<p>Doktorska disertacija obuhvata vi&scaron;egodi&scaron;nja istraživanja koja se odnose na razvoj u tehnolo&scaron;kom unapređenju održavanja jednodelnih točkova železničkih vučenih vozila, uz primenu savremenih metoda i postupka dijagnostikovanja u cilju postizanja zadovoljavajućeg nivoa pouzdanosti pri eksploataciji.<br />Sveobuhvatnim istraživanjem pokazano je da uvođenjem ovog novog tehničko-tehnolo&scaron;kog postupka održavanja venca monoblok točka kvaliteta ER7, čini veliki značaj u tehnolo&scaron;kom unapređenju održavanja vitalnog dela &scaron;inskih vozila-točka, u sopstvenim radioničkim kapacitetima na&scaron;ih železničkih uprava. Istraživanjem je, takođe, potvrđeno da implementacija ovog, sasvim novog tehničko-tehnolo&scaron;kog postupka održavanja venca monoblok točka, je primenljiv i izvodljiv tehničko-tehnički postupak, u postojećim radioničkim kapacitetima koje se bave problematikom održavanja železničkih vozila bez znatnih investicionih ulaganja.<br />Istraživanja su se odvijala po fazama. Prvo su detaljno implementirana teoretska istraživačka dostignuća, zasnovana na izučavanju i primjeni savremenih tehnika i tehnologija na održavanju vitalnih elementa železničkih tehničkih sistema. Implementacija ovog teorijskog istraživanja, realno je produkovalo u zdrav i sveobuhvatan naučno-istraživački temelj, koji je omogućio opravdan pristup eksperimentalnom, a potom i eksploatcaionom istraživanju. Takvim sveobuhvatnim naučno-istraživačkim procesom, rezultiralo je u zadovoljavajuća naučno-istraživačka saznanja, koja će, sigurni smo, stvoriti zdravu podlogu za naučno razmatranje, a potom, i pristup, ka praktičnoj primeni od strane železničkih uprava na&scaron;ih zemalja.<br />Ceo proces istraživanja predmeta disertacije, baziran je na najnovijim dostignućima naučnog saznanja iz oblasti ma&scaron;instva koje izučavaju: tehnologiju obrade metala, tehnologiju proizvodnje čelika, mehanike metala, otpornosti materijala, potom metalurgije zavarivanja, fizike, hemije itd.<br />Eksperimentalna i eksploataciona istraživanja, pratile su savremene dijagnostičke metode i postupci, meritorne za dono&scaron;enje naučnih odluka i dokaza o nivou kvaliteta i pouzdanosti. Pokazano je da pored metoda mehnike loma metala i standardnih metalru&scaron;kih metoda ispitivanja, uvođenjem savremenih ultrazvučnih dijagnostičkih tehnika i tehnologija, u proces dijagnostikovanja vitalniog dela žlezničkih vozila, to jest monoblok točka, uveliko obezbeđuju visok stepen pouzdanosti, dajući značajan doprinos ovom istrživačkom radu, za potvrdu izvodljivosti tehničko-tehnolo&scaron;kog procesa.<br />Tehničko-tehnolo&scaron;kog procesa obnavljanja venaca monoblok točka kvaliteta ER7, navarivanjem, a izloženi mehničkim procesom tro&scaron;enja i kombinovanim statičkim i dinamičkim opterećenjima, pri eksploatciji, ne može se zamisliti bez primene pouzdanih tehnika dijagnostikovanja. Na taj način, kroz vi&scaron;e tehničkih faza obimnih istraživanja, potvrđena je i dokazana neophodnost primene dijagnostičkih metoda bez razaranja zasnovanih na polju ultrazvučne defektoskopije, kako bi se potvrdio i uvećao uticaj na pouzdanost tehničkog sistema-železničko vozilo.</p> / <p>Doctoral dissertation includes several years of research concerning the development of technological<br />6<br />improvement in the maintenance of oneparted railway wheels towed vehicle, with modern methods of diagnosis and procedure in order to achieve satisfactory levels of reliability in operation. Comprehensive research has shown that the introduction of this new technological process of maintaining of the wreath of monoblock wheels, quality ER7, makes a great technological importance in improving the maintenance of vital rail vehicle-point in our own workshop facilities of railway direction. The study also confirmed that, the implementation of this, an entirely new technological maintenance procedures wreath monoblock wheel, is applicable and feasible technical and technical process for the existing workshop facilities to deal with the problem of maintenance of railway vehicles without significant investment. Surveys were conducted in stages. First in detail are implemented the theoretical research achievements, based on the study and application of modern techniques and technologies, made to maintain the vital elements of railway technical systems. Implementation of this theoretical study is produced by the realistic sound and comprehensive scientific foundation, which allowed reasonable access to experimental, and also exploitation research. This comprehensive scientific research process, resulted a satisfactory scientific research findings, which for sure will create a sound basis for scientific discussion and also access to practical use by the railway companies of our country. The whole process of dissertation research subjects is based on the latest achievements of scientific knowledge in mechanical engineering studies such as: the technology of metal processing, steel production technology, metal mechanics, strength of materials, welding metallurgy, physics, chemistry, etc.. Experimental research and exploitation, were accompanied by modern diagnostic methods and procedures, merit-making for the adoption of scientific decisions and evidence at the level of quality and reliability. It is shown that besides the methods of fracture of metals and mechanics metallurgy standard test methods, the introduction of modern ultrasonic diagnostic techniques and technologies in the process of diagnosing vital railway vehicle, as a monoblock points, largely provides a high degree of reliability by providing a significant contribution to this research for confirming technological feasibility of the process. Technological process of wreath restoring of monoblock wheels, quality ER7, which are subjected to the mechanical process of wear and combinated static and dynamic loads, in the process od exploitation, it can not be imagined without the use of reliable diagnostic techniques. Thus, through the more technical phases of extensive research, has been confirmed and proved the necessity of applying nondestructive diagnostic method based on the field of ultrasound defectoscopy, with the purpose of confirmation and increasing of impact on the reliability of technical systems and rail car.&nbsp;</p>

<p>Dat je pregled i analiza performansi lakih vojnih terenskih točka&scaron;kih vozila (LVTTV), lakih komercijalnih terenskih točka&scaron;kih vozila (LKTTV) u Pik-ap verziji i postojećih sistema naoružanja pogodnih za primenu na LKTTV Pik-ap verzija.<br />Posebno je razmotrena problematika elastično-prigu&scaron;nog oslanjanja naoružanja pri njegovom jediničnom dejstvu.<br />Definisana je metodologija i projektovana je i realizovana oprema za simulaciju impulsne sile u cilju statičkih i dinamičkih ispitivanja sistema vozilo-platforma-naoružanje u laboratorijskim uslovima.<br />Prikazan je postupak ispitivanja pri statičkom opterećenju sistema i dinamičkih ispitivanja sistema vozilo-platforma-naoružanje u uslovima kontinuirane impulsne sile u cilju odredjivanja pomeranja &scaron;asije u zonama točkova i napona u &scaron;asiji vozila i osloncima platforme za prihvat naoružanja.<br />Postavljen je matematički model sistema vozilo-platforma-naoružanje i data teorijska pomeranja &scaron;asije vozila u zonama točkova pri jediničnoj impulsnoj sili odnosno impulsu.</p> / <p>The review and analysis of the performances of military ground wheeled vehicles (LVTTV), light commercial wheeled ground vehicles (LKTTV) of Pick-up version and current systems of armament convenient for the application on LKTTV Pick-up versions, were given.<br />The issues of elastic-absorbtion suspension of armament during its single shooting function was analised in detail.<br />The methodology was defined, the equipment for the simulation of impulse force was designed and realised with purpose of static and dynamic tests of the vehicle-platform-armament system in the laboratory conditions.<br />The test procedure of static and dynamic loads of system vehicle-platform-armament in conditions of continual impulse force was presented. The aim of these tests was the determination of motion of vehicle chassis in the stress of vehicle chassis and platform supports for the armament.<br />The mathematical model of vehicle-platform-armamaent system was defined and theoretical motions of vehicle chassis in the wheels zones under the single impulse force, were given.</p>

<p>U radu je ostvarena totalna sinteza novih acikličnih&nbsp;tiazolnih C-nukleozide sa dvostrukom &nbsp;vezom i&nbsp;2&prime;,3&prime;-dideoksi funkcijom u &scaron;ećernoj komponenti.&nbsp;Ostvarena vi&scaron;efazna sinteza &nbsp;pomenutih acikličnih&nbsp;analoga tiazofurina zasnovana je na D-arabinozi&nbsp;kao hiralnom prekursoru. Ispitana je in vitro&nbsp;citotoksična&nbsp;aktivnost&nbsp;novosintetizovanih&nbsp;nukleozida prema ćelijskim linijama K562, HL-60,&nbsp;HT-29, MCF-7, MDA-MB-231, HeLa, Raji, PC3,&nbsp;Jurkat, Hs 294T i MRC-5, kao i provera ćelijskih&nbsp;mehanizama koji su u osnovi &nbsp;uočenog&nbsp;citotoksičnog potencijala novosintetisanih analoga&nbsp;u odnosu na tiazofurin kao referentno jedinjenje.</p> / <p>A total synthesis of new acyclic thiazole C-nucleozides&nbsp;bearing a double bond or 2&prime;,3&prime;-dideoxy functionality in&nbsp;the sugar moiety was achieved in this work. The multi-step synthesis of the mentioned thiazofurin analogues is&nbsp;based on&nbsp; D-arabinose as a chiral precursor. In vitro&nbsp;cytotoxic activity of newly synthesized compounds was&nbsp;evaluated against the following cell lines: K562, HL-60,&nbsp;HT-29, MCF-7, MDA-MB-231, HeLa, Raji, PC3, Jurkat,&nbsp;Hs 294T and MRC-5. A study of cell mechanisms&nbsp;underlaying the significant cytotoxic potential of these&nbsp;molecules was caried out and the results were compared&nbsp;to thiazofurin that servad as a referent compound in all&nbsp;biological testings.</p>

<p>Predviđena istraživanja u ovoj doktorskoj disertaciji su usmerena u pravcu&nbsp;<br />modifikacije klasičnih metoda i postupaka za transformaciju karboksilne grupe&nbsp;<br />prirodnih i sintetičkih karboksilnih kiselina. Modifikacije su rađene novim,&nbsp;<br />savremenim, ekonomski i ekolo&scaron;ki opravdanim metodama rada u&nbsp;<br />mikrotalasnom reaktoru. Modifikovanim sintetskim postupcima u&nbsp;<br />mikrotalasnom reaktoru urađena je sinteza amida, hidroksamskih&nbsp; derivata,&nbsp;<br />kao i redukcija individualnih naftnih kiselina i&nbsp; sme&scaron;e&nbsp; prirodnih naftnih kiselina&nbsp;<br />&bdquo;Velebit&ldquo; do alkohola. Prirodne naftne kiseline kori&scaron;ćene u ovom radu su prvo&nbsp;<br />izolovane iz gasne frakcije (interval destilacije 168-290 &deg;C) vojvođanske nafte&nbsp;<br />&bdquo;Velebit&ldquo; a potom preči&scaron;ćene i razdvojene na uže frakcije na osnovu različite&nbsp;<br />kiselosti. Nakon toga, izvr&scaron;ena je njihova karakterizacija GC-MS-EI analizom&nbsp;<br />(čime je potvrđeno da dolazi do strukturne diferencijacije kiselina). U radu je&nbsp;<br />takođe ispitana biolo&scaron;ka aktivnost sintetizovanih derivata. Proučavan je uticaj&nbsp;<br />prirodnih naftnih kiselina &bdquo;Velebit&ldquo; i njenih derivata na rast&nbsp; pet sojeva&nbsp;<br />Pseudomonas sp., kao i uticaj odabranih sintetisanih jedinjenja na proliferaciju&nbsp;<br />četiri ćelijske linije humanih tumora pri čemu je kao kontrola služila jedna&nbsp;<br />zdrava humana ćelijska linija.</p> / <p>The investigation of this doctoral dissertation is directed toward the modification of the &nbsp;transformation of the carboxylic group of natural and synthetic carboxylic acids. The dissertation takes into consideration the classical methods and procedures of the reaction and modifies them using microwave reactor. The synthesis of amides, hydroxamic derivatives, as well as the reduction&nbsp; of individual petroleum acids and acid mixtures of natural oil &quot;Velebit&quot; to alcohol were achieved&nbsp; by the modifications made to the synthetic methods in the microwave reactor. The natural oil acids used within this study were first isolated from the gas fraction (distillation interval 168-290 &deg;C) of the Vojvodina&#39;s crude oil &quot;Velebit&quot;, and then purified and separated by the narrow fractions under the different acidity. After that, their characterisation was made by the GC-MS-EI analysis which confirmed that the structural differentiation of&nbsp;&nbsp; acids had been achieved. Also, the biological activity of the synthesized derivatives are analysed. The impact of natural petroleum acids &quot;Velebit&quot; and its derivatives on the growth of five strains of&nbsp; Pseudomonas&nbsp; sp. was studied, as well as the impact of selected synthesized compounds on the proliferation of four human tumor cell lines wherein one healthy human cell lines used as the control.</p>