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Investigation of the influence of iron in cultivated bean sprouts of Lepidium sativum L. on the content of metals determinated by atomic absorption spectroscopy and the profile of glucosinolates quantified by high performance liquid chromatography : master thesis
No full textBiljka Lepidium sativum L. je jednogodišnja kultura koja se na zapadu često koristi u ljudskoj prehrani radi dobrih svojstava, izdržljivosti i lakog uzgoja. U ovom radu je prikazan uzgoj klica biljke Lepidium sativum L. na vodenim otopinama željeza različitih koncentracija te je praćen njihov razvoj tijekom dva tjedna, a zatim je prikazana metoda pripreme biljnog materijala za analizu atomskim apsorpcijskim spektrometrom. Koristeći se navedenom tehnikom, određena je koncentracija željeza u klicama. Uočen je porast koncentracije željeza u uzgajanim klicama, u skladu s povećanjem koncentracije željeza u vodenim otopinama na kojima su biljke uzgajane. U ovome radu izolirani su glukozinolati iz sjemena uzgojenih klica Lepidium sativum L. metodom ekstrakcije 70 %-tnim metanolom uz desulfataciju enzimom sulfataza te određeni UHPLC-DAD-MS/MS tehnikom. U uzorku klica obogaćenih vodenom otopinom željeza od 1 ppm u odnosu na referentni uzorak uočava se pad koncentracije glukotropeolina i povećanje 4-metoksiglukobrasicina. Nadalje, kod klica koje su uzgajane na vodenim otopinama željeza koncentracije 5 ppm i 10 ppm uočen je pad glukotropeolina kao i pad koncentracije 4-metoksiglukobrasicina. Kod klica uzgajanim na vodenoj otopini željeza koncentracije 25 ppm uočen je pad koncentracije glukotropeolina u odnosu na referentni uzorak kao i povećanje koncentracije 4-metoksiglukobrasicina.The plant Lepidium sativum L. is an annual crop that is often used in the human diet in the West for its good properties, durability and ease of cultivation. In this paper, the cultivation of Lepidium sativum L. bean sprouts on aqueous solutions of iron of different concentrations is presented and their development is monitored for two weeks. The method of preparation of plant material for analysis by atomic absorption spectrometer is presented. Using the above mentioned technique the concentration of iron in the bean sprouts was determined. An increase in the concentration of iron in the grown bean sprouts was observed, in line with the increase in the concentration of iron in the aqueous solutions on which the plants were grown. In this work, glucosinolates were isolated from the seeds of cultivated bean sprouts of Lepidium sativum L. by the method of extraction with 70% methanol with desulfation with the enzyme sulfatase and determined by UHPLC-DAD-MS / MS technique. In a sample of bean sprouts grown on an aqueous solution of iron of 1 ppm compared to the reference sample, a decrease in the concentration of glucotropeolin and an increase in 4-methoxyglucobrasicin was observed. Furthermore, in bean sprouts grown on aqueous iron solutions with concentrations of 5 ppm and 10 ppm, a decrease in glucotropeolin as well as a decrease in the concentration of 4- methoxyglucobrasicin was observed. In bean sprouts grown on aqueous iron solution with a concentration of 25 ppm, a decrease in the concentration of glucotropeolin compared to the reference sample was observed, as well as an increase in the concentration of 4-methoxyglucobrasicin
Corrosion inhibitition of coper by Padina pavonica (Linnaeus) Thivy extract : diploma thesis
No full textU ovom radu ispitano je djelovanje 75 %-tnog etanolno - vodenog eksrakta smeđe alge Padina pavonica (u volumenskim koncentracijama 0,2 % , 0,8 %, 1,4 % i 2,0 % ) kao inhibitora korozije bakra u 0,5 mol dm -3 otopini NaCl. Pri istraživanju su korištene elektrokemijske metode: potencijal otvorenog kruga, metoda linearne polarizacije i metoda potenciodinamičke polarizacije. Nakon provedenih polarizacijskih mjerenja napravljena je analiza površine uzoraka pretražnim elektronskim mikroskopom čime su potvrđeni rezultati dobiveni elektrokemijskim mjerenjima. Za najbolju volumensku koncentraciju inhibitora, 1,4 % (koja je određena u ovom radu) ispitana je korozija u temperaturnom području od 273 do 303 K. Korištenjem adsorpcijskih izotermi (Freundlichove i Frumkinove) određen je mehanizam adsorpcije inhibitora na površinu bakra, tj. rezultati potvrđuju da se radi o fizisorpciji.This paper aims to study the inhibition effect of aqueous ethanol 75 % extract of brown algae Padina pavonica (in 0.2 %, 0.8 %, 1.4 % and 2.0 % (v/v) concentration) on corrosion of copper in the 0.5 mol dm –3 NaCl solution by electrochemical techniques such as open circuit potential, linear polarization, and potentiodynamic polarization technique. Additionally, a characterization of the metal surface with scanning electron microscope (SEM). The data demonstrated that the highest protection was obtained at the algae extract concentration of 1.4 % v/v. The SEM analysis gave very good support to the electrochemical data. Also, the temperature influence was studied in the range 283 – 303 K. The adsorption of Padina Pavonica on copper surface was in accordance with the Freundlich and Frumkin adsorption isotherms. Results confirm physical adsorption of this inhibitor on the copper
The equilibrium of copper adsorption on untreated humus Potgrond H(T=298 K : bachelor thesis
No full textIspitana je adsorpcija bakrovih iona na netretiranom humusu u ovisnosti o različitim početnim koncentracijama otopina bakrovih iona (2,876 mmol dm-3, 5,415 mmol dm-3, 8,200 mmol dm-3, 11,091 mmol dm-3 te 14,524 mmol dm-3). Eksperiment je proveden pri stalnoj temperaturi od 298 K, brzini miješanja od 200 okr min-1, u trajanju od 48 h na netretiranom humusu. Koncentracije bakrovih iona prije i nakon adsorpcije su određene spektrofotometrijski. Na temelju dobivenih rezultata može se zaključiti kako se količina adsorbiranih bakrovih iona (qe) neznatno mijenja s porastom početne koncentracije bakrovih iona u otopini (c0), a svoju maksimalnu vrijednost dostiže pri početnoj koncentraciji od 8,200 mmol dm-3 te iznosi qe = 0,272 mmol g-1 za uvjete pri kojima je eksperiment proveden. Učinkovitost adsorpcije bakrovih iona dostiže svoju maksimalnu vrijednost za najnižu odabranu početnu koncentraciju od 2,876 mmol dm-3 te iznosi 46,990 % te nakon toga opada s porastom početne koncentracije bakrovih iona u otopini. Adsorpcija bakra na netretiranom humusu može se opisati Langmuirovim adsorpcijskim modelom (R2 = 0,999).Ispitana je adsorpcija bakrovih iona na netretiranom humusu u ovisnosti o različitim početnim koncentracijama otopina bakrovih iona (2,876 mmol dm-3, 5,415 mmol dm-3, 8,200 mmol dm-3, 11,091 mmol dm-3 te 14,524 mmol dm-3). Eksperiment je proveden pri stalnoj temperaturi od 298 K, brzini miješanja od 200 okr min-1, u trajanju od 48 h na netretiranom humusu. Koncentracije bakrovih iona prije i nakon adsorpcije su određene spektrofotometrijski. Na temelju dobivenih rezultata može se zaključiti kako se količina adsorbiranih bakrovih iona (qe) neznatno mijenja s porastom početne koncentracije bakrovih iona u otopini (c0), a svoju maksimalnu vrijednost dostiže pri početnoj koncentraciji od 8,200 mmol dm-3 te iznosi qe = 0,272 mmol g-1 za uvjete pri kojima je eksperiment proveden. Učinkovitost adsorpcije bakrovih iona dostiže svoju maksimalnu vrijednost za najnižu odabranu početnu koncentraciju od 2,876 mmol dm-3 te iznosi 46,990 % te nakon toga opada s porastom početne koncentracije bakrovih iona u otopini. Adsorpcija bakra na netretiranom humusu može se opisati Langmuirovim adsorpcijskim modelom (R2 = 0,999)
Innovative methods of isolation of bioactive compounds from plant material using eutectic solvents : bachelor thesis
No full textCilj ovog rada bilo je istražiti eutektička otapala (DES), te njihovu primjenu u izolaciji bioaktivnih spojeva iz biljnog materijala. Eutektička otapala zbog svojih svojstava i lakoće pripreme sve više zamjenjuju organska otapala u industriji. Nastaju miješanjem dvaju ili više prirodnih organskih komponenata, kao što su kolin klorid, karboksilne kiseline, urea, glicerol i drugi. Važan je odabir komponenata prilikom pripreme kako bi se dobila smjesa željenih svojstva, poput viskoznosti, gustoće, električne vodljivosti, itd. Postoje razne metode pripreme DES-ova, a najčešća upotrjebljena metoda je zagrijavanje dviju čvrstih komponenata na određenoj temperaturi sve dok se ne dobije bistra otopina. Pretraživanjem dostupne literature i dosadašnjih istraživanja o eutektičnim otapalima, moguće je zaključiti da će primjena eutektičnih otapala bit sve veća.The aim of this study was to investigate deep eutectic solvents (DES) and their application in isolation of bioactive compounds from plant material. Due to their properties and easy preparation, eutectic solvents are increasingly replacing organic solvents in industry. They are formed by mixing two or more natural organic components, such as choline chloride, carboxylic acids, urea, glycerol and others. It is important to select the components during preparation to obtain a mixture of desired properties, such as viscosity, density, electrical conductivity, etc. There are various methods of preparing DESs, and the most common method used is heating two solid components at a certain temperature until clear solution is formed. By searching the available literature and previous research on eutectic solvents, it is possible to conclude that the use of eutectic solvents will be increasing
Testing of response of the ion-selective membranes made of FeS, Ag2S and PTFE on ferrous and ferric ions : bachelor thesis
No full textProvedeno je testiranje odziva ion-selektivnih membrana na željezove(III) i željezove(II) katione pri pH=1, pH=1,5 i pH=4. U radu je opisana priprava otopina korištenih u radu te samo ispitivanje membrana u određenim otopinama. Izvedba samog eksperimenta odvijala se pomoću potenciometrijske metode koju odlikuju visoka isplativost i jednostavnost. Relativno dobre rezultate elektrode su pokazale na željezove(III) katione, dok za željezove(II) katione mjerenje nije bilo moguće provesti. Promjenom koncentracije i pH ispitivala se selektivnost same metode. Mjerenja su se provodila do trenutka kada razlika između dva mjerenja nije iznosila 1 mV.The response of ion-selective membranes to iron(III) and iron(II) cations at pH = 1, pH = 1.5 and pH = 4 was tested. This thesis describes the preparation of solutions used in the work and testing of membranes in certain solutions. The experiment itself was performed using the potentiometric method which is characterized as cost- effective and simplicity. Relatively good electrode results were shown for iron(III) cations, while for iron(II) cations the measurement could not be performed. The selectivity of the method itself was examined by changing the concentration and pH. Measurements were performed until the difference between the two measurements was 1mV
Profile of volatile compounds of mandarin peels Zorica variety : bachelor thesis
No full textU ovom radu analiziran je kemijski sastav hlapljivih spojeva svježe i suhe kore mandarine sa OPG- a Marijana Sršljena. Hlapljivi spojevi izolirani su metodom mikroekstrakcije vršnih para na krutoj fazi (HS- SPME) uz pomoć plavog vlakna (PDMS/DVB). Dobiveni uzorci analizirani su vezanom tehnikom plinska kromatografija-spektrometrija masa (GC-MS). HS-SPME/GC-MS metodom identificiran je 21 spoj u svježoj kori mandarine, dok je u suhoj kori identificirano 19 spojeva. Identificirani spojevi mogu se većinski svrstati u skupinu terpena, a razlika njihovih udjela u svježoj i suhoj kori je u promilima.In this paper is analyzed the chemical composition of volatile compounds of fresh and dried mandarin peel from the Marijan Sršljen family farm. Volatile compounds were isolated by the headspace- solid phase microextraction method (HS-SPME) using blue fiber (PDMS / DVB). The obtained samples were analyzed by the gas chromatography-mass spectrometry (GC-MS) technique. The HS-SPME/GC-MS method identified 21 compounds in fresh mandarin peel, while 19 compounds were identified in dry peel. The identified compounds can be mostly classified into the group of terpenes, and the difference between their proportions in fresh and dry bark differs is in per mille
Procedure for obtaining nodular cast iron and making dry mooring for tankers : bachelor thesis
No full textU ovom završnom radu objašnjen je postupak dobivanja nodularnog lijeva te izrada suhog veza. Rad je sastavljen od teorijskog i praktičnog dijela. U teorijskom dijelu objašnjena su svojstva nodularnog lijeva, njegove prednosti i nedostaci u odnosu na ostale željezne ljevove kao što su sivi i vermikularni te utjecaj različitih elemenata na mikrostrukturu i svojstva nodularnog lijeva, te su prikazani postupci dobivanja nodularnog lijeva. U praktičnom dijelu prikazan je postupak proizvodnje nodularnog lijeva u ljevaonici Brodograđevne industrije Split koji se sastoji od izrade posebnih kalupa, lijevanja čelika u posebne kalupe za oblikovanje suhog veza te naknadnog ispitivanja mehaničkih svojstava epruveta nodularnog lijeva.In this thesis, the ductile iron production process and making a dry bond is explained in detail. The thesis consists of theoretical and practical part. In the theoretical part explanation about the properties of ductile iron, its advantages and disadvantages compared to other iron castings such as gray and vermicular, and the influence of different elements on the microstructure and properties of ductile iron are given and also methods of obtaining ductile iron are described. In the practical part detail discussion about the process of ductile iron production in the Brodosplit foundry, which consists of making special molds, casting steel into special molds to form a dry bond, are given along with the subsequent testing of the mechanical properties of ductile iron test tubes
Rocket (Eruca vesicaria (L.) Cav.) as a potential copper hyperaccumulator
No full textU ovom diplomskom radu ispitan je utjecaj zalijevanja rukole (Eruca vesicaria (L.) Cav.) otopinom teškog metala (bakra), kao i utjecaj raznih dodataka humusu na sposobnost hiperakumulacije bakra u rukoli. Vizualnom karakterizacijom rukole uočeno je kako rukola, neovisno u kojem humusu je uzgajana ili s čime je zalijevana, nije pokazala vidljive znakove fitotoksičnosti. Naprotiv, rukola zalijevana vodenom otopinom CuSO4∙5H2O je imala tamnije listove tokom čitavog perioda zalijevanja te je nakon četrdeset dana imala najmanje suhih listova. Najviša koncentracija bakra u organima rukole izmjerena je u uzorcima biljke koja je zalijevana otopinom teškog metala CuSO4∙5H2O (624,32 μg g-1), dok je najniža koncentracija izmjerena u uzorku rukole koja je zalijevana vodovodnom vodom, a uzgajana u humusu s dodatkom humusa na koji je prethodno vezan bakar (70,86 µg g-1). S obzirom da je rukola u periodu od četrdeset dana zalijevanja vodenom otopinom bakra usvojila visoku koncentraciju bakra u svojim organima (624,32 µg g-1) bez vidljivih znakova fitotoksičnosti može se zaključiti kako se radi o hipertolerantnoj biljci u odnosu na bakar kao teški metal. Daljnjim istraživanjima rukola bi se trebala duže tretirati vodenom otopinom bakra kako bi se mogla dokazati hiperakumulacija bakra kao teškog metala u rukoli, odnosno ispitati utjecaj bakra na njen rast i razvoj.In this diploma thesis, the influence of rocket (Eruca vesicaria (L.) Cav.) watering with heavy metal (copper) solution, as well as the influence of various humus additives to the ability of copper hyperaccumulation in the rocket was examined. It was noticed that the rocket, independently of in which humus the plant was growing or with what it was watered, did not show any visible signs of phytotoxicity. On the contrary, the rocket watered with the aqueous solution of CuSO4∙5H2O had darker leaves during the whole period of treatment and had the smallest amount of dry leaves after forty days of cultivation. The highest concentration of copper in the rocket was measured in the samples of the plant that was watered with a solution of heavy metal CuSO4∙5H2O (624.32 μg g-1), while the lowest concentration was measured in the sample of the rocket which was watered with water and grown in humus with the addition of humus on which the copper was previously sorbed (70.86 µg g-1). Given that the rocket in a forty-day period of watering with an aqueous copper solution has taken up a high concentration of copper in its organs (624.32 μg g-1) with no visible signs of phytotoxicity it can be concluded that it is a hypertolerant plant for copper as a heavy metal. In further investigations the rocket should be treated longer with aqueous copper solution to prove the hyperaccumulation of copper as a heavy metal in the rocket, as well as to investigate its influence on the growing and development of the rocket
Effect of PBT impeller position on ion exchange : diploma thesis
No full textOvaj rad predstavlja dio istraživanja koja se odnose na analizu utjecaja parametara miješanja na ionsku izmjenu. U ovom radu sagledan je utjecaj pozicije turbinskog miješala s ravnim lopaticama nagnutim pod kutem od 45⁰ (tzv. PBT miješalo) na ionsku izmjenu bakra na sintetskom zeolitu NaXu neprotočnom kotlastom reaktoru. Ispitao se utjecaj pozicije PBT miješala na suspendiranje čestica zeolita NaX i utrošak snage miješanja kod stanja potpune suspenzije. Omjer udaljenosti miješala od dna posude (C) i visine stupca kapljevine (H) u različitim eksperimentima je iznosio 0.10, 0.33 i 0.50. Ispitao se i utjecaj pozicije miješala na kinetiku ionske izmjene pri stanju potpune suspenzije. Eksperiment su provedeni pri stalnoj temperaturi od 300 K u suspenziji volumena od 2.14 dm 3 u kojoj krutu fazu predstavlja 10.5 g zeolita NaX veličine čestica 0.063-0.09 mm, a kapljevitu otopina bakrovog (II) nitrata. Iz dobivenih kinetičkih podataka uočava se kako je proces izmjene iona brz u početnom periodu nakon čega usporava do uspostave ravnoteže. Kinetička analiza dobivenih eksperimentalnih podataka provedena je korištenjem dva kinetička modela Ritchievog i Morris-Weberovog modela. Dobiveni rezultati pokazali su dobro slaganje eksperimentalnih podataka s Ritchiev-im modelom.This work presents a part of systematic researches which are related to analysis of the influence of mixing parameters on ion exchange. Focus pf this research was on the influence of diameter of pitched blade turbine (abbrev PBT impeller) on copper exchange on synthetic zeolite NaX in a batch reactor. Influence of PBT impeller position on suspended zeolite particles NaX and mixing power to achieve the complete suspension state was explored. Ratio C/H is the impeller off-bottom clearance (C) to liquid height ratio (H), with the values of C/H= 0.10, 0.33, 0.50. The effect of impeller position was explored on the kinetic of ion exchange at complete suspension. Study was conducted at the constant temperature (300 K), in suspension volume 2.14 dm 3 . Solid phase was 10.50 g zeolite NaX, size 0.063-0.09 mm, and liquid phase is (II) copper nitrate. Kinetic analysis of experimental results found that the ion exchange process is fast in the initial period and then decelerate till equilibrium is reached. For the kinetic analysis Ritchie and Morris-Weber models are used. Ritchie model showed better fit with the experimental data
Influence of ultrasonic irradiation on complete suspension state of borax in crystallizer equipped by SBT impeller : bachelor thesis
No full textCilj rada bio je ispitati utjecaj ultrazvuĉnog djelovanja na postizanje stanja potpune suspenzije kristala dinatrijevog tetraborat dekahidrata (boraks) u kristalizatoru sa SBT miješalom. OdreĊivanje minimalne brzine vrtnje miješala za postizanje stanje potpune suspenzije, , uz i bez primjene ultrazvuka provedeno je na laboratorijskom šaržnom kristalizatoru u kojem je volumen suspenzije iznosio 2.6 dm 3 , uz primjenu Zwieteringova kriterija "1s". Ispitivanja su provedena s tri razliĉita promjera radijalnog SBT miješala i pri ĉetiri razliĉite amplitude jakosti ultrazvuka = 20 − 40% . Eksperimentalni rezultati ukazuju da primjena ultrazvuka smanjuje vrijednost u ispitivanom reaktorskom sustavu. MeĊutim, sugerira se korištenje manjih amplituda jakosti ultrazvuka (= 20%) s obzirom na to da daljnjim povećanjem intenziteta ultrazvuka vrijednosti se dodatno ne smanjuju, dok se ukupni utrošak snage miješanja znaĉajno povećava. Za ispitivanu geometriju šaržnog kristalizatora te ispitivanu koncentraciju i odreĊenu veliĉinu kristala boraksa izvedena je korelacijska jednadžba koja povezuje vrijednosti sa amplitudom jakosti ultrazvuka i simpleksa (D/(T)The aim of this research was to examine the influence of the ultrasound on the state of complete suspension of the sodium tetraborate decahydrate (borax) crystals in the crystallizer with SBT impeller. Determination of minimal impeller speed required to achieve a state of complete suspension, N JS, with or without the ultrasound, was conducted in the laboratory scale batch crystallizer with a suspension volume of 2.6 dm 3 , using Zwietering's criterion "1s". The tests were carried out at three different diameters of the radial SBT impeller and at four different amplitudes of the ultrasound (= 20 − 40%) . Experimental results showed that ultrasonic irradiation reduces the value of N JS in the examined reactor system. Nevertheless, it is suggested to use lower amplitudes of the ultrasound = (20%) since with the increasement of the ultrasound intensity N JS is not additionally reduced, while total power consumption of mixing is significantly increased. For the examined geometry of the batch crystallizer, the concentration and size of the borax crystals, an equation which correlate the N JS value with the ultrasound amplitude and simplex (D/T) was derived