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Naslov portalaDigitalne zbirke NSK
  
rrep
 
16.634 (6.521-6.530)
NaslovKinesiology : international journal of fundamental and applied kinesiology / editor-in-chief Dragan Milanović.
ImpresumZagreb : Faculty of Kinesiology, University of Zagreb, 2006- .
Materijalni opis1 online jedinica građe.
Vrsta publikaciječasopisneomeđena građa
rrep
6.521
Naslov[Kineski slavoluk. Lustberg. Viseći most] / [Johann Bernhard Fischer von Erlach].
Impresum[prije 1712].
Materijalni opis1 crteža : olovka, tuš, lavirani tuš ; 342 x 465 mm.
OpisCrtež a: Slavoluk, u drugom planu nizovi kuća; crtež b: Stijena sa stubama; crtež c: Stjenoviti pejzaž s crnogoričnim drvećem i mostom preko provalije.
rrep
6.522
NaslovKinetic evaluation of the charge migration and H2O2 transport rates during the electrocatalytic reduction of H2O2 on thin Prussian blue films / Egon Rešetar, Sandra Čičić, Damir Iveković.
Materijalni opisIlustr.
Način izrade datotekeizvorno digitalna građa
Vrstačlanak
OpisKinetic analysis of the electrocatalytic reduction of H2O2 on electrodes modified with thin Prussian blue films was performed and a full set of kinetic parameters governing the rate of the electrocatalytic reaction was determined. Rate constant (κ·k') for the catalytic reaction between H2O2 and the reduced form of Prussian blue incorporating interstitial Cs+ and K+ ions was calculated to be equal to 3.1·106 and 2.3·106 cm3·mol–1 s–1, respectively. The diffusion coefficient of H2O2 and the apparent diffusion coefficient of electrons in the reduced form of Prussian blue were found to be κ·DS(H2O2) = 2.6·10–7 cm2/s and De = 2.8·10–12 cm2/s, respectively.
rrep
6.523
NaslovKinetics of epoxidized oleic acid derived from palm oil by in situ generated performic acid / Mohd Jumain Jalil, Mohd Saufi Md Zaini, Aliff Farhan Mohd Yamin, Siu Hua Chang, Norhashimah Mora, Abdul Hadi.
Materijalni opisGraf. prikazi.
Način izrade datotekeizvorno digitalna građa
Vrstačlanak
OpisEpoxidized palm oleic acid is often regarded as a highly valuable oleochemical due to its wide range of industrial applications, including cosmetics, personal care, and pharmaceutical products. In this study, oleic acid derived from palm oil with iodine value of 98.99 g/100 g, containing 75 % of oleic acid, 12 % of linoleic acid, 6.5 % of palmitic acid, and 6.5 % of stearic acid was epoxidised by in situ generated performic acid with hydrogen peroxide as oxygen donor and formic acid as active oxygen carrier in the presence of catalytic amount of inorganic acid. The rate constant for epoxidation of oleic acid was found to be 1.133 ∙ 10–3 mol–1 s–1 and activation energy was 91.12 kJ mol–1 at temperature of 75 °C. In addition, thermodynamic parameters such as enthalpy, entropy, and free energy of activation were 88.2 kJ mol–1, −67.90 J mol–1 K–1, and 88.36 kJ mol–1, respectively. Relative conversion data showed that it was possible to develop epoxides from locally available, natural, renewable resources such as palm oil.Epoksidirana palmina oleinska kiselina često se smatra vrlo vrijednom oleokemijskom tvari zbog širokog raspona industrijskih primjena, uključujući kozmetiku, osobnu njegu i farmaceutske proizvode. U ovoj studiji, oleinska kiselina potekla iz palmina ulja s jodnim brojem 98,99 g/100 g, koja sadrži 75 % oleinske kiseline, 12 % linoleinske kiseline, 6,5 % palmitinske kiseline i 6,5 % stearinske kiseline, epoksidizirana je in situ proizvedenom performičnom kiselinom s vodikovim peroksidom kao donorom kisika i mravljom kiselinom kao aktivnim nosačem kisika u prisutnosti katalitičke količine anorganske kiseline. Konstanta brzine za epoksidaciju oleinske kiseline bila je 1,133 ∙ 10–3 mol–1 s–1, a energija aktivacije 91,12 kJ mol–1pri temperaturi 75 °C. Termodinamički parametri kao što su entalpija, entropija i slobodna energija aktivacije iznosili su 88,2 kJ mol–1, −67,90 J mol–1 K–1, odnosno 88,36 kJ mol–1. Relativni podatci konverzije pokazali su da je moguće razviti epokside iz lokalnih, prirodnih i obnovljivih izvora kao što je palmino ulje.
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6.524
NaslovKinetička analiza izotermne razgradnje poli(etilen-oksida) modificiranog fenil hepta izobutil poliedarskim oligomernim silseskvioksanima / Nataša Stipanelov Vrandečić, Matko Erceg, Branka Andričić, Petra Ćerdić.
Materijalni opisGraf. prikazi.
Način izrade datotekeizvorno digitalna građa
Vrstačlanak
Napomena7. hrvatski simpozij o kemiji i tehnologiji makromolekula, Zagreb, 27.9.2019.
OpisČvrsti polimerni elektroliti na bazi poli(etilen-oksida) (PEO) i litijevih soli imaju slabu ionsku provodnost pri temperaturi uporabe, a osnovni razlog je visok stupanj kristalnosti PEO-a. Udio kristalne faze u PEO-u može se smanjiti dodatkom nanočestica, u koje spadaju i poliedarski oligomerni silseskvioksani (POSS). U ovom radu upotrijebljeni su metil-, fluoro- i kloro-fenil hepta izobutil poliedarski oligomerni silseskvioksani. Istraživan je njihov utjecaj na kinetiku izotermne razgradnje PEO-a. Aktivacijska energija, predeksponencijalni faktor i kinetički model izračunati su pomoću programa Netzsch Thermokinetics Professional. Utvrđeno je da se proces izotermne toplinske razgradnje odvija kroz jedan stupanj koji je najbolje opisan autokatalitičkim modelima.Poly(ethylene oxide) (PEO) and lithium salts based solid polymer electrolytes exhibit low ionic conductivity at the service temperatures, the main reason being the high crystallinity of PEO. Degree of crystallinity is often lowered by addition of nanoparticles, among them being a very interesting group known as polyhedral oligomeric silsesquioxanes (POSSs). In this work, the influence of POSS nanoparticles (methyl-, fluoro-, and chloro-phenil heptaisobutyl POSS) on kinetics of isothermal PEO degradation was investigated. Activation energy, pre-exponential factor, and kinetic model were determined using Netzsch Thermokinetics Professional program. It was found that the process of isothermal degradation occurs through one step, best described by autocatalytic models. According to Fig. 2 and Table 2, all investigated samples at 360, 370, and 380 °C after 60 min reach constant mass plateau with residual mass (mf) 3–7 %. In this temperature range, degradation of both PEO and POSSs occur. Before starting the kinetic analysis, the time necessary to gain isothermal conditions was subtracted. Activation energy (E) and pre-exponential factor (A) calculated using linear regression (LR), as well as the kinetic model of thermal degradation f(α) are summarised in Table 4. Activation energies of PEO/POSS 1, PEO/POSS 3 i PEO/POSS 5 samples are similar to those of PEO. The highest and lowest value of activation energy for PEO/POSS 4 and PEO/POSS 2 samples, respectively, is the result of their inherent thermal stability. Dependence of activation energy on conversion is of the same shape for all samples, implying the same mechanism of thermal degradation. DTG curves exhibit one degradation step only. Results of F-test (Table 3) indicate that extended Prout-Tompkins model as well as other autocatalytic models are statistically the best for description of the isothermal degradation of PEO and PEO/POSS composites.
rrep
6.525
NaslovKiosk des Sultans Abdul Medjid = Chiosco del Sultano Abdul Medjid / [Christian] Steinicken [prema fotografiji] Robertsona.
Impresum[Trst] : Österreichischer Lloyd (Trst), [1857.-1858.]. ([Trst] : Österreichischer Lloyd)
Materijalni opis1 grafika : nadorez ; 223 x 180 mm.
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6.526
NaslovKirche des Heil Antonius / T. [Thomas] Phillibrown [prema Eduardu Gurku].
Impresum[S.l.] : Hartleben’s Verlag, [1840.]. ([s.l.] Black & Armstrong)
Materijalni opis1 grafika : nadorez ; list 142 x 231 mm.
rrep
6.527
NaslovKirche des Heil Antonius / T. [Thomas] Phillibrown [prema Eduardu Gurku].
Impresum[S.l.] : Hartleben’s Verlag, [1840.]. ([s.l.] Black & Armstrong)
Materijalni opis1 grafika : nadorez ; list 142 x 231 mm.
rrep
6.528
NaslovKirchenstuhl in Brarhatir / M.[Martin] Pilar.
Impresum1885.
Materijalni opis1 crtež : tuš ; 670 x 460 mm.
rrep
6.529
NaslovKirche St. Mathias, Trier.
Impresum[S. l.] : [s. n.], [između 1800. i 1900].
Materijalni opis1 grafika : nadorez ; 123 x 141 mm.
rrep
6.530
16.634 (6.521-6.530)