41. Improved photocatalytic activity of SnO[sub]2-TiO[sub]2 nanocomposite thin films prepared by low-temperature sol-gel methodKsenija Maver, Iztok Arčon, Mattia Fanetti, Samar Al Jitan, Giovanni Palmisano, Matjaž Valant, Urška Lavrenčič Štangar, 2021, izvirni znanstveni članek Opis: The objective of this research was to investigate how the photocatalytic activity of pure TiO2 can be improved by
SnO2 modification. Different molar ratios of tin to titanium were prepared. The correlation between tin concentration
and structural properties was investigated to explain the mechanism of photocatalytic efficiency and
to optimize the synthesis conditions to obtain enhanced activity of the SnO2-modified TiO2 photocatalysts under
UV-irradiation. The SnO2-modified TiO2 photocatalysts were prepared by a low-temperature sol-gel method
based on organic tin and titanium precursors. The precursors underwent sol-gel reactions separately to form
SnO2-TiO2 sol. The sol-gels were deposited on a glass substrate by a dip-coating technique and dried at 150 ◦C to
obtain the photocatalysts in the form of a thin film. To test the thermal stability of the material, an additional set
of photocatalysts was prepared by calcining the dried samples in air at 500 ◦C. The photocatalytic activity of the
samples was determined by measuring the degradation rate of an azo dye. An increase of up to 30% in the
photocatalytic activity of the air-dried samples was obtained when the TiO2 was modified with the SnO2 in a
concentration range of 0.1–1 mol.%. At higher SnO2 loadings, the photocatalytic activity of the photocatalyst
was reduced compared to the unmodified TiO2. The calcined samples showed an overall reduced photocatalytic
activity compared to the air-dried samples. Various characterization techniques (UV-Vis, XRD, N2-physisorption,
TEM, EDX, SEM, XAS and photoelectrochemical characterization) were used to explain the mechanism for the
enhanced and hindered photocatalytic performances of the SnO2-modified TiO2 photocatalysts. The results
showed that the nanocrystalline cassiterite SnO2 is attached to the TiO2 nanocrystallites through the Sn-O-Ti
bonds. In this way, the coupling of two semiconductors, SnO2 and TiO2, was demonstrated. Compared to
single-phase photocatalysts, the coupling of semiconductors has a beneficial effect on the separation of charge
carriers, which prolongs their lifetime for accessibility to participate in the redox reactions. The maximum increase
in activity of the thin films was achieved in the low concentration range (0.1–1 mol.%), which means that
an optimal ratio and contact of the two phases is achieved for the given physical parameters such as particle size,
shape and specific surface area of the catalyst.
Ključne besede: photocatalytic activity, Sn-modified TiO2, low-temperature, thin films, XAS analysis
Objavljeno v RUNG: 05.07.2021; Ogledov: 2526; Prenosov: 0
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42. Vati, Kedumetse (PRC-JTU); Székelyhidi, László (H-LAJO-IM) Exponential monomials on hypergroup joins. (English summary) Miskolc Math. Notes 21 (2020), no. 1, 463-472 : [review]Irina Elena Cristea, 2021, recenzija, prikaz knjige, kritika Ključne besede: spectral analysis, hypergroup join, exponential polynomial
Objavljeno v RUNG: 02.07.2021; Ogledov: 2082; Prenosov: 14
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43. Analiza utjecaja zagađenja zraka na zdravlje ljudi u Bosni i Hercegovini : predavanje na 2. Studentskom kongresu okolišnog zdravlja s medjunarodnim sudjelovanjem, Rijeka, Hrvatska, 6. 6. 2018Katja Džepina, 2018, prispevek na konferenci brez natisa Ključne besede: PM2.5, Ozone, Sarajevo, Tuzla, Zenica, Bosnia and Herzegovina, US EPA BenMAP, Cost-Benefit Analysis, Adverse health effects
Objavljeno v RUNG: 29.05.2021; Ogledov: 2286; Prenosov: 0
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44. Quality control of purified proteins to improve data quality and reproducibility: results from a large-scale surveyNick Berrow, Ario De Marco, Mario Lebendiker, Maria Garcia-Alai, Stefan H. Knauer, Blanca Lopez-Mendez, Andre Matagne, Annabel Parret, Kim Remans, Stephan Uebel, Bertrand Raynal, 2021, izvirni znanstveni članek Ključne besede: protein quality, biophysical analysis, protein aggregates
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45. Long-term ozone data analysisVjera Butković, Tomislav Cvitaš, Katja Džepina, Nenad Kezele, Leo Klasinc, 2002, izvirni znanstveni članek Opis: Various approaches to the analysis of 10-year continuous ozone monitoring from the EUROTRAC-TOR network station Puntijarka near Zagreb are reported. The site has a rural character (45.90degrees N; 15.97degrees E, 980 m a.s.l.) and is representative of the lower troposphere of a wider region. Mean hourly ozone volume fractions measured from 1990-1999, autocorrelation plots for all data and for data for summer periods (May-Sep.), box and whiskers representations of diurnal variations during winter (Nov.-March) and summer periods, mean monthly values and 12-month moving averages, and the Fourier transform of the complete set of 94,248 hourly mean ozone volume fractions are discussed. The data show no increase, or possibly a slight decrease, of the ozone volume fraction toward the end of the decade.
Ključne besede: long term ozone data, fourier analysis, ozone trend analysis, Puntijarka field station
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46. Carcinogenic organic content of particulate matter at urban locations with different pollution sourcesGordana Pehnec, Ivana Jakovljević, Ranka Godec, Zdravka Sever Štrukil, Sabina Žero, Jasna Huremović, Katja Džepina, 2020, izvirni znanstveni članek Opis: Polycyclic aromatic hydrocarbons (PAHs) are compounds known for their adverse effects on human health. Many of them are proven carcinogens, especially those with 5 and 6 aromatic rings, which under normal tropospheric conditions are found in the particle-phase. Benzo(a)pyrene (BaP) is often measured as their general representative. Sarajevo, the capital of Bosnia and Herzegovina, is among the European cities with the poorest air quality. However, in Sarajevo PAHs are neither routinely measured within the air quality monitoring network nor have been a subject of extended, continuous field studies during the most polluted cold periods of the year. The capital of Croatia, Zagreb, is located approximately 300 km air distance north-west from Sarajevo.
PAH mass concentrations in Zagreb have been measured continuously since 1994 within air quality monitoring networks. During winter 2017/2018, the SAFICA project (Sarajevo Canton Winter Field Campaign 2018) was carried out in order to characterize the chemical composition of organic and inorganic aerosol in the Sarajevo Canton. This paper presents the results of PAH measurements in the cities of Sarajevo and Zagreb at one urban
location per city. Daily (24 h), continuous samples of PM10 (particulate matter with aerodynamic diameters
≤10 μm) were collected during heating season, from December 27, 2017 to February 27, 2018. Mass concentrations of eleven particle-phase PAHs in Sarajevo and Zagreb from filter samples collected during the same period were compared. The average BaP ambient mass concentrations in Sarajevo and Zagreb were 6.93 ng m−3 and 3.11 ng m−3, respectively. The contribution of BaP to the total PAH mass concentration was similar at both locations (11%). However, much higher contributions of particle-phase fluoranthene and pyrene were found in Sarajevo. Contributions of individual PAH, diagnostic ratios and factor analysis indicate that combustion of gasoline and diesel from vehicle traffic are a potential source of PAHs at both locations, as well as combustion of other liquid fossil fuels (petroleum and fuel oil). Wood burning was occasionally indicated as a PAH emission source in
Zagreb, while in Sarajevo the contribution of PAHs from wood and coal combustion was more evident. Calculated value for total carcinogenic potency (TCP) of PAHs, which was estimated using toxic equivalence factors from the literature, in PM10 samples collected in Sarajevo was more than twice higher than in Zagreb (10.6 ng m−3 and 4.7 ng m−3, respectively). BaP had the highest contribution to the TCP at both locations (69 and 67%).
Ključne besede: carcinogenic potency, diagnostic ratio, factor analysis, PM10, polycyclic aromatic hydrocarbons
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47. Technological and analytical review of contact tracing apps for COVID-19 managementRajan Gupta, Gaurav Pandey, Poonam Chaudhary, Saibal K. Pal, 2021, izvirni znanstveni članek Opis: Role of technology is improving for COVID-19 management all around the world. Usage of mobile applications, web applications, cloud computing, and related technologies have helped many public administrators worldwide manage the current pandemic. Contact tracing applications are such mobile app solutions that are used by more than 100 countries today. This study presents a structured research review-based framework related to multiple contact tracing applications. The various components of the framework are related to technological working, design architecture, and feature analysis of the applications, along with the analysis of the acceptance of such applications worldwide. Also, components focusing on the security features and analysis of these applications based on Data Privacy, Security Vetting, and different attacks have been included in the research framework. Many applications are yet to explore the analytical capabilities of the data generated through contact tracing. The various use-cases identified for these applications are detecting positive case probability, identifying a containment zone in the country, finding regional hotspots, monitoring public events & gatherings, identifying sensitive routes, and allocating resources in various regions during the pandemic. This study will act as a guide for the users researching contact tracings applications using the proposed four-layered framework for their app assessment.
Ključne besede: novel corona virus, location technology, contact tracing applications, Aarogya Setu App, data science, data analysis
Objavljeno v RUNG: 02.04.2021; Ogledov: 1976; Prenosov: 0
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48. A novel lightweight encryption scheme for multimedia dataRajan Gupta, Saibal K. Pal, Neeharika Chaudhary, 2014, izvirni znanstveni članek Opis: The usage of Multimedia data has increased by many folds in recent years. And with so many different types of devices available to access the data, it becomes imperative to protect its sanctity. In this paper, a novel lightweight encryption scheme using a secret key has been proposed for multimedia data especially Videos. Chaos based maps has been used to provide an apt level of confusion and diffusion process at different levels of Video Processing. Proposed technique has a high encryption rate and performs well even with the videos with excessive
redundant data. Security Analysis has been performed to validate the high security features against different types of Statistical and Differential attacks and helps to prove the effectiveness of proposed system.
Ključne besede: chaotic maps, lightweight schemes, multimedia encryption, security analysis
Objavljeno v RUNG: 01.04.2021; Ogledov: 1920; Prenosov: 10
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49. Design and analysis of new shuffle encryption schemes for multimediaRajan Gupta, Ankur Aggarwal, Saibal K. Pal, 2012, izvirni znanstveni članek Opis: Securing the contents of visual data and multimedia requires specific design consideration for use in different applications. The major issue with this type of data has been occurrence of redundancy, at various places particularly in images, which makes data values repetitive at several places. The focus of this paper is on design of new shuffling schemes that can efficiently destroy redundancy in the visual data ensuring its secured transmission and distribution over public networks. Different variants of these shuffling schemes will be used as pre-processing schemes on multimedia data values especially in light weight devices using images. Standard as well as chaotic permutation and substitution schemes together with S-box rotation have been used to shuffle and map the plain data into random uncorrelated values via various variants of the presented schemes. For further improving the security, the processed data is encrypted using a computationally fast algorithm in its normal mode of operation. Security analysis using different types of images show that the proposed schemes satisfy the parameters required for securing visual contents even with very high redundancy.
Ključne besede: multimedia security, shuffle, S-box, chaotic encryption, security analysis
Objavljeno v RUNG: 01.04.2021; Ogledov: 1973; Prenosov: 0
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50. Internet traffic surveillance & network monitoring in India : case study of NETRARajan Gupta, Sunil K. Muttoo, 2016, izvirni znanstveni članek Opis: Internet traffic surveillance is gaining importance in today’s digital world. Lots of international agencies are putting in efforts to monitor the network around their countries to see suspicious activities and illegal or illegitimate transmission of messages. India, being a center of attraction for terrorist activities, is also working towards the development of such surveillance systems. NETRA or Network Traffic Analysis is one such effort being taken by the Indian Government to filter suspicious keywords from messages in the network. But is it good enough to be used at the highest level for security analysis or does the system design needs to be improved as compared to other similar systems around the world; this question is answered through this study. The comparison of NETRA is done against Dish Fire, Prism, and Echelon. The design of the NETRA scheme and implementation level analysis of the system shows few weaknesses like limited memory options, limited channels for monitoring, pre-set filters, ignoring big data demands, security concerns, social values breach and ignoring ethical issues. These can be covered through alternate options which can improve the existing system. The Inclusion of self-similarity models, Self-Configuring Network Monitoring, and smart monitoring through early intrusion detections can be embedded in the architecture of existing surveillance system to give it more depth and make it more robust.
Ključne besede: cyber attacks, NETRA, network monitoring, network traffic analysis, surveillance system, spy system
Objavljeno v RUNG: 01.04.2021; Ogledov: 1936; Prenosov: 55
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