2020

Selle valdkonna püsiv URIhttp://hdl.handle.net/10492/5955

Sirvi

Nüüd näidatakse 1 - 20 234

Estimate of manure present in compost dairy barn systems for sizing of manure storage
(2020) Damasceno, F.A.; Monge, J.L.; Nascimento, J.A.C.; Andrade, R.R.; Barbari, M.; Saraz, J.A.O.; Ferraz, G.A.S.
Milk production is increasingly modernized as a result of the growing demand for food around the world. Improvements in livestock facilities are observed, with a large increase in the use of feedlot systems such as the Compost Dairy Barn. Increasing milk production in confinement systems has also raised concerns such as the management of wastes (water, faeces and urine) from the system, which has become one of the most important issues in the intensive dairy farms. The aim of this work was to estimate the amount of manure present in compost dairy barn systems in order to size the manure storage. The study was conducted at four compost dairy barns in southern Minas Gerais, Brazil. These compost barns had different bedding materials and dimensions. In each farm, data on milk yield and quality (daily production, fat and protein content), animal weight and amount of feed ingested by the animals were collected. Total-day manure delivered by the cows in the feeding alley and milking parlour was piled up together and weighed. Based on the results, it was observed that, in the compost dairy barns, only part of the total manure produced per day was delivered in the milking parlour (1.6 and 2.0%) and in the feed alley (27.6 to 49.3%). These results are very important for designers for the proper manure management system design of the dairy farms.
What happens to peat during bog fires? Thermal transformation processes of peat organic matter
(2020) Ozols, V.; Silamikele, I.; Kalnina, L.; Porshnov, D.; Arbidans, L.; Krumins, J.; Klavins, M.
Bog fires are a serious natural phenomena. Major increase in the number of fires has happened during the last decades due to bog transformation into agricultural lands, accidents and human activities. During bog fires the peat is exposed to high temperatures due to which chemical transformation and even mineralisation of peat can occur. The aim of the study was to analyse the impacts of the bog fires on the bog as an ecosystem, advance the understanding and knowledge of fire impact on peat and humic matter properties and application possibilities. As the material for the study peat samples from burnt sites and thermally treated peat were used. To reveal peat transformation during bog fires, thermogravimetric analysis of peat samples were done, where amounts of bitumens, humic acids and mineral matter were estimated. During bog fires thermal modification of peat properties takes place, resulting in full mineralisation of peat and release of mineral substances. Bog fires lead to development of peat char, bitumens and significant changes in structure and properties of peat humic acids. However, from perspective of application of peat as a substrate and from perspective of impacts on the bog ecosystems, the effects are negligible.
Comparing RGB - based vegetation indices from UAV imageries to estimate hops canopy area
(2020) Starý, K.; Jelínek, Z.; Kumhálová, J.; Chyba, J.; Balážová, K.
Remote estimation of hops plants in hop gardens is imperative in field of precision agriculture, because of precise imaging of hop garden structure. Monitoring of hop plant volume and area can help to predict the condition and yield of hops. In this study, two unmanned aerial vehicles (UAV) – eBee X senseFly UAV equipped with Red Green Blue (RGB) S.O.D.A. camera and Vertical Take-Off Landing (VTOL) UAV FireFly6 Pro by BirdsEyeView Aerobotics equipped with MicaSense RedEdge MX camera were used to acquire images of hop garden at phenology stage maturity of cones (24 th July) before harvest. Seven commonly used RGB vegetation indices (VI) were derived from these RGB and multispectral (MS) images after photogrammetric pre-processing and orthophoto mosaic extraction using Pix4Dmapper software. Vegetation Indices as the Green Percentage Index (G%), Excess of Green Index (ExGreen), Green Leaf Index (GLI), Visible Atmospherically Resistant Index (VARI), Red Green Blue Vegetation Index (RGBVI), Normalised Green Red Difference Index (NGRDI) and Triangular Greenness Index (TGI) were derived from both data sets. Binary model from each of VI was derived and threshold value for green vegetation was set. The results showed significant differences in hop plant area based on the specifications of cameras, especially wavelengths centres, and design and flight parameters of both UAV types. The comparison of various indices showed, that ExG and TGI indices has the highest congruity of estimated vegetation indices in hop garden canopy area for both used cameras. Further processing by Fuzzy Overlay tool proved high accuracy in green canopy area estimation for ExG and TGI vegetation indices.
The biological basis for the use of protein growth stimulant made from cattle split for wheat foliar feeding and disease suppression
(2020) Kolesnikov, L.E.; Kremenevskaya, M.I.; Razumova, I.E.; Kolesnikova, Yu.R.; Tambulatova, E.V.; Yazeva, E.O.
The new modern preparation – protein growth stimulant – was generated in accordance with technology of employees of Saint-Petersburg ITMO University and SaintPetersburg State Agrarian University. Biological activity of the preparation was determined by measurements of 20 indicators of the wheat productivity. In addition, 16 indicators of different types of pathogenesis were determined. These can be formed at distribution of Helminthosporium root rot, wheat rust species, powdery mildew and wheat leaf blotch. The use of the protein growth stimulant promoted increase of potential yield in 80% of samples. In comparison with the control, 15 wheat varieties, treated with the preparation, showed an increase in the main productivity indicators: the length of the spike, the number of spikelets per spike, the weight of 1,000 grains, the productive tilling capacity and the general bushiness. The intensity of Helminthosporium root rot development decreased 11.9% (it was found in 53.3% of samples) and the wheat leaf blotch by 15.6% (in 66.7% of samples). The wheat brown rust development intensity decreased insignificantly (3.6% compared to the control). In the same time, values of the pathogen pustule area decreased at average by 79.8%. There was an increase in total nitrogen in wheat leaves at 92% of samples. As was revealed, the effectiveness of the protein growth stimulant largely depends on the wheat variety. To conclude, the prospect of using the new effective protein growth stimulant to increase productivity of wheat and protection from diseases was shown.
Combustion and emission studies of a common-rail direct injection diesel engine with various injector nozzles
(2020) Hissa, M.; Niemi, S.; Niemi, A.
Fuel injection has a critical role in an internal combustion engine and a significant effect on the quality of the fuel spray. In turn, fuel spray directly affects an engine´s combustion, efficiency, power and emissions. This study evaluated three different injector nozzles in a highspeed, non-road diesel engine. It was run on diesel fuel oil (DFO) and testing was conducted at three different engine loads (100%, 75% and 50%) and at two engine speeds (2,200 rpm and 1,500 rpm). The nozzles had 6, 8 and 10 holes and a relatively high mass flow rate (HF). The study investigated and compared injection and combustion characteristics, together with gaseous emissions. The combustion parameters seemed to be very similar with all studied injector nozzles. The emission measurements indicated general reductions in hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) at most load/speed points when using the 6- and 10-hole nozzles instead of the reference 8-hole nozzles. However, smoke number increased when the alternative nozzles were used.
Utilization of fused deposition method 3D printing for evaluation of discrete element method simulations
(2020) Hnízdil, P.; Chotěborský, R.; Kuře, J.
FDM 3D printing is used for designing prototype assessment in engineering production. It is usually used to verify the functionality of kinematics mechanisms. It can also be used for innovation in agricultural production, eg. the development of new mechanisms for agriculture tools. Such a mechanism as well as the entire components is printed using FDM and they are made of plastics. This whole can be experimentally verified in a laboratory trough. The article deals with the verification of the possibilities of using FDM technology for the design of agricultural tools. The material properties, namely stress-strain, of the plastics after printing are entered into the Ansys mechanical library, and the DEM results are also imported into Ansys mechanical. Material properties of plastics for FDM technology such as PLA, PETG show that its mechanical properties limited their using for validation.
Experimental research into the effect of harrowing unit’s operating speed on uniformity of cultivation depth during tillage in fallow field
(2020) Bulgakov, V.; Nadykto, V.; Kaminskiy, V.; Ruzhylo, Z.; Volskyi, V.; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
Retention of soil moisture is an urgent topic of the day in the cultivation of agricultural crops. Using fallow fields is one of the ways to solve the named problem, but the tilling of such fields requires observing some special conditions, in particular, the capillary effects in their upper soil layers must be cut down. For that purpose, the authors have proposed a special harrow equipped with the tools capable of fulfilling the above-mentioned task. The authors have carried out extensive field experiment research into the tillage of fallow soils with the use of the said implement. In order to apply the implement, a new harrow unit has been developed. The results obtained during the experiment research have been processed with the use of statistical methods and it has been established that the depth of harrowing in the tilled field decreases, when the operating speed of the combined unit under consideration increases to 3.3 m s –1 . At the same time, the variances of oscillations of the parameter under research in accordance with the Cochran's C test remain uniform. Also, the frequency of the harrowing depth oscillations changes insignificantly. That is supported by the correlation lengths of the normalized correlation functions of the process under consideration, which, at the above-mentioned operating speed, stay within the sufficiently narrow range of values: 0.16–0.20 m. According to the results of the experimental investigations, the maximum value of the normalized cross-correlation function for the relation between the oscillations of the field harrowing depth and the oscillations of the field’s longitudinal profile does not exceed 0.12. This testifies to the absence of any substantial interrelation between the said two stochastic processes, which is quite reasonable in view of the small values of the variance and period of the oscillations of the field’s longitudinal profile. The probability of the new combined tractor and harrow unit maintaining the tolerance of the fallow field cultivation depth oscillations within the range of ± 1 cm is equal to 82%. Within each 1.85 m of the distance travelled by the combined soil cultivation unit under consideration, only one instance of the field cultivation depth deviating from the ± 1 cm tolerance can be expected.
Seed size and cold stratification affect Acer negundo and Acer ginnala seeds germination
(2020) Kiseleva, O.A.; Loretts, O.G.; Veselkin, D.V.
The aim of this work is to determine how the germination of seeds of the invasive tree Acer negundo depends on the period of cold stratification under the snow and the duration of stratification in the air on the branches of the trees. For comparison with A. negundo, we used seeds of Acer ginnala, introduced but not invasive tree in the Middle Urals. The period of stratification in the air modeled by collecting seeds in October and December. The duration of cold stratification under the snow was 0, 1, 2, 3 and 4 months. We hypothesized that the duration of stratification in the air did not affect the germination of A. negundo and A. ginnala seeds. Cold stratification under the snow had a positive effect on seed germination of both species. The best seed germination of A. negundo and A. ginnala was after 4 months of cold stratification under the snow, the germination rate differs: in A. negundo 12 ± 4% (small seeds) and 79 ± 7% (large seeds), in A. ginnala – 1 ± 2% (small seeds) and 18 ± 4% (large seeds). In both species, large seeds germinated at 7 to 18 times more intensively than small ones. In A. ginnala case, even after cold stratification under snow for 4 months, no more than 22% of the seeds germinated. The germination of A. ginnala seeds was 4–5 times lower than that of A. negundo seeds.
Ozone treatment of stored potato tubers
(2020) Hutla, P.; Kolaříková, M.; Hájek, D.; Doležal, P.; Hausvater, E.; Petráčková, B.
During storage, potato tubers are susceptible to different pathogen, which can attack the skin and flesh of the tubers. The most serious damage can be caused by rot inducing bacteria and fungi. A possible way to prevent microbial damage may be the use of ozone in the air ventilated through the stored tubers. However, the tubers can undergo qualitative changes, e.g. dehydration and loss of starch content. This article presents the results of a five-month experiment in which ozone concentration of 5 mg m-3 was periodically introduced in some of the stored potato tubers of the cultivar ‘Dali’. All potato tubers were stored in closed storage boxes with a metal frame and wood panels in the floor and walls (ground area 1.6×1.2 m, height 0.95 m) which were continuously aerated using the ambient air in a potato warehouse. There was 900 kg of tubers stored in the box. At the end of the experiment, the ozonated variant was compared with the control (not treated). The ozone-treated tubers had 2.95 times lower incidence of infection by rot and the number of microorganisms on healthy tubers was lower than the control. The ozone-treated tubers were less frequently dehydrated. The water loss was higher in control by 0.86 %. There was no significant difference in silver scurf manifestation or in the starch content between the two variants.
Modelling the effect of sowing date on the emergence, silking and yield of maize (Zea mays L.) in a moderately warm and dry production area
(2020) Széles, A.; Huzsvai, L.
This research focused on accurately modelling emergence (VEEmergence) and silking (R1) dates using 5 cm deep soil temperature (ST) and how sowing date (SD) affects VEEmergence and R1 date of different maturity hybrids and which is the optimum sowing date in the changed climate. Three sowing dates were used between 4th April and 10th May. The same maize hybrids (FAO 290, FAO 350, FAO 420) were involved in the experiment between 2011–2013. The 5 cm deep soil temperature could be used for simulating the date of VEEmergence and R1 and the Percentage of Predicted Deviation (PD) was below 10%. When calculating the effective heat units (HU) at 5 cm depth, setting 6 °C as base temperature leads to better modelling. SD did not clearly affect yield since due to the influence of genotype and crop years. The FAO 290 hybrid had the lowest yield (11.534 t ha-1) and it responded sensitively to sowing date. Its highest yield (12.788 t ha-1; P < 0.05) could be obtained with SD3. FAO 350 and FAO 420 hybrids provided stable yields without any significant effect of SD. The highest yield was provided by the FAO 420 hybrid (13.494 t ha-1) with a wide SD interval (4th April – 10th May). The obtained findings help farmers in making grounded decisions to obtain high and stable yield under the changed climatic circumstances. The obtained findings help farmers in making grounded decisions to obtain high and stable yield under the changed climatic circumstances.
The use of DNA markers for the evaluation of maize lines and hybrids based on cytoplasmic male sterility
(2020) Prysiazhniuk, L.; Honcharov, Y.; Chernii, S.; Hryniv, S.; Melnyk, S.
The use of cytoplasmic male sterility (CMS) is very important for the production of maize hybrids. The new inbred lines and hybrids of maize of Ukrainian breeding were studied. In the field, four pairs of sterile analogue of line RL106S were obtained during four backcrossing (17М, 19М, 23М, 27М and 29М) and maintainer lines of RL106fS (18М, 20М, 24М, 28М and 30М) for S type cytoplasm and RL108C (195С, 201С, 205С, 207С, 209С) і RL108fC (196С, 202С, 206С, 208С, 210С) for C type respectively. For S type, the following combinations were obtained: RL23S×RL106fS, RL107S×RL106fS, RL98S×RL106fS, RL105S×RL106fS, RL113S×RL106fS and for C type: RL109C×RL108fC, RL110C×RL108fC, RL112C×RL108fC, RL114C×RL108fC, RL115C×RL108fC. The obtained hybrid combinations were planted the following year in a control nursery for field trials. According to the results of the field assessment, all the hybrids were sterile. The types of sterility of the studied lines and hybrids were determined using polymerase chain reaction (PCR) with specific primers for C and S types of cytoplasms. The presence of specific amplicons 398 and 799 bp was determined in sterile lines with C and S types of cytoplasm, respectively. Amplicons 398 and 799 bp were identified in simple-cross and simple reconstituted hybrids on a sterile basis, and can be used to determine the type of hybrid and its maternal component at the stages of selection and examination of new hybrids.
Changes in soil properties and possibilities of reducing environmental risks due to the application of biological activators in conditions of very heavy soils
(2020) Šařec, P.; Látal, O.; Novák, P.; Holátko, J.; Novák, V.; Dokulilová, T.; Brtnický, M.
This study aims at verifying the effect of farmyard manure (FYM) and of selected activators (Z'fix and NeoSol) on changes of soil properties. Their application should lead to improvement of soil physical properties and of organic matter fixation, to reduction of environmental risks, e.g. of tillage energy requirements. Experimental variants (0.7 ha each) were as follows: I (FYM with Z'fix); II (FYM with Z'fix + NeoSol); III (FYM); IV (Control NPK only). FYM was applied at rates: 50 t ha-1 (2014); 30 t ha-1 (2016). Additional NPK fertilizer (I–IV) was applied according to annual crop nutrient normative. The agent Z'fix was used as an activator of FYM biological transformation (5.5 kg t -1 ). The agent NeoSol was used as soil activator (200 kg ha-1 ; annually). In order to verify the effect, cone index, bulk density, tillage implement draft and chemical soil components (Humus, C/N ration and Ntot) were measured annually. Compared to the control, the application of FYM combined with the mentioned agents (I–III) increased Ntot more than two times. Moreover, it decreased (I–III) bulk density by 8.7%. Tillage implement draft decreased by 3% after the application of FYM with Z’fix (I, II). The study confirmed that FYM application combined with utilization of activators positively influenced soil fertility and helped to reduce environmental risks.
The effect of yeast growth stages on the absorption of polyphenols
(2020) Harbah, R.A.; Meledina, T.V.; Morozov, A.A.
Colloidal stability of beer is one of the most critical challenges facing the brewing industry. In brewing, stabilization agents are widely used to remove colloids such as proteins and polyphenols. However, the removal efficiency of polyphenols depends on the yeast, which adsorbs these compounds on its surface. The adsorption of polyphenols on the yeast surface is associated with the zeta potential of the cell wall, which correlates with the mannan content in them. The purpose of the study was to investigate the role of yeast strains in adsorption of polyphenols (increasing colloidal stability of beer) and the correlation of this property with the mannan content in the cell wall during the fermentation. Two S. cerevisiae strains were used in this study, and the specific growth rate of yeast, the specific rate of change in the polyphenol content and the mannan content were determined. The results of this study showed that the highest mannan content in yeast was after 9 hours (the end of exponential growth phase). Its content was 10.97% by weight of dry matter in the yeast S. cerevisiae Californian Lager (M54), and 13.69% in the yeast S. cerevisiae Belgian Wit (M21). The desorption of polyphenols was observed during the period from 9 to 24 hours of fermentation, where an increase in the content of polyphenols in the medium was observed. Based on these results, it is necessary to remove the yeast at the end of the exponential growth phase to increase the colloidal stability of the beer.
Variation in the mass and moisture content of solid organic waste originating from a pig complex during its fermentation
(2020) Shalavina, E.; Briukhanov, A.; Vasilev, E.; Uvarov, R.; Valge, A.
The focus of the study was the fermentation of an organic waste mixture originating from a pig-rearing complex. The organic waste was processed in the laboratory-scale drum fermenter. Through the fermentation process, the fermented material was weighed by a system of four strain gauges installed under the fermenter. In our previous study, the following initial mixture characteristics were justified to have the fermentation process going – 65% to 70% moisture content and 400–600 kg m-3 density. The optimal operation mode of the fermenter was identified depending on the initial mixture composition – aeration frequency of 5 min h-1 ; air consumption of 11.3 m3 h -1 per 1.7 m3 of the fermenter volume; drum rotation interval – three times every 12 hours. Under this operating mode, the mass loss was 3% already on the third fermentation day and 7% – on the fifth day. As a result, the mass of the finished organic fertiliser was 9% smaller than that of the loaded mixture. The moisture content of the processed material also decreased: under the average moisture content of the loaded mixture of 68.7%, the average moisture content of the organic fertiliser was 66.4%. Based on the resulting experimental data, the mathematical models describing the dependence of the mass and moisture content of the processed material on the fermentation time were created. The study outcomes allow concluding that the solid-state aerobic fermentation is one of the promising options for the utilisation of the solid fraction of pig slurry.
Monitoring the species diversity of medicinal plants typical for the south slope of Hissar Ridge / Tajikistan /
(2020) Sattarov, D.S.; Vyshegurov, S.Kh.; Galeev, R.R.
This paper is a summary of literature reviews concerning the diversity of medicinal plants and the results of our many years studies. It includes scientific and practical justifications of the importance of monitoring species diversity of the studied object. Results of monitoring the species composition of wild medicinal plants in some areas of the southern slope of the Gissar Range are specified. As a result of studying 11 gorges (Gazhne, Safedchashma, Gusgarf, Shamal, Obi-Zugora, Gulobod, Yos, Yavroz, Semiganch, Odzhuk, Magov), 174 species of medicinal plants were found that belong to different botanical taxa. This number of plants includes representatives of 106 genera belonging to 46 families, among which representatives of the aster family predominate: Asteraceae (36 species), Rosaceae (19 species), Lamiaceae (16 species), etc. Compared with the number of known plants growing within the territory of the Republic of Tajikistan, the number of species found was 11.6%. In relation to the number of plants that are recognized as medicinal in the world, species diversity of the southern slopes of Gissar Range is less than one percent. However, the number of species is comparable to locations with similar climatic conditions.
Advantages of electric resistance method for baking bread and flour confectionery products of functional purpose
(2020) Kulishov, B.; Kulishova, K.; Rudometova, N.; Fedorov, A.; Novoselov, A.
In this paper we studied the effect of the baking method on the preservation of betacarotene in two types of products: pan wheat bread and sponge cake. Five sources of betacarotene were used in the study, three of which are commercially available samples, and the two others are experimental samples of supramolecular complexes of beta-carotene with alpha- and beta-cyclodextrins in powder form (molecular ratio 1: 1). Bread and sponge cake were baked by convective and electric resistance methods. The values of temperature and current flowing through the dough were monitored during electric resistance baking. The beta-carotene content was measured in the dough after kneading, in the cake batter after mixing and in the finished products after baking and cooling. The beta-carotene content was evaluated by spectrophotometry after extraction. The control samples of bread and sponge cake were baked without adding beta-carotene. Different sources of beta-carotene exhibited varying stability in bread and sponge cake. Bread samples baked by the electric resistance method with addition of supramolecular complexes had minimum losses of beta-carotene. Electric resistance baking ensured lower losses of beta-carotene in bread and sponge cake samples.
Composting olive pomace: evolution of organic matter and compost quality
(2020) Ameziane, H.; Nounah, A.; Khamar, M.; Zouahri, A.
Morocco is one of the major olive-producing countries with an annual production of 1.56 million tonnes, part of which is dedicated to olive oil production. This important production generates, in addition to oil as the main product, a significant amount of waste (pomace and olive mill wastewater). The latter, when released in large quantities into the natural environment, cause fatal pollution. A suitable valuation of this waste will allow a clean and sustainable production for the sector. This work consists of composting olive pomace from the traditional system with two structural agents (poultry droppings and cattle manure) and comparing the two composts in terms of composting process parameters (pH, electrical conductivity, organic matter temperature, etc.), organic matter dynamics and compost quality, with manual aeration of the compost. Despite the high humidity level of the used pomace (80%), the adopted composting conditions have been effective in reducing high levels of organic matter and therefore organic carbon, as well as reducing the extreme phytotoxicity of the pomace. The experiment showed that the stabilization process in all the four treatments studied is comparable, and the final quality of the composts was adequate for agricultural use.
Influence of fertilizer application on biomass yield and nutritional quality of Mustard Spinach (Florida) Broadleaf in South Africa
(2020) Seetseng, K.A.; Gerrano, A.S.; Mavengahama, S.; Araya, H.T.; Du Plooy, C.P.
Mustard Spinach (Florida Broadleaf) is an indigenized leafy vegetable grown in Southern Africa. It is a good source of vitamins and mineral nutrients. An understanding of its response to fertilizer application is important in developing cultural practices for improved yield of the crop. Furthermore, improving fertilizer use efficiency such as nitrogen (N), phosphorus (P) and potassium (K) would result in improving cropping system. Therefore, a field experiment was conducted in 2010 and 2011 winter cropping season to determine the influence of NPK applications and their interactions on biomass yield and nutritional values of Mustard spinach. A randomized complete block design replicated four times were used for the experiment. ANOVA showed significant variation among the treatments. The values for total fresh biomass yield ranged from 252–4,510 and 820–4,982 kg ha-1 in 2010 and 2011 cropping seasons, respectively. Omission of P had 4,510 kg ha-1 of total fresh biomass yield, while omission of K had 4,506 kg ha-1 in the first season. The lowest N content (2.63%) was recorded when nitrogen fertilizer was omitted. Full NPK application increased the content of N and K on the leaf tissues of Mustard Spinach. The highest percentage of dietary fiber was observed when K was omitted. The values recorded for ascorbic acid content varied from 126.94 and 117.42 mg 100g-1 , respectively for both seasons. Iron was more concentrated on the treatments, where K was omitted. Mustard Spinach responded to fertilizer application and the results validated that application of NPK had a beneficial effect on increased production and productivity of the crop tested for small scale farmers.
Characterization of materials used in the manufacture of ceramic tile with incorporation of ornamental rock waste
(2020) Luiz, N.F.; Cecchin, D.; Azevedo, A.R.G.; Alexandre, J.; Marvila, M.T.; Silva, F.C.; Paes, A.L.C.; Pinheiro, V.D.; Carmo, D.F.; Ferraz, P.F.P.; Hüther, C.M.; Cruz, V.M.F.; Barbari, M.
The production of ceramic tiles, such as tiles, has a great environmental impact, either in the extraction of natural raw materials or gas emissions in the burning stages. The use of industrial solid waste in ceramic materials can contribute to the reduction of these impacts, according to the characteristics of solid waste and its interaction with ceramic materials in the processing steps. Thus, this study aimed to characterize the materials needed to make a ceramic tile with incorporation of ornamental rock waste (ORW), thus evaluating its main characteristics regarding the feasibility of this incorporation. The physical characterization of the clays used in the production of ceramic artifacts was performed, and for the waste the mineralogical analyzes were performed, through x-ray diffraction (XRD), microstructure analysis from confocal optical microscopy, after sintering the prototypes and chemical analysis by X-ray spectroscopy (EDX). Soon after the raw materials went through the step of conformation and preparation of the prismatic specimens by the process of extrusion of the ceramic mass, with an incorporation of the ORW in 0% and 15% of the ceramic mass, for its subsequent The prototypes were sintered at three different temperatures (850 °C, 950 °C and 1,050 °C). The specimens were submitted to technological tests of mechanical resistance, water absorption, firing shrinkage and porosity to evaluate the incorporation viability. The results indicated the presence of quartz particles in all raw materials, and also that the clays of the study region are predominantly kaolinitic. The presence of these materials in the ceramic masses directly influences the micrographs, because they result in the formation of liquid phase, inert particles that can turn the site into a stress concentration point and when incorporated in the ORW the specimens met the technical specifications of the Brazilian standard for application on ceramic tiles. The results found in the technological tests carried out, that the incorporation of 15% of ornamental rock waste in both clays did not affect the tile properties, indicating the feasibility of incorporating this waste in civil construction, minimizing the impacts generated.
Lighting source as cause of changes in cucumbers’ physiology and morphology
(2020) Alsiņa, I.; Dubova, L.; Dūma, M.; Erdberga, I.; Augšpole, I.; Sergejeva, D.; Avotiņš, A.
The demand of fresh fruits and vegetables is growing. Therefore cultivation of them is essential all year round. The growth in the dark period of a year is not imaginable without artificial lighting sources. Therefore the experiments were carried out to investigate the effects of three different lighting sources on the growth of cucumbers at the early stages of development. Plants were grown in the polycarbonate greenhouse under three different lighting sources: Led cob Helle top LED 280, induction lamp and high pressure sodium lamp Helle magna. Cucumbers were grown in 16h photoperiod with PAR at the tips of plants 200 ± 20 µmol m-2 s -1 . Plant growth parameters, specific leaf area, pigments, phenols and flavonoids content in leaves, leaf light reflection parameters were determined. Results showed that cucumber plants grown under Led cob Helle top LED 280 in average were smaller, with less chlorophyll, carotenoids and phenols, but leaves have higher chlorophyll a and b ratio and specific leaf area in comparison with traditionally used in greenhouses High Presure Sodium Lamps (HPSL). Cucumber plants grown under Induction lamp in average were shorter, but with larger leaf area, with higher chlorophyll and carotenoids content, but decreased phenols content in comparison with HPSL. Lichtenthaler index 1 (LIC1) and NDVI are useful for assessing the physiological state of cucumber plants. Despite the fact that the plants grow well and develop normally under all lamps, the results show that sodium lamps are the most suitable for cucumbers. Further research is needed to adjust LED lighting for cucumber cultivation.

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