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ANALYSIS OF DRINKING WATER QUALITY IN THE AREA OF OSIJEK-BARANJA COUNTY DURING 2019
No full textVoda čovjeku predstavlja osnovi resurs za preživljavanje. Industrijalizacija i povećanje ljudske populacije
dovodi do onečišćenja i prekomjernog iskorištavanja, a klimatske promjene sve više smanjuju dostupnost i
kvalitetu vode. Kako bi voda za piće bila zdravstveno ispravna, prolazi kroz pogon za obradu sirove vode te se
njezina kvaliteta mora svakodnevno kontrolirati. Kako bi se ustanovila zdravstvena ispravnost vode za piće na
području Osječko-baranjske županije, u uzorcima vode s 6 lokacija analizirani su parametri: aerobne mezofilne
bakterije inkubirane pri 36 °C i 22 °C, bakterija Escherichia coli, slobodni klor, temperatura, pH, mutnoća i
boja. S ciljem usporedbe kvalitete vode obzirom na razdoblje godine, analize su provedene u zimskom i ljetnom
periodu 2019. godine. Testirane lokacije bile su različito udaljene od pogona za preradu sirove vode, kako bi
se ispitala moguća lošija kvaliteta na udaljenijim lokacijama. Rezultati pokazuju da je voda na istraživanom
području bila zdravstveno ispravna, ali lošije kvalitete tijekom ljetnog perioda. Obzirom na udaljenost od
pogona za preradu sirove vode, značajna razlika ustanovljena je analizom slobodnog klora što predstavlja veći
rizik za razvoj bakterija u vodi.Water is a basic resource for human survival. Industrialization and the increase of the human population are
leading to pollution and overexploitation, and climate change is significantly affecting the availability and
quality of water. Drinking water safety is insured by raw water processing in water treatment plants and its
quality must be checked daily. In order to test the health safety of drinking water in Osijek-Baranja County,
water samples were collected from 6 locations and following parameters were analyzed: aerobic mesophilic
bacteria incubated at 36 ° C and 22 ° C, Escherichia coli, free chlorine, temperature, pH, turbidity, and colour.
Study was conducted during winter and summer of 2019 allowing assessment of the water quality depending
on the period of the year. Locations near and far from raw water treatment plant were selected, in order to
determine possibility of poor water quality at more distant locations. The results indicate health safety of
drinking water in the tested area, but slight deterioration of water quality was observed during the summer
period. Given the distance from the raw water treatment plant, a significant difference in concentration of free
chlorine was found which poses a higher risk for the development of bacteria in the water at more distant
locations
Plant cell culture as a bioreactor for the production of secondary metabolites
No full textPomoću kulture biljnih stanica mogu se proizvoditi biljni sekundarni
metaboliti koji se prirodno u biljkama nalaze u malim količinama i vrlo su komplicirani i neisplativi za
ekstrahirati. U bioreaktorima se sekundarni metaboliti mogu proizvoditi u velikim količinama. Pomoću raznih
strategija poboljšanja kultura biljnih stanica može se povećati količina akumuliranih sekundarnih metabolita.
Najvažniji faktor povećanja akumulacije sekundarnih metabolita u biljkama su elicitori.Plant cell culture can be used to produce plant secondary metabolites which are found in small
amounts in plants and are very complicated and unprofitable to extract. In bioreactors secondary metabolites
can be produced in large quantities. There are various strategies to improve plant cell cultures that can increase
the amount of accumulated secondary metabolites. The most important factor in increasing the accumulation
of secondary metabolites in plants are elicitors
THE CHARACTERISTICS OF MEDICINAL PLANTS IN ETHNOMEDICINE OF ĐURĐEVAC AREA
No full textIstraživanje tradicionalne primjene biljaka provedeno je u razdoblju od ožujka do listopada 2019. godine na
području Đurđevca i okolnih naselja. Istraživanjem je obuhvaćeno 27 ispitanika. Utvrđeno je da ispitanici koriste
ukupno 102 biljne vrste iz 44 porodice. Najveći broj vrsta pripada porodicama Rosaceae, Lamiaceae i Asteraceae.
Ispitanici koriste biljke u svrhu liječenja, prehrane, izrade kozmetičkih preparata i druge svrhe. Osim biljaka,
ispitanici prikupljaju 17 vrsta gljiva iz ukupno 7 porodica. Rezultati ukazuju da je potrebno provesti opsežnija
istraživanja kako bi se vrijedna znanja o uporabi biljaka očuvala.A survey of a traditional use of plants was conducted from March 2019 to October 2019 in Đurđevac and
the surrounding settlements. The survey involved 27 respondents. A total of 102 plant taxa belonging to 44 families
were recorded. The most prevalent were plants belonging to Rosaceae, Lamiaceae and Asteraceae families. They
are used as food and for medicinal, cosmetic and other purposes. Besides plants, respondents stated that they also
collect mushrooms; 17 taxa belonging to 7 families in total. The results of this study indicate that further research
is needed in order to preserve valuable knowledge about the use of plants
Rheological Characteristics of Ice Cream with the Addition of Turmeric and Black Pepper
No full textSladoled je kompleksna namirnica specifičnog načina proizvodnje. Cilj ovog rada bio je ispitati utjecaj dodatka praha kurkume i crnog papra u različitim udjelima na reološka svojstva sladoledne smjese. Također, ispitan je utjecaj navedenih začina na povećanje volumena te tvrdoću sladoleda. U ovom radu proizveden je kontrolni uzorak sladoleda te sladoled s dodatkom 0,5 %, 1,0 % i 2,0 % kurkume sa ili bez dodatka 0,02 % crnog papra. Rezultati analize reoloških parametara ukazali su na trend povećanja viskoznosti proporcionalno s povećanjem udjela kurkume (i papra). Najveću viskoznost pokazala je sladoledna smjesa s 2,0 % kurkume i 0,02 % papra (UK2P), a najmanju kontrolni uzorak. Dodatak kurkume (i papra) utjecao je na smanjenje tvrdoće sladoleda, pa je kontrolni uzorak imao najveće vrijednosti izmjerene tvrdoće. Analizom povećanja volumena sladoleda tijekom proizvodnje utvrđen je linearan porast volumena uslijed povećanja koncentracije kurkume. Dodatak papra dodatno je utjecao na povećanje volumena.Ice cream is a complex food, obtained by a specific manufacturing process. The aim of this study was to investigate the influence of turmeric powder and black pepper addition in different proportions on ice cream mixes rheological properties. Furthermore, samples were analysed for overrun and hardness. In this study, control ice cream, as well as enriched ice creams were manufactured by adding turmeric powder at levels 0,5%, 1,0%, and 2,0% (with or without black pepper). The results of the study showed that the addition of turmeric powder and black pepper caused an increase in viscosity. The highest viscosity level had a sample with 2.0% turmeric powder and 0.02% black pepper (UK2P), while the lowest level had the control sample. Turmeric (and black pepper) addition to ice cream caused a hardness decrease, so the control sample had the lowest value for hardness. The analysis of the volume increase during the production of ice cream showed a linear increase in air incorporation due to an increase in turmeric concentration. The addition of black pepper additionally influenced the increase in overrun values
Changes in Melting Rates During Storage of Turmeric and Black Pepper Flavoured Ice Cream
No full textU proizvodnji sladoleda sve se više dodaju funkcionalni dodaci, koji osim terapijskih svojstava utječu i na kvalitetu sladoleda tijekom čuvanja. Zadatak rada bio je ispitati promjene brzine topljenja tijekom skladištenja mliječnog sladoleda s dodatkom praha kurkume i papra u različitim udjelima. Sladoled se proizvodio u laboratorijskom uređaju Nemox GELATO 5K CREA i-Green, zatim su se kontrolni uzorak i uzorak sladoleda s dodatkom 0,5 %, 1,0 % i 2,0 % kurkume u prahu (bez i s dodatkom 0,02 % papra) čuvali u zamrzivaču. Uzorci su skladišteni na -18 °C i -32 °C. Nakon jednog, dva i tri mjeseca skladištenja mjerila se brzina topljenja sladoleda, indeks zadržavanja oblika i površine sladoleda metodom računalne analize slike, promjena suhe tvari i pH vrijednosti. Fotografije uzoraka napravljene tijekom ispitivanja u fiksnim vremenskim intervalima obrađene su pomoću ImageJ programa. Primjenom gravimetrijske metode topljenja, zaključuje se da su sladoledi s dodatkom kurkume i papra imali manju brzinu topljenja i produljeno vrijeme topljenja. Analizom indeksa zadržavanja oblika stupića sladoleda zamjećuje se da veći dodatak začina bolje utječe na zadržavanje oblika. Nakon tri mjeseca skladištenja došlo je do blagog pada pH vrijednosti i porasta udjela suhe tvari, a uočena je i sporija dinamika topljenja, osobito kod uzoraka skladištenih na nižoj temperaturi.In the production of ice cream, functional additives are increasingly being added, which, in addition to therapeutic properties, can significantly affect the quality of ice cream during storage. This study aimed to examine the changes in the melting rate during storage of milk ice cream with the addition of turmeric powder and black pepper in different proportions. Ice cream was produced in the Nemox GELATO 5K CREA i-Green laboratory device. Control sample and samples with 0.5%, 1.0%, and 2.0% turmeric powder (without and with the addition of 0.02% black pepper) were stored in a freezer for three months at -18 °C and -32 °C. After storage, the melting rate of ice cream, as well as the retention and shape index of ice cream were analyzed using the computer image analysis method. Furthermore, the changes in dry matter and pH values were determined during the storage. It can be concluded that samples with turmeric (and black pepper) addition had a lower melting rate and higher melting times. In addition, enrichment of samples with turmeric and black pepper, especially in higher concentrations, resulted in better shape and surface retention during melting. The pH values slightly decreased, and dry matter content increased during the storage. After three months of storage, a slower melting dynamic was observed, especially in samples stored at lower temperatures
Value-added bioproducts from microalgae and their uses
No full textMikroalge su fotosintetski organizmi mikroskopskih dimenzija koji naseljavaju
sve vodene biotope na Zemlji. U današnje vrijeme sve više privlače znanstvenu pozornost
prvenstveno kao obnovljivi izvor energije u proizvodnji biogoriva, ali jednako tako i zbog
niza visokovrijednih spojeva koje sadrže u svojim stanicama. Cilj ovog rada je pregledno
iznijeti aktualne spoznaje vezane uz vrste visokovrijednih bioprodukata dobivenih iz
mikroalgi, postupke proizvodnje i njihovu upotrebu. Pojedine vrste mikroalga sadrže
velike količine klorofila i karotenoida (luitein, astaksantin, β-karoten , zeaksantin), neke
vrste su izuzetno bogate antioksidansima kao što su likopen i fikobiliproteini, a neke vrste
su posebno bogate sterolima, proteinima, peptidima, amino-kiselinama i/ili polifenolima.
Proizvodnja navedenih bioprodukata odvija se u biorafinerijama. Visokovrijedni produkti
mikroalga upotrebljavaju se u ljudskoj prehrani, kao hrana za životinje, te u farmaceutskoj
i kozmetičkoj industriji. Sveukupno, potencijali mikroalga kao visokovrijedne sirovine su
veliki te su intenzivna istraživanja njihove moguće primjene u raznim područjima.Microalgea are photosynthetic organisms of microscopic dimensions
which inhabit all water biotopes on Earth. Today they attract the attention of scientists
mainly as a source of renewable energy in the form of biofuel, and for a multitude of
value-added compounds that can be found in their cells. The objective of this work is to
clearly present the current findings related to the value-added bioproducts extracted from
microalgea, their cultivation and use. Some species of microalgea contain large amounts of
chlorophyll and carotenoids (lutein, astaxanthin, β-carotene, zeaxanthin), some are very
rich in antioxidants such as lycopene and ficobiliproteins, while other species contain a lot
of sterols, proteins, peptides, amino-acids and/or polyphenols. The production of the
aforementioned bioproducts is conducted in biorefineries. Value-added products gained
from microalgea are used as human food, animal feed, in the pharmaceutical industry and
in the cosmetic industry. All in all, the potential of microalgea as a value-added raw
material is exceptional as research for their potential use in different fields intensifies
Application of Computer Vision for Determining Melting Properties of Ice Cream
No full textBudući da je sladoled unutar kategorije smrznutih mliječnih deserata proizvod koji se najviše konzumira, cilj je dobiti što kvalitetniji proizvod. Topljivost sladoleda je njegova vrlo bitna karakteristika te se najčešće kao pokazatelj određuje brzina topljenja. U ovom radu je za analizu svojstava topljenja korišteno sedam različitih uzoraka sladoleda sa i bez dodataka. Uz gravimetrijsku metodu za određivanje svojstava topljivosti primijenjene su i relativno novije metode računalne analize slike, pomoću kojih se određuju svojstva zadržavanja oblika odnosno svojstva širenja sladoleda. Rezultati dobiveni trima različitim metodama su uspoređeni kako bi se dobio uvid u podudarnost metoda. Mliječni sladoled bez dodataka pokazuje svojstva bržeg početka topljenja i veće brzine topljenja, u usporedbi sa ostalim uzorcima. Najdulje zadržavanje oblika sladoleda tijekom topljenja zabilježeno je kod uzoraka s najvišim udjelom dodataka, dok je trend najbržeg širenja otopljenog sladoleda primijećen kod uzoraka bez ili s manjim udjelom dodataka. Podaci za topljenje sladoleda primjenom računalne analize slike pokazuju vrlo dobro slaganje s rezultatima dobivenim gravimetrijskom metodom, što ukazuje na to da je moguća primjena ove metode u ispitivanju svojstava topljenja sladoleda.Since ice cream is the most consumed product within the category of frozen dairy desserts, the goal is to get the highest quality product. The melting of ice cream is its very important characteristic, and the rate of melting is usually determined as an indicator. In this study, seven different samples of ice cream with or without supplementation were used to analyse the melting properties. In addition to the gravimetric method for determining melting properties, relatively newer methods of computer vision analysis were applied, which determine the retention of the shape and the spreading of melted ice cream. The results obtained by three different methods were compared in order to gain a better insight into the concordance of the methods. Milk ice cream without the addition showed the fastest start of melting, and a higher melting rate, compared to the other samples. The longest retention of the ice cream shape during melting was recorded for samples with the highest content of spices, while the trend of the fastest spread of melted ice cream was observed in samples with no or lower spices content. Ice cream melting data using computer vision analysis show a very good agreement with the results obtained by the gravimetric method, which indicates that this method can be used to test the melting properties of ice cream
Measuring Electromagnetic Wave Propagation Transmission Parameters Through Traditionally Constructed Buildings
No full textThis paper examines the potential for shielding against electromagnetic (EM) radiation in traditional buildings. The primary objective is to evaluate how effectively these buildings can reduce the intensity of the electric field from external sources, while also identifying the factors that influence this reduction, such as geometry, structure, and the characteristics of EM waves. Measurements were conducted on the transmission parameter S21, which indicates how EM waves propagate through the walls of residential buildings constructed using traditional methods. The buildings analyzed were made from wood, rammed earth, raw bricks blended with straw (known in Croatian as ćerpič), and baked bricks, which served as the reference material. During the measurements, conditions such as the thickness, humidity, and temperature of both the walls and the surrounding environment were carefully controlled. The buildings represented traditional construction styles typical of Croatia and most of Central and Eastern Europe. The results indicate that structures made from rammed earth and raw bricks with added straw significantly decrease the transmission of EM wave energy compared to those made from wood and baked bricks. It is important to note that the walls of wood buildings were considerably thinner than those made from the other materials tested. Additionally, both the moisture content and thickness of the walls contributed significantly to reducing transmission parameters. These findings support the use of these traditional materials for constructing environmentally friendly buildings, while also suggesting the need for further architectural design and testing. Since this research does not cover all types of traditionally constructed buildings—such as stone houses, wicker structures, and dugouts—future studies will aim to expand this investigation to include a broader variety of traditional building styles
e-Services of the Ministry of the Interior of the Republic of Croatia
No full textOvaj rad proučava e-usluge Ministarstva unutarnjih poslova Republike Hrvatske (MUP RH) koje su dostupne građanima i pravnim osobama za obavljanje raznih administrativnih postupaka putem interneta. E-usluge omogućuju korisnicima da brzo i jednostavno podnesu zahtjeve za osobne dokumente, prijave ili promijene prebivalište, provjere status dokumenata, te pristupe informacijama vezanim za osobnu sigurnost i upravne poslove. U radu se analizira uloga ovih usluga u poboljšanju dostupnosti i učinkovitosti javne uprave, s posebnim naglaskom na tehničke izazove, sigurnosne aspekte i pravnu regulativu. Naglašava se važnost digitalne transformacije javne uprave, koja ne samo da pojednostavljuje svakodnevne postupke, već doprinosi i smanjenju administrativnog opterećenja građana i poslovnih subjekata. Rad također istražuje utjecaj e-usluga na transparentnost i modernizaciju upravnih procesa u Hrvatskoj, kao i na prilagodbu MUP-a suvremenim potrebama građana.This paper examines the e-services provided by the Ministry of the Interior of the Republic of Croatia (MUP RH) that allow citizens and legal entities to complete various administrative processes online. E-services enable users to quickly and easily apply for personal documents, register or change their residence, check the status of their applications, and access information on personal security and administrative matters. The paper analyzes the role of these services in improving the accessibility and efficiency of public administration, with a special focus on technical challenges, security issues, and legal regulations. Emphasis is placed on the importance of digital transformation in public administration, which not only simplifies everyday procedures but also reduces the administrative burden on citizens and businesses. The paper further explores the impact of e-services on transparency and modernization of administrative processes in Croatia and on adapting the Ministry to the modern needs of its citizens
Types of Public Procurement Procedures and an example of a Procedure in KOMUNALAC DAVOR d.o.o.
No full textKOMUNALAC DAVOR d.o.o. je trgovačko društvo u vlasništvu Općine Davor 100%. Osnovna djelatnost društva je sakupljanje neopasnog otpada. Obveznik je provođenja postupaka javne nabave kao i drugi javni naručitelji u Republici Hrvatskoj prema Zakonu o javnoj nabavi koji uređuje. Ovaj rad analizira vrste postupka javne nabave s naglaskom na otvoreni postupak javne nabave male vrijednosti. Rad pruža pregled zakonskog okvira javne nabave u Republici Hrvatskoj, objašnjava ključne pojmove i procesne korake te definira kriterije za primjenu pojedinih postupaka. Poseban dio rada posvećen je praktičnom primjeru javne nabave male vrijednosti u trgovačkom društvu KOMUNALAC DAVOR d.o.o. kroz analizu stvarnog postupka, uključujući pripremu dokumentacije, procjenu ponuda i donošenje odluke o odabiru. Zaključno, rad ističe važnost transparentnosti, učinkovitosti i poštivanja zakonskih odredbi u svim fazama postupka javne nabave.KOMUNALAC DAVOR is a company 100% owned by the Municipality of Davor. Its primary activity is the collection of non-hazardous waste. The company is obligated to conduct public procurment procedures, like other contracting authorities in Republic of Croatia, in accordance with the Public Procurement act. This graduate analyzes the types of public procurement procedures, focusing on the open procedure for small-value procurement. It prowides an overview of the legal framework for public procurement in the Republic of Croatia, explains key terms and procedural steps, and defines the criteria for applying specific procedures. A special section of the paper is dedicated to a practical example of small-value procurement in the company KOMUNALAC DAVOR d.o.o., through the analysis o fan actual procedure, including the preparation of documentacion, bid evaluation, and decision-making. In conclusion, the paper highlights the importance of transparency, efficiency, and compliance with legal provisions at all stages of the public procurement process