Occurrence and Prevention of Changes in the Chemical Structure of Natural Rubber Tire Tread Vulcanizates during Service

1970 ◽  
Vol 43 (5) ◽  
pp. 1215-1224 ◽  
Author(s):  
J. I. Cunneen ◽  
R. M. Russell
Keyword(s):  
Chemical Structure ◽  
Main Chain ◽  
Heavy Duty ◽  
Structural Alterations ◽  
The Road ◽  
Rubber Tire ◽  
Before And After ◽  
On The Road ◽  
The Stability ◽  
Made In

Abstract The chemical structure of the tread vulcanizate of heavy-duty tires has been investigated before and after service on the road, and after testing under conditions designed to induce tread-lift. Significant changes occurred. These included a marked reduction in the concentration of polysulfide crosslinks, and an increase in the amount of monosulfide crosslinks and main chain modification. Experiments with vulcanizates made in the laboratory indicated that the structural alterations in the tires were due to thermal anaerobic reactions caused by heat build-up, and that they resulted in a deterioration in some of the physical properties of the tread vulcanizate. The rate of desulfuration of ‘model’ polysulfides has been found to depend critically upon the nature of the vulcanization recipe. These novel findings point the way to improving the stability of vulcanizates used in the treads of tires and, consequently, tire performance.

Social Progress in Britain

2018 ◽  
Author(s):  
Anthony F. Heath ◽  
Elizabeth Garratt ◽  
Ridhi Kashyap ◽  
Yaojun Li ◽  
Lindsay Richards
Keyword(s):  
Free Market ◽  
Youth Unemployment ◽  
Social Progress ◽  
The Road ◽  
Social Divisions ◽  
Policy Interventions ◽  
The Usa ◽  
On The Road ◽  
Free Market Reforms ◽  
Made In

Social Progress in Britain examines how much progress has made in the years since Sir William Beveridge described the ‘five giants on the road to reconstruction’—the giants of Want, Disease, Ignorance, Squalor, and Idleness. The book has chapters examining the progress which Britain has made in improving material prosperity and tackling poverty; in extending length of life and tackling disease; in raising participation in education and improving educational standards; in tackling the scourge of unemployment, especially youth unemployment; and in providing better-quality housing and tackling overcrowding. In addition to Beveridge’s five giants, the book also explores inequalities of opportunity (focussing on inequalities between social classes, men and women, and ethnic groups), and the changing nature of social divisions and social cohesion in Britain. Throughout, the chapters put British progress into perspective by drawing comparisons with progress made in other large developed democracies such as Canada, France, Germany, Italy, Japan, Sweden, and the USA. As well as looking at the average level of prosperity, life expectancy, education, and housing, the book examines the extent of inequality around the average and pays particular attention to whether the most disadvantaged sections of society have shared in progress or have fallen behind. It concludes with an assessment of the effect of policy interventions such as Margaret Thatcher’s free market reforms of the 1980s on different aspects of social progress.

scholarly journals Measures to optimize traffic and the environment. Calculations of environmental safety on a given section of the Rostov-on-Don road network

2020 ◽  
pp. 68-77
Author(s):  
R. S. Durov ◽  
◽  
E. V. Varnakova ◽  
K. O. Kobzev ◽  
◽  
...  
Keyword(s):  
Road Network ◽  
Road Transport ◽  
Environmental Safety ◽  
Environmental Indicators ◽  
Nox Emissions ◽  
The Road ◽  
Before And After ◽  
Reduce Emissions ◽  
On The Road ◽  
State Of The Environment

Introduction. One of the most pressing socio-economic problems is the state of the environment, which affects the living conditions of many people. The article deals with the problem areas of the intersection of 20-ya Liniya street – Sholokhov Avenue in Rostov-on-Don. Problem Statement. The purpose of this paper is to improve environmental safety at the intersection of 20-ya Liniya street – Sholokhov Avenue in Rostov-on-Don by reducing emissions from road transport through the proposed measures to reorganize traffic on this section of the road network. Theoretical Part. The article provides an assessment of environmental and road safety on the road network section before applying the proposed measures. The measures are listed and justified that would help improve the conditions for road transport at the selected intersection and reduce emissions from road transport, which would improve environmental safety. The calculation of environmental indicators was made after the proposed measures to reduce NOx emissions by cars. Conclusion. The article analyzes the environmental indicators before and after the events, and then compares them. Based on the analysis and calculations, it is determined how much the proposed measures to optimize traffic will help reduce NOx emissions by cars.

scholarly journals Effect of Road Profile on Suspension System of Heavy Truck

2019 ◽  
Vol 12 (2) ◽  
pp. 71-75
Author(s):  
Salem F. Salman
Keyword(s):  
Steering System ◽  
Suspension System ◽  
The Road ◽  
Road Profile ◽  
Road Roughness ◽  
Road Type ◽  
Heavy Truck ◽  
Main Factors ◽  
On The Road ◽  
The Stability

All vehicles are affected by the type of the road they are moving on it.  Therefore the stability depends mainly on the amount of vibrations and steering system, which in turn depend on two main factors: the first is on the road type, which specifies the amount of vibrations arising from the movement of the wheels above it, and the second on is the type of the used suspension system, and how the parts connect with each other. As well as the damping factors, the tires type, and the used sprungs. In the current study, we will examine the effect of the road roughness on the performance coefficients (speed, displacement, and acceleration) of the joint points by using a BOGE device.

Recent Advances in Ordinal Analysis: Π12 — CA and Related Systems

1995 ◽  
Vol 1 (4) ◽  
pp. 468-485 ◽  
Author(s):  
Michael Rathjen
Keyword(s):  
Proof Theory ◽  
Formal System ◽  
Ordinal Analysis ◽  
The Road ◽  
Recent Success ◽  
Theoretic Proof ◽  
Independence Results ◽  
On The Road ◽  
Order Arithmetic ◽  
Made In

§1. Introduction. The purpose of this paper is, in general, to report the state of the art of ordinal analysis and, in particular, the recent success in obtaining an ordinal analysis for the system of -analysis, which is the subsystem of formal second order arithmetic, Z2, with comprehension confined to -formulae. The same techniques can be used to provide ordinal analyses for theories that are reducible to iterated -comprehension, e.g., -comprehension. The details will be laid out in [28]. Ordinal-theoretic proof theory came into existence in 1936, springing forth from Gentzen's head in the course of his consistency proof of arithmetic. Gentzen fostered hopes that with sufficiently large constructive ordinals one could establish the consistency of analysis, i.e., Z2. Considerable progress has been made in proof theory since Gentzen's tragic death on August 4th, 1945, but an ordinal analysis of Z2 is still something to be sought. However, for reasons that cannot be explained here, -comprehension appears to be the main stumbling block on the road to understanding full comprehension, giving hope for an ordinal analysis of Z2 in the foreseeable future. Roughly speaking, ordinally informative proof theory attaches ordinals in a recursive representation system to proofs in a given formal system; transformations on proofs to certain canonical forms are then partially mirrored by operations on the associated ordinals. Among other things, ordinal analysis of a formal system serves to characterize its provably recursive ordinals, functions and functionals and can yield both conservation and combinatorial independence results.

Influence of Silica Sand Particles on Disc Brake Squeal Noise

2013 ◽  
Vol 471 ◽  
pp. 81-85 ◽  
Author(s):  
Ahmad Razimi Mat Lazim ◽  
Abd Rahim Abu Bakar ◽  
Mohd Kameil Abdul Hamid ◽  
Izzat Mohd Asri
Keyword(s):  
Surface Condition ◽  
Surface Characteristics ◽  
Silica Sand ◽  
Brake Pad ◽  
Brake Squeal ◽  
The Road ◽  
Film Distribution ◽  
Before And After ◽  
Sand Particles ◽  
On The Road

Researchers in recent years begin to explore on tribological behavior of automotive brake squeal phenomena which covers the morphology, chemical composition, friction and wear, phase composition and third body or friction film distribution. However less effort has been made to study the tribological on the influence of small particles on brake squeal. During braking condition, both rotor and pads are exposed to road environmental particle which may affect pads surface condition. In order to assess the influence of this particle on brake squeal a series of squeal tests were performed. Silica sand grit particles with a size range between 400 to 200 μm which most available on the road surface were used in this experiment. Brake pad and disc surface characteristics were analyzed before and after squealing condition using Scanning Electron Microscope (SEM) and Energy dispersive X-ray analysis (EDX). The result shows that the silica sand particles had influence the squeal and surface behavior of the brake pad.

scholarly journals THE BITUMEN BATCHING SYSTEM'S MODERNIZATION AND ITS EFFECTIVE ANALYSIS AT THE ASPHALT MIXING PLANT

Transport ◽  
2010 ◽  
Vol 25 (3) ◽  
pp. 325-335 ◽  
Author(s):  
Justas Bražiūnas ◽  
Henrikas Sivilevičius
Keyword(s):  
Asphalt Concrete ◽  
Additive Model ◽  
Technological Parameters ◽  
Destructive Effect ◽  
The Road ◽  
Weighted Matrix ◽  
Bitumen Content ◽  
Before And After ◽  
On The Road ◽  
And Performance

Some particular aspects such as the improvement methods of technological parameters for hot bitu‐ men storage in a pipeline transport system, transportation and dosed supply to batch asphalt mixing plant (AMP) are evaluated in this paper. Bitumen in asphalt concrete binds together the material of mineral particles into a strong conglomerate of a complicated structure, capable of withstanding the destructive effect of vehicles and the factors on the road pavements. The optimal amount of bitumen determined by calculation and laboratory testing should be maintained in mix batches of hot‐mix asphalt (HMA) obtained from AMP mixer. In the periodic type of the asphalt concrete blender mass of the weighted matrix in the all merging batcher's tanks should correspond in percents equally in the HMA to the designed amount of the job‐mix formula (JMF). The bitumen batcher does not always weigh bitumen portions precisely. Their mass deviations from the amount determined by JMF and its variation impair HMA composition and performance. In addition,, an additive model for calculating the effect of factors causing the variance of bitumen content in the produced HMA mixture is presented in this current paper as well. The data on statistical evaluation of bitumen batcher's modernization performed at certain Lithuanian Enterprise are discussed. The differences in structures of reconstructed and not reconstructed bitumen batching systems (BBS) are analysed and methods of determining modernization effectiveness are presented. The effectiveness of BBS is analysed too, defining the deviations of bitumen content in subsamples, taken and extracted everyday for two seasons (before and after the batcher's modernization) of HMA mixture production from the value of JMF and comparing them to the values of tolerances. The analysis of column charts and histograms shows that the made modernization helped to increase the precision of supplying the required amount of bitumen to HMA mixture insignificantly. However, the control of BBS has been considerably increased.

Effects of Speed Bumps and Humps on Motorcycle Speed Profiles

2014 ◽  
Vol 931-932 ◽  
pp. 536-540 ◽  
Author(s):  
Wichuda Satiennam ◽  
Thaned Satiennam ◽  
Pornsiri Urapa ◽  
Tussawan Phacharoen
Keyword(s):  
Developing Countries ◽  
Developed Countries ◽  
Vehicle Speed ◽  
Passenger Car ◽  
The Road ◽  
Acceleration Rate ◽  
Major Mode ◽  
Before And After ◽  
On The Road ◽  
Speed Humps

In developed countries, the use of speed humps and bumps have evolved from extensive research and testing which been properly designed and standardized. On the contrary in developing countries, no systematic and scientific studies have been carried out on that environment, especially the study on the effects that the motorcyclists response to the humps and bumps. This study therefore reveals the riders behavior when negotiating their speed to the devices. A case study was conducted in the provincial cities of Thailand where the motorcycle was a major mode of transportation. Six locations with speed humps and bumps were selected. Vehicles passing times were simultaneously recorded at 12 points along each traffic calmed link. From these data, a speed profile for each individual vehicle and for a link could be derived. It is found that speed humps and bumps have critically different impacts on motorcycle rider and passenger car driver. The smaller size speed bumps could effectively control the rider speed but have diverse impacts on the driver. These speed differences could post more safety deficiency to the site. The effect of the device on riders behavior, however, is restricted to a short spatial range (about 20-30 m before and after the device). For the speed humps, the motorcycle speeds are quite varied depending mainly on the road terrain. It is found that the motorcyclists have significant lower acceleration rate on the upgrade terrain when compared to the passenger car. Therefore, it is important to take all these rider characteristics into considerations when design the road humps to control vehicle speed in the developing countries.

scholarly journals Integration of kinematic and dynamic mathematical models of a two-axle electric car in the problem of estimating its stability on turns

ScienceRise ◽  
2021 ◽  
pp. 23-29
Author(s):  
Vadym Horeniuk
Keyword(s):  
Mathematical Models ◽  
Control Systems ◽  
Electric Drive ◽  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Combustion Engines ◽  
The Road ◽  
On The Road ◽  
The Stability ◽  
Technological Product

Object of research: the process of movement of cars with internal combustion engines or the electric drive on a road curve. Investigation problem: assessment of the stability of cars with internal combustion engines or electric drive on a road curve and determination of conditions of its ensuring. The main scientific result. The article evaluated the stability of cars with internal combustion engines or electric drive on a road curve and determines the conditions of its ensuring using an algorithm that combines mathematical models of car movement on a road curve, synthesized based on balance equations of both kinematics and dynamics. The proposed models consider the change in speed of cars while driving on a road curve, and therefore belong to the class of differential equations. The analysis of these models allows calculating changes in time of values of limiting and critical speeds of movement of the car on a road curve. The article identifies the prospects of integration into this set of mathematical models another one, synthesized in the space of linguistic variables that characterize the uncertainty of the road surface and the degree of tire wear on different wheels of the car. The area of practical application of the research results: Automotive enterprises specializing in equipping cars with traffic control systems. Innovative technological product: A method of determining the limiting parameters of movement of the car on road curves, at which the car does not overturn while passing turns, and an algorithm for its implementation, which combines kinematic and dynamic mathematical models of car movement on the road curve. Scope of application of the innovative technological product: Equipping cars with additional control systems that assess the critical values of the traffic parameters on turns to ensure the conditions of non-overturning when the car passes these turns

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