Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "AraB." wg kryterium: Autor


Tytuł:
Competitive Nucleation in Grey Cast Irons
Autorzy:
Arab, N.
Powiązania:
https://bibliotekanauki.pl/articles/382159.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cast iron
competitive nucleation
undercooling
cooling curve
grain refining
żeliwo
nukleacja
przechłodzenie
krzywa krzepnięcia
rozdrabnianie ziarna
Opis:
Cast irons are good examples of materials which are more sensitive to chemical composition and production conditions. In this research to improve casting quality, solidification and nucleation process in grey cast iron was investigate. In particular, attempts have been made to rationalize variation in eutectic cells with nucleation sites and eutectic solidification undercooling. Four castings with different diameter and similar chemical composition and pouring temperature and different inoculant percentage was casted. The cooling curve and maximum and minimum undercooling for each castings was measured. Also optical metallography and image analyzer has been used to determine the average eutectic cells diameter, and linear and surface densities, and volume density was calculated. The results of this research show a competitive behavior between nucleation sites and eutectic undercooling. Higher nucleation sites and higher eutectic undercooling cause higher eutectic cell density. But increasing nucleation sites by introducing inoculants to molten metal, is accompanied with reduction in eutectic undercooling. It means that inoculation and undercooling have opposite effect on each other. So, to achieve maximum cell density, it is necessary to create an optimization between these parameters.
Źródło:
Archives of Foundry Engineering; 2017, 17, 4; 185-189
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of the Elaboration Conditions on the Structural, Morphological and Luminescence Properties of ZnO Nanopowders
Autorzy:
Arab, L.
Guergouri, K.
Powiązania:
https://bibliotekanauki.pl/articles/1401219.pdf
Data publikacji:
2015-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.Dz
81.07.Wx
81.20.Fw
07.57.Ty
78.55.Qr
68.37.Hk
Opis:
Pure ZnO nanopowders were synthesized by the sol-gel method, which has several advantages, among which we include, achieving low temperature deposition and synthesis of new hybrid organo-mineral materials. The effect of the elaboration conditions (the elaboration concentrations ratio of precursors $(C_{Z}//C_{A})$, the gelling temperature $(T_g)$ and the gelling time $(t_g)$) on the structural, morphological and luminescence properties of ZnO nanopowders has been investigated. The chemical composition of the powders, determined by FTIR spectroscopy, indicate the exclusive presence of Zn-O bonds, as it is shown by the XRD spectra. The XRD results indicate also that the synthesized ZnO powder is a solid solution, crystallizing in pure würtzite structure with a minimum grain size of about 23 nm for the powders prepared using: $C_{Z}//C_{A}$=0.06%, $T_g$=130°C and $T_g$=4 h. The morphological aspect, given by the SEM images, revealed that the powders are made of sheets, consisting of small particles agglomerated together. The photoluminescence study of the ZnO powders shows spectra with luminescence peaks from green to ultraviolet light, the more intensive emission is connected to the peaks of the blue luminescence.
Źródło:
Acta Physica Polonica A; 2015, 127, 4; 940-942
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Humour and belonging: a thematic review
Autorzy:
Arab, Reza
Milner Davis, Jessica
Powiązania:
https://bibliotekanauki.pl/articles/2098506.pdf
Data publikacji:
2022-08-11
Wydawca:
Krakowskie Towarzystwo TERTIUM
Tematy:
humour
laughter
belonging
inclusion
exclusion
Opis:
Serving as introduction to this Special Issue, this article presents a thematic review of topics involved in studies on humour and belonging. It briefly elaborates on the intricacies of concepts such as humour, sense of humour and belonging and their relationships. It then provides a selective review of some major relevant studies. Finally, the themes and contents of the Special Issue are introduced.
Źródło:
The European Journal of Humour Research; 2022, 10, 2; 1-13
2307-700X
Pojawia się w:
The European Journal of Humour Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Globotriaosyl ceramide (Gb_3) expression in human tumour cells: Intracellular trafficking defines a new retrograde transport pathway from the cell surface to the nucleus, which correlates with sensitivity to verotoxin
Autorzy:
Lingwood, Clifford
Khine, Aye
Arab, Sara
Powiązania:
https://bibliotekanauki.pl/articles/1044809.pdf
Data publikacji:
1998
Wydawca:
Polskie Towarzystwo Biochemiczne
Źródło:
Acta Biochimica Polonica; 1998, 45, 2; 351-359
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Taguchi Method for Investigating the Mechanical Properties of a Microalloyed Steel
Zastosowanie metody Taguchi do badania właściwości mechanicznych stali niskostopowych
Autorzy:
Ayaz, M.
Arab, N. B.
Khaki, D. M.
Powiązania:
https://bibliotekanauki.pl/articles/353590.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Taguchi method
strain hardening exponent
yield strength
microalloyed steel
hot rolling
metoda Taguchi
wykładnik utwardzenia
granica plastyczności
stal niskostopowa
walcowanie na gorąco
Opis:
In the present investigation, the effects of processing parameters, such as roughing, finishing and coiling temperatures, on the strain hardening exponent and yield strength of a Nb-microalloyed steel has been studied by Taguchi method. In order to achieve maximum n-value and yield strength, tests were done in a laboratorial pilot considering a L16 orthogonal array of Taguchi method under following condition: roughing temperature of 1000, 1050, 1100, 1150°C, finishing temperature of 800, 850, 900, 950°C, coiling temperature of 550, 600, 650, 700°C. Then, analysis of variance and signal to noise ratios are performed on the measured data. The results indicated that the finishing and coiling temperatures were the major factor affecting the mechanical properties. The confirmation tests at optimal conditions approve the effectiveness of this robust design methodology in investigating the hot rolling process of the microalloyed steels.
W niniejszej pracy, metodą Taguchi badano wpływ parametrów obróbki takich jak temperatura obróbki zgrubnej, wykańczającej i zwijania na wykładnik utwardzenia i granicę plastyczności stali niskostopowej. W celu uzyskania maksymalnej wartości wykładnika n i granicy plastyczności, badania przeprowadzono w skali laboratoryjnego pilota uwzględniając ortogonalną macierz L16 metody Taguchi pod następującymi warunkami: temperatura obróbki zgrubnej: 1000, 1050, 1100, 1150° C, temperatura obróbki wykańczającej: 800, 850, 900, 950° C, temperatura zwijania: 550, 600, 650, 700° C. Następnie dokonano analizy wariancji stosunku sygnału do szumu na zmierzonych danych. Wyniki wskazują, że temperatury obróbki wykończeniowej i zwijania były głównym czynnikiem wpływającym na własności mechaniczne. Testy przeprowadzone w optymalnych warunkach potwierdziły skuteczności zaprojektowanej metodologii w badaniach procesu walcowania na gorąco stali niskostopowych.
Źródło:
Archives of Metallurgy and Materials; 2014, 59, 3; 853-858
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shear strength of compacted Chlef sand: effect of water content, fines content and others parameters
Autorzy:
Bouri, Djamel
Krim, Abdallah
Brahim, Abdelkader
Arab, Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/178905.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fines content
water content
direct shear test
friction angle
cohesion
Opis:
This paper presents a laboratory study of the combined effect of the water content and fines content on the mechanical behaviour of Chlef sand in a medium dense state (RD = 65%) and dense state (RD = 80%). Several mechanical parameters were evaluated such as shear strength, cohesion and friction angle at different water content w = 0, 1, 2 and 3% and different fines content Fc = 0, 10, 20, 30 and 40%. The test results showed that the shear strength of Chlef sand decrease with the increase fines content Fc = 0 to 40%, our tests result also showed that the water content has a significant influence on the shear strength which decreases with the increase in the water content w = 0 to 3%. The fines content and the water content have a significant influence on the mechanical parameters c and ɸ. Cohesion increases with the percentage of fines and decreases with the increase of the water content while the friction angle decreases with the increase the fines content and the water content.
Źródło:
Studia Geotechnica et Mechanica; 2020, 42, 1; 18-35
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Economical reactive powder concrete cast using available materials in North Sinai, Egypt
Autorzy:
Meleka, N. N.
Bashandy, A. A.
Arab, M. A.
Powiązania:
https://bibliotekanauki.pl/articles/231066.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
proszek reaktywny
beton
właściwości mechaniczne
zawartość
cement
pył krzemionkowy
włókno stalowe
reactive powder
concrete
mechanical properties
silica fume
steel fiber
Opis:
In this research reactive powder concrete (RPC) was prepared using sand from North Sinai. The mechanical properties of locally cast RPC were investigated and evaluated by studying the effects of using different cement and silica fume contents and new steel fibers’ aspect ratios as reinforcement for RPC. Specimens’ preparation, curing regimes and testing procedures to evaluate the compressive strength, the modulus of elasticity, the indirect tensile strength and the flexural strength were discussed. A compressive strength of 154.5MPa, indirect tensile strength of 11.98MPa, modulus of elasticity of 45.1GPa and flexural strength of 30.26MPa have been achieved for reinforced RPC contains 800 kg/m3 cement content and silica fume content 30% of cement weight. The test results showed some improvements by increasing cement and silica fume contentsas well as adding steel fibers on the compressive strength, modulus of elasticity and indirect tensile strength.
Źródło:
Archives of Civil Engineering; 2013, 59, 2; 175-195
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shear Strength Enhancement of Cemented Reinforced Sand: Role of Cement Content on the Macro-Mechanical Behavior
Autorzy:
Boutouba, Kheira
Benessalah, Ismail
Arab, Ahmed
Henni, Ahmed Djafar
Powiązania:
https://bibliotekanauki.pl/articles/178198.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
cemented reinforced sand
direct shear test
water content
curing time
dilatant character
Opis:
Sands reinforced by hydraulic binders (cement) have constituted in recent decades a major asset for the expansion of several areas of engineering. The mechanical behavior of sand-cement mixtures has undergone some controversies studied on the Chlef sand. In this paper, we present an experimental study to investigate the mechanical behavior of a sandy soil reinforced by a hydraulic binder (cement), using the direct shear apparatus emphasizing on the shear strength characteristics and the vertical deformation variation of cemented reinforced sand. The parameters used in this study are mainly: relative density (Dr = 80%), normal stress (σn = 100, 200, 400 kPa), water content (3, 7 and 10%), cement content (2.5, 5, 7.5 and 10 %) and cure time (7, 14 and 28 days). The experimental results show that the mechanical characteristics in terms of internal cohesion (C) and internal frication angle (φ) give a better mechanical performance with the binder inclusion, and the cure conditions play an effective role on the improvement of the shear strength. This result also showed that 10% of the cement content gave us a maximum value of shear strength and an optimal influence on the mechanical characteristics. The addition of cement not only improves the shear strength of soil, but also provides diversity in the resistance against the deformations imposed load, which can be established by a dilatant character.
Źródło:
Studia Geotechnica et Mechanica; 2019, 41, 4; 200-211
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies