39 research outputs found
Efekat suŔe 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 razliÄitim stresnim uslovima spoljaÅ”nje sredine. Cilj ovih istraživanja je bio da se ispita efekat suÅ”e na vodni režim i rastenje sorte kvinoje KVL52 u kontrolisanim uslovima gajenja. Dobijeni rezultati ukazuju da su reakcije kvinoje na suÅ”u bazirane na mehanizmu izbegavanja suÅ”e: redukciji transpiracije i održanju usvajanja vode. Transpiracija je redukovana zahvaljujuÄi opadanju provodljivosti stoma i redukciji lisne povrÅ”ine. Ovi rezultati mogu biti od praktiÄnog znaÄaja za testiranje moguÄnosti gajenja kvinoje kao kulture koja je otporna na suÅ”u 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 āage-friendly citiesā, 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 postojeÄem svijetu druÅ”tvenih i demografskih promjena koje neprestano mijenjaju i poveÄavaju potražnju za smjeÅ”tajem, iskoriÅ”tavanje postojeÄeg graÄevinskog fonda za razvoj novih stambenih prostora mogao bi postati održivo rjeÅ”enje problema prenapuÄenosti gradova. Konverzija zastarjelih zgrada, koje su izgubile svoju primarnu funkciju, u stambene objekte, jedna je od postojeÄih metoda za revitalizaciju visoko-urbaniziranih podruÄja. BuduÄi da je konverzija samo jedna od moguÄih metoda urbane obnove, jer se vrlo Äesto primijenjuju radikalnije mjere demoliranja zgrada i konverzije zemljiÅ”ta, potrebno je analizirati i kvalitetu i prikladnost ovoga pristupa. U radu se naglaÅ”avaju prednosti implementiranja konverzije zgrada kad se radi o smjeÅ”taju te se istražuju opÄe karakteristike postojeÄih 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 Ā°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. Ā© 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 ā 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 ureaformaldehydeāMMT 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 turistiÄkih vrednosti
Savremena informaciona tehnologija omoguÄava kreativne naÄine kartografskog prikaza komponenata geoprostora. U procesu planiranja i koriÅ”Äenje prostora kao osnovnog turistiÄkog resursa, a u sklopu održivog razvŠ¾ŃŠ°, neophodno je integrisanje turizma i politike upravljanja lokalnim razvojem. Time se postiže vizija željenog pravca razvoja turizma u sklopu ukupnog ekonomskog, druÅ”tvenog, kulturnog i ekoloÅ”kog razvoja lokalne zajednice. KartografskŠ°
vizuelizacijŠ° realnog i virtuelnog geografskog prostora ima podsticajni efekat nŠ° razvoj turizmŠ°.
Interesovanja globalnog, otvorenog druŔtva bez granica i veliki protok turista zahteva namenske kartografske proizvode. Karta kao izvor racionalisanih informacija o fenomenima stvarnog
sveta predstavlja podrÅ”ku razvoju turizma. Izrada interaktivnih karata sa prateÄim multimedijalnim efekatima, uticaj Interneta i koriÅ”Äenja aplikacija mobilnih telefona u turistiÄke svrhe,
omoguÄava da se integriÅ”u heterogeni izvori informacija u jedinstven proizvod. Interaktivnost
i multimedija omoguÄava: proÅ”irivanje tema i sadržaja turistiÄkih karata, atraktivni prikaz i
potrebnu detaljnost turistiÄkog sadržaja. Diverzifikacija kartografskog prikaza, primenom multimedije, omoguÄava se kroz kreiranje 3D modela, animacije i modela virtuelne i proÅ”irene stvarnosti. Time se proÅ”iruje znaÄaj turistuÄkih karata i na delatnost procene i prognoze turistiÄkog
razvoja, razliÄite prostorne pokrivenosti - od globalnog preko regionalnog do lokalnog nivoa.
StatiÄka 2D karta prelaskom u trodimenzionalnu vizuelizaciju geopodataka i geovirtuelno
okruženje, sa orijentacijom i navigacijom proŔiruje razumevanje geoprostora. Pored izrade
karata za turiste, neophodne su i karte koje su namenjene planiranju i regulisanju razvoja
turistiÄkih aktivnosti. Time se obezbeÄuju prikazi potencijala i perspektiva turistiÄkog razvoja kartirane regije, lokalne zajednice i dr. Kartografska vizuelizacija sa interaktivno koordinisanim viÅ”eslojnim prikazom prostornih informacija, omoguÄava korisnicima perceptivne i
kognitivne postupke pri analitiÄkom rezonovanju. Konteksti reÅ”avanja problema pri planiranju i ureÄenju prostora zahtevaju vizuelizaciju geopodataka objedinjenih iz razliÄitih izvora,
formata, unakrsnih filtriranja, isticanja izbora, vremenskih perioda, naÄina dizajniranja i dr.
IstraživaÄke i aplikativne potrebe vizije buduÄih ishoda, na osnovu raspoloživih prostornih
podataka, zahtevaju usmerene metode interaktivnosti karata, koje bi omoguÄile korisnicima
da dinamiÄki 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
Informacioni potencijal kartografske vizuelizacije turistiÄkih vrednosti
Savremena informaciona tehnologija omoguÄava kreativne naÄine kartografskog prikaza komponenata geoprostora. U procesu planiranja i koriÅ”Äenje prostora kao osnovnog turistiÄkog resursa, a u sklopu održivog razvŠ¾ŃŠ°, neophodno je integrisanje turizma i politike upravljanja lokalnim razvojem. Time se postiže vizija željenog pravca razvoja turizma u sklopu ukupnog ekonomskog, druÅ”tvenog, kulturnog i ekoloÅ”kog razvoja lokalne zajednice. KartografskŠ°
vizuelizacijŠ° realnog i virtuelnog geografskog prostora ima podsticajni efekat nŠ° razvoj turizmŠ°.
Interesovanja globalnog, otvorenog druŔtva bez granica i veliki protok turista zahteva namenske kartografske proizvode. Karta kao izvor racionalisanih informacija o fenomenima stvarnog
sveta predstavlja podrÅ”ku razvoju turizma. Izrada interaktivnih karata sa prateÄim multimedijalnim efekatima, uticaj Interneta i koriÅ”Äenja aplikacija mobilnih telefona u turistiÄke svrhe,
omoguÄava da se integriÅ”u heterogeni izvori informacija u jedinstven proizvod. Interaktivnost
i multimedija omoguÄava: proÅ”irivanje tema i sadržaja turistiÄkih karata, atraktivni prikaz i
potrebnu detaljnost turistiÄkog sadržaja. Diverzifikacija kartografskog prikaza, primenom multimedije, omoguÄava se kroz kreiranje 3D modela, animacije i modela virtuelne i proÅ”irene stvarnosti. Time se proÅ”iruje znaÄaj turistuÄkih karata i na delatnost procene i prognoze turistiÄkog
razvoja, razliÄite prostorne pokrivenosti - od globalnog preko regionalnog do lokalnog nivoa.
StatiÄka 2D karta prelaskom u trodimenzionalnu vizuelizaciju geopodataka i geovirtuelno
okruženje, sa orijentacijom i navigacijom proŔiruje razumevanje geoprostora. Pored izrade
karata za turiste, neophodne su i karte koje su namenjene planiranju i regulisanju razvoja
turistiÄkih aktivnosti. Time se obezbeÄuju prikazi potencijala i perspektiva turistiÄkog razvoja kartirane regije, lokalne zajednice i dr. Kartografska vizuelizacija sa interaktivno koordinisanim viÅ”eslojnim prikazom prostornih informacija, omoguÄava korisnicima perceptivne i
kognitivne postupke pri analitiÄkom rezonovanju. Konteksti reÅ”avanja problema pri planiranju i ureÄenju prostora zahtevaju vizuelizaciju geopodataka objedinjenih iz razliÄitih izvora,
formata, unakrsnih filtriranja, isticanja izbora, vremenskih perioda, naÄina dizajniranja i dr.
IstraživaÄke i aplikativne potrebe vizije buduÄih ishoda, na osnovu raspoloživih prostornih
podataka, zahtevaju usmerene metode interaktivnosti karata, koje bi omoguÄile korisnicima
da dinamiÄki menjaju vizuelni prikaz geografskih informacija
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