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Copyright of Neuroradiology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Copyright of Neuroradiology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

The article presents a collection of abstracts of the research papers presented at the 57th annual meeting of the Association of American Geographers, which was held in Miami Beach, Florida in April, 1962. The papers listed here includes "The Campus Fringe--A Landscape Phenomenon," by John Alexander. This paper analyses the problems related to the expansion of universities including that of campus fringe, the area which surround a college or university. What are the problems of campus fringes, How have these problems been faced by different schools, are there any principles which research geographers might discover which would be useful to campus authorities facing decisions regarding expansion problems, all these points have been considered by the researcher. more...

BSTRACT A comparative evaluation is made of the frequency of air mass and frontal types during a 4-year representative portion of the drought as opposed to an equivalent non-drought period. Selection of the non-drought period is based on the Palmer Drought Index. Results indicate a statistically significant increase in the occurrence of continental polar air during the drought. Other conclusions concerning conditions during the drought, not statistically significant but worth further study, are: lower frequency of maritime tropical air in the summer months, more occurrences of cold and occluded fronts, and fewer occurrences of stationary fronts. [ABSTRACT FROM AUTHOR] more...

For to år siden kunne Det Norske Meteorologiske Institutt feire 75-års jubileum og i år er det 25 år siden den moderne norske værvarsling tok sin begynnelse. Det kan derfor vtere av interesse å se på noen karakteristiske utsnitt av metorologiens historie i Norge. [ABSTRACT FROM PUBLISHER] more...

The factors controlling the ice nucleation efficiency are studied in this paper on suitably chosen model substances, in particular on silicon. It is found that the critical supersaturation for the growth of ice on a (111)-plane of GaAs is 25% at −25°C; this quantity as well as the number of growing ice crystals (cm) were found to be independent of the dislocation density. The critical supersaturation for the growth of ice on the (111)-plane of Si is strongly dependent on the electrical conductivity of the crystals, but independent of the sign of the majority charge carriers. Epitaxial growth is observed on the hexagonal substrate GaSe only, but not on the cubic GaAs and Si. On the basis of the classical nucleation theory the free energy of adsorption of HO on GaSe Δ G=0,48 eV and the specific interfacial free energy σ=23,2 erg · cm are evaluated. This indicates that the outermost layer of the ice embryo is in a liquid-like state. Water adsorption isotherms were measured gravimetrically down to −20°C and were found to be of type II (BET, [33]). The amount of adsorbed water and the isosteric heat of adsorption at a given relative pressure depend on the doping of the sample. From this it is concluded that low conductivity material had more adsorption sites than high conductivity material, but these fewer sites on the high conductivity samples were more active in collecting water molecules. The larger water clusters are formed on high conductivity samples in agreement with the higher nucleation efficiency observed in mixing cloud chamber experiments. The electrical conductivity and the sign of the thermoelectric effect of a thin silicon on sapphire film have been measured as a function of oxygen and water vapor pressures. It is found that band bending towards an n-type surface occurred during water chemisorption on Si. This indicates that chemisorbed water molecules act as donor surface states. The charge exchanged between adsorbate and adsorbent is larger on high conductivity samples on account of their higher initial surface potential. Chemisorption sites on Si are proportional to the doping concentration and they produce relatively large water clusters. Hence doping results in a higher nucleation efficiency. [ABSTRACT FROM AUTHOR] more...

In the present work a turbulence model is set up which shows accrescence qualities for small droplets during its time of diffusion dissociation. At the same time the life time of the single element, and by that the quantitative accrescence ratio which originates in an turbulence element, is defined by the genral turbulence statistic. By means of a calculated example it is shown how the accrescence density in one real situation is being computed for a whole statistical ensemble. The results show good conformity with available experimental data. [ABSTRACT FROM AUTHOR] more...

Copyright of Studia Geophysica & Geodaetica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...