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1

Effect of electronic cigarette (EC) aerosols on particle size distribution in indoor air and in a radon chamber

Khalaf Hyam Nazmy, Mostafa Mostafa Y. A., Zhukovsky Michael

Nukleonika

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2019

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Vol. 64, No. 1

31--38

EN

Particle size distribution is an important factor governing whether aerosols can be deposited in various respiratory tract regions in humans. Recently, electronic cigarette (EC), as the alternative of tobacco cigarette, has become increasingly popular all over the world. However, emissions from ECs may contribute to both indoor and outdoor air pollution; moreover, comments about their safety remain controversial, and the number of users is increasing rapidly. In this investigation, aerosols were generated from ECs and studied in the indoor air and in a chamber under controlled conditions of radon concentration. The generated aerosols were characterized in terms of particle number concentrations, size, and activity distributions by using aerosol diffusion spectrometer (ADS), diffusion battery, and cascade impactor. The range of ADS assessment was from 10–3 µm to 10 µm. The number concentration of the injected aerosol particles was between 40 000 and 100 000 particles/cm3. The distribution of these particles was the most within the ultrafi ne particle size range (0–0.2 µm), and the other particle were in the size range from 0.3 µm to 1 µm. The surface area distribution and the mass size distribution are presented and compared with bimodal distribution. In the radon chamber, all distributions were clearly bimodal, as the free radon decay product was approximately 1 nm in diameter, with a fraction of 0.7 for a clean chamber (without any additional source of aerosols). The attached fraction with the aerosol particles from the ECs had a size not exceeding 1.0 µm.

2

Size distribution of ambient and radioactive aerosols formed by the shortlived radon progeny

Skubacz Krystian, Wołoszczuk Katarzyna

Journal of Sustainable Mining

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2019

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Vol. 18, iss. 2

61--66

EN

The survey of ambient airborne particle size distribution is important when the deposition of radioactive particles is considered in the human lung and the assessment of radiation hazard in occupational exposures or contaminated environments. CLOR (the Central Laboratory for Radiological Protection) in cooperation with CMI (the Central Mining Institute) performed simultaneous measurements of the activity size distribution of radon progeny and ambient aerosols using different types of aerosols. Measurements were performed in a radon chamber with a volume of 17m3, where radon was generated by a radium-226 open source, and ambient aerosols by an oil candle, vax candle, and incense sticks. Such measurements were also made in an aerosol depleted atmosphere after cleaning the chamber air by means of a high-efficiency pump and filters. The size distribution of radioactive aerosols containing radon progeny was measured by RPPSS (Radon Progeny Particle Size Spectrometer) with the measuring size ranging from 0.6 nm to approximately 2500 nm. The key parts of this device are the impaction plates and diffusion screen batteries, which collect aerosols of different sizes, and semiconductor alpha detectors which detect the activity of the collected particles. The SMPS (Scanning Mobility Particle Sizer Spectrometer) and APS (Aerodynamic Particle Sizer) were applied to evaluate the size distribution of all aerosols with sizes from approximately 3 nm to 20 μm. Based on the results obtained by these spectrometers, the activity size distributions and related dose conversion factors (DCF) were evaluated both for the exposed workers and the general population.

3

Temporal response of magnitude distribution to fluid injection rates in The Geysers geothermal field

Leptokaropoulos Konstantinos, Staszek Monika

Acta Geophysica

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2019

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Vol. 67, no. 1

327--339

EN

The influence of fluid injection rates on the magnitude distribution of the seismicity which occurred in the NW part of The Geysers geothermal site is studied here. A direct comparison between injection rate changes and b value response is attempted after appropriate selection of data subsets. Due to the relatively small sample (1121 events, corresponding to an average rate of ~ 0.45 events/day), we also aggregated seismic activity into two families corresponding to increasing and decreasing injection rates, respectively. The b values were calculated as a function of time lag related to the injection activity. In agreement with previous studies, we found a statistically significant direct relation between b values and injection rate changes, which occurred at a zero or very short time lag (from 0 to ~ 15 days). However, the b value changes are related to the slope (i.e., the second derivative of injection volume), instead of the absolute values of injection rates. The increasing injection rates correspond to b = 1.18 ± 0.06, whereas the decreasing injection rates correspond to b = 1.10 ± 0.05. The corresponding values estimated by the repeated medians technique are b = 1.97 ± 0.20 and b = 1.50 ± 0.13. Both differences are significant at 0.05 level.

4

Effect of torsional vibration on woodchip size distribution

Kaššay P.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2018

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z. 99

95--104

EN

Nowadays, there is increasing demand for the use of renewable energy sources such as woodchips. One of the important qualitative parameters of woodchips is the size distribution. The aim of this article is to determine the effect of a woodchipper disc’s torsional vibration on the evenness of woodchip length, as well as propose a mathematical solution to this problem by assuming one harmonic component of disc speed and the uniform feed of chipped material. The presented mathematical solution can be used to determine the unevenness of woodchip length when the parameters of torsional vibration are known.

5

Influence of liquid flowrate on size of nanobubbles generated by porous-membrane modules

Ulatowski K., Sobieszuk P.

Chemical and Process Engineering

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2018

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Vol. 39, nr 3

335–-345

EN

The aim of this work was to investigate the influence of distilled water flowrate in two different porousmembrane modules on the size of generated nitrogen nanobubbles. Modules had different diameter and number of membrane tubes inside the module. As bubbles are cut off from the membrane surface by a shear stress induced by the liquid flow, the change in the linear liquid velocity should result in a change of the generated bubble diameter. For both modules, higher flowrate of liquid induced generation of smaller bubbles, which was consistent with our expectations. This effect can help us in generation of bubbles of desired size.

6

Theory of the Stereological Analysis of Spheroid Size Distribution – Validation of the Equations

Gurgul D., Burbelko A., Wiktor T.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 4

67--72

EN

The paper presents validation tests for method which is used for the evaluation of the statistical distribution parameters for 3D particles’ diameters. The tested method, as source data, uses chord sets which are registered from a random cutting plane placed inside a sample space. In the sample space, there were individually generated three sets containing 3D virtual spheres. Each set had different Cumulative Distribution Function (CDF3) of the sphere diameters, namely: constant radius, normal distribution and bimodal distribution as a superposition of two normal distributions. It has been shown that having only a chord set it is possible, by using the tested method, to calculate the mean value of the outer sphere areas. For the sets of data, a chord method generates quite large errors for around 10% of the smallest nodules in the analysed population. With the increase of the nodule radii, the estimation errors decrease. The tested method may be applied to foundry issues e.g. for the estimation of gas pore sizes in castings or for the estimation of nodule graphite sizes in ductile cast iron.

7

Time-dependent seismic hazard in Bobrek coal mine, Poland, assuming different magnitude distribution estimations

Leptokaropoulos K., Staszek M., Cielesta Sz., Urban P., Olszewska D., Lizurek G.

Acta Geophysica

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2017

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Vol. 65, no. 3

493--505

EN

The purpose of this study is to evaluate seismic hazard parameters in connection with the evolution of mining operations and seismic activity. The time-dependent hazard parameters to be estimated are activity rate, Gutenberg–Richter b-value, mean return period and exceedance probability of a prescribed magnitude for selected time windows related with the advance of the mining front. Four magnitude distribution estimation methods are applied and the results obtained from each one are compared with each other. Those approaches are maximum likelihood using the unbounded and upper bounded Gutenberg–Richter law and the non-parametric unbounded and non-parametric upper-bounded kernel estimation of magnitude distribution. The method is applied for seismicity occurred in the longwall mining of panel 3 in coal seam 503 in Bobrek colliery in Upper Silesia Coal Basin, Poland, during 2009–2010. Applications are performed in the recently established Web-Platform for Anthropogenic Seismicity Research, available at https://tcs.ah-epos.eu/

8

Effects of fuel tracing on nanoparticles from a Diesel engine

Czerwinski J., Mayer A., Wischer A.

Combustion Engines

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2015

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R. 54, nr 1

3--10

EN

Nanoparticles from a HD-Diesel engine and their composition were investigated in the present paper. Three variants of fuel additivities were applied to allow the balances of certain tracer-substances after the tests: 2% of additives-free lube oil; 2% of market lube oil with additive package and Fe-based regeneration additive (FBC) with 40 ppm Fe. The analysed SMPS particle size distributions indicated that by blending of the market lube oil to the fuel the combined effects of metals or metal oxides from the additive packages and of the heavy HC’s from the lube oil matrix contribute the most to the increase of nuclei mode. From the masses of Fe, Zn and Ca, which were introduced with the fuel, only parts were found as integral masses at all ELPI-stages – Fe 43.5%, Zn 36.6%, Ca 65.5%. The majority of mass of some metals, or metal oxides emissions on ELPI-stages (up to 80%) is in the size ranges below 100 nm.

9

Analysis of the size of dust particles which were formed during pellet production

Czachor G., Bohdziewicz J., Gryszkin A.

Agricultural Engineering

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2014

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Vol. 18, No. 2

55--63

EN

The objective of the paper was to analyse by means a laser diffraction method, the granulometric composition of dust which settled on various surfaces of factory floors, where pellet was produced. A laser analyser of the size of particles MASTERSIZER 2000 was used in the research. Based on the research, it was found out that the sample of dust contained a limited amount of fractions particularly dangerous for health, i.e. PM4 and PM10 respectively 1.4% and 5.1%. The content of particles of dimension up to 100 μm did not exceed 60% of total volume of the analysed dust. Moreover, a shape of particles was analysed with the use of optic and scanning microscope and NIS –Elements BR software. Values of shape coefficients and histograms of their distribution were determined. Furthermore, relations between the size of particles and its shape were described.

PL

Celem pracy była analiza metodą dyfrakcji laserowej składu granulometrycznego pyłów osiadłych na różnych powierzchniach hal, w których produkowano pelet. W badaniach wykorzystano laserowy analizator wielkości cząstek model MASTERSIZER 2000. Na podstawie badań stwierdzono, że próbki pyłu zawierały ograniczone ilości frakcji szczególnie niebezpiecznych dla zdrowia, tj. PM4 oraz PM10 odpowiednio 1,4% oraz 5,1%. Zawartość cząstek o wymiarach do 100 μm nie przekraczała 60% ogólnej objętości analizowanego pyłu. Analizowano również kształt cząstek z wykorzystaniem mikroskopu optycznego i skaningowego oraz oprogramowania NIS-Elements BR. Wyznaczono wartości współczynników kształtu oraz określono histogramy ich rozkładu. Określono również zależności zachodzące pomiędzy rozmiarem cząstek a jej kształtem.

10

Delivery of nebulised drugs using endotracheal tube

Penconek A., Odziomek M., Niedzielska A., Moskal A.

Chemical and Process Engineering

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2012

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Vol. 33, nr 4

689--696

EN

The purpose of the studies was to estimate efficiency of delivering nebulised drugs into the lower respiratory tract through endotracheal tubes (ET tubes) which are commonly used in the treatment of uncooperative patients. Water solution of Disodium Cromoglycate (DSCG) was nebulised with a constant air flow (25 l/min). Experimental studies were done for eight ET tubes with varying sizes (internal diameter, length) and made of two different materials. Size distribution of aerosol leaving ET tubes was determined with the use of aerosol spectrometer. Fine Particle Fraction (FPF) and Mass Median Aerodynamic Diameter (MMAD) were calculated for the aerosol leaving each tube. Additionally, mass of the Disodium Cromoglycate deposited into each endotracheal tube was determined. ET tubes can significantly influence the parameters of delivered aerosol depending on their diameter. FPF of aerosol delivered in to the respiratory tract is lower if small endotracheal tubes are used. However, MMAD and FPF for large endotracheal tubes are almost identical with MMAD and FPF from nebuliser. The results indicate that a substantial fraction of large droplets is eliminated from the aerosol stream in long endotracheal tubes (270 mm). In this case the mass of drug delivered through ET tubes is reduced but the content of small droplets increases (high value of FPF).

11

Nanoparticle number from biodiesel blends combustion in a common rail fuel injection system diesel engine equipped with exhaust gas recirculation

Harland J.

Silniki Spalinowe

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2009

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R. 48, nr 3

28-36

EN

The paper presents characterisations of nanoparticle number in exhaust gases from biodiesel blends (B30, 30% of RME by volume with ultra low sulphur diesel fuel, ULSD) combustion in a V6 diesel engine equipped with a common rail fuel injection system. The engine was operated on three steady-state test points extracted from the New European Driving Cycle without engine hardware or the engine management system (EMS) modification. A fast differential mobility spectrometer was used to determine particle number size distribution based on electrical mobility equivalent diameter. The distribution was dependent on the engine operating condition and the rate of exhaust gas recirculation (EGR). The particle size in the nucleation mode from B30 combustion with and without EGR is smaller than that of ULSD while giving higher number concentration for all engine operating conditions tested. However, in the accumulation mode with and without EGR, the smaller sizes and the lower total numbers from B30 combustion were observed. For both fuels, EGR shows insignificant changes to the primary particle size but noticeable increase in particle size and number in the accumulation mode. In overall, compared to the ULSD case, the B30 combustion reduced particle size and lowered total particle number in exhaust gas emitted from the engine with EGR.

PL

W artykule przedstawiono charakterystykę ilościową nanocząstek w gazach spalinowych ze spalania mieszanek z biodieslem (B30, mieszanka 30% obj. estru metylowego oleju rzepakowego RME z ultraniskosiarkowym olejem napędowym ULSD) w silniku z zapłonem samoczynnym V6 wyposażonym w układ wtryskowy z ciśnieniowym kolektorem paliwa common rail. Badania przeprowadzono w trzech ustalonych stanach obciążenia, wyjętych z Nowego Cyklu Europejskiego, bez modyfikacji systemu silnika oraz układu sterowania silnikiem EMS. Szybki różnicowy spektrometr mobilności DMS zastosowano do określenia rozkładu ilościowego cząsteczek, opartego na równoważnej średnicy mobilności elektrycznej. Rozkład okazał się zależny od stanu operacyjnego silnika i stopnia recyrkulacji spalin EGR. Wymiary cząstek w zakresie nukleacyjnym przy spalaniu paliwa B30 z udziałem i bez udziału EGR są mniejsze niż przy spalaniu ULSD, natomiast ich koncentracja ilościowa jest większa we wszystkich badanych stanach operacyjnych silnika. Natomiast w zakresie akumulacyjnym zaobserwowano mniejsze wymiary i mniejszą całkowitą liczbe cząstek przy spalaniu B30, zarówno z udziałem, jak i bez udziału recyrkulacji spalin EGR. Dla obydwu paliw zastosowanie EGR powoduje nieznaczne zmiany w wymiarach cząstek pierwotnych, lecz znaczący wzrost wymiarów i liczby cząstek w zakresie akumulacyjnym. Ogólnie biorąc, w porównaniu ze spalaniem ULSD spalanie mieszanki B30 spowodowało zmniejszenie wymiarów cząstek i obniżenie całkowitej ich ilości w gazach spalinowych z silnika pracującego z udziałem recyrkulacji spalin EGR.

12

Bubble size distribution of foam

Den Engelsen C. W., Isarin J. C., Gooijer H., Warmoeskerken M. M. C. G., Groot Wassink J. G.

Autex Research Journal

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2002

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Vol. 2, no. 1

14--27

EN

A procedure based upon image analysis has been adopted to study the influence of several physical parameters on bubble size in foam. A procedure has been described to account for the distribution of bubble size. Foam was generated in a rotor-stator mixer. In the present research, the nature of the surfactant, liquid viscosity, solid phase content, and rotational speed of the mixer were varied. All parameters were found to influence the bubble size and its distribution to a certain extent. These effects were qualified experimentally.

13

Właściwości emisji pyłu i metali ciężkich w procesie spalania węgla w paleniskach domowych

Hławiczka S., Kubica K., Zielonka U., Wilkosz K.

Archiwum Ochrony Środowiska

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2001

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Vol. 27, no. 2

29-45

PL

Wykonano badania składu frakcyjnego pyłów emitowanych z procesu spalania węgla kamiennego w paleniskach domowych oraz badania uwalniania się rtęci, cynku, ołowiu I miedzi z węgla spalanego w tych źródłach. Emisje metali charakteryzowano przez wyznaczanie współczynników podziału (K), który wyraża stosunek mas metalu emitowanego do powietrza do masy metalu zawartej w jednostkowej ilości węgla przed spalaniem. Wyznaczone wartości (K) cynku, ołowiu i miedzi wynosiły odpowiednio 0,59, 0,33 i 0,34 ze współczynnikami zmienności tego parametru wynoszącymi odpowiednio 37, 46 i 44%. Dużo lepszą powtarzalność wartości (K), wynoszącą 17% uzyskano w przypadku Hg. Stwierdzono, Ze w procesie spalania węgla kamiennego w paleniskach domowych 52% rtęci zawartej w węglu emitowane jest do powietrza w postaci gazowej. Badania emisji pyłu z palenisk domowych wykazały, że w poszczególnych frakcjach pyłów emitowanych z 7 badanych źródeł spalania przeważały emisje frakcji drobnych, Średnio około 76% emitowanych pyłów mieściło się we frakcjach o wymiarach ziaren do 12 um czyli należących do frakcji pyłu zawieszonego. Udział frakcji ziaren w zakresie od 12 do 29 um wynosił 9%.Dane te wskazują, że oddziaływanie emisji pyłów z tych źródeł nie ogranicza się do zasięgów lokalnych, lecz pyły te i zawarte w nich metale mogą być przenoszone w atmosferze na znaczne odległości.

EN

Size distribution of particulate matter (PM) emitted from coal combustion in residential furnaces as well as emission of Hg, Zn, Pb and Cu were investigated. The metals emission was characterized by partition factors. The factor expresses the distribution of metal streams between the feed coal and its combustion products emitted to the atmosphere. The values of factors for Zn, Pb and Cu were 0,59, 0,34 respectively; the relevant variance coefficients were 37, 46 and 44%. Much better variance coefficient of factor (17%) appeared in the case of mercury. It was found that 52% of Hg in feed coal was emitted to the air in gaseous from. Particulate matter emission from 7 coal combustion sources was investigated and fine particles were found as the main fraction. About 76% of PM were emitted as the size fractions up to 12 um. The share of size fractions between 12-29 um was 9%. It means that the impact of PM emission from residential furnaces is not of local scale but the particles containing heavy metals can be transported on long distances in the atmosphere.