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The paper provides an assessment of the current wind energy potential in Ukraine, and discusses developmental prospects for wind-hydrogen power generation in the country. Hydrogen utilization is a highly promising option for Ukraine's energy system, environment, and business. In Ukraine, an optimal way towards clean zero-carbon energy production is through the development of the wind-hydrogen sector. In order to make it possible, the energy potential of industrial hydrogen production and use has to be studied thoroughly.Ukraine possesses huge resources for wind energy supply. At the beginning of 2020, the total installed capacity of Ukrainian wind farms was 1.17 GW. Wind power generation in Ukraine has significant advantages in comparison to the use of traditional sources such as thermal and nuclear energy.In this work, an assessment of the wind resource potential in Ukraine is made via the geographical approach suggested by the authors, and according to the «Methodical guidelines for the assessment of average annual power generation by a wind turbine based on the long-term wind speed observation data». The paper analyses the long-term dynamics of average annual wind speed at 40 Ukrainian weather stations that provide valid data. The parameter for the vertical wind profile model is calculated based on the data reanalysis for 10 m and 50 m altitudes. The capacity factor (CF) for modern wind turbine generators is determined. The CF spatial distribution for an average 3 MW wind turbine and the power generation potential for the wind power plants across the territory of Ukraine are mapped.Based on the wind energy potential assessment, the equivalent possible production of water electrolysis-derived green hydrogen is estimated. The potential average annual production of green hydrogen across the territory of Ukraine is mapped.It is concluded that Ukraine can potentially establish wind power plants with a total capacity of 688 GW on its territory. The average annual electricity production of this system is supposed to reach up to 2174 bln kWh. Thus, it can provide an average annual production of 483 billion Nm3 (43 million tons) of green hydrogen by electrolysis. The social efficiency of investments in wind-hydrogen electricity is presented.  相似文献   
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OBJECTIVE: To study the determinants and nature of dietary underreporting in a free-living population. DESIGN: Cross-sectional study of nutritional and behavioural characteristics. SUBJECTS: 1030 weight-stable subjects, 501 women and 529 men older than 15 y, included in the Fleurbaix Laventie Ville Santé study. MEASUREMENTS: Dietary intake was assessed using a 3 dy dietary record. Self assessed body weight and height were also recorded. Behavioural and socio-economic data were obtained from a questionnaire. Underreporters were defined as people with a reported ratio of energy intake to estimated basal metabolic rate lower than 1.05. RESULTS: Underreporting concerned 16% of the population and was significantly more frequent in obese than in non obese subjects (P < 0.001). Underreporting was significantly associated with a high socio-professional class (P < 0.05), having dieted at least once (P < 0.01) and to be in dietary restraint (P < 0.05). Furthermore, the contribution of protein to energy intake was significantly higher in underreporters than in non underreporters, independently of weight status. CONCLUSIONS: These data underline that underreporting may bias the assessment of energy and macronutrient intake, particularly in studies on obesity and dietary restraint. Questions about weight concern, dieting and dietary restraint may be useful to identify subjects who underestimate their food intake.  相似文献   
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At northern Italian Counter-Reformation pilgrimage sites known as sacri monti (sacred mountains), the traditional focus on a site made sacred by events of religious importance is replaced by a condition of exile to a remote and difficult landscape. Judith Wolin argues that sacri monti as a group can be understood as mnemotopias, "memory places," whose primary function "is to allow the revisitation of 'remembered' events." An unusual site with similar intentions, designed in the 1590s by Vincenzo Scamozzi as part of a villa project, shares some defining qualities of sacri monti . Yet Scamozzi's project is unique; the goal of this paper is to show how Scamozzi participates in the mnemotopic tradition without employing explicit representational narrative. In its place stand number correspondence, a narrative use of the orders, and a layered speculation on bodies and fragments.  相似文献   
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Borys  A. 《Electronics letters》1978,14(25):817-818
It is shown that the Volterra-Wiener series approach is an attractive tool for the analysis of the distortion-induced d.c. offset. A differential input stage of an operational amplifier is taken into account as an example.  相似文献   
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In this paper, we report single step synthesis of hydrophilic superparamagnetic magnetite nanoparticles by thermolysis of Fe(acac)3 and their characterization of the properties relevant to biomedical applications like hyperthermia and magnetic resonance imaging (MRI). Size and morphology of the particles were determined by Transmission electron microscopy (TEM) while phase purity and structure of the particles were identified by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Magnetic properties were evaluated using vibrating sample magnetometer (VSM) and superconducting quantum interference device (SQUID) measurements. The as prepared nanoparticles were found to be superparamagnetic with the blocking temperature of 136 K and were easily suspendable in water. Cytotoxicity studies on human cervical (SiHa), mouse melanoma (B16F10) and mouse primary fibroblast cells demonstrated that up to a dose of 0.1 mg/ml, the magnetite nanoparticles were nontoxic to the cells. To evaluate the feasibility of their uses in hyperthermia and MRI applications, specific absorption rate (SAR) and spin-spin relaxation time (T2) were measured respectively. SAR has been calculated to be above 80 Watt/g for samples with the iron concentration of 5-20 mg/ml at 10 kA/m AC magnetic field and 425 kHz frequency. r2 relaxivity value was measured as 358.4 mM(-1)S(-1) which is almost double as compared to that of the Resovist, a commercially available MRI contrast agent. Thus the as-prepared magnetite nanoparticles may be used for hyperthermia and MRI applications due to their promising SAR and r2 values.  相似文献   
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A model of an operational amplifier suitable for small-signal non-linear analysis is developed in the present paper. The model, based on the Volterra-Wiener functional series expansion, contains the slew-rate non-linearity. By performing an accuracy analysis, the limits of its validity are also given. The stability of the single-amplifier basic structure considered as a non-linear network is studied. On the basis of the results obtained, the field on an amplitude-frequency plane for a small-signal non-linear case (FAF) is introduced for single-amplifier active filters containing operational amplifiers. It is shown that this FAF is simply related to the threshold of the input-signal amplitude at which slew-induced distortion (SID) begins.  相似文献   
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The fertilization of freshwater fish occurs in an environment that may negatively affect the gametes; therefore, the specific mechanisms triggering the encounters of gametes would be highly expedient. The egg and ovarian fluid are likely the major sources of these triggers, which we confirmed here for rainbow trout (Oncorhynchus mykiss). The ovarian fluid affected significantly spermatozoa performance: it supported high velocity for a longer period and changed the motility pattern from tumbling in water to straightforward moving in the ovarian fluid. Rainbow trout ovarian fluid induced a trapping chemotaxis-like effect on activated male gametes, and this effect depended on the properties of the activating medium. The interaction of the spermatozoa with the attracting agents was accompanied by the “turn-and-run” behavior involving asymmetric flagellar beating and Ca2+ concentration bursts in the bent flagellum segment, which are characteristic of the chemotactic response. Ovarian fluid created the optimal environment for rainbow trout spermatozoa performance, and the individual peculiarities of the egg (ovarian fluid)–sperm interaction reflect the specific features of the spawning process in this species.  相似文献   
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