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Tudománymetria: Mit Mérünk, Mit Hasonlíthatunk Össze És Mivel? •

A régészek képe a tudományos referencia adatbázis tükrében

Archaeologiai Értesítő
Author: F. Romhányi Beatrix

Tudomány ( Budapest ) 180 , 1158 – 1165 . Sasvári Péter László – Nemeslaki András 2017 Tudományos folyóiratok méltányos rangsorolása az MTA gazdasági és jogi osztályában: mit mutatnak az adatok? Magyar Tudomány ( Budapest ) 178 , 71 – 79

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derivatives in the chosen models ensure the system's stability. The proposed control law is characterized by several adjustable parameters. The adaptation mechanism used to adjust the parameters is a combination between the MIT and Lyapunov stability methods

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Thelen , E. , Smith , L. B. ( 1993 ) A dynamic systems approach to the development of cognition and action . The MIT Press , Cambridge Tinbergen

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The influence of remelting temperatureT f on allotropic transformation of amorphous sulfur with admixtures 2, 4 and 6 at.% Se has been investigated.

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. To this aim, a select group of eight economics departments in the US and EU are considered: (1) Department of Economics, Harvard University; (2) Department of Economics, Massachusetts Institute of Technology (MIT); (3) Department of Economics

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Abstract  

Hexachlororuthenat (III) and the ruthenylion (RuO2+) react with dithizone on heating in weak acid water—ethanol solution. The complexes formed can be extracted into chloroform. Based on this reaction, a reproducible, selective determination of ruthenium (20 ppb) is achieved by means of substoichiometric isotope dilution analysis, using106Ru.

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Abstract  

The binary systems of urea with polyethylene glycols 6000 and 4000 show inclusion compounds with higher melting points than the two components (m.p. 143 and 142.5°C resp.). From the melt unstable forms crystallize beside the stable crystal modifications. These have also been identified by FTIR microscopy and X-ray powder diffractometry. The phase diagrams are uncommon in so far as the inclusion compounds do not form eutectics but monotectics with both components. The inclusion compounds of the two polyethylene glycols with urea are isomorphous and form a series of mixed crystals following the Roozeboom I type of diagram.

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When the Derivatograph Q 1500 D is used for thermal measurements at high sensitivity, some disturbances must be taken into account. The influence of the following processes on the results is discussed: (1) variations in buoyancy, (2) frictional forces on the sample holder caused by streaming gas and (3) loss of adsorbed layers from the inert substance during simultaneous TG-DTA measurements.

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Abstract  

In 6 female patients with classical rheumatoid arthritis D-Penicillamine was administered in a daily dose of 250–500 mg for 3 weeks. The only additional antiphlogistic treatment was indomethacine (100–150 mg daily). At the excretion with urine were determined using n-activatinganalysis and atomabsorption. The following results were obtained an increase of zinc excretion in urine during the whole trial; a decrease of blood levels of zinc until the 2nd week of treatment followed by an increase in the 3rd week above the level of the controls before D-Penicillamine therapy started.

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Abstract  

A suitable standard smaple was developed and tested on the basis of phosphorus for the quantitative autoradiography of elements of interest in semiconductor technology. By the aid of silicon disks with a phosphorus concentration of 6·1017 atoms·cm−2 the error of the quantitative autoradiographic method is determined. The relative mean error of the density measurement is at best ±4%; the relative mean error of the determination of phosphorus concentration by use of an error-free standard sample is about ±15%. This method will be extended to other elements by use of this standard sample of phosphorus.

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