Temat: natural liquid - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Studies of resistances of natural liquid flow in helical and curved pipes
Autorzy:: Stosiak, M.
Zawiślak, M.
Nishta, B.
Tematy:: flow
resistance of flow
helical pipe
curved pipe
natural liquid
laminar flow; Pokaż więcej
Wydawca:: Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Powiązania:: https://bibliotekanauki.pl/articles/258608.pdf Link otwiera się w nowym oknie
Opis:: The main aim of this research was to determine in three ways, i.e. experimentally, analytically and by means of numerical modelling, the resistances of the flow of a natural liquid in a helical pipe and in curved pipes. The analyses were carried out for three pipes: one helical pipe and two curved pipes. Each of the pipes was 2 m long and its inside diameter was 4 mm. The experiment was carried out on a test stand making it possible to measure the rate of the flow of the liquid, the temperature at the pipe’s inlet and outlet and the pressure at the pipe’s inlet and outlet. The resistances of the flow of the liquid were calculated from analytical or empirical formulas found in the literature on the subject. Moreover, numerical modelling was performed using the finite volume element method.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 2.

Tytuł:: Modeling the location and routing problem for the distribution of liquefied natural gas
Autorzy:: Chłopińska, Ewelina
Gucma, Maciej
Tematy:: liquid natural gas
distribution
routing; Pokaż więcej
Wydawca:: Polskie Forum Nawigacyjne
Powiązania:: https://bibliotekanauki.pl/articles/320657.pdf Link otwiera się w nowym oknie
Opis:: Programming methods, such as dynamic heuristic search or search and limit techniques are used for solving the problems of routing. Many of the problems to be solved require huge computing effort, some of them are NP-hard. Other optimization algorithms that may be used for solving vehicle routing problems are methods based on genetic algorithms, neural networks and ant algorithms. The problem of LNG distribution system is closely related to the problem of route planning. These problems are characterised by a simple definition of the problem, unlike finding the solution. Finding the optimal outcome for a great number of points is a hard and work-consuming task. Genetic algorithms are an alternative for the methods most often used so far.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 3.

Tytuł:: Impact of raw liquid natural gas composition on combustion properties and emission characteristic
Autorzy:: Czyżewski, Paweł
Ślefarski, Rafał
Jójka, Joanna
Tematy:: toxic compounds
fuel flexibility
liquid natural gas
NO emission; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/2204069.pdf Link otwiera się w nowym oknie
Opis:: The article presents the results of numerical and analytical investigations of the influence of raw liquid natural gas (LNG) composition on parameters characterizing the combustion process. The high content of higher hydrocarbons influences the thermodynamic combustion process described with parameters like the adiabatic flame temperature, laminar flame speed and ignition delay time. A numerical study of the impact of LNG fuels on emission characteristics using the Cantera code has been performed. Results have shown that the change of grid natural gas to some types of liquid natural gas can result in an incomplete combustion process and an increase of emission of toxic compounds such as carbon monoxide and unburned hydrocarbons. For all investigated fuels the laminar flame speed rises by about 10% compared to natural gas, while the adiabatic flame temperature is nearly the same. The ignition delay time is decreased with an increase of ethane share in the fuel. The analysis of chemical pathways has shown that hydrogen cyanide and hydrogen formation is present, particularly in the high temperature combustion regimes, which results in an increase of nitric oxide molar fraction in flue gases by even 10% compared to natural gas. To summarize, for some applications, liquid natural gases cannot be directly used as interchangeable fuels in an industry sector, even if they meet the legal requirements.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 4.

Tytuł:: Aspects of using LNG as a marine fuel
Autorzy:: Herdzik, J.
Tematy:: marine fuel
ships propulsion
LNG
liquid natural gas
atmosphere protection; Pokaż więcej
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Powiązania:: https://bibliotekanauki.pl/articles/247852.pdf Link otwiera się w nowym oknie
Opis:: The paper presents a probe of LNG usage analysis as a marine fuel. The restrictions of harmful substances emission to atmosphere from marine engines, especially in controlled emission areas (ECA and SECA areas) of nitrogen oxides and sulfur oxides, forces the engine makers to use additional installations, which operation may fulfill the cleanness requirements of exhaust gases. The option is a usage such marine fuels which fulfill the requirements without any cleaning processes. Such fuels are gaseous fuels, especially liquid natural gas (LNG) or compressed natural gas (CNG). It was undertaken many tests for determination the conditions of safety bunkering, storage on board, preparation and supplying the fuel to the engine and realization of working process. About dozens merchant ships were applied LNG as a fuel. There is enough experience for spreading the LNG usage. The basic problem is still the limited network of LNG distribution in ports. The next one is the conviction of ship-owners that is no return from transition to the LNG or CNG fuelling. In the end it may occurred to the double beneficial situation that the fuel costs would be decreasing and simultaneously the improvement of exhaust gases quality (the restriction of negative effects for the natural environment).
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 5.

Tytuł:: Concentration of selected natural radionuclides in the thermal groundwater of Uniejów, Poland
Autorzy:: Bem, H.
Olszewski, M.
Kaczmarek, A.
Tematy:: natural radionuclides
alfa/beta liquid scintillation counting
thermal groundwater; Pokaż więcej
Wydawca:: Instytut Chemii i Techniki Jądrowej
Powiązania:: https://bibliotekanauki.pl/articles/147969.pdf Link otwiera się w nowym oknie
Opis:: Activities of the main radionuclides from the 238U and 232Th series in the Uniejów geothermal water were determined by combining liquid scintillation counting with a/b separation and g-spectrometry methods. The 222Rn and 226Ra activities were measured after extraction of radon from 10 ml water samples to 10 ml of an Ultima Gold F scintillation cocktail directly in 22 ml scintillation vials. The samples were counted in a new generation portable liquid scintillation counter, Betascout, without separation of the phases over the period of 30 days after extraction. The average values of the specific activities were equal to 2.95 and 0.64 Bq/dm3 for 222Rn and 226Ra, respectively. The 210Po radionuclide before counting was preconcentrated from 1 dm3 water samples on hydrated manganese oxide and deposited on silver discs. The discs were immersed in 10 ml of the scintillator and their activity was measured also by the same method. The average 210Po concentration was 0.052 Bq/dm3. Activity of the remaining radionuclides was determined by g-spectrometry after their preconcentration on hydrated manganese oxides from 10 dm3 samples. The activities of two radium radionuclides, 224Ra and 226Ra, can be calculated from their basic gamma-lines, whereas 228Ra can be determined from its decay product - 228Ac, and were equal to 0.40, 0.65 and 0.58 Bq/dm3, respectively. The activities of 210Pb and 238U (234Th) were below the detection limit of the method equal to 0.03 Bq/dm3. Based upon the obtained results, it can be concluded that there are not any radiological restrictions for using this water as a heat source or for balneological purposes. However, it cannot be used as drinking water, because the calculated committed effective dose from its one year consumption exceeds the WHO recommended value of 0.1 mSv.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 6.

Tytuł:: The research of anti corrosive properties of various compositions on samples of standard metals
Autorzy:: Aghazada, Y. J.
Abbasov, V. M.
Abdullayev, S. E.
Hasanov, E. K.
Suleymanova, S. S.
Tematy:: metalworking fluids and lubricants
corrosion
liquid rubber
natural petroleum acids; Pokaż więcej
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Powiązania:: https://bibliotekanauki.pl/articles/778505.pdf Link otwiera się w nowym oknie
Opis:: In this proceeding. the compositions of the T-30 turbine oil with liquid rubber. Co. Ni. Zn. Mg and Ba salts of the natural petroleum acids (NPA) boiling in the range 220–340°C and nitro compounds which are produced on the basis of C₁₄ H₂₈ α-olefins have been investigated in different ratio and contents as metalworking fluids (MWF). The physical and chemical properties of the produced compositions have been studied. and the morphology of inhibited carbon steel surface was analyzed and characterized by using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) techniques. The effect of the temperature on the inhibition efficiency and thermodynamic parameters have also been reported. The thermal analyzer was used for the thermogravimetric analysis (TG/DTA) of the prepared MWF. The experiments have been operated with different concentrations of the inhibitor on the steel plates in condensation and environment phases in the experiment chamber.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 7.

Tytuł:: Natural antioxidants in seeds of winter rapeseed (Brassica napus L.)
Naturalne antyoksydanty w oleju z nasion rzepaku ozimego
Autorzy:: Zukalova, H.
Vasak, J.
Tematy:: natural antioxidant
antioxidant
seed
winter rapeseed
rapeseed
Brassica napus
tocopherol
phenolic compound
separation
high performance liquid chromatography; Pokaż więcej
Wydawca:: Instytut Hodowli i Aklimatyzacji Roślin
Powiązania:: https://bibliotekanauki.pl/articles/832880.pdf Link otwiera się w nowym oknie
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 8.

Tytuł:: Managment of natural fertilizers in Poland
Gospodarowanie nawozami naturalnymi w Polsce
Autorzy:: Kopiński, J.
Wrzaszcz, W.
Tematy:: management
natural fertilizers
fertilized area
manure
liquid manure
slurry
gospodarowanie
nawozy naturalne
powierzchnia nawożona
obornik
gnojówka
gnojowica; Pokaż więcej
Wydawca:: The Polish Association of Agricultural and Agribusiness Economists
Powiązania:: https://bibliotekanauki.pl/articles/1790241.pdf Link otwiera się w nowym oknie
Opis:: The study discusses the results of the analysis of changes in the management of natural fertilizers in Poland and voivodships. Analysis included changes in: the number and percentage of individual farms using natural fertilizer, fertilized area, and level of consumption of particular fertilizer types. The comparative analysis at a voivodship level concerned the years 2007 and 2016. The current situation with regard to fertilized area and natural fertilizer rates was also assessed on the basis of Statistics Poland data from the years 2018-2019. The results of analyses indicated that the number of farms using natural fertilizers in Poland has clearly decreased. Despite observing an increase in the interest in slurry application, the most popular natural fertilizer applied is still manure, which, in the years 2018-2019, was applied on 18% of utilized agricultural area. In Poland, the average annual rates of applied manure, liquid manure and slurry are, respectively 17 t/ha, 22 m3/ha and 26 m3/ha. An analysis of the organization and intensity of natural fertiliser management in the Podlaskie Voivodeship shows that this is the leading region in this aspect, which confirms its dominant position in livestock production in Poland.
W artykule omówiono zmiany gospodarowania nawozami naturalnymi w Polsce i w poszczególnych województwach kraju. Analiza dotyczyła zmian liczby i udziału gospodarstw indywidualnych stosujących nawożenie naturalne, powierzchni nawożonej i poziomu zużycia poszczególnych rodzajów nawozów naturalnych. Analiza porównawcza na poziomie województw dotyczyła lat 2007 i 2016. Oceniono także aktualną sytuację w zakresie nawożonej powierzchni oraz dawek nawozów naturalnych na podstawie danych za lata 2018-2019. Na podstawie wyników analiz wykazano, że w Polsce wyraźnie zmniejszyła się liczba gospodarstw stosujących nawozy naturalne. Mimo wzrostu zainteresowania stosowaniem gnojowicy, nadal najbardziej popularnym nawozem naturalnym był obornik, który w latach 2018-2019 stosowano na 18% użytkowanej rolniczo powierzchni. W Polsce średnioroczne dawki stosowanego obornika, gnojówki i gnojowicy wynosiły odpowiednio: 17 t/ha, 22 m3/ha i 26 m3/ha. Z przeprowadzonej analizy organizacji i intensywności gospodarowania nawozami naturalnymi wynika, że najbardziej wiodącym pod tym względem było województwo podlaskie, co potwierdza jego dominującą pozycję w produkcji zwierzęcej w Polsce.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 9.

Tytuł:: Biomodifications of resveratrol by Phanerochaete chrysosporium
Autorzy:: Brzezinska-Rodak, M.
Lubiak, K.
Klimek-Ochab, M.
Majewska, P.
Zymanczyk-Duda, E.
Tematy:: resveratrol
biological modification
Phanerochaete chrysosporium
phenolic antioxidant
natural antioxidant
biotransformation
white-rot fungi
high performance liquid chromatography
methyltransferase activity; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/80963.pdf Link otwiera się w nowym oknie
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Skocz do pozycji: 10.

Tytuł:: Adsorption of natural surfactants present in sea waters at surfaces of minerals: contact angle measurements
Autorzy:: Mazurek, A.
Pogorzelski, S.J.
Boniewicz-Szmyt, K.
Tematy:: mineral
Baltic Sea
natural surfactant
solid-liquid interface
Gdansk Gulf
film pressure
contact angle hysteresis
film-covered surface
sea water
adsorption; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Powiązania:: https://bibliotekanauki.pl/articles/48416.pdf Link otwiera się w nowym oknie
Opis:: The wetting properties of solid mineral samples (by contact angles) in original surfactant-containing sea water (Gulf of Gdańsk,Ba ltic) were characterised under laboratory conditions on a large set (31 samples) of well-classified stones of diverse hydrophobicity using the sessile drop (ADSA-P approach),ca ptive bubble and inclined plate methods. An experimental relation between the static contact angle θeq and stone density ρ was obtained in the form θeq = Bρ + C,wher e B = 12.23 ± 0.92, C = −(19.17 ± 0.77),an d r2 = 0.92. The histogram of θeq distribution for polished stone plates exhibited a multimodal feature indicating that the most abundant solid materials (hydrophilic in nature) have contact angles θeq = 7.2,10. 7,15. 7 and 19.2◦,whic h appear to be applicable to unspecified field stones as well. The contact angle,a pH-dependent quantity,ap pears to be a sensitive measure of stone grain size,e.g . granite. The captive bubble method gives reproducible results in studies of porous and highly hydrophilic surfaces such as stones and wood. The authors consider the adsorption of natural sea water surfactants on stone surfaces to be the process responsible for contact angle hysteresis. In the model,an equation was derived for determining the solid surface free energy from the liquid’s surface tension γLV; it also enabled the advancing θA and receding θR contact angles of this liquid to be calculated. Measurements of contact angle hysteresis Δθ(= θA − θR) with surfactant-containing sea water and distilled water (reference) on the same stone surfaces allowed the film pressure ΔΠ (1.22 to 8.80 mJ m−2), solid surface free energy ΔγS (−17.03 to −23.61 mJ m−2) and work done by spreading ΔWS (−1.23 to −11.52 mJ m−2) to be determined. The variability in these parameters is attributed to autophobing,an effect operative on a solid surface covered with an adsorptive layer of surfactants. The wetting behaviour of solid particles is of great importance in numerous technological processes including froth flotation,d emulgation,an ti-foaming procedures and the coal industries. It is believed that the approach presented here and the examples of its application to common sea water/solid mineral systems could be successfully adapted to optimise several surfactant-mediated adsorption processes (see below) of practical value in natural water ecology.
Dostawca treści:: Biblioteka Nauki

Artykuł

na półce

Informacja

Wyszukujesz frazę "natural liquid" wg kryterium: Temat