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Copyright of Acta Stomatologica Croatica is the property of Acta Stomatologica Croatica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pred 30. leti, natančneje spomladi leta 1992, je bila, v okviru Odseka za anorgansko kemijo in tehnologijo Instituta “Jožef Stefan”, ustanovljena Šola eksperimentalne kemije. Zaradi razvoja znanosti in interdisciplinarnih pristopov, je njen glavni namen približevanje kemije mladim generacijam in prikazovanje njene širše uporabe v vsakdanjem življenju. Šola eksperimentalne kemije tako ustvarja pomemben most med raziskovanjem in izobraževanjem ter aktivno prispeva k popularizaciji predmetnega področja v šolah.

Copyright of Croatian Journal of Education / Hrvatski Časopis za Odgoj i Obrazovanje is the property of Uciteljski Fakultet u Zagrebu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The introduction of lubricity protection as part of the EN 590 diesel specification in Europe has led to the wide-spread use of lubricity additives as a cost effective means to achieve the required level of performance. At the moment there are a number of different lubricity additive chemistries available to refiners and some discussion as to the merits of the different products. During the initial introduction of lubricity additives for low sulphur diesel fuel certain chemistries were found to have negative interactions that led to field issues. These products were mainly acid based and found to interact with basic components present both in the fuel and in the lubricant. These issues led to a move to neutral lubricity additives being favoured in preference to products based on acidic chemistry. However, even some of the neutral chemistries were found to have negative harm effects. In this paper we will discuss how the development of no harm testing of refinery additives has led to the safe use of both neutral and acidic lubricity additives. The well-established DGMK test protocol allows refiners to select the most cost effective lubricity additive based upon extensive no harm testing in preference to selection being based upon generic chemistry. [ABSTRACT FROM AUTHOR]

Copyright of Methodological Horizons / Metodički Obzori is the property of Juraj Dobrila University of Pula and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

walls of submerged caves feeding Florida springs are often lined with a heavy mat of filamentous bacteria, many of which are able to oxidize reduced sulfur in groundwater migrating from the porous bedrock into the cave conduit. To determine changes in water chemistry as water passes through the mi-crobial mat, a simple device made from standard well screen and sealed with a rubber stopper and controllable vents was installed in a hole drilled in the wall of the cave passage. The sampler was sealed in place with marine epoxy. we measured anions in water from the sampler and from the water-filled conduit taken just outside the sampler. Most anions measured viz., Cl-, NO-, and PO4-, increased slightly between the matrix and conduit waters. However, traces of sulfide were measured in the water from the rock matrix, but not in the conduit. SO22-concentrations in the conduit were about twice that measured in the water from the sampler, about 22 and 11 mg SO- L-1, respectively, providing further evidence that sulfur oxidation is an important process in the bacterial mats attached to the lime-stone surfaces in these caves. An additional use of the sampling device is to measure discharge from the local bedrock into the cave conduit. [ABSTRACT FROM AUTHOR]

Copyright of CEPS Journal is the property of University of Ljubljana, Faculty of Education and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)