1,720,969 research outputs found
Interaction of group III and IV metals with Si(100) surface in temperature range from 20 to 800K
No full text1 Title: Interaction of group III and IV metals with Si(100) surface in temperature range from 20 to 800 K Author: Martin Setvín Department: Departement of Surface and Plasma Science Supervisor of the doctoral thesis: Doc. RNDr. Ivan Ošt'ádal CSc. Abstract: Interaction of group III and IV metals with Si(100) surface was studied by STM (Scanning Tunneling Microscopy) and AFM (Atomic Force Microscopy) in temperature range from 20 to 800 K. Adsorption and hopping of single metal adatoms on Si(100)-c(4×2) reconstruction can be observed by STM at low temperatures. Activation energies and frequency prefactors for hopping of single indium atoms were measured by two meth- ods - direct STM measurement at low temperature and Kinetic Monte Carlo simulations of layer growth at room temperature. Group III and IV atoms self-assemble into single atom wide chains on Si(100) surface at about room temperature. Atomic and electronic structure of the chains was investi- gated by means of STM and dynamic non-contact AFM. Keywords: Si(100), STM, AFM, adsorption, diffusio
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Interakce kovů II. a IV. skupiny s povrchem SI(100) rozmezí teplot od 20 do 800KI
Full text link1 Title: Interaction of group III and IV metals with Si(100) surface in temperature range from 20 to 800 K Author: Martin Setvín Department: Departement of Surface and Plasma Science Supervisor of the doctoral thesis: Doc. RNDr. Ivan Ošt'ádal CSc. Abstract: Interaction of group III and IV metals with Si(100) surface was studied by STM (Scanning Tunneling Microscopy) and AFM (Atomic Force Microscopy) in temperature range from 20 to 800 K. Adsorption and hopping of single metal adatoms on Si(100)-c(4×2) reconstruction can be observed by STM at low temperatures. Activation energies and frequency prefactors for hopping of single indium atoms were measured by two meth- ods - direct STM measurement at low temperature and Kinetic Monte Carlo simulations of layer growth at room temperature. Group III and IV atoms self-assemble into single atom wide chains on Si(100) surface at about room temperature. Atomic and electronic structure of the chains was investi- gated by means of STM and dynamic non-contact AFM. Keywords: Si(100), STM, AFM, adsorption, diffusion1 Název práce: Interakce kovů III. a IV. skupiny s povrchem Si(100) v rozmezí teplot od 20 do 800 K Autor: Martin Setvín Katedra: Katedra fyziky povrchů a plazmatu Vedoucí doktorské práce: Doc. RNDr. Ivan Ošt'ádal CSc. Abstrakt: Interakce kovů III. a IV. skupiny s povrchem Si(100) v rozmezí teplot od 20 do 800 K byla studována pomocí rastrovací tunelové mikroskopie (STM) a mikroskopie atomárních sil (AFM). Adsorpci a přeskoky jednotlivých kovových atomů na povrchu Si(100)-c(4×2) lze sledovat pomocí STM za snížených teplot. Pomocí dvou metod byly určeny aktivačí energie a frekvenční prefaktory pro přeskoky jednotlivých indiových atomů - přímým STM měřením za nízké teploty a pomocí kinetických Monte Carlo simulací růstového pro- cesu za pokojové teploty. Kovy III. a IV. kupiny se v blízkosti pokojové teploty samouspořádávají do řetízků, které jsou pouze jeden atom široké. Atomární a elektronová struktura řetízků byla zkoumána pomocí STM a dynamického nekontaktního AFM. Klíčová slova: Si(100), STM, AFM, adsorpce, difúzeKatedra fyziky povrchů a plazmatuDepartment of Surface and Plasma ScienceFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Study of molecular structures on solid surfaces with scanning probe microscopy
Full text linkSimultánní skenovací tunelová mikroskopie (STM) a bezkontaktní mikroskopie atomárních sil (ncAFM) představují špičkové experimentální nástroje pro zkoumání a charakterizaci hmoty na úrovni jednotlivých atomů a molekul. Tato práce se tematicky soustředí na výzkum pomocí rastrovacích mikroskopů. Její důležitá část byla věnována modernizaci starého STM mikroskopu na novou nízkoteplotní STM/ncAFM sestavu v laboratořích skupiny Nanosurf při Fyzikálním ústavu AVČR. Modernizace zahrnovala návrh několika součástí nové sestavy (Load-lock komoru, úschovnu vzorků) a dalších funkčních komponent (Dual Sample plates, držák na FIB řezání SPM senzorů) usnadňujících experimentální výzkum v rámci skupiny Nanosurf.On-surface chemistry to form low dimensional organic materials with exotic properties is an advanced field in nanoscience, as it opens many possibilities for understanding low-dimensional physics and chemistry. The first part of the thesis is dedicated to the upgrade of an old variable-temperature STM microscope to a new low-temperature STM/ncAFM setup in the laboratories of the Nanosurf group at Institute of Physics, CAS. The rest of the thesis focuses on four research projects investigating molecular systems on metallic substrates by STM and ncAFM, primarily products of various on-surface reactions
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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