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Pollack Periodica
Authors: Orest Voznyak, Nadiia Spodyniuk, Olena Savchenko, Iryna Sukholova, Mariana Kasynets, and Oleksandr Dovbush

Abstract

The work is devoted to study of thermal efficiency of heating convectors with aluminum ribbing to ensure comfortable indoor conditions. The purpose of this paper is to evaluate theoretically and experimentally the thermal efficiency of convector-type heaters with aluminum ribbing, to implement numerical simulation and to obtain dependencies for determination of thermal characteristics of convector-type heaters with aluminum ribbing, ensuring of a proper both indoor climate in the premise and energy saving. A nomogram of interdependence between heat amount, heat carrying medium flow rate, the initial and final temperatures was created. Heat quantity increases with increasing heat carrying medium flow rate, the inlet temperature and decreases with increasing of the exit temperature.

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Abstract

With the gradual improvement of urban construction, more and more experts and the public realized that the speed of urban development be reasonable, which caused urban regeneration to turn to a new-minded “urban micro-regeneration”. “Micro-regeneration” is an extension of the concept to the direction of urban construction. The concept of micro-regeneration was first applied to the regeneration of individual buildings in the old city. The research on the intervention of public art in urban micro-regeneration is still in its infancy in China. Based on practice, this paper explores the possibility of public art's intervention in urban micro-regeneration.

Open access
Progress in Agricultural Engineering Sciences
Authors: N. Anter, M. Y. Guida, M. Kasbaji, A. Chennani, A. Medaghri-Alaoui, E. M. Rakib, and A. Hannioui

Abstract

In this scientific paper, thermochemical conversion of redwood (RW) was studied. Using the thermogravimetric analysis' technique (TGA), the thermal behavior of RW samples was examined at four heating rates ranging from 5 to 20 K min−1 in inert atmosphere between 300 and 900 K. Two main objectives have been set for this study; the first one was the determination of the kinetic decomposition parameters of RW (Pinus sylvestris L.), and the second one was the study of the variation of characteristic parameters from the TG-DTG curves of the main RW's components, such as; cellulose, hemicellulose and lignin. The kinetic analysis was performed using three isoconversional methods (Vyazovkin (VYA), Friedman (FR) and Flynn-Wall-Ozawa (FWO)), Avrami theory method and the Integral master-plots (Z(x)/Z(0.5)) method to estimate activation energy (E a), reaction order (n), pre-exponential factor (A) and model kinetic (f(x)) for the thermal decomposition of cellulose, hemicellulose and lignin components.

The DTG and TG curves showed that three stages identify the thermal decomposition of RW, the first stage corresponds to the decomposition of hemicellulose and the second stage corresponds to the cellulose, while the third stage corresponds to the lignin's decomposition. For the range of conversion degree (x) investigated (0.1 ≤ x ≤ 0.7), the mean values of apparent activation energies for RW biomass were 127.60–130.65 KJ mol−1, 173.74–176.48 KJ mol−1 and 197.21–200.36 KJ mol−1 for hemicellulose, cellulose and lignin, respectively. Through varied temperatures from 550 to 600 K for hemicellulose, from 600 to 650 K for cellulose and from 750 to 800 K for lignin, the corresponding mean values of reaction order (n) were 0.200 for hemicellulose, 0.209 for cellulose and 0.047 for lignin. The pre-exponential factor's average values for three components of RW ranges from 0.08 × 1012 s−1 to 2.5 × 1012 s−1 (A hemicellulose = 1.09 × 1012 s−1), 0.10 × 1014 s−1 to 0.28 × 1014 s−1 (A cellulose = 0.17 × 1014 s−1) and 3.07 × 1016 s−1 to 3.69 × 1016 s−1 (A lignin = 3.33 × 1016 s−1), respectively. The experimental data of RW had overlapped the D 4, D 2 and F 3 in the conversion degree of 10–30%, 30–55% and 55–70% for the three components, respectively.

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We are pleased to announce that the latest Journal Impact Factor (JIF) and SCImago Journal Rank (SJR) scores are available for all our indexed journals. The former informs us about the mean number of citations an article from a given journal published between 2019 and 2020 received in 2021 (see Clarivate), while the latter is indicative of the mean number of weighted citations earned in 2021 by an article published between 2018 and 2020 in a given journal (see SCImago).

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Magyar Pszichológiai Szemle
Authors: Anita Deák, Regina Balázs, Tímea Fodor, Ádám Csery, Zsófia Hanna Bulla, Veronika Erdélyi, Júlia Kopácsi, Anetta Lázár, Fanni Szecsei, and Tamás Bereczkei

Studies conducted in the framework of Jaak Panksepp's Affective Neuroscience Theory provide a new approach to understand the emotional basis of personality. The Affective Neuroscience Personality Scales (ANPS) developed by Panksepp and Davis is a common and widely used self-report tool to measure primary emotional traits. The ANPS consist of three positive scales (SEEK, CARE, PLAY), three negative scales (ANGER, SADNESS, FEAR), and Spirituality. Although the ANPS is available in 15 languages, the Hungarian version has not been developed, yet. The aim of the current study is to fill in this gap and report the result of the Hungarian version. Healthy adults (N = 910) participated in a cross-sectional study and filled in the Behavioral Inhibition and Activation Scales (BIS/BAS), and the Positive and Negative Affective Scales (PANAS). Reliability values of all ANPS scales are good (Cronbach-α = 0.74–0,90). The confirmatory factor analysis supported both the two-factor model and the six-factor model of the emotional traits. The findings of the convergent and discriminative validity are as expected. The Hungarian version of the ANPS has good psychometric properties, and it is suitable for measuring the six primary emotional traits. The ANPS is an appropriate self-report tool for studies in the field of affective neuroscience, clinical psychology, and cross-cultural research.

Open access
Pollack Periodica
Authors: Réka Wittmanová, Jaroslav Hrudka, Ivana Marko, Andrea Raczková, and Štefan Stanko

Abstract

Dynamical modeling in water supply and treatment and wastewater treatment helps to understand the flow in the networks. Therefore, it is important to incorporate dynamic modeling into the design and assessment processes and operation for the future of urban drainage systems.

The aim of this paper was using a mathematical model to analyze the functionality of combined sewer networks during a precipitation event on 13 October 2020. The analysis was performed based on the results from the assessment of the hydraulic capacity of the sewer network using the MOUSE model in the MIKE URBAN software. This study results that the evaluated sewer network does not fulfill his purpose during heavy rainfall events.

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Pollack Periodica
Authors: Osman Metalla, Marsida Klemo, Azem Hysa, Elvis Çela, Abdullah Diku, and Migena Nako

Abstract

This paper represents a noise pollution survey in Durrës city, Albania. There are four survey areas defined: A (central), B (industrial), C (suburban), D (residential + beach) during two intervals times (morning and night).

The equipment used for noise measurement was Testo 816-1 where data were categorized according to levels L eq, L min, L max, and L ave. The contrast of L eq levels versus the standard levels based on the 2002/49/EC Directive showed that L eq levels overcome the limits.

In conclusion, the high equivalent noise level mostly has been during the morning with L eq > 55 dB, which brings serious health concerns to residents near these regions. At night in most of these stations, the equivalent noise levels resulted higher than 45 dB, which is above EU directive and Albanian standards. The survey results will also serve local institutions to manage the situation and to address problems at the governmental level.

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Let E, G be Fréchet spaces and F be a complete locally convex space. It is observed that the existence of a continuous linear not almost bounded operator T on E into F factoring through G causes the existence of a common nuclear Köthe subspace of the triple (E, G, F). If, in addition, F has the property (y), then (E, G, F) has a common nuclear Köthe quotient.

Open access

Abstract

This study was designed to investigate the effects of green tea on lipid profile, liver tissue damage, and oxidative stress in rats fed a diet including high fructose. Sprague-Dawley rats were randomly divided into four groups: Control (C), Fructose (F), Green Tea (GT), and F+GT. F and F+GT groups were given 20% fructose in the drinking water for eight weeks. Green tea (2 mg kg−1) was administrated to GT and F+GT groups by oral gavage for eight weeks. Biochemical parameters in serum and oxidative stress markers in the liver were analysed. The liver sections were stained with haematoxylin-eosin. As of the 3rd week of the experiment, the body weight of rats in the F group showed a statistically significant increase in comparison with the F+GT group. The serum glucose and triglyceride levels of the F+GT group significantly decreased when compared with the F group. The fructose-induced degenerative changes in the liver were reduced with green tea. Green tea may serve a protective role against hyperlipidaemia and liver injury in rats fed a high fructose diet.

Open access

Abstract

Indigenous yeast strains Kluyveromyces marxianus (MH6), K. marxianus (CH1), and Saccharomyces cerevisiae (C1) were screened for whey beverage production. K. marxianus (MH6) showed significantly higher (P < 0.05) fermentation efficiency (15.2%) as compare to other yeast strains. The conditions optimised for whey fermentation were 16 Brix, pH 5.5, 28 °C, and 72 h without agitation. For fermented whey beverage production, fruits viz., kinnow (Daizy), guava (Allahabad safeda), and mango (Safeda) were blended with whey at different ratios viz., 80:20, 70:30, 60:40, and 50:50. All ratios showed significant differences for biochemical and sensory analysis (P < 0.05), out of which ratios 60:40, 70:30, and 60:40 for whey kinnow, whey mango, and whey guava, respectively, were selected. To enhance the flavour of whey beverage, flavouring agents (cinnamon, cardamom, fennel seeds, and apple essence) were added. A panel of judges assessed all whey beverages on a hedonic scale basis, and cardamom whey guava beverage received the highest score of 8.16. The whey beverages were stored under refrigerated conditions after pasteurisation, and the shelf life was assessed to be 15 days. This study conferred that K. marxianus held the potential for fermented whey fruit blend beverages production and these beverages could be an alternative healthy refreshing substitute for synthetic bottled fruit beverages.

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