Life and Reliability of Elastomer Products. Developments in Elastomer Degradation and Stabilization.

Dielectric Elastomers Conductive Elastomer Insulating Elastomer

modularity of reading comprehension in multiple-choice cloze procedure and reliability fluctuation

هدف این رساله تحقیق در مورد یافتن ارتباط بین واحدهای درک مطلب (از قبیل پروسه واژگانی، پروسه ساختاری و پروسه تفسیر معنایی) از طریق تست کلوز چهار چوابی در بین دانشجویان سال آخر رشته زبان انگلیسی میباشد. در مرحله اول از 150 دانشجو (80 مونث و 70 مذکر) از بین دانشجویان کارشناسی و کارشناسی ارشد دانشگاههای علامه طباطبائی، دانشگاه شهید بهشتی و دانشگاه آزاد اسلامی واحد شمال تست نلسون (450 دی) گرفته شد. ...

Nematic elastomer actuators

In this seminar, the liquid crystal elastomers (LCEs) and their building blocks – liquid crystals and polymers are presented. The specific rod-like molecular shape of liquid crystals forces LCEs to form a special molecular distribution of the underlying polymer network. This allows them expand up to 400 % with temperature, which could be used in applications. The physics of this spontaneous dis...

Mechanical Strength Improvement of Mud Motor’s Elastomer by Nano Clay and Prediction the Working Life via Strain Energy

In directional drilling, the most important thing that leads to pulling out the drill string is end of mud motor working life. Considering the working conditions of down hole mud motors; increasing the mechanical properties of their stator’s elastomer is crucial. Some attempts were done to increase the motor performance through geometrical changes but lack of material improvement is significant...

Helical dielectric elastomer actuators

This paper presents a new type of contractile polymer-based electromechanical linear actuator. The device belongs to the class of dielectric elastomer actuators, which are typically capable of undergoing large deformations induced by an applied electric field. It is based on a novel helical configuration, suitable for the generation of electrically driven axial contractions and radial expansion...