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Systems for extraction and filtration of fumes and gases in welding
No full textOdržavanje čistog zraka u industriji zavarivanja ključno je za sprječavanje ozbiljnih zdravstvenih problema/rizika među zavarivačima, povećanje produktivnosti i održavanje usklađenosti sa sigurnosnim standardima. Izloženost dimu od zavarivanja, koji je poznat kao kancerogen, zahtijeva sigurno i usklađeno radno okruženje za zaštitu zavarivača.
Bez obzira radi li se o maloj radionici za zavarivanje, zavarivanju na terenu ili velikoj automatiziranoj tvornici, treba se posvetiti pružanju rješenja za odvod dima. Bez obzira na korištenu metodu zavarivanja, bila ona robotska, cobot ili ručna, učinkovita ekstrakcija dima pri zavarivanju je imperativ za zaštitu zavarivača, održavanje produktivnosti i usklađenost s pravilima i propisima. Čimbenici koji uključuju metodu sakupljanja, dizajn industrijske ventilacije, odabir medija za filtriranje i pravilne prakse servisiranja/održavanja doprinose tome koliko ekstrakcija dima može biti energetski učinkovita.Ensuring clean air in the welding industry is critical to preventing serious health
problems/risks among welders, increasing productivity and maintaining compliance with safety
standards. Exposure to welding fumes, which is a known carcinogen, requires a safe and
compliant work environment to protect welders.
Whether it is a small welding shop, field welding or a large, automated factory, it should be
committed to providing fume extraction solutions. Regardless of the welding method used, be
it robotic, cobot or manual, effective welding fume extraction is imperative to protect welders,
maintain productivity and comply with rules and regulations. Factors including collection
method, industrial ventilation design, filter media selection, and proper service/maintenance
practices contribute to how energy efficient fume extraction can be
Primjena monološke metode pripovijedanja na poučavanje izvornih govornika padežima hrvatskoga jezika
No full textTema je ovoga specijalističkog rada primjena monološke metode pripovijedanja u poučavanju padežima hrvatskog jezika izvornim govornicima. Cilj je rada istražiti učinkovitost i mogućnosti korištenja ove metode u razumijevanju i primjeni padeža te potaknuti angažiranost i motivaciju učenika. Analizom tradicionalnih pristupa podučavanju gramatike ističu se nedostaci učenja pravila i padežnih pitanja umjesto razumijevanja i primjene padeža u govornom i pisanom okruženju. Monološka metoda pripovijedanja pruža učenicima neizravno otkrivanje jezičnih zakonitosti i praktičnu primjenu stečenog znanja, emocionalno povezivanje s pričom, pamćenje jezičnih struktura te razvoj aktivnog slušanja i kreativnog izražavanja. Stoga se glavni dio rada temelji na opisu primjene metode u praksi i obuhvaća prikaz sati s autorskim pričama o antropomorfiziranim padežima, koje su upotpunjene dramskim vježbama i aktivnostima. Analiza provedene prakse naglašava važnost pričanja priča u nastavi kao efektivnoga pedagoškog alata koji potiče angažiranost, motivaciju i uspješan razvoj učenika. Pamćenje priča pruža učenicima trajno znanje koje mogu primijeniti poslije u drugim životnim situacijama.The topic of this specialist paper is the application of the monologue method of storytelling in teaching Croatian language cases to native speakers. The aim of the paper is to explore the effectiveness and possibilities of using this method in
understanding and applying cases and to stimulate the students' engagement and motivation. An analysis of traditional approaches to teaching grammar shows the shortcomings of learning rules and case questions instead of understanding and applying cases in both spoken and written environments. The monologic storytelling method provides students with an indirect discovery of linguistic regularities and a practical application of acquired knowledge, emotional connection with the story, memorization of language structures and the development of active listening and creative expression. Therefore, the main part of the paper is based on the description of the methods' application in practice and includes a presentation of lessons with author's stories about anthropomorphized cases, which are supplemented with drama exercises and activities. The conclusions of the conducted practice emphasize the importance of storytelling in class as an effective pedagogical tool which encourages the students' engagement, motivation and successful development. Additionally, memorizing stories provides students with lasting knowledge which they can later apply in various life situations
Electrochemical sensors for biomedical applications
No full textSenzori su uređaji ili naprave kojima je moguće ustanoviti postojanje mjerljivog svojstva te se pomoću njih utvrđuje kvantitativna vrijednost praćene fizikalne veličine. Rad elektrokemijskih senzora temelji se na prepoznavanju analita kroz aktivni sloj materijala koji sačinjava senzor, odnosno elektrokemijski senzori transformiraju učinak elektrokemijske interakcije analit – elektroda u koristan mjerljivi signal. Pregled razvoja analitičke kemije pokazuje kako unutar područja kemijskih senzora, najveći razvoj pokazuje područje elektrokemijskih senzora. Navedeni senzori imaju širok spektar primjene, a jedan od njih je i primjena u biomedicini. Elektrokemijski senzori koji se primjenjuju u biomedicini su posebni elektronički uređaji koji mogu pretvoriti biomedicinske signale u lako mjerljive električne signale. Biomedicinski senzori ključna su komponenta različitih medicinskih dijagnostičkih instrumenata i opreme. Razvoj i istraživanje biosenzora popularno je znanstveno i tehnološko područje na presjeku prirodnih i tehničkih znanosti (biologija, kemija, kemijsko inženjerstvo, znanost o materijalima, elektronika i fizika) u kojem je obavezan multidisciplinaran pristup. Svaki napredak u tom polju imat će veliki utjecaj na budućnost dijagnostike i liječenja bolesti. Područja personalizirane i preventivne medicine, dijagnostike i otkrića lijekova imat će pozitivan doprinos od novih senzorskih tehnologija.Sensors are devices by which it is possible to establish the existence of a measurable property and use them to determine the quantitative value of the monitored physical quantity. Electrochemical sensors principle is based on the recognition of analytes through the active layer of the sensor material, for example electrochemical sensors transform the effect of electrochemical interaction of analyte - electrode into a useful measurable signal. A review of the development of analytical chemistry shows that within the field of chemical sensors, the field of electrochemical sensors demonstrates the greatest development. That type of sensors has a wide range of applications, including the application in biomedicine. Electrochemical sensors used in biomedicine are special electronic devices that can convert biomedical signals into easily measurable electrical signals. Biomedical sensors are a key component of various medical diagnostic instruments and equipment. The development and research of biosensors is a popular scientific and technological field at the intersection of natural and technical sciences (biology, chemistry, chemical engineering, materials science, electronics and physics) in which a multidisciplinary approach is mandatory. Any progress in this field will have a major impact on the future of disease diagnosis and treatment. The fields of personalized and preventive medicine, diagnostics and drug discovery will have a positive contribution from new sensor technologies
Seismic Analysis of the Masonry Tower Ficarolo in Italy Using the Finite-discrete Elements Method : Master's Thesis
No full textU radu je prikazana analiza ponašanja zidanog tornja izloženog potresnom opterećenju uporabom kombinirane metode konačno-diskretnih elemenata. Za proračun su korištena 3 stvarna potresa i 4 rubna uvjeta. Numeričkom analizom provjerava se seizmička otpornost građevine i utvrđuje koji je način oslanjanja na podlogu najpovoljniji.The paper presents an analysis of the behavior of a masonry tower exposed to seismic loading using the combined method of finite-discrete elements. 3 real earthquakes and 4 boundary conditions were used for the calculation. Numerical analysis checks the seismic resistance of the building and determines which type of support on the ground is the most favorable
Preparation of activated sludge samples for chromatographic analysis of pollutants
No full textPraćenje onečišćivala u uzorcima najučinkovitije se postiže kromatografskim metodama. Međutim, da bi uzorak mogao biti analiziran spomenutom metodom potrebno ga je prethodno pripremiti i prevesti u oblik adekvatan za analizu. U ovom slučaju određivala su se onečišćivala u aktivnom mulju koji je nastao tijekom procesa biorazgradnje. Naime, proces biorazgradnje uobičajeno je sastavni dio postupka obrade otpadnih voda pri čemu nastaju velike količine aktivnog mulja. Biorazgradnja je proces tijekom kojeg različiti mikroorganizmi pretvaraju materijale u prirodne tvari koje potječu iz okoliša kao što su voda ili ugljikovi spojevi. Cilj ovog rada bio je razviti adekvatnu metodu pripreme uzoraka aktivnog mulja nastalog procesom biorazgradnje kako bi se odredila ostatna onečišćivala u spomenutom aktivnom mulju kromatografskom analizom. Onečišćivala praćena u ovom radu su ksenobiotici iz skupine antiparazitika (mebendazol, albendazol i febantel) i insekticida (klotianidin, acetamiprid i tiakloprid). Ksenobiotici pripadaju skupini mikroonečišćivala, odnosno spojevima koji se mogu naći u vodenim sustavima kao posljedica antropogenog utjecaja. Optimizirali su se uvjeti za ekstrakciju mućkanjem (vrijeme trajanja ekstrakcije, volumen otapala, broj okretaja i temperatura ekstrakcije) i ultrazvučnu ekstrakciju (način pripreme mulja, vrijeme trajanja ekstrakcije, volumen otapala, snaga ultrazvučne kupelji i temperatura ekstrakcije). Izabrano optimalno otapalo bila je smjesa otapala MeOH: ACN=50:50 (v:v) ukupnog volumena 5 mL.Monitoring of pollutants in samples is most effectively achieved by chromatographic methods. However, in order for the sample to be analyzed by the mentioned method, it should be prepared beforehand and translated into a form adequate for analysis. In this case, pollutants were determined in the activated sludge that was created during the biodegradation process. Namely, the biodegradation process is usually an integral part of the wastewater treatment process, where large amounts of activated sludge are produced. Biodegradation is the process during which various microorganisms convert materials into natural substances that originate from the environment such as water or carbon compounds. The goal of this work was to develop an adequate method of preparing samples of activated sludge produced by the biodegradation process in order to determine the remaining pollutants in the mentioned activated sludge by chromatographic analysis. The pollutants monitored in this work were xenobiotics from the group of antiparasitics (mebendazole, albendazole and febantel) and insecticides (clothianidin, acetamiprid and thiacloprid). Xenobiotics belong to micropollutants, compounds that can be found in water systems as a result of anthropogenic influence. The conditions for extraction by shaking (extraction time, solvent volume, number of revolutions and extraction temperature) and ultrasonic extraction (method of sludge preparation, extraction time, solvent volume, power of the ultrasonic bath and extraction temperature) were optimized. The optimal solvent chosen was the solvent mixture MeOH: ACN=50:50 (v:v), total volume 5 mL
The Effect of Adding Pieces of Cotton Textile Waste on Properties of Light and Fine-Grained Plain Concrete : Master's Thesis
No full textProizvodnja pamučnog donjeg rublja stvara određenu količinu otpada od pletenih tkanina. U ovom radu je ispitana mogućnost upotrebe otpada od pletenih pamučnih tkanina u betonu. U tu svrhu je napravljeno pet mješavina koje su imale dodatak tekstilnog otpada u količini od 1.7 i 3.5% ukupnog volumena te referentna mješavina bez dodatka tkanine. Na uzorcima se u svježem stanju mjeri obradivost a u očvrstlom stanju čvrstoća na savijanje i tlak, dinamički modul elastičnosti, gustoća, kapilarno upijanje i apsorpcija. Prikazana je usporedba dobivenih rezultata s rezultatima koji su ranije izrađeni i ispitivani na Katedri za građevinske materijale.Cotton underwear manufacture produces a significant amount of knitted fabric waste. The aim of this study is to examine the possibility of using cotton knit fabric waste in concrete. Therefore, there have been made five different mixtures that have had from 1,7% to 3,5% of the total textile waste volume and a reference mixture without adding any fabric. Workability has been measured during the samples' plastic state, while flexural strength and compression, dynamic modulus of elasticity, density and capillary absorption during their hardened state. In this study it is presented the comparison of the results obtained with those previously examined and obtained in the Department of Materials
Improving the assembly process by applying lean management tools
No full textU ovom radu opisan je koncept lean menadžmenta te su detaljnije objašnjeni temeljni principi i najčešće korišteni alati lean menadžmenta u autoindustriji. Posebna pozornost obratila se gubitcima koji se javljaju u proizvodnim procesima. Nakon teoretskog dijela prikazani su rezultati mjerenja količine vremena potrebnog za montažu automobila na odabranom primjeru iz prakse. Rezultati mjerenja potom su se analizirali te su identificirani gubitci koji se javljaju. Kako bi se smanjila potrebna količina vremena montaže napravljena je optimizacija montažne linije te su predložene daljnje mjere za unaprjeđenje.This thesis deals with the concept of Lean management and further explains its fundamental principles, as well as its most frequently used tools within the auto-industry. A particular emphasis is put on the losses that emerge during production. Following the theoretical concept of Lean management, this research shows measuring results where the object of question was the amount of time needed to assemble a car seen in the chosen example. The measuring results were consequently analysed and have identified the occuring losses. In order to reduce the amount of time needed for assembly, an optimisation o fan assembly line was produced and further developoing aspects were suggested
New Chinese herbal drugs (rhizoma et radice) in the eleventh edition of the European pharmacopoeia
No full textFitoterapija predstavlja glavni oblik prevencije i liječenja bolesti u sustavu tradicionalne kineske medicine koja se primjenjuje u Kini već stotinama godina, a u novije vrijeme joj i zapadna medicina pridaje na važnosti. Sa ciljem proširenja znanja u području fitofarmacije, teorijski je istraženo pet biljnih droga dobivenih od korijenja i podanaka kineskih ljekovitih biljaka: Belamcandae chinensis rhizoma, Cyathulae radix, Rehmanniae radix, Sanguisorbae radix i Scrophulariae radix. Pregledom stručne i znanstvene literature, za navedene biljne droge u radu je dan pregled dosadašnjih spoznaja o biljnim izvorima, tradicionalnoj primjeni, fitokemijskom sastavu te pretklinički i klinički dokazanim učincima kao i hrvatski prijevod pripadajućih monografija u aktualnom, 11. izdanju Europske farmakopeje.Phytotherapy is the main form of prevention and treatment of diseases in the system of traditional Chinese medicine, which has been applied in China for hundreds of years, and in recent times Western medicine has also given importance to it. With the aim of expanding the knowledge in the field of phytopharmacy, five herbal drugs obtained from the roots and rhizomes of Chinese medicinal plants were theoretically investigated: Belamcandae chinensis rhizoma, Cyathulae radix, Rehmanniae radix, Sanguisorbae radix and Scrophulariae radix. Through a review of professional and scientific literature, an overview of current knowledge on plant sources, traditional use, phytochemical composition, and preclinical and clinically proven effects, together with the Croatian translation of the corresponding monographs in the actual, 11th edition of the European Pharmacopoeia, is given for the aforementioned herbal drug in this thesis
Synthesis of new isoxazole and amidoxime purine bioisosteres with antitrypanosomal activity
No full textU ovom radu opisana je sinteza novog amidoksim-supstituiranog derivata benzotiazola 5 te novih hibrida benzimidazola i izoksazola 19a–e. Derivat 5 dobiven je višestupanjskom sintezom iz 4-aminobenzonitrila. Utvrđeno je da derivat 5 pokazuje antitripanosomsku aktivnost s IC50 vrijednosti od 0.92 μM, uz indeks selektivnosti 18. Zbog izražene biološke aktivnosti i visoke selektivnosti, derivat je korišten kao ligand za sintezu metalnih kompleksa renija(I) i mangana(I). N-propargilirani derivat benzimidazola 12 dobiven je reakcijom alkiliranja dok su odgovarajući oksimi 18a–e, potrebni za sintezu izoksazolnih derivata priređeni reakcijom kloriranja odgovarajućih aldoksima. Ciljani derivati 19a–e priređeni su bazno-kataliziranom 1,3-dipolarnom cikloadicijom iz N-propargiliranog derivata 12 i kloriranih oksima 18a–e. Strukture novosintetiziranih spojeva potvrđene su spektroskopijom 1H i 13C NMR. Naknadno će se provesti antitripanosomska ispitivanja ostalih novosintetiziranih spojeva.In this work, the synthesis of novel amidoxime derivatives of benzothiazole 5 and novel benzimidazole derivatives linked via an isoxazole spacer (19a–e) is described. Derivative 5 was obtained from 4-aminobenzothiazole by a multi-step synthesis. Derivative 5 was evaluated for its antitrypanosomal activity and gave an IC50 value of 0.92 μM against T. brucei, with a selectivity index of 18. Due to its significant biological activity and high selectivity, the derivative was used as a ligand for the synthesis of rhenium(I) and manganese(I) metal complexes. N-Propargylated benzimidazole derivative 12 was prepared by alkylation reaction. The corresponding oximes 18a–e for the synthesis of isoxazole derivatives were synthesized by the chlorination reaction of corresponding aldoximes.
The targer isoxazole derivatives 19a–e were prepared by base-catalyzed 1,3-dipolar cycloaddition of N-propargylated benzimidazole derivative 12 and chlorinated oximes 18a–e. The structures of all compounds were determined by 1H NMR and 13C NMR spectroscopy. Antitrypanosomal evaluations of these compounds will be performed
Aromatic profile of Ninski šokol : diploma thesis
No full textNinski šokol je jedinstveni gastronomski proizvod jedinstvene arome, koji ima dugu tradiciju proizvodnje u gradu Ninu i širem okolnom području. Za izradu ninskog šokola vrlo važno je kvalitetno svinjsko meso, ninska sol, razni začini i tradicijski proces proizvodnje. Specifičnosti sirovine, tehnološkog postupka pripreme i zrenja rezultiraju povećanjem koncentracije hlapljivih spojeva arome. Te su komponente proizašle iz biokemijskih procesa prilikom razgradnje masnog, vezivnog i mišićnog tkiva a odgovorne su za specifična okusna i mirisna obilježja ovog proizvoda. Hlapljivi spojevi su izolirani metodom mikroekstrakcije vršnih para na krutoj fazi (HS-SPME), korištenjem triju vlakana različite polarnosti. Izolirani spojevi su analizirani spregnutom tehnikom plinska kromatografija – spektrometrija masa (GC- MS) u cilju usporedbe sličnosti i razlika dobivenih rezultata. Ukupno je identificirano 38 spojeva koji se mogu svrstati u kemijske skupine: aldehide, alkohole, alkane, estere, fenole, masne kiseline i terpene.Ninski šokol is a distinctive gastronomic meat product with an unique aroma, produced for centuries in the town of Nin and its surrounding areas. Its preparation relies on high-quality pork, local salt from Nin, various spices and traditional methods, which are crucial for achieving its distinctive flavor. The specific qualities of the raw materials and the aging process lead to a higher concentration of volatile aromatic compounds. These compounds are result of biochemical processes that occur during the breakdown of fat, connective and muscle tissues, contributing to the unique taste and aroma of the product. The volatile compounds were isolated using headspace solid-phase microextraction (HS- SPME) with three fibers of different polarities. The extracted compounds were analyzed using gas chromatography-mass spectrometry (GC-MS) to compare the similarities and differences in the results. A total of 38 compounds were identified, categorized into the chemical groups such as aldehydes, alcohols, alkanes, esters, phenols, fatty acids, and terpenes, further highlighting the complexity and richness of Ninski šokol