JIMP 2 Software as a teaching tool: Understanding orbitals using fenskee-hall method

Teaching molecular orbital concept to undergraduate students is known to be very challenging; analysis of examination data for undergraduate students reveals that they do not have a clear understanding of the concepts of atomic and molecular orbitals (Tsaparlis, 1997). Understanding of the orbital concept has been subject to considerable debate and research (Barradas-Solas and Sánchez Gómez, 2014). One of teaching strategies to deal with this problem is based on usage of different quantum chemical software to calculate shape, energy and to visualize molecular orbitals. The main downside of this approach is the fact that quantum chemical calculations are often very time-consuming, especially in the case of molecules that contain transition metal atoms. Fenske-Hall method is ab initio method mainly developed for molecular orbitals calculation of transition metal complexes and organometallic compounds (Hall and Fenske, 1972). It was shown that this method is very fast, and very accurate (results are similar to the results obtained by more rigorous and more time-consuming DFT methods). Here we present a series of computational laboratory exercises using Fenske-Hall method incorporated in Jimp2 software to calculate and visualize both atomic and molecular orbitals. Students will learn how to calculate energy and visualize molecular orbitals of simple molecules. Exercises provide deeper insight into relationship between atomic and molecular orbitals with special emphasis on calculation of contribution of atomic orbitals in particular molecular orbital. Using results of Fenske-Hall calculations, students will construct molecular-orbital diagrams for simple molecules

Lipidni profil i zdravstveni značaj najčešće konzumiranih rečnih i morskih riba u populaciji Srbije

Background/Aim. Dietary intake of n-3 long-chain polyun-saturated fatty acids (LC-PUFA) is important in prevention and treatment of different diseases. In general population, the average intake of n-3 LC-PUFA is often significantly lower than recom-mended levels. Fish lipids are rich sources of these fatty acids, of which the most important are eicosapentaenoic (20:5 n-3, EPA) and docosahexaenoic (22:6 n-3, DHA) fatty acids. This study was designed to determine and compare fat, fatty acids and lipid qual-ity indices in 10 commercial fish species available on the Serbian market, as well as relation between their price and nutritional val-ue. Methods. Freshwater fish originated from the Danube River in the Belgrade Region, while seawater fish were mostly from the Adriatic Sea. A gas chromatography method was used to define fatty acids in 40 fish samples after lipid extraction. Cost-minimization analysis was conducted to assess the economic util-ity. Results. Seawater fish had a significantly higher value of flash lipid quality compared to the freshwater fish (p < 0.05). Value of Background/Aim. Dietary intake of n-3 long-chain polyun-saturated fatty acids (LC-PUFA) is important in prevention and treatment of different diseases. In general population, the average intake of n-3 LC-PUFA is often significantly lower than recom-mended levels. Fish lipids are rich sources of these fatty acids, of which the most important are eicosapentaenoic (20:5 n-3, EPA) and docosahexaenoic (22:6 n-3, DHA) fatty acids. This study was designed to determine and compare fat, fatty acids and lipid qual-ity indices in 10 commercial fish species available on the Serbian market, as well as relation between their price and nutritional val-ue. Methods. Freshwater fish originated from the Danube River in the Belgrade Region, while seawater fish were mostly from the Adriatic Sea. A gas chromatography method was used to define fatty acids in 40 fish samples after lipid extraction. Cost-minimization analysis was conducted to assess the economic util-ity. Results. Seawater fish had a significantly higher value of flash lipid quality compared to the freshwater fish (p < 0.05). Value of Background/Aim. Dietary intake of n-3 long-chain polyun-saturated fatty acids (LC-PUFA) is important in prevention and treatment of different diseases. In general population, the average intake of n-3 LC-PUFA is often significantly lower than recom-mended levels. Fish lipids are rich sources of these fatty acids, of which the most important are eicosapentaenoic (20:5 n-3, EPA) and docosahexaenoic (22:6 n-3, DHA) fatty acids. This study was designed to determine and compare fat, fatty acids and lipid qual-ity indices in 10 commercial fish species available on the Serbian market, as well as relation between their price and nutritional val-ue. Methods. Freshwater fish originated from the Danube River in the Belgrade Region, while seawater fish were mostly from the Adriatic Sea. A gas chromatography method was used to define fatty acids in 40 fish samples after lipid extraction. Cost-minimization analysis was conducted to assess the economic util-ity. Results. Seawater fish had a significantly higher value of flash lipid quality compared to the freshwater fish (p < 0.05). Value of hypercholesterolaemic fatty acids (OFA) for the freshwater group was 18.70 (17.40‒21.30) while the seawater group had a similar range of values 18.90 (17.55‒22.75). Hypocholesterol-aemic fatty acids (DFA) also showed similar ranges for both groups: 68.80 (66‒70.20) for freshwater and 68.40 (64.85‒73.05) for seawater group. The ratio of DHA/EPA ranged from 1.8 for sardine samples and up to 10 for tuna samples, indicating that the amount of DHA in natural samples exceeds the amount of EPA in many cases. The values of ath-erogenic (AI) and thrombogenic index (TI) were lower than 1 for all analysed samples. Conclusion. Sardine and mackerel had the highest content of n-3 LC-PUFA and presented the least expensive sources of EPA and DHA. The low values of AI and TI obtained from studied fish indicate its benefits from a health point of view.Uvod/Cilj. Unos n-3 polinezasićenih masnih kiselina (PMK) je od velike važnosti u prevenciji i tretmanu različitih oboljen-ja. Generalno posmatrajući, prosečan unos n-3 PMK je obično značajno niži od utvrđenih preporuka. Lipidi riba sadrže masne kiseline n-3 serije od kojih su najvažnije ei-kozapentaenska (20:5 n-3, EPA) i dokozaheksaenska (20:6 n-3, DHA) masna kiselina. Cilj ove studije bio je odrediti i uporediti lipidni profil i lipidne indekse u 10 različitih vrsta riba dostupnih na tržištu Srbije. Takođe, određen je odnos cene i nutritivne vrednosti odabranih vrsta. Metode. Ispiti-vane su rečne ribe Dunava iz Beogradskog regiona, dok su morske ribe uglavnom vodile poreklo iz Jadranskog mora. Gasna hromatografija sa jonskim detektorom je korišćena za određivanje masnih kiselina u 40 uzoraka nakon lipidne ekstrakcije. Cost-minimization analiza je korišćena za procenu ekonomske koristi. Rezultati. Morske ribe su imale značajno veće vrednosti za parametar flash lipid quality u odnosu na rečne ribe (p < 0,05). Vrednosti hiperholesterolemijskih mas-nih kiselina za grupu rečnih riba [18,70 (17,40‒21,30)] bile su slične vrednostima dobijenim za morske ribe [18,90 (17,55‒22,75)]. Hipoholesterolemijske masne kiseline su takođe pokazale sličan raspon vrednosti za rečne [68.80 (66–70.20)] i morske ribe [68.40 (64.85–73.05)]. Odnos DHA/EPA kretao se od 1,8 za uzorke sardine, do 10 za uzorke tune, što potvrđuje činjenicu da DHA prevazilazi vrednosti za EPA u svim ispitivanim uzorcima. Vrednosti za aterogeni i trombogeni indeks su bile niže od 1 za sve ana-lizirane uzorke. Zaključak. Sardine i skuša su imale najveći sadržaj n-3 PMK i predstavljale su najekonomičniji izvor EPA i DHA. Niske vrednosti za aterogeni i trombogeni in-deks ukazuju na potencijalno povoljan zdravstveni efekat ispitivanih vrsta

Supplementary material for the article: Malenov, D. P.; Antonijević, I. S.; Hall, M. B.; Zarić, S. D. Stacking of Cyclopentadienyl Organometallic Sandwich and Half-Sandwich Compounds. Strong Interactions of Sandwiches at Large Offsets. CrystEngComm 2018, 20 (31), 4506–4514. https://doi.org/10.1039/c8ce00597d

Supplementary material for: [https://doi.org/10.1039/c8ce00597d]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2202

Supplementary data for the article: Antonijević, I. S.; Janjić, G. V.; Milčić, M. K.; Zarić, S. D. Preferred Geometries and Energies of Sulfur-Sulfur Interactions in Crystal Structures. Crystal Growth and Design 2016, 16 (2), 632–639. https://doi.org/10.1021/acs.cgd.5b01058

Supplementary material for: [https://doi.org/10.1021/acs.cgd.5b01058]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2042]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3596

Development of low carbon and energy-efficient geopolymer-based paving blocks

The development of energy-efficient and low-carbon geopolymer-based paving blocks made from waste, as an environmental-friendly material, was evaluated. Ground concrete (GC) and solid brick (SB) powder, as the representatives of construction and demolition waste (C&DW), with the addition of fly ash (FA) and silica fume (SF), were used. Waste samples were characterized in terms of surface functional groups and radioactivity. The FT-IR spectra showed the required amorphous or semi-crystalline alumino-silicate structure. The gamma spectrometry confirmed waste samples' radiological safety. Hardened geopolymer samples were subjected to physical-mechanical investigation comprising of density, water content, compressive and flexural strengths determination. Based on strength characteristics, the three best prototype mixtures were selected and subjected to further compressive strength determination and durability assessment. Prototype sample SBFASFp1, with a compressive strength of 18.7 MPa, was shown the highest value of all samples, almost the same as the corresponding SBFASF1 sample. Freeze-thaw and the subsequent carbonation tests, as durability indicators, showed that the SBFASF1 sample had the slightest strength decrease, making it most durable in these conditions. These satisfactory test results showed the favorable effects of alternatives to cementitious materials, encouraging their utilization and contributing to the sustainability of the construction sector

Does the Increase in the Number of Registered Patents Affect Economic Growth? Evidence from Romania and Bulgaria

The goal of this paper is to determine whether the increase in the number of registered patents per million inhabitants, as a measure of market verification of the results of R&D activities, affects economic growth and the increase in the country's innovation index. The empirical research covered two countries - Romania and Bulgaria. Given that the main task of the research was to accurately measure the investigated phenomena and discover the connection between them, the analysis was based on a quantitative research design. The analysis used secondary data from the international databases of the World Bank and World Intellectual Property Organization, covering the period from 2008 to 2018. The results of the empirical research showed that no correlations were found, which means that in the cases of Romania and Bulgaria, there is no dependence between the increase in the number of registered patents per million inhabitants and the growth of the innovation index and GDP per capita

Theoretical Foundation and Actuality of the Concept Education through Art

This paper is on the relation between art and education through the concept Education through Art, from the perspective of progressive pedagogy. Theoretical foundation is analysed through the theories of John Dewey and Herbert Read who stressed that art should be experienced, not only because of its prefect value, but because of its pedagogical potential (for the purpose of recreating and reconstructing experience). Elliot Eisner contribution is also analysed, who discussing the significance of art, points out at the cognitive aspect of art in education. With his work, pedagogy gets steady alternative model in relation to the contemporary school which is intellectually oriented and in which pedagogical work in school is focused on verbal and mathematical proficiencies. Progressive pedagogy opposes traditional formalism in education, which is organised in advance by the subject syllabi, and teaching to the test. It promotes desirable interdisciplinary organisation of teaching, with the cross curricular activities, transforming the learning environment in this way. In the paper, we discussed implications for the praxis of theoretical concept, which directs the work at school towards the whole development of personality and it affirms realisation of creative activities through play and research integrating art in the process of learning

Application of composite construction and demolition debris in heavy metals removal from industrial wastewater

The utilization of construction and demolition debris in industrial wastewater treatment by sorption of Co2+ and Ni2+ ions was investigated. Selected waste composites are cost-effective and locally available, still their sorption character-istics and application are not sufficiently investigated. The samples of concrete, facade, ceramic materials, and asphalt were characterized in terms of mineral and surface composition, radioactivity, and stability at different pH values, as well as pH values of suspension and filtrate and electrical conductivity of the fil-trate. The sorption capacities were determined in batch experimental conditions in one and multi-component solutions. Characterization showed different crystal structures and mineralogical compositions of components. The results of gamma spectrometry confirmed the radiological safety of samples. Based on stability testing results, waste materials are suitable for further utilization and do not pose any risk to the environment. The overall sorption results suggested that cement-based materials, in addition to high affinity for the tested ions, represent a sorbent that binds contaminants firmly enough, reduces their mobility and bioa-vailability, and are suitable for removing Co2+ and Ni2+ ions from wastewaters

Radon exhalation rate of some building materials common in Serbia

It is well-known that radon is the second important human carcinogen for lung cancer, after smoking. The major sources of indoor radon concentrations are soil and building material. Under certain conditions, a dose received from the inhalation of radon and its progenies can be higher than a dose received from the external exposure due to radium concentration in building materials. In this contribution, the results of the radon and thoron exhalation rate measurement from 9 commonly used building materials are reported. Exhalation rate measurements were performed with accumulation chamber method using active device for measurement of radon concentration. © 2019 RAD Association. All rights reserved.Conference of 6th International Conference on Radiation and Applications in Various Fields of Research, RAD 2018 ; Conference Date: 18 June 2018 Through 22 June 2018; Conference Code:14955