaan zij

  6. Iranian mental health survey: design and field proced.

    Directory of Open Access Journals (Sweden)

    Afarin Rahimi-Movaghar

    2014-06-01

    Full Text Available Iranian Mental Health Survey (IranMHS was conducted to assess the twelve-month prevalence and severity of psychiatric disorders in the Iranian adult population and to determine the pattern of health care utilization and cost of services. IranMHS is a cross-sectional national household survey with face-to-face interviews as the main data collection method. The study was carried out between January and June 2011. A three-stage probability sampling was applied for the selection of a representative sample from the non-institutionalized population aged 15 to 64. The primary instrument utilized for assessing the prevalence of mental disorders was the Persian version of Composite International Diagnosis Interview, version 2.1. The instruments for assessing the service and cost of mental illness were developed by the research team. The response rate was 86.2%, and a total of 7886 individuals participated in the study. Sampling weights were the joint product of inverse probability of unit selection, non-response weights and post-stratification weights. This paper presents an overview of the study design, fieldwork organization and procedures, weightings and analysis. The strengths and limitations of the study are also discussed.

  7. Prenatale screening infectieziekten en erytrocytenimmunisatie (PSIE) : proces monitor 2013

    NARCIS (Netherlands)

    Ploeg, C.P.B. van der; Schönbeck, Y.; Hirschberg, H.

    2015-01-01

    Belangrijkste resultaten Prenatale Screening en erytrocytenimmunisatie over 2013. De Prenatale Screening Infectieziekten en Erytocytenimmuni-satie (PSIE) is een landelijk bevolkingsonderzoek waarbij een zwangere vrouw in het eerste verloskundige consult een bloedonderzoek aangeboden krijgt. Het

  8. Estudo da procedência dos pacientes e dos tipos de tireoidopatias encontradas no Ambulatório de Endocrinologia do HSL-PUCRS nos anos de 2005 e 2006 = Study of the origin of patients and types of thyroidopathies observed in the Endocrinology Outpatient Department of Hospital São Lucas – PUCRS from 2005-2006

    Directory of Open Access Journals (Sweden)

    Grazia, Yara Roesch

    2006-01-01

    Full Text Available Objetivos: Identificar a procedência e as características clínicas dos pacientes em acompanhamento no ambulatório de tireoidopatias do HSL-PUCRS entre 2005-2006. Métodos: Realizado estudo retrospectivo, sendo que do total de 824 consultas agendadas no período de 1º de julho de 2005 a 31 de julho de 2006 foram revisados aleatoriamente os prontuários de 432 pacientes. Destes, 185 apresentaram as patologias em estudo, sendo seus dados protocolados. Os resultados foram analisados através de estatística descritiva, teste do qui-quadrado e exato de Fisher. Resultados: A distribuição das doenças em estudo segundo ordem de freqüência foram: tireoidite de Hashimoto (51,9% dos casos, doença de Graves (35,1%, bócio multinodular tóxico (9,7% e adenoma tóxico (3,2%. Foram procedentes de Porto Alegre 37,3% dos pacientes e 61,1% eram de outros locais. Houve diferença estatisticamente significativa (p < 0,05 quanto à presença de auto-anticorpos entre as doenças mediadas pela auto-imunidade e aquelas em que não há envolvimento da mesma. Os pacientes com tireoidite de Hashimoto realizaram reposição de hormônios em 94,8% dos casos e os portadores de doença de Graves realizaram terapia medicamentosa anteriormente ao iodo-radioativo em 37 casos (56,9%. Conclusões: Os pacientes eram procedentes, em sua grande maioria, de locais próximos à região metropolitana. Acredita-se que seja menos oneroso o deslocamento do paciente a centros de atendimento de nível terciário do que a implementação de um serviço altamente especializado nessas regiões

  9. Caracterização e avaliação de três grupos de arroz-de-sequeiro de diferentes procedências por meio da sensitividade à radiação gama Characterization and evaluation of three groups of rice upland of different origins through gamma-ray sensitivity

    Directory of Open Access Journals (Sweden)

    Luís Roberto Franco Rodrigues

    2002-04-01

    Full Text Available A caracterização e avaliação de variedades de arroz auxiliam na seleção dos parentais e na ampliação da base genética dos programas de melhoramento. Este trabalho teve como objetivo caracterizar e avaliar três grupos de arroz-de-sequeiro (Oryza sativa L. de diferentes procedências por meio da sensitividade à radiação gama. Sementes de 84 variedades procedentes do Japão, Filipinas e Brasil foram submetidas a v��rias dosagens de radiação gama e semeadas em caixas de madeira no delineamento em blocos completos ao acaso com três repetições. O experimento foi instalado em casa de vegetação, em 1991, no Centro de Energia Nuclear na Agricultura (CENA, da Universidade de São Paulo (USP. Mediu-se a sensitividade por meio dos efeitos fisiológicos produzidos na geração M1; determinaram-se as porcentagens de emergência, a sobrevivência e a altura das plântulas. Os resultados mostraram diferenças significativas de sensitividade à radiação gama entre grupos em todos os caracteres avaliados.The characterization and evaluation of varieties of rice aid in the parents selection and in the increase of the genetic base of breeding programs. The present work was carried out to characterize and to evaluate three groups of rice upland (Oryza sativa L. of different origins through gamma-ray sensitivity. Seeds of 84 varieties collected from Japan, Philippines and Brazil, were submitted to various doses of gamma-radiation and sown in wooden boxes. The experiment was conducted in 1991 at greenhouse according to randomized complete block design with three replications. Physiological effects caused by radiation in the M1 generation, such as seed emergency, seedling height and survival rate, were determined and evaluated. The results showed significant differences of sensitivity to the radiation among three groups for all traits evaluated.

  10. Rumble surfaces

    CSIR Research Space (South Africa)

    National Institute for Transport and Road

    1977-01-01

    Full Text Available Rumble surfaces are intermittent short lengths of coarse-textured road surfacings on which vehicle tyres produce a rumbling sound. used in conjunction with appropriate roadsigns and markings, they can reduce accidents on rural roads by alerting...

  11. Surface thermodynamics

    International Nuclear Information System (INIS)

    Garcia-Moliner, F.

    1975-01-01

    Basic thermodynamics of a system consisting of two bulk phases with an interface. Solid surfaces: general. Discussion of experimental data on surface tension and related concepts. Adsorption thermodynamics in the Gibbsian scheme. Adsorption on inert solid adsorbents. Systems with electrical charges: chemistry and thermodynamics of imperfect crystals. Thermodynamics of charged surfaces. Simple models of charge transfer chemisorption. Adsorption heat and related concepts. Surface phase transitions

  12. Surface mining

    Science.gov (United States)

    Robert Leopold; Bruce Rowland; Reed Stalder

    1979-01-01

    The surface mining process consists of four phases: (1) exploration; (2) development; (3) production; and (4) reclamation. A variety of surface mining methods has been developed, including strip mining, auger, area strip, open pit, dredging, and hydraulic. Sound planning and design techniques are essential to implement alternatives to meet the myriad of laws,...

  13. Superhydrophobic surfaces

    Science.gov (United States)

    Wang, Evelyn N; McCarthy, Matthew; Enright, Ryan; Culver, James N; Gerasopoulos, Konstantinos; Ghodssi, Reza

    2015-03-24

    Surfaces having a hierarchical structure--having features of both microscale and nanoscale dimensions--can exhibit superhydrophobic properties and advantageous condensation and heat transfer properties. The hierarchical surfaces can be fabricated using biological nanostructures, such as viruses as a self-assembled nanoscale template.

  14. Surface characterization

    Science.gov (United States)

    Mandla A. Tshabalala

    2005-01-01

    Surface properties of wood play an important role when wood is used or processed into different commodities such as siding, joinery, textiles, paper, sorption media or wood composites. Thus, for example, the quality and durability of a wood coating are determined by the surface properties of the wood and the coating. The same is true for wood composites, as the...

  15. Ética de la asistencia primaria a los niños de procedencia internacional Ética da assistência primária às crianças de procedência internacional Ethics of primary health care for children of international origin

    Directory of Open Access Journals (Sweden)

    Vicente Bellver Capella

    Full Text Available La inmigración se ha convertido en un fenómeno universal. Uno de sus efectos es el incremento de los niños de procedencia internacional en las consultas de pediatría. Se trata de una población doblemente vulnerable, por tratarse de niños y por proceder de contextos culturales extraños a los del país de acogida. Ante esta realidad emergente es imprescindible preguntarse por el tipo de asistencia sanitaria que deben recibir. En el presente artículo se proponen principios éticos de actuación inspirados en las principales normas internacionales sobre bioética y derechos de los niños: principio de vulnerabilidad; principio de respeto y amor, y principio de acceso y atención sanitaria. Finalmente, se proponen algunas políticas que las administraciones podrían (deberían implementar para garantizar una asistencia pediátrica correcta a los niños inmigrantes.A imigração se converteu num fenômeno universal. Um de seus efeitos é o incremento das crianças de procedência internacional nas consultas de pediatria. Trata-se de uma população duplamente vulnerável por se tratar de crianças e por proceder de contextos culturais estranhos aos do país de acolhida. Ante esta realidade emergente é imprescindível perguntar-se pelo tipo de assistência sanitária que devem receber. No presente artigo se propõem princípios éticos de atuação inspirados nas principais normas internacionais sobre bioética e direitos das crianças: princípio de vulnerabilidade; princípio de respeito e amor, e princípio de acesso e atenção sanitária. Finalmente, se propõem algumas políticas que as administrações poderiam (deveriam implementar para garantir uma assistência pediátrica correta às crianças imigrantes.Immigration has become an universal phenomenon. One of its effects is the increase in children of international origin in pediatric consultation. This is a doubly vulnerable population, because of being children and because of

  16. Convex surfaces

    CERN Document Server

    Busemann, Herbert

    2008-01-01

    This exploration of convex surfaces focuses on extrinsic geometry and applications of the Brunn-Minkowski theory. It also examines intrinsic geometry and the realization of intrinsic metrics. 1958 edition.

  17. Surface boxplots

    KAUST Repository

    Genton, Marc G.

    2014-01-22

    In this paper, we introduce a surface boxplot as a tool for visualization and exploratory analysis of samples of images. First, we use the notion of volume depth to order the images viewed as surfaces. In particular, we define the median image. We use an exact and fast algorithm for the ranking of the images. This allows us to detect potential outlying images that often contain interesting features not present in most of the images. Second, we build a graphical tool to visualize the surface boxplot and its various characteristics. A graph and histogram of the volume depth values allow us to identify images of interest. The code is available in the supporting information of this paper. We apply our surface boxplot to a sample of brain images and to a sample of climate model outputs.

  18. Surface boxplots

    KAUST Repository

    Genton, Marc G.; Johnson, Christopher; Potter, Kristin; Stenchikov, Georgiy L.; Sun, Ying

    2014-01-01

    In this paper, we introduce a surface boxplot as a tool for visualization and exploratory analysis of samples of images. First, we use the notion of volume depth to order the images viewed as surfaces. In particular, we define the median image. We use an exact and fast algorithm for the ranking of the images. This allows us to detect potential outlying images that often contain interesting features not present in most of the images. Second, we build a graphical tool to visualize the surface boxplot and its various characteristics. A graph and histogram of the volume depth values allow us to identify images of interest. The code is available in the supporting information of this paper. We apply our surface boxplot to a sample of brain images and to a sample of climate model outputs.

  19. Surface channeling

    International Nuclear Information System (INIS)

    Sizmann, R.; Varelas, C.

    1976-01-01

    There is experimental evidence that swift light ions incident at small angles towards single crystalline surfaces can lose an appreciable fraction of their kinetic energy during reflection. It is shown that these projectiles penetrate into the bulk surface region of the crystal. They can travel as channeled particles along long paths through the solid (surface channeling). The angular distribution and the depth history of the re-emerged projectiles are investigated by computer simulations. A considerable fraction of the penetrating projectiles re-emerges from the crystal with constant transverse energy if the angle of incidence is smaller than the critical angle for axial channeling. Analytical formulae are derived based on a diffusion model for surface channeling. A comparison with experimental data exhibits the relevance of the analytical solutions. (Auth.)

  20. Martian surface

    International Nuclear Information System (INIS)

    Carr, M.H.

    1987-01-01

    The surface of Mars is characterized on the basis of reformatted Viking remote-sensing data, summarizing results published during the period 1983-1986. Topics examined include impact craters, ridges and faults, volcanic studies (modeling of surface effects on volcanic activity, description and interpretation of volcanic features, and calculations on lava-ice interactions), the role of liquid water on Mars, evidence for abundant ground ice at high latitudes, water-cycle modeling, and the composition and dynamics of Martian dust

  1. Surface decontamination

    International Nuclear Information System (INIS)

    Silva, S. da; Teixeira, M.V.

    1986-06-01

    The general methods of surface decontamination used in laboratory and others nuclear installations areas, as well as the procedures for handling radioactive materials and surfaces of work are presented. Some methods for decontamination of body external parts are mentioned. The medical supervision and assistance are required for internal or external contamination involving or not lesion in persons. From this medical radiation protection decontamination procedures are determined. (M.C.K.) [pt

  2. Surface phonons

    CERN Document Server

    Wette, Frederik

    1991-01-01

    In recent years substantial progress has been made in the detection of surface phonons owing to considerable improvements in inelastic rare gas scattering tech­ niques and electron energy loss spectroscopy. With these methods it has become possible to measure surface vibrations in a wide energy range for all wave vectors in the two-dimensional Brillouin zone and thus to deduce the complete surface phonon dispersion curves. Inelastic atomic beam scattering and electron energy loss spectroscopy have started to play a role in the study of surface phonons similar to the one played by inelastic neutron scattering in the investigation of bulk phonons in the last thirty years. Detailed comparison between experimen­ tal results and theoretical studies of inelastic surface scattering and of surface phonons has now become feasible. It is therefore possible to test and to improve the details of interaction models which have been worked out theoretically in the last few decades. At this point we felt that a concise, co...

  3. Mostly surfaces

    CERN Document Server

    Schwartz, Richard Evan

    2011-01-01

    This book presents a number of topics related to surfaces, such as Euclidean, spherical and hyperbolic geometry, the fundamental group, universal covering surfaces, Riemannian manifolds, the Gauss-Bonnet Theorem, and the Riemann mapping theorem. The main idea is to get to some interesting mathematics without too much formality. The book also includes some material only tangentially related to surfaces, such as the Cauchy Rigidity Theorem, the Dehn Dissection Theorem, and the Banach-Tarski Theorem. The goal of the book is to present a tapestry of ideas from various areas of mathematics in a clear and rigorous yet informal and friendly way. Prerequisites include undergraduate courses in real analysis and in linear algebra, and some knowledge of complex analysis.

  4. Surface rights

    Directory of Open Access Journals (Sweden)

    Regina Célia Corrêa Landim

    2009-06-01

    Full Text Available In many cities of Brazil, social inequality is illustrated by violence, poverty, and unemployment located next to luxurious residential towers and armored passenger cars. In the face of this situation, the National Movement of Urban Reform encouraged the inclusion of the social function of property in Brazil's new constitution of 1988. Surface rights represent an urbanistic instrument in the city statute that is best aligned to the constitutional principles and urban policies. The current article compares two laws that govern the principle of surface rights and provides a brief history of the evolution of the state based on illuminism and the consequent change in paradigm affecting individual rights, including property and civil rights, and their interpretation under the Constitution. The article concludes by suggesting the use of land surface rights in a joint operation, matching the ownership of the property with urban planning policies and social interest.

  5. Attack surfaces

    DEFF Research Database (Denmark)

    Gruschka, Nils; Jensen, Meiko

    2010-01-01

    The new paradigm of cloud computing poses severe security risks to its adopters. In order to cope with these risks, appropriate taxonomies and classification criteria for attacks on cloud computing are required. In this work-in-progress paper we present one such taxonomy based on the notion...... of attack surfaces of the cloud computing scenario participants....

  6. Surface smoothness

    DEFF Research Database (Denmark)

    Tummala, Sudhakar; Dam, Erik B.

    2010-01-01

    accuracy, such novel markers must therefore be validated against clinically meaningful end-goals such as the ability to allow correct diagnosis. We present a method for automatic cartilage surface smoothness quantification in the knee joint. The quantification is based on a curvature flow method used....... We demonstrate that the fully automatic markers eliminate the time required for radiologist annotations, and in addition provide a diagnostic marker superior to the evaluated semi-manual markers....

  7. Surfaces of Building Practice

    OpenAIRE

    Surynková, Petra

    2009-01-01

    My diploma thesis Surfaces of Building Practice deals with the basic properties of surfaces, their mathematical description, categorization, and application in technical practice. Each studied surface is defined and its process of construction and parametrical description is listed. The thesis studies selected types of surfaces in details - these surfaces include surfaces of revolution, ruled surfaces, screw surfaces, and translational surfaces. An application of each studied surfaces is show...

  8. Surface excitation parameter for rough surfaces

    International Nuclear Information System (INIS)

    Da, Bo; Salma, Khanam; Ji, Hui; Mao, Shifeng; Zhang, Guanghui; Wang, Xiaoping; Ding, Zejun

    2015-01-01

    Graphical abstract: - Highlights: • Instead of providing a general mathematical model of roughness, we directly use a finite element triangle mesh method to build a fully 3D rough surface from the practical sample. • The surface plasmon excitation can be introduced to the realistic sample surface by dielectric response theory and finite element method. • We found that SEP calculated based on ideal plane surface model are still reliable for real sample surface with common roughness. - Abstract: In order to assess quantitatively the importance of surface excitation effect in surface electron spectroscopy measurement, surface excitation parameter (SEP) has been introduced to describe the surface excitation probability as an average number of surface excitations that electrons can undergo when they move through solid surface either in incoming or outgoing directions. Meanwhile, surface roughness is an inevitable issue in experiments particularly when the sample surface is cleaned with ion beam bombardment. Surface roughness alters not only the electron elastic peak intensity but also the surface excitation intensity. However, almost all of the popular theoretical models for determining SEP are based on ideal plane surface approximation. In order to figure out whether this approximation is efficient or not for SEP calculation and the scope of this assumption, we proposed a new way to determine the SEP for a rough surface by a Monte Carlo simulation of electron scattering process near to a realistic rough surface, which is modeled by a finite element analysis method according to AFM image. The elastic peak intensity is calculated for different electron incident and emission angles. Assuming surface excitations obey the Poisson distribution the SEPs corrected for surface roughness are then obtained by analyzing the elastic peak intensity for several materials and for different incident and emission angles. It is found that the surface roughness only plays an

  9. Cryogenic Selective Surfaces

    Data.gov (United States)

    National Aeronautics and Space Administration — Selective surfaces have wavelength dependent emissivity/absorption. These surfaces can be designed to reflect solar radiation, while maximizing infrared emittance,...

  10. Characterization of solid surfaces

    National Research Council Canada - National Science Library

    Kane, Philip F; Larrabee, Graydon B

    1974-01-01

    .... A comprehensive review of surface analysis, this important volume surveys both principles and techniques of surface characterization, describes instrumentation, and suggests the course of future research...

  11. The NuSTAR Extragalactic Survey: First Direct Measurements of the Greater Than Or Similar To 10 Kev X-Ray Luminosity Function For Active Galactic Nuclei At z > 0.1

    DEFF Research Database (Denmark)

    Aird, J.; Alexander, D. M.; Ballantyne, D. R.

    2015-01-01

    We present the first direct measurements of the rest-frame 10-40 keV X-ray luminosity function (XLF) of active galactic nuclei (AGNs) based on a sample of 94 sources at 0.1 ... program. Our results are consistent with the strong evolution of the AGN population seen in prior, lower-energy studies of the XLF. However, different models of the intrinsic distribution of absorption, which are used to correct for selection biases, give significantly different predictions for the total...... component (with a relative normalization of R ∼ 2 at all luminosities) can bring extrapolations of the XLF from 2-10 keV into agreement with our NuSTAR sample. Ultimately, X-ray spectral analysis of the NuSTAR sources is required to break this degeneracy between the distribution of absorbing column...

  12. Open algebraic surfaces

    CERN Document Server

    Miyanishi, Masayoshi

    2000-01-01

    Open algebraic surfaces are a synonym for algebraic surfaces that are not necessarily complete. An open algebraic surface is understood as a Zariski open set of a projective algebraic surface. There is a long history of research on projective algebraic surfaces, and there exists a beautiful Enriques-Kodaira classification of such surfaces. The research accumulated by Ramanujan, Abhyankar, Moh, and Nagata and others has established a classification theory of open algebraic surfaces comparable to the Enriques-Kodaira theory. This research provides powerful methods to study the geometry and topology of open algebraic surfaces. The theory of open algebraic surfaces is applicable not only to algebraic geometry, but also to other fields, such as commutative algebra, invariant theory, and singularities. This book contains a comprehensive account of the theory of open algebraic surfaces, as well as several applications, in particular to the study of affine surfaces. Prerequisite to understanding the text is a basic b...

  13. Surfaces with Natural Ridges

    DEFF Research Database (Denmark)

    Brander, David; Markvorsen, Steen

    2015-01-01

    We discuss surfaces with singularities, both in mathematics and in the real world. For many types of mathematical surface, singularities are natural and can be regarded as part of the surface. The most emblematic example is that of surfaces of constant negative Gauss curvature, all of which...

  14. Approximation by Cylinder Surfaces

    DEFF Research Database (Denmark)

    Randrup, Thomas

    1997-01-01

    We present a new method for approximation of a given surface by a cylinder surface. It is a constructive geometric method, leading to a monorail representation of the cylinder surface. By use of a weighted Gaussian image of the given surface, we determine a projection plane. In the orthogonal...

  15. Ruled Laguerre minimal surfaces

    KAUST Repository

    Skopenkov, Mikhail; Pottmann, Helmut; Grohs, Philipp

    2011-01-01

    A Laguerre minimal surface is an immersed surface in ℝ 3 being an extremal of the functional ∫ (H 2/K-1)dA. In the present paper, we prove that the only ruled Laguerre minimal surfaces are up to isometry the surfaces ℝ (φλ) = (Aφ, Bφ, Cφ + D cos 2φ

  16. Surface Topography Hinders Bacterial Surface Motility.

    Science.gov (United States)

    Chang, Yow-Ren; Weeks, Eric R; Ducker, William A

    2018-03-21

    We demonstrate that the surface motility of the bacterium, Pseudomonas aeruginosa, is hindered by a crystalline hemispherical topography with wavelength in the range of 2-8 μm. The motility was determined by the analysis of time-lapse microscopy images of cells in a flowing growth medium maintained at 37 °C. The net displacement of bacteria over 5 min is much lower on surfaces containing 2-8 μm hemispheres than on flat topography, but displacement on the 1 μm hemispheres is not lower. That is, there is a threshold between 1 and 2 μm for response to the topography. Cells on the 4 μm hemispheres were more likely to travel parallel to the local crystal axis than in other directions. Cells on the 8 μm topography were less likely to travel across the crowns of the hemispheres and were also more likely to make 30°-50° turns than on flat surfaces. These results show that surface topography can act as a significant barrier to surface motility and may therefore hinder surface exploration by bacteria. Because surface exploration can be a part of the process whereby bacteria form colonies and seek nutrients, these results help to elucidate the mechanism by which surface topography hinders biofilm formation.

  17. SURFACE PHOTOMETRY OF LOW SURFACE BRIGHTNESS GALAXIES

    NARCIS (Netherlands)

    DEBLOK, WJG; VANDERHULST, JM; BOTHUN, GD

    1995-01-01

    Low surface brightness (LSB) galaxies are galaxies dominated by an exponential disc whose central surface brightness is much fainter than the value of mu(B)(0) = 21.65 +/- 0.30 mag arcsec(-2) found by Freeman. In this paper we present broadband photometry of a sample of 21 late-type LSB galaxies.

  18. Surface phonons and elastic surface waves

    Science.gov (United States)

    Büscher, H.; Klein-Heßling, W.; Ludwig, W.

    Theoretical investigations on the dynamics of the (001), (110) and (111) surfaces of some cubic metals (Ag, Cu, Ni) will be reviewed. Both, lattice dynamical and continuum theoretical results are obtained via a Green's function formalism. The main attitude of this paper is the comparison of our results with experiments and with results obtained via slab-calculations. The calculation of elastic surface waves has been performed using a modified surface-green-function-matching method. We have used two different approaches of calculation the bulk Green's function (a) using the spectral representation and (b) a method, what works on residues. The investigations are carried out using shortrange phenomenological potentials. The atomic force constants in the first surface layers are modified to describe surface phonon anomalies, observed by experiments. In the case of Ag (100) and Ag(110) we conclude that the detection of odd symmetry shear modes by Erskine et al. [1 a, b] was not very accurate.

  19. Surface phonons and elastic surface waves

    International Nuclear Information System (INIS)

    Buescher, H.; Klein-Hessling, W.; Ludwig, W.

    1993-01-01

    Theoretical investigations on the dynamics of the (001), (110) and (111) surfaces of some cubic metals (Ag, Cu, Ni) will be reviewed. Both, lattice dynamical and continuum theoretical results are obtained via a Green's function formalism. The main attitude of this paper is the comparison of our results with experiments and with results obtained via slab-calculations. The calculation of elastic surface waves has been performed using a modified surface-green-function-matching method. We have used two different approaches of calculation the bulk Green's function (a) using the spectral representation and (b) a method, what works on residues. The investigations are carried out using shortrange phenomenological potentials. The atomic force constants in the first surface layers are modified to describe surface phonon anomalies, observed by experiments. In the case of Ag(100) and Ag(110) we conclude that the detection of odd symmetry shear modes by Erskine et al. was not very accurate. (orig.)

  20. Computer aided surface representation

    Energy Technology Data Exchange (ETDEWEB)

    Barnhill, R E

    1987-11-01

    The aims of this research are the creation of new surface forms and the determination of geometric and physical properties of surfaces. The full sweep from constructive mathematics through the implementation of algorithms and the interactive computer graphics display of surfaces is utilized. Both three-dimensional and multi- dimensional surfaces are considered. Particular emphasis is given to the scientific computing solution of Department of Energy problems. The methods that we have developed and that we are proposing to develop allow applications such as: Producing smooth contour maps from measured data, such as weather maps. Modeling the heat distribution inside a furnace from sample measurements. Terrain modeling based on satellite pictures. The investigation of new surface forms includes the topics of triangular interpolants, multivariate interpolation, surfaces defined on surfaces and monotone and/or convex surfaces. The geometric and physical properties considered include contours, the intersection of surfaces, curvatures as a interrogation tool, and numerical integration.

  1. Mechanics of active surfaces

    Science.gov (United States)

    Salbreux, Guillaume; Jülicher, Frank

    2017-09-01

    We derive a fully covariant theory of the mechanics of active surfaces. This theory provides a framework for the study of active biological or chemical processes at surfaces, such as the cell cortex, the mechanics of epithelial tissues, or reconstituted active systems on surfaces. We introduce forces and torques acting on a surface, and derive the associated force balance conditions. We show that surfaces with in-plane rotational symmetry can have broken up-down, chiral, or planar-chiral symmetry. We discuss the rate of entropy production in the surface and write linear constitutive relations that satisfy the Onsager relations. We show that the bending modulus, the spontaneous curvature, and the surface tension of a passive surface are renormalized by active terms. Finally, we identify active terms which are not found in a passive theory and discuss examples of shape instabilities that are related to active processes in the surface.

  2. Regularity of Minimal Surfaces

    CERN Document Server

    Dierkes, Ulrich; Tromba, Anthony J; Kuster, Albrecht

    2010-01-01

    "Regularity of Minimal Surfaces" begins with a survey of minimal surfaces with free boundaries. Following this, the basic results concerning the boundary behaviour of minimal surfaces and H-surfaces with fixed or free boundaries are studied. In particular, the asymptotic expansions at interior and boundary branch points are derived, leading to general Gauss-Bonnet formulas. Furthermore, gradient estimates and asymptotic expansions for minimal surfaces with only piecewise smooth boundaries are obtained. One of the main features of free boundary value problems for minimal surfaces is t

  3. Advanced Surface Technology

    DEFF Research Database (Denmark)

    Møller, Per; Nielsen, Lars Pleht

    of the components. It covers everything from biocompatible surfaces of IR absorbent or reflective surfaces to surfaces with specific properties within low friction, hardness, corrosion, colors, etc. The book includes more than 400 pages detailing virtually all analysis methods for examining at surfaces.......This new significant book on advanced modern surface technology in all its variations, is aimed at both teaching at engineering schools and practical application in industry. The work covers all the significant aspects of modern surface technology and also describes how new advanced techniques make...

  4. Extremal surface barriers

    International Nuclear Information System (INIS)

    Engelhardt, Netta; Wall, Aron C.

    2014-01-01

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy

  5. PREFACE: Vibrations at surfaces Vibrations at surfaces

    Science.gov (United States)

    Rahman, Talat S.

    2011-12-01

    This special issue is dedicated to the phenomenon of vibrations at surfaces—a topic that was indispensible a couple of decades ago, since it was one of the few phenomena capable of revealing the nature of binding at solid surfaces. For clean surfaces, the frequencies of modes with characteristic displacement patterns revealed how surface geometry, as well as the nature of binding between atoms in the surface layers, could be different from that in the bulk solid. Dispersion of the surface phonons provided further measures of interatomic interactions. For chemisorbed molecules on surfaces, frequencies and dispersion of the vibrational modes were also critical for determining adsorption sites. In other words, vibrations at surfaces served as a reliable means of extracting information about surface structure, chemisorption and overlayer formation. Experimental techniques, such as electron energy loss spectroscopy and helium-atom-surface scattering, coupled with infra-red spectroscopy, were continually refined and their resolutions enhanced to capture subtleties in the dynamics of atoms and molecules at surfaces. Theoretical methods, whether based on empirical and semi-empirical interatomic potential or on ab initio electronic structure calculations, helped decipher experimental observations and provide deeper insights into the nature of the bond between atoms and molecules in regions of reduced symmetry, as encountered on solid surfaces. Vibrations at surfaces were thus an integral part of the set of phenomena that characterized surface science. Dedicated workshops and conferences were held to explore the variety of interesting and puzzling features revealed in experimental and theoretical investigations of surface vibrational modes and their dispersion. One such conference, Vibrations at Surfaces, first organized by Harald Ibach in Juelich in 1980, continues to this day. The 13th International Conference on Vibrations at Surfaces was held at the University of

  6. Induced surface stress at crystal surfaces

    International Nuclear Information System (INIS)

    Dahmen, K.

    2002-05-01

    Changes of the surfaces stress Δτ (s) can be studied by observing the bending of thin crystalline plates. With this cantilever method one can gain the induced change of surface stress Δτ (s) from the bending of plates with the help of elasticity theory. For elastic isotropic substrates the relevant relations are known. Here the relations are generalized to elastic anisotropic crystals with a C 2v - Symmetry. The equilibrium shapes of crystalline plates oriented along the (100)-, (110)-, or (111)-direction which are clamped along one edge are calculated with a numeric method under the load of a homogeneous but pure isotropic or anisotropic surface stress. The results can be displayed with the dimensionality, so that the effect of clamping can be described in a systematic way. With these tabulated values one can evaluate cantilever experiments exactly. These results are generalized to cantilever methods for determining magnetoelastic constants. It is shown which magnetoelastic constants are measured in domains of thin films with ordered structures. The eigenshape and the eigenfrequency of plates constraint through a clamping at one side are calculated. These results give a deeper understanding of the elastic anisotropy. The induced surface stress of oxygen on the (110)-surface of molybdenum is measured along the principle directions Δτ [001] and Δτ [ anti 110] . The anisotropy of the surface stress is found for the p(2 x 2)-reconstruction. Lithium induces a tensile surface stress on the Molybdenum (110)-surface up to a coverage of Θ = 0, 3 monolayer. For a higher coverage the induced stress drops and reaches a level of less than -1, 2 N/m at one monolayer. It is shown, that cobalt induces a linear increasing stress with respect to the coverage on the (100)-surface of copper with a value of 2, 4GPa. The copper (100)-surface is bombarded with accelerated ions in the range between 800-2200 eV. The resulting induced compressive stress (Δτ (s) < 0) of the order

  7. Smooth polyhedral surfaces

    KAUST Repository

    Gü nther, Felix; Jiang, Caigui; Pottmann, Helmut

    2017-01-01

    Polyhedral surfaces are fundamental objects in architectural geometry and industrial design. Whereas closeness of a given mesh to a smooth reference surface and its suitability for numerical simulations were already studied extensively, the aim of our work is to find and to discuss suitable assessments of smoothness of polyhedral surfaces that only take the geometry of the polyhedral surface itself into account. Motivated by analogies to classical differential geometry, we propose a theory of smoothness of polyhedral surfaces including suitable notions of normal vectors, tangent planes, asymptotic directions, and parabolic curves that are invariant under projective transformations. It is remarkable that seemingly mild conditions significantly limit the shapes of faces of a smooth polyhedral surface. Besides being of theoretical interest, we believe that smoothness of polyhedral surfaces is of interest in the architectural context, where vertices and edges of polyhedral surfaces are highly visible.

  8. Surface Prognostic Charts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surface Prognostic Charts are historical surface prognostic (forecast) charts created by the United States Weather Bureau. They include fronts, isobars, cloud, and...

  9. Integrated Surface Dataset (Global)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Integrated Surface (ISD) Dataset (ISD) is composed of worldwide surface weather observations from over 35,000 stations, though the best spatial coverage is...

  10. Smooth polyhedral surfaces

    KAUST Repository

    Günther, Felix

    2017-03-15

    Polyhedral surfaces are fundamental objects in architectural geometry and industrial design. Whereas closeness of a given mesh to a smooth reference surface and its suitability for numerical simulations were already studied extensively, the aim of our work is to find and to discuss suitable assessments of smoothness of polyhedral surfaces that only take the geometry of the polyhedral surface itself into account. Motivated by analogies to classical differential geometry, we propose a theory of smoothness of polyhedral surfaces including suitable notions of normal vectors, tangent planes, asymptotic directions, and parabolic curves that are invariant under projective transformations. It is remarkable that seemingly mild conditions significantly limit the shapes of faces of a smooth polyhedral surface. Besides being of theoretical interest, we believe that smoothness of polyhedral surfaces is of interest in the architectural context, where vertices and edges of polyhedral surfaces are highly visible.

  11. Surface freezing of water

    OpenAIRE

    P?rez-D?az, J. L.; ?lvarez-Valenzuela, M. A.; Rodr?guez-Celis, F.

    2016-01-01

    Freezing, melting, evaporation and condensation of water are essential ingredients for climate and eventually life on Earth. In the present work, we show how surface freezing of supercooled water in an open container is conditioned and triggered?exclusively?by humidity in air. Additionally, a change of phase is demonstrated to be triggered on the water surface forming surface ice crystals prior to freezing of bulk. The symmetry of the surface crystal, as well as the freezing point, depend on ...

  12. Biomaterials surface science

    CERN Document Server

    Taubert, Andreas; Rodriguez-Cabello, José Carlos

    2013-01-01

    The book provides an overview of the highly interdisciplinary field of surface science in the context of biological and biomedical applications. The covered topics range from micro- and nanostructuring for imparting functionality in a top-down manner to the bottom-up fabrication of gradient surfaces by self-assembly, from interfaces between biomaterials and living matter to smart, stimuli-responsive surfaces, and from cell and surface mechanics to the elucidation of cell-chip interactions in biomedical devices.

  13. Decontamination of floor surfaces

    International Nuclear Information System (INIS)

    Smirous, F.

    1983-01-01

    Requirements are presented put on the surfaces of floors of radiochemical workplaces. The mechanism is described of retaining the contaminant in the surface of the flooring, ways of reducing the hazards of floor surface contamination, decontamination techniques and used decontamination agents. (J.P.)

  14. Surface vibrational spectroscopy

    International Nuclear Information System (INIS)

    Erskine, J.L.

    1984-01-01

    A brief review of recent studies which combine measurements of surface vibrational energies with lattice dynamical calculations is presented. These results suggest that surface vibrational spectroscopy offers interesting prospects for use as a molecular-level probe of surface geometry, adsorbate bond distances and molecular orientations

  15. Sulfide Mineral Surfaces

    International Nuclear Information System (INIS)

    Rosso, Kevin M.; Vaughan, David J.

    2006-01-01

    The past twenty years or so have seen dramatic development of the experimental and theoretical tools available to study the surfaces of solids at the molecular (?atomic resolution?) scale. On the experimental side, two areas of development well illustrate these advances. The first concerns the high intensity photon sources associated with synchrotron radiation; these have both greatly improved the surface sensitivity and spatial resolution of already established surface spectroscopic and diffraction methods, and enabled the development of new methods for studying surfaces. The second centers on the scanning probe microscopy (SPM) techniques initially developed in the 1980's with the first scanning tunneling microscope (STM) and atomic force microscope (AFM) experiments. The direct 'observation' of individual atoms at surfaces made possible with these methods has truly revolutionized surface science. On the theoretical side, the availability of high performance computers coupled with advances in computational modeling has provided powerful new tools to complement the advances in experiment. Particularly important have been the quantum mechanics based computational approaches such as density functional theory (DFT), which can now be easily used to calculate the equilibrium crystal structures of solids and surfaces from first principles, and to provide insights into their electronic structure. In this chapter, we review current knowledge of sulfide mineral surfaces, beginning with an overview of the principles relevant to the study of the surfaces of all crystalline solids. This includes the thermodynamics of surfaces, the atomic structure of surfaces (surface crystallography and structural stability, adjustments of atoms at the surface through relaxation or reconstruction, surface defects) and the electronic structure of surfaces. We then discuss examples where specific crystal surfaces have been studied, with the main sulfide minerals organized by structure type

  16. Sulfide Mineral Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Rosso, Kevin M.; Vaughan, David J.

    2006-08-01

    The past twenty years or so have seen dramatic development of the experimental and theoretical tools available to study the surfaces of solids at the molecular (?atomic resolution?) scale. On the experimental side, two areas of development well illustrate these advances. The first concerns the high intensity photon sources associated with synchrotron radiation; these have both greatly improved the surface sensitivity and spatial resolution of already established surface spectroscopic and diffraction methods, and enabled the development of new methods for studying surfaces. The second centers on the scanning probe microscopy (SPM) techniques initially developed in the 1980's with the first scanning tunneling microscope (STM) and atomic force microscope (AFM) experiments. The direct 'observation' of individual atoms at surfaces made possible with these methods has truly revolutionized surface science. On the theoretical side, the availability of high performance computers coupled with advances in computational modeling has provided powerful new tools to complement the advances in experiment. Particularly important have been the quantum mechanics based computational approaches such as density functional theory (DFT), which can now be easily used to calculate the equilibrium crystal structures of solids and surfaces from first principles, and to provide insights into their electronic structure. In this chapter, we review current knowledge of sulfide mineral surfaces, beginning with an overview of the principles relevant to the study of the surfaces of all crystalline solids. This includes the thermodynamics of surfaces, the atomic structure of surfaces (surface crystallography and structural stability, adjustments of atoms at the surface through relaxation or reconstruction, surface defects) and the electronic structure of surfaces. We then discuss examples where specific crystal surfaces have been studied, with the main sulfide minerals organized by

  17. Surface for dummies

    CERN Document Server

    Rathbone, Andy

    2014-01-01

    Make Microsoft's Surface work-and play-just the way you want it to Microsoft's Surface tablet has the features and personality you're looking for, with a robust environment for business computing that doesn't skimp on fun. Surface for Dummies, 2nd Edition explains how Windows 8.1 Pro and Windows RT differ, and helps you decide which Surface model is best for you. Step by step, this book walks you through both the hardware and software features of the Surface, including the touch cover and type cover, Windows RT and Windows 8.1 Pro operating systems, and the coveted Office Home & Student 2013 s

  18. Radioactive surface contamination monitors

    International Nuclear Information System (INIS)

    Aoyama, Kei; Minagoshi, Atsushi; Hasegawa, Toru

    1994-01-01

    To reduce radiation exposure and prevent contamination from spreading, each nuclear power plant has established a radiation controlled area. People and articles out of the controlled area are checked for the surface contamination of radioactive materials with surface contamination monitors. Fuji Electric has repeatedly improved these monitors on the basis of user's needs. This paper outlines typical of a surface contamination monitor, a personal surface contamination monitor, an article surface contamination monitor and a laundry monitor, and the whole-body counter of an internal contamination monitor. (author)

  19. Surface freezing of water.

    Science.gov (United States)

    Pérez-Díaz, J L; Álvarez-Valenzuela, M A; Rodríguez-Celis, F

    2016-01-01

    Freezing, melting, evaporation and condensation of water are essential ingredients for climate and eventually life on Earth. In the present work, we show how surface freezing of supercooled water in an open container is conditioned and triggered-exclusively-by humidity in air. Additionally, a change of phase is demonstrated to be triggered on the water surface forming surface ice crystals prior to freezing of bulk. The symmetry of the surface crystal, as well as the freezing point, depend on humidity, presenting at least three different types of surface crystals. Humidity triggers surface freezing as soon as it overpasses a defined value for a given temperature, generating a plurality of nucleation nodes. An evidence of simultaneous nucleation of surface ice crystals is also provided.

  20. On rationally supported surfaces

    DEFF Research Database (Denmark)

    Gravesen, Jens; Juttler, B.; Sir, Z.

    2008-01-01

    We analyze the class of surfaces which are equipped with rational support functions. Any rational support function can be decomposed into a symmetric (even) and an antisymmetric (odd) part. We analyze certain geometric properties of surfaces with odd and even rational support functions....... In particular it is shown that odd rational support functions correspond to those rational surfaces which can be equipped with a linear field of normal vectors, which were discussed by Sampoli et al. (Sampoli, M.L., Peternell, M., Juttler, B., 2006. Rational surfaces with linear normals and their convolutions...... with rational surfaces. Comput. Aided Geom. Design 23, 179-192). As shown recently, this class of surfaces includes non-developable quadratic triangular Bezier surface patches (Lavicka, M., Bastl, B., 2007. Rational hypersurfaces with rational convolutions. Comput. Aided Geom. Design 24, 410426; Peternell, M...

  1. Computer aided surface representation

    Energy Technology Data Exchange (ETDEWEB)

    Barnhill, R.E.

    1990-02-19

    The central research problem of this project is the effective representation, computation, and display of surfaces interpolating to information in three or more dimensions. If the given information is located on another surface, then the problem is to construct a surface defined on a surface''. Sometimes properties of an already defined surface are desired, which is geometry processing''. Visualization of multivariate surfaces is possible by means of contouring higher dimensional surfaces. These problems and more are discussed below. The broad sweep from constructive mathematics through computational algorithms to computer graphics illustrations is utilized in this research. The breadth and depth of this research activity makes this research project unique.

  2. Mirror reactor surface study

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A. L.; Damm, C. C.; Futch, A. H.; Hiskes, J. R.; Meisenheimer, R. G.; Moir, R. W.; Simonen, T. C.; Stallard, B. W.; Taylor, C. E.

    1976-09-01

    A general survey is presented of surface-related phenomena associated with the following mirror reactor elements: plasma first wall, ion sources, neutral beams, director converters, vacuum systems, and plasma diagnostics. A discussion of surface phenomena in possible abnormal reactor operation is included. Several studies which appear to merit immediate attention and which are essential to the development of mirror reactors are abstracted from the list of recommended areas for surface work. The appendix contains a discussion of the fundamentals of particle/surface interactions. The interactions surveyed are backscattering, thermal desorption, sputtering, diffusion, particle ranges in solids, and surface spectroscopic methods. A bibliography lists references in a number of categories pertinent to mirror reactors. Several complete published and unpublished reports on surface aspects of current mirror plasma experiments and reactor developments are also included.

  3. Mirror reactor surface study

    International Nuclear Information System (INIS)

    Hunt, A.L.; Damm, C.C.; Futch, A.H.; Hiskes, J.R.; Meisenheimer, R.G.; Moir, R.W.; Simonen, T.C.; Stallard, B.W.; Taylor, C.E.

    1976-01-01

    A general survey is presented of surface-related phenomena associated with the following mirror reactor elements: plasma first wall, ion sources, neutral beams, director converters, vacuum systems, and plasma diagnostics. A discussion of surface phenomena in possible abnormal reactor operation is included. Several studies which appear to merit immediate attention and which are essential to the development of mirror reactors are abstracted from the list of recommended areas for surface work. The appendix contains a discussion of the fundamentals of particle/surface interactions. The interactions surveyed are backscattering, thermal desorption, sputtering, diffusion, particle ranges in solids, and surface spectroscopic methods. A bibliography lists references in a number of categories pertinent to mirror reactors. Several complete published and unpublished reports on surface aspects of current mirror plasma experiments and reactor developments are also included

  4. Ruled Laguerre minimal surfaces

    KAUST Repository

    Skopenkov, Mikhail

    2011-10-30

    A Laguerre minimal surface is an immersed surface in ℝ 3 being an extremal of the functional ∫ (H 2/K-1)dA. In the present paper, we prove that the only ruled Laguerre minimal surfaces are up to isometry the surfaces ℝ (φλ) = (Aφ, Bφ, Cφ + D cos 2φ) + λ(sin φ, cos φ, 0), where A,B,C,D ε ℝ are fixed. To achieve invariance under Laguerre transformations, we also derive all Laguerre minimal surfaces that are enveloped by a family of cones. The methodology is based on the isotropic model of Laguerre geometry. In this model a Laguerre minimal surface enveloped by a family of cones corresponds to a graph of a biharmonic function carrying a family of isotropic circles. We classify such functions by showing that the top view of the family of circles is a pencil. © 2011 Springer-Verlag.

  5. Water at surfaces with tunable surface chemistries

    Science.gov (United States)

    Sanders, Stephanie E.; Vanselous, Heather; Petersen, Poul B.

    2018-03-01

    Aqueous interfaces are ubiquitous in natural environments, spanning atmospheric, geological, oceanographic, and biological systems, as well as in technical applications, such as fuel cells and membrane filtration. Where liquid water terminates at a surface, an interfacial region is formed, which exhibits distinct properties from the bulk aqueous phase. The unique properties of water are governed by the hydrogen-bonded network. The chemical and physical properties of the surface dictate the boundary conditions of the bulk hydrogen-bonded network and thus the interfacial properties of the water and any molecules in that region. Understanding the properties of interfacial water requires systematically characterizing the structure and dynamics of interfacial water as a function of the surface chemistry. In this review, we focus on the use of experimental surface-specific spectroscopic methods to understand the properties of interfacial water as a function of surface chemistry. Investigations of the air-water interface, as well as efforts in tuning the properties of the air-water interface by adding solutes or surfactants, are briefly discussed. Buried aqueous interfaces can be accessed with careful selection of spectroscopic technique and sample configuration, further expanding the range of chemical environments that can be probed, including solid inorganic materials, polymers, and water immiscible liquids. Solid substrates can be finely tuned by functionalization with self-assembled monolayers, polymers, or biomolecules. These variables provide a platform for systematically tuning the chemical nature of the interface and examining the resulting water structure. Finally, time-resolved methods to probe the dynamics of interfacial water are briefly summarized before discussing the current status and future directions in studying the structure and dynamics of interfacial water.

  6. Make your Boy surface

    OpenAIRE

    Ogasa, Eiji

    2013-01-01

    This is an introductory article on the Boy surface. Boy found that RP2 can be immersed into R3 and published it 1901. (The image of) the immersion is called the Boy surface after Boy's discovery. We have created a way to construct the Boy surface by using a pair of scissors, a piece of paper, and a strip of scotch tape. In this article we introduce the way.

  7. Encyclopedia of analytical surfaces

    CERN Document Server

    Krivoshapko, S N

    2015-01-01

    This encyclopedia presents an all-embracing collection of analytical surface classes. It provides concise definitions  and description for more than 500 surfaces and categorizes them in 38 classes of analytical surfaces. All classes are cross references to the original literature in an excellent bibliography. The encyclopedia is of particular interest to structural and civil engineers and serves as valuable reference for mathematicians.

  8. Hot Surface Ignition

    OpenAIRE

    Tursyn, Yerbatyr; Goyal, Vikrant; Benhidjeb-Carayon, Alicia; Simmons, Richard; Meyer, Scott; Gore, Jay P.

    2015-01-01

    Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas tu...

  9. Surface science and catalysis

    International Nuclear Information System (INIS)

    Somorjai, G.A.

    1985-02-01

    Modern surface science studies have explored a large number of metal catalyst systems. Three classes of catalytic reactions can be identified: (1) those that occur over the metal surface; (2) reactions that take place on top of a strongly adsorbed overlayer and (3) reactions that occur on co-adsorbate modified surfaces. Case histories for each class are presented. 44 refs., 13 figs., 3 tabs

  10. Anodized dental implant surface

    Directory of Open Access Journals (Sweden)

    Sunil Kumar Mishra

    2017-01-01

    Full Text Available Purpose: Anodized implants with moderately rough surface were introduced around 2000. Whether these implants enhanced biologic effect to improve the environment for better osseointegration was unclear. The purpose of this article was to review the literature available on anodized surface in terms of their clinical success rate and bone response in patients till now. Materials and Methods: A broad electronic search of MEDLINE and PubMed databases was performed. A focus was made on peer-reviewed dental journals. Only articles related to anodized implants were included. Both animal and human studies were included. Results: The initial search of articles resulted in 581 articles on anodized implants. The initial screening of titles and abstracts resulted in 112 full-text papers; 40 animal studies, 16 studies on cell adhesion and bacterial adhesion onto anodized surfaced implants, and 47 human studies were included. Nine studies, which do not fulfill the inclusion criteria, were excluded. Conclusions: The long-term studies on anodized surface implants do favor the surface, but in most of the studies, anodized surface is compared with that of machined surface, but not with other surfaces commercially available. Anodized surface in terms of clinical success rate in cases of compromised bone and immediately extracted sockets has shown favorable success.

  11. Surface science an introduction

    CERN Document Server

    Hudson, John

    1991-01-01

    The whole field of surface science is covered in this work. Starting with a description of the structure and thermodynamics of clean surfaces, the book goes on to discuss kinetic theory of gases and molecular beam formation. This is followed by a largesection on gas-surface interactions, and another major section on energetic particle-surface interactions. The final chapter provides the background to crystal nucleation and growth. The approach adopted is interdisciplinary and slanted towards theexperimental side, with practical analytical techniques being used to illustrate general princi

  12. Surface chemistry essentials

    CERN Document Server

    Birdi, K S

    2013-01-01

    Surface chemistry plays an important role in everyday life, as the basis for many phenomena as well as technological applications. Common examples range from soap bubbles, foam, and raindrops to cosmetics, paint, adhesives, and pharmaceuticals. Additional areas that rely on surface chemistry include modern nanotechnology, medical diagnostics, and drug delivery. There is extensive literature on this subject, but most chemistry books only devote one or two chapters to it. Surface Chemistry Essentials fills a need for a reference that brings together the fundamental aspects of surface chemistry w

  13. Proces-based modeling of the overflow induced growth of erosional channels

    NARCIS (Netherlands)

    Tuan, T.Q.; Stive, M.J.F.; Verhagen, H.J.; Visser, P.J.

    2008-01-01

    A new process-based approach is introduced for a more efficient computation of the overflow-induced growth of an erosional channel in a noncohesive homogeneous narrow landmass such as the breach growth in a sand-dike. The approach is easy to incorporate in a 1D/2DV morphodynamic model to compute the

  14. The strange trial of Robert Oppenheimer; L'etrange proces de Robert Oppenheimer

    Energy Technology Data Exchange (ETDEWEB)

    Kevles, D.J. [Yale Univ., New Haven, CT (United States); Institut de Technologie de Californie (United States)

    2004-04-01

    Robert Oppenheimer has become the symbol of the scientist tormented and anguished by the consequences of his discoveries. R.Oppenheimer took a major part in the Manhattan project for the designing of the first atomic bomb. During this period he considered the thermonuclear bomb as the next step to reach but after Japan's surrender he reconsidered his position and favoured a more moderate atomic policy. R.Oppenheimer began to militate in favour of an international control of nuclear energy and wanted that Usa relinquish to design the hydrogen bomb. In 1953 in full Mac-Carthysm era, he was accused of being a communist and of spying for Ussr and as a consequence he was deprived of his office in AEC (atomic energy committee) but in 1963 president Lyndon Johnson rehabilitated him and R.Oppenheimer was awarded the highest reward of AEC: the Enrico Fermi prize. (A.C.)

  15. Een kennisintensief proces van waarnemen, beslissen en actie ondernemen. Met nieuwe detectietechnieken minder middelen spuiten

    NARCIS (Netherlands)

    Os, van E.A.; Hemming, J.; Zande, van de J.C.; Snel, J.F.H.

    2007-01-01

    In het verleden werd op een vast moment in de week een cocktail van middelen gespoten om het gewas gezond te houden. Dit veranderde toen duidelijk werd dat chemische middelen ook nadelen hadden. Later kwam daar ook het milieu bij met als gevolg dat de emissie naar de lucht en het oppervlaktewater

  16. Příspěvek k teorii afektivních procesů

    Czech Academy of Sciences Publication Activity Database

    Poláčková Šolcová, Iva; Trnka, R.

    2015-01-01

    Roč. 59, č. 4 (2015), s. 298-314 ISSN 0009-062X R&D Projects: GA ČR(CZ) GP14-02889P Institutional support: RVO:68081740 Keywords : affect * emotion * mood * affective stream * figure Subject RIV: AN - Psychology Impact factor: 0.236, year: 2015

  17. Edukační proces u pacienta s diagnózou diabetes mellitus

    OpenAIRE

    Krmenčíková, Veronika

    2015-01-01

    This Bachelor's thesis covers the topic of Diabetes Mellitus patient education. It consists of a theoretical and a practical part. The theoretical part is further divided into two sections. The first theoretical section describes the condition of Diabetes Mellitus, including possible complications and treatment. The second theoretical part contains a list of basic concepts of patient education and the terms related to the patient education process. The quintessential part of the thesis is the...

  18. Motivatie voor het ouderschap : een onderzoek naar de invloed van attitudes op het proces van gezinsvorming

    NARCIS (Netherlands)

    Niphuis - Nell, M.

    1981-01-01

    The Netherlands National Fertility Survey, conducted in 1969, was the first national fertility survey in the Netherlands. Its findings led to the conclusion that conventional social-demographic variables were no longer of very much significance in accounting for differences in fertility and that it

  19. Proces kształtowania się polityki zagranicznej Indonezji po 1998 roku

    Directory of Open Access Journals (Sweden)

    Damian Gwóźdź

    2015-10-01

    Full Text Available Indonesia has become one of the most internationally “compelling” entities nowadays. Its economic development, large and mobile society, political reforms as well as the impressive combination of Islam and democracy attract world’s attention. Indonesia has every right to be regarded as one of the regional powers, or even the emerging leader in Southeast Asia. The breakthrough came along with the overthrow of president Suharto in 1998. The new authorities started to implement variety of reforms in the entire country that are still in process. The transposition of Indonesia’s role and image in the world created also a need for adopting a new, completely fresh approach towards its foreign policy. This paper focuses on foreign policy of Indonesia since 1998 till current days. It examines its main goals and relations with its neighbors, world’s great powers, as well as the involvement of Indonesia within the international organizations. Indonesia is without a doubt primus inter pares in the Association of Southeast Asia Nations and in the Asia-Pacific Economic Cooperation. Indonesia recognizes its participation within ASEAN as the cornerstone of national foreign policy. Since ASEAN’s establishment in 1967, Indonesia has lead that organization from behind. Nowadays, Indonesia tries to overhaul the whole ASEAN system by pushing for the promotion of democracy and human rights as one of the key agendas for the organization. Within last few years, there was also a deeper Indonesian involvement in G20. Indonesian experience of financial crisis in late 90s and years of economic recession during New Order helps to understand the challenges in today’s world. Sharing that experience within G20, Indonesia initiated different action related to safeguard the international financial institutions and world banking system. The last years brought also a great change in the foreign policy of Indonesia in terms of its relations with the People’s Republic of China and the United States of America. China is no longer regarded as a threat for Indonesia’s elites, but as a prospective economic partner. The diplomatic relations with the United States have been strengthened in recent years as well. Last but not least, the paper focuses on the relations of Indonesia with its closest neighbors. After years of diplomatic discourse and antagonism with the government in Kula Lumpur, Singapore, or Canberra, Indonesia initiates a new phase of cooperation. The years of Konfrontasi are over and Indonesian government opened a new chapter and enjoys the cooperation with Australia, Malaysia, Singapore, and Thailand. Indonesia may be, without a doubt, considered as both regional and middle power, as well as the emerging economic power.

  20. Motivatie voor het ouderschap : een onderzoek naar de invloed van attitudes op het proces van gezinsvorming

    OpenAIRE

    Niphuis - Nell, M.

    1981-01-01

    The Netherlands National Fertility Survey, conducted in 1969, was the first national fertility survey in the Netherlands. Its findings led to the conclusion that conventional social-demographic variables were no longer of very much significance in accounting for differences in fertility and that it was necessary to look for socialpsychological factors to account for differential fertility (Moors, 1974). A literature study was then carried oud with the aim of finding a research instrument whic...

  1. Řízení procesů ve vybraném podniku

    OpenAIRE

    VOTAVOVÁ, Monika

    2016-01-01

    An analysis of processes in a selected company and a proposal for possible improvement in selected processes was the main goal of this diploma thesis. The "order processing" process in chosen company was analysed and optimized within this goal. This process was mapped in detail according to the individual sub-processes inside the monitored process, and an analysis was performed, including measurement, identification of weak points and a proposal for solutions leading to the required optimizat...

  2. Agent-based land markets: Heterogeneous agents, land proces and urban land use change

    NARCIS (Netherlands)

    Filatova, Tatiana; Parker, Dawn C.; van der Veen, A.; Amblard, F.

    2007-01-01

    We construct a spatially explicit agent-based model of a bilateral land market. Heterogeneous agents form their bid and ask prices for land based on the utility that they obtain from a certain location (houte/land) and base on the state of the market (an excess of demand or supply). We underline the

  3. Mod en ny forståelse af den digitaliseringsstrategiske proces

    DEFF Research Database (Denmark)

    Ivang, Reimer

    2007-01-01

    Den digitale teknologi er vigtig, og vigtigheden kan ikke kun afspejles i den konstant stigende mængde af litteratur, der relaterer sig til fænomenet. Men vigtigheden er også identificeret på Danfoss, der er afhandlingens empiriske kontekst. Der synes at være enighed om, at den digitale teknologi...

  4. Cassava Pulp as a Biofuel Feedstock of an Enzymatic Hydrolysis Proces

    Directory of Open Access Journals (Sweden)

    Djuma’ali Djuma’ali

    2013-03-01

    Full Text Available Cassava pulp, a low cost solid byproduct of cassava starch industry, has been proposed as a high potential ethanolic fermentation substrate due to its high residual starch level, low ash content and small particle size of the lignocellulosic fibers. As the economic feasibility depends on complete degradation of the polysaccharides to fermentable glucose, the comparative hydrolytic potential of cassava pulp by six commercial enzymes were studied. Raw cassava pulp (12% w/v, particle size <320 μm hydrolyzed by both commercial pectinolytic (1 and amylolytic (2 enzymes cocktail, yielded 70.06% DE. Hydrothermal treatment of cassava pulp enhanced its susceptibility to enzymatic cleavageas compared to non-hydrothermal treatment raw cassava pulp. Hydrothermal pretreatment has shown that a glucoamylase (3 was the most effective enzyme for hydrolysis process of cassava pulp at temperature 65 °C or 95 °C for 10 min and yielded approximately 86.22% and 90.18% DE, respectively. Enzymatic pretreatment increased cassava pulp vulnerability to cellulase attacks. The optimum conditions for enzymatic pretreatment of 30% (w/v cassava pulp by a potent cellulolytic/ hemicellulolytic enzyme (4 was achieves at 50 °C for 3, meanwhile for liquefaction and saccharification by a thermo-stable α-amylase (5 was achieved at 95 °C for 1 and a glucoamylase (3 at 50 °C for 24 hours, respectively, yielded a reducing sugar level up to 94,1% DE. The high yield of glucose indicates the potential use of enzymatic-hydrothermally treated cassava pulp as a cheap substrate for ethanol production.

  5. Supplier Selection Proces: An Investigation and Implementation Action at Construction/Building Company

    OpenAIRE

    Hensmit, Andre

    2008-01-01

    The investigation was carried out to identify and understand the key characteristic of supplier selection that is to be considered in the real experience by Construction Company in South East Asia, especially Indonesia. The goal of this project focuses on the selection supplier process and its approaches, how the company performing the co-partnership relationship with suppliers, and as well find out the reason fro accomplishing these factors. The project involves interviewing a company in Ind...

  6. Mesenterial pannikulitis er en sjælden inflammatorisk proces i mesenteriets fedtvæv

    DEFF Research Database (Denmark)

    Rolff, Hans Christian; Fallentin, Eva; Wettergren, André

    2011-01-01

    Mesenteric panniculitis (MP) is a rare condition affecting the mesentery of the small bowel and/or colon. Obtaining a diagnosis is dependent on radiological and histological findings. With the increasing use of abdominal CT, more cases of MP will be discovered. We report a case of MP accidentally...... found at CT in a 64 year-old woman who was evaluated for upper abdominal discomfort. Percutaneous ultrasonography guided biopsy secured the diagnosis. There is no consensus on the treatment and management of MP. An approach guided by the patient's symptoms seems suitable....

  7. Proces abstrakce jako faktor v umění a estetický princip

    Directory of Open Access Journals (Sweden)

    Vlastimil Zuska

    2017-03-01

    Full Text Available This essay examines the processes of abstraction in ordinary perception as part of cognitive processes in general and aesthetic experience in particular. Whitehead’s early conceptions of sense perception are drawn on here, and subsequently so are the cognitive operations at the mental pole of events. In addition to affective strata of experience, with reference to Process and Reality and Modes of Thought, the article considers the processes of symbolic reference, conceptual feeling, and conceptual analysis as synthesizing factors in the process of abstraction. The article also analyses the first systematic theory of art, namely, that postulated by Charles Batteux, and his special conception of mimesis. Whitehead’s conception of aesthetic experience as an experience of what he called ‘vivid value’ is then compared with similar ideas held by the Czech structuralists and proponents of reception aesthetics. In his conclusion, with reference to Deleuze and Guattari’s A Thousand Plateaus, the author seeks to demonstrate the role that the act of becoming plays in abstracting aesthetic experience and its contribution to personal and social development. In addition, the author then sets out the distinctions between abstraction in science/logic and abstraction in aesthetic experience/art, which were made by Whitehead and his pupil Susanne Langer.

  8. ANALYZING CERTAIN CHRACTERISTICS OF MUNICIPAL SOLID WASTE GENERATION IN THE PROCES S OF WASTE MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Gábriel Györgyi T #336;ZSÉR

    2010-01-01

    Full Text Available Based on the regulations of Act XLIII/2000 on Waste Management to implement the strategic objectives and targets in the Act for the prevalence of the basic waste management principles a National Waste Management Plan II will be worked out and then accepted by the Parliament as part of the National Environmental Protection Programme. On the basis of the national plan the administrative bodies of environmental protection in accordance with the regional settlement and d evelopment programmes make a regional waste management project with the inclusion of the regional, local authorities, and other authorities concerned as well as the non governmental organisations for environmental protection. In our research we analyze the correlation between municipal solid waste per capita and urbanisation level. We have conducted similar calculations in the filed of population density and income. The study was carried out on a micro region level. Our analysis can help determine the framework conditions and factors that influence waste generation, and therefore should be taken into consideration when designing waste policies .

  9. Reingeneering procesů nákupu ZKL Brno, a. s.

    OpenAIRE

    Šnajdrová, Eva

    2009-01-01

    ZKL Brno, a.s. is manufacturer of rolling and special bearings. The introductory part contains definitions of purchase, reengineering, centralization or stock mnagement. Then a short company description and a description of the original condition of the purchase follows. The main goal of this thesis is to find mistakes in the management of purchase with the help of commodity analysis, personnel analysis and stock analysis. In the end there is a new directive for purchasing presented.

  10. BUSINESS PROCES MANGEMNET SYSTEMS AS A NEW PARADIGM OF IT DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Igor G. Fiodorov

    2015-01-01

    Full Text Available It would be wrong to reduce the paradigm shift in IT development to a change in technology, the emergence of new software or hardware. The development of enterprise information systems based on the BPM is a radical change in our views on methods for business process modeling and for organisation management.

  11. A p An atte proces empt t ss of da oward awada s stan awan b ...

    African Journals Online (AJOL)

    SAM

    2014-08-07

    Aug 7, 2014 ... used as “sorrel meat” or Iyu (Schippers, 2000) and Borno where the .... copper sulphate (CuSO4) and selenium oxide (SeO2) in the ratio. 10:5:1 was ... boric acid containing four drops of bromocresol green/methyl red indicator ...

  12. Náborový proces v mezinárodní společnosti

    OpenAIRE

    Lešková, Tereza

    2017-01-01

    The goal of the thesis Recruitment process in an international company is to analyze processes such as recruitment and selection of employees at Continental Trutnov and to describe the strenghts and weaknesses and to propose actions which could improve the above mentioned HR activities. The theoretical part of the thesis deals generally with personnel management. Furthemore, this part also explains recruitment and selection of employees and it also describes theoretically the process of adapt...

  13. The design of a novel, environmentally improved cotton pre-treatment proces

    NARCIS (Netherlands)

    Bouwhuis, G.H. (Gerrit)

    2011-01-01

    The scope of this thesis of Gerrit Bouwhuis, lecturer at Saxion Research Centre for Design and Technology in Enschede is the development of a new industrial applicable pre-treatment process for cotton based on catalysis. The pre-treatment generally consists of desizing, scouring and bleaching. These

  14. Analýza a zlepšování procesů

    OpenAIRE

    Šimonová, Petra

    2010-01-01

    This thesis describes differences between the functional and process management. Defines the base of theories of the process management. By using various methods of process management in the hypothetical company presents the practical contributions of the process management.

  15. Kúpny rozhodovací proces spotrebiteľa na trhu dekoratívnej kozmetiky

    OpenAIRE

    Kasičová, Nikola

    2015-01-01

    The main goal of this bachelor thesis is to understand the current situation on beauty market in terms of preferences and tendencies of womens buying behavior. By understanding, what are the needs of customers, companies will be able to deliver effective marketing communications and gain competitive advantage. The thesis consists of two parts: theoretical and practical. The theoretical part provides the key information about decision buying process itself and the factors which have crucial im...

  16. Kineziterapijos ir vandens procedūrų efektyvumas gydant nugaros skausmus

    OpenAIRE

    Nasevičiūtė, Danutė

    2005-01-01

    Spinal pain is one of the most frequent reasons of health disorder and consulting a doctor. 60-90% of adults complain of a spinal pain at least once in their lifetime. 50% of adults experience a spinal pain that makes them suspend their work and unbalance their everyday life. This is the main reason of adults’ disability till 45 years old ant the third most frequent reason of adults’ disability over 45 years old. 5-10 % of cases spinal pains are not acute. The aim of this research was to e...

  17. Voorwoord en introductie CDM Werkvormen : Creatieve werkvormen voor het Collaborative Decision Making proces

    NARCIS (Netherlands)

    Bemmel, I.E. van; Eikelboom, A.R.; Thönissen, F.H.

    2012-01-01

    Eén van de grootste uitdagingen bij complexe vraagstukken is het creëren van unity of effort bij de verschillende partijen die aan complexe samenwerkingsverbanden deelnemen. Maar, hoe gaan alle neuzen dezelfde kant op staan? Hoe geven de partijen handen en voeten aan doelstellingen? En hoe gaan zij

  18. Enantiosémie jako výsledek slovotvorných procesů

    Czech Academy of Sciences Publication Activity Database

    Nejedlý, Petr

    2014-01-01

    Roč. 75, č. 3 (2014), s. 181-192 ISSN 0037-7031 R&D Projects: GA ČR GAP406/10/1153 Institutional support: RVO:68378092 Keywords : enantiosemy * etymology * semantics * lexicon * word-formation * lexicology * language development Subject RIV: AI - Linguistics Impact factor: 0.375, year: 2014

  19. Liquid chromatographic determination of polyphenenols in czech beers during brewing proces

    Directory of Open Access Journals (Sweden)

    Chunsriimyatav Ganbaatar

    2015-05-01

    Full Text Available High performance liquid chromatographic (HPLC/UV method was adapted for simultaneous determination of seven polyphenols, including derivatives of benzoic (gallic and vanillic acids and cinnamic acids (p-coumaric, ferulic and sinapic acids, flavan-3-ols (catechin and flavonols (rutin in worts and beers at the various stages of the brewing process. Based on the semi-quantitative HPLC analysis, total polyphenols chromatographic index (TPCI was in the ranges of 5.18 - 19.4 mg/L and 7.37 - 20.7 mg/L for all worts and beers, respectively. The HPLC analyses showed that relatively high levels of (+-catechin and gallic acid were in all the worts and the beers, while the values were much lower for ferulic acid, rutin, vanillic acid, sinapic acid and p-coumaric acid. Polyphenols with relatively high concentrations, that were detected in all tested worts and beers, were gallic acid (1.29 - 4.75 mg/L resp. 2.59 - 4.97 mg/L, (+-catechin (1.66 - 7.95 mg/L resp. 4.70 - 10.0 mg/L and ferulic acid (0.41 - 4.53 mg/L resp. 1.05 - 2.87 mg/L. On the other side, the sinapic acid (0.72 - 1.59 mg/L resp. 0.72 - 2.5 mg/L, rutin (1.17 - 2.03 mg/L resp. 1.16 - 2.85 mg/L, p-coumaric acid (ND - 4.73 mg/L resp. ND - 1.44 mg/L and vanillic acid (ND - 1.52 mg/L resp. 0.75 - 1.81 mg/L were detected in lowest concentrations. In both, worts and beers investigated in this study, the changes in the contents of individual polyphenols were not uniform. In the case of some polyphenols, a decrease in the content was observed after boiling the worts with hops or after the main fermentation until maturation and filtration, but with some polyphenols, the concentrations were constant until the end of the process or even increased.

  20. [Ocular surface system integrity].

    Science.gov (United States)

    Safonova, T N; Pateyuk, L S

    2015-01-01

    The interplay of different structures belonging to either the anterior segment of the eye or its accessory visual apparatus, which all share common embryological, anatomical, functional, and physiological features, is discussed. Explanation of such terms, as ocular surface, lacrimal functional unit, and ocular surface system, is provided.

  1. Pseudospherical surfaces with singularities

    DEFF Research Database (Denmark)

    Brander, David

    2017-01-01

    We study a generalization of constant Gauss curvature −1 surfaces in Euclidean 3-space, based on Lorentzian harmonic maps, that we call pseudospherical frontals. We analyse the singularities of these surfaces, dividing them into those of characteristic and non-characteristic type. We give methods...

  2. Solar absorption surface panel

    Science.gov (United States)

    Santala, Teuvo J.

    1978-01-01

    A composite metal of aluminum and nickel is used to form an economical solar absorption surface for a collector plate wherein an intermetallic compound of the aluminum and nickel provides a surface morphology with high absorptance and relatively low infrared emittance along with good durability.

  3. Random surfaces and strings

    International Nuclear Information System (INIS)

    Ambjoern, J.

    1987-08-01

    The theory of strings is the theory of random surfaces. I review the present attempts to regularize the world sheet of the string by triangulation. The corresponding statistical theory of triangulated random surfaces has a surprising rich structure, but the connection to conventional string theory seems non-trivial. (orig.)

  4. Stiction in surface micromachining

    NARCIS (Netherlands)

    Tas, Niels Roelof; Sonnenberg, A.H.; Jansen, Henricus V.; Legtenberg, R.; Legtenberg, Rob; Elwenspoek, Michael Curt

    1996-01-01

    Due to the smoothness of the surfaces in surface micromachining, large adhesion forces between fabricated structures and the substrate are encountered. Four major adhesion mechanisms have been analysed: capillary forces, hydrogen bridging, electrostatic forces and van der Waals forces. Once contact

  5. Surface Acoustic Wave Devices

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard

    The work of this project is concerned with the simulation of surface acoustic waves (SAW) and topology optimization of SAW devices. SAWs are elastic vibrations that propagate along a material surface and are extensively used in electromechanical filters and resonators in telecommunication. A new...

  6. Bacteria-surface interactions.

    Science.gov (United States)

    Tuson, Hannah H; Weibel, Douglas B

    2013-05-14

    The interaction of bacteria with surfaces has important implications in a range of areas, including bioenergy, biofouling, biofilm formation, and the infection of plants and animals. Many of the interactions of bacteria with surfaces produce changes in the expression of genes that influence cell morphology and behavior, including genes essential for motility and surface attachment. Despite the attention that these phenotypes have garnered, the bacterial systems used for sensing and responding to surfaces are still not well understood. An understanding of these mechanisms will guide the development of new classes of materials that inhibit and promote cell growth, and complement studies of the physiology of bacteria in contact with surfaces. Recent studies from a range of fields in science and engineering are poised to guide future investigations in this area. This review summarizes recent studies on bacteria-surface interactions, discusses mechanisms of surface sensing and consequences of cell attachment, provides an overview of surfaces that have been used in bacterial studies, and highlights unanswered questions in this field.

  7. Protective Surfacing for Playgrounds.

    Science.gov (United States)

    Frost, Joe L.

    Noting that 90 percent of serious playground injuries result from falls to hard surfaces, this paper reviews the advantages and disadvantages of various playground surfacing materials in terms of cost, climate, durability, aesthetics, and play value. Findings are based on the personal experience of the author, government documents, laboratory…

  8. Chapter 8:Surface Characterization

    Science.gov (United States)

    Mandla A. Tshabalala; Joseph Jakes; Mark R. VanLandingham; Shaoxia Wang; Jouko. Peltonen

    2013-01-01

    Surface properties of wood play an important role when wood is used or processed into different commodities such as siding, joinery, textiles, paper, sorption media, or wood composites. Thus, for example, the quality and durability of a wood coating are determined by the surface properties of the wood and the coating. The same is true for wood composites where the...

  9. Response Surface Methodology

    NARCIS (Netherlands)

    Kleijnen, Jack P.C.

    2014-01-01

    Abstract: This chapter first summarizes Response Surface Methodology (RSM), which started with Box and Wilson’s article in 1951 on RSM for real, non-simulated systems. RSM is a stepwise heuristic that uses first-order polynomials to approximate the response surface locally. An estimated polynomial

  10. Surface Loving and Surface Avoiding modes

    OpenAIRE

    Combe, Nicolas; Huntzinger, Jean Roch; Morillo, Joseph

    2008-01-01

    International audience; We theoretically study the propagation of sound waves in GaAs/AlAs superlattices focussing on periodic modes in the vicinity of the band gaps. Based on analytical and numerical calculations, we show that these modes are the product of a quickly oscillating function times a slowly varying envelope function. We carefully study the phase of the envelope function compared to the surface of a semi-infinite superlattice. Especially, the dephasing of the superlattice compared...

  11. Workbench surface editor of brain cortical surface

    Science.gov (United States)

    Dow, Douglas E.; Nowinski, Wieslaw L.; Serra, Luis

    1996-04-01

    We have developed a 3D reach-in tool to manually reconstruct 3D cortical surface patches from 2D brain atlas images. The first application of our cortex editor is building 3D functional maps, specifically Brodmann's areas. This tool may also be useful in clinical practice to adjust incorrectly mapped atlas regions due to the deforming effect of lesions. The cortex editor allows a domain expert to control the correlation of control points across slices. Correct correlation has been difficult for 3D reconstruction algorithms because the atlas slices are far apart and because of the complex topology of the cortex which differs so much from slice to slice. Also, higher precision of the resulting surfaces is demanded since these define 3D brain atlas features upon which future stereotactic surgery may be based. The cortex editor described in this paper provides a tool suitable for a domain expert to use in defining the 3D surface of a Brodmann's area.

  12. Antibacterial Au nanostructured surfaces

    Science.gov (United States)

    Wu, Songmei; Zuber, Flavia; Brugger, Juergen; Maniura-Weber, Katharina; Ren, Qun

    2016-01-01

    We present here a technological platform for engineering Au nanotopographies by templated electrodeposition on antibacterial surfaces. Three different types of nanostructures were fabricated: nanopillars, nanorings and nanonuggets. The nanopillars are the basic structures and are 50 nm in diameter and 100 nm in height. Particular arrangement of the nanopillars in various geometries formed nanorings and nanonuggets. Flat surfaces, rough substrate surfaces, and various nanostructured surfaces were compared for their abilities to attach and kill bacterial cells. Methicillin-resistant Staphylococcus aureus, a Gram-positive bacterial strain responsible for many infections in health care system, was used as the model bacterial strain. It was found that all the Au nanostructures, regardless their shapes, exhibited similar excellent antibacterial properties. A comparison of live cells attached to nanotopographic surfaces showed that the number of live S. aureus cells was flat and rough reference surfaces. Our micro/nanofabrication process is a scalable approach based on cost-efficient self-organization and provides potential for further developing functional surfaces to study the behavior of microbes on nanoscale topographies.We present here a technological platform for engineering Au nanotopographies by templated electrodeposition on antibacterial surfaces. Three different types of nanostructures were fabricated: nanopillars, nanorings and nanonuggets. The nanopillars are the basic structures and are 50 nm in diameter and 100 nm in height. Particular arrangement of the nanopillars in various geometries formed nanorings and nanonuggets. Flat surfaces, rough substrate surfaces, and various nanostructured surfaces were compared for their abilities to attach and kill bacterial cells. Methicillin-resistant Staphylococcus aureus, a Gram-positive bacterial strain responsible for many infections in health care system, was used as the model bacterial strain. It was found that all

  13. Rough Surface Contact

    Directory of Open Access Journals (Sweden)

    T Nguyen

    2017-06-01

    Full Text Available This paper studies the contact of general rough curved surfaces having nearly identical geometries, assuming the contact at each differential area obeys the model proposed by Greenwood and Williamson. In order to account for the most general gross geometry, principles of differential geometry of surface are applied. This method while requires more rigorous mathematical manipulations, the fact that it preserves the original surface geometries thus makes the modeling procedure much more intuitive. For subsequent use, differential geometry of axis-symmetric surface is considered instead of general surface (although this “general case” can be done as well in Chapter 3.1. The final formulas for contact area, load, and frictional torque are derived in Chapter 3.2.

  14. Super Riemann surfaces

    International Nuclear Information System (INIS)

    Rogers, Alice

    1990-01-01

    A super Riemann surface is a particular kind of (1,1)-dimensional complex analytic supermanifold. From the point of view of super-manifold theory, super Riemann surfaces are interesting because they furnish the simplest examples of what have become known as non-split supermanifolds, that is, supermanifolds where the odd and even parts are genuinely intertwined, as opposed to split supermanifolds which are essentially the exterior bundles of a vector bundle over a conventional manifold. However undoubtedly the main motivation for the study of super Riemann surfaces has been their relevance to the Polyakov quantisation of the spinning string. Some of the papers on super Riemann surfaces are reviewed. Although recent work has shown all super Riemann surfaces are algebraic, some areas of difficulty remain. (author)

  15. Defects at oxide surfaces

    CERN Document Server

    Thornton, Geoff

    2015-01-01

    This book presents the basics and characterization of defects at oxide surfaces. It provides a state-of-the-art review of the field, containing information to the various types of surface defects, describes analytical methods to study defects, their chemical activity and the catalytic reactivity of oxides. Numerical simulations of defective structures complete the picture developed. Defects on planar surfaces form the focus of much of the book, although the investigation of powder samples also form an important part. The experimental study of planar surfaces opens the possibility of applying the large armoury of techniques that have been developed over the last half-century to study surfaces in ultra-high vacuum. This enables the acquisition of atomic level data under well-controlled conditions, providing a stringent test of theoretical methods. The latter can then be more reliably applied to systems such as nanoparticles for which accurate methods of characterization of structure and electronic properties ha...

  16. Surface preparation of niobium

    International Nuclear Information System (INIS)

    Kneisel, P.

    1980-01-01

    Any discussion of surface preparation for superconducting rf-surfaces is certainly connected with the question what is the best recipe for achieving high Q-values and high break-down fields. Since the break-down in a cavity is not understood so far and because several mechanisms play a role, it also is not possible to give one recipe which always works. Nevertheless in the past certain preparation techniques for niobium surfaces have been developed and certain rules for preparation can be applied. In the following the to-days state of the art will be described and it is attempted to give a short description of the surface in conjunction with the methods of surface treatments, which generally can be applied to niobium cavities. (orig./WTR)

  17. Surface enhanced Raman scattering

    CERN Document Server

    Furtak, Thomas

    1982-01-01

    In the course of the development of surface science, advances have been identified with the introduction of new diagnostic probes for analytical characterization of the adsorbates and microscopic structure of surfaces and interfaces. Among the most recently de­ veloped techniques, and one around which a storm of controversy has developed, is what has now been earmarked as surface enhanced Raman scattering (SERS). Within this phenomenon, molecules adsorbed onto metal surfaces under certain conditions exhibit an anomalously large interaction cross section for the Raman effect. This makes it possible to observe the detailed vibrational signature of the adsorbate in the ambient phase with an energy resolution much higher than that which is presently available in electron energy loss spectroscopy and when the surface is in contact with a much larger amount of material than that which can be tolerated in infrared absorption experiments. The ability to perform vibrational spectroscopy under these conditions would l...

  18. Land Surface Data Assimilation

    Science.gov (United States)

    Houser, P. R.

    2012-12-01

    Information about land surface water, energy and carbon conditions is of critical importance to real-world applications such as agricultural production, water resource management, flood prediction, water supply, weather and climate forecasting, and environmental preservation. While ground-based observational networks are improving, the only practical way to observe these land surface states on continental to global scales is via satellites. Remote sensing can make spatially comprehensive measurements of various components of the terrestrial system, but it cannot provide information on the entire system (e.g. evaporation), and the observations represent only an instant in time. Land surface process models may be used to predict temporal and spatial terrestrial dynamics, but these predictions are often poor, due to model initialization, parameter and forcing, and physics errors. Therefore, an attractive prospect is to combine the strengths of land surface models and observations (and minimize the weaknesses) to provide a superior terrestrial state estimate. This is the goal of land surface data assimilation. Data Assimilation combines observations into a dynamical model, using the model's equations to provide time continuity and coupling between the estimated fields. Land surface data assimilation aims to utilize both our land surface process knowledge, as embodied in a land surface model, and information that can be gained from observations. Both model predictions and observations are imperfect and we wish to use both synergistically to obtain a more accurate result. Moreover, both contain different kinds of information, that when used together, provide an accuracy level that cannot be obtained individually. Model biases can be mitigated using a complementary calibration and parameterization process. Limited point measurements are often used to calibrate the model(s) and validate the assimilation results. This presentation will provide a brief background on land

  19. PREFACE: Nanostructured surfaces

    Science.gov (United States)

    Palmer, Richard E.

    2003-10-01

    We can define nanostructured surfaces as well-defined surfaces which contain lateral features of size 1-100 nm. This length range lies well below the micron regime but equally above the Ångstrom regime, which corresponds to the interatomic distances on single-crystal surfaces. This special issue of Journal of Physics: Condensed Matter presents a collection of twelve papers which together address the fabrication, characterization, properties and applications of such nanostructured surfaces. Taken together they represent, in effect, a status report on the rapid progress taking place in this burgeoning area. The first four papers in this special issue have been contributed by members of the European Research Training Network ‘NanoCluster’, which is concerned with the deposition, growth and characterization of nanometre-scale clusters on solid surfaces—prototypical examples of nanoscale surface features. The paper by Vandamme is concerned with the fundamentals of the cluster-surface interaction; the papers by Gonzalo and Moisala address, respectively, the optical and catalytic properties of deposited clusters; and the paper by van Tendeloo reports the application of transmission electron microscopy (TEM) to elucidate the surface structure of spherical particles in a catalyst support. The fifth paper, by Mendes, is also the fruit of a European Research Training Network (‘Micro-Nano’) and is jointly contributed by three research groups; it reviews the creation of nanostructured surface architectures from chemically-synthesized nanoparticles. The next five papers in this special issue are all concerned with the characterization of nanostructured surfaces with scanning tunnelling microscopy (STM) and atomic force microscopy (AFM). The papers by Bolotov, Hamilton and Dunstan demonstrate that the STM can be employed for local electrical measurements as well as imaging, as illustrated by the examples of deposited clusters, model semiconductor structures and real

  20. Surface Habitat Systems

    Science.gov (United States)

    Kennedy, Kriss J.

    2009-01-01

    The Surface Habitat Systems (SHS) Focused Investment Group (FIG) is part of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) effort to provide a focused direction and funding to the various projects that are working on human surface habitat designs and technologies for the planetary exploration missions. The overall SHS-FIG effort focuses on directing and guiding those projects that: 1) develop and demonstrate new surface habitat system concepts, innovations, and technologies to support human exploration missions, 2) improve environmental systems that interact with human habitats, 3) handle and emplace human surface habitats, and 4) focus on supporting humans living and working in habitats on planetary surfaces. The activity areas of the SHS FIG described herein are focused on the surface habitat project near-term objectives as described in this document. The SHS-FIG effort focuses on mitigating surface habitat risks (as identified by the Lunar Surface Systems Project Office (LSSPO) Surface Habitat Element Team; and concentrates on developing surface habitat technologies as identified in the FY08 gap analysis. The surface habitat gap assessment will be updated annually as the surface architecture and surface habitat definition continues to mature. These technologies are mapped to the SHS-FIG Strategic Development Roadmap. The Roadmap will bring to light the areas where additional innovative efforts are needed to support the development of habitat concepts and designs and the development of new technologies to support of the LSSPO Habitation Element development plan. Three specific areas of development that address Lunar Architecture Team (LAT)-2 and Constellation Architecture Team (CxAT) Lunar habitat design issues or risks will be focused on by the SHS-FIG. The SHS-FIG will establish four areas of development that will help the projects prepare in their planning for surface habitat systems development. Those development areas are

  1. Antibacterial Au nanostructured surfaces.

    Science.gov (United States)

    Wu, Songmei; Zuber, Flavia; Brugger, Juergen; Maniura-Weber, Katharina; Ren, Qun

    2016-02-07

    We present here a technological platform for engineering Au nanotopographies by templated electrodeposition on antibacterial surfaces. Three different types of nanostructures were fabricated: nanopillars, nanorings and nanonuggets. The nanopillars are the basic structures and are 50 nm in diameter and 100 nm in height. Particular arrangement of the nanopillars in various geometries formed nanorings and nanonuggets. Flat surfaces, rough substrate surfaces, and various nanostructured surfaces were compared for their abilities to attach and kill bacterial cells. Methicillin-resistant Staphylococcus aureus, a Gram-positive bacterial strain responsible for many infections in health care system, was used as the model bacterial strain. It was found that all the Au nanostructures, regardless their shapes, exhibited similar excellent antibacterial properties. A comparison of live cells attached to nanotopographic surfaces showed that the number of live S. aureus cells was flat and rough reference surfaces. Our micro/nanofabrication process is a scalable approach based on cost-efficient self-organization and provides potential for further developing functional surfaces to study the behavior of microbes on nanoscale topographies.

  2. Electrokinetics on superhydrophobic surfaces

    International Nuclear Information System (INIS)

    Papadopoulos, Periklis; Deng Xu; Vollmer, Doris; Butt, Hans-Jürgen

    2012-01-01

    On a superhydrophobic surface a liquid is exposed to a large air-water interface. The reduced wall friction is expected to cause a higher electro-osmotic mobility. On the other hand, the low charge density of a superhydrophobic surface reduces the electro-osmotic mobility. Due to a lack of experimental data it has not been clear so far whether the reduced wall friction or the reduced charge density dominate the electrokinetic mobilities. To separate the relative contributions of electrophoresis and electro-osmosis, the mobilities of colloids on a negatively charged hydrophilic, a superhydrophobic (Cassie) and a partially hydrophilized superhydrophobic (Cassie composite) coating were measured. To vary the charge density as well as its sign with respect to those of the colloids the partially hydrophilized surfaces were coated with polyelectrolytes. We analyzed the electrokinetic mobilities of negatively charged polystyrene colloids dispersed in aqueous medium on porous hydrophilic and superhydrophobic surfaces by confocal laser scanning electron microscopy. In all cases, the external electric field was parallel to the surface. The total electrokinetic mobilities on the superhydrophobic (Cassie) and negatively charged partially hydrophilized (Cassie composite) surfaces were similar, showing that electro-osmosis is small compared to electrophoresis. The positively charged Cassie composite surfaces tend to ‘trap’ the colloids due to attracting electrostatic interactions and rough morphology, reducing the mobility. Thus, either the charge density of the coatings in the Cassie composite state or its slip length is too low to enhance electro-osmosis.

  3. Plasma-surface interactions

    International Nuclear Information System (INIS)

    Goeckner, M J; Nelson, C T; Sant, S P; Jindal, A K; Joseph, E A; Zhou, B S; Padron-Wells, G; Jarvis, B; Pierce, R; Overzet, L J

    2008-01-01

    Materials processing is at a crossroads. Currently a large fraction of industrially viable materials processing is via plasmas. Until recently it has been economical to just examine the influence the plasma properties on the desired surface processes and through this ultimately optimize manufacturing. For example, it is well known that the surface processes (etch or deposition), occur in the top few mono-layers of the surface. Thus, in film growth one requires that molecules from the gas-phase land and bond on the surface. However as processing has reached the nano-scale, development of viable processes has become more and more difficult. In part, this is because of all of the free parameters that exist in plasmas. To overcome this economic issue, tool vendors and semiconductor companies have turned to complex computational models of processing plasmas. For those models to work, one requires a through understanding of all of the gas-phase and surface-phase processes that are exhibited in plasmas. Unfortunately, these processes, particularly those at the surface, are not well understood. In this article we describe a viable model of the surface-phase based on cross sections for processes that occur. While originally developed of fluorocarbon systems, the model also appears to be applicable to hydrocarbon systems.

  4. Plasma-surface interactions

    Energy Technology Data Exchange (ETDEWEB)

    Goeckner, M J; Nelson, C T; Sant, S P; Jindal, A K; Joseph, E A; Zhou, B S; Padron-Wells, G; Jarvis, B; Pierce, R; Overzet, L J [Department of Electrical Engineering, University of Texas at Dallas (United States)], E-mail: goeckner@utdallas.edu

    2008-10-01

    Materials processing is at a crossroads. Currently a large fraction of industrially viable materials processing is via plasmas. Until recently it has been economical to just examine the influence the plasma properties on the desired surface processes and through this ultimately optimize manufacturing. For example, it is well known that the surface processes (etch or deposition), occur in the top few mono-layers of the surface. Thus, in film growth one requires that molecules from the gas-phase land and bond on the surface. However as processing has reached the nano-scale, development of viable processes has become more and more difficult. In part, this is because of all of the free parameters that exist in plasmas. To overcome this economic issue, tool vendors and semiconductor companies have turned to complex computational models of processing plasmas. For those models to work, one requires a through understanding of all of the gas-phase and surface-phase processes that are exhibited in plasmas. Unfortunately, these processes, particularly those at the surface, are not well understood. In this article we describe a viable model of the surface-phase based on cross sections for processes that occur. While originally developed of fluorocarbon systems, the model also appears to be applicable to hydrocarbon systems.

  5. Surface science techniques

    CERN Document Server

    Walls, JM

    2013-01-01

    This volume provides a comprehensive and up to the minute review of the techniques used to determine the nature and composition of surfaces. Originally published as a special issue of the Pergamon journal Vacuum, it comprises a carefully edited collection of chapters written by specialists in each of the techniques and includes coverage of the electron and ion spectroscopies, as well as the atom-imaging methods such as the atom probe field ion microscope and the scanning tunnelling microscope. Surface science is an important area of study since the outermost surface layers play a crucial role

  6. Surface modes in physics

    CERN Document Server

    Sernelius, Bo E

    2011-01-01

    Electromagnetic surface modes are present at all surfaces and interfaces between material of different dielectric properties. These modes have very important effects on numerous physical quantities: adhesion, capillary force, step formation and crystal growth, the Casimir effect etc. They cause surface tension and wetting and they give rise to forces which are important e.g. for the stability of colloids.This book is a useful and elegant approach to the topic, showing how the concept of electromagnetic modes can be developed as a unifying theme for a range of condensed matter physics. The

  7. Localized Acoustic Surface Modes

    KAUST Repository

    Farhat, Mohamed

    2015-08-04

    We introduce the concept of localized acoustic surface modes (ASMs). We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  8. Surface physics : experimental

    International Nuclear Information System (INIS)

    Padalia, B.D.

    1978-01-01

    In this report, discussion is confined to some important ultra high vacuum surface techniques such as ultra-violet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and the low energy electron diffraction (LEED). An attempt is made to cover the basic principles and the experimental details of XPS and AES. Selected examples illustrating the potentialities of the above techniques to solve the important basic as well as applied problems relating to surfaces are presented. Salient features of the available commercial machines in which UPS, AES and LEED are combined to facilitate surface examination sequentially or simultaneously under identical experimental conditions are indicated. (auth.)

  9. Architectural Knitted Surfaces

    DEFF Research Database (Denmark)

    Mossé, Aurélie

    2010-01-01

    WGSN reports from the Architectural Knitted Surfaces workshop recently held at ShenkarCollege of Engineering and Design, Tel Aviv, which offered a cutting-edge insight into interactive knitted surfaces. With the increasing role of smart textiles in architecture, the Architectural Knitted Surfaces...... workshop brought together architects and interior and textile designers to highlight recent developments in intelligent knitting. The five-day workshop was led by architects Ayelet Karmon and Mette Ramsgaard Thomsen, together with Amir Cang and Eyal Sheffer from the Knitting Laboratory, in collaboration...

  10. Nonlinear surface electromagnetic phenomena

    CERN Document Server

    Ponath, H-E

    1991-01-01

    In recent years the physics of electromagnetic surface phenomena has developed rapidly, evolving into technologies for communications and industry, such as fiber and integrated optics. The variety of phenomena based on electromagnetism at surfaces is rich and this book was written with the aim of summarizing the available knowledge in selected areas of the field. The book contains reviews written by solid state and optical physicists on the nonlinear interaction of electromagnetic waves at and with surfaces and films. Both the physical phenomena and some potential applications are

  11. Surface Weather Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Surface Weather Observation Collection consists primarily of hourly, synoptic, daily, and monthly forms submitted to the archive by the National Weather Service...

  12. Uruguay - Surface Weather Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surface weather observation forms for 26 stations in Uruguay. Period of record 1896-2005, with two to eight observations per day. Files created through a...

  13. Iowa Bedrock Surface Elevation

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This Digital Elevation Model (DEM) of the bedrock surface elevation in Iowa was compiled using all available data, principally information from GEOSAM, supplemented...

  14. Paneling architectural freeform surfaces

    KAUST Repository

    Eigensatz, Michael; Kilian, Martin; Schiftner, Alexander; Mitra, Niloy J.; Pottmann, Helmut; Pauly, Mark

    2010-01-01

    with a selected technology at reasonable cost, while meeting the design intent and achieving the desired aesthetic quality of panel layout and surface smoothness. The production of curved panels is mostly based on molds. Since the cost of mold fabrication

  15. Vortices on hyperbolic surfaces

    International Nuclear Information System (INIS)

    Manton, Nicholas S; Rink, Norman A

    2010-01-01

    It is shown that Abelian Higgs vortices on a hyperbolic surface M can be constructed geometrically from holomorphic maps f: M → N, where N is also a hyperbolic surface. The fields depend on f and on the metrics of M and N. The vortex centres are the ramification points, where the derivative of f vanishes. The magnitude of the Higgs field measures the extent to which f is locally an isometry. Witten's construction of vortices on the hyperbolic plane is rederived, and new examples of vortices on compact surfaces and on hyperbolic surfaces of revolution are obtained. The interpretation of these solutions as SO(3)-invariant, self-dual SU(2) Yang-Mills fields on R 4 is also given.

  16. Land Surface Weather Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — METAR is the international standard code format for hourly surface weather observations. The acronym roughly translates from French as Aviation Routine Weather...

  17. Average nuclear surface properties

    International Nuclear Information System (INIS)

    Groote, H. von.

    1979-01-01

    The definition of the nuclear surface energy is discussed for semi-infinite matter. This definition is extended also for the case that there is a neutron gas instead of vacuum on the one side of the plane surface. The calculations were performed with the Thomas-Fermi Model of Syler and Blanchard. The parameters of the interaction of this model were determined by a least squares fit to experimental masses. The quality of this fit is discussed with respect to nuclear masses and density distributions. The average surface properties were calculated for different particle asymmetry of the nucleon-matter ranging from symmetry beyond the neutron-drip line until the system no longer can maintain the surface boundary and becomes homogeneous. The results of the calculations are incorporated in the nuclear Droplet Model which then was fitted to experimental masses. (orig.)

  18. Mexico - Surface Weather Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Mexican Surface Daily Observations taken at 94 observatories located throughout Mexico, beginning in 1872 and going up through 1981. The data resided on paper...

  19. Switching between pitch surfaces

    DEFF Research Database (Denmark)

    Rago, Vincenzo; Silva, João R; Brito, João

    2018-01-01

    Soccer training and completion is conventionally practiced on natural grass (NG) or artificial turf (AT). Recently, AT pitches for training / competition, and of unstable surfaces for injury prevention training has increased. Therefore, soccer players are frequently exposed to variations in pitch...... surface during either training or competition. These ground changes may impact physical and physiological responses, adaptations as well as the injury. The aim of this review was to summarize the acute physical and physiological responses, chronic adaptations, and injury risk associated with exercising...... on different pitch surfaces in soccer. Eligible studies were published in English, had pitch surface as an independent variable, and had physical, physiological or epidemiological information as outcome variables. Specific data extracted from the articles included the training response, training adaptations...

  20. Surface vibrational spectroscopy (EELS)

    International Nuclear Information System (INIS)

    Okuyama, Hiroshi

    2006-01-01

    Adsorbed states of hydrogen on metal surfaces have been studied by means of electron energy loss spectroscopy (EELS). In this article, typical spectra and analysis as well as recent development are introduced. (author)

  1. Surface Weather Observations Monthly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surface Weather Observation 1001 Forms is a set of historical manuscript records for the period 1893-1948. The collection includes two very similar form types: Form...

  2. Electron microscopy of surfaces

    International Nuclear Information System (INIS)

    Venables, J.A.

    1981-01-01

    Electron beam techniques used to study clean surfaces and surface processes on a microscopic scale are reviewed. Recent experimental examples and possible future developments are discussed. Special emphasis is given to (i) transmission diffraction and microscopy techniques, including atomic imaging; (ii) Auger microscopy on bulk and thin film samples; (iii) secondary electron microscopy, especially low energy secondaries for work-function imaging and photoelectron imaging; and (iv) reflection electron microscopy and diffraction. (orig.)

  3. Dyakonov surface waves

    DEFF Research Database (Denmark)

    Takayama, Osamu; Crasovan, Lucian Cornel; Johansen, Steffen Kjær

    2008-01-01

    The interface of two semi-infinite media, where at least one of them is a birefringent crystal, supports a special type of surface wave that was predicted theoretically by D'yakonov in 1988. Since then, the properties of such waves, which exist in transparent media only under very special......, the existence of these surface waves in specific material examples is analyzed, discussing the challenge posed by their experimental observation....

  4. Automated galaxy surface photometry

    International Nuclear Information System (INIS)

    Cawson, M.G.M.; Kibblewhite, E.J.; Disney, M.J.; Phillipps, S.

    1987-01-01

    Two-dimensional surface photometry of a very large number of galaxies on a deep Schmidt plate has been obtained using the Automatic Plate Measuring System (APM). A method of photometric calibration, suitable for APM measurements, via pixel-by-pixel comparison with CCD frames of a number of the brighter galaxies is described and its advantages are discussed. The same method is used to demonstrate the consistency of measurement of the APM machine when used for surface photometry. (author)

  5. Surface Relief of Mapping

    Science.gov (United States)

    Costa, Manuel F.; Almeida, Jose B.

    1989-02-01

    We will describe in this communication a noncont act method of measuring surface profile, it does not require any surface preparation, and it can be used with a very large range of surfaces from highly reflecting to non reflecting ones and as complex as textile surfaces. This method is reasonably immune to dispersion and diffraction, which usually make very difficult the application of non contact profilometry methods to a wide range of materials and situations, namely on quality control systems in industrial production lines. The method is based on the horizontal shift of the bright spot on a horizontal surface when this is illuminated with an oblique beam and moved vertically. in order to make the profilometry the sample is swept by an oblique light beam and the bright spot position is compared with a reference position. The bright spot must be as small as possible, particularly in very irregular surfaces; so the light beam diameter must be as small as possible and the incidence angle must not be too small. The sensivity of a system based on this method will be given, mostly, by the reception optical system.

  6. Modification of rubber surface by UV surface grafting

    International Nuclear Information System (INIS)

    Shanmugharaj, A.M.; Kim, Jin Kuk; Ryu, Sung Hun

    2006-01-01

    Rubber surface is subjected to ultraviolet radiation (UV) in the presence of allylamine and radiation sensitizer benzophenone (BP). Fourier transform infrared spectral studies reveal the presence of allylamine on the surface. The presence of irregular needle shapes on the surface as observed in scanning electron micrographs also confirms the polymerized allylamine on the surface. Allylamine coatings have been further confirmed from atomic force microscopy (AFM) analysis. Thermogravimetric analysis (TGA) reveals that allylamine coating on the rubber surface lowers the thermal degradation rate. The contact angle between the water and rubber surface decreases for the modified rubber surface confirming the surface modification due to UV surface grafting

  7. Glycoprotein on cell surfaces

    International Nuclear Information System (INIS)

    Muramatsu, T.

    1975-01-01

    There are conjugated polysaccharides in cell membranes and outside of animal cells, and they play important role in the control of cell behavior. In this paper, the studies on the glycoprotein on cell surfaces are reported. It was found that the glycoprotein on cell surfaces have both N-glycoside type and O-glycoside type saccharic chains. Therefore it can be concluded that the basic structure of the saccharic chains in the glycoprotein on cell surfaces is similar to that of blood serum and body fluid. The main glycoprotein in the membranes of red blood corpuscles has been studied most in detail, and it also has both types of saccharic chains. The glycoprotein in liver cell membranes was found to have only the saccharic chains of acid type and to be in different pattern from that in endoplasmic reticula and nuclear membranes, which also has the saccharic chains of neutral type. The structure of the saccharic chains of H-2 antigen, i.e. the peculiar glycoprotein on the surfaces of lymph system cells, has been studied, and it is similar to the saccharic chains of glycoprotein in blood serum. The saccharic chain structures of H-2 antigen and TL antigen are different. TL, H-2 (D), Lna and H-2 (K) are the glycoprotein on cell surfaces, and are independent molecules. The analysis of the saccharic chain patterns on cell surfaces was carried out, and it was shown that the acid type saccharic chains were similar to those of ordinary glycoprotein, because the enzyme of pneumococci hydrolyzed most of the acid type saccharic chains. The change of the saccharic chain patterns of glycoprotein on cell surfaces owing to canceration and multiplication is complex matter. (Kako, I.)

  8. Mars Surface Environmental Issues

    Science.gov (United States)

    Charles, John

    2002-01-01

    Planetary exploration by astronauts will require extended periods of habitation on a planet's surface, under the influence of environmental factors that are different from those of Earth and the spacecraft that delivered the crew to the planet. Human exploration of Mars, a possible near-term planetary objective, can be considered a challenging scenario. Mission scenarios currently under consideration call for surface habitation periods of from 1 to 18 months on even the earliest expeditions. Methods: Environmental issues associated with Mars exploration have been investigated by NASA and the National Space Biomedical Research Institute (NSBRI) as part of the Bioastronautics Critical Path Roadmap Project (see http ://criticalpath.jsc.nasa.gov). Results: Arrival on Mars will immediately expose the crew to gravity only 38% of that at Earth's surface in possibly the first prolonged exposure to gravity other than the 1G of Earth's surface and the zero G of weightless space flight, with yet unknown effects on crew physiology. The radiation at Mars' surface is not well documented, although the planet's bulk and even its thin atmosphere may moderate the influx of galactic cosmic radiation and energetic protons from solar flares. Secondary radiation from activated components of the soil must also be considered. Ultrafine and larger respirable and nonrespirable particles in Martian dust introduced into the habitat after surface excursions may induce pulmonary inflammation exacerbated by the additive reactive and oxidizing nature of the dust. Stringent decontamination cannot eliminate mechanical and corrosive effects of the dust on pressure suits and exposed machinery. The biohazard potential of putative indigenous Martian microorganisms may be assessed by comparison with analog environments on Earth. Even in their absence, human microorganisms, if not properly controlled, can be a threat to the crew's health. Conclusions: Mars' surface offers a substantial challenge to the

  9. Surface chemistry theory and applications

    CERN Document Server

    Bikerman, J J

    2013-01-01

    Surface Chemistry Theory and Applications focuses on liquid-gas, liquid-liquid, solid-gas, solid-liquid, and solid-solid surfaces. The book first offers information on liquid-gas surfaces, including surface tension, measurement of surface tension, rate of capillarity rise, capillary attraction, bubble pressure and pore size, and surface tension and temperature. The text then ponders on liquid-liquid and solid-gas surfaces. Discussions focus on surface energy of solids, surface roughness and cleanness, adsorption of gases and vapors, adsorption hysteresis, interfacial tension, and interfacial t

  10. Smooth surfaces from bilinear patches: Discrete affine minimal surfaces

    KAUST Repository

    Kä ferbö ck, Florian; Pottmann, Helmut

    2013-01-01

    Motivated by applications in freeform architecture, we study surfaces which are composed of smoothly joined bilinear patches. These surfaces turn out to be discrete versions of negatively curved affine minimal surfaces and share many properties

  11. Viscoelastic Surface Waves

    Science.gov (United States)

    Borcherdt, R. D.

    2007-12-01

    General theoretical solutions for Rayleigh- and Love-Type surface waves in viscoelastic media describe physical characteristics of the surface waves in elastic as well as anelastic media with arbitrary amounts of intrinsic absorption. In contrast to corresponding physical characteristics for Rayleigh waves in elastic media, Rayleigh- Type surface waves in anelastic media demonstrate; 1) tilt of the particle motion orbit that varies with depth, and 2) amplitude and volumetric strain distributions with superimposed sinusoidal variations that decay exponentially with depth. Each characteristic is dependent on the amount of intrinsic absorption and the chosen model of viscoelasticity. Distinguishing characteristics of anelastic Love-Type surface waves include: 1) dependencies of the wave speed and absorption coefficient on the chosen model and amount of intrinsic absorption and frequency, and 2) superimposed sinusoidal amplitude variations with an exponential decay with depth. Numerical results valid for a variety of viscoelastic models provide quantitative estimates of the physical characteristics of both types of viscoelastic surface waves appropriate for interpretations pertinent to models of earth materials ranging from low-loss in the crust to moderate- and high-loss in water-saturated soils.

  12. Iron oxide surfaces

    Science.gov (United States)

    Parkinson, Gareth S.

    2016-03-01

    The current status of knowledge regarding the surfaces of the iron oxides, magnetite (Fe3O4), maghemite (γ-Fe2O3), haematite (α-Fe2O3), and wüstite (Fe1-xO) is reviewed. The paper starts with a summary of applications where iron oxide surfaces play a major role, including corrosion, catalysis, spintronics, magnetic nanoparticles (MNPs), biomedicine, photoelectrochemical water splitting and groundwater remediation. The bulk structure and properties are then briefly presented; each compound is based on a close-packed anion lattice, with a different distribution and oxidation state of the Fe cations in interstitial sites. The bulk defect chemistry is dominated by cation vacancies and interstitials (not oxygen vacancies) and this provides the context to understand iron oxide surfaces, which represent the front line in reduction and oxidation processes. Fe diffuses in and out from the bulk in response to the O2 chemical potential, forming sometimes complex intermediate phases at the surface. For example, α-Fe2O3 adopts Fe3O4-like surfaces in reducing conditions, and Fe3O4 adopts Fe1-xO-like structures in further reducing conditions still. It is argued that known bulk defect structures are an excellent starting point in building models for iron oxide surfaces. The atomic-scale structure of the low-index surfaces of iron oxides is the major focus of this review. Fe3O4 is the most studied iron oxide in surface science, primarily because its stability range corresponds nicely to the ultra-high vacuum environment. It is also an electrical conductor, which makes it straightforward to study with the most commonly used surface science methods such as photoemission spectroscopies (XPS, UPS) and scanning tunneling microscopy (STM). The impact of the surfaces on the measurement of bulk properties such as magnetism, the Verwey transition and the (predicted) half-metallicity is discussed. The best understood iron oxide surface at present is probably Fe3O4(100); the structure is

  13. Surface-water surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Saldi, K.A.; Dirkes, R.L.; Blanton, M.L.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the Surface water on and near the Hanford Site is monitored to determine the potential effects of Hanford operations. Surface water at Hanford includes the Columbia River, riverbank springs, ponds located on the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site. Columbia River sediments are also included in this discussion. Tables 5.3.1 and 5.3.2 summarize the sampling locations, sample types, sampling frequencies, and sample analyses included in surface-water surveillance activities during 1994. Sample locations are also identified in Figure 5.3.1. This section describes the surveillance effort and summarizes the results for these aquatic environments. Detailed analytical results are reported by Bisping (1995).

  14. Surface states and spectra

    International Nuclear Information System (INIS)

    Jaksic, V.; Last, Y.; California Inst. of Tech., Pasadena, CA

    2001-01-01

    Let Z + d+1 =Z d x Z + , let H 0 be the discrete Laplacian on the Hilbert space l 2 (Z + d+1 ) with a Dirichlet boundary condition, and let V be a potential supported on the boundary ∂Z + d+1 . We introduce the notions of surface states and surface spectrum of the operator H=H 0 +V and explore their properties. Our main result is that if the potential V is random and if the disorder is either large or small enough, then in dimension two H has no surface spectrum on σ(H 0 ) with probability one. To prove this result we combine Aizenman-Molchanov theory with techniques of scattering theory. (orig.)

  15. Cryogenic surface ion traps

    International Nuclear Information System (INIS)

    Niedermayr, M.

    2015-01-01

    Microfabricated surface traps are a promising architecture to realize a scalable quantum computer based on trapped ions. In principle, hundreds or thousands of surface traps can be located on a single substrate in order to provide large arrays of interacting ions. To this end, trap designs and fabrication methods are required that provide scalable, stable and reproducible ion traps. This work presents a novel surface-trap design developed for cryogenic applications. Intrinsic silicon is used as the substrate material of the traps. The well-developed microfabrication and structuring methods of silicon are utilized to create simple and reproducible traps. The traps were tested and characterized in a cryogenic setup. Ions could be trapped and their life time and motional heating were investigated. Long ion lifetimes of several hours were observed and the measured heating rates were reproducibly low at around 1 phonon per second at a trap frequency of 1 MHz. (author) [de

  16. Responsive acoustic surfaces

    DEFF Research Database (Denmark)

    Peters, Brady; Tamke, Martin; Nielsen, Stig Anton

    2011-01-01

    Acoustic performance is defined by the parameter of reverberation time; however, this does not capture the acoustic experience in some types of open plan spaces. As many working and learning activities now take place in open plan spaces, it is important to be able to understand and design...... for the acoustic conditions of these spaces. This paper describes an experimental research project that studied the design processes necessary to design for sound. A responsive acoustic surface was designed, fabricated and tested. This acoustic surface was designed to create specific sonic effects. The design...... was simulated using custom integrated acoustic software and also using Odeon acoustic analysis software. The research demonstrates a method for designing space- and sound-defining surfaces, defines the concept of acoustic subspace, and suggests some new parameters for defining acoustic subspaces....

  17. From analysis to surface

    DEFF Research Database (Denmark)

    Bemman, Brian; Meredith, David

    it with a “ground truth” analysis of the same music pro- duced by a human expert (see, in particular, [5]). In this paper, we explore the problem of generating an encoding of the musical surface of a work automatically from a systematic encoding of an analysis. The ability to do this depends on one having...... an effective (i.e., comput- able), correct and complete description of some aspect of the structure of the music. Generating the surface struc- ture of a piece from an analysis in this manner serves as a proof of the analysis' correctness, effectiveness and com- pleteness. We present a reductive analysis......In recent years, a significant body of research has focused on developing algorithms for computing analyses of mu- sical works automatically from encodings of these works' surfaces [3,4,7,10,11]. The quality of the output of such analysis algorithms is typically evaluated by comparing...

  18. Surface-water surveillance

    International Nuclear Information System (INIS)

    Saldi, K.A.; Dirkes, R.L.; Blanton, M.L.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report summarizes the Surface water on and near the Hanford Site is monitored to determine the potential effects of Hanford operations. Surface water at Hanford includes the Columbia River, riverbank springs, ponds located on the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site. Columbia River sediments are also included in this discussion. Tables 5.3.1 and 5.3.2 summarize the sampling locations, sample types, sampling frequencies, and sample analyses included in surface-water surveillance activities during 1994. Sample locations are also identified in Figure 5.3.1. This section describes the surveillance effort and summarizes the results for these aquatic environments. Detailed analytical results are reported by Bisping (1995)

  19. Photochemistry on solid surfaces

    CERN Document Server

    Matsuura, T

    1989-01-01

    The latest developments in photochemistry on solid surfaces, i.e. photochemistry in heterogeneous systems, including liquid crystallines, are brought together for the first time in a single volume. Distinguished photochemists from various fields have contributed to the book which covers a number of important applications: molecular photo-devices for super-memory, photochemical vapor deposition to produce thin-layered electronic semiconducting materials, sensitive optical media, the control of photochemical reactions pathways, etc. Photochemistry on solid surfaces is now a major field and this

  20. Surface and nanomolecular catalysis

    CERN Document Server

    Richards, Ryan

    2006-01-01

    Using new instrumentation and experimental techniques that allow scientists to observe chemical reactions and molecular properties at the nanoscale, the authors of Surface and Nanomolecular Catalysis reveal new insights into the surface chemistry of catalysts and the reaction mechanisms that actually occur at a molecular level during catalysis. While each chapter contains the necessary background and explanations to stand alone, the diverse collection of chapters shows how developments from various fields each contributed to our current understanding of nanomolecular catalysis as a whole. The

  1. Solid lubricants and surfaces

    CERN Document Server

    Braithwaite, E R

    1964-01-01

    Solid Lubricants and Surfaces deals with the theory and use of solid lubricants, particularly in colloidal form. Portions of this book are devoted to graphite and molybdenum disulfides, which are widely used solid lubricants in colloidal form. An extensive literature on the laboratory examination of hundreds of solids as potential lubricants is also provided in this text. Other topics discussed include the metals and solid lubricants; techniques for examining surfaces; other solid lubricants; metal shaping; and industrial uses of solid-lubricant dispersions. This publication is beneficial to e

  2. Surface science techniques

    CERN Document Server

    Bracco, Gianangelo

    2013-01-01

    The book describes the experimental techniques employed to study surfaces and interfaces. The emphasis is on the experimental method. Therefore all chapters start with an introduction of the scientific problem, the theory necessary to understand how the technique works and how to understand the results. Descriptions of real experimental setups, experimental results at different systems are given to show both the strength and the limits of the technique. In a final part the new developments and possible extensions of the techniques are presented. The included techniques provide microscopic as well as macroscopic information. They cover most of the techniques used in surface science.

  3. Photometric Lunar Surface Reconstruction

    Science.gov (United States)

    Nefian, Ara V.; Alexandrov, Oleg; Morattlo, Zachary; Kim, Taemin; Beyer, Ross A.

    2013-01-01

    Accurate photometric reconstruction of the Lunar surface is important in the context of upcoming NASA robotic missions to the Moon and in giving a more accurate understanding of the Lunar soil composition. This paper describes a novel approach for joint estimation of Lunar albedo, camera exposure time, and photometric parameters that utilizes an accurate Lunar-Lambertian reflectance model and previously derived Lunar topography of the area visualized during the Apollo missions. The method introduced here is used in creating the largest Lunar albedo map (16% of the Lunar surface) at the resolution of 10 meters/pixel.

  4. Surfing surface gravity waves

    Science.gov (United States)

    Pizzo, Nick

    2017-11-01

    A simple criterion for water particles to surf an underlying surface gravity wave is presented. It is found that particles travelling near the phase speed of the wave, in a geometrically confined region on the forward face of the crest, increase in speed. The criterion is derived using the equation of John (Commun. Pure Appl. Maths, vol. 6, 1953, pp. 497-503) for the motion of a zero-stress free surface under the action of gravity. As an example, a breaking water wave is theoretically and numerically examined. Implications for upper-ocean processes, for both shallow- and deep-water waves, are discussed.

  5. Hyperpolarized Nanodiamond Surfaces.

    Science.gov (United States)

    Rej, Ewa; Gaebel, Torsten; Waddington, David E J; Reilly, David J

    2017-01-11

    The widespread use of nanodiamond as a biomedical platform for drug-delivery, imaging, and subcellular tracking applications stems from its nontoxicity and unique quantum mechanical properties. Here, we extend this functionality to the domain of magnetic resonance, by demonstrating that the intrinsic electron spins on the nanodiamond surface can be used to hyperpolarize adsorbed liquid compounds at low fields and room temperature. By combining relaxation measurements with hyperpolarization, spins on the surface of the nanodiamond can be distinguished from those in the bulk liquid. These results are likely of use in signaling the controlled release of pharmaceutical payloads.

  6. Organometallic chemistry of metal surfaces

    International Nuclear Information System (INIS)

    Muetterties, E.L.

    1981-06-01

    The organometallic chemistry of metal surfaces is defined as a function of surface crystallography and of surface composition for a set of cyclic hydrocarbons that include benzene, toluene, cyclohexadienes, cyclohexene, cyclohexane, cyclooctatetraene, cyclooctadienes, cyclooctadiene, cycloheptatriene and cyclobutane. 12 figures

  7. Wetting of real surfaces

    CERN Document Server

    Bormashenko, Edward Yu

    2013-01-01

    The problem of wetting and drop dynamics on various surfaces is very interesting from both the scientificas well as thepractical viewpoint, and subject of intense research.The results are scattered across papers in journals, sothis workwill meet the need for a unifying, comprehensive work.

  8. Optimization of surface maintenance

    International Nuclear Information System (INIS)

    Oeverland, E.

    1990-01-01

    The present conference paper deals with methods of optimizing the surface maintenance of steel-made offshore installations. The paper aims at identifying important approaches to the problems regarding the long-range planning of an economical and cost effective maintenance program. The methods of optimization are based on the obtained experiences from the maintenance of installations on the Norwegian continental shelf. 3 figs

  9. Paneling architectural freeform surfaces

    KAUST Repository

    Eigensatz, Michael

    2010-07-26

    The emergence of large-scale freeform shapes in architecture poses big challenges to the fabrication of such structures. A key problem is the approximation of the design surface by a union of patches, socalled panels, that can be manufactured with a selected technology at reasonable cost, while meeting the design intent and achieving the desired aesthetic quality of panel layout and surface smoothness. The production of curved panels is mostly based on molds. Since the cost of mold fabrication often dominates the panel cost, there is strong incentive to use the same mold for multiple panels. We cast the major practical requirements for architectural surface paneling, including mold reuse, into a global optimization framework that interleaves discrete and continuous optimization steps to minimize production cost while meeting user-specified quality constraints. The search space for optimization is mainly generated through controlled deviation from the design surface and tolerances on positional and normal continuity between neighboring panels. A novel 6-dimensional metric space allows us to quickly compute approximate inter-panel distances, which dramatically improves the performance of the optimization and enables the handling of complex arrangements with thousands of panels. The practical relevance of our system is demonstrated by paneling solutions for real, cutting-edge architectural freeform design projects. © 2010 ACM.

  10. Dynamical triangulated fermionic surfaces

    International Nuclear Information System (INIS)

    Ambjoern, J.; Varsted, S.

    1990-12-01

    We perform Monte Carlo simulations of randomly triangulated random surfaces which have fermionic world-sheet scalars θ i associated with each vertex i in addition to the usual bosonic world-sheet scalar χ i μ . The fermionic degrees of freedom force the internal metrics of the string to be less singular than the internal metric of the pure bosonic string. (orig.)

  11. Paneling architectural freeform surfaces

    KAUST Repository

    Eigensatz, Michael

    2010-07-25

    The emergence of large-scale freeform shapes in architecture poses big challenges to the fabrication of such structures. A key problem is the approximation of the design surface by a union of patches, so-called panels, that can be manufactured with a selected technology at reasonable cost, while meeting the design intent and achieving the desired aesthetic quality of panel layout and surface smoothness. The production of curved panels is mostly based on molds. Since the cost of mold fabrication often dominates the panel cost, there is strong incentive to use the same mold for multiple panels. We cast the major practical requirements for architectural surface paneling, including mold reuse, into a global optimization framework that interleaves discrete and continuous optimization steps to minimize production cost while meeting user-specified quality constraints. The search space for optimization is mainly generated through controlled deviation from the design surface and tolerances on positional and normal continuity between neighboring panels. A novel 6-dimensional metric space allows us to quickly compute approximate inter-panel distances, which dramatically improves the performance of the optimization and enables the handling of complex arrangements with thousands of panels. The practical relevance of our system is demonstrated by paneling solutions for real, cutting-edge architectural freeform design projects.

  12. Music Mixing Surface

    DEFF Research Database (Denmark)

    Gelineck, Steven; Büchert, Morten; Andersen, Jesper

    2013-01-01

    This paper presents a multi-touch based interface for mixing music. The goal of the interface is to provide users with a more intuitive control of the music mix by implementing the so-called stage metaphor control scheme, which is especially suitable for multi-touch surfaces. Specifically, we...

  13. Surface segregation during irradiation

    International Nuclear Information System (INIS)

    Rehn, L.E.; Lam, N.Q.

    1985-10-01

    Gibbsian adsorption is known to alter the surface composition of many alloys. During irradiation, four additional processes that affect the near-surface alloy composition become operative: preferential sputtering, displacement mixing, radiation-enhanced diffusion and radiation-induced segregation. Because of the mutual competition of these five processes, near-surface compositional changes in an irradiation environment can be extremely complex. Although ion-beam induced surface compositional changes were noted as long as fifty years ago, it is only during the past several years that individual mechanisms have been clearly identified. In this paper, a simple physical description of each of the processes is given, and selected examples of recent important progress are discussed. With the notable exception of preferential sputtering, it is shown that a reasonable qualitative understanding of the relative contributions from the individual processes under various irradiation conditions has been attained. However, considerably more effort will be required before a quantitative, predictive capability can be achieved. 29 refs., 8 figs

  14. Predictive Surface Complexation Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Sverjensky, Dimitri A. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Earth and Planetary Sciences

    2016-11-29

    Surface complexation plays an important role in the equilibria and kinetics of processes controlling the compositions of soilwaters and groundwaters, the fate of contaminants in groundwaters, and the subsurface storage of CO2 and nuclear waste. Over the last several decades, many dozens of individual experimental studies have addressed aspects of surface complexation that have contributed to an increased understanding of its role in natural systems. However, there has been no previous attempt to develop a model of surface complexation that can be used to link all the experimental studies in order to place them on a predictive basis. Overall, my research has successfully integrated the results of the work of many experimentalists published over several decades. For the first time in studies of the geochemistry of the mineral-water interface, a practical predictive capability for modeling has become available. The predictive correlations developed in my research now enable extrapolations of experimental studies to provide estimates of surface chemistry for systems not yet studied experimentally and for natural and anthropogenically perturbed systems.

  15. Surface soil contamination standards

    International Nuclear Information System (INIS)

    Boothe, G.F.

    1979-01-01

    The purpose of this document is to define surface soil contamination limits for radioactive materials below which posting, restrictions and environmental controls are not necessary in order to protect personnel and the environment. The standards can also be used to determine if solid waste or other material is contaminated relative to disposal requirements. The derivation of the standards is given

  16. Paneling architectural freeform surfaces

    KAUST Repository

    Eigensatz, Michael; Kilian, Martin; Schiftner, Alexander; Mitra, Niloy J.; Pottmann, Helmut; Pauly, Mark

    2010-01-01

    The emergence of large-scale freeform shapes in architecture poses big challenges to the fabrication of such structures. A key problem is the approximation of the design surface by a union of patches, socalled panels, that can be manufactured with a

  17. Laser surface cleaning

    International Nuclear Information System (INIS)

    Freiwald, J.G.; Freiwald, D.A.

    1994-01-01

    The objective of this work is a laboratory demonstration that red-lead primer and two-part epoxy paints can be stripped from concrete and metal surfaces using surface cleaning systems based on pulsed-repetition CO 2 lasers. The three goals are to: (1) demonstrate coatings removal, including surface pore cleaning; (2) demonstrate that there is negligible release of ablated contaminants to the environment; and (3) demonstrate that the process will generate negligible amounts of additional waste compared to competing technologies. Phase 1 involved site visits to RMI and Fernald to assess the cleaning issues for buildings and parts. In addition, Phase 1 included detailed designs of a more powerful system for industrial cleaning rates, including laser, articulating optics, ablated-material capture suction nozzle attached to a horizontal raster scanner for floor cleaning, and filtration system. Some concept development is also being done for using robots, and for parts cleaning. In Phase 2 a transportable 6 kW system will be built and tested, with a horizontal surface scanner for cleaning paint from floors. The laboratory tests will again be instrumented. Some concept development will continue for using robots, and for parts cleaning. This report describes Phase 1 results

  18. Tritium-surface interactions

    International Nuclear Information System (INIS)

    Kirkaldy, J.S.

    1983-06-01

    The report deals broadly with tritium-surface interactions as they relate to a fusion power reactor enterprise, viz., the vacuum chamber, first wall, peripherals, pumping, fuel recycling, isotope separation, repair and maintenance, decontamination and safety. The main emphasis is on plasma-surface interactions and the selection of materials for fusion chamber duty. A comprehensive review of the international (particularly U.S.) research and development is presented based upon a literature review (about 1 000 reports and papers) and upon visits to key laboratories, Sandia, Albuquerque, Sandia, Livermore and EGβG Idaho. An inventory of Canadian expertise and facilities for RβD on tritium-surface interactions is also presented. A number of proposals are made for the direction of an optimal Canadian RβD program, emphasizing the importance of building on strength in both the technological and fundamental areas. A compendium of specific projects and project areas is presented dealing primarily with plasma-wall interactions and permeation, anti-permeation materials and surfaces and health, safety and environmental considerations. Potential areas of industrial spinoff are identified

  19. Surface Water in Hawaii

    Science.gov (United States)

    Oki, Delwyn S.

    2003-01-01

    Surface water in Hawaii is a valued resource as well as a potential threat to human lives and property. The surface-water resources of Hawaii are of significant economic, ecologic, cultural, and aesthetic importance. Streams supply more than 50 percent of the irrigation water in Hawaii, and although streams supply only a few percent of the drinking water statewide, surface water is the main source of drinking water in some places. Streams also are a source of hydroelectric power, provide important riparian and instream habitats for many unique native species, support traditional and customary Hawaiian gathering rights and the practice of taro cultivation, and possess valued aesthetic qualities. Streams affect the physical, chemical, and aesthetic quality of receiving waters, such as estuaries, bays, and nearshore waters, which are critical to the tourism-based economy of the islands. Streams in Hawaii pose a danger because of their flashy nature; a stream's stage, or water level, can rise several feet in less than an hour during periods of intense rainfall. Streams in Hawaii are flashy because rainfall is intense, drainage basins are small, basins and streams are steep, and channel storage is limited. Streamflow generated during periods of heavy rainfall has led to loss of property and human lives in Hawaii. Most Hawaiian streams originate in the mountainous interiors of the islands and terminate at the coast. Streams are significant sculptors of the Hawaiian landscape because of the erosive power of the water they convey. In geologically young areas, such as much of the southern part of the island of Hawaii, well-defined stream channels have not developed because the permeability of the surface rocks generally is so high that rainfall infiltrates before flowing for significant distances on the surface. In geologically older areas that have received significant rainfall, streams and mass wasting have carved out large valleys.

  20. Transversal Surfaces of Timelike Ruled Surfaces in Minkowski 3-Space

    OpenAIRE

    Önder, Mehmet

    2012-01-01

    In this study we give definitions and characterizations of transversal surfaces of timelike ruled surfaces. We study some special cases such as the striction curve is a geodesic, an asymptotic line or a line of curvature. Moreover, we obtain developable conditions for transversal surfaces of a timelike ruled surface.

  1. In-surface confinement of topological insulator nanowire surface states

    International Nuclear Information System (INIS)

    Chen, Fan W.; Jauregui, Luis A.; Tan, Yaohua; Manfra, Michael; Klimeck, Gerhard; Chen, Yong P.; Kubis, Tillmann

    2015-01-01

    The bandstructures of [110] and [001] Bi 2 Te 3 nanowires are solved with the atomistic 20 band tight binding functionality of NEMO5. The theoretical results reveal: The popular assumption that all topological insulator (TI) wire surfaces are equivalent is inappropriate. The Fermi velocity of chemically distinct wire surfaces differs significantly which creates an effective in-surface confinement potential. As a result, topological insulator surface states prefer specific surfaces. Therefore, experiments have to be designed carefully not to probe surfaces unfavorable to the surface states (low density of states) and thereby be insensitive to the TI-effects

  2. In-surface confinement of topological insulator nanowire surface states

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Fan W., E-mail: fanchen@purdue.edu [Department of Physics and Astronomy, Purdue, West Lafayette, Indiana 47907 (United States); Network for Computational Nanotechnology, Purdue, West Lafayette, Indiana 47907 (United States); Jauregui, Luis A. [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); Tan, Yaohua [Network for Computational Nanotechnology, Purdue, West Lafayette, Indiana 47907 (United States); School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Manfra, Michael [Department of Physics and Astronomy, Purdue, West Lafayette, Indiana 47907 (United States); School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Klimeck, Gerhard [Network for Computational Nanotechnology, Purdue, West Lafayette, Indiana 47907 (United States); School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); Chen, Yong P. [Department of Physics and Astronomy, Purdue, West Lafayette, Indiana 47907 (United States); School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); Kubis, Tillmann [Network for Computational Nanotechnology, Purdue, West Lafayette, Indiana 47907 (United States)

    2015-09-21

    The bandstructures of [110] and [001] Bi{sub 2}Te{sub 3} nanowires are solved with the atomistic 20 band tight binding functionality of NEMO5. The theoretical results reveal: The popular assumption that all topological insulator (TI) wire surfaces are equivalent is inappropriate. The Fermi velocity of chemically distinct wire surfaces differs significantly which creates an effective in-surface confinement potential. As a result, topological insulator surface states prefer specific surfaces. Therefore, experiments have to be designed carefully not to probe surfaces unfavorable to the surface states (low density of states) and thereby be insensitive to the TI-effects.

  3. In-surface confinement of topological insulator nanowire surface states

    Science.gov (United States)

    Chen, Fan W.; Jauregui, Luis A.; Tan, Yaohua; Manfra, Michael; Klimeck, Gerhard; Chen, Yong P.; Kubis, Tillmann

    2015-09-01

    The bandstructures of [110] and [001] Bi2Te3 nanowires are solved with the atomistic 20 band tight binding functionality of NEMO5. The theoretical results reveal: The popular assumption that all topological insulator (TI) wire surfaces are equivalent is inappropriate. The Fermi velocity of chemically distinct wire surfaces differs significantly which creates an effective in-surface confinement potential. As a result, topological insulator surface states prefer specific surfaces. Therefore, experiments have to be designed carefully not to probe surfaces unfavorable to the surface states (low density of states) and thereby be insensitive to the TI-effects.

  4. Characterisation of surface roughness for ultra-precision freeform surfaces

    International Nuclear Information System (INIS)

    Li Huifen; Cheung, C F; Lee, W B; To, S; Jiang, X Q

    2005-01-01

    Ultra-precision freeform surfaces are widely used in many advanced optics applications which demand for having surface roughness down to nanometer range. Although a lot of research work has been reported on the study of surface generation, reconstruction and surface characterization such as MOTIF and fractal analysis, most of them are focused on axial symmetric surfaces such as aspheric surfaces. Relative little research work has been found in the characterization of surface roughness in ultra-precision freeform surfaces. In this paper, a novel Robust Gaussian Filtering (RGF) method is proposed for the characterisation of surface roughness for ultra-precision freeform surfaces with known mathematic model or a cloud of discrete points. A series of computer simulation and measurement experiments were conducted to verify the capability of the proposed method. The experimental results were found to agree well with the theoretical results

  5. Evaluation of Surface Fatigue Strength Based on Surface Temperature

    Science.gov (United States)

    Deng, Gang; Nakanishi, Tsutomu

    Surface temperature is considered to be an integrated index that is dependent on not only the load and the dimensions at the contact point but also the sliding velocity, rolling velocity, surface roughness, and lubrication conditions. Therefore, the surface durability of rollers and gears can be evaluated more exactly and simply by the use of surface temperature rather than Hertzian stress. In this research, surface temperatures of rollers under different rolling and sliding conditions are measured using a thermocouple. The effects of load P, mean velocity Vm and sliding velocity Vs on surface temperature are clarified. An experimental formula, which expresses the linear relationship between surface temperature and the P0.86Vs1.31Vm-0.83 value, is used to determine surface temperature. By comparing calculated and measured temperature on the tooth surface of a gear, this formula is confirmed to be applicable for gear tooth surface temperature calculation.

  6. Approximation of Surfaces by Cylinders

    DEFF Research Database (Denmark)

    Randrup, Thomas

    1998-01-01

    We present a new method for approximation of a given surface by a cylinder surface. It is a constructive geometric method, leading to a monorail representation of the cylinder surface. By use of a weighted Gaussian image of the given surface, we determine a projection plane. In the orthogonal...

  7. Drop Impact on Superheated Surfaces

    NARCIS (Netherlands)

    Tran, Tuan; Staat, Erik-Jan; Prosperetti, Andrea; Sun, Chao; Lohse, Detlef

    2012-01-01

    At the impact of a liquid droplet on a smooth surface heated above the liquid’s boiling point, the droplet either immediately boils when it contacts the surface (“contact boiling”), or without any surface contact forms a Leidenfrost vapor layer towards the hot surface and bounces back (“gentle film

  8. Parsimonious Surface Wave Interferometry

    KAUST Repository

    Li, Jing

    2017-10-24

    To decrease the recording time of a 2D seismic survey from a few days to one hour or less, we present a parsimonious surface-wave interferometry method. Interferometry allows for the creation of a large number of virtual shot gathers from just two reciprocal shot gathers by crosscoherence of trace pairs, where the virtual surface waves can be inverted for the S-wave velocity model by wave-equation dispersion inversion (WD). Synthetic and field data tests suggest that parsimonious wave-equation dispersion inversion (PWD) gives S-velocity tomograms that are comparable to those obtained from a full survey with a shot at each receiver. The limitation of PWD is that the virtual data lose some information so that the resolution of the S-velocity tomogram can be modestly lower than that of the S-velocity tomogram inverted from a conventional survey.

  9. The surface analysis methods

    International Nuclear Information System (INIS)

    Deville, J.P.

    1998-01-01

    Nowadays, there are a lot of surfaces analysis methods, each having its specificity, its qualities, its constraints (for instance vacuum) and its limits. Expensive in time and in investment, these methods have to be used deliberately. This article appeals to non specialists. It gives some elements of choice according to the studied information, the sensitivity, the use constraints or the answer to a precise question. After having recalled the fundamental principles which govern these analysis methods, based on the interaction between radiations (ultraviolet, X) or particles (ions, electrons) with matter, two methods will be more particularly described: the Auger electron spectroscopy (AES) and x-rays photoemission spectroscopy (ESCA or XPS). Indeed, they are the most widespread methods in laboratories, the easier for use and probably the most productive for the analysis of surface of industrial materials or samples submitted to treatments in aggressive media. (O.M.)

  10. Deformations of surface singularities

    CERN Document Server

    Szilárd, ágnes

    2013-01-01

    The present publication contains a special collection of research and review articles on deformations of surface singularities, that put together serve as an introductory survey of results and methods of the theory, as well as open problems, important examples and connections to other areas of mathematics. The aim is to collect material that will help mathematicians already working or wishing to work in this area to deepen their insight and eliminate the technical barriers in this learning process. This also is supported by review articles providing some global picture and an abundance of examples. Additionally, we introduce some material which emphasizes the newly found relationship with the theory of Stein fillings and symplectic geometry.  This links two main theories of mathematics: low dimensional topology and algebraic geometry. The theory of normal surface singularities is a distinguished part of analytic or algebraic geometry with several important results, its own technical machinery, and several op...

  11. Surface Plasmon Nanophotonics

    CERN Document Server

    Brongersma, Mark L

    2007-01-01

    The development of advanced dielectric photonic structures has enabled tremendous control over the propagation and manipulation of light. Structures such as waveguides, splitters, mixers, and resonators now play a central role in the telecommunications industry. This book will discuss an exciting new class of photonic devices, known as surface plasmon nanophotonic structures. Surface plasmons are easily accessible excitations in metals and semiconductors and involve a collective motion of the conduction electrons. These excitations can be exploited to manipulate electromagnetic waves at optical frequencies ("light") in new ways that are unthinkable in conventional dielectric structures. The field of plasmon nanophotonics is rapidly developing and impacting a wide range of areas including: electronics, photonics, chemistry, biology, and medicine. The book will highlight several exciting new discoveries that have been made, while providing a clear discussion of the underlying physics, the nanofabrication issues...

  12. Surface Plasmon Singularities

    Directory of Open Access Journals (Sweden)

    Gabriel Martínez-Niconoff

    2012-01-01

    Full Text Available With the purpose to compare the physical features of the electromagnetic field, we describe the synthesis of optical singularities propagating in the free space and on a metal surface. In both cases the electromagnetic field has a slit-shaped curve as a boundary condition, and the singularities correspond to a shock wave that is a consequence of the curvature of the slit curve. As prototypes, we generate singularities that correspond to fold and cusped regions. We show that singularities in free space may generate bifurcation effects while plasmon fields do not generate these kinds of effects. Experimental results for free-space propagation are presented and for surface plasmon fields, computer simulations are shown.

  13. Hydrological land surface modelling

    DEFF Research Database (Denmark)

    Ridler, Marc-Etienne Francois

    Recent advances in integrated hydrological and soil-vegetation-atmosphere transfer (SVAT) modelling have led to improved water resource management practices, greater crop production, and better flood forecasting systems. However, uncertainty is inherent in all numerical models ultimately leading...... temperature are explored in a multi-objective calibration experiment to optimize the parameters in a SVAT model in the Sahel. The two satellite derived variables were effective at constraining most land-surface and soil parameters. A data assimilation framework is developed and implemented with an integrated...... and disaster management. The objective of this study is to develop and investigate methods to reduce hydrological model uncertainty by using supplementary data sources. The data is used either for model calibration or for model updating using data assimilation. Satellite estimates of soil moisture and surface...

  14. Parsimonious Surface Wave Interferometry

    KAUST Repository

    Li, Jing; Hanafy, Sherif; Schuster, Gerard T.

    2017-01-01

    To decrease the recording time of a 2D seismic survey from a few days to one hour or less, we present a parsimonious surface-wave interferometry method. Interferometry allows for the creation of a large number of virtual shot gathers from just two reciprocal shot gathers by crosscoherence of trace pairs, where the virtual surface waves can be inverted for the S-wave velocity model by wave-equation dispersion inversion (WD). Synthetic and field data tests suggest that parsimonious wave-equation dispersion inversion (PWD) gives S-velocity tomograms that are comparable to those obtained from a full survey with a shot at each receiver. The limitation of PWD is that the virtual data lose some information so that the resolution of the S-velocity tomogram can be modestly lower than that of the S-velocity tomogram inverted from a conventional survey.

  15. Antibacterial Metallic Touch Surfaces

    Directory of Open Access Journals (Sweden)

    Victor M. Villapún

    2016-08-01

    Full Text Available Our aim is to present a comprehensive review of the development of modern antibacterial metallic materials as touch surfaces in healthcare settings. Initially we compare Japanese, European and US standards for the assessment of antimicrobial activity. The variations in methodologies defined in these standards are highlighted. Our review will also cover the most relevant factors that define the antimicrobial performance of metals, namely, the effect of humidity, material geometry, chemistry, physical properties and oxidation of the material. The state of the art in contact-killing materials will be described. Finally, the effect of cleaning products, including disinfectants, on the antimicrobial performance, either by direct contact or by altering the touch surface chemistry on which the microbes attach, will be discussed. We offer our outlook, identifying research areas that require further development and an overview of potential future directions of this exciting field.

  16. Tumor cell surface proteins

    International Nuclear Information System (INIS)

    Kennel, S.J.; Braslawsky, G.R.; Flynn, K.; Foote, L.J.; Friedman, E.; Hotchkiss, J.A.; Huang, A.H.L.; Lankford, P.K.

    1982-01-01

    Cell surface proteins mediate interaction between cells and their environment. Unique tumor cell surface proteins are being identified and quantified in several tumor systems to address the following questions: (i) how do tumor-specific proteins arise during cell transformation; (ii) can these proteins be used as markers of tumor cell distribution in vivo; (iii) can cytotoxic drugs be targeted specifically to tumor cells using antibody; and (iv) can solid state radioimmunoassay of these proteins provide a means to quantify transformation frequencies. A tumor surface protein of 180,000 M/sub r/ (TSP-180) has been identified on cells of several lung carcinomas of BALB/c mice. TSP-180 was not detected on normal lung tissue, embryonic tissue, or other epithelial or sarcoma tumors, but it was found on lung carcinomas of other strains of mice. Considerable amino acid sequence homology exists among TSP-180's from several cell sources, indicating that TSP-180 synthesis is directed by normal cellular genes although it is not expressed in normal cells. The regulation of synthesis of TSP-180 and its relationship to normal cell surface proteins are being studied. Monoclonal antibodies (MoAb) to TSP-180 have been developed. The antibodies have been used in immunoaffinity chromatography to isolate TSP-180 from tumor cell sources. This purified tumor antigen was used to immunize rats. Antibody produced by these animals reacted at different sites (epitopes) on the TSP-180 molecule than did the original MoAb. These sera and MoAb from these animals are being used to identify normal cell components related to the TSP-180 molecule

  17. Water on graphene surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gordillo, M C [Departamento de Sistemas Fisicos, Quimicos y Naturales, Facultad de Ciencias Experimentales, Universidad Pablo de Olavide, Carretera de Utrera, km 1, E-41013 Sevilla (Spain); Marti, J, E-mail: cgorbar@upo.e, E-mail: jordi.marti@upc.ed [Departament de Fisica i Enginyeria Nuclear, Universitat Politecnica de Catalunya, B4-B5 Campus Nord, E-08034 Barcelona, Catalonia (Spain)

    2010-07-21

    In this paper, we summarize the main results obtained in our group about the behavior of water confined inside or close to different graphene surfaces by means of molecular dynamics simulations. These include the inside and outside of carbon nanotubes, and the confinement inside a slit pore or a single graphene sheet. We paid special attention to some thermodynamical (binding energies), structural (hydrogen-bond distributions) and dynamic (infrared spectra) properties, and their comparison to their bulk counterparts.

  18. Curves and Surfaces

    Science.gov (United States)

    1990-01-01

    joint work with Bj6rn Jawerth and Brad Lucier. Courbes et Surfaces CHAMONIX - MONT BLANC 21-27juin 1990 QUASI-Eh4TERPOIANT’S DE TYPE DE SZASZ ...t) =ect, c > 0, t e lR, et, G(IR,) = (f e C(1R: IlfiI sup ( if (t)I / (p(t), t e IR+) < +oo) L’opdrateur de Szasz -Mirakyan Sn de C,(IR+) dans G[a,b

  19. Fuzzy Riemann surfaces

    International Nuclear Information System (INIS)

    Arnlind, Joakim; Hofer, Laurent; Hoppe, Jens; Bordemann, Martin; Shimada, Hidehiko

    2009-01-01

    We introduce C-Algebras (quantum analogues of compact Riemann surfaces), defined by polynomial relations in non-commutative variables and containing a real parameter that, when taken to zero, provides a classical non-linear, Poisson-bracket, obtainable from a single polynomial C(onstraint) function. For a continuous class of quartic constraints, we explicitly work out finite dimensional representations of the corresponding C-Algebras.

  20. Single Crystal Surfaces

    Science.gov (United States)

    Aguilar-Santillan, Joaquin

    2014-06-01

    The present work studies (0001) Al2O3 and (111) Al2MgO4 wetting with pure molten Al by the sessile drop technique from 1073 K to 1473 K (800 °C to 1200 °C) under Ar at PO2 10-15 Pa. Al pure liquid wets a smooth and chemically homogeneous surface of an inert solid, the wetting driving force ( t, T) can be readily studied when surface solid roughness increases in the system. Both crystals planes (0001) Al2O3 and (111) Al2MgO4 have crystallographic surfaces with identical O-2 crystalline positions however considering Mg2+ content in Al2MgO4 structure may influence a reactive mode. Kinetic models results under similar experimental conditions show that Al wetting on (0001) Al2O3 is less reactive than (111) Al2MgO4, however at >1273 K (1000 °C) (0001) Al2O3 transformation occurs and a transition of wetting improves. The (111) Al2MgO4 and Al system promotes interface formations that slow its wetting process.

  1. Amphoteric surface active agents

    Directory of Open Access Journals (Sweden)

    Eissa, A.M. F.

    1995-10-01

    Full Text Available 2-[trimethyl ammonium, triethyl ammonium, pyridinium and 2-amino pyridinium] alkanoates, four series of surface active agents containing carbon chain C12, C14, C16 and C18carbon atoms, were prepared. Their structures were characterized by microanalysis, infrared (IR and nuclear magnetic resonance (NMR. Surface and interfacial tension, Krafft point, wetting time, emulsification power, foaming height and critical micelle concentration (cmc were determined and a comparative study was made between their chemical structure and surface active properties. Antimicrobial activity of these surfactants was also determined.

    Se prepararon cuatro series de agentes tensioactivos del tipo 2-[trimetil amonio, trietil amonio, piridinio y 2-amino piridinio] alcanoatos, que contienen cadenas carbonadas con C12, C14, C16 y C18 átomos de carbono.
    Se determinaron la tensión superficial e interfacial, el punto de Krafft, el tiempo humectante, el poder de emulsionamiento, la altura espumante y la concentración critica de miscela (cmc y se hizo un estudio comparativo entre la estructura química y sus propiedades tensioactivas. Se determinó también la actividad antimicrobiana de estos tensioactivos. Estas estructuras se caracterizaron por microanálisis, infrarrojo (IR y resonancia magnética nuclear (RMN.

  2. Microplates with adaptive surfaces.

    Science.gov (United States)

    Akbulut, Meshude; Lakshmi, Dhana; Whitcombe, Michael J; Piletska, Elena V; Chianella, Iva; Güven, Olgun; Piletsky, Sergey A

    2011-11-14

    Here we present a new and versatile method for the modification of the well surfaces of polystyrene microtiter plates (microplates) with poly(N-phenylethylene diamine methacrylamide), (poly-NPEDMA). The chemical grafting of poly-NPEDMA to the surface of microplates resulted in the formation of thin layers of a polyaniline derivative bearing pendant methacrylamide double bonds. These were used as the attachment point for various functional polymers through photochemical grafting of various, for example, acrylate and methacrylate, polymers with different functionalities. In a model experiment, we have modified poly-NPEDMA-coated microplates with a small library of polymers containing different functional groups using a two-step approach. In the first step, double bonds were activated by UV irradiation in the presence of N,N-diethyldithiocarbamic acid benzyl ester (iniferter). This enabled grafting of the polymer library in the second step by UV irradiation of solutions of the corresponding monomers in the microplate wells. The uniformity of coatings was confirmed spectrophotometrically, by microscopic imaging and by contact angle measurements (CA). The feasibility of the current technology has been shown by the generation of a small library of polymers grafted to the microplate well surfaces and screening of their affinity to small molecules, such as atrazine, a trio of organic dyes, and a model protein, bovine serum albumin (BSA). The stability of the polymers, reproducibility of measurement, ease of preparation, and cost-effectiveness make this approach suitable for applications in high-throughput screening in the area of materials research.

  3. Mapping stellar surface features

    International Nuclear Information System (INIS)

    Noah, P.V.

    1987-01-01

    New photometric and spectroscopic observations of the RS Canum Venaticorum binaries Sigma Geminorum and UX Arietis are reported along with details of the Doppler-imaging program SPOTPROF. The observations suggest that the starspot activity on Sigma Gem has decreased to 0.05 magnitude in two years. A photometric spot model for September 1984 to January 1985 found that a single spot covering 2% of the surface and 1000 K cooler than the surrounding photosphere could model the light variations. Equivalent-width observations contemporaneous with the photometric observations did not show any significant variations. Line-profile models from SPOTPROF predict that the variation of the equivalent width of the 6393 A Fe I line should be ∼ 1mA. Photometric observations of UX Ari from January 1984 to March 1985 show an 0.3 magnitude variation indicating a large spot group must cover the surface. Contemporaneous spectroscopic observations show asymmetric line profiles. The Doppler imaging and the photometric light-curve models were used in an iterative method to describe the stellar surface-spot distribution and successfully model both the photometric and the spectroscopic variations

  4. Surface roughening under ion bombardment

    International Nuclear Information System (INIS)

    Bhatia, C.S.

    1982-01-01

    Ion bombardment can cause roughening of a surface. Inadequate step coverage and poor adhesion of films on such surfaces are of concern. An extreme case of surface roughening results in cone formation under ion bombardment. The results of the investigation, using scanning electron microscopy, is discussed in terms of the role of (a) embedded particles, (b) impurities and (c) surface migration in cone formation on the target surface. (Auth.)

  5. Radiative heat exchange between surfaces

    International Nuclear Information System (INIS)

    Yener, Y.; Yuncu, H.

    1987-01-01

    The geometrical features of radiative heat exchange between surfaces are discussed first by developing various radiation shape factor relations. The governing equations for enclosures with diffusely emitting and diffusely reflecting surfaces, as well as the equations for enclosures with gray surfaces having specular component of reflectivity are introduced next. Finally, a simplified model for enclosures with isothermal surfaces under the assumption of uniform radiosity over the surfaces is discussed, and various working relations for different conditions are presented

  6. MR imaging of brain surface structures: Surface anatomy scanning

    International Nuclear Information System (INIS)

    Katada, K.; Koga, S.; Asahina, M.; Kanno, T.; Asahina, K.

    1987-01-01

    Preoperative evaluation of brain surface anatomy, including cortical sulci and veins, relative to cerebral and cerebellar lesions is an important subject for surgeons. Until now, no imaging modality existed that allowed direct visualization of brain surface anatomy. A new MR imaging technique (surface anatomy scanning) was developed to visualize brain surface structures. The technique uses a spin-echo pulse sequence with long repetition and echo times, thick sections and a surface coil. Cortical sulci, fissures, veins, and intracranial lesions were clearly identified with this technique. Initial clinical results indicate that surface anatomy scanning is useful for lesion localization and for detailed evaluation of cortical and subcortical lesions

  7. Biomechanical aspects of playing surfaces.

    Science.gov (United States)

    Nigg, B M; Yeadon, M R

    1987-01-01

    The purpose of this paper is to discuss some biomechanical aspects of playing surfaces with special focus on (a) surface induced injuries, (b) methodologies used to assess surfaces and (c) findings from various sports. The paper concentrates primarily on questions related to load on the athlete's body. Data from epidemiological studies suggest strongly that the surface is an important factor in the aetiology of injuries. Injury frequencies are reported to be significantly different for different surfaces in several sports. The methodologies used to assess surfaces with respect to load or performance include material tests and tests using experimental subjects. There is only little correlation between the results of these two approaches. Material tests used in many standardized test procedures are not validated which suggests that one should exercise restraint in the interpretation of these results. Point elastic surfaces are widely studied while area elastic surfaces have received little attention to date. Questions of energy losses on sport surfaces have rarely been studied scientifically.

  8. Surface treatment of zirconia ceramics

    International Nuclear Information System (INIS)

    1980-01-01

    A method of chemically micropitting and/or microcratering at least a portion of a smooth surface of an impervious zirconia-base ceramic is described, comprising (a) contacting the smooth surface with a liquid leachant selected from concentrated sulphuric acid, ammonium bisulphate, alkali metal bisulphates and mixtures thereof at a temperature of at least 250 0 C for a period of time sufficient to effect micropitting and/or microcratering generally uniformly distributed throughout the microstructure of the resultant leached surface; (b) removing the leached surface from contact with the leachant; (c) contacting the leached surface with hydrochloric acid to effect removal from the leached surface of a residue thereon comprising sulphate of metal elements including zirconium in the ceramic; (d) removing the leached surface from contact with the hydrochloric acid; and (e) rinsing the leached surface with water to effect removal of acid residue from that surface. (author)

  9. Surface Plasmon Resonance Biosensor

    Directory of Open Access Journals (Sweden)

    Nina GRIDINA

    2013-02-01

    Full Text Available Performed in this paper is numerical modeling of the angular dependence for light reflectivity R(F in surface plasmon-polariton resonance (SPR realized in Kretschmann geometry when studying the interface gold/suspension of spherical particles (cells in the assumption that the dielectric permittivity of particles suspension is described by the theory of effective medium. It has been shown that availability of suspended particles in solution inevitably results in appearance of an intermediate layer with the ε gradient between gold surface and suspension bulk, as a result of which the SPR angle shifts to lower values. Near the critical angle, the first derivative dR/dF demonstrates a clearly pronounced peak, which allows determining the value for suspension bulk and the gradient in the intermediate layer. Obtained in our experiments were SPR curves for two suspensions of erythrocytes – the dense one (erythrocyte mass after centrifuging and loose solution (whole blood. In the case of erythrocyte mass, fitting the experimental and calculated curves enabled us to quantitatively determine the bulk value for this erythrocyte mass (εb =1.96, thickness of the intermediate layer dm (300…400 nm and gradient in the intermediate layer. On the contrary, the SPR curve for whole blood appeared to be close to that of pure plasma. This fact allows only estimation of the thickness dm~2000...3000 nm as well as minimum ε value in the intermediate layer, which is close to that of plasma (ε = 1.79. Also, discussed is the mechanism of influence of the cell shape near the gold surface on the SPR effect.

  10. Anionic surface binders

    OpenAIRE

    Aljaž-Rožič Mateja; Hočevar Nežka

    2004-01-01

    The MELAMIN Chemical Factory in Kočevje manufactures synthetic resins and binders for the paper industry. Binders based on AKD (alkyl ketene dimer) are produced which are used for binding paper and cardboard in the range of neutral and partially basic pH. Cationic and, lately, anionic binders are mostly used for the bulk binding of paper and board. The possibility of using AKD binders on paper or board surfaces is presented. In this case partially cationic AKD binders may be applied. When opt...

  11. Distributed Surface Force

    Science.gov (United States)

    2014-06-01

    surface missile SSN nuclear powered attack submarine ST Singapore Technologies T-AKE Lewis and Clarke class TDSI Temasek Defense Systems Institute TRL...total of 313 (Department of the Navy N8 Department 2013). This 306-ship plan includes 12 SSBNs, 48 SSNs , 11 aircraft carriers, 88 cruisers and...MoCil • • West Reef Barque Canada Stloal frinc2 of wales Bank • Reef fat Grair9r Bani< Aneoyna Cltf •Mari\\eles • • • • Nlenwl Bank Ardaser n Dalas

  12. Multilayer Relaxation and Surface Energies of Metallic Surfaces

    Science.gov (United States)

    Bozzolo, Guillermo; Rodriguez, Agustin M.; Ferrante, John

    1994-01-01

    The perpendicular and parallel multilayer relaxations of fcc (210) surfaces are studied using equivalent crystal theory (ECT). A comparison with experimental and theoretical results is made for AI(210). The effect of uncertainties in the input parameters on the magnitudes and ordering of surface relaxations for this semiempirical method is estimated. A new measure of surface roughness is proposed. Predictions for the multilayer relaxations and surface energies of the (210) face of Cu and Ni are also included.

  13. Concepts in surface physics

    CERN Document Server

    Desjonquères, M -C

    1993-01-01

    This textbook is intended as an introduction to surface science for graduate students. It began as a course of lectures that we gave at the University of Paris (Orsay). Its main objectives are twofold: to provide the reader with a compre­ hensive presentation of the basic principles and concepts of surface physics and to show the usefulness of these concepts in the real world by referring to experiments. It starts at a rather elementary level since it only requires a knowledge of solid state physics, quantum mechanics, thermodynamics and statistical physics which does not exceed the background usually taught to students early in their university courses. However, since it finally reaches an advanced level, we have tried to render it as self-contained as possible so that it remains accessible even to an unexperienced reader. Furthermore, the emphasis has been put on a pedagogical level rather than on a technical level. In this spirit, whenever possible, models which are simplified, but which contain the featu...

  14. Decontamination of body surface

    International Nuclear Information System (INIS)

    Harase, Chieko.

    1989-01-01

    There are two important points for an effective application of decontamination procedures. One is the organizing method of responsible decontamination teams. The team should be directed by medical doctor with the knowledge of decontamination of radionuclides. The other point is the place of application of the decontamination. Hospitals and clinics, especially with a department of nuclear medicine, or specialized units such as an emergency medical center are preferable. Before decontamination procedures are initiated, adequate monitoring of the body surface should be undertaken by a competent person in order to demarcate the areas which are contaminated. There are fundamental principles which are applicable to all decontamination procedures. (1) Precautions must always be taken to prevent further spread of contamination during decontamination operations. (2) Mild decontamination methods should be tried before resorting to treatment which can damage the body surface. The specific feature of each contamination varies widely in radionuclides involved, place and area of the contamination, condition of the contaminated skin such as whether the skin is wounded or not, and others. Soap and water are usually good detergents in most cases. If they fail, orange oil cream (SUPERDECONCREAM, available from Tokyo Engineering Co.) specially prepared for decontamination of radionuclides of most fission and corrosion products may be used. Contaminated hair should be washed several times with an efficient shampoo. (author)

  15. Pose Space Surface Manipulation

    Directory of Open Access Journals (Sweden)

    Yusuke Yoshiyasu

    2012-01-01

    Full Text Available Example-based mesh deformation techniques produce natural and realistic shapes by learning the space of deformations from examples. However, skeleton-based methods cannot manipulate a global mesh structure naturally, whereas the mesh-based approaches based on a translational control do not allow the user to edit a local mesh structure intuitively. This paper presents an example-driven mesh editing framework that achieves both global and local pose manipulations. The proposed system is built with a surface deformation method based on a two-step linear optimization technique and achieves direct manipulations of a model surface using translational and rotational controls. With the translational control, the user can create a model in natural poses easily. The rotational control can adjust the local pose intuitively by bending and twisting. We encode example deformations with a rotation-invariant mesh representation which handles large rotations in examples. To incorporate example deformations, we infer a pose from the handle translations/rotations and perform pose space interpolation, thereby avoiding involved nonlinear optimization. With the two-step linear approach combined with the proposed multiresolution deformation method, we can edit models at interactive rates without losing important deformation effects such as muscle bulging.

  16. Smooth surfaces from bilinear patches: Discrete affine minimal surfaces

    KAUST Repository

    Käferböck, Florian

    2013-06-01

    Motivated by applications in freeform architecture, we study surfaces which are composed of smoothly joined bilinear patches. These surfaces turn out to be discrete versions of negatively curved affine minimal surfaces and share many properties with their classical smooth counterparts. We present computational design approaches and study special cases which should be interesting for the architectural application. 2013 Elsevier B.V.

  17. Test surfaces useful for calibration of surface profilometers

    Science.gov (United States)

    Yashchuk, Valeriy V; McKinney, Wayne R; Takacs, Peter Z

    2013-12-31

    The present invention provides for test surfaces and methods for calibration of surface profilometers, including interferometric and atomic force microscopes. Calibration is performed using a specially designed test surface, or the Binary Pseudo-random (BPR) grating (array). Utilizing the BPR grating (array) to measure the power spectral density (PSD) spectrum, the profilometer is calibrated by determining the instrumental modulation transfer.

  18. Femtosecond laser-induced surface wettability modification of polystyrene surface

    Science.gov (United States)

    Wang, Bing; Wang, XinCai; Zheng, HongYu; Lam, YeeCheong

    2016-12-01

    In this paper, we demonstrated a simple method to create either a hydrophilic or hydrophobic surface. With femtosecond laser irradiation at different laser parameters, the water contact angle (WCA) on polystyrene's surface can be modified to either 12.7° or 156.2° from its original WCA of 88.2°. With properly spaced micro-pits created, the surface became hydrophilic probably due to the spread of the water droplets into the micro-pits. While with properly spaced micro-grooves created, the surface became rough and more hydrophobic. We investigated the effect of laser parameters on WCAs and analyzed the laser-treated surface roughness, profiles and chemical bonds by surface profilometer, scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). For the laser-treated surface with low roughness, the polar (such as C—O, C=O, and O—C=O bonds) and non-polar (such as C—C or C—H bonds) groups were found to be responsible for the wettability changes. While for a rough surface, the surface roughness or the surface topography structure played a more significant role in the changes of the surface WCA. The mechanisms involved in the laser surface wettability modification process were discussed.

  19. Theory of quasiparticle surface states in semiconductor surfaces

    International Nuclear Information System (INIS)

    Hybertsen, M.S.; Louie, S.G.

    1988-01-01

    A first-principles theory of the quasiparticle surface-state energies on semiconductor surfaces is developed. The surface properties are calculated using a repeated-slab geometry. Many-body effects due to the electron-electron interaction are represented by the electron self-energy operator including the full surface Green's function and local fields and dynamical screening effects in the Coulomb interaction. Calculated surface-state energies for the prototypical Si(111):As and Ge(111):As surfaces are presented. The calculated energies and dispersions for the occupied surface states (resonances) are in excellent agreement with recent angle-resolved photoemission data. Predictions are made for the position of empty surface states on both surfaces which may be experimentally accessible. The resulting surface state gap at Gamma-bar for Si(111):As agrees with recent scanning-tunneling-spectroscopy measurements. Comparison of the present results to eigenvalues from the local-density-functional calculation reveals substantial corrections for the gaps between empty and occupied surface states. This correction is found to depend on the character of the surface states involved

  20. On-surface synthesis on a bulk insulator surface

    Science.gov (United States)

    Richter, Antje; Floris, Andrea; Bechstein, Ralf; Kantorovich, Lev; Kühnle, Angelika

    2018-04-01

    On-surface synthesis has rapidly emerged as a most promising approach to prepare functional molecular structures directly on a support surface. Compared to solution synthesis, performing chemical reactions on a surface offers several exciting new options: due to the absence of a solvent, reactions can be envisioned that are otherwise not feasible due to the insolubility of the reaction product. Perhaps even more important, the confinement to a two-dimensional surface might enable reaction pathways that are not accessible otherwise. Consequently, on-surface synthesis has attracted great attention in the last decade, with an impressive number of classical reactions transferred to a surface as well as new reactions demonstrated that have no classical analogue. So far, the majority of the work has been carried out on conducting surfaces. However, when aiming for electronic decoupling of the resulting structures, e.g. for the use in future molecular electronic devices, non-conducting surfaces are highly desired. Here, we review the current status of on-surface reactions demonstrated on the (10.4) surface of the bulk insulator calcite. Besides thermally induced C-C coupling of halogen-substituted aryls, photochemically induced [2  +  2] cycloaddition has been proven possible on this surface. Moreover, experimental evidence exists for coupling of terminal alkynes as well as diacetylene polymerization. While imaging of the resulting structures with dynamic atomic force microscopy provides a direct means of reaction verification, the detailed reaction pathway often remains unclear. Especially in cases where the presence of metal atoms is known to catalyze the corresponding solution chemistry reaction (e.g. in the case of the Ullmann reaction), disclosing the precise reaction pathway is of importance to understand and generalize on-surface reactivity on a bulk insulator surface. To this end, density-functional theory calculations have proven to provide atomic

  1. GEWEX Surface Radiation Budget (SRB)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NASA/GEWEX Surface Radiation Budget (SRB) Release-3.0 data sets contains global 3-hourly, daily, monthly/3-hourly, and monthly averages of surface and top-of...

  2. Thermochemical surface engineering of steels

    DEFF Research Database (Denmark)

    Thermochemical Surface Engineering of Steels provides a comprehensive scientific overview of the principles and different techniques involved in thermochemical surface engineering, including thermodynamics, kinetics principles, process technologies and techniques for enhanced performance of steels...

  3. Surface properties of beached plastics.

    Science.gov (United States)

    Fotopoulou, Kalliopi N; Karapanagioti, Hrissi K

    2015-07-01

    Studying plastic characteristics in the marine environment is important to better understand interaction between plastics and the environment. In the present study, high-density polyethylene (HDPE), polyethylene terephalate (PET), and polyvinyl chloride (PVC) samples were collected from the coastal environment in order to study their surface properties. Surface properties such as surface functional groups, surface topography, point of zero charge, and color change are important factors that change during degradation. Eroded HDPE demonstrated an altered surface topography and color and new functional groups. Eroded PET surface was uneven, yellow, and occasionally, colonized by microbes. A decrease in Fourier transform infrared (FTIR) peaks was observed for eroded PET suggesting that degradation had occurred. For eroded PVC, its surface became more lamellar and a new FTIR peak was observed. These surface properties were obtained due to degradation and could be used to explain the interaction between plastics, microbes, and pollutants.

  4. Solid surfaces : some theoretical aspects

    International Nuclear Information System (INIS)

    Das, M.P.

    1978-01-01

    An appraisal of the current situation concerning some of the theoretical aspects of solid surfaces is presented. First of all the characterization of the surfaces that involves the surface geometry and atomic composition for both the clean and adsorbed surfaces is discussed. Under this, the methods for determining the surface structure (such as low energy electron diffraction, field electron and field ion microscopy, photo emission spectroscopy and atomic scattering) and methods for determining the surface composition by the Auger electron spectroscopy are outlined. In the second part, emphasis is on the electronic structure of the clean and adsorbed surfaces. The measurements of ultra-violet and X-ray photo electron spectra are shown to yield the information about the surface electronic structure. In this context the many body effects such as, shake-up and relaxation energy etc. are discussed. Finally the status of the theory in relation to the experiments on angular resolved and polarization dependent photo emission are presented. (auth.)

  5. Classical strings and minimal surfaces

    International Nuclear Information System (INIS)

    Urbantke, H.

    1986-01-01

    Real Lorentzian forms of some complex or complexified Euclidean minimal surfaces are obtained as an application of H.A. Schwarz' solution to the initial value problem or a search for surfaces admitting a group of Poincare transformations. (Author)

  6. Computer representation of molecular surfaces

    International Nuclear Information System (INIS)

    Max, N.L.

    1981-01-01

    This review article surveys recent work on computer representation of molecular surfaces. Several different algorithms are discussed for producing vector or raster drawings of space-filling models formed as the union of spheres. Other smoother surfaces are also considered

  7. Solvay Conference on Surface Science

    CERN Document Server

    1988-01-01

    The articles collected in this volume give a broad overview of the current state of surface science. Pioneers in the field and researchers met together at this Solvay Conference to discuss important new developments in surface science, with an emphasis on the common area between solid state physics and physical chemistry. The contributions deal with the following subjects: structure of surfaces, surface science and catalysis, two-dimensional physics and phase transitions, scanning tunneling microscopy, surface scattering and surface dynamics, chemical reactions at surfaces, solid-solid interfaces and superlattices, and surface studies with synchrotron radiation. On each of these subjects an introductory review talk and a number of short research contributions are followed by extensive discussions, which appear in full in the text. This nineteenth Solvay Conference commemorates the 75th anniversary of the Solvay Institutes.

  8. Emerging trends in surface metrology

    DEFF Research Database (Denmark)

    Lonardo, P.M.; Lucca, D.A.; De Chiffre, Leonardo

    2002-01-01

    Recent advancements and some emerging trends in the methods and instruments used for surface and near surface characterisation are presented, considering the measurement of both topography and physical properties. In particular, surfaces that present difficulties in measurement or require new...... procedures are considered, with emphasis on measurements approaching the nanometre scale. Examples of new instruments and promising innovations for roughness measurement and surface integrity characterisation are presented. The new needs for tolerancing, traceability and calibration are also addressed....

  9. Surface Waves on Metamaterials Interfaces

    DEFF Research Database (Denmark)

    Takayama, Osamu; Shkondin, Evgeniy; Panah, Mohammad Esmail Aryaee

    2016-01-01

    We analyze surface electromagnetic waves supported at the interface between isotropic medium and effective anisotropic material that can be realized by alternating conductive and dielectrics layers. This configuration can host various types of surface waves and therefore can serve as a rich...... platform for applications of surface photonics. Most of these surface waves are directional and as such their propagation can be effectively controlled by changing wavelength or material parameters tuning....

  10. Flow over riblet curved surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, J B R; Freire, A P Silva, E-mail: atila@mecanica.ufrj.br [Mechanical Engineering Program, Federal University of Rio de Janeiro (COPPE/UFRJ), C.P. 68503, 21.941-972, Rio de Janeiro, RJ (Brazil)

    2011-12-22

    The present work studies the mechanics of turbulent drag reduction over curved surfaces by riblets. The effects of surface modification on flow separation over steep and smooth curved surfaces are investigated. Four types of two-dimensional surfaces are studied based on the morphometric parameters that describe the body of a blue whale. Local measurements of mean velocity and turbulence profiles are obtained through laser Doppler anemometry (LDA) and particle image velocimetry (PIV).

  11. Atomic beams probe surface vibrations

    International Nuclear Information System (INIS)

    Robinson, A.L.

    1982-01-01

    In the last two years, surface scientist have begun trying to obtain the vibrational frequencies of surface atoms in both insulating and metallic crystals from beams of helium atoms. It is the inelastic scattering that researchers use to probe surface vibrations. Inelastic atomic beam scattering has only been used to obtain vibrational frequency spectra from clean surfaces. Several experiments using helium beams are cited. (SC)

  12. Reusable Surface Insulation

    Science.gov (United States)

    1997-01-01

    Advanced Flexible Reusable Surface Insulation, developed by Ames Research Center, protects the Space Shuttle from the searing heat that engulfs it on reentry into the Earth's atmosphere. Initially integrated into the Space Shuttle by Rockwell International, production was transferred to Hi-Temp Insulation Inc. in 1974. Over the years, Hi-Temp has created many new technologies to meet the requirements of the Space Shuttle program. This expertise is also used commercially, including insulation blankets to cover aircrafts parts, fire barrier material to protect aircraft engine cowlings and aircraft rescue fire fighter suits. A Fire Protection Division has also been established, offering the first suit designed exclusively by and for aircraft rescue fire fighters. Hi-Temp is a supplier to the Los Angeles City Fire Department as well as other major U.S. civil and military fire departments.

  13. Surface Temperature Data Analysis

    Science.gov (United States)

    Hansen, James; Ruedy, Reto

    2012-01-01

    Small global mean temperature changes may have significant to disastrous consequences for the Earth's climate if they persist for an extended period. Obtaining global means from local weather reports is hampered by the uneven spatial distribution of the reliably reporting weather stations. Methods had to be developed that minimize as far as possible the impact of that situation. This software is a method of combining temperature data of individual stations to obtain a global mean trend, overcoming/estimating the uncertainty introduced by the spatial and temporal gaps in the available data. Useful estimates were obtained by the introduction of a special grid, subdividing the Earth's surface into 8,000 equal-area boxes, using the existing data to create virtual stations at the center of each of these boxes, and combining temperature anomalies (after assessing the radius of high correlation) rather than temperatures.

  14. Surface enhanced thermo lithography

    KAUST Repository

    Coluccio, Maria Laura

    2017-01-13

    We used electroless deposition to fabricate clusters of silver nanoparticles (NPs) on a silicon substrate. These clusters are plasmonics devices that induce giant electromagnetic (EM) field increments. When those EM field are absorbed by the metal NPs clusters generate, in turn, severe temperature increases. Here, we used the laser radiation of a conventional Raman set-up to transfer geometrical patterns from a template of metal NPs clusters into a layer of thermo sensitive Polyphthalaldehyde (PPA) polymer. Temperature profile on the devices depends on specific arrangements of silver nanoparticles. In plane temperature variations may be controlled with (i) high nano-meter spatial precision and (ii) single Kelvin temperature resolution on varying the shape, size and spacing of metal nanostructures. This scheme can be used to generate strongly localized heat amplifications for applications in nanotechnology, surface enhanced thermo-lithography (SETL), biology and medicine (for space resolved cell ablation and treatment), nano-chemistry.

  15. Bacterial surface adaptation

    Science.gov (United States)

    Utada, Andrew

    2014-03-01

    Biofilms are structured multi-cellular communities that are fundamental to the biology and ecology of bacteria. Parasitic bacterial biofilms can cause lethal infections and biofouling, but commensal bacterial biofilms, such as those found in the gut, can break down otherwise indigestible plant polysaccharides and allow us to enjoy vegetables. The first step in biofilm formation, adaptation to life on a surface, requires a working knowledge of low Reynolds number fluid physics, and the coordination of biochemical signaling, polysaccharide production, and molecular motility motors. These crucial early stages of biofilm formation are at present poorly understood. By adapting methods from soft matter physics, we dissect bacterial social behavior at the single cell level for several prototypical bacterial species, including Pseudomonas aeruginosa and Vibrio cholerae.

  16. Nonlinear surface Alfven waves

    International Nuclear Information System (INIS)

    Cramer, N.F.

    1991-01-01

    The problem of nonlinear surface Alfven waves propagating on an interface between a plasma and a vacuum is discussed, with dispersion provided by the finite-frequency effect, i.e. the finite ratio of the frequency to the ion-cyclotron frequency. A set of simplified nonlinear wave equations is derived using the method of stretched co-ordinates, and another approach uses the generation of a second-harmonic wave and its interaction with the first harmonic to obtain a nonlinear dispersion relation. A nonlinear Schroedinger equation is then derived, and soliton solutions found that propagate as solitary pulses in directions close to parallel and antiparallel to the background magnetic field. (author)

  17. Measurement of complex surfaces

    International Nuclear Information System (INIS)

    Brown, G.M.

    1993-05-01

    Several of the components used in coil fabrication involve complex surfaces and dimensions that are not well suited to measurements using conventional dimensional measuring equipment. Some relatively simple techniques that are in use in the SSCL Magnet Systems Division (MSD) for incoming inspection will be described, with discussion of their suitability for specific applications. Components that are submitted for MSD Quality Assurance (QA) dimensional inspection may be divided into two distinct categories; the first category involves components for which there is an approved drawing and for which all nominal dimensions are known; the second category involves parts for which 'reverse engineering' is required, the part is available but there are no available drawings or dimensions. This second category typically occurs during development of coil end parts and coil turn filler parts where it is necessary to manually shape the part and then measure it to develop the information required to prepare a drawing for the part

  18. Surface enhanced thermo lithography

    KAUST Repository

    Coluccio, Maria Laura; Alabastri, Alessandro; Bonanni, Simon; Majewska, Roksana; Dattoli, Elisabetta; Barberio, Marianna; Candeloro, Patrizio; Perozziello, Gerardo; Mollace, Vincenzo; Di Fabrizio, Enzo M.; Gentile, Francesco

    2017-01-01

    We used electroless deposition to fabricate clusters of silver nanoparticles (NPs) on a silicon substrate. These clusters are plasmonics devices that induce giant electromagnetic (EM) field increments. When those EM field are absorbed by the metal NPs clusters generate, in turn, severe temperature increases. Here, we used the laser radiation of a conventional Raman set-up to transfer geometrical patterns from a template of metal NPs clusters into a layer of thermo sensitive Polyphthalaldehyde (PPA) polymer. Temperature profile on the devices depends on specific arrangements of silver nanoparticles. In plane temperature variations may be controlled with (i) high nano-meter spatial precision and (ii) single Kelvin temperature resolution on varying the shape, size and spacing of metal nanostructures. This scheme can be used to generate strongly localized heat amplifications for applications in nanotechnology, surface enhanced thermo-lithography (SETL), biology and medicine (for space resolved cell ablation and treatment), nano-chemistry.

  19. Positron annihilation near fractal surfaces

    International Nuclear Information System (INIS)

    Lung, C.W.; Deng, K.M.; Xiong, L.Y.

    1991-07-01

    A model for positron annihilation in the sub-surface region near a fractal surface is proposed. It is found that the power law relationship between the mean positron implantation depth and incident positron energy can be used to measure the fractal dimension of the fractal surface in materials. (author). 10 refs, 2 figs

  20. Surface mobilities on solid materials

    International Nuclear Information System (INIS)

    Binh, V.T.

    1983-01-01

    This book constitutes the proceedings of the NATO Advanced Study Institute on Surface Mobilities on Solid Materials held in France in 1981. The goal of the two-week meeting was to review up-to-date knowledge on surface diffusion, both theoretical and experimental, and to highlight those areas in which much more knowledge needs to be accumulated. Topics include theoretical aspects of surface diffusion (e.g., microscopic theories of D at zero coverage; statistical mechanical models and surface diffusion); surface diffusion at the atomic level (e.g., FIM studies of surface migration of single adatoms and diatomic clusters; field emission studies of surface diffusion of adsorbates); foreign adsorbate mass transport; self-diffusion mass transport (e.g., different driving forces for the matter transport along surfaces; measurements of the morphological evolution of tips); the role of surface diffusion in some fundamental and applied sciences (e.g. adatomadatom pair interactions and adlayer superstructure formation; surface mobility in chemical reactions and catalysis); and recent works on surface diffusion (e.g., preliminary results on surface self-diffusion measurements on nickel and chromium tips)

  1. Alternative model of random surfaces

    International Nuclear Information System (INIS)

    Ambartzumian, R.V.; Sukiasian, G.S.; Savvidy, G.K.; Savvidy, K.G.

    1992-01-01

    We analyse models of triangulated random surfaces and demand that geometrically nearby configurations of these surfaces must have close actions. The inclusion of this principle drives us to suggest a new action, which is a modified Steiner functional. General arguments, based on the Minkowski inequality, shows that the maximal distribution to the partition function comes from surfaces close to the sphere. (orig.)

  2. Congruences of totally geodesic surfaces

    International Nuclear Information System (INIS)

    Plebanski, J.F.; Rozga, K.

    1989-01-01

    A general theory of congruences of totally geodesic surfaces is presented. In particular their classification, based on the properties of induced affine connections, is provided. In the four-dimensional case canonical forms of the metric tensor admitting congruences of two-dimensional totally geodesic surfaces of rank one are given. Finally, congruences of two-dimensional extremal surfaces are studied. (author)

  3. The surface energy of metals

    DEFF Research Database (Denmark)

    Vitos, Levente; Ruban, Andrei; Skriver, Hans Lomholt

    1998-01-01

    We have used density functional theory to establish a database of surface energies for low index surfaces of 60 metals in the periodic table. The data may be used as a consistent starting point for models of surface science phenomena. The accuracy of the database is established in a comparison...

  4. Surface Effects in Magnetic Nanoparticles

    CERN Document Server

    Fiorani, Dino

    2005-01-01

    This volume is a collection of articles on different approaches to the investigation of surface effects on nanosized magnetic materials, with special emphasis on magnetic nanoparticles. The book aims to provide an overview of progress in the understanding of surface properties and surface driven effects in magnetic nanoparticles through recent results of different modeling, simulation, and experimental investigations.

  5. The surface learned from nature

    Science.gov (United States)

    Lim, H.; Kim, W. D.

    2010-07-01

    In this work, I would like to introduce the emerging surface of nature. The surface in nature, has the multi and optimized function with well organized structure. There are so many examples that we learn and apply to technology. First example is self-cleaning surface. Some plants (such as lotus leaf, taro leaf) and the wings of many large-winged insects (such as moth, butterfly, dragonfly) remain their surface clean in the very dirty environment. This self cleaning effect is accomplished by the superhydrophobic surfaces which exhibit the water contact angle of more than 150° with low sliding angle. Generally, the superhydrophobic surface is made up the two factors. One is the surface composition having the low surface tension energy. The other is the surface morphology of hierarchical structure of micro and nano size. Because almost nature surface have the hierarchical structures range from macro to nano size, their topography strength their function to adjust the life in nature environment. The other example is the surface to use for drag reduction. The skin friction drag causes eruptions of air or water resulting in greater drag as the speed is increased. This drag requires more energy to overcome. The shark skin having the fine sharp-edged grooves about 0.1 mm wide known riblet reduces in skin friction drag by being far away the vortex. Among a lot of fuctional surface, the most exciting surface the back of stenocara a kind of desert beetles. Stenocara use the micrometre-sized patterns of hydrophobic, wax-coated and hydrophilic, non-waxy regions on their backs to capture water from fog. This fog-collecting structure improves the water collection of fog-capture film, condenser, engine, and future building. Here, the efforts to realize these emerging functional surfaces in nature on technology are reported with the fabrication method and their properties, especially for the control of surface wettability.

  6. Enhanced photochemistry on metal surfaces

    International Nuclear Information System (INIS)

    Goncher, G.M.; Parsons, C.A.; Harris, C.B.

    1984-01-01

    Due to the fast relaxation of molecular excited states in the vicinity of a metal or semiconductor surface, few observations of surface photochemistry have been reported. The following work concerns the surface-enhanced photo-reactions of a variety of physisorbed molecules on roughened Ag surfaces. In summary, photodecomposition leads to a graphitic surface carbon product which is monitored via surface-enhanced Raman scattering. In most cases an initial two-photon molecular absorption step followed by further absorption and fragmentation is thought to occur. Enhancement of the incident fields occurs through roughness-mediated surface plasmon resonances. This mechanism provides the amplified electromagnetic surface fields responsible for the observed photodecomposition. The photodecomposition experiments are performed under ultra-high vacuum. Surface characterization of the roughened surfaces was done by Scanning Electron Microscopy (SEM), and electron-stimulated emission. The SEM revealed morphology on the order of 300-400 A. This size of roughness feature, when modelled as isolated spheres should exhibit the well-known Mie resonances for light of the correct wavelengths. For protrusions existing on a surface these Mie resonances can be thought of as a coupling of the light with the surface plasmon. Experimental verification of these resonances was provided by the electron-stimulated light emission results. These showed that a polished Ag surface emitted only the expected transition radiation at the frequency of the Ag bulk plasmon. Upon roughening, however, a broad range of lower frequencies extending well into the visible are seen from electron irradiation of the surface. Large enhancements are expected for those frequencies which are able to couple into the surface modes

  7. Water on a Hydrophobic surface

    Science.gov (United States)

    Scruggs, Ryan; Zhu, Mengjue; Poynor, Adele

    2012-02-01

    Hydrophobicity, meaning literally fear of water, is exhibited on the surfaces of non-stick cooking pans and water resistant clothing, on the leaves of the lotus plan, or even during the protein folding process in our bodies. Hydrophobicity is directly measured by determining a contact angle between water and an objects surface. Associated with a hydrophobic surface is the depletion layer, a low density region approximately 0.2 nm thick. We study this region by comparing data found in lab using surface plasmon resonance techniques to theoretical calculations. Experiments use gold slides coated in ODT and Mercapto solutions to model both hydrophobic and hydrophilic surfaces respectively.

  8. Dual Orlicz geominimal surface area

    Directory of Open Access Journals (Sweden)

    Tongyi Ma

    2016-02-01

    Full Text Available Abstract The L p $L_{p}$ -geominimal surface area was introduced by Lutwak in 1996, which extended the important concept of the geominimal surface area. Recently, Wang and Qi defined the p-dual geominimal surface area, which belongs to the dual Brunn-Minkowski theory. In this paper, based on the concept of the dual Orlicz mixed volume, we extend the dual geominimal surface area to the Orlicz version and give its properties. In addition, the isoperimetric inequality, a Blaschke-Santaló type inequality, and the monotonicity inequality for the dual Orlicz geominimal surface areas are established.

  9. Surface tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Takizuka, Tomonori; Kurita, Gen-ichi; Azumi, Masafumi; Takeda, Tatsuoki

    1985-10-01

    Surface tearing modes in tokamaks are studied numerically and analytically. The eigenvalue problem is solved to obtain the growth rate and the mode structure. We investigate in detail dependences of the growth rate of the m/n = 2/1 resistive MHD modes on the safety factor at the plasma surface, current profile, wall position, and resistivity. The surface tearing mode moves the plasma surface even when the wall is close to the surface. The stability diagram for these modes is presented. (author)

  10. Phase diagrams for surface alloys

    DEFF Research Database (Denmark)

    Christensen, Asbjørn; Ruban, Andrei; Stoltze, Per

    1997-01-01

    We discuss surface alloy phases and their stability based on surface phase diagrams constructed from the surface energy as a function of the surface composition. We show that in the simplest cases of pseudomorphic overlayers there are four generic classes of systems, characterized by the sign...... is based on density-functional calculations using the coherent-potential approximation and on effective-medium theory. We give self-consistent density-functional results for the segregation energy and surface mixing energy for all combinations of the transition and noble metals. Finally we discuss...

  11. Surface-stabilized gold nanocatalysts

    Science.gov (United States)

    Dai, Sheng [Knoxville, TN; Yan, Wenfu [Oak Ridge, TN

    2009-12-08

    A surface-stabilized gold nanocatalyst includes a solid support having stabilizing surfaces for supporting gold nanoparticles, and a plurality of gold nanoparticles having an average particle size of less than 8 nm disposed on the stabilizing surfaces. The surface-stabilized gold nanocatalyst provides enhanced stability, such as at high temperature under oxygen containing environments. In one embodiment, the solid support is a multi-layer support comprising at least a first layer having a second layer providing the stabilizing surfaces disposed thereon, the first and second layer being chemically distinct.

  12. Dynamical speckles in watery surfaces

    International Nuclear Information System (INIS)

    Llovera-Gonzalez, J.J.; Moreno-Yeras, A.; Garcia-Diaz, M.; Alvarez-Salgado, Y.

    2009-01-01

    Recovery of watery surfaces with monolayer of surfactant substances is of interest in diverse technological applications. The format ion and study of molecular monolayer deposited in these surfaces require the application of measurements techniques that allow evaluating the recovery grade locally without modifying practically the studied surface. In this paper the preliminary results obtained by the authors it plows exposed applying the technique of dynamic speckle interferometry in watery surfaces and their consideration like to possible resource to measure the grade of local recovery of these surfaces on the it bases that the speckles pattern dog reveal the dynamics of evaporation that takes place in the same ones. (Author)

  13. Laser surface texturing of tool steel: textured surfaces quality evaluation

    Science.gov (United States)

    Šugár, Peter; Šugárová, Jana; Frnčík, Martin

    2016-05-01

    In this experimental investigation the laser surface texturing of tool steel of type 90MnCrV8 has been conducted. The 5-axis highly dynamic laser precision machining centre Lasertec 80 Shape equipped with the nano-second pulsed ytterbium fibre laser and CNC system Siemens 840 D was used. The planar and spherical surfaces first prepared by turning have been textured. The regular array of spherical and ellipsoidal dimples with a different dimensions and different surface density has been created. Laser surface texturing has been realized under different combinations of process parameters: pulse frequency, pulse energy and laser beam scanning speed. The morphological characterization of ablated surfaces has been performed using scanning electron microscopy (SEM) technique. The results show limited possibility of ns pulse fibre laser application to generate different surface structures for tribological modification of metallic materials. These structures were obtained by varying the processing conditions between surface ablation, to surface remelting. In all cases the areas of molten material and re-cast layers were observed on the bottom and walls of the dimples. Beside the influence of laser beam parameters on the machined surface quality during laser machining of regular hemispherical and elipsoidal dimple texture on parabolic and hemispherical surfaces has been studied.

  14. Superhydrophobic surfaces fabricated by surface modification of alumina particles

    Science.gov (United States)

    Richard, Edna; Aruna, S. T.; Basu, Bharathibai J.

    2012-10-01

    The fabrication of superhydrophobic surfaces has attracted intense interest because of their widespread potential applications in various industrial fields. Recently, some attempts have been carried out to prepare superhydrophobic surfaces using metal oxide nanoparticles. In the present work, superhydrophobic surfaces were fabricated with low surface energy material on alumina particles with different sizes. It was found that particle size of alumina is an important factor in achieving stable superhydrophobic surface. It was possible to obtain alumina surface with water contact angle (WCA) of 156° and a sliding angle of Superhydrophobicity of the modified alumina is attributed to the combined effect of the micro-nanostructure and low surface energy of fatty acid on the surface. The surface morphology of the alumina powder and coatings was determined by FESEM. The stability of the coatings was assessed by conducting water immersion test. Effect of heat treatment on WCA of the coating was also studied. The transition of alumina from hydrophilic to superhydrophobic state was explained using Wenzel and Cassie models. The method is shown to have potential application for creating superhydrophobic surface on cotton fabrics.

  15. Wetting of flat gradient surfaces.

    Science.gov (United States)

    Bormashenko, Edward

    2018-04-01

    Gradient, chemically modified, flat surfaces enable directed transport of droplets. Calculation of apparent contact angles inherent for gradient surfaces is challenging even for atomically flat ones. Wetting of gradient, flat solid surfaces is treated within the variational approach, under which the contact line is free to move along the substrate. Transversality conditions of the variational problem give rise to the generalized Young equation valid for gradient solid surfaces. The apparent (equilibrium) contact angle of a droplet, placed on a gradient surface depends on the radius of the contact line and the values of derivatives of interfacial tensions. The linear approximation of the problem is considered. It is demonstrated that the contact angle hysteresis is inevitable on gradient surfaces. Electrowetting of gradient surfaces is discussed. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Polaron-Driven Surface Reconstructions

    Directory of Open Access Journals (Sweden)

    Michele Reticcioli

    2017-09-01

    Full Text Available Geometric and electronic surface reconstructions determine the physical and chemical properties of surfaces and, consequently, their functionality in applications. The reconstruction of a surface minimizes its surface free energy in otherwise thermodynamically unstable situations, typically caused by dangling bonds, lattice stress, or a divergent surface potential, and it is achieved by a cooperative modification of the atomic and electronic structure. Here, we combined first-principles calculations and surface techniques (scanning tunneling microscopy, non-contact atomic force microscopy, scanning tunneling spectroscopy to report that the repulsion between negatively charged polaronic quasiparticles, formed by the interaction between excess electrons and the lattice phonon field, plays a key role in surface reconstructions. As a paradigmatic example, we explain the (1×1 to (1×2 transition in rutile TiO_{2}(110.

  17. Sea surface stability parameters

    International Nuclear Information System (INIS)

    Weber, A.H.; Suich, J.E.

    1978-01-01

    A number of studies dealing with climatology of the Northwest Atlantic Ocean have been published in the last ten years. These published studies have dealt with directly measured meteorological parameters, e.g., wind speed, temperature, etc. This information has been useful because of the increased focus on the near coastal zone where man's activities are increasing in magnitude and scope, e.g., offshore power plants, petroleum production, and the subsequent environmental impacts of these activities. Atmospheric transport of passive or nonpassive material is significantly influenced by the turbulence structure of the atmosphere in the region of the atmosphere-ocean interface. This research entails identification of the suitability of standard atmospheric stability parameters which can be used to determine turbulence structure; the calculation of these parameters for the near-shore and continental shelf regions of the U.S. east coast from Cape Hatteras to Miami, Florida; and the preparation of a climatology of these parameters. In addition, a climatology for average surface stress for the same geographical region is being prepared

  18. Mercury's Densely Cratered Surface

    Science.gov (United States)

    1974-01-01

    Mariner 10 took this picture (FDS 27465) of the densely cratered surface of Mercury when the spacecraft was 18,200 kilometers (8085 miles) from the planet on March 29. The dark line across top of picture is a 'dropout' of a few TV lines of data. At lower left, a portion of a 61 kilometer (38 mile) crater shows a flow front extending across the crater floor and filling more than half of the crater. The smaller, fresh crater at center is about 25 kilometers (15 miles) in diameter. Craters as small as one kilometer (about one-half mile) across are visible in the picture.The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.Image Credit: NASA/JPL/Northwestern University

  19. Evaporation rates and surface profiles on heterogeneous surfaces with mass transfer and surface reaction

    Energy Technology Data Exchange (ETDEWEB)

    Flytzani-Stephanopoulos, M; Schmidt, L D

    1979-01-01

    Simple models incorporating surface reaction and diffusion of volatile products through a boundary layer are developed to calculate effective rates of evaporation and local surface profiles on surfaces having active and inactive regions. The coupling between surface heterogeneities with respect to a particular reaction and external mass transfer may provide a mechanism for the surface rearrangement and metal loss encountered in several catalytic systems of practical interest. Calculated transport rates for the volatilization of platinum in oxidizing environments and the rearrangement of this metal during the ammonia oxidation reaction agree well with published experimental data.

  20. Topographic characterization of glazed surfaces

    International Nuclear Information System (INIS)

    Froeberg, Linda; Hupa, Leena

    2008-01-01

    Detailed characterization of surface microstructure, i.e. phase composition and surface geometry, has become an important criterion of glazed ceramics. Topographic characterization is an important parameter in, e.g. estimating the influence of additional films on the average roughness of a surface. Also, the microscaled and nanoscaled roughnesses correlate with the cleanability and the self-cleaning properties of the surfaces. In this work the surface geometry of several matte glazes were described by topography and roughness as given by whitelight confocal microscopy and atomic force microscopy. Different measuring parameters were compared to justify the usefulness of the techniques in giving a comprehensive description of the surface microstructure. The results suggest that confocal microscopy is well suited for giving reliable topographical parameters for matte surfaces with microscaled crystals in the surfaces. Atomic force microscopy was better suited for smooth surfaces or for describing the local topographic parameters of closely limited areas, e.g. the surroundings of separate crystals in the surface

  1. Topographic characterization of glazed surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Froeberg, Linda [Process Chemistry Centre, Abo Akademi University, FI-20500 Turku (Finland)], E-mail: lfroberg@abo.fi; Hupa, Leena [Process Chemistry Centre, Abo Akademi University, FI-20500 Turku (Finland)

    2008-01-15

    Detailed characterization of surface microstructure, i.e. phase composition and surface geometry, has become an important criterion of glazed ceramics. Topographic characterization is an important parameter in, e.g. estimating the influence of additional films on the average roughness of a surface. Also, the microscaled and nanoscaled roughnesses correlate with the cleanability and the self-cleaning properties of the surfaces. In this work the surface geometry of several matte glazes were described by topography and roughness as given by whitelight confocal microscopy and atomic force microscopy. Different measuring parameters were compared to justify the usefulness of the techniques in giving a comprehensive description of the surface microstructure. The results suggest that confocal microscopy is well suited for giving reliable topographical parameters for matte surfaces with microscaled crystals in the surfaces. Atomic force microscopy was better suited for smooth surfaces or for describing the local topographic parameters of closely limited areas, e.g. the surroundings of separate crystals in the surface.

  2. Surface parameter characterization of surface vibrations in linear chains

    International Nuclear Information System (INIS)

    Majlis, N.; Selzer, S.; Puszkarski, H.; Diep-The-Hung

    1982-12-01

    We consider the vibrations of a linear monatomic chain with a complex surface potential defined by the surface pinning parameter a=Aesup(-i psi). It is found that in the case of a semi-infinite chain a is connected with the surface vibration wave number k=s+it by the exact relations: s=psi, t=lnA. We also show that the solutions found can be regarded as approximate ones (in the limit L>>1) for surface vibrations of a finite chain consisting of L atoms. (author)

  3. The influence of the surface atomic structure on surface diffusion

    International Nuclear Information System (INIS)

    Ghaleb, Dominique

    1984-03-01

    This work represents the first quantitative study of the influence of the surface atomic structure on surface diffusion (in the range: 0.2 Tf up 0.5 Tf; Tf: melting temperature of the substrate). The analysis of our results on a microscopic scale shows low formation and migration energies for adatoms; we can describe the diffusion on surfaces with a very simple model. On (110) surfaces at low temperature the diffusion is controlled by the exchange mechanism; at higher temperature direct jumps of adatoms along the channels contribute also to the diffusion process. (author) [fr

  4. [Influence of different surface treatments on porcelain surface topography].

    Science.gov (United States)

    Tai, Yinxia; Zhu, Xianchun; Sen, Yan; Liu, Chang; Zhang, Xian; Shi, Xueming

    2013-02-01

    To evaluate the influence of different surface treatments on porcelain surface topography. Metal ceramic prostheses in 6 groups were treated according to the different surface treatment methods, and the surface topography was observed through scanning electron microscope (SEM). Group A was the control one (untreated), group B was etched by 9.6% hydrofluoric acid(HF), group C was deglazed by grinding and then etched by 9.6% HF, group D was treated with Nd: YAG laser irradiation(0.75 W) and HF etching, group E was treated with Nd: YAG laser irradiation (1.05 W) and HF etching, and group F was treated with laser irradiation (1.45 W) and HF etching. Surface topography was different in different groups. A lot of inerratic cracks with the shapes of rhombuses and grid, and crater with a shape of circle were observed on the ceramic surface after treatment with energy parameters of 1.05 W Nd: YAG laser irradiation and 9.6% HF etching (group E). Surface topography showed a lot of concaves on the inner wall of the cracks, and the concaves with diameter of 1-5 microm could be observed on the inner wall of the holes, which had a diameter of 20 microm under SEM. The use of Nd: YAG laser irradiation with the energy parameters of 1.05 W and the HF with a concentration of 9.6% can evenly coarsen the porcelain surface, that is an effective surface treatment method.

  5. Surface Energy and Setting Process of Contacting Surfaces

    Directory of Open Access Journals (Sweden)

    M. V. Musokhranov

    2014-01-01

    Full Text Available The paper deals with a challenge in terms of ensuring an accuracy of the relative position of the conjugated surfaces that is to determine a coefficient of friction. To solve it, there is a proposal to use the surface energy, as a tool that influences the contacting parts nature. Presently, energy of the surface layers at best is only stated, but not used in practice.Analysis of the conditions of interaction between two contacting surfaces, such as seizing and setting cannot be explained only from the position of the roughness parameters. It is found that these phenomena are explained by the appearing gripe (setting bridges, which result from the energy of interaction between two or more adjacent surfaces. The emerging phenomenon such as micro welding, i.e. occurring bonds, is caused by the overflow of energy, according to the theory of physics, from the surface with a high level of energy to the surface with the smaller one to balance the system as a whole.The paper shows that through the use of process, controlling the depth of the surface layer and creating a certain structure, the energy level of the material as a whole can be specified. And this will allow us to provide the necessary performance and mechanical properties. It means to create as many gripe bridges as possible to ensure continuous positioning i.e. a fixed connection of the contacting surfaces.It was determined that to increase a value of the friction coefficient, the physical and mechanical properties of the surface layer of the parts material must be taken into account, namely, in the part body accumulate the energy to be consumed for forming the surface.The paper gives recommendations for including the parts of the surface energy in the qualitative indicators of characteristics. This will make a technologist, when routing a process, to choose such operations and modes to provide the designer-specified parameters not only of the accuracy and surface finish, but also of the

  6. Modelling nanostructures with vicinal surfaces

    International Nuclear Information System (INIS)

    Mugarza, A; Schiller, F; Kuntze, J; Cordon, J; Ruiz-Oses, M; Ortega, J E

    2006-01-01

    Vicinal surfaces of the (111) plane of noble metals are characterized by free-electron-like surface states that scatter at one-dimensional step edges, making them ideal model systems to test the electronic properties of periodic lateral nanostructures. Here we use high-resolution, angle-resolved photoemission to analyse the evolution of the surface state on a variety of vicinal surface structures where both the step potential barrier and the superlattice periodicity can vary. A transition in the electron dimensionality is found as we vary the terrace size in single-phase step arrays. In double-phase, periodic faceted surfaces, we observe surface states that characterize each of the phases

  7. Chemical stabilization of graphite surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bistrika, Alexander A.; Lerner, Michael M.

    2018-04-03

    Embodiments of a device, or a component of a device, including a stabilized graphite surface, methods of stabilizing graphite surfaces, and uses for the devices or components are disclosed. The device or component includes a surface comprising graphite, and a plurality of haloaryl ions and/or haloalkyl ions bound to at least a portion of the graphite. The ions may be perhaloaryl ions and/or perhaloalkyl ions. In certain embodiments, the ions are perfluorobenzenesulfonate anions. Embodiments of the device or component including stabilized graphite surfaces may maintain a steady-state oxidation or reduction surface current density after being exposed to continuous oxidation conditions for a period of at least 1-100 hours. The device or component is prepared by exposing a graphite-containing surface to an acidic aqueous solution of the ions under oxidizing conditions. The device or component can be exposed in situ to the solution.

  8. Friction surfaced Stellite6 coatings

    International Nuclear Information System (INIS)

    Rao, K. Prasad; Damodaram, R.; Rafi, H. Khalid; Ram, G.D. Janaki; Reddy, G. Madhusudhan; Nagalakshmi, R.

    2012-01-01

    Solid state Stellite6 coatings were deposited on steel substrate by friction surfacing and compared with Stellite6 cast rod and coatings deposited by gas tungsten arc and plasma transferred arc welding processes. Friction surfaced coatings exhibited finer and uniformly distributed carbides and were characterized by the absence of solidification structure and compositional homogeneity compared to cast rod, gas tungsten arc and plasma transferred coatings. Friction surfaced coating showed relatively higher hardness. X-ray diffraction of samples showed only face centered cubic Co peaks while cold worked coating showed hexagonally close packed Co also. - Highlights: ► Stellite6 used as coating material for friction surfacing. ► Friction surfaced (FS) coatings compared with casting, GTA and PTA processes. ► Finer and uniformly distributed carbides in friction surfaced coatings. ► Absence of melting results compositional homogeneity in FS Stellite6 coatings.

  9. Surface characterization of ceramic materials

    International Nuclear Information System (INIS)

    Somorjai, G.A.; Salmeron, M.

    1976-01-01

    In recent years several techniques have become available to characterize the structure and chemical composition of surfaces of ceramic materials. These techniques utilize electron scattering and scattering of ions from surfaces. Low-energy electron diffraction is used to determine the surface structure, Auger electron spectroscopy and other techniques of electron spectroscopy (ultraviolet and photoelectron spectroscopies) are employed to determine the composition of the surface. In addition the oxidation state of surface atoms may be determined using these techniques. Ion scattering mass spectrometry and secondary ion mass spectrometry are also useful in characterizing surfaces and their reactions. These techniques, their applications and the results of recent studies are discussed. 12 figures, 52 references, 2 tables

  10. Surface diffusion of sorbed radionuclides

    International Nuclear Information System (INIS)

    Berry, J.A.; Bond, K.A.

    1991-01-01

    Surface diffusion has in the past been invoked to explain rates of radionuclide migration which were greater than those predicted. Results were generally open to interpretation but the possible existence of surface diffusion, whereby sorbed radionuclides could potentially migrate at much enhanced rates, necessitated investigation. In this work through-diffusion experiments have shown that although surface diffusion does exist for some nuclides, the magnitude of the phenomenon is not sufficient to affect repository safety assessment modelling. (author)

  11. How old is surface science?

    International Nuclear Information System (INIS)

    Paparazzo, E.

    2004-01-01

    Philosophical and literary testimonies from the Classical World (5th century B.C. to 3rd century A.D.) involving solid surfaces are reviewed. Plato thought the surface to be a real entity, whereas Aristotle considered it to possess an unqualified existence, i.e. not to be a substance, but just an accidental entity. The Old Stoics asserted that surfaces do not possess any physical existence, although the Stoic philosopher Posidonius--apparently the only exception in his school--held them to exist both in thought and reality. While both the Atomists and the Epicureans were very little interested in them, the Sceptic philosopher Sextus Empiricus considered surfaces to be the limits of a body, although he maintained that both the view that they are corporeal or the view that they are incorporeal present unsurmountable difficulties. Among Roman authors, the testimony from Pliny the Elder is mostly concerned with metallic surfaces, chemical change occurring there, and surface treatments used in antiquity. Besides the philosophical motivations, the implications of the testimonies are discussed in the light of surface science. The purely geometrical surface of Plato is found to compare favorably to single-crystal surface, Posidonius' 'corporeal' surface is best likened to an air-oxidized, or otherwise ambient-modified surface, and ancient accounts on mixture are compared to XPS results obtained in adhesion studies of enameled steels. I argue that the long-standing dominance of Aristotle's view from antiquity onwards may have had a part in delaying theoretical speculation into solid surfaces

  12. Nonlinear optical studies of surfaces

    International Nuclear Information System (INIS)

    Shen, Y.R.

    1994-07-01

    The possibly of using nonlinear optical processes for surface studies has attracted increasing attention in recent years. Optical second harmonic generation (SHG) and sum frequency generation (SFG), in particular, have been well accepted as viable surface probes. They have many advantages over the conventional techniques. By nature, they are highly surface-specific and has a submonolayer sensitivity. As coherent optical processes, they are capable of in-situ probing of surfaces in hostile environment as well as applicable to all interfaces accessible by light. With ultrafast pump laser pulses, they can be employed to study surface dynamic processes with a subpicosecond time resolution. These advantages have opened the door to many exciting research opportunities in surface science and technology. This paper gives a brief overview of this fast-growing new area of research. Optical SHG from a surface was first studied theoretically and experimentally in the sixties. Even the submonolayer surface sensitivity of the process was noticed fairly early. The success was, however, limited because of difficulties in controlling the experimental conditions. It was not until the early 1980's that the potential of the process for surface analysis was duly recognized. The first surface study by SHG was actually motivated by the then active search for an understanding of the intriguing surface enhanced Raman scattering (SERS). It had been suspected that the enhancement in SERS mainly came from the local-field enhancement due to local plasmon resonances and pointing rod effect on rough metal surfaces. In our view, Raman scattering is a two-photon process and is therefore a nonlinear optical effect

  13. Spectra of resonance surface photoionization

    Energy Technology Data Exchange (ETDEWEB)

    Antsiferov, V.V.; Smirnov, G.I.; Telegin, G.G. [Budker Nuclear Physics Institute, Novosibirsk (Russian Federation)

    1995-09-01

    The theory of nonactivated electron transfer between atoms interacting reasonantly with coherent radiation and a metal surface is developed. The spectral resonances in photoabsorption and surface photoionization are found to be related to nonlinear interference effects in the interaction between discrete atomic levels and the continuum formed by the quasi-continuous electron spectrum of a normal metal. The asymmetry in the resonance surface photoionization spectrum is shown to have a shape typical of the Fano autoionization resonances. 18 refs.

  14. Planetary Surface-Atmosphere Interactions

    Science.gov (United States)

    Merrison, J. P.; Bak, E.; Finster, K.; Gunnlaugsson, H. P.; Holstein-Rathlou, C.; Knak Jensen, S.; Nørnberg, P.

    2013-09-01

    Planetary bodies having an accessible solid surface and significant atmosphere, such as Earth, Mars, Venus, Titan, share common phenomenology. Specifically wind induced transport of surface materials, subsequent erosion, the generation and transport of solid aerosols which leads both to chemical and electrostatic interaction with the atmosphere. How these processes affect the evolution of the atmosphere and surface will be discussed in the context of general planetology and the latest laboratory studies will be presented.

  15. Wettability of natural superhydrophobic surfaces.

    Science.gov (United States)

    Webb, Hayden K; Crawford, Russell J; Ivanova, Elena P

    2014-08-01

    Since the description of the 'Lotus Effect' by Barthlott and Neinhuis in 1997, the existence of superhydrophobic surfaces in the natural world has become common knowledge. Superhydrophobicity is associated with a number of possible evolutionary benefits that may be bestowed upon an organism, ranging from the ease of dewetting of their surfaces and therefore prevention of encumbrance by water droplets, self-cleaning and removal of particulates and potential pathogens, and even to antimicrobial activity. The superhydrophobic properties of natural surfaces have been attributed to the presence of hierarchical microscale (>1 μm) and nanoscale (typically below 200 nm) structures on the surface, and as a result, the generation of topographical hierarchy is usually considered of high importance in the fabrication of synthetic superhydrophobic surfaces. When one surveys the breadth of data available on naturally existing superhydrophobic surfaces, however, it can be observed that topographical hierarchy is not present on all naturally superhydrophobic surfaces; in fact, the only universal feature of these surfaces is the presence of a sophisticated nanoscale structure. Additionally, several natural surfaces, e.g. those present on rose petals and gecko feet, display high water contact angles and high adhesion of droplets, due to the pinning effect. These surfaces are not truly superhydrophobic, and lack significant degrees of nanoscale roughness. Here, we discuss the phenomena of superhydrophobicity and pseudo-superhydrophobicity in nature, and present an argument that while hierarchical surface roughness may aid in the stability of the superhydrophobic effect, it is nanoscale surface architecture alone that is the true determinant of superhydrophobicity. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Surfaces allowing for fractional statistics

    International Nuclear Information System (INIS)

    Aneziris, Charilaos.

    1992-07-01

    In this paper we give a necessary condition in order for a geometrical surface to allow for Abelian fractional statistics. In particular, we show that such statistics is possible only for two-dimentional oriented surfaces of genus zero, namely the sphere S 2 , the plane R 2 and the cylindrical surface R 1 *S 1 , and in general the connected sum of n planes R 2 -R 2 -R 2 -...-R 2 . (Author)

  17. Surface-Activated Coupling Reactions Confined on a Surface.

    Science.gov (United States)

    Dong, Lei; Liu, Pei Nian; Lin, Nian

    2015-10-20

    Chemical reactions may take place in a pure phase of gas or liquid or at the interface of two phases (gas-solid or liquid-solid). Recently, the emerging field of "surface-confined coupling reactions" has attracted intensive attention. In this process, reactants, intermediates, and products of a coupling reaction are adsorbed on a solid-vacuum or a solid-liquid interface. The solid surface restricts all reaction steps on the interface, in other words, the reaction takes place within a lower-dimensional, for example, two-dimensional, space. Surface atoms that are fixed in the surface and adatoms that move on the surface often activate the surface-confined coupling reactions. The synergy of surface morphology and activity allow some reactions that are inefficient or prohibited in the gas or liquid phase to proceed efficiently when the reactions are confined on a surface. Over the past decade, dozens of well-known "textbook" coupling reactions have been shown to proceed as surface-confined coupling reactions. In most cases, the surface-confined coupling reactions were discovered by trial and error, and the reaction pathways are largely unknown. It is thus highly desirable to unravel the mechanisms, mechanisms of surface activation in particular, of the surface-confined coupling reactions. Because the reactions take place on surfaces, advanced surface science techniques can be applied to study the surface-confined coupling reactions. Among them, scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS) are the two most extensively used experimental tools. The former resolves submolecular structures of individual reactants, intermediates, and products in real space, while the latter monitors the chemical states during the reactions in real time. Combination of the two methods provides unprecedented spatial and temporal information on the reaction pathways. The experimental findings are complemented by theoretical modeling. In particular, density

  18. Antibacterial surface design - Contact kill

    Science.gov (United States)

    Kaur, Rajbir; Liu, Song

    2016-08-01

    Designing antibacterial surfaces has become extremely important to minimize Healthcare Associated Infections which are a major cause of mortality worldwide. A previous biocide-releasing approach is based on leaching of encapsulated biocides such as silver and triclosan which exerts negative impacts on the environment and potentially contributes to the development of bacterial resistance. This drawback of leachable compounds led to the shift of interest towards a more sustainable and environmentally friendly approach: contact-killing surfaces. Biocides that can be bound onto surfaces to give the substrates contact-active antibacterial activity include quaternary ammonium compounds (QACs), quaternary phosphoniums (QPs), carbon nanotubes, antibacterial peptides, and N-chloramines. Among the above, QACs and N-chloramines are the most researched contact-active biocides. We review the engineering of contact-active surfaces using QACs or N-chloramines, the modes of actions as well as the test methods. The charge-density threshold of cationic surfaces for desired antibacterial efficacy and attempts to combine various biocides for the generation of new contact-active surfaces are discussed in detail. Surface positive charge density is identified as a key parameter to define antibacterial efficacy. We expect that this research field will continue to attract more research interest in view of the potential impact of self-disinfective surfaces on healthcare-associated infections, food safety and corrosion/fouling resistance required on industrial surfaces such as oil pipes and ship hulls.

  19. Are Vicinal Metal Surfaces Stable?

    DEFF Research Database (Denmark)

    Frenken, J. W. M.; Stoltze, Per

    1999-01-01

    We use effective medium theory to demonstrate that the energies of many metal surfaces are lowered when these surfaces are replaced by facets with lower-index orientations. This implies that the low-temperature equilibrium shapes of many metal crystals should be heavily faceted. The predicted...... instability of vicinal metal surfaces is at variance with the almost generally observed stability of these surfaces. We argue that the unstable orientations undergo a defaceting transition at relatively low temperatures, driven by the high vibrational entropy of steps....

  20. Entropic Repulsion Between Fluctuating Surfaces

    Science.gov (United States)

    Janke, W.

    The statistical mechanics of fluctuating surfaces plays an important role in a variety of physical systems, ranging from biological membranes to world sheets of strings in theories of fundamental interactions. In many applications it is a good approximation to assume that the surfaces possess no tension. Their statistical properties are then governed by curvature energies only, which allow for gigantic out-of-plane undulations. These fluctuations are the “entropic” origin of long-range repulsive forces in layered surface systems. Theoretical estimates of these forces for simple model surfaces are surveyed and compared with recent Monte Carlo simulations.

  1. Minimal Surfaces for Hitchin Representations

    DEFF Research Database (Denmark)

    Li, Qiongling; Dai, Song

    2018-01-01

    . In this paper, we investigate the properties of immersed minimal surfaces inside symmetric space associated to a subloci of Hitchin component: $q_n$ and $q_{n-1}$ case. First, we show that the pullback metric of the minimal surface dominates a constant multiple of the hyperbolic metric in the same conformal...... class and has a strong rigidity property. Secondly, we show that the immersed minimal surface is never tangential to any flat inside the symmetric space. As a direct corollary, the pullback metric of the minimal surface is always strictly negatively curved. In the end, we find a fully decoupled system...

  2. Radioactive Probes on Ferromagnetic Surfaces

    CERN Multimedia

    2002-01-01

    On the (broad) basis of our studies of nonmagnetic radioactive probe atoms on magnetic surfaces and at interfaces, we propose to investigate the magnetic interaction of magnetic probe atoms with their immediate environment, in particular of rare earth (RE) elements positioned on and in ferromagnetic surfaces. The preparation and analysis of the structural properties of such samples will be performed in the UHV chamber HYDRA at the HMI/Berlin. For the investigations of the magnetic properties of RE atoms on surfaces Perturbed Angular Correlation (PAC) measurements and Mössbauer Spectroscopy (MS) in the UHV chamber ASPIC (Apparatus for Surface Physics and Interfaces at CERN) are proposed.

  3. Coupling between bulk ordering and surface segregation: from alloy surfaces to surface alloys

    International Nuclear Information System (INIS)

    Gallis, Coralie

    1997-01-01

    -The knowledge of the alloy surfaces is of prime interest to understand their catalytic properties. On the one hand, the determination of the stability of the surface alloys depends very strongly on the behaviours of the A c B 1-c alloy surfaces. On the other hand, the knowledge of the kinetics of the formation-dissolution of surface alloys can allow to understand the equilibrium segregation isotherm. We have then studied the relation between the equilibrium surface segregation in an alloy A c B 1-c and the kinetics of dissolution of a few metallic layers of A/B and the inverse deposit. We have used an energetic model derived from the electronic structure (T.I.B.M.) allowing us to study the surface segregation both in the disordered state and in the ordered one. The kinetics of dissolution were studied using the kinetic version of this model (K.T.I.B.M.) consistent with the equilibrium model. To illustrate our study, we have chosen the Cu-Pd system, a model for the formation of surface alloys and for which a great number of studies, both experimental and theoretical, are in progress. We then have shown for the (111) surface of this system that the surface alloys obtained during the dissolution are related to the alloy surfaces observed for the equilibrium segregation. The Cu-Pd system is characteristic of systems which have a weak segregation energy. Then, we have performed an equivalent study for a system with a strong segregation energy. Our choice was directly put on the Pt-Sn system. The surface behaviour, both in equilibrium and during the kinetics of dissolution, is very different from the Cu-Pd case. In particular, we have found pure 2-D surface alloys. Finally, a quenched molecular dynamics study has allowed us to determine the relative stability of various possible surface superstructures. (author) [fr

  4. Surface composition and surface properties of water hyacinth ...

    African Journals Online (AJOL)

    Surface composition and surface properties of water hyacinth ( Eichhornia ... (2/1, v/v) followed by ethanol, using Fourier Transform Infra-red (FT-IR) spectroscopy, ... polar organic solvents and non-polar n-alkane hydrocarbons is discussed.

  5. Investigation of surface roughness on etched glass surfaces

    International Nuclear Information System (INIS)

    Papa, Z.; Budai, J.; Farkas, B.; Toth, Z.

    2011-01-01

    Roughening the surface of solar cells is a common practice within the photovoltaic industry as it reduces reflectance, and thus enhances the performance of devices. In this work the relationship between reflectance characterized by the haze parameter, surface roughness and optical properties was investigated. To achieve this goal, model samples were prepared by hydrofluoric acid etching of glass for various times and measured by optical microscopy, spectroscopic ellipsometry, scanning electron microscopy, and atomic force microscopy. Our investigation showed that the surface reflectance was decreased not only by the roughening of the surface but also by the modification of the depth profile and lowering of the refractive index of the surface domain of the samples.

  6. Surface Modification and Surface - Subsurface Exchange Processes on Europa

    Science.gov (United States)

    Phillips, C. B.; Molaro, J.; Hand, K. P.

    2017-12-01

    The surface of Jupiter's moon Europa is modified by exogenic processes such as sputtering, gardening, radiolysis, sulfur ion implantation, and thermal processing, as well as endogenic processes including tidal shaking, mass wasting, and the effects of subsurface tectonic and perhaps cryovolcanic activity. New materials are created or deposited on the surface (radiolysis, micrometeorite impacts, sulfur ion implantation, cryovolcanic plume deposits), modified in place (thermal segregation, sintering), transported either vertically or horizontally (sputtering, gardening, mass wasting, tectonic and cryovolcanic activity), or lost from Europa completely (sputtering, plumes, larger impacts). Some of these processes vary spatially, as visible in Europa's leading-trailing hemisphere brightness asymmetry. Endogenic geologic processes also vary spatially, depending on terrain type. The surface can be classified into general landform categories that include tectonic features (ridges, bands, cracks); disrupted "chaos-type" terrain (chaos blocks, matrix, domes, pits, spots); and impact craters (simple, complex, multi-ring). The spatial distribution of these terrain types is relatively random, with some differences in apex-antiapex cratering rates and latitudinal variation in chaos vs. tectonic features. In this work, we extrapolate surface processes and rates from the top meter of the surface in conjunction with global estimates of transport and resurfacing rates. We combine near-surface modification with an estimate of surface-subsurface (and vice versa) transport rates for various geologic terrains based on an average of proposed formation mechanisms, and a spatial distribution of each landform type over Europa's surface area. Understanding the rates and mass balance for each of these processes, as well as their spatial and temporal variability, allows us to estimate surface - subsurface exchange rates over the average surface age ( 50myr) of Europa. Quantifying the timescale

  7. Surface correlations of hydrodynamic drag for transitionally rough engineering surfaces

    Science.gov (United States)

    Thakkar, Manan; Busse, Angela; Sandham, Neil

    2017-02-01

    Rough surfaces are usually characterised by a single equivalent sand-grain roughness height scale that typically needs to be determined from laboratory experiments. Recently, this method has been complemented by a direct numerical simulation approach, whereby representative surfaces can be scanned and the roughness effects computed over a range of Reynolds number. This development raises the prospect over the coming years of having enough data for different types of rough surfaces to be able to relate surface characteristics to roughness effects, such as the roughness function that quantifies the downward displacement of the logarithmic law of the wall. In the present contribution, we use simulation data for 17 irregular surfaces at the same friction Reynolds number, for which they are in the transitionally rough regime. All surfaces are scaled to the same physical roughness height. Mean streamwise velocity profiles show a wide range of roughness function values, while the velocity defect profiles show a good collapse. Profile peaks of the turbulent kinetic energy also vary depending on the surface. We then consider which surface properties are important and how new properties can be incorporated into an empirical model, the accuracy of which can then be tested. Optimised models with several roughness parameters are systematically developed for the roughness function and profile peak turbulent kinetic energy. In determining the roughness function, besides the known parameters of solidity (or frontal area ratio) and skewness, it is shown that the streamwise correlation length and the root-mean-square roughness height are also significant. The peak turbulent kinetic energy is determined by the skewness and root-mean-square roughness height, along with the mean forward-facing surface angle and spanwise effective slope. The results suggest feasibility of relating rough-wall flow properties (throughout the range from hydrodynamically smooth to fully rough) to surface

  8. Surface migration in sorption processes

    International Nuclear Information System (INIS)

    Rasmuson, A.; Neretnieks, J.

    1983-03-01

    Diffusion rates of sorbing chemical species in granites and clays are in several experiments within the KBS study, higher than can be explained by pore diffusion only. One possible additional transport mechanism is transport of of sorbed molecules/ions along the intrapore surfaces. As a first step a literature investigation on on solid surfaces has been conducted. A lot of experimental evidence of the mobility of the sorbed molecules has been gathered through the years, particulary for metal surfaces and chemical engineering systems. For clays however, there are only a few articles, and for granites none. Two types of surface migration models have been proposed in the litterature: i) Surface flow as a result of a gradient in spreading pressure. ii) Surface diffusion as a result of a gradient in concentration. The surface flow model has only been applied to gaseous systems. However, it should be equally applicable to liquid systems. The models i) and ii) are conceptually very different. However, the resulting expressions for surface flux are complicated and it will not be an easy task to distinguish between them. There seem to be three ways of discriminating between the transport mechanisms: a) Temperature dependence. b) Concentration dependence. c) Order of magnitude. (Forf)

  9. Wetting of the diamond surface

    International Nuclear Information System (INIS)

    Hansen, J.O.

    1987-01-01

    The surface conditions which lead to a wide variation in the wettability of diamond surfaces have been investigated using macroscopic surfaces to allow for the crystal anisotropy. A wetting balance method of calculating adhesion tension and hence contact angle has been used for diamonds having major faces near the [111] and [110] lattice planes. Three classes of behaviour have been identified. Surface analyses by Rutherford Backscattering of helium ions, X-ray Photoelectron Spectroscopy and Low Energy Electron Diffraction (LEED) have been used to define the role of the oxygen coverage of the surface in the transition I → O → H. Ferric ion has a hydrophilizing effect on the diamond surface, thought to be the consequence of attachment to the hydroxyl groups at the surface by a ligand mechanism. Other transition metal ions did not show this effect. The phenomenon of hydration of the surface, i.e. progressively more hydrophilic behaviour on prolonged exposure to liquid water, has been quantified. Imbibition or water penetration at microcracks are thought unlikely, and a water cluster build-up at hydrophilic sites is thought to be the best explanation. Dynamic studies indicate little dependence of the advancing contact angle on velocity for velocities up to 10 -4 m/s, and slight dependence of the receding contact angle. Hence advancing angles by this technique are similar to equilibrated contact angles found by optical techniques, but the receding angles are lower than found by other non-dynamic measurements

  10. Surface Detection using Round Cut

    DEFF Research Database (Denmark)

    Dahl, Vedrana Andersen; Dahl, Anders Bjorholm; Larsen, Rasmus

    2014-01-01

    similar adaptations for triangle meshes, our method is capable of capturing complex geometries by iteratively refining the surface, where we obtain a high level of robustness by applying explicit mesh processing to intermediate results. Our method uses on-surface data support, but it also exploits data...

  11. Basic Concepts of Surface Physics

    Energy Technology Data Exchange (ETDEWEB)

    Degras, D A

    1974-07-01

    The basic concepts of surface physics are given in this paper which deals mainly with the thermodynamics of metal surfaces. one finds also a short review of vibrational and electronic properties. Written for a Summer School, the text provides numerous references.

  12. Luminescent Surface Quaternized Carbon Dots

    KAUST Repository

    Bourlinos, Athanasios B.; Zbořil, Radek; Petr, Jan; Bakandritsos, Aristides; Krysmann, Marta; Giannelis, Emmanuel P.

    2012-01-01

    Thermal oxidation of a salt precursor made from the acid base combination of tris(hydroxymethyl)aminomethane and betaine hydrochloride results in light-emitting surface quaternized carbon dots that are water-dispersible, display anion exchange properties, and exhibit uniform size/surface charge. © 2011 American Chemical Society.

  13. Luminescent Surface Quaternized Carbon Dots

    KAUST Repository

    Bourlinos, Athanasios B.

    2012-01-10

    Thermal oxidation of a salt precursor made from the acid base combination of tris(hydroxymethyl)aminomethane and betaine hydrochloride results in light-emitting surface quaternized carbon dots that are water-dispersible, display anion exchange properties, and exhibit uniform size/surface charge. © 2011 American Chemical Society.

  14. Fluorescence Imaging Reveals Surface Contamination

    Science.gov (United States)

    Schirato, Richard; Polichar, Raulf

    1992-01-01

    In technique to detect surface contamination, object inspected illuminated by ultraviolet light to make contaminants fluoresce; low-light-level video camera views fluorescence. Image-processing techniques quantify distribution of contaminants. If fluorescence of material expected to contaminate surface is not intense, tagged with low concentration of dye.

  15. It's About Making Surfaces Invisible

    Indian Academy of Sciences (India)

    It's About Making Surfaces Invisible ... light is reflected from the surface between two media. The in- tensity of ... The reflection from each new interface and the combined reflec- .... Let us see the requirements of a material for a good stamp. The.

  16. Surface Organization Influences Bistable Vision

    Science.gov (United States)

    Graf, Erich W.; Adams, Wendy J.

    2008-01-01

    A priority for the visual system is to construct 3-dimensional surfaces from visual primitives. Information is combined across individual cues to form a robust representation of the external world. Here, it is shown that surface completion relying on multiple visual cues influences relative dominance during binocular rivalry. The shape of a…

  17. Computational Complexity of Combinatorial Surfaces

    NARCIS (Netherlands)

    Vegter, Gert; Yap, Chee K.

    1990-01-01

    We investigate the computational problems associated with combinatorial surfaces. Specifically, we present an algorithm (based on the Brahana-Dehn-Heegaard approach) for transforming the polygonal schema of a closed triangulated surface into its canonical form in O(n log n) time, where n is the

  18. A bag with soft surface

    International Nuclear Information System (INIS)

    Il-Tong Cheon.

    1991-02-01

    The MIT bag has a sharply edged surface. It seems to be unnatural. Taking vector mesons into account, we discuss effects of a smooth surface of the bag constructed by superposition of the MIT bags with various radii on the baryon magnetic moments. (author). 9 refs, 2 figs, 2 tabs

  19. Interference effects with surface plasmons

    NARCIS (Netherlands)

    Kuzmin, Nikolay Victorovich

    2008-01-01

    A surface plasmon is a purely two-dimensional electromagnetic excitation bound to the interface between metal and dielectric and quickly decaying away from it. A surface plasmon is able to concentrate light on sub-wavelength scales – a feature that is attractive for nano-photonics and integrated

  20. Work surface for soluble plutonium

    International Nuclear Information System (INIS)

    Silver, G.L.

    2005-01-01

    A three-dimensional work surface for aqueous plutonium is illustrated. It is constructed by means of estimating work as a function of the ambient pH and redox potential in a plutonium solution. The surface is useful for illustrating the chemistry of disproportionation reactions. Work expressions are easier to use than work integrals. (author)

  1. Trapped surfaces in spherical stars

    International Nuclear Information System (INIS)

    Bizon, P.; Malec, E.; O'Murchadha, N.

    1988-01-01

    We give necessary and sufficient conditions for the existence of trapped surfaces in spherically symmetric spacetimes. These conditions show that the formation of trapped surfaces depends on both the degree of concentration and the average flow of the matter. The result can be considered as a partial validation of the cosmic-censorship hypothesis

  2. Radionuclide transfer onto ground surface in surface water flow, 1

    International Nuclear Information System (INIS)

    Mukai, Masayuki; Takebe, Shinichi; Komiya, Tomokazu; Kamiyama, Hideo

    1991-07-01

    Radionuclides migration in ground surface water flow is considered to be one of the important path way in the scenario for environmental migration of radionuclides leaked from low level radioactive waste repository. Simulating the slightly sloped surface on which contaminated solution is flowing downward, testing for radionuclide migration on ground surface had been started. As it's first step, an experiment was carried out under the condition of restricted infiltration in order to elucidate the adsorption behavior of radionuclides onto the loamy soil surface in related with hydraulic conditions. Radionuclides concentration change in effluent solution with time and a concentration distribution of radionuclides adsorbed on the ground surface were obtained from several experimental conditions combining the rate and the duration time of the water flow. The radionuclides concentration in the effluent solution was nearly constant during each experimental period, and was reduced under the condition of lower flow rate. The surface distribution of radionuclides concentration showed two distinctive regions. The one was near the inlet vessel where the concentration was promptly reducing, and the other was following the former where the concentration was nearly constant. The characteristic surface distribution of radionuclides concentration can be explained by a two dimensional diffusion model with a first order adsorption reaction, based on the advection of flow rate distribution in perpendicular direction. (author)

  3. Scanning Surface Potential Microscopy of Spore Adhesion on Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ida [University of Tennessee, Knoxville (UTK); Chung, Eunhyea [Georgia Institute of Technology; Kweon, Hyojin [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Tsouris, Costas [ORNL

    2012-01-01

    The adhesion of spores of Bacillus anthracis - the cause of anthrax and a likely biological threat - to solid surfaces is an important consideration in cleanup after an accidental or deliberate release. However, because of safety concerns, directly studying B. anthracis spores with advanced instrumentation is problematic. As a first step, we are examining the electrostatic potential of Bacillus thuringiensis (Bt), which is a closely related species that is often used as a simulant to study B. anthracis. Scanning surface potential microscopy (SSPM), also known as Kelvin probe force microscopy (KPFM), was used to investigate the influence of relative humidity (RH) on the surface electrostatic potential of Bt that had adhered to silica, mica, or gold substrates. AFM/SSPM side-by-side images were obtained separately in air, at various values of RH, after an aqueous droplet with spores was applied on each surface and allowed to dry before measurements. In the SSPM images, a negative potential on the surface of the spores was observed compared with that of the substrates. The surface potential decreased as the humidity increased. Spores were unable to adhere to a surface with an extremely negative potential, such as mica.

  4. Ion surface collisions on surfaces relevant for fusion devices

    International Nuclear Information System (INIS)

    Rasul, B.; Endstrasser, N.; Zappa, F.; Grill, V.; Scheier, P.; Mark, T.

    2006-01-01

    Full text: One of the great challenges of fusion research is the compatibility of reactor grade plasmas with plasma facing materials coating the inner walls of a fusion reactor. The question of which surface coating should be used is of particular interest for the design of ITER. The impact of energetic plasma particles leads to sputtering of wall material into the plasma. A possible solution for the coating of plasma facing walls would be the use of special carbon surfaces. Investigations of these various surfaces have been started at BESTOF ion-surface collision apparatus. Experiment beam of singly charged molecular ions of hydrocarbon molecules, i.e. C 2 H + 4 , is generated in a Nier-type electron impact ionization source at an electron energy of about 70 eV. In the first double focusing mass spectrometer the ions are mass and energy analyzed and afterwards refocused onto a surface. The secondary reaction products are monitored using a Time Of Flight mass spectrometer. The secondary ion mass spectra are recorded as a function of the collision energy for different projectile ions and different surfaces. A comparison of these spectra show for example distinct changes in the survival probability of the same projectile ion C 2 H + 4 for different surfaces. (author)

  5. Surface electrostatics: theory and computations

    KAUST Repository

    Chatzigeorgiou, G.

    2014-02-05

    The objective of this work is to study the electrostatic response of materials accounting for boundary surfaces with their own (electrostatic) constitutive behaviour. The electric response of materials with (electrostatic) energetic boundary surfaces (surfaces that possess material properties and constitutive structures different from those of the bulk) is formulated in a consistent manner using a variational framework. The forces and moments that appear due to bulk and surface electric fields are also expressed in a consistent manner. The theory is accompanied by numerical examples on porous materials using the finite-element method, where the influence of the surface electric permittivity on the electric displacement, the polarization stress and the Maxwell stress is examined.

  6. Modern techniques of surface science

    CERN Document Server

    Woodruff, D Phil

    2016-01-01

    This fully revised, updated and reorganised third edition provides a thorough introduction to the characterisation techniques used in surface science and nanoscience today. Each chapter brings together and compares the different techniques used to address a particular research question, including how to determine the surface composition, surface structure, surface electronic structure, surface microstructure at different length scales (down to sub-molecular), and the molecular character of adsorbates and their adsorption or reaction properties. Readers will easily understand the relative strengths and limitations of the techniques available to them and, ultimately, will be able to select the most suitable techniques for their own particular research purposes. This is an essential resource for researchers and practitioners performing materials analysis, and for senior undergraduate students looking to gain a clear understanding of the underlying principles and applications of the different characterisation tec...

  7. Fermi surfaces in Kondo insulators

    Science.gov (United States)

    Liu, Hsu; Hartstein, Máté; Wallace, Gregory J.; Davies, Alexander J.; Ciomaga Hatnean, Monica; Johannes, Michelle D.; Shitsevalova, Natalya; Balakrishnan, Geetha; Sebastian, Suchitra E.

    2018-04-01

    We report magnetic quantum oscillations measured using torque magnetisation in the Kondo insulator YbB12 and discuss the potential origin of the underlying Fermi surface. Observed quantum oscillations as well as complementary quantities such as a finite linear specific heat capacity in YbB12 exhibit similarities with the Kondo insulator SmB6, yet also crucial differences. Small heavy Fermi sections are observed in YbB12 with similarities to the neighbouring heavy fermion semimetallic Fermi surface, in contrast to large light Fermi surface sections in SmB6 which are more similar to the conduction electron Fermi surface. A rich spectrum of theoretical models is suggested to explain the origin across different Kondo insulating families of a bulk Fermi surface potentially from novel itinerant quasiparticles that couple to magnetic fields, yet do not couple to weak DC electric fields.

  8. Surface states in photonic crystals

    Directory of Open Access Journals (Sweden)

    Vojtíšek P.

    2013-05-01

    Full Text Available Among many unusual and interesting physical properties of photonic crystals (PhC, in recent years, the propagation of surface electromagnetic waves along dielectric PhC boundaries have attracted considerable attention, also in connection to their possible applications. Such surfaces states, produced with the help of specialized defects on PhC boundaries, similarly to surfaces plasmons, are localized surfaces waves and, as such, can be used in various sensing applications. In this contribution, we present our recent studies on numerical modelling of surface states (SS for all three cases of PhC dimensionality. Simulations of these states were carried out by the use of plane wave expansion (PWE method via the MIT MPB package.

  9. Computational approach to Riemann surfaces

    CERN Document Server

    Klein, Christian

    2011-01-01

    This volume offers a well-structured overview of existent computational approaches to Riemann surfaces and those currently in development. The authors of the contributions represent the groups providing publically available numerical codes in this field. Thus this volume illustrates which software tools are available and how they can be used in practice. In addition examples for solutions to partial differential equations and in surface theory are presented. The intended audience of this book is twofold. It can be used as a textbook for a graduate course in numerics of Riemann surfaces, in which case the standard undergraduate background, i.e., calculus and linear algebra, is required. In particular, no knowledge of the theory of Riemann surfaces is expected; the necessary background in this theory is contained in the Introduction chapter. At the same time, this book is also intended for specialists in geometry and mathematical physics applying the theory of Riemann surfaces in their research. It is the first...

  10. Surface science and heterogeneous catalysis

    International Nuclear Information System (INIS)

    Somorjai, G.A.

    1980-05-01

    The catalytic reactions studied include hydrocarbon conversion over platinum, the transition metal-catalyzed hydrogenation of carbon monoxide, and the photocatalyzed dissociation of water over oxide surfaces. The method of combined surface science and catalytic studies is similar to those used in synthetic organic chemistry. The single-crystal models for the working catalyst are compared with real catalysts by comparing the rates of cyclopropane ring opening on platinum and the hydrogenation of carbon monoxide on rhodium single crystal surface with those on practical commercial catalyst systems. Excellent agreement was obtained for these reactions. This document reviews what was learned about heterogeneous catalysis from these surface science approaches over the past 15 years and present models of the active catalyst surface

  11. Capillary waves with surface viscosity

    Science.gov (United States)

    Shen, Li; Denner, Fabian; Morgan, Neal; van Wachem, Berend; Dini, Daniele

    2017-11-01

    Experiments over the last 50 years have suggested a correlation between the surface (shear) viscosity and the stability of a foam or emulsion. With recent techniques allowing more accurate measurements of the elusive surface viscosity, we examine this link theoretically using small-amplitude capillary waves in the presence of the Marangoni effect and surface viscosity modelled via the Boussinesq-Scriven model. The surface viscosity effect is found to contribute a damping effect on the amplitude of the capillary wave with subtle differences to the effect of the convective-diffusive Marangoni transport. The general wave dispersion is augmented to take into account the Marangoni and surface viscosity effects, and a first-order correction to the critical damping wavelength is derived. The authors acknowledge the financial support of the Shell University Technology Centre for fuels and lubricants.

  12. Physics of Surfaces and Interfaces

    CERN Document Server

    Ibach, Harald

    2006-01-01

    This graduate-level textbook covers the major developments in surface sciences of recent decades, from experimental tricks and basic techniques to the latest experimental methods and theoretical understanding. It is unique in its attempt to treat the physics of surfaces, thin films and interfaces, surface chemistry, thermodynamics, statistical physics and the physics of the solid/electrolyte interface in an integral manner, rather than in separate compartments. The Physics of Surfaces and Interfaces is designed as a handbook for the researcher as well as a study-text for graduate students in physics or chemistry with special interest in the surface sciences, material science, or the nanosciences. The experienced researcher, professional or academic teacher will appreciate the opportunity to share many insights and ideas that have grown out of the author's long experience. Readers will likewise appreciate the wide range of topics treated, each supported by extensive references. Graduate students will benefit f...

  13. Atmosphere-surface interactions over polar oceans and heterogeneous surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Vihma, T.

    1995-12-31

    Processes of interaction between the atmospheric boundary layer and the planetary surface have been studied with special emphasis on polar ocean surfaces: the open ocean, leads, polynyas and sea ice. The local exchange of momentum, heat and moisture has been studied experimentally both in the Weddell Sea and in the Greenland Sea. Exchange processes over heterogeneous surfaces are addressed by modelling studies. Over a homogeneous surface, the local turbulent fluxes can be reasonably well estimated using an iterative flux-profile scheme based on the Monin-Obukhov similarity theory. In the Greenland Sea, the near-surface air temperature and the generally small turbulent fluxes over the open ocean were affected by the sea surface temperature fronts. Over the sea ice cover in the Weddell Sea, the turbulent sensible heat flux was generally downwards, and together with an upward oceanic heat flux through the ice it compensated the heat loss from the surface via long-wave radiation. The wind dominated on time scales of days, while the current became important on longer time scales. The drift dynamics showed apparent spatial differences between the eastern and western regions, as well as between the Antarctic Circumpolar Current and the rest of the Weddell Sea. Inertial motion was present in regions of low ice concentration. The surface heterogeneity, arising e.g. from roughness or temperature distribution, poses a problem for the parameterization of surface exchange processes in large-scale models. In the case of neutral flow over a heterogeneous terrain, an effective roughness length can be used to parameterize the roughness effects

  14. Atmosphere-surface interactions over polar oceans and heterogeneous surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Vihma, T

    1996-12-31

    Processes of interaction between the atmospheric boundary layer and the planetary surface have been studied with special emphasis on polar ocean surfaces: the open ocean, leads, polynyas and sea ice. The local exchange of momentum, heat and moisture has been studied experimentally both in the Weddell Sea and in the Greenland Sea. Exchange processes over heterogeneous surfaces are addressed by modelling studies. Over a homogeneous surface, the local turbulent fluxes can be reasonably well estimated using an iterative flux-profile scheme based on the Monin-Obukhov similarity theory. In the Greenland Sea, the near-surface air temperature and the generally small turbulent fluxes over the open ocean were affected by the sea surface temperature fronts. Over the sea ice cover in the Weddell Sea, the turbulent sensible heat flux was generally downwards, and together with an upward oceanic heat flux through the ice it compensated the heat loss from the surface via long-wave radiation. The wind dominated on time scales of days, while the current became important on longer time scales. The drift dynamics showed apparent spatial differences between the eastern and western regions, as well as between the Antarctic Circumpolar Current and the rest of the Weddell Sea. Inertial motion was present in regions of low ice concentration. The surface heterogeneity, arising e.g. from roughness or temperature distribution, poses a problem for the parameterization of surface exchange processes in large-scale models. In the case of neutral flow over a heterogeneous terrain, an effective roughness length can be used to parameterize the roughness effects

  15. Surface-enhanced chiroptical spectroscopy with superchiral surface waves.

    Science.gov (United States)

    Pellegrini, Giovanni; Finazzi, Marco; Celebrano, Michele; Duò, Lamberto; Biagioni, Paolo

    2018-07-01

    We study the chiroptical properties of one-dimensional photonic crystals supporting superchiral surface waves by introducing a simple formalism based on the Fresnel reflection matrix. We show that the proposed framework provides useful insights on the behavior of all the relevant chiroptical quantities, allowing for a deeper understanding of surface-enhanced chiral sensing platforms based on one-dimensional photonic crystals. Finally, we analyze and discuss the limitations of such platforms as the surface concentration of the target chiral analytes is gradually increased. © 2018 Wiley Periodicals, Inc.

  16. Modification of Surface Energy via Direct Laser Ablative Surface Patterning

    Science.gov (United States)

    Wohl, Christopher J., Jr. (Inventor); Belcher, Marcus A. (Inventor); Connell, John W. (Inventor); Hopkins, John W. (Inventor)

    2015-01-01

    Surface energy of a substrate is changed without the need for any template, mask, or additional coating medium applied to the substrate. At least one beam of energy directly ablates a substrate surface to form a predefined topographical pattern at the surface. Each beam of energy has a width of approximately 25 micrometers and an energy of approximately 1-500 microJoules. Features in the topographical pattern have a width of approximately 1-500 micrometers and a height of approximately 1.4-100 micrometers.

  17. Surface impedance and optimum surface resistance of a superconductor with an imperfect surface

    Science.gov (United States)

    Gurevich, Alex; Kubo, Takayuki

    2017-11-01

    We calculate a low-frequency surface impedance of a dirty, s -wave superconductor with an imperfect surface incorporating either a thin layer with a reduced pairing constant or a thin, proximity-coupled normal layer. Such structures model realistic surfaces of superconducting materials which can contain oxide layers, absorbed impurities, or nonstoichiometric composition. We solved the Usadel equations self-consistently and obtained spatial distributions of the order parameter and the quasiparticle density of states which then were used to calculate a low-frequency surface resistance Rs(T ) and the magnetic penetration depth λ (T ) as functions of temperature in the limit of local London electrodynamics. It is shown that the imperfect surface in a single-band s -wave superconductor results in a nonexponential temperature dependence of Z (T ) at T ≪Tc which can mimic the behavior of multiband or d -wave superconductors. The imperfect surface and the broadening of the gap peaks in the quasiparticle density of states N (ɛ ) in the bulk give rise to a weakly temperature-dependent residual surface resistance. We show that the surface resistance can be optimized and even reduced below its value for an ideal surface by engineering N (ɛ ) at the surface using pair-breaking mechanisms, particularly by incorporating a small density of magnetic impurities or by tuning the thickness and conductivity of the normal layer and its contact resistance. The results of this work address the limit of Rs in superconductors at T ≪Tc , and the ways of engineering the optimal density of states by surface nanostructuring and impurities to reduce losses in superconducting microresonators, thin-film strip lines, and radio-frequency cavities for particle accelerators.

  18. Reconstruction of Kinematic Surfaces from Scattered Data

    DEFF Research Database (Denmark)

    Randrup, Thomas; Pottmann, Helmut; Lee, I.-K.

    1998-01-01

    Given a surface in 3-space or scattered points from a surface, we present algorithms for fitting the data by a surface which can be generated by a one--parameter subgroup of the group of similarities. These surfaces are general cones and cylinders, surfaces of revolution, helical surfaces and spi...

  19. Surface topography and morphology characterization of PIII irradiated silicon surface

    International Nuclear Information System (INIS)

    Sharma, Satinder K.; Barthwal, Sumit

    2008-01-01

    The effect of plasma immersion ion implantation (PIII) treatment on silicon surfaces was investigated by micro-Raman and atomic force microscopy (AFM) technique. The surface damage was given by the implantation of carbon, nitrogen, oxygen and argon ions using an inductively coupled plasma (ICP) source at low pressure. AFM studies show that surface topography of the PIII treated silicon wafers depend on the physical and chemical nature of the implanted species. Micro-Raman spectra indicate that the significant reduction of intensity of Raman peak after PIII treatment. Plasma immersion ion implantation is a non-line-of-sight ion implantation method, which allows 3D treatment of materials. Therefore, PIII based surface modification and plasma immersion ion deposition (PIID) coatings are applied in a wide range of situations.

  20. Molecular tailoring of solid surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Evenson, Simon Alan

    1997-07-01

    The overall performance of a material can be dramatically improved by tailoring its surface at the molecular level. The aim of this project was to develop a universal technique for attaching dendrimers (well-defined, nanoscale, functional polymers) and Jeffamines (high molecular weight polymer chains) to the surface of any shaped solid substrate. This desire for controlled functionalization is ultimately driven by the need to improve material compatibility in various biomedical applications. Atomic force microscopy (AFM) was used initially to study the packing and structure of Langmuir-Blodgett films on surfaces, and subsequently resulted in the first visualization of individual, spherically shaped, nanoscopic polyamidoamine dendrimers. The next goal was to develop a methodology for attaching such macromolecules to inert surfaces. Thin copolymer films were deposited onto solid substrates to produce materials with a fixed concentration of surface anhydride groups. Vapor-phase functionalization reactions were then carried out with trifluorinated amines to confirm the viability of this technique to bond molecules to surfaces. Finally, pulsed plasma polymerization of maleic anhydride took this approach one stage further, by forming well-adhered polymer films containing a predetermined concentration of reactive anhydride groups. Subsequent functionalization reactions led to the secure attachment of dendrimers and Jeffamines at any desired packing density. An alternative route to biocompatibilization used 1,2-ethanedithiol to yield thiolated surfaces containing very high polymeric sulfur : carbon ratios. (author)

  1. Molecular tailoring of solid surfaces

    International Nuclear Information System (INIS)

    Evenson, Simon Alan

    1997-01-01

    The overall performance of a material can be dramatically improved by tailoring its surface at the molecular level. The aim of this project was to develop a universal technique for attaching dendrimers (well-defined, nanoscale, functional polymers) and Jeffamines (high molecular weight polymer chains) to the surface of any shaped solid substrate. This desire for controlled functionalization is ultimately driven by the need to improve material compatibility in various biomedical applications. Atomic force microscopy (AFM) was used initially to study the packing and structure of Langmuir-Blodgett films on surfaces, and subsequently resulted in the first visualization of individual, spherically shaped, nanoscopic polyamidoamine dendrimers. The next goal was to develop a methodology for attaching such macromolecules to inert surfaces. Thin copolymer films were deposited onto solid substrates to produce materials with a fixed concentration of surface anhydride groups. Vapor-phase functionalization reactions were then carried out with trifluorinated amines to confirm the viability of this technique to bond molecules to surfaces. Finally, pulsed plasma polymerization of maleic anhydride took this approach one stage further, by forming well-adhered polymer films containing a predetermined concentration of reactive anhydride groups. Subsequent functionalization reactions led to the secure attachment of dendrimers and Jeffamines at any desired packing density. An alternative route to biocompatibilization used 1,2-ethanedithiol to yield thiolated surfaces containing very high polymeric sulfur : carbon ratios. (author)

  2. Monte Carlo surface flux tallies

    International Nuclear Information System (INIS)

    Favorite, Jeffrey A.

    2010-01-01

    Particle fluxes on surfaces are difficult to calculate with Monte Carlo codes because the score requires a division by the surface-crossing angle cosine, and grazing angles lead to inaccuracies. We revisit the standard practice of dividing by half of a cosine 'cutoff' for particles whose surface-crossing cosines are below the cutoff. The theory behind this approximation is sound, but the application of the theory to all possible situations does not account for two implicit assumptions: (1) the grazing band must be symmetric about 0, and (2) a single linear expansion for the angular flux must be applied in the entire grazing band. These assumptions are violated in common circumstances; for example, for separate in-going and out-going flux tallies on internal surfaces, and for out-going flux tallies on external surfaces. In some situations, dividing by two-thirds of the cosine cutoff is more appropriate. If users were able to control both the cosine cutoff and the substitute value, they could use these parameters to make accurate surface flux tallies. The procedure is demonstrated in a test problem in which Monte Carlo surface fluxes in cosine bins are converted to angular fluxes and compared with the results of a discrete ordinates calculation.

  3. Erosion of surface and near surface disposal facilities

    International Nuclear Information System (INIS)

    1988-06-01

    A literature search was undertaken to identify existing data and analytical procedures regarding the processes of gully erosion. The applicability of the available information to the problems of gully erosion potential at surface and near surface disposal sites is evaluated. It is concluded that the existing knowledge regarding gully erosion is insufficient to develop procedures to ensure the long-term stability of disposal sites. Recommendations for further research are presented. 46 refs

  4. Plastic Deformation of Metal Surfaces

    DEFF Research Database (Denmark)

    Hansen, Niels; Zhang, Xiaodan; Huang, Xiaoxu

    2013-01-01

    of metal components. An optimization of processes and material parameters must be based on a quantification of stress and strain gradients at the surface and in near surface layer where the structural scale can reach few tens of nanometers. For such fine structures it is suggested to quantify structural...... parameters by TEM and EBSD and apply strength-structural relationships established for the bulk metal deformed to high strains. This technique has been applied to steel deformed by high energy shot peening and a calculated stress gradient at or near the surface has been successfully validated by hardness...

  5. Surface analysis the principal techniques

    CERN Document Server

    Vickerman, John C

    2009-01-01

    This completely updated and revised second edition of Surface Analysis: The Principal Techniques, deals with the characterisation and understanding of the outer layers of substrates, how they react, look and function which are all of interest to surface scientists. Within this comprehensive text, experts in each analysis area introduce the theory and practice of the principal techniques that have shown themselves to be effective in both basic research and in applied surface analysis. Examples of analysis are provided to facilitate the understanding of this topic and to show readers how they c

  6. Sound radiation from finite surfaces

    DEFF Research Database (Denmark)

    Brunskog, Jonas

    2013-01-01

    A method to account for the effect of finite size in acoustic power radiation problem of planar surfaces using spatial windowing is developed. Cremer and Heckl presents a very useful formula for the power radiating from a structure using the spatially Fourier transformed velocity, which combined...... with spatially windowing of a plane waves can be used to take into account the finite size. In the present paper, this is developed by means of a radiation impedance for finite surfaces, that is used instead of the radiation impedance for infinite surfaces. In this way, the spatial windowing is included...

  7. Surface defects and chiral algebras

    Energy Technology Data Exchange (ETDEWEB)

    Córdova, Clay [School of Natural Sciences, Institute for Advanced Study,1 Einstein Dr, Princeton, NJ 08540 (United States); Gaiotto, Davide [Perimeter Institute for Theoretical Physics,31 Caroline St N, Waterloo, ON N2L 2Y5 (Canada); Shao, Shu-Heng [School of Natural Sciences, Institute for Advanced Study,1 Einstein Dr, Princeton, NJ 08540 (United States)

    2017-05-26

    We investigate superconformal surface defects in four-dimensional N=2 superconformal theories. Each such defect gives rise to a module of the associated chiral algebra and the surface defect Schur index is the character of this module. Various natural chiral algebra operations such as Drinfeld-Sokolov reduction and spectral flow can be interpreted as constructions involving four-dimensional surface defects. We compute the index of these defects in the free hypermultiplet theory and Argyres-Douglas theories, using both infrared techniques involving BPS states, as well as renormalization group flows onto Higgs branches. In each case we find perfect agreement with the predicted characters.

  8. Differential geometry curves, surfaces, manifolds

    CERN Document Server

    Kohnel, Wolfgang

    2002-01-01

    This carefully written book is an introduction to the beautiful ideas and results of differential geometry. The first half covers the geometry of curves and surfaces, which provide much of the motivation and intuition for the general theory. Special topics that are explored include Frenet frames, ruled surfaces, minimal surfaces and the Gauss-Bonnet theorem. The second part is an introduction to the geometry of general manifolds, with particular emphasis on connections and curvature. The final two chapters are insightful examinations of the special cases of spaces of constant curvature and Einstein manifolds. The text is illustrated with many figures and examples. The prerequisites are undergraduate analysis and linear algebra.

  9. Global Analysis of Minimal Surfaces

    CERN Document Server

    Dierkes, Ulrich; Tromba, Anthony J

    2010-01-01

    Many properties of minimal surfaces are of a global nature, and this is already true for the results treated in the first two volumes of the treatise. Part I of the present book can be viewed as an extension of these results. For instance, the first two chapters deal with existence, regularity and uniqueness theorems for minimal surfaces with partially free boundaries. Here one of the main features is the possibility of 'edge-crawling' along free parts of the boundary. The third chapter deals with a priori estimates for minimal surfaces in higher dimensions and for minimizers of singular integ

  10. Dust Dynamics Near Planetary Surfaces

    Science.gov (United States)

    Colwell, Joshua; Hughes, Anna; Grund, Chris

    Observations of a lunar "horizon glow" by several Surveyor spacecraft in the 1960s opened the study of the dynamics of charged dust particles near planetary surfaces. The surfaces of the Moon and other airless planetary bodies in the solar system (asteroids, and other moons) are directly exposed to the solar wind and ionizing solar ultraviolet radiation, resulting in a time-dependent electric surface potential. Because these same objects are also exposed to bombardment by micrometeoroids, the surfaces are usually characterized by a power-law size distribution of dust that extends to sub-micron-sized particles. Individual particles can acquire a charge different from their surroundings leading to electrostatic levitation. Once levitated, particles may simply return to the surface on nearly ballistic trajectories, escape entirely from the moon or asteroid if the initial velocity is large, or in some cases be stably levitated for extended periods of time. All three outcomes have observable consequences. Furthermore, the behavior of charged dust near the surface has practical implications for planned future manned and unmanned activities on the lunar surface. Charged dust particles also act as sensitive probes of the near-surface plasma environment. Recent numerical modeling of dust levitation and transport show that charged micron-sized dust is likely to accumulate in topographic lows such as craters, providing a mechanism for the creation of dust "ponds" observed on the asteroid 433 Eros. Such deposition can occur when particles are supported by the photoelectron sheath above the dayside and drift over shadowed regions of craters where the surface potential is much smaller. Earlier studies of the lunar horizon glow are consistent with those particles being on simple ballistic trajectories following electrostatic launching from the surface. Smaller particles may be accelerated from the lunar surface to high altitudes consistent with observations of high altitude

  11. Management národních parků: ochrana stavu versus ochrana procesů

    Czech Academy of Sciences Publication Activity Database

    Härtel, Handrij

    2009-01-01

    Roč. 44, Mat. 24 (2009), s. 25-33 ISSN 1212-3323. [Diverzita, dynamika a management lesní vegetace. Praha, 29.11.2008-30.11.2008] Institutional research plan: CEZ:AV0Z60050516 Keywords : IUCN category * national park * spontaneous processes Subject RIV: EF - Botanics

  12. Proces vysokorychlostního čiření - moderní technologie úpravy vody

    Czech Academy of Sciences Publication Activity Database

    Pivokonský, Martin; Polášek, Pavel; Knesl, Bohuslav

    2009-01-01

    Roč. 18, č. 2 (2009), s. 8-10 ISSN 1210-7409 R&D Projects: GA ČR GA103/07/1016 Institutional research plan: CEZ:AV0Z20600510 Keywords : agitation * aggregation * high rate clarification * velocity gradient * water treatment Subject RIV: BK - Fluid Dynamics

  13. Proces založení a tvorby oděvní značky

    OpenAIRE

    Švach, Martin

    2015-01-01

    The diploma thesis "The Process of Establishing and Building a Fashion Brand" deals with the process of establishing a fashion brand, how to write its business plan and which me- thods and techniques are suitable to use to create a fashion brand. The first part of this thesis covers the issues of establishing small business, then it is explained the structure and utilization of business plan and at the end of the theoretical part is closely described fashion marketing, as well as marketing an...

  14. Proces nabycia przedsiębiorstwa na przykładzie transakcji Adidas-Salomon Group i Reebok Ltd.

    OpenAIRE

    Poparda, Katarzyna

    2011-01-01

    Fuzje i przejęcia przedsiębiorstw stały się popularnym sposobem na poszerzenie pozycji konkurencyjnej przedsiębiorstw w branży producentów strojów, obuwia i sprzętu sportowego. Cel pracy obejmuje przedstawienie istoty fuzji i przejęć oraz metod ich analizy i oceny, a także analizę i ocenę przesłanek, elementów procesu integracji i rezultatów nabycia Reebok Ltd. przez Adidas-Salomon Group. W części empirycznej posłużono się metodyką SWOT i Pięciu Sił M.E. Portera. Źródła danych miały charakter...

  15. Oxidační proces uhlí z pohledu kritické (prahové) teploty

    Czech Academy of Sciences Publication Activity Database

    Taraba, B.; Peter, R.; Slovák, V.; Janek, Jiří

    2005-01-01

    Roč. 53, č. 12 (2005), s. 26-30 ISSN 1210-7697 R&D Projects: GA ČR(CZ) GA105/03/0538; GA ČBÚ(CZ) AACBU29-03 Institutional research plan: CEZ:AV0Z30860518 Keywords : coal oxidation Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  16. Modelacio de sedimentadors en plantes de tractament d'aigues residuals. Aplicacio al proces de fermentacio - elutracio de fangs primaris

    Science.gov (United States)

    Ribes Bertomeu, Josep

    Wastewater treatments require the execution of many conversion processes simultaneously and/or consecutively, making them a tricky object of study. Furthermore, complexity of treatment processes is increasing not only for the more stringent effluent standards required, but also for the new trends towards sustainable development, which in this process are mainly focused on energy saving and nutrient recovery from wastewaters in order to improve their life cycle. For this reason it becomes necessary to use simulation tools which are able to represent all these processes by means of a suitable mathematical model. They can help in determining and predicting the behaviour of the different treatment schemes. These simulators have become essential for the design, control and optimization of wastewater treatment plants (WWTP). Settling processes have a significant role in the accomplishment of effluent standards and the correct operation of the plant. However, many models that are currently employed for WWTP design and simulation do not take into account settling processes or they are handled in a very simple way, by neglecting the biochemical processes that can occur during sedimentation. People of CALAGUA research group have focussed their efforts towards a new philosophy of simulating treatment plants, which is based on the use of a unique model to represent all physical, chemical and biological processes taking place in WWTPs. In this research topic, they have worked on the development of a general quality model that considers biological conversion processes carried out by different microorganism groups, acid base chemical interactions affecting the pH value in the system, and gas-liquid transfer processes. However, a generalized use of such a quality model requires its combination with a flux model, principally for those processes where completely mixture can not be assumed, as for instance, settlers and thickeners in WWTPs. The main objective of this work has been the development and validation of a general settling model that allows simulating the main settling operations taking place in a WWTP, considering both primary and secondary settlers and thickeners. It consists in a one-dimensional model based on the flux theory of Kynch and the double-exponential settling function of Takacs that takes into account flocculation, hindered settling and compression processes. The model has been applied to simulation of settlers and thickeners by means of splitting the system into several horizontal layers, all of them considered as completely mixed reactors which are interconnected by mass flux obtained from the settling model. In order to simulate the conversion processes taking place during sedimentation, the general quality model BNRM1 has been added, and it has been proposed an iterative procedure for solving the equations for each layer in which the settler has been divided. The settling flux model validation, along with the quality model, has been carried out by applying them to a simulation of primary sludge fermentation - elutriation process. This process has been studied on a pilot plant located in the Carraixet WWTP in Alboraia (Valencia). In order to simulate the observed decrease in solids separation efficiency in the studied fermentation - elutriation process, the quality model has been modified with the addition of a new process called "disintegration of complex particulate material". This process influences the settleability of the sludge because it is considered that the disintegrated solids become non-settleable solids. This modification implies the addition of two new kinetic parameters (the specific disintegration velocity for volatile particulate material and the specific disintegration velocity for non volatile particulate material). However, the settling parameter that represents the non-settleable fraction of total suspended solids is eliminated from the model and it has been transformed into an experimental variable which is quite easy to analyze. The result of this modification is a more general model, which is applicable to fermentation - elutriation process working at any operating condition. Finally, the behaviour and capabilities of the developed model have been tested by simulating a complete WWTP on the DESASS simulation software, developed by the research group. This example includes the most important processes that can be used in a WWTP: biological nutrient removal, primary sludge fermentation and sludge digestion. The model allows considering both settling processes and biochemical processes as a whole (denitrification in secondary settlers, primary sludge fermentation and VFA elutriation, phosphorus release in thickeners because of the PAO decay, etc.). The developed model implies an important advance in study of new wastewater treatment processes because it allows dealing with global process optimization problems, by means of full plants simulation. It is very useful for studying the effects of a modification in operation conditions of one element over the operation of the rest of the elements of the WWTP. (Abstract shortened by UMI.).

  17. Proces adaptace nových zaměstnanců ve vybrané společnosti

    OpenAIRE

    Maturová, Inha

    2015-01-01

    This bachelor work focuses on adaptation process of new employees in a particular company. The goal is determination of adaptation process and comparison with needs of the company on onboarding field. A few methods of quality research were used in application part. The first one is analysis of internal documents related to adaptation process. The second is application and analysis of structured inquiry of head of human resources department of the company. Application part of the work brings e...

  18. [Empowerment and power: their relationship in the proces of caring for the chronically ill in primary care].

    Science.gov (United States)

    Riba Bellera, Lydia; Boixadera Vendrell, Mireia; Buendía Surroca, Carmen; Martorell Poveda, Maria Antònia; Piñeiro Méndez, Pilar; Zamora Sánchez, Juan José

    2014-06-01

    The concepts of "power" and "empowerment" are used in various disciplines, both political and social. Now are these terms frequently in the field of health. Our goal is to know its meaning as a synonym of expressions: "energy", "force", "domain", "vigour", "power", "capacity", "authority" and "control", which have been always within our practice nurse's own lexicon. Semantically analyzing them will help us in the understanding of its nuance. The literature review facilitates their understanding and allows us to link these words within the management of care. In this way we can propose diagnoses, interventions and outcomes specifically related to these concepts, which will help us optimize the efficiency in the management of care plans. The purpose of various collective nurses from different institutions is that the person is able to not generate dependencies and have the option of choosing your own lifestyle according to their culture and environment, independently or with the help. Generate knowledge is to generate power. The person should be educated and informed, to be expert and active and taking action to help control and minimize the progression of your health problem chronic and its possible complications. We are in the process of reformulation of the health system, whether it is private or public, and is necessary to know the power of the various actors involved in the management of the care to us. Each of these main actors--person ill, family/caregiver or nurse--has to know what is his role in this process.

  19. Proces adaptace českých občanů na cizí kulturu

    OpenAIRE

    Bakiş, Zuzana

    2016-01-01

    This bachelor thesis deal with the process of adaptation of Czech people to foreign culture, concretely Turkish culture. The thesis focuses on how Czech people perceive Turkish culture and how are they able to adjust to it. The theoretical part explains terms from cross-cultural psychology such as culture, nation, acculturation, adaptation, cultural shock etc. In this part of the thesis are also introduced dimensions of national culture by Geert Hofstede and a comparison of Czech and Turkish ...

  20. Plonalakščio plieno gaminių ir jų gamybos procesų projektavimo integravimas

    OpenAIRE

    Zalieskis, Ramūnas

    2006-01-01

    Zalieskis R. Integration of designing sheet steel products and their manufacturing processes : Master thesis of mechanical engineer / research advisor associate prof. habil. dr. A.Bargelis, Šiauliai university, department of technologic, department of mechanical engineering. – Šiauliai, 2006. – 38 p. Sheet steel is used wide in a modern manufacturing. In this paper I researched the work one of the factories manufacturing sheet steel products. It was analysed all manufacturing operations and e...

  1. Microstructural and constitutive analysis in proces modeling of hot working: the case of a Mg-Zn-Mn alloy

    Czech Academy of Sciences Publication Activity Database

    Spigarelli, S.; Jäger, Aleš; El Mehtedi, M.; Gärtnerová, Viera

    2016-01-01

    Roč. 661, Apr (2016), s. 40-50 ISSN 0921-5093 R&D Projects: GA ČR GBP108/12/G043 Institutional support: RVO:68378271 Keywords : mechanical characterization * EBSD * magnesium alloys * plasticity Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.094, year: 2016

  2. Proces riadenia systému kvality sociálných služieb na Slovensku

    OpenAIRE

    Šebestová, Petronela

    2008-01-01

    The contribution is intended for social service workers who deal with the standards of quality in social services and the complex process of systematic development of quality social services. The road to lasting improvement of the quality is characterized by social service facilities at regular intervals, total self-made assumptions on the CAF model.

  3. Proces kształtowania się strategicznej rachunkowości zarządczej

    OpenAIRE

    Michalak, Jan

    2002-01-01

    The main topic of the article is strategic management accounting. The genesis of strategic management accounting is connected with the changes in economy and the origin of strategic management. Strategic management created new information needs that traditional management accounting could not satisfy. Strategic management accounting consists of new paradigm, features and methods. The most useful methods of strategic management methods are: Target Costing, Life Cycle Costing, ...

  4. Proces manažerského rozhodování v kontextu iracionality rozhodovatele

    OpenAIRE

    Renner, Petr

    2011-01-01

    The diploma thesis deals with the crucial aspect of manager's and leader's role in both public and private organizations -- decision making. It explains the different phases of the decision making process, and then challenges the classical concept based on the theory of rational choice with the results of many experiments outlining a slightly different picture of reality. It seems thought, that human decisions are not fully rational indeed. Despite the availability of advanced methods and too...

  5. Proces tvorby, schvalování a uplatňování IFRS

    OpenAIRE

    Valášková, Mariana

    2010-01-01

    The doctoral thesis examines process of IFRS development, endorsement and enforcement from the perspective of accounting regulation on global scale, identifies nature of IFRS due process in all its phases and compares IFRS due process with accounting regulation in Czech Republic, especially with legislative process of creating Czech accounting legislation. The due process of any accounting rules, whether standards or legislation, determines quality of these rules and consequently also potenti...

  6. Proces správy znalostí ve společnosti Unicorn, a.s.

    OpenAIRE

    Fictum, Luboš

    2009-01-01

    Knowledge as company resource which brings competitive advantage is frequently discussed topic. And managing of knowledge pays increasing attention, because it is possible to maximize utility and minimize losses of knowledge by using appropriate knowledge management. This paper is focused on analysis of Knowledge management process in the context of Unicorn ES Powered Company methodology and on suggestion of possible form of management of the process and its parts, which is the overall goal o...

  7. Mothers and the Process of Social Stratification. De invloed van de moeder op het proces van statusverwerving.

    NARCIS (Netherlands)

    Korupp, Sylvia Elizabeth

    2000-01-01

    The present study embeds the mother's influence into the classical model of status attainment (Blau & Duncan 1967, The American Occupational Structure) that originally was designed to point out status relations between fathers and sons. This model has layed down important methodological foundations

  8. Mothers and the Process of Social Stratification. De invloed van de moeder op het proces van statusverwerving.

    OpenAIRE

    Korupp, Sylvia Elizabeth

    2000-01-01

    The present study embeds the mother's influence into the classical model of status attainment (Blau & Duncan 1967, The American Occupational Structure) that originally was designed to point out status relations between fathers and sons. This model has layed down important methodological foundations upon which much of today's research on social stratification is based. Still most of the research carried out deals only with the relation between the father's and his son's or daughter's socio-eco...

  9. Ošetřovatelský proces u dětského pacienta s epilepsií

    OpenAIRE

    Dvořáková, Martina

    2008-01-01

    The target audiences for the bachelor thesis, Medical Care Process in Pediatric Patients with Epilepsy, are physicians and other health care professionals, nurses and health care assistants in particular. The thesis outlines both theoretical and practical aspects of epilepsy in children patients. The theoretical part summarizes what epilepsy is and what are its causes and symptoms. A list of various kinds of epileptic seizures and syndromes experienced in childhood is provided including a bri...

  10. Modelování business procesů státní správy

    OpenAIRE

    Opálka, Šimon

    2013-01-01

    This Master's thesis focuses on modeling of business processes in public administration sector. The main objective of this study is to compare the ability of selected modeling languages to capture aspects, which are typical for processes in public administration. This objective is reached by elaboration of theoretical part where the terms public administration and business process are defined. Processes are described by their typical characteristic for public government. Based on these charac...

  11. Proces zavádění nového produktu ve franchisingové firmě

    OpenAIRE

    Žďárská, Iva

    2010-01-01

    The bachelor thesis describes the essence of franchising and assumptions for its successful functioning. The origin, development and contemporary situation of franchising in the Czech Republic are explained. Then, necessary conditions of franchising business are analyzed- franchising contract and manual. In the second part, the franchise system McDonald's is described and specified. The main scheme is devoted to the marketing plan and to the implemantation of the new children's product on the...

  12. PROCEDURAL CONVENTION AND FLEXIBILITY OF THE PROCED URE: THE INFLUENCE OF PRIVATE AUTONOMY ON THE PUBLICIST PARADIGM OF CIVIL PROCEDURE

    Directory of Open Access Journals (Sweden)

    Marcelo Dias Ponte

    2015-12-01

    Full Text Available The research aims to analyze the New CPC innovations with regard to the procedural legal business, to assess, carefully, it s possibilities, its limits, requirements and the function of the court and the parties to the flexibility of the procedure. The study approaches the shared management of the procedure, the procedural calendar as materializing institute the principle of efficiency. As a result, it was found that procedural conventions have the power to better protect the substantive rights involved in the dispute, since the litigants may bring the procedural rite to the needs of the conflict, allowing a view democratic demand, able to increase dialogue and interaction between the parties.

  13. Concavity Theorems for Energy Surfaces

    OpenAIRE

    Giraud, B. G.; Karataglidis, S.

    2011-01-01

    Concavity properties prevent the existence of significant landscapes in energy surfaces obtained by strict constrained energy minimizations. The inherent contradiction is due to fluctuations of collective coordinates. A solution to those fluctuations is given.

  14. Total Nitrogen in Surface Water

    Data.gov (United States)

    U.S. Environmental Protection Agency — Excess nitrogen in surface water can result in eutrophication. TOTALN is reported in kilograms/hectare/year. More information about these resources, including the...

  15. Surface electrostatics: theory and computations

    KAUST Repository

    Chatzigeorgiou, G.; Javili, A.; Steinmann, P.

    2014-01-01

    are also expressed in a consistent manner. The theory is accompanied by numerical examples on porous materials using the finite-element method, where the influence of the surface electric permittivity on the electric displacement, the polarization stress

  16. ISLSCP II Sea Surface Temperature

    Data.gov (United States)

    National Aeronautics and Space Administration — Sea surface temperature (SST) is an important indicator of the state of the earth climate system as well as a key variable in the coupling between the atmosphere and...

  17. Building 107 for surface treatment

    CERN Multimedia

    Brice, Maximilien

    2018-01-01

    A brand new state-of-the-art building hosting laboratories for the surface treatment of vacuum equipment and workshops for the manufacturing and treatment of printed circuit boards was completed in 2017.

  18. The structure of stepped surfaces

    International Nuclear Information System (INIS)

    Algra, A.J.

    1981-01-01

    The state-of-the-art of Low Energy Ion Scattering (LEIS) as far as multiple scattering effects are concerned, is discussed. The ion fractions of lithium, sodium and potassium scattered from a copper (100) surface have been measured as a function of several experimental parameters. The ratio of the intensities of the single and double scattering peaks observed in ion scattering spectroscopy has been determined and ion scattering spectroscopy applied in the multiple scattering mode is used to determine the structure of a stepped Cu(410) surface. The average relaxation of the (100) terraces of this surface appears to be very small. The adsorption of oxygen on this surface has been studied with LEIS and it is indicated that oxygen absorbs dissociatively. (C.F.)

  19. Surface Modification for Microreactor Fabrication

    Directory of Open Access Journals (Sweden)

    Wladyslaw Torbicz

    2006-04-01

    Full Text Available In this paper, methods of surface modification of different supports, i.e. glass andpolymeric beads for enzyme immobilisation are described. The developed method ofenzyme immobilisation is based on Schiff’s base formation between the amino groups onthe enzyme surface and the aldehyde groups on the chemically modified surface of thesupports. The surface of silicon modified by APTS and GOPS with immobilised enzymewas characterised by atomic force microscopy (AFM, time-of-flight secondary ion massspectroscopy (ToF-SIMS and infrared spectroscopy (FTIR. The supports withimmobilised enzyme (urease were also tested in combination with microreactors fabricatedin silicon and Perspex, operating in a flow-through system. For microreactors filled withurease immobilised on glass beads (Sigma and on polymeric beads (PAN, a very high andstable signal (pH change was obtained. The developed method of urease immobilisationcan be stated to be very effective.

  20. Wilson loops in minimal surfaces

    International Nuclear Information System (INIS)

    Drukker, Nadav; Gross, David J.; Ooguri, Hirosi

    1999-01-01

    The AdS/CFT correspondence suggests that the Wilson loop of the large N gauge theory with N = 4 supersymmetry in 4 dimensions is described by a minimal surface in AdS 5 x S 5 . The authors examine various aspects of this proposal, comparing gauge theory expectations with computations of minimal surfaces. There is a distinguished class of loops, which the authors call BPS loops, whose expectation values are free from ultra-violet divergence. They formulate the loop equation for such loops. To the extent that they have checked, the minimal surface in AdS 5 x S 5 gives a solution of the equation. The authors also discuss the zig-zag symmetry of the loop operator. In the N = 4 gauge theory, they expect the zig-zag symmetry to hold when the loop does not couple the scalar fields in the supermultiplet. They will show how this is realized for the minimal surface

  1. OW CCMP Ocean Surface Wind

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Cross-Calibrated Multi-Platform (CCMP) Ocean Surface Wind Vector Analyses (Atlas et al., 2011) provide a consistent, gap-free long-term time-series of monthly...

  2. Surface-Enhanced Raman Spectroscopy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 2. Surface-Enhanced Raman Spectroscopy - Recent Advancement of Raman Spectroscopy. Ujjal Kumar Sur. General Article Volume 15 Issue 2 February 2010 pp 154-164 ...

  3. OW ASCAT Ocean Surface Winds

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Advanced Scatterometer (ASCAT) sensor onboard the EUMETSAT MetOp polar-orbiting satellite provides ocean surface wind observations by means of radar...

  4. Thin film surface reconstruction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Imperatori, P [CNR, Monterotondo Stazione, Rome (Italy). Istituto di Chimica dei materiali

    1996-09-01

    The study of the atomic structure of surfaces and interfaces is a fundamental step in the knowledge and the development of new materials. Among the several surface-sensitive techniques employed to characterise the atomic arrangements, grazing incidence x-ray diffraction (GIXD) is one of the most powerful. With a simple data treatment, based on the kinematical theory, and using the classical methods of x-ray bulk structure determination, it gives the atomic positions of atoms at a surface or an interface and the atomic displacements of subsurface layers for a complete determination of the structure. In this paper the main features of the technique will be briefly reviewed and selected of application to semiconductor and metal surfaces will be discussed.

  5. Fracture surfaces of granular pastes.

    Science.gov (United States)

    Mohamed Abdelhaye, Y O; Chaouche, M; Van Damme, H

    2013-11-01

    Granular pastes are dense dispersions of non-colloidal grains in a simple or a complex fluid. Typical examples are the coating, gluing or sealing mortars used in building applications. We study the cohesive rupture of thick mortar layers in a simple pulling test where the paste is initially confined between two flat surfaces. After hardening, the morphology of the fracture surfaces was investigated, using either the box counting method to analyze fracture profiles perpendicular to the mean fracture plane, or the slit-island method to analyze the islands obtained by cutting the fracture surfaces at different heights, parallel to the mean fracture plane. The fracture surfaces were shown to exhibit scaling properties over several decades. However, contrary to what has been observed in the brittle or ductile fracture of solid materials, the islands were shown to be mass fractals. This was related to the extensive plastic flow involved in the fracture process.

  6. Sustaining dry surfaces under water

    DEFF Research Database (Denmark)

    Jones, Paul R.; Hao, Xiuqing; Cruz-Chu, Eduardo R.

    2015-01-01

    Rough surfaces immersed under water remain practically dry if the liquid-solid contact is on roughness peaks, while the roughness valleys are filled with gas. Mechanisms that prevent water from invading the valleys are well studied. However, to remain practically dry under water, additional...... mechanisms need consideration. This is because trapped gas (e.g. air) in the roughness valleys can dissolve into the water pool, leading to invasion. Additionally, water vapor can also occupy the roughness valleys of immersed surfaces. If water vapor condenses, that too leads to invasion. These effects have...... not been investigated, and are critically important to maintain surfaces dry under water.In this work, we identify the critical roughness scale, below which it is possible to sustain the vapor phase of water and/or trapped gases in roughness valleys – thus keeping the immersed surface dry. Theoretical...

  7. The varieties of surface alteration

    International Nuclear Information System (INIS)

    Kelly, R.

    1984-01-01

    Four aspects of ion-beam modification are reviewed: structural changes, in which crystalline phases are converted to amorphous, amorphous phases are converted to crystalline, or ordered crystalline forms evolve to random crystalline forms; topographical changes, which include the development of facets on flat surfaces, the development of cliffs at grain boundaries, the development of ripples on obliquely bombarded surfaces, and the evolution of blunt asperities, foreign particles, or vertical surfaces into cones or pyramids; bombardment-induced electronic changes, which include the consequences of chemical changes due to the composition of the incident beam, carrier injection due to energy deposition, chemical changes due to recoil implantation, and chemical changes due to preferential sputtering; and compositional changes, which in binary alloys consist mainly of a preferential loss of the component with the lower surface binding energy or larger size. 122 refs.; 32 figs.; 9 tabs

  8. Machining of Complex Sculptured Surfaces

    CERN Document Server

    2012-01-01

    The machining of complex sculptured surfaces is a global technological topic in modern manufacturing with relevance in both industrialized and emerging in countries particularly within the moulds and dies sector whose applications include highly technological industries such as the automotive and aircraft industry. Machining of Complex Sculptured Surfaces considers new approaches to the manufacture of moulds and dies within these industries. The traditional technology employed in the manufacture of moulds and dies combined conventional milling and electro-discharge machining (EDM) but this has been replaced with  high-speed milling (HSM) which has been applied in roughing, semi-finishing and finishing of moulds and dies with great success. Machining of Complex Sculptured Surfaces provides recent information on machining of complex sculptured surfaces including modern CAM systems and process planning for three and five axis machining as well as explanations of the advantages of HSM over traditional methods ra...

  9. Causal Dynamics of Discrete Surfaces

    Directory of Open Access Journals (Sweden)

    Pablo Arrighi

    2014-03-01

    Full Text Available We formalize the intuitive idea of a labelled discrete surface which evolves in time, subject to two natural constraints: the evolution does not propagate information too fast; and it acts everywhere the same.

  10. Total Phosphorus in Surface Water

    Data.gov (United States)

    U.S. Environmental Protection Agency — Excess phosphorus in surface water can result in eutrophication. TOTALP is reported in kilograms/hectare/year. More information about these resources, including the...

  11. Free Surface Water Tunnel (FSWT)

    Data.gov (United States)

    Federal Laboratory Consortium — Description: The Free Surface Water Tunnel consists of the intake plenum, the test section and the exit plenum. The intake plenum starts with a perforated pipe that...

  12. Surface energy anisotropy of tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, R; Grenga, H E [Georgia Inst. of Tech., Atlanta (USA). School of Chemical Engineering

    1976-10-01

    Field-ion microscopy was used to study the faceting behavior and/or surface energy anisotropy of tungsten in vacuum and in hydrogen. In vacuum below 1700 K the activation energy for (110) facet growth agreed with values previously reported for surface diffusion on tungsten. The observed anisotropy values at 0.5 Tsub(m), where Tsub(m) is the absolute melting temperature of tungsten (approximately 3680 K), were different from those previously reported at higher temperatures and more nearly agreed with broken bond calculations based on Mie potential using m=5, n=8, and a 1.5% lattice expansion. Hydrogen appeared to have a negligible effect on surface energy anisotropy, but did preferentially increase surface diffusion rates on (310) regions.

  13. Gap Surface Plasmon Waveguide Analysis

    DEFF Research Database (Denmark)

    Nielsen, Michael Grøndahl; Bozhevolnyi, Sergey I.

    2014-01-01

    Plasmonic waveguides supporting gap surface plasmons (GSPs) localized in a dielectric spacer between metal films are investigated numerically and the waveguiding properties at telecommunication wavelengths are presented. Especially, we emphasize that the mode confinement can advantageously...

  14. Surface treatment of ceramic articles

    International Nuclear Information System (INIS)

    Komvopoulos, K.; Brown, I.G.; Wei, B.; Anders, S.; Anders, A.; Bhatia, C.S.

    1998-01-01

    A process is disclosed for producing an article with improved ceramic surface properties including providing an article having a ceramic surface, and placing the article onto a conductive substrate holder in a hermetic enclosure. Thereafter a low pressure ambient is provided in the hermetic enclosure. A plasma including ions of solid materials is produced the ceramic surface of the article being at least partially immersed in a macroparticle free region of the plasma. While the article is immersed in the macroparticle free region, a bias of the substrate holder is biased between a low voltage at which material from the plasma condenses on the surface of the article and a high negative voltage at which ions from the plasma are implanted into the article. 15 figs

  15. Deformations of super Riemann surfaces

    International Nuclear Information System (INIS)

    Ninnemann, H.

    1992-01-01

    Two different approaches to (Konstant-Leites-) super Riemann surfaces are investigated. In the local approach, i.e. glueing open superdomains by superconformal transition functions, deformations of the superconformal structure are discussed. On the other hand, the representation of compact super Riemann surfaces of genus greater than one as a fundamental domain in the Poincare upper half-plane provides a simple description of super Laplace operators acting on automorphic p-forms. Considering purely odd deformations of super Riemann surfaces, the number of linear independent holomorphic sections of arbitrary holomorphic line bundles will be shown to be independent of the odd moduli, leading to a simple proof of the Riemann-Roch theorem for compact super Riemann surfaces. As a further consequence, the explicit connections between determinants of super Laplacians and Selberg's super zeta functions can be determined, allowing to calculate at least the 2-loop contribution to the fermionic string partition function. (orig.)

  16. Deformations of super Riemann surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ninnemann, H [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    1992-11-01

    Two different approaches to (Konstant-Leites-) super Riemann surfaces are investigated. In the local approach, i.e. glueing open superdomains by superconformal transition functions, deformations of the superconformal structure are discussed. On the other hand, the representation of compact super Riemann surfaces of genus greater than one as a fundamental domain in the Poincare upper half-plane provides a simple description of super Laplace operators acting on automorphic p-forms. Considering purely odd deformations of super Riemann surfaces, the number of linear independent holomorphic sections of arbitrary holomorphic line bundles will be shown to be independent of the odd moduli, leading to a simple proof of the Riemann-Roch theorem for compact super Riemann surfaces. As a further consequence, the explicit connections between determinants of super Laplacians and Selberg's super zeta functions can be determined, allowing to calculate at least the 2-loop contribution to the fermionic string partition function. (orig.).

  17. Armor Plate Surface Roughness Measurements

    National Research Council Canada - National Science Library

    Stanton, Brian; Coburn, William; Pizzillo, Thomas J

    2005-01-01

    ...., surface texture and coatings) that could become important at high frequency. We measure waviness and roughness of various plates to know the parameter range for smooth aluminum and rolled homogenous armor (RHA...

  18. Surface morphology of erbium silicide

    International Nuclear Information System (INIS)

    Lau, S.S.; Pai, C.S.; Wu, C.S.; Kuech, T.F.; Liu, B.X.

    1982-01-01

    The surface of rare-earth silicides (Er, Tb, etc.), formed by the reaction of thin-film metal layers with a silicon substrate, is typically dominated by deep penetrating, regularly shaped pits. These pits may have a detrimental effect on the electronic performance of low Schottky barrier height diodes utilizing such silicides on n-type Si. This study suggests that contamination at the metal-Si or silicide-Si interface is the primary cause of surface pitting. Surface pits may be reduced in density or eliminated entirely through either the use of Si substrate surfaces prepared under ultrahigh vacuum conditions prior to metal deposition and silicide formation or by means of ion irradiation techniques. Silicide layers formed by these techniques possess an almost planar morphology

  19. Surface Meteorology and Solar Energy

    Data.gov (United States)

    National Aeronautics and Space Administration — Surface Meteorology and Solar Energy data - over 200 satellite-derived meteorology and solar energy parameters, monthly averaged from 22 years of data, global solar...

  20. Surface engineering and environmental issues

    International Nuclear Information System (INIS)

    Aguero, A.

    2007-01-01

    Surface engineering addresses the modification of the microstructure and/or composition of the surface of components by mechanical, physical or chemical methods that may imply adding a material in order to change the surface properties of said components. One of its most important consequences is the significant increase of the useful life of a variety of components in a large number of industrial applications. Moreover, it contributes to energy savings by increasing efficiencies as it allows higher combustion temperatures, by allowing the use of lighter components and by significant friction reduction. In this paper, surface engineering is introduced, as well as its different modalities, examples of industrial applications and positive and negative environmental impacts. (Author) 29 refs

  1. Wilson loops and minimal surfaces

    International Nuclear Information System (INIS)

    Drukker, Nadav; Gross, David J.; Ooguri, Hirosi

    1999-01-01

    The AdS-CFT correspondence suggests that the Wilson loop of the large N gauge theory with N=4 supersymmetry in four dimensions is described by a minimal surface in AdS 5 xS 5 . We examine various aspects of this proposal, comparing gauge theory expectations with computations of minimal surfaces. There is a distinguished class of loops, which we call BPS loops, whose expectation values are free from ultraviolet divergence. We formulate the loop equation for such loops. To the extent that we have checked, the minimal surface in AdS 5 xS 5 gives a solution of the equation. We also discuss the zigzag symmetry of the loop operator. In the N=4 gauge theory, we expect the zigzag symmetry to hold when the loop does not couple the scalar fields in the supermultiplet. We will show how this is realized for the minimal surface. (c) 1999 The American Physical Society

  2. The spectrum of hyperbolic surfaces

    CERN Document Server

    Bergeron, Nicolas

    2016-01-01

    This text is an introduction to the spectral theory of the Laplacian on compact or finite area hyperbolic surfaces. For some of these surfaces, called “arithmetic hyperbolic surfaces”, the eigenfunctions are of arithmetic nature, and one may use analytic tools as well as powerful methods in number theory to study them. After an introduction to the hyperbolic geometry of surfaces, with a special emphasis on those of arithmetic type, and then an introduction to spectral analytic methods on the Laplace operator on these surfaces, the author develops the analogy between geometry (closed geodesics) and arithmetic (prime numbers) in proving the Selberg trace formula. Along with important number theoretic applications, the author exhibits applications of these tools to the spectral statistics of the Laplacian and the quantum unique ergodicity property. The latter refers to the arithmetic quantum unique ergodicity theorem, recently proved by Elon Lindenstrauss. The fruit of several graduate level courses at Orsay...

  3. Decontamination of radioactively contaminated surfaces

    International Nuclear Information System (INIS)

    1986-10-01

    By this standard objective conditions to evaluate and test the ease of decontamination of surfaces under laboratory conditions are to be laid down. Ease of decontamination in this context denotes the summed-up effect of two material properties: a) the capacity of the material for retaining radioactive substances at its surface; b) the ease with which these substances are given off again in the course of cleaning processes. (orig./HP) [de

  4. Vacancy clusters at nanoparticle surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Xu, J.; Moxom, J.; Somieski, B.; White, C.W. [Oak Ridge National Lab., TN (United States); Mills, A.P. Jr. [Bell Labs., Lucent Technologies, Murray Hill, NJ (United States); Suzuki, R.; Ishibashi, S. [Electrotechnical Lab., Tsukuba, Ibaraki (Japan); Ueda, A.; Henderson, D. [Physics Dept., Fisk Univ., Nashville, TN (United States)

    2001-07-01

    We detect vacancy clusters at Au nanoparticle surfaces using a combination of positron lifetime spectroscopy, 1- detector, and 2-detector measurements of Doppler broadening of annihilation radiation. Gold nanoparticles are formed by MeV implantation of gold ions into MgO (100) followed by annealing. Clusters of two Mg and two O vacancies (v{sub 4}) are attached to the gold nanoparticle surfaces within the projected range (R{sub p}). (orig.)

  5. Vacancy clusters at nanoparticle surfaces

    International Nuclear Information System (INIS)

    Xu, J.; Moxom, J.; Somieski, B.; White, C.W.; Mills, A.P. Jr.; Suzuki, R.; Ishibashi, S.; Ueda, A.; Henderson, D.

    2001-01-01

    We detect vacancy clusters at Au nanoparticle surfaces using a combination of positron lifetime spectroscopy, 1- detector, and 2-detector measurements of Doppler broadening of annihilation radiation. Gold nanoparticles are formed by MeV implantation of gold ions into MgO (100) followed by annealing. Clusters of two Mg and two O vacancies (v 4 ) are attached to the gold nanoparticle surfaces within the projected range (R p ). (orig.)

  6. Corrosion-resistant metal surfaces

    Science.gov (United States)

    Sugama, Toshifumi [Wading River, NY

    2009-03-24

    The present invention relates to metal surfaces having thereon an ultrathin (e.g., less than ten nanometer thickness) corrosion-resistant film, thereby rendering the metal surfaces corrosion-resistant. The corrosion-resistant film includes an at least partially crosslinked amido-functionalized silanol component in combination with rare-earth metal oxide nanoparticles. The invention also relates to methods for producing such corrosion-resistant films.

  7. Liouville gravity on bordered surfaces

    International Nuclear Information System (INIS)

    Jaskolski, Z.

    1991-11-01

    The functional quantization of the Liouville gravity on bordered surfaces in the conformal gauge is developed. It was shown that the geometrical interpretation of the Polyakov path integral as a sum over bordered surfaces uniquely determines the boundary conditions for the fields involved. The gravitational scaling dimensions of boundary and bulk operators and the critical exponents are derived. In particular, the boundary Hausdorff dimension is calculated. (author). 21 refs

  8. Critical behavior of collapsing surfaces

    DEFF Research Database (Denmark)

    Olsen, Kasper; Sourdis, C.

    2009-01-01

    We consider the mean curvature evolution of rotationally symmetric surfaces. Using numerical methods, we detect critical behavior at the threshold of singularity formation resembling that of gravitational collapse. In particular, the mean curvature simulation of a one-parameter family of initial...... data reveals the existence of a critical initial surface that develops a degenerate neckpinch. The limiting flow of the type II singularity is accurately modeled by the rotationally symmetric translating soliton....

  9. DETERMINATION OF RADIATOR COOLING SURFACE

    Directory of Open Access Journals (Sweden)

    A. I. Yakubovich

    2009-01-01

    Full Text Available The paper proposes a methodology for calculation of a radiator cooling surface with due account of heat transfer non-uniformity on depth of its core. Calculation of radiator cooling surfaces of «Belarus-1221» and «Belarus-3022» tractors has been carried out in the paper. The paper also advances standard size series of radiators for powerful «Belarus» tractor type.

  10. Stretch-minimising stream surfaces

    KAUST Repository

    Barton, Michael; Kosinka, Jin; Calo, Victor M.

    2015-01-01

    We study the problem of finding stretch-minimising stream surfaces in a divergence-free vector field. These surfaces are generated by motions of seed curves that propagate through the field in a stretch minimising manner, i.e., they move without stretching or shrinking, preserving the length of their arbitrary arc. In general fields, such curves may not exist. How-ever, the divergence-free constraint gives rise to these 'stretch-free' curves that are locally arc-length preserving when infinitesimally propagated. Several families of stretch-free curves are identified and used as initial guesses for stream surface generation. These surfaces are subsequently globally optimised to obtain the best stretch-minimising stream surfaces in a given divergence-free vector field. Our algorithm was tested on benchmark datasets, proving its applicability to incompressible fluid flow simulations, where our stretch-minimising stream surfaces realistically reflect the flow of a flexible univariate object. © 2015 Elsevier Inc. All rights reserved.

  11. Stretch-minimising stream surfaces

    KAUST Repository

    Barton, Michael

    2015-05-01

    We study the problem of finding stretch-minimising stream surfaces in a divergence-free vector field. These surfaces are generated by motions of seed curves that propagate through the field in a stretch minimising manner, i.e., they move without stretching or shrinking, preserving the length of their arbitrary arc. In general fields, such curves may not exist. How-ever, the divergence-free constraint gives rise to these \\'stretch-free\\' curves that are locally arc-length preserving when infinitesimally propagated. Several families of stretch-free curves are identified and used as initial guesses for stream surface generation. These surfaces are subsequently globally optimised to obtain the best stretch-minimising stream surfaces in a given divergence-free vector field. Our algorithm was tested on benchmark datasets, proving its applicability to incompressible fluid flow simulations, where our stretch-minimising stream surfaces realistically reflect the flow of a flexible univariate object. © 2015 Elsevier Inc. All rights reserved.

  12. Radioactive Ions for Surface Characterization

    CERN Multimedia

    2002-01-01

    The collaboration has completed a set of pilot experiments with the aim to develop techniques for using radioactive nuclei in surface physics. The first result was a method for thermal deposition of isolated atoms (Cd, In, Rb) on clean metallic surfaces. \\\\ \\\\ Then the diffusion history of deposited Cd and In atoms on two model surfaces, Mo(110) and Pd(111), was followed through the electric field gradients (efg) acting at the probe nuclei as measured with the Perturbed Angular Correlation technique. For Mo(110) a rather simple history of the adatoms was inferred from the experiments: Atoms initially landing at terrace sites diffuse from there to ledges and then to kinks, defects always present at real surfaces. The next stage is desorption from the surface. For Pd a scenario that goes still further was found. Following the kink stage the adatoms get incorporated into ledges and finally into the top surface layer. For all these five sites the efg's could be measured.\\\\ \\\\ In preparation for a further series o...

  13. The chemical physics of surfaces

    CERN Document Server

    Morrison, Stanley Roy

    1990-01-01

    Even more importantly, some authors who have contributed substantially to an area may have been overlooked. For this I apologize. I have, however, not attempted to trace techniques or observa­ tions historically, so there is no implication (unless specified) that the authors referred to were or were not the originators of a given method or observation. I would like to acknowledge discussions with co-workers at SFU for input relative to their specialties, to acknowledge the help of students who have pointed out errors and difficulties in the earlier presentation, and to acknowledge the infinite patience of my wife Phyllis while I spent my sabbatical and more in libraries and punching computers. S. Roy Morrison 0 1 Contents Notation XV 1. Introduction 1 1. 1. Surface States and Surface Sites . 1 1. 1. 1. The Chemical versus Electronic Representation of the Surface. 1 1. 1. 2. The Surface State on the Band Diagram 4 1. 1. 3. The Fermi Energy in the Surface State Model. 6 1. 1. 4. Need for Both Surface...

  14. Spectrophotometry of the Ceres surface

    Science.gov (United States)

    Schröder, Stefan; Mottola, Stefano; Carsenty, Uri; Jaumann, Ralf; Keller, Uwe; Krohn, Katrin; Li, Jian-Yang; Matz, Klaus-Dieter; McFadden, Lucy; Otto, Katharina; Preusker, Frank; Roatsch, Thomas; Scholten, Frank; Stephan, Katrin; Wagner, Roland; Raymond, Carol; Russell, Chris

    2015-11-01

    The Dawn spacecraft is in orbit around dwarf planet Ceres. The onboard Framing Camera (FC) is mapping the surface through a clear filter and 7 narrow-band filters at various observational geometries and image resolutions. Generally, Ceres' appearance in these images is affected by shadows and shading, effects which obscure the intrinsic reflective properties of the surface. By means of photometric modeling we remove these effects and reconstruct the surface reflectance for each of the FC filters, creating albedo and color maps in the process. Considering these maps in unison provides clues to the physical nature and composition of the surface and the dominant geologic processes that shape the surface. We assess the nature of color variations in the visible wavelength range for Ceres globally. We identify which terrains express the dominant colors and investigate why some areas are exceptions to the rule. By correlating the color over the surface with geologic units we find an relatively strong enhancement of the reflectance towards the blue end of the visible spectrum for recent impacts and their ejecta.

  15. The surface modification of polystyrene

    International Nuclear Information System (INIS)

    Tremlett, C.

    2000-03-01

    Polymers have ideal bulk properties for many applications. However, adhesion to many polymers is poor without surface pretreatment. This can result, for example, in peeling paint and printing, adhesive joint failure and bio-incompatibility. In applications such as painting, printing, adhesive bonding and biocompatibility, various cleaning or surface chemical modifications may be employed. A commodity polymer where pretreatment is sometimes needed is polystyrene. This project investigated, in detail, the effects of a novel method of modification namely mediated electrochemical oxidation (MEO), as a mode of surface modification on polystyrene and a comparison was made with other polymers. The resulting modification was investigated using a range of surface analysis techniques to obtain complementary information. These included, X-ray photoelectron spectroscopy, contact angles, static secondary ion mass spectrometry, atomic force microscopy, chemical derivatization, scanning electron microscopy, attenuated total reflection Fourier Transform infrared spectroscopy and composite lap shear joint testing. It has been shown that MEO modifies the surface of polystyrene introduced oxygen mainly as hydroxyl groups, and a small number of carbonyl groups, that are positioned only on the backbone hydrocarbon chain. This modification improved adhesion, was stable and samples could be stored in aqueous media. The resulting hydroxylation was further derivatized using an amino acid to provide a specialised surface. This was very different from the multiple oxygen functionalities introduced in the comparison studies by UV/ozone and plasma treatments. (author)

  16. Comment on 'Surface thermodynamics, surface stress, equations at surfaces and triple lines for deformable bodies'

    International Nuclear Information System (INIS)

    Gutman, E M

    2010-01-01

    In a recent publication by Olives (2010 J. Phys.: Condens. Matter 22 085005) he studied 'the thermodynamics and mechanics of the surface of a deformable body, following and refining the general approach of Gibbs' and believed that 'a new definition of the surface stress is given'. However, using the usual way of deriving the equations of Gibbs-Duhem type the author, nevertheless, has fallen into a mathematical discrepancy because he has tried to unite in one equation different thermodynamic systems and 'a new definition of the surface stress' has appeared known in the usual theory of elasticity. (comment)

  17. Ion neutralization at metal surfaces by surface-plasmon excitation

    International Nuclear Information System (INIS)

    Almulhem, A.A.

    1988-01-01

    Electron capture by ions scattered from metal surfaces is usually assumed to occur via resonance tunneling or Auger neutralization. A new mechanism is proposed, wherein a surface plasmon is excited during the electron capture. The Fock-Tani transformation is used to transform the Hamiltonian into a form which explicitly contains a term that corresponds to this process. Using this term, the matrix elements are calculated analytically and used to evaluate the transition rate as a function of distance from the surface. Since this is a rearrangement process, the matrix element contains an orthogonalization term. The theory is applied to the scattering of protons from an aluminum surface in which the proton captures an electron into the 1s state. From the results obtained for the transition rate and neutral fractions, it is concluded that this process is important, at least in the low energy region. When the calculations are done with the orthogonalization term in the matrix element neglected, the transition rate and neutral fraction increased appreciably. This shows the importance of this term, and implies that it cannot be neglected as was done in other theories of neutralization at metal surfaces

  18. Surface-to-surface registration using level sets

    DEFF Research Database (Denmark)

    Hansen, Mads Fogtmann; Erbou, Søren G.; Vester-Christensen, Martin

    2007-01-01

    This paper presents a general approach for surface-to-surface registration (S2SR) with the Euclidean metric using signed distance maps. In addition, the method is symmetric such that the registration of a shape A to a shape B is identical to the registration of the shape B to the shape A. The S2SR...... problem can be approximated by the image registration (IR) problem of the signed distance maps (SDMs) of the surfaces confined to some narrow band. By shrinking the narrow bands around the zero level sets the solution to the IR problem converges towards the S2SR problem. It is our hypothesis...... that this approach is more robust and less prone to fall into local minima than ordinary surface-to-surface registration. The IR problem is solved using the inverse compositional algorithm. In this paper, a set of 40 pelvic bones of Duroc pigs are registered to each other w.r.t. the Euclidean transformation...

  19. Surface and body waves from surface and underground explosions

    International Nuclear Information System (INIS)

    Kusubov, A.S.

    1976-06-01

    The characteristics of surface and ground waves were recorded for surface and underground explosions up to 100 tons and 40 kt in magnitude, respectively, and a preliminary analysis of these results is presented. The experiments were conducted at NTS in the Yucca Flats, Nevada. Ground motions were detected with triaxial geophones along seismic lines extending up to 16 miles from the point of explosions. A comparison of Rayleigh waves generated by surface and underground explosions in the same lake bed is presented indicating a very different behavior of surface and ground waves from the two types of explosions. The magnitude of the transverse wave for surface shots was smaller by a factor of two than its longitudinal counterpart. The dependence of apparent periods on the blast energy was not apparent at a fixed distance from the explosions. Changes in the apparent period with distance for both types of explosion are compared indicating a strong layering effect of the lake bed. The ground motion study was complimented by excavation of cavities generated by the explosions

  20. Applications of surface analysis and surface theory in tribology

    Science.gov (United States)

    Ferrante, John

    1989-01-01

    Tribology, the study of adhesion, friction and wear of materials, is a complex field which requires a knowledge of solid state physics, surface physics, chemistry, material science, and mechanical engineering. It has been dominated, however, by the more practical need to make equipment work. With the advent of surface analysis and advances in surface and solid-state theory, a new dimension has been added to the analysis of interactions at tribological interfaces. In this paper the applications of tribological studies and their limitations are presented. Examples from research at the NASA Lewis Research Center are given. Emphasis is on fundamental studies involving the effects of monolayer coverage and thick films on friction and wear. A summary of the current status of theoretical calculations of defect energetics is presented. In addition, some new theoretical techniques which enable simplified quantitative calculations of adhesion, fracture, and friction are discussed.

  1. Polygon formation and surface flow on a rotating fluid surface

    DEFF Research Database (Denmark)

    Bergmann, Raymond; Tophøj, Laust Emil Hjerrild; Homan, T. A. M.

    2011-01-01

    We present a study of polygons forming on the free surface of a water flow confined to a stationary cylinder and driven by a rotating bottom plate as described by Jansson et al. (Phys. Rev. Lett., vol. 96, 2006, 174502). In particular, we study the case of a triangular structure, either completely...... there the symmetry breaking proceeds like a low-dimensional linear instability. We show that the circular state and the unstable manifold connecting it with the polygon solution are universal in the sense that very different initial conditions lead to the same circular state and unstable manifold. For a wet triangle......, we measure the surface flows by particle image velocimetry (PIV) and show that there are three vortices present, but that the strength of these vortices is far too weak to account for the rotation velocity of the polygon. We show that partial blocking of the surface flow destroys the polygons and re...

  2. Alpha detection on moving surfaces

    International Nuclear Information System (INIS)

    MacArthur, D.; Orr, C.; Luff, C.

    1998-01-01

    Both environmental restoration (ER) and decontamination and decommissioning (D and D) require characterization of large surface areas (walls, floors, in situ soil, soil and rubble on a conveyor belt, etc.) for radioactive contamination. Many facilities which have processed alpha active material such as plutonium or uranium require effective and efficient characterization for alpha contamination. Traditional methods for alpha surface characterization are limited by the short range and poor penetration of alpha particles. These probes are only sensitive to contamination located directly under the probe. Furthermore, the probe must be held close to the surface to be monitored in order to avoid excessive losses in the ambient air. The combination of proximity and thin detector windows can easily cause instrument damage unless extreme care is taken. The long-range alpha detection (LRAD) system addresses these problems by detecting the ions generated by alpha particles interacting with ambient air rather than the alpha particle directly. Thus, detectors based on LRAD overcome the limitations due to alpha particle range (the ions can travel many meters as opposed to the several-centimeter alpha particle range) and penetrating ability (an LRAD-based detector has no window). Unfortunately, all LRAD-based detectors described previously are static devices, i.e., these detectors cannot be used over surfaces which are continuously moving. In this paper, the authors report on the first tests of two techniques (the electrostatic ion seal and the gridded electrostatic LRAD detector) which extend the capabilities of LRAD surface monitors to use over moving surfaces. This dynamic surface monitoring system was developed jointly by Los Alamos National Laboratory and at BNFL Instruments. All testing was performed at the BNFL Instruments facility in the UK

  3. Vicinal surfaces for functional nanostructures.

    Science.gov (United States)

    Tegenkamp, Christoph

    2009-01-07

    Vicinal surfaces are currently the focus of research. The regular arrangements of atomic steps on a mesoscopic scale reveal the possibility to functionalize these surfaces for technical applications, e.g. nanowires, catalysts, etc. The steps of the vicinal surface are well-defined defect structures of atomic size for nucleation of low-dimensional nanostructures. The concentration and therefore the coupling between the nanostructures can be tuned over a wide range by simply changing the inclination angle of the substrate. However, the coupling of these nano-objects to the substrate is just as important in controlling their electronic or chemical properties and making a functionality useable. On the basis of stepped insulating films, these aspects are fulfilled and will be considered in the first part of this review. Recent results for the epitaxial growth of wide bandgap insulating films (CaF(2), MgO, NaCl, BaSrO) on metallic and semiconducting vicinal substrates (Si(100), Ge(100), Ag(100)) will be presented. The change of the electronic structure, the adsorption behavior as well as the kinetics and energetics of color centers in the presence of steps is discussed. The successful bridging of the gap between the atomic and mesoscopic world, i.e. the functionalization of vicinal surfaces by nanostructures, is demonstrated in the second part by metal adsorption on semiconducting surfaces. For (sub)monolayer coverage these systems have in common that the surface states do not hybridize with the support, i.e. the semiconducting surfaces are insulating. Here I will focus on the latest results of macroscopic transport measurements on Pb quantum wires grown on vicinal Si(111) showing indeed a one-dimensional transport behavior.

  4. Vicinal surfaces for functional nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Tegenkamp, Christoph [Institut fuer Festkoerperphysik, Gottfried Wilhelm Leibniz Universitaet Hannover, Appelstrasse 2, D-30167 Hannover (Germany)], E-mail: tegenkamp@fkp.uni-hannover.de

    2009-01-07

    Vicinal surfaces are currently the focus of research. The regular arrangements of atomic steps on a mesoscopic scale reveal the possibility to functionalize these surfaces for technical applications, e.g. nanowires, catalysts, etc. The steps of the vicinal surface are well-defined defect structures of atomic size for nucleation of low-dimensional nanostructures. The concentration and therefore the coupling between the nanostructures can be tuned over a wide range by simply changing the inclination angle of the substrate. However, the coupling of these nano-objects to the substrate is just as important in controlling their electronic or chemical properties and making a functionality useable. On the basis of stepped insulating films, these aspects are fulfilled and will be considered in the first part of this review. Recent results for the epitaxial growth of wide bandgap insulating films (CaF{sub 2}, MgO, NaCl, BaSrO) on metallic and semiconducting vicinal substrates (Si(100), Ge(100), Ag(100)) will be presented. The change of the electronic structure, the adsorption behavior as well as the kinetics and energetics of color centers in the presence of steps is discussed. The successful bridging of the gap between the atomic and mesoscopic world, i.e. the functionalization of vicinal surfaces by nanostructures, is demonstrated in the second part by metal adsorption on semiconducting surfaces. For (sub)monolayer coverage these systems have in common that the surface states do not hybridize with the support, i.e. the semiconducting surfaces are insulating. Here I will focus on the latest results of macroscopic transport measurements on Pb quantum wires grown on vicinal Si(111) showing indeed a one-dimensional transport behavior. (topical review)

  5. Vicinal surfaces for functional nanostructures

    International Nuclear Information System (INIS)

    Tegenkamp, Christoph

    2009-01-01

    Vicinal surfaces are currently the focus of research. The regular arrangements of atomic steps on a mesoscopic scale reveal the possibility to functionalize these surfaces for technical applications, e.g. nanowires, catalysts, etc. The steps of the vicinal surface are well-defined defect structures of atomic size for nucleation of low-dimensional nanostructures. The concentration and therefore the coupling between the nanostructures can be tuned over a wide range by simply changing the inclination angle of the substrate. However, the coupling of these nano-objects to the substrate is just as important in controlling their electronic or chemical properties and making a functionality useable. On the basis of stepped insulating films, these aspects are fulfilled and will be considered in the first part of this review. Recent results for the epitaxial growth of wide bandgap insulating films (CaF 2 , MgO, NaCl, BaSrO) on metallic and semiconducting vicinal substrates (Si(100), Ge(100), Ag(100)) will be presented. The change of the electronic structure, the adsorption behavior as well as the kinetics and energetics of color centers in the presence of steps is discussed. The successful bridging of the gap between the atomic and mesoscopic world, i.e. the functionalization of vicinal surfaces by nanostructures, is demonstrated in the second part by metal adsorption on semiconducting surfaces. For (sub)monolayer coverage these systems have in common that the surface states do not hybridize with the support, i.e. the semiconducting surfaces are insulating. Here I will focus on the latest results of macroscopic transport measurements on Pb quantum wires grown on vicinal Si(111) showing indeed a one-dimensional transport behavior. (topical review)

  6. Artefacts for optical surface measurement

    Science.gov (United States)

    Robson, Stuart; Beraldin, J.-Angelo; Brownhill, Andrew; MacDonald, Lindsay

    2011-07-01

    Flexible manufacturing technologies are supporting the routine production of components with freeform surfaces in a wide variety of materials and surface finishes. Such surfaces may be exploited for both aesthetic and performance criteria for a wide range of industries, for example automotive, aircraft, small consumer goods and medial components. In order to ensure conformance between manufactured part and digital design it is necessary to understand, validate and promote best practice of the available measurement technologies. Similar, but currently less quantifiable, measurement requirements also exist in heritage, museum and fine art recording where objects can be individually hand crafted to extremely fine levels of detail. Optical 3D measurement systems designed for close range applications are typified by one or more illumination sources projecting a spot, line or structured light pattern onto a surface or surfaces of interest. Reflections from the projected light are detected in one or more imaging devices and measurements made concerning the location, intensity and optionally colour of the image. Coordinates of locations on the surface may be computed either directly from an understanding of the illumination and imaging geometry or indirectly through analysis of the spatial frequencies of the projected pattern. Regardless of sensing configuration some independent means is necessary to ensure that measurement capability will meet the requirements of a given level of object recording and is consistent for variations in surface properties and structure. As technologies mature, guidelines for best practice are emerging, most prominent at the current time being the German VDI/VDE 2634 and ISO/DIS 10360-8 guidelines. This considers state of the art capabilities for independent validation of optical non-contact measurement systems suited to the close range measurement of table top sized manufactured or crafted objects.

  7. The age of Titan's surface

    Science.gov (United States)

    Neish, C. D.; Lorenz, R. D.

    2010-04-01

    High-resolution images of the surface of Titan taken by the Cassini spacecraft reveal a world with an extreme paucity of impact craters. Planetary surfaces are commonly dated by dividing the number of impact craters by the estimated impactor flux, but this approach has been confounded at Titan by several difficulties. First, high-resolution imaging of the surface of Titan is far from complete (in the near-infrared as well as radar). As of December 2007, Cassini RADAR images covered only 22% of its surface. However, we can use Monte-Carlo models to explore how many craters of a given size (with large or very large craters being of particular interest) may be present in the unobserved areas. Second, literature descriptions of the crater formation rate (e.g. Korycansky and Zahnle 2005 and Artemieva and Lunine 2005) are apparently not in agreement. We discuss possible resolutions. Third, since surface modification processes are ongoing, the actual number of craters on Titan's surface remains uncertain, as craters may be eroded beyond recognition, or obscured by lakes or sand seas. In this connection, we use the Earth as an analogue. The Earth is in many ways the most "Titan-like" world in the solar system, with extensive modification by erosion, burial, tectonism, and volcanism. We compare the observed number of terrestrial craters to the expected terrestrial impactor flux to determine the crater reduction factor for a world similar to Titan. From this information, we can back out the actual number of craters on Titan's surface and estimate its crater retention age. An accurate age estimate will be critical for constraining models of Titan's formation and evolution.

  8. ASSESSMENT OF SURFACE QUALITY FOR CHOSEN MILLING STRATEGIES WHEN PRODUCING RELIEF SURFACES

    OpenAIRE

    Jan Varga; Jozef Stahovec; Jozef Beno; Marek Vrabeľ

    2014-01-01

    The paper deals with design and modeling of the relief surfaces that are produced in milling. Modeled and real surface quality is presented for the chosen fragments of the relief surfaces. Fragmentation of the relief surfaces has been made by the surface sampling. Milling strategies are compared with regard to surface formation. Surface quality was checked with regard to applied cutting conditions.

  9. Surface renewal analysis for estimating turbulent surface fluxes

    International Nuclear Information System (INIS)

    Castellvi, F.

    2009-01-01

    A decade ago, the need for a long-term surface monitoring was recognized to better understand the soil-vegetation-atmosphere scalar exchange and interaction processes. the AmeriFlux concept emerged in the IGBP workshop (La Thuile, IT, 1995). Continuous acquisition of surface fluxes for different species such as temperature, water vapour, CO x , halocarbon, ozone, etc.,) and momentum allows determination of the influence of local (canopy) exchanges, fossil fuel emission, large-scale biotic exchange on ambient concentrations which are crucial to take decisions for protecting natural environments and water resources, to develop new perspective for modern agriculture and forest management and to better understand the global climate change. (Author)

  10. Scattered surface charge density: A tool for surface characterization

    KAUST Repository

    Naydenov, Borislav; Mantega, Mauro; Rungger, Ivan; Sanvito, Stefano; Boland, John J.

    2011-01-01

    We demonstrate the use of nonlocal scanning tunneling spectroscopic measurements to characterize the local structure of adspecies in their states where they are significantly less perturbed by the probe, which is accomplished by mapping the amplitude and phase of the scattered surface charge density. As an example, we study single-H-atom adsorption on the n-type Si(100)-(4 × 2) surface, and demonstrate the existence of two different configurations that are distinguishable using the nonlocal approach and successfully corroborated by density functional theory. © 2011 American Physical Society.

  11. Scattered surface charge density: A tool for surface characterization

    KAUST Repository

    Naydenov, Borislav

    2011-11-28

    We demonstrate the use of nonlocal scanning tunneling spectroscopic measurements to characterize the local structure of adspecies in their states where they are significantly less perturbed by the probe, which is accomplished by mapping the amplitude and phase of the scattered surface charge density. As an example, we study single-H-atom adsorption on the n-type Si(100)-(4 × 2) surface, and demonstrate the existence of two different configurations that are distinguishable using the nonlocal approach and successfully corroborated by density functional theory. © 2011 American Physical Society.

  12. Surface study of liquid 3He using surface state electrons

    International Nuclear Information System (INIS)

    Shirahama, K.; Ito, S.; Suto, H.; Kono, K.

    1995-01-01

    We have measured the mobility of surface state electrons (SSE) on liquid 3 He, μ 3 , aiming to study the elementary surface excitations of the Fermi liquid. A gradual increase of μ 3 below 300 mK is attributed to the scattering of electrons by ripplons. Ripplons do exist in 3 He down to 100 mK. We observe an abrupt decrease of μ 3 , due to the transition to the Wigner solid (WS). The dependences of the WS conductivity and mobility on temperature and magnetic field differ from the SSE behavior on liquid 4 He

  13. Dynamical modeling of surface tension

    International Nuclear Information System (INIS)

    Brackbill, J.U.; Kothe, D.B.

    1996-01-01

    In a recent review it is said that free-surface flows ''represent some of the difficult remaining challenges in computational fluid dynamics''. There has been progress with the development of new approaches to treating interfaces, such as the level-set method and the improvement of older methods such as the VOF method. A common theme of many of the new developments has been the regularization of discontinuities at the interface. One example of this approach is the continuum surface force (CSF) formulation for surface tension, which replaces the surface stress given by Laplace's equation by an equivalent volume force. Here, we describe how CSF might be made more useful. Specifically, we consider a derivation of the CSF equations from a minimization of surface energy as outlined by Jacqmin. This reformulation suggests that if one eliminates the computation of curvature in terms of a unit normal vector, parasitic currents may be eliminated For this reformulation to work, it is necessary that transition region thickness be controlled. Various means for this, in addition to the one discussed by Jacqmin are discussed

  14. Ion bombardment modification of surfaces

    International Nuclear Information System (INIS)

    Auciello, O.

    1984-01-01

    Ion bombardment-induced modification of surfaces may be considered one of the significant scientific and technological developments of the last two decades. The understanding acquired concerning the underlying mechanisms of several phenomena occurring during ion-surface interactions has led to applications within different modern technologies. These include microelectronics, surface acoustical and optical technologies, solar energy conversion, thin film technology, ion implantation metallurgy, nuclear track technology, thermonuclear fusion, vacuum technology, cold welding technology, biomedicine (implantology). It has become clear that information on many relevant advances, regarding ion bombardment modification of surfaces is dispersed among journals involving fields sometimes not clearly related. This may result, in some cases, in a loss of the type of interdisciplinary exchange of ideas, which has proved to be so fruitful for the advancement of science and technology. This book has been planned in an attempt to collect at least some of today's relevant information about the experimental and theoretical knowledge related to surface modification and its application to technology. (Auth.)

  15. Surface and interior of Venus

    Energy Technology Data Exchange (ETDEWEB)

    Masursky, H [U.S. Geological Survey, Flagstaff, Arizona, USA; Kaula, W M [California Univ., Los Angeles (USA); McGill, G E [Massachusetts Univ., Amherst (USA); Pettengill, G H; Shapiro, I I [Massachusetts Inst. of Tech., Cambridge (USA). Dept. of Earth and Planetary Sciences; Phillips, R J [Jet Propulsion Lab., Pasadena, Calif. (USA); Russell, C T [California Univ., Los Angeles (USA). Inst. of Geophysics and Planetary Physics; Schubert, G [California Univ., Los Angeles (USA)

    1977-06-01

    Present ideas about the surface and interior of Venus are based on data obtained from (1) Earth-based radio and radar: temperature, rotation, shape, and topography; (2) fly-by and orbiting spacecraft: gravity and magnetic fields; and (3) landers: winds, local structure, gamma radiation. Surface features, including large basins, crater-like depressions, and a linear valley, have been recognized from recent ground-based radar images. Pictures of the surface acquired by the USSR's Venera 9 and 10 show abundant boulders and apparent wind erosion. On the Pioneer Venus 1978 Orbiter mission, the radar mapper experiment will determine surface heights, dielectric constant values and small-scale slope values along the sub-orbital track between 50/sup 0/S and 75/sup 0/N. This experiment will also estimate the global shape and provide coarse radar images (40-80 km identification resolution) of part of the surface. Gravity data will be obtained by radio tracking. Maps combining radar altimetry with spacecraft and ground-based images will be made. A fluxgate magnetometer will measure the magnetic fields around Venus. The radar and gravity data will provide clues to the level of crustal differentiation and tectonic activity. The magnetometer will determine the field variations accurately. Data from the combined experiments may constrain the dynamo mechanism; if so, a deeper understanding of both Venus and Earth will be gained.

  16. Kansei, surfaces and perception engineering

    Science.gov (United States)

    Rosen, B.-G.; Eriksson, L.; Bergman, M.

    2016-09-01

    The aesthetic and pleasing properties of a product are important and add significantly to the meaning and relevance of a product. Customer sensation and perception are largely about psychological factors. There has been a strong industrial and academic need and interest for methods and tools to quantify and link product properties to the human response but a lack of studies of the impact of surfaces. In this study, affective surface engineering is used to illustrate and model the link between customer expectations and perception to controllable product surface properties. The results highlight the use of the soft metrology concept for linking physical and human factors contributing to the perception of products. Examples of surface applications of the Kansei methodology are presented from sauna bath, health care, architectural and hygiene tissue application areas to illustrate, discuss and confirm the strength of the methodology. In the conclusions of the study, future research in soft metrology is proposed to allow understanding and modelling of product perception and sensations in combination with a development of the Kansei surface engineering methodology and software tools.

  17. Chemical Gel for Surface Decontamination

    International Nuclear Information System (INIS)

    Jung, Chong Hun; Moon, J. K.; Won, H. J.; Lee, K. W.; Kim, C. K.

    2010-01-01

    Many chemical decontamination processes operate by immersing components in aggressive chemical solutions. In these applications chemical decontamination technique produce large amounts of radioactive liquid waste. Therefore it is necessary to develop processes using chemical gels instead of chemical solutions, to avoid the well-known disadvantages of chemical decontamination techniques while retaining their high efficiency. Chemical gels decontamination process consists of applying the gel by spraying it onto the surface of large area components (floors, walls, etc) to be decontaminated. The gel adheres to any vertical or complex surface due to their thixotropic properties and operates by dissolving the radioactive deposit, along with a thin layer of the gel support, so that the radioactivity trapped at the surface can be removed. Important aspects of the gels are that small quantities can be used and they show thixitropic properties : liquid during spraying, and solid when stationary, allowing for strong adherence to surfaces. This work investigates the decontamination behaviors of organic-based chemical gel for SS 304 metallic surfaces contaminated with radioactive materials

  18. Surface electrical resistivity of insulators

    International Nuclear Information System (INIS)

    Senn, B. C.; Liesegang, J.

    1996-01-01

    A method is presented here for measuring surface charge decay, and theory has been developed so as to produce determinations of resistivity in the surface region of insulator films or wafers. This method incorporates the use of a coaxial cylindrical capacitor arrangement and an electrometer interfaced to a PC. The charge transport theory given here is based on Mott-Gurney diffusion, and allows easy interpretation of the experimental data, especially for the initial phase of surface charge decay. Resistivity measurements are presented for glass, mica, perspex and polyethylene, covering a range of 10 9 to 10 18 Ωm, as an illustration of the useful range of the instrument for static and antistatic materials, particularly in film or sheet form. Values for the surface charge diffusion constants of the materials are also presented. The charge transport theory has also been extended to allow the experimental and computational theoretical comparison of surface charge decay not only over the initial phase of charge decay, but also over longer times. The theoretical predictions show excellent agreement with experiment using the values for the diffusion constants referred to above

  19. EDITORIAL: Molecular switches at surfaces Molecular switches at surfaces

    Science.gov (United States)

    Weinelt, Martin; von Oppen, Felix

    2012-10-01

    In nature, molecules exploit interaction with their environment to realize complex functionalities on the nanometer length scale. Physical, chemical and/or biological specificity is frequently achieved by the switching of molecules between microscopically different states. Paradigmatic examples are the energy production in proton pumps of bacteria or the signal conversion in human vision, which rely on switching molecules between different configurations or conformations by external stimuli. The remarkable reproducibility and unparalleled fatigue resistance of these natural processes makes it highly desirable to emulate nature and develop artificial systems with molecular functionalities. A promising avenue towards this goal is to anchor the molecular switches at surfaces, offering new pathways to control their functional properties, to apply electrical contacts, or to integrate switches into larger systems. Anchoring at surfaces allows one to access the full range from individual molecular switches to self-assembled monolayers of well-defined geometry and to customize the coupling between molecules and substrate or between adsorbed molecules. Progress in this field requires both synthesis and preparation of appropriate molecular systems and control over suitable external stimuli, such as light, heat, or electrical currents. To optimize switching and generate function, it is essential to unravel the geometric structure, the electronic properties and the dynamic interactions of the molecular switches on surfaces. This special section, Molecular Switches at Surfaces, collects 17 contributions describing different aspects of this research field. They analyze elementary processes, both in single molecules and in ensembles of molecules, which involve molecular switching and concomitant changes of optical, electronic, or magnetic properties. Two topical reviews summarize the current status, including both challenges and achievements in the field of molecular switches on

  20. Surface flow measurements from drones

    Science.gov (United States)

    Tauro, Flavia; Porfiri, Maurizio; Grimaldi, Salvatore

    2016-09-01

    Drones are transforming the way we sense and interact with the environment. However, despite their increased capabilities, the use of drones in geophysical sciences usually focuses on image acquisition for generating high-resolution maps. Motivated by the increasing demand for innovative and high performance geophysical observational methodologies, we posit the integration of drone technology and optical sensing toward a quantitative characterization of surface flow phenomena. We demonstrate that a recreational drone can be used to yield accurate surface flow maps of sub-meter water bodies. Specifically, drone's vibrations do not hinder surface flow observations, and velocity measurements are in agreement with traditional techniques. This first instance of quantitative water flow sensing from a flying drone paves the way to novel observations of the environment.

  1. Surface EXAFS - A mathematical model

    International Nuclear Information System (INIS)

    Bateman, J.E.

    2002-01-01

    Extended X-ray absorption fine structure (EXAFS) studies are a powerful technique for studying the chemical environment of specific atoms in a molecular or solid matrix. The study of the surface layers of 'thick' materials introduces special problems due to the different escape depths of the various primary and secondary emission products which follow X-ray absorption. The processes are governed by the properties of the emitted fluorescent photons or electrons and of the material. Their interactions can easily destroy the linear relation between the detected signal and the absorption cross-section. Also affected are the probe depth within the surface and the background superimposed on the detected emission signal. A general mathematical model of the escape processes is developed which permits the optimisation of the detection modality (X-rays or electrons) and the experimental variables to suit the composition of any given surface under study

  2. Ion bombardment modification of surfaces

    International Nuclear Information System (INIS)

    Auciello, O.

    1984-01-01

    An historical overview of the main advances in the understanding of bombardment-induced surface topography is presented. The implantation and sputtering mechanisms which are relevant to ion bombardment modification of surfaces and consequent structural, electronic and compositional changes are described. Descriptions of plasma and ion-beam sputtering-induced film formation, primary ion-beam deposition, dual beam techniques, cluster of molecule ion-beam deposition, and modification of thin film properties by ion bombardment during deposition are presented. A detailed account is given of the analytical and computational modelling of topography from the viewpoint of first erosion theory. Finally, an account of the possible application and/or importance of textured surfaces in technologies and/or experimental techniques not considered in previous chapters is presented. refs.; figs.; tabs

  3. Surface stress-based biosensors.

    Science.gov (United States)

    Sang, Shengbo; Zhao, Yuan; Zhang, Wendong; Li, Pengwei; Hu, Jie; Li, Gang

    2014-01-15

    Surface stress-based biosensors, as one kind of label-free biosensors, have attracted lots of attention in the process of information gathering and measurement for the biological, chemical and medical application with the development of technology and society. This kind of biosensors offers many advantages such as short response time (less than milliseconds) and a typical sensitivity at nanogram, picoliter, femtojoule and attomolar level. Furthermore, it simplifies sample preparation and testing procedures. In this work, progress made towards the use of surface stress-based biosensors for achieving better performance is critically reviewed, including our recent achievement, the optimally circular membrane-based biosensors and biosensor array. The further scientific and technological challenges in this field are also summarized. Critical remark and future steps towards the ultimate surface stress-based biosensors are addressed. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Spherical Demons: Fast Surface Registration

    Science.gov (United States)

    Yeo, B.T. Thomas; Sabuncu, Mert; Vercauteren, Tom; Ayache, Nicholas; Fischl, Bruce; Golland, Polina

    2009-01-01

    We present the fast Spherical Demons algorithm for registering two spherical images. By exploiting spherical vector spline interpolation theory, we show that a large class of regularizers for the modified demons objective function can be efficiently implemented on the sphere using convolution. Based on the one parameter subgroups of diffeomorphisms, the resulting registration is diffeomorphic and fast – registration of two cortical mesh models with more than 100k nodes takes less than 5 minutes, comparable to the fastest surface registration algorithms. Moreover, the accuracy of our method compares favorably to the popular FreeSurfer registration algorithm. We validate the technique in two different settings: (1) parcellation in a set of in-vivo cortical surfaces and (2) Brodmann area localization in ex-vivo cortical surfaces. PMID:18979813

  5. Switchable Hydrophobic-Hydrophilic Surfaces

    CERN Document Server

    Bunker, B C; Huber, D L; Kent, M S; Kushmerick, J G; Lopez, G P; Manginell, R P; Méndez, S E; Yim, H

    2002-01-01

    Tethered films of poly n-isopropylacrylamide (PNIPAM) films have been developed as materials that can be used to switch the chemistry of a surface in response to thermal activation. In water, PNIPAM exhibits a thermally-activated phase transition that is accompanied by significant changes in polymer volume, water contact angle, and protein adsorption characteristics. New synthesis routes have been developed to prepare PNIPAM films via in-situ polymerization on self-assembled monolayers. Swelling transitions in tethered films have been characterized using a wide range of techniques including surface plasmon resonance, attenuated total reflectance infrared spectroscopy, interfacial force microscopy, neutron reflectivity, and theoretical modeling. PNIPAM films have been deployed in integrated microfluidic systems. Switchable PNIPAM films have been investigated for a range of fluidic applications including fluid pumping via surface energy switching and switchable protein traps for pre-concentrating and separating...

  6. Surface holograms for sensing application

    Science.gov (United States)

    Zawadzka, M.; Naydenova, I.

    2018-01-01

    Surface gratings with periodicity of 2 μm and amplitude in the range of 175 and 240 nm were fabricated in a plasticized polyvinylchloride doped with a metalloporphyrin (ZnTPP), via a single laser pulse holographic ablation process. The effect of the laser pulse energy on the profiles of the fabricated surface structure was investigated. The sensing capabilities of the fabricated diffractive structures towards amines (triethylamine, diethylamine) and pyridine vapours were then explored; the holographic structures were exposed to the analyte vapours and changes in the intensity of the diffracted light were monitored in real time at 473 nm. It was demonstrated that surface structures, fabricated in a polymer doped with a metalloporphyrin which acts as analyte receptor, have a potential in sensing application.

  7. Surface rights on Aboriginal lands

    International Nuclear Information System (INIS)

    McElhanney, W.L.

    1998-01-01

    Several issues regarding access and activity by petroleum industry on Aboriginal and Metis lands are discussed. Some alternative means by which both industry and Aboriginal groups can approach the matter of surface rights are presented. A historical account of how surface rights have been interpreted in the past was given. It was emphasized that the approach to surface rights compensation and negotiation for both aboriginal and industry parties must begin with adequate consultation. Rigid adherence to the usual past practice of geologically identifying locations, surveying and requesting a lease will no longer suffice. The aboriginal community must be consulted with as much lead time as possible, even assisted financially to identify traditional use areas that require protection, or cannot be disturbed, or require particular mitigation measures. Once this has been done, the operator can proceed to outline the scope of his project, detailing the timing, location, business and employment opportunities and other economic opportunities to the community. 21 refs

  8. Surface microhardening by ion implantation

    International Nuclear Information System (INIS)

    Singh, Amarjit

    1986-01-01

    The paper discusses the process and the underlying mechanism of surface microhardening by implanting suitable energetic ions in materials like 4145 steel, 304 stainless steel, aluminium and its 2024-T351 alloy. It has been observed that boron and nitrogen implantation in materials like 4145 steel and 304 stainless steel can produce a significant increase in surface hardness. Moreover the increase can be further enhanced with suitable overlay coatings such as aluminium (Al), Titanium (Ti) and carbon (C). The surface hardening due to implantation is attributed to precipitation hardening or the formation of stable/metastable phase or both. The effect of lithium implantation in aluminium and its alloy on microhardness with increasing ion dose and ion beam energy is also discussed. (author)

  9. Corrected body surface potential mapping.

    Science.gov (United States)

    Krenzke, Gerhard; Kindt, Carsten; Hetzer, Roland

    2007-02-01

    In the method for body surface potential mapping described here, the influence of thorax shape on measured ECG values is corrected. The distances of the ECG electrodes from the electrical heart midpoint are determined using a special device for ECG recording. These distances are used to correct the ECG values as if they had been measured on the surface of a sphere with a radius of 10 cm with its midpoint localized at the electrical heart midpoint. The equipotential lines of the electrical heart field are represented on the virtual surface of such a sphere. It is demonstrated that the character of a dipole field is better represented if the influence of the thorax shape is reduced. The site of the virtual reference electrode is also important for the dipole character of the representation of the electrical heart field.

  10. Nanobubble trouble on gold surfaces

    DEFF Research Database (Denmark)

    Holmberg, Maria; Kuhle, A.; Garnaes, J.

    2003-01-01

    When analyzing surfaces related to biosensors with in situ atomic force microscopy (AFM), the existence of nanobubbles called for our attention. The bubbles seem to form spontaneously when gold surfaces are immersed in clean water and are probably a general phenomenon at water-solid interfaces....... Besides from giving rise to undesired effects in, for example, biosensors, nanobubbles can also cause artifacts in AFM imaging. We have observed nanobubbles on unmodified gold surfaces, immersed in clean water, using standard silicon AFM probes. Nanobubbles can be made to disappear from contact mode AFM...... images and then to reappear by changing the scanning force. By combining contact mode AFM imaging and local force measurements, the interaction between the nanobubbles and the probe can be analyzed and give information about the characteristics of nanobubbles. A model of the forces between the AFM probe...

  11. The surface science of enzymes

    DEFF Research Database (Denmark)

    Rod, Thomas Holm; Nørskov, Jens Kehlet

    2002-01-01

    One of the largest challenges to science in the coming years is to find the relation between enzyme structure and function. Can we predict which reactions an enzyme catalyzes from knowledge of its structure-or from its amino acid sequence? Can we use that knowledge to modify enzyme function......? To solve these problems we must understand in some detail how enzymes interact with reactants from its surroundings. These interactions take place at the surface of the enzyme and the question of enzyme function can be viewed as the surface science of enzymes. In this article we discuss how to describe...... catalysis by enzymes, and in particular the analogies between enzyme catalyzed reactions and surface catalyzed reactions. We do this by discussing two concrete examples of reactions catalyzed both in nature (by enzymes) and in industrial reactors (by inorganic materials), and show that although analogies...

  12. Controllability of Surface Water Networks

    Science.gov (United States)

    Riasi, M. Sadegh; Yeghiazarian, Lilit

    2017-12-01

    To sustainably manage water resources, we must understand how to control complex networked systems. In this paper, we study surface water networks from the perspective of structural controllability, a concept that integrates classical control theory with graph-theoretic formalism. We present structural controllability theory and compute four metrics: full and target controllability, control centrality and control profile (FTCP) that collectively determine the structural boundaries of the system's control space. We use these metrics to answer the following questions: How does the structure of a surface water network affect its controllability? How to efficiently control a preselected subset of the network? Which nodes have the highest control power? What types of topological structures dominate controllability? Finally, we demonstrate the structural controllability theory in the analysis of a wide range of surface water networks, such as tributary, deltaic, and braided river systems.

  13. Bioinspired Surface Treatments for Improved Decontamination: Icephobic Surfaces

    Science.gov (United States)

    2017-06-26

    5 TABLES Table 1 — Contact angles ...fluorosilane to produce both texture and hydrophobic properties. [1, 2] The coating technology is reported to produce a water contact angle of greater than...160° with sliding angles ᝺° classifying the surface as superhydrophobic (water contact angles >150°). The durability of the material was previously

  14. Surface-complexation models for sorption onto heterogeneous surfaces

    International Nuclear Information System (INIS)

    Harvey, K.B.

    1997-10-01

    This report provides a description of the discrete-logK spectrum model, together with a description of its derivation, and of its place in the larger context of surface-complexation modelling. The tools necessary to apply the discrete-logK spectrum model are discussed, and background information appropriate to this discussion is supplied as appendices. (author)

  15. Surface chemistry of cellulose : from natural fibres to model surfaces

    NARCIS (Netherlands)

    Kontturi, E.J.

    2005-01-01

    The theme of the thesis was to link together the research aspects of cellulose occurring in nature (in natural wood fibres) and model surfaces of cellulose. Fundamental changes in cellulose (or fibre) during recycling of paper was a pragmatic aspect which was retained throughout the thesis with

  16. SURFACE ENERGY BALANCE OVER ORANGE ORCHARD USING SURFACE RENEWAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Salvatore Barbagallo

    2009-12-01

    Full Text Available Reliable estimation of surface sensible and latent heat flux is the most important process to appraise energy and mass exchange among atmosphere and biosphere. In this study the surface energy fluxes were measured over an irrigated orange orchard during 2005-2008 monitoring periods using a Surface Renewal- Energy Balance approach. The experimental area is located in a representative orchard growing area of eastern Sicily (Italy. The performance of Surface Renewal (SR analysis for estimating sensible heat flux (H was analysed and evaluated in terms of correlation with H fluxes from the eddy covariance (EC method. Study revealed that the mean available energy (RN- G and latent heat flux (LE were of about 300 W m-2 and 237 W m-2, respectively, during dry periods and unstable-case atmospheric conditions. The estimated crop coefficient Kc values for the orchard crop averaged close to 0.80, which is considerably higher than previous FAO studies that found the value to be 0.65 for citrus with 70% of ground cover. The intercepted photosynthetically active radiation (LI PAR by the crop was measured and relationships between LAI and crop coefficient (Kc were established.

  17. Surface modifications of dental implants.

    Science.gov (United States)

    Stanford, C M

    2008-06-01

    Dental implant surface technologies have been evolving rapidly to enhance a more rapid bone formation on their surface and hold a potential to increase the predictability of expedited implant therapy. While implant outcomes have become highly predictable, there are sites and conditions that result in elevated implant loss. This paper reviews the impact of macro-retentive features which includes approaches to surface oxide modification, thread design, press-fit and sintered-bead technologies to increase predictability of outcomes. Implant designs that lead to controlled lateral compression of the bone can improve primary stability as long as the stress does not exceed the localized yield strength of the cortical bone. Some implant designs have reduced crestal bone loss by use of multiple cutting threads that are closely spaced, smoothed on the tip but designed to create a hoop-stress stability of the implant as it is completely seated in the osteotomy. Following the placement of the implant, there is a predictable sequence of bone turnover and replacement at the interface that allows the newly formed bone to adapt to microscopic roughness on the implant surface, and on some surfaces, a nanotopography (<10(-9) m scale) that has been shown to preferably influence the formation of bone. Newly emerging studies show that bone cells are exquisitely sensitive to these topographical features and will upregulate the expression of bone related genes for new bone formation when grown on these surfaces. We live in an exciting time of rapid changes in the modalities we can offer patients for tooth replacement therapy. Given this, it is our responsibility to be critical when claims are made, incorporate into our practice what is proven and worthwhile, and to continue to support and provide the best patient care possible.

  18. Surface engineering by ion implantation

    International Nuclear Information System (INIS)

    Nielsen, Bjarne Roger

    1995-01-01

    Awidespread commercial applica tion iof particle accelerators is for ion implantation. Accelerator beams are used for ion implantation into metals, alloying a thin surface layer with foreign atoms to concentrations impossible to achieve by thermal processes, making for dramatic improvements in hardness and in resistance to wear and corrosion. Traditional hardening processes require high temperatures causing deformation; ion implantation on the other hand is a ''cold process'', treating the finished product. The ionimplanted layer is integrated in the substrate, avoiding the risk of cracking and delamination from normal coating processes. Surface properties may be ''engineered'' independently of those of the bulk material; the process does not use environmentally hazardous materials such as chromium in the surface coating. The typical implantation dose required for the optimum surface properties of metals is around 2 x 10 17 ion/cm 2 , a hundred times the typical doses for semiconductor processing. When surface areas of more than a few square centimetres have to be treated, the implanter must therefore be able to produce high beam currents (5 to 10 mA) to obtain an acceptable treatment time. Ion species used include nitrogen, boron, carbon, titanium, chromium and tantalum, and beam energies range from 50 to 200 keV. Since most components are three dimensional, it must be possible to rotate and tilt them in the beam, and control beam position over a large area. Examples of industrial applications are: - surface treatment of prostheses (hip and knee joints) to reduce wear of the moving parts, using biocompatible materials; - ion implantation into high speed ball bearings to protect against the aqueous corrosion in jet engines (important for service helicopters on oil rigs); - hardening of metal forming and cutting tools; - reduction of corrosive wear of plastic moulding tools, which are expensive to produce

  19. Surface rheology and interface stability.

    Energy Technology Data Exchange (ETDEWEB)

    Yaklin, Melissa A.; Cote, Raymond O.; Moffat, Harry K.; Grillet, Anne Mary; Walker, Lynn; Koehler, Timothy P.; Reichert, Matthew D. (Carnegie Mellon University, Pittsburgh, PA); Castaneda, Jaime N.; Mondy, Lisa Ann; Brooks, Carlton, F.

    2010-11-01

    We have developed a mature laboratory at Sandia to measure interfacial rheology, using a combination of home-built, commercially available, and customized commercial tools. An Interfacial Shear Rheometer (KSV ISR-400) was modified and the software improved to increase sensitivity and reliability. Another shear rheometer, a TA Instruments AR-G2, was equipped with a du Nouey ring, bicone geometry, and a double wall ring. These interfacial attachments were compared to each other and to the ISR. The best results with the AR-G2 were obtained with the du Nouey ring. A Micro-Interfacial Rheometer (MIR) was developed in house to obtain the much higher sensitivity given by a smaller probe. However, it was found to be difficult to apply this technique for highly elastic surfaces. Interfaces also exhibit dilatational rheology when the interface changes area, such as occurs when bubbles grow or shrink. To measure this rheological response we developed a Surface Dilatational Rheometer (SDR), in which changes in surface tension with surface area are measured during the oscillation of the volume of a pendant drop or bubble. All instruments were tested with various surfactant solutions to determine the limitations of each. In addition, foaming capability and foam stability were tested and compared with the rheology data. It was found that there was no clear correlation of surface rheology with foaming/defoaming with different types of surfactants, but, within a family of surfactants, rheology could predict the foam stability. Diffusion of surfactants to the interface and the behavior of polyelectrolytes were two subjects studied with the new equipment. Finally, surface rheological terms were added to a finite element Navier-Stokes solver and preliminary testing of the code completed. Recommendations for improved implementation were given. When completed we plan to use the computations to better interpret the experimental data and account for the effects of the underlying bulk

  20. Surface states in crystals with low-index surfaces

    International Nuclear Information System (INIS)

    Wang Hui-Ping; Tao Rui-Bao

    2015-01-01

    For most of the conventional crystals with low-index surfaces, the hopping between the nearest neighbor (1NN) crystal planes (CPs) is dominant and the ones from the nNN (2 ≤ n < ∞) CPs are relatively weak, considered as small perturbations. The recent theoretical analysis [1] has demonstrated the absence of surface states at the level of the hopping approximation between the 1NN CPs when the original infinite crystal has the geometric reflection symmetry (GRS) for each CP. Meanwhile, based on the perturbation theory, it has also been shown that small perturbations from the hopping between the nNN (2 ≤ n < ∞) CPs and surface relaxation have no impact on the above conclusion. However, for the crystals with strong intrinsic spin-orbit coupling (SOC), the dominant terms of intrinsic SOC associate with two 1NN bond hoppings. Thus SOC will significantly contribute the hoppings from the 1NN and/or 2NN CPs except the ones within each CP. Here, we will study the effect of the hopping between the 2NN CPs on the surface states in model crystals with three different type structures (Type I: “···–P–P–P–P–···”, Type II: “···–P–Q–P–Q–···” and Type III: “···–P=Q–P=Q–···” where P and Q indicate CPs and the signs “−” and “=” mark the distance between the 1NN CPs). In terms of analytical and numerical calculations, we study the behavior of surface states in three types after the symmetric/asymmetric hopping from the 2NN CPs is added. We analytically prove that the symmetric hopping from the 2NN CPs cannot induce surface states in Type I when each CP has only one electron mode. The numerical calculations also provide strong support for the conclusion, even up to 5NN. However, in general, the coupling from the 2NN CPs (symmetric and asymmetric) is favorable to generate surface states except Type I with single electron mode only. (paper)

  1. Structure of the moon's surface

    CERN Document Server

    Fielder, Gilbert

    1961-01-01

    Structure of the Moon's Surface aims to assemble and marshal relevant matter, and to produce a largely unprejudiced text which brings lunar studies up to date and stresses the importance of certain features of the Moon which have frequently been disregarded in the past, largely because of lack of knowledge about them. The book contains 14 chapters organized into two parts. Part I reviews and summarizes important physical problems. These include the liberations of the moon; height determinations of points of the moon's surface; the figure of the moon; and the moon's temperature and atmosphere.

  2. Coherent states and rational surfaces

    International Nuclear Information System (INIS)

    Brody, Dorje C; Graefe, Eva-Maria

    2010-01-01

    The state spaces of generalized coherent states associated with special unitary groups are shown to form rational curves and surfaces in the space of pure states. These curves and surfaces are generated by the various Veronese embeddings of the underlying state space into higher dimensional state spaces. This construction is applied to the parameterization of generalized coherent states, which is useful for practical calculations, and provides an elementary combinatorial approach to the geometry of the coherent state space. The results are extended to Hilbert spaces with indefinite inner products, leading to the introduction of a new kind of generalized coherent states.

  3. [Inelastic electron scattering from surfaces

    International Nuclear Information System (INIS)

    1993-01-01

    This program uses ab-initio and multiple scattering to study surface dynamical processes; high-resolution electron-energy loss spectroscopy is used in particular. Off-specular excitation cross sections are much larger if electron energies are in the LEED range (50--300 eV). The analyses have been extended to surfaces of ordered alloys. Phonon eigenvectors and eigenfrequencies were used as inputs to electron-energy-loss multiple scattering cross section calculations. Work on low-energy electron and positron holography is mentioned

  4. Interactive Design of Developable Surfaces

    KAUST Repository

    Tang, Chengcheng

    2016-01-15

    We present a new approach to geometric modeling with developable surfaces and the design of curved-creased origami. We represent developables as splines and express the nonlinear conditions relating to developability and curved folds as quadratic equations. This allows us to utilize a constraint solver, which may be described as energy-guided projection onto the constraint manifold, and which is fast enough for interactive modeling. Further, a combined primal-dual surface representation enables us to robustly and quickly solve approximation problems.

  5. Growth morphologies of crystal surfaces

    Science.gov (United States)

    Xiao, Rong-Fu; Alexander, J. Iwan D.; Rosenberger, Franz

    1991-03-01

    We have expanded our earlier Monte Carlo model [Phys. Rev. A 38, 2447 (1988); J. Crystal Growth 100, 313 (1990)] to three dimensions and included reevaporation after accommodation and growth on dislocation-induced steps. We found again that, for a given set of growth parameters, the critical size, beyond which a crystal cannot retain its macroscopically faceted shape, scales linearly with the mean free path in the vapor. However, the three-dimensional (3D) the systems show increased shape stability compared to corresponding 2D cases. Extrapolation of the model results to mean-free-path conditions used in morphological stability experiments leads to order-of-magnitude agreement of the predicted critical size with experimental findings. The stability region for macroscopically smooth (faceted) surfaces in the parameter space of temperature and supersaturation depends on both the surface and bulk diffusion. While surface diffusion is seen to smooth the growth morphology on the scale of the surface diffusion length, bulk diffusion is always destabilizing. The atomic surface roughness increases with increase in growth temperature and supersaturation. That is, the tendency of surface kinetics anisotropies to stabilize the growth shape is reduced through thermal and kinetic roughening. It is also found that the solid-on-solid assumption, which can be advantageously used at low temperatures and supersaturations, is insufficient to describe the growth dynamics of atomically rough interfaces where bulk diffusion governs the process. For surfaces with an emerging screw dislocation, we find that the spiral growth mechanism dominates at low temperatures and supersaturations. The polygonization of a growth spiral decreases with increasing temperature or supersaturation. When the mean free path in the nutrient is comparable to the lattice constant, the combined effect of bulk and surface diffusion reduces the terrace width of a growth spiral in its center region. At elevated

  6. Interactive Design of Developable Surfaces

    KAUST Repository

    Tang, Chengcheng; Bo, Pengbo; Wallner, Johannes; Pottmann, Helmut

    2016-01-01

    We present a new approach to geometric modeling with developable surfaces and the design of curved-creased origami. We represent developables as splines and express the nonlinear conditions relating to developability and curved folds as quadratic equations. This allows us to utilize a constraint solver, which may be described as energy-guided projection onto the constraint manifold, and which is fast enough for interactive modeling. Further, a combined primal-dual surface representation enables us to robustly and quickly solve approximation problems.

  7. Cold atoms close to surfaces

    DEFF Research Database (Denmark)

    Krüger, Peter; Wildermuth, Stephan; Hofferberth, Sebastian

    2005-01-01

    Microscopic atom optical devices integrated on atom chips allow to precisely control and manipulate ultra-cold (T atoms and Bose-Einstein condensates (BECs) close to surfaces. The relevant energy scale of a BEC is extremely small (down to ... be utilized as a sensor for variations of the potential energy of the atoms close to the surface. Here we describe how to use trapped atoms as a measurement device and analyze the performance and flexibility of the field sensor. We demonstrate microscopic magnetic imaging with simultaneous high spatial...

  8. Collaboration Meets Interactive Surfaces (CMIS)

    DEFF Research Database (Denmark)

    Anslow, Craig; Campos, Pedro; Grisoni, Laurent

    2015-01-01

    This workshop proposes to bring together researchers who are interested in improving collaborative experiences through the combination of multiple interaction surfaces with diverse sizes and formats, ranging from large-scale walls, to tables, mobiles, and wearables. The opportunities for innovation...... exist, but the ITS, CHI, CSCW, and other HCI communities have not yet thoroughly addressed the problem of bringing effective collaboration activities together using multiple interactive surfaces, especially in complex work domains. Of particular interest is the potential synergy that one can obtain...

  9. Corrosion principles and surface modification

    International Nuclear Information System (INIS)

    Kruger, J.

    1982-01-01

    This chapter examines the important strategies provided by the newer ideas of corrosion science and engineering that surface modification techniques must utilize to help prevent corrosion, especially the most damaging kind of aqueous corrosion, localized corrosion. Provides a brief introduction to the principles underlying the phenomenon of corrosion in order to use them to discuss surface modification strategies to combat corrosion. Discusses the electrochemistry of corrosion; the thermodynamics of corrosion; the kinetics of corrosion; thermodynamic strategies; and kinetic strategies (formation of more protective passive films; resistance to breakdown; ductility; repassivation)

  10. Bianchi surfaces: integrability in an arbitrary parametrization

    International Nuclear Information System (INIS)

    Nieszporski, Maciej; Sym, Antoni

    2009-01-01

    We discuss integrability of normal field equations of arbitrarily parametrized Bianchi surfaces. A geometric definition of the Bianchi surfaces is presented as well as the Baecklund transformation for the normal field equations in an arbitrarily chosen surface parametrization.

  11. Direct detection of near-surface faults by migration of back-scattered surface waves

    KAUST Repository

    Yu, Han; Guo, Bowen; Hanafy, Sherif; Lin, Fan-Chi; Schuster, Gerard T.

    2014-01-01

    We show that diffraction stack migration can be used to estimate the distribution of near-surface faults. The assumption is that near-surface faults generate detectable back-scattered surface waves from impinging surface waves. The processing steps

  12. Surface Transportation Security Priority Assessment

    Science.gov (United States)

    2010-03-01

    intercity buses), and pipelines, and related infrastructure (including roads and highways), that are within the territory of the United States...Modernizing the information technology infrastructure used to vet the identity of travelers and transportation workers  Using terrorist databases to...examination of persons travelling , surface transportation modes tend to operate in a much more open environment, making it difficult to screen workers

  13. Surface-modified electrodes (SME)

    NARCIS (Netherlands)

    Schreurs, J.P.G.M.; Barendrecht, E.

    1984-01-01

    This review deals with the literature (covered up to August 1983), the characterization and the applications of Surface-Modified Electrodes (SME). As a special class of SME's, the Enzyme-Modified Electrode (EME) is introduced. Three types of modification procedures are distinguished; i.e. covalent

  14. Supermanifolds and super Riemann surfaces

    International Nuclear Information System (INIS)

    Rabin, J.M.

    1986-09-01

    The theory of super Riemann surfaces is rigorously developed using Rogers' theory of supermanifolds. The global structures of super Teichmueller space and super moduli space are determined. The super modular group is shown to be precisely the ordinary modular group. Super moduli space is shown to be the gauge-fixing slice for the fermionic string path integral

  15. Anisotropic dehydration of hydrogel surfaces.

    Science.gov (United States)

    Kaklamani, Georgia; Cheneler, David; Grover, Liam M; Adams, Michael J; Anastasiadis, Spiros H; Bowen, James

    2017-12-01

    Efforts to develop tissue-engineered skin for regenerative medicine have explored natural, synthetic, and hybrid hydrogels. The creation of a bilayer material, with the stratification exhibited by native skin, is a complex problem. The mechanically robust, waterproof epidermis presents the stratum corneum at the tissue/air interface, which confers many of these protective properties. In this work, we explore the effect of high temperatures on alginate hydrogels, which are widely employed for tissue engineering due to their excellent mechanical properties and cellular compatibility. In particular, we investigate the rapid dehydration of the hydrogel surface which occurs following local exposure to heated surfaces with temperatures in the range 100-200 °C. We report the creation of a mechanically strengthened hydrogel surface, with improved puncture resistance and increased coefficient of friction, compared to an unheated surface. The use of a mechanical restraint during heating promoted differences in the rate of mass loss; the rate of temperature increase within the hydrogel, in the presence and absence of restraint, is simulated and discussed. It is hoped that the results will be of use in the development of processes suitable for preparing skin-like analogues; application areas could include wound healing and skin restoration.

  16. Surface meshing with curvature convergence

    KAUST Repository

    Li, Huibin; Zeng, Wei; Morvan, Jean-Marie; Chen, Liming; Gu, Xianfengdavid

    2014-01-01

    Surface meshing plays a fundamental role in graphics and visualization. Many geometric processing tasks involve solving geometric PDEs on meshes. The numerical stability, convergence rates and approximation errors are largely determined by the mesh qualities. In practice, Delaunay refinement algorithms offer satisfactory solutions to high quality mesh generations. The theoretical proofs for volume based and surface based Delaunay refinement algorithms have been established, but those for conformal parameterization based ones remain wide open. This work focuses on the curvature measure convergence for the conformal parameterization based Delaunay refinement algorithms. Given a metric surface, the proposed approach triangulates its conformal uniformization domain by the planar Delaunay refinement algorithms, and produces a high quality mesh. We give explicit estimates for the Hausdorff distance, the normal deviation, and the differences in curvature measures between the surface and the mesh. In contrast to the conventional results based on volumetric Delaunay refinement, our stronger estimates are independent of the mesh structure and directly guarantee the convergence of curvature measures. Meanwhile, our result on Gaussian curvature measure is intrinsic to the Riemannian metric and independent of the embedding. In practice, our meshing algorithm is much easier to implement and much more efficient. The experimental results verified our theoretical results and demonstrated the efficiency of the meshing algorithm. © 2014 IEEE.

  17. Empirical isotropic chemical shift surfaces

    International Nuclear Information System (INIS)

    Czinki, Eszter; Csaszar, Attila G.

    2007-01-01

    A list of proteins is given for which spatial structures, with a resolution better than 2.5 A, are known from entries in the Protein Data Bank (PDB) and isotropic chemical shift (ICS) values are known from the RefDB database related to the Biological Magnetic Resonance Bank (BMRB) database. The structures chosen provide, with unknown uncertainties, dihedral angles φ and ψ characterizing the backbone structure of the residues. The joint use of experimental ICSs of the same residues within the proteins, again with mostly unknown uncertainties, and ab initio ICS(φ,ψ) surfaces obtained for the model peptides For-(l-Ala) n -NH 2 , with n = 1, 3, and 5, resulted in so-called empirical ICS(φ,ψ) surfaces for all major nuclei of the 20 naturally occurring α-amino acids. Out of the many empirical surfaces determined, it is the 13C α ICS(φ,ψ) surface which seems to be most promising for identifying major secondary structure types, α-helix, β-strand, left-handed helix (α D ), and polyproline-II. Detailed tests suggest that Ala is a good model for many naturally occurring α-amino acids. Two-dimensional empirical 13C α - 1 H α ICS(φ,ψ) correlation plots, obtained so far only from computations on small peptide models, suggest the utility of the experimental information contained therein and thus they should provide useful constraints for structure determinations of proteins

  18. Surface meshing with curvature convergence

    KAUST Repository

    Li, Huibin

    2014-06-01

    Surface meshing plays a fundamental role in graphics and visualization. Many geometric processing tasks involve solving geometric PDEs on meshes. The numerical stability, convergence rates and approximation errors are largely determined by the mesh qualities. In practice, Delaunay refinement algorithms offer satisfactory solutions to high quality mesh generations. The theoretical proofs for volume based and surface based Delaunay refinement algorithms have been established, but those for conformal parameterization based ones remain wide open. This work focuses on the curvature measure convergence for the conformal parameterization based Delaunay refinement algorithms. Given a metric surface, the proposed approach triangulates its conformal uniformization domain by the planar Delaunay refinement algorithms, and produces a high quality mesh. We give explicit estimates for the Hausdorff distance, the normal deviation, and the differences in curvature measures between the surface and the mesh. In contrast to the conventional results based on volumetric Delaunay refinement, our stronger estimates are independent of the mesh structure and directly guarantee the convergence of curvature measures. Meanwhile, our result on Gaussian curvature measure is intrinsic to the Riemannian metric and independent of the embedding. In practice, our meshing algorithm is much easier to implement and much more efficient. The experimental results verified our theoretical results and demonstrated the efficiency of the meshing algorithm. © 2014 IEEE.

  19. EUROMET SUPPLEMENTARY COMPARISON - SURFACE TEXTURE

    DEFF Research Database (Denmark)

    Koenders, L.; Andreasen, Jan Lasson; De Chiffre, Leonardo

    At the length meeting in Prague in Oct. 1999 a new comparison was suggested on surface texture. The last comparison on this field was finished in 1989. In the meantime the instrumentation, the standards and the written standards have been improved including some software filters. The pilot labora...

  20. Physical characteristics of satellite surfaces

    International Nuclear Information System (INIS)

    Veverka, J.; Thomas, P.; Johnson, T.V.; Matson, D.; Housen, K.

    1986-01-01

    Both exogenic and endogenic effects have been proposed to explain the major observed characteristics of satellite surfaces. The current view is that the basic properties of most surfaces result from the intrinsic composition of a body and its geologic history. Exogenic effects have, however, played a role in modifying the appearance of nearly all surfaces. The most important exogenic effect is impact cratering, one manifestation of which is the production of micrometeoroid gardened regoliths on airless bodies. On large, silicate bodies the micrometeoroid bombardment can produce an optically mature, dark agglutinate-rich soil; the nature of regoliths on predominantly icy satellites remains uncertain. Direct accumulation of infalling material does not appear to play a major role in modifying most surfaces. Solar wind radiation effects have not altered greatly the optical properties of solar system objects; magnetospheric charged particles may have modified the optical properties of some outer planet satellites (e.g., sulfur ion bombardment in the case of some of the satellites of Jupiter). Other effects, such as aeolian and liquid/solid chemical weathering, may be important on satellites with atmospheres like Titan and Triton