Quality of corn germ oil obtained by aqueous enzymatic extraction

Aqueous enzymatic extraction of corn germ oil was investigated. By applying hydrothermal pretreatment of corn germ, it was possible to inactivate native enzymes present in the germ and to loosen its structure. The corn was then ground and treated with enzymes. After the oil had been released by the enzyme reaction, it was separated by centrifugation. The quality of oil obtained by enzymatic extraction (Pectinex Ultra SP-L at 37°C, pH 5.2, for 6 h) was good. The oil had 1.5% free fatty acids; a total content of oxidation product value of 8.1; light yellow color (AOCS photometric color, 12.7; dominant wavelength λ_D=575 nm); 0.022% phosphatides; 1350 mg/kg total tocopherol; and an oxidative stability value (Rancimat test, 100°C) of 14.6 h.     

The 1923 Belgrade Master Plan – historic town modernization

The paper analyses the 1923 Belgrade Master Plan's preparation and implementation process, a significant moment in Belgrade's political and urban history when, after the First World War, the city lost its centuries-long border position, becoming the capital of a newly established extended country, the Kingdom SHS, later the Kingdom of Yugoslavia. The goal of government and city authorities was to create a representative national capital and overcome the city's existential and functional problems. Crucial to the process was the Association of Serbian Architects and Engineers’ organization of an international competition in 1921–1922. Twenty-two projects were submitted, from Vienna, Paris, Budapest, Berlin, Zurich, Prague, etc. First prize was not awarded, but 18 were rewarded and purchased. These represented the basis for creating a final plan, supervised by G. P. Kovalevsky. The 1923 Master Plan introduced very innovative and modern approaches to solving the city's problems and improving residential areas, traffic, and greenery. The paper discusses the plan's realization, its extensive changes and partial implementation, which greatly influenced later city development. Despite obstacles, the plan initiated some important and progressive ideas whose impact was vital for the functional transformation of the city and its realization represents Belgrade's modern urban heritage.     

Development and in vitro characterization of chitosan-based microspheres for nasal delivery of promethazine

Conventional and composed promethazine-loaded microspheres were prepared by spray drying of chitosan solution systems and double water-in-oil-in-water (W/O/W) emulsion systems, respectively. Double emulsions were prepared in two different feed concentrations, with chitosan dissolved in both water phases, and ethylcellulose dissolved in oil phase. Swelling and bioadhesive properties of the microspheres depended on the chitosan content, type and the feed concentration of spray-dried system. Results obtained suggested that better ethylcellulose microcapsules with promethazine in the chitosan matrix were formed when less concentrated emulsion systems were spray-dried. Thus, in case of such a system, with ethylcellulose/chitosan weight ratio of 1:2, prolonged promethazine release was obtained.     

Mapping urban assemblages: the production of spatial knowledge

This paper engages with the ontology and epistemology of urban mapping. While geographical information system (GIS) and other digital technologies have long transformed the capacities for representation of urban data, this paper explores the capacity of mapping to produce new ways of seeing, understanding, planning and designing the city. With a primary focus on urban morphology, distinctions and overlaps between mapping, diagramming, planning and designing are articulated within a framework of assemblage thinking. Through cases drawn from urban design research, we analyse the mapping of political conflict, transport flows, functional mix and informal settlement. It is argued that urban mapping is a form of spatial knowledge production that is often diagrammatic, embodying a spatial logic that cannot be reduced to words and numbers. Urban mapping constructs interconnections between the ways the city is perceived, conceived and lived; and it can reveal capacities for urban transformation – the city as a space of possibility.     

Kinetics of internal oxidation in Ag-6Sn-2In-1Te-0.2Ni and Ag-6Sn-0.6Cu-1Bi-0.2Ni type alloys

Internal oxidation process was followed in Ag-6Sn-2In-1Te-0.2Ni and Ag-6Sn-0.6Cu-1Bi-0.2Ni alloy types in free air and oxygen at 650 °C and 680 °C. It was found that the Cu and Bi bearing alloy had a higher rates of internal oxidation in all of the tested conditions, whish was due to Bi effect accelerating the internal oxidation. In the early stage of internal oxidation of the Ag-6Sn-2In-1Te-0.2Ni alloy, an inhomogeneous structure revealed, which changed to a homogenous pattern after longer oxidation times. Such a structure was suppressed in the Bi bearing alloy. The applied 6 bar oxygen atmosphere brought on a 5–6 times higher rate of internal oxidation, with a homogenous structure compared to the free air oxidation. In free air after long time oxidation (200 h–250 h), the rate of internal oxidation was found to have almost doubled in both alloys.     

Insights into the role of protein molecule size and structure on interfacial properties using designed sequences

Mixtures of a large, structured protein with a smaller, unstructured component are inherently complex and hard to characterize at interfaces, leading to difficulties in understanding their interfacial behaviours and, therefore, formulation optimization. Here, we investigated interfacial properties of such a mixed system. Simplicity was achieved using designed sequences in which chemical differences had been eliminated to isolate the effect of molecular size and structure, namely a short unstructured peptide (DAMP1) and its longer structured protein concatamer (DAMP4). Interfacial tension measurements suggested that the size and bulk structuring of the larger molecule led to much slower adsorption kinetics. Neutron reflectometry at equilibrium revealed that both molecules adsorbed as a monolayer to the air–water interface (indicating unfolding of DAMP4 to give a chain of four connected DAMP1 molecules), with a concentration ratio equal to that in the bulk. This suggests the overall free energy of adsorption is equal despite differences in size and bulk structure. At small interfacial extensional strains, only molecule packing influenced the stress response. At larger strains, the effect of size became apparent, with DAMP4 registering a higher stress response and interfacial elasticity. When both components were present at the interface, most stress-dissipating movement was achieved by DAMP1. This work thus provides insights into the role of proteins'' molecular size and structure on their interfacial properties, and the designed sequences introduced here can serve as effective tools for interfacial studies of proteins and polymers.     

TiO2 doped with nitrogen: synthesis and characterization

In this study, nitrogen-doped titanium dioxide (TiO2) powders were synthesized in two ways: by heating of titanium hydroxide with urea and by direct hydrolysis of titanium tetraisopropoxide (TTIP) with ammonium hydroxide. The samples were characterized by structural (XRD), analytical (XPS), optical (UV/Vis absorption/reflection and Raman spectroscopy) and morphological (SEM, TEM) techniques. The characterization suggested that the doped materials have anatase crystalline form without any detectable peaks that correspond to dopants. The absorption threshold of titanium dioxide was moved in the visible range of optical spectrum from 3.2 eV to 2.20 eV. Particle sizes of synthesized powders were obtained from XRD measurements and from TEM data ranging from 6-20 nm. XPS and Raman spectroscopy were used for detection of nitrogen in doped samples.