2017

Selle valdkonna püsiv URIhttp://hdl.handle.net/10492/5357

Sirvi

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Evaluation of smart economy development in the RIGA planning region (LATVIA)
(2017) Rivža, B.; Āzena, L.; Rivža, P.
To evaluate the potential development of smart economy in the Riga planning region (henceforth – RPR), it is important to understand the present situation in the region, its specificity, and role in the context of provisional future trends. Two approaches have been employed in the present study to evaluate the situation on a regional level. One includes the collection and comparison of the basic economic development indicators, whereas AHP method has been used in the second approach, where 5 experts expressed their opinion on the options of potential development of smart specialisation in the RPR. RPR as a capital city region is pronouncedly monocentric, with Riga city as its socioeconomic core that develops a wide network of functional ties, and creates a home for the part of the society that works in Riga, but lives in the adjacent suburban territories – Pieriga. Traditionally the basic indicators of development include only the demographic and economic indicators. Sometimes these results are not objective, do not describe the potential for development, but clearly show the inequal social and economic situation in the region. To characterise the economic development in the RPR, we will include the economic profile data, statistical data and expert opinions on the population, regional government, state and EU influence on the development of the Pieriga region smart specialisation.
Chemical composition of seeds and green beans of common bean varieties, breeded in Omsk State Agrarian University under conditions of southern forest-steppe zone of Western Siberia
(2017) Kazydub, N.; Pinkal, A.; Marakayeva, Т.; Kuzmina, S.; Korobeinikova, M.; Kotsyubinskaya, O.
The article considers the biochemical composition of green beans and seeds of common beans varieties, breeded in Omsk State Agrarian University named after P.A. Stolypin (OmSAU). The research was conducted in 2014–2016. Varieties of locally breeded beans, in comparison with the standards, have advantages in the content of protein, zinc, iodine, calcium, iron, sugar; green bean technological properties and tenderizing of seeds during cooking, which becomes an indispensable component of the diet.
Results of fifteen-year monitoring of winter oilseed rape (Brassica napus L.) production in selected farm businesses of the Czech Republic from the viewpoint of technological and economic parameters
(2017) Šařec, O.; Šařec, P.
The paper presents field trials focused on technological and economic comparison of conventional tillage (CT) and reduced tillage (RT) technologies of soil cultivation and drilling of winter oilseed rape (Brassica napus L.). During fifteen production years starting in 2001/02, trials were set up in 520 fields of around 40 farm businesses located in all of the districts of the Czech Republic. With respect to average seed yields, no significant differences were proved with respect to tillage systems, to the application of organic fertilizers and to the fertilization during sowing. Irregular distribution of trial fields into the individual production areas influenced the outcomes thou. Concerning winter rape seed yields, costs per production unit, and earnings per hectare, the most suitable production area proved still to be the potatoes one, but particularly over the recent period also beet production area. The corn production area produced, despite some exceptions, worst results. Over the fifteen-year time, the average oilseed rape yield of all 520 monitored fields was 3.72 t ha–1 . Reduced tillage attained average yield of 3.73 t ha–1 , i.e. matched almost exactly the one of 3.70 t ha–1 attained by conventional tillage. Unit production costs realized by conventional tillage surpassed by 4.1% those gained by reduced tillage. Related earnings per hectare were on the other hand lower by 17.0%. With respect to fuel and labour consumption, reduced tillage brought significant savings reaching in average 20.2%, respectively 24.0%. In terms of yields, reduced tillage with deeper soil loosening proved repeatedly favourable results.
Legumes in the diet of dairy cows from the economic perspective
(2017) Proskina, L.; Cerina, S.
Based on the experimental data, one can conclude that feed rations may comprise peas var. ‘Bruno’ and faba beans var. ‘Lielplatone’ grown in Latvia, thereby replacing the use of imported soybean cake. After summarising the results of trials, one can conclude that the diets comprising only one kind of legumes (peas or beans) were the most economically efficient, while the highest production efficiency was achieved if incorporating 22–24% ‘Lielplatone’ faba beans into the diet for dairy cows. In Europe and Latvia, foods of animal origin comprise, on average, 45% of the total agricultural output value; an essential role in the production of the foods is played by the supply of protein-rich feedstuffs to the livestock industry. An analysis of the factors influencing productivity in dairy farming shows that a diet is the most important factor that promote or hinder the functioning of the inherited genetic potential. In order to meet the dietary energy, protein and mineral requirements of cows, the cows have to be fed a diet according to their physiological condition. In recent years in many countries, research investigations into protein sources have been conducted, as a high protein content of feedstuff is the most expensive component of a feed ration. For this reason, their use in livestock diets might be economically inefficient and therefore the key focus has to be placed on opportunities to increase the content of protein in domestically produced feeds.
Effect of flame weed control on various weed species at various developmental stages
(2017) Mojžiš, M.; Vitázek, I.; Klúčik, J.
Physical methods of weed control as solarization, mulching, use of electricity, steam and flame are now an alternative in the organically grown crop. Flame weeder already has a wide range of practical use , particularly in the cultivation of vegetables in alternative form without any chemical treatment. Compared to chemical spraying, the use of flame weeder is more expensive, but we can compensate the costs by the added value of bioproducts. The issue of costs affects the wider use of the method in practice, but it may be offset by increased e fficiency of weed control. The correct parameters of flame weeder, such as burner angle, burner height, the gas pressure, speed of weeder as well as the growth stage of the weed, weed species, climate conditions etc., can increase the effectiveness of weed control. Field and laboratory tests carried out in Canada and Slovakia were aimed at verifying the influence of parameters on the effectiveness of flame weed control.
Soil organic carbon in long–term experiments: comparative analysis in Slovakia and Serbia
(2017) Macák, M.; Đalović, I.; Turan, J.; Šeremešić, S.; Tyr, S.; Milošev, D.; Kulina, M.
Soil organic carbon plays an important role in a long-term agroecosystem productivity, in the global C cycle, maintaining a soil nutrient pool and improving its availability. The objective of this study is the assess the impacts of long–term cropping practices on SOC dynamics in Slovakia and Serbia. Soil C sequestration is a complex process that is influenced by many factors, such as agricultural practice, climatic and soil conditions. For the both location the initial SOC decline was followed with the C stabilization and possible increase where proper practices were used. More intensive crop management systems that maintained residue cover provided the greatest benefit towards increasing the quantity of mineralizable nutrients within the active fraction of soil organic carbon (SOC), as well as increasing C sequestration as SOC. Long–term field experiments have contributed significantly to our current knowledge of soil quality and have been used to study the influence of crop management, fertilizer application and tillage practices on SOC content.
Effect of rake angle and cutting speed on energy demands of mulcher with vertical axis of rotation
(2017) Čedík, J.; Pexa, M.; Pražan, R.
The contribution deals with the reduction of agriculture energy demands. For maintenance and treatment of permanent grassland areas, areas left fallow and put to rest the mulching in combination with other workflows (mowing, grazing) is advantageous procedure. As conventional impact grass cutting and chopping is energy demanding procedure, it is proper to reduce the energy demands of such device. In the paper the effect of shape of cutting tool, particularly the rake angle, on energy demands of mulcher with vertical axis of rotation is studied. The effect of cutting speed on energy demands is also verified. The measurement was performed using mulcher MZ 6000 made by Bednar FMT Ltd. with working width of 6 m and three rotors. During the measurement the test rides using the cutting tools with different rake angle and cutting speeds of 105m s-1 , 89 m s-1 and 79 m s-1 were performed. The rake angle of cutting tools were chosen 0°, 15° and 25°. The test area was pasture with permanent grassland. During the measurement the torque and power, transferred through PTO to the machine, fuel consumption and GPS coordinates were measured. From each test ride the samples of grass matter were taken in order to determine the yield and moisture content. It was found that increase of the rake angle up to 25° and decrease of the cutting speed resulted in decrease of the power requirement of the mulcher.
Quality evaluation of local apple varieties: physicochemical and antioxidant proprieties at harvest and after cold storage
(2017) Bartolini, S.; Ducci, E.
A wide apple germplasm is present in Italy in which numerous local genotypes of specific cultivation environment have to be still evaluated for fruit quality attributes. This is the case of a long-established fruit area located in central Italy (Tuscany) where several ancient apple varieties survive with the perspective to be re-introduced for their excellent quality. The objective of this work was to determine over a 2-year period the physicochemical traits, total antioxidant capacity (TAC), and polyphenols (TP) content of three old local apple varieties: ‘Paganina’, ‘Paradisa’ and ‘Rosa’. These characteristics were also assessed after 90 and 150 days at 4 °C cold storage, in normal atmosphere refrigerated cellars. For comparison purpose, the commercial apple cultivar ‘Fuji’ was considered. In general, the old varieties showed valuable quality properties, particularly due to a greater antioxidant power of fruits, although a variability between the two crop seasons, characterized by different weather conditions, was observed. After a dry summer, ‘Rosa’ showed very high TAC and TP values (2-fold higher than other varieties) that, after longperiods of cold storage, markedly decreased. These losses were not so noticeable in the others, suggesting a tendency to maintain a major stability during storage. These findings could meet the preference of demanding consumers for healthier foods who appreciate fresh fruits with protective properties by free radicals scavenging activity. Moreover, farmers who are focused on nearby and niche markets could have interesting in these local varieties to promote their valorization.
Fair Trade and social responsibility – whose duty? Estonian consumers’ attitudes and beliefs
(2017) Riivits-Arkonsuo, Iivi; Ojasoo, Merle; Leppiman, Anu; Mänd, Kristina
This article investigates how the Estonian consumers endorse the idea of Fair Trade (FT) and understand the principles of social responsibility. The article is based on a study on Fair Trade and social responsibility conducted in 2014. The study examined the consumers’ attitudes and beliefs associated with FT and local Estonian agricultural production. The article aims to compare if there are any difference in the beliefs and attitudes among the Estonian consumers towards supporting local farmers and producers versus supporting the FT ideas which benefit the farmers and producers from the Global South. The authors fully recognise that there is no competition among these two groups per se, but the perception exists in the minds of the consumers. The respondents of the nation-wide representative sample (n = 1,007) evaluated the responsibility of different economic agents such as public sector, retailers, suppliers, producers, and consumers. Most of the respondents regarded the principle of social responsibility as giving the priority to local Estonian agricultural production. The Estonian consumers tend to be sceptical about the benefits of FT or the workers and farmers from the developing countries. The awareness and knowledge about FT ideas is not high.
Influence of shape of cutting tool on pressure conditions in workspace of mulcher with vertical axis of rotation
(2017) Čedík, J.; Chyba, J.; Pexa, M.; Petrásek, S.
Nowadays there is laid great insistence on work efficiency improvement. This effort also affects the construction of mowers such as mulchers. Mulching with a vertical axis of rotation is very energy demanding work operation mainly, due to high energy losses. These energy losses, but also the quality of work, are influenced by the airflow and associated conditions of pressure inside the workspace of mulcher. Airflow in the workspace ensures repetitious contact of the truncated forage crops with the cutting edge tool and thus ensures crushing of aboveground parts of plants. The paper deals with the influence of the cutting tool shape on the mulcher’s inside workspace pressure conditions with the vertical axis of rotation. The influence of the trailing edge angle and rake angle on the pressure profile in the mulcher’s workspace with dependence on the rotor speed was examined. Measurements were performed on a laboratory single rotor mulcher model. It was found that in the mulcher’s workspace the vacuum is formed by virtue of the rotary movement of the cutting tools wherein the vacuum increases with rotor speed. The maximum measured vacuum was about 2.4 kPa and from the centre of the rotor towards its circumference almost linearly decreases. Furthermore, it was found that with decreasing trailing edge angle and with increasing rake angle the maximum vacuum decreases. When reducing the angle of the trailing edge from 45° to 25° led to reduction of vacuum of about 0.3 kPa (12.6%).
The content of weed seeds in the soil based on the management system
(2017) Kuht, Jaan; Eremeev, Viacheslav; Talgre, Liina; Madsen, Helena; Toom, Merili; Mäeorg, Erkki; Loit, Evelin; Luik, Anne; Estonian University of Life Sciences
In 2008 an experiment was set up on the field in Eerika experimental station (Estonian University of Life Sciences) as a 5-field crop rotation: barley (Hordeum vulgare L.) with undersown red clover, red clover (Trifolium pratense L.), winter wheat (Triticum aestivum L.), pea (Pisum sativum L.), potato (Solanum tuberosum L.). The objective of the study was to measure the content of weed seeds in the soil and to evaluate the diversity of the species at the beginning of the period of organic production in 2011. In conventional farming systems without fertilizer (Con I) and conventional farming with mineral fertilizer (Con II) herbicides were used for weed control. All the crops in Con II system received P 25 kg ha-1 and K 95 kg ha-1 , but the application rates of mineral nitrogen fertilizer differed. In organic systems (Org I – organic farming based on winter cover crop and Org II – organic farming based on winter cover crop and manure), the winter cover crops (ryegrass after winter wheat, winter oilseed rape after pea, winter rye after potato) were sown after the harvest and were ploughed into the soil as green manure in spring. Organic farming systems (Org II) had a negative effect on the content of weed seeds in the soil (2.0–22.7% less seeds than in other variants). The seeds of Chenopodium album were the most abundant among summer annual weeds and the seeds of Viola arvensis among winter weeds in the soil. Organic farming measures increased the domination of Chenopodium album – the dominance index D’ was increased by 0.09–0.14 compared to conventional variants. The content of seeds of winter weed Viola arvensis in Org II variant was decreased by 82%. The index of species evenness J’ and Shannon Wiener diversity index H’ were lower in organic plots by 0.10– 0.18 and 0.60–0.19, respectively. Org II variants showed the best results based on the decrease of soil weed seed bank and distribution of the weed species.
Risk analysis regarding a minimum annual utilization of combine harvesters in agricultural companies
(2017) Mimra, M.; Kavka, M.
This article presents the results of entrepreneurial risk analysis concerning a minimum annual utilization of harvesters in a company providing agricultural services where a group of combine harvesters is used. Furthermore, this article presents the following analysed key operating parameters with the greatest influence on reaching the minimum annual utilization and performance: the changing market price of mechanized work, the volatile purchase price of the machines, average maintenance costs). Partial profit which an enterprise can reach through operating combine harvesters is directly affected by the level of their annual utilization. Not reaching the minimum annual utilization of combine harvesters would create losses that could result in termination of business activity in the specific field or even insolvency of the company. It is therefore necessary to monitor the key factors which influence the minimum annual usage and in case of negative developments to take timely corrective actions.
Requirements for inserting intercropping in aquaponics system for sustainability in agricultural production system
(2017) Puteri Edaroyati, M.W.; Siti Aishah, H.; Al-Tawaha, A.M.
In recent years, the recirculating aquaponics system has gained high attention and significant popularity for organic vegetables and fruits production which contributes to the sustainable aquaculture for tropical regions. This review aims to summarize the possibility for practicing intercropping in aquaponics to produce high-quality fruits, vegetables and fish without any chemical fertilizer and minimum ecological impact for a sustainable agriculture. Although many studies have addressed about aquaponics for producing high-value crops such as tomato, cucumber, and lettuce, there is still a lack of complete information to support the development of intercropping in aquaponics and limited focus on its commercial implementation. Moreover, this study will focus first on the requirements for inserting intercropping in aquaponics and technical improvements needed to adapt as potential for sustainable food production system to increase productivity around the world, especially in countries have deficiency in water and land resources as well as soil problem like salinity and reduce environmental emissions. Secondly, the insertion of intercropping in aquaponics must be for crops with high value and for crops that can complement together such as tomato with basil and tomato with lettuce. Thirdly, in technical improvement in this study will summarize the strategies and factors that affect the intercropping in aquaponics system such as the nutrients needed for crops under intercropping aquaponics, stocking density and feeding rate which are important to know the concentration of ammonia that is produced and converted to nitrate so that the plants can uptake it. Studying the requirements for inserting and improving intercropping in aquaponics will increase our understanding of needed for new agriculture technique that contributes to the sustainable aquaponics for tropical regions.
Effects of irrigation applied at different growth stages on chickpea yield
(2017) Kirnak, H.; Varol, I. S.; Irik, H. A.; Ozaktan, H.
This study was conducted over the experimental fields of Erciyes University in 2016 to investigate the effects of irrigations applied at different growth stages on chickpea yields. Experiments were conducted in randomized blocks design with 3 replications. There were 7 irrigation treatments as of I1: rainfed, I2: pre-bloom single irrigation, I3: single irrigation at the beginning of blooming, I4: single irrigation at 50% pod set, I5: two irrigations at 50% bloom and 50% pod-set, I6: two irrigations at pre-bloom and 50% pod-set, I7: full irrigation. The amount of applied irrigation water varied between 85.6–323 mm. Plant water consumptions varied between 262 – 569 mm. The greatest yield was obtained from I4 treatment with 273 kg da-1 and the lowest yield was obtained from I1 treatments with 146 kg da-1. It was concluded for chickpea cultivation under deficit water resources conditions that water deficits may be applied at different growth stages except for 50% pod-set period.
Determination of mechanical properties of poppy waste pellets
(2017) Kažimírová, V.; Kubík, Ľ; Chrastina, J.; Giertl, T.
The work deals with evaluation of mechanical properties three types of pellet samples produced fro m poppy waste. The pellets were submitted to compressive loading. The compressive loading curves of dependencies of force on strain and force on time were realised. Certain mechanical parameters were determined, namely the diameter of the sample, length of the sample, force at 10% of strain, force in the first maximum of the force – strain curve, strain in the first maximum of the force – strain curve, modulus of elasticity, force in the inflex point of the force – time and force – strain curves and strain and stress in the inflex point of the force – time and force – strain curves. The work lists correlations of mechanical parameters of individual pellet types. The pellet type 1 made only of ground poppy head mass has shown the best results, the pellet type 3 consisting of ground poppy heads after harvest and waste from sieving of poppy seeds in mass proportion 1 : 1 has shown the worst results.
Improving job satisfaction with different intervention methods among the school personnel in Estonia and Latvia
(2017) Hrenov, G.; Vilcane, I.; Urbane, V.; Tint, Piia
This investigation was carried out in two high schools: one in Estonia (EST1) and one in Latvia (LAT1). The offices EST2 and LAT2 were chosen from the countryside of the both countries. Office EST1 is situated in an atrium-type building for educational and research needs. The second building is mainly for education (auditoriums) and the offices LAT1 are situated on the ground floor. The third and the fourth offices were taken for comparison. Office EST2 is situated in a countryside in an old wooden building; the fourth office LAT2 is located in a new building in Latvian countryside. All together 181 office-workers were involved. At first, the work environment conditions were measured. The ergonomics of workplaces was assessed with ARTtool and Kiva-questionnaire was used to study psychosocial conditions and job satisfaction at computer-equipped workplaces. Occupational hazards were measured to clarify, do the work environment influence on the behaviour and the job motivation and satisfaction of the worker at workplace? After the first questioning of workers using Kiva-questionnaire, the Metal Age programme was implemented and after the intervention, the Kiva-questionnaire was carried out again. The results showed that if the preventive measures for solving the problems at workplace are implemented, and the employers and the employees are trained and consulted using the appropriate programmes, the stress situations could be avoided. The workers in all offices were confident that the discussion about the problems is very important as the work with computers is intensive and there is a very short time to communicate with each other. The educational work is also stressful.
The effect of bedding amount on gas emissions from manure during storage
(2017) Šimon, J.; Vegricht, J.; Bradna, J.
One of the major agricultural pollutants of environment is manure from livestock. We focused on dairy cows kept in the barns with straw bedding commonly used in the Czech Republic. We tested the hypothesis that the amount of bedding used daily relative to the number and size of animals kept has a significant effect on the emissions of gases from manure stored in a manure pile. In the experiment, a group of 10 dairy cows of Holstein and Czech Red Pied breed was housed in a stable bedded with various amounts of wheat straw (4–10 kg/livestock unit per day). The manure was removed from the stable after 48 h and mixed was stored in cubic containers with drain floor allowing measurement of manure leachate release. For 50 days we measured weight, volume, weight of manure leachate and manure temperature. Decreasing stored manure weight can be attributed to release of manure leachate and emissions of gases, primarily water vapor, as a result of microbial activity and increased temperature in the manure during storage. Using the calculated model, we found that daily production of emissions of water vapor and other gases was related to bedding amount in a statistically significant manner (P < 0.001). The cumulative amount of gas emissions grew rapidly in all treatments. Also total amount of emissions was related to bedding amount in a statistically significant manner (P = 0.004). We also found the relationship between internal manure temperature and the logarithm of the amount of emissions produced to be statistically significant (P < 0.001).
The advantage of Decision Support System for managing spring barley disease in Estonia
(2017) Sooväli, Pille; Koppel, Mati; Lauringson, Enn; Talgre, Liina
A Decision Support System (DSS) I - Taimekaitse focusing on use of timely applied and reduced fungicide rates in control of cereal diseases has been tested in field trials since 2003 . We compared the conventional treatment and the DSS - based spray practices in 18 field trials in five agricultural locations over 7 - year period. Efficacy of the control of net blotch caused by Pyrenophora teres (Drechsler, am Drechlera teres Sacc. Shoem), the main fungal disease in spring barley has been tested to determine the economic advantage of DSS use. Compared with the conventional spray practices, the advantage I - Taimekaitse resulted in reduction of application doses by 30 to 60% of the registered rate. According to I - Taimekaitse , the fungicides were applied mainly between heading and flowering growth stages (GS 55 – 65), whereas traditional routine spraying is commonly made at booting (GS 37 – 49) . The experiment clarifies the cost - benefit of using DSS - based approach in barley disease management with average yield increase above the control in 12.8% and above the conventional treatment in 14.1%. I - Taimekaitse gave competitive disease control and average yield output reduction compared with conventional practice by 9%. In general the Treatment Frequency Index applied in conventional treatment was 0.65 and in DSS 0.41. Although the cost of treatment expense in DSS was 20% less compared with conv entional practice, the performance of conventional used spray practices was outstanding in economic return.
Theoretical research into the stability of motion of the ploughing tractor-implement unit operating on the ‘push-pull’ principle
(2017) Bulgakov, V.; Adamchuk, V.; Nadykto, V.; Kistechok, O.; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
The reduction of power consumption in the ploughing operations can be achieved by way of improving the grip properties of the implement-carrying tractors, which is facilitated by setting up ploughing units for operation on the ‘push-pull’ principle. The aim of the current research is to substantiate the set-up and parameters of the ploughing unit with a front-mounted plough basing on the theoretical investigation of the stability of its motion in the horizontal plane. The methods of research include obtaining the amplitude- and phase-frequency response characteristics of the dynamic system in order to analyse the stability of its motion under the action of external statistically random perturbations. Also, the methods of software development and PC-based numerical computation are applied. The results of the study prove that the increase of the ploughing unit’s travel speed results in the considerable rise of the gain of the amplitude of the tractor’s heading angle oscillation in response to the oscillation of the angular displacement of the front-mounted plough in the horizontal plane. The phase-frequency response displays the same behaviour, changing substantially together with the unit’s travel speed. Raising the coefficient of resistance to tyre slip of the tractor’s rear wheels from 100 to 130 kPa and the front wheels from 140 to 175 kPa results in a minor decrease of the amplitude of oscillation of the tractor’s heading angle φ. The ploughing unit has the best response to the input effect, i.e. the oscillation of the front-mounted plough’s angular displacement βp, when it operates using the 1+5 combination. The increase of the number of front-mounted plough bodies from 1 to 3 results in the substantial growth of the tractor’s heading angle oscillation amplitude. Taking into account the way, in which the ploughing unit as a dynamic system responds to the input perturbance, the increase of its travel speed can be restricted not by the condition of its motion stability, but solely by the agrotechnical requirements applied to such a process operation as ploughing. The ploughing unit’s motion stability substantially improves in case of higher air pressure in the tyres on the tractor’s front and rear wheels. This effect is especially pronounced in the perturbance oscillation frequency range (0...1.5 s –1 ) that covers the main part of its dispersion.
Dimethyl ether as a renewable fuel for diesel engines
(2017) Zeman, P.; Hönig, V.; Procházka, P.; Mařík, J.
The area of automotive fuel, or fuel components, which can be produced from biomass also includes dimethyl ether, otherwise known as DME. The issue of the use of DME as a fuel is one which has been monitored until recently. Biomass can also be used as the raw material for the production of DME. DME has therefore replaced the previously-used CFCs (chlorofluorocarbons), which are now banned for their role in dangerous levels of ozone depletion. With regard to its physical properties and combustion characteristics, it is currently expected that DME will soon apply significantly as a fuel in the municipal sector and in households, and as an alternative fuel for motor vehicles with diesel engines. DME is a suitable fuel for diesel engines and can be considered as one of the most promising diesel fuel replacements. DME is a suitable fuel for diesel engines mainly due to its low self-ignition temperature and good cetane figures. It is well miscible with most organic solvents and because the polar solvent is water-immiscible. The advantage is its high levels of purity, and its being free of sulphur, nitrogen, or metals. The physical properties of DME are very similar to the physical properties of LPG. DME requires relatively complex and costly fuel accessories, but the original compression ratio of the diesel engine is maintained. A diagram of the fuel system is illustrated in the paper. The paper analyses the dependence of vapour pressure on temperature, the dependence of the density on temperature, kinematic viscosity, the flash point, the boiling point, and the solubility of water. The objective is to evaluate this interesting energy source for applications in diesel engines.

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