35 resultados para chemistry journals
em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain
Resumo:
Es presenten els resultats d’una enquesta sobre l’ús de revistes electròniques realitzada al professorat de les universitats que formen el Consorci de Biblioteques Universitàries de Catalunya (CBUC). Els resultats mostren un elevat grau de coneixement de la col·lecció de revistes electròniques entre el personal docent i investigador i una creixent preferència pel format electrònic en detriment de l’imprès. L’alt grau de coneixement i d’ús dels títols electrònics, i la preferència per aquest suport, comporten una elevada valoració de la col·lecció de revistes electròniques. Al mateix temps, la major part dels usuaris preveu un increment de l’ús dels títols electrònics durant els propers anys. Els resultats també confirmen la importància de la disciplina i de l’edat com a factors explicatius de l’ús de les revistes electròniques.
Resumo:
Cooperation between libraries is a universal language spoken in different dialects. In 1996 the libraries of the state-funded universities and the National Library of Catalonia (Spain) formed the Consortium of Academic Libraries of Catalonia (CBUC) to act as a channel for cooperation. The organization and activities of CBUC are an example of how this universal language has been adapted to the specific characteristics of the Libraries of Catalonia. Catalonia is an autonomous region of Spain with 7 million inhabitants with its own language, history and traditions and with a strong feeling of own identity that facilitates the cooperation. Thanks to this (and also to the hard work of the member libraries), since then, CBUC has created a union catalogue, an interlibrary lending program, the Digital Library of Catalonia, a cooperative store, different cooperatives repositories and other cooperation programs. One of these cooperatives repositories is RACO (Catalan Journals in Open Access, www.raco.cat) where can be consulted, in open access, the full-text articles of scientific, cultural and scholar Catalan journals. The main purpose of RACO is to increase the visibility and searches of the journals included and to spread the scientific and academic production published in Catalonia. This purpose makes specific in three aims: encourage the electronic edition of Catalan journals; be the interface that allows the whole search of all the journals and provide the instruments for its preservation. There are currently 244 journals in RACO, that includes more than 85.000 articles (80% in OA) from 50 publishing institutions. Since it got into operation it has had more than 4 millions of queries. These 244 journals offer the full-text of all the published issues. Nevertheless, some journal can have a delay between the introduction of the table of contents and the full-text for the recent issues. From 2005 we have a plan of retrospective digitization that has allowed to digitize more than 350.000 pages of back issues. The RACO repository works with the open source program OJS (Open Journal Systems, http://pkp.sfu.ca/ojs/) and uses Dublin Core Metadata and the interoperability protocol created by Open Archives Initiative (OAI) which allows to increase the visibility of the articles published in journals offering oneself together with other international repositories.
Resumo:
Es discuteixen breument algunes consideracions sobre l'aplicació de la Teoria delsConjunts difusos a la Química quàntica. Es demostra aqui que molts conceptes químics associats a la teoria són adequats per ésser connectats amb l'estructura dels Conjunts difusos. També s'explica com algunes descripcions teoriques dels observables quàntics espotencien tractant-les amb les eines associades als esmentats Conjunts difusos. La funciódensitat es pren com a exemple de l'ús de distribucions de possibilitat al mateix temps queles distribucions de probabilitat quàntiques
Resumo:
The use of perturbation and power transformation operations permits the investigation of linear processes in the simplex as in a vectorial space. When the investigated geochemical processes can be constrained by the use of well-known starting point, the eigenvectors of the covariance matrix of a non-centred principalcomponent analysis allow to model compositional changes compared with a reference point.The results obtained for the chemistry of water collected in River Arno (central-northern Italy) have open new perspectives for considering relative changes of the analysed variables and to hypothesise the relative effect of different acting physical-chemical processes, thus posing the basis for a quantitative modelling
Resumo:
This paper presents the results of a survey of academics affiliated to the universities that are members of the Consortium of Academic Libraries of Catalonia (CBUC), and an analysis of the availability in the libraries of these universities, of the references cited in a sample of articles published by these academics. The results reflect the major importance that researchers assign to scholarly journals as the main source of scientific information. Most state that they use electronic journals either exclusively or in any case more than print journals, a preference that is higher among younger scholars. With regard to frequency of reading, four out of ten researchers state that they read journals virtually every day, while nine out of ten report that they do so at least once a week. Scholars claim that the obstacles they face when trying to download an article are related to the lack of subscriptions. However, the availability study showed that most of the articles cited in their publications are available at least at one of the CBUC libraries. Though most researchers keep a copy of the articles they consult, just over a third of them use some kind of reference management software.
Resumo:
The identification of compositional changes in fumarolic gases of active and quiescent volcanoes is one of the mostimportant targets in monitoring programs. From a general point of view, many systematic (often cyclic) and randomprocesses control the chemistry of gas discharges, making difficult to produce a convincing mathematical-statisticalmodelling.Changes in the chemical composition of volcanic gases sampled at Vulcano Island (Aeolian Arc, Sicily, Italy) fromeight different fumaroles located in the northern sector of the summit crater (La Fossa) have been analysed byconsidering their dependence from time in the period 2000-2007. Each intermediate chemical composition has beenconsidered as potentially derived from the contribution of the two temporal extremes represented by the 2000 and 2007samples, respectively, by using inverse modelling methodologies for compositional data. Data pertaining to fumarolesF5 and F27, located on the rim and in the inner part of La Fossa crater, respectively, have been used to achieve theproposed aim. The statistical approach has allowed us to highlight the presence of random and not random fluctuations,features useful to understand how the volcanic system works, opening new perspectives in sampling strategies and inthe evaluation of the natural risk related to a quiescent volcano
Resumo:
A comparative systematic study of the CrO2F2 compound has been performed using different conventional ab initio methodologies and density functional procedures. Two points have been analyzed: first, the accuracy of results yielded by each method under study, and second, the computational cost required to reach such results. Weighing up both aspects, density functional theory has been found to be more appropriate than the Hartree-Fock (HF) and the analyzed post-HF methods. Hence, the structural characterization and spectroscopic elucidation of the full CrO2X2 series (X=F,Cl,Br,I) has been done at this level of theory. Emphasis has been given to the unknown CrO2I2 species, and specially to the UV/visible spectra of all four compounds. Furthermore, a topological analysis in terms of charge density distributions has revealed why the valence shell electron pair repulsion model fails in predicting the molecular shape of such CrO2X2 complexes
Resumo:
Site licensing of e-journals has been revolutionizing the way academicinformation is distributed. However, many librarians are concerned aboutthe possibility that publishers might abuse site licensing by practicingbundling. In this paper, we analyze the private and social incentives forthe publishers to use bundling in the context of STM electronic journalmarket. In the short run in which the number of journals is exogenouslygiven, we find a strong conflict between the two incentives: each publisherfinds bundling optimal and bundling increases the industry profit butreduces social welfare. However, in the long run we find that publishersmight have higher incentives to introduce new journals under bundlingthan without bundling and, in this case, bundling can reduce the industryprofit while increasing social welfare. Finally, we examine publishers incentive to provide links to the websites of the rival publishers underbundling and show that even asymmetric publishers have incentive tointerconnect.
Resumo:
More and more academic journals adopt an open-access policy, by which articlesare accessible free of charge, while publication costs are recovered through authorfees. We study the consequences of this open access policy on a journal s qualitystandard. If the journal s objective was to maximize social welfare, open accesswould be optimal as long as the positive externalities generated by its diffusionexceed the marginal cost of distribution. However, we show that if an open accessjournal has a different objective (such as maximizing readers payoffs, the impactof the journal or its profit), it tends to choose a quality standard below the sociallyefficient level.
Resumo:
The recent surge in scientific electronic journals began when libraries began having access to the WWW in the mid-1990s. The shift from paper to digital has affected the traditional alignment and role of the primary "stakeholders" -mainly authors, publishers, universities and libraries. The author offers a brief review of the history of the scholarly journal followed by the evolution of e-journals in during the past two decades. The article then focuses on the implications that these have had on traditional library processes and services such as selection, acquisitions, cataloguing, storage, preservation and user services. In the conclusion the author speculates on the long term effect of Web-based publishing on the format of the traditional scholarly journal as it has existed for over 300 years.
Resumo:
A qualitative study of the impact of electronic journals on the information behavior of academics at Catalan universities shows that academics now read more, and more widely. However, their reading is becoming more superficial; they are compelled to improve their discrimination skills in order to decide what to read in more depth. The electronic accessibility of journals means that academics now make fewer library visits. Web browsing and TOC e-mail alerts are replacing physical browsing, and searching is a very popular option for keeping up to date with developments. Internet search engines, especially Google and Google Scholar, are becoming important sources of information for academics. However, they face problems in managing their personal scientific information.
Resumo:
This paper examines the most productive authors, institutions and countries in regional and urban science from 1991 to 2000 using information on published articles (and pages) from a sample of widely recognized journals in this field: ARS, JUE, JRS, IJURR, IRSR, PRS, RSUE, RS and US. We also consider the relation between the country of the institution named in articles and the country in which the journal is published, in order to know if there are a home publication bias in regional and urban science. Analysis was made for the whole decade and by subperiods, this allowed us to make a more dynamic interpretation of the results
Resumo:
This paper examines the most productive authors, institutions and countries in regional and urban science from 1991 to 2000 using information on published articles (and pages) from a sample of widely recognized journals in this field: ARS, JUE, JRS, IJURR, IRSR, PRS, RSUE, RS and US. We also consider the relation between the country of the institution named in articles and the country in which the journal is published, in order to know if there are a home publication bias in regional and urban science. Analysis was made for the whole decade and by subperiods, this allowed us to make a more dynamic interpretation of the results
Resumo:
Content and Language Integrated Learning (CLIL)Materials in Chemistry and English following the principles of CLIL / Content-based Instruction and Task-based Learning
Resumo:
The seven-year period studied here differs very little from the sixyear period described in the previous Report (1990-1995). Sustained growth was observed in almost all the indicators used to evaluate the resources invested and the scientific results obtained