Tire Treadwear — A Comprehensive Evaluation of the Factors: Generic Type, Aspect Ratio, Tread Pattern, and Tread Composition Part III: Results of Supplementary and UTQG Treadwear Test Series

1986 ◽  
Vol 14 (4) ◽  
pp. 235-263
Author(s):  
A. G. Veith
Keyword(s):  
Carbon Black ◽  
Comprehensive Evaluation ◽  
Work Intensity ◽  
Generic Type ◽  
Aspect Ratios ◽  
Index Variation ◽  
Primary Determinant ◽  
Severity Levels ◽  
High Test ◽  
Better Than

Abstract The effect of tread compound variation on tire treadwear was studied using bias and radial tires of two aspect ratios. Compound variations included types of rubber and carbon black as well as the levels of carbon black, process oil, and curatives. At low to moderate test severity, SBR and an SBR/BR blend performed better than NR while at high test severity NR and SBR were better than the SBR/BR blend. The SBR/BR blend was the best at low severity testing. Higher structure and higher surface area carbon black gave improved treadwear at all severity levels. The concept of a “frictional work intensity” as the primary determinant of treadwear index variation with test severity is proposed. Some factors which influence frictional work intensity are discussed.

Dispersion of Layered Organosilicates in Isobutylene-Based Elastomers

2006 ◽  
Vol 79 (2) ◽  
pp. 281-306 ◽  
Author(s):  
Andy H. Tsou ◽  
Matthew B. Measmer
Keyword(s):  
Aspect Ratio ◽  
Carbon Black ◽  
Layered Silicate ◽  
Tertiary Amines ◽  
Aspect Ratios ◽  
Silicate Nanocomposites ◽  
Dispersion State ◽  
Planar Orientation ◽  
Internal Mixer ◽  
Better Than

Abstract Dispersion morphologies of polymer-layered silicate nanocomposites based on either brominated poly(isobutylene-co-para-methylstyrene), BIMSM, or brominated poly(isobutylene-co-isoprene), BIIR, and an organosilicate, dimethylditallow ammonium-exchanged montmorillonite, Cloisite™ 6A, with and without N660 carbon black fillers were examined using SAXS, WAXS, AFM, and TEM. These compounds were prepared using an internal mixer and cured for property measurements. Due to the observed partial orientation of organosilicates and their possible heterogeneous intercalation, degrees of exfoliation and dispersion of organosilicates in BIMSM and BIIR were unable to be characterized and quantified simply by TEM, AFM, or SAXS alone. Instead, using the projected aspect ratio of organosilicates in BIMSM or BIIR, extracted from Gusev-Lusti equation based on measured permeability ratios, was found to provide a relative measure of their dispersion state. Since better dispersion, higher planar orientation, and/or increasing extent of exfoliation lead to higher aspect ratio, this calculated aspect ratio was used as a measure of organosilicate dispersion in BIMSM and BIIR compounds. According to experimentally extracted projected aspect ratios, it was found that BIMSM disperses organosilicates better than BIIR and that carbon black filler does not affect the organosilicate dispersion in BIMSM. Addition of tertiary amines in BIMSM enhances the dispersion of organosilicates, possibly through favorable interactions between organosilicates and quaternary ammonium functionalized BIMSM, resulting in further reduction in permeability.

Study on Thermal Conductivity of Composites of Rubber/CB with Good Electrical Properties

2011 ◽  
Vol 221 ◽  
pp. 466-471 ◽  
Author(s):  
Jun Ping Song ◽  
Yan He ◽  
Lian Xiang Ma
Keyword(s):  
Thermal Conductivity ◽  
Carbon Black ◽  
Filler Loading ◽  
Graphitized Carbon Black ◽  
Acetylene Black ◽  
Rubber Matrix ◽  
Rubber Composites ◽  
Graphitized Carbon ◽  
The Difference ◽  
Better Than

Graphitized carbon black 40b2 and acetylene black were filled separately in natural rubber matrix for preparing vulcanized rubber. The thermal conductivity of both kinds of composites was studied considering filler loading and temperature. SEM and TEM were applied to observe morphology of the filler and composites. The experimental results show that thermal conductivity of acetylene black/rubber composites is much better than that of graphitized carbon black 40b2/rubber composites, which is opposite to the electric conduction properties. As filler loading increased, the difference increased, and when the filler loading is up to 40phr, the thermal conductivity value of acetylene black/rubber composite is 53% larger than the other one. TEM shows that acetylene black has more botryoidal structure, larger carbon black aggregates in size, and much looser surface than 40b2.Moreover, for acetylene black, particles contact by surface mainly, and for 40b2, particles contact by point mainly. SEM shows that the distribution of carbon black 40b2 in rubber matrix is much better than acetylene black. The better thermal conductivity for acetylene black is attributed to the higher structure, nonuniform distribution in rubber matrix and surface contact between particles.

Influence of Distal Resistance and Proximal Vascular Stiffness on Vascular Impedance and Hemodynamics in Pulmonary Hypertension: A Computational Study With Validation Using an Animal Model

2009 ◽  
Author(s):  
Zhenbi Su ◽  
Kendall Hunter ◽  
Wei Tan ◽  
Robin Shandas
Keyword(s):  
Pulmonary Hypertension ◽  
Computational Study ◽  
Mean Flow ◽  
Vascular Impedance ◽  
Vascular Flow ◽  
Primary Determinant ◽  
Mean Pressure ◽  
Pulmonary Arterial ◽  
The Relationship ◽  
Better Than

Clinically, invasive measurement of pulmonary vascular flow and pressure provides the hemodynamic status of the pulmonary circulation with pulmonary arterial hypertension (PAH). Current diagnostics and therapeutics for PAH revolve around pulmonary vascular resistance (PVR), which is determined by the mean pressure divided by mean flow [1]. Though PVR correlates well with right ventricular (RV) afterload, failure of which is the primary determinant of mortality [2–4], PVR does not provide the complete measure of RV afterload since it neglects dynamic impedance effects [4, 5]. Although we have shown that impedance predicts clinical outcomes better than PVR alone, several key questions remain about the relationship between hemodynamics and impedance changes in pulmonary hypertension.

Research and Evaluation on the Machining Properties of Picea spp.

2012 ◽  
Vol 538-541 ◽  
pp. 1403-1407 ◽  
Author(s):  
Chu Wang Su ◽  
Ze Kun Wang ◽  
Li Wei Hu ◽  
Jing Da Huang ◽  
Qi Jian Li
Keyword(s):  
New Zealand ◽  
Evaluation System ◽  
Comprehensive Evaluation ◽  
Forest Research Institute ◽  
Forest Research ◽  
Machining Performance ◽  
Comprehensive Evaluation System ◽  
Machining Properties ◽  
Better Than ◽  
Research Institute

In this paper, the machining properties of Picea spp., compared with Castanopsis hystrix, were tested. Their properties were conducted according to the criteria ASTM D1666-87 and the test on crosscutting is referred to the method established by New Zealand Forest Research Institute. The results show as follow: The machining properties of Picea spp. and Castanopsis hystrix show excellent in the planning, sanding, boring, shaping and crosscutting, but in the mortising properties, Picea spp. which was a bit poor shows fair and Castanopsis hystrix shows good. The properties of Picea spp. were in an all-round way better than Castanopsis hystrix. In the machining performance comprehensive evaluation system for full marks 50 points, their comprehensive marks were separately 45.5 points and 44.4 points.

Grindability Evaluation of Advanced Ceramics

2004 ◽  
Vol 471-472 ◽  
pp. 132-135 ◽  
Author(s):  
Ai Bing Yu ◽  
L.J. Zhong ◽  
Xin Li Tian
Keyword(s):  
Evaluation System ◽  
Comprehensive Evaluation ◽  
Fuzzy Comprehensive Evaluation ◽  
Experimental Results ◽  
Fuzzy Evaluation ◽  
Grinding Forces ◽  
Principal Stresses ◽  
Advanced Ceramics ◽  
Evaluation Theory ◽  
Better Than

Evaluation system of grindability was proposed for advanced ceramics. Grinding forces and material removals of SiC, Al2O3, Si3N4 and ZrO2 were measured. Grindabilities of ceramics were evaluated with property parameters based on fuzzy comprehensive evaluation theory. The experimental results suggest that grindabilities of SiC and Al2O3 are better than those of Si3N4 and ZrO2. The fuzzy evaluation results show grindabilities of SiC and Al2O3 ceramics are classified as grade of very easy to grind, and Si3N4 and ZrO2 are classified as grade of difficult to grind. The ranking of maximum grinding principal stresses of ceramics considering Poisson’s ratio is SiC, Al2O3, ZrO2 and Si3N4. Theoretical analysis calculated with property parameters is consistent with experimental results in comparison of grinding output parameters. The proposed evaluation system for ceramic grindability is feasible, and the evaluated results are comprehensive and reasonable.

scholarly journals An Evaluation and Dissemination Model for the Machine Learning Embedded System Lifecycle in Clinical Practice Settings

2021 ◽  
Author(s):  
melanie besculides ◽  
Ksenia Gorbenko ◽  
Cardinale Smith ◽  
Robert Freeman ◽  
David Reich ◽  
...  
Keyword(s):  
Machine Learning ◽  
Clinical Practice ◽  
Embedded System ◽  
Quantitative Methods ◽  
Clinical Decision Making ◽  
Comprehensive Evaluation ◽  
Healthcare Setting ◽  
Clinical Decision ◽  
Qualitative And Quantitative Methods ◽  
Better Than

Machine learning (ML) algorithms are gaining popularity in clinical practice settings due to their ability to process information in ways that augment human reasoning. While tools that rely on output from ML algorithms in the healthcare setting are appealing for their ability to aid in clinical decision making and streamline workflows, their implementation and effectiveness are not well documented. There is an abundance of published ML literature that focuses on whether algorithms can predict an outcome or predict it better than previous algorithms, but a dearth of effort evaluating their implementation or impact on patient outcomes. While developing and validating algorithms is an important first step in research, comprehensive evaluation is needed before application of ML algorithms in new settings is considered. Evaluation should examine both the process of implementation and the outcomes using a mix of qualitative and quantitative methods. This commentary describes a model we developed to guide our institutional ML evaluation efforts.

scholarly journals Comparison of Ultrasound Type and Working Parameters on the Reduction of Four Higher Alcohols and the Main Phenolic Compounds

2021 ◽  
Vol 14 (1) ◽  
pp. 417
Author(s):  
Qingan Zhang ◽  
Hongrong Zheng ◽  
Shuang Cheng ◽  
Bowen Xu ◽  
Penghui Guo
Keyword(s):  
Phenolic Compounds ◽  
Red Wine ◽  
Comprehensive Evaluation ◽  
Higher Alcohols ◽  
Single Factor ◽  
Color Properties ◽  
Color Parameters ◽  
Ultrasound Bath ◽  
Working Parameters ◽  
Better Than

In this paper, studies were conducted by a series of single-factor experiments to investigate the effects of ultrasound types and working parameters on the higher alcohols (HA), phenolic compounds, and color properties of red wine, so as to highlight the importance of the comprehensive consideration on its application. The results indicate that ultrasound devices and working parameters do have some definite influences on the HA of wine; moreover, the ultrasound bath (SB-500DTY) is better than the SCIENTZ-950E and the KQ-300VDE. With the SB-500DTY employed to further investigate its effects on phenols and color properties other than on HA, unexpectedly, some variations of color parameters are opposite to the results ever obtained from other ultrasound conditions. In summary, all these results suggest that both the ultrasound type and parameters should be fully considered or neutralized so as to have a comprehensive evaluation about its application, instead of some contradictory results.

STUDIES OF CARBON BLACK: III. THE CHANNEL PROCESS—PRODUCTION FROM PYROLYSIS WASTE GASES

1937 ◽  
Vol 15b (4) ◽  
pp. 139-155 ◽  
Author(s):  
L. M. Pidgeon
Keyword(s):  
Carbon Black ◽  
Gas Mixtures ◽  
Hydrocarbon Mixture ◽  
Rubber Industry ◽  
Channel Process ◽  
Experimental Channel ◽  
Synthetic Gas ◽  
Better Than ◽  
Propane Butane

The waste gases obtained during the pyrolysis, in baffled metal tubes, of 70:30 propane-butane mixtures at temperatures between 800° and 850 °C., with the object of producing liquid aromatics, have been used to produce carbon black in an experimental channel plant. The hydrocarbon mixture if utilized directly to produce carbon black yielded up to 4.9 lb. per 1,000 cu. ft. When the mixture was subjected to pyrolysis about 33 lb. of liquids (23 lb. in the gasoline range) was produced, while the off-gas yielded 5.4 lb. of carbon black. Yields of carbon black up to 10 lb. per 1000 cu. ft. were obtained with lower yields of liquid. Experiments on synthetic gas mixtures showed that the olefines were largely responsible for the production of carbon black from the pyrolysis off-gas. A large number of tests on rubber indicated that the carbon reinforces rubber in a manner as good as or better than that of the commercial gas blacks at present used in the rubber industry.

Carbon gas diffusion electrodes promoted with silver and operating on air or oxygen in alkaline medium. Physical parameters of electrodes and their components

1983 ◽  
Vol 48 (8) ◽  
pp. 2165-2174
Author(s):  
Karel Smrček ◽  
Martin Wedell ◽  
Jiří Mrha ◽  
Miroslava Musilová
Keyword(s):  
Carbon Black ◽  
Active Layer ◽  
Active Carbon ◽  
Gas Diffusion ◽  
Carbon Electrodes ◽  
Physical Parameters ◽  
Gas Diffusion Electrodes ◽  
Hydrophobic Nature ◽  
Better Than

From the ratio of hydrophobic to hydrophilic pore volumes determined after a long-term exposure of the gas or active layer to water, the strong hydrophobic nature of the teflonized carbon black contained in carbon-based gas diffusion electrodes was confirmed. This material proves better than Teflon in Teflon-bonded active carbon electrodes, whose hydrophobicity is adversely affected on heating and the mechanical strength of the layer decreases. Measurement of the penetration of water and rate of flow of oxygen revealed that the teflonized carbon black ensures two essential functions of the gas diffusion electrode: feeding the active layer with oxygen and prevention of flooding of the gas pores.

Viability of joined flight for small unmanned aerial vehicles

2019 ◽  
Vol 124 (1273) ◽  
pp. 297-322
Author(s):  
E. Levis ◽  
F. Pleho ◽  
J. Hedges
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Parametric Analysis ◽  
Aircraft Design ◽  
Relative Magnitude ◽  
Design Parameters ◽  
Wing Loading ◽  
Aerodynamic Efficiency ◽  
Aspect Ratios ◽  
Aerial Vehicles ◽  
Better Than

ABSTRACTThe range of small, electrically powered UAVs is still limited by the mass specific energy of batteries. This paper investigates the idea that, in cases where multiple aircraft must transit to the same location, savings in mass or an extension of achievable range are possible when they join wingtip-to-wingtip. The viability of joined flight is investigated by quantifying the relative magnitude of savings resulting from increased aerodynamic efficiency and that of penalties due to the increased structural and component weights. Through a parametric analysis the level of savings achievable is found to be greatly dependent on the proportion of the flight spent in a joined configuration and aircraft design parameters such as wing loading, aspect ratio and the added weight of the joining mechanism. A custom, multidisciplinary UAV sizing algorithm is presented and utilised to design several sample aircraft, featuring two different joining mechanism architectures. The results verify the findings of the parametric study and indicate that mass savings are possible only for moderate to low aspect ratios, with semi-permanent magnetic joining mechanism performing better than rigid structural ones, even when the joined fight segment accounts for only 30% of the total airborne time.

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