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Wyświetlanie 1-15 z 182
Tytuł:
Incidence of Phytophthora infestans (Mont.) de Bary on potato and tomato in Maine, 2006–2010
Autorzy:
Olanya, O.M.
Larkin, R.P.
Honeycutt, C.W.
Powiązania:
https://bibliotekanauki.pl/articles/66822.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Late blight, caused by Phytophthora infestans (Mont.) de Bary, is a devastating disease which is found worldwide. In Maine, United States (US), we recorded late blight on potato and tomato during the 2006–2009 cropping seasons. From 2006 to 2008, over 90% of the diseased samples were collected in potato fields from northern and central Aroostook County in Northern Maine, US. Then, in 2009, an unprecedented influx of inoculum on infected tomato transplants shipped to retail garden centers throughout the Northeast US significantly changed the late blight infection patterns. In 2009, 43% of diseased samples obtained were from tomato, and 57% from potato, and disease was found to occur all over the state. Moran’s index and spatial autocorrelation analysis of disease occurrence, geographical locations, host factors, and infection levels from previous years, were not statistically significant (p > 0.05). Therefore, random distributions of late blight incidences were recorded across locations and years. Nearest neighbor analysis revealed that mean spatial distances for late blight occurrence ranged from 1.51 to 71.4 km from 2006 to 2008, and 7.4 to 126.5 km in 2009. The frequency and locations of late blight outbreaks in 2009 were substantially greater than in 2006, 2007, and 2008, as affected by the influx of inoculum and movement of infected tomato seedlings as well as conducive environmental conditions. All were contributing factors for late blight occurrence in Maine. In 2010, few disease samples were collected, indicating that the influx of inoculum in 2009 did not persist to cause widespread disease in 2010. The reduction of inocula sources, fungicide protection of susceptible hosts, and the removal and destruction of infected tomato seedlings and potato cull piles or volunteer plants, can greatly reduce late blight occurrences and improve potato production. These actions should be considered as an integral part of late blight management programmes in regions where late blight commonly occurs.
Źródło:
Journal of Plant Protection Research; 2015, 55, 1
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First report of Pythium aphanidermatum infecting tomato in Egypt and its control using biogenic silver nanoparticles
Autorzy:
Elshahawy, I.
Abouelnasr, H.M.
Lashin, S.M.
Darwesh, O.M.
Powiązania:
https://bibliotekanauki.pl/articles/66024.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Pythium aphanidermatum
plant disease
tomato
Lycopersicon esculentum
Egypt
pest control
biogenic substance
silver nanoparticle
Opis:
In August 2016, tomato plants grown during a hot, wet summer with heavy soil flooding, displaying symptoms of wilting, dead plant, root rot with crown and stem rot, at Beni Suef and Fayoum governorates were examined. A number of 16 fungal isolates were isolated from tomato plants displaying the above symptoms. These isolates were classified as belonging to six species, namely: Alternaria solani, Chaetomium globosum, Fusarium solani, Fusarium oxysporum, Pythium spp. and Rhizoctonia solani. Isolates of Pythium spp. were prevalent and were found to be more pathogenic than the other fungal isolates. This species causes damping-off, root rot, sudden death, stem rot and fruit rot. The pathogen was identified as Pythium aphanidermatum based on morphological, cultural, and molecular characteristics. Biogenic silver nanoparticles (AgNPs) were produced using the F. oxysporum strain and characterized by transmission electron microscopy (TEM). The size of these spherical particles ranged from 10 to 30 nm. In vitro, biogenic AgNPs showed antifungal activity against P. aphanidermatum. In greenhouse and field experiments, AgNPs treatment significantly reduced the incidence of dead tomato plants due to root rot caused by P. aphanidermatum compared to the control. All of the investigated treatments were effective and the treatment of root dipping plus soil drenching was the most effective. To the best of our knowledge, this study describes P. aphanidermatum on tomato in Egypt for the first time. Also, biogenic AgNPs could be used for controlling root rot disease caused by this pathogen.
Źródło:
Journal of Plant Protection Research; 2018, 58, 2
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of arbuscular mycorrhizal fungal inoculations on the growth and polyphenol levels of garden leek (Allium porrum)
Autorzy:
Nasir, M.S.A.
Nunez, A.
McKeever, L.C.
Olanya, O.M.
Powiązania:
https://bibliotekanauki.pl/articles/66601.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
plant height
polyphenol content
root colonization
shoot weight
root weight
fungi
fungal spore
Rhizophagus intraradices
Gigaspora margarita
Glomus geosporum
Paraglomus occultum
Claroideoglomus claroideum
arbuscular mycorrhizal fungi
inoculation
garden leek
Allium porrum
Opis:
Arbuscular mycorrizal (AM) fungi may enhance plant growth and polyphenol production, however, there have been limited studies on the relationships between root colonization of different fungal species and polyphenol production on cultivated Allium porrum (garden leek). The effects of inoculation of AM fungi spores from Rhizophagus intraradices, Giga -spora margarita, Glomus geosporum, Paraglomus occultum, Claroideoglomus claroideum, and Glomus species on colonization of garden leek roots and symbiotic changes in polyphenol production and plant growth were evaluated in greenhouse experiments. There were significant differences (p < 0.05) in colonization of leek roots by AM fungi species. The greatest level of root colonization was recorded on plants inoculated with R. intraradices (73%) and the lowest level on C. claroideum (3.2%). Significant differences (p < 0.05) in plant height were recorded between AM inoculated plants and the controls. Polyphenol levels differed significantly (p < 0.05) between garden leek plants inoculated with AM fungi and the non-inoculated controls. The percentage increases in polyphenol (a derivative of kaempferol) on garden leeks inoculated with G. geosporum relative to the untreated controls ranged from 28 to 1123%. Due to symbiosis with different AM species, other polyphenols decreased in some instances (negative values) and increased in others for values of up to 590%. Results showed that AM fungi species exhibited remarkable differences in polyphenol levels in garden leeks. The high polyphenol production by garden leek plants inoculated with G. geosporum, and Glomus species could be exploited for enhanced resistance of garden leeks to insects and diseases. This research highlights an understudied area, notably the relationships between AM fungal inoculations, root colonizations and polyphenol production in garden leeks. The findings can be utilized to improve pest resistance and the quality of garden leek plants.
Źródło:
Journal of Plant Protection Research; 2018, 58, 1
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Survival potential of Phytophthora infestans sporangia in relation to environmental factors and late blight occurrence
Autorzy:
Olanya, O.M.
Anwar, M.
He, Z.
Larkin, R.P.
Honeycutt, C.W.
Powiązania:
https://bibliotekanauki.pl/articles/65009.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
survival
Phytophthora infestans
sporangia
environmental factor
late blight
occurrence
climate variability
potato
tomato
Opis:
Potato is an important crop globally and late blight (Phytophthora infestans) often results in severe crop loss. The cost for late blight control can be in excess of $210 million in the United States. We utilised a non-parametric density distribution analysis of local temperature (T) and relative humidity (RH), from 2005 to 2009, to assess and validate sporangia survival potential using survival model and late blight risks during the potato cropping season at Presque Isle, in the northern part of the state of Maine, USA. Modelbased analyses showed that ambient temperatures of 3−30°C and RH values of 45−100% were conducive for sporangia survival. Disease outbreaks and risk periods coincided with a high sporangia survival probability (15−35%). Due to the omission of solar radiation (SR) in the computation of survival potential in previous research, we applied a Cox proportional model to estimate the probability of sporangia survival [i.e. hazard at a specific time H(t)] as a function of baseline hazard (H0) and the influencing parameters. The model is: H(t) = H0(t) × exp(0.067ET + 0.138T + 0.083RH + 0.001SR) where ET is exposure time. The survival model indicated that RH (β = 0.083) and T (β = 0.138) were significant (p < 0.05) factors in sporangia survival in comparison to SR (β = 0.001). The hazard ratio, indicative of sporangia survival risk, varied with the predictors. For the unit increase of T, sporangia survival hazard increased by 1.148 times. The Cox model and sporangia hazard probabilities can be used for short-term disease forecasts based on the risk period most conducive for pathogen survival and targeted fungicide applications for optimum late blight management.
Źródło:
Journal of Plant Protection Research; 2016, 56, 1
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparing measures of religiosity and spirituality in the experience of emotions – Development and Validation of a Scale of Non-Spiritual Religiosity
Autorzy:
Da Silva, João P.
Pereira, Anabela M.S.
Monteiro, Sara O.M.
Bartolo, Ana
Powiązania:
https://bibliotekanauki.pl/articles/2122002.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Religiosity
spirituality
emotions
scale
psychology
Opis:
This study aimed to compare measures of religiosity and spirituality in the experience of positive and negative emotions. For this purpose, a measure of non-spiritual religiosity (Religious Sense Scale) was developed. Method: The study has been conducted on a sample of 279 participants aged between 19 and 69 (M=24.42, SD=9.463) who completed a questionnaire that included the Religious Sense Scale, the Portuguese version of the Spiritual Well-being Questionnaire and the abridged Portuguese version of the Positive and Negative Affect Schedule. Findings: The was found to have excellent metrical properties for the measurement of religiosity or “religious sense”. Religious individuals differ from spiritual ones in the experience of emotions: spirituality tends to a greater experience of positive affect and religiosity to negative affect.
Źródło:
Polish Psychological Bulletin; 2020, 51, 1; 51-61
0079-2993
Pojawia się w:
Polish Psychological Bulletin
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Drummondin E and Flinderole B are potential inhibitors of RNA-dependent RNA polymerase of SARS-CoV-2: an in silico study
Autorzy:
Akhtar, N.
Verma, H.
Silkari, O.M.
Upadhyay, A.K.
Kaushik, V.
Mannan, M.A.
Powiązania:
https://bibliotekanauki.pl/articles/2096249.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
RNA polymerase
SARS-CoV-2
RNA-dependent
Drummondin E
Flinderole B
Opis:
Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected 235.6 million people worldwide. In the present study, RNA-dependent RNA polymerase (RdRp) (PDB Id: 6M71) of SARS-CoV-2, an essential enzyme needed for subgenomic replication and amplification of RNA, was selected. Similar to other RdRps, it is a conserved protein and a popular target for antiviral drug therapy. Based on a computational approach, potential RdRp inhibitors were identified. The absorption, distribution, metabolism, excretion, and toxicity (ADMET) of selected molecules were determined using computation tools. The potential inhibitors were docked to the RdRp and later confirmed by Molecular Dynamics (MD) using the “Flare” module of Cresset software. Drummondin E and Flinderole B had higher drug similarity scores among the compounds selected in this study. Both these compounds are noncarcinogenic, nonirritant, nontumorigenic, and nonmutagenic. Molecular docking studies showed that both compounds can bind to RdRp. The best ligand interaction patterns were validated by MD using the “Flare” module. MD was performed for the period of 100 ns with the time step of 1 fs. The simulation results suggest that Thr-680, Arg-624, Lys-676, and Val-557 are key interacting partners in the Drummondin E-RdRp complex, while Asp-618, Asp-760, Asp-623, Arg-624, and Asp-761 are the interacting partners in the Flinderole B-RdRp complex. Based on the in silico drug-likeness score; ADMET properties; and molecular simulation result, we surmise that Flinderole B and Drummondin E could impede SARS-CoV-2 genome replication and transcription by targeting the RdRp protein.
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2022, 103, 1; 53-70
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of lycopene and astaxanthin in feed on metabolic parameters of laying hens, yolk color of eggs and their content of carotenoids and vitamin A when stored under refrigerated conditions
Autorzy:
Shevchenko, L.V.
Iakubchak, O.M.
Davydovych, V.A.
Honchar, V.V.
Ciorga, M.
Hartung, J.
Kołacz, R.
Powiązania:
https://bibliotekanauki.pl/articles/2087136.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
feed additives
antioxidants
laying hens
blood biochemical parameters
egg yolkquality
Źródło:
Polish Journal of Veterinary Sciences; 2021, 24, 4; 525-535
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance evaluation of unreliable system with infinite number of servers
Autorzy:
Tikhonenko, O.
Ziółkowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/201519.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
queueing systems with non-homogeneous customers
unreliable queueing systems
total volume
loss probability
Laplace–Stieltjes transform
Opis:
In the paper, we investigate queueing system M/G/∞ with non-homogeneous customers. By non-homogeneity we mean that each customer is characterized by some arbitrarily distributed random volume. The arriving customers appear according to a stationary Poisson process. Service time of a customer is proportional to his its volume. The system is unreliable, which means that all its servers can break simultaneously and then the repair period goes on for random time having an arbitrary distribution. During this period, customers present in the system and arriving to it are not served. Their service continues immediately after repair period termination. Time intervals of the system in good repair mode have an exponential distribution. For such system, we determine steady-state sojourn time and total volume of customers present in it distributions. We also estimate the loss probability for the similar system with limited total volume. An analysis of some special cases and some numerical examples are attached as well.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2020, 68, 2; 289-297
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modifications of Range-Doppler Algorithm for Compensation of SAR Platform Motion Instabilities
Autorzy:
Gorovyi, I. M.
Bezvesilniy, O. O.
Vavriv, D. M.
Powiązania:
https://bibliotekanauki.pl/articles/226865.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Synthetic Aperture Radar (SAR)
SAR
range-Doppler algorithm
RDA
multi-look processing
image formation
radiometric errors
autofocus
Opis:
Two modifications of the range-Doppler algorithm (RDA) have been proposed to solve problems of SAR platform motion instabilities. First, the multi-look processing based on the RDA with an extended Doppler bandwidth has been introduced for correction of radiometric errors. Second, the RDA has been modified to perform SAR image formation on short-time acquisition intervals to use it in a recently-developed local-quadratic map-drift autofocus (LQMDA) method. The performance of the methods is illustrated with experimental data obtained by airborne SAR systems.
Źródło:
International Journal of Electronics and Telecommunications; 2014, 60, 3; 225-231
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Single-server queueing system with external and internal customers
Autorzy:
Tikhonenko, O.
Ziółkowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/199838.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
single-server queueing system with non-homogeneous customers
random volume customers
loss probability
total volume distribution
Laplace transform
Laplace-Stieltjes transform
RAM memory space
prawdopodobieństwo straty
transformacja Laplace'a
transformata Laplace'a-Stieltjesa
pamięć RAM
Opis:
In the paper, we investigate a single-server queueing system with unlimited memory space and non-homogeneous customers (calls) of the two following types: 1) external customers that are served by the system under consideration, 2) internal customers that arrive and interrupt the service process only when an external customer is being served. The external customers appear according to a stationary Poisson process. Customers of each of the above-mentioned types are characterized by some random volume. The customer service time depends arbitrarily on its volume. Two schemes of customer service organization are analyzed. The non-stationary and stationary distributions of the total volume of customers present in the system are determined in terms of Laplace and Laplace-Stieltjes transforms. The stationary first and second moments of total customers volume are also calculated. The obtained results are used to approximate loss characteristics in analogous systems with limited buffer space. Numerical examples illustrating theoretical results are attached as well.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2018, 66, 4; 539-551
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Base Station Energy Efficiency Improvement for Next Generation Mobile Networks
Autorzy:
Mwashita, W.
Odhiambo, M. O.
Powiązania:
https://bibliotekanauki.pl/articles/226847.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
energy efficiency
Base Station sleeping
CO2 emissions
heterogeneous networks
mobile networks
next generation networks
operational expenditure (OPEX)
Opis:
As more and more Base Stations (BSs) are being deployed by mobile operators to meet the ever increasing data traffic, solutions have to be found to try and reduce BS energy consumption to make the BSs more energy efficient and to reduce the mobile networks' operational expenditure (OPEX) and carbon dioxide emissions. In this paper, a BS sleeping technology deployable in heterogeneous networks (HetNets) is proposed. The proposed scheme is validated by using extensive OMNeT++/SimuLTE simulations. From the simulations, it is shown that some lightly loaded micro BSs can be put to sleep in a HetNet when the network traffic is very low without compromising the QoS of the mobile network.
Źródło:
International Journal of Electronics and Telecommunications; 2017, 63, 2; 187-194
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational fluid dynamics (CFD) simulation of liquid-liquid mixing in mixer settler
Zastosowanie obliczeniowej mechaniki płynów do symulacji mieszania ciecz-ciecz w ekstraktorze
Autorzy:
Shabani, M. O.
Mazahery, A.
Powiązania:
https://bibliotekanauki.pl/articles/354518.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ekstraktor
CFD
mieszanie
mixer settler
mixing
Opis:
Mixer-settlers are widely used inmetallurgical, mineral and chemical process. One of the greatest challenges in the area of hydrometallurgy process simulation is agitation made by impeller inside mixer-settler which yet presents one of the most common operations. Computational fluid dynamics (CFD) model has been developed to predict the effect of different physical parameters including temperature and density on the mixing characteristics of the system. It is noted that non-isotropic nature of flow in a mixer-settler, the complex geometry of rotating impellers and the large disparity in geometric scales present are some of the factors which contribute to the simulation difficulty. The experimental data for different velocity outlet was also used in order to validate the model.
Mieszanie w ekstraktorze (mieszalniku-odstojniku) jest jedną z najczęstszych operacji, ale stanowi jedno z największych wyzwań dla symulacji komputerowej. Ekstraktory zazwyczaj zawierają wirnik zamontowany na wale, i ewentualnie mogą zawierać przegrody. W niniejszej pracy badano właściwości hydrodynamiczne ekstraktorów. Zbadano wpływ różnych parametrów fizycznych, temperatur i gęstości, na mieszanie w układzie. Model oparty na obliczeniowej mechanice płynów (Computational Fluid Dynamics) zostałopracowany w celu przewidywania charakterystyki mieszania. Model zostałzweryfikowany za pomocą danych doświadczalnych dla różnych szybkości stosowanych w pracy. Praca pozwoliła na zwiększenie efektywności ekstraktorów, które mogą charakteryzować się wyższymi parametrami niż te podawane w literaturze.
Źródło:
Archives of Metallurgy and Materials; 2012, 57, 1; 173-178
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of wear mechanisms in sintered Fe-1.5 Wt % Cu alloys
Charakterystyka mechanizmów zużycia spiekanych stopów Fe-1.5Cu
Autorzy:
Mazahery, A.
Shabani, M. O.
Powiązania:
https://bibliotekanauki.pl/articles/354551.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
właściwości tribologiczne
proszki spiekane
porowatość
tribological properties
powder processing
porosity
Opis:
In this research, increasing amount of ultimate tensile strength and hardness in sintered Fe-1.5 Wt % Cu alloys is observed with increasing the density. The influence of different applied pressure of 300, 450, 600 and 750 MPa on porosity and wear behavior has been also studied. Cross-section micrographs of worn surfaces show that the pores are closed by plastic deformation or oxides and metallic particles after the wear test. According to the wear test results, specimens with 14 vol. % porosity are more wear resistant than the specimens with low porosity values of 11 vol. %. Thus, oxidation wear and surface plastic deformation are the main wear mechanisms identified in this investigation. Abrasion wear was also characterized as the result of abrasive debris agglomeration and the asperities of the pins.
Obserwowano wzrost wytrzymałości na rozciąganie i twardości spiekanych stopów Fe-1.5Cu (% wag) wraz ze wzrostem ich gęstości. Badano także wpływ różnych wartości ciśnienia 300, 450, 600 i 750 MPa na porowatość i zużycie stopów. Mikrofotografie przekrojów zużytych powierzchni pokazują, że po teście zużycia pory są zamknięte wskutek odkształcenia plastycznego lub przez tlenki i cząstki metaliczne. Według wyników badań zużycia próbki o porowatości 14% są bardziej odporne na zużycie niż próbki o niższej porowatości 11%. Utlenianie i odkształcenie plastyczne powierzchni to główne mechanizmy zużycia zidentyfikowane w tej pracy. Stwierdzono także, że ścieranie jest wynikiem aglomeracji ściernych drobin i nierówności pinów.
Źródło:
Archives of Metallurgy and Materials; 2012, 57, 1; 93-103
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interaction of Titanium with Ceramic Molds in the Conditions of Electron Beam Casting Technology
Autorzy:
Kaliuzhnyi, P.
Voron, M.
Mykhanian, O.
Tymoshenko, A.
Neima, O.
Iangol, O.
Powiązania:
https://bibliotekanauki.pl/articles/2079826.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
investment casting
electron beam casting
titanium
ceramic shell mold
technologie odlewania
wiązka elektronów
tytan
formy ceramiczne
Opis:
For the manufacture of near net shape complex titanium products, it is necessary to use investment casting process. Melting of titanium is promising to carry out by electron beam casting technology, which allows for specific processing of the melt, and accordingly control the structure and properties of castings of titanium alloys. However, the casting of titanium in ceramic molds is usually accompanied by a reaction of the melt with the mold. In this regard, the aim of the work was to study the interaction of titanium melt with ceramics of shell molds in the conditions of electron beam casting technology. Ceramic molds were made by using the following refractory materials – fused corundum Al2O3, zircon ZrSiO4 and yttria-stabilized zirconium oxide ZrO2, and ethyl silicate as a binder. Melting and casting of CP titanium was performed in an electron beam foundry. Samples were made from the obtained castings and electron microscopic metallography was performed. The presence and morphology of the altered structure, on the sample surface, were evaluated and the degree and nature of their interaction were determined. It was found that the molds with face layers of zirconium oxide (Z1) and zircon (ZS1) and backup layers of corundum showed the smallest interaction with the titanium melt. Corundum interacts with titanium to form a non-continuous reaction layer with thickness of 400-500 μm. For shell molds with face and backup layers of zircon on the surface of the castings, a reaction layer with thickness of 500-600 μm is formed. In addition, zirconium-silicon eutectic was detected in these layers.
Źródło:
Archives of Foundry Engineering; 2021, 21, 3; 27-32
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 182

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