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Sveučilišni diplomski studijski program Primijenjene geologije i geološkog inženjerstva : obrazac 1 : elaborat o studijskom programu
No full textRedoximorphic features as indicators of soil water regime
No full textRežim vlaženja tla, kao jedna od ključnih komponenti njegove ukupne plodnosti, odnosi se na količinu, zadržavanje i kretanje vode u tlu. Umjesto skupim i/ili dugotrajnim mjerenjima, on se može procijeniti na terenu, i to putem opisa morfoloških svojstava tla. Prekomjerno vlažena tla imaju specifičnu morfologiju, zbog koje se nazivaju hidromorfnima. Takva njihova morfologija proizlazi iz redoksimorfnih značajki (RMZ), koje se stvaraju redukcijom, premještanjem i oksidacijom oksida željeza i mangana. Hidromorfna tla su uglavnom glejna i pseudoglejna tla (ali i oglejena fluvijalna tla), koja su prekomjerno vlažena podzemnim, oborinskim i/ili poplavnim vodama. U skladu s njihovom globalnom rasprostranjenošću, morfologija tih tala se često opisuje i analizira korištenjem različitih pojmova i kriterija. To otežava usporedbu i klasifikaciju hidromorfnih tala, kao i njihovu upotrebu ili popravak. Ovaj pregledni rad opisuje i uspoređuje uobičajene RMZ, objašnjavajući mehanizme njihova nastanka. Zatim predlaže revidirane hrvatske pojmove za ove značajke, skovane u skladu s onima koje koriste međunarodni sustavi WRB-FAO i/ili Soil Taxonomy. Nadalje, rad se kritički osvrće na kriterije i pravila, koja se koriste za dijagnosticiranje RMZ prilikom klasifikacije hidromorfnih tala. Konačno, ovaj rad pokazuje da metodološki ispravan opis RMZ može pružiti brz uvid u ključne parametre režima vlaženja tla, kao što su mjesto i trajanje zasićenja tla vodom, podrijetlo viška vode u tlu, recentnost prekomjernog vlaženja tla, itd. Međutim, ovisno o ciljevima istraživanja i/ili prisutnim uvjetima u tlu, terenski opis profila tla možda neće uvijek moći u potpunosti zamijeniti kontinuirano terensko praćenje režima vlaženja tla i/ili laboratorijske i mikromorfološke analize tla.Soil water regime, as one of the key components of soil fertility, refers to the quantity, retention, and movement of soil water. Rather than through expensive and/or time-consuming measurements, it can be assessed from the fieldobservable morphological properties in the soil profile. Excessively wetted soils have a specific morphology, and are therefore often referred to as hydromorphic. Their morphology is caused by various soil redoximorphic features (RMFs), resulting from the reduction, translocation, and oxidation of iron and manganese oxides. Hydromorphic soils largely comprise Gleysols and Stagnosols (along with Gleyic Fluvisols) that are excessively wetted by groundwater, precipitation and/or flooded water. Their morphology is often described/analyzed with different terms/criteria in line with their global distribution. This complicates the comparison and classification of such soils and thus their use or reclamation. This review paper describes and compares common RMFs and explains their formation. It then proposes the revised Croatian terms for these features, which are in line with the terms used in the international soil classification systems of WRB and/or Soil Taxonomy. Furthermore, the criteria/rules used for diagnosing RMFs when classifying hydromorphic soils are critically reviewed. Finally, it is shown that a methodologically sound RMFs description can provide a quick insight into the crucial soil water regime parameters, such as location and duration of soil saturation, the origin of the excess soil water, recentness of excessive soil wetting, etc. However, depending on the research objectives and/or actual soil conditions, field soil description cannot always fully replace continuous field monitoring of the soil water regime and/or laboratory and micromorphological soil analyses
Određivanje polumjera zakrivljenosti fronte detonacijskoga vala ANFO eksploziva i njegova važnost u numeričkome modeliranju detonacije primjenom Wood-Kirkwoodova modela
No full textUnlike most military high explosives, which are characterized by an almost plane detonation front, ammonium nitratebased commercial explosives, such as ANFO (ammonium nitrate/fuel oil mixture) and emulsion explosives, are characterized by a curved detonation front. The curvature is directly related to the rate of radial expansion of detonation products in the detonation driving zone and the rate of chemical reactions, and it is one of the characteristics of nonideal explosives. The detonation theories used to model the nonideal behaviour of explosives require both reaction rate and rate of radial expansion to be known/specified as input data. Unfortunately, neither can be measured and what is mostly used is a link between these rates and parameters which can be more easily measured. In this paper, the Wood-Kirkwood approach of determination of radial expansion through the radius of detonation front curvature and the electro-optical technique for experimental determination of detonation front curvature of ANFO explosives is applied. It was shown that an experimentally determined radius of detonation front curvature vs charge diameter, incorporated in the Wood-Kirkwood detonation theory, can satisfactorily reproduce experimental detonation velocity-charge diameter data for ANFO explosives, especially when the pressure-based reaction rate law is also calibrated (D=1.3 and k=0.06 1/(μs/GPaD)).Za razliku od većine vojnih visokih eksploziva, koje karakterizira gotovo ravna fronta detonacijskoga vala, komercijalne eksplozive na bazi amonijeva nitrata, kao što su ANFO i emulzijski eksplozivi, karakterizira zakrivljena fronta detonacijskoga vala. Zakrivljenost je izravno povezana s brzinom kemijskih reakcija i brzinom radijalnoga širenja produkata detonacije u zoni pokretanja detonacije i jedna je od karakteristika neidealnih eksploziva. Teorije detonacije, koje se koriste za modeliranje neidealnoga ponašanja eksploziva, zahtijevaju da se kao ulazni podatci znaju/specificiraju i brzina reakcije i brzina radijalnoga širenja. Nažalost, ni jedno ni drugo ne može se izmjeriti, pa se najčešće koristi veza između tih brzina i parametara koji se mogu lakše mjeriti. U radu smo primijenili Wood-Kirkwoodov pristup određivanja radijalnoga širenja preko polumjera zakrivljenosti fronte detonacijskoga vala te mogućnost eksperimentalnoga određivanja zakrivljenosti fronte detonacije ANFO eksploziva elektrooptičkom metodom. Pokazalo se da tako određen polumjer zakrivljenosti fronte detonacijskoga vs promjera naboja, ugrađen u Wood-Kirkwoodovu teoriju detonacije, može na zadovoljavajući način reproducirati eksperimentalne podatke o brzini detonacije i promjeru naboja ANFO eksploziva, pogotovo sa zadovoljavajućom kalibracijom modela brzine reakcija ovisne o tlaku (D = 1,3 i k = 0,06 1/(μs/GPaD))
Citation rate challenges for a small journal indexed in Scopus and WoS – case study from Central Europe (Croatia), editorial view
No full textThe term “small journal” has been used for a journal published as a single journal or one of a few serials, mostly by an academic publisher. This case study showed the challenges that a journal must override to be indexed in Scopus and WoS, especially if Q1/Q2 are targeted. The number of submissions, and especially of the published papers, are not the most critical variables for an increase of journal citations. The most important is the further activity of researchers included in the paper’s authorship, their future publication rate and continuation of similar research, which implies the citations of previous works belonging to the same authors and/or research groups. The larger the number of papers per issue, the increased probability of such an event, but there is no linear correlation. Moreover, the editorial work, especially during the initial editorial screening of received submissions, makes the consequent reviewer’s work easier, faster, and of higher quality, which certainly increases the quality of publications and their further citation life. The cited half-life vs. cited half-life ratio in small journals would need to be less than one (here 0.25), making the published papers fast cited, with first citations coming early enough that they could fit in a three-year window, and be countable for the calculation of indexing measures like Citescore or the Impact Factor
Decarbonization of the gas transport system : master's thesis
No full textNegativan učinak klimatskih promjena, odnosno njihove posljedice predmet su rasprava već dugi niz godina. Budući da je energetski sektor zaslužan za većinu emisija stakleničkih plinova, neophodna je energetska tranzicija. Izravan prelazak s fosilnih goriva na obnovljivu električnu energiju je nepraktična i skupa opcija, stoga se javlja potreba dekarbonizacije plinskog sustava korištenjem niskougljičnih i obnovljivih plinova, odnosno biometana i vodika. Europska unija uvodi razne mjere kojima se potiče dekarbonizacija, počevši od Europskog zelenog plana preko Strategije EU-a za integraciju energetskog sustava i Strategije za vodik za klimatski neutralnu Europu do okvira Spremni za 55% i REPowerEU. Kako bi se željeni klimatski i energetski ciljevi doista ostvarili, Europska unija zakonodavnim okvirom ističe važnost korištenja novih plinova te prenamjene i/ili izgradnje infrastrukture za vodik. Europska unija vidi vodik kao važan energent budućeg energetskog miksa te je suradnjom nekoliko europskih operatora transportnog sustava započela izrada Smjernica za izgradnju vodikove infrastrukture. Iako utiskivanje biometana u postojeću plinsku mrežu ne predstavlja problem, utiskivanje vodika nije u potpunosti istraženo. Međutim, ulaganjem u znanost i istraživanje te inovacije i razvoj, proširuje se znanje o mogućnostima umješavanja vodika u tok prirodnog plina te o prenamjeni plinovoda za transport vodika. Smanjenje troškova proizvodnje zelenog vodika iz obnovljivih izvora energije u Europi potaknut će daljnji razvoj tržišta vodika i infrastrukture za njegovu primjenu.The negative effects of climate change and their consequences have been the subject of debate for many years. Since the energy sector is responsible for most of the greenhouse gas emissions, an energy transition is necessary. Switching from fossil fuels to renewable energy is an impractical and expensive option, so there is a need to decarbonize the gas system using low-carbon and renewable gases, ie biomethane and hydrogen. The European Union is introducing a variety of measures to encourage decarbonisation, ranging from the European Green Deal through the EU Strategy for energy system integration and the Hydrogen Strategy for climate neutral Europe to the Fit for 55% and REPowerEU. In order to achieve the desired climate and energy goals, the European Union emphasizes in the legislative framework the importance of using new gases and repurposing and/or building new hydrogen infrastructure. The European Union sees hydrogen as an important energy source for the future energy mix, so several European transport system operators have participated in the development of European Hydrogen Backbone. Although the injection of biomethane into the existing gas network is not a problem, the injection of hydrogen has not been fully researched. However, by investing in science, research, innovation and development, the knowledge about the possibilities of hydrogen injection in the natural gas grid and repurposing of gas pipelines for hydrogen transport is expanded. Reducing the cost of producing green hydrogen from renewable energy sources in Europe will encourage further development of the hydrogen market and its infrastructure
Lithofacies in the upper part of the Promina Mountain : master's thesis
No full textU ovom radu istraživani su, opisani i interpretirani litofacijesi Prominskih naslaga vršnog dijela planine Promine. Na istraživanom području dokumentirana je izmjena krupnozrnastih klastita – vapnenačkih konglomerata/kalkrudita, srednjezrnastih karbonatnih klastita - kalkarenita te mješovitih sedimenata - kalcitičnih muljnjaka/madstona. Terenskim radom snimljen je geološki stup PRO-21 te su izdvojeni i opisani litofacijesi. Mikropetrografski su potom determinirani i detaljno opisani terenski izdvojeni litofacijesi. Raspravljeni su i interpretirani okoliši taloženja.Lithofacies of the Promina Beds situated at the top of the Promina Mt. were investigated, described, and interpreted. Sedimentary sequences of coarse-grained clastics – carbonate conglomerates/calcrudites, carbonate clastics – calcarenites and mixed clastic-carbonate rocks - calcareous mudstones, were determined in the studied area. The result of geological field work, combined with the micropetrographic analysis of rock samples, is the geological column PRO-21, showing determined lithofacies and their characteristics. Attributed sedimentary environments were also discussed and interpreted
Petrography and geochemistry of granitoids and related rocks from the pre-Neogene basement of the Slavonia-Srijem Depression (Croatia)
No full textThe pre-Neogene basement of the Slavonia-Srijem Depression (eastern Croatia) is composed of various types of igneous, metamorphic and sedimentary rocks. Here we present the petrography and geochemistry of a heterogenous group represented by two types of alkali granite, granite, syenite, rhyolite and orthogneiss. The alkali granite type 1 has an A-type geochemical affinity: a ferroan character, high alkali content, high concentration of rare earth elements (REE3+), Rb, Zr, Nb and Y, and low CaO, MgO, P2O5, Ba, Sr and Eu contents. The syenite has similar characteristics, but displays enrichment in Ba, K, Eu and Zr, which could be a consequence of feldspar and zircon accumulation. The alkali granite type 2 is an A-type granite but differs from the alkali granite type 1 in having lower K2O and Rb, accompanied by higher Na2O and Sr concentrations, possibly resulting from alteration or a different parental magma/evolutionary process. The granite and rhyolite are distinguished from both types of alkali granite by their magnesian character, lower Zr, Nb and Y concentrations, less pronounced Eu negative anomaly, as well as higher Ba, Sr and LREE/HREE. The orthogneiss displays differences in major element chemistry compared to the alkali granite type 1, but has similar trace element and REE patterns. The alkali granites are characterized by Y/N
Structural analysis of Petrova gora : master's thesis
No full textStrukturno-geološka istraživanja koja su prikazana u ovom diplomskom radu dio su projektnih aktivnosti na HRZZ znanstveno-istraživačkom projektu HyTheC. Cilj ovog rada bio je na temelju postojećih te novoprikupljenih podataka u sklopu strukturno-geoloških istraživanja prikazati strukturno-geološke odnose u podzemlju na području istraživanja. Prikupljeni strukturni podaci organizirani su u GIS bazu podataka, korišteni su za izradu geoloških profila te su prikazani stereografskim prikazom pomoću računalnog programa. Strukturna građa podzemlja analizirana je kroz šest geoloških profila koji su okomiti na strukture. Profili su korišteni za izradu konceptualnog 3D modela koji je izrađen u programu Petroleum Experts Move. Na temelju provedenih istraživanja i prikupljenih podataka mogu se izdvojiti tri kinematske faze koje su utjecale na razvoj istraživanog područja. Tijekom gornjokredne kompresijske faze nastajali su sustavi reversnih rasjeda, tijekom miocena, u fazi ekstenzije, nastali su sustavi normalnih rasjeda dok su u završnoj fazi tijekom gornjeg miocena, pliocena i kvartara, u fazi kompresije, reaktivirani reversni rasjedi, a normalni rasjedi su tektonski invertitrani. Kinematske faze imale su značajan utjecaj na geotermalni razvoj prodručja. S obzirom na inicijalnu subdukciju, odnosno suturiranje duž Savske suturne zone i stanjenu koru, može se pretpostaviti da se dio topline rasjednim sustavima iz Savske suturne zone prenosi prema trijaskom vodonosniku koji periklinalno okružuje permske naslage Petrove gore.The structural-geological research presented in this Thesis is a part of the activities of the HRZZ scientific project HyTheC. The objectives of this work were focused on determination of structural relations of the study area subsurface based on existing and newly collected as a part of project structural-geological investigations. The collected structural data were organized into a GIS database, used to construct geological cross-sections and presented using stereographic projection. The structure of the subsurface was analyzed through six constructed geological profiles oriented perpendicular to the structures. Geological profiles were used to construct a conceptual 3D model in the Petroleum Experts Move software. Based on the collected data, three kinematic phases can be distinguished that influenced the development of the research area. During the Upper Cretaceous compressional phase, reverse fault systems were created, whereas in the Miocene extension phase, normal fault systems were created. During the Upper Miocene, Pliocene and Quaternary, in the third phase, the compression phase, reverse and normal faults were structuraly reactivated and tectonically inverted. Kinematic phases had a significant impact on the geothermal development of the area. Considering the initial subduction depth and the thinned crust, it can be assumed that the heat from the Sava Suture Zone is transferred via fault systems towards the Triassic aquifer that periclinally surrounds the Permian deposits of Petrova gora
Modeling oil spill weathering and movement on the surface of the sea : master's thesis
No full textNakon izljeva ugljikovodika na određenu površinu, nastaje naftna mrlja. Na nastalu naftnu mrlju djelovat će niz fizikalnih i kemijskih procesa i uzrokovati zagađenje mrljom zahvaćenog okoliša. Službe za sanaciju izlivenih ugljikovodika moraju biti spremne što preciznije pretpostaviti smjer kretanja nastale naftne mrlje kako bi sanacija nastalog zagađenja bila što uspješnija. Za to im služi niz računalnih programa koji modeliraju trajektoriju kretanja naftne mrlje na morskoj površini pod djelovanjem procesa starenja naftne mrlje i djelovanja atmosferilija.An oil slick is formed after the spill of hydrocarbons on the surface of the sea. A series of physical and chemical processes will act on the formed oil slick and cause the pollution of the environment that is affected by the slick. Oil spill response services must be prepared to assume the direction of movement of the oil slick as precisely as possible so that the cleanup of the existing pollution is as successful as possible. For that to happen, the cleanup services are assisted by a series of computer programs that model the trajectory of the movement of the oil slick on the sea surface, which is under the influence of the weathering processes and the effects of atmospheric conditions