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Hair as a Biological Trace at the Scene of a Vehicle-Animal Collision
No full textU aspektu sudskog veterinarstva i veterinarske forenzike, ključnu značajku sadrži
upravo dlaka kao najčešći oblik dokaza na mjestu naleta motornog vozila na životinju.
Zahvaljujući iznimnoj otpornosti na vanjske uvjete, dlaka preživljava i u manje
pogodnim okolnostima, omogućavajući tako analizu u svrhu identifikacije pojedine
životinjske jedinke. Strukturno gledano, dlaka se sastoji od medule (srži vlasi), korteksa
(središnjega, nosivog sloja) i kutikule (vanjskog, zaštitnog sloja). Morfološka obilježja
svake od ovih komponenti mogu, ovisno o vrsti, značajno varirati, pa nam mikroskopski
pregled daje vrijedne informacije o redu ili čak porodici kojoj životinja pripada.
Međutim, kada je riječ o blisko srodnim vrstama ili potencijalno hibridnim sojevima,
isključivo morfološka analiza može biti nedostatna. U takvim slučajevima posežemo
za molekularnim metodama (npr. PCR, PCR-RFLP ili sekvenciranjem), koje, unatoč
većim troškovima i tehničkoj složenosti, nude detaljnu genetičku potvrdu identiteta. U
ovoj su studiji opisane i makroskopske i mikroskopske karakteristike dlake, uz poseban
naglasak na sedam europskih sisavaca: divlju svinju (Sus scrofa), jelena običnog
(Cervus elaphus), jelena lopatara (Dama dama), srnu (Capreolus capreolus), lisicu
(Vulpes vulpes), psa (Canis lupus), mačku (Felis silvestris forma catus) te običnog
europskog zeca (Lepus europaeus). Dodatno su predstavljeni sudski slučajevi iz prakse,
gdje ove spoznaje o strukturi i molekularnoj analizi dlake nalaze svoju konkretnu
primjenu. Na taj se način jasno pokazuje kako teorijske informacije iz područja
morfologije dlake i molekularne forenzike mogu biti presudne u rasvjetljavanju nesreća
s divljim i domaćim životinjama, ali i u rješavanju sudskih procesa ili nezakonitih radnji
koje uključuju životinje.Within the context of forensic veterinary medicine and veterinary forensics, hair
emerges as the key form of evidence at the site of a vehicle–animal collision. Due to its
remarkable resilience to environmental factors, hair often survives under less favorable
conditions, thus allowing for an analysis aimed at identifying the individual animal.
Structurally, hair is composed of the medulla (the core), the cortex (the central,
supportive layer), and the cuticle (the outer, protective layer). The morphological
features of each of these components can vary considerably depending on the species,
which is why microscopic examination can yield valuable information about the order
or even the family to which the animal belongs. However, when it comes to closely
related species or potentially hybrid strains, relying solely on morphological analysis
may be insufficient. In such cases, we resort to molecular methods (e.g., PCR, PCRRFLP, or sequencing), which, despite higher costs and technical complexity, offer a
detailed genetic confirmation of identity. This study describes both the macroscopic
and microscopic characteristics of hair, with particular emphasis on seven European
mammals: the wild boar (Sus scrofa), red deer (Cervus elaphus), fallow deer (Dama
dama), roe deer (Capreolus capreolus), fox (Vulpes vulpes), dog (Canis lupus), cat
(Felis silvestris forma catus), and the European hare (Lepus europaeus). In addition,
real-life court cases are presented, illustrating how these insights into hair structure and
molecular analysis are applied in practice. In this way, it becomes evident that
theoretical knowledge from the field of hair morphology and molecular forensics can
be crucial for clarifying accidents involving both wild and domestic animals, as well as
for resolving legal proceedings or unlawful activities related to animals
Influence of rib stiffeners stiffness on the stress distribution in a medium power transformer boiler
No full textS obzirom na nedavni porast cijena materijala na svjetskom tržištu mnoge tvrtke rade na optimiranju svojih dijelova u cilju što većeg smanjenja mase i povećanja financijske isplativosti njihovih proizvoda. Tako i tvrtka Končar-Distributivni i specijalni transformatori pokušava optimizacijom dijelova kotla, pomoću numeričkih analiza, smanjiti masu dijelova transformatora na kojima je optimizacija moguća uz određeni faktor sigurnosti. Jedan od dijelova na kojemu se može provesti optimiranje je ukruta transformatora koja ima zadatak povećati krutost kotla transformatora.
U ovom radu, smanjenje mase ukruta na kotlu transformatora prikazano je na principu orebrene ploče. Numeričkom analizom prikazana su naprezanja i pomaci stranice kotla za stvarnu ukrutu koja je zavarena na stranicama kotla te alternativna rješenja za ukrute koja bi zadovoljila uvjete čvrstoće i krutosti. Mijenjanjem dimenzija i materijala, provedbom analize te približavanjem točni rezultatima primjenom konvergencije rješenja, određena su sva rješenja sa stajališta mase i financija te je odabrano konačno i najbolje rješenje.Given the recent rise in material prices on the world market, many companies are working to optimize their parts in order to maximize weight loss and increase the financial viability of their products. Thus, the company Končar-Distributivni i specijalni transformatori is trying to reduce the mass of transformer parts where optimization is possible with a certain safety factor by optimizing the transformer parts, using numerical analyzes. One of the parts on which optimization can be carried out is the rigidity of the transformer which has the task of increasing the rigidity of the transformer boiler.
In this paper, the reduction of the stiffness mass on the transformer boiler is shown on the principle of a ribbed plate. Numerical analysis shows the stresses and displacements of the boiler side for the actual stiffness welded to the boiler sides and alternative stiffening solutions that would meet the conditions of strength and stiffness. By changing the dimensions and materials, conducting the analysis and approaching the exact results by applying the convergence of solutions, all solutions from the point of view of mass and finance were determined and the final and best solution was chosen
Synthesis and structural characterization of new quinoline and triazole derivatives with potential antitrypanosomal activity
No full textCilj ovog rada je sinteza novih derivata kinolina i triazola i njihovih Re(I) trikarbonilnih kompleksa te sinteza derivata kinolina i heterocikličkih hidrazona. Derivati kinolina i triazola (9a−9c, 10a, 11a−11c) dobiveni su mehanokemijskom sintezom kojom je provedena reakcija cikloadicije azida i alkina katalizirana Cu(I). Spojevi 9a i 10a nadalje su korišteni kao ligandi za kompleksiranje s Re(I) pentakarbonil-kloridom (9aRe, 10aRe). 2-(trifluormetil)kinolin-4-oli dobiveni su Conrad–Limpachovom ciklokondenzacijom te su, kao i 3-nitro-1,2,4-triazol, potom prevedeni u odgovarajuće alkine i azide. Klik reakcija alkina i azida provedena je primjenom azidnih kinolina i N-propargiliranog 1,2,4-triazola te korištenjem O-alkiliranih kinolina i azidnog triazola. Derivati kinolina i hidrazona (15a−15d, 16a−16d) dobiveni su nukleofilnom adicijom hidrazinskih kinolina na karbonilnu skupinu heterocikličkih aldehida, praćenom dehidratiranjem. Strukture spojeva potvrđene su spektroskopijom 1H i 13C NMR, karakteristične apsorpcijske vrpce potvrđene su IR spektroskopijom, a strukture derivata kinolina i hidrazona dodatno su potvrđene visokoučinkovitom spektrometrijom masa. Biološka ispitivanja novosintetiziranih spojeva (9a−9c, 10a, 11a−11c, 9aRe, 10aRe, 15a−15d, 16a−16d) su u tijeku.The aim of this work is the synthesis of novel quinoline and triazole derivatives as well as their Re(I) tricarbonyl complexes. Preparation of quinoline-based hydrazone derivatives was also performed. Quinoline triazole derivatives (9a−9c, 10a, 11a−11c) were synthesized by Cu(I)-catalyzed azide–alkyne cycloaddition using mechanochemistry. Compounds 9a and 10a served as ligands for complexation with Re(I) pentacarbonyl chloride, yielding metal complexes 9aRe and 10aRe. 2-(Trifluoromethyl)quinolin-4-ols were synthesized through Conrad–Limpach cyclocondensation, and together with 3-nitro-1,2,4-triazole, were transformed into corresponding alkynes and azides. Click reactions were performed by reaction of azido-substituted quinolines and N-propargylated 1,2,4-triazole, and O-alkylated quinolines and azido triazoles. Hydrazone derivatives (15a−15d, 16a−16d) were obtained via nucleophilic addition of quinoline hydrazines to the carbonyl group of heterocyclic aldehydes, followed by dehydration. The structures of the synthesized compounds were confirmed by ¹H and ¹³C NMR spectroscopy, characteristic absorption bands were identified by IR spectroscopy and the structures of the quinoline hydrazone derivatives were further confirmed by high resolution mass spectrometry. Biological evaluation of the newly synthesized compounds (9a−9c, 10a, 11a−11c, 9aRe, 10aRe, 15a−15d, 16a−16d) is currently underway
Application of steel electrodes in the treatment of compost wastewater by the combined process of electrocagulation, zeolite and magnet : diploma thesis
No full textU ovom radu je ispitan utjecaj NdFeB magneta na proces elektrokoagulacije u kombinaciji sa zeolitom u cilju pročišćavanja otpadne vode. Korišten je stakleni elektrokemijski reaktor s elektrodama od ugljičnog čelika pri čemu je NdFeB magnet bio smješten ispod reaktora. Ispitivanja su provedena u vremenskom periodu od 10 do 30 minuta, bez i s podešavanjem pH vrijednosti na pH = 3,72, pri čemu su mjereni parametri kao što su promjena pH vrijednosti i temperature otopine s vremenom, promjena mase elektroda, napon i sposobnost taloženja suspenzije. Rezultati su pokazali da postupak elektrokoagulacije s magnetom dovodi do nešto većeg porasta pH otopine i nešto manjeg porasta temperature u usporedbi s elektrokoagulacijskim postupkom. Primijećeno je smanjenje kemijske potrošnje kisika (KPK) za 84.08- 91.00% nakon 30 minuta provedbe eksperimenta, bez vidljivog utjecaja magneta na ove vrijednosti. Nešto veća oštećenja površine elektroda su vidljiva kod upotrebe magneta pri čemu se najveće promjene uočavaju kod mjerenja od 20 minuta. Smanjenje mase anode raste s vremenom provođenja eksperimenta, a uočena je i mala promjena mase katode. Oba hibridna postupka omogućuju 80-100% regeneracije mase zeolita. Manja potrošnja energije (niže vrijednosti napona i snage) su potrebne kod postupaka koji su provedeni korištenjem magneta u odnosu na eksperimente bez magneta. Pozitivan utjecaj magneta na taloženje zamijećen je u eksperimentu s vremenom kontakta od 20 minuta.In this work, the influence of the NdFeB magnet on the electrocoagulation process in combination with zeolite for wastewater treatment is investigated. An electrochemical glass reactor with carbon steel electrodes was used, under which a NdFeB magnet was attached. The tests were carried out over a period of 10 to 30 minutes, without and with the pH adjusted to pH = 3.72, measuring parameters such as the change in pH and temperature of the solution over time, the change in the mass of the electrode, the voltage and the ability to settle the suspension. The results showed that the electrocoagulation method with a magnet led to a slightly higher increase in the pH of the solution and a slightly lower increase in temperature compared to the electrocoagulation method. After 30 minutes of the experiment, a decrease in chemical oxygen demand (COD) of 84.08-91.00% was observed without the magnet having a visible effect on these values. When a magnet is used, slightly greater damage to the electrode surface is visible, with the most significant changes observed in measurements from 20 minutes onwards. The decrease in the anode's mass increases with the experiment's duration, but a small change can also be observed in the mass of the cathode. Both hybrid processes enable 80-100% regeneration of the zeolite. Procedures carried out with a magnet require less energy consumption (lower voltage and power values) than experiments without a magnet. The positive influence of the magnet on the deposition was observed in the experiment with a contact time of 20 minutes
Optimization of the generator frame bracket
No full textHidroenergija je vodeći izvor obnovljive električne energije, a njezin potencijal u današnjem
svijetu je iznimno velik zbog velikih zahtjeva za čistom energijom. Glavni stroj za generiranje
električne energije iz hidroenergije je generator, koji mehaničku energiju dobivenu iz turbine
pretvara u električnu energiju. Pri tom procesu, kućište generatora preuzima velike sile koje se
prenose putem turbine i vratila, što zahtijeva izdržljivost i čvrstoću svih njegovih komponenti.
Jedna od ključnih komponenti koja osigurava pravilan rad generatora i njegovu krutost je štit
generatora koji je sastavni dio kućišta i odgovaran za prijenos aksijalna opterećenja. Ispravno
dimenzioniran i optimiziran štit ključan je za povećanje sigurnosti i vijeka trajanja generatora.
Ovaj rad bavi se optimizacijom konstrukcijskog rješenja štita kućišta generatora za primjenu u
hidroelektranama. Prvi korak je analiza mehaničkih karakteristika plitkog štita, s naglaskom
na njegovu krutost, primjenom metode konačnih elemenata (MKE). Detaljnom analizom
procijenit će se sposobnost štita da prenosi aksijalna opterećenja te osigurava stabilnost
cijelog sustava. Nadalje, potrebno je razmotriti opravdanost primjene dubokog štita u odnosu
na plitki štit. Ove dvije izvedbe razlikuju se po obliku i načinu izrade. Sljedeća faza rada
uključuje simulaciju postupka zavarivanja kako bi se analizirala zaostala naprezanja koja
mogu utjecati na integritet i vijek trajanja štita. Rezultati ove analize omogućit će bolje
razumijevanje ponašanja materijala tijekom zavarivanja te identificirati potencijalne slabe
točke koje bi mogle ugroziti stabilnost konstrukcije. Također, ova simulacija pridonosi
unapređenju procesa izrade štita i smanjenju rizika od pukotina ili deformacija. Na temelju
provedenih analiza, izradit će se optimizirano konstrukcijsko rješenje dubokog štita. U sklopu
optimizacije provest će se numerička analiza čvrstoće i krutosti kako bi se osigurala
odgovarajuća nosivost i pouzdanost štita. Cilj je postići optimalno konstrukcijsko rješenje
koje zadovoljava sve tehničke zahtjeve uz visoku učinkovitost, stabilnost i dugotrajnost
sustava. Na kraju rada, svi mjerljivi parametri bit će uspoređeni kako bi se utvrdila
opravdanost primjene optimiziranog štita. Usporedit će se aksijalna krutost, maksimalna
naprezanja i troškovi izrade kako bi se donio konačni zaključak o isplativosti novog rješenja.Hydropower is the leading source of renewable electricity, and its potential in today's world is
exceptionally high due to the increasing demand for clean energy. The primary machine for
generating electricity from hydropower is the generator, which converts mechanical energy
from the turbine into electrical energy. During this process, the generator housing absorbs
significant forces transmitted through the turbine and shaft, necessitating the durability and
strength of all its components. One of the key components ensuring the proper operation and
rigidity of the generator is the generator shield, which is an integral part of the housing and
responsible for transferring axial loads. A properly dimensioned and optimized shield is
essential for enhancing the safety and lifespan of the machine. This thesis focuses on optimizing
the mechanical design of the housing shield for application in hydropower plants. The first step
involves analyzing the mechanical characteristics of the shallow shield, with an emphasis on its
rigidity, using the Finite Element Method (FEM). A detailed analysis will assess the shield's
ability to transfer axial loads and ensure the system's overall stability.
Furthermore, it is necessary to evaluate the justification for using a deep shield compared to a
shallow shield. These two designs differ in shape and manufacturing methods. The next phase
of the study involves simulating the welding process to analyze residual stresses that may affect
the integrity and lifespan of the shield. The results of this analysis will provide better insight
into the material's behavior during welding and help identify potential weak points that could
compromise structural stability. This simulation also contributes to improving the shield
manufacturing process and reducing the risk of cracks or deformations. Based on the conducted
analyses, an optimized structural solution for the deep shield will be developed. As part of the
optimization, a numerical study of strength and rigidity will be performed to ensure adequate
load-bearing capacity and reliability of the shield. The goal is to achieve an optimal design that
meets all technical requirements while ensuring high efficiency, stability, and durability of the
system. At the end of the thesis, all measurable parameters will be compared to determine the
justification for implementing the optimized shield. Axial rigidity, maximum stresses, and
manufacturing costs will be evaluated to draw a conclusion regarding the cost-effectiveness of
the new solution
Process improvement in wiring assembly
No full textKonstantnim unaprjeđenjima automobilske industrije, dodavanjem brojnih senzora, digitalnih zaslona u kokpit automobila i svjetskim okretom prema električnim automobilima kao načinu borbe s globalnim zatopljenjem, automobilska ožičenja postaju ključna komponenta proizvodnje automobila. Automobilska ožičenja su nezaobilazne strukture potrebne za povezivanje svih komponenata unutar automobila. Proces proizvodnje automobilskog ožičenja i kako ga unaprijediti postaje novi izazov za procesne inženjere u proizvodnji. Glavni cilj ovog rada je opisati procese u montaži automobilskog ožičenja, pokazati kako se koriste Lean alati i kako oni unaprjeđuju procese. Osim toga, definirat će se nadolazeći trendovi s naglaskom na Industriju 4.0. Sva unaprjeđenja procesa su prikazana na stvarnom primjeru u Rimac Automobili d.o.o. u prijelazu iz pojedinačne na serijsku proizvodnju.With the automotive industry constantly improving the user experience by adding numerous sensors, digital displays in car cockpits and the global turn to the electrical automobiles to combat climate changes, wiring harnesses become key components in car production. Wiring harnesses are unavoidable structures necessary for connecting all components within the car. Wiring harness assembly process and how to improve it becomes the new challenge for process manufacturing engineers. The main goal of this bachelor’s thesis is to describe processes in wiring harnesses assembly, show how lean tools are used and do they improve the process, define key performance indicators and list upcoming trends in harness assembly with an emphasis on Industry 4.0. All process improvements are shown on the real example in Rimac Automobili d.o.o. in transition from prototype to serial car production
Synthesis and characterisation of a cellulose derivative and dibutyl maleate graft copolymer
No full textCeluloza je zastupljen polisaharid u prirodnom svijetu. Nalazi se u staničnim stijenkama biljaka, a može se dobiti i iz drugih izvora poput bakterija. Iz tog je razloga ona, kao sirovina, vrlo pristupačna. Zbog svoje biokompatibilnosti vrlo je zastupljena u farmaceutskoj industriji za svrhe poput dostave lijekova unutar organizma. Zbog jakih intermolekularnih interakcija, celuloza nije topiva u većini otapala, što u farmaceutskoj industriji nije poželjno. Iz tog razloga se često koriste njeni derivati gdje su hidroksilne skupine zamijenjene drugim funkcionalnim skupinama. U ovom se radu provodila cijepljena kopolimerizacija natrij karboksimetil celuloze dibutil maleatom uz inicijator cerij (IV) amonijev nitrat te cijepljena kopolimerizacija (hidroksipropil)metil celuloze s kopolimerom maleinskog anhidrida i dibutil maleata uz inicijator azobisizobutironitril. Svrha ovog rada bila je sinteza cijepljenih kopolimera radi njihove potencijalne primjene kao stabilizatorima aktivnih farmaceutskih sastojaka. Dobiveni produkti su karakterizirani diferencijalnom pretražnom kalorimetrijom, termogravimetrijskom analizom i infracrvenom spektroskopijom s Fourierovim transformacijama.
Uspješno je sintetiziran kopolimer natrij karboksimetil celuloza-graft-poli(dibutil maleat) (NaCMC-g-DiBuMal), ali uz nisko iskorištenje reakcije od 3%.Cellulose is a abundant polysaccharide nature. It is found in the cell walls of plants and can also be obtained from other sources like bacteria, making it an easily accessible raw material. Due to its biocompatibility, cellulose is widely used in the pharmaceutical industry for applications such as drug delivery. However, because of its strong intermolecular interactions, cellulose is not soluble in most solvents, which is undesirable in pharmaceutical applications. To address this issue, derivatives of cellulose are often used, where the hydroxyl groups are replaced with other functional groups. In this study, graft copolymerization of sodium carboxymethyl cellulose (NaCMC) with dibutyl maleate was conducted using cerium (IV) ammonium nitrate as the initiator. Additionally, graft copolymerization of (hydroxypropyl)methyl cellulose with a copolymer of maleic anhydride and dibutyl maleate was carried out using azobisisobutyronitrile as the initiator. The purpose of this study was to synthesize graft copolymers for their potential application as stabilizers of active pharmaceutical ingredients. The products obtained were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and
Fourier-transform infrared spectroscopy (FTIR). The copolymer sodium carboxymethyl cellulose-graft-poly(dibutyl maleate) (NaCMC-g-DiBuMal) was successfully synthesized, butSwith a reaction yield of 3% while the syntesis using HPMC yielded no result
Increasing the efficiency of machines in the process industry using Lean and Industry 4.0
No full textU ovom su radu obrađene moderne metodologije upravljanja proizvodnjom: Lean menadžment i Industrija 4.0, te je obrađen realni primjer iz proizvodnje s primjenom odabranih metoda. Uvodni dio rada sadržava povijest, odnosno razvoj Lean menadžmenta i Industrije 4.0 te osnovne principe i gubitke definirane Lean-om. Lean menadžment je filozofija upravljanja procesima (proizvodnim, ali i drugim) te obuhvaća širok spektar metodologija koje su se razvile kroz dugi niz godina. Također obrađene su najpoznatije i najčešće korištene metode poput SMED-a, 5S-a, VSM-a, Kaizen-a, TPM-a. Svaki Lean alat služi drugoj svrsi i može se koristiti u drugoj situaciji. Pa se tako 5S najčešće koristi za organizaciju radnog mjesta kako bi sav alat bio lako dostupan. SMED se primjenjuje za ubrzavanje izmjene alata dok proizvodnja stoji. VSM služi kako bi se grafički prikazao proces sa svim svojim stavkama i potprocesima što olakšava uočavanje gubitaka. Kaizen pristup organizira sistematičan način rješavana problema u timovima. U drugom dijelu rada obrađene su tehnologije koje pripadaju posljednjoj industrijskoj revoluciji zvanoj Industrija 4.0. Industrija 4.0 zbirni je naziv za najmodernije tehnologije koje se razvijaju i implementiraju u industriju (i drugdje). Takvih tehnologija je mnogo te se one kontinuirano unaprjeđuju. Obrađene su i najčešće i najpoznatije tehnologije poput Internet of Things, aditivne proizvodnje, izmijenjene stvarnosti. Internet of Things ponajprije služi povezivanju strojeva i omogućavanu njihove međusobne komunikacije. Aditivna proizvodnja naziva se još i 3D printanje te se u industriji koristi za brzu izradu prototipova. Izmijenjena stvarnost omogućava prikaz željenih elemenata u stvarnom vremenu dodanih u stvarnost kroz posebne naočale ili na druge načine. U posljednjem dijelu rada opisano je jedno proizvodno poduzeće te procesi koji se odvijaju unutar istog. Odabran je proces u poduzeću na kojem će biti prikazane odabrane metode Lean menadžmenta i tehnologije koje spadaju u početke procesa transformacije poduzeća u Industriju 4.0.This paper deals with modern production management methodologies: Lean management and Industry 4.0, as well as a real-life example from production with the application of selected methods. The introductory part of the paper contains the history, that is, the development of Lean management and Industry 4.0, as well as the basic principles and waste defined by Lean. Lean management is a philosophy of process management (production, but also other) and includes a wide range of methodologies that have been developed over many years. This work covers the well-known and most frequently used methods such as SMED, 5S, VSM, Kaizen, and TPM. Each Lean tool serves a different purpose and can be used in different situations. So 5S is most often used to organize the workplace so that all tools are easily accessible. SMED is applied to speed up tool changes while production is at a standstill. VSM graphically displays the process with all its items and sub-processes, which makes it easier to spot losses. The Kaizen approach organizes a systematic way of solving problems in teams. In the second part of the work, the technologies belonging to the last industrial revolution called Industry 4.0 are discussed. Industry 4.0 is a collective name for the most modern technologies that are developed and implemented in the industry (and elsewhere). There are many such technologies and they are continuously being improved. The paper deals with the most common and well-known technologies such as the Internet of Things, additive manufacturing, and altered reality. The Internet of Things primarily connects machines and enables their mutual communication. Additive manufacturing is also called 3D printing and is used in industry for rapid prototyping. Altered reality allows the display of desired elements in real-time added to reality through special glasses or in other ways. In the last part of the paper, one production company and the processes that take place within it will be described. A process has been selected in the company where selected methods of Lean management and technologies that belong to the beginnings of the process of transforming the company into Industry 4.0 will be presented
Stress analysis of the transformer’s anchoring system due to earthquake
No full textTema ovog završnog rada je analiza naprezanja sidrenog sustava transformatora uslijed potresa. Cilj rada je provesti računalnu analizu naprezanja dna transformatora uslijed djelovanja potresnog opterećenja kako bi se provjerio jedan od sustava sidrenja transformatora unutar tvrtke Končar D&ST. Analiza je provedena uz pomoć dinamičkih modula programskog paketa Abaqus. Rad se sastoji od 6 poglavlja koja zaokružuju cijelu tematiku vezanu uz naziv rada. U prvom poglavlju je napravljen pregled tematike energetskog sustava kako bi se shvatila uloga transformatora u istom. U drugom poglavlju je transformator podijeljen na aktivni te na pasivni dio kako bi se objasnila zadaća pojedinih dijelova transformatora. Treće poglavlje je svojevrsni preglednik najvažnijih pojmova vezanih za potrese. Problematika četvrtog poglavlja su vrste analiza potresnih opterećenja, kao podsjetnik na važnost i prednost numeričkih analiza unutar programskih paketa koji olakšavaju svakodnevnu inženjersku praksu. Posljednja dva poglavlja su vezana uz numeričku analizu te zaključke koji su izvedeni na temelju dobivenih rezultataThe topic of this final thesis is stress analysis of the transformer’s anchoring system due to earthquake. The aim of this paper is computer analysis of the Končar D&ST transformer’s tank bottom, due to earthquake load. The analysis was provided by dynamic modules in Abaqus software package. The paper is composed of six chapters, which round off the mentioned topic. In the first chapter, review of the whole energetic system was done, as well as clearing up the function of the transformer. In the second chapter transformer is divided on active and passive parts, which are all explained in details. In the third chapter, most important concepts of earthquake are described. Different types of earthquake load analyses are presented in chapter four, pointing out importance and benefits of numerical analysis, incorporated in software packages, which make engineer’s working days easier. The last two chapters are dedicated to the numerical analysis and conclusions, based on acquired results
Spectroscopic determination of glucosinolates in plants Sinapis alba and Lepidium draba : diploma thesis
No full textU ovom radu UHPLC-DAD-MS/MS analizom odreĎen je glukozinolatni profil različitih biljnih dijelova biljke Lepidium draba i nepoznatog biljnog uzorka te glukozinolatni profil sjemenki biljke Sinapis alba. Glukozinolati su iz uzoraka izolirani u desulfatiranome obliku modificiranom metodom ISO 9167-1. Dobiveni glukozinolatni profil biljke Lepidium draba usporeĎen je s glukozinolatnim profilom nepoznate biljne vrste kako bi se odredile kemotaksonomske značajke nepoznatog biljnog uzorka. U oba uzorka, najveći udio glukozinolata je pronaĎen u listu, a najmanji u stabljici. Pri tome, najzastupljeniji spoj u listu oba uzorka je glukorafanin (41,49 ± 4,05 μmol/g suhog biljnog materijala biljke Lepidium draba te 40,40 ± 3,62 μmol/g suhog biljnog materijala nepoznatog uzorka), a u cvatu pak glukosinalbin (32,03 ± 5,43 μmol/g u biljci Lepidium draba te 34,73 ± 0,76 μmol/g u nepoznatom uzorku). Najzastupljeniji glukozinolati u oba uzorka potječu od metionina. Na temelju znatne sličnosti glukozinolatnih profila uzoraka te UV i MS2 spektara, zaključeno je da nepoznatni uzorak vjerojatno pripada vrsti Lepidium draba. Obzirom da je glukozinolatni profil sjemenki biljke Sinapis alba bio uvelike jednostavniji od gore navedenih uzoraka, taj uzorak je posluţio za potvrdu strukture najzastupljenijeg spoja sjemenki - desulfoglukosinalbina. Struktura je potvrĎena NMR tehnikom te je utvrĎena β konfiguracija anomernog ugljikovog atoma glukozne jedinice glukosinalbina.In this paper, UHPLC-DAD-MS/MS analysis was used for determination of the glucosinolate profile of various plant parts of Lepidium draba and an unknown plant sample, as well as the glucosinolate profile of Sinapis alba seeds. Glucosinolates were isolated from the samples in their desulfated form using a modified ISO 9167-1 method. The obtained glucosinolate profile of Lepidium draba was compared with the glucosinolate profile of the unknown plant species in order to determine chemotaxonomic characteristics of the unknown plant sample. In both samples, the highest glucosinolate content was found in the leaves, while the lowest content was found in the stem. The most abundant compound in the leaves of both samples was glucoraphanin (41.49 ± 4.05 μmol/g dry plant material of Lepidium draba and 40.40 ± 3.62 μmol/g dry plant material of the unknown sample) and glucosinalbin in the inflorescence (32.03 ± 5.43 μmol/g in Lepidium draba and 34.73 ± 0.76 μmol/g in the unknown sample). The most abundant glucosinolates in both samples are derived from methionine. Based on the significant similarity in the glucosinolate profiles and UV and MS2 spectra of the samples, it was concluded that the unknown sample likely belongs to the Lepidium draba species. Since the glucosinolate profile of Sinapis alba seeds was much simpler than that of the above-mentioned samples, this sample was used for confirmation of the structure of the most abundant compound in the seeds - desulfoglucosinalbin. The structure was confirmed using NMR techniques, and the β configuration of the anomeric carbon atom of the glucose unit of glucosinalbin was determined