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The article discusses one key characteristic of irreversible processes: in order to bring the system back to its original state following such a process, some energy is inevitably dissipated as heat into the surroundings. Greater dissipation indicates greater irreversibility. In the limit that the amount of energy dissipated approaches zero, the process is said to be reversible. This concept is illustrated by considering isothermal expansion of an ideal gas, free expansion of an ideal gas into vacuum, heat transfer from a hotter object to a colder one, phase change, and chemical reactions.
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TiO2-M (M = Cd, Co, Mn) were synthesized by sol-gel method using titanium(IV) isopropoxide (TTIP) and cadmium sulfate octahydrate (CdSO4.8H2O), manganese(II) sulfate monohydrate (MnSO4.H2O), cobalt(II) sulfate heptahydrate (CoSO4.7H2O) as precursors. M-doped TiO2 was performed with molar ratio 1:3; 1:2; 1:1; 2:1; 3:1 (mol Ti / mol M) and photocatalytic processes using visible light with irradiation time for 5, 10, 15, 20, 25 and 30 minutes. This study was carried out to determine the effect of different metal ions, the composition of Ti:M and the exposure time on the photocatalytic degradation of methylene blue dye. The results showed that different metal ions influenced crystal size and affected electronic properties (band gap). Crystal size of TiO2 > TiO2-Mn > TiO2-Co > TiO2-Cd and band gap of TiO2 > TiO2-Cd > TiO2-Co > TiO2-Mn. In addition, differences of Ti:M composition also influenced the photocatalytic activity. The longer of applied time exposure, the higher photocatalytic degradation of methylene blue was achieved. The optimum composition of Ti:M was obtained at Ti:M ratio by 3:1 with degradation values by 92.56% (TiO2-Cd), 90.44% (TiO2-Co), and 89.42% (TiO2-Mn).
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We present an innovative electromotive force (EMF) measurement technique to study the kinetic behavior during alkaline hydrolysis of ethyl acetate. The explicit feature of this research is the application of green chemistry ideas that are inherent in the experiment. Using the new approach, we find that the kinetic behavior of the reaction under study follows second order with an estimated rate constant value at 25°C to be 2.45 × 10-3 cm–3 min–1. This value is in excellent agreement with the conventional end-point neutralization titration method discussed previously in the literature. The novel EMF measurement technique is simple, fast, accurate and eco-friendly. Keeping in view of long-term sustainability of the ecosystem, we feel that there is an urgent need to switch over from conventional laboratory practices to green chemistry approaches. Further, the method discussed here may prove to be extremely useful for teachers, researchers and students who wish to carry out kinetic study of other systems.
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The objective of this study was to verify an impact of different Cd ion concentrations on metabolic (biochemical) parameters in blood of egg chickens. Taking in to consideration that change of these values reflects the level of damage of the vital organs like liver, kidneys, hart etc. These vital organs determine the health status, growth and development of organisms. In the total of four groups of chickens have been included in the experiment. Three groups were treated with different concentrations of cadmium (2, 4 and 6 mg/kg) while one group was set as a control group without treatment. Eleven different biochemical parameters have been measured and analyzed such as: total proteins, albumins, globulins, aspartate transaminase, alanine transaminase, lactate dehydrogenase, gamma-glutamyl transferase, alkaline phosphatase, blood urea nitrogen, creatinine and glucose. The results indicate the significant changes on the level of biochemical parameters in blood, by increasing the cadmium concentration. The level of albumins, alanine transaminase, lactate dehydrogenase, gamma-glytamyl transferase, and creatinine has been decreased significantly compared to control group while other parameters were increased. The biochemical parameters between treatments were changed significantly. Total levels of proteins, globulins, aspartate transaminase, alanine transaminase, gamma-glutamyl transferase, creatinine and glucose has been increase by increased the cadmium concentration. While in another hand, biochemical parameters such as lactate dehydrogenase and alkaline phosphatase has been decreased significantly when the Cadmium was increased. Changes on biochemical parameters are an indication showing that, cadmium effects are negatively oriented on metabolic processes of feed on egg-layer chickens.
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The antioxidant capacities, total phenolic and flavonoid content of five different extracts (Et2O, CHCl3, EtOAc, n-BuOH and H2O) of Primula veris (L.) growing wild in Kosovo were analyzed. Total phenolic and flavonoid content were quantitatively determined to the Primula veris (L.) growing wild in North-Western part of Kosovo in two different altitude levels (670 m and 1200 m). The amount of total phenolics in Primula veris (L.) extracts ranged from 5.10 mg GAE/g d.e. in altitude 1200 m to 17.30 mg GAE/g d.e. in altitude 670 m. The amount of total flavonoids in Primula veris (L.) extracts ranged from 12.15 mg RE/g d.e. in altitude 670 m to 31.43 mg GAE/g d.e. in altitude 1200 m. Free radical scavenging capacity (RSC) was evaluated by measuring the scavenging capacity of extracts on DPPH, NO as well as on hydrogen peroxide (H2O2). EtOAc, n-BuOH and H2O extracts of Primula veris (L.) expressed very strong scavenger activity. On the other hand, Et2O and CHCl3 extracts showed much weaker effect in the neutralization of DPPH, NO and H2O2. The observed differences in antioxidant activity could be partially explained by the levels of phenolics and flavonoids in extracts of Primula veris (L.). Hence, this plant can be used to discover bioactive natural products that may serve as leads in the development of new pharmaceuticals.
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As a result of the complex structure of the higher boranes, thebalancing of redox reactions with their participation by the oxidation number methodis connected with the acceptance of non-integer values of the oxidation numbers ofthe boron atoms which is in contradiction with some IUPAC recommendations. Analternative method is the material balance method (algebraic method) based on thenatural law of mass conservation in chemical reactions. Its modified form permitseasy and fast balancing of redox reactions without any restrictions.
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Total phenols, flavonoids, flavonols and anthocyanis content and antioxidant activity were quantitatively determined to the Tussilago fatfara (L.) growing wild in Sharr (South part of Kosova). In the tested extracts of plant species Tussilago fatfara (L.) quantitative composition of total phenols, flavonoids, flavonols and anthocyanins were determined by spectrophotometric method. Total phenols determined by Folin-Ciocalteu reagent and their amounts in the range of 56.50 mg/g to 84.70 mg/g (expressed as gallic acid equivalent, mg GAE/g). The amounts of flavonoids in plant extracts are in the range of 2.75 mg/g to 8.76 mg/g (expressed as rutin equivalent, mg RE/g).The amount of total flavonols in Tussilago farfara (L.) extracts ranged from 0.21 mg RE/g to 0.51 mg RE/g. The contents of total anthocyanosides in the Tussilago farfara (L) ranged from 1.44 (ethanol extract) to 1.86 (acetone extract) anthocyanins determined as mg yanidin 3-glucoside/g dry weight. Antioxidative activity was determined in vitro, using the DPPH reagent by spectrophotometric method.The results demonstrated that extract RSC was dependent on the solvent polarity, and the type of free radical used in the reaction. The IC50 values extracts in DPPH• assay was from 0.10 mg/ml (ethanol extract) to 0.20 mg/ml (acetone extract).
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Music and movement are essential components of human existence since the dawn of time. In childhood it is important to join the two experiential dimensions since this juxtaposition responds to basic needs, natural characteristics of the developmental stage of human personality. This research used the methodology of the psychological and pedagogical experiment and illustrated that cognition and the musical game are closely correlated in terms of learning English. The result was improvement of the linguistic performance in terms of higher level vocabulary acquisition and pronunciation obtained by a test group when compared to the control group.
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The text explains how non-formal education is becoming increasingly important and complements and builds the formal, how to assess non-formal learning in the activities we manage as pedagogues. A wealth of knowledge is accumulated in integrated lessons, excerpted in nature training and childrens' research projects. Thus, in time, a database is created for the environmental status of the area around the school; environmental problems are outlined; identified are the needs for specific actions to clean and protect nature.
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The text explains how the idea for this children academy arises, what are the objectives, tasks and activities of the project. In the text you can find information about the time schedule and the students that cover the project as well as about its sustainability.
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The text contains information about activities in studying the audiences of cultural products in Bulgaria; identifying the types of audiences and the most popular cultural events by region; distinguishing the most popular ritual practices in modern times and restoring them in their authentic form; studying the ritual dishes that were consumed during rituals in past and recording their recipes. The project team created a workshop “Cultural and Educational Cooperative”. The initiative ended with a practical conference and a ritual show.
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The paper considers some geometric connections among different notable points in the quadrilateral. What are obtained are three notable circles and two notable lines which contain some of these points.
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The Zagreb connection indices are molecular descriptors (topological indices) which have recently been introduced by Ali & Trinajstić (2018). A novel/old modification of the first Zagreb index, Mol. Inform., to appear]. This paper is devoted to establishing general expressions for calculating the Zagreb connection indices of a well-known nanostructure, namely the Titania nanotube TiO2.
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A series of novel substituted thiazolidyn-4-ones were synthesized by cyclization of various Schiff bases of chromen-3-one with thioacetic acid. 3-(1-4-Amino-phenylamino)-ethyl-4-hydroxybenzopyran-2-one 3 is synthesized in high yield by condensation reaction of 4-hydroxy-3-acetylcoumarin 2 and 1,4-benzenediamine. The catalytic condensation of product 3 with benzaldehyde and their analogues (salicylaldehyde and 3-nitrobenzaldehyde) yielded corresponding 3-[1-(4-benzylidene-amino)-phenylamino]-ethyl-4-hydroxybenzopyran-2-ones 4(a-c). The cyclization reaction of compounds 4(a-c) with thioacetic acid yielded corresponding substituted thiazolidin-4-ones 5(a-c). The structures of the synthesised compounds were established by FT-IR and NMR spectrometric data and their elemental analysis. Compounds of series 4(a-c) and 5(a-c) were screened for their antibacterial activity against S. aureus, E. coli and Klebsiella by Diffusion Disc Method. Antibacterial activity of the compounds 4(a-c) and 5(a-c) against S. aureus, E. coli and Klebsiella was examined by measuring the zones of inhibition around the disks impregnated with the corresponding solutions in N,N-DMF concentration 2 mg/mL , 4 mg/mL and 6 mg/mL. Compounds of series 4 exhibited significant antibacterial activity, whereas compounds of series 5 displayed moderate activity against these microorganisms. The impact of substitutions in antimicrobial activity was also explored.
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The implementation of the programme for the development of inclusive education in the Republic of Moldova will contribute to ensuring equal opportunities and access to quality education for every child at all levels of the educational system. The article describes the presentation of Educational Inclusion exhibition – a priority of the National Education, which was displayed at the International Conference „Problems of inclusive education in the Republic of Moldova: perspectives and practical solutions", which was at the Alecu Russo State University of Balti (19-20 October)
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The paper analyses the way how foreign elementary and high school students are registered and defined in census data, and in official Hungarian educational statistics. Based on these operationalisations the author tries to describe the current situation and the size of foreign student population in Hungary. In order to have an insight of the relationship between the school success and the rate of foreign students of the school, in the final part of the study the author uses the database of National Assessment of Basic Competencies. The author also uses some results of the first and second generation migrant students of the PISA 2015.
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The study was carried out in 2016–17. It aimed at revealing teachers’ views on multiculturalism and multicultural education together with their concept about migrants and immigrant children. When constructing a framework of interpretation, we supposed that views on multicultural education and attitudes concerning migrants would be connected to, or, indeed, interrelated with teachers’ national identity, as well as their previous experiences of diversity. The results of the questionnaire research based on a sample of 368 pre-service and in-service teachers demonstrate that multicultural views and attitudes are strongly correlated with those on migration. The sense of threat seems to be interrelated with an essentialist national identity, which on the other hand has a negative relationship with the ethnic diversity of the respondents’ families and their social environment.
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In this text concerning the schooling of the children of immigrants in France, we describe three institutional solutions. We will first talk about optional courses devoted to learning the languages and cultures of the countries of origin. Secondly we discuss the problems related to educational priority aeras. Thirdly, there will be school groups created to help the children of immigrants learn French. It will also discuss the services developed to support the activity of professionals, such as a specialized journal, the website of the Observatory of Priority Aeras, and activities of the school administration units involved in the education of children of the immigrants who also function as a resource center. We also highlight the difficulties described in the analyzes concerning the institutional solutions presented.
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