Search Options

Sort by:

Sort search results by

Publication Type:

Publication Type filter

Open access:

Publication Date:

Periodicals:

Periodicals filter

Search results

Online since: January 2012
Authors: Ying Xian Zhao, Sheng Jian Zhang
Moschopedis et al. [6] determined the molecular weight of asphaltenes with vapor-pressure osmometry; Syunyaev and Balabin [7] studied the polarization of asphaltene by Fluorescence; Trejo et al [8] characterized asphaltenes using SEC, LDMS, MALDI, NMR and XRD; and Speight et al. [9] suggested that asphaltenes had several types of structures rather than a definitive molecular structure.
For thermal cracking of asphaltene, Wiehe [16] obtained a first-order kinetic rate constant of 0.026 min-1 for conversion of Cold Lake asphaltenes at 673 K, whereas Martinez et al. [17] presented an interesting three-lump kinetic analysis on thermal cracking of an asphaltenic residue in temperature range 698 to 748 K and gave a second-order kinetics throughout for asphaltene conversion and oil+gas and coke formation; for non-catalytic hydrocracking of asphaltene process, Zhao et al. [18] reported the first-order activation energy of 176 kJ/mol for cracking of Athabasca asphaltenes in temperature range 623 to 703 K; for catalytic hydrocracking process, Usui et al [19] investigated hydrocracking reactivities of two pentane-insoluble asphaltene samples over Pd-Ni/NH4-Y zeolite, but did not give the quantitative analysis of the details of reaction kinetics.
Assuming that hydrogen consumption is negligible as compared with its original amount, then the overall reaction of asphaltene can be simplified in terms of lumped liquid, gas, and solid (coke) products as (2) where PL , PG and PS represent the liquid, gas and solid (coke) products, and aL, aG and aS are their stoichiometric coefficients, respectively.
[5] E.L.
Online since: June 2020
Authors: Ahmed W. Abdelghany, Sally Elkatatny, Mohamed Abdel Hady Gepreel
Elkatatny et al. [4, 5] introduced new non-equiatomic low-cost HEAs by using thermodynamic principles to achieve a high cold workable and high strength.
Two new alloys were introduced, namely Al(5,10)Cr12Mn(28,23)Fe35Ni20 where Al (5 and 10 at%, respectively) was increased at the expense of Mn (28, 23 at%) and FCC structure was maintained.
Changes in the thermodynamic parameters due to substituting Mn with Al to these HEAs enhanced their mechanical properties.
The experimental results were compared with the previous above-mentioned studied alloys by Elkatatny et al [4, 5].
Chiba: Effect of Al content and cold rolling on the microstructure and mechanical properties of Al5Cr12Fe35Mn28Ni20 high-entropy alloy, Mater.
Online since: September 2013
Authors: Qi Peng Cai, Yun Huang, Fan Yan Meng
Cole and Lade [2] proposed a theoretical model for predicting the location of a failure surface in sand overlying a dip slip fault Anastasopoulos et al. [3] and Anastasopoulos et al. [4] developed a semi-empirical approach for the analysis of dip-slip fault rupture propagation.Although these theoretical models provide insights into the behavior of fault rupture in sand, settlement profiles in depth cannot be evaluated using these methods.
Normalization issues of subsurface settlement profiles Anastasopoulos et al. [13] reported measured surface displacements induced by normal faulting at 60o in sand with a thickness of 25 m (Test 4), as shown in Fig.3(a).
To verify the validity of the normalization suggested in this study, the centrifuge test results reported by Anastasopoulos et al. [13] were reviewed.
R., and El Nahas, A. .Fault rupture propagation through sand: Finite-element analysis and validation through centrifuge experiments[J].
Online since: April 2015
Authors: S.A. Osman, Ibrahim H. Alfahdawi
Although many research works have been carried out by Al-Mahaidi et al. [3], Soudki et al. [4], Smith and Teng [5], and Taljsten [6] on shear strengthening of RC beams with CFRP but flexure strengthening study has been rather limited especially the numerical modelling approach.
[3] Al-Mahaidi R., Lee K. and Susa J.
[4] Soudki K., El-Salakawy E. and Craig B.
Online since: May 2013
Authors: Ibrahim Sipan, Aminu Umar, Alkali Ibrahim Abubakar, Usman Bukar Wakawa, Maimunah Sapri, Suleiman Aliyu Shika
Ascioneet al; asserts that, Simulation tools represent continuous, stochastic processes in buildings by discrete time-step, deterministic model estimations [1], hence in their study ‘Energy retrofit of historical buildings: theoretical and experimental investigations for the modelling of reliable performance scenarios’ it was reported that; the possible finding of real historical consumptions and of numerous information related to the energy absorptions of the different installed devices concurred to an accurate modelling of the numerical instruments for the building dynamic energy simulation.
The building modelling has been realized using many known data, relatively to: • The kind of building uses; • The thermal–physical characterization of the building structures • The occupancy scheduling and uses of the active energy systems However, according toRaftery et al[4] there are issues with calibrated simulation today.
Contrasting the properties of current and proposed approaches to calibrated simulation Adapted from Ascioneet al, (2011).
[2] Olsen, E.L. and Chen, Q.
[15] Iqbal, I and Al-Homoud, M.S.
Online since: June 2007
Authors: Ki Bae Kim, Jae Ho Han, Sang Whan Park, Jayamani Jayaraj, Eric Fleury
Recently, nano-laminated single phase Cr2AlC bulk material was successfully prepared by hot pressing of CrCx and Al powder mixture [6].
Experimental procedure Bulk Cr2AlC ternary carbide was synthesized by a hot pressing of Al and Cr3C2 and Cr7C3 (later referred as CrCx) powder mixture of size < 45 μm, under 25 MPa at 1200 oC for 1 hr in an Ar atmosphere [6].
The corrosion behavior of the Cr2AlC ternary carbide plates was studied by electrochemical measurements in a simulated aggressive PEMFC environment; all the experiments were conducted in 1M H2SO4 + 2 ppm −F at 80 oC [8] under either hydrogen gas or pressurized air bubbled into the solution throughout the experiments to simulate the respective anodic and cathodic PEMFC environments, as described by Jayaraj et al. [5]. 3.
SEM microstructure of Cr2AlC Fig.2.Contact resistance of graphite, stainless specimen synthesized by hot pressing at steel and Cr2AlC ternary carbide alloy measured 1200 o C of CrCx and Al powder mixture.
El-Raghy, J.
Online since: September 2007
Authors: Gabriel Ferro, Gerhard Pensl, Kin Kiong Lee, Maher Soueidan
For instance, Lee et al
Recently, Soueidan et al. [4] have successfully grow high quality singledomain 3C-SiC films on 6H-SiC substrates by the Vapour-Liquid-Solid mechanism.
Close to the conduction band-edge of 4H-SiC, an intrinsic defect located in the SiO2 was proposed by Afanasev' et al. [7], who found that these defects are energetically localized at Ec(SiO2) - 2.77 eV in the oxide.
Afanasev' et al. [8] also suggested that carbon clusters of different sizes are responsible for the interface states observed in the lower part of the bandgap, whereby the onset of filled carbon states is located at EV+ 1.4 eV.
El-Sayed, G.
Online since: November 2010
Authors: Xiao Chun Zhou, Xiao Jun Wang
Harshe et al.: Mater.
Kulkarni et al.: Mater.
Sombra et al.: J.
Yu et al.: J.
Kingslay and E.L.
Online since: August 2013
Authors: Yue Rong Lei, Jian Ling Chen, Xu Zhan, Hui Ming Zeng, Ling Yan Du
Ke et al also proposed a scheme for restoration of tampered image [8].
Ho et al proposed a ztransformed based scheme to authenticate digital image in pixel level [9].
Xiao et al [10] proposed an improvement of the semi fragile method proposed in [2].
Zou et al [11] and Coelho et el [12] proposed integer wavelet transform based image authentication scheme.
Online since: April 2014
Authors: Fu Min Chu, Yuan Sheng Yang, Jin Wei Wang, Ji Xue Zhou, Shou Qiu Tang
The 0.2% yield strength (YS), ultimate tensile strength (UTS) and elongation (EL) to rupture were all averaged over three specimens.
Table 1 Chemical composition of AS31 ingot (wt.%) Element Al Si Mn Be Cu Fe Ni Mg Content 3.10 0.91 0.17 0.0014 0.0049 0.0011 0.0003 Balance Results and discussion As cast microstructure.
Pan: China Foundry Vol.6 (2009), p. 37 [12] Cong M, Li Z, Liu J, et al: Materials & Design, 2014, 53: 430-434
[14]Fan C H, Chen Z H, He W Q, et al: Journal of Alloys and Compounds, 2010, 504(2): L42-L45
[15]Fischer S F, Schüler P, Fleck C, et al: Acta Materialia, 2013, 61(14): 5152-5161.
Showing 3671 to 3680 of 9913 items