2,198 research outputs found
Effect of different fertilizers on the microbial activity and productivity of soil under potato cultivation
This study was conducted to evaluate the effect of the application of different rates of mineral nitrogen, well rotten farmyard manure and Klebsiella planticola SL09- based microbial biofertilizer (enteroplantin) on the count of soil microorganisms (total microbial count, counts of Azotobacter, oligonitrophilic bacteria, fungi and actinomycetes), stem height and yield of potato. The experiment was set up as a randomized block design in four replications at the experimental field of the Biotechnical Faculty, Podgorica in 2008. Potato cultivar Kennebec was used as the test plant. The trial involved six treatments: non-fertilized control; N1 treatment with 100 kg/ha CAN (calcium ammonium nitrate, 27% N); N2 treatment with 200 kg/ha CAN; N3 treatment with 300 kg/ha CAN; treatment with Enteroplantin– K. planticola SL09-based biofertilizer; and treatment with 30 t/ha solid well rotten farmyard manure. The results obtained suggested that well rotten farmyard manure induced the highest increase in microbial counts, potato yield and stem height. A similar effect on all microorganisms, except actinomycetes and fungi was seen with the use of K. planticola SL09-based biofertilizer. The potato yield and stem height obtained with the use of 300 kg/ha CAN was non-significantly higher than that of 200 kg/ha CAN treatment, with the count of the soil microorganisms tested been significantly reduced.Key words: Biofertilization, microorganisms, soil, manure, mineral nitrogen, potato, yield
Radiation Hardness of Thin Low Gain Avalanche Detectors
Low Gain Avalanche Detectors (LGAD) are based on a n++-p+-p-p++ structure
where an appropriate doping of the multiplication layer (p+) leads to high
enough electric fields for impact ionization. Gain factors of few tens in
charge significantly improve the resolution of timing measurements,
particularly for thin detectors, where the timing performance was shown to be
limited by Landau fluctuations. The main obstacle for their operation is the
decrease of gain with irradiation, attributed to effective acceptor removal in
the gain layer. Sets of thin sensors were produced by two different producers
on different substrates, with different gain layer doping profiles and
thicknesses (45, 50 and 80 um). Their performance in terms of gain/collected
charge and leakage current was compared before and after irradiation with
neutrons and pions up to the equivalent fluences of 5e15 cm-2. Transient
Current Technique and charge collection measurements with LHC speed electronics
were employed to characterize the detectors. The thin LGAD sensors were shown
to perform much better than sensors of standard thickness (~300 um) and offer
larger charge collection with respect to detectors without gain layer for
fluences <2e15 cm-2. Larger initial gain prolongs the beneficial performance of
LGADs. Pions were found to be more damaging than neutrons at the same
equivalent fluence, while no significant difference was found between different
producers. At very high fluences and bias voltages the gain appears due to deep
acceptors in the bulk, hence also in thin standard detectors
Improving the quality of Al-alloys hot forging
Aluminium forgings provide the following advantages: high strength and low weight, good corrosion resistance (for most aluminium alloys), the fibre (grain) structure can be arranged to correspond to the main loading direction leading to high strength and fatigue properties. High precision forgings are designed keeping the following aspects in mind: increasing the accuracy of the component, increasing the fatigue strength, reducing the mass of the component, reducing the amount of machining and increasing the economy. This paper systematically discusses the parameters influencing the accuracy of forgings and forging tool life. Detailed characteristics of alloys AlZnMgCu1.5 (EN-AW 7075) for forging are described. By using the software Simufact. Forming for real part and production conditions, appropriate numerical modelling and recommendations for improved manufacturing have been made.The authors wish to acknowledge the financial support from the Ministry of
Education and Science of the Republic Serbia through the project TR 34002.Publishe
Співвідношення навчання і виховання у філософії педагогіки Памфіла Юркевича
24th General Meeting of the European-Grassland-Federation -- JUN 03-07, 2012 -- Lublin, POLANDWOS: 000361159300041Italian ryegrass monoculture and mixtures with red clover (sowing ratios 75:25%, 50:50% and 25:75%) were established in the spring of 2008 at the Institute for Animal Husbandry, Belgrade, with the aim to analyse the possibilities of managing the N supply. There were four N rates for Italian ryegrass monoculture: 0, 100, 150 and 200 kg ha(-1), whilst no N fertilizer was applied to the mixture plots. The trial was carried out during 2008-2010 and the highest total DM yield was obtained with 200 kg N ha(-1), similar to that of the ryegrass-clover mixtures. Ryegrass contributed less to the total yield in the mixtures, because it had lower ratios in the structure of swards than those used at sowing. An Italian ryegrass-red clover sward may have advantages over a pure Italian ryegrass sward fertilized by high rates of N, providing high yield with a more sustainable land-use system.Kuhn, Ministerstwo Rolnictwa Rozwoju Wsi, Lubelski Wegiel Bogdanka S A, Karol Kania Synowie, Rolimpex, Dept Rolnictwa Srodowiska Urzedu Marszalkowskiego Wojewodztwa, Lubelskiego, Linia Hutnicza Szerokotorowa, Powiat Bilgorajski, Centinas, DSV Polska, Perla Browary Lubelskie, Lubella, Uniwersytet Przyrodniczy w Lublinie, Miasto Lublin, Apis, Herbapol Lublin S A, OSM Krasnystaw, Powiat Krasnostawski, Powiat Lubelski, Powiat Krasnystaw, Lubelska Izba Rolnicza, Gmina Krasnystaw, Urzad Miasta Krasnysta
Numerical modeling of ironing process
Based on comprehensive experimental research and physical modeling of ironing, and detailed study of the material characteristics of the work piece and tool, as well as investigation of the contact friction conditions and measuring temperature generated by this contact friction, we were able to conduct a set of "numerical experiments" using finite element method implemented in the software Simufact.forming. The goal of numerical modeling was to use 3D visualization of the process, especially in deformation zone, to present strain, stress, velocity, and temperature fields which will enable more detailed analysis of the physics of the process. For that purpose a nonlinear FE approach is applied, using solid 3D finite elements, which are optimized for metal forming simulations. This allows obtaining accurate simulation results with the evaluation of changes in the sheet thickness, the effects of residual stress and recurrent elastic strains. Numerical modeling of the process, as well as results of FE analysis have allowed us to obtain important information about the ironing process such as the stress at the wall, strains, deformation forces, generation of temperature in the work piece as a result of plastic strains and the influence of contact friction and transfer of this temperature it to the die. All of these output parameters are evaluated depending on the angle of the die, the forces on the holder, lubrication conditions and the strain rate, analogous to the plan of experiments in physical modeling.Publishe
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