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Abstract  

The results obtained by studying decarbonization of different samples of Estonian limestone and dolomite and the following sulphation or carbonation of calcined products to estimate their SO2 and CO2 binding ability were presented. Experiments were carried out with thermogravimetric equipment(Q-Derivatograph, MOM and Labsys™, SETARAM) – calcination of the samples in the atmosphere of air with the heating rate 10 K per minute using multiplate crucibles, the following sulphation or carbonation of the calcined products after cooling to the fixed temperature (temperature range 400–900C) under isothermal conditions in the flow of air-SO2 or air-CO2 mixture. Chemical, X-ray, BET nitrogen dynamic desorption, etc. methods for the characterization of the initial samples, intermediate and final products were used. In addition, the possibilities of recurrent use of oil shale ashes taken from different technological points at operating thermal power plants (Estonian and Baltic TTPs, Estonia) as sorbents for SO2 binding from gaseous phase were studied, as well as the possibilities of activation of these ashes towards SO2 binding. The results of these studies confirmed the high reactivity of Estonian limestone and dolomite towards SO2 and CO2. Dependence of SO2 binding mechanism on the SO2 concentration has been established. Modelling of SO2 capture of dolomite and limestone was carried out to establish the kinetic parameters of these processes. The possibilities of activation of oil shale ashes and their effective recurrent use for binding SO2 and CO2 from gaseous phase were confirmed.

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The collaboration model of Kretschmer was applied to the co-authorshipnetwork of Indian medicine with the aim of being able to observe changes instructure over a period of 30 years. The idea of Liang, on her “Distributionof Major Scientific and Cultural Achievements in Terms of Age” was putin relation to the collaboration model by Kretschmer.

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In an attempt to decrease the emanating power of uranium and radium mill tailings, the tailings226Ra+2 were incorporated onto/into an alkaline earth sulfate crystal lattice. The difference in emanating power of aged and fresh crystals spiked with226Ra+2 solution to be adsorbed and incorporated into the sulfate crystal lattice was compared. The tailings were treated in three different slurries. The results indicate that treatment of tailings (by slurry) with BaSO4 is an effective method for reducing the emanating power of mill tailings when either deionized or HNO3 is used for a transfer medium of226Ra+2.

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This paper is the continued study on age structure of scientific collaboration in Chinese computer science. Based on an extended database a new method is used to analyze the nature and preference of collaboration. Observed values of two- three- and four-dimensional collaboration were compared respectively with their expected values. Investigation covered co-authors" combination patterns, name permutations in their papers, especially the age of the first author.

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Abstract  

The present paper describes the application of growth models as suggested by Egghe and Ravichadra Rao (Scientometrics 25:5–46, 1992). The scope of the paper is limited to study the growth and dynamics of Indian and Chinese publications in the field of liquid crystals research (1997–2006).

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Summary  

The rhythm of science may be compared to the rhythm of music. The R-indicator studied in this article is a complex indicator, trying to reflect part of this rhythm. The R-indicator interweaves publication and citation data over a long period. In this way R-sequences can be used to describe the evolutionary rhythm of science considered in a novel way. As an example the R-sequence of the journal Science from 1945 on is calculated.

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Abstract  

The growing importance of collaboration in research and the still underdeveloped state-of-the-art of research on collaboration have encouraged scientists from16 countries to establish a global interdisciplinary research network under the title “Collaboration in Science and in Technology” (COLLNET)with Berlin as its virtual centre which has been set up on January 1st, 2000.The network is to comprise the prominent scientists, who work at present mostly in the field of quantitative science studies. The intention is to work together in co-operation both on theoretical and applied aspects.

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This study aims at detecting the role of individual journals and uncovering structural patterns of information flow among scientific journals in a cross-citation network, using different bibliometric indicators and statistical methods of data analysis. Beyond measuring the individual journals’ position within the communication network, we shed light on their cognitive background as well. Language barrier and lacking internationality proved one of the main hindrances for integration into the communication network. Moreover, some document types hinder journals from establishing self-links. Against our expectations, we have found a clear divergence between strongly interlinked and high-entropy journals. Furthermore, the analysis of strong links among different fields allows the detection of high-interdisciplinary journals.

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Abstract  

Studying three Chinese major universities of different type, this article attempts to validate earlier results related to authors' name order in papers co-authored by graduate candidates and their supervisors. Candidates for the doctoral degree as well as the master's degree are considered. Defining the g-ratio as the fraction of co-authored publications where the graduate student's name precedes that of the supervisor's we obtain the following results. 1) Generally, master's level g-ratios are smaller than the corresponding doctoral level g-ratios. 2) The three doctoral g-ratio time series have a common characteristic: they tend to a limiting target value of somewhat more than 80%. The master's time series of the three universities extend themselves in parallel with the doctoral time series. 3) The g-ratio of collaborative papers related to the dissertation is higher than the g-ratio of collaborative papers not related to the dissertation. This is true on the doctoral level as well as on the master's level. 4) Different disciplines have different g-ratios, representing disciplinary customs in graduate candidate-supervisor collaboration, the highest g-ratio in the doctoral case occurring in biology (except for Tsinghua University that does not offer courses in biology). 5) There exist only small differences between the g-ratios of different kinds of universities. 6) In recent years, the same candidate-supervisor collaboration patterns exist in international publications as in domestic ones. The fact that the doctoral g-ratios of all three universities are as high as 80% reflects a universal regularity in the structure of scientific collaboration between doctoral candidates and their supervisors in China.

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Abstract  

Batch adsorption technique was applied to study the adsorption of radiocobalt on multiwalled carbon nanotubes (CNTs) with deferent sizes. The aim of this work was to examine the effect of contact time, pH, solid content, foreign ions and CNT particle sizes on the removal of Co(II) ions from aqueous solutions by CNTs. The results indicated that the adsorption of Co(II) was strongly dependent on pH and the adsorption capacity was in inverse proportion to the particle sizes of CNTs. The adsorption of Co(II) was weakly affected by ionic strength and foreign ions. Ion exchange and surface complexation were the main adsorption mechanisms. The kinetics of Co(II) adsorption on CNTs was described well by pseudo-second-order model. The Langmuir and Freundlich models were applied to interpret the adsorption data. The results are important to understand the physicochemical behavior of Co(II) with CNTs, and for the application of CNTs in the preconcentration of radiocobalt from large volumes of aqueous solutions.

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