scholarly journals Research of Single-Particle Compression Ratio and Prediction of Crushed Products and Wear on the 6-DOF Robotic Crusher

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Guochen Duan ◽  
Boqiang Shi ◽  
Jie Gu
Keyword(s):  
Granular Material ◽  
Compression Ratio ◽  
Single Particle ◽  
Functional Model ◽  
Wear Model ◽  
Traditional Structure ◽  
Cone Crusher ◽  
The Difference ◽  
Whole Life Cycle ◽  
Chamber Size

In order to reduce wear and increase crushing efficiency of the 6-DOF (degree of freedom) robotic crusher, the maximum single-particle compression ratio function of the granular material and the wear model of the mantle liner under eccentric compression are established. The function and model take into account the influence of crusher parameters and granular material parameters on maximum single-particle compression ratio, which is simulated by EDEM and obtained under different conditions. Combined with previous research, the theoretical distribution of crushed products and the crushing chamber size can be obtained at each time of the whole life cycle of the liner. Compared with the experimental data of Ansteel Group in previous research, the difference between the functional model and the actual results is small. This function is universal and can be used to provide reference for the 6-DOF robotic crusher’s crushing strategy and a theoretical basis and a design reference of the traditional structure cone crusher.

scholarly journals A new method for measuring optical scattering properties of atmospherically relevant dusts using the Cloud and Aerosol Spectrometer with Polarization (CASPOL)

2013 ◽  
Vol 13 (3) ◽  
pp. 1345-1356 ◽  
Author(s):  
A. Glen ◽  
S. D. Brooks
Keyword(s):  
Cross Sections ◽  
Atmospheric Aerosols ◽  
Single Particle ◽  
Global Climate ◽  
Optical Scattering ◽  
Measurement Tool ◽  
Optical Signature ◽  
New Instrument ◽  
The Difference ◽  
Atmospherically Relevant

Abstract. Atmospheric aerosols have major impacts on regional and global climate through scattering and absorption of solar radiation. A new instrument, the Cloud and Aerosol Spectrometer with Polarization (CASPOL) from Droplet Measurement Technologies measures light scattered by aerosols in the forward (4° to 12°) and backward (168° to 176°) directions, with an additional polarized detector in the backward direction. Scattering by a single particle can be measured by all three detectors for aerosols in a broad range of sizes, 0.6 μm < diameter < 50 μm. The CASPOL is a unique measurement tool, since unlike most in-situ probes, it can measure optical properties on a particle-by-particle basis. In this study, single particle CASPOL measurements for thirteen atmospherically relevant dusts were obtained and their optical scattering signatures were evaluated. In addition, Scanning Electron Microscopy (SEM) was used to characterize the shape and morphology of each type of dust. The total and polarized backscatter intensities varied with particle size for all dust types. Using a new optical signature technique all but one dust type could be categorized into one of three optical scattering groups. Additionally, a composite method was used to derive the optical signature of Arizona Test Dust (ATD) by combining the signatures of its major components. The derived signature was consistent with the measured signature of ATD. Finally, calculated backscattering cross sections for representative dust from each of the three main groups were found to vary by as much as a factor of 7, the difference between the backscattering cross sections of white quartz (5.3 × 10−10 cm−2) and hematite (4.1 × 10−9 cm−2).

Number of spikes in single particle ICP-MS time scans: from the very dilute to the highly concentrated range

2021 ◽  
Author(s):  
Pierre-Emmanuel Peyneau ◽  
Martin Guillon
Keyword(s):  
Single Particle ◽  
Inductively Coupled Plasma ◽  
Particle Number ◽  
Number Concentration ◽  
Particle Number Concentration ◽  
Inductively Coupled ◽  
Nanoparticle Dispersions ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
The Difference

The particle number concentration (PNC) of dilute nanoparticle dispersions can be determined by single particle inductively coupled plasma-mass spectrometry (sp-ICP-MS). Virtually equal to zero for very dilute dispersions, the difference...

scholarly journals Establishment of a Laminated Crushed Products Function and Numerical Analysis

Energies ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 819 ◽  
Author(s):  
Guochen Duan ◽  
Boqiang Shi ◽  
Yanhua Shen ◽  
Guoqing Yu
Keyword(s):  
Particle Size ◽  
Numerical Analysis ◽  
Compression Ratio ◽  
Single Particle ◽  
Functional Relationship ◽  
Distinct Element ◽  
Confining Pressure ◽  
Ratio Model ◽  
Relative Compression ◽  
Granular Particles

A model of the relative compression ratio for single-particle crushed products, based on the distinct element method (DEM) and numerical analysis, was established to describe precisely the crushed products of granular particles during laminated crushing. The relative compression ratio model was used to describe the functional relationship between the total compression ratio and the single-particle compression ratio, which can be described by lognormal distribution. The single-particle crushed products model was used to describe the functional relationship between the single-particle compression ratio and the distribution of single-particle crushed products. The distribution of single-particle crushed products was described by a three-parameter beta distribution. On the basis of the above model, the function of laminated crushed products of granular particles was established. According to the simulation results of EDEM under confining pressure, a functional relationship between total compression ratio, particle size, and height of the granular particles for laminated crushed products of granular particles was built. It was proved that the function of the theoretical particle size distribution coefficient of laminated crushed products of granular particles was not too different from the actual value determined by simulation. The function is universal and can be used to provide a theoretical basis and a design reference for the design of cone crushers, high-pressure roller mills, and other crushing equipment.

The Prediction of Wear in Fluidized Beds

1995 ◽  
Vol 117 (2) ◽  
pp. 142-149 ◽  
Author(s):  
W. A. Rogers
Keyword(s):  
Fluidized Bed ◽  
Single Particle ◽  
Fluidized Beds ◽  
Tube Bundle ◽  
Optimization Procedure ◽  
Quantitative Agreement ◽  
Particle Collisions ◽  
Wear Model ◽  
Wear Rates ◽  
Fluidized Particles

A procedure is formulated to model impact and abrasion wear of surfaces exposed to a fluidized bed. A methodology adapting a single-particle wear model and the kinetic theory of gases to granular flows is used to develop a model accounting for impact wear from all possible particle collisions. Abrasive wear is modeled using a single-particle abrasion model adapted to describe the effects of many abrading particles. Parameters describing granular flow are necessary for evaluation of the resulting wear expressions. They are determined by numerical solution of the conservation equations describing fluidized-bed hydrodynamics. Additional parameters appear in the wear expressions which describe the contact between individual fluidized particles and the wearing surface. These are determined by an optimization procedure which minimizes error between predicted and measured wear rates. The modeling procedure was used to analyze several bubbling and turbulent fluidized bed experiments with single-tube and tube bundle configurations. Quantitative agreement between the measured and predicted wear rates was found, with some exceptions for local wear predictions. This work demonstrates a methodology for wear predication in fluidized beds.

scholarly journals A new method for measuring optical scattering properties of atmospherically relevant dusts using the Cloud Aerosol Spectrometer Polarization (CASPOL) instrument

2012 ◽  
Vol 12 (8) ◽  
pp. 22415-22449 ◽  
Author(s):  
A. Glen ◽  
S. D. Brooks
Keyword(s):  
Cross Sections ◽  
Atmospheric Aerosols ◽  
Single Particle ◽  
Global Climate ◽  
Optical Scattering ◽  
Measurement Tool ◽  
Optical Signature ◽  
New Instrument ◽  
The Difference ◽  
Atmospherically Relevant

Abstract. Atmospheric aerosols have major impacts on regional and global climate through scattering and absorption of atmospheric radiation. A new instrument, the Droplet Measurement Technologies Cloud Aerosol Spectrometer Polarization Option (CASPOL) measures light scattered by aerosols in the forward (4° to 12°) and backward (168° to 176°) directions, with an additional polarized detector in the backward direction. Scattering by a single particle can be measured by all three detectors for aerosols in a broad range of sizes, 0.6 μm < diameter < 50 μm. The CASPOL is a unique measurement tool, since very few in situ probes can measure optical properties on a particle-by-particle basis. In this study, single particle CASPOL measurements for thirteen atmospherically relevant dusts were obtained and their optical scattering signatures were evaluated. In addition, Scanning Electron Microscopy (SEM) was used to characterize the shape and morphology of each type of dust. The total and polarized backscatter intensities varied with particle size for all dust types. Using a new optical signature technique all but one dust type could be categorized into one of three optical scattering groups. Additionally, a composite method was used to derive the optical signature of Arizona Test Dust (ATD) by combining the signatures of its major components. The derived signature was consistent with the measured signature of ATD. Finally, calculated backscattering cross sections for representative dust from each of the three main groups were found to vary by as much as a factor of 7, the difference between the backscattering cross sections of white quartz (5.3 × 10−10 cm−2) and hematite (4.1 × 10−9 cm−2).

scholarly journals Can a bog drained for forestry be a stronger carbon sink than a natural bog forest?

2014 ◽  
Vol 11 (2) ◽  
pp. 2189-2226 ◽  
Author(s):  
J. Hommeltenberg ◽  
H. P. Schmid ◽  
M. Droesler ◽  
P. Werle
Keyword(s):  
Carbon Fixation ◽  
Carbon Sink ◽  
Ecosystem Respiration ◽  
Net Ecosystem Exchange ◽  
Weather Conditions ◽  
Co2 Exchange ◽  
Co2 Uptake ◽  
Spruce Forest ◽  
The Difference ◽  
Whole Life Cycle

Abstract. This study compares the CO2 exchange of a natural bog forest, and of a bog drained for forestry in the pre-alpine region of southern Germany. The sites are separated by only ten kilometers, they share the same formation history and are exposed to the same climate and weather conditions. In contrast, they differ in land use history: at the Schechenfilz site a natural bog-pine forest (Pinus mugo rotundata) grows on an undisturbed, about 5 m thick peat layer; at Mooseurach a planted spruce forest (Picea abies) grows on drained and degraded peat (3.4 m). The net ecosystem exchange of CO2 (NEE) at both sites has been investigated for two years (July 2010 to June 2012), using the eddy covariance technique. Our results indicate that the drained, forested bog at Mooseurach is a much stronger carbon dioxide sink (−130 ± 31 and −300 ± 66 g C m−2 a−1 in the first and second year respectively) than the natural bog forest at Schechenfilz (−53 ± 28 and −73±38 g C m−2 a−1). The strong net CO2 uptake can be explained by the high gross primary productivity of the spruces that over-compensates the two times stronger ecosystem respiration at the drained site. The larger productivity of the spruces can be clearly attributed to the larger LAI of the spruce site. However, even though current flux measurements indicate strong CO2 uptake of the drained spruce forest, the site is a strong net CO2 source, if the whole life-cycle, since forest planting is considered. We determined the difference between carbon fixation by the spruces and the carbon loss from the peat due to drainage since forest planting. The estimate resulted in a strong carbon release of +156 t C ha−1 within the last 44 yr, means the spruces would need to grow for another 100 yr, at the current rate, to compensate the peat loss of the former years. In contrast, the natural bog-pine ecosystem has likely been a small but consistent carbon sink for decades, which our results suggest is very robust regarding short-term changes of environmental factors.

scholarly journals WHY HOLES ARE NOT LIKE ELECTRONS III: HOW HOLES IN THE NORMAL STATE TURN INTO ELECTRONS IN THE SUPERCONDUCTING STATE

2009 ◽  
Vol 23 (14) ◽  
pp. 3035-3057 ◽  
Author(s):  
J. E. HIRSCH
Keyword(s):  
Single Particle ◽  
Normal State ◽  
Superconducting State ◽  
Negative Charge ◽  
Energy Levels ◽  
Particle Energy ◽  
Point Of View ◽  
Electron Interaction ◽  
Single Particle Energy ◽  
The Difference

In recent work, we discussed the difference between electrons and holes in energy band in solids from a many-particle point of view, originating in the electron–electron interaction,1 and from a single particle point of view, originating in the electron–ion interaction.2 We proposed that superconductivity in solids only occurs when the Fermi level is close to the top of a band (hole carriers), that it originates in "undressing" of carriers from both the electron–electron and the electron–ion interaction, and that as a consequence holes in the normal state behave like electrons in the superconducting state.3 However, the connection between both undressing effects was left unclear, as was left unclear how the transformation from hole behavior to electron behavior occurs. Here, we clarify these questions by showing that the same electron–electron interaction physics that promotes pairing of hole carriers and undressing of carriers from the electron–electron interaction leads to undressing of carriers from the electron–ion interaction and transforms the behavior of carriers from hole-like to electron-like. A complete reorganization of the occupation of single-particle energy levels occurs. Furthermore this phenomenon is connected with the expulsion of negative charge that we predict to occur in superconductors. These unexpected connections support the validity of our theoretical framework, the theory of hole superconductivity, to explain superconductivity in solids.

scholarly journals Magnetic Quantum Otto Engine for the Single-Particle Landau Problem

2017 ◽  
Author(s):  
Francisco J. Peña ◽  
Alejandro González ◽  
A.S. Nunez ◽  
Pedro Orellana ◽  
René G. Rojas ◽  
...  
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Field Intensity ◽  
Compression Ratio ◽  
Single Particle ◽  
Magnetic Field Intensity ◽  
Energy Levels ◽  
Adiabatic Process ◽  
Adiabatic Processes ◽  
The Magnetic Field

We study the effect of the degeneracy factor in the energy levels of the well-known Landau problem for a magnetic quantum Otto engine. The scheme of the cycle is composed of two quantum adiabatic processes and two quantum isomagnetic processes driven by a quasi-static modulation of external magnetic field intensity. We derive the analytical expression of the relation between the magnetic field and temperature along the adiabatic process and, in particular, reproduce the expression for the efficiency as a function of the compression ratio.

scholarly journals Molecular dynamics study on single particle displacement damage of ZB InN

2021 ◽  
Vol 2133 (1) ◽  
pp. 012042
Author(s):  
Tongxuan Jia ◽  
Xie Yang ◽  
Zujun Wang ◽  
Yonggang Huo ◽  
Aiguo Shang ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Single Particle ◽  
Particle Displacement ◽  
Initial Displacement ◽  
Displacement Damage ◽  
Vacancy Defects ◽  
Antisite Defects ◽  
The Difference ◽  
Formation Efficiency ◽  
Atomic Type

Abstract To evaluate single-particle initial displacement damage of InN, the MD method is used to simulate the cascades, where the energy of PKA (E PKA) ranges from 1 to 5 keV. From these results, we can find that high EPKA will increase Np and Ns of defects, and aggravate the damage of InN, which is more obvious in Frenkel pairs. The formation efficiency of vacancy and interstitial is influenced by antisite defects, thereby causing the difference between vacancies and interstitials for the same atomic type. About the distribution of InN defects, it is mainly caused by vacancy defects, indicating that vacancy damage occupies the main position in displacement damage.

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