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Tytuł:
Analytical method for determining antropometric parameters in body mass reduction process in the aspect of health safety
Analityczna metoda określania parametrów antropometrycznych w procesie redukcji masy ciała w aspekcie bezpieczeństwa zdrowia
Autorzy:
Ślęzak, A.
Ślęzak-Prochazka, I.
Batko, K. M.
Zyska, A.
Gawrys, W.
Jóźwiak, J.
Powiązania:
https://bibliotekanauki.pl/articles/103598.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Humanistyczno-Przyrodniczy im. Jana Długosza w Częstochowie. Wydawnictwo Uczelniane
Tematy:
overweight reduction
mathematical model
bioelectric impendance method
overweight reduction coefficient
low-sugar diet
health security
redukcja nadwagi
model matematyczny
metoda impedancji bioelektrycznej
współczynniki redukcji nadwagi
dieta niskocukrowa
bezpieczeństwo zdrowotne
Opis:
In this study, for the first time we developed a mathematical model showing that the reduction in parameters such as total body mass, total fat mass, visceral fat mass, waist circumference, hip circumference and body mass index (BMI) can be described using exponential equations. Constants kt, kf, kfv, kBMI, kp, kb that occur in particular equations characterize individual features related to these anthropometric parameters. The presented model was verified using experimental data obtained by analysis of body composition. These individuals were overweight in the initial moment of the experiment and eliminated or limited easily digestible products containing sugar from their diet. We showed that there is a critical time, when each individual achieved normal values of body mass index, fat mass, visceral fat mass, waist circumference, hip circumference, and waist-hip ratio. This critical time ranged between 35 and 46 weeks.
W tym badaniu jako pierwsi opracowaliśmy model matematyczny pokazujący, że zmniejszenie parametrów, takich jak całkowita masa ciała, całkowita masa tłuszczu, trzewna masa tłuszczowa, obwód talii, obwód bioder i wskaźnik masy ciała (BMI), można opisać za pomocą równania wykładniczego. Stałe kt, kf, kfv, kBMI, kp, kb występujące w poszczególnych równaniach charakteryzują poszczególne cechy związane z tymi parametrami antropometrycznymi. Przedstawiony model zweryfikowano za pomocą danych eksperymentalnych uzyskanych poprzez analizę składu ciała. Osoby badane miały nadwagę w początkowym momencie eksperymentu i wyeliminowały lub ograniczyły z diety łatwo przyswajalne produkty zawierające cukier. Pokazaliśmy krytyczny czas, kiedy każdy człowiek osiąga normalne wartości wskaźnika masy ciała, masy tłuszczu, masy trzewnej, obwodu talii, obwodu bioder i stosunku talii do bioder. Ten krytyczny czas waha się od 35 do 46 tygodni.
Źródło:
Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Technika, Informatyka, Inżynieria Bezpieczeństwa; 2017, T. 5; 191-208
2300-5343
Pojawia się w:
Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Technika, Informatyka, Inżynieria Bezpieczeństwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie wpływu podciśnienia w formie na chropowatość powierzchni odlewów
Studies of the effect of negative pressure in the mould on the cast surface roughness
Autorzy:
Łągiewka, M.
Konopka, Z.
Zyska, A.
Powiązania:
https://bibliotekanauki.pl/articles/391577.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Odlewnictwa
Tematy:
odlewanie ciśnieniowe
stopy aluminium
chropowatość powierzchni
pressure casting
aluminium alloys
surface roughness
Opis:
W artykule przedstawiono wyniki badań wpływu podciśnienia w formie i układzie zalewania na chropowatość powierzchni odlewów. Badania chropowatości powierzchni wykonano na odlewach ze stopu EN AB 46000 wykonanych metodą odlewania ciśnieniowego na maszynie Vertacast z zastosowaniem zmiennego podciśnienia w formie. Stwierdzono zmniejszenie chropowatości powierzchni odlewów ze zmniejszeniem ciśnienia w formie na podstawie wartości różnych charakterystycznych parametrów chropowatości. Badania chropowatości odlewów wykonano na urządzeniu Hommel Tester T1000.
The article discusses the results of the studies of the effect of negative pressure in the mould and the casting system on the roughness of the casts' surfaces. Roughness tests were performed on casts made of alloy EN AB 46000, by means of the pressure casting method in the Vertacast machine, and with the use of varying negative pressure in the mould. The surface roughness of the casts decreasing with a decrease in the pressure in the mould was determined based on the values of different characteristic surface roughness parameters. The cast roughness examinations were conducted on the Hommel Tester T1000 device.
Źródło:
Prace Instytutu Odlewnictwa; 2018, 58, 1; 3-11
1899-2439
Pojawia się w:
Prace Instytutu Odlewnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Castability and Structure of Dental Alloys on a Nickel Base
Autorzy:
Zyska, A.
Konopka, Z.
Łągiewka, M.
Kordas, P.
Powiązania:
https://bibliotekanauki.pl/articles/382918.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
dental alloys
centrifugal casting
castability
nickel alloys
stopy dentystyczne
odlewanie odśrodkowe
lojalność
stopy niklu
Opis:
The results of castability and structures researches of two nickel base alloys - Ceranium CN and Magnum AN applied on casting of the crowns and dental bridges are presented. Studies were carried out on the alloys cast under the centrifugal force to the moulds made by the lost wax method using production line of ROKO. Having regard to a specific technology of casting and possibility of ROKO production line, to the estimation of alloys castability a spiral test was adjusted with a 0,8 mm and a 2,5 mm diameter of test casting. Measuriements executed on a 20 test castings allowed to establish, that castability of Magnum AN alloy was 65 % greater than castability of Ceranium NC alloy. The results of thermodynamics calculations of the equilibrium and nonequilibrium crystallization (Scheil model) of the investigated alloys are presented too. The characteristic temperatures of phase transformation and forecast phase composition of alloys for both kind of crystallization were calculated. It is established after structural supervisions, that the investigated alloys crystallize in dendryte form and in centrifugal casting conditions have cooling rate sensivity and inclination to texture structure forming in outmost layer of casting. Phase composition of alloys corresponds to the results of thermodynamics calculations of the nonequilibrium crystallization conditions.
Źródło:
Archives of Foundry Engineering; 2018, 18, 1; 139-144
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Correlations Between Arrangement of Reinforcing Particles and Mechanical Properties in Pressure Die Cast AlSi11-SiC Composites
Autorzy:
Konopka, Z.
Pasieka, A.
Łągiewka, M.
Nadolski, M.
Zyska, A.
Powiązania:
https://bibliotekanauki.pl/articles/380134.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
pressure die casting
metal matrix composites (MMCs)
aluminium alloys
structure
mechanical properties
odlewnictwo ciśnieniowe
kompozyty metalowe (MMC)
stopy aluminium
struktura
właściwości mechaniczne
Opis:
The work presents the investigation results concerning the structure of composite pressure die castings with AlSi11 alloy matrix reinforced with SiC particles. Examination has been held for composites containing 10 and 20 volume percent of SiC particles. The arrangement of the reinforcing particles within the matrix has been qualitatively assessed in specimens cut out of the castings. The index of distribution was determined on the basis of particle count in elementary measuring fields. The tensile strength, the yield point and elongation of the obtained composite were measured. Composite castings were produced at various values of the piston velocity in the second stage of injection, diverse intensification pressure values, and various injection gate width values. The regression equation describing the change of the considered arrangement particles index and mechanical properties were found as a function of the pressure die casting parameters. The infuence of particle arrangement in composite matrix on mechanical properties these material was examined and the functions of correlations between values were obtained. The conclusion gives the analysis and the interpretation of the obtained results.
Źródło:
Archives of Foundry Engineering; 2014, 14, 2; 31-36
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of heat accumulation coefficient for oil bonded moulding sands
Autorzy:
Łągiewka, M.
Konopka, Z.
Zyska, A.
Nadolski, M.
Powiązania:
https://bibliotekanauki.pl/articles/379643.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
theoretical basis
casting processes
moulding material
oil binder
heat accumulation coefficient
moulding sand
temperature equalization coefficient
podstawy teoretyczne
proces odlewniczy
materiał formierski
spoiwo olejowe
współczynnik akumulacji ciepła
masa odlewnicza
Opis:
The possibility of controlling the solidification and cooling time of castings creates prospects of improving their structure and by the same their properties. Thermal properties of the mould constitute therefore an important factor which is necessary to consider while seeking for the mentioned improvement. The presented work illustrates the method of determining some basic thermal coefficients of moulding material, i.e. the coefficient of temperature equalisation a2, known also as the temperature diffusivity, and the heat accumulation coefficient b2, which characterises the ability of moulding material to draw away the heat from a casting. The method consists in experimental determining the temperature field within the mould during the processes of pouring, solidification and cooling of the casting. The performed measurements allow for convenient and exact calculations of the sought-after coefficients. Examinations were performed for the oil bonded moulding sand of trade name OBB SAND ‘E’. The experiment showed that the obtained value of b2 coefficient differs from the value calculated on the basis of theoretical considerations available in publications. Therefore it can be stated that theoretical calculations of the heat accumulation coefficient are thus far not sufficient and not quite reliable, so that these calculations should be verified experimentally.
Źródło:
Archives of Foundry Engineering; 2013, 13, 2; 91-94
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of the strengthening coefficient of pressure cast AlSi13Cu2/chopped carbon fibre composite
Wyznaczenie współczynnika umocnienia kompozytu AlSi13Cu2-cięte włókna węglowe odlewanego ciśnieniowo
Autorzy:
Konopka, Z.
Łągiewka, M.
Nadolski, M.
Zyska, A.
Powiązania:
https://bibliotekanauki.pl/articles/354794.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
metal matrix composites
pressure die casting
strengthening
kompozyty z osnową metaliczną (MMC)
odlewanie ciśnieniowe
umocnienie
Opis:
The purpose of the work is the determination of the strengthening coefficient for the AlSi13Cu2 alloy matrix composite reinforced with chopped carbon fibre and produced by high-pressure casting method. This coefficient was determined during the static tensile test using the Ramberg-Osgood equation. The regression relationships between strain and stress were established, serving as a basis for finding the strengthening coefficient values. The measurements and calculations were performed also for the matrix alloy itself, for the purpose of comparison. The examined coefficient decreased with an increase of fibre fraction in the composite. Its value for composite containing 15 vol. % of chopped fibre was found to be lower by 30% than the value determined for matrix alloy, what means the strengthening of the alloy to such a degree.
Celem pracy jest wyznaczenie współczynnika umocnienia kompozytu na osnowie stopu AlSi13Cu2 zbrojonego ciętymi włóknami węglowymi wytworzonego metodą ciśnieniowego odlewania. Współczynnik ten wyznaczono w statycznej próbie rozciągania korzystając z równania Ramberga-Osgooda. Opracowano regresyjne zależności odkształcenia i naprężenia, na podstawie których wyznaczono współczynnik umocnienia. Dla porównania wykonano pomiary dla stopu osnowy bez włókien. Stwierdzono zmniejszenie się tego współczynnika ze wzrostem udziału włókien w kompozycie. Jego wartość dla kompozytu zawierającego 15% obj. ciętych włókien jest o około 30% niższa od wartości wyznaczonej dla stopu osnowy, co oznacza, że materiał został w takim stopniu umocniony.
Źródło:
Archives of Metallurgy and Materials; 2013, 58, 3; 957-960
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact strength of squeeze casting AlSi13Cu2–CF composite
Autorzy:
Zyska, A.
Konopka, Z.
Łągiewka, M.
Powiązania:
https://bibliotekanauki.pl/articles/946862.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
casting composites
squeeze method
carbon fibers
impact strength
microstructure
kompozyty
metoda wyciskania
włókna węglowe
siła uderzenia
mikrostruktura
Opis:
The paper presents the results of research on microstructure and impact strength of AlSi13Cu2 matrix composite reinforced by Ni-coating carbon fibers (CF) with a volume fraction of 5%, 10% and 15%. The composite suspensions were prepared using by stirring method and subsequently squeeze casted under different pressures of 25, 50, 75 and 100 MPa. As part of the study, fiber distribution in aluminum matrix was evaluated and variation in impact strength of composite as a function of the carbon fibers volume fraction and pressure applied were determined. It has been found that the presence of Ni coating on carbon fibers clearly improves their wettability by liquid aluminum alloy and in combination with the stirring parameters applied, composite material with relatively homogeneous structure can be produced. Charpy's test showed that the impact strength of composite reaches the highest value by carrying out the squeeze casting process at 75 MPa. In the next stage of research, it was found that the impact strength of composites increases with the increase of carbon fibers volume fraction and for 15% of fibers is close to 8 J/cm2. Observations of fracture surfaces have revealed that crack growth in the composites propagates with a quasi-cleavage mechanism. During the creation of the fracture, all fibers arranged perpendicular to its surface were sheared. At the same time, the metal matrix around the fibers deformed plastically creating characteristic ductile breaks. The fracture surface formation through the fibers indicates a cohesive and strong connection of the reinforcement with the matrix. In addition to the phenomena mentioned, debonding the fiber-matrix interfaces and the formation of voids between components were observed on the fracture surface.
Źródło:
Archives of Foundry Engineering; 2020, 20, 2; 49-52
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Cast Iron Modification on Free Vibration Frequency of Casting
Autorzy:
Konopka, Z.
Łągiewka, M.
Zyska, A.
Powiązania:
https://bibliotekanauki.pl/articles/383158.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
gray cast iron
modification process
free vibration
casting
vibration frequency of casting
żeliwo szare
proces modyfikacji
drgania swobodne
odlewy
częstotliwość drgań odlewu
Opis:
The paper presents the results of investigations concerning the influence of gray cast iron modification on free vibration frequency of the disc casting. Three different chemical composition melts of gray cast iron were prepared in induction furnace. During gravity casting 0.05% and 0.3% mass of the Inolate modifier was added on stream of metal for changing graphite flakes in castings. Sound signal vibration of cast iron sample was registered by means on microphone for free vibration frequency measurements. Decreasing of free vibration frequency of modified cast iron in comparison with non modified castings was observed. Higher contents of modifier causes more decreasing of free vibration frequency. Cast iron with smaller contents of carbon and silicon have higher free vibration frequency in comparison with eutectic composition cast iron. Hardness of examined cast iron is lower when the more modifier is added during modification process. Free frequency is smaller with smaller Brinell hardness of disc casting. It was concluded that control of free vibration frequency of disc castings by means of chemical composition and modification process can improved comfort and safety of working parts.
Źródło:
Archives of Foundry Engineering; 2020, 20, 1; 23-26
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of the Home Scrap Content on the Service Life of Equipment Used in High Pressure Die Casting of AZ91 Alloy
Autorzy:
Konopka, Z.
Łągiewka, M.
Zyska, A.
Powiązania:
https://bibliotekanauki.pl/articles/383091.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
innovative casting material
innovative casting technology
automation of casting process
mechanization of casting process
guard of environment
casthouse rigging
magnesium alloy
innowacyjny materiał odlewniczy
innowacyjna technologia odlewnicza
automatyzacja procesu odlewniczego
mechanizacja procesu odlewniczego
ochrona środowiska
stop magnezu
Opis:
The results of estimation of home scrap addition in charge influence on durability and wear of casting instrumentation life in the high-pressure casting technology using the hot chamber machine of alloy of AZ91 are presented. The wear of the following elements of the casting instrumentation so-called "casting set" as: syphon, plunger, sliding-rings, nozzle and injection moulding nozzle was estimated. A wear was estimated quantitative by registering the number of mould injections for different charges to the moment of element damage supervision. A damage had to be at such level that liquidated an element from further exploitation and necessary was an exchange on new or regeneration. In a final result allowed it the detailed determination of durability of the applied rigging elements in dependence on the type of the applied type of melt. It is noticed, that together with the increase of home-scrap participation in the charge wear of pressure machine instrumentation elements increases.
Źródło:
Archives of Foundry Engineering; 2018, 18, 2; 173-176
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling of Dendritic Structure Evolution During Solidification of Al-Cu Alloy
Autorzy:
Zyska, A.
Boroń, K.
Kordas, P.
Powiązania:
https://bibliotekanauki.pl/articles/382278.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
alloy solidification
cellular automata
AlCu alloy
structure modeling
krzepnięcie stopu
automat komórkowy
stop AlCu
modelowanie struktury
Opis:
The paper presents the cellular automaton (CA) model for tracking the development of dendritic structure in non-equilibrium solidification conditions of binary alloy. Thermal, diffusion and surface phenomena have been included in the mathematical description of solidification. The methodology for calculating growth velocity of the liquid-solid interface based on solute balance, considering the distribution of the alloy component in the neighborhood of moving interface has been proposed. The influence of solidification front curvature on the equilibrium temperature was determined by applying the Gibbs Thomson approach. Solute and heat transfer equations were solved using the finite difference method assuming periodic boundary conditions and Newton cooling boundary condition at the edges of the system. The solutal field in the calculation domain was obtained separately for solid and liquid phase. Numerical simulations were carried out for the Al-4 wt.% Cu alloy at two cooling rates 15 K/s and 50 K/s. Microstructure images generated on the basis of calculations were compared with actual structures of castings. It was found that the results of the calculations are agreement in qualitative terms with the results of experimental research. The developed model can reproduce many morphological features of the dendritic structure and in particular: generating dendritic front and primary arms, creating, extension and coarsening of secondary branches, interface inhibition, branch fusion, considering the coupled motion and growth interaction of crystals.
Źródło:
Archives of Foundry Engineering; 2018, 18, 4; 87-92
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of the Dendritic Crystallization by the Cellular Automaton Method
Autorzy:
Zyska, A.
Konopka, Z.
Łągiewka, M.
Nadolski, M.
Powiązania:
https://bibliotekanauki.pl/articles/381219.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
binary alloys
crystallization
numerical modelling
cellular automata
structure modeling
stop dwuskładnikowy
krystalizacja
modelowanie numeryczne
metoda automatów komórkowych
Opis:
A numerical model of binary alloy crystallization, based on the cellular automaton technique, is presented. The model allows to follow the crystallization front movement and to generate the images of evolution of the dendritic structures during the solidification of a binary alloy. The mathematic description of the model takes into account the proceeding thermal, diffusive, and surface phenomena. There are presented the results of numerical simulations concerning the multi-dendritic growth of solid phase along with the accompanying changes in the alloying element concentration field during the solidification of Al + 5% wt. Mg alloy. The model structure of the solidified casting was achieved and compared with the actual structure of a die casting. The dendrite interaction was studied with respect to its influence on the generation and growth of the primary and secondary dendrite arms and on the evolution of solute segregation both in the liquid and in the solid state during the crystallization of the examined alloy. The morphology of a single, free-growing dendritic crystal was also modelled. The performed investigations and analyses allowed to state e.g. that the developed numerical model correctly describes the actual evolution of the dendritic structure under the non-equilibrium conditions and provides for obtaining the qualitatively correct results of simulation of the crystallization process.
Źródło:
Archives of Foundry Engineering; 2016, 16, 1; 99-106
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena efektywności czynnego uodporniania ciężarnych macior wakcyną w profilaktyce kolibakteriozy prosiąt osesków z uwzględnieniem różnych dróg podawania preparatu
Ocenka ehffektivnosti aktivnojj immunizacii suporosnykh svinomatok vakcinojj v profilaktike kolibakterioza sosushhikh porosjat, s uchetom raznykh sposobov podachi preparata
Estimation of the efficiency of active immunization of farrow sows with vaccine in the prophylaxy of colibacteriosis of suckling piglets taking into consideration different drug administration ways
Autorzy:
Furowicz, A.
Zyska, W.
Loczewski, P.
Powiązania:
https://bibliotekanauki.pl/articles/798018.pdf
Data publikacji:
1990
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
lochy prosne
wakcyna
kolibakterioza
prosieta
preparaty
trzoda chlewna
hodowla
antygeny
pregnant sow
vaccine
colibacteriosis
piglet
preparation
pig
animal breeding
antigen
Opis:
Целью настоящего труда была оценка эффективности 5 видов вакйин изготовляемых на базе местного энтеротоксичного серотина Е. coli (Мун 987) в борьбе с колибактериозом сосущим поросят. Вакцинации подвергали 3 группы супоросных свиноматок (по 10 голов), применяя инактивированные вакцины перорально и подкожно, а жизнеспособную вакцину перорально. Потомство указанных свиноматок заражали непосредственно после рождения штаммом Мун 1413, имеющим только один общий компонент со штаммом Мун 987 - фимбриальный антиген. Установлено, что иммунизация супоросных свиноматок вакцинами изготовленными на базе местных фимбриальных энтеротоксичных штаммов Е. coli хранит их потомсто против болезни. Она приводит также к лучшему росту поросят на 1-ой неделе жизни и позволяет сократить период предродовой акклиматизации супоросных свиноматок. Установлено, что наиболее эффективно действует вакцина содержащая живые бактерии подаваемая перорально и инактивированная вакцина подаваемая подкожно.
The aim of the respective investigations was to assess the efficiency of 3 vaccine kinds produced on the basis of a local enterotoxic E. coli serotype (Moon 987) in the prophylaxy of colibacteriosis of suckling piglets. Three groups of farrow sows (by 10 heads) at administration of the inactivated vaccines per os and subcutaneously and the vital vaccine per os. The offsping of these sows was infected close after birth with the enterotoxin Moon 987 strain - fimbrial antigen. It has been found that the immunization of farrow sows with vaccines prepared on the basis of local, fimbrial enterotxic E. coli strains protects their offspring against the disease. It results also in a better growth of piglets in the 1st week of life and allows to shorten the prepartum acclimatization period of farrow sows. It has been found that the most efficient is the vaccine containing living bacteria administered per os and the inactivated vaccine administered subcutaneously.
Źródło:
Zeszyty Problemowe Postępów Nauk Rolniczych; 1990, 384
0084-5477
Pojawia się w:
Zeszyty Problemowe Postępów Nauk Rolniczych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of squeeze parameters and modification of AlSi7Mg alloy
Autorzy:
Zyska, A.
Konopka, Z.
Łągiewka, M.
Nadolski, M.
Powiązania:
https://bibliotekanauki.pl/articles/381007.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
mechanical properties
Al alloy
squeeze casting technology
modification
właściwości mechaniczne
stop Al
technologia prasowania
modyfikacja
Opis:
The paper present the examination results concerning mechanical properties of castings made of AlSi7MG alloy in correlation both with the most significant squeeze casting parameters and with the modification treatment. Experiments were planned and held according to the 23 factorial design. The regression equations describing the influence of the squeeze pressure, the mould temperature, and the quantity of strontium modifier on the strength and elongation of the examined alloy were obtained. It was found that the main factor controlling the strength increase is the squeeze pressure, while the plasticity (A5) of the alloy is affected most advantageously by modification. The application of modification treatment in squeeze casting technology enables for production of the slab-type castings made of AlSi7Mg alloy exhibiting strength at the level of 230 MPa and elongation exceeding 14%.
Źródło:
Archives of Foundry Engineering; 2013, 13, 2; 113-116
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physical and Numerical Modeling of Duplex Cast Steel Thin-Walled Castings
Autorzy:
Stradomski, G.
Nadolski, M.
Zyska, A.
Kania, B.
Rydz, D.
Powiązania:
https://bibliotekanauki.pl/articles/351674.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
duplex cast steel
centrifugal casting
gravity casting
thin-walled castings
Opis:
The paper, which is a summary and supplement of previous works and research, presents the results of numerical and physical modeling of the GX2CrNiMoCuN25-6-3 duplex cast steel thin-walled castings production. To obtain thin-walled castings with wall in the thinnest place even below 1 mm was used the centrifugal casting technology and gravity casting. The analyzed technology (centrifugal casting) enables making elements with high surface quality with reduced consumption of batch materials and, as a result, reducing the costs of making a unitary casting. The idea behind the production of cast steel with the use of centrifugal technology was to find a remedy for the problems associated with unsatisfactory castability of the tested alloy. The technological evaluation of the cast construction was carried out using the Nova Flow & Solid CV 4.3r8 software. Numerical simulations of crystallization and cooling were carried out for a casting without a gating system and sinkhead located in a mold in accordance with the pouring position. It was assumed that the analyzed cast will be made in the sand form with dimensions 250×250×120 mm.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 4; 1449-1456
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porosity of Castings Produced by the Vacuum Assisted Pressure Die Casting Method
Autorzy:
Zyska, A.
Konopka, Z.
Łągiewka, M.
Nadolski, M.
Powiązania:
https://bibliotekanauki.pl/articles/379699.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
innovative foundry technology
aluminium alloy
vacuum assisted pressure
die casting
casting defect
porosity
innowacyjna technologia odlewnicza
stop aluminium
formowanie podciśnieniowe
odlewanie ciśnieniowe
wada odlewu
porowatość
Opis:
The paper presents the results of investigations concerning the influence of negative (relative) pressure in the die cavity of high pressure die casting machine on the porosity of castings made of AlSi9Cu3 alloy. Examinations were carried out for the VertaCast cold chamber vertical pressure die casting machine equipped with a vacuum system. Experiments were performed for three values of the applied gauge pressure: -0.3 bar, -0.5 bar, and -0.7 bar, at constant values of other technological parameters, selected during the formerly carried initial experiments. Porosity of castings was assessed on the basis of microstructure observation and the density measurements performed by the method of hydrostatic weighing. The performed investigation allowed to find out that – for the examined pressure range – the porosity of castings decreases linearly with an increase in the absolute value of negative pressure applied to the die cavity. The negative pressure value of -0.7 bar allows to produce castings exhibiting porosity value less than 1%. Large blowholes arisen probably by occlusion of gaseous phase during the injection of metal into the die cavity, were found in castings produced at the negative pressure value of -0.3 bar. These blowholes are placed mostly in regions of local thermal centres and often accompanied by the discontinuities in the form of interdendritic shrinkage micro-porosity. It was concluded that the high quality AlSi9Cu3 alloy castings able to work in elevated temperatures can be achieved for the absolute value of the negative pressure applied to the die cavity greater than 0.5 bar at the applied set of other parameters of pressure die casting machine work.
Źródło:
Archives of Foundry Engineering; 2015, 15, 1; 125-130
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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