Performance of SBR and BR Tread Compounds as a Function of Carbon Black Dispersion, Surface Chemistry, and Structure

1969 ◽  
Vol 42 (3) ◽  
pp. 700-713 ◽  
Author(s):  
C. E. Scott ◽  
V. Chirico
Keyword(s):  
Wear Resistance ◽  
Carbon Black ◽  
Strain Energy ◽  
Normal Structure ◽  
Chain Structure ◽  
Dispersion Surface ◽  
High Level ◽  
Oxygen Functionality ◽  
Carbon Black Dispersion

Abstract A study has been made of the effect of carbon black dispersion, oxygen volatile, and extremes in chain structure development on vulcanizate properties and treadwear. The effect of poorly dispersed carbon black is to reduce wear resistance, tensile strength, strain energy, and groove cracking resistance. Other vulcanizate properties are not as noticeably affected. The role of oxygen functionality in reinforcement was investigated in a series of oxidation and devolatilization experiments. Added oxygen functionality of a critical amount reduces modulus, strain energy and treadwear resistance. Attempts to raise these properties through added acceleration results in greatly reduced treadwear. Carbon black-elastomer adhesion is indicated once again as the sine qua non of wear resistance. Carbon blacks possessing an unusually high level of reticulate chain structure require a lower level of chemical crosslinking than carbons of normal structure level for maximum treadwear resistance. This finding is consistent with a reinforcement theory involving stress dissipation by transfer to the carbon-elastomer interface, where relief occurs by slippage over the friction surface.

A Quantitative Study of the Carbon Black Reinforcement System for Tire Tread Compounds

1979 ◽  
Vol 52 (4) ◽  
pp. 748-763 ◽  
Author(s):  
A. G. Veith ◽  
V. E. Chirico
Keyword(s):  
Wear Resistance ◽  
Carbon Black ◽  
Surface Area ◽  
High Performance ◽  
Materials Science ◽  
Normal Structure ◽  
Wear Testing ◽  
Reinforcement System ◽  
Wear Rates ◽  
Carbon Blacks

Abstract This comprehensive program clearly shows the influence of the four defined reinforcement system variables. The tread wear testing conducted over an extremely wide severity range illustrates how the influence of each variable or factor changes as the tire use of test severity is changed. The quantitative influence of the four variables is best illustrated by the index severity gradient, while the index range serves as a quick indicator. The influence of each factor of the reinforcement system increases as general test severity is increased. Carbon blacks with high structure and surface area are substantially superior to blacks with normal structure and surface area at the higher test severities. At the higher general severities, increased oil content produces higher wear rates. At any given severity level, the rate of wear passes through a minimum as carbon black level is increased. The carbon black content at this minimum wear rate shifts to higher values as general severity is raised. Test results at a series of specific cornering force levels (0.10–0.30 g range) indicate that the relative wear of typical tread compounds demonstrates crossovers of index values. Compounds that show superior wear resistance compared to a reference compound at high cornering severities often show inferior wear resistance at low cornering severities. Therefore, for maximum tread life or wear resistance, the reinforcement system with any tread rubber or rubber blend must be carefully adjusted to the anticipated level of tire use severity. The introduction of improved-technology carbon blacks with increased rubber-black interaction that is promoted by high DBP and EMA levels is a substantial advancement in rubber materials science and is most important for the production of high-performance long-treadlife tires.

Characterization of Carbon Black Structure by Mercury Penetration

1971 ◽  
Vol 44 (3) ◽  
pp. 805-813 ◽  
Author(s):  
L. Moscou ◽  
S. Lub ◽  
O. K. F. Bussemaker
Keyword(s):  
Carbon Black ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Mercury Porosimetry ◽  
Normal Structure ◽  
Break Point ◽  
Chain Structure ◽  
Structure Index ◽  
High Structure

Abstract The determination of the chain-structure of carbon black by mercury porosimetry is described. It is shown that each type of black has its own porosity curve, depending on specific surface area and degree of structure. An absolute measure for the degree of structure is proposed: The “Structure Index”, calculated from the break point in the porosity curve, the specific surface area and the density of the black. Structure Index for structureless blacks is 1.0 – 1.1, for low structure blacks 1.7 – 1.9, for normal structure blacks 2.3 – 2.4 and for high structure blacks 2.7 – 2.8.

Effects of Carbon Black Structure on Tire Tread Wear

1961 ◽  
Vol 34 (1) ◽  
pp. 43-56 ◽  
Author(s):  
T. D. Bolt ◽  
E. M. Dannenberg
Keyword(s):  
Wear Resistance ◽  
Carbon Black ◽  
Primary Particle ◽  
Normal Structure ◽  
Significant Loss ◽  
Wear Performance ◽  
Furnace Process ◽  
Service Conditions ◽  
Mixing Techniques ◽  
Heat Buildup

Abstract Oil furnace process carbon blacks have been produced which differ widely in the extent of their primary chainlike aggregation. The effect of the carbon black structure on rubber properties and road wear was evaluated in oil-extended SBR passenger tire tread compounds. The decrease in primary particle aggregation increases the tendency to form strong, dense, secondary agglomerates which require mixing techniques designed to insure that they are well dispersed. The behavior in rubber of a series of oil furnace blacks differing primarily in their structure is most apparent in processing, shrinkage, modulus and hardness. There are small effects on rebound and flex cracking resistance but no significant effects on tensile strength and heat buildup. Carbon black structure can be reduced to some extent without encountering significant loss in road wear resistance under normal wearing conditions. Some decrease in road wear performance occurred under very severe road test conditions. The use of higher black loadings of the normal structure blacks gave good wear resistance under both normal and severe service conditions.

Searching for ‘success’: generation, gender and onward migration in the Iranian diaspora

2017 ◽  
Vol 14 (1) ◽  
pp. 101-112 ◽  
Author(s):  
Melissa Kelly
Keyword(s):  
Life History ◽  
Young Age ◽  
Onward Migration ◽  
Social Fields ◽  
Transnational Social Fields ◽  
High Level ◽  
Iranian Diaspora

This article uses the concepts of ‘transnational social fields’ and ‘habitus’ to explore the multifaceted role families play in shaping the aspirations of onward migrating youth. The article draws on biographical life history interviews conducted with the children of Iranian migrants who were raised in Sweden but moved to London, UK as adults. The findings of the study suggest that from a young age, all the participants were pressured by their parents to perform well academically, and to achieve high level careers. These goals were easier to achieve in London than in Sweden for several reasons. Interestingly, however, participants’ understandings of what constituted success and their motivations for onward migration were nuanced and varied considerably by gender. The study contributes to an understanding of the role of multi-sited transnational social fields in shaping the aspirations of migrant youths, as well as the strategies taken up by these migrants to achieve their goals.

Decision making power of college girls in relation to clothing

2018 ◽  
Vol 9 (01) ◽  
Author(s):  
Parul Gill ◽  
Poonam Malik ◽  
Pankaj Gill
Keyword(s):  
Decision Making ◽  
Satisfaction Level ◽  
College Going ◽  
Level Of Satisfaction ◽  
High Level ◽  
Garment Design ◽  
Structured Questionnaire

The present study was undertaken to explore the decision making patterns of college girls in relation to clothing and their satisfaction level with these decision making patterns. Thirty under graduate college girls from Panipat city were approached to record their responses regarding decision making in relation to clothing and satisfaction level through a well structured questionnaire. It was found that most of the girls (56.66%) themselves made the decisions about the type of garment (Indian, western or both) they wear and majority of girls (70%) were highly satisfied with this decision making. Parents performed the role of buyers for their college going daughters' garments in most of the cases (63.33%) and the 73.33% girls had high level of satisfaction with this. In most of the cases (60%) the decision about the garment design was made by the girls themselves and they were highly satisfied with it. Keywords: clothing, college, girls, decision making.

Сирия (аш-Шам) в системе османских владений (XVI – начало XX в.)

2019 ◽  
Author(s):  
D.R. Zhantiev
Keyword(s):  
Ottoman Empire ◽  
19Th Century ◽  
Social Mechanisms ◽  
Checks And Balances ◽  
Local Elites ◽  
The Balkans ◽  
The Face ◽  
High Level ◽  
The 19Th Century

Аннотация В статье рассматривается роль и место Сирии (включая Ливан и Палестину) в системе османских владений на протяжении нескольких веков от османского завоевания до периода правления султана Абдул-Хамида II. В течение четырех столетий османского владычества территория исторической Сирии (Билад аш-Шам) была одним из важнейших компонентов османской системы и играла роль связующего звена между Анатолией, Египтом, Ираком и Хиджазом. Необходимость ежегодной организации хаджа с символами султанской власти и покровительства над святынями Мекки и Медины определяла особую стратегическую важность сирийских провинций Османской империи. Несмотря на ряд серьезных угроз во время общего кризиса османской государственности (конец XVI начало XIX вв.), имперскому центру удалось сохранить контроль над Сирией путем создания сдержек и противовесов между местными элитами. В XIX в. и особенно в период правления Абдул- Хамида II (18761909 гг.), сохранение Сирии под османским контролем стало вопросом существования Османской империи, которая перед лицом растущего европейского давления и интервенции потеряла большую часть своих владений на Балканах и в Северной Африке. Задача укрепления связей между имперским центром и периферией в сирийских вилайетах в последней четверти XIX в. была в целом успешно решена. К началу XX в. Сирия была одним из наиболее политически спокойных и прочно связанных со Стамбулом регионов Османской империи. Этому в значительной степени способствовали довольно высокий уровень общественной безопасности, развитие внешней торговли, рост образования и постепенная интеграция местных элит (как мусульман, так и христиан) в османские государственные и социальные механизмы. Положение Сирии в системе османских владений показало, что процесс ослабления и территориальной дезинтеграции Османской империи в эпоху реформ не был линейным и наряду с потерей владений и влияния на Балканах, в азиатской части империи в течение XIX и начала XX вв. происходил параллельный процесс имперской консолидации.Abstract The article examines the role and place of Greater Syria (including Lebanon and Palestine) in the system of Ottoman possessions over several centuries from the Ottoman conquest to the period of the reign of Abdul Hamid II. For four centuries of Ottoman domination, the territory of historical Syria (Bilad al-Sham) was one of the most important components in the Ottoman system and played the role of a link between Anatolia, Egypt, Iraq and Hijaz. The need to ensure the Hajj with symbols of Sultan power and patronage over the shrines of Mecca and Medina each year determined the special strategic importance of the Syrian provinces of the Ottoman Empire. Despite a number of serious threats during the general crisis of the Ottoman state system (late 16th early 19th centuries), the imperial center managed to maintain control over Syria by creating checks and balances between local elites. In the 19th century. And especially during the reign of Abdul Hamid II (18761909), keeping Syria under Ottoman control became a matter of existence for the Ottoman Empire, which, in the face of increasing European pressure and intervention, lost most of its possessions in the Balkans and North Africa. The task of strengthening ties between the imperial center and the periphery in Syrian vilayets in the last quarter of the 19th century was generally successfully resolved. By the beginning of the 20th century, Syria was one of the most politically calm and firmly connected with Istanbul regions of the Ottoman Empire. This was greatly facilitated by a fairly high level of public safety, the development of foreign trade, the growth of education and the gradual integration of local elites (both Muslims and Christians) into Ottoman state and social mechanisms. Syrias position in the system of Ottoman possessions clearly showed that the process of weakening and territorial disintegration of the Ottoman Empire during the era of reform was not linear, and along with the loss of possessions and influence in the Balkans, in the Asian part of the empire during the 19th and early 20th centuries there was a parallel process of imperial consolidation.

Changing Role of Agriculture in Income and Employment, and Trends of Agricultural Worker Productivity in Indian States

2020 ◽  
pp. 183-189
Keyword(s):  
Green Revolution ◽  
Positive Trend ◽  
Worker Productivity ◽  
Indian States ◽  
Agricultural Worker ◽  
The Sixties ◽  
High Level ◽  
The Cost ◽  
Changing Role

The productivity of land has been often discussed and deliberated by the academia and policymakers to understand agriculture, however, very few studies have focused on the agriculture worker productivity to analyze this sector. This study concentrates on the productivity of agricultural workers from across the states taking two-time points into consideration. The agriculture worker productivity needs to be dealt with seriously and on a time series basis so that the marginal productivity of worker can be ascertained but also the dependency of worker on agriculture gets revealed. There is still disguised unemployment in all the states and high level of labour migration, yet most of the states showed the dependency has gone down. Although a state like Madhya Pradesh is doing very well in terms of income earned but that is at the cost of increased worker power in agriculture as a result of which, the productivity of worker has gone down. States like Mizoram, Meghalaya, Nagaland and Tripura, though small in size showed remarkable growth in productivity and all these states showed a positive trend in terms of worker shifting away from agriculture. The traditional states which gained the most from Green Revolution of the sixties are performing decently well, but they need to have the next major policy push so that they move to the next orbit of growth.

Effect of cluster-gradient architecture of nanostructured topocomposites on features of tribointeraction with heterophased material

2020 ◽  
pp. 130-135
Author(s):  
D.N. Korotaev ◽  
K.N. Poleshchenko ◽  
E.N. Eremin ◽  
E.E. Tarasov
Keyword(s):  
Wear Resistance ◽  
Titanium Alloy ◽  
Energy Dissipation ◽  
Phase Structure ◽  
Diffusion Processes ◽  
Structural Phase ◽  
High Wear Resistance ◽  
Wear Characteristics ◽  
And Diffusion

The wear resistance and wear characteristics of cluster-gradient architecture (CGA) nanostructured topocomposites are studied. The specifics of tribocontact interaction under microcutting conditions is considered. The reasons for retention of high wear resistance of this class of nanostructured topocomposites are studied. The mechanisms of energy dissipation from the tribocontact zone, due to the nanogeometry and the structural-phase structure of CGA topocomposites are analyzed. The role of triboactivated deformation and diffusion processes in providing increased wear resistance of carbide-based topocomposites is shown. They are tested under the conditions of blade processing of heat-resistant titanium alloy.

Methyl mercury in the dutch rhine delta

1994 ◽  
Vol 30 (10) ◽  
pp. 213-219 ◽  
Author(s):  
Hendrik Pieters ◽  
Victor Geuke
Keyword(s):  
Suspended Matter ◽  
Methyl Mercury ◽  
Mercury Contamination ◽  
Benthic Organisms ◽  
Considerable Decrease ◽  
Continuous Sedimentation ◽  
Highly Correlated ◽  
High Level ◽  
Almost All

Samples of yellow eel from various locations in the Dutch Rhine area have been analyzed for trend monitoring of mercury since 1977. In the western Rhine delta mercury levels in eels have hardly changed since the seventies, whereas in the eastern part of the Dutch Rhine area a considerable decrease of mercury concentrations in eel has occurred. Because of continuous sedimentation of contaminated suspended matter transported from upstream regions, accumulation rates and concentrations of mercury in eel in the western Rhine delta remained at a relatively high level. Analyses of methyl mercury in biota have been performed to elucidate the role of methyl mercury in the mercury contamination of the Dutch Rhine ecosystem. Low percentages of methyl mercury were observed in zooplankton (3 to 35%). In benthic organisms (mussels) percentages of methyl mercury ranged from 30 to 57%, while in fish species and liver of aquatic top predator birds almost all the mercury was present in the form of methyl mercury (> 80%). During the period 1970-1990 mercury concentrations of suspended matter in the eastern Rhine delta have drastically decreased. These concentrations seemed to be highly correlated with mercury concentrations of eel (R = 0.84). The consequences of this relation are discussed.

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