SCIDAR - Дигитална архива Универзитета у Крагујевцу
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PHENOLIC CONTENT AND ANTIOXIDANT PROPERTIES OF SOME NATURAL COSMETIC CREAMS WITH PLANT-DERIVED INGREDIENTS AVAILABLE ON THE SERBIAN MARKET
Full text linkThe main goal of this study is to determine some properties of natural cosmetic creams that may have benefits for the skin. Five different cosmetic cream formulations with ingredients of botanical origin such as plant extracts, plant oil macerates, or essential oils were subjected to determine their phenolic content and antioxidant activity using the DPPH method. Total phenolic compounds were detected in all tested samples in the range of 1.7 to 0.2 mg GA/g but some samples did not contain flavonoids and did not possess antioxidant activity. The highest phenolic content and the strongest antioxidant activity were recorded for samples with the highest number of ingredients of plant origin.Publishe
OPTIMIZATION OF ULTRASONIC-ASSISTED EXTRACTION OF PHENOLIC COMPOUNDS FROM SALVIA VERTICILLATA L. ROOT USING RESPONSE SURFACE METHODOLOGY
Full text linkThis study aimed to optimize the conditions of ultrasonic-assisted extraction to obtain the highest content of phenolic compounds from Salvia verticillata L. root using response surface methodology. RSM was applied to maximize total phenolic content from Salvia verticillata L. root while minimizing operative temperature, ethanol composition, the solvent-to-solid ratio, and time. The obtained optimal conditions were ethanol percentage of 20 %, solvent-to-solid ratio of 40 mL g-1 Salvia verticillata L. is (lilac sage) belongs to the genus Salvia (Lamiaceae). Salvia plants have applications in the food, aromatic, and pharmaceutical , a temperature of 33.68 °C, and a time of extraction of 10 minutes. Obtained optimal conditions could be used for further investigation of the biological activities of Salvia verticillata L. and related plant species.Publishe
ENERGETSKE PERFORMANSE INFILTRIRANIH I ELEVACIONIH ZEMUNICA NA PODRUČJU GRADA KRAGUJEVCA – NUMERIČKO ISTRAŽIVANJE
No full textU ovom radu istražen je energetski potencijal različitih tipova savremenih zemunica, tokom sedmomesečnog vremenskog perioda (od 1. oktobra do 30. aprila), u cilju dostizanja održivog razvoja. Predmet istraživanja je jednospratna stambena zgrada (ukupne neto površine 102,5 m2), namenjena boravku četvoročlane porodice, locirana na području grada Kragujevca (centralna Srbija). Sistem grejanja formiraju toplotna pumpa tipa zemlja-voda, geotermalne vertikalne sonde, podni panelni grejači i dve cirkulacione pumpe. Numeričkom analizom (koristeći softver EnergyPlus) istražena su četiri tipa infiltriranih, kao i jedna elevaciona zemunica. Energetske performanse svih pomenutih zemunica upoređene su sa energetskim performansama klasične nadzemne zgrade. Sve zgrade su istih geometrijskih, građevinskih i termotehničkih performansi. Rezultati istraživanja pokazali su da se, u infiltriranim zemunicama, godišnja potrošnja finalne (električne) energije može redukovati za 2,53−21,64% (zavisno od broja spoljašnjih građevinskih elemenata u direktnom kontaktu sa zemljištem). Savremena arhitektura ipak treba biti usmerena na razvoj elevacionih zemunica, jer se u njima godišnja potrošnja finalne (električne) energije za grejanje može redukovati za preko 40%
Comparative Analysis of the Application of Different Metaheuristic Methods for Determining the Coefficients of Empirical Models for Determining Sound Absorption
Full text linkAVMS 2023Metaheuristics are widely used in various fields due to their ability to solve complicated optimization problems. In acoustics, it is possible to apply metaheuristics to determine the optimal values of coefficients in empirical models of acoustic impedance. In this paper, different metaheuristic approaches (i.e. gray wolf optimization algorithm, marine predator algorithm, beluga whale optimization, sand cat swarm optimization) are presented for solving the above problem. They are based on different biological phenomena and with these methods no experience is required in determining the initial values of the variables as it is possible to set a wide range for the initial values of the variables. The applied methods provide a satisfactory prediction of the sound absorption coefficient of open-cell polyurethane foam, compared to the experimental results obtained in an impedance tube. The paper provides a comparative analysis of recent metaheuristics: gray wolf optimization algorithm, beluga whale optimization algorithm, marine predator algorithm and sand cat algorithm.The Ministry of Education, Science and Technological Development of the Republic of Serbia, contract record number: 451-03-47/2023-01/200108https://link.springer.com/chapter/10.1007/978-3-031-48087-4_11Author's versio
Analytical and numerical analysis of the modified 2D arc-star-shaped structure with negative Poisson's ratio
Full text linkThe Poisson’s ratio represents one of the very important characteristics of mechanical metamaterials. Thanks to additive manufacturing, it is now much simpler to create structures for the study of Poisson’s ratio. Particularly, for research purposes, re-entrant structures are of interest as they can exhibit negative values of Poisson’s ratio. Due to their capabilities, such structures find extensive applications across various industries. The modified arc-star-shaped (m2D-AS) has been studied analytically and numerically, and the negative Poisson’s ratio (NPR) and Young’s modulus has been examined for different geometric parameters of the structure.Publishe
BENTHIC ALGAE AS BIOINDICATORS IN ASSESSING ECOLOGICAL STATUS OF ČEMERNICA AND DIČINA RIVERS
Full text linkThis study aimed to assess the ecological status/potential of the Čemernica and Dičina rivers (Zapadna Morava basin) based on epilithic diatoms and supporting physico-chemical parameters, as well as to explore indicative properties of the detected macroalgae. The sampling and analysis of benthic algae and measurement of physico-chemical parameters were carried out in August 2023. The ecological status/potential of the Čemernica River was poor to bad at all investigated sites (ČR1, ČR2, ČR3) based on diatom indices and physico-chemical parameters. Low diatom indices values and the presence of the macroalgae Stigeoclonium tenue indicated organic pollution. In the Dičina River, good ecological status was assessed at all sites (DR1-DR4) based on the diatom indices, while poor ecological status has been assessed at almost all sites (DR1, DR2, DR3) based on the physico-chemical parameters, except at DR4, where the ecological status was good. The high coverage of Cladophora glomerata in both rivers indicated nutrient loading, which aligned with the results of the physico-chemical parameters.Publishe
THE FIRE SHE-WOLF BETWEEN CREATION AND DESTRUCTION: THE TRANSFORMATION OF THE SHE-WOLF FIGURE IN WOLF’S SALT BY VASKO POPA
No full textBy singing Wolf’s salt, Vasko Popa built a totemistic, wolf pantheon, whose founders
were the Lame Wolf and the Fire She-Wolf. Their divine, progenitor role was materialized through
periodic meetings, on the border between this and the other side of the sky, which ensured the
renewability of the entire living world. The poetic cycle Fiery she-wolf, which is given the most
attention in the work, thematizes the mythological vision of the she-wolf as the Great Mother, from which everything originates and within which everything returns. Fragments of several
symbolic representations have been summarized in Poppa’s she-wolf, and therefore she is seen as
the supreme deity of a specific animal pantheon who assumes the function of matriarch and at
the same time manifests herself as the embodiment of nature itself. The aim of the work is to mark
the physical and symbolic transformations experienced by the Fire She-Wolf through five songs
of the cycle of the same name: from the creation of the world to the eschaton.http://www.philologiamediana.com/index.php/phm/article/view/974/820Publishe
‘WITH A MILLION PRODUCTS OUT THERE, HOW DO YOU ADVERTISE? YOU DON’T. YOU ODDVERTISE.’: КОРПУСНА АНАЛИЗА НЕКИХ ЕНГЛЕСКИХ ЛЕКСИЧКИХ СЛИВЕНИЦА ЧИЈИ СУ КРАЈЊИ ФРАГМЕНТИ -VERTISE, -VERTISING И -VERTISEMENT
No full textThe paper deals with certain formal and semantic aspects of 197 English lexical blends
the right-hand elements of which are the splinters -vertise (← advertise), -vertising (← advertising),
and -vertisement (← vertisement). It aims to give a detailed analysis of the formal as well
as semantic behavior of the three splinters. The formal analysis of the data shows that all three
splinters prefer to be combined with full left-hand elements, thus forming relatively transparent
structures. The semantics of the analyzed blends indicates that the primary meanings of the
source words advertise, advertising and advertisement, respectively, have remained unchanged,
i.e. that the splinters -vertise, -vertising, and -vertisement simply represent abbreviated forms of
their respective source words. Finally, the results of the analysis of the -vertise, -vertising, and
-vertisement blends suggest quite strongly that, in the people’s constant battle for attention and
profit, almost everything can be a billboard nowadays, from parts of the human body (e.g. legvertising),
animals (e.g. sheepvertising) to roofs (e.g. roofvertisement), sky (e.g. skyvertisement) and
even egg shells (e.g. egg-vertising).Publishe
THE DUNGEON AS THE FALL AND THE APOCALYPSE IN THE NARRATIVE PROSE OF IVO ANDRIC
No full textThe paper examines the semantics of the dungeon in Ivo Andric’s short stories, primarily in the writer’s dungeon stories. In the theoretical footsteps of Northrop Frye, Nikolai Berdyaev and Michel Foucault, we point to the dungeon as two symbolic forms of human fall, external and internal. The outer dungeon is reflected in the social determinants of the ideologically conceived identities of Andric’s heroes, while the inner dungeon is explained through the psychological and ontological aspects of their existence, through the metaphysical rethinking of the idea of freedom – as an impossible free will in the context of modernity which revalues the Biblical concept of innocence. In accordance with such representations, the dungeon is also contextualized through two apocalyptic visions of the human fall that correspond to Berdjaev’s dialectic of external (worldly) and internal (spiritual) apocalypse. It is concluded that the Biblical-Christian semantics of the Fall is deconstructed in Andric’s stories, in order that his heroes become bearers of an absurd desire for ontological salvation, fall as a feeling of modern(istic) self-exile.Publishe
Chemical Composition of Healthy and Raspberry Leaf Blotch Emaravirus-Infected Red Raspberry ‘Willamette’ Fruits
Full text linkThe aim of this study was to determine the changes in chemical composition of fresh red
raspberry ‘Willamette’ fruits caused by the presence of raspberry leaf blotch emaravirus (RLBV). In
three experimental orchards of ‘Willamette’ raspberry, fruits were harvested from RLBV-free and
RLBV-infected plants in 2019 and 2020. Fruits were collected at appropriate maturity stages and
further analyzed in terms of total phenolics, total anthocyanins, and selected individual phenolics. In
all three experimental orchards, the phenolic profiles of the infected and uninfected fruit samples
were considerably different during both studied years. Nonetheless, the intensity of the modifications
varied greatly depending on the location and harvest year. Statistical analysis revealed that the
influence of RLBV infection on the studied features was undeniable, although the influences of
weather conditions and soil composition outweighed the influence of RLBV. Taking into consideration
all the experimental and statistical data, it can be concluded that RLBV had an impact on the
phenolic profile of raspberry ‘Willamette’ fruits, while sensitivity to environmental conditions and
soil composition is emphasized.Publishe