rss_2.0Chemistry FeedSciendo RSS Feed for Chemistryhttps://www.sciendo.com/subject/CHhttps://www.sciendo.comChemistry Feedhttps://www.sciendo.com/subjectImages/Chemistery.jpg700700Epigenetics is Promising Direction in Modern Sciencehttps://sciendo.com/article/10.2478/cdem-2021-0010<abstract> <title style='display:none'>Abstract</title> <p>Epigenetics studies the inherited changes in a phenotype or in expression of genes caused by other mechanisms, without changing the nucleotide sequence of DNA. The most distinguished epigenetic tools are: modifications of histones, enzymatic DNA methylation, and gene silencing mediated by small RNAs (miRNA, siRNA). The resulting m5C residues in DNA substantially affect the cooperation of proteins with DNA. It is organized by hormones and aging-related alterations, one of the mechanisms controlling sex and cellular differentiation. DNA methylation regulates all genetic functions: repair, recombination, DNA replication, as well as transcription. Distortions in DNA methylation and other epigenetic signals lead to diabetes, premature aging, mental dysfunctions, and cancer.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00Low-Cost Sensors for Air Quality Monitoring - the Current State of the Technology and a Use Overviewhttps://sciendo.com/article/10.2478/cdem-2021-0003<abstract> <title style='display:none'>Abstract</title> <p>In recent years the monitoring of air quality using cheap sensors has become an interesting alternative to conventional analytical techniques. Apart from vast price differences conventional techniques need to be performed by the trained personnel of commercial or research laboratories. Sensors capable of measuring dust, ozone, nitrogen and sulphur oxides, or other air pollutants are relatively simple electronic devices, which are comparable in size to a mobile phone. They provide the general public with the possibility to monitor air quality which can contribute to various projects that differ in regional scale, commercial funding or community-base. In connection with the low price of sensors arises the question of the quality of measured data. This issue is addressed by a number of studies focused on comparing the sensor data with the data of reference measurements. Sensory measurement is influenced by the monitored analyte, type and design of the particular sensor, as well as by the measurement conditions. Currently sensor networks serve as an additional source of information to the network of air quality monitoring stations, where the density of the network provides concentration trends in the area that may exceed specific measured values of pollutant concentrations and low uncertainty of reference measurements. The constant development of all types of sensors is leading to improvements and the difference in data quality between sensors and conventional monitoring techniques may be reduced.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00Chemical Electricityhttps://sciendo.com/article/10.2478/cdem-2021-0001<abstract> <title style='display:none'>Abstract</title> <p>In 1800 Alessandro Volta published the results of several years’ work on the phenomenon of electric shocks which he experienced from physical contact with the terminals of his newly developed battery. His work was prompted by Luigi Galvani's explanation of involuntary muscle spasms in frog's legs, which he induced and attributed to animal electricity. Volta's paper opened the floodgates for research in the new field of electrochemistry which has resulted in today's worldwide electric battery industry. This essay explains the sequence of natural events and their explanations which led to the publication of Volta's paper, and gives an overview of the scientific research resulting from Volta's work. This research includes attempts to improve batteries, and the development of ideas which led to a better understanding of matter and the way it interacts with energy. Practical details for the teaching of several important chemical concepts are listed in the appendix. The experiments are related to a reaction which has been known for many centuries - that between iron and copper sulphate solution.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00A Comparative Analysis of Text Difficulty in Slovak and Canadian Science Textbookshttps://sciendo.com/article/10.2478/cdem-2021-0007<abstract> <title style='display:none'>Abstract</title> <p>One of the main purposes of textbooks is the mediation of educational content to students. The factual accuracy of information, as well as the clarity of the text for students plays a crucial role in this aspect. The inadequate text difficulty can complicate students' learning. Comparing different approaches to the text in textbooks, considering the objectives of education, represents key knowledge for teaching materials innovation. This research was therefore focused on the comparison of the Slovak and Canadian science textbooks for lower secondary education. The methodology for assessing text difficulty according to Nestler, Prucha and Pluskal was used for this purpose. The samples of text from the textbooks for 6th and 8th grade of lower-secondary school were assessed. It was found that the text in Slovak textbooks is significantly more difficult. While from the syntactic difficulty point of view differences were rather partial, the significant differences were found in the semantic difficulty of the text. The Slovak textbooks are burdened with an excessive number of professional terms. Considering the results in measuring scientific literacy, this approach to the text in the Slovak textbooks is not effective. The results obtained are therefore an incentive to revise used educational materials.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00The Assessment of Heavy Metal Contamination of the Cultivated Soils in the Odra River Floodplainhttps://sciendo.com/article/10.2478/cdem-2021-0004<abstract> <title style='display:none'>Abstract</title> <p>The aim of the study was to assess the contamination of selected heavy metals in cultivated soils of the Odra river floodplain. The heavy metals Mn, Fe, Cu, Zn, Ni, Cd and Pb were determined in soil samples collected in the autumn of 2020 - after the vegetation period of plants from designated measurement points. Concentrations of the analytes were measured using an atomic absorption spectrometer (F-ASA). A comparison was made between concentrations of heavy metals in soil samples collected from areas flooded in 1997 and from areas flooded as a result of rainfall, snowmelt and winter floods. The results of the studies were compared with the data for soils taken from non-flooded areas. The studies confirmed enrichment of soils subjected to precipitation, snowmelt and winter floods in heavy metals. Also samples taken from two measurement points located on floodplains of the Odra river were characterised by high concentrations of Zn, Cd and Pb.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00Heavy Metals Accumulation in Silver Fir Needles in Swietokrzyski National Parkhttps://sciendo.com/article/10.2478/cdem-2021-0005<abstract> <title style='display:none'>Abstract</title> <p>The article demonstrates the results of the research studies related to the air polluted with heavy metals in the area of Swietokrzyski National Park. The two-year-old needles of <italic>Abies alba</italic> (<italic>Mill</italic>) were used as the bioindicator with the intention of carrying out the research. The studies were conducted in the autumn of 2012. The results showed the spatial variability of concentrations in the range of the analysed metal deposition patterns in the needles of <italic>Abies alba</italic> (<italic>Mill</italic>). The average content of the analysed elements seemed to be the highest in the case of zinc (26.6 mg·kg<sup>−1</sup> d.m.), strontium (6.5 mg·kg<sup>−1</sup> d.m.) and nickel (1.6 mg·kg<sup>−1</sup> d.m.). The research studies revealed that the significant role in determining the content of heavy metals in the two-year-old needles was played by the communication. The highest values were recorded at the research sites situated in the immediate neighbourhood of the voivodeship roads. It was also confirmed that the content of metals was influenced by the so-called low emission from the household and welfare sector together with the remote imission.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00Using the Raspberry Pi Microcomputers in STEM Education in Technically Oriented High Schoolshttps://sciendo.com/article/10.2478/cdem-2021-0006<abstract> <title style='display:none'>Abstract</title> <p>The article deals with learning using the project-based method in STEM education. The article describes the use of ICT technologies, specifically Raspberry Pi microcomputers in bending experiment. The bending experiment was designed for students of technically oriented high schools. Pedagogical research was conducted to determine whether the knowledge and skills of students who have been educated by the project-based method in STEM education are more complex, more systematic and more permanent than the knowledge and skills of students taught by standard forms of teaching. The article presents the results of pedagogical research, which lasted for three years. The results confirm that project-based learning and using ICT in STEM education developed complex knowledge and skills in STEM education. Comprehensive knowledge and problem-solving skills are important for the sustainable development of technological education.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00Civilisation and Its Environmental Consequenceshttps://sciendo.com/article/10.2478/cdem-2021-0002<abstract> <title style='display:none'>Abstract</title> <p>This work is devoted to examining civilisation's environmental consequences and the military confrontation between civilised and barbaric societies. The authors examine antique and ancient Chinese ideas about the phenomenon of barbarism, and also highlight common cultural features inherent in the Germans and Celts and opposed to Rome, and the Far Eastern nomads who were adjacent to imperial China. Moreover, the authors seek to analyse the substantial effects of civilisation on the environment and ecosystem. Having analysed the military potential of civilised societies, the authors come to the conclusion that the victory of barbarism is possible only in the case of civilisation internal collapse. The article outlines other important aspects, including the relationships between civilisation and war and between civilisation and the environment. It concludes with a discussion about rethinking and restructuring some of our perspectives on civilisation.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00Environmental Benefits of Catch Crops Cultivationhttps://sciendo.com/article/10.2478/cdem-2021-0009<abstract> <title style='display:none'>Abstract</title> <p>The role of catch crops in modern agriculture has increased in recent years. In addition to a production of animal feed, they have a positive impact on quality of soil. This study determined the suitability of selected stubble catch crops (white mustard, lacy phacelia, and a mixture of faba bean + spring vetch) to improve production, economic and energy effects of spring wheat grown in 3-year monoculture relative to the control treatment (without catch crops). Two tillage systems were used: conventional tillage and no-tillage (conservation tillage). A field study was conducted over the period 2014-2016 at the Czeslawice Experimental Farm, Lubelskie Voivodeship, Poland. The study proved the high suitability of catch crops to increase the spring wheat yields (under both tillage systems). Regardless of the catch crops, the productivity of wheat was higher under conventional tillage. The catch crops (in particular white mustard) and the conservation tillage system contributed to an improved energy efficiency index of production. The white mustard catch crop also had the most beneficial effect on the economic profitability of spring wheat production. This was due to the low cost of cultivation of this catch crop and its beneficial impact on obtaining high yields of spring wheat.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00Evaluation of Czech Non-Chemical Vocational School Chemistry Textbooks’ Text Difficultyhttps://sciendo.com/article/10.2478/cdem-2021-0008<abstract> <title style='display:none'>Abstract</title> <p>The paper follows the first author's continuous work on chemistry textbook analysis. In the previous paper published in CERP, attention was given to the procedure and results for analysing text-difficulty in lower-secondary chemistry textbooks in Czechia. In this paper, attention was given to non-chemical vocational school chemistry textbooks. They are intended for the most numerous group of upper-secondary students. The goal of the study was to assess the to what extent could students read the textbook texts on their own with appropriate understanding. Therefore, only the textual component was evaluated. The same method (Nestler-Prucha-Pluskal) as in the previous paper was used to analyse the textbooks’ text-difficulty (readability). The results show there are two books which are suitable for students’ own learning. However, there are four textbooks which contain text of high difficulty, including too many scientific terms that they are suitable as teacher's guide through terms rather than student's textbooks. The analysis may serve teachers with their textbook choice as well as researchers who operate in the same field who can easily adopt the methodology and compare results.</p> </abstract>ARTICLE2022-01-21T00:00:00.000+00:00The Kinetics of the Oxidation of Lysine by μ-Peroxo-Bridged Binuclear Cobalt (III) Complex of Succinimide in Aqueous Hydrochloric Acid Mediumhttps://sciendo.com/article/10.2478/ast-2017-0006<abstract><title style='display:none'>Abstract</title><p> Kinetics of oxidation of Lysine (Lys) and mechanisms by μ-peroxo bis[bis(ethylenediamine)succinimidato-dicobalt(III)]dinitratedihydrate; [LCo(μ-O<sub>2</sub>)CoL](NO<sub>3</sub>)<sub>2</sub>.2H<sub>2</sub>O (L = suc(en)<sub>2</sub>), hereafter the complex, was investigated at 420 nm wavelength of maximum absorption of the complex under the conditions hydrogen ions concentration = 1.8 × 10<sup>-2</sup> mol dm<sup>-3</sup>, temperature = 24 ± 1 °C, [LCo(μ-O<sub>2</sub>)CoL<sup>2+</sup>] = 1.4 × 10<sup>-4</sup> mol dm<sup>-3</sup> and ionic strength = 0.5 mol dm<sup>-3</sup>. First order in [LCo(μ- O<sub>2</sub>)CoL<sup>2+</sup>] and [Lys] were obtained but inverse first order in [H<sup>+</sup>]. The proposed overall rate equation is as shown: </p><p>Rate of the reaction decreases when hydrogen ions concentration increase and exhibited converse effect with increase in concentration of ionic strength from 0.1 - 1.3 mol dm<sup>-3</sup>. Added cations and anions affected the reaction rate and the Michaelis-Menten plot passed through the origin indicating no absence of intermediate complex in the electron transfer processes. Putting all the results obtained together, the most probable reaction mechanism is in favour of outer-sphere and an appropriate rate law is established using steady state approximation.</p></abstract>ARTICLE2018-02-16T00:00:00.000+00:00Metalotolerance Capacity of Autochthonous Bacteria Isolated From Industrial Waste Effluenthttps://sciendo.com/article/10.2478/ast-2017-0003<abstract><title style='display:none'>Abstract</title><p> Microbes play significant roles in remediation of heavy metal polluted industrial effluent using the mechanisms of biosorption and bioaccumulation. In the present study, six heavy metal resistant autochthonous bacteria species namely Bacillus cereus, B. megaterium, B. subtilis, Flavobacterium aquatile, Pseudomonas flourescens and Pseudomonas putida were isolated from effluent samples collected from Paper-mill industry (PMI), Paints and Chemicals Industry (PCI), and Steel-rolling Industry (SRI). The isolates were studied for their heavy metal tolerant capacities at different aqueous salt concentrations. Elemental analysis of the industrial effluent samples collected indicated the presence of heavy metals such as Copper (Cu<sup>2+</sup>), Manganese (Mn<sup>2+</sup>), Iron (Fe<sup>2+</sup>) and Lead (Pb<sup>2+</sup>) at varying concentrations in μg/ml. Generally, there were variations in the minimum inhibitory concentrations (MIC) of the heavy metal salt to each of the bacteria understudy. The MIC value of each of the bacterial isolates to aqueous solution of Cu<sub>2</sub>SO<sub>4</sub> showed that B. megaterium, B. subtilis, Pseudomonas flourescens and Pseudomonas putida had the same MIC value of 20 ± 1.5 μg/mL while Bacillus cereus and Flavobacterium aquatile had MIC values of 13 ± 1.3 μg/mL and 25 ± 2.1 μg/mL respectively. This variation was also noticeable in aqueous salts of Mn<sub>2</sub>SO<sub>4</sub>, Fe<sub>2</sub>SO<sub>4</sub> and Pb<sub>2</sub>SO<sub>4</sub>. The bacteria isolates showed sensitivity to heavy metals with increasing zone of inhibition as concentration increased with each isolate showing varying degree of metalotolerance. The effectiveness of the autochthonous bacteria as a means to bio-augment the remediation of heavy metal polluted industrial effluent was further proven and recommended.</p></abstract>ARTICLE2018-02-16T00:00:00.000+00:00Analysis of the importance of art elements in the construction of ecological environment in the new erahttps://sciendo.com/article/10.2478/eces-2021-0039<abstract> <title style='display:none'>Abstract</title> <p>With the development of economy, people have higher and higher requirements for living art. A good ecological environment is the guarantee of creating an aesthetic environment. Taking the ecological environment construction of ecological town as an example, this paper analyses the importance of integrating artistic elements into the ecological environment construction in the new era from the perspective of environmental aesthetics. Based on the concept of "three life integration" and "garden city theory", this paper creatively puts forward the construction methods and models of ecological environment in contemporary small towns. Based on the height of environmental aesthetics, this paper analyses the planning and construction process of characteristic town and the evaluation and acceptance criteria of ecological environment design, summarises its successful experience and main problems, and makes a retrospective summary and reflection. This paper analyses the importance of the integration of art elements into the ecological town in the new era. The results show that in the new era of ecological environment construction, the integration of art elements can not only improve the quality of ecological environment construction, but also improve the common people's cognition of ecological beauty.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00The cognition of the spatial art forms of tourist villages based on ecological engineering and sustainable developmenthttps://sciendo.com/article/10.2478/eces-2021-0038<abstract> <title style='display:none'>Abstract</title> <p>With the development of information technology, the improvement of production processes and lifestyles, and the transformation of commercial economic models, the traditional agricultural industry cannot meet the increasing material and cultural needs of villagers. Therefore, the development of traditional tourist villages has transformed into being based on ecological engineering and sustainable development. The starting point of the existence of such tourist villages will be the protection and development of traditional villages. At the same time, the village space is the material carrier for the development of rural tourism, and the construction of a spatial form that is compatible with the tourism resource utilization model can effectively promote the development of rural tourism. Based on SWOT analysis, this article carefully analyses and summarises the domestic research on the sustainable development of tourist villages. The results show that such sustainable development effectively avoids the excessive development of resource elements during rural construction, which can lead to waste, and promotes the optimal use of resources. Since rural tourism has taken a sustainable development path, the average annual compound growth rate has reached as high as 31.2 %, which is considered very rapid growth. Tourist operating income has reached more than 30 %. It is expected that the national rural tourism income in 2021 will exceed 10,000 trillion yuan. Tourism villages will continue to consider ecological engineering and sustainable development as the starting point for promoting the development of rural tourism in China, popularising consumption, standardising services, diversifying benefits, and making products unique.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00Sustainable development of antarctic krill environmental resources based on system dynamicshttps://sciendo.com/article/10.2478/eces-2021-0031<abstract> <title style='display:none'>Abstract</title> <p>Antarctic krill mainly inhabit the Antarctic Ocean, not far from Antarctica, especially the Weddell Sea, where krill is dense. Marine fisheries have reached new levels, but the topic of sustainable use of marine fishery resources is far from reaching the required levels. In order to study the sustainable development of the Antarctic krill environment, this paper studies the living environment and applicability of Antarctic krill based on system dynamics, and provides some references for the sustainable development of marine resources. Mentioned the use of case analysis method, literature analysis method and other methods to collect data, build a Model, and read and analyse a large number of related literatures through the literature survey method. The experimental results proved that the salinity has a significant effect on the survival rate of Antarctic krill (<italic>p</italic> &lt; 0.05). When the salinity is 34, the molting frequency reaches its maximum value, which is 70 %. It is concluded that the ability of Antarctic krill to adapt to gradual changes in salinity is stronger than that of sudden changes in salinity, and the suitable salinity for survival is 30-42. With 34 as the basic salinity, when the salinity rises within a certain range, the molting rate of krill will increase, and as the salinity decreases, the molting rate will gradually decrease. This shows that improving the environmental resources of Antarctic krill is an effective method for improving salinity.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00Analysis of the main body behaviour of non-point source pollution control based on multimodal game modelhttps://sciendo.com/article/10.2478/eces-2021-0037<abstract> <title style='display:none'>Abstract</title> <p>The issue of agricultural non-point source pollution has attracted the attention of the state and the masse. In the non-point source pollution control organizations which composed of the governments, farmers and fertiliser sellers, due to the characteristics of rational economic body, the phenomenon of ”market failure” and ”government failure” may occur in the process of non-point source pollution control. In this paper, the author applies game theory to analyse the main behaviour characteristics of the three main bodies, and constructs the incomplete information dynamic game model that the government, farmers and fertiliser sellers participate in. According to the results of the equilibrium solution of the Haysani Axiom model, it is found that the decisions made by the three bodies of the government, the fertiliser seller and the farmer in the behaviour choice stage have a great influence on the behaviour choice of the other two bodies, and the process of each strategy choice by the three bodies is a dynamic game process of the three bodies. Finally, according to the main influencing factors reflected in the equilibrium solution, proposed the related non-point source pollution control countermeasure suggestion to the government main body.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00Experimental study on the working and mechanical properties of high performance cementitious structural groutshttps://sciendo.com/article/10.2478/eces-2021-0032<abstract> <title style='display:none'>Abstract</title> <p>By using the experimental study method, the working properties and mechanical properties of grouting materials were determined by changing the cement-sand ratio, water-cement ratio, and cement admixtures. The main factors affecting the properties of grouting materials and the mutual influence rules of various factors are analysed and determined, and the best value range is obtained. Finally, the compressive strength of 28-day ordinary Portland cement structure grouting is optimised to 50-80 MPa. Based on the grouting ratio of ordinary Portland cement, an experimental study on the early strength structure paste of sulphate aluminate cement was carried out. The paste with one day strength as high as 70 MPa and good compatibility was prepared, and the early strength change law of the optimum ratio was deduced.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00Research on low carbon financial support strategies from the perspective of eco-environmental protectionhttps://sciendo.com/article/10.2478/eces-2021-0035<abstract> <title style='display:none'>Abstract</title> <p>This paper provides an in-depth analysis and research on low carbon financial support strategies from the perspective of ecological environmental protection. The understanding and analysis of the development status of ecological environmental protection inspectors, the analysis of the current rule of law construction, organizational structure, operation mechanism and capacity of the current ecological environmental protection inspectors, the understanding of the defects and problems in the work of the inspectors, to provide a basis for improving the inspection function. Through financial instruments It is of great theoretical value and practical significance to realise the full utilization of resources, the optimization of industrial structure and the low-carbon cycle development of agricultural economy. Combining the current situation and constraints of financial support for low-carbon agriculture, we propose targeted financial policy recommendations such as credit innovation for agricultural green projects rich in characteristics and conducive to the development of low-carbon agriculture, broadening private financing channels for low-carbon agriculture, and exploring low-carbon agricultural insurance. The entropy value method is used to determine the index weights, and the comprehensive evaluation method is used to calculate the comprehensive development evaluation value of the two subsystems; finally, the coupling coordination degree model is used to analyse the coupling degree and coupling coordination degree of the carbon finance and low-carbon agriculture composite systems, and the factors affecting the coupling coordination degree are analysed on this basis. Although the coupling level between them is at a low level of coupling, it is in transition to a medium coupling; the coupling coordination degree is at a mild disorder, and gradually in transition to a near disorder.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00The government-business relationship and eco-innovation: evidence from chinese automobile industryhttps://sciendo.com/article/10.2478/eces-2021-0036<abstract> <title style='display:none'>Abstract</title> <p>This study used 2017-2019 Chinese A-share-listed automobile manufacturing companies as research samples to analyse the impact of the government-business relationship on eco-innovation. We found that a healthy government-business relationship had a positive impact on enterprise eco-innovation. The mediating effects test verified that a healthy government-business relationship affected enterprise eco-innovation through financing constraints. In addition, managerial ownership significantly increased the positive impact of a healthy government-business relationship on enterprise eco-innovation. We also found that a healthy government-business relationship had a more substantial impact on enterprise eco-innovation in non-state-owned enterprises when considering corporate property rights. The study results provide empirical evidence for the influence of the government-business relationship on enterprise eco-innovation and deepen our understanding of eco-innovation in China’s automobile manufacturing industry.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00Model of environmental management science based on circular economy theoryhttps://sciendo.com/article/10.2478/eces-2021-0034<abstract> <title style='display:none'>Abstract</title> <p>The resources of a country are limited, and people must consider the important issue of how to make use of these limited material resources to create major economic value for humans. The theory of the circular economy has been proposed, which relies on scientific model research to create economic development that is more in line with people’s concept of environmental management. The circular economy is characterised by resource conservation, recycling, coordination, low development, high utilization and low emissions. All material and energy use is reasonable, and sustainable land use minimises the influence of economic activities on the natural environment. Based on the theory of the circular economy, this paper studies the model of environmental management science. This paper analyses the mining development mode, the mechanism of the circular economy, and green logistics research based on circular economy theory and then applies statistical analyses to the two models. It summarises the development mode and the mechanism of the mining circular economy based on the current mineral resource development and utilization situation and the environmental problems in China. An innovative mode mechanism for mining circular economy development is proposed that can provide a value evaluation standard for social development. Through the above research, it is found that the use of circular economy theory can not only help make effective use of resources but also provide a new way to improve the gross national product.</p> </abstract>ARTICLE2022-01-18T00:00:00.000+00:00en-us-1