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Abstract  

An implementation of the Electron Gamma Shower 4 code (EGS4) has been developed to allow convenient simulation of typical gamma ray measurement systems. Coincidence gamma rays, beta spectra, and angular correlations have been added to adequately simulate a complete nuclear decay and provide corrections to experimentally determined detector efficiencies. This code has been used to strip certain low-background spectra for the purpose of extremely low-level assay. Monte Carlo calculations of this sort can be extremely successful since low background detectors are usually free of significant contributions from poorly localized radiation sources, such as cosmic muons, secondary cosmic neutrons, and radioactive construction or shielding materials. Previously, validation of this code has been obtained from a series of comparisons between measurements and blind calculations. An example of the application of this code to an exceedingly low background spectrum stripping will be presented.

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Abstract  

Various rice samples /seed, brand layer, husk/ from Vietnam were analyzed for Se, Hg, Cr, Ni, Sc, Rb, Fe, Zn and Co by neutron activation analysis. The concentration values found /seed/ were the following: Se 0.04–0.07 ppm, Hg 0.02–0.07 ppm, Cr 2.13–8.65 ppm, Ni 1.56–4.95 ppm, Sc 0.02–0.06 ppm, Rb 0.84–2.71 ppm, Fe 26.31–96.07 ppm, Zn 10.65–27.39 ppm and Co 0.02–0.15 ppm. The values were reported in ppm /dry weight/. Statistical analysis /t-test, t=0.05/ showed that the content of elements varies between sorts of rice; the content of Rb, Fe, Ni, Cr of rice husk was significantly higher than in rice seed and brand layer.

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Ninety-two samples of ceramics from Kommos in south-central Crete, covering the Middle Minoan periods MMI to MMIII have been analyzed by instrumental neutron activation using the SLOWPOKE reactor at the University of Toronto. The sherds represented three basic fabric types: a fine buff fabric, a stone tempered buff fabric, a coarse, stone tempered red fabric. Also included in the study were three sherds from nearby archaeological sites and six Kommos sherds which were archaeologically assessed as exhibiting atypical fabrics. The three fabric types were sortable into two distinct chemical groups, and two similar groups. Little temporal variation in chemical composition was found in the fine buff wares, and the atypical fabrics fitted neatly into three of the chemical groups.

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In a first step, definitions of the irreducible information structural categories are given, and in a second step, it is shown that there are no invariant phonological or otherwise grammatical correlates of these categories. In other words, the phonology, syntax or morphology are unable to define information structure. It is a common mistake that information structural categories are expressed by invariant grammatical correlates, be they syntactic, morphological or phonological. It is rather the case that grammatical cues help speaker and hearer to sort out which element carries which information structural role, and only in this sense are the grammatical correlates of information structure important. Languages display variation as to the role of grammar in enhancing categories of information structure, and this variation reflects the variation found in the “normal” syntax and phonology of languages.

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The presented Dictionary of Collocations is the first of its kind in Slovakia. It covers collocational profiles with nouns and is based on a lexical database of collocations in the Slovak language. The Slovak National Corpus of the Ľudovít Štúr Institute of Linguistics at the Slovak Academy of Sciences was used to conduct the research. The database covers collocational profiles of several hundred words of different parts of speech (nouns in the first phase of the project). The Dictionary is aimed at the registration and description of not only multiword lexemes, but also at the registration of the so-called typical collocations having a wide collocability. They are differentiated by frequency, and their number is limited in that way. An innovative approach has been applied for sorting out collocations in the Dictionary. The combinatory of flexional potentials of these elements are the basis for the creation of the so-called collocational templates which serve as the basis for the patterns of collocations.

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Abstract  

We report here a simple method to identify the ‘emerging topics’ in life sciences. First, the keywords selected from MeSH terms on PubMed by filtering the terms based on their increment rate of the appearance, and, then, were sorted into groups dealing with the same topics by ‘co-word’ analysis. These topics were defined as ‘emerging topics’. The survey of the emerging keywords with high increment rates of appearance between 1972 to 2006 showed that emerging topics changed dramatically year by year, and that the major shift of the topics occurred in the late 90s; the topics that cover technical and conceptual aspects in molecular biology to the more systematic ‘-omics’-related and nanoscience-related aspects. We further investigated trends in emerging topics within various sub-fields in the life sciences.

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The color pigments from different sorts of red wine (Cabernet Sauvignon, Merlot, and Burgundy) produced in different years, purchased from the Recas and Minis Romanian wineries, were separated using a new reversed-phase thin-layer chromatographic (RP-TLC) method. Chromatographic separation of the pigments was performed on silica gel RP-18F 254 with acetonitrile-water-formic acid 40:58:2 ( v/v ) as mobile phase. Most of the natural pigments are phenolic compounds with antioxidant activity that can be evaluated by use of a stable free radical, for example DPPH (2,2-diphenyl-1-picrylhydrazyl). The proposed RP-TLC method can be used in wine monitoring to identify the origin of wine and to detect adulteration.

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On self-explaining roads drivers automatically drive according to the expected behavior and speed. In order to create this type of roads, within a given road category the layout should be homogenous, whereas a remarkable difference should exist between road categories. Using a sample of 500 persons, the paper analyses, which road categories are identified and distinguished by road users.A picture sorting task was completed to find out how road users group 45 different road scenes, and how these groups correspond to the road categories according to current standards.In addition, an analysis of a questionnaire survey was used to determine how individual road scene images are grouped on the basis of chosen speeds, and how this grouping corresponds to road categories. For processing of speed data, cluster analysis was used.The result of both surveys show that road users can clearly distinguish only 4–5 road categories. The paper compares these results with the design guidelines of some countries.

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Egészséges, normális szív esetén a bal kamra bazális része szisztoléban az óramutató járásának megfelelően rotálódik, míg a szívcsúcs azzal ellentétes irányba mozdul el. Ezt a fajta facsaró-csavaró mozgást a szív csavarodásának (twist) nevezik. Ennek az összefoglaló jellegű közleménynek a célja a szív bal kamrai rotációjával és csavarodásával kapcsolatos fontos tudnivalók és vizsgálati lehetőségeinek bemutatása. Orv. Hetil., 2012, 153, 1547–1551.

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Abstract

The sculptural rendering of loose folds of clothing was part of the classical legacy, which was a salient characteristic of Bernini's figural sculpture. The expressive potential of non-figural drapes was an innovation which has seldom received adequate attention. At first sight the evocative dynamism of such independent draperies carved in marble may seem like a sort of Abstract Expressionism avant la lettre but Bernini employed the effect as a “Symbolic Form” in Ernst Cassirer's famous definition, a concrete object communicating an intelligible meaning.

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