Reakcije sinteze i termodinamika stvaranja spoja tijekom sinteriranja sloja MoMn

Chemical reactions and thermodynamics of high temperature alumina metallization have been investigated. During the firing of MoMn paste, reactions start with oxidation of manganese. The formed Mn3O4 reacts with alumina and SiO2 at a temperature lower than 1200 °C. The formation of the metallizing layer is a consequence of lowering of the free energy of the system. It is caused by redox and dissolution reactions, the formation of the glass phase and crystallization process from the liquid phase. With available thermodynamical data and according to the atmospheric conditions, some reactions were predicted and confirmed by X-ray diffraction.Istraživane su kemijske reakcije i termodinamika visokotemperaturne metalizacije korunda. Tijekom paljenja smjese MoMn, reakcije počnu oksidacijom mangana. Nastali Mn3O4 reagira s korundom i SiO2 na temperaturi ispod 1200 ◦C. Nastajanje metalnog sloja je posljedica smanjenja slobodne energije sustava. Smanjenje je posljedica redoks reakcije, odvajanja faza, nastajanja staklene faze i kristalizacije iz tekuće faze. Neke su reakcije predvidene i potvrđene rendgenskom difrakcijom

Reakcije sinteze i termodinamika stvaranja spoja tijekom sinteriranja sloja MoMn

Chemical reactions and thermodynamics of high temperature alumina metallization have been investigated. During the firing of MoMn paste, reactions start with oxidation of manganese. The formed Mn3O4 reacts with alumina and SiO2 at a temperature lower than 1200 °C. The formation of the metallizing layer is a consequence of lowering of the free energy of the system. It is caused by redox and dissolution reactions, the formation of the glass phase and crystallization process from the liquid phase. With available thermodynamical data and according to the atmospheric conditions, some reactions were predicted and confirmed by X-ray diffraction.Istraživane su kemijske reakcije i termodinamika visokotemperaturne metalizacije korunda. Tijekom paljenja smjese MoMn, reakcije počnu oksidacijom mangana. Nastali Mn3O4 reagira s korundom i SiO2 na temperaturi ispod 1200 ◦C. Nastajanje metalnog sloja je posljedica smanjenja slobodne energije sustava. Smanjenje je posljedica redoks reakcije, odvajanja faza, nastajanja staklene faze i kristalizacije iz tekuće faze. Neke su reakcije predvidene i potvrđene rendgenskom difrakcijom

Mouthwashes

A mouthwash may be recommended as an antimicrobial, a topical anti-inflammatory agent, a topical analgesic, or for caries prevention. Many different mouthwashes are commercially available and patients and health professionals struggle to select the most appropriate product for a particular need. The selection needs to take into consideration factors such as the patient's oral condition, their disease risk and the efficacy and safety of the mouthwash. Mouthwashes are an adjunct to, not a substitute for, regular brushing and flossing

Nutritivna vrednost kukuruznog stočnog brašna u ishrani pilića u tovu

One of the by-products of corn processing which can successfully be used in poultry nutrition is livestock meal. In this trial corn meal was investigated, meal in two form: non-extruded (T1 and T2) and extruded (T3 and T4) as a replacement of cracked corn (K) in the amount of 100% (T1 and T3) and 50% (T2 and T4). Investigation was carried out in 4 repetitions, 75 chickens of Arbor Acres x Ross 308 hybrid in each group. Trial lasted 42 days. Chickens were fed three standard mixtures (starter, grower and finisher). Investigation demonstrated that group of chickens of treatment T3 realized the best final body masses (2254g), followed by chickens in treatment T4 (2173g), chickens of group T2 (2112g), K group (2106 g), and the worst results were established in chickens of group T1 (2103g). It was established that differences in final body mass of chickens from group T3 in relation to chickens from groups T1, T2, T4 and were statistically highly significant (P (lt) 0,001). Statistically significant differences (P (lt) 0,05) were established between body masses of chickens from group T4 in relation to T1, T2 and K group. Mortality of chickens was as followes: K-3,64%, T1- 2,50%, and T2-5,00%, T3-6,39%, and T4-3,33%. Feed conversion in all investigated groups was almost identical (K-1,91; T2-,93; T3-1,93; T4-1,94) with the exception of T1 with 1,97. In regard to production index (PI), the best results were realized by group of chickens T3 (261), followed by chickens T4 (258), K (253), and the worst results were established in chickens of groups T1 (248) and T2 (248).U radu je dat efekat primene neekstrudiranog (T1 i T2) i ekstrudiranog (T3 i T4) kukuruznog stočnog brašna u ishrani brojlerskih pilića. U smešama kukuruz (K) je zamenjen kukuruznim stočnim brašnom u iznosu 50% (T2 i T4) i 100% (T1 i T3). Ogled je trajao 42 dana po sistemu 5 x 4 (5 tretmana x 4 ponavljanja). U svakom tretmanu je bilo po 300 pilića. Ishrana je bila ad libitum sa tri smeše: starter sa 23,30% SP i 12,78 MJ/kg ME, grover sa 20,30% SP i 13,10 MJ/kg ME, i finišer 17,70% SP i 13,25 MJ/kg ME. Rezultati ispitivanja su bili sledeći: telesne mase K-2106g, T1-2103g, T2-2112g, T3-2254g, i T4-2173g; dnevni prirast K-50,13g, T1-50,08g, T2- 50,29g, T3-53,66g, i T4-51,73g; mortalitet pilića K-3,64%, T1-2,50%, T2- 5,00%, T3-6,39%, i T4-3,33%; Konverzija hrane K-1,91 kg/kg, T1-1,97 kg/kg, T2-1,93 kg/kg, T3-1,93 kg/kg, i T4-1,94 kg/kg. Pokazalo se da su razlike u završnoj telesnoj masi pilića iz T3, u odnosu na T1, T2, T4 i K grupe, bile statistički visoko značajne (P (lt) 0,001). Utvrđene su statistički značajne razlike (P (lt) 0,05) između telesnih masa grupe pilića T4 u odnosu na T1, T2 i K grupe. Randmani su bili ujednačeni po grupama, a razlike u sadržaju abdominalne masti u trupovima su bile minimalne ali nešto niže kod petlića i kojica grupe T1 i petlića T2. Razlike su bile su statistički značajne

Discrimination of mineral waters using near-infrared spectroscopy and aquaphotomics

Voda je jedan od najčešće proučavanih materijala danas, ali uprkos tome mnoga njena svojstva i dalje ostaju nerazjašnjena i neiskorišćena. Voda je neophodna za normalno funkcionisanje ljudskog organizma, između ostalog zbog toga, poremećaji homeostaze vode u ljudskom telu leže u osnovi mnogih bolesti. Analiza vode i njene ispravnosti za upotrebu u ljudskoj ishrani uglavnom se bavi onim što je prisutno u vodi - koncentracijama prisutnih anjona i katjona, prisustvu mikroorganizama i tome slično. Različite vrste voda se uglavnom i klasifikuju upravo prema vrsti elemenata koje sadrže, koncentraciji prisutnih elemenata, ili pak odnosu između koncentracije pojedinih jona i njihov efekat na ljudski organizam razmatra se isključivo sa stanovišta elemenata koji su prisutni u njoj. Međutim, iako je poznato da voda formira različite tipove klastera i može da se organizuje oko prisutnih elemenata na različite načine, klasifikacija voda na osnovu organizacije vodenih molekula, kao i efekti različito klasterizovanih voda na ljudski organizam, za sada ne postoje u literaturi. Predmet ovog rada je diskriminacija različitih tipova voda na osnovu njihovog spektra u bliskoj infracrvenoj oblasti, primenom multivarijacione analize i novog pristupa za tumačenje spektara vode u ovoj oblasti, poznatog pod nazivom Akvafotomika. Akvafotomika interpretira spektar vode u bliskoj infracrvenoj oblasti preko posebno definisanih koordinata vodene mreže (water matrix coordinates - WAMACS) kojima su pripisani tačno određeni vibracioni modovi molekula vode preko kojih se može zaključiti kako se molekuli vode organizuju. Na taj način, primenom saznanja akvafotomike, voda se može opisati i sa aspekta njene organizacije u klastere, i time se omogućiti i diskriminacija voda na osnovu prisutnih tipova klastera što je prikazano u ovom radu.Despite that water is one of the most studied materials today its dynamic properties are still not well understood. Water state in human organism is of high importance for normal healthy functioning of human body. Different kinds of water are usually classified according to their present solutes and concentrations of these solutes, but though it is known that water molecules can form clusters around present solutes, the classification of waters based on types of water molecular organization and present clusters is not present in current literature. In this study the multivariate analysis is used for classification of commercial mineral waters based on their near-infrared spectra (NIR). Further, the aquaphotomics has been applied, a new approach for interpretation of near-infrared spectra of water, that gives insight into organization of water molecules in each of these waters

Discrimination of mineral waters using near-infrared spectroscopy and aquaphotomics

Voda je jedan od najčešće proučavanih materijala danas, ali uprkos tome mnoga njena svojstva i dalje ostaju nerazjašnjena i neiskorišćena. Voda je neophodna za normalno funkcionisanje ljudskog organizma, između ostalog zbog toga, poremećaji homeostaze vode u ljudskom telu leže u osnovi mnogih bolesti. Analiza vode i njene ispravnosti za upotrebu u ljudskoj ishrani uglavnom se bavi onim što je prisutno u vodi - koncentracijama prisutnih anjona i katjona, prisustvu mikroorganizama i tome slično. Različite vrste voda se uglavnom i klasifikuju upravo prema vrsti elemenata koje sadrže, koncentraciji prisutnih elemenata, ili pak odnosu između koncentracije pojedinih jona i njihov efekat na ljudski organizam razmatra se isključivo sa stanovišta elemenata koji su prisutni u njoj. Međutim, iako je poznato da voda formira različite tipove klastera i može da se organizuje oko prisutnih elemenata na različite načine, klasifikacija voda na osnovu organizacije vodenih molekula, kao i efekti različito klasterizovanih voda na ljudski organizam, za sada ne postoje u literaturi. Predmet ovog rada je diskriminacija različitih tipova voda na osnovu njihovog spektra u bliskoj infracrvenoj oblasti, primenom multivarijacione analize i novog pristupa za tumačenje spektara vode u ovoj oblasti, poznatog pod nazivom Akvafotomika. Akvafotomika interpretira spektar vode u bliskoj infracrvenoj oblasti preko posebno definisanih koordinata vodene mreže (water matrix coordinates - WAMACS) kojima su pripisani tačno određeni vibracioni modovi molekula vode preko kojih se može zaključiti kako se molekuli vode organizuju. Na taj način, primenom saznanja akvafotomike, voda se može opisati i sa aspekta njene organizacije u klastere, i time se omogućiti i diskriminacija voda na osnovu prisutnih tipova klastera što je prikazano u ovom radu.Despite that water is one of the most studied materials today its dynamic properties are still not well understood. Water state in human organism is of high importance for normal healthy functioning of human body. Different kinds of water are usually classified according to their present solutes and concentrations of these solutes, but though it is known that water molecules can form clusters around present solutes, the classification of waters based on types of water molecular organization and present clusters is not present in current literature. In this study the multivariate analysis is used for classification of commercial mineral waters based on their near-infrared spectra (NIR). Further, the aquaphotomics has been applied, a new approach for interpretation of near-infrared spectra of water, that gives insight into organization of water molecules in each of these waters

Biocompatibility and cytotoxicity study of nanophotonic rigid gas permeable contact lens material

Since materials on nanoscale have different characteristics from materials on macro scale their biocompatibility should be precisely and specifically investigated. Fullerenes, the third carbon allotrope, are one of the most used nanomaterials. The least stable and the most common is fullerene C-60. One of the main disadvantages of fullerene is its low solubility in water. In order to make it soluble, it must be functionalized with polar groups such as -OH and -COOH. From all the water soluble fullerenes the most important ones are those with -OH groups attached named fullerols. We have developed new materials for contact lenses by adding fullerene (C-60) and fullerol (C-60(OH)(24)) into PMMA. The aim of our investigation was to compare the influences of those materials on aqueous solutions similar to tear film. For the analysis of the solutions we used opto-magnetic imaging and IR spectroscopy. The acquired spectrums were commented and compared with the standard contact lens material, which was analyzed by the same methods. The ISO 10993 cytotoxicity test on extract of nanophotonic material with incorporated C-60 was done as well. This research contributes to better understanding of the biocompatibility of new rigid gas permeable contact lens materials

Aquagrams: Water spectral pattern as characterization of hydrogenated nanomaterial

Akvafotomika je novi pristup u nauci o određivanju osobina vode, vodenih rastvora i prisustva u malim koncentracijama biomolekula i nanomaterijala u vodi. Ova metoda se zasniva na karakterističnim frekvencijama vode u infracrvenom (IR) spektru na osnovu kojih se izrađuje dijagram oblika 'paukove mreže'. Promene u spektralnom dijagramu 'paukove mreže' čiste vode, daje informaciju o prisustvu i organizaciji dodate materije u vodu. Intenzitet poremećaja spektara je proporcionalan koncentraciji i organizaciji unete materije. Umesto da se identifikuju čestice (mikro, nano) u vodi, kao što je do sada bio slučaj (a što je dosta teško kada se radi o malim koncentracijama), u akvagramu se identifikuju najmanje promene matriksa vode na karakterističnim frekvencijama. Karakter i intenzitet tih promena u našem istraživanju omogućio je analizu interakciju vode i hidrogenizovanog fulerenskog nanomaterijala. Infracrvena spektroskopija, sa novim razvijenim konceptom, 'paukovom mrežom', se koristi da se ispita organizacija novo nastale supstance, kao mešavina harmonizovanog hidrogeniranog fulerena (NHS) i demineralizovane vode. Analiza akvagrama pokazuje da se NHS organizovao u formu Fibonačijevog niza (Φ/φ) i da preko vodoničnih veza deluje na okruženje. Efekat razblaživanja NHS supstance na vodu se takođe analizira pomoću akvagrama. Kako su neki biološki molekuli (mikrotubule, kolagen, klatrin i dr) uređeni po Fibonačijevom nizu to prisustvo NHS u biološkim tkivima može postati pokretačka snaga prirodnog procesa samo-reparacije, koja je u stanju da obnovi oštećene funkcije biomolekula. Ova istraživanja otvaraju mogućnost razvoja nanomedicine na bazi hidrogenizovanih nanomaterijala u vodi koji su uređeni i sposobni da generišu vibracione modove po Fibonačijemom nizu.Aquaphotomics is a novel approach in science to water and aqueous solutions investigation. It is based on near infrared spectroscopy (NIR), which in our current research is used for the analysis of interaction of water and hydrogenated nanomaterial. Infrared spectroscopy, with a new developed concept that of aquaphotomics, is used to investigate the organization of matter as a mixture of harmonized hydrogenated fullerene (nano-harmonized substance-NHS) and pure water. Composition of matter follows a harmonized form by Fibonacci law (Φ/φ). The effect of dilution on nano-harmonized substance is analyzed and the results of near infrared spectra are presented in the form of aquagrams. The presence of NHS in biological tissues is a driving force of natural self-assembly process, which is capable of restoration of damaged functions of biomolecules

Characterization of fullerenes thin film on glasses by UV/VIS/NIR and opto-magnetic imaging spectroscopy

UV/VIS ispitivanje stakala za naočare je deo standardne procedure. Razlog za to jeste da se osigura UV zaštita oka, kao i karakterizacija transparentnosti materijala. Međutim, mi smo proširiti ovo istraživanje u IR domenu iz razloga što kvalitet stakala ne zavisi samo od UV zaštite i njihove transparentnosti, već takođe i od komplementarnosti i kompatibilnosti oka sa optičkim pomagalom. Izvršena je karakterizacija osnovnog materijala za naočare pomoću UV/VIS/NIR i nove metode opto-magnetne imidžing spektroskopije. Nakon toga osnovni materijal dopiran je fulerenom, i izvršena je karakterizacija primenom istih metoda. Rezultati su predstavljeni i diskutovani.UV/VIS spectroscopic characterization of glasses is a part of the standard procedure. The reasons to do it is to ensure UV eye protection and characterization of material transparency. However, we extend this research to IR domain because the quality of glasses depend not only on UV protection and their transparency but on complementarities and compatibility of eye vision with optical device, also. We characterized basic material of glasses by UV/VIS/NIR and novel method Opto-magnetic Imaging Spectroscopy (OMIS). Then we doped basic material with fullerenes, and characterized them using the same procedure. Results are presented and discussed