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The study aim was to determine the optimal gamma irradiation dose for mutation breeding in Triticum turgidum ssp. durum L. Root, shoot and seedling growth, as well as the efficiency of energy conversion into growth were determined to examine the growth retardation effects of gamma irradiation that are the result of DNA damage (bridges, ring chromosomes, micronuclei, incomplete mitosis) in Triticum turgidum ssp. durum L. The kernels were irradiated with doses of 50, 150, 250 and 350 Gy using a 60Cobalt gamma-ray source. The kernels were placed in germination paper at 25 °C to grow for a 132 h period for the determination of shoot and root growth and the efficiency of energy conversion into growth. Root tips were collected and fixated over a 47.5 h growth period for the determination of the chromosomal abnormalities and incomplete mitosis. The control differed highly significantly (p < 0.01) from irradiated samples at all doses in root growth and from 250 to 350 Gy samples in shoot growth and the efficiency of energy conversion into growth. There was a highly significant (p < 0.01) increase in the number of bridges and micronuclei between 50 Gy samples and samples irradiated with the higher irradiation doses while 50 Gy samples differed only from 250 and 350 Gy samples regarding ring chromosomes and interphase cells with incomplete mitosis. Root and seedling growth on the one hand and the efficiency of energy conversion into growth on the other were found to be measuring different effects of gamma irradiation on plant growth. The latter was used for the determination of the optimal dose for mutation breeding as 155.52 Gy. [ABSTRACT FROM AUTHOR]

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The analysis and generalization of the results from studies of high-voltage electrochemical explosions (HVECE) proceeding under various conditions driven by special aspects and needs of the existing HVECE-based discharge-pulse technologies were carried out. A methodology to calculate combined energy sources is proposed in relation to the needs of various discharge-pulse technologies using a high-voltage electrochemical explosion. Based on the analysis of the results of experimental studies, the advantage of using a high-voltage electrochemical explosion with a controlled input of electrical energy into the discharge channel was substantiated. An algorithm was developed to calculate the parameters of a combined electric-discharge source of a controlled HVECE and the required mass of the exothermic composition that provides the energy characteristics specified by a specific discharge-pulse technology. The results of testing the developed calculation algorithm are presented that confirm the possibility of its use for engineering calculations of combined power sources with a controlled input of electrical energy into the discharge channel. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The portfolio of the automotive market appears more and more low-emission and zero-emission propulsions in vehicles. This is the result of measures taken to limit or even eliminate the emission of harmful substances into the atmosphere generated by vehicles. The article covers issues related to energy conversion in automotive drive systems currently offered by automotive manufacturers. Standard, hybrid, hybrid plug-in, electric and fuel cells drive system were analyzed. Attention was drawn to the chain of energy transformations related to each of the analyzed drive systems. The efficiency of the presented vehicle drive systems was analyzed. General conclusions were formulated regarding the method of analyzing energy changes related to the operation of automotive propulsion systems. The article reviews selected author's own works on hybrid and hydrogen propulsions. [ABSTRACT FROM AUTHOR]

The study was conducted to determine whether the efficiency of energy conversion into growth can be used as an indicator for the determination of the optimal gamma irradiation dosage for mutation breeding. To meet this objective, embryo growth, shoot growth, root growth, mobilization of food reserves, respiration and energy conversion were studied in gamma-irradiated wheat Triticum monococcum L. cultivar Einkorn kernels. Kernels were exposed to 50, 150, 250 and 350 Gy and germinated. Kernels were collected 12 h after onset of imbibition and then every 12 h until 168 h. Irradiated seed demonstrated retardation in all parameters, which increased as the gamma irradiation dosage increased. For the most, dosage and time, as well as dosage by time interaction were highly significant. Root growth appeared to be the most sensitive to gamma irradiation, followed by shoot growth, mobilization of food reserves and efficiency of energy conversion. Full recovery of the efficiency of energy conversion took place at 50 Gy, with an increase in inefficiency with an increase in dosage. The point where full recovery of efficiency of energy conversion into growth gives way to incomplete recovery (100 Gy) is in line with the suggested dosages for practical mutation breeding in Triticum monococcum L. by the FAO/IAEA and is therefore an ideal indicator for predicting the dosage that will be optimal for plant mutation breeding.

In this study, we discussed the state-of-art in global energy industry in a historical retrospective and the forecast of its development for the next 25 years. At least in the nearest quarter of a century, the main source of primary energy will remain the chemical energy of different hydrocarbon fuels, including natural gas, coal, oil, and biofuels. In this context, of current importance becomes the problem of more rational utilization of produced energy. We analyzed the basic physical constraints that define a maximum efficiency of energy conversion and utiliztion of primary energy sources. [ABSTRACT FROM AUTHOR]

In this paper we determine the physical conditions ensuring that the efficiency of a thermoelectric nanowire with two temperatures is optimal. We consider the case in which the entropy for unitary volume depends on the equilibrium variables only, and the case in which such a quantity depends on the dissipative fluxes, too. We prove that in these two different situations the conditions of optimal efficiency are different. [ABSTRACT FROM AUTHOR]

An alternative to traditional solar collectors with absorbers made of metal or plastic can be panels which have their whole structure made of ceramics. The paper presents the results of the testing of ceramic solar collectors. The experimental research was carried out in summer 2016 in normal operating conditions. Rise in temperature of the fluid flowing through the collector was measured. The maximum value of this parameter did not exceed 7.5 °C and the maximum power output extracted from 1 m 2 of the ceramic solar collector under test was equal to 650 W/m 2 . The thermal characteristic of ceramic solar collectors was determined as the relationship between efficiency and the reduced temperature difference. The straight line corresponding to this characteristic is described by zero-loss collector efficiency coefficient equal to 0.8332 and heat loss coefficient equal to 16.332. Based on the analysis of the test results, it can be concluded that, in spite of some disadvantages, ceramic collectors can compete with traditional solar panels currently available on the market. [ABSTRACT FROM AUTHOR]

The paper presents a novel concept of multiphase boost converter (MPBC) with high efficiency of energy conversion. The new topology of MPBC is compared with conventional single-phase boost converter (SPBC). It is shown that almost whole input energy from photovoltaic module entering to the proposed MPBC is utilized more effectively in comparison with conventional SPBC. This effective energy utilization is ensured by suitable algorithm of switches control. Modeling, simulation and experimental results are given. Subsequently the laboratory models of SPBC and MPBC were built and experimental results were obtained to confirm the simulation results. Also the control module of MPBC was designed, simulated and built to ensure the correct operation of proposed converter.

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F1-ATPase is a rotary motor made of a single protein molecule. Its rotation is driven by free energy obtained by ATP hydrolysis. In vivo, another motor, Fo, presumably rotates the F1 motor in the reverse direction, reversing also the chemical reaction in F1 to let it synthesize ATP. Here we attempt to answer two related questions, How is free energy obtained by ATP hydrolysis converted to the mechanical work of rotation, and how is mechanical work done on F1 converted to free energy to produce ATP? After summarizing single-molecule observations of F1 rotation, we introduce a toy model and discuss its free-energy diagrams to possibly answer the above questions. We also discuss the efficiency of molecular motors in general. [ABSTRACT FROM AUTHOR]

Objective: Oxygen consumption (MVO2) of stunned myocardium is relatively high compared to, and poorly correlated with, systolic contractile function. The aim of this study was to investigate whether an increased afterload dependency, induced by the decreased contractility of the stunned myocardium, contributes to the large variability in the mechanical efficiency data. Methods: In 13 anaesthetised open thorax pigs undergoing two cycles of 10 min occlusion of left anterior descending coronary artery and 30 min reperfusion, segment shortening, the slope of end systolic pressure segment length relationship (Ees), external work (EW, derived from the area inside the left ventricular pressure segment length loop), the efficiency of energy conversion (EET, = × 100%, where PLA = total pressure-segment length area), mechanical efficiency (), and their dependency on left ventricular end systolic pressure (Pes) were determined before and after induction of stunning, and during subsequent inotropic stimulation with dobutamine (1 and 3 μg·kg−1·min−1 over 15 min). Results: The stunning protocol not only caused significant decreases in segment shortening, external work, energy conversion efficiency, and but also increased the afterload dependency of these variab Before stunning an increase in Pes from 100 to 160 mm Hg decreased segment shortening from 18(SEM 1)% to 14(2)% (P > 0.05) and increased external work from 206(18) to 254(32) mm Hg·mm (P < 0.05). After induction of stunning the same increase in Pes caused a decrease in segment shortening from 9.5(1.8)% to −4.6(2.1)% (P < 0.05) and in external work from 149(21) to −11(10) mm Hg·mm (P < 0.05). The afterload dependency of the PLA was not altered by stunning, but the afterload dependency of energy conversion efficiency increased, since efficiency decreased from 67(3)% to 59(5)% as Pes was increased from 100 to 160 mm Hg before stunning, but from 57(5) to −7(5)% after induction of stunning (P < 0.05). Furthermore, the same increase in Pes resulted in an 8% decrease of before stunning and 107% after inducti stunning. Infusion of dobutamine not only restored segment shortening, external work, energy conversion efficiency, and of the stunned myocardium, but also attenuated their afterload dependency to levels. Conclusions: Myocardial stunning increases the afterload dependency of segment shortening, external work, energy conversion efficiency, and mechanical efficiency, which can be attenuated by inotropic stimulation with dobutamine. However, the decrease in left ventricular end systolic pressure, which accompanies the induction of stunning, counteracts the decrease in these variables. These two mechanisms can explain most of the reported scatter in mechanical efficiency. [ABSTRACT FROM PUBLISHER]