electric capacity
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2021 ◽  
Vol 21 (6) ◽  
pp. 227-237
Author(s):  
Seok-Ju Kim ◽  
Do-Kyun Kim

In soil dams and embankments made of soil, deterioration and stress release owing to internal and external influences occur, and the instability of the body increases as the shear strength decreases. In particular, understanding the location and flow of underground water is very important for securing the long-term stability of waterfront structures in contact with water. However, the physical limitations of measuring equipment cause many difficulties in understanding the existence and location of groundwater over a long period of time. In this study, measuring equipment using electric capacity was developed for the long-term measurement of groundwater, and contactless measuring sensors were manufactured to eliminate the possibility of corrosion by water. In addition, the precision of the measurement data was improved by applying waterproof and water-repellent coatings to the measurement sensor. Laboratory tests conducted using the developed equipment demonstrate the high precision of the measurement data according to the groundwater level change and enhanced durability of the sensor, which facilitate long-term measurements in the field.


Author(s):  
Kouji Maeda ◽  
Shinji Yae ◽  
Naoki Fukumuro ◽  
Kenji Iimura ◽  
Ayumu Matsumoto

Abstract A nickel-metal hydride (Ni–MH) prototype battery completely immersed in an aqueous electrolyte solution of KOH under high pressure was fabricated to examine the effects of high pressure on the quality of Ni–MH batteries. The small battery cell comprised positive and negative electrode materials, as used in electric vehicles, and an Ag/AgO reference electrode. The electric capacity of the Ni–MH battery was measured at different temperatures and pressures with small currents and charge/discharge voltages of 1.6 – 1.0 V. High pressures were found to clearly and effectively enhance the electric capacity of the Ni–MH battery at larger currents. The considerable effect of high pressure on the Ni–MH battery was elucidated by the change in internal resistance during the charge/discharge cycle life experiment, indicating that the voltage of the positive electrode did not appreciably change at a high pressure compared to that of the negative electrode. Moreover, the use of large currents in rapid charge/discharge cycle tests at high pressures of up to 30 MPa resulted in charge/discharge cycles that were five times faster and a quick recovery of capacity was achieved in the 0.5 – 2.1 V range.


Globus ◽  
2021 ◽  
Vol 7 (6(63)) ◽  
pp. 10-16
Author(s):  
Galina Nikolaevna Sidorenko ◽  
Boris Innokentievich Laptev ◽  
Nikolai Petrovich Gorlenko

The paper evaluates changes in the structure of water and aqueous solutions of sodium chloride in the wall layer on the basis of dielectrometry and correlation analysis. It is shown that when the distance to the solid surface decreases, there is a multi-fold nonlinear decrease in the electrical capacitance and a nonlinear change in the Sr parameter, which characterizes the magnitude of the change in the electrical capacitance of the conduction fluid when the distance to the solid surface changes. The parameters used in the work (electric capacity of liquids and Sr ) can be used to evaluate the changes in the structural organization of aqueous solutions in the wall (boundary) layer and to interpret the processes occurring in the liquid layer at the interface of the solid – aqueous solution phases.


2021 ◽  
Vol 23 (9) ◽  
pp. 2741-2755
Author(s):  
Marvin Scherzinger ◽  
Marvin Kaltschmitt

AbstractThis study examines whether vapothermal pre-treatment is technically feasible and brings economic advantages for a subsequent anaerobic co-fermentation of reeds together with sewage sludge. This is illustrated by the example of remote sites located close to constructed wetlands in the Persian Gulf states. Thus, eight different biogas plant configurations with an installed electric power between 75 and 450 kW, each with and without vapothermal pre-treatment, are investigated in detail related to technical and economic figures. Within the technical assessment, suitable plant components are chosen and overall plant layouts are designed and dimensioned. Furthermore, the requirements on the substrate by means of quantity, pre-treatment and storage capacities are investigated. Based on this, an economic evaluation following the annuity method is performed in order to calculate the respective electricity production costs. The results show that the thermal energy required for vapothermal pre-treatment can be obtained completely from the residual heat of the combined heat and power unit used in each case. Additionally, the specific electricity production costs can be reduced by a vapothermal pre-treatment up to 7 % related to the systems without pre-treatment. Furthermore, a comparison shows that vapothermal pre-treatment can compete with other pre-treatment methods such as steam explosion and hydrothermal pre-treatment for plants with higher installed electric capacity. In addition, it is shown that the considered cases can compete with the production of electricity using diesel as a fuel at a fuel equivalent price of 1.00 € Graphic abstract


Globus ◽  
2021 ◽  
Vol 7 (3(60)) ◽  
pp. 12-20
Author(s):  
G.V. Tarassenko ◽  
M.G. Tarassenko

Cold fusion is not possible in atmospheric conditions but it is possible underground. Synthesis formation is connected with electricity in the entrails of the earth. Electricity is produced with the help of friction and geospheres speed differential from the core (20-40 m/s to the surface), the speed of which according to GPS data is 2-16 cm per year. Faraday has determined planet electric capacity with 1 farad. Continent drift takes place at the expense of geospheres rotation, leading to subduction of ocean and continental plates, abduction, spreading, rifting and collision. An example of planet formation is ball concretions.


2021 ◽  
Author(s):  
Caihua Zhou ◽  
Chao Wang ◽  
Guang Fan

Abstract Three kinds of composites were built by nitrogen-doped grapheme and phosphomolybdic acid. Based on the density functional theory, the combined energies, charge populations, orbital distributions and densities of states (DOS) were calculated. The results show that the short rage interaction can be formed between oxygen atom and nitrogen atom, and the charge can be transferred from phosphomolybdic acid to graphene. It is found that the conductive bands (CB) of phosphomolybdic acid move to lower level energy and there are more valence bands (VB) in composites from DOS. It is revealed that composites have the higher electric capacity due to nitrogen-doped graphene can receive more electrons from phosphomolybdic acid.


Author(s):  
M. O Kostin ◽  
A. M Mukha ◽  
O. H Sheikina ◽  
O. Y Kurylenko

Purpose. Development of a method for determining the main functional parameters of on-board supercapacitor recuperative energy storage based on the asymptotic theory of extreme statistics by Gumbel, taking into account stochastic nature of changes in recuperated voltage and current. Methodology. To achieve this purpose, methods, devices and computer systems for temporary registration of recuperated voltages and currents on operating electric locomotives, methods of the theory of random processes and methods of probabilistic and statistical processing of registrograms of voltages and currents were used. Findings. A computational and experimental method for estimating recuperative energy has been proposed and practically applied. A probabilistic method has been developed for determining the energy and electric capacity of on-board supercapacitor recuperative energy storage units. Numerical probabilistic and statistical calculations of the energy and electric capacity of on-board storage for the VL8 and VL11M6 electric locomotives during their operation in the sections of Prydniprovska railway have been carried out. It was found that the energy and electric capacity of on-board storage devices are distributed according to an exponential law with a clear prevalence of their minimum values and in compliance with direct proportionality between them. Originality. For the first time, an autonomous phase of recuperative braking mode of an electric rolling stock has been developed, which makes it possible to significantly reduce the mass and dimension of a supercapacitor storage. The asymptotic theory of extreme statistics by Gumbel was adapted to the method for calculating energy and electric capacity of an on-board storage device, which made it possible to take into account the influence of stochastic nature of changes in the recuperated voltage and current. The probabilistic influence regularities of the change nature in the recuperation energy on the capacity of on-board storage in the phase of recuperative braking have been established. Further development was obtained by a computational-experimental method for assessing the recuperative energy, based on monitoring and using the time dependences of voltage and current obtained in real modes of recuperative braking. For the first time in electric traction systems, it was proposed to carry out the transition from the recuperative braking mode to the recuperative regeneration mode. Practical value. The developed method and technique based on it make it possible to evaluate functional parameters of on-board storage device of all types of electric rolling stock, considering stochastic nature of recuperated voltages and currents. Numerical-graphic dependences of the energy intensity and capacity of the on-board storage are recommended for predicting and evaluating these parameters for various modes of recuperative braking. Since the task of designing an on-board storage unit (in terms of mass and dimensions) is ambiguous, therefore, in each specific case of the type of electric locomotive and recuperation modes, it must be solved individually, taking into account the probability of the corresponding capacitance values.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zarrar Khan ◽  
Gokul Iyer ◽  
Pralit Patel ◽  
Son Kim ◽  
Mohamad Hejazi ◽  
...  

AbstractLong-term temperature change and variability are expected to have significant impacts on future electric capacity and investments. This study improves upon past studies by accounting for hourly and monthly dynamics of electricity use, long-term socioeconomic drivers, and interactions of the electric sector with rest of the economy for a comprehensive analysis of temperature change impacts on cooling and heating services and their corresponding impact on electric capacity and investments. Using the United States as an example, here we show that under a scenario consistent with a socioeconomic pathway 2 (SSP2) and representative concentration pathway 8.5 (RCP 8.5), mean temperature changes drive increases in annual electricity demands by 0.5-8% across states in 2100. But more importantly, peak temperature changes drive increases in capital investments by 3-22%. Moreover, temperature-induced capital investments are highly sensitive to both long-term socioeconomic assumptions and spatial heterogeneity of fuel prices and capital stock characteristics, which underscores the importance of a comprehensive approach to inform long-term electric sector planning.


2020 ◽  
Vol 4 (52) ◽  
pp. 8-16
Author(s):  
A. Rak ◽  
◽  
V. Busher ◽  
O. Glazeva ◽  
◽  
...  

Purpose. The paper compares the traditional method of calculating the parameters of electric motion of ships in auxiliary emergency modes at low speeds of the vessel with another, simplified because it does not require the use of a large number of diagrams to determine the resistance of the vessel. But according to a simplified method for this example – a container ship with a capacity of 16,000 containers with the main engine capacity of 61776 kW, a synchronous machine with a capacity of up to 6 MW in engine mode, and three diesel generators with an electric capacity of 3187 kW – 39 % more power is obtained. Own experience of operation of the vessel in modes with electric movement – loading of diesel generators in this mode on the vessel about 70 % that is received by calculations. Thus, when upgrading the propulsion system or designing new vessels, it is advisable to compare the results of two calculations of the power of diesel generators at the limit of the minimum stable speed of the main engine and choose the larger of the results. Methodology. Comparison of specific and absolute fuel consumption, made on the basis of known approximation polynomials for low- and high-speed types of diesel of the company at auxiliary emergency movement shows that at the movement from high-speed diesel generators MAK8M32S fuel consumption decreases by 24 %, then at the maintenance of the main engine 12 RTflex-96C from WÄRTSILÄ-SULZER. Results. Therefore, the use of electric motion allows you to save engine power of the main engine, reduce fuel consumption. This ratio is observed on most maritime transport vessels. And given that diesel generators operate at almost optimal load, and the main engine – at idle, electric motion provides a significant reduction in harmful emissions into the atmosphere. The latter is also true for a ship where the synchronous engine is located behind the main engine, although fuel consumption, in this case, increases by 32 %. Figures 9, tables 6, references 15.


2020 ◽  
Vol 25 (6) ◽  
pp. 563-568
Author(s):  
V.V. Urumov ◽  
◽  

The electroluminescent light source can be used as flexible compact flat sources of uniform illuminating. The studies on improvement of its main characteristics, especially of color intensity generation, continue. In the paper the possibility of using the changing capacitive and current characteristics of flexible light sources - electroluminescent panels to fix and determine the level of external radiation, which includes the near infrared, optical and ultraviolet ranges, has been shown. The degree of the influence of radiation on the capacitive and current characteristics of these structures based on ZnS: Cu, Mn phosphor using a barium titanate ferroelectric has been revealed. During the studies the instrumental and expert analysis as well as the non-destructive and destructive technological control have been used. It has been found that while changing the radiation intensity from 0 to 2500 kd/m the electric capacity of the structure with 600 cm area becomes 25 % increased, and the intensity increase leads to considerable proportional increase (up to 20 %) of the structure conductivity current


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