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Ispitivanje oksido - redukcijskih svojstava ((1E)-1-N-{[4-(4-{[(E)-N-(2-aminofenil) karboksiimidoil] fenoksi}butoksi)fenil]metiliden}benzen-1,2-diamina uporabom cikličke voltametrije
No full textU ovome radu opisana je uporaba cikličke voltametrije u svrhu ispitivanja oksidoredukcijskih svojstava novosintetizirane Schiffove baze ((1E)-1-N-{[4-(4-{[(E)-N-(2-aminofenil) karboksiimidoil] fenoksi} butoksi) fenil] metiliden} benzen- 1,2 -diamin, S36. Snimanjem cikličkih voltamograma pratila se oksidacija i redukcija dviju amino skupina navedene Schiffove baze. Dobiveni rezultati cikličkih voltamograma snimljenih na elektrodi od staklastog ugljika pokazali su da se Schiffova baza S36 ireverzibilno oksidira. Također se pratio utjecaj promjene koncentracije Schiffove baze S36 pri brzini promjene potencijala od 100 mV/s, te utjecaj brzine promjene potencijala u rasponu od 25 mV/s do 300 mV/s. Pri ovakvim uvjetima visina oksidacijskog strujnog vrha povećavala se s povećanjem koncentracije ispitivane Schiffove baze kao i s brzinom promjene potencijala.In this work, a usage of cyclic voltammetry for the purpose of testing oxido-reduction properties of a newly synthesized Schiff base (1E)-1-N-{[4-(4-{[(E)-N-(2-aminophenyl) carboxyimidoyl] phenoxy} butoxy) phenyl] methilidene} benzene -1,2-diamine, S36 is described. By recording cyclic voltammograms, oxidation and reduction of two amino groups of the mentioned Schiff base were followed. Gained results of the cyclic voltammograms, recordered on glassy carbon electrode, showed that the Schiff base S36 oxidated irreversibly. Also, an influence of concentration change of the Schiff base S36 at scan rate 100 mV/s and influence of scan rate in range between 25 mV/s and 300 mV/s were followed. At these conditions, oxidation peak current was increasing with an increase of a concentration of the tested Schiff base, and scan rate
Struktura i funkcija ATP-sintaze
No full textATP-sintaza je kompleksni protein odgovoran za katalizu sinteze ATP-a i katalize hidrolize ATP-a. Nalazi se u svim organizmima, od bakterija do čovjeka. Građen je od dva dijela koji rotiraju, F0 i F1. F0 dio je građen od ab2c10-15 podjedinica, ali može imati i još dodatnih podjedinica ovisno o organizmu. F0 dio se nalazi kod pozitivne strane (P), strana sa visokim elektrokemijskim potencijalom protona. U F0 dijelu se događa protok protona uz rotaciju c prstena. F1 dio je građen od α3β3-prstena koji se rotira. F1 dio se također sastoji od γ-, ε- i δ-podjedinice. F1 dio se nalazi kod negativne strane (N), strana sa niskim elektrokemijskim potencijalom protona. Sinteza i hidroliza ATP-a se događa u β podjedinici. U nekom trenutku svaka β podjedinica se nalazi u različitoj konformaciji. Ovakav mehanizam rada ne postoji niti u jednom drugom biološkom sustavu. ATP-sintaza iako je mali protein vrlo je efikasan.ATP synthase is a complex protein. It catalyzes synthesis of ATP and also it catalyzes its hydrolysis. It is found in all organisms, from bacteria to man. It is built from two units that rotate, F0 and F1. F0 consists of ab2c10-15 subunits, but it can also have other additional subunits, depending in which organism it is. F0 is situated on the positive side (P), side with a high electrochemical proton gradient. In F0 happens the rotational flow of protons. F1 is built from α3β3-ring which rotates. It also consists of γ-, ε- and δ-subunits. F1 is situated on the negative side (N), side with a low electrochemical proton gradient. Synthesis and hydrolysis happen in β subunits. In any time of the synthesis or hydrolysis the tree β subunits have different conformations. This mechanism is not found in any other biological system. Although ATP synthase is a small protein it is highly efficient
Priprema kemometričkih metoda u analizi koncentracija zračnih onečišćivača - analiza višegodišnjih mjerenja
No full textU ovome radu obrađeni su podatci satnih koncentracija PM2,5, O3, H2S, temperature, relativne vlage i brzine vjetra prikupljeni tijekom perioda 2010. do 2013. godine s mjerne stanice za motrenja zagađenja zraka smještene na području Slavonskog Broda. Upotrijebljene su metoda analiza glavnih komponenata i metoda Fourierovih transformacija. Metodom analize glavnih komponenata s rotacijom faktora utvrđene su relativno slabe pozitivne korelacije između ozona i temperature i relativno jake negativne korelacije između sumporovodika i vjetra. Fourierovom analizom provedenom na 157 158 podataka (26 193x6), pored postojanja uobičajenih 24- satnih ciklusa u svim istraživanim varijablama, utvrđeno je postojanje različitih ciklusa u potpunosti istih brojčane vrijednosti, koji su se kretali u rasponu od dvogodišnjih, jednogodišnjih, polugodišnjih do dvomjesečnih. Iznimku su činili podatci vrijednosti satnih koncentracija PM2,5 gdje su, uz nabrojane, nakon provedene analize uočeni i ciklusi od 23 i 80 dana, ali i podatci satnih vrijednosti temperature i relativne vlage gdje su uočeni dodatni ciklusi u rasponu od 50 do 124 dana. Ciklusi manji od 24- satnog nisu pronađeni niti u jednom slučaju, kao niti ciklusi koji bi se odnosili na moguće utjecaje antropogenih faktora (7- dnevni npr.)In this paper concentrations of PM2,5, O3, H2S, temperature, relative humidity and wind speed, were processed. All of them were measured from 2010 to 2013 in Slavonski Brod. In order to investigate the effects of air pollutants, Principal Components Analysis (PCA) method and Fourier analysis were applied. Principal Components Analysis (PCA) method revealed relatively weak positive correlation between O3 and temperature but also relatively strong negative correlation between H2S and wind. Fourier analysis was used for a large amount of data and, apart from ordinary 24- hour cycle in observed variables, other cycles were determined but they all had same value: one or two years and two months. PM2,5 were exception because, beside already listed cycles, they had cycles of 23 and 80 days. It was not possible to relate human factors and concentrations of air pollutants since there were no cycles less than 24-hours cycle
Determination of anionic surfactants by the two-phase titration in the real system
No full textTenzidi su površinski aktivne tvari koje smanjuju napetost površine. Sastoje se od "glave" (hidrofilni dio) i "repa" (hidrofobni dio). Rep čini dugi ugljikovodični lanac, dok su glave pozitivne, negativne ili neutralne grupe. Tenzidi se dijele na kationske, anionske, neionske i amfolitske tenzide. Glave anionskih tenzida čine negativno nabijene grupe kao što su karboksilatni ion (-COO-), sulfonatni ion (-SO3-), sulfatni ion (-OSO32-). Anionski tenzidi su visoko-pjeneće aktivne tvari, dobro se raspršuju u vodi i sastavni su dio praškastih deterdženata kao i deterdženata za pranje suđa. Anionski tenzidi mogu se analizirati titracijskim metodama, spektrofotometrijskim metodama, kromatografskim metodama i analitikom s injektiranjem u protok. Titracijske se metode zasnivaju na stvaranju ionskih asocijata između anionskog tenzida i kationskog titranta. Titracija u dvije faze je referentna metoda za određivanje anionskih tenzida. Spada u vizualnu titraciju kod koje je korišten Hyamin 1622, kao kationski titrant, koncentracije 4,16 x 10-3 mol/L uz otopinu miješanog indikatora. Za njegovu standardizaciju korištena je standardna otopina natrijeva dodecil sulfata (NaDDS), koncentracije 4 x 10-3 mol/L. Nakon standardizacije provedene su titracije realnih uzoraka koji prema deklaraciji sadrži manje od 5 % , 5 - 15 % i 15 - 30 % anionskih tenzida.Surfactants are surface active agents that lower the surface tension. They consist of a "head" (hydrophilic part) and "tail" (hydrophobic part). The tail consists of a long hydrocarbon chain, while the heads of positive, negative or neutral groups. Surfactants are classified as cationic, anionic, nonionic surfactants and ampholitic. Heads of anionic surfactants are formed of negatively charged groups such as carboxylate ion (-COO-), a sulfonate ion (-SO3-), sulphate ion (-OSO32-). Anionic surfactants are high-foaming active ingredients, are well dispersed in water and are an integral part of powder detergents as well as detergents for dishwashing. Anionic surfactants can be analyzed by titration method, by using spectrophotometric methods, chromatographic methods and by flow injection analysis. Titration methods are based on the creation of ion associates between anionic surfactants and cationic titrant. Two-phase titration is the reference method for the determination of anionic surfactants. It includes a visual titration with Hyamin 1622, a cationic titrant (concentration 4.16 x 10-3 mol / L) with a mixed indicator solution. A standardization of Hyamin 1622 was done by using a standard solution of sodium dodecyl sulfate (NaDDS), concentration of 4 x 10-3 mol / L. After standardization titrations were performed in real patterns that by the declaration contains less than 5 %, 5 - 15 % and 15 - 30 % of anionic surfactant
Monitoring of anionic surfactants in wastewater of detergent industries for February 2014.
No full textKoncentracija anionskih tenzida u otpadnim vodama detergentske industrije za veljaču 2014. godine praćena je i određivana potenciometrijskim titracijama upotrebom tenzidnog senzora. Uzorkovanje je provedeno u tijeku jednog dana, iz odvodnog sustava: uzorak 1 i uzorak 2 su uzorkovani u 11 sati, uzorak 3 i uzorak 4 u 12 sati, a uzorak 5 i uzorak 6 u 13 sati. Za mjerenja je korištena tenzidna elektroda koja je u sastavu senzorske membrane imala lipofilne elektroaktivne tvari, 1,3-didecil-2-imidazol-tetrafenilborat i PVC kao plastifikator. Kao titrant je korišten kationski tenzid cetilpiridinijev klorid. Tenzidna elektroda pokazala je linearni odziv u području koncentracija od 10-3 do 10-6 moldm-3. Koncentracije titranta prilagođene su uzorcima analita; korištene su koncentracije: 2×10-5 moldm-3 za uzorke 1, 3, 5 i 2×10-4 moldm-3 za uzorke 2, 4, 6. Iz prve derivacije određene su završne točke titracija te su pomoću njih izračunate koncentracije anionskih tenzida u uzorcima kako slijedi: uzorak 1 sadrži 6,37 mgdm-3, uzorak 2 77,32 mgdm-3, uzorak 3 11,27 mgdm-3, uzorak 4 83,06 mgdm-3, uzorak 5 12,13 mgdm-3, uzorak 6 48,69 mgdm-3. Statistička obrada podataka pokazuje zadovoljavajuću standardnu devijaciju, odstupanje rezultata do 10 %. Dozvoljena granica za anionske tenzide u otpadnim vodama iznosi 5 mgdm-3. Provjera rezultata provedena je na dva načina: a) u neovisnom laboratoriju ponovljena je direktna potenciometrijska metoda uz upotrebu tenzidne elektrode, b) primijenjena je referentna metoda za anionske tenzide (Methylene Blue Active Substances -MBAS). Vrijednosti koncentracija dobivene različitim metodama nisu se značajno razlikovale. U metodičkom dijelu diplomskog rada obrađena je tema "Sapuni i drugi površinski aktivni spojevi". Tema je osmišljena tako da učenici sami kroz metode razgovora i demonstracije povezuju već postojeća znanja kako bi usvojili novu nastavnu cjelinu. Tema je pripremljena za četvrti razred gimnazije. Uz pripremu za nastavu osmišljena su dva pokusa s radnim listićima: "Svojstva sapuna i detergenata" te "Sapuni i detergenti smanjuju površinsku napetost vode".The anionic surfactants concentration in wastewaters of detergent industry for Ferbruary 2014 was monitored and determinated by potetiometric titratons using surfactant sensor. Sampling was performed in one day from the wastewater system pipelines: sample1 and sample 2 were sampled at 11 am, sample 3 and sample 4 at 12 pm and sample 5 and sample 6 at 13 pm. Measurements were performed by the surfactant electrode composed of lipophilic electroactive substances 1,3-didecyl-2-methylimidazoliumtetraphenylborate and PVC as plasticizer. As a titrant is used cationic surfactant cetylpyridinium chloride. Surfactant electrode showed a linear response in the concentration range from 10-3 to 10-6 moldm-3. The titrant concentrations are adapted to the samples; concentrations: 2 × 10-5 moldm-3 for samples 1, 3, 5 and 2 × 10-4 moldm-3 for samples 2, 4, 6. The titrations end points were determinated by the first derivation. Calculated concentration of anionic surfactants in the samples were as following: sample 1 contains 6,37 mgdm-3, sample 2 77,32 mgdm-3, sample 3 11,27 mgdm-3, sample 4 83,06 mgdm-3, sample 5 12,13 mgdm-3, sample 6 48,69 mgdm-3.Statistical analysis of the data shows a satisfactory standard deviation, up to 10%. The legislation permits level of anionic surfactants in wastewater is 5 mgdm-3. The results were compared by means of two methods: a) direct potentiometry using tenzide electrode was repeated in an independent laboratory, b) the reference method for anionic surfactants (Methylene Blue Active Substances - MBAS) was applied. The concentration values obtained using different methods did not significantly differ. In the teaching part of the thesis a preparation lecture on "Soaps an other surface-active compounds" for the fourth year of high school chemistry class is proposed. The students are supposed to discuss and perform experiments merging existing partial knowledge in order to adopt new lesson unit. Additionally, two experiments "Properties of soaps and detergents" and "Soaps and detergents reduce the surface tension of water" with worksheets are prepared
Sinteza i karakterizacija kompleksnih spojeva prijelaznih metala s acetilacetonom
No full textSintetizirani su spojevi prijelaznih metala s acetilacetonom kao ligandom. Ukupno je sintetizirano sedam spojeva. Kao polazni reaktanti su korištene soli prijelaznih metala i acetilaceton. U ovom se radu sintetizirani su kompleksi željeza, kobalta, bakra, nikla i cinka s acetilacetonom, a potom su snimljeni IR spektri kako bi se odredile pojedine funkcionalne skupine. Potom su spojevi analizirani termičkom analizom. Cilj sinteze jest predvidjeti koordinaciju dobivenoga kompleksa.Complex compounds of transition metals with acetylacetone as a ligand are sinthesyzed. A total of seven compounds were sinthesyzed. As starting reactants are used salts of transition metals and the solution of acetylacetone. In this paper were synthesized complexes of iron, cobalt, copper, nickel and zinc with acetylacetone, and then the IR spectra were recorded to determine the individual functional groups. Afterwards, the compounds were analyzed by thermal analysis. The goal of these synthesis is to predict the coordination obtained complexes
Priprava srebrovih soli s hidroksi karboksilnim i masnim kiselinama
No full textTema, a ujedno i cilj ovoga rada jest sinteza srebrovih soli s hidroksikarboksilnim i masnim kiselinama. U radu će se raspravljati kako o sintezi tako i o analizi spomenutih spojeva. Za sintezu srebrovih soli korištene su limunska, salicilna, oleinska i stearinska kiselina. Glavni prekursor u svim sintezama bila je jedna od najpoznatijih srebrovih soli, srebrov nitrat. Kako bi se pobliže otkrila molekulska struktura i graĎa ovih spojeva korištene su metode infracrvene spektroskopije (FTIR) i termogravimetrijske analize (TGA).The topic and a goal of this paper is a synthesis of silver salts with hydroxycarboxylic and fatty acids. Their synthesis and analysis will be described and discussed. Acids used in synthesis were citric acid, salicylic acid, oleic acid, and stearic acid. Main precursor in the synthesis was silver nitrate. TGA and FTIR were used for determination of molecular structure
Priprava i karakterizacija kompleksnih spojeva s makrocikličkim Schiffovim bazama
No full textOvaj rad opisuje sintezu dviju Schiffovih baza. Jedna baza je dobivena iz dialdehida 2-[5- (2-formilfenoksi)pentoksi]-benzaldehida i m-fenilendiamina, dok je druga dobivena iz drugog aldehida 2-[4-(2-formilfenoksi)butoksi]-benzaldehida i istog diamina mfenildiamina. Dobivene Schiffove baze su korištene u reakcijama sa solima prijelaznih metala: srebrovim (I) nitratom i živinim (II) nitratom monohidratom. Analiza baza izvršila se IR-spektroskopijom, a analiza kompleksa izvršila se IR-spektroskopijom i termičkom analizom (TGA-DSC). Analizom produkata koji su nastali reakcijom Schiffovih baza s anorganskim solima: srebrovim (I) nitratom i živinim (II) nitratom monohidratom, uočen je nastanak kompleksnih spojeva sa makrocikličkim Schiffovim bazama.This work describes the synthesis of two Schiff bases. One of the bases is derived from dialdehyde (2-[5-(2-formylphenoxy)pentoxy]-benzaldehyde and m-phenylenediamine, while another base is derived from 2-[4-(2-formylphenoxy)butoxy]-benzaldehyde) and from same diamine m-phenylenediamine. Obtained Schiff bases were used ih reactions with salts of transition metals: silver (I) nitrate and mercury (II) nitrate monohydrate. Analysis of the bases was made with the IR spectroscopy and analysis of complex compounds was made with the IR spectroscopy and thermal analysis (TGA-DSC). Analysis of products that were synthesized in the reaction between the Schiff bases and inorganic salts: silver (I) nitrate and mercury (II) nitrate monohydrate shows that complex compounds with macrocyclic Schiff bases are derived
Stereoselektivna redukcija karbonilnih spojeva pomoću enzimskih sustava iz biljnog materijala
No full textKiralni alkoholi su važne građevne jedinice za sintezu farmaceutskih pripravaka, pesticida, feromona, aroma, mirisa i materijala poput tekućih kristala. U ovome je radu opisana redukcija jednostavnih ketona, aromatskih ketona s halogenom i ß-ketoestera u kiralne alkohole korištenjem enzima iz biljnih materijala. Acetofenon je reduciran u 1 - feniletanol korištenjem različitih biljnih kultura. Kao biokatalizatori korišteni su mrkva (Daucus carota), komorač (Foeniculum vulgare) i tikvice (Cucurbita pepo). Uz pomoć kulture Daucus carota dobiven je čisti (S)-feniletanol uz enantiomerni višak od 100 %. Z. H. Yang i suradnici su proveli redukciju 4'-kloracetofenona u (R)- ili (S)-1-(4- klorfenil)etanol i etil-4-kloracetoacetata u etil-(S)-(-)-4-klor-3-hidroksibutanoat korištenjem različitih biljnih kultura. Najbolji rezultati dobiveni su korištenjem kulture Daucus carota.Chiral alcohols are important building blocks for the synthesis of pharmaceuticals, pesticides, pheromones, flavors, fragrances and advanced materials such as liquid crystals. This work describes reduction of simple ketones, halogen-containing aromatic ketones and ß-ketoesters to chiral alcohols by enzymes from plant systems. Acetophenone is reduced to 1-phenylethanol by various plant tissues. As biocatalysts were used carrot (Daucus carota), fennel (Foeniculum vulgare) and marrow (Cucurbita pepo). Reduction of acetophenone by cultures Daucus carota afforded pure (S)-phenylethanol with 100% enantiomeric excess. Z. H. Yang and co-workers performed reduction of 4'- chloroacetophenone to (R)- or (S)-1-(4-chloro-phenyl)ethanol and ethyl-4- chloroacetoacetate to ethyl-(S)-(-)-4-chloro-3-hidroxybutanoate by various plant tissues. The best results were obtained using cultures Daucus carota
Termičke i spektroskopske karakteristike metalnih kompleksa s amonijakom
No full textU ovom završnom radu su izrađeni kompleksi heksaaminniklov (II) klorid, tetraaminbakrov (I) sulfat, kloropentaaminokobaltov (III) klorid i diaminosrebrov (I) sulfat. Nadalje, objašnjena je infracrvena spektroskopija i postupak termičke analize spojeva, te princip rada FTIR spektrometra i TGA/DSC uređaja kojima su izvršena mjerenja. Na kraju rada prikazani su i objašnjeni rezultati IR i TGA/DSC analize pripremljenih kompleksnih spojeva.In this investigation we have synthesized hexaaminnickel(II) chloride complex, tetraamincopper (II) sulfate, chloropentaamincobalt(III) chloride and diaminosilver(I) sulfate. Furthermore, we have explained principles of infrared spectroscopy and thermal analysis, that were also methodes that were used for characterization of synthesized compounds. At the end of the work identifies and explains the results of IR and TGA / DSC analysis of prepared complex compounds