Microscopic Phase Structure of Mo-based Catalyst and Its Catalytic Activity for Soot Oxidation

The MoO3 catalysts supported on nano-scale TiO2 with various loading rates (5%, 10%, 20%, and 40%) were prepared by an impregnation method. The phase structures of nano-scale MoO3/TiO2 catalysts were characterized by Brunner-Emmet-Teller, Fourier Transform Infrared Spectra, X-ray Diffraction, and Scanning Electron Microscope. The oxidation activities of catalysts over diesel soot were performed in a Thermogravimetric Analysis system. The kinetics of the catalytic oxidation process was analyzed based on Starink method. The characterization results showed that the phase structure of MoO3 supported on TiO2 depends heavily on the molybdenum contents, which put great effects on soot oxidation. The orthorhombic crystal system (α-MoO3) appeared on the surface of the catalysts when the MoO3 exceeds 10%. Due to the low melting point and good surface mobility of MoO3, the catalytic activity was increased and the characteristic temperatures were decreased with the increase in MoO3 contents. As a result, the activities of catalysts with different loading rates for soot oxidation can be ranked as: Mo5<Mo10<Mo2

Optimized Heating Rate and Soot-catalyst Ratio for Soot Oxidation over MoO3 Catalyst

MoO3 is now utilized as a promising catalyst due to its high activity and favorable mobility at low temperature. Its spectral data and surface microstructures were characterized by Fourier transform infrared spectra (FT-IR) and Field emission scanning electron microscope (FESEM). Thermo-analysis of the carbon black was performed over nano-MoO3 catalyst in a thermogravimetric analyzer (TGA) at various heating rates and soot-catalyst ratios. Through the analysis of kinetic parameters, we found that the heat transfer effect and diffusion effect can be removed by setting lower heating rates and soot-catalyst ratios. Therefore, a strategy for selecting proper thermogravimetric parameters were established, which can contribute to the better understanding of thermo-analytical process.

Optimized Heating Rate and Soot-catalyst Ratio for Soot Oxidation over MoO3 Catalyst

MoO3 is now utilized as a promising catalyst due to its high activity and favorable mobility at low temperature. Its spectral data and surface microstructures were characterized by Fourier transform infrared spectra (FT-IR) and Field emission scanning electron microscope (FESEM). Thermo-analysis of the carbon black was performed over nano-MoO3 catalyst in a thermogravimetric analyzer (TGA) at various heating rates and soot-catalyst ratios. Through the analysis of kinetic parameters, we found that the heat transfer effect and diffusion effect can be removed by setting lower heating rates and soot-catalyst ratios. Therefore, a strategy for selecting proper thermogravimetric parameters were established, which can contribute to the better understanding of thermo-analytical process. Copyright © 2017 BCREC Group. All rights reserved Received: 4th December 2016; Revised: 13rd June 2017; Accepted: 9th April 2017; Available online: 27th October 2017; Published regularly: December 2017 How to Cite: Mei, C., Mei, D., Yue, S, Chen, Z., Yuan, Y. (2017). Optimized Heating Rate and Soot-catalyst Ratio for Soot Oxidation over MoO3 Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (3): 408-414 (doi:10.9767/bcrec.12.3.845.408-41

Phy-chemical Attributes of Nano-scale V2O5/TiO2 Catalyst and Its’ Effect on Soot Oxidation

The V2O5 catalysts which supported on nano-scale TiO2 with variation of vanadium contents (5%, 10%, 20% and 40%) were prepared by an incipient-wetness impregnation method. The phase structures of nano-scale V2O5/TiO2 catalysts with different loading rates were characterized by Scanning electron microscope (SEM), X-Ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectra. The oxidation activities of catalysts over diesel soot were performed in a themogravimetric analysis (TGA) system. The kinetics of the catalytic oxidation process were analyzed based on Flynn-Wall-Ozawa method. The characterization results showed that the phase structure of V2O5 supported on TiO2 depends heavily on the vanadium contents, which will put great effects on the catalytic performances for soot oxidation. At a low vanadium loading rates (V5-V20), active species exist as monomers and polymeric states. At a high loading rate (V40), the crystalline bulk V2O5 covers the surface of TiO2. The formed crystal structure occupied the active sites and led a decreasing in the catalytic effect. By comparing the characteristics temperatures of soot oxidation over V2O5 catalysts, the catalytic activities of catalysts with different loading rates for soot oxidation can be ranked as: V5 < V10 < V40 < V20. Via pyrolysis kinetics analysis, it is revealed that the activation energy of soot oxidation is minimum when the vanadium loading rates is 20%, which is fit well with the TG experimental results. The consistency of pyrolysis kinetics and TG experimental results confirm that the best activity catalyst is V20 in discussed catalysts of this paper, which is nearest to the monolayer dispersion saturated state of V2O5/TiO2 catalyst. Moreover, it convincingly demonstrate the obvious threshold effect in V2O5 catalysts.

Experimental Study of High-Frequency Vibration Assisted Micro/Meso-Scale Forming of Metallic Materials

Micro/meso-scale forming is a promising technology for mass production of miniature metallic parts. However, fabrication of micro/meso-scale features leads to challenges due to the friction increase at the interface and tool wear from highly localized stress. In this study, the use of high-frequency vibration for potential application in the technology of micro/meso-scale forming has been investigated. A versatile experimental setup based on a magnetostrictive (Terfenol-D) actuator was built. Vibration assisted micro/meso-scale upsetting, pin extrusion and cup extrusion were conducted to understand the effects of workpiece size, excitation frequency and the contact condition. Results showed a change in load reduction behavior that was dependent on the excitation frequency and contact condition. The load reduction can be explained by a combination of stress superposition and friction reduction. It was found that a higher excitation frequency and a less complicated die-specimen interface were more likely to result in a friction reduction by high-frequency vibration

The commissioning of the CUORE experiment: the mini-tower run

CUORE is a ton-scale experiment approaching the data taking phase in Gran Sasso National Laboratory. Its primary goal is to search for the neutrinoless double-beta decay in 130Te using 988 crystals of tellurim dioxide. The crystals are operated as bolometers at about 10 mK taking advantage of one of the largest dilution cryostat ever built. Concluded in March 2016, the cryostat commissioning consisted in a sequence of cool down runs each one integrating new parts of the apparatus. The last run was performed with the fully configured cryostat and the thermal load at 4 K reached the impressive mass of about 14 tons. During that run the base temperature of 6.3 mK was reached and maintained for more than 70 days. An array of 8 crystals, called mini-tower, was used to check bolometers operation, readout electronics and DAQ. Results will be presented in terms of cooling power, electronic noise, energy resolution and preliminary background measurements

Results from the Cuore Experiment

The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for neutrinoless double beta decay that has been able to reach the 1-ton scale. The detector consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers, each of them made of 52 crystals. The construction of the experiment was completed in August 2016 and the data taking started in spring 2017 after a period of commissioning and tests. In this work we present the neutrinoless double beta decay results of CUORE from examining a total TeO2 exposure of 86.3kg yr, characterized by an effective energy resolution of 7.7 keV FWHM and a background in the region of interest of 0.014 counts/ (keV kg yr). In this physics run, CUORE placed a lower limit on the decay half- life of neutrinoless double beta decay of 130Te > 1.3.1025 yr (90% C. L.). Moreover, an analysis of the background of the experiment is presented as well as the measurement of the 130Te 2vo3p decay with a resulting half- life of T2 2. [7.9 :- 0.1 (stat.) :- 0.2 (syst.)] x 10(20) yr which is the most precise measurement of the half- life and compatible with previous results

Microscopic Phase Structure of Mo-based Catalyst and Its Catalytic Activity for Soot Oxidation

The MoO3 catalysts supported on nano-scale TiO2 with various loading rates (5%, 10%, 20%, and 40%) were prepared by an impregnation method. The phase structures of nano-scale MoO3/TiO2 catalysts were characterized by Brunner-Emmet-Teller, Fourier Transform Infrared Spectra, X-ray Diffraction, and Scanning Electron Microscope. The oxidation activities of catalysts over diesel soot were performed in a Thermogravimetric Analysis system. The kinetics of the catalytic oxidation process was analyzed based on Starink method. The characterization results showed that the phase structure of MoO3 supported on TiO2 depends heavily on the molybdenum contents, which put great effects on soot oxidation. The orthorhombic crystal system (α-MoO3) appeared on the surface of the catalysts when the MoO3 exceeds 10%. Due to the low melting point and good surface mobility of MoO3, the catalytic activity was increased and the characteristic temperatures were decreased with the increase in MoO3 contents. As a result, the activities of catalysts with different loading rates for soot oxidation can be ranked as: Mo

Flexible Tactile Sensor Array for Slippage and Grooved Surface Recognition in Sliding Movement

Flexible tactile sensor with contact force sensing and surface texture recognition abilities is crucial for robotic dexterous grasping and manipulation in daily usage. Different from force sensing, surface texture discrimination is more challenging in the development of tactile sensors because of limited discriminative information. This paper presents a novel method using the finite element modeling (FEM) and phase delay algorithm to investigate the flexible tactile sensor array for slippage and grooved surfaces discrimination when sliding over an object. For FEM modeling, a 3 &times; 3 tactile sensor array with a multi-layer structure is utilized. For sensor array sliding over a plate surface, the initial slippage occurrence can be identified by sudden changes in normal forces based on wavelet transform analysis. For the sensor array sliding over pre-defined grooved surfaces, an algorithm based on phase delay between different sensing units is established and then utilized to discriminate between periodic roughness and the inclined angle of the grooved surfaces. Results show that the proposed tactile sensor array and surface texture recognition method is anticipated to be useful in applications involving human-robotic interactions