scholarly journals Multiple phoretic mechanisms in the self-propulsion of a Pt-insulator Janus swimmer

2017 ◽  
Vol 828 ◽  
pp. 318-352 ◽  
Author(s):  
Yahaya Ibrahim ◽  
Ramin Golestanian ◽  
Tanniemola B. Liverpool
Keyword(s):  
Coating Thickness ◽  
Theoretical Study ◽  
Reaction Rates ◽  
The Self ◽  
Janus Particles ◽  
Potential Significance

We present a detailed theoretical study which demonstrates that electrokinetic effects can also play a role in the motion of metallic-insulator spherical Janus particles. Essential to our analysis is the identification of the fact that the reaction rates depend on Pt-coating thickness and that the thickness of coating varies from pole to equator of the coated hemisphere. We find that their motion is due to a combination of neutral and ionic-diffusiophoretic as well as electrophoretic effects whose interplay can be changed by varying the ionic properties of the fluid. This has great potential significance for optimizing performance of designed synthetic swimmers.

scholarly journals Elephant trunks form joints to squeeze together small objects

2018 ◽  
Vol 15 (147) ◽  
pp. 20180377
Author(s):  
Jianing Wu ◽  
Yichao Zhao ◽  
Yunshu Zhang ◽  
David Shumate ◽  
Stephanie Braccini Slade ◽  
...  
Keyword(s):  
Granular Materials ◽  
Theoretical Study ◽  
Robotic Manipulators ◽  
Force Sensor ◽  
The Self ◽  
Applied Force ◽  
African Elephants ◽  
Food Items ◽  
Unique Method ◽  
Push Down

Wild African elephants are voracious eaters, consuming 180 g of food per minute. One of their methods for eating at this speed is to sweep food into a pile and then pick it up. In this combined experimental and theoretical study, we elucidate the elephant’s unique method of picking up a pile of food by compressing it with its trunk. To grab the smallest food items, the elephant forms a joint in its trunk, creating a pillar up to 11 cm tall that it uses to push down on food. Using a force sensor, we show the elephant applies greater force to smaller food pieces, in a manner that is required to solidify the particles into a lump solid, as calculated by Weibullian statistics. Elephants increase the height of the pillar with the force required, achieving up to 28% of the applied force using the self-weight of the pillar alone. This work shows that elephants are capable of modulating the force they apply to granular materials, taking advantage of their transition from fluid to solid. In the future, heavy robotic manipulators may also form joints to compress and lift objects together.

scholarly journals Self-realisation, self-actualisation and self-efficacy concepts theoretical analysis

2021 ◽  
Vol 27 (2) ◽  
pp. 7-15
Author(s):  
Tatyana Petrovna Opekina ◽  
Natalya Sergeevna Shipova
Keyword(s):  
Comparative Analysis ◽  
Theoretical Analysis ◽  
Goal Setting ◽  
Self Efficacy ◽  
Theoretical Study ◽  
The Self ◽  
Social Orientation ◽  
Similarities And Differences ◽  
The Individual ◽  
External Forces

This article presents the results of a theoretical study of self-realisation, self-actualisation and self-efficacy phenomena. The main aspects of understanding and correlating these phenomena in classical and modern Russian and foreign psychology are described. The highlighted concepts related to the phenomenon of self-realisation, both in the field of psychology and pedagogy. The similarities and differences of the self-realisation, self-actualisation, self-efficacy phenomena, as well as their correlation and comparison are presented. A comparative analysis of the studied concepts is given. According to the results of the theoretical analysis, the processes of self-realisation and self-actualisation are based on the inner motivation of a person to grow, develop personality, realise its potential. Both of these processes, due to their subjectivity, are difficult to observe and measure from the outside. We have highlighted the main differences, consisting in a greater awareness and orderliness of the process of self-realisation, as well as its predominantly "social" orientation, while self-actualisation is often associated with the struggle with external forces, the desire for self-realisation is rather approved and supported by the society. The concepts of self-realisation and self-efficacy are united by their inherent representation in the external plane of the life of the individual, as well as awareness, activity, goal-setting, and an orientation towards achieving success. In contrast to self-efficacy, self-release is a process rather than a sustainable phenomenon, and can be expressed both externally and internally through a connection with the value-semantic, motivational spheres of the individual.

scholarly journals Theoretical study of artificial Kerr effect on the self-focusing of laser in a dissipative suspension of silver nanoparticles

2018 ◽  
Vol 25 (8) ◽  
pp. 082310 ◽  
Author(s):  
N. Sepehri Javan ◽  
R. Naderali ◽  
M. Hosseinpour Azad ◽  
M. N. Najafi
Keyword(s):  
Silver Nanoparticles ◽  
Kerr Effect ◽  
Theoretical Study ◽  
The Self ◽  
Self Focusing

Molecular Camouflage: Making Use of Protecting Groups To Control the Self-Assembly of Inorganic Janus Particles onto Metal-Chalcogenide Nanotubes by Pearson Hardness

2011 ◽  
Vol 50 (51) ◽  
pp. 12271-12275 ◽  
Author(s):  
Jugal Kishore Sahoo ◽  
Muhammad Nawaz Tahir ◽  
Faegheh Hoshyargar ◽  
Bahar Nakhjavan ◽  
Robert Branscheid ◽  
...  
Keyword(s):  
Self Assembly ◽  
The Self ◽  
Protecting Groups ◽  
Janus Particles ◽  
Metal Chalcogenide

Theoretical Study on the Mechanism and Kinetics for the Self-Reaction of C2H5O2 Radicals

2012 ◽  
Vol 116 (18) ◽  
pp. 4610-4620 ◽  
Author(s):  
Pei Zhang ◽  
Wenliang Wang ◽  
Tianlei Zhang ◽  
Long Chen ◽  
Yongmei Du ◽  
...  
Keyword(s):  
Theoretical Study ◽  
The Self ◽  
Mechanism And Kinetics

Chiral Expression at the Solid−Liquid Interface: A Joint Experimental and Theoretical Study of the Self-Assembly of Chiral Porphyrins on Graphite

Langmuir ◽  
2008 ◽  
Vol 24 (17) ◽  
pp. 9566-9574 ◽  
Author(s):  
Mathieu Linares ◽  
Patrizia Iavicoli ◽  
Krystallia Psychogyiopoulou ◽  
David Beljonne ◽  
Steven De Feyter ◽  
...  
Keyword(s):  
Self Assembly ◽  
Theoretical Study ◽  
Liquid Interface ◽  
The Self ◽  
Solid Liquid Interface ◽  
Solid Liquid

scholarly journals Healing Performance of a Self-Healing Protective Coating According to Damage Width

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 543
Author(s):  
Dong-Min Kim ◽  
Junseo Lee ◽  
Ju-Young Choi ◽  
Seung-Won Jin ◽  
Kyeong-Nam Nam ◽  
...  
Keyword(s):  
Protective Coating ◽  
Coating Thickness ◽  
Chloride Ion ◽  
The Self ◽  
Self Healing ◽  
Chloride Ion Penetration ◽  
Healing Efficiency ◽  
Sem Study ◽  
Capsule Size ◽  
Ion Penetration

Although self-healing protective coatings have been widely studied, systematic research on healing performance of the coating according to damage width has been rare. In addition, there has been rare reports of self-healing of the protective coating having damage width wider than 100 µm. In this study, self-healing performance of a microcapsule type self-healing protective coating on cement mortar was studied for the coating with damage width of 100–300 µm. The effect of capsule-loading (20 wt%, 30 wt% and 40 wt%), capsule size (65-, 102- and 135-µm-mean diameter) and coating thickness (50-, 80- and 100-µm-thick undercoating) on healing efficiency was investigated by water sorptivity test. Accelerated carbonation test, chloride ion penetration test and scanning electron microscope (SEM) study were conducted for the self-healing coating with a 300-µm-wide damage. Healing efficiency of the self-healing coating decreased with increasing damage width. As capsule-loading, capsule size or coating thickness increased, healing efficiency of the self-healing coating increased. Healing efficiency of 76% or higher was achieved using the self-healing coating with a 300-µm-wide scratch. The self-healing coating with a 200-µm-wide crack showed healing efficiency of 70% or higher. The self-healing coating having a 300-µm-wide scratch showed effective protection of the substrate mortar from carbonation and chloride ion penetration, which was supported by SEM study.

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