Strain-Dependent Dynamic Properties of Carbon-Black Reinforced Vulcanizates. II. Elastomer Blends

1975 ◽  
Vol 48 (1) ◽  
pp. 89-96 ◽  
Author(s):  
A. K. Sircar ◽  
T. G. Lamond
Keyword(s):  
Carbon Black ◽  
Dynamic Properties ◽  
Three Dimensional ◽  
Individual Characteristics ◽  
The Individual ◽  
Dispersing Medium ◽  
Polymeric Medium ◽  
Strain Dependent ◽  
Filler Structure ◽  
Predominant Effect

Abstract The three-dimensional aggregated structure of carbon black in elastomer blends behaves in a similar fashion to that of the individual elastomers. The elastomer seems to act merely as a dispersing medium. The properties of the rubber reflect the structural effects of the filler superimposed upon the elastomer itself. The elastomer molecules no doubt retain their individual characteristics of rotation of bonds which govern the stiffness of the molecule. However, the superimposed carbon-black network exerts the predominant effect, as far as the low-strain dynamic characteristics are concerned. The polymeric medium seems to influence this interaction by determining the magnitude of agglomeration and distribution of black in the phases, but does not have visible influence on the overall characteristics of the carbon-black networks. In this respect blends of two elastomers behave as a single elastomer. The importance of the present work is that the strain-dependent dynamic properties of blends of elastomers are very similar to those of single elastomers. In tires and antivibration applications, the strain imposed is usually less than 10%. More and more blends of elastomers are being used for these applications. The filler structure and its breakdown at these strains have an important contribution to hardness, modulus, and hysteresis of these compounds.

Carbon Black Structure in Rubber

1963 ◽  
Vol 36 (1) ◽  
pp. 147-155 ◽  
Author(s):  
A. R. Payne ◽  
W. F. Watson
Keyword(s):  
Carbon Black ◽  
Dynamic Properties ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Organic Liquids ◽  
Carbon Blacks ◽  
Metal Soaps ◽  
Dispersing Medium ◽  
Structural Carbon ◽  
Filler Structure

Abstract Some of the properties of carbon blacks in rubber are ascribed to its “structure”. This paper presents results on the sinusoidal dynamic straining of rubber/carbon black vulcanizates over an amplitude range including strains less than 0.1% and suggests that an elucidation of structure effects and the nature of the structure underlying them is forthcoming from these results. The dynamic properties are profoundly modified by special processing. Heat treatment of stocks containing structural carbon blacks and particularly the use of N-methyl-N,4-dinitrosoaniline can greatly reduce structure effects. They are absent with attrited blacks. Similar results have been obtained with silica fillers, for which certain metal soaps virtually eliminate structure effects. Structure effects are shown to be not essentially related to the rubber network, including the type of rubber, but to be due to a physical, three-dimensional structure of the filler itself within the rubber; the rubber acts merely as a dispersing medium and a matrix to allow the filler structure to re-form after breakdown. These changes of the filler structure are often the major cause of hysteresis at low extensions. Mixtures of carbon black and organic liquids demonstrate the existence and properties of the physical carbon black structure in absence of rubber. The properties of the rubber have the structural effects of the filler superimposed upon them.

scholarly journals Global X-tream Index and its Partial Parameters for Identifying the Level of Potential Individual Characteristics in the Challenging Conditions of a Modern Corporate and Security Environment

2019 ◽  
Vol 11 (12) ◽  
pp. 3325 ◽  
Author(s):  
David Ullrich ◽  
Jiří Koleňák ◽  
Eva Ambrozová ◽  
Vratislav Pokorný ◽  
František Milichovský
Keyword(s):  
Readiness To Change ◽  
Current Knowledge ◽  
Three Dimensional ◽  
Individual Characteristics ◽  
Personality Dimension ◽  
Security Environment ◽  
Professional Managers ◽  
Personal Fitness ◽  
Definition Of ◽  
The Individual

The contribution of this paper focuses on identifying the personality potential and sources of professional managers that are crucial for the effective management of challenging situations. The contribution introduces the current knowledge of connatural management (CNM) as part of cognitive management, which were identified as key multi-parametric dimensions of personal fitness. The individual dimensions represent the indicators of the quality of an individual’s condition. The first one is the personality dimension, which provides information about individual integrity, situational settings, ambition, the tendency of an individual toward risk, and readiness to change. Second, the mental–cognitive dimension relates to the individual’s potential for critical, creative, and systemic thinking. It conveys information about the ability to accept a change and proactively adapt to its consequences. Lastly, the psycho-physical dimension concerns the interaction of physical and mental processes, states, and phenomena. The main objective of the research was to determine the Global X-tream index, which is applicable for the prompt identification of the qualities of human resources for a specific corporate HR system. The study consisted of 236 respondents, who graduated and successfully completed special courses with applied X-tream methodology. It enables the creation of conditions that enable detecting and evaluating the above-mentioned basic three-dimensional and multi-parametric indicators related to the performance of individuals in a corporate environment. The paper introduces the individual indices, which were used as a basis for the definition of the global X-tream index.

Low Strain Dynamic Properties of Filled Rubbers

1971 ◽  
Vol 44 (2) ◽  
pp. 440-478 ◽  
Author(s):  
A. R. Payne ◽  
R. E. Whittaker
Keyword(s):  
Carbon Black ◽  
Dynamic Properties ◽  
Fatigue Behavior ◽  
Van Der Waals ◽  
Three Dimensional ◽  
Solid Particles ◽  
Spherical Particles ◽  
Filled Rubber ◽  
Secondary Network ◽  
Filled Rubbers

Abstract Carbon black does not exist as single spherical particles but forms itself into a rodlike primary structure. These rodlike structures then form into an aggregated secondary network. This secondary network is believed to be held together by Van der Waals-London attraction forces. The decrease in shear modulus of filled rubber vulcanizates with strain is due almost certainly to these secondary forces. Special mixing techniques such as attrition of the carbon black, increased time of mixing, or the addition of chemical promoters which aim at dispersing the carbon black within the mix better are shown to decrease the value of G′0−G′∞. The absence of any modulus change with strain for unfilled vulcanizates and secondly the little change observed in values of G′0−G′∞ with increasing vulcanization of the rubber when containing the same amount of carbon black confirms that the decrease in modulus with strain amplitude is in no way associated with the gum phase of the filled vulcanizate. The similarity in behavior of carbon black filled rubbers with clay/water and clay/rubber systems indicates that the decrease in modulus with amplitude is due to the breakdown of the three dimensional filler aggregates. A number of rheological studies on clay systems has confirmed that clay particles form into rigid three dimensional structures when dispersed in a medium. Evidence for the aggregated filler structure to be held together by Van der Waals-London attraction forces comes from the reasonable agreement between the experimental values for the forces required to breakdown the carbon black aggregates in paraffin oil and the forces calculated from Van den Tempel's model for flocculated solid particles in a liquid. The successful application of a domain model to the hysteretical behavior exhibited by carbon black filled vulcanizates at low strains indicates that the carbon black structure breaks down under stress but reforms to the original state when the stress is removed. This conclusion is also supported by the similarity in behavior between filled rubbers and a dendritic crystal structure of PBNA in rubber. Under the optical microscope the PBNA is seen to break down and reform under a stress-strain cycle. The breakdown and reformation of this secondary aggregated carbon black structure increases the hysteresis in filled rubber vulcanizates. Other sources of hysteresis include viscoelasticity of the polymer, crystallization, stress-softening, and changes in network structure (e.g., breakage of weak crosslinks). These mechanisms have been discussed in depth in previous publications. Recent work has shown, however, that the strength of a rubber is dependent on the combined effect of the different hysteretical mechanisms. The breakdown and reformation of the carbon black structure at low strains in filler reinforced rubbers therefore not only affects the heat build up, transmissibility, and fatigue behavior but also influences the failure properties of the filled vulcanizate.

Strain-Dependent Dynamic Properties of Carbon-Black Reinforced Vulcanizates. I. Individual Elastomers

1975 ◽  
Vol 48 (1) ◽  
pp. 79-88 ◽  
Author(s):  
A. K. Sircar ◽  
T. G. Lamond
Keyword(s):  
Carbon Black ◽  
Dynamic Properties ◽  
Carbon Black Particle ◽  
Structural Elements ◽  
Black Particle ◽  
Tan Δ ◽  
The Relationship ◽  
Storage Units ◽  
Strain Dependent ◽  
Transient Structure

Abstract The degree of carbon—black particle aggregation (transient structure) in conventional vulcanizates varies with the nature of the elastomers. This is revealed by the variation of (Gm′−G∞ƒ′), which is a measure of the transient structure. The relationship between Gm″ and (Gm′−G∞ƒ′) as well as that between strain work and normalized modulus show similarity to earlier work in which the polymer type was not varied. This suggests that carbon-black structural elements act as energy storage units and are of the same type in all these polymers. While the decrease of in-phase modulus is primarily caused by carbon-black particle units, tan δ reflects also the effect of the polymeric matrix.

Three-Dimensional Virtual Environment and NPC

2016 ◽  
pp. 510-536 ◽  
Author(s):  
Fabricio Herpich ◽  
Felipe Becker Nunes ◽  
Gleizer Bierhalz Voss ◽  
Roseclea Duarte Medina
Keyword(s):  
Knowledge Base ◽  
Virtual Environments ◽  
Virtual Environment ◽  
Intelligent Agents ◽  
Three Dimensional ◽  
Intelligent Agent ◽  
Learning Objects ◽  
Individual Characteristics ◽  
Computer Networking ◽  
The Individual

The use of intelligent agents aware of the individual characteristics and context of students, allow to offer a suitable support to the real requirements. Allied to this, the implementation of these agents in the three-dimensional virtual environments, tend to transcend the existing potential in the interactions with the learning objects it contains and also to expand the alternatives of building the students' knowledge. Throughout this chapter it will be presented the development of intelligent agent called ELAI, by using the NPC strategy on the virtual world platform OpenSimulator. The ELAI provides support for teaching Computer Networking (CN), being sensitive to the context of learners to their level of expertise. In order to maximize the flexibility of interactions between the student, through the student's avatar and the NPC, an interconnection with a chatterbot was established, whose knowledge base was increased by files in AIML inherent to the topic of CN.

Three-Dimensional Virtual Environment and NPC

2020 ◽  
pp. 912-938
Author(s):  
Fabricio Herpich ◽  
Felipe Becker Nunes ◽  
Gleizer Bierhalz Voss ◽  
Roseclea Duarte Medina
Keyword(s):  
Knowledge Base ◽  
Virtual Environments ◽  
Virtual Environment ◽  
Intelligent Agents ◽  
Three Dimensional ◽  
Intelligent Agent ◽  
Learning Objects ◽  
Individual Characteristics ◽  
Computer Networking ◽  
The Individual

The use of intelligent agents aware of the individual characteristics and context of students, allow to offer a suitable support to the real requirements. Allied to this, the implementation of these agents in the three-dimensional virtual environments, tend to transcend the existing potential in the interactions with the learning objects it contains and also to expand the alternatives of building the students' knowledge. Throughout this chapter it will be presented the development of intelligent agent called ELAI, by using the NPC strategy on the virtual world platform OpenSimulator. The ELAI provides support for teaching Computer Networking (CN), being sensitive to the context of learners to their level of expertise. In order to maximize the flexibility of interactions between the student, through the student's avatar and the NPC, an interconnection with a chatterbot was established, whose knowledge base was increased by files in AIML inherent to the topic of CN.

Semi-automated methods for 3-D reconstruction of macromolecular complexes

1995 ◽  
Vol 53 ◽  
pp. 42-43
Author(s):  
B. Carragher ◽  
M. Whittaker
Keyword(s):  
Three Dimensional ◽  
Time Saving ◽  
Macromolecular Complexes ◽  
Symmetry Properties ◽  
Dimensional Reconstruction ◽  
Experienced Operator ◽  
Projection Images ◽  
The Individual ◽  
Natural Symmetry

Techniques for three-dimensional reconstruction of macromolecular complexes from electron micrographs have been successfully used for many years. These include methods which take advantage of the natural symmetry properties of the structure (for example helical or icosahedral) as well as those that use single axis or other tilting geometries to reconstruct from a set of projection images. These techniques have traditionally relied on a very experienced operator to manually perform the often numerous and time consuming steps required to obtain the final reconstruction. While the guidance and oversight of an experienced and critical operator will always be an essential component of these techniques, recent advances in computer technology, microprocessor controlled microscopes and the availability of high quality CCD cameras have provided the means to automate many of the individual steps.During the acquisition of data automation provides benefits not only in terms of convenience and time saving but also in circumstances where manual procedures limit the quality of the final reconstruction.

THE METHODS OF DEVELOPING COMPUTATIONAL THINKING OF STUDENTS WHILE STUDYING THE COURSE "NUMERICAL METHODS" BASED ON BLENDED LEARNING

2019 ◽  
pp. 34-41
Author(s):  
M. M. Klunnikova
Keyword(s):  
Numerical Methods ◽  
Blended Learning ◽  
Computational Thinking ◽  
Individual Characteristics ◽  
Diagnostic Model ◽  
Mathematics Students ◽  
Professional Activities ◽  
Cognitive Component ◽  
Professional Field ◽  
The Individual

The work is devoted to the consideration of improving the quality of teaching students the discipline “Numerical methods” through the development of the cognitive component of computational thinking based on blended learning. The article presents a methodology for the formation of computational thinking of mathematics students, based on the visualization of algorithmic design schemes and the activation of the cognitive independence of students. The characteristic of computational thinking is given, the content and structure of computational thinking are shown. It is argued that a student with such a mind is able to manifest himself in his professional field in the best possible way. The results of the application of the technique are described. To determine the level of development of the cognitive component of computational thinking, a diagnostic model has been developed based on measuring the content, operational and motivational components. It is shown that the proposed method of developing computational thinking of students, taking into account the individual characteristics of students’ thinking, meaningfully based on the theoretical and practical aspects of studying the discipline, increases the effectiveness of learning the course “Numerical methods”. The materials of the article are of practical value for teachers of mathematical disciplines who use information and telecommunication technologies in their professional activities.

MEDIA SOCIALIZATION OF PERSONALITY IN THE CONTEXT OF INMUTATION IN THE MASS MEDIA

2021 ◽  
pp. 104-109
Author(s):  
Chernysh O.O.
Keyword(s):  
Mass Media ◽  
Negative Impact ◽  
Effective Interaction ◽  
Individual Characteristics ◽  
Media Culture ◽  
Active Growth ◽  
Media Space ◽  
The Media ◽  
The Individual

The urgency of the researched problem is connected with the growing role of mass media in modern conditions leads to change of values and transformation of identity of the person. The active growth of the role of the media, their influence on the formation and development of personality leads to the concept of “media socialization” and immutation in the media. The aim of the study is to outline the possibilities of the process of media socialization in the context of immutation in the media. The methods of our research are: analysis of pedagogical, psychological, literature, synthesis, comparison, generalization. The article analyzes the views of domestic and foreign scientists on the problem of immutation in the media and the transformation of the information space. In the context of the mass nature of the immutation of society, the concept of “media socialization” becomes relevant, which is the basis for reducing the negative impact of the media on the individual.The author identifies the lack of a thorough study of the concept of “media socialization” in modern scientific thought. Thus, media socialization is associated with the transformation of traditional means of socialization, and is to assimilate and reproduce the social experience of mankind with the help of new media.The article analyzes the essence of the concepts “media space”, “mass media” and “immutation”. The influence of mass media on the formation and development of the modern personality is described in detail.The study concluded that it is necessary to form a media culture of the individual, to establish safe and effective interaction of young people with the modern media system, the formation of media awareness, media literacy and media competence in accordance with age and individual characteristics for successful media socialization. The role of state bodies in solving the problem of media socialization of the individual was also determined. It is determined that the process of formation of media culture in youth should take place at the level of traditional institutions of socialization of the individual.The author sees the prospect of further research in a detailed analysis and study of the potential of educational institutions as an institution and a means of counteracting the mass nature of the immutation of society.Key words: immutation, media socialization, mass media, media space, information.

Phonetic iconicity in the evaluative morphology of a sample of Indo-European, Niger-Congo and Austronesian languages

2010 ◽  
Vol 3 (2) ◽  
pp. 156-180 ◽  
Author(s):  
Renáta Gregová ◽  
Lívia Körtvélyessy ◽  
Július Zimmermann
Keyword(s):  
Three Dimensional ◽  
Sound Symbolism ◽  
Three Dimensional Model ◽  
Austronesian Languages ◽  
Place Of Articulation ◽  
European Languages ◽  
Phonetic Symbolism ◽  
The Individual ◽  
Core Vocabulary

Universals Archive (Universal #1926) indicates a universal tendency for sound symbolism in reference to the expression of diminutives and augmentatives. The research ( Štekauer et al. 2009 ) carried out on European languages has not proved the tendency at all. Therefore, our research was extended to cover three language families – Indo-European, Niger-Congo and Austronesian. A three-step analysis examining different aspects of phonetic symbolism was carried out on a core vocabulary of 35 lexical items. A research sample was selected out of 60 languages. The evaluative markers were analyzed according to both phonetic classification of vowels and consonants and Ultan's and Niewenhuis' conclusions on the dominance of palatal and post-alveolar consonants in diminutive markers. Finally, the data obtained in our sample languages was evaluated by means of a three-dimensional model illustrating the place of articulation of the individual segments.

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