Search results for "interface"
showing 10 items of 2139 documents
Phase transitions in adsorbed layers formed on crystals of square and rectangular surface lattice
2000
Abstract This article gives a survey of phase transitions in adsorbed films on well defined surfaces of square and rectangular symmetry of the lattice. The discussion concentrates on the effects of periodic changes of the adsorbate–substrate potential on the structure and thermodynamic properties of adsorbed films. Different theoretical approaches are briefly reviewed, with an emphasis on those which explicitly take into account final corrugation of the surface potential. Several aspects of statistical mechanical description of phase transitions in surface layers, such as order–disorder, melting, commensurate–incommensurate transitions in monolayer films as well as transitions connected wit…
Growth of large liquid crystalline domains of phospholipids at air-water interfaces
1990
Abstract The fusion of condensed phase domains in a fluid environment in monolayers is studied. A system of electrodes permits the non-invasive and predetermined movement of single domains while the film is observed by fluorescence microscopy. Two domains fuse when they are brought into contact with special positions of their borderlines. The experiment yields information about the molecular structure of the domains and allows us to fabricate very large domains. The equilibrium size is estimated and verified.
Energy and spatial distribution of traps in SiO2/Al 2O3 nMOSFETs
2006
The energy and spatial profiling of the interface and near-interface traps in n-channel MOSFETs with SiO2/Al2O3 gate dielectrics is investigated by charge-pumping (CP) measurements. By increasing the amplitude as well as lowering the frequency of the gate pulse, an increase of the charge recombined per cycle was observed, and it was explained by the contributions of additional traps located higher in energy and deeper in position at the SiO2/Al2O3 interface. In addition, CP currents, acquired after different constant voltage stress, have been used to investigate the trap generation in this dielectric stack. © 2006 IEEE.
Experimental studies on the detachment of multi-walled carbon nanotubes by a mobile liquid interface
2017
International audience; Retention and detachment of colloidal particles from surfaces is often considered only in terms of spontaneous chemical dispersion when the surface is already fully submerged. Nevertheless, interfacial processes, where the particles are caught on a mobile liquid contact line by capillary effects are ubiquitous. Theoretical description of such interfacial processes exist for spherical microcolloids, while for anisotropic shapes the literature is limited. Arc-discharge synthesized multiwalled carbon nanotube (MWNT) material contains besides the very anisotropic tubes also irregular amorphous carbon particles (ACP) that both are strongly hydrophobic. As a water–air–soli…
First characterization of Gamkonora gas emission, North Maluku, East Indonesia
2020
Gamkonora is an active volcano capable of intense manifestations that regularly forced thousands of inhabitants to flee their villages. The most extreme eruption, in 1673, was a VEI 5 event that induced pitch-dark environment over the region. Paradoxically, little is known about Gamkonora volcano and here we present the first gas measurement results obtained in September 2018 using a MultiGAS and a scanning DOAS. Results highlight a relatively small but magmatic gas with a CO2/ST of 3.5, in the range of high-temperature gas emissions from Indonesian volcanoes and H2O/SO2, CO2/SO2, H2S/SO2, and H2/SO2 ratios of 135, 5.6, 0.6, and 0.2, respectively. The daily gas emission budget corresponds t…
A Language and Platform Independent Co-Simulation Framework Based on the Functional Mock-Up Interface
2019
The main goal of the Functional Mock-up Interface (FMI) standard is to allow the sharing of simulation models across tools. To accomplish this, FMI relies on a combination of XML-files and compiled C-code packaged in a zip archive. This archive is called a Functional Mock-up Unit (FMU). In theory, an FMU can support multiple platforms, but not necessarily in practice. Furthermore, software libraries for interacting with FMUs may not be available in a particular language or platform. Another issue is related to the protection of intellectual property (IP). While an FMU is free to only provide the C-code in its binary form, other resources within the FMU may be unprotected. Distributing model…
A framework for behavior-based detection of user substitution in a mobile context
2007
Personal mobile devices, such as mobile phones, smartphones, and communicators can be easily lost or stolen. Due to the functional abilities of these devices, their use by unintended persons may result in severe security breaches concerning private or corporate data and services. Organizations develop their security policy and employ preventive techniques to combat unauthorized use. Current solutions, however, are still breakable and there is a strong need for means to detect user substitution when it happens. A crucial issue in designing such means is to define the measures to be monitored. In this paper, a structured conceptual framework for mobile-user substitution detection is proposed.…
Expectations for supporting student engagement with learning analytics : an academic path perspective
2021
There has been a growing interest in higher education to explore how learning analytics (LA) could be used to support student engagement. Providing actionable feedback with LA for students is an emerging area of research. Previous studies have commonly focused on course-level aspects of supporting engagement with LA, but students' perspectives have received limited attention. This study analyzed pre-service teachers’ needs and expectations for LA to support student engagement on the academic path level, which means observing the continuum of study periods and academic years. Qualitative content analysis was conducted for video-recorded student small-group conversations to analyze in-depth h…
Natural payload delivery of the doxorubicin anticancer drug from boron nitride oxide nanosheets
2019
International audience; We studied the behavior of doxorubicin (DOX; an anticancer drug) molecules loaded on a boron nitride oxide nanosheet (BNO-NS) using the density functional theory (DFT), time-dependent density functional theory (TDDFT), and molecular dynamic (MD) simulation methods. We found that DOX molecules in pi-pi or covalent interaction with BNO-NS preserve their optical properties in water. Moreover, the BNO-NS vector allowed stabilizing the DOX molecules on a cellular membrane contrary to isolated DOX that randomly moved in the solvent box without any interaction with the cell membrane. From these results, we conclude that hydrophilic BNO-NS represents a good candidate for DOX…
Dynamics of molybdenum nano structure formation on the TiO2(110) surface: A kinetic Monte Carlo approach
2006
Abstract The rutile TiO 2 (1 1 0) surface is a highly anisotropic surface exhibiting “channels” delimited by oxygen rows. In previous experimental and theoretical DFT works we could identify the molybdenum adsorption sites. They are located inside the channels. Moreover, experimental studies have shown that during subsequent annealing after deposition, special molybdenum nano structures can be formed, especially two monolayer high pyramidal chains of atoms. In order to better understand the dynamics of nano structure formation, we present a kinetic Monte Carlo study on diffusion and adsorption of molybdenum atoms on a TiO 2 (1 1 0) surface. A quasi one-dimensional lattice gas model has been…