Purpose: This study was undertaken to investigate the rheological properties of inter-granular material bridges on the nano-scale when strained at high shear rates.
Materials And Methods: Atomic force microscopy (AFM) was used as a rheometer to measure the viscoelasticity of inter-granular material bridges for lactose:PVP K29/32 and lactose:PVP K90 granules, produced by wet granulation.
Results: The loss tangent (tan delta) and both the storage (G') and loss shear moduli (G'') of inter-granular material bridges were measured as a function of the probe-sample separation distance, oscillation frequency and relative humidity (RH). As the probe was withdrawn from the granule surface tan delta initially increased rapidly from zero to a plateau phase. G'' became increasingly dominant as the bridge was further extended and eventually exceeded G'. At high RH, capillary forces were foremost at bridge rupture, whereas at low RH elastic forces dominated. The effect of increasing frequency was to increase the effective elasticity of the bridge at high RH.
Conclusions: AFM has been employed as a rheometer to investigate the nano-scale rheology of inter-granular material bridges. This novel method may be used to obtain a fundamental understanding how different binders, granulated with different diluent fillers, behave at high shear rates.
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http://dx.doi.org/10.1007/s11095-009-9828-z | DOI Listing |
Adv Sci (Weinh)
November 2024
Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, 610064, China.
Heliyon
August 2024
Department of Industrial Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh, 11421, Saudi Arabia.
Dissimilar metal combinations are frequently employed in the power generation and nuclear industries. Where stainless steel piping systems are connected to pressure vessels made of low-alloy steel, the subsystems of liquid rocket engines also have different, dissimilar material combinations. Dissimilar welding plays a vital role in ensuring the integrity, performance, and reliability of components and structures operating in cryogenic environments, in this study, plates of AISI 316L and AISI 321, each 5 mm thick, were successfully joined using the pulsed current gas tungsten arc welding (PCGTAW) technique with optimized process parameters.
View Article and Find Full Text PDFNanoscale Adv
September 2023
Department of Engineering Physics, Polytechnique Montréal C.P. 6079, Succ. Centre-Ville Montréal QC H3C3A7 Canada
Eumelanin, the brown-black member of the melanin biopigment family, is a prototype material for sustainable (green) organic electronics. Sepia eumelanin (Sepia) is a type of biosourced eumelanin extracted from the ink sac of cuttlefish. Electron microscopy and scanning probe microscopy images of Sepia show distinguishable near spherical granules with diameters of about 150-200 nm.
View Article and Find Full Text PDFWaste Manag
October 2023
School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China; Key Laboratory for Energy Beam Metallurgy and Advanced Materials Preparation of Liaoning Province, Dalian, 116024, China. Electronic address:
Photovoltaic solid waste, particularly diamond-wire sawing silicon powder (DWSSP), has emerged as a significant concern in the industry. Consequently, the recycling and reuse of such waste have become a prominent research focus. In this study, focusing on achieving direct recycling and reuse of DWSSP, the key driving factors for effective purification were identified.
View Article and Find Full Text PDFMaterials (Basel)
June 2023
Key Laboratory of Advanced Manufacturing and Intelligent Technology (Ministry of Education), School of Material Science and Chemical Engineering, Harbin University of Science and Technology, Harbin 150000, China.
Strengthening Mg alloys with rare earth elements has been a research focus for several decades. To minimize the usage of rare earth elements while enhancing mechanical properties, we adopted the strategy of alloying with multiple rare earth elements, namely Gd, Y, Nd, and Sm. Additionally, to promote the precipitation of basal precipitate, Ag and Zn doping was also induced.
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