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排序方式: 共有3016条查询结果,搜索用时 15 毫秒
971.
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
972.
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
973.
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
974.
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
975.
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
976.
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
977.
Sara Pascale Elisa Scatena Filippo Fabbri 《Fullerenes, Nanotubes and Carbon Nanostructures》2017,25(10):585-588
Boron carbide B12C3 microcrystals were neutron irradiated at four different fluences, namely at 1.09, 2.19, 3.28 and 4.38 × 1016 n cm?2. The structural properties were studied by means of Raman spectroscopy, revealing that the neutron induced structural defects are focused toward the interstitial chains of B12C3. The morphology of the B12C3 samples was studied by means of secondary electron imaging showing that the neutron irradiation did not modify the size distribution of the microcrystals. 相似文献
978.
Murat Subaşı Sıdıka Şule Şener Yeşim Saraç 《Computers & Mathematics with Applications》2011,61(9):2854-2862
In this paper, we apply the Galerkin method to the problem of vibration of a one-dimensional system with free end conditions. Giving a MAPLE®procedure, we test the results on two numerical examples. 相似文献
979.
Paolo Basso Sara Casciati Lucia Faravelli 《Structure and Infrastructure Engineering》2015,11(1):27-37
The evolution of the railway traffic during the last century is studied as preliminary step towards the estimation of the remaining service life of a historical bridge. The selected case study concerns the El Ourit Bridge, designed in 1889 by Gustave Eiffel and located close to the town of Tlemcen, in Algeria. A finite element model of the structure is built and the response of the bridge to train-crossing loads is numerically evaluated with the purpose of identifying the element most affected by stress variations. The Palmgren–Miner accumulation model is used to quantify the fatigue damage in this element. A limit state function based on this criterion is formulated; then, a fully probabilistic approach is adopted by assuming that the stress amplitude, the fatigue strength and the damage threshold value play the role of random variables. The obtained results are discussed in order to evaluate the residual service life of the bridge. 相似文献
980.
Quality of service analysis and improvement with cross layer power allocation in multirelay networks
Quality of service (QoS) guarantee is the main performance metric for designing future wireless networks. For real time applications over wireless links, statistical delay QoS guarantee is the most important QoS metrics. The main goal of this paper is studying the effects of multi‐decode‐and‐forward‐relaying transmission on delay QoS guarantee and user satisfaction. For this end, we first propose an approach to simplify the analysis of statistical delay QoS guarantee by the use of a curve named QoS analysis curve. The QoS analysis curve of any system is based on its effective capacity (EC) function. So, we derive a closed‐form expression for the EC function of a multi‐decode‐and‐forward‐relay network to reduce the computational complexity of finding this quantity. After that, for improving the QoS guarantee performance of a multi‐decode‐and‐forward‐relaying system, the EC of the system is maximized by the use of power allocation (PA) technique. At first, an adaptive PA (APA) algorithm is proposed in which the source and relays PA policies are derived analytically. Although, the overhead of this algorithm is large, it significantly improves the statistical delay QoS guarantee performance. Then, for the systems that cannot tolerate the required large overhead of APA, a fixed PA scheme is presented, which is based on particle swarm optimization algorithm. There is a tradeoff between providing the delay QoS guarantee and the required overhead, in selecting APA or fixed PA schemes. The numerical results validate our analytical outcomes and evaluate our proposed algorithms. 相似文献