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941.
Using digital image correlation, we track the displacement fluctuations within a persistent shear band in a dense sand specimen bounded by glass walls undergoing plane strain compression. The data evidences a clear, systematic, temporally recurring pattern of vortex formation, dissolution, and reformation throughout macroscopic softening and critical state regimes. During softening, locally affine deformation zones are observed at various locations along the shear band, which we argue to be kinematic signatures of semi-stable force chains. Force chain collapse then occurs, inducing vortex formation. Local jamming at the conflux of opposing displacements between adjacent vortices arrests the vortices, providing an avenue for potential new force chains to form amidst these jammed regions. The process repeats itself temporally throughout the critical state. The pattern further correlates with fluctuations in macroscopic shear stress. We characterize the nature of the observed vortices, as they are different in our sands comprised of irregular shaped particles, as compared to previous observations from experiments and numerical simulations which involved circular or rounded particles. The results provide an interesting benchmark for behavior of non-circular/non-spherical particles undergoing shear. 相似文献
942.
Lee Jihye Moon Sangmi Kwon Soonho Chu Myeonghun Bae Sara You Cheolwoo Liu Huaping Kim Jeong-Ho Kim Dae Jin Park Hosung Kim Jin Young Hwang Intae 《Wireless Personal Communications》2018,102(1):383-398
Wireless Personal Communications - Vehicle communication can facilitate efficient coordination among vehicles on the road and enable future vehicular applications such as vehicle safety... 相似文献
943.
Valeria Franchini Silvio Ceccuzzi Andrea Doria Gian Piero Gallerano Emilio Giovenale Gian Luca Ravera Andrea De Amicis Stefania De Sanctis Sara Di Cristofaro Elisa Regalbuto Elisa Coluzzi Jessica Marinaccio Antonella Sgura Roberto Bei Monica Benvenuto Andrea Modesti Laura Masuelli Florigio Lista 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(9):899-911
In this paper, we present a comprehensive discussion of the results obtained after in vitro exposure of human fetal fibroblasts and human adult fibroblasts to pulsed radiation in a wide band between 100 and 150 GHz and to continuous wave radiation at 25 GHz. In order to assess potential effects of exposure, the genome integrity, cell cycle, cytological ultrastructure, and proteins expression were evaluated. 相似文献
944.
Alireza Baghban Sara Zilabi Saeedeh Golrokhifar Sajjad Habibzadeh 《Petroleum Science and Technology》2018,36(4):326-331
The present contribution was performed in order to predict CO2 loading capacity in aqueous sodium glycinate as a novel class of green solution under wide operating range using radial basis function artificial neural network (RBFANN). The predicted CO2 loading capacity values were in brilliant agreement with those corresponding experimental values. The estimated values of MSE and R-squared were 0.00045 and 0.997, respectively. Accordingly, statistical and graphical analyses confirm satisfactory prediction of our proposed model. 相似文献
945.
An aspect of great relevance in Lead Fast Reactors (LFRs) is the actual void reactivity evaluation. The purpose of this work is double: to inquire into the physical problem, and to evaluate the impact of different approaches and numerical methods on the calculation of the critical reactor parameters involved. Thus, results concerning void effect contributors have been evaluated through a cross-checked analysis performed by means of both a deterministic and a stochastic code. The field of investigation that has been assumed consists in the reference configuration of the 600 MWe European Lead-cooled SYstem (ELSY), under development within the 6th and 7th EURATOM Framework Programmes. Calculations have been carried out on a 1500 MWth MOX-fuelled core, composed by wrapper-less square Fuel Assemblies (FAs) with pins on a square lattice. The ERANOS (European Reactor Analysis Optimized System) deterministic code ver. 2.1 and the MCNP Monte Carlo code ver. 4c have been employed in conjunction with the JEFF-3.1 nuclear data library to assess the void reactivity variation and its breakdown into the most relevant nuclides, using both the neutron balance equation method and perturbation theory. Results have shown a very good agreement between ERANOS and MCNP outcomes: the huge reactivity worth determined by the core active region voiding (approximately 5000 pcm) is due to the predominant contributions of even isotopes – among which 238U plays a major role, being responsible for roughly 4300 pcm – as a consequence of their fission cross-section high sensitivity to spectral hardening (threshold reactions), despite their modest contribution to the total fissions. 相似文献
946.
Sara Spilimbergo 《Journal of food engineering》2011,105(1):193-195
Non-thermal inactivation techniques in food industry are a major research issue, driven by an increased consumer demand for fresh and nutritious food products that are microbiologically safe, with a long shelf-life. Here we demonstrate for the first time the potential of pressurized N2O as a non-thermal inactivation processing aid for bacterial reduction in the pasteurization of raw fresh milk at mild operating conditions.Treatments were performed in a multi-batch apparatus at 12 MPa and at different temperature conditions (40-50 °C). Chemical parameters (pH, titratable acidity (TA)) of the untreated and treated samples were monitored and compared. Four independent experiments have been carried out at each operative condition (temperature, time, pressure).The study clearly demonstrates the great potentiality of the emerging technology: further development of the N2O process may open the doors to a new low temperature method for milk pasteurization, to be exploited on an industrial scale. 相似文献
947.
Morrison Elizabeth Wolfe; Wheeler-Smith Sara L.; Kamdar Dishan 《Canadian Metallurgical Quarterly》2011,96(1):183
Despite a growing body of research on employee voice—defined as the discretionary communication of ideas, suggestions, or opinions intended to improve organizational or unit functioning—the effects of shared or collective-level cognitions have received scant attention. There has also been relatively little research on voice within work groups. Our goal in this study was to address these important gaps by focusing on the effects of group-level beliefs about voice (i.e., group voice climate) on individual voice behavior within work groups. We conducted a cross-level investigation of voice behavior within 42 groups of engineers from a large chemical company. Consistent with our hypotheses, group voice climate was highly predictive of voice and explained variance beyond the effects of individual-level identification and satisfaction, and procedural justice climate. Also consistent with predictions, the effect of identification on voice was stronger in groups with favorable voice climates. These findings provide evidence that voice is shaped not just by individual attitudes and perceptions of the work context, as past research has shown, but also by group-level beliefs. The results also highlight the importance of broadening our conceptual models of voice to include shared cognitions and of conducting additional cross-level research on voice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
948.
Cast irons with some kinds of cementite with different chromium and vanadium contents were characterized.Fracture toughness was determined by using an indentation technique,along with microhardness and elastic modulus.The results show that at the load of 1N,microhardness of the cementite with 5.1% Cr is 10.53 GPa,the microhardness for cementite with 9.2% Cr increased to 11.25 GPa and for cementite with 4.5% V the microhardness is 9.18 GPa.The cementite with 9.2% Cr presented the highest elastic modulus of 230.4GPa and the cementite with 4% V presented the lowest value of 201.32 GPa.Cementite with 5.1% Cr presented higher fracture toughness than cementite with 9.2% Cr;however,cementite with 4.5% V presented the highest fracture toughness of2.74 MPa·m1/2 and the lowest brittleness index of 3.35μm-1/2. 相似文献
949.
Moeller Sara K.; Lee Elizabeth A. Ewing; Robinson Michael D. 《Canadian Metallurgical Quarterly》2011,11(4):816
Dominance and submission constitute fundamentally different social interaction strategies that may be enacted most effectively to the extent that the emotions of others are relatively ignored (dominance) versus noticed (submission). On the basis of such considerations, we hypothesized a systematic relationship between chronic tendencies toward high versus low levels of interpersonal dominance and emotion decoding accuracy in objective tasks. In two studies (total N = 232), interpersonally dominant individuals exhibited poorer levels of emotion recognition in response to audio and video clips (Study 1) and facial expressions of emotion (Study 2). The results provide a novel perspective on interpersonal dominance, suggest its strategic nature (Study 2), and are discussed in relation to Fiske's (1993) social–cognitive theory of power. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
950.