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SUPERCONDUCTIVITY AND MAGNETIC LEVITATION
No full textU prvom dijelu završnog rada objasnjeni su pojmovi supravodljivosti, Meissnerov efekta, BCS teorije, kao i Cooperovi parovi, Londonove jednadžbe, te povijest magnetske levitacije i ona sama. U drugom dijelu objašnjavaju se primjene supravodljivosti, kao i magnetske levitcije u stvarnom životu, susretanje sa odrađenim eksperimentima te objašnjenje Magleovog vlakaThe first part of the Thesis explains the concepts of superconductivity, Meissner effects, BCS theories, as well as Cooper pairs, London equations, and the history of magnetic levitation. The second part of the Thesis explains applications of superconductivity, as well as magnetic levitation in real life, encounters with experiments and the explanation of the
Maglev train
USE OF ERICA SOFTWARE FOR RADIOLOGICAL RISK ASSESSMENT FOR NON-HUMAN BIOTA
No full textAlat ERICA softverski je program koji vodi korisnika kroz proces procjene, vodi
evidenciju i izvodi potrebne izračune za procjenu ukupne brzine apsorbirane doze za odabrane
referentne organizme. Element ocjenjivanja integriranog pristupa ERICA organiziran je u trima
razinama. U ovom diplomskom radu procjenjivali smo radiološki rizik za neljudsku biotu na 8
lokacija Brodsko-posavske županije. Na razini 1 iz izbornika s popisom radionuklida
odaberemo radionuklide: _{}^{137}\textrm{Cs}, _{}^{232}\textrm{Th}, _{}^{238}\textrm{U},
, _{}^226}\textrm{Ra},_{}^{210}\textrm{Pb}, _{}^{235}\textrm{U} čije su vrijednosti koncentracija prethodno izmjerene. Alat uspoređuje upisane koncentracije u tlu s najrestriktivnijim EMCL-om za svaki radionuklid i određuje kvocijent rizika (RQ). Pošto je
jedan RQ > 1, prešli smo na strožu provjeru u razinu 2. Na razini 2 odabrali smo sve referentne organizme na kopnu i faktor nesigurnosti UF=3. ERICA zatim računa transfer faktore radionuklida u svakom organizmu i procjenjuje koncentracije aktivnosti pojedinih radionuklida u svakom organizmu. Razina 2 ispisala je očekivane i konzervativne RQ-ove te ukupne težinske
brzine doza. Za mahovine i lišajeve je očekivani RQ 1. Zbog toga se moralo dodatno istražiti o radiološkim učincima na njih.The ERICA tool is a software program that guides the user through the assessment
process, keeps records and performs the necessary calculations to estimate the total absorbed
dose rate for selected reference organisms. The evaluation element of the ERICA integrated
approach is organized in three levels. In this thesis, we assessed the radiological risk for nonhuman biota at 8 locations in the Brod-Posavina County. At level 1, from the menu with the list
of radionuclides, select the radionuclides: _{}^{137}\textrm{Cs}, _{}^{232}\textrm{Th}, _{}^{238}\textrm{U},
, _{}^226}\textrm{Ra},_{}^{210}\textrm{Pb}, _{ }^{235}\textrm{U} whose concentration values were previously measured. The tool compares recorded soil concentrations with the most restrictive EMCL for each radionuclide and determines a risk
quotient (RQ). Since one RQ>1, we moved to a stricter check in level 2. At level 2, we selected all reference organisms on land and the uncertainty factor UF=3. ERICA then calculates the transfer factors of radionuclides in each organism and estimates the activity concentrations of individual radionuclides in each organism. Level 2 printed expected and conservative RQ s and total weighted dose rates. For mosses and lichens is the expected RQ<1, and the conservative
RQ>1. That is why additional research had to be done on the radiological effects on them
DEVELOPMENT OF INTERACTIVE SIMULATIONS IN BASIC PHYSICS - DETERMINATION OF THE RATIO Cp/Cv
No full textGlavni cilj ovog završnog rada je napraviti simulaciju laboratorijske vježbe određivanja adijabatske konstante. Aplikacija omogućava jednostavno izvođenje pokusa, automatski izračun ključnih vrijednosti kao što su srednja vrijednost, pogreška mjerenja i omjer
specifičnih toplinskih kapaciteta. Time se učenicima olakšava razumijevanje složenih fizikalnih principa, potiče njihova motivacija i povećava sigurnost u radu s eksperimentalnom aparaturom.The main goal of this thesis is to create a simulation of the laboratory exercise for determining the adiabatic constant. The application simplifies the execution of experiments and automatically calculates key values such as the mean value, measurement error, and the ratio of specific heat capacities. By doing so, it facilitates students' understanding of complex
physical principles, enhances their motivation, and increases their confidence in working with experimental equipment
Determination of Planck´s constant using the photoelectric effect
No full textPojavu fotoelektričnog učinka prvi je primijetio njemački fizičar Heinrich Hertz 1887. godine, a objasnio Albert Einstein tek 1905. godine uvođenjem teorije fotona u kojoj opisuje foton kao najmanju nedjeljivu količinu svjetlosti čija je energija jednaka umnošku frekvencije i Planckove konstante koju je Max Planck predložio prilikom opisivanja zračenja crnog tijela. Ruski znanstvenik i izumitelj, Oleg Losev u svojim radovima iznosi tvrdnju da prilikom emisije svjetlosti svjetleće diode dolazi do inverznog fotoelektričnog efekta. Kada je LED dioda propusno polarizirana, elektroni iz n-tipa rekombiniraju sa šupljinama iz p-tipa materijala pri čemu zbog razlike u njihovim energijama dolazi do emisije svjetlosti. Određivanjem napona koljena svjetleće diode i frekvencije emitirane svjetlosti, odnosno valne duljine svjetlosti moguće je odrediti vrijednost Planckove konstante.The occurrence of photoelectric effect was first noticed by German physicist Heinrich Hertz in 1887 and explained by Albert Einstein in 1905 in his photon theory in which a photon is described as quantum whose energy is equal to the product of frequency and the Planck constant proposed by Max Planck which he used for describing black-body radiation. Russian scientist and inventor, Oleg Losev in his publications speculates that an inverse photoelectric effect occurs during the emission of light from a light-emitting diode. When the LED is forward biased, electrons from the n-type recombine with holes from the p-type material and due to the difference in their energies light is emitted. By determining the knee voltage of the lightemitting diode and the frequency of the emitted light, i.e. the wavelength of the light, it is possible to determine the value of Planck's constant
Monte Carlo - integration
No full textMonte Carlo integracija je jedna od najkorisnijih metoda za rješavanje složenih integrala u više dimenzija. Pripada numeričkim metoda rješavanja integrala, a osnova su joj slučajno generirane točke u n-dimenzijskom prostoru koje se nalaze ili unutar ili izvan neke krivulje čiji volumen ili površinu koju zatvara želimo izračunati. Sigurno se pitate jesu li ti brojevi savršeno slučajni
ili koje su još metode numeričke integracije? Na sve to, uz nekoliko primjera ćemo odgovoriti u narednim poglavljima.Monte Carlo integration is one of the most useful methods for solving complex integrals in multiple dimensions. It belongs to numerical methods of solving integrals, and its basis is randomly generated points in n-dimensional space that are located either inside or outside a curve, whose volume or area that curve encloses we want to calculate. You must be wondering
if these numbers are perfectly random or what other methods of numerical integration are there? We will answer all this, with a few examples in the following chapters
APPLICATION OF RADIOACTIVITY - LEVEL BETA GAUGE
No full textU diplomskom radu ukratko je opisan povijesni pregled radioaktivnosti, vrste zračenja, interakcija zračenja i materije te zakon radioaktivnog raspada. Prikazane su sheme radioaktivnog raspada zatvorenih ionizirajućih izvora korištenih prilikom izvođenja pokusa u okviru ovog diplomskog rada i opisani su načini detekcije ionizirajućeg zračenja, posebno Geiger-Müllerovim
brojačem. Opisana je primjena radioaktivnosti u industriji jer se navedeni modeli tamo najčešće koriste. U eksperimentalnom dijelu rada izvedeni su pokusi s potpuno funkcionalnim modelima razinomjera sa zatvorenim radioaktivnim izvorom (gdje je određena razina ispune neprozirnog spremnika olovnom sačmom) i debljinomjera (gdje je određena debljina papira), na temelju kojih
je zaključeno kako su ove metode pogodne za primjenu te imaju prednost kod nekih proizvodnih procesa.In this master thesis briefly described are the historical overview of radioactivity, types of radiation, interactions between radiation and matter and the law of radioactive decay. The decay schemes of closed radioactive sources which were used in experimental part of the thesis are presented and methods of detecting ionizing radiation are described, especially with the GeigerMüller counter. The application of radioactivity in industry are described because the mentioned models are most often used there. In the experimental part of the work, experiments were performed with fully functional models of a level gauge with a closed radioactive source (where the filling level of an opaque tank with lead shot was determined) and a thickness gauge (where the thickness of the paper was determined), based on which it was concluded that these methods are suitable for application and have an advantage in some production processes
GAMIFICATION OF THE NUCLEAR FUSION PROCESS
No full textNuklearna fuzija trenutno je najefikasniji proces dobivanja energije, ali ljudima trenutno najmanje dostupan. Razumijevanjem procesa fuzije pomaže razumijevanju života zvijezda, njihovoj prošlosti, a tako i budućnosti, koja može poboljšati razumijevanje energije u svakom aspektu znanost. Interaktivnim sadržajem o procesu fuzije možemo razumjet sam proces na osnovnoj bazi.Nuclear fusion is currently the most efficient process of obtaining energy, but it is currently the least accessible to people. Understanding of the process of fusion helps to understand the life of stars, their past, and thus their future,
which can improve the understanding of energy in every aspect of science. With interactive content simulating the fusion process, we can understand the process itself effortlessl
VIRTUAL LABORATORY FOR FUNDAMENTALS OF PHYSICS III and IV Simulations of experiments in the field of optics
No full textU ovom diplomskom radu ukratko su opisane zakonitosti geometrijske i fizikalne optike, pokusi predviđeni za izvedbu na nastavi te simulacije četiri odabrana pokusa iz tih područja. Odabrani pokusi su: određivanje indeksa loma vode i stakla, određivanje žarišne daljine konvergentne leće, dokaz Brewsterovog zakona te dokaz Malusovog zakona. Odabrani pokusi su prikazani u provedbi u
laboratoriju, odnosno uživo i pomoću simulacija. Prikazane su učeničke pretkoncepcije u području optike kao i najbolji način rješavanja istih.This master thesis briefly describes the laws of geometrical and physical optics, the experiments planned for performance in class and the simulations of four selected experiments from these areas. The selected experiments are: determination of the
refractive index of water and glass, determination od the focal lenght of a converging lens, proof of Brewster's law and proof of Malus' law. Selected experiments are presented in the laboratory, i.e. live and using simulations. Students' preconceptions in the field of optics are presented, as well as the best way to solve them
Phase transition in Blume Capel model
No full textBlume-Capel model verzija je Isingova modela magneta, a koristi se za opisivanje magnetskih krutina koje u sebi sadrže šupljine ili kao model za proučavanje razdvajanja faza u mješavinama 4He i 3He . U odsustvu vanjskog magnetskog polja, Blume-Capel spin-1 model pokazuje postojanje faznog prijelaza. Ovaj rad započinje opisom nekih fizičkih pojmova koji će imati veliki značaj u daljnjoj razradi, a potom se opisuju Isingov i Blume-Capel model. Postoji nekoliko načina rješavanja Blume-Capel modela, a u ovom se radu koristi jedna od metoda koja nosi naziv metoda matrice transfera. Pomoću nje ćemo izračunati slobodnu energiju i
korelacijsku funkciju za nekoliko parametara ovog modela.The Blume-Capel model is a version of the Ising model for magnetic materials, and it is used to describe magnetic solids that contain cavities or as a model for studying phase separation in 4He and 3He mixtures. In the absence of an external magnetic field, the Blume-Capel model shows the existence of a phase transition. This paper begins with a description of some physical
concepts that will be of great importance in further elaboration, followed by a description of the Ising and Blume-Capel models. There are several ways to solve the Blume-Capel model, and this paper provides the description of a method named the transfer matrix method. With its help, we will calculate the free energy and the correlation function for several parameters of this model
SCANNING ELECTRON MICROSCOPY IN LOW VACUUM CONDITIONS (LOW VACUUM SEM)
No full textSkenirajući elektronski mikroskop (SEM) postao je nezamjenjiv alat za analizu različitih materijala, uključujući metale, polimere, keramiku i drvo. Njegove bitne komponente uključuju izvor elektrona, elektromagnetske leće i detektore. JEOL SEM, moderan i široko korišten instrument, služi za akademska i industrijska istraživanja, kontrolu kvalitete i različite znanstvene primjene. U ovom radu usporedili smo SEM slike dobivene u području niskog vakuuma (LV SEM) i visokog vakuuma (HV SEM) koristeći JSM-IT200 JEOL SEM za skeniranje slabo vodljivih uzoraka drva i natrijevog klorida pri različitim povećanjima i mjerilima. Rezultati su otkrili da je HV SEM proizvodio svjetlije, ali zamućene slike, posebno za drvo, dok je LV SEM nudio višu rezoluciju, posebno za drvo. Nakon povećanja (x50 do x500), jako uvećani uzorci postali su mutniji i manje detaljni. LV SEM pokazao je značajno bolje karakteristike površine. Stoga je LV SEM dosljedno proizvodio vrhunske slike slabo vodljivih uzoraka, osobito pri malom povećanju,što je tema ovog završnog rada.The Scanning Electron Microscope (SEM) has become indispensable for analyzing various materials, including metals, polymers, ceramics, and wood. Its essential components include the electron source, electromagnetic lenses, and detectors. The JEOL SEM, a modern and widely used instrument, caters to academic and industrial research, quality control, and diverse scientific applications. This study compared low vacuum SEM (LV SEM) and high vacuum SEM (HV SEM) using the JSM-IT200 JEOL SEM to scan poorly conductive wood and sodium chloride samples at different magnifications and scales. The results revealed that HV SEM produced brighter but blurred images, particularly for wood, while LV SEM offered higher resolution, especially for wood. Upon magnification (x50 to x500), highly magnified samples became more blurred and less
detailed. LV SEM exhibited significantly better surface features. Thus, LV SEM consistently produced superior images of poorly conductive samples, particularly at low magnification, making it the preferred choice for this study