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521.
522.
K. Jindal D. Bhattacharya L.F. Francis A.V. McCormick L.T. Germinario C. Williams 《Progress in Organic Coatings》2010
A model volatile organic compound (VOC) compliant two component (2K) acrylic polyol refinish clearcoat was prepared and used to study the effects of a cellulose-based additive on drying, curing, rheology and stress development at room temperature. Results were compared with commercially available VOC compliant and traditional non-compliant clearcoats. Most of the drying of the low VOC coatings occurred before appreciable (20%) crosslinking. Tensile stress developed in the same timeframe as drying and then relaxed over a longer time scale. All coatings had relatively low levels of peak stress (<0.25 MPa) compared to other polymer coatings. Model low VOC coatings prepared with the additive had higher peak stresses than those without the additive. In addition, rheological data showed that the additive resulted in greater viscosity buildup after application. Both effects are attributed to the high glass transition temperature of the additive (∼70 °C). 相似文献
523.
Akhilesh K. Gaharwar Patrick Schexnailder Vikas Kaul Ozan Akkus Dmitri Zakharov Soenke Seifert Gudrun Schmidt 《Advanced functional materials》2010,20(3):429-436
The structure and mechanical properties of bio‐nanocomposite films made from poly(ethylene oxide) (PEO) that is physically cross‐linked with silicate nanoparticles, Laponite, are investigated. Direction‐dependent mechanical properties of the films are presented, and the effect of shear orientation during sample preparation on tensile strength and elongation is assessed. Repeated mechanical deformation results in highly extensible materials with preferred orientation and structuring at the nano‐ and micrometer scales. Additionally, in vitro biocompatibility data are reported, and NIH 3T3 fibroblasts are observed to readily adhere and proliferate on silicate cross‐linked PEO while maintaining high cell viability. 相似文献
524.
Assist. Prof. Somnath Lahiri Assoc. Prof. Vikas Kumar 《Management International Review》2012,52(3):317-340
- This study measures and ranks the productivity of academic institutions and faculty members based on the number of publications appearing in the top three core international business journals between 2001 and 2009.
- This research serves as a useful update and extension of studies by Morrison and Inkpen (1991), Inkpen and Beamish (1994), and Kumar and Kundu (2004), which examined the top three international business journals, namely,Management International Review,Journal of International Business Studies, andJournal of World Business.
- Copenhagen Business School, University of Miami, and University of Leeds (among institutions), and Yadong Luo, Peter J. Buckley, and Alain Verbeke (among authors) occupy the top three positions.
525.
On the use of damped updated FE model for dynamic design 总被引:1,自引:0,他引:1
Model updating techniques are used to update the finite element model of a structure, so that updated model predicts the dynamics of a structure more accurately. The application of such an updated model in dynamic design demands that it also predicts the effects of structural modifications with a reasonable accuracy. Most of the model updating techniques neglect damping and so these updated models cannot be used for predicting amplitudes of vibration at resonance and antiresonance frequencies. This paper deals with updating of the finite element model using the FRF data with damping identification using complex modal data and its subsequent use for predicting the effects of structure modifications. The updated model is obtained in two steps. In the first step, mass and stiffness matrices are updated using FRF-based model updating method. In the second step, damping is identified using updated mass and stiffness matrices, which are obtained in first step. Structural modifications in terms of mass and beam modifications are then introduced to evaluate the updated model for its usefulness in dynamic design. 相似文献
526.
Previously, thermal rectification has been reported in several low-dimensional shape-asymmetric nanomaterials. In this Letter, we demonstrate that a three-dimensional crystalline material with an asymmetric shape also displays as strong thermal rectification as low-dimensional materials do. The observed rectification is attributed to the stronger temperature dependence of vibration density of states in the narrower region of the asymmetric material, resulting from the small number of atomic degrees of freedom directly interacting with the thermostat. We also demonstrate that the often reported "device shape asymmetry" is not a sufficient condition for thermal rectification. Specifically, the size asymmetry in boundary thermal contacts is equally important toward determining the magnitude of thermal rectification. When the boundary thermal contacts retain the same size asymmetry as the nanomaterial, the overall system displays notable thermal rectification, in accordance with existing literature. However, when the wider region of the asymmetric nanomaterial is partially thermostatted by a smaller sized contact, thermal rectification decreases dramatically and even changes direction. 相似文献
527.
New and alternative oil crops must be explored for extending the horizon of plant based fuels for the increasing number of engines in agriculture sector. To preserve the biodiversity, locally available oil crops need to be identified and evaluated for its biodiesel potential. In this study, one of such oil crop, i.e., Hibiscus cannabinus (Ambadi) was selected for exploring the potential to be used as alternative fuel in diesel engines. The oil is found to be good as the properties of its methyl ester (biodiesel) are well within the range prescribed by ASTM. The biodiesel so prepared posses 8% lesser heat content when compared to diesel on volume basis but thermal efficiency and specific fuel consumption improves with blend of 20% (B20). Improved combustion regimes are also seen with the biodiesel blends. 相似文献
528.
Jindal Swati Sivia Jagtar Singh Bindra Harminder Singh 《Wireless Personal Communications》2019,109(3):1471-1490
Wireless Personal Communications - This paper describes a novel design of Minkowski and Meander curves based hybrid fractal antenna for mobile devices used for communication in delay tolerant... 相似文献
529.
IM-ELPR: Influence maximization in social networks using label propagation based community structure
Kumar Sanjay Singhla Lakshay Jindal Kshitij Grover Khyati Panda B. S. 《Applied Intelligence》2021,51(11):7647-7665
Applied Intelligence - The popularity of social networks has grown manifolds in recent years because of various activities like fast propagation of ideas, publicity, and news. Influence... 相似文献
530.
Wireless Personal Communications - In this work, a three-hop wireless relaying model comprising of a single source and destination node, along with two relay nodes and an eavesdropper is... 相似文献