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On the stability and growth of single myelin figures  [PDF]
Ling-Nan Zou,Sidney R. Nagel
Physics , 2005, DOI: 10.1103/PhysRevLett.96.138301
Abstract: Myelin figures are long thin cylindrical structures that typically grow as a dense tangle when water is added to the concentrated lamellar phase of certain surfactants. We show that, starting from a well-ordered initial state, single myelin figures can be produced in isolation thus allowing a detailed study of their growth and stability. These structures grow with their base at the exposed edges of bilayer stacks from which material is transported into the myelin. Myelins only form and grow in the presence of a driving stress; when the stress is removed, the myelins retract.
Frictional figures of merit for single layered nanostructures  [PDF]
S. Cahangirov,C. Ataca,M. Topsakal,H. Sahin,S. Ciraci
Physics , 2014, DOI: 10.1103/PhysRevLett.108.126103
Abstract: We determined frictional figures of merit for a pair of layered honeycomb nanostructures, such as graphane, fluorographene, MoS$_2$ and WO$_2$ moving over each other, by carrying out ab-initio calculations of interlayer interaction under constant loading force. Using Prandtl-Tomlinson model we derived critical stiffness required to avoid stick-slip behavior. We showed that these layered structures have low critical stiffness even under high loading forces due to their charged surfaces repelling each other. The intrinsic stiffness of these materials exceed critical stiffness and thereby avoid the stick-slip regime and attain nearly dissipationless continuous sliding. Remarkably, tungsten dioxide displays much better performance relative to others and heralds a potential superlubricant. The absence of mechanical instabilities leading to conservative lateral forces is also confirmed directly by the simulations of sliding layers.
Preparation of pure and mixed polarization qubits and the direct measurement of figures of merit  [PDF]
R. B. A. Adamson,L. K. Shalm,A. M. Steinberg
Physics , 2006, DOI: 10.1103/PhysRevA.75.012104
Abstract: Non-classical joint measurements can hugely improve the efficiency with which certain figures of merit of quantum systems are measured. We use such a measurement to determine a particular figure of merit, the purity, for a polarization qubit. In the process we highlight some of subtleties involved in common methods for generating decoherence in quantum optics.
On understanding the figures of merit for detection and measurement of x-ray polarization  [PDF]
Martin C. Weisskopf,Ronald F. Elsner,Stephen L. O'Dell
Physics , 2010, DOI: 10.1117/12.857357
Abstract: The prospects for accomplishing X-ray polarization measurements appear to have grown in recent years after a more than 35-year hiatus. Unfortunately, this long hiatus has brought with it some confusion over the statistical uncertainties associated with polarization measurements of astronomical sources. The heart of this confusion stems from a misunderstanding (or potential misunderstanding) of a standard figure of merit-the minimum detectable polarization (MDP)-that one of us introduced many years ago. We review the relevant statistics, and quantify the differences between the MDP and the uncertainty of an actual polarization measurement. We discuss the implications for future missions.
MEASUREMENT OF GEOMETRIC FIGURES IN MS EXCEL - DEMONSTRATION / Demonstrace mě ení geometrickych útvar v excelu
Pejsar Zdeněk
Technológia vzdelávania , 2009,
Abstract: There are some standard PC programmes designed for certain mathematical disciplines that are used for demostration of mathematical objects and their qualities. Such programmes are usually expensive. The aim of this contribution is to show how to use MS Excel in a nonstandard way i.e. to demonstrate the measurement of geometric figures.K demonstraci matematickych objekt a jejich vlastností se vyu ívajú standardní po íta ové programy ur ené matematické disciplíny. Jedná se vět inou o programy ú elové a poměrně drahé. P íspěvek si klade za cíl ukázat vyu ití dostupného programu MS EXCEL k nestanfdardním ú el m, tj. k demonstraci mě ení geometrickych tvar .
Single nanoparticle measurement techniques  [PDF]
W. Wernsdorfer,D. Mailly,A. Benoit
Physics , 1999, DOI: 10.1063/1.373259
Abstract: Various single particle measuring techniques are briefly reviewed and the basic concepts of a new micro-SQUID technique are discussed. It allows measurements of the magnetization reversal of single nanometer-sized particles at low temperature. The influence of the measuring technique on the system of interest is discussed.
Quantum dynamics in single spin measurement  [PDF]
Stefano Mancini,David Vitali,Hector Moya-Cessa
Physics , 2003, DOI: 10.1103/PhysRevB.71.054406
Abstract: We study the quantum dynamics of a model for the single-spin measurement in magnetic-resonance force microscopy. We consider an oscillating driven cantilever coupled with the magnetic moment of the sample. Then, the cantilever is damped through an external bath and its readout is provided by a radiation field. Conditions for reliable measurements will be discussed.
Conditional Stability for Single Interior Measurement  [PDF]
Naofumi Honda,Joyce McLaughlin,Gen Nakamura
Mathematics , 2013, DOI: 10.1088/0266-5611/30/5/055001
Abstract: An inverse problem to identify unknown coefficients of a partial differential equation by a single interior measurement is considered. The equation considered in this paper is a strongly elliptic second order scalar equation which can have complex coefficients in a bounded domain with $C^2$ boundary and single interior measurement means that we know a given solution of the equation in this domain. The equation includes some model equations arising from acoustics, viscoelasticity and hydrology. We assume that the coefficients are piecewise analytic. Our major result is the local H\"older stability estimate for identifying the unknown coefficients. If the unknown coefficients is a complex coefficient in the principal part of the equation, we assumed a condition which we named admissibility assumption for the real part and imaginary part of the difference of the two complex coefficients. This admissibility assumption is automatically satisfied if the complex coefficients are real valued. For identifying either the real coefficient in the principal part or the coefficient of the 0-th order of the equation, the major result implies the global uniqueness for the identification.
Measurement of refractive index of single microparticles  [PDF]
Gregor Knoener,Simon Parkin,Timo A. Nieminen,Norman R. Heckenberg,Halina Rubinsztein-Dunlop
Physics , 2006, DOI: 10.1103/PhysRevLett.97.157402
Abstract: The refractive index of single microparticles is derived from precise measurement and rigorous modeling of the stiffness of a laser trap. We demonstrate the method for particles of four different materials with diameters from 1.6 to 5.2 microns and achieve an accuracy of better than 1%. The method greatly contributes as a new characterization technique because it works best under conditions (small particle size, polydispersion) where other methods, such as absorption spectroscopy, start to fail. Particles need not be transferred to a particular fluid, which prevents particle degradation or alteration common in index matching techniques. Our results also show that advanced modeling of laser traps accurately reproduces experimental reality.
Single beam interferometric angle measurement  [PDF]
Pierdomenico Paolino,Ludovic Bellon
Physics , 2006, DOI: 10.1016/j.optcom.2007.07.060
Abstract: We present an application of a quadrature phase interferometer to the measurement of the angular position of a parallel laser beam with interferometric precision. In our experimental realization we reach a resolution of 6.8e-10 rad (1.4e-4 arcsec) for 1 kHz bandwidth in a 2e-2 rad (1 deg) range. This alternative to the optical lever technique features absolute calibration, independence of the sensitivity on the thermal drifts, and wide range of measurement at full accuracy.
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