Random loose packing of cylindrical particles considering filling rate

2021 ◽  
Vol 386 ◽  
pp. 98-107
Author(s):  
Chengquan Zhang ◽  
Jun Gao ◽  
Yukun Xu ◽  
Yunfei Xia ◽  
Xiaobin Wei ◽  
...  
Keyword(s):  
Filling Rate ◽  
Loose Packing ◽  
Cylindrical Particles

Void fraction for random loose packing of the cylindrical particles considering filling rate, material and shape

Particuology ◽  
2021 ◽  
Author(s):  
Chengquan Zhang ◽  
Jun Gao ◽  
Yukun Xu ◽  
Yunfei Xia ◽  
Xiaobin Wei ◽  
...  
Keyword(s):  
Void Fraction ◽  
Filling Rate ◽  
Loose Packing ◽  
Cylindrical Particles

scholarly journals Porous Structure of Cylindrical Particle Compacts

Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1498
Author(s):  
Aidana Boribayeva ◽  
Gulfairuz Iniyatova ◽  
Aruzhan Uringaliyeva ◽  
Boris Golman
Keyword(s):  
Voronoi Tessellation ◽  
Spherical Particles ◽  
Energy Storage Devices ◽  
Voronoi Cells ◽  
Storage Devices ◽  
Aspect Ratios ◽  
Loose Packing ◽  
Porous Microstructure ◽  
Porous Compacts ◽  
Cylindrical Particles

The porous compacts of non-spherical particles are frequently used in energy storage devices and other advanced applications. In the present work, the microstructures of compacts of monodisperse cylindrical particles are investigated. The cylindrical particles with various aspect ratios are generated using superquadrics, and the discrete element method was adopted to simulate the compacts formed under gravity deposition of randomly oriented particles. The Voronoi tessellation is then used to quantify the porous microstructure of compacts. With one exception, the median reduced free volume of Voronoi cells increases, and the median local packing density decreases for compacts composed of cylinders with a high aspect ratio, indicating a loose packing of long cylinders due to their mechanical interlocking during compaction. The obtained data are needed for further optimization of compact porous microstructure to improve the transport properties of compacts of non-spherical particles.

Beurteilung der Adriamycin-Kardiotoxizität mittels der Äquilibrium-Radionuklid-Ventrikulographie

1987 ◽  
Vol 26 (05) ◽  
pp. 206-211 ◽  
Author(s):  
P. Knesewitsch ◽  
N. H. Göldel ◽  
S. Fritsch ◽  
E. Moser
Keyword(s):  
Left Ventricular ◽  
Peak Filling Rate ◽  
Base System ◽  
Filling Rate ◽  
Time To Peak ◽  
Ejection Rate ◽  
Follow Up Studies ◽  
Pathologic Findings ◽  
Peak Ejection Rate

Results of 606 equilibrium radionuclide ventriculographies (ERNV) performed in 348 non-selected patients receiving Adriamycin (ADM) therapy were stored in a data base system. The aim of the study was to assess the influence of a potential cardiotoxic therapy on left ventricular pump function. Increasing ADM doses yielded a significant (p <0.05) decrease of the resting ejection fraction (R-gEF), the peak ejection rate and the peak filling rate. Enddiastolic and endsystolic volumes increased significantly. Stroke volume, heart rate and time to peak filling rate did not change significantly. 368 follow-up studies were performed in 128 patients: 65/128 patients presented a decrease of R-gEF, but only in 45 of these patients R-gEF values fell into the pathologic range. In 44 of these follow-ups, R-gEF remained unchanged. In 19 patients, a R-gEF increase was observed. At the beginning of ADM therapy 14% of the patients had subnormal R-gEF values. With increasing ADM doses pathologic findings increased to 86% in patients with ADM doses higher than 500 mg/m2.

Effect of Polymer, Road Surface, and Driving Conditions on Wear Surface Characteristics of Tire Treads

1973 ◽  
Vol 1 (4) ◽  
pp. 354-362 ◽  
Author(s):  
F. R. Martin ◽  
P. H. Biddison
Keyword(s):  
Wear Surface ◽  
Surface Characteristics ◽  
Road Surface ◽  
The Other ◽  
Mechanical Degradation ◽  
Textured Surface ◽  
Test Track ◽  
Driving Conditions ◽  
Styrene Butadiene ◽  
Cylindrical Particles

Abstract Treads made with emulsion styrene-butadiene copolymer (SBR), solution SBR, polybutadiene (BR), and a 60/40 emulsion SBR/BR mixture were built as four-way tread sections on G78-15 belted bias tires, which were driven over both concrete and gravel-textured highways and on a small, circular, concrete test track. The tires were front mounted. When driven on concrete highway, all except the BR tread had either crumbled- or liquid-appearing surfaces, thought to have been formed by mechanical degradation or fatigue. When cornered on concrete, these materials formed small cylindrical particles or rolls. The BR tread had a smooth, granular-textured surface when driven on concrete highway and a ridge or sawtooth abrasion pattern when cornered on concrete. All the materials appeared rough and torn when run on gravel-textured highway. The differences in wear surface formed on BR tread and the other three are thought to be due primarily to the relatively high resilience of BR.

Effect of PASP-KT-NAA on Leaf Senescence and Grain Filling Rate during the Grain-Filling Period in Different Temperature Zones

2013 ◽  
Vol 38 (9) ◽  
pp. 1698-1709
Author(s):  
Tian-Jun XU ◽  
Zhi-Qiang DONG ◽  
Jiao GAO ◽  
Chuan-Xiao CHEN ◽  
Liu JIAO ◽  
...  
Keyword(s):  
Leaf Senescence ◽  
Grain Filling ◽  
Filling Rate ◽  
Grain Filling Rate ◽  
Grain Filling Period

Object Recognition Using the Shape Filling Rate

2010 ◽  
Vol 22 (6) ◽  
pp. 1016-1022
Author(s):  
Guocheng An ◽  
Fengjun Zhang ◽  
Guozhong Dai
Keyword(s):  
Object Recognition ◽  
Filling Rate

scholarly journals Blade Segment with a 3D Lattice of Diamond Grits Fabricated via an Additive Manufacturing Process

2020 ◽  
Vol 33 (1) ◽  
Author(s):  
Bin Chen ◽  
Peng Chen ◽  
Yongjun Huang ◽  
Xiangxi Xu ◽  
Yibo Liu ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Service Life ◽  
Manufacturing Process ◽  
Cutting Speed ◽  
Inspection System ◽  
Layer By Layer ◽  
Filling Rate ◽  
Pressure System ◽  
Manufacturing Equipment ◽  
Diamond Blade

Abstract Diamond tools with orderly arrangements of diamond grits have drawn considerable attention in the machining field owing to their outstanding advantages of high sharpness and long service life. This diamond super tool, as well as the manufacturing equipment, has been unavailable to Chinese enterprises for a long time due to patents. In this paper, a diamond blade segment with a 3D lattice of diamond grits was additively manufactured using a new type of cold pressing equipment (AME100). The equipment, designed with a rotary working platform and 16 molding stations, can be used to additively manufacture segments with diamond grits arranged in an orderly fashion, layer by layer; under this additive manufacturing process, at least 216000 pcs of diamond green segments with five orderly arranged grit layers can be produced per month. The microstructure of the segment was observed via SEM and the diamond blade fabricated using these segments was compared to other commercial cutting tools. The experimental results showed that the 3D lattice of diamond grits was formed in the green segment. The filling rate of diamond grits in the lattice could be guaranteed to be above 95%; this is much higher than the 90% filling rate of the automatic array system (ARIX). When used to cut stone, the cutting amount of the blade with segments made by AME100 is two times that of ordinary tools, with the same diamond concentration. When used to dry cut reinforced concrete, its cutting speed is 10% faster than that of ARIX. Under wet cutting conditions, its service life is twice that of ARIX. By applying the machine vision online inspection system and a special needle jig with a negative pressure system, this study developed a piece of additive manufacturing equipment for efficiently fabricating blade segments with a 3D lattice of diamond grits.

scholarly journals Impact of type 2 diabetes mellitus on left ventricular diastolic function in patients with essential hypertension: evaluation by volume-time curve of cardiac magnetic resonance

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Wei-feng Yan ◽  
Yue Gao ◽  
Yi Zhang ◽  
Ying-kun Guo ◽  
Jin Wang ◽  
...  
Keyword(s):  
Essential Hypertension ◽  
Diastolic Function ◽  
Control Group ◽  
Peak Strain ◽  
Filling Rate ◽  
Time Curve ◽  
Time To Peak ◽  
Peak Ejection Rate ◽  
Lv Diastolic Dysfunction

Abstract Background Essential hypertension and type 2 diabetes mellitus (T2DM) are two common chronic diseases that often coexist, and both of these diseases can cause heart damage. However, the additive effects of essential hypertension complicated with T2DM on left ventricle (LV) diastolic function have not been fully illustrated. This study aims to investigate whether T2DM affects the diastolic function of the LV in patients with essential hypertension using the volume-time curve from cardiac magnetic resonance (CMR). Methods A total of 124 essential hypertension patients, including 48 with T2DM [HTN(T2DM +) group] and 76 without T2DM [HTN(T2DM-) group], and 52 normal controls who underwent CMR scans were included in this study. LV volume-time curve parameters, including the peak ejection rate (PER), time to peak ejection rate (PET), peak filling rate (PFR), time to peak filling rate from end-systole (PFT), PER normalized to end-diastolic volume (PER/EDV), and PFR normalized to EDV (PFR/EDV), were measured and compared among the three groups. Multivariate linear regression analyses were performed to determine the effects of T2DM on LV diastolic dysfunction in patients with hypertension. Pearson correlation was used to analyse the correlation between the volume-time curve and myocardial strain parameters. Results PFR and PFR/EDV decreased from the control group, through HTN(T2DM −), to HTN(T2DM +) group. PFT in the HTN(T2DM-) group and HTN(T2DM +) group was significantly longer than that in the control group. The LV remodelling index in the HTN(T2DM −) and HTN(T2DM +) groups was higher than that in the normal control group, but there was no significant difference between the HTN(T2DM −) and HTN(T2DM +) groups. Multiple regression analyses controlling for covariates of systolic blood pressure, age, sex, and heart rate demonstrated that T2DM was independently associated with PFR/EDV (β = 0.252, p < 0.05). The volume-time curve method has good repeatability, and there is a significant correlation between volume-time curve parameters (PER/EDV and PFR/EDV) and myocardial peak strain rate, especially circumferential peak strain rate, which exhibited the highest correlation (r = − 0.756 ~ 0.795). Conclusions T2DM exacerbates LV diastolic dysfunction in patients with essential hypertension. The LV filling model changes reflected by the CMR volume-time curve could provide more information for early clinical intervention.

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