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121.
122.
Milica Jovanovic Veljko Jeremic Gordana Savic Milica Bulajic Milan Martic 《Scientometrics》2012,93(2):319-327
The aim of this paper is to present new ideas in evaluating Shanghai University??s Academic Ranking of World Universities (ARWU). In particular, this paper shall try to determine whether the normalization of data affects University ranks. In accordance with this, both the normalized and original (raw) data for each of the six variables has been obtained. Based on a sample containing the 54 US universities which are placed in the ARWU top 100, the statistical I-distance method was performed. The results showed great inconsistencies between university ranks obtained for the original and normalized data. These findings were then analyzed and the universities that had the greatest fluctuation in their ranks were noted. 相似文献
123.
Gvozden S. TasicSladjana P. Maslovara Dragana L. ZugicAleksandar D. Maksic Milica P. Marceta Kaninski 《International Journal of Hydrogen Energy》2011,36(18):11588-11595
Objective of this work was to investigate the electrocatalytic efficiency using quasi-potentiostatic, galvanostatic and impedance spectroscopy techniques of the Ni-Mo catalysts obtained by in situ electrodeposition in an alkaline, 6 M KOH, electrolyser. In accordance to our previous studies, synergetic effect is observed, with its maximum at industrial conditions (high temperature and current density). The Tafel slopes are around 120 mV and exchange current densities are close to 10−2 mA cm−2 (three orders of magnitude higher compared to the bulk Ni). Moreover, formed deposit possess high stability during prolonged electrolysis. Results are presented to show the Tafel slopes, the exchange current densities, the apparent energy of activation, the apparent electrochemical surface and the stability of in situ formed Ni-Mo catalyst. Results suggest to significant catalytic performance not only from the increase of the real surface area of electrodes, but also from the true catalytic effect. 相似文献
124.
Modification of hydrophilic polymer network to design a carrier for a poorly water-soluble substance
Maja D. Markovic Vesna V. Panic Sanja I. Seslija Pavle M. Spasojevic Vukasin Dj. Ugrinovic Nevenka M. Boskovic-Vragolovic Rada V. Pjanovic 《Polymer Engineering and Science》2020,60(10):2496-2510
pH sensitive, nontoxic, and biocompatible poly(methacrylic) acid (PMAA) based soft networks have been extensively used in the design of systems for targeted drug delivery. Still, their highly hydrophilic nature limits their potential to be used as a carrier of poorly water-soluble substances. With the aim to overcome this limitation, the present study details a new approach for modification of PMAA based carriers using two amphiphilic components: casein and liposomes. The FTIR analysis revealed structural features of each component as well as the synergetic effect that originated from the formation of specific interactions. Namely, hydrophobic interactions between the poorly water-soluble model drug (caffeine) and casein enabled caffeine encapsulation and controlled release, while addition of liposomes ensured better control of the release rate. The morphological properties of the carriers, swelling behavior, and release kinetics of caffeine were investigated depending on the variable synthesis parameters (neutralization degree of methacrylic acid, concentration of caffeine, presence/absence of liposomes) in two different media simulating the pH environment of human intestines and stomach. The data obtained from in vitro caffeine release were correlated and analyzed in detail using several mathematical models, indicating significant potential of investigated carriers for targeted delivery and controlled release of poorly water-soluble substances. 相似文献
125.
Milica M. Gvozdenović Branimir Z. Jugović Jasmina S. Stevanović Branimir Grgur Tomislav Lj. Trišović Zvonimir S. Jugović 《Synthetic Metals》2011,161(13-14):1313-1318
Electrochemical polymerization of polyaniline (PANI) coating on copper electrode was performed galvanostatically in the current density range between 0.50 and 1.25 mA cm?2, from aqueous solution of 0.3 mol dm?3 sodium benzoate and 0.2 mol dm?3 aniline. The corrosion behavior of PANI coated copper and copper electrode exposed to 0.5 mol dm?3 sodium chloride solution was investigated by potentiodynamic and electrochemical impedance spectroscopy techniques. It was observed that thin PANI (5 μm) coating had provided efficient protection (~96%) to copper in 0.5 mol dm?3 sodium chloride solution. Unusual initial impedance behavior to that normally observed with conventional organic coatings was attributed to dedoping of benzoate anions from the polymer coating. 相似文献
126.
The Hidden Information State model: A practical framework for POMDP-based spoken dialogue management
Steve Young Milica Gai Simon Keizer Franois Mairesse Jost Schatzmann Blaise Thomson Kai Yu 《Computer Speech and Language》2010,24(2):150-174
This paper explains how Partially Observable Markov Decision Processes (POMDPs) can provide a principled mathematical framework for modelling the inherent uncertainty in spoken dialogue systems. It briefly summarises the basic mathematics and explains why exact optimisation is intractable. It then describes in some detail a form of approximation called the Hidden Information State model which does scale and which can be used to build practical systems. A prototype HIS system for the tourist information domain is evaluated and compared with a baseline MDP system using both user simulations and a live user trial. The results give strong support to the central contention that the POMDP-based framework is both a tractable and powerful approach to building more robust spoken dialogue systems. 相似文献
127.
Vladimir M. Nikolic Gvozden S. Tasic Aleksandar D. Maksic Djordje P. Saponjic Snezana M. Miulovic Milica P. Marceta Kaninski 《International Journal of Hydrogen Energy》2010
This paper presents an attempt to make the alkaline electrolytic production of hydrogen more efficient by adding in situ activating compounds in ionic and complex form. Cobalt and tungsten based ionic activators (i.a.), added directly into the electrolyte during the electrolytic process, reduce energy requirements per mass unit of hydrogen produced for about 15%, compared to non-activated system, for a number of current densities in a wide temperature range. Energy saving is higher at higher temperatures and on higher current densities. Structural and morphological characteristic of deposit formed on the cathode during the electrolytic process reveal very interesting and unique pattern with highly developed surface area and uniform distribution of the pores. Obtained deposit also exhibit a long term stability. 相似文献
128.
Milica Milošević Marija Radoičić Zoran Šaponjić Tim Nunney Darka Marković Jovan Nedeljković Maja Radetić 《Journal of Materials Science》2013,48(16):5447-5455
This study discusses the possibility of in situ generation of Ag nanoparticles on polyester fabric by photoreduction of Ag+ ions with deposited TiO2 nanoparticles in the presence of amino acid alanine and methyl alcohol. The presence of TiO2/Ag nanoparticles on the polyester fiber surface was confirmed by XRD, XPS, and SEM analyses. Such nanocomposite textile material provides excellent antimicrobial activity against Gram-negative bacterium E. coli, Gram-positive bacterium S. aureus, and fungus C. albicans. Maximum microbial reduction was preserved even after ten washing cycles. In spite of satisfactory laundering durability, the release of silver occurred during washing. The leaching of silver was also present when the fabrics were exposed to artificial sweat at pH 5.5 and pH 8.0 for 24 h. In addition to excellent antimicrobial properties, TiO2/Ag nanoparticles imparted maximum UV protection to polyester fabrics. 相似文献
129.
Milica P. Marčeta Kaninski Mina M. SeovićSnežana M. Miulović Dragana L. ŽugićGvozden S. Tasić Đorđe P. Šaponjić 《International Journal of Hydrogen Energy》2013
Catalyst based on cobalt and chrome was investigated as cathode material for hydrogen production process via water electrolysis. Electrocatalytic efficiency of proposed system was studied using quasi-potentiostatic, galvanostatic and impedance spectroscopy techniques of the catalyst obtained by in situ electrodeposition in an alkaline, 6 M KOH, electrolyser. In accordance to our previous studies, synergetic effect of cobalt complex and chrome salt is observed, with its maximum at high temperatures and for high current densities (industrial conditions). The Tafel slopes were found to be around 120 mV and exchange current densities in the range of 10−3 mA cm−2 up to 10−2 mA cm−2. Results are presented to show the Tafel slopes, the exchange current densities, the apparent energy of activation and the apparent electrochemical surface of in situ formed Co–Cr catalyst. This study shows that catalytic performance of Co–Cr was achieved not only from the increase of the real surface area of electrodes, but also from the true catalytic effect. 相似文献
130.
Ivana Medigović Nataša Ristić Svetlana Trifunović Milica Manojlović‐Stojanoski Verica Milošević Dragan Žikić Nataša Nestorović 《Microscopy research and technique》2012,75(12):1691-1699
The effects of short‐term genistein exposure on ovarian folliculogenesis in immature rats were examined stereologically. To determine whether genistein acts as an estrogen agonist or antagonist, the results were compared with the effects of 17α‐ethynylestradiol. Immature female rats received 50 mg/kg/bw of genistein in dimethyl sulfoxide subcutaneously daily for three consecutive days from 18 to 20 days. The second group was injected with 1 μg/kg/bw of 17α‐ethynylestradiol in olive oil in the same schedule. Each group had a corresponding control. Genistein increased ovary and ovarian stroma volumes by 18.50% (P < 0.05) and 53.40% (P < 0.05), respectively, and changed the parenchyma to stroma ratio in favor of stroma. Genistein induced decreases in the number of primordial (by 17.23%; P < 0.05), primary (16.62%; P < 0.05), and secondary follicles (12.29%: P < 0.05), whereas the number of atretic secondary follicles increased (5.10‐fold; P < 0.05). The number of healthy large follicles was raised by 27.3% (P < 0.05), accompanied by 35.64% more atretic large follicles (P < 0.05). Similarly to genistein, estradiol changed the parenchyma to stroma ratio in favor of stroma, and reduced the number of primordial follicles, but the number of primary follicles was elevated. There were more healthy and atretic small and large follicles. In conclusion, genistein acted as an estrogen antagonist and had an inhibitory effect on the initial phase of folliculogenesis. In the other phases, genistein acted as an estrogen agonist, stimulating transition from the preantral to antral stage of folliculogenesis, and altering the ratio of follicular parenchyma and ovarian stroma in favor of stroma. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc. 相似文献