21 research outputs found
Problems of the design and construction of slab between floors
Ovaj Älanak daje kratak pregled izgradnje stropnih ploÄa poÄevÅ”i od ploÄe s drvenim gredama do danaÅ”njih armirano betonskih ploÄa (AB). Autori u ovom radu analiziraju neke nove logiÄne poglede po pitanju izgradnje meÄukatnih ploÄa. MeÄukatne ploÄe analiziraju se ne samo u smislu nosivosti, veÄ i u pogledu energetske uÄinkovitosti i sigurnosti tijekom seizmiÄke aktivnosti. Autori nude rjeÅ”enje za izgradnju adaptabilnih velikih stambenih i poslovnih prostora uz moguÄnost postizanja jeftinije i konkurentnije gradnje s istom dobiti (profit) u odnosu na skuplju klasiÄnu gradnju i visoku prodajnu cijenu. Ako se zahtijeva sposobnost da se postigne visoka nosivost s veÄim rasponima, manjom masom i veÄom otpornoÅ”Äu na potrese, lako se može doÄi do zakljuÄka da roÅ”tiljno kasetne AB ploÄe imaju prednost nad drugim rjeÅ”enjima za izgradnju meÄukatnih ploÄa. Pobuda zbog moguÄih denivelacija oslonaca ili torzijske rotacije objekta je praktiÄno moguÄa. To može dovesti do stanja osciliranja ploÄa zbog potresa, Å”to je mnogo manje kod roÅ”tiljno kasetnih ploÄa u odnosu na pune armirano betonske ploÄe. StiroFert, Å”irom svijeta patentirana i provjerena roÅ”tiljno kasetna AB ploÄa, ispunjava sve ove uvjete uz dodatni uvjet: energetska uÄinkovitost. StiroFert je posebno projektirana s konstrukcijski ugraÄenim ekspandiranim polistirenom kao "zarobljenom oplatom" u fazi betoniranja i izgradnje. Ta ista "zarobljena oplata" je moÄna izolacija na najpotrebnijem mjestu: na stropu, s uÄinkom usklaÄivanja temperature zraka izmeÄu poda i stropa.This paper gives a brief overview of building floor slabs starting from slabs with wooden beams to the present reinforced concrete (panels AB). The authors in this paper analyze some new logical views on the issue of building floor slabs. Floor slabs are analyzed not only in terms of capacity, but also in terms of energy efficiency and safety during seismic activity. The authors offer a solution to build adaptive large residential and commercial area with the possibility of achieving cheaper and more competitive construction with the same gain (profit) in relation to the set of the classic construction and a high selling price. If you require the ability to achieve high capacity with longer spans, less weight and less prone to earthquakes, you can easily come to the conclusion that light grate cluster AB boards have an advantage over other solutions for building floor slabs. Excitation due to possible levelling of supports or torsion rotation of the object is practically possible. It can lead to a state of plate due to the earthquake, which is lower in the grate cluster plates compared to full-reinforced concrete slabs. StiroFert, the worldwide patented and tested light cluster grate AB panels, meet all of these requirements with an additional condition: energy efficiency. StiroFert have a specially designed and built structural expanded polystyrene as the "hull trapped" in the construction and concreting. This same "trapped payment" is a powerful insulation on the most needed place: on the ceiling, with the effect of harmonizing air temperature between the floor and the ceiling
Vegetable Production in the Republic of Serbia - Present State and Problems
The aim of the research in this paper is to consider the state and basic trends
of vegetable production in the Republic of Serbia for the period from 2012. to
2020. Therefore, the paper indicates which necessary measures should be taken to
increase the volume of vegetable crop production in our country and improve the
production. In spite of all problems, and owing to significant but insufficiently used
local resources (people) and favourable natural conditions (climate features, soil
and water resources), vegetable production in the Republic of Serbia has a good
opportunity for intensive development. This development has to be accompanied
by the appropriate credit and monetary support, investment and incentives
Feasibility study of determing a risk assessment model for obstructive sleep apnea in children based on local findings and clinical indicators
Objective: To test a feasible and reliable model for diagnosing obstructive sleep apnea (OSA) in children, based on clinically relevant parameters, in comparison to a polysomnography. Methods: A total of 94 children with the suspected underlying OSA were included in the analyses. An association between clinical parameters (modified Mallampati score, tonsil size, adenoid size, age, gender, and body mass index) and apnea-hypopnea index (AHI) obtained following an overnight polysomnography was assessed, and significant variables were incorporated in the logistic regression model. Also, the sensitivity and specificity calculations of the model with the inclusion of ROC curve analysis were performed. Results: All three local clinical parameters were significantly associated with AHI (p<0.001). The most significant correlation with AHI was shown with the modified Mallampati score (r=0.723), following with tonsil size (r=0.673), and adenoid size (r=0.502). The sensitivity of the tested model was 84%, and specificity was 74%. Conclusion: This study derived a model based on the local clinical findings that significantly overlapped with the results of an overnight polysomnography, in diagnosing OSA in children
Karakterizacija razliÄitih obalnih podruÄja Jadrana u kasno proljeÄe
The objective of this study is to analyze the physical and chemical characteristics of three coastal zones of the Adriatic Sea during late spring, and to identify similarities and differences among the
zones. The trophic status of the Southeastern Adriatic-Sea, dominated by the discharge from the Buna/Bojana river delta watersheds, is compared with two other Adriatic regions: the Northwestern Adriatic Sea and the Southwestern Adriatic Sea (Gulf of Manfredonia); the first is dominated by the Po River freshwater discharge and the second is one of the most productive areas of the Southwestern Adriatic.
The areas are influenced by two main Adriatic surface currents: the Eastern Adriatic Current (EAC) that flows north-westward, and the Western Adriatic Current (WAC) that flows south-eastward. The measurements of temperature, salinity, fluorescence, oxygen, nutrients and chlorophyll a in the three areas were collected and compared. The areas showed similar physical and bio-chemical characteristics, despite the Northern
Adriatic is impacted by the Po River runoff and the WAC carries out along the Western Adriatic water rich of nutrients from the northern Italian rivers. The area affected by the Po River discharge showed maximum chlorophyll and nitrogen concentrations within the river plume. Moreover, the
Southwestern Adriatic Sea showed a load of nutrients and organic matter connected to substances coming from the northern Italian rivers (mainly the Po River). Similarly, in the Southeastern
Adriatic-Sea, the Buna/Bojana River discharge contained relatively high values in the regional chlorophyll distribution. The three areas are directly or indirectly linked to river plume dynamics and the associated inorganic and organic inputs determine the trophic state of the areas. In particular, the Southeastern Adriatic Sea was a meso-eutrophic area; despite the most eastern side of the Adriatic was an oligotrophic basin.Cilj ovog istraživanja je analiza fizikalnih i kemijskih svojstava triju obalnih podruÄja Jadrana u kasno proljeÄe i ustanovljenje sliÄnosti i razlika meÄu zonama. TrofiÄki status jugoistoÄnog Jadran-
skog mora, pod utjecajem dotoka slatke vode iz sliva rijeke Bune / Bojane, je u ovom radu usporeÄen s druge dvije jadranske regije: sjeverozapadnim Jadranom i jugozapadnim Jadranom (zaljev Man
-fredonia) u prvom dominiraju pražnjenja rijeke Po, dok je drugi jedno od najproduktivnijih podruÄja jugozapadnog Jadrana.
PodruÄja su pod utjecajem dviju glavnih povrÅ”inskih struja Jadranskog mora: istoÄne jadranske struje (EAC) koja teÄe prema sjeverozapadu i zapadne jadranske struja (WAC) koja teÄe prema jugo-istoku. podaci o izmjerenoj temperaturu, slanosti, fluorescenciji, kisiku, hranjivim tvarima i klorofilu a su sakupljeni i usporeÄeni za sva tri podruÄja. Istraživana podruÄja su pokazala sliÄne fiziÄke
i bio-kemijske karakteristike, unatoÄ Äinjenici da je sjeverni Jadran pod utjecajem dotoka rijeke Po, a zapadna jadranska struja (WAC) nosi duž zapadnog Jadrana vodu bogatu hranjivim tvarima iz
talijanskih rijeka na sjeveru. PodruÄje pogoÄeno dotokom rijeke Po pokazalo je maksimum koncentracije klorofila i duÅ”ika unutar rijeka. Å toviÅ”e, u jugozapadnom Jadranu koliÄina hranjivih tvari i
organske tvari je povezana s tvarima koje dolaze iz sjevernih talijanskih rijeka (uglavnom rijeke po).
SliÄno tome, u jugoistoÄnom dijelu jadranskog mora, dotok rijeke Bune / Bojane sadržavao je relativno visoke vrijednosti klorofila na nivou regionalne distribucije. Tri podruÄja su izravno ili
neizravno povezana s dinamikom rijeÄnih perjanica, te organskim i anorganskim rijeÄnim unosom koji odreÄuje trofiÄko stanje podruÄja. Konkretno, jugoistoÄno Jadransko more je mezo-eutrofiÄno podruÄje; unatoÄ veÄoj istoÄnoj strani Jadrana koij je bio oligotrofan bazen
Prostorna raspodjela fizikalnih, kemijskih i bioloŔkih oceanografskih karakteristika, fitoplanktona, hranjivih tvari i otopljene obojane organske materije (CDOM) u Bokokotorskom zaljevu na Jadranu
The temporal variations of temperature, salinity, fluorescence, dissolved oxygen concentration, Coloured Dissolved Organic Matter (CDOM) and of chemical (nutrients, chlorophyll a) and biological (phytoplankton composition) parameters in the Boka Kotorska Bay were observed during two periods. CDOM regulates the penetration of UV light into the sea and therefore plays an important role in many hydrological and biogeochemical processes in the sea surface layer including primary productivity. In the framework ADRICOSM-STAR it was possible to investigate the Boka Kotorska Bay during May and June 2008 in order to increase an understanding of optical and chemical characteristics and their evolution during these periods. In both periods station KO (located furthest from the open sea) presented different physical, chemical and biological characteristics with respect to the other stations inside the Boka Kotorska Bay. A positive correlation was found between CDOM and chlorophyll a (R = 0.7, P < 0.001, n = 15) and this implies that in this area, similarly to the open sea, the primary source of CDOM should be the biological production from phytoplankton. This is probably due to the fact that the rivers entering the Boka Kotorska Bay are not severely impacted by man.U Bokokotorskom zaljevu su mjerene vremenske promjene temperature, saliniteta, fluorescencije, koncentracije otopljenog kisika, obojene otopljene organske materije (CDOM) i kemijskih (hranjive soli, klorofila) i bioloÅ”kih (sastav fitoplanktona) parametara tijekom dva razdoblja (svibanj i lipanj 2008. godine). CDOM odreÄuje prodiranje UV svjetlosnih zraka u more i stoga igra vrlo važnu ulogu u mnogim hidroloÅ”kim i biogeokemijskim procesima u povrÅ”inskom sloju mora koji ukljuÄuje primarnu produkciju. Unutar ADRICOSM-STAR projekta, bilo je moguÄe istražiti Bokokotorski zaljev tijekom svibnja i lipnja 2008. godine radi poveÄanja razumijevanja optiÄkih i kemijskih karakteristika i njihovog razvoja kroz ova razdoblja. Zbog dotoka krÅ”kih rijeka i smanjenja razmjene s otvorenim morem, u oba razdoblja postaja KO (smjeÅ”tena najdalje od otvorenog mora) je pokazala razliÄite fizikalne, kemijske i biolo{ke karakteristike u odnosu na postaje unutar Bokokotorskog zaljeva. PronaÄena je pozitivna korelacija izme|u CDOM i klorofila a (R = 0.7, P < 0.001, n = 15) {to upuÄuje na to da bi u ovom podruÄju, sliÄno otvorenom moru, primarni izvor CDOM trebao biti bioloÅ”ka produkcija od fitoplanktona. To je vjerojatno zbog toga Å”to dotoci rijeka u Bokokotorskom zaljevu nisu ozbiljnije ugroženi ljudskim djelovanjem
Primjena bioloÅ”kih markera u identifikaciji zagaÄivaÄa naftnog tipa u recentnim sedimentima - aluvijalna formacija rijeke Dunav, Rafinerija nafte PanÄevo
The purpose of this paper was to examine to which extent the abundance and distribution of certain biological markers may be used for the identification of oil-type pollutants in recent sediments and ground waters. The samples were taken from the area of the Oil Refinery PanÄevo (alluvial formation of the Danube River). The organic matter of the investigated samples was isolated using an extraction method with chloroform. The group composition and usual biological markers were analyzed in the obtained extracts. n-Alkanes and acyclic isoprenoids, pristane and phytane were analyzed using gas chromatographie (GC) analysis of saturated hydrocarbons. Polycyclic alkanes of the sterane and terpane type were analyzed using gas chromatography-mass spectrometry (GC-MS), i.e. by analyzing the carbamide non-adduct of the total alkane fraction (Single Ion Monitoring SIM-technique). The obtained results indicate that n-alkanes can be used for the identification of oil-type pollutants (for example, if the oil-pollutant is biodegraded or present in very low concentrations), and steranes and triterpanes can be used as very reliable indicators of oil-type pollution in recent sediments and ground waters.Cilj ovog rada bio je da se utvrdi u kolikoj mjeri se obilnosti i raspodjele pojedinih bioloÅ”kih markera mogu upotrijebiti za identifikaciju zagaÄivaÄa naftnog tipa u recentnim sedimentima i podzemnim vodama. Ispitivani su uzorci sa lokaliteta Rafinerije nafte PanÄevo (aluvijalna formacija rijeke Dunav). Organska supstanca ispitivanih uzoraka izolovana je ekstrakcijom pomoÄu hloroforma. U dobivenim ekstraktima odreÄen je grupni sastav i analizirani su najpoznatiji bioloÅ”ki markeri. n-Alkani i acikliÄni izoprenoidni alkani, pristan i fitan, analizirani su gasnohromatografskom (GC) analizom frakcije zasiÄenih ugljovodonika, a policikliÄni alkani tipa sterana i triterpana primjenom gasnohromato-grafsko-masenospekrometrijske (GC-MS) analize karbamidnog neadukta ukupnih alkana (Single Ion Monitoring SIM, tehnika), Dobiveni rezultati pokazali su da u sluÄajevima kada se n-alkani ne mogu upotrijebiti u identifikaciji zagaÄivaÄa naftnog tipa (na primjer, ukoliko je naftni zagaÄivaÄ biodegradovan i/ili prisutan u veoma niskim koncentracijama), sterani i triterpani mogu poslužiti kao veoma pouzdani indikatori prisustva ovog zagaÄivaÄa u recentnim sedimentima i podzemnim vodama
Effect of Adsorption Processing of Solvent Base Oils by Activated Bentonite
Solvent base oils of group API I contain larger quantities of aromatic compounds and sulfur, as compared to base oils of higher quality groups. Processing of base oils by commercial clays is performed in order to reduce the content of undesirable compounds, improving the color and oxidation stability. Commercial clays are based on aluminosilicates with a large specific surface area and developed porosity. Bentonite has good adsorption characteristics, which can be further improved by various methods of modification. In this paper, adsorption processing of solvent base oils is derived by acid-activated bentonite and commercial clay. The structural composition of starting oil and refined solvent oil (content of aromatics, paraffins, naphtenes and sulfur) is determined by following methods: IEC 590, UV, IP 346 and BAS ISO 20846. The results showed that processing of a solvent oil by activated bentonite leads to change of structural composition, similar to a change achived by processing with commercial clay
Supplementary data for article: VilipiÄ, J.; NovakoviÄ, I.; StanojkoviÄ, T.; MatiÄ, I.; Å egan, D.; KljajiÄ, Z.; SladiÄ, D. Synthesis and Biological Activity of Amino Acid Derivatives of Avarone and Its Model Compound. Bioorganic and Medicinal Chemistry 2015, 23 (21), 6930ā6942. https://doi.org/10.1016/j.bmc.2015.09.044
Supplementary material for: [https://doi.org/10.1016/j.bmc.2015.09.044]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1997]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3438