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Abstract  

We consider some of the conditions associated with ergodicity-breaking and vitrification, in particular the equivalent, in quench vitrification, of the ωτ=1 condition that is well-known in relaxation spectroscopy. For a given quench rate, Q=dT/dt, strong liquids are trapped at much higher temperatures, relative to T g, than are fragile liquids. We relate the trapping of the system during quenches to the multidimensional 'energy landscape' by means of which the configurational microstates of the system are defined. To characterize the energy landscape at energy levels that are usually associated with fluid materials, we use differential scanning calorimetry on hyperquenched glasses. This yields not only the excess potential energies of the states trapped-in during quench Q, but also the trap depths. The latter are found to be much smaller, relative to kT g, for strong liquids than they are for fragile liquids.

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Abstract  

Radioactivity has been known for more than a hundred years. Nuclear data compilations through nuclide charts began in the 1920s with the work of Soddy, and were later rationalized in the Karlsruher Nuklidkarte. For 50 years, it has depicted the status of our nuclear knowledge in an easy reading form. It was born as an educational and scientific tool that gives access to the basic bricks that the nuclear Physics community needs to build the physics knowledge at the femtometer (10−15 m) level. Nuclide data is a bridge between research and development. On the one hand, the nucleus can be regarded as a vast laboratory with, the possibility to test from fundamental concepts of the Standard Model to the genesis of the elements in the Universe. On the other hand, this data is also leading to applications in many areas of everyday life such as health care or environmental monitoring.

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Abstract  

In this paper we introduce two key notions related to understanding the glassy state problem. One is the notion of the excitation profile for an amorphous system, and the other is the notion of the simple glassformer. The attributes of the latter may be used, in quite different ways, to calculate and characterize the former. The excitation profile itself directly reflects the combined phonon/configuron density of states, which in turn determines the liquid fragility. In effect, we are examining the equivalent, for liquids, of the low temperature Einstein-Debye regime for solids though, in the liquid heat capacity case, there is no equivalent of the Dulong/Pettit classical limit for solids.To quantify these notions we apply simple calorimetric methods in a novel manner. First we use DTA techniques to define some glass-forming systems that are molecularly simpler than any described before, including cases which are 80 mol% CS2, or 100% S2Cl2. We then use the same data to obtain the fragility of these simple systems by a new approach, the 'reduced glass transition width' method. This method will be justified using data on a wider variety of well characterized glassformers, for which the unambiguous F 1/2 fragility measures are available. We also describe a new DTA method for obtaining F 1/2 fragilities in a single scan. We draw surprising conclusions about the fragility of the simplest molecular glassformers, the mixed LJ glasses, which have been much studied by molecular dynamics computer simulation.These ideas are then applied to a different kind of simple glass — one whose thermodynamics is dominated by breaking and making of covalent bonds — for which case the excitation profile can be straight-forwardly modeled. Comparisons with the profile obtained from computer studies of the molecularly simple glasses are made, and the differences in profiles implied for strong vs. fragile systems are discussed. The origin of fragility in the relation between the vibrational and configurational densities of states is discussed, and the conditions under which high fragility can convert to a first order liquid-liquid transition, is outlined.

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al., 2013. Detection of long-term landscape changes and trajectories in a Pannonian sand region: comparing land-cover and habitat-based approaches at two spatial scales. Community Ecology. 14 . (2) 219

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Journal of Radioanalytical and Nuclear Chemistry
Authors: F. Pavlotskaya, I. Kazinskaya, E. Korobova, B. Myasoedov, and V. Emelyanov

Abstract  

Various geochemically linked landscapes were studied for the distribution of Chernobyl plutonium in soils.

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Abstract  

Results of landscape and experimental investigations were used to subdivide the Belarus territory into four regions which differ both in natural features and characteristics of contamination from the Chernobyl accident.

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Summary  

Thermal analysis of the 10 m surface of materials using TA Instruments' -TA thermal probe and pulsed force mode AFM has shown promising results. This addresses the need of additional surface characterization based on principle of Thermal Analysis, which is complementary to other surface characterization techniques, i.e., Surface-IR, TOF-SIMS, etc. The method calls for identification of surface landscape by imaging first, followed by fast heating the spots of interest. The micro thermal probe is viewed to heat a small material with a tiny heater rather than to heat small material with a large heater in conventional thermal analysis. In this paper, we demonstrate the applicability in the adhesion temperature of the topical coatings of Tyvek HDPE sheets, fusion of the heat-processed polyethylene fibers in a bundle, the surface crystallinity of PET pellets, and two examples of phase images of toughened Nylon 66. Comparisons were made where it is possible with standard thermal analysis techniques as well as with the microscopic techniques of AFM, TEM and optical.

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on the Bronze Age tell in Százhalombatta and in its surroundings . In: Changes in landscapes in the Carpathian Basin. Changes in the man-made environment . (Ed: F üleky , G y . ) 9 – 12 . Környezetkímélő Agrokémiáért Alapítvány . Gödöllő

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., 2010. The application of GIS based decision-tree models for generating the spatial distribution of hydromorphic organic landscapes in relation to digital terrain data. Hydrol. Earth Syst. Sci. 14 . 847–857. Bou

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Electronics in Agriculture. 83 . 117 – 117 . Meyer , B. G. , Grabaum , R. , 2008 . MULBO: Model framework for multicriteria landscape assessment and

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