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71.
In this paper, we study information cascade in networks with positive and negative edges. The cascade depth is correlated with community structure of signed networks where communities are defined such that positive inter-community and negative intra-community links are minimized. The cascade is initialized from a number of nodes that are selected randomly. Finally, the number of nodes that have participated in the cascade is interpreted as cascade depth; the more the number of such nodes, the more the depth of the cascade. We investigate influence of community structure (i.e., percentage of inter-community positive and intra-community negative links) on the cascade depth. We find significant influence of community structure on cascade depth in both model and real networks. Our results show that the more the intra-community negative links (i.e., the worse the community structure), the more the cascade depth. 相似文献
72.
Mehdi Sharif Behzad Pourabbas Marco Sangermano Farjam Sadeghi Moghadam Mahsa Mohammadi Ignazio Roppolo Ali Fazli 《Polymer International》2017,66(3):405-417
In the present study SU8 nanocomposites were prepared by incorporating graphene oxide (GO ), and its effect on the UV curing kinetics, morphology, electrical, hardness and thermal properties of the nanocomposites were investigated at different loading levels of GO (0.1 ? 3 wt%). Studying the reaction kinetics of the UV curing process by means of real‐time infrared spectroscopy showed that the polymerization rate and the final conversion of epoxy groups was related to the loading level of GO in the nanocomposites. An autocatalytic kinetics model of the curing reaction confirmed the effect of GO nanoparticles on the curing rate constant (k ), the order of the initiation reaction (m ) and the ultimate conversion of the UV ‐cured nanocomposites. Appropriate experimental observations indicated that dispersion of GO within the resin plays a critical role on the cure kinetics and final conversion. The results of the kinetics modeling and morphological observations showed that the curing rate constant of the nanocomposites is highly dependent on the GO content and its dispersion state, indicating that GO prevents epoxy resin crosslinking by photoinitator deactivation. Moreover, oxygen functionalities, such as hydroxyl and carboxyl groups, on the surface of GO facilitate interfacial interactions between epoxy groups from the matrix and GO . Electrical conductivity measurements demonstrated that the UV ‐induced photo‐cured GO filled resins are conductive SU8 nanocomposites. It was observed that the thermal stability of the nanocomposites is enhanced due to the dispersion of GO in the matrix. Moreover, the microhardness analysis showed that addition of GO to neat SU8 increases the mechanical hardness of the nanocomposite. © 2016 Society of Chemical Industry 相似文献
73.
Kaveh Mahsa Mirzabeigi Mahdieh Sotudeh Hajar Moloodi Amirsaeid 《Scientometrics》2022,127(2):1099-1128
Scientometrics - The objective of this study was to examine the effects of the challenges in the transliteration of Persian names into English on the recall of retrieved results in the Web of... 相似文献
74.
Composite polyvinyl amine/SBA-15 (PVAm/SBA-15) in various amounts of SBA-15 were prepared and characterized. The physical and chemical properties of PVAm/SBA-15 were investigated using FT-IR, XRD, BET, SEM and TGA techniques. The catalytic performance of each material was determined for the Knoevenagel condensation reaction between carbonyl compounds and ethyl cyanoacetate in the presence of ethanol as solvent. The effects of reaction temperature, solvent and the amounts of catalyst as well as recyclability of the catalyst were investigated. The catalyst used for this synthetically useful transformation showed a considerable degree of reusability besides being very active. 相似文献
75.
Microsystem Technologies - In this present work the critical loading of magneto-electro-viscoelastic-hygro-thermal (MEVHT) piezoelectric nanoplates embedded in a viscoelastic foundation are... 相似文献
76.
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78.
Mahsa Naghshineh Abdul Azis Ariffin Hasanah Mohd Ghazali Hamed Mirhosseini Abdulkarim S. Mohammad 《Journal of the American Oil Chemists' Society》2010,87(3):255-262
Although blending polyunsaturated oil with more saturated or monounsaturated oils has been studied extensively, there is no
similar information regarding the partial replacement of palm olein with olive oil (OO). Therefore the main objective of this
study was to investigate the effects of OO partial replacement (0, 25, 50, 75, 90 and 100% w/w) on the chemical stability
of palm olein oil (POO). The physicochemical properties of oil samples namely iodine value, peroxide value (PV), anisidine
value, TOTOX value (total oxidation value, TV), free fatty acid (FFA), cloud point, color and viscosity were considered as
response variables. Significant differences among the oil blend properties were determined at the significance level of P < 0.05. Apart from FFA, all the response variables were significantly influenced by type and concentration of oils. The oil
blend containing 10% POO and 90% OO showed the highest TV (6.10); whereas the blend containing 90% POO and 10% OO exhibited
the least TV (2.41). This study indicated that the chemical stability of oil blend significantly (P < 0.05) increased with increasing the proportion of polyunsaturated/monounsaturated fatty acid. 相似文献
79.
Mohammad Shariyat Mahsa Rahimi‐Ghozat 《Fatigue & Fracture of Engineering Materials & Structures》2020,43(3):466-487
Two frameworks are employed to develop two distinct categories of multiaxial high cycle fatigue life assessment models for composite components experiencing general and random loading conditions. In this regard, the decay in the material properties with cycles is also taken into account. It is obvious that in multilayer components, the fatigue failure is a progressive process that may be accompanied by gradual or sudden changes in the material properties and, consequently, the resulting stresses. In addition to using the traditional progressive damage analyses, a new concept is proposed for tracing of the localized fatigue failures more accurately. It is postulated that generally, the stress components have distinct frequencies, phase shifts, and mean values that all vary with time in a random manner. The proposed fatigue criteria, especially, the equivalent‐stress–based ones, are capable of predicting various fatigue failure modes, such as the fibre breakage, matrix cracking, and interfacial debonding. A special and comprehensive fatigue failure tracking and cycle counting algorithms that are capable of handling the mentioned general peculiarities are proposed. The proposed HCF criteria and the relevant fatigue life assessment algorithm are then implemented on a composite multilayer mono‐leaf spring of a realistic vehicle under a random field‐measured loading condition, as a typical component, and the results are compared and the experimental results conducted by the authors, for accuracy investigations. The considered stochastic road inputs have been chosen on the basis of the consumption times and field measurements. 相似文献
80.
The effect of the neonatal thymus grafting or "Thymostimulin" administration on the cellularity, cell composition, immune, response to SRBC and proliferative activity of T- and B-cells in vitro were determined in neonatal spleen grafted CBA/Ca female mice of different ages. Analysis of the thymus graft effect on the T- and B-cells content in the spleen transplant from the adult and old recipients demonstrated no differences. The neonatal thymus grafting led to the essential increase of the immune response, spleen cellularity and to the diametrically opposed changing from negative to positive of the sign of the correlation coefficient between the T-cells content and the cellularity of the neonatal spleen in the old recipients. The similar effect of the neonatal thymus grafting was revealed in respect of correlative connection between content of the T-cells and PFCs in spleen grafted to the old recipients too. The "Thymostimulin" injection led only to the increase of the spleen transplant cellularity. These results suggests that the young thymic microenvironment is essential for the normal T-cells differentiation and for its normal function in the neonatal spleen transplant. 相似文献