scholarly journals GEODYNAMICS

GEODYNAMICS ◽  
2021 ◽  
Vol 2(31)2021 (2(31)) ◽  
pp. 84-91
Author(s):  
Yuriy Andrushchenko ◽  
◽  
Oleksandr Liashchuk ◽  
Keyword(s):  
Monitoring System ◽  
Power Plants ◽  
High Efficiency ◽  
Action Plan ◽  
Seismic Hazard Assessment ◽  
Practical Significance ◽  
Correct Identification ◽  
Monitoring Networks ◽  
Tectonic Structures ◽  
Seismic Stations

The aim of the work is to determine the possibility of using local seismological networks of nuclear power plants as elements of the seismological monitoring system of the territory of Ukraine. Estimation of local seismicity and specification of quantitative parameters of seismological influences is carried out on the basis of materials of seismological observations. Operational processing and analysis of seismic signals registered on the elements of local seismological networks of NPPs is carried out by the Main Center for Special Control of the State Space Agency of Ukraine (MCSC SSA of Ukraine). In the process of implementation of the “Seismic Hazard Assessment and Seismic Resistance Action Plan” of existing NPPs, seismic monitoring networks were deployed at Ukrainian NPPs. To date, the MCSC receives data from the local seismological networks of Rivne, Khmelnytsky and Zaporizhzhya NPPs in a continuous mode. The processing of geophysical information coming from the NPP to the FSC is carried out by the operational next shift of the center with the help of FSC hardware and software and provides reliable data on the parameters of seismic sources registered by stations, their location and energy characteristics. In total, in the period from 2017 to 2021, 36 local earthquakes were registered by NPP seismic networks in Ukraine. The epicenters of the vast majority of them are located within the Ivano-Frankivsk, Ternopil and Lviv regions. The experience of conducting instrumental observations at NPP seismic stations testifies to their high efficiency and possibility of use as full-fledged elements of the seismological monitoring system of the territory of Ukraine. According to the results of primary processing of seismic data of 2017-2021, a catalog of seismic events registered by NPP seismic stations was created. The system of interpretation of the obtained results was improved, which allowed to determine equally well local, regional and teleseismic events of different nature and energy level. The practical significance of the obtained results lies in their direct focus on solving a number of practical problems of processing and interpretation of seismological data. The use of NPP seismic stations as elements of the general system of seismological monitoring of Ukraine will increase the reliability of detection and localization of sources and the probability of correct identification of the nature of seismic phenomena, which in turn will improve the assessment of tectonic structures in Ukraine.

"Recent Patents on the Triboelectrostatic Separation of Fly Ash"

2019 ◽  
Vol 13 ◽  
Author(s):  
Haisheng Li ◽  
Wenping Wang ◽  
Yinghua Chen ◽  
Xinxi Zhang ◽  
Chaoyong Li
Keyword(s):  
Fly Ash ◽  
Power Plants ◽  
High Efficiency ◽  
Separation Efficiency ◽  
High Reliability ◽  
Operating Conditions ◽  
Security Requirements ◽  
Unburned Carbon ◽  
Efficient Operation ◽  
Triboelectrostatic Separation

Background: The fly ash produced by coal-fired power plants is an industrial waste. The environmental pollution problems caused by fly ash have been widely of public environmental concern. As a waste of recoverable resources, it can be used in the field of building materials, agricultural fertilizers, environmental materials, new materials, etc. Unburned carbon content in fly ash has an influence on the performance of resource reuse products. Therefore, it is the key to remove unburned carbon from fly ash. As a physical method, triboelectrostatic separation technology has been widely used because of obvious advantages, such as high-efficiency, simple process, high reliability, without water resources consumption and secondary pollution. Objective: The related patents of fly ash triboelectrostatic separation had been reviewed. The structural characteristics and working principle of these patents are analyzed in detail. The results can provide some meaningful references for the improvement of separation efficiency and optimal design. Methods: Based on the comparative analysis for the latest patents related to fly ash triboelectrostatic separation, the future development is presented. Results: The patents focused on the charging efficiency and separation efficiency. Studies show that remarkable improvements have been achieved for the fly ash triboelectrostatic separation. Some patents have been used in industrial production. Conclusion: According to the current technology status, the researches related to process optimization and anti-interference ability will be beneficial to overcome the influence of operating conditions and complex environment, and meet system security requirements. The intelligent control can not only ensure the process continuity and stability, but also realize the efficient operation and management automatically. Meanwhile, the researchers should pay more attention to the resource utilization of fly ash processed by triboelectrostatic separation.

scholarly journals Earthquake location in tectonic structures of the Alpine Chain: the case of the Constance Lake (Central Europe) seismic sequence

2021 ◽  
Author(s):  
Francesca D’Ajello Caracciolo ◽  
Rodolfo Console
Keyword(s):  
Central Europe ◽  
Velocity Model ◽  
Moho Depth ◽  
Seismic Sequence ◽  
Tectonic Structures ◽  
Study Region ◽  
Waveform Data ◽  
Seismic Stations ◽  
Velocity Models ◽  
Master Event

AbstractA set of four magnitude Ml ≥ 3.0 earthquakes including the magnitude Ml = 3.7 mainshock of the seismic sequence hitting the Lake Constance, Southern Germany, area in July–August 2019 was studied by means of bulletin and waveform data collected from 86 seismic stations of the Central Europe-Alpine region. The first single-event locations obtained using a uniform 1-D velocity model, and both fixed and free depths, showed residuals of the order of up ± 2.0 s, systematically affecting stations located in different areas of the study region. Namely, German stations to the northeast of the epicenters and French stations to the west exhibit negative residuals, while Italian stations located to the southeast are characterized by similarly large positive residuals. As a consequence, the epicentral coordinates were affected by a significant bias of the order of 4–5 km to the NNE. The locations were repeated applying a method that uses different velocity models for three groups of stations situated in different geological environments, obtaining more accurate locations. Moreover, the application of two methods of relative locations and joint hypocentral determination, without improving the absolute location of the master event, has shown that the sources of the four considered events are separated by distances of the order of one km both in horizontal coordinates and in depths. A particular attention has been paid to the geographical positions of the seismic stations used in the locations and their relationship with the known crustal features, such as the Moho depth and velocity anomalies in the studied region. Significant correlations between the observed travel time residuals and the crustal structure were obtained.

Study on Grinding Technology of Electrical Discharge Grinding of Curve Edge Polycrystalline Diamond

2006 ◽  
Vol 304-305 ◽  
pp. 206-209 ◽  
Author(s):  
Gang Liu ◽  
Ming Chen ◽  
Z.G. Hu ◽  
X.F. Zhu ◽  
H. Xu ◽  
...  
Keyword(s):  
Surface Quality ◽  
Electrical Discharge ◽  
High Efficiency ◽  
Practical Significance ◽  
Cnc System ◽  
Milling Cutter ◽  
Curve Edge ◽  
Grinding Machine ◽  
Five Axis ◽  
Pcd Tools

PCD tools, especially curve edge PCD compound tools are used widely in machining nonferrous and non-metal materials with high efficiency and precision because of their excellent cutting properties. But high quality grinding of PCD tools is the uppermost obstacle in application because there are great difficulties to profile and sharpen edge in grinding, especially for milling cutter and drill with curve edge. This paper studied technology of wire EDG curve edge PCD compound tools by wire electrical discharge grinding machine with five-axis CNC system. The grinding quality was evaluated by scanning electron microscope (SEM) and roughometer. Three steps processing technique (roughing, finishing and fine finishing) and optimal process parameters of wire EDG PCD tools were recommended after considering synthetically the surface quality, precision and machining efficiency. The results met the requirement of high surface quality, precision and efficiency. This paper also applied successfully the optimal technology to grind a PCD milling cutter with outer and inner blade by electrical discharge grinding machine with five-axis CNC system. By the optimal parameters, the process yielded high precision of ±4.3µm and low roughness of 0.30µm. Experiment results have great practical significance to the high precise and efficient wire EDG of PCD tools.

The method for calculating the probability of brittle destruction of NPP equipment in different operating modes with postulated defectiveness

2021 ◽  
Vol 14 (1) ◽  
pp. 34-39
Author(s):  
D. A. Kuzmin ◽  
A. Yu. Kuz’michevskiy
Keyword(s):  
Fracture Toughness ◽  
Pressure Vessel ◽  
Nuclear Power ◽  
Power Plants ◽  
Reactor Pressure Vessel ◽  
Practical Significance ◽  
Reactor Unit ◽  
Operating Modes ◽  
Brittle Destruction ◽  
Reactor Pressure

The destruction of equipment metal by a brittle fracture mechanism is a probabilistic event at nuclear power plants (NPP). The calculation for resistance to brittle destruction is performed for NPP equipment exposed to neutron irradiation; for example, for a reactor plant such as a water-water energetic reactor (WWER), this is a reactor pressure vessel. The destruction of the reactor pressure vessel leads to a beyond design-basis accident, therefore, the determination of the probability of brittle destruction is an important task. The research method is probabilistic analysis of brittle destruction, which takes into account statistical data on residual defectiveness of equipment, experimental results of equipment fracture toughness and load for the main operating modes of NPP equipment. Residual defectiveness (a set of remaining defects in the equipment material that were not detected by non-destructive testing methods after manufacturing (operation), control and repair of the detected defects) is the most important characteristic of the equipment material that affects its strength and service life. A missed defect of a considerable size admitted into operation can reduce the bearing capacity and reduce the time of safe operation from the nominal design value down to zero; therefore, any forecast of the structure reliability without taking into account residual defectiveness will be incorrect. The application of the developed method is demonstrated on the example of an NPP reactor pressure vessel with a WWER-1000 reactor unit when using the maximum allowable operating loads, in the absence of load dispersion in different operating modes, and taking into account the actual values of the distributions of fracture toughness and residual defectiveness. The practical significance of the developed method lies in the possibility of obtaining values of the actual probability of destruction of NPP equipment in order to determine the reliability of equipment operation, as well as possible reliability margins for their subsequent optimization.

OPINIE PREZESA PAA, O KTÓRYCH MOWA W ART. 36A I 39B USTAWY – PRAWO ATOMOWE JAKO PRZYKŁAD PRE-LICENCJONOWANIA OBIEKTÓW JĄDROWYCH

2021 ◽  
pp. 389-411
Author(s):  
Tomasz R. Nowacki
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Energy ◽  
Nuclear Power Plants ◽  
General Concept ◽  
Practical Significance ◽  
Investment Risk ◽  
Binding Force ◽  
Technical Factors ◽  
Energy Law

This article discusses one of the solutions adopted in the nuclear energy law, which contributes to the reduction of the investment risk. It is the so-called pre-licensing which involves the assessment of key site or technical factors at the pre-investment stage in order to avoid possible problems at the stage of investment implementation. The author analyses the Polish solutions in the context of the general concept of pre-licensing, with particular respect to: the nature of pre-licensing legal instruments (opinions), the scope and requirements of the application for an opinion, and the binding force of pre-licensing acts. The practical significance of this issue is all the greater considering governmental plans to implement nuclear power in Poland and in the light of recent activities of private entities as to the construction of smaller nuclear power plants. In the latter case, prelicensing instruments are already being exercised in practice.

FEATURES OF THE METHODOLOGY OF THERMODYNAMIC MODELING OF GAS TURBINE AND COMBINED ON THEIR BASIS POWER PLANTS

2017 ◽  
Author(s):  
Gennadii Liubchik ◽  
◽  
Nataliia Fialko ◽  
Aboubakr Regragui ◽  
Julii Sherenkovskii ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Thermodynamic Analysis ◽  
Thermodynamic Modeling ◽  
Power Plants ◽  
High Efficiency ◽  
Technical Facility

The article presents the enthalpy-entropy methodology of thermodynamic analysis of gas turbine and combined power plants on their basis, the results of testing the method on a real technical facility, proving its high efficiency.

scholarly journals A Multi-Technology Analysis of the 2017 North Korean Nuclear Test

2018 ◽  
Author(s):  
Peter Gaebler ◽  
Lars Ceranna ◽  
Nima Nooshiri ◽  
Andreas Barth ◽  
Simone Cesca ◽  
...  
Keyword(s):  
Monitoring System ◽  
Body Wave ◽  
Test Site ◽  
Nuclear Test ◽  
International Monitoring System ◽  
Seismic Stations ◽  
Technology Analysis ◽  
Tnt Equivalent ◽  
International Monitoring ◽  
Strong Surface

Abstract. On September 3rd 2017 official channels of the Democratic People's Republic of Korea announced the successful test of a thermonuclear device. Only seconds to minutes after the alleged nuclear explosion at the Punggye-ri nuclear test site in the mountainous region in the country's northeast at 03:30:02 (UTC) hundreds of seismic stations distributed all around the globe picked up strong and distinct signals associated with an explosion. Different seismological agencies reported body wave magnitudes of well above 6.0, consequently estimating the explosive yield of the device in the order of hundreds of kilotons TNT equivalent. The 2017 event can therefore be assessed being multiple times larger in energy than the two preceding events in January and September 2016. This study provides a multi-technology analysis of the 2017 North Korean event and its aftermath using a wide array of geophysical methods. Seismological investigations locate the event within the test site at a depth of approximately 0.8 km below surface. The radiation and generation of P- and S-wave energy in the source region is significantly influenced by the topography of the Mt. Mantap massif. Inversions for the full moment tensor of the main event reveal a dominant isotropic component accompanied by significant amounts of double couple and compensated linear vector dipole terms, confirming the explosive character of the event. Analysis of the source mechanism of an aftershock that occurred around eight minutes after the test in the direct vicinity suggest a cavity collapse. Measurements at seismic stations of the International Monitoring System result in a body wave magnitude of 6.2, which translates to an yield estimate of around 400 kilotons TNT equivalent. The explosive yield is possibly overestimated, since topography and depth phases both tend to ehance the peak amplitudes of teleseismic P-waves. Interferometric Synthetic-Aperture-Radar analysis using data from the ALOS-2 satellite reveal strong surface deformations in the epicenter region. Additional multispectral optical data from the Pleiades satellite show clear landslide activity at the test site. The strong surface deformations generated large acoustic pressure peaks, which were observed as infrasound signals with distinctive waveforms even in distances of 400 km. In the aftermath of the 2017 event atmospheric traces of the fission product 133Xe have been detected at various locations in the wider region. While for 133Xe measurements in September 2017 the Punggye-ri test site is disfavored as source by means of atmospheric transport modeling, detections in October 2017 at the International Monitoring System station RN58 in Russia indicate a potential delayed leakage of 133Xe at the test site from the 2017 North Korean nuclear test.

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