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The aim of the research is to reveal the biological removal, balance and coefficient rates of nitrogen, phosphorus and potassium use from soil, organo-mineral fertilizers and microbiological concentrates by tomato and sweet pepper in the conditions of Ararat Plain of Armenia. Field experiments were carried out in 2017-2019, on typical irrigated meadow brown soils in triplicate. It has been established that at tomato yields of 50-75 t ha-1, the biological removal of nitrogen ranges from 110 (without fertilizers) to 178 kg ha-1 (N150P80), P2O5: 61-89, K2O5: 166-289 kg ha-1, and at pepper yields of 23-32 t ha-1, respectively - 55-76, 38-49 and 77-106 kg ha-1. Tomato utilization rates from the soil (unfertilized version) are: N: 118, P2O5: 37, K2O: 8%, and the negative balances are respectively: 107, 67 and 109 kg ha-1, similar data for pepper were recorded at: N: 59, P2O5: 23, K2O: 4% and 52, 44, 20 kg ha-1. From fertilizers, tomato absorbs 27-45% nitrogen, 11-48% P2O5 and 48-72% K2O with negative balances (N: 15-55, P2O5: 14-76, K2O: 34-79 kg ha-1), in poultry litter the balance P2O5 = + 94.2 kg ha-1. For pepper, however, these data were respectively amounted to: N: 6-14, P2O5: 10-15, K2O: 9-20%, and the balances were positive. Microbiological concentrates (Azoto + phosphate Barvar) showed poor effectiveness as compared to organo-mineral fertilizers. It was also found that the lower the amount of a mobile element in the soil, or in the fertilizer dose, the higher its utilization rate and vice versa. [ABSTRACT FROM AUTHOR]

In conditions of semi-desert soil zones of Armenia (1,130 m high above the sea level) the agro-biological properties of groundnut varieties Lia, Virginia, Mocket, TMV 3, Sevahatik (Black Seed) and Chinese have been studied with the aim of selecting their best options for further regionalization in the piedmont zones. The field experiments were conducted in 2020-2022. The calculations and laboratory analyses have indicated that the field germination capacity of the mentioned varieties is rather high fluctuating within the range of 77.5-81.0%, whereas the weight of 1,000 grains equaled to 515-545 g, the average yield - 2.77-3.33 t ha-1, the total nitrogen in the grains were 4.39-4.61%, crude proteinւմ (per 5.70 factor of nitrogen) - 25.02-26.28%, total sugar contents - 14.11-16.63%, and fat content - 44.8-48.0%. The Mocket and Chinese varieties were distinguished by their yield capacity and qualitative indices of the yield and thus, the latter have been recommended for the cultivation in the farm households of the mentioned zone. [ABSTRACT FROM AUTHOR]

The results of the simulation of heat propagation processes in the multilayer detection pixel of a single-photon thermoelectric detector consisting of heat sink (Bi-2223), thermoelectric sensor (CeB6), absorber (Bi-2223), and antireflection layer (SiO2) arranged in series on sapphire substrate (Al2O3) are presented. The design of the detection pixel without an antireflection layer is also considered. Simulation of the processes of absorbed photons heat transfer is carried out based on the equation of heat propagation from a limited volume. The cases of absorption of photons with energies of 0.8–1000 eV in detection pixels with a surface of 4 and 1 µm2, different thicknesses of absorber and sensor at a fixed operating temperature of the detector of 9 K are studied. Temporal dependences of voltage arising on the sensor, the equivalent power of Johnson and phonon noise are investigated, the signal-to-noise ratio is calculated, and the ways to increase this parameter are proposed. [ABSTRACT FROM AUTHOR]

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The aim of the research is to identify the extent of production removal of the main nutrient elements in the irrigated grain-growing lands of Armenia, to optimize the norms of organo-mineral fertilizers, to stabilize the yield of plants and prevent dehumification. The field experiments were carried out in the conditions of the Ararat Valley on winter wheat and barley in 2020-2022. The production removal of nitrogen by 5-7 t ha-1 grain of winter wheat and 9.6-13.3 t ha-1 straw varies between 155-247, P2O5: 60-88, K2O: 134-197 kg ha-1, and the amounts removed by barley grain 4.5-6.5 t ha-1 and straw 6.9-9.7t ha-1 were 122-194, 49-77 and 106-159 kg ha-1, respectively. The amounts of nitrogen and potassium production removal from plant crops are about 2 times higher than the doses of applied fertilizers, and the amount of phosphorus is almost balanced by these doses. [ABSTRACT FROM AUTHOR]

The results of modelling of heat propagation processes in the five-layer detection pixel of a thermoelectric single-photon detector after absorption of several photons are presented. We have considered the absorption of photons in the detection pixel with a surface area of 10 × 10 μm2 and various thicknesses of the antireflection layer (SiO2), absorber (W), thermoelectric sensor (FeSb2), heat sink (W), and substrate (Al2O3). To simulate of heat transfer processes the technique based on the equation of heat propagation from a limited volume is used. The cases of simultaneous absorption of several photons at a length of 1 μm of the absorber surface are investigated. It is shown that it is possible to determine the number of absorbed photons up to 8. [ABSTRACT FROM AUTHOR]

The aim of the research is to study the biological removal of the main nutrient elements from the most common technical grape varieties, as well as from apricot and peach plantations in the farms, situated on semi-desert natural soils of Armenia, to identify the extent of their input and losses due to natural factors and to calculate the balance associated with the soil conservation system in the absence of comprehensive fertilization. In the inter-row spaces of all fruit plantations and even vineyards of the republic, grass cover of productive significance has been established (4.5-6.5 t ha-1 yield of air-dry grass), through which the removal of nutrient elements is 2-3 times higher than the biological removal through trees and vines. The research was conducted in 2015-2020, in the grape, apricot and peach plantations of the semi-desert natural zone of Armenia (Armavir region), where the irrigation norm is 5,000 m³ ha-1, and the atmospheric precipitation is 256 mm, through which 40 kg ha-1 N, 2 kg ha-1 P2O5, and 44 kg ha-1 K2O enter the soil. The losses due to erosion and washing away are N - 12 kg ha-1, P2O5 - 7 kg ha-1, K2O - 75 kg ha-1. The balance of nutrient elements in all plantations is negative, nitrogen in plantations with industrial grass cover is 154, P2O5 - 52, K2O - 311, and in the system of black fallow - 15, 16 and 85 kg ha-1, respectively. The negative balance of nitrogen in apricot and peach plantations is 121, P2O5 - 44, K2O - 296 kg ha-1. [ABSTRACT FROM AUTHOR]