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131.
With increasing internationalization of urban planning throughout the twentieth century and in the past several decades in particular, planning ideas and practices have been exported from a few, and imported in many countries. However, this ‘trade’ happens without clear expectations about the ensuing dynamics between the internal context and external influences. This paper attempts to enhance understanding of how planning systems evolve and which factors affect them. The conceptual frameworks and typologies used to characterize planning systems and their determinants are reviewed. Building on previous work, an integrated framework is proposed that captures the process, factors and outcomes of urban planning systems. The history of planning in Serbia and Montenegro is used to illustrate how a planning system evolves under changing circumstances and influences and to demonstrate the complexity of such process. The case study is not intended to provide a detailed historical account of the country’s planning trajectory, but to highlight the applicability of elements of the framework in a real setting. In particular, the focus is on conditions of imposition versus voluntary adoption of planning ideas as a way of examining the interaction between the local context and imported models, as well as the implications of such interaction. The article concludes with several pointers about the necessary research on the nature of planning exports and imports and their effects on the resultant urban systems, processes, environments and quality of life. 相似文献
132.
Slađana Žilić Zorica Basić Vesna Hadži‐Tašković Šukalović Vuk Maksimović Marijana Janković Milomir Filipović 《International Journal of Food Science & Technology》2014,49(4):1040-1047
The content of tocopherols, B vitamins, as well as free soluble, soluble conjugated and insoluble bound phenolic compounds was determined in untreated, steeped and sprouted wheat grains. Antioxidant capacity of whole wheat grains and their phenolic fractions was also evaluated. Sprouting significantly increased the levels of tocopherols, niacin, riboflavin, as well as free and bound phenolic compounds improving nutritional value and antioxidant capacity of wheat grains/flour. After sprouting for 5 days, the content of total phenolics, flavonoids and ferulic acid calculated as the sum of its fractions was increased by 9.9, 30.7 and 21.6%, respectively. The content of α‐, β+γ‐ and δ‐tocopherols was increased for 3.59‐fold, 2.33‐fold and 2.61‐fold respectively, while the content of niacin, as predominant B vitamin, was increased for 1.19‐fold after sprouting. The total antioxidant capacity of untreated, steeped and sprouted whole wheat grains was 19.44, 20.37 and 22.70 mmol Trolox Eq/kg, respectively. Sprouted wheat, as a rich source of bioavailable phytochemicals, should be used to improve the nutritional quality of food. 相似文献
133.
Black, green and mixed paints were prepared from organically modified siloxane resin. The solar absorptance (as) of prepared black paint/metal coatings was 0.90 with corresponding thermal emittance (eT) 0.20, whereas green paint coatings did not reach satisfactory solar absorptance (as<0.8O). To improve the absorptance of the green coating, the black paint was admixed into the green paint. Optical properties of the prepared coatings were determined by the help of Kubelka–Munk formalism. 相似文献
134.
Dejan Bezbradica Dušan Mijin Mladen Mihailović Zorica Knežević‐Jugović 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(11):1642-1648
BACKGROUND: Immobilization of lipase (triacylglycerol acylhydrolase EC 3.1.1.3) from Candida rugosa on Eupergit® C and Eupergit® C 250L was performed under microwave irradiation in order to reduce immobilization time. Lipase loading, hydrolytic activity, esterification activity and operational stability in organic solvent of immobilized lipase preparation were determined. RESULTS: The microwave‐assisted procedure resulted in a 29% lower lipase loadings, compared with immobilized lipase obtained without microwaves. In hydrolytic activity assay, lipase immobilized under microwaves exhibited a 23% higher specific activity. Slight activation of lipase by microwave‐assisted immobilization was observed, since specific activity was around 5% higher than for free lipase. Lipase of highest activity was obtained after 2 min immobilization on Eupergit® C. The same preparation exhibited high esterification activity in organic medium and a half life of 212 h was determined in multiple use assay. CONCLUSION: The application of microwave irradiation leads to reduction of immobilization time from 2 days to only 2 min. The immobilized lipase obtained has prospects for further application due to its high retained activity and stability. Copyright © 2009 Society of Chemical Industry 相似文献
135.
The influence of paint dispersion parameters on the spectral selectivity of black-pigmented coatings
Marta Klanj
ek Gunde Zorica Crnjak Orel Michael G. Hutchins 《Solar Energy Materials & Solar Cells》2003,80(2):239-245
The optical properties of variously prepared black-pigmented solar absorbing paints were calculated in terms of their effective absorption and scattering abilities. The phenomenological two-parameter Kubelka–Munk effective medium theory was applied. Paints with the same composition were prepared for different degrees of pigment dispersion and characterized by the average size of pigment agglomerates present in the pigment/vehicle system. Prepared paints were applied to aluminum foil in two ways, by coil coating and by spraying. The size of coarse pigment particles and the paint application technique influence the spectral selectivity and thus determine the final performance of spectrally selective surfaces. 相似文献
136.
In dental-prosthetic practice, various kinds of fixed dentures, crowns and bridges, have very often been used in order to replace natural teeth and to respond to all health and esthetic needs. This study investigated the effect of saliva medium on migration of ions of heavy metals from fixed dentures that were fixed with various cements. Also, the influence of saliva medium on natural human teeth was observed. Potentiometric stripping analysis was used in order to determine the content of toxic heavy metals in the examined samples. The study confirmed that synthetic saliva had no significant influence on heavy metal ion migration from the natural teeth, whereas slight migration of some observed toxic heavy metal ions from the fixed dentures was present. This, however, indicates that these contents, although very low, must be taken seriously, because the above mentioned metals have cumulative effect which after some period of time may lead to functional disorders of some organs, and even to some very serious diseases. 相似文献
137.
Jelena Krstić Jelena Spasojević Aleksandra Radosavljević Aleksandra Perić‐Grujić Momčilo Đurić Zorica Kačarević‐Popović Srđan Popović 《应用聚合物科学杂志》2014,131(11)
A nanosilver (nano‐Ag)/poly(vinyl alcohol) (PVA) hydrogel device was synthesized with γ irradiation because it is a highly suitable tool for enhanced nano‐Ag technologies and biocompatible controlled release formulations. The amount of the Ag+ ions released in vitro by the nano‐Ag/PVA hydrogel device was in the antimicrobial parts per million concentration range. The modeling of the Ag+ ion release kinetics with the elements of the drug‐delivery paradigm revealed the best fit solution (R2 > 0.99) for the Kopcha and Makoid–Banakar's pharmacokinetic dissolution models. The term A/B, derived from the Kopcha model, indicated that the nano‐Ag/PVA hydrogel was mainly an Ag+‐ion diffusion‐controlled device. Makoid–Banakar's parameter and the short time approximated Ag+‐ion diffusion constant reflected the importance of the size of the Ag nanoparticles. However, it appeared that the cell oxidation potential of the Ag nanoparticles depended on the diffusion characteristics of the fluid penetrating into the Ag/PVA nanosystem. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40321. 相似文献