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The work analyses an impact of a drainage system, established in 1939 on overgrown pine tree stand in longer period of time. For the purposes of study 14 sample plots, established by scientists K. Buss and P. Zalitis during the 50's and the beginning of 60's, were remeasured. Sample plots were organized in the Myrtillosa turf. mel., Vacciniosa turf. mel., and Callunosa turf. mel. forest site types. Stands basal area increased in all compared forest site types, maximal being 41.7 m2 ha-1 in Myrtillosa turf. mel. fo...

The issue of biochar application as a non-conventional fertilizer is of growing interest currently. Biochar is a product of the pyrolysis of organic waste for example and unlike conventional fertilizer, biochar is a long-acting agent. The use of such fertilizer should not only increase the yield of crops, but also the sequestration of carbon in the soil and reduce the impact on climate change. An additional advantage of biochar is its developed surface, which makes it possible to use it as a carrier for beneficial...

This article presents the potential of biochar used in wastewater treatment processes and sludge management in small installations - for the maximum maintained number of users equal to 50. The possibilities of two substances used in sewage management processes, such as char and biochar will be presented. These substances, produced from pyrolysis, are stable carbon-rich compounds which have various beneficial applications like soil conditioning, remediation and wastewater treatment. In particular, biochar originati...

A new joint configuration system has been developed to achieve a higher strength and ductility. The joint system consist of a reinforced concrete wall and a composite steel-concrete beam. The study aims for an experimental and a numerical part in a FEM program Abaqus 6.13. The program consist to reproduce the behavior of the joints and the materials variation. The purpose of the paper is to investigate the main parameters that affect the response on the contribution of the steel-concrete materials that influences ...

Worldwide, bananas are commonly consumed. Due to this fact large amounts of banana peels waste are generated. Banana peels contain adequate amounts if starch. The aim of this study was to evaluate the quality of vinegar obtained from banana peels in comparison with other types of commercial vinegar. Color, total dry extract, total titratable acidity, specific gravity, total soluble solids, antioxidant capacity and polyphenols content were determined on different types of vinegar. The analyzed samples were three ty...

Medical materials based on natural polysaccharides can be used as hemostatic sorbents and dressings. In this work, some samples of sponges had been obtained based on sodium alginate and chitosan. The concentration of sodium alginate in the solution, the ratio of alginate and chitosan were varied during an experiment. Polysaccharide cross-linking was carried out by inotropic gelation or by combining ionotropic gelation with ionic substitution. According to the literature, a chitosan have antibacterial properties ag...

Prices of urban real estate are formed under the influence of several groups of factors, among which we can identify demand and supply, characteristics of the external market environment, specifics of users, factors of effective use, etc. However, the role of factors is not equal, and the redistribution of their "weight" occurs almost constantly. The importance of the environmental factor (both positive and negative points) is generally not in doubt, but its impact on real estate prices is also constantly changing...

Low-cost sensors, either electrochemical, optical or light scatter based and piezoelectric, due to low price and performance explainability are becoming more available for monitoring, studying and explaining urban air quality. This paper explores low-cost sensor technology applicability for air quality measurements in urban territory. At least two month long monitoring campaigns were conducted during summer 2018 in Riga (Latvia). For validation purposes different monitoring sites were selected in order to assess i...

Allocation of electricity exchanges between bidding zones represents one of the major challenges of European Electricity Market. Initially, it was an ATC capacity basedallocation mechanism for electricity markets. Currently, a powerflow based allocation method it is intended to be implemented. Starting from the premise to more efficiently use the transmission networks, the authors addressed the issue of transmission capacity and their related transmission costs allocation from theperspective of zonal approach. Aut...

Sustainability of energy sources and environmental protection play an increasingly important role in civil engineering design. Due to global warming, people are well aware of the importance of protecting nature, as extreme weather events are occurring more frequently. The lack of water becomes a serious problem in still larger and larger areas all over the world. For this reason, drinking and rain water reservoirs as well as wastewater treatment plants have been presently popular and frequently used structures. Fr...

The utilization of different waste materials in concrete as partial replacement of cement or filler is having importance today, mainly on account of the improvements in the long-term durability of cement composites combined with ecological benefits. Fly ash (FA), Granulated Blast Furnace Slag (GBS), Silica Fume (SF) or High Reactive Metakaolin (HRM) is materials, which confirm to these requirements. However, a number of case studies with other waste materials are described in the literature as well. Copper slag is...

Previously it was believed that stress influence on microorganisms is only negative, reducing the efficiency of biosynthesis. However, it has been shown now that with the use of controlled stress, it is possible to increase the efficiency of microbial cultivation processes. Among other types of stress, oxidative stress is the most significant. When microorganisms are exposed to oxidative stress agents, breaks can occur in nucleic acid molecules as well as of protein molecules, in addition to this, the blockage of ...

Environmental pollution represents one of the serious problems of our society. During anthropogenic activities (mining and ore processing, metal processing industry) toxic compounds and heavy metals are introduced into our environment. Their accumulation in ecosystems creates a huge environmental load and it threats environment and human health. Another emerging environmental threat is a genetic pollution. Genetic pollution is an uncontrolled gene (usually antibiotic resistance gene) flow into populations of non-t...

Environmental pollution represents one of the serious problems of our society. During anthropogenic activities (mining and ore processing, metal processing industry) toxic compounds and heavy metals are introduced into our environment. Their accumulation in ecosystems creates a huge environmental load and it threats environment and human health. Another emerging environmental threat is a genetic pollution. Genetic pollution is an uncontrolled gene (usually antibiotic resistance gene) flow into populations of non-t...

The aim of the study was to compare the functional and technological properties of protein concentrates (PC), protein-calcium composites (PCC) and protein concentrates hydrolyzed by endoprotease and exopeptidase (HPC) with a degree of proteolysis of 3.89-4.16%. All kinds of concentrates were obtained from white and brown rice. It was found that the functional properties are higher in BC obtained from white rice than in brown rice rice. Thus, the foaming capacity is 5-6 times higher, but the stability of foam in br...

Scots pine (Pinus sylvestris L.) stands are regenerated by planting, and only small portion (c.a. 13%) by self-seeding in Latvia. Seeds for plant production are collected only in seed orchards ? thus represent the results of tree breeding. Aim of our study was to assess the growth and damages as determined by forest type and genetics in Scots pine stands at the age of first commercial thinning. Tree parameters were measured in Scots pine open-pollinated progeny trials on mineral soils, differing by fertility (poor...

Computer Aided Design (CAD) is the reality of today?s architecture. Building Information Modelling (BIM) technique is a great opportunity for communication and data management in virtual space. Theoretically BIM has a sophisticated database, where the resulting software can simultaneously create the data and generate ?reports? about it, in the form of drawings. BIM cloud-based collaboration provides up-to-date information, where project data is at the centre of the process and delivered to the point of work, makes...

In every technology as well as in Horizontal Directional Drilling (HDD), there are design challenges. Compliance with the requirements forces the application of modern solutions in the mentioned technology. One such solution is the Intersect Drilling method. The Intersect Drilling technology makes it possible to create a hole for Horizontal Directional Drilling of shallow layers and a longer length compared to conventional methods. The decision on whether the Horizontal Directional Drilling (HDD) project should be...

The aim of this study is to estimate the outcome of special cutting method developed for old pine stands in Riga?s forest park Mezaparks. Its topicality is defined by the increase in urban population, cities? areas, and green spaces there. The functions of cities? green areas are specific and it is very important to develop and evaluate special methods of forest management for urban forests. The research was carried out in the forest park Mezaparks, in a 183-year old Scots pine stand with an area of 4.32 ha, where...

In our study, we optimized two methods of enzyme activity estimations characterizing C and P cycles (?-1,4-glucosidase and acid phosphatase) for agricultural soil with 2.629% of total C and 0.062 % of total N sampled in Tatarstan (Russia). Concentration of the substrates (4-MUF-?-d-glucopyranoside, 4-MUF-phosphate) in the range from 20 to 900 ?mol g-1 soil was used, four levels of buffer pH (3, 6, 8, 11) were compared, and three different dilutions of soil suspension (1%, 2%, 10% w/v) were investigated. Besides, t...

With the beginning of the 21st century, there was a rapid development of technologies allowing to cover elevation of buildings with various plant species, even those that are not adapted to the natural overgrowth of vertical walls. This is the result of changes in the approach to the sustainable design. The technologies that derive from the simplest, proven solutions known for thousands of years become popular. Plants have a number of advantages that are very difficult to replace by modern filtration systems, they...

The issue of biochar application as a non-conventional fertilizer is of growing interest currently. Biochar is a product of the pyrolysis of organic waste for example and unlike conventional fertilizer, biochar is a long-acting agent. The use of such fertilizer should not only increase the yield of crops, but also the sequestration of carbon in the soil and reduce the impact on climate change. An additional advantage of biochar is its developed surface, which makes it possible to use it as a carrier for beneficial...

The study of coagulation behaviour of bentonite clay suspensions is presented in this paper. Experimental results were obtained by investigation of several chemical and physical properties of two bentonite suspensions. The study included several measurements such as particle size distributions, chemical and phase analysis of prepared suspensions, as well as preparation of sedimentation graphs and the relationship between concentration of the suspension and turbidity. The results of this research could help in dete...

The present article reports numerical results of laminar natural convection heat transfer within an air filled semi cylindrical cavity with its horizontal walls submitted to different heating models. In this work, the horizontal surface is maintained at constant temperatures Tc (Dirichlet condition) or heat fluxes q (Newman condition), while that of the opposite surface is considered at cold temperature Tf. The parameters governing the problem are the Rayleigh number (103 < Ra < 106), and the Prandtl number (Pr = ...

Shoot cultures of the essential oil-bearing Artemisia alba Turra were established with the aim of the in vitro exploration of the biosynthetic potential and physiological behavior of the species. Plant growth regulators were applied in order to affect morphogenesis in vitro and to search for possible relations with secondary metabolites production of the plant. As a result of the applied treatments, two morphotypes of the in vitro cultured A. alba individuals were induced, based on the development of roots of the ...

Environmental change is, today, an unavoidable cause of societal stress that leads to suffering and migration. The focus here is not on change itself, but on the local and regional resources and environment conditions that frame both the extent of change and the alternative actions that might mitigate effects. In this context, a modelling approach to resource and risk assessment and possible responses change is presented. Complex systems are not initially suitable for a bottom-up approach to modelling that assumes...

Medical materials based on natural polysaccharides can be used as hemostatic sorbents and dressings. In this work, some samples of sponges had been obtained based on sodium alginate and chitosan. The concentration of sodium alginate in the solution, the ratio of alginate and chitosan were varied during an experiment. Polysaccharide cross-linking was carried out by inotropic gelation or by combining ionotropic gelation with ionic substitution. According to the literature, a chitosan have antibacterial properties ag...

When thinking about sustainable design, social sustainability appears to be a fundamental feature that must be considered when shaping people and communities. This broad subject is narrowly approached within the present article following one specific viewpoint; social sustainability can be defined in the design process by analyzing materials? potential in crafts` and industries` activities alike. Paper`s potential on both these levels, in developing, through its production process, small scale communities and larg...

The paper presents the results of the experiences organized on the tailings dump resulting from the surface mining of lignite in Rovinari, Gorj county, for testing the effects of a fertilizer assortment, such as: liquid fertilizers based on humates extracted from lignite, complex mineral fertilizer (N105 P105 K105 and N150 P150 K150), farmyard manure (20, 40 and 60 t/ha) and compost (20, 40 and 60 t/ha), as well as mixtures of the two types of organic fertilizers with mineral fertilizer. Sunflowers have been used ...

The article presents the methodology of conducting experiments related to the process of composting under laboratory conditions. For this purpose, a set consisting of eight fully metered reactors imitating the composting process under real conditions was built. In the insulated chambers, bayonet thermometers were placed, air coolers, condensate tanks and drains were installed. During composting experiments with daily measurements, the composition of gases coming from individual reactors is examined, i.e. CO2, NH3,...

This paper presents a joint research program conducted by the scientific contribution of Amirkabir University of Technology (Tehran Polytechnic) and the Technical University of Cluj-Napoca Romania aiming at developing sustainable Self-Consolidating Concrete (SCC) mixtures for using in concrete New Jersey barriers. The research program included an assessment on the fresh and hardened properties of: C25/30, C35/45, C40/50, and C50/60 strength classes of concrete mixtures to be used in the prefabrication of concrete ...

In the polluted area with emissions from Zlatna metallurgical plant, more than 50,000 ha of agricultural and forestry land has been affected by pollution over a time period of 200 years. Approximately 5,000 ha from these lands were severe and extremely polluted. The vegetation was completely destroyed on more than 2,000 ha, leading to intense erosion processes. The forest vegetal cover was completely destroyed, and the trees had some dry branches, spots on leaves, bark burns and even completely destroyed, the oak ...

Situation distance control after flood and inundation is one of the main problem to be solved by space monitoring of emergency situations, developed in Kazakhstan since 2001 y. It is connected with annual emergency situation which is developed in every region of water bodies representing potential or real imminence. During last three years there were heavy floods passed in Kazakhstan, especially in Akmola, Pavlodar, Karaganda regions. There is an acute security issue during spring time inundation, till nowadays th...

Correctly planning and designing are first steps and key aspects to achieve sustainable development, economic, social and environmental. Sustainable construction brings required performance on economic, social and cultural improvement. Sustainability in construction industry has more point of view. Building Information Modelling presents tool which meets the information requirement for sustainability design. Building Information Modelling (BIM) is one of the most progressive technology in construction field. BIM t...

Universities attract a large number of students and staff who generate thousands of journeys every day. This affects transport systems in European cities and contributes to increasing CO2 emissions, since a significant percent of the journeys are made by car. Therefore, there is a need to influence the academic community?s travel behavior and to encourage staff and students to reduce car journeys and to increase travel by public transport, bike, or by foot. This would result in reduction of the negative effects fr...

The basic rationale for the research was the lack of landscape planning approaches within the spatial planning process in Croatia. The most important deficiency addressed in this research was an integral inclusion of the public opinion and their values into the planning process. Dealing with the conflicts which may arise from it represents one of the activities that are taken into account within landscape planning. Shortage of an integrated approach to landscape planning in Croatia causes conflicts between differe...

Shoot cultures of the essential oil-bearing Artemisia alba Turra were established with the aim of the in vitro exploration of the biosynthetic potential and physiological behavior of the species. Plant growth regulators were applied in order to affect morphogenesis in vitro and to search for possible relations with secondary metabolites production of the plant. As a result of the applied treatments, two morphotypes of the in vitro cultured A. alba individuals were induced, based on the development of roots of the ...

The paper shows selected results of the analysis of the number of people changes including periodical and long lasting staying of people at the room and the heat zones forming in some types of large-volume buildings. The possibilities of the use of those results in the green building design are considered.It is based on the research performed in the large-volume buildings, especially residential and sacral buildings. Here are some calculations of the changes of the people staying inside the building and its influe...

Considerable efforts have been devoted to the exploration of Latvian forest resources as the most significant national natural wealth. The State Forestry Research Institute is conducting the statistical forest inventory, is fixing the data of felling and recovery of forest stands. Detailed statistical information for the assessment of different aspects is available. In recent years, the consumption of certain woody biomass products, such as chips and pellets, has a tendency to grow, due to a number of factors: the...

Waste management is an important element of environmental protection in each country. Vegetable and fruit waste are produced in every place in the world, hence it is necessity to manage it. Legal regulations in Poland forbid the storage of this waste which were selectively collected. Therefore, it is necessary to looking for other methods of their management. Agricultural biogas plants are an important source of renewable energy. In last years, in Europe, the most important substrate used for biogas production was...

Pyrolysis is considered as an effective and alternative way to treat organic waste and to obtain pyrolysis fuels as well as biochar. The latter may be used for different purposes in industry and agriculture, including use as a long term fertilizer. Biochar, after pyrolysis, is obtained in the form of powder; however from practical point of view it is better to use pelleted or granulated biochar since it significantly enhances biochar?s filed distribution. In our study we compared the efficacy of granulated and pow...

The Intersect Drilling method is a modern drilling technique for HDD (Horizontal Directional Drilling), giving a completely new dimension to Horizontal Directional Drilling technology. Its creation was mainly due to the need for drilling in difficult conditions, where drilling with the use of only one drilling device is often impossible or ineffective and could end in the failure of the entire project. To cope this it is necessary to apply modern solutions in this technology. One such solution is the Intersect Dri...

Geophysical exploration, the necessary part of oil and gas exploration, generates more and more data, subject of processing. The most powerful super computer clusters are used by business and academic institutions. However, often it is necessary to have evaluation of the measured data shortly after measurements, even in the field. Modern computer architectures, namely Graphic Processing Units (GPUs) and Field Programmable Gates Arrays (FPGAs) provide a good basis for PC-based fast data processing, to have, say, su...

The mouth areas of the seas are the most interesting and complex objects for studying the distribution of pollutant flows and the factors of their formation. Different approaches can be used to identify pollutant flows and the role of the geochemical barriers, in particular the analysis of the distribution of marker compounds that most clearly reflect the pollution levels themselves and possible sources of their entry into the components of the aquatic systems. Polycyclic aromatic hydrocarbons (PAHs) are considere...

Hybrid larch is fast growing and more wind-resistant than Norway spruce; thus, it might be a suitable alternative to reduce (diversify) the forest management risks in context of climate changes. However, interest to use this species in forest regeneration, recently higher than before, is still limited. In part it is related to lack of experience and information on its growth. Therefore aim of our study was to characterize growth of Larix x eurolepis young stands in Latvia. Sample plots were placed in 7 stands of t...

The present study was conducted in order to investigate the effect of various organic food acids, on the proteolytic processes taking place in chicken. A poorly acidic medium favors the process of tenderizers the meat, this being a chemical method of accelerating proteolysis. Citric acid from lemon juice, lactic acid derived from yoghurt and borscht, acetic acid of natural fermentation have been used for this purpose. Meat samples were marinated in these media for 3 days, being preserved at the refrigeration tempe...

The paper deals with the possibilities of metal recovery from sediment from sludge disposal site after mining activity from locality Zlate hory. The locality is protected from mineralized water, which represents a potential threat for groundwater. This work deals with the use of bacteria Acidithiobacillus ferrooxidans to bioleach polymetallic ores (Cu, Zn, and Fe) from these locality. It is a simple and effective method to recover metals from mineral raw materials, where conventional methods cannot be applied. As ...

The study presents the comparative analysis between pressure and carbon dioxide charts obtained after measuring a series of fermentation processes. Doughs used for measurements were obtained from different quality/extraction flours, type 650 and whole wheat (1850). Gathered data was used to verify a mathematical model for determination of carbon dioxide production during the fermentation process, using pressure variation in a sealed container (reactor). For the testing it was used an experimental stand composed of...

Conventions, agreements and international regulations aimed at counteracting climate change impose on the signatory Governments, including Poland, the obligation to document the amount of greenhouse gases emitted to the atmosphere. Inventory is taken from various industrial sectors, including sources related to the exploitation of crude oil. In the oil production processes, greenhouse gas emissions come from three main sources categories: combustion emissions (stationary and mobile sources), released (process) emi...

Romania has an important rail network, of public use, consisting of about 10764 km of railway, some of which are affected by instability phenomena. Although the percentage of areas affected by instability in the entire network is insignificant, railway sections have some peculiarities, any difference in the order of the centrimetres appearing at the upper level of the rail can lead to the closing of the line, with important financial consequnce. The surface, affected by the instability phenomen was about 4,000m2, ...