Application of Fuzzy Moving Sliding Surface Approach for Container Cranes

Where is the abrasive or gradual removal of materials at solid surfaces? It is caused due to the interaction between the sliding surface by mechanical action. The abrasive wears can be recognised as scratches or grooves. To enhance the wear resistance suitable nanocoating is applied on the material surface for better tribological properties such as hardness and toughness. Wear resistant nanocoating is used to reduce or eradicate wear to extend the lifetime of the EN8 steel. EN8 is unalloyed medium carbon steel with better mechanical properties than mild steel and also readily machinable in any condition. The nanocoating materials such as Al2O3, TiO2, SiC, ZrO2, WS2, Si3N4 etc., are used to reduce wear and to enhance hardness and toughness on mild steel through various nanocoating techniques. This paper deals with selection of suitable nanocoating material through AHP (Analytical hierarchal process) - a multi-criteria decision-making method.

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Interaction of tungsten in dry sliding against steel under high density electric current

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2019-97-1-101-109 ◽

2019 ◽

pp. 101-109 ◽

Cited By ~ 2

Author(s):

M. I. Aleutdinova ◽

V. V. Fadin ◽

Yu. P. Mironov

Keyword(s):

Electrical Contact ◽

Analysis Data ◽

Dry Sliding ◽

Sliding Surface ◽

X Ray ◽

Sliding Surfaces ◽

Quenched Steel ◽

Sliding Electrical Contact ◽

A Current ◽

Tungsten Steel

The possibility of creating a wear-resistant dry sliding electrical contact tungsten/steel was studied. It was shown that tungsten caused severe wear of the quenched steel counterbody due to unlimited plastic flow of its surface layer at a current density up to 150 A/cm2 . This indicated the impossibility of achieving satisfactory characteristics of such a contact. Low electrical conductivity and wear resistance of the contact tungsten/steel were presented in comparison with the known high copper/steel contact characteristics under the same conditions. X-ray phase analysis data of the steel sliding surfaces made it possible to state that the cause of the unsatisfactory sliding of tungsten was the absence of the necessary concentration of FeO oxide on the sliding surface of the steel.

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Designing a scaffold for mechanistic reasoning in organic chemistry

Chemistry Teacher International ◽

10.1515/cti-2020-0001 ◽

2020 ◽

Vol 0 (0) ◽

Cited By ~ 1

Author(s):

Nicole Graulich ◽

Ira Caspari

Keyword(s):

Organic Chemistry ◽

Contrasting Cases ◽

Chemistry Teaching ◽

Surface Approach ◽

Reasoning Process ◽

Mechanistic Reasoning ◽

Key Factor ◽

Course Material ◽

Asking Questions ◽

Deep Reasoning

AbstractDesigning problems and learning activities is a key factor to initiating students’ engagement with the course material and influencing their reasoning processes. Although tasks and problems are a central part of teaching and assessments in the chemistry classroom, they may not engage students in deep reasoning or in a way that is intended through a task. Some problems may cause an algorithmic or a surface approach. Even with designing clever problems, students may not use a larger variety of chemistry ideas and connect them in meaningful ways. Here the idea of scaffolding students’ answering process comes into play. Structuring students’ reasoning process through instructional prompts or structured worksheets supports students in activating and connecting knowledge pieces in a more meaningful way and positively slows down their fast decision-making process. This paper will discuss the importance of asking questions in chemistry teaching and highlights the idea of contrasting cases, drawn from cognitive psychology, as a task design principle. In addition to having contrasting cases as a good problem format, the idea of scaffolding students’ reasoning while solving contrasting cases through the use of instructional prompts that scaffold the reasoning process will be exemplarily showcased for mechanistic reasoning in organic chemistry.

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