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Number of results: 163
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Keywords emission
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Abstract

The simplified model of the gas emission from cars in the city is presented. The model is based on the Pasquille relation with necessary modifications regarding diffusion in the perpendicular direction to the street axis and the emission in the upper limit of the street. The emission cars from going down the street is modelled as the series of sources located close to the street level, with the emission related to the number and size of the car engine. The emission from sources of pollution located outside the street is modelled as the system of sources of pollution located on the height of the buildings along the street. Some examples showing the influence of the wind velocity and air turbulence on the carbon monoxide concentration along the length and the height of the street are presented.
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Authors and Affiliations

Marek Janusz
Jan Nadziakiewicz
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Abstract

An analysis of the methods used in Bulgaria for estimating CO2, SO2 and dust emissions has been conducted. The first methodology, which is officially used by all energy auditors at the Agency for Sustainable Energy Development targets the energy efficiency of combustion devices installed mainly at industrial enterprises. The second methodology, used by the Ministry of Environment and Water, is more comprehensive and can be applied to thermal power plants, small combustion plants as well as industrial systems. In recent years, many projects related to energy efficiency and renewable energy projects, including hydrogen technologies, which require an assessment of reduced greenhouse gas emissions, have been implemented as a priority. The use of reliable and accurate methods is essential in the assessment of greenhouse emissions. A novel methodology, based on stoichiometric equations of the combustion process for solid, liquid and gaseous fuels has been proposed and comprised. This novel methodology is characterized by higher precision compared to the methods currently in place and this is achieved through calculating emissions from the combustion of energy fuels accounting for the full elemental composition of the fuel and its heating value, whereas the current commonly applied methods use only the fuel type and the carbon content. A further benefit of the proposed methodology is the ability to estimate emissions of fuels for which there is no alternative method for calculating CO2, SO2 and dust. Results of emission calculations according to the analysed methods are presented. Finally, a comparative analysis between the presented methodologies including an assessment of their accuracy and universal applicability has been made.
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Authors and Affiliations

Iliya Krastev Iliev
1
Hristo Ivanov Beloev
1
Diana Ivanova Ilieva
2
Janusz Badur
3

  1. University of Ruse, Heat, Hydraulics and Environmental Engineering, Studentska 8, 7017 Ruse, Bulgaria
  2. University of Telecommunications and Post, Akad. Stefan Mladenov 1, 1700 Sofia, Bulgaria
  3. Energy Conversion Department, Institute of Fluid Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-251 Gdansk, Poland
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Abstract

The paper presents a numerical model of car exhaust pollutant dispersion. The model can be used for estimation of the impact of pollutant emissions from road vehicles on the environment. The finite volume method has been used for model formulation. Equations obtained after discretisation are solved by using different methods like Runge-Kutta, Crank-Nicholson or decomposition methods. On the basis of the numerical simulation, conclusions are formulated about the numerical effectiveness of the integration methods used. In the paper, a problem of nitrogen oxides dispersion is formulated and solved, whereby chemical reactions are included in considerations. The model presented in the paper has been used for numerical calculations of car exhaust pollutant concentrations in a real car park. The last part of the paper presents some numerical results of calculations, which include emissions after cold start of engines.
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Authors and Affiliations

Krzysztof Brzozowski
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Abstract

This article presents data on the anthropogenic air emissions of selected substances (CO2, SO2, total suspended particles (TSP), dioxins

and furans (PCDD/F), Pb and Cd) subject to reporting under the Climate Convention (UNFCCC) or the Convention on Long-range

Transboundary Air Pollution (UNECE CLRTAP). It also presents the national emissions of these substances in 2014 by the major source

categories and defines the share of metal production in these emissions. Analysis is based on national emission inventory reports. Most

important source of air emission in case of CO2 and SO2 is 1.A.1 Energy industries category. TSP and PCDD/F are emitted mainly from

fuel combustion in small sources (i.a. households). Emission of heavy metals (Pb and Cd) is connected mostly with 1.A.2. Manufacturing

industries and construction category. Metallurgy is significant source of emission only for lead and cadmium from among all considered

substances. The shares of particular sectors in the national emissions of given pollutants are important, in view of the possible reduction

measures and the determination in which industries they could bring about tangible results.

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Authors and Affiliations

I. Kargulewicz
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Abstract

Natural gas combustion was carried out in air enriched with oxygen in the amount of 25 and 29% with addition of CO2 in place of part of nitrogen. The research was carried out at different flow rates of gas and oxygen excess ratios. The concentration of CO and NOx was analyzed. It has not been proved that the increased oxygen concentration influences significantly the CO concentration. However, the addition of CO2 caused a substantial variability of CO concentration in the exhaust gas, in contrast to the concentration of NOx which decreased monotonically. Model calculations, performed with use of FactSage, indicate an increase in the concentration of CO not only for the air enriched with oxygen, but after adding CO2 too, as well

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Authors and Affiliations

Zofia Kalicka
Wojciech Jerzak
Elżbieta Kawecka-Cebula
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Abstract

Agriculture is a signifi cant source of gaseous pollutants such as ammonia, methane, nitrous oxide and volatile organic compounds. Ammonia is particularly important due to the high emission and local, as well as global impact on the environment. The release of NH3 is one of the main ways of nitrogen emission to the atmosphere and it contributes to its subsequent deposition. The aim of the study was to analyze ammonia emissions from animal production in Poland in 2005–2017, its regional diversity and possibilities of its reduction in agriculture. The ammonia emission was calculated for the animal production groups according to the NFR classifi cation. The values of ammonia emission were calculated based on ammonia emission factors used by KOBIZE, in accordance with the EMEP/EEA methods. In 2017, the NH3 emission from Polish agriculture amounted 288 Gg and it accounted for 96% of the emission in 2005. Ammonia emission from livestock production, in 2005–2017, on average accounted for 79.8% of agricultural emissions. The largest share had the cattle (51%) and swine (30%) production. The NH3 emissions differed strongly between provinces. The emission density (kg NH3·km-2·year-1) in provinces with intensive livestock production was about 5.5 times higher than in regions, where livestock production was the lowest. The mitigation strategies should be implemented primarily in provinces where reduction potential is the largest. The assessment of the reduction potential should take into account the NH3 emission per 1 km2 and the low

NH3 emission technologies, which are already applied in the regions.

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Authors and Affiliations

Paulina Mielcarek-Bocheńska
Wojciech Rzeźnik
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Abstract

CO, NO, NO2 and dust concentrations from combustion of deciduous wood (birch, beech, lime-tree) logs and pellets in two heating boilers (15 and 25 KW), situated in a heat station were investigated. Time dependences of pollutant concentrations as well as the impact of temperature in the combustion chamber and oxygen concentration on pollutant concentrations were presented. Pollutant emission indices have been estimated.

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Authors and Affiliations

Marek Juszczak
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Abstract

The primary methods of reducing nitrogen oxides, despite the development of more advanced technologies, will continue to be the basis for NOx reduction. This paper presents the results of multivariate numerical studies on the impact of air staging on the flue gas temperature and composition, as well as on NOx emissions in a OP 230 boiler furnace. A numerical model of the furnace and the platen superheater was validated based on measurements using a 0-dimensional model of the boiler. Numerical simulations were performed using the ANSYS Workbench package. It is shown that changes in the distribution of air to OFA nozzles, the angle of the air outflow from the nozzles and the nozzle location involve a change in the flue gas temperature and in the volume of NOx and CO emissions at the furnace outlet.
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Authors and Affiliations

Bartłomiej Hernik
Katarzyna Jagodzińska
Dominik Matuszek
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Abstract

Most automotive electronic components can cause electromagnetic interference, that can cause power electronic circuits to become unstable. As per electromagnetic compatibility (EMC) standards, these electronic circuits should meet the specifications which are not achieved under some conditions. In this paper, the conducted emissions (CEs) are generated due to the switching of a buck converter, which often occurs in automotive electronics. The noise source was found to be due to the presence of common mode currents which largely affects the performance of EMC. Two types of filtering techniques were analysed and designed, and the results were compared to find an effective filtering solution to mitigate the effects of CE due to a common mode noise for the frequency range from 150 kHz to 108 MHz according to the International Special Committee on Radio Interference (CISPR25) standard. The capacitive and parasitic impedance were calculated and then used in the simulation. Finally, the simulated and measured results are presented. The noise level can be minimized by as much as 50 dB, which is an efficient noise reduction value.
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Authors and Affiliations

G. V. Aswini
1
ORCID: ORCID
S. Chenthurpandian
1

  1. Department of Electronics and Communication Engineering, SNS College of Technology, Coimbatore-641035, India
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Abstract

The uncertainty in the supply of crude oil, increasing the number of vehicles and rising air pollution, especially in urban areas, has prompted us to look for alternative fuels. It is understood that using Compressed Natural Gas (CNG) in IC engines could be a mid-term solution to these problems. It is well established that CNG has better combustion characteristics and low emissions compared to conventional gasoline and diesel fuel. In the present study, an experiment was conducted to evaluate the engine performance and exhaust emissions using various percentages of CNG in dual fuel mode. CNG was mixed in the intake manifold’s air stream, and diesel was injected after the compression of the CNG air mixture. This paper presents experimental results of 40%,60%, and 80% CNG in the air stream. Engine performance and emissions are presented and discussed at a speed of 1200 rpm to 1500 rpm in steps of 50 rpm. The results of the experiments showed that adding CNG to diesel engines in dual-fuel combustion significantly impacted performance and emissions. Compared to single diesel fuel combustion, dual fuel combustion increases brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) at all CNG energy shares and engine speeds. Carbon monoxide (CO) and hydrocarbon (HC) emissions were increased, while nitrogen oxide (NOX) and smoke opacity were decreased in dual fuel combustion compared to single diesel fuel.
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Bibliography

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Authors and Affiliations

Neeraj Kumar
1
ORCID: ORCID
Bharat Bhushan Arora
ORCID: ORCID
Sagar Maji
1
ORCID: ORCID

  1. Delhi Technological University, Delhi, India
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Abstract

The article has presented the assumptions underlying the organization of emissions trading of greenhouse gases with a particular emphasis on CO2 emission allowances. Through the analysis of the literature, international activities were undertaken aimed at reducing greenhouse gas emissions into the atmosphere, starting from the First World Climate Conference organized in 1979. The origins and guidelines of the Kyoto Protocol were also given considerable attention. In addition to the description of the key assumptions of the Protocol and its main components, the characteristics of international trade in Kyoto units were also included. The mechanisms involved in international trade and the types of units traded in a detailed manner are described. In the next part of the article, emission trading systems operating in the world are characterized. In the second part of the paper special attention was paid to the conditionings of the European market, i.e. European Emissions Trading System – EU ETS. Historical events were presented that gave rise to the creation of the EU ETS. In the next steps, the types of units that are tradable were described. Furthermore, the trade commodity exchanges on which trade is conducted, the key factors determining the price of individual allowances are also indicated. In the last part of the article, relatively recent issues – the IED Directive and the BAT conclusions have been pointed out. Referring to the applicable regulations, the impact of their implementation on the situation of entities obliged to limit greenhouse gas emissions was analyzed. In the final phase, an attempt was made to assess the impact of IED and BAT to electricity prices.

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Authors and Affiliations

Dawid Ciężki
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Abstract

Photofield emission from SiGe nanoislands formed by molecular beam epitaxy (MBE) have been investigated. Two types of nanoislands, namely the domes and pyramids with different heights, have been addressed. It was found that the arrays of SiGe nanoislands exhibited a low onset voltage for field emission. The increase of emission current and the decrease of the curve slope in Fowler-Nordheim coordinates under green light illumination have been revealed. Electron field emission and photoemission from SiGe nanoislands have been explained based on the energy band diagram of Si-Ge heterostructure and some energy barriers have been determined.

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Authors and Affiliations

O. Steblova
A. Evtukh
O. Yilmazoglu
V. Yukhymchuk
H. Hartnagel
H. Mimura
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Abstract

The occurrence of trace elements in coal and their concentration ranges are presented. The paper describes the origin of trace elements in coal, modes of accumulation, binding with mineral and organic matter as well as their behaviour during combustion. The presence of trace elements of coal origin should be taken into consideration when evaluating harmful impact of coal-fired fewnaces due to significant concentration of fly ash from combustion in suspended dust On the basis of analytical data emission of 15 trace elements from coal combustion in Poland is presented.
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Authors and Affiliations

Joanna Staisz
Anna Pasoń-Konieczyńska
Jan Konieczyński
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Abstract

This study investigates cadmium (Cd) accumulation in the plant leaves of juglans regia (walnut) and cydonia oblanga (quince) trees related to traffic emissions on the highway roadside. The plant leaf samples were collected from 20 sites on the D-100 Highway roadside and washed with deionized water before analyzed. Determination of Cd was carried out using an inductively-coupled plasma-mass spectrometer after microwave digestion of the samples. Cd concentration on the plant leaves was found to be between 0.04–0.11 mg/kg. In order to determine the traffic-based emissions, vehicles were counted and an emission inventory was prepared. 0.18 tons of Cd was found to be delivered into the atmosphere every day. Cd accumulation depends on traffic density because there were no residential area and industrial plants. The distribution of Cd accumulation caused by traffic emissions was mapped by using a geographic information system (GIS). The maps showed that the Cd accumulation was high in the areas near the highway and then gradually decreased by moving away from the highway.

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Authors and Affiliations

Merve Çolak
Mahnaz Gümrükçüoğlu
Füsun Boysan
Erkan Baysal
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Abstract

Szargut proposed the algorithm for determination of the influence of irreversibility of components of thermal process on the emission of CO2 [6]. In the presented paper, basing on Szargut's proposal, the example of analysis of influence of operational parameters of coal fired power plant on the local increase of CO2 emission is presented. The influence of operational parameters on the local exergy losses appearing in components of investigated power plant are simulating making use of the semi-empirical model of power plant.

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Authors and Affiliations

Wojciech Stanek
Michał Budnik
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Abstract

The paper presents a concept of producing energy on the basis of modern alternative fuels to be burnt in low- and medium-power stokerfired boilers. The thermal energy contained in water vapour and hot water will be utilized in producing, in combination, of electrical energy, and for heating of cubature objects. Modern alternative fuels in the form of briquettes and pellets will be produced from hard coals and municipal waste other than hazardous. There have been presented the properties of alternative fuels obtained, and the concept of their utilization in the process of energy production in cogeneration.

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Authors and Affiliations

Eugeniusz Orszulik
Jan Jachyra
Andrzej Wasylewicz
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Abstract

Zawartość cynku w glebach wokół huty cynku ,,Miasteczko Śląskie”
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Authors and Affiliations

Edyta Sierka
Bernard Palowski
Tadeusz Kimsa
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Abstract

An acoustic emission method (AE) is widespread and often applied for partial discharge (PD) diagnostics, mainly due to its ease of application as well as noninvasiveness and relatively high sensitivity. This paper presents comparative analysis of AE signals measurement results archived under laboratory conditions as well as on-site actual AE signals generated by inside PDs in electrical power transformer during its normal service. Three different PD model sources are applied for laboratory research: point to point, multipoint to plate and surface type. A typical measuring set up commonly used for on-site transformer PD diagnostics is provided for the laboratory tasks: piezoelectric joint transducer, preamplifier, amplifier and measuring PC interface. During the on-site research there are three measuring tracks applied simultaneously. Time domain, time-frequency domain and statistical tools are used for registered AE signals analysis. A number of descriptors are proposed as a result of the analysis. In the paper, at- tempt of AE signals descriptors, archived under laboratory condition application possibilities for on-site PD diagnostics of power transformers during normal service is made.
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Authors and Affiliations

Michał Kunicki
Andrzej Cichoń
Sebastian Borucki
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Abstract

Tests for combustion of hay and sunflower husk pellets mixed with wood pellets were performed in a horizontal-feed as well as under-feed (retort) wood pellet furnace installed in boilers with a nominal heat output of 15 and 20 kW, located in a heat station. During the combustion a slagging phenomenon was observed in the furnaces. In order to lower the temperature in the furnace, fuel feeding rate was reduced with unaltered air stream rate. The higher the proportion of wood pellets in the mixture the lower carbon monoxide concentration. The following results of carbon monoxide concentration (in mg/m3 presented for 10% O2 content in flue gas) for different furnaces and fuel mixtures (proportion in wt%) were obtained: horizontal-feed furnace supplied with hay/wood: 0/100 - 326; 30/70 - 157; 50/50 - 301; 100/0 - 3300; horizontal-feed furnace supplied with sunflower husk/wood: 50/50 - 1062; 67/33 - 1721; 100/0 - 3775; under-feed (retort) furnace supplied with hay/wood: 0/100 - 90; 15/85 - 157; 30/70 - 135; 50/50 - 5179; under-feed furnace supplied with sunflower husk/wood: 67/33 - 2498; 100/0 - 3128. Boiler heat output and heat efficiency was low: 7 to 13 kW and about 55%, respectively, for the boiler with horizontal-feed furnace and 9 to 14 kW and 64%, respectively, for the boiler with under-feed furnace.

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Authors and Affiliations

Marek Juszczak
Katarzyna Lossy
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Abstract

The impact of the fuel feeding mode (continuous or periodic with different stand-by/operation time ratios) on carbon monoxide (CO) and nitrogen oxides (NO, NOx) concentration values in the flue gas was analysed for coniferous wood pellet firing. Experiments were performed in a 25 kW water boiler equipped with an over-fed wood pellet furnace located in a full scale heat station simulating real-life conditions. Influence of oxygen concentration and temperature in the combustion chamber on carbon monoxide and nitrogen oxide concentrations was presented in diagrams. Dust and hydrocarbon concentrations were also monitored. It was concluded that the commonly used periodic fuel supply does not necessarily cause a significant increase of carbon monoxide concentration, as compared to the continuous fuel feeding mode. Continuous fuel supply can even induce higher carbon monoxide concentrations when fuel mass stream is not chosen properly. Each time new fuel type is used in a specific furnace, one should perform experiments to determine the adequate settings (stand-by/operation time ratio, fuel mass streams, air stream) to obtain the optimal, lowest possible emission for a certain boiler heat output

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Authors and Affiliations

Marek Juszczak
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Abstract

Results of the study examining carbon monoxide and nitric oxide concentrations while burning different types of agricultural biomass: coffee husk pellets alone or in combination with wheat straw pellets and cherry stones, sewage sludge pellets, corn stover briquettes and a mixture of rye straw briquettes and miscanthus briquettes were presented. The combustion was performed in a 50 kW boiler type Biowarmer with a cast-iron moving step grate. The temperature in the combustion chamber did not exceed 800 ◦C. For all biomass types, only brittle slag was generated in the furnace, which was easily broken by a reciprocating movement of the grate. Carbon monoxide concentration in the flue gas except for the case of sewage sludge pellet firing did not exceed the permitted value of 3000 mg/m3 and nitric oxide concentration 515 mg/m3, both presented for 10% O2 concentration in the flue gas based in dry gas. Hydrocarbon concentrations for all test runs were close to zero.
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Authors and Affiliations

Katarzyna Pałaszyńska
Marek Juszczak
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Abstract

The problem of harmful casting resins has been present in foundries for many years. Manufacturers are introducing new products that contain in their composition environmentally and eco-friendly ingredients. Unfortunately, not all types of technology can be used, sometimes environmental benefits are disproportionate to the quality of castings and their price. In the foundry industry, the most popular binders are based on organic compounds (often carcinogenic) and other harmful substances. Due to strict legal regulations regarding environmental protection, as well as care for the foundry's workers' comfort - their occurrence should be reduce to a minimum. These compounds often behave also depending on the conditions of use (temperature, atmosphere). The application of various methods of thermal analysis and spectroscopic methods allows to verify the mechanism of resin decomposition process in relation to conditions in the form in both inert and oxidizing atmosphere. For analysis the resins from cold-box technology, were used TG–DTG–DSC, Py-GC/MS methods and specified the course of changes occurring in combination of different atmosphere.

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Authors and Affiliations

S. Żymankowska-Kumon
K. Kaczmarska
B. Grabowska
A. Bobrowski
S. Cukrowicz
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Abstract

Non-invasive damage monitoring of concrete structures by means of Acoustic Emission (AE) requires multitransducers, multi-channel acquisition, high sampling frequency and long observation time. Owing to its propagation in concrete, the signal from AE reduces its amplitude during the propagation, and, consequently, some events can be lost due to lower signal intensity than the trigger level set on one sensor only. The innovative proposal discussed in the paper consists in the introduction of a Flat Amplifier and Trigger generator block (FAT) in order to generate a logical trigger when the AE is detected by any transducer. Experimental tests confirm the effectiveness of the FAT to acquire all the AE events and to increase the evaluation accuracy of damage indexes.

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Authors and Affiliations

Francesco Lamonaca
Antonio Carrozzini
Domenico Grimaldi
Renato Sante Olivito
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Abstract

The paper deals with the preparation and measurement of an experimental polymer graphite cathode that

seems to be a promising and cheap source of electrons utilizing cold field-emission in high- and ultra-high

vacuum. Polymer graphite seems to be a proper material as it contains a large amount of hybridized carbon

with a low degree of surface oxidation and silicon monoxide (SiO). Within the frame of this work, a special

experimental method of tip preparation has been designed and tuned. This method is based on ion milling

inside a dual-beam electron microscope enabling to obtain ultra-sharp tips of a diameter smaller than 100 nm

with a predefined opening angle. The charge transport within experimental samples is evaluated based on

results provided by the noise spectroscopy of the total emission current in the time and frequency domains.

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Authors and Affiliations

Alexandr Knápek
Miroslav Horáček
Jana Chlumská
Tomáš Kuparowitz
Dinara Sobola
Josef Šikula

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