1,815 research outputs found
RoomâTemperature Transport Properties of Graphene with Defects Derived from OxoâGraphene
In recent years, graphene oxide has been considered as a soluble precursor of graphene for electronic applications. However, the performance lags behind that of graphene due to lattice defects. Here, the relation between the density of defects in the range of 0.2â% and 1.5â% and the transport properties is quantitatively studied. Therefore, the related flakes of monolayers of graphene were prepared from oxoâfunctionalized graphene (oxoâG). The morphologic structure of oxoâG was imaged by atomic force microscopy (AFM) and scanning tunneling microscopy (STM). Fieldâeffect mobility values were determined to range between 0.3â
cm2âVâ1âsâ1 and 33.2â
cm2âVâ1âsâ1, which were inversely proportional to the density of defects. These results provide the first quantitative description of the density of defects and transport properties, which plays an important role for potential applications
Text Communication as Interplay between Text Processing and Text Producing
ZunĂ€chst wird das Thema in den Rahmen der Erziehungswissenschaft historisch eingeordnet. Sodann werden Text- verarbeiten und Textproduzieren als aufeinander und auf Wissen bezogene Prozesse theoretisch begrĂŒndet und auf dem Hintergrund eines Experiments nĂ€her expliziert. Im letzten Abschnitt werden die theoretischen Erörterungen aufgegriffen und zu anderen Forschungsgebieten der Erziehungswissenschaft (Bildungsgeschichte, Curriculumdiskussion...) in Beziehung gesetzt. (DIPF/Orig.
Research on Text Production
Es wird versucht, die Entwicklung der Textproduktionsforschung in den beiden letzten Jahrzehnten zu skizzieren. Die geschieht in Form eines kommentierten LiteraturĂŒberblicks, der zunĂ€chst die entscheidenden Bezugsmodelle der amerikanischen Textproduktionsforschung vorstellt, um im folgenden auf deren Aufnahme und Weiterentwicklung in Deutschland einzugehen. Dabei werden die zugrundeliegenden Forschungskonzeptionen in den Blick genommen, um aus dieser Perspektive disziplinbedingte Defizite und Desiderate zukĂŒnftiger Forschung aufzuzeigen. (DIPF/Orig.
IL-1 receptor antagonist production by isolated mononuclear cells is a better indicator of bioincompatibility of hemodialysis membranes than that by stimulated whole blood
The use of perlite as an adsorbent
The adsorptive properties of perlite, an expanded volcanic glass, have been studied. Several activating treatments were investigated, air oxidation it 400 degrees Centigrade appears to be the best, The adsorption of the basic dye emethylene blue yields a saturation valve of 50 milligrams per gram of perlite. The acid dye cotton blue showed no measurable adsorption. A maximum adsorption of 15 millimoles of acetic acid and one milligram of iodine were found in aqueous solution. A high value of 1.33 milligrams of iodine per gram of perlite were found in methyl alcohol solutions. The surface area of perlite appears to be rather low, The material does not seem suitable for use as avcommercial adsorbant
CUP: Comprehensive User-Space Protection for C/C++
Memory corruption vulnerabilities in C/C++ applications enable attackers to
execute code, change data, and leak information. Current memory sanitizers do
no provide comprehensive coverage of a program's data. In particular, existing
tools focus primarily on heap allocations with limited support for stack
allocations and globals. Additionally, existing tools focus on the main
executable with limited support for system libraries. Further, they suffer from
both false positives and false negatives.
We present Comprehensive User-Space Protection for C/C++, CUP, an LLVM
sanitizer that provides complete spatial and probabilistic temporal memory
safety for C/C++ program on 64-bit architectures (with a prototype
implementation for x86_64). CUP uses a hybrid metadata scheme that supports all
program data including globals, heap, or stack and maintains the ABI. Compared
to existing approaches with the NIST Juliet test suite, CUP reduces false
negatives by 10x (0.1%) compared to the state of the art LLVM sanitizers, and
produces no false positives. CUP instruments all user-space code, including
libc and other system libraries, removing them from the trusted code base
Theory of the Eigler-swith
We suggest a simple model to describe the reversible field-induced transfer
of a single Xe-atom in a scanning tunneling microscope, --- the Eigler-switch.
The inelasticly tunneling electrons give rise to fluctuating forces on and
damping of the Xe-atom resulting in an effective current dependent temperature.
The rate of transfer is controlled by the well-known Arrhenius law with this
effective temperature. The directionality of atom transfer is discussed, and
the importance of use of non-equlibrium-formalism for the electronic
environment is emphasized. The theory constitutes a formal derivation and
generalization of the so-called Desorption Induced by Multiple Electron
Transitions (DIMET) point of view.Comment: 13 pages (including 2 figures in separate LaTeX-files with
ps-\specials), REVTEX 3.
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