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Analysis of floor-to-column pounding of buildings founded on different soil types
- Mahmoud Miari
- Robert Jankowski
2022 Pełny tekst Bulletin of Earthquake Engineering
The aim of this study is to investigate the effect of the soil type on buildings experiencing floor-to-column pounding during earthquakes. Five buildings with 4-storeys, 6-storeys, and 7-storeys were considered. Three types of the 4-storey building with different total heights were taken into account which leads to floor-to-column pounding at 1/3, 1/2 and 2/3 of the height of the impacted column. Two pounding scenarios were considered, i.e. pounding between the 4-storey and 6-storey buildings (three cases when collisions occur at 1/3, 1/2 and 2/3 of the height of the impacted column) and pounding between the 4-storey and 7-storey buildings (three cases when collisions occur at 1/3, 1/2 and 2/3 of the height of the impacted column). In the first part of this study, the shear demands of the columns at the contact area were studied and compared with the no pounding case to investigate the effect of the floor-to-column pounding. Then, the shear demands of the columns at the contact area were studied for buildings founded on different soil types to investigate the effect of the soil type on the structural response. The results of this study illustrate that the shear demands of the impacted column significantly increase due to collisions and it exceeds the shear strength in all cases. Moreover, impacted column experiences higher shear demands for buildings founded on the soft clay soil, then for buildings founded on the stiff soil, then for buildings founded on very dense soil and soft rock, and finally for buildings founded on the rock and hard rock.
Analysis of human behavioral patterns
- Agata Kołakowska
2022
Widespread usage of Internet and mobile devices entailed growing requirements concerning security which in turn brought about development of biometric methods. However, a specially designed biometric system may infer more about users than just verifying their identity. Proper analysis of users’ characteristics may also tell much about their skills, preferences, feelings. This chapter presents biometric methods applied in several areas, such as user authentication, emotion recognition, diagnosis and therapy of disorders. The presented algorithms mainly focus on behavioral biometrics based on data from standard input devices.
Analysis of Impulse Responses Measured in Motion in a Towing Tank
- Agnieszka Czapiewska
- Andrzej Łuksza
- Ryszard Studański
- Andrzej Żak
2022 Pełny tekst Electronics
The growing interest in developing autonomous underwater vehicles (AUVs) and creating underwater sensor networks (USNs) has led to a need for communication tools in underwater environments. For obvious reasons, wireless means of communication are the most desirable. However, conducting research in real conditions is troublesome and costly. Moreover, as hydroacoustic propagation conditions change very significantly, even during the day, the assessment of proposed underwater wireless communication methods is very difficult. Therefore, in the literature, there are considered simulators based on real measurements of underwater acoustic (UWA) channels. However, these simulators make an assumption that, during the transmission of elementary signals, the impulse response does not change. In this article, the authors present the results of the measurements realized in a towing tank where the transmitter could move with a precisely set velocity and show that the analyzed channel was non-stationary, even during the time of the transmission of a single chirp signal. The article presents an evaluation method of channel stationarity at the time of the chirp transmission, which should be treated as novelty. There is also an analysis of the impulse responses measured in motion in a towing tank.
Analysis of Methods for Determining Shallow Waterbody Depths Based on Images Taken by Unmanned Aerial Vehicles
- Mariusz Specht
- Marta Wiśniewska
- Andrzej Stateczny
- Cezary Specht
- Bartosz Szostak
- Oktawia Lewicka
- Marcin Stateczny
- Szymon Widźgowski
- Armin Halicki
2022 Pełny tekst SENSORS
Hydrographic surveys enable the acquisition and processing of bathymetric data, which after being plotted onto nautical charts, can help to ensure safety of navigation, monitor changes in the coastal zone, and assess hydro-engineering structure conditions. This study involves the measurement of waterbody depth, identification of the seabed shape and geomorphology, the coastline course, and the location of underwater obstacles. Hydroacoustic systems mounted on vessels are commonly used in bathymetric measurements. However, there is also an increasing use of Unmanned Aerial Vehicles (UAV) that can employ sensors such as LiDAR (Light Detection And Ranging) or cameras previously not applied in hydrography. Current systems based on photogrammetric and remote sensing methods enable the determination of shallow waterbody depth with no human intervention and, thus, significantly reduce the duration of measurements, especially when surveying large waterbodies. The aim of this publication is to present and compare methods for determining shallow waterbody depths based on an analysis of images taken by UAVs. The perspective demonstrates that photogrammetric techniques based on the SfM (Structure-from-Motion) and MVS (Multi-View Stereo) method allow high accuracies of depth measurements to be obtained. Errors due to the phenomenon of water-wave refraction remain the main limitation of these techniques. It was also proven that image processing based on the SfM-MVS method can be effectively combined with other measurement methods that enable the experimental determination of the parameters of signal propagation in water. The publication also points out that the Lyzenga, Satellite-Derived Bathymetry (SDB), and Stumpf methods allow satisfactory depth measurement results to be obtained. However, they require further testing, as do methods using the optical wave propagation properties.
Analysis of Organic Rankine Cycle efficiency and vapor generator heat transfer surface in function of the reduced pressure
- Dariusz Mikielewicz
- Jarosław Mikielewicz
2022 Pełny tekst ENERGY
In the paper presented is analysis of the influence of reduced pressure on efficiency and heat transfer area of vapor generator of Organic Rankine Cycle (ORC) in case of subcritical and supercritical parameters of operation. Compared are two cases of subcritical and supercritical ORC featuring a similar arrangement of heat source supply and heat removal, that is featuring the same temperatures of working fluid before the turbine, and the same condensation temperature in the respective cycles. The analysis is helpful in selection of the appropriate pressure in the vapor generator. In accomplished analyses a selection of wet ORC working fluids are scrutinized for a given range of heat source temperatures with respect to influence on efficiency of thermodynamic cycle and vapor generator area of heat transfer on installation and operation costs to illustrate the issue. Investment cost of a vapor generator in the ORC cycle accounts for a main share of expenditure alongside the cost of the expanding machine. Results of calculations show that from the point of view of cycle efficiency and size of vapor generator the pressures close to critical fluid pressure are usually optimal. Some working fluids feature even an optimal pressure. For the region close to critical point authors elaborated own method for heat transfer coefficients elaboration, which is useful in more exact estimations of heat transfer process in vapor generator. In case of a heat source with a relatively high temperature, it is better to consider a thermodynamic cycle with supercritical parameters even if as a result the vapor generator is slightly larger than for the case of a subcritical cycle. There will always be a more pronounced gain in efficiency compared to the expense induced by the heat transfer surface area of vapor generator.
Analysis of pounding between adjacent buildings founded on different soil types
- Mahmoud Miari
- Robert Jankowski
2022 SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
Earthquake-induced pounding was experienced in many previous earthquakes and it was found to be a critical issue. This study investigates the effect of pounding between buildings founded on the same and different soil types. Three 3-D buildings with 4, 6 and 8 storeys were considered in this study. Three pounding scenarios were taken into account, i.e. pounding between 4-storey and 6-storey buildings, between 4-storey and 8-storey buildings and between 6-storey and 8-storey buildings. To consider the soil type, the effects of different site parameters on the response of buildings exposed to earthquakes was firstly investigated so that the values that lead to significant effects and larger responses could be taken into account in further study related to structural interactions. In the next stage of the investigation, the effects of pounding between buildings founded on a specified soil type were analysed and compared with the no pounding case. The results of this part of this study show that pounding significantly increases the peak accelerations in all situations. Indeed, the peak displacements experience both amplification and de-amplification. Moreover, the shear forces were found to be increased for all storeys in all the cases with few exceptions concerning the top storeys. Finally, pounding between 4-storey and 8-storey buildings as well as between 6-storey and 8-storey buildings was considered under different soil types defined in the ASCE 7-10 code (hard rock, rock, very dense soil and soft rock, stiff soil and soft clay soil). The results of this stage of this study show that the highest displacements and shear forces can be expected for buildings founded on the soft clay soil, then for buildings founded on the stiff soil, then for buildings founded on very dense soil and soft rock, and finally for buildings founded on the rock and hard rock.
Analysis of the Factors Affecting Static In Vitro Pepsinolysis of Food Proteins
- Natsumi Maeda
- Dorota Dulko
- Adam Macierzanka
- Christian Jungnickel
2022 Pełny tekst MOLECULES
In this meta-analysis, we collected 58 publications spanning the last seven decades that reported static in vitro protein gastric digestion results. A number of descriptors of the pepsinolysis process were extracted, including protein type; pepsin activity and concentration; protein concentration; pH; additives; protein form (e.g., ‘native’, ‘emulsion’, ‘gel’, etc.); molecular weight of the protein; treatment; temperature; and half-times (HT) of protein digestion. After careful analysis and the application of statistical techniques and regression models, several general conclusions could be extracted from the data. The protein form to digest the fastest was ‘emulsion’. The rate of pepsinolysis in the emulsion was largely independent of the protein type, whereas the gastric digestion of the native protein in the solution was strongly dependent on the protein type. The pepsinolysis was shown to be strongly dependent on the structural components of the proteins digested—specifically, -sheet-inhibited and amino acid, leucine, methionine, and proline-promoted digestion. Interestingly, we found that additives included in the digestion mix to alter protein hydrolysis had, in general, a negligible effect in comparison to the clear importance of the protein form or additional treatment. Overall, the findings allowed for the targeted creation of foods for fast or slow protein digestion, depending on the nutritional needs.
Analysis of the Hydrodynamic Properties of the 3-Column Spar Platform for Offshore Wind Turbines
- Ewelina Ciba
- Paweł Dymarski
- Mirosław Grygorowicz
2022 Pełny tekst Polish Maritime Research
The article presents a design of a floating platform for offshore wind turbines. The concept is a modification of the Spar design and consists of three variable section columns connected to each other by a ballast tank in the lower part of the platform. This solution makes it possible to influence the position of the centre of buoyancy and the centre of mass of the structure. Compared to the classic Spar platform structure, the centre of buoyancy can be higher than mid-draft, which will provide the platform with greater stability. At the same time, this concept is better, in terms of technology, because of its modular structure and smaller bending radii.On the basis of the model testing performed, the hydrodynamic coefficients of the designed platform and its response to a given regular wave were determined (the transfer functions for heave and pitch motion were determined). Then, based on the damping coefficients, the platform was modelled in the ANSYS AQWA program and the results were very similar.
Analysis of the influence of external conditions on temperature readings in thermograms and adaptive adjustment of the measured temperature value
- Piotr Filipowicz
- Mateusz Kowalewski
- Kinga Słomińska
- Mariusz Kaczmarek
2022
Measuring human temperature is a crucial step in preventing the spread of diseases such as COVID-19. For the proper operation of an automatic body temperature measurement system throughout the year, it is necessary to consider outdoor conditions. In this paper, the effect of atmospheric factors on facial temperature readings using infrared thermography is investigated. A thorough analysis of the variation of facial temperature with the prevailing atmospheric conditions was carried out using recordings collected over two years and compared with air temperature values at 1 hour accuracy. A method that takes account of outdoor conditions on temperature readings was proposed. We developed a correction curve with coefficients values based on an analysis of the recordings of people entering the building. Such a method will allow an effective real-time fever screening in public places.
Analysis of the influence of polystyrene microplastics and their derivatives on the DNA of human colon epithelial cells HT29 with the comet assay
- Paweł Filipkowski
- Aleksandra Ćwiklińska
- Zuzanna Koziara
- Karol Parchem
- Łukasz Zedler
- Jacek Ryl
2022 Pełny tekst Research Square
We have been using plastic for almost a century and nowadays a lot of them circulates as pollutants in the environment and still defragmenting to micro and nanoscale. The exposition through the food chain and its precise impact on human health is still not clear. In our study, we tested real food packaging after contact with food products and real thermoinsulation and environmental samples of polystyrene in different model liquids, We used a comet assay, mass spectrometry (MS) of fluids which were in contact with packaging, free styrene measurement by Wijs method according to ISO standard and FTIR of wrap, to get an overview of their possible harmful effects. In the presented study, only low genotoxic effect (5-6% DNA damage) was observed.. In addition, no adverse effects were detected in the mass spectrometry. For analysed coloured polystyrene food packaging materials, we noticed a lower level of free styrene monomers in dairy packages that originally contained products with fruits. Exposure of cells to long-term seasoned polystyrene caused less DNA fragmentation than in the case of samples in saline.. Unfortunately, to this day no one knows how much free styrene and derivatives we eat with our daily food products and from food packaging. Based on our results and knowledge, more attention is needed with regard to polystyrene contamination. In particular, a wider analysis of the impact of interactions with the microbiota and the food matrix, which is in direct contact with the polystyrene packaging, should be carried out. The results of our research show that polystyrene and its derivatives from food packaging can potentially have a negative effect on the DNA of human colon epithelial cells. We recommend seasoning of freshly formed polystyrene products and increasing personal protection in relation to workers of the polystyrene foaming factories This applies primarily to dairy products, readily consumed by children, which are rich in both organic acids and salts, and the presence of these ingredients enhances the genotoxic effects. According to our best knowledge, this is the first study using actual polystyrene food packaging available on the market.
Analysis of Transformation Methods of Hydroacoustic and Optoelectronic Data Based on the Tombolo Measurement Campaign in Sopot
- Oktawia Lewicka
- Mariusz Specht
- Andrzej Stateczny
- Cezary Specht
- Czesław Dyrcz
- Paweł Dąbrowski
- Bartosz Szostak
- Armin Halicki
- Marcin Stateczny
- Szymon Widźgowski
2022 Pełny tekst Remote Sensing
Measurements in the coastal zone are carried out using various methods, including Global Navigation Satellite Systems (GNSS), hydroacoustic and optoelectronic methods. Therefore, it is necessary to develop coordinate transformation models that will enable the conversion of data from the land and marine parts to one coordinate system. The article presents selected issues related to the integration of geodetic and hydrographic data. The aim of this publication is to present the various transformation methods and their effects that relate to the data from the tombolo measurement campaign in Sopot conducted in 2018. Data obtained using GNSS Real Time Kinematic (RTK) measurements, Terrestrial Laser Scanning (TLS), the Unmanned Aerial Vehicle (UAV) and the Unmanned Surface Vehicle (USV) were transformed. On the basis of the coordinate transformation methods used, it can be concluded that the adjustment calculus method obtained the best results for the plane coordinates, while the method of P.S. Dąbrowski et al. obtained the best results for the height coordinates. The standard deviation for the difference of the modelled coordinates acquired by the method of P.S. Dąbrowski et al. with respect to the reference coordinates amounted to: 0.022 m (Northing), 0.040 m (Easting) and 0.019 m (height), respectively, while the adjustment calculus method allowed to obtain the following values: 0.009 m (Northing), 0.005 m (Easting) and 0.359 m (height). It can be assumed that a combination of these two seven-parameter transformation methods would provide the best results. In the future, a new seven-parameter transformation method should be developed based on the synthesis of these two existing methods.
Analysis of Video Transmission Capabilities in a Simulated OFDM-Based Supplementary BPL-PLC System
- Grzegorz Debita
- Przemysław Falkowski-Gilski
- Monika Zamłyńska
- Marcin Habrych
- Bogdan Miedziński
- Teresa Kupczyk
- Bartosz Polnik
2022 Pełny tekst ENERGIES
The design and maintenance of a reliable communication system, especially in harsh working conditions for the oil and mining industry, brings many challenges. With the use of a video transmission system, one can monitor the crew and their working environment. Broadband over power line–power line communication (BPL-PLC) seems an ideal medium for such a service, since it enables the use of the existing wired infrastructure for supplementary applications. In this paper, we perform a set of simulations for a dedicated wired medium as well as analyses of a visual data transmission system, designed to deliver video content with quadrature amplitude modulation (QAM) and orthogonal frequency division multiplexing (OFDM). We investigate a set of video sequences at 480 × 270 resolution under varying network conditions, including signal-to-noise ratio (SNR) and bit error rate (BER). We perform a subjective evaluation study of video content transmitted over our simulated communication link. The results of this study may aid parties involved in designing additional services for portable devices and user terminals, including reliable means of contact, surveillance and monitoring. The obtained results may be of particular interest to researchers and professionals related to the Industry 4.0 and Internet of things (IoT) concepts.
Analysis-by-synthesis paradigm evolved into a new concept
- Bożena Kostek
2022 Journal of the Acoustical Society of America
This work aims at showing how the well-known analysis-by-synthesis paradigm has recently been evolved into a new concept. However, in contrast to the original idea stating that the created sound should not fail to pass the foolproof synthesis test, the recent development is a consequence of the need to create new data. Deep learning models are greedy algorithms requiring a vast amount of data that, in addition, should be correctly annotated. Annotation is a bottleneck to getting quality-reliable data as the process relies on annotating a person’s experience and, in many cases, personality related issues. So, the new approach is to create synthesized data based on a thorough analytical examination of a musical/speech signal resulting in cues for a deep model of how to populate data to overcome this problem. Typically, a 2D feature space is employed, e.g., mel spectrograms, cepstrograms, chromagrams, etc., or a wave-based representation with the counterpart on the algorithmic side called wavenet. In this paper, examples of 2D musical/ speech signal representation are presented, along with deep models applied. Creating new data in the ontext of applications is also shown. In conclusion, further possible directions of this paradigm development which is now beyond the conceptual phase, are presented.
Analytical chemistry in technical approaches: immobilization of biosorbent waste containing heavy metals in cemented materials
- Rahmiana Zein
- Syiffa Fauzia
- Zuzanna Bielan
- Hermansyah Aziz
- Dahyunir Dahlan
- Piotr Konieczka
- Bartłomiej Cieślik
2022 Pełny tekst MONATSHEFTE FUR CHEMIE
An ecologically safe and economically justified method of stabilization of the used biosorbents was developed. Sorbent contaminated with heavy metals has been successfully solidified/stabilized using a hydraulic binder. The test results indicated that up to 1% of the biosorbent residue used could be added without compromising the compressive strength of the mortar. The compressive strength of the modified mortars did not change significantly even after 20 freeze/thaw cycles. The analytical methods such as Flame Atomization-Atomic Absorption Spectrometer, Graphite Furnace-Atomic Absorption Spectrometer, and Cold Vapor-Atomic Absorption Spectrometry were utilized to examine the leaching behavior of selected heavy metals during harsh condition exposure. The leachability of selected heavy metals was found to be below the limit allowed by the US EPA after immersion and agitation for 10 days in artificial water solutions (seawater, groundwater, and rainwater). X-Ray Diffraction and Brunauer–Emmett–Teller data showed no significant changes in the crystalline structure and surface area of the modified mortars after treatment. Research showed that mixing the adsorbent used with mortar was effective in immobilizing heavy metals and allowed the implementation of a so-called ‘zero waste’ management method.
Analytical Estimation of Power Losses in a Dual Active Bridge Converter Controlled with a Single-Phase Shift Switching Scheme
- Marek Turzyński
- Serafin Bachman
- Marek Jasiński
- Szymon Piasecki
- Marek Ryłko
- Huang-Jen Chiu
- Shih-hao Kuo
- Yu-Chen Chang
2022 Pełny tekst ENERGIES
Micro-grid solutions around the world rely on the operation of DC/DC power conver- sion systems. The most commonly used solution for these topologies is the use of a dual active bridge (DAB) converter. Increasing the efficiency and reliability of this system contributes to the improvement in the stability of the entire microgrid. This paper discussed an analytical method of energy efficiency and power loss estimation in a single phase dual active bridge (DAB) converter controlled with a single-phase shift (SPS) modulation scheme for microgrid system stability. The presented approach uses conduction and commutation losses of semiconductors and high frequency transformer. All parameters required for the calculation may be obtained from the manufacturers’ datasheets or can be based on a simple measurement. The approach was validated by the comparison of the estimated energy efficiency characteristics with the measured ones for a prototype of a 5 kW single phase DAB converter equipped with silicon carbide metal-oxide semiconductor field-effect transistors (SiC MOSFET)
Analytical Methods for Causality Evaluation of Photonic Materials
- Tomasz Stefański
- Jacek Gulgowski
- Kosmas L. Tsakmakidis
2022 Pełny tekst Materials
We comprehensively review several general methods and analytical tools used for causality evaluation of photonic materials. Our objective is to call to mind and then formulate, on a mathematically rigorous basis, a set of theorems which can answer the question whether a considered material model is causal or not. For this purpose, a set of various distributional theorems presented in literature is collected as the distributional version of the Titchmarsh theorem, allowing for evaluation of causality in complicated electromagnetic systems. Furthermore, we correct the existing material models with the use of distribution theory in order to obtain their causal formulations. In addition to the well-known Kramers–Krönig (K–K) relations, we overview four further methods which can be used to assess causality of given dispersion relations, when calculations of integrals involved in the K–K relations are challenging or even impossible. Depending on the given problem, optimal approaches allowing us to prove either the causality or lack thereof are pointed out. These methodologies should be useful for scientists and engineers analyzing causality problems in electrodynamics and optics, particularly with regard to photonic materials, when the involved mathematical distributions have to be invoked.
Analytical Traffic Model for a Multidomain IMS/NGN Network Including Service and Transport Stratum
- Sylwester Kaczmarek
- Maciej Sac
- Michał Cieśliński
2022
This paper addresses the problem of modelling call processing performance (CPP) in a multidomain Next Generation Network (NGN) architecture including the elements of the IP Multimedia Subsystem (IMS) in service stratum and based on the Multiprotocol Label Switching (MPLS) technology in transport stratum. An analytical traffic model for such an architecture is proposed by integrating the formerly implemented submodels of service stratum and MPLS-based transport stratum. The integrated analytical model allows investigation of mean Call Set-up Delay (E(CSD)) and mean Call Disengagement Delay (E(CDD)) for a large set of input variables corresponding to both IMS/NGN strata. The evaluation of E(CSD) and E(CDD), which are a subset of CPP parameters, is very important for both network users and operators. Details regarding the structure and operation of the integrated traffic model are provided in this paper. Moreover, the results of investigations are described, which demonstrate that this model is correctly implemented, reflects the operation of a multidomain IMS/NGN network and may be used in further research.
Analyzing Wind Energy Potential Using Efficient Global Optimization: A Case Study for the City Gdańsk in Poland
- Olgun Aydin
- Bartłomiej Igliński
- Krzysztof Krukowski
- Marek Siemiński
2022 Pełny tekst ENERGIES
Wind energy (WE), which is one of the renewable energy (RE) sources for generating electricity, has been making a significant contribution to obtaining clean and green energy in recent years. Fitting an appropriate statistical distribution to the wind speed (WS) data is crucial in analyzing and estimating WE potential. Once the best suitable statistical distribution for WS data is determined, WE potential and potential yield could be estimated with high accuracy. The main objective of this paper is to propose a novel approach for calculating wind energy potential. For this purpose, the Efficient Global Optimization (EGO) technique was proposed for fitting a statistical distribution to WS data and the performance of the technique was compared with genetic algorithm (GA), simulated annealing (SA), and differential evolution (DE). Performance metrics showed that EGO is providing better estimations compared with GA, SA, and DE. Based on Weibull parameters obtained by using EGO, potential WE and potential annual revenue were estimated for Gdańsk, which is the capital of Pomerania Voivodeship in Poland, in the case of having city-type wind turbines in the city center. Estimations for Gdańsk showed that city-type wind turbines might be helpful for producing electricity from WE in the city without being limited by constraints such as having a long distance between wind turbines and buildings. If such wind turbines were erected on the roofs of residential buildings, malls, or office buildings, there is a possibility that part of the electric energy needed for such buildings could be generated using WE. However, this topic should be further investigated from technical and financial perspectives
Anionic states of C6Cl6 probed in electron transfer experiments
- Sarvesh Kumar
- Tymon Kilich
- Marta Łabuda
- Gustavo García
- Paulo Limão-Vieira
2022 Pełny tekst PHYSICAL CHEMISTRY CHEMICAL PHYSICS
This is the first comprehensive investigation on the anionic species formed in collisions of fast neutral potassium (K) atoms with neutral hexachlorobenzene (C6Cl6) molecules in the laboratory frame range from 10 up to 100 eV. In such ion-pair formation experiments, we also report a novel K+ energy loss spectrum obtained in the forward scattering giving evidence of the most accessible electronic states. The vertical electron affinity of (–3.76 ± 0.20) eV has been obtained and assigned to a purely repulsive transition from C6Cl6 ground state to a σCCl*state of the temporary negative ion yielding Cl– formation. These experimental findings have also been supported by state-of-the art theoretical calculations on the electronic structure of C6Cl6 in the presence of a potassium atom and used to help analyse the lowest unoccupied molecular orbitals participating in the collision process. From the time-of-flight mass spectra recorded in the wide collision energy range, more than 80% of the total anion yield is due to the undissociated parent anion C6Cl6 –, C6Cl5 – and Cl– formation. Other fragment anions that require complex internal reactions within the temporary negative ion formed after electron transfer, and accounting for less than 20% of the total yield, have been assigned to C6Cl4–, C3Cl2–, C2Cl– and Cl2–. The joint experimental and theoretical methodologies employed in these electron transfer studies, are the most comprehensive and unique assignments of the hexachlorobenzene anionic species and the role of C6Cl6 electronic states in collision induced dissociation to date.
Anonymus
- Krzysztof Wróblewski
2022
Impulsem do namalowania niewielkiego obrazu „Anonymous” były akcje przeprowadzone przez internetowe grupy hakerów, których celem było wspomagania Ukrainy w jej walce przeciwko militarnej agresji Rosji. Anonimowi aktywiści ukrywają twarze pod maską Guya Fawkesa, która rozpowszechniła się po 2006 roku wśród różnych grup protestacyjnych występujących przeciwko rządom, bankom i instytucjom finansowym. Maska chroni nie tylko tożsamość buntowników, ale symbolizuje też ich zjednoczenie we wspólnej sprawie. Aktywiści Anonymous nie są anarchistami lecz rebeliantami, którzy sprzeciwiają się ograniczaniu wolności oraz agresji. Świat tworzą i zmieniają dłonie miliardów ludzi, których twarze przybiera ją wielorakie maski. Skala ich dokonań ma różne rozmiary – od prawie niewidocznych po gigantyczne.