Efekat suše na vodni režim i rastenje kvinoje (Chenopodium quinoa willd.)

Quinoa (Chenopodium quinoa Willd.) is a highly nutritious Andean seed crop which shows great potential to grow under a range of different stress environments. The objective of this study was to investigate the effect of drought on water regime and the growth of quinoa variety KVL52 in controlled conditions. The results of the present experiment indicate that the reaction of quinoa plants to drought are based on drought avoidance mechanisms: reduced transpiration and sustained water uptake. Transpiration was reduced due to the decrease of stomatal conductance and leaf area development. These results could be of practical importance for testing the possibility of growing quinoa as a new drought resistant crop in Serbia.Kvinoja (Chenopodium quinoa Willd.) je nutritivno visoko vredna kultura poreklom sa Anda, koja se može gajiti u različitim stresnim uslovima spoljašnje sredine. Cilj ovih istraživanja je bio da se ispita efekat suše na vodni režim i rastenje sorte kvinoje KVL52 u kontrolisanim uslovima gajenja. Dobijeni rezultati ukazuju da su reakcije kvinoje na sušu bazirane na mehanizmu izbegavanja suše: redukciji transpiracije i održanju usvajanja vode. Transpiracija je redukovana zahvaljujući opadanju provodljivosti stoma i redukciji lisne površine. Ovi rezultati mogu biti od praktičnog značaja za testiranje mogućnosti gajenja kvinoje kao kulture koja je otporna na sušu i nova za gajenje u Srbiji

FLEXIBLE PLANNING STRATEGIES OF SUSTAINABLE CITY DEVELOPMENT

Abstract. Recognizing the uncertainty of future city development is the basic starting point of sustainable urban planning. Flexibility in design enables the development of “age-friendly cities”, reducing the risks of functional failures caused by changing living circumstances. Planning strategies that enable adaptation of the system to changing environmental, functional, social and technological conditions are essential to the long service life and the resilience of buildings and hence to sustainable city development. This paper considers the implementation of flexible design strategies within the concept of sustainability, defined as a key tool of urban renewal and resilient city development. Value-enhancing flexibility in urban and architectural design is an essential resource for all participants of integrative city development: designers, managers, financial analysts, investors, regulators and academics. Considering this, it is essential to support the flexibility in both conceptual and legislative framework of sustainable urban strategies. Key words: sustainability, flexibility, adaptability, urban resilienc

Current strategies of urban and architectural conversion as a result of increased housing demands

U postojećem svijetu društvenih i demografskih promjena koje neprestano mijenjaju i povećavaju potražnju za smještajem, iskorištavanje postojećeg građevinskog fonda za razvoj novih stambenih prostora mogao bi postati održivo rješenje problema prenapućenosti gradova. Konverzija zastarjelih zgrada, koje su izgubile svoju primarnu funkciju, u stambene objekte, jedna je od postojećih metoda za revitalizaciju visoko-urbaniziranih područja. Budući da je konverzija samo jedna od mogućih metoda urbane obnove, jer se vrlo često primijenjuju radikalnije mjere demoliranja zgrada i konverzije zemljišta, potrebno je analizirati i kvalitetu i prikladnost ovoga pristupa. U radu se naglašavaju prednosti implementiranja konverzije zgrada kad se radi o smještaju te se istražuju opće karakteristike postojećih lokalnih i internacionalnih strategija konverzije i urbane regeneracije.In the contemporary world of social and demographic changes that continuously transform and intensify the housing demands, the exploitation of existing building fund for the development of new residential environment could be a sustainable solution to the problem of overcrowding in the cities. Conversion of obsolete buildings that are out of their primary functions to residential facilities is one of the current methods of highly-urbanized areas revitalization. Since the conversion is only one of the possible methods of urban renewal, because more radical measures of building demolition and land conversion are very often applied, it is necessary to analyse the quality and suitability of this approach. The paper points out the advantages of building conversion implementation in the field of housing and explores the general characteristics of the current local and international strategies of conversion and urban regeneration

Irradiation resistance of elastomers based on ternary rubber blends reinforced by nano filler

V International Conference on Radiation in Various Fields of Research : RAD 2017 : book of abstracts; June 12-16, 2017; Budva, Montenegr

Elastomers based on NR/BR/SBR ternary rubber blend: Morphological, mechanical and thermal properties

The elastomeric materials based on NR/BR/SBR ternary rubber blend were investigated. The polyisoprene (NR), butadiene (BR) and styrene butadiene (SBR) rubbers were used as network precursors and carbon black (CB) as an active filler (60 phr) for elastomeric materials preparation. For sample preparation, the mass ratio of NR to BR was constant, 1:1, but the SBR content was varied from 0 to 80 phr. The morphological, mechanical and thermal properties of prepared elastomeric materials were determined using scanning electron microscopy (SEM), mechanical tensile measurements and thermogravimetric analysis (TGA). Mechanical properties were assessed before and after thermooxidative aging during 168 h at 100 °C. The values of tensile strength, elongation at break, and hardness decrease up to 40 phr of SBR content and after that are increasing, but abrasion resistance of ternary rubber blends increases. The thermal decomposition temperature obviously shifted to a higher temperature for the sample with 40 phr of SBR. © 2019, CI and CEQ. All rights reserved

The effect of UV irradiation on hydrolytic stability of urea-formaldehyde resins filled with thermally modified montmorillonite

The hydrolytic stability of organic-inorganic nano-composites prepared by a two-stage polymerization of urea-formaldehyde resin (UF) filled with thermally activated montmorillonite (MMT) has been assessed before and after UV irradiation. The physical modification of MMT powder (type K10 with surface area 220 – 270 m2/g) was carried out by thermal treatment. The activated samples were designated as TA-K10 and the inactivated as NA-K10. The two types of ureaformaldehyde–MMT composites (UF/TA-K10 and UF/Na-K10) were synthesized. Obtained materials have been irradiated with different wavelengths of UV light (254 and 366 nm) and after that the hydrolytic stability was evaluated on the basis of free and liberated formaldehyde after acid hydrolysis. The free formaldehyde content in sample UF/TA-K10 that was irradiated was 0.60 % and it was smaller compared to the free formaldehyde content before irradiation (0.90 %). The content of the liberated formaldehyde from the modified UF composite which contains unmodified K10 was 2.04% compared to the cross-linked UF/TA-K10 where the content of the released formaldehyde was 2.82%. After UV irradiation of the UF/TA-K10 the content of the liberated formaldehyde decreased to 0.30% (for wavelength 254 nm) and 0.90 % (for wavelength 366 nm).VII International Conference on Radiation in Various Fields of Research : RAD 2019 : book of abstracts; June 10-14, 2019; Herceg Novi, Montenegr

Informacioni potencijal kartografske vizuelizacije turističkih vrednosti

Savremena informaciona tehnologija omogućava kreativne načine kartografskog prikaza komponenata geoprostora. U procesu planiranja i korišćenje prostora kao osnovnog turističkog resursa, a u sklopu održivog razvоја, neophodno je integrisanje turizma i politike upravljanja lokalnim razvojem. Time se postiže vizija željenog pravca razvoja turizma u sklopu ukupnog ekonomskog, društvenog, kulturnog i ekološkog razvoja lokalne zajednice. Kartografskа vizuelizacijа realnog i virtuelnog geografskog prostora ima podsticajni efekat nа razvoj turizmа. Interesovanja globalnog, otvorenog društva bez granica i veliki protok turista zahteva namenske kartografske proizvode. Karta kao izvor racionalisanih informacija o fenomenima stvarnog sveta predstavlja podršku razvoju turizma. Izrada interaktivnih karata sa pratećim multimedijalnim efekatima, uticaj Interneta i korišćenja aplikacija mobilnih telefona u turističke svrhe, omogućava da se integrišu heterogeni izvori informacija u jedinstven proizvod. Interaktivnost i multimedija omogućava: proširivanje tema i sadržaja turističkih karata, atraktivni prikaz i potrebnu detaljnost turističkog sadržaja. Diverzifikacija kartografskog prikaza, primenom multimedije, omogućava se kroz kreiranje 3D modela, animacije i modela virtuelne i proširene stvarnosti. Time se proširuje značaj turistučkih karata i na delatnost procene i prognoze turističkog razvoja, različite prostorne pokrivenosti - od globalnog preko regionalnog do lokalnog nivoa. Statička 2D karta prelaskom u trodimenzionalnu vizuelizaciju geopodataka i geovirtuelno okruženje, sa orijentacijom i navigacijom proširuje razumevanje geoprostora. Pored izrade karata za turiste, neophodne su i karte koje su namenjene planiranju i regulisanju razvoja turističkih aktivnosti. Time se obezbeđuju prikazi potencijala i perspektiva turističkog razvoja kartirane regije, lokalne zajednice i dr. Kartografska vizuelizacija sa interaktivno koordinisanim višeslojnim prikazom prostornih informacija, omogućava korisnicima perceptivne i kognitivne postupke pri analitičkom rezonovanju. Konteksti rešavanja problema pri planiranju i uređenju prostora zahtevaju vizuelizaciju geopodataka objedinjenih iz različitih izvora, formata, unakrsnih filtriranja, isticanja izbora, vremenskih perioda, načina dizajniranja i dr. Istraživačke i aplikativne potrebe vizije budućih ishoda, na osnovu raspoloživih prostornih podataka, zahtevaju usmerene metode interaktivnosti karata, koje bi omogućile korisnicima da dinamički menjaju vizuelni prikaz geografskih informacija

Informacioni potencijal kartografske vizuelizacije turističkih vrednosti

Savremena informaciona tehnologija omogućava kreativne načine kartografskog prikaza komponenata geoprostora. U procesu planiranja i korišćenje prostora kao osnovnog turističkog resursa, a u sklopu održivog razvоја, neophodno je integrisanje turizma i politike upravljanja lokalnim razvojem. Time se postiže vizija željenog pravca razvoja turizma u sklopu ukupnog ekonomskog, društvenog, kulturnog i ekološkog razvoja lokalne zajednice. Kartografskа vizuelizacijа realnog i virtuelnog geografskog prostora ima podsticajni efekat nа razvoj turizmа. Interesovanja globalnog, otvorenog društva bez granica i veliki protok turista zahteva namenske kartografske proizvode. Karta kao izvor racionalisanih informacija o fenomenima stvarnog sveta predstavlja podršku razvoju turizma. Izrada interaktivnih karata sa pratećim multimedijalnim efekatima, uticaj Interneta i korišćenja aplikacija mobilnih telefona u turističke svrhe, omogućava da se integrišu heterogeni izvori informacija u jedinstven proizvod. Interaktivnost i multimedija omogućava: proširivanje tema i sadržaja turističkih karata, atraktivni prikaz i potrebnu detaljnost turističkog sadržaja. Diverzifikacija kartografskog prikaza, primenom multimedije, omogućava se kroz kreiranje 3D modela, animacije i modela virtuelne i proširene stvarnosti. Time se proširuje značaj turistučkih karata i na delatnost procene i prognoze turističkog razvoja, različite prostorne pokrivenosti - od globalnog preko regionalnog do lokalnog nivoa. Statička 2D karta prelaskom u trodimenzionalnu vizuelizaciju geopodataka i geovirtuelno okruženje, sa orijentacijom i navigacijom proširuje razumevanje geoprostora. Pored izrade karata za turiste, neophodne su i karte koje su namenjene planiranju i regulisanju razvoja turističkih aktivnosti. Time se obezbeđuju prikazi potencijala i perspektiva turističkog razvoja kartirane regije, lokalne zajednice i dr. Kartografska vizuelizacija sa interaktivno koordinisanim višeslojnim prikazom prostornih informacija, omogućava korisnicima perceptivne i kognitivne postupke pri analitičkom rezonovanju. Konteksti rešavanja problema pri planiranju i uređenju prostora zahtevaju vizuelizaciju geopodataka objedinjenih iz različitih izvora, formata, unakrsnih filtriranja, isticanja izbora, vremenskih perioda, načina dizajniranja i dr. Istraživačke i aplikativne potrebe vizije budućih ishoda, na osnovu raspoloživih prostornih podataka, zahtevaju usmerene metode interaktivnosti karata, koje bi omogućile korisnicima da dinamički menjaju vizuelni prikaz geografskih informacija

The influence of carbon black on thermal degradation and gamma irradiation resistance of elastomeric composites based on three network precursors

VI International Conference on Radiation in Various Fields of Research : RAD 2018 : book of abstracts; June 18-22, 2018; Ohrid, Macedoni

The influence of network precursor ratio on the crosslinking and radiation resistance of hybrid elastomeric materials

Materials selected in nuclear processing plants are required to have radiation, thermal and chemical resistance. From experiments on different elastomeric seals materials it was assessed that after a high energy gamma treatment tremendous degradation of properties and compression set exist. Two common network precursors that are used in nuclear power plants are based on ethylene propylene diene rubber (EPDM) and chlorosulfonated polyethylene (CSM). Elastomeric materials based on CSM have good resistance to temperature extremes and chemicals but poor compression set and poor fuel resistance, which is limitation for its sealing application. Blending with other rubbers can improve these properties. Polar CSM rubber can interact with their active functional groups (-SO2Cl) via substitution or condensation reactions. Hydrocarbon origin of EPDM completely saturated chains (without none double bond that imparts an excellent resistance to ozone, weathering, heat, oxidation and polar fluids) are able to absorb more energy without cracking polymeric chain (thus it is classified as radiation-resistant). EPDM rubbers are used in radiation areas for wire coating materials and electrical cables, due to their good resistance to environmental effects. This work aims to the study the influence of network precursor ratio on crosslinking behaviour and radiation resistance of hybrid materials based on CSM/EPDM and high abrasion carbon black particles (iodine adsorption value 82 g/kg). Rubber compounds were prepared using two-roll mill at 40 oC to obtain sheets, which were pressed at 160 oC during 20 minutes at pressure of 16 MPa. Optimal crosslinking time was determined by moving die rheometer (type MDR2000). It was assessed that the optimum curing time of obtained materials increases with increasing content of CSM. The radiation of prepared hybrid materials was carried out using 60Co gamma source with the dose rate 10 kGyh-1 and different total absorbed dose (100, 200 and 400 kGy) at ambient temperature. For blends of two rubbers with dissimilar polarity, distribution of crosslink point can be non-equal through phases. Mechanicals properties and swelling properties were estimated for nonradiated and radiated samples. It was assessed that during radiation process, tensile strength, modulus and hardness and of prepared materials increased, but elongation at break decreased up to dose of 200kGy.VII International Conference on Radiation in Various Fields of Research : RAD 2019 : book of abstracts; June 10-14, 2019; Herceg Novi, Montenegr