Effect of Process Parameters of CNT Containing Friction Powder on Flexural Properties and Friction Performance of Organic Brake Friction Materials

This research is to investigate the influences of carbon nanotube (CNT) containing friction powder prepared through different process parameters on flexural properties and friction performance of organic brake friction materials. Experimental results indicate significant influence on flexural property and friction performance of organic brake friction materials when the modified CNT/friction powders are adopted. Particularly for the specimens adopted the modified CNT/friction powders prepared through 2.0 M concentration of catalyst and 30% C2H2 show the highest flexural strength, better ductility and toughness, most stable friction coefficient, and lowest weight loss. However, too many amorphous carbon clusters and CNTs aggregation derived from higher concentration of catalyst and ratio of C2H2/N2 would cause poor formation of specimens and reduction of reinforcement effectiveness

A first update on mapping the human genetic architecture of COVID-19

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Annealing-Driven Microstructural Evolution and Its Effects on the Surface and Nanomechanical Properties of Cu-Doped NiO Thin Films

The effects of annealing temperature on the structural, surface morphological and nanomechanical properties of Cu-doped (Cu-10 at %) NiO thin films grown on glass substrates by radio-frequency magnetron sputtering are investigated in this study. The X-ray diffraction (XRD) results indicated that the as-deposited Cu-doped NiO (CNO) thin films predominantly consisted of highly defective (200)-oriented grains, as revealed by the broadened diffraction peaks. Progressively increasing the annealing temperature from 300 to 500 °C appeared to drive the films into a more equiaxed polycrystalline structure with enhanced film crystallinity, as manifested by the increased intensities and narrower peak widths of (111), (200) and even (220) diffraction peaks. The changes in the film microstructure appeared to result in significant effects on the surface energy, in particular the wettability of the films as revealed by the X-ray photoelectron spectroscopy and the contact angle of the water droplets on the film surface. The nanoindentation tests further revealed that both the hardness and Young’s modulus of the CNO thin films increased with the annealing temperature, suggesting that the strain state and/or grain boundaries may have played a prominent role in determining the film’s nanomechanical characterizations

Phase transformation behavior of 3 mol% yttria partially-stabilized ZrO2 (3Y–PSZ) precursor powder by an isothermal method

The phase transformation behavior of freeze-dried 3 mol% yttria–partially-stabilized zirconia (3Y–PSZ) precursor powder has been studied. When the freeze-dried 3Y–PSZ precursor powder was calcined at 773–1073 K for 2 h, the crystalline structure was composed of tetragonal and monoclinic ZrO2 as primary and secondary phases, respectively. The freeze-dried 3Y–PSZ precursor powder after calcination at 773 K, the monoclinic ZrO2 content abruptly increased from 8.00% to 31.51% and the tetragonal ZrO2 content suddenly decreased from 92.00% to 68.49%, with the duration increasing from 0.5 to 1 min. The activation energy of the isothermal transformation from tetragonal to monoclinic was 7.02 kJ/mol. The kinetics equation for the phase transformation from tetragonal to monoclinic in the freeze-dried 3Y–PSZ precursor powder between 773 K and 1273 K for various durations is described as ln(1/1−α)=1/2.61[t2.61(1.50×10−3)2.61exp(−7.02×310/RT)]; whereas, the HRTEM image shows a typical monoclinic ZrO2 domain because of the stress-induced tetragonal to monoclinic ZrO2 martensitic transformation that has occurred

ILC Reference Design Report Volume 1 - Executive Summary

The International Linear Collider (ILC) is a 200-500 GeV center-of-mass high-luminosity linear electron-positron collider, based on 1.3 GHz superconducting radio-frequency (SCRF) accelerating cavities. The ILC has a total footprint of about 31 km and is designed for a peak luminosity of 2x10^34 cm^-2s^-1. This report is the Executive Summary (Volume I) of the four volume Reference Design Report. It gives an overview of the physics at the ILC, the accelerator design and value estimate, the detector concepts, and the next steps towards project realization.The International Linear Collider (ILC) is a 200-500 GeV center-of-mass high-luminosity linear electron-positron collider, based on 1.3 GHz superconducting radio-frequency (SCRF) accelerating cavities. The ILC has a total footprint of about 31 km and is designed for a peak luminosity of 2x10^34 cm^-2s^-1. This report is the Executive Summary (Volume I) of the four volume Reference Design Report. It gives an overview of the physics at the ILC, the accelerator design and value estimate, the detector concepts, and the next steps towards project realization