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EN
The modern global milk processing industry involves the use of innovations and optimization of existing industry management methods, which contributes to the realization of sustainable development and energy efficiency. Increasing the energy efficiency of dispersing and homogenizing milk and dairy products can contribute to the practical implementation of the philosophy of the "European Green Deal". The jet-slot milk homogenizer is one of the most energy-efficient among all types of homogenizers in the dairy industry. The principle of its operation is based on the creation of a maximum speed difference between the fat balls of cream and the flow of skimmed milk. This makes it possible to obtain a high degree of dispersion with high energy efficiency of the process. Reducing the specific energy consumption and finding the optimal parameters of the homogenizer were based on the results of both theoretical and experimental studies and were carried out graphically. The optimization criteria (decreasing specific energy consumption while maintaining high homogenization quality) were chosen to achieve a dispersion of 0.8 μm with minimal energy consumption. The diameter of the confusor is optimized at the point of greatest narrowing. The obtained results indicate that to increase the energy efficiency of homogenization, the parameter values should be within 3.5–4.0 mm. The parameters of the width of the ring gap, the fat content and the speed of the cream are optimized. The results showed that it is possible to reduce the specific energy intensity of the process to values of 0.88–0.92 kWh/t when using cream with a fat content of 33–43%, which should be fed through an annular gap with a width of 0.6–0.8 mm. Optimum values of the cream feed speed were found, which should be equal to 7–11 m/s. The research results are of high practical value for the further development of an energy-efficient industrial model of a jet-slot homogenizer.
EN
The process of dispersion of a component in a given medium such as air is determined by three groups of factors: microclimatic, topographical and technical. The shape of the emitted pollutant plume depends on the parameters of the emitter and the volume of the air masses. This article describes five types of plume: looping, conical, ventilating, tracing and contaminating. Vertical air stability is an important physical parameter of the atmosphere. Three states of this parameter are described in this paper: inversion, convection and isotherm. The degree of pollutant dispersion is influenced by air temperature, shaping physical and chemical processes that include coagulation, sorption and diffusion. Topographical factors include landform type, land cover and development. A significant number of obstacles interfere with the free flow of air through a given area. Technical factors relate to the emitter parameters (altitude, diameter) and the nature of its operation (time, temperature, speed of pollutants at discharge). Emissions can come from a large pointsource emitter or from multiple diffuse emitters. Meteorological factors were found to have a decisive influence, as climatic parameters are subject to the greatest changes due to atmospheric turbulence, vertical temperature gradient, wind effect and precipitation.
PL
Proces rozpraszania składnika w danym ośrodku, jakim jest powietrze, jest uwarunkowany trzema grupami czynników: mikroklimatycznymi, topograficznymi oraz technicznymi. Kształt wyemitowanej smugi zanieczyszczeń zależy od parametrów emitora oraz od objętości mas powietrza. W artykule opisano pięć typów smug: pętlowy, stożkowy, wentylacyjny, trasujący i zanieczyszczający. Pionowa stateczność powietrza jest ważnym parametrem fizycznym atmosfery. W pracy zostały opisane trzy stany tego parametru: inwersja, konwekcja i izotermia. Na stopień dyspersji zanieczyszczeń wpływa temperatura powietrza, kształtująca procesy fizyczne oraz chemiczne, do których należą koagulacja, sorpcja oraz dyfuzja. Do czynników topograficznych zalicza się typ ukształtowania terenu, jego pokrycie oraz zagospodarowanie. Duża liczba przeszkód zaburza swobodny przepływ powietrza przez dany obszar. Czynniki techniczne dotyczą parametrów emitora (wysokość, średnica) oraz charakteru jego pracy (czas, temperatura, prędkość zanieczyszczeń na wylocie). Emisja może pochodzić z dużego emitora punktowego lub z wielu rozproszonych emitorów. Stwierdzono, że decydujący wpływ mają czynniki meteorologiczne, gdyż parametry klimatyczne podlegają największym zmianom w wyniku turbulencji atmosfery, pionowego gradientu temperatury, działania wiatru i opadu atmosferycznego.
3
Content available remote The waveform comparison of three fractional viscous acoustic wave equations
EN
The forward simulation of the viscous acoustic wave equation is essential for understanding wave propagation and seismic inversion. The viscous acoustic seismic wave equations are diverse, even if we limit the study scope to the fractional viscous wave equations. In present study, we consider three Riesz fractional viscous wave equations: the Fractional Viscous Acoustic Wave (FVAW) equation, Dispersion-Dominated Wave (DDW) equation, and Attenuation-Dominated Wave (ADW) equation. The Acoustic Wave (AW) equation, as a special fractional wave equation, is used to compare with the three fractional viscous acoustic equations. The Asymptotic Local Finite Difference (ALFD) method is adopted to solve the fractional derivative term; while, the Lax-Wendroff Correction (LWC) scheme is used to solve the integer derivative term. The analysis results indicate that the numerical scheme of the ADW equation exhibits the most rigorous stability condition, and that of the DDW equation is the most flexible. When the product of complex wavenumber k and spatial step size h equal to π, the maximum phase velocity errors of the FVAW equation, DDW equation, ADW equation, and AW equation are 27.78%, 28.02%, 2.25%, and 3.04%, respectively. Numerical experiments demonstrate that the FVAW equation not only governs the arrival time but also influences the amplitude. The DDW equation governs the arrival time but not amplitude; while, the ADW equation controls the amplitude but not arrival time. As the quality factor Q decreases, the viscous features of these three wave equations become pronounced. The change of amplitude is more noticeable than that of arrival time, suggesting that arrival time is more robust than amplitude. Based on these findings, we suggest incorporating the step for selecting the governing equations when dealing with practical Full-Waveform Inversion, which is helpful to improve the accuracy and reliability of the inversion results. Our results not only emphasize the importance of understanding the behavior of viscous wave equations, but also provide waveform evidence for selecting seismic governing equations in Full-Waveform Inversion.
EN
This paper presents an algorithm for detecting wave packets in a circular waveguide. The waveguide terminated with a concrete plug was used to test the method. The concrete was made in accordance with the Eurocode standard. During the tests, a significant difference was observed between the behavior of the speaker and the concrete plug. The pulse reflected from the plug maintained its shape regardless of the sound level. The reflection of the pulse from the speaker's diaphragm resulted in a significant change in the form and duration of the wave packet. These changes were dependent on the sound level of the wave packet. As a result of these modifications was a significant difference between the measurement uncertainty of detecting a pulse reflected from the concrete and the speaker. In the case of reflection from the speaker, an uncertainty of 0.036% was obtained. The smallest measurement error value for the pulse reflected from the speaker was 2.5%.
EN
The study examined the influence of selected inorganic fillers (5 and 10% by mass) on the foaming process, physicochemical properties, and structure of self-extinguishing polyurethane foam (density of approx. 35 kg/m3) obtained by reacting polyol with isocyanate (100:110). The filler used was bentonite (B), lamellar graphite (G), dendritic copper (Cu), aluminum oxide (Al2O3) and silicon carbide (SiC) and Al2O3/SiC mixture (1:1). Stereoscopic microscopy was used to determine the structure. The functional properties were examined based on density, water absorption and fire resistance. The course of the foaming reaction depends on the content, type and physicochemical properties of the filler. The addition of bentonite increases water absorption and Al2O3 reduces flammability of the foam.
PL
W pracy zbadano wpływ wybranych napełniaczy nieorganicznych (5 i 10 % mas.) na proces spieniania, właściwości fizykochemiczne i strukturę samogasnącej pianki poliuretanowej (gęstość ok. 35 kg/m3), którą otrzymano w wyniku reakcji poliolu z izocyjanianem (100:110). Jako napełniacza użyto bentonitu (B), grafitu o budowie lamelarnej (G), miedzi o strukturze dendrytycznej (Cu), tlenku glinu (Al2O3) i węglika krzemu (SiC) oraz mieszaninę Al2O3/SiC (1:1). Do oceny struktury stosowano mikroskopię stereoskopową. Właściwości użytkowe oceniano na podstawie gęstości, absorpcji wody i odporności na ogień. Przebieg reakcji spieniania zależy od zawartości, rodzaju i właściwości fizykochemicznych napełniacza. Dodatek bentonitu zwiększa absorpcję wody, a Al2O3 zmniejsza palność pianki.
EN
The article presents the use of mathematical statistics to determine controllable factors that influence the coefficient of friction in a dual-flow three-stage spur gear transmission of a newly designed sucker rod pumping unit. The load acting on the bearing units, the rotational speed of the main and auxiliary shafts, and the diametrical gap between the shaft and the bushing were assessed through tests. The tests were carried out in random order. The multivariate testing was used to determine the number of tests to be performed as well as the test conditions in order to achieve the required accuracy bushing. In the statistical analysis of the results, the Cochrane criterion was applied to verify the homogeneity of the variance values. Student's t-test was used to verify the significance of the coefficients included in the regression equation, Fisher’s F-test was used to determine the suitability of the adopted output function for describing the real object of study, i.e., the adequacy of the model, and sensitivity coefficients were used to assess the influence of the corresponding parameters on the optimization parameter. The analysis also considered the dispersion of optimization parameters, measurement repeatability, and errors in the model coefficients. Experimental values of the criteria, along with the dispersion of the adequacy and repeatability of the mathematical model, were evaluated to determine whether the model is fully suitable for the object of study. The impact of significant factors and their combinations, as well as their critical values, were assessed by comparing calculated values of the criteria. The significance or insignificance of the corresponding coefficients of the regression equation was determined. To investigate the impact of these controlled factors — load, rotational speed of the main and auxiliary shafts, and the diametrical gap between the auxiliary shaft and the bushing — on the sliding friction coefficient, a modernized device was developed. This device simulates the operating conditions of a double friction sliding bearing in a dual-flow, three-stage spur gearbox bushing. The experiments were conducted using I-40A industrial oil at room temperature. It has been determined that these factors significantly impact the coefficient of friction in a double friction bearing. Consequently, it is necessary to calculate their limit values to ensure the bearing assembly operates without failure during the required service life. Compared to other examined parameters, the optimization parameter, i.e., the coefficient of friction, is most significantly influenced by the diametrical gap between the auxiliary shaft and the bushing, and least affected by the magnitude of the load acting on the bearing assembly. The overall impact of controlled factors on the coefficient of friction is minimal. Employing the test planning method, a mathematical formula was derived, enabling the determination of the coefficient of friction in a double sliding friction bearing without additional tests within the range of limit bushing values of contact parameters.
PL
W artykule przedstawiono zastosowanie statystyki matematycznej do określenia sterowalnych czynników wpływających na współczynnik tarcia w podwójnej, trójstopniowej przekładni zębatej czołowej nowo zaprojektowanej pompy żerdziowej. Za pomocą badań oceniono obciążenie działające na zespoły łożyskowe, prędkość obrotową wału głównego i pomocniczego oraz średnicę szczeliny między wałem a tuleją. Badania przeprowadzono w losowej kolejności. Badania wielowariantowe wykorzystano do określenia liczby badań, które należy wykonać, a także warunków badawczych w celu osiągnięcia wymaganej dokładności. W analizie statystycznej wyników zastosowano kryterium Cochrane'a w celu weryfikacji jednorodności wartości wariancji. Test t-Studenta posłużył do weryfikacji istotności współczynników zawartych w równaniu regresji, test F-Fishera wykorzystano do określenia przydatności przyjętej funkcji wyjściowej do opisania rzeczywistego obiektu badań, tj. adekwatności modelu, a współczynniki wrażliwości wykorzystano do oceny wpływu odpowiednich parametrów na parametr optymalizacyjny. W analizie uwzględniono również rozrzut parametrów optymalizacyjnych, powtarzalność pomiarów oraz błędy we współczynnikach modelu. Eksperymentalne wartości kryteriów, wraz z rozproszeniem adekwatności i powtarzalności modelu matematycznego, zostały ocenione w celu ustalenia czy model w pełni spełnia wymagania stawiane obiektowi badań. Wpływ istotnych czynników i ich kombinacji, a także ich wartości krytyczne, oceniono poprzez porównanie obliczonych wartości kryteriów. Określono istotność lub nieistotność odpowiednich współczynników równania regresji. W celu zbadania wpływu tych kontrolowanych czynników – obciążenia, prędkości obrotowej wału głównego i pomocniczego oraz szczeliny średnicowej pomiędzy wałem pomocniczym a tuleją – na współczynnik tarcia ślizgowego, opracowano zmodernizowane urządzenie. Urządzenie to symuluje warunki pracy podwójnego łożyska ślizgowego w podwójnej, trzystopniowej przekładni czołowej. Eksperymenty przeprowadzono przy użyciu oleju przemysłowego I-40A w temperaturze pokojowej. Ustalono, że czynniki te mają znaczący wpływ na współczynnik tarcia w podwójnym łożysku ślizgowym. W związku z tym konieczne jest obliczenie ich wartości granicznych, aby zapewnić bezawaryjną pracę zespołu łożyskowego w wymaganym okresie eksploatacji. W porównaniu z innymi badanymi parametrami, na parametr optymalizacyjny, tj. współczynnik tarcia, największy wpływ ma szczelina średnicowa między wałem pomocniczym a tuleją, a najmniejszy wpływ ma wielkość obciążenia działającego na zespół łożysk. Ogólny wpływ kontrolowanych czynników na współczynnik tarcia jest minimalny. Wykorzystując metodę planowania badań, wyprowadzono wzór matematyczny umożliwiający wyznaczenie współczynnika tarcia w podwójnym ślizgowym łożysku bez dodatkowych badań w zakresie granicznych wartości parametrów styku.
7
Content available Dispersion of Methane in Closed Enclosures
EN
The increase of the population also involve the increase of the consumption of raw materials. This requires the diversification and development of industrial processes in semi-enclosed or open spaces. The carrying out of human activities of an industrial nature involves the accidental use, handling or presence of explosive substances such as methane. The presence of this gas in closed or semi-closed spaces can generate explosion phenomena. The accumulation of methane in narrow spaces is well studied and known, but the dispersion and especially the dispersion dynamics of methane released from a source considered infinite is less known. Knowing how methane disperses into the air is very important for establishing preventive measures. The paper presents the experiment on the dynamics of methane dispersion in a closed enclosure.
EN
The most important factor for the success of a company in today’s competitive environment is to have clearly defined goals. Objectives define what a company strives for, what it wants to achieve, and what it wants to realize in its activities. Clearly defined goals are necessary to ensure the sustainability and effectiveness of a company’s operations and the successful achievement of its desired results. This paper proposes an expert method for determining the strategic goals of a company. The experts ranked 24 strategic goals in terms of importance, and variance and coefficient of variation were then used to determine the consistency of the experts. As a result, 15 important strategic goals were identified of the 24 goals of the assessed transport company.
EN
Carbon nanotubes (CNT) and ethanol-assisted mixing were used to obtain composites based on a mixture of natural rubber and butadiene rubber (NR/BR 80/20). The structure of the composites was determined by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Thermal aging tests were also carried out and the vulcanization process was characterized. SEM confirmed the homogeneous dispersion of CNTs in the polymer matrix. Improvements in tensile and tear strength as well as thermal stability were also achieved.
PL
Do otrzymywania kompozytów na bazie mieszaniny kauczuku naturalnego i butadienowego (NR/BR 80/20) zastosowano nanorurki węglowe (CNT) i mieszanie wspomagane etanolem. Strukturę kompozytów określono za pomocą spektroskopii w podczerwieni z transformacją Fouriera (FTIR) oraz skaningowej mikroskopii elektronowej (SEM). Przeprowadzono również badania starzenia termicznego oraz scharakteryzowano proces wulkanizacji. Metodą SEM potwierdzono jednorodną dyspersję CNT w osnowie polimerowej. Uzyskano również poprawę wytrzymałości na rozciąganie i rozdzieranie oraz stabilności termicznej.
EN
The effect of the mixing method (normal and ethanol-assisted) on selected properties of natural rubber with butadiene rubber blends (NR/BR 80/20) was investigated. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to evaluate the properties. In addition, the mechanical tensile properties, tear resistance and thermal aging, as well as vulcanization characteristic were determined. It was found that ethanol-assisted mixing can significantly improve the mechanical properties and thermal stability of the blends as a result of better dispersion of additives in the rubber matrix.
PL
Zbadano wpływ metody mieszania (tradycyjna i wspomagana etanolem) na wybrane właściwości mieszanin kauczuku naturalnego z kauczukiem butadienowym (NR/BR 80/20). Do oceny właściwości zastosowano skaningową mikroskopię elektronową (SEM), spektroskopię w podczerwieni z transformacją Fouriera (FTIR) oraz analizę termograwimetryczną (TGA). Ponadto oznaczono właściwości mechaniczne przy rozciąganiu, odporność na rozdzieranie i starzenie termiczne, a także właściwości wulkanizacyjne. Stwierdzono, że mieszanie wspomagane etanolem może znacząco poprawić właściwości mechaniczne i stabilność termiczną mieszanin NR/BR, jako efekt lepszej dyspersji dodatków w osnowie gumowej.
EN
Myanmar represents an evolving continent of two crustal formation histories consisting of the Burma plate and the Indochina plate. The Burma plate (western part of Myanmar) consists of three distinct lithotectonic entities: 1) a continental fragment, 2) a subduction-related accreted complex (NeoTethys suture zone) in the westernmost part of Myanmar and 3) a coastal area. Eastern Myanmar that is western continuation of Indochina plate is composed of three tectonostratigraphic terranes: 1) Shan boundary belt (Meso-Tethys suture zone) in the western edge of Indochina plate, 2) Sibumasu terrane, 3) the Than Lwin Belt (Paleo-Tethys suture zone) in the easternmost part of Myanmar. The Than Lwin Belt is a tectonic linkage between Inthanon Zone of West Thailand in the south and Changning-Menglian belt of West Yunnan in the north (Aung, 2009). Shan Boundary Belt of Meso-Tethys suture in the western edge of Indochina plate extend to the south to Malay Peninsula. The Rakhine Western Ranges of Neo-Tethys suture at the westernmost part of Myanmar is a northern continuation of Andaman-Nicobar belt. Story of the Tethys is the story of extinctions of sea and telling that story was learned from clues in rocks and fossils. Biostratigraphic correlation between the known distribution of dominant Mesozoic representatives of Monotis, Halobia, and Daonella fauna and microfossil assemblages of Triassic age from Myanmar are made with those from neighboring countries of SE Asia for reconstruction of tectonic terranes for Myanmar. The terranes in Myanmar may have originated in Gondwana in Paleozoic (Figs 1, 2). The accretionary episodes which ended in early Tertiary, have been followed by post-accretionary deformation of strike- slip faulting of the Sagaing Fault in Myanmar; West Andaman Fault and Sumatra Fault System in Sumatra; and spreading in Andaman backarc basin. To reconstruct the palaeogeography of Myanmar terranes distribution of Mesozoic representatives of Monotis, Halobia, and Daonella faunas and Tethyan fusulinids are used. Various species of thin-shelled pectinacid bivalves of Triassic faunas are dominant family and occur in open-marine strata of allochthonous accretionary terranes. These strata are related to different parts of single ocean: Tethys, palaeoequatorial ocean populated by these faunas containing Tethyan fusulinids. Their occurrences in mudstones, sandstones, shale and limestone are very important for Triassic sedimentary succession as diagnostic fossils. Distribution of these faunas and biogeographic studies are an importance in reconstructing post-Triassic intraoceanic plate boundaries and motion. Distribution of these faunas in Triassic marine strata of Shan Massif and correlation with those of neighboring terranes of Asia gave the evidences that Shan Massif was a part of Gondwana in Carboniferous-Permian time facing Paleo-Tethys Ocean. Shan Massif probably separated from Gondwana in Early Triassic time and moved northward from equatorial position. Ophiolites thrusted onto Mesozoic sequences of Halobia shales in pre-Middle Eocene (Rangin, 1996–1999). Their position above the metasedimentary rocks is similar to the Halobia shales of Sumatra which also lies on top of metasedimentary rocks of Permo-Carboniferous Sequences (Bender, 1983). All the Tertiary sequences of Central Myanmar Basin are considered to be deposited on the underlying Burma plate as basement. Initial collision between India and Burma plate in middle Eocene (45–35-Ma) and hard collision during Oligocene to Miocene (23 Ma) and Rakhine Western Ranges became uplifted during Middle Miocene to Late Miocene (Curray, 2005) by thrusting the remnants of NeoTethys sea floor and trench deposits to become Rakhine accretionnary wedge and ophiolites belt at the western part of Burma plate.
EN
The main idea of the measurement presented in this paper was to separate the incident wave from the reflected wave. For this purpose, short wave packets and a sufficiently long waveguide with a circular cross-section were used. Several types of wave packets were developed and used in the experiment. We found that a wave packet of 5 ms duration could be propagated in a waveguide of length 5.6 meters without significant sound level losses. We used an audio interface operating at a sampling rate of 96 kHz in the measurements. The limit of wave propagation without dispersion phenomenon was determined. The developed measurement methodology made it possible to maintain the same air temperature along the entire length of the tested waveguide since short pulses did not cause the speaker temperature to rise. Avoiding this effect reduced the measurement uncertainty of the reflection coefficient.
EN
Purpose: The aim of the presented work was to develop an economical, transparent coating with dispersed TiO2 dispersion and inorganic polysiloxane resin for glass windows application and to study its effectiveness in filtering IR and UV radiations. Design/methodology/approach: Two oligomeric silanes were prepared in different molar ratios to produce inorganic polysiloxane resin. They were tested for their viscosity to reflect the completion of the reaction and form an amide linkage. FTIR was done to support the viscosity result by proving the presence of amide linkages. 10%, 20%, and 30% of compounded TiO2 were successfully dispersed in 0.3% sodium sulfosalicylate (dehydrated ethanol). Each TiO2 concentration was characterized for size distribution and polydispersity index (PDI). Additives solutions of 2-hydroxybenzophenone (HBP) and boron trifluoride (BF3) were also soluted in the same solvent. Glass substrates were coated with the formulations and tested for curing and hardness properties. Windows Energy Profiler (WEP) was used to study the UV, IR, and daylight transmission of the coated glasses. Findings: Each inorganic polysiloxane resin showed various viscosity values before reaching a constant state which designates complete formations of amide linkages. Polysiloxane resin with a viscosity value of 30.5 mPa/s was the most ideal to act as a binder. FTIR characterization proved the formation of amide linkages. The particle size distribution of TiO2 recorded the size of 87 nm after dispersion with correlating value of 1 PDI. The fastest drying time of 3 hours was recorded. The pencil hardness test quoted 6H pencil as the hardest pencil grade. WEP analysis of UV, IR, and daylight transmission gives satisfactory results of 0%, 7%, and 61%, respectively. Research limitations/implications: Laboratory analysis for viscosity tests often being held off. The test requires the samples to be transferred in a cylinder with an open-air spindle rotation. Samples react with the surrounding environment. Thus, polymerization takes place rapidly, resulting in hardened samples inside the cylinder. The different measure was taken by wrapping the testing area with aluminium foil. This research was conducted under equatorial climate. Practical implications: The obtained test results may contribute to the conclusion of transparent TiO2 nano-particles coating on glass substrates for windows application. This can reduce the electricity usage in buildings for artificial cooling to provide indoor thermal comfort. Smart coating formulations have a noticeable effect on filtering harmful solar radiation. Originality/value: This study presents the economical and undemanding ways to develop transparent smart coating formulation with superior performance against solar radiation. It is expected to have a bright potential in the architectural industry.
EN
The work describes the methodology and results of analysis for the consequences assessment of eruption from Cumbre Vieja volcano in Canary Islands. The preliminary analysis of dispersion of emitted pollutants was performed using Lagrangian trajectories model. To estimate long-term outcomes of eruption in terms of deposition and concentration of eruption products the Eulerian model of air dispersion was used. The model uses data from Global Forecasting System meteorological model launched at the NCEP-NOAA centre. The average concentration and deposition of sulfur compounds as well as the probability and time of the pollution cloud reaching all European capitals were examined. In 90 days a cloud of pollutants (SO2, volcanic ashes) spread over the northern hemisphere. Pollution reached Africa, North Sea and Europe. With an average emission of 15,000 tons of SO2/day, the maximum calculated deposition to the Earth’s surface reached 0.8g/m2, while overall deposition – 35 kilotons in the domain area.
PL
W pracy opisano metodykę i wyniki oceny skutków erupcji wulkanu Cumbre Vieja na Wyspach Kanaryjskich. Wstępną analizę dyspersji emitowanych zanieczyszczeń przeprowadzono z wykorzystaniem modelu trajektorii Lagrange’a. Do oszacowania długoterminowych skutków erupcji pod względem osadzania i koncentracji produktów erupcji wykorzystano eulerowski model dyspersji powietrza. W modelu wykorzystano dane z modelu meteorologicznego Global Forecasting System uruchomianego w ośrodku NCEP-NOAA. Zbadano średnie stężenie i depozycję związków siarki oraz prawdopodobieństwo i czas dotarcia chmury zanieczyszczeń do wszystkich stolic europejskich. W ciągu 90 dni chmura zanieczyszczeń (dwutlenek siarki, popioły wulkaniczne) rozprzestrzeniła się na półkuli północnej. Zanieczyszczenia dotarły do Afryki, Morza Północnego i Europy. Przy średniej emisji 15 000 ton dwutlenku siarki na dobę maksymalna wyliczona depozycja na powierzchni Ziemi osiągnęła 0,8 g na metr kwadratowy, a ogólna depozycja 35 kiloton w obszarze domeny.
15
Content available remote Deep-neural-networks-based approaches for Biot-squirt model in rock physics
EN
A new cost-effective surrogate model using deep neural network (DNN) for seismic wave propagation in rocks saturated with fluid is presented. In this field, the dispersion/attenuation analysis and wave-field simulation are two key measurements which can be carried out by solving wave equations. The Biot–squirt (BISQ) equation is a classical wave propagation model in geophysical forward modeling and has been widely used. The solution of such equation, especially by numerical method, is often complex and time-consuming. In this work, a DNN model is trained with the dataset of velocity and inverse quality factor generated from BISQ model. The results show that the relative mean square error between the predictions of DNN model and that of BISQ model on the test sets are all less than 3%. It indicates that the DNN model has learned the high-dimensional space well and then can realize the dispersion/attenuation analysis for any given rock physical parameters. Besides, the other well-trained DNN model is used to obtain the simulation results with second-order accuracy according to results by finite difference scheme with first-order accuracy. It reveals that the fast wave-field simulation can be implemented once the results with lower accuracy are obtained.
EN
Demonstrating the impact of time-dependent ground adsorption capacity on the change in chemical composition of groundwater is an important issue in understanding the groundwater mass transport process. Commonly used parameters characterizing ground adsorption capacity (Ra, ux* = ux/Ra, Δ C*max) were analyzed in this work to demonstrate time-varying values of this capacity for a chosen type of ground. Analysis of values of the selected parameters showed a gradual time decline in ground adsorption capacity as well as a gradual increase of groundwater contamination. This gradual increase in groundwater contamination over time is also important in practice. It implies the necessity to use more and more advanced (expensive) methods of water treatment in groundwater intakes.
PL
Wykazanie wpływu zależnej od czasu pojemności adsorpcyjnej gruntu na zmianę składu chemicznego wód podziemnych jest ważnym zagadnieniem w zrozumieniu procesu transportu masy wód podziemnych. W niniejszej pracy przeanalizowano powszechnie stosowane parametry charakteryzujące pojemność adsorpcyjną gruntu (Ra, ux* = ux/Ra, Δ C*max ), aby wykazać zmienne w czasie wartości tej pojemności. Dokładna analiza wartości liczbowych wybranych parametrów wykazała spadkową w czasie tendencję pojemności adsorpcyjnej gruntu, a także stopniowy wzrost zanieczyszczenia wód gruntowych. Ten stopniowy w czasie wzrost zanieczyszczenia wód gruntowych jest również ważny w praktyce. Wiąże się bowiem z koniecznością stosowania coraz bardziej zaawansowanych (kosztownych) metod uzdatniania wód podziemnych pobieranych z ujęć.
EN
Intensive studies have been conducted on fuid-related seismic dispersion and attenuation in saturated anisotropic media. Most of the studies are concentrated on the transversely isotropy media. However, the fractures distribution in subsurface reservoirs is often complex. When there are multiple fracture sets developing in a porous background, the signatures of seismic dispersion and attenuation remain unclear. In this paper, we propose a method to calculate the frequency-dependent stifness matrix of a porous medium with multiple fractures sets from a perspective of viscoelasticity. Due to the favorable approximation performance of the generalized standard linear solid model and Chapman model, we use a modifed form of generalized standard linear solid model to simulate the frequency-dependent stifness tensor of porous media with multiple fracture sets. The representation of the stifness tensor utilizes the modulus defect to denote the efects the fractures including fracture density and geometry. With the procedure of calculating the stifness tensors at low- and high-frequency limits, we can easily calculate the frequency-dependent stifness tensor for media with multiple fracture sets with arbitrary orientations and directions. We then analyze the efects of the fracture parameters on the viscoelasticity characteristics taking orthotropic medium as an example. The results can help to understand the viscoelasticity and the mesoscopic seismic attenuation associated with fractures and fuids and can provide a practical rock physics model when dealing with reservoirs with complex fracture patterns.
PL
Przedstawiono wyniki badań stabilności wodnych dyspersji akrylowych z dodatkiem azotanu(V) benzalkoniowego, środka powierzchniowo czynnego (SPC) i zagęszczaczy. Zbadano właściwości fizykomechaniczne powłok ochronnych otrzymanych z tych dyspersji. Spośród analizowanych dyspersji najstabilniejsze układy i powłoki o dobrych właściwościach ochronnych uzyskano przy zastosowaniu 1% mas. cieczy jonowej, 5% SPC i zagęszczacza poliuretanowego DSX 1514.
EN
A com. available acrylic dispersion was modified by addn. of an ionic liq. (benzalkonium nitrate), a surfactant (ethoxylated lauryl alcohol) and a polyurethane thickener. The stability, surface tension and viscosity of the dispersions obtained, as well as the phys.-mech. properties of the coatings obtained from them (thickness, gloss, adhesion, impact resistance, resistance to tearing and compression test) were detd. The most stable systems and coating with good protective properties were obtained for dispersions containing the ionic liq., surfactant and the polyurethane thickener in amts. of 1, 5 and 0.3 % by mass, resp.
EN
In this paper, the dispersion of a solute in the peristaltic propulsion of an incompressible and viscous fluid through a permeable medium under the influence of wall properties with simultaneous homogeneous, heterogeneous chemical reactions in an inclined uniform channel has been studied. The issue is studied through conditions of Taylor’s limit and long wavelength hypothesis. The mean effective coefficient of scattering expression is computed and outcomes are interpreted physically through graphs.
PL
Ważnym zagadnieniem w transporcie zanieczyszczeń w gruncie jest wykazanie wpływu zależnej od czasu pojemności adsorpcyjnej tego gruntu na zmianę jakości wód podziemnych (w strefie saturacji). W pracy, dla wybranego gruntu i przepływających w nim zanieczyszczeń, wykazano tendencję zmiany pojemności adsorpcyjnej tego gruntu na podstawie wybranych parametrów charakteryzujących tę pojemność (Ra, ux/Ra, ΔC*max). Analiza liczbowych wartości tych parametrów wykazała zarówno spadkową w czasie tendencję pojemności adsorpcyjnej analizowanego gruntu jak i stopniowy wzrost zanieczyszczenia wód gruntowych. Dlatego wnioski wynikające z tych badań mogą być bardzo użyteczne w praktyce, gdy wykorzystuje się zasoby tych wód do różnych celów i gdy jednocześnie czystość tych wód maleje w czasie.
EN
An important issue in the transport of pollutants in the ground is the demonstration of the impact the time-dependent adsorption capacity of this ground on the change in the quality of groundwater (in a saturated zone). At work both for the selected ground and pollutants flowing in it, there is a tendency change of the adsorption capacity of this ground based on the adopted parameters characterizing this capacity (Ra, ux/Ra, ΔC*max). The analysis of the numerical values of these parameters showed both a declining tendency in time of the adsorption capacity of the analyzed ground as well as in a gradual increase contamination of groundwater. Therefore, the conclusions of these research can be very useful in practice, when using groundwater resources for various purposes and when simultaneously the purity of these waters decreases in time.
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