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Solution-based synthesis of high-entropy oxide of transition metals
No full textCilj ovog rada bila je sinteza visoko-entropijskog oksida kemijske formule (TiZrHfNbTa)O11. Korištena su četiri postupka sinteze: limunski, koprecipitacijski, sol-gel i hidrotermalni. Kao polazni reaktanti za sve četiri sinteze korišteni su kloridi niobija (NbCl5), tantala (TaCl5), hafnija (HfCl4) i cirkonija (ZrCl4) te titanijev butoksid (Ti(C4H9O)). Svi sintetizirani uzorci karakterizirani su infracrvenom spektroskopijom s Fourierovom transformacijom (FTIR) te pretražnom elektronskom mikroskopijom i energijski razlučujućom rendgenskom spektroskopijom (SEM/EDXS). Na temelju SEM/EDXS rezultata zaključeno je da su kod svih sintetiziranih uzoraka udjeli niobija, tantala, hafnija i cirkonija približno jednaki dok je titanija gotovo dvostruko više, što je vjerojatno posljedica njegove veće reaktivnosti budući da se u reakcijsku smjesu uvodi u obliku alkoksida. Uzorci visoko-entropijskih oksida koji su u
SEM/EDXS analizama pokazali najveći stupanj homogenosti i dobro poklapanje množinskih udjela pojedinih elemenata s teorijskim udjelima, dodatno su analizirani rendgenskom difrakcijskom analizom (XRD). Na temelju XRD analize zaključeno je da se dobiveni difraktogrami žarenih visoko-entropijskih oksida podudaraju s literaturnim podacima čime je potvrđeno da su svi primijenjeni postupci prikladni za sintezu HEO ciljanog sastava. Iz difraktograma prekursora dobivenog hidrotermalnim postupkom zaključeno da tim postupkom sinteze nije moguće direktno dobiti oksid bez dodatnog koraka žarenja.The aim of this work was the synthesis of high-entropy oxide with the chemical formula (TiZrHfNbTa)O11. Four synthesis methods were used: citric, coprecipitation, sol-gel, and hydrothermal. Chlorides of niobium (NbCl5), tantalum (TaCl5), hafnium (HfCl4), and zirconium (ZrCl4), as well as titanium butoxide (Ti(C4H9O)), were used as starting reactants for all four syntheses. All synthesized samples were characterized using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDXS). Based on SEM/EDXS results, it was concluded that the contents of niobium, tantalum, hafnium, and zirconium in all synthesized samples are approximately equal, while the content of titanium is almost twice as high, likely due to its higher reactivity since it is introduced into the reaction mixture in the form of an alkoxide. High-entropy oxide samples that showed the highest degree of homogeneity in SEM/EDXS analyses and good matching of elemental molar ratios with theoretical values were further analyzed using X-ray diffraction analysis (XRD). Based on XRD analysis, it was concluded that the diffractograms of annealed high-entropy oxides match the literature data, confirming that all applied methods are suitable for the synthesis of HEO with the targeted composition. From the diffractogram of the precursor obtained by the hydrothermal method, it was concluded that this synthesis method does not directly yield an oxide without an additional annealing step
Novel 1,2,3-triazole derivatives of benzoxazole and benzimidazole: synthesis and structural characterization
No full textU ovom radu opisana je sinteza novih 1,2,3-triazolnih derivata benzoksazola i benzimidazola klik-reakcijom, njihova strukturna karakterizacija spektroskopijom NMR te analiza in silico. Reakcijom ciklokondenzacije odgovarajućih aminofenola pripravljeni su derivati benzo[d]oksazol-2-tiola 2 i 3 koji su reakcijom kondenzacije s 2-(klormetil)-1H-benzo[d]imidazolom 1 prevedeni u hibride benzimidazola i benzoksazola 4 i 5 premoštene tiometilenskom spojnicom. Reakcijom N-propargiliranja dobivenih hibrida pripravljeni su alkilirani derivati 7 i 8 koji su 1,3-dipolarnom cikloadicijom kataliziranom bakrom s prethodno pripravljenim azidima 9–16 prevedeni u ciljane 1,2,3-triazolne derivate benzimidazola i benzoksazola 18–31. Strukturna karakterizacija sintetiziranih spojeva provedena je spektroskopijom 1H- i 13C-NMR, dok su biološka djelovanja predviđena PASS analizom in silico.This paper describes the synthesis of novel 1,2,3-triazole derivatives of benzoxazole and benzimidazole by click reaction, their structural characterization using NMR spectroscopy and in silico analysis. Derivatives of benzo[d]oxazole-2-thiol 2 and 3 were prepared through cyclization of appropriate aminophenols, followed by condensation with 2-(chloromethyl)-1H-benzo[d]imidazole 1 to obtain hybrids of benzimidazole and benzoxazole 4 and 5 bridged by a thiomethylene linker. N-propargylation reaction of the resulting hybrids yielded alkylated derivatives 7 and 8, which underwent copper catalyzed 1,3-dipolar cycloaddition with prepared azides 9–16 to yield targeted 1,2,3-triazole derivatives of benzimidazole and benzoxazole 18–31. Structural characterization of novel compounds was carried out by 1H- and 13C-NMR spectroscopy, while biological activity was predicted by in silico PASS analysis
Validation of SPE-HPLC-MS/MS method for simultaneous analysis of palbociclib and fulvestrant in human plasma
No full textRak dojke najčešća je zloćudna bolest žena u razvijenom svijetu. Najčešći tip raka dojke je
HR+/HER2-. Razvoj rezistencije tumora na starije lijekove doveo je do potrebe za razvojem novih
lijekova, kao što su inhibitori kinaza ovisnih o ciklinima. Ovi lijekovi primjenjuju se uvijek u
kombinaciji s inhibitorima aromataze ili fulvestrantom. Bioanalitičkim metodama za terapijsko
praćenje lijekova u krvi omogućuje se precizno i individualno doziranje lijekova, potrebno zbog
razlika u farmakokinetici i uskoj terapijskoj širini lijeka. Sukladno ICHM10 smjernicama, u ovom
radu validirana je nova bioanalitička metoda za određivanje lijekova palbocikliba i fulvestranta,
izražavanjem linearnosti, točnosti, preciznosti, ekstrakcijskog prinosa i utjecaja matrice. Korištena
je tehnika ekstrakcije čvrstom fazom kojom su analiti izolirani iz plazme zdravih dobrovoljaca.
Analiza je provedena tekućinskom kromatografijom spregnutom sa spektrometrom masa s
analizatorom trostrukog kvadrupola. Metoda je validirana u koncentracijskim rasponima 30 - 300
ng/mL za palbociklib i 10 - 100 ng/mL za fulvestrant. Unutar koncentracijskih raspona dokazana je
linearnost (R > 0,9993) preciznost (RSD < 1,85) i točnost (raspon točnosti od -10,42 % do -3,92 %).
Ekstrakcijski prinos za palbociklib veći je od 91,17 %, dok je za fulvestrant veći od 77,52 %. Utjecaj
matrice za PAL je 10,25 % i 6,92 %, pri nižoj i višoj izmjerenoj koncentraciji, a za FUL iznosi -
11,99 % i -9,23 %. Naposlijetku su određene koncentracije palbocikliba i fulvestranta u uzorcima
plazme stvarnih pacijentica, čime je pokazana primjenjivost metode u terapijskom praćenju ovih
lijekova.Breast cancer is the most common malignant disease in women of the developed world. The most
common type of breast cancer is HR+/HER2-. The development of tumor resistance to older drugs
has led to the need to develop new ones, such as cyclin-dependent kinase inhibitors. These drugs are
always used in combination with aromatase inhibitors or fulvestrant. Bioanalytical methods for
therapeutic drug monitoring enable precise and individual drug dosing, necessary due to differences
in pharmacokinetics and a narrow therapeutic window of the drug. Following the ICHM10
guidelines, in this work a new bioanalytical method for detection of palbociclib and fulvestrant was
validated, expressing linearity, accuracy, precision, recovery and matrix effect. Solid-phase
extraction technique was used to isolate analytes from the plasma of healthy volunteers. The analysis
was performed by liquid chromatography coupled to a mass spectrometer with a triple quadrupole
analyzer. The method was validated in the concentration ranges of 30 - 300 ng/mL for palbociclib
and 10 - 100 ng/mL for fulvestrant. Linearity (R > 0.9993), precision (RSD < 1.85) and accuracy
(accuracy range from -10.42% to -3.92%) were demonstrated within the concentration range.
Recovery for palbociclib is greater than 91.17%, while for fulvestrant it is greater than 77.52%.
Matrix effect for PAL is 10.25% and 6.92%, at the lower and higher measured concentration, and
for FUL it is -11.99% and -9.23%. Finally, the concentrations of palbociclib and fulvestrant in
plasma samples of real patients were determined, which demonstrated the applicability of the
method in therapeutic drug monitoring
Porphyrins in photodynamic inactivation of Legionella in wastewater
No full textBakterija Legionella pneumophila često se nalazi u okolišu, u prirodnim i umjetno stvorenim vodenim sustavima, a može se pronaći i u komunalnim i otpadnim vodama. Ova bakterija, koja može uzrokovati ozbiljne komplikacije, poput po život opasne pneumonije, predstavlja fakultativni unutarstanični patogen. L. pneumophila ima sposobnost stvaranja biofilma, što joj omogućava otpornost na različita sredstva i metode dezinfekcije. Iz tog razloga potrebne su alternativne metode eliminacije ovog patogena, kao i dezinfekcije voda, njenih čestih staništa. Ovo istraživanje proučavalo je fotofizikalna svojstva i primjenu porfirinskih spojeva, TMPyP3 i Zn(II)-TMPyP3, kao fotosenzibilizatora. Strukturalna razlika Zn(II)-TMPyP3 u usporedbi s TMPyP3 potvrđena je UV-Vis spektrofotometrijom i ukazuje na različite fotofizikalne karakteristike ova dva spoja. Zn(II)-TMPyP3 je odabran kao fotosenzibilizator zbog prethodnih istraživanja provedenih na metaloporfirinskim kompleksima i utvrđenih antimikrobnih svojstava cinkovih kompleksa. Stabilnost ovih spojeva u otpadnoj vodi implicira izazove uzrokovane zamućenošću i prisutnošću tvari, sugerirajući potrebu za dodatnim istraživanjima. Rezultati mjerenja generiranja singletnog kisika pokazuju prednost TMPyP3 nad Zn(II)-TMPyP3, s većom učinkovitošću TMPyP3 pri nižim koncentracijama. TMPyP3 pokazuje poboljšanu fotodinamičku učinkovitost pri dužem izlaganju svjetlosti, što ga čini povoljnim za različite terapije. Ispitivanja antiadhezijskih svojstava potvrđuju veću djelotvornost TMPyP3, posebno u vodi iz slavine, naglašavajući njegov potencijal za prevenciju bakterijske adhezije. Sveukupno, ovo istraživanje potvrđuje veću djelotvornost TMPyP3 nad Zn(II)-TMPyP3 kao fotosenzibilizatora u ispitanim uvjetima, ističući važnost optimizacije uvjeta osvjetljavanja i potrebu za daljnjim istraživanjima u širem spektru valnih duljina radi poboljšanja učinkovitosti fotodinamičke terapije i njene primjene u stvarnim uvjetima, poput upotrebe u pročišćavanju otpadnih voda, odnosno njene dezinfekcije.The bacterium Legionella pneumophila is often found in the environment, in natural and man-made water systems, and can also be found in municipal and wastewater. This bacterium, which can cause serious complications such as life-threatening pneumonia, is a facultative intracellular pathogen. L. pneumophila has the ability to form biofilms, which enables it to resist various disinfection agents and methods. Therefore, alternative methods for eliminating this pathogen, as well as for disinfecting water, its frequent habitat, are needed. This study examined the photophysical properties and application of porphyrin compounds, TMPyP3 and Zn(II)-TMPyP3, as photosensitizers. Structural change in Zn(II)-TMPyP3 compared to TMPyP3 was confirmed by UV-Vis spectrophotometry and indicated different photophysical characteristics. Zn(II)-TMPyP3 was chosen as photosensitizer due to previous research conducted on metalloporphyrin complexes, which identified antimicrobial properties of zinc(II) complexes. The stability of these compounds in wastewater implies challenges caused by turbidity and the presence of substances, suggesting the need for further research. Results of singlet oxygen generation studies show the advantage of TMPyP3 over Zn(II)-TMPyP3, with TMPyP3 being more efficient at lower concentrations. TMPyP3 shows improved efficiency with prolonged light exposure, making it favorable for various therapies. Tests on anti-adhesion properties confirm the greater effectiveness of TMPyP3, especially in tap water, highlighting its potential for preventing bacterial adhesion. Overall, this research confirms the higher efficency of TMPyP3 over Zn(II)-TMPyP3 as a photosensitizer in tested conditions, emphasizing the importance of optimizing irradiation conditions and the need for further research across a broader spectrum of wavelengths and other photosensitizers to improve the effectiveness of photodynamic therapy and its application in real-world conditions, such as wastewater purification and disinfection
Influence of AC MIG process parameters on residual stress in wire and arc additive manufacturing
No full textOvaj diplomski rad analizira proces aditivne proizvodnje pomoću tehnologije električnog luka i žice (WAAM) s fokusom na zavarivanje aluminijskih legura korištenjem AC MIG postupka. Aditivna proizvodnja, poznata i kao 3D printanje, omogućuje izradu složenih geometrijskih oblika dodavanjem materijala sloj po sloj. U radu je posebna pažnja posvećena utjecaju ključnih parametara zavarivanja na zaostala naprezanja u aluminijskim legurama serije 6xxx, koja se ispituju metodom rendgenske difrakcije (XRD). Eksperimentalni dio uključuje analizu različitih konfiguracija parametara zavarivanja, kao što su omjer EN polariteta, frekvencija, i dodavanje helija, kako bi se optimizirala kvaliteta zavarenih spojeva. Rezultati istraživanja doprinose razumijevanju formiranja zaostalih naprezanja i poboljšanju procesa aditivne proizvodnje u industrijama kao što su zrakoplovna i automobilska.This thesis analyses the additive manufacturing process using Wire Arc Additive Manufacturing (WAAM) technology, with a focus on welding aluminium alloys through the AC Metal Inert Gas (AC MIG) process. Additive manufacturing, also known as 3D printing, enables the production of complex geometric shapes by adding material layer by layer. The study pays special attention to the influence of key welding parameters on residual stresses in 6xxx series aluminium alloys, examined using the X-Ray Diffraction (XRD) method. The experimental part includes the analysis of various welding parameter configurations, such as the EN polarity ratio, frequency, and helium addition, to optimize the quality of weld joints. The research results contribute to the understanding of residual stress formation and the improvement of the additive manufacturing process in industries such as aerospace and automotive
Influence of matrix composition on photolytic and photcatalytic degradation of N-nitrosamines
No full textU procesu dezinfekcije vode mogu nastati dezinfekcijski nusprodukti (DNP) koji su štetni za ljudsko zdravlje. Primjer dezinfekcijskih nusprodukata su nitrozamini koji sadrže dušik te doprinose toksičnosti vode. Zbog toga je neophodno razviti učinkovite metode uklanjanja DNP-a iz vode, kao što su napredni oksidacijski i membranski procesi. U ovom radu istražena je fotolitička i fotokatalitička razgradnja N-nitrozamina korištenjem UV-LED fotoreaktora. Analizirani N-nitrozamini su: N-nitrozo-dimetilamin (NDMA), N-nitrozodietilamin (NDEA),
N-nitrozomorfolin (NMOR) i N-nitrozopiperidin (NPIP). Za izvor zračenja korištene su
UV-A (λ = 365 nm) i UV-C (λ = 272 nm) svjetleće diode. Fotokatalitička razgradnja nitrozamina izvedena je pomoću tankog filma TiO2 te uz pomoć suspenzije TiO2. Fotolitička razgradnja ispitana je u ultračistoj, sintetskoj bazenskoj, morskoj i boćatoj vodi te u retentatu nakon
RO/NF postupka. Istražen je utjecaj valne duljine zračenja, broja LED dioda te sastava matrice na kinetiku razgradnje N-nitrozamina. Rezultati su pokazali da je najučinkovitiji fotoreaktor s najvećim brojem UV-A LED dioda za sve ispitane matrikse tijekom perioda od 60 min.Disinfection by-products (DBP) are harmful to human health and are formed during water disinfection. Examples of disinfection by-products are nitrosamines that contain nitrogen and contribute to the toxicity of drinking water. Therefore, it is necessary to develop effective methods for removing DBPs from water, such as advanced oxidation and membrane processes. In this paper, the photolytic and photocatalytic degradation of N-nitrosamines was investigated using a UV-LED photoreactor. The analyzed N-nitrosamines are:
N-nitroso-dimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosomorpholine (NMOR), and N-nitrosopiperidine (NPIP). UV-A (λ = 365 nm) and UV-C (λ = 272 nm)
light-emitting diodes were used as the radiation source. The photocatalytic degradation of nitrosamines was carried out using a thin film of TiO2 and with the help of a TiO2 suspension. The photolytic degradation was carried out in ultrapure, synthetic pool, sea, and brackish water and in retentate after the RO/NF process. The influence of the radiation wavelength,
the number of LEDs and the type of matrix on the kinetics of N-nitrosamine degradation were investigated. The results showed that the most efficient photoreactor is that with UV-A LED diodes with six columns of UV-LED strips in all tested matrices during a time period of 60 min
Determining the minimum of quality of life: Case study of Krapina-Zagorje County
No full textOvaj rad problematizira kvalitetu života u Krapinsko-zagorskoj županiji. Hijerarhijskom klaster analizom naselja Županije grupirana su u šest klastera (tipova) naselja prema broju i dostupnosti usluga od općeg interesa. Kako bi se identificirale potrebe stanovništva, korištena je mješovita metodologija, koja podrazumijeva primjenu kvalitativnih i kvantitativnih metoda, odnosno fokusnih skupina i anketnog istraživanja. Iako minimum kvalitete života predstavlja nešto elementarno i nužno za život, aspekti koji ga čine variraju ovisno o klasteru stanovanja i potrebama stanovništva. Kvalitetom života u Krapinsko-zagorskoj županiji ispitanici su generalno zadovoljni; ona uglavnom koincidira s brojem i dostupnošću usluga od općeg interesa – što je naselje opremljenije uslugama, to je kvaliteta života veća. Ipak, uočena je iznimka u smanjenom zadovoljstvu u onim klasterima koji su opremljeniji uslugama, a u bliskoj prošlostisu zabilježili pad broja usluga od općeg interesa. Usluge od općeg interesa imaju snažan kohezivni učinak – one okupljaju stanovništvo i doprinose zajednici, dok njihovo gašenje utječe na (sve manju) socijalizaciju te gubitak osjećaja mjesta i zajedništva. Najveće prednosti života u Županiji predstavljaju sigurnost naselja, odnosno mogućnost neometanog kretanja javnim prostorom te blizina prirode kao mjesta provođenja slobodnog vremena. S druge strane, kao najveći nedostatak ističe se loša povezanost javnim prijevozom, koji igra važnu ulogu u dostupnosti usluga nužnih za svakodnevno funkcioniranje kod onih koji nemaju pristup osobnom automobilu.This paper examines the quality of life in Krapina-Zagorje County. Using hierarchical cluster analysis, the County’s settlements were grouped into six clusters (types) based on the number and accessibility of services of general interest. In order to identify the population's needs, a mixed-methods approach was applied, combining qualitative and quantitative methods, specifically focus groups and surveys. While the minimum of quality of life represents something fundamental and necessary for living, the aspects that constitute it vary depending on the cluster and the needs of the population. Respondents are generally satisfied with the quality of life in Krapina-Zagorje County, which largely coincides with the number and availability of services of general interest— the better a settlement is equipped with services, the higher the quality of life. However, an exception was observed in clusters that are well-equipped with services but have experienced a decline in the number of services of general interest in recent years, leading to decreased satisfaction. Services of general interest have a strong cohesive effect – they contribute to the community, while their ceasing negatively impacts socialization and leads to a loss of sense of place and belonging. Key advantages of Krapina-Zagorje County include the safety of its settlements, which allows for free movement in public spaces, as well as its proximity to nature, regarded as a recreational space. On the other hand, the most significant drawback is the lack of efficient public transport services, which are crucial for accessing essential services, particularly for those without access to private vehicles
Reliability analysis and improvement of a device for non-destructive testing of reactor pressure vessel welds
No full textKoncepti pouzdanosti i analize pouzdanosti sve više dobivaju na važnosti povećanjem složenosti proizvoda i porastom zahtjeva krajnjih korisnika. To je posebice izraženo u postrojenjima visokih rizika, poput nuklearnih elektrana, gdje je pouzdanost ključan aspekt u očuvanju integriteta postrojenja, ali i sprječavanja dugotrajnog zastoja rada elektrane do kojeg može doći uslijed kvarova uređaja kojima se vrši inspekcija pojedinih dijelova postrojenja. Upravo iz tog razloga cilj ovoga rada bio je provesti analizu pouzdanosti uređaja za ispitivanje zavara tlačnih posuda reaktora i predložiti konstrukcijske promjene kojima će se povećati pouzdanost komponenti i podsustava kod kojih postoji povećani rizik od kvara.
Radi upoznavanja s problematikom inženjerstva pouzdanosti, najprije su definirani pojmovi poput kvara, rizika, pouzdanosti i raspoloživosti sustava, te je definirana metodologija provedbe analize pouzdanosti. U metodologiji je poseban naglasak stavljen na ispravnu i temeljitu provedbu funkcijske analize, kao i na odabir i primjenu različitih metoda za analizu pouzdanosti. Kako bi se za konkretni slučaj omogućio odabir najprimjerenije metode, te postigli bolji rezultati i točnija primjena metode, prvo je dan pregled njihovih karakteristika, prednosti i nedostataka. U sljedećem koraku je provedena FMEA analiza, kao odabrana metoda za analizu pouzdanosti, na spomenutom uređaju za inspekciju zavara posude reaktora, kojeg razvija tvrtka INETEC. Najprije su opisani sam uređaj, njegov princip rada i interakcija s drugim podsustavima, nakon čega su provedbom funkcijske analize identificirane glavne i pomoćne funkcije uređaja, kao osnova za izradu FMEA tablica u kojima su potom definirani svi mogući načini, uzroci i posljedice otkazivanja. Pri njihovom definiranju, kao i kvantifikaciji ozbiljnosti i učestalosti, pomoglo je prijašnje iskustvo tvrtke te podaci od dobavljača i proizvođača. FMEA analizom identificirano je 1067 malih i srednjih rizika, 141 visokih te 29 kritičnih rizika u sustavu. Visoki rizici su u najvećoj mjeri posljedica prekida tokova zraka i energije kroz sustav, kao i mogućeg prodiranja vode unutar uređaja. Kvarovi, odnosno greške koje mogu nastati u sustavu najčešće su rezultat neadekvatne ulazne kontrole dijelova, pogrešnog proračuna, neadekvatne konstrukcije, kao i grešaka na softveru, instrumentu, kontrolnoj kutiji ili uslijed rukovanja operatera. Za sve rizike predložene su mjere za njihovo smanjenje, dok su za one kritične napravljene odgovarajuće konstrukcijske promjene, pri čemu su se najkritičnijim pokazali podsustavi za vakuumsko prianjanje uređaja za stijenku posude. Na samom kraju dan je kritički osvrt na upotrebu navedenih metoda te su dani prijedlozi za budući rad.Reliability and reliability analysis concepts are increasingly gaining importance with the increase in product complexity and end-user requirements. This is particularly noticeable in high-risk facilities, such as nuclear power plants, where reliability is a crucial aspect not only in preserving the plant's integrity but also preventing the prolongation of the outage phase of power plants that can occur due to in-service inspection device failures during the inspection of the plant parts. For this reason, aim of this paper was to analyze the reliability of a device for ultrasonic testing of reactor pressure vessel welds and propose required design changes that will increase the reliability of components and subsystems where an increased risk of failure has been identified. In order to get acquainted with the issue of reliability engineering, terms such as failure, risk, reliability, availability, maintainability, and quality were addressed, after which the methodology for conducting reliability analysis was defined. Within the methodology, great emphasis was placed on the correct and thorough implementation of functional analysis and the selection and application of different methods for reliability analysis. An overview of the characteristics, advantages, and disadvantages of each of the methods is given in order to select the most appropriate methods for the respective case and to ensure correct application and better results. In the next step, an FMEA analysis was performed on said in-service inspection device, currently being developed by the INETEC company. First, the device itself, its principle of operation and interaction with other subsystems were described, after which the main and auxiliary functions of the device were collected through the functional decomposition process. Based on the decomposition, the FMEA table was created in which all failure modes, causes and effects for said functions are defined. In defining them, as well as quantifying their severity and occurrence, the company's previous experience and data from suppliers and manufacturers helped. FMEA analysis identified 1067 minor and medium risks, 141 high and 29 critical risks in the system. The high risks are largely due to the interruption of air and energy flows through the system, as well as the possible penetration of water inside the device. Malfunctions and errors that can occur in the system, are most often the result of inadequate input control of parts, incorrect calculation, inadequate construction, as well as errors in software, instrument, control box or due to operator handling. For all risks, suggestions for their mitigation have been proposed, while for those critical, appropriate design changes have been made. At the very end, a critical review of the use of these methods is given as well as future work suggestions
Proces učenja nogometne igre kod djece predškolske dobi
No full textDijete u ranom djetinjstvu kroz pokret istražuje svijet oko sebe, stoga je potrebno već u toj dobi razvijati morfološke, motoričke i funkcionalne sposobnosti. U ranom djetinjstvu počinje interes djeteta za sport. Među djecom predškolske dobi najpopularniji sport je nogomet, te se sve više djece uključuje u škole nogometa već s 5 godina. Cilj ovog rada bio je ponuditi program škole nogometa s djeci primjerenim sadržajima i istražiti utjecaj tog programa na motorička dostignuća djece predškolske dobi. Uzorak ispitanika činilo je 33 djece u dobi od 4 do 6 godina, (23 djece u kontrolnoj skupini i 10 djece u eksperimentalnoj skupini). Od toga je bilo 26 dječaka i 7 djevojčica. Uzorak varijabli činila su tri testa za procjenu antropometrijskih (morfoloških) karakteristika, šest testova za procjenu motoričkih sposobnosti, jedan test za procjenu funkcionalnih sposobnosti, a nogometnim poligonom procjenjivala su se motorička dostignuća djece. Rezultati su pokazali statistički značajnu razliku u 2 motoričke varijable (varijabli poligon 3 i varijabli zgib) između djece eksperimentalne i kontrolne skupine u korist djece iz eksperimentalne skupine. Ovaj rezultat djelomično potvrđuje hipotezu kako će se utvrditi statistički značajne razlike u motoričkim postignućima i antropološkim obilježjima između eksperimentalne i kontrolne skupine.In early childhood a child is exploring the world around him. Because of that, it is necessary to develop morphological, motor and functional skills during that period. Interests in sports begins in early childhood. In preschool age football is the most popular sport, and most children are choosing football at age of 5. Goal of this study was to offer an educational program for football school with an appropriate agenda, monitor and explore that program on motor abilities of preschool children. In this program participate 33 children aged 4 to 6, 23 were in the control group and 10 in the experimental group. Pattern of variables consisted of three tests to assess Anthropometric (morphological) characteristics, six tests to assess motor skills, one test to asses functional skills, and a football polygon was used to asses the motor achievements of children. The results shows statistically significant differences in 2 motorical variables (polygon 3 and joint) between the children of the experimental group and control groups in favor of the children from the experimental groups. This result partially confirms the hypothesis that it will be shown statistically significant differences in motorical skills performance and anthropological characteristic between the experimental and control groups
Bridge carrier for telescopic winch crane
No full textU ovom radu bit će prikazan proračun, konstrukcijska izvedba i odabir komponenti mosnog granika. Mosni granik će se koristit za rukovanje, pregled i održavanje komoraza ispitivanje te će bit konstruiran u skladu s zahtjevima. Glavni nosač će bit izveden pomoću kutijastih profila, dok će pomoćni nosač biti izveden pomoću HEB profila. U ovome radu će još biti i prikazan proračun pomoćnog vitla.In this paper calculation, design and selection of bridge crane components will be presented. The bridge crane will be used for handling, inspection and maintenance of the test chamber and will be constructed in accordance with the requirements. The main bridge will be constructed using box profiles while the auxiliary bridge will be constructed using HEB profile. Calculation of the auxiliary winch will also be presented in this paper