Experimental verification of mathematical model of the heat transfer in exhaust system

A catalyst convertor has maximal efficiency when it reaches working tempera-ture. In a cold start phase efficiency of the catalyst is low and exhaust emissions have high level of air pollutants. The exhaust system optimization, in order to de-crease time of achievement of the catalyst working temperature, caused reduction of the total vehicle emission. Implementation of mathematical models in devel-opment of exhaust systems decrease total costs and reduce time. Mathematical model has to be experimentally verified and calibrated, in order to be useful in the optimization process. Measurement installations have been developed and used for verification of the mathematical model of unsteady heat transfer in ex-haust systems. Comparisons between experimental results and the mathematical model are presented in this paper. Based on obtained results, it can be concluded that there is a good agreement between the model and the experimental results

Indicators of tourism development of the Serbian danube region

Protected natural area in the Danube region covers 107,200 hectares and includes two national parks, two nature parks, one place of outstanding natural beauty, five special natural reserves, twenty-five nature monuments, and two sites of international significance included in the Ramsar list. However, only 140 immovable and 374 movable cultural objects are officially registered. There are 31 cultural objects of exceptional importance and national significance and 89 objects of great importance and regional significance. The objects with this status are protected by the state. Two sites are on the preliminary UNESCO World Heritage list. This paper discusses the potential of tourism industry in the Serbian Danube Region and the prospects of its further development. We outline the current state of tourism industry and describe the geographical location of the region, its natural and anthropogenic resources, and accommodation capacities. We analyse such data as the number of tourists and the number of overnight stays by municipalities in 2016, and the average length of stay. The indicators used are the functionality coefficient, the capacity utilization and the intensity of functionality. The conclusion is drawn that the tourism potential of the Serbian Danube Region is not fully realized and that its development should be at a much higher level, given the increasingly important role of the region as a major tourist destination in Serbia

One–pot synthesis of hydrophobic hydroxyapatite nano particles

A highly hydrophobic oleic acid functionalized hydroxyapatite nanoparticles were obtained by the solvothermal method. Water solutions of reactants were added in mixture of oleic acid, triethanolamine and ethanol, which was then treated in Teflon lined autoclave. The chemical composition, size and morphology of as obtained particles were determined using XRD, FT IR, FE SEM and LD PSA. In addition, sintering behaviour and microstructure of prepared material were also examined

Nutritivna vrednost kukuruznog stočnog brašna u ishrani pilića u tovu

One of the by-products of corn processing which can successfully be used in poultry nutrition is livestock meal. In this trial corn meal was investigated, meal in two form: non-extruded (T1 and T2) and extruded (T3 and T4) as a replacement of cracked corn (K) in the amount of 100% (T1 and T3) and 50% (T2 and T4). Investigation was carried out in 4 repetitions, 75 chickens of Arbor Acres x Ross 308 hybrid in each group. Trial lasted 42 days. Chickens were fed three standard mixtures (starter, grower and finisher). Investigation demonstrated that group of chickens of treatment T3 realized the best final body masses (2254g), followed by chickens in treatment T4 (2173g), chickens of group T2 (2112g), K group (2106 g), and the worst results were established in chickens of group T1 (2103g). It was established that differences in final body mass of chickens from group T3 in relation to chickens from groups T1, T2, T4 and were statistically highly significant (P (lt) 0,001). Statistically significant differences (P (lt) 0,05) were established between body masses of chickens from group T4 in relation to T1, T2 and K group. Mortality of chickens was as followes: K-3,64%, T1- 2,50%, and T2-5,00%, T3-6,39%, and T4-3,33%. Feed conversion in all investigated groups was almost identical (K-1,91; T2-,93; T3-1,93; T4-1,94) with the exception of T1 with 1,97. In regard to production index (PI), the best results were realized by group of chickens T3 (261), followed by chickens T4 (258), K (253), and the worst results were established in chickens of groups T1 (248) and T2 (248).U radu je dat efekat primene neekstrudiranog (T1 i T2) i ekstrudiranog (T3 i T4) kukuruznog stočnog brašna u ishrani brojlerskih pilića. U smešama kukuruz (K) je zamenjen kukuruznim stočnim brašnom u iznosu 50% (T2 i T4) i 100% (T1 i T3). Ogled je trajao 42 dana po sistemu 5 x 4 (5 tretmana x 4 ponavljanja). U svakom tretmanu je bilo po 300 pilića. Ishrana je bila ad libitum sa tri smeše: starter sa 23,30% SP i 12,78 MJ/kg ME, grover sa 20,30% SP i 13,10 MJ/kg ME, i finišer 17,70% SP i 13,25 MJ/kg ME. Rezultati ispitivanja su bili sledeći: telesne mase K-2106g, T1-2103g, T2-2112g, T3-2254g, i T4-2173g; dnevni prirast K-50,13g, T1-50,08g, T2- 50,29g, T3-53,66g, i T4-51,73g; mortalitet pilića K-3,64%, T1-2,50%, T2- 5,00%, T3-6,39%, i T4-3,33%; Konverzija hrane K-1,91 kg/kg, T1-1,97 kg/kg, T2-1,93 kg/kg, T3-1,93 kg/kg, i T4-1,94 kg/kg. Pokazalo se da su razlike u završnoj telesnoj masi pilića iz T3, u odnosu na T1, T2, T4 i K grupe, bile statistički visoko značajne (P (lt) 0,001). Utvrđene su statistički značajne razlike (P (lt) 0,05) između telesnih masa grupe pilića T4 u odnosu na T1, T2 i K grupe. Randmani su bili ujednačeni po grupama, a razlike u sadržaju abdominalne masti u trupovima su bile minimalne ali nešto niže kod petlića i kojica grupe T1 i petlića T2. Razlike su bile su statistički značajne

Electron-ion recombination of Si IV forming Si III: Storage-ring measurement and multiconfiguration Dirac-Fock calculations

The electron-ion recombination rate coefficient for Si IV forming Si III was measured at the heavy-ion storage-ring TSR. The experimental electron-ion collision energy range of 0-186 eV encompassed the 2p(6) nl n'l' dielectronic recombination (DR) resonances associated with 3s to nl core excitations, 2s 2p(6) 3s nl n'l' resonances associated with 2s to nl (n=3,4) core excitations, and 2p(5) 3s nl n'l' resonances associated with 2p to nl (n=3,...,infinity) core excitations. The experimental DR results are compared with theoretical calculations using the multiconfiguration Dirac-Fock (MCDF) method for DR via the 3s to 3p n'l' and 3s to 3d n'l' (both n'=3,...,6) and 2p(5) 3s 3l n'l' (n'=3,4) capture channels. Finally, the experimental and theoretical plasma DR rate coefficients for Si IV forming Si III are derived and compared with previously available results.Comment: 13 pages, 9 figures, 3 tables. Accepted for publication in Physical Review

Analysis of lymphocyte glucocorticoid receptor phosphorylation in healty subjets and patients with current episode of depressive disorder

Depresivni poremećaj (DP) je multifaktorijalno oboljenje, široko rasprostranjeno u svetu, i rasvetljavanje mehanizama koji su u osnovi ovog poremećaja predstavlja jedan od najvećih izazova biomedicinskih istraţivanja današnjice. Narušena funkcija hipotalamo-hipofizno-adrenalne (HHA) ose, kao i signalizacija preko glukokortikoidnog receptora (GR), čest su nalaz kod pacijenata sa DP-om. Takođe, određeni stepen disfunkcije HHA ose i samog GR-a uočavaju se i kod zdravih ljudi i pretpostavlja se da to predstavlja jedan od faktora rizika za razvoj kliničke depresije. S druge strane, uspešno lečenje pacijenata sa depresijom, praćeno je normalizacijom aktivnosti HHA ose i funkcije GR-a. GR je ligand-zavisan transkripcioni faktor, koji nakon vezivanja glukokortikoida (krajnjih produkata aktivnosti HHA ose) prelazi iz citoplazme u jedro gde reguliše ekspresiju velikog broja gena. Vaţan način regulacije funkcije GR-a postiţe se njegovom fosforilacijom koja je posredovana aktivnošću kinaza, koje se aktiviraju u odgovoru na različite ćelijske signale. Fosforilacija GR-a na serinu 211 (S211) stimuliše ulazak receptora u jedro i generalno se smatra biomarkerom njegove povećane transkripcione aktivnosti, dok je za fosforilaciju GR-a na serinu 226 (S226), koja je posredovana c-Jun N-terminalnim kinazama (eng. c-Jun N-terminal kinases, JNK), pokazano da inhibira njegovu transkripcionu aktivnost i stimuliše izlazak GR-a iz jedra u citoplazmu. Među genima stimulisanim glukokortikoidima su GILZ (eng. glucocorticoid-induced leucine zipper, GILZ), vaţan posrednik anti-inflamatornih efekata GR-a, i FKBP5 (eng. FK506 binding protein 5, FKBP5), koji ima vaţnu ulogu u ograničavanju glukokortikoidne signalizacije u ćeliji, sprečavajući translokaciju GR-a iz citoplazme u jedro...Major depressive disorder (MDD) is a multifactorial illness that a ffects people across the globe and u derstanding mechanisms underlying this disorder represents a major challenge of biomedical research today. One of the most consistent findings among patients with MDD is dysfunctional hypothalamic – pituitary – adrenal (HPA) axis, caused by altered function of the glucocorticoid receptor (GR). In healthy population, individuals with impaired HPA axis and GR function are also observed, and these features are believed to represent increased risk factors for depression . On the o ther hand, successful antidepressant treatments ameliorate many of the neuroendocrine disturbances observed in depression . The GR is ligand - activated transcriptional factor that apon glucocorticoid binding (glucocorticoids are end products of HPA axis acti vity) translocate from the cytoplasm to the nucleus where it modulates the expression of wide variety of genes. Phoshor y lation of the GR, mediated by activity of diverse cellular kinases, is imprtant way of regulating GR function. The GR phosphorylation at S211 promotes GR translocation to the nucleus and enhances its transcriptional activity , while GR phosphorylation at S226, mediated by c - Jun N - terminal kinases (JNK), inhibits its transcriptional activity and promotes GR nuclear export. Some of m yriad of genes whose expression is stimu late d by the GR are glucocorticoid - induced leucine zipper (GILZ), an important mediator of glucocorticoid anti - imflamatory actions, and FK506 binding protein 5 (FKBP5), which is a part of an intracellular ultra - short negative feedback loop for GR activity..

The effects of ameliorative afforestations in Grdelička gorge and Vranjska valley

Свакодневно увећавање светског становништва чија потреба за производњом хране и местом за становање непрестано расте и захтева проширивање територије најчешће на рачун крчења шума, доводи до деградације животне средине у свим сегментима. Голети настале обешумљавањем су веома еродибилна станишта чему доприноси одсуство влаге, изражена купираност терена са великим нагибима, геолошка подлога, неповољна хидрографска мрежа и начин коришћења земљишта као један од значајних фактора деградације. Пошумљавање је метода успостављања шумске вегетације на обешумљеним подручјима чиме се земљиште успешно и дугорочно штити од деградације и притом се обезбеђују вишеструке користи које се могу исказати мелиоративним ефектима пошумљавања. Мелиоративни ефекти противерозионих пошумљавања су исказани вредновањем утицаја на процес педогенезе кроз анализу физичких и хемијских особина земљишта. Обогаћивање биодиверзитета је вредновано анализом односа флористичког састава и одређених фактора средине...Every day, the world's population with increasing need for food production and housing is growing and tending to expand territory in account of deforestation, which leads to the degradation of the environment in all aspects. Bare lands occur as а result of deforestation. Such habitats are highly erodable thanks to the lack of moisture, steep slopes, bedrock, unfavorable hydrographic network and land use as one of the main factors of degradation. Afforestation is a method of establishing forest vegetation on deforested land areas to provide longterm degradation protection and thereby achieve the multiple benefits that can be expressed by ameliorative effects of afforestation. Ameliorative effects of afforestation are presented by evaluation of the impact of afforestation on the process of pedogenesis through analysis of the physical and chemical properties of soil. Enrichment of biodiversity is evaluated by analyzing the relationship of the floristic composition and certain environmental factors. Effect in erosion control is evaluated by estimation of soil loss according to Gavrilovic, in years 1967. and 2009..

Development of the computer-aided process planning (CAPP) system for polymer injection molds manufacturing

Beginning of production and selling of polymer products largely depends on mold manufacturing. The costs of mold manufacturing have significant share in the final price of a product. The best way to improve and rationalize polymer injection molds production process is by doing mold design automation and manufacturing process planning automation. This paper reviews development of a dedicated process planning system for manufacturing of the mold for injection molding, which integrates computer-aided design (CAD), computer-aided process planning (CAPP) and computer-aided manufacturing (CAM) technologies

Measurement and analysis of vibrations of the axial-flow compressor caused by inlet flow instability during the flight of aircraft

U radu je prezentovan praktičan primer merenja i analize vibracija na prva dva stepena aksijalnog kompresora sa namerom da se proceni povezanost između poremećene ulazne struje vazduha i pojave otcepljenja strujnica od lopatica kompresora. Poremećenost ulazne struje vazduha je ispitivana tokom različitih režima leta aviona sa maksimalnim potiskom, pod pretpostavkom da postoji nesimetrično strujanje vazduha kroz dvostruki uvodnik i da ono ima uticaj na pojavu vibracija kompresora. Prikazano je merenje vibracija na avionu Galeb G-2 sa motorom Rolls Royce Viper Mk22-6 sa ciljem da se prepozna i definiše minimum neophodnih podataka koji bi ukazali na potencijalnu poremećenu struju vazduha kroz kompresor, kao posledicu nejednake raspodele vazdušne struje u uvodniku. Efikasnost ove metodologije merenja predstavljena je korišćenjem Furijeovih transformacija. Predložena metodologija merenja i analize može se sprovoditi na različitim tipovima aviona u cilju istraživanja pojave otcepljenja strujnica i pumpanja kompresora.This paper presents a practical example of the measurement and analysis of vibrations in the first two stages of the axial-flow compressor with intention to estimate a connection between inlet air flow distortions and appearance of stalling of the compressor blades. The inlet air flow distortions were tested during different regimes of the aircraft flight with a maximum thrust, with an assumption that the asymmetry of air flow through the twin-inlets existed and had effect on vibrations of the compressor. The paper shows the measurement of vibrations on the Galeb G-2 aircraft powered by the Rolls Royce Viper Mk22-6 engine with the aim to recognize and define the minimum necessary data for detection of the potential distorted air flow through the compressor, as consequences of an unequal air flow distribution in the inlets. The detection capability of this methodology of measurement is presented using the fast Fourier transform (FFT). The proposed methodology of measurement and analysis can be implemented in different types of aircraft in order to research the occurrence of stall and surge

Evaluación de la inuencia del ciclo vital en la producción de los productos de carne de cerdo sobre el medio ambiente

The objective of this paper was to assess the environmental performance of the production of pork products in Serbia. Life cycle assessment calculations have been performed to identify and quantify the environmental impacts from a cradle-to-grave perspective covering four subsystems: ‘pig housing farm’, ‘slaughterhouse’, ‘meat processing plant’ and ‘waste and waste water treatment’. Structured survey has been conducted in order to collect life cycle inventory input data. Six environmental impact potentials were calculated in this study: global warming potential, acidification potential, eutrophication potential, ozone layer depletion, photochemical smog and human toxicity. The global warming potential associated with the production of 1 kg of pork products is 9.04 kg CO2eq. Acidification potential within the pork meat chain is 9.874 x 10-3 kg SO2eq while the eutrophication potential is 0.0151 kg PO4eq. The largest contributor to the environmental profile of meat production within the pork meat chain is the production of feed and manure management. Contributions of the processing plants are mainly due to water and energy requirement and use of refrigerants in the cold chain.Cilj je ovog rada bio procijeniti utjecaj proizvodnje proizvoda od svinjetine u Srbiji na okoliš. Izračuni za procjenu životnog ciklusa provedeni su kako bi identi.cirali i kvanti.cirali utjecaj na okoliš po načelu „od kolijevke do groba“, koji obuhvaća četiri podsustava: ‘farmu za uzgoj svinja’, ‘klaonicu’, pogone za preradu mesa’ i ‘pogon za zbrinjavanje otpada i otpadnih voda’. U cilju prikupljanja ulaznih podataka inventara životnog ciklusa provedeno je strukturirano istraživanje. Navedenim smo istraživanjem procijenili šest potencijalnih utjecaja na okoliš: potencijal globalnog zatopljenja, potencijal akiseljavanja, potencijal eutro.kacije, potencijal razaranja ozona, potencijal stvaranja fotokemijskog smoga i toksičnost za čovjeka. Potencijal globalnog zatopljenja povezan s proizvodnjom 1 kg proizvoda od svinjetine iznosi 9,04 kg CO2Eq. Potencijal zakiseljavanja unutar lanca svinjskog mesa iznosi 9,874 x 10-3 kg SO2Eq, a potencijal eutro.kacije 0,0151 kg PO4Eq. Na okoliš u lancu svinjskog mesa tijekom proizvodnje najviše utječu proizvodnja stočne hrane i upravljanje gnojivom. Utjecaj pogona za preradu uglavnom se odnosi na zahtjeve za vodu i energiju te uporabu rashladnih sustava u hladnom lancu.Ziel dieser Arbeit war es, den Ein!uss der Herstellung von Schweine!eischprodukten in Serbien auf die Umwelt zu bewerten. Berechungen für die Bewertung des Lebenszyklus wurden vorgenommen, um die Umweltein!üsse zu identi.zieren und quanti.zieren, nach dem Grundsatz „von der Wiege bis zum Grabe“, der vier Teilsysteme umfasst: ‘Schweinezuchtbetrieb’, ‘Schlachtbetrieb’, ‘Fleischverarbeitungsbetrieb’ und ‘Abfall- und Abwasserentsorgungsbetrieb’. Um Eingangsdaten über das Lebenszyklusinventar zu sammeln, wurde eine strukturierte Untersuchung durchgeführt. In der genannten Untersuchung haben wir sechs potentielle Umweltein!üsse ausgewertet: Potential der globalen Erwärmung, Potential der Versauerung, Potential der Eutrophierung, Potential der Ozonzerstörung, Potential der Entstehung von Sommersmog und Toxizität für den Menschen. Das Potential der globalen Erwärmung, das mit der Herstellung von 1 kg Schweine!eischprodukten verbunden ist, beträgt 9,04 kg CO2Eq. Das Potential der Versauerung innerhalb der Schweine!eischkette beläuft sich auf 9,874 x 10-3 kg SO2Eq und das Potential der Eutrophierung auf 0,0151 kg PO4Eq. Der größte Ein!uss in der Fleischkette während der Herstellung haben die Produktion von Viehfutter und die Verwaltung von Düngemitteln. Die Auswirkung des Verarbeitungsbetriebs bezieht sich größtenteils auf die Wasser- und Energieanforderungen und den Einsatz von Kühlmitteln in der Kühlkette.Obiettivo di questo studio č quello di valutare l’incidenza della produzione dei prodotti di carne suina sull’ambiente in Serbia. I rilevamenti per la valutazione del ciclo vitale sono stati eseguiti ai .ni dell’identi.cazione e della quanti.cazione dell’incidenza sull’ambiente in base al principio “dalla culla alla tomba”, comprendente quattro sottosistemi: “impianto d’allevamento di suini”, “macello/mattatoio”, “impianto di lavorazione delle carni” e “impianto per lo smaltimento dei ri.uti e delle acque reue”. Ai .ni della raccolta dei dati d’ingresso dell’inventario del ciclo vitale animale, č stata eseguita una ricerca strutturata. Mediante detta ricerca, abbiamo valutato sei potenziali fattori d’incidenza sull’ambiente: il potenziale di riscaldamento globale, il potenziale di acidi.cazione, il potenziale di eutro.zzazione, il potenziale di degrado dell’ozono, il potenziale di creazione dello smog fotochimico e di tossicitŕ per l’uomo. Il potenziale di riscaldamento globale legato alla produzione di 1 kg di prodotti di carne suina č pari a 9,04 kg CO2Eq. Il potenziale di acidicazione nell’ambito della catena di produzione della carne suina č pari a 9,874 x 10-3 kg SO2Eq, mentre il potenziale di eutro.zzazione čpari a 0,0151 kg PO4Eq. Sull’ambiente, nel nell’ambito della catena della carne suina, nel corso della produzione, incidono maggiormente la produzione del mangime e la gestione del concime. L’incidenza dell’impianto di lavorazione delle carni si riferisce in prevalenza alle esigenze di acqua ed energia e all’uso di sistemi di ra#reddamento nella catena del freddo.El objetivo de este trabajo fue evaluar la inuencia de la producción de los productos de carne de cerdo en Serbia sobre el medio ambiente. Los cálculos para evaluar el ciclo vital fueron hechos para identi.car y cuanti.car la inuencia sobre el medio ambiente según el principio ‘’de la cuna a la tumba’’, el cual incluye cuatro subsistemas: ‘la planta para crianza de cerdos’, ‘el matadero’, la planta para el procesamiento de carne’ y ‘la planta para deposito de residuos y aguas residuales’. Fue hecha una investigación estructurada el .n de recoger los datos de entrada del inventario del ciclo vital fue hecha una. Con la investigación mencionada evaluamos seis potenciales impactos sobre el medio ambiente: el potencial de calentamiento global, el potencial de acidi.cación, el potencial de eutro.zación, el potencial de destrucción de la capa de ozono, el potencial de formación de esmog fotoquímico y toxicidad para los seres humanos. El potencial de calentamiento global conectado con la producción de 1 kg del producto de carne de cerdo es 9,04 kg CO2Eq. El potencial de acidi.cación dentro de la cadena de carne de cerdo es 9,874 x 10-3 kg SO2Eq y el potencial de eutro.zación es 0,0151 kg PO4Eq. Dentro de la cadena de carne de cerdo los que más inuyen sobre el medio ambiente son la producción del pienso y la gestión del estiércol. La inuencia de la planta para el procesamiento de carne se re.ere principalmente a la demanda de agua y energía, y el uso de los sistemas de enfriamiento en la cadena de frío