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Polarography     
J Heyrovsky’s invention of polarography in which a dropping mercury electrode is used in the electrochemical cell revolutionised electroanalysis, study of electrode kinetics and adsorption studies on mercury electrodes. Polarography has also directly contributed to the development of new and innovative ideas in electrochemical techniques, instrumentation and applications  相似文献   
84.
This study explores working students' college experiences using the grounded theory approach. Focus groups were conducted to allow working students to elaborate on their college experiences, clarifying issues not easily addressed through surveys. Two theoretical propositions are offered to describe how working students are constantly searching for meaningful work as well as meaning in their work. It is important for institutions to consider work as an educationally purposeful activity outside classroom and to create job opportunities that benefit students academically, socially and financially.  相似文献   
85.
Two groups of adults on AFPA pre-qualification training schemes were each exposed to a different programme, explicitly aimed at improving their cognitive skills: Ateliers de Raisonnement Logique/Logical Reasoning Workshops and Logo exercises. They were compared with a control group receiving special treatment, members being informed that they were participating in an experiment. This latter group was exposed, for an essentially similar period, to training in the use of office-work software and computer-assisted education. The three groups were tested, at the beginning and end of the scheme, on a number of cognitive dimensions. The level of self-esteem of participants, their attitude to computers and the internality of their attributions were also evaluated. Results showed: 1) a modest increase in cognitive efficiency in each group at the end of training and ambiguous variations in conative variables; 2) no superiority of the Logo group over the control group; 3) superiority of the ARL group for two cognitive variables of the ten studied (combinatory analysis and perceptive field independence). The extent of the difference was invariably less that one standard-deviation of the distribution of scores. These results, and in particular the absence of transfer of acquisitions, seem insufficient to justify the conclusion of any specific efficacy of this last method.  相似文献   
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This study is part of a larger research project at the Image Permanence Institute dedicated to digital print preservation issues – the Digital Print Preservation Portal (DP3). Previous DP3 studies determined that certain digital print types are prone to cracking and/or abrasion, and that factors such as low relative humidity, pollutants, and light increase the brittleness of the ink-receiving layer of some inkjet papers. The purpose of this investigation was to explore if light also increases the propensity of inkjet prints to abrade, and to examine the potential of framing glazings to mitigate light-induced physical damage (cracking and abrasion) by attenuating some portion of the UV spectrum. Inkjet papers and prints were subjected to xenon lighting (to simulate daylight through window glass) without glazing, or in sealed framing packages with plain framing glass (soda-lime) or UV filtering glass. Before and after light exposure, brittleness, and abrasion resistance were evaluated independently using two tests: ISO 18907 (Imaging materials – Photographic films and papers – Wedge test for brittleness) and a rub test utilizing a Sutherland® Rub Tester. In this study, exposure to light increased the cracking and/or abrasion tendency of some specimens. The use of UV filtering glass reduced this light-induced propensity in all cases. Plain glass protected all samples from at least one of these two types of surface damage, but was less effective than UV glass. Light-induced brittleness and sensitivity to abrasion were mostly, though not exclusively, caused by UV radiation. It was also seen that some prints may become brittle and/or prone to abrasion in the absence of image fade. Budgeting the amount of light these objects can be exposed to, protecting them from UV radiation, and handling prints with caution especially after exhibition, is essential in order to limit physical damage.  相似文献   
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This paper considers the history of the emergence and development of cooperative cataloging in Russia and abroad and presents the first projects and programs in the field of cooperative cataloging: CONSER, NACO, BIBCO, and PCC. It elucidates the activity of the OCLC Center and Consortium of European Scientific Libraries, which are the first-rate international cooperative associations, as well as the ARBIKON Association and LIBNET centers which are Russian centers of cooperative cataloging.  相似文献   
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This paper analyzes modern information technologies as applied in the political environment and considers the content and peculiarities of using IT programs in strategic political modeling.  相似文献   
90.
The problem of the construction of the optimal model of the automated control system of a Russian higher-education institution (the ACS of an RHEI) is studied. This term appeared in the 1970s–1980s and served as the beginning of a project that covered more than 50 of the largest higher-education institutions of the country and is also relevant today. Two main approaches to construction of an automated control system of Russian higher-education institutions are specified, viz., the development of a system using its own resources and the use of the product from a third-party developer. Examples of the application of these approaches are given and the structure of the elements (modules) of the systems is described. The necessity to search for the optimal structure of the elements included in the ACS of an RHEI is specified for most educational organizations taking their dimensions into account and their specific sectoral character, as well as the total expenditures for the acquisition (development) and support of the systems. An example of the structure of the optimal model and a third (combined) approach to its construction is given.  相似文献   
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