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Qianling Cui, A. Yashchenok, Lu Zhang, Lidong Li, A. Masic, G. Wienskol, H. Möhwald, M. Bargheer

Herein, a facile method is presented to integrate large gold nanoflowers (∼80 nm) and small gold nanoparticles (2-4 nm) into a single entity, exhibiting both surface-enhanced Raman scattering (SERS) and catalytic activity. The as-prepared gold nanoflowers were coated by a gelatin layer, in which the gold precursor was adsorbed and in situ reduced into small gold nanoparticles. The thickness of the gelatin shell is controlled to less than 10 nm, ensuring that the small gold nanoparticles are still in a SERS-active range of the inner Au core. Therefore, the reaction catalyzed by these nanocomposites can be monitored in situ using label-free SERS spectroscopy. In addition, these bifunctional nanocomposites are also attractive candidates for application in SERS monitoring of bioreactions because of their excellent biocompatibility.

By using the KAM theory we investigate the stability of equilibrium solutions of the Gumowski-Mira equation: x n+1 = (2ax n)/(1 + x n 2) − x n−1, n = 0,1,…, where x −1, x 0 ∈ (−∞, ∞), and we obtain the Birkhoff normal forms for this equation for different equilibrium solutions.

B. Pavelić, M. Katunarić, S. Šegović, Maja Cimas Karadole, D. Katanec, Aida Šaban, Ivan Puhar

A. Huremovic, M. Hadzialic

In this paper we analyze delay and jitter in networks with traffic modelled as Interrupted Poisson process (IPP), and relatively small traffic loads. In one-node analysis, we estimate the probability for delay bounds violation, and we obtain expression for the jitter, with respect to phase probabilities, traffic load, and tagged traffic share in aggregate traffic flow. We also analyze delay and jitter for simple tandem network, where we propose a model for endto- end jitter. Our research shows how end-to end jitter is conditioned with phase probabilities of the incoming process, and we determine the nature of that correlation. Finally, we estimate the probability for end-to-end delay bounds violation, with respect to the jitter occurring on network nodes. Our propositions lead to some fast-to-compute approximations for the limit cases, which we propose as useful in evaluation of QoS constraints for real IP traffic

Aims: HMF (5-hydroxymethylfurfural) is considered an important quality parameter for honey. Elevated concentrations of HMF in honey provide an indication of origin, storage in poor conditions or age of honey. The objectives of this study were to investigate the effect of aging and botanical origin of honey on the HMF content in it, as well as to analyze the relationship between the content of HMF and fructose/glucose ratio. Study Design: In this paper, the HMF levels in different botanical origins of sixty bee honeys from Bosnia and Herzegovina (Acacia: Robinia pseudoacacia, meadow, chestnut: varii, mountain) were analysed; the influence of ageing on HMF formation was also investigated. Place and Duration of Study: Department of Chemistry, University in Tuzla, between January 2011 and Mart 2011. Methodology: Determination of HMF content was done by spectrophotometric White method. Content analysis of fructose and glucose in honey samples was performed using the HPLC. Results: Concentration of HMF in analyzed honey samples ranged from 0.28 mg/kg to 207.45 mg/kg. The HMF formation was correlated with botanical origin, age of honey and fructose/glucose ratio. Samples of 4 year old honey contains on average 52.44% higher Original Research Article Kesic et al.; JSRR, Article no. JSRR.2014.004 1058 HMF than fresh honey samples. These results clearly show that longer storage of honey increases the concentration of HMF. In addition, honey exposure to high temperatures affects content of HMF, which catalyzes the dehydration of fructose to form new quantities of HMF. The formation of HMF and its concentration in honey also depends on the botanical origin of honey. Samples of acacia honey showed the highest average content of HMF. The data obtained were statistically elaborated. Conclusion: Botanical origin, high temperature and storage significantly affect the content of HMF in honey. There is a negative correlation between the F/G ratio and HMF content in analyzed honey samples.

A. Kesić, Zorica Hod

This paper presents the results of physico-chemical parameters and heavy metals (Cu, Zn, Pb and Cd) contents in water sources of public supply of Tuzla and the surrounding area, as alternative sources of water supply. The study area was divided into six (6) sampling sites and their respective position was detected using GPS device (MAGELLAN EXPLORIST 210). The heavy metals were determined using Atomic Absorption Spectrophotometry (AAS), While, the physico-chemical parameters (pH, electrical conductivity (EC), carbonate, total hardness, nitrate (NO3 -N), nitrite (NO2 -N), ammonia (NH3 -N), KMnO4 and chlorides were determined using standard methods. The heavy metal contents: Cu (1-6 �g/L) and Zn (1-2 �g/L). Pb was only detected Simin Han well water at 2 �g/L. Cd was below detection limits in all samples. The levels of Zn, Cu, Cd and Pb in Tuzla and its surrounding alternative drinking sources are within the permissible limits according to the Regulations on the safety of drinking water of Bosnia and

Aims: This study explores the total quantity of sulfur secondary metabolites in the plant organs of garlic and ramsons, the content of total phenol and their correlation to the antioxidant capacity (AOC). There are different reports about correlation of secondary

Aims: Study investigates relation of sulfur compounds content in garlic and different type of manures that were used for rearing of this vegetable. Measured parameter was total sulfur which could be a valid parameter of content of aromatic and medicinal sulfur compounds in garlic (alliin etc.). Study Design: Quality of garlic mainly depends from content of sulfur compounds, there are articles related to influence of mineral fertilizer on the quality of garlic bulbs but effect of manures hasn’t been enough investigated. This research should give an estimation of effect of some manures on the quantity of sulfur compounds in garlic.

Contact lenses suffer from two limitations: low oxygen permeability and deposition of protein and lipids. In order to prevent bioadhesion, surface must be completely inert to all biological reactions. To achieve this, surface properties must be tailored. Also, to improve comfort, surface must be highly wettable and lubricous. In this paper the surface of silicone contact lenses was modified by plasma induced copolymerization of acrylic acid. A wettable surface was generated and in addition carboxyl groups that were created on the surface provided an ideal reactive platform for subsequent grafting of polyethylene glycol. Each surface modification step was analysed by XPS and contact angle measurements. Lysozyme adsorption on modified silicone contact lenses was analysed by surface-MALDI-ToF-MS and XPS. After incubation with lysozyme, surface-MALDI-TOF-MS and XPS analysis showed a reduction of adsorbed lysozyme on hydrogel modified contact lenses. Surface modification of silicone with PEG is a method for reduction of protein adsorption on contact lenses.

Eight samples of iron slag and two metallic artefacts from two Early Iron Age sites in central Bosnia and Herzegovina, ��olaci and Pod, were analysed using chemical instrumental methods. Atomic absorption spectrometry was applied to determine major (Fe, Al,Ca, Na, Mg, K and Mn) and trace elements (Cr, Cu, Co, Ni and Zn), while gravimetric method and molecular visible spectrometry were applied to determine Si and Ti, respectively. Infrared spectrum of selected samples was recorded during different phases ofanalysis and the results show that the primary ore was hematite. Results also indicate that residents from both sites, which are adjacent, used the same ore source. Low values of Ca, whose compounds are used as flux in later stages of the processing of iron ore, show that the processing of iron at the study sites was in the beginning stage of its development.Based on the obtained results, metallic artefacts found at the site ��olaci probably came from site Pod. Graphical presentation of the content relation ship between the selected metal oxides in the slag was preformed to present differences between samples from two sites. Analysis of trace elements in the analysed slags confirmed that they originate from Early Iron Age.

Majda Srabović, Melita Poljakovic, E. Pehlić

Aims: An important property of micelles with particular significance in pharmacy is their ability to increase the solubility of poorly soluble drugs in water thus increasing their bioavailability. It was of interest to increase the solubility of carbamazepine (CBZ) in aqueous media. Therefore, solubilization of carbamazepine (CBZ) in variety of surfactants was investigated. Study Design: In this work the solubilization of carbamazepine (CBZ) was studied in micellar solutions of different anionic and cationic surfactants.

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