Nostoc Linckia as Biosorbent of Chromium and Nickel from Electroplating Industry Wastewaters

The present study relates to the use of cyanobaeterium Nostoc linkia for removal of chromium and nickel from wastewater of galvanic industry. To determine concentrations of Cr and Ni in wastewater samples atomic absorption spectrometry was used. The samples of dried nostoc biomass after exposure to wastewater were subject to nondestructive instrumental neutron activation analysis. During 30 rain of the contact ofbiomass with wastewater 84% of chromium was removed from the wastewaters. Beside chromium after 30 rain nostoc biomass accumulates the amount of iron and zinc that exceeds their concentrations in the control biomass samples by a factor of 6 and 8, respectively. Nickel content in biomass after interaction with Cr-containing wastewater increases sixty fold and copper-sixteen fold. During the same time of biomass-Ni-containing wastewater interaction, 50% of nickel were accumulated. The method of Fourier transform infrared spectroscopy was applied to identify functional groups responsible for metal binding.     

Le Corbusier and Walter Gropius: contacts prior to the Second World War

Le Corbusier left neither memoirs nor a life history written with his own pen. Nonetheless, he did leave hundreds of boxes filled with diaries, letters, notes, drawings with comments attached, designs and sketches – a wealth of documentary evidence upon which future historians might reconstruct his biography. When Le Corbusier decided that he was destined to become a great architect and appointed to bring a new architecture into the world, with full deliberation, he therefore meticulously kept every shred of documentation of his life, as had Stendhal and Thomas Mann before him. Most of this vast body of information is stored at the Fondation Le Corbusier in Paris. The author of this article had the opportunity to examine this material in depth, as well as the sources found at the Bauhaus-Archiv in Berlin and the CIAM-Archiv in Zürich. The extensive documentation available made it possible to study Le Corbusier’s contacts with leading architects in many countries. This paper focuses on one of these contacts – the relationship between Le Corbusier and Walter Gropius.     

Use of functionalized organocobalt initiators in processes of emulsion polymerization

Summary Characteristics of novel organocobalt–tridentate Schiff base chelates bearing a heteroatomic group capable of donating an electron couple, namely amino or hydroxyl function, or the carboxylate anion, at the terminal position of an alkyl ligand, are reported in respect to their presumable application as initiators of radical polymerization. These processes were studied in water emulsions using styrene as a model monomer at various pH and temperatures. Polymerization rates proved relatively low if both the length of carbon chain of the alkyl ligand and pH range favored extra chelation in the given initiator due to coordination of the functional group. With this reservation, the complexes in question act as highly effective pH-dependent initiators of emulsion polymerization, by general analogy with the corresponding non-functionalized initiators. Characteristics of the polymer products, including latexes, are presented and discussed.     

Microbial conversion of sterol‐containing soybean oil production waste

Soybean extract residue (scum), a waste of soybean oil production, was examined as a raw material for C₁₇‐ketosteroid production. As a model process, its bioconversion to 9α‐hydroxyandrost‐4‐ene‐3,17‐dione (9‐OH‐AD) by Mycobacterium sp VKM Ac‐1817D was studied. The content of transformable sterols (sitosterol, stigmasterol and campesterol) in scum was estimated at ～14%. The bioconversion of scum to 9‐OH‐AD was characterized by a long lag‐period (300–350 h) followed by 9‐OH‐AD accumulation. The microbial or chemical elimination of fatty non‐identified components resulted in sterol‐enriched scum preparations. Effective conversion of these preparations by Mycobacterium sp was demonstrated: 9‐OH‐AD molar yield ～65% was reached at 60 h from the scum preparation containing 10 g dm^?3 transformable sterols. The process productivity was comparable with that for high quality‐sitosterol of wood origin (tall‐oil sitosterol). Copyright © 2004 Society of Chemical Industry     

Sustainable development of the Belgrade energy system

Cities are the most important energy consumers of any country in all energy vector components. Nowadays, Belgrade as a cultural, educational, scientific, administrative, political, and business center of the region with its own structure of production, transportation, services, and urban system, represents significant consumer of different energy forms. Only useful and final energy is delivered to energy consuming sectors of a city. Simulation model MAED was used in this paper to estimate energy demand in city for a long time period. On the basis of energy demand forecast for three major ‘energy consumers’ (sectors of household/service, industry, and transportation) until 2020, the sustainable development ‘scenarios’ of Belgrade energy system are developed (2005–2010, 2010–2015, 2015–2020). For each ‘scenario’, the energy systems of primary resources are determined so to satisfy the predicted differences in energy consumption for the mentioned time intervals until 2020. In this case different ‘scenarios’ are evaluated. The evaluation of ‘scenarios’ sustainability is obtained by method of multi-criteria analysis. Using energy indices for sustainable development, the following indices are taken into consideration for the assessment of scenario sustainability: economical, social, and environmental. The obtained results can be used by experts in decision-making process.     

Case Study of Steady Oxygen Concentration Gradients in a Groundwater Plume from a Highway Infiltration Basin

We measure and model the steady transport of specific conductivity and dissolved oxygen through a groundwater plume from a highway infiltration basin in southeastern Massachusetts. Specific conductivity is treated as a conservative surrogate for runoff contamination, and the data calibrate a 0.27-m vertical dispersivity α of the aquifer and the bottom streamline elevation of the plume, which falls to an 8-m depth below the water table. The dissolved oxygen degrades as a first order reactant in the plume to levels below 1 mg/L, with a decay constant λ of 0.12?day?1. The latter may be attributed in part to the historical use of an alternative de-icing agent calcium magnesium acetate on the highway, since acetate is a readily biodegradable substrate for microorganisms. The calibrated kinetics suggest that plume microbes and geochemistry degrade oxygen over two orders of magnitude faster than their ambient groundwater counterparts, which impose a linear decrease of dissolved oxygen concentration below the plume. Simulations suggest that the anoxic groundwater plume extends 1,600 m downgradient of the infiltration basin, a distance that will shorten by an order of magnitude if salt is used exclusively to de-ice the highway.     

Effect of ovenproof plastic films on the quality of spotted rose snapper (lutjanus guttatus) fillets during frozen storage

Spotted rose snapper (Lutjanus guttatus) fillets packed in two polymer films, polyamide 6,6 (PA66) and polyethylene terephthalate (PET), were stored at ?20°C for a period of 120 days. Films were tested for melting temperature (PA66 253–257°C and PET 252–255°C), oxygen transmission rate [PA66 51.8 ± 12.9cm³/(m²·24h·atm) and PET 152.7 ± 0.2cm³/(m²·24h·atm)] and water vapor transmission rate [PA66 17.8 ± 1.7g/(m²·24h) and PET 6.5 ± 0.2g/(m²·24h)]. Sensory analyses (firmness, flavour and appearance) were performed at 0, 30, 60, 90 and 120 days of storage after baking the fillets in the same storage bags. For raw fillets, their water‐holding capacity (WHC), total aerobic counts (TAC), pH, trimethylamine (TMA) and shear‐force resistance were measured at the same periods. Sensory analyses after baking showed no differences between the fillets packaged in the two films. The WHC, TAC, pH and TMA values in both products were kept within accepted limits. The fillets packed in PET showed a significant increase in firmness (shear‐force resistance) during the first 60 days of storage and then a decrease at 90 days due to dehydration through the film seals. Over the same period, the fillets packed in PA66 showed no significant changes in firmness. In this study, it was demonstrated that it is possible to develop a ready‐to‐bake fish fillet product by using ovenproof films for packaging during storage. Copyright © 2006 John Wiley & Sons, Ltd.     

Using Unbalanced Trees for Indexing Multidimensional Objects

In this paper we introduce a new multidimensional index structure called the S-tree. Such indexes are appropriate for a large variety of pictorial databases such as cartography, satellite and medical images. The S-tree discussed in this paper is similar in flavor to the standard R-tree, but accepts mild imbalance in the resulting tree in return for a significantly reduced area, overlap and perimeter in the resulting minimum bounding rectangles. In fact, the S-tree is defined in terms of a parameter which governs the degree to which this trade-off is allowed. We develop an efficient packing algorithm based on this parameter. We then analyze the S-tree analytically, giving theoretical bounds on the degree of imbalance of the tree. We also analyze the S-tree experimentally. The S-tree does well in two dimensions, and even better in three dimensions. Indeed, the S-tree can be expected to do better still as the dimensionality increases. While the S-tree is extremely effective for static databases, we outline the extension to dynamic databases as well.     

Elaboration in Processing Adolescent Health Messages: The Impact of Egocentrism and Sensation Seeking on Message Processing

The present studies explored how adolescents process information in making decisions about risk behavior. We studied two developmental aspects of adolescent egocentrism: personal fable (a sense of invulnerability) and imaginary audience (focus on others), along with individual difference variables (sensation seeking, self-esteem, and peer pressure). The studies investigated the effects of a message variable, elaboration demand, which is driven by a developmental view of adolescents' cognitive processing. Results of 3 studies indicated the deep elaboration message was partially effective in changing message perceptions and adolescents' intentions to behave in ways to reduce risks. The message type interacted with developmental indicators (age and cognitive development), gender, and topic to explain behavioral intentions, message perceptions and retention.