Role of nanoparticles in achieving macroscale superlubricity of graphene/nano-SiO2 particle composites

AbstractRecent studies have reported that adding nanoparticles to graphene enables macroscale superlubricity to be achieved. This study focuses on the role of nanoparticles in achieving superlubricity. First, because graphene nanoscrolls can be formed with nanoparticles as seeds under shear force, the applied load (or shear force) is adjusted to manipulate the formation of graphene nanoscrolls and to reveal the relationship between graphene-nanoscroll formation and superlubricating performance. Second, the load-carrying role of spherical nano-SiO2 particles during the friction process is verified by comparison with an elaborately designed fullerene that possesses a hollow-structured graphene nanoscroll. Results indicate that the incorporated nano-SiO2 particles have two roles in promoting the formation of graphene nanoscrolls and exhibiting load-carrying capacity to support macroscale forces for achieving macroscale superlubricity. Finally, macroscale superlubricity (friction coefficient: 0.006–0.008) can be achieved under a properly tuned applied load (2.0 N) using a simple material system in which a graphene/nano-SiO2 particle composite coating slides against a steel counterpart ball without a decorated diamond-like carbon film. The approach described in this study could be of significance in engineering.

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Mechanical Stresses Induced by Compression in Castings of the Load-carrying Grate

Archives of Foundry Engineering ◽

10.1515/afe-2016-0025 ◽

2016 ◽

Vol 16 (2) ◽

pp. 51-54

Author(s):

J. Słowik ◽

A. Drotlew ◽

B. Piekarski

Keyword(s):

Heat Treatment ◽

Stress Distribution ◽

Stress Level ◽

Stress Transfer ◽

State Of Stress ◽

Structure Changes ◽

Load Carrying ◽

The Relationship ◽

Forced Movement

Abstract The main aim of this study was to examine the compression-induced state of stress arising in castings of the guide grates during operation in pusher-type furnaces for heat treatment. The effect of grate compression is caused by its forced movement in the furnace. The introduction of flexible segments to the grate structure changes in a significant way the stress distribution, mainly by decreasing its value, and consequently considerably extends the lifetime of the grates. The stress distribution was examined in the grates with flexible segments arranged crosswise (normal to the direction of the grate compression) and lengthwise (following the direction of force). A regression equation was derived to describe the relationship between the stress level in a row of ribs in the grate and the number of flexible segments of a lengthwise orientation placed in this row. It was found that, regardless of the distribution of the flexible segments in a row, the stress values were similar in all the ribs included in this row, and in a given row of the ribs/flexible segments a similar state of stress prevailed, irrespective of the position of this row in the whole structure of the grate and of the number of the ribs/flexible segments introduced therein. Parts of the grate responsible for the stress transfer were indicated and also parts which play the role of an element bonding the structure.

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Choosing a Markov blanket

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002632 ◽

2020 ◽

Vol 43 ◽

Author(s):

Thomas Parr

Keyword(s):

Markov Blanket ◽

Target Article ◽

The Relationship

Abstract This commentary focuses upon the relationship between two themes in the target article: the ways in which a Markov blanket may be defined and the role of precision and salience in mediating the interactions between what is internal and external to a system. These each rest upon the different perspectives we might take while “choosing” a Markov blanket.

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Staring Down Death

Crisis ◽

10.1027/0227-5910/a000367 ◽

2016 ◽

Vol 37 (3) ◽

pp. 212-217 ◽

Cited By ~ 7

Author(s):

Thomas E. Joiner ◽

Melanie A. Hom ◽

Megan L. Rogers ◽

Carol Chu ◽

Ian H. Stanley ◽

...

Keyword(s):

Suicide Risk ◽

Clinical Utility ◽

Blink Rate ◽

Specific Task ◽

Careful Planning ◽

Eye Blink ◽

Eye Blinks ◽

Potential Clinical Utility ◽

The Relationship

Abstract. Background: Lowered eye blink rate may be a clinically useful indicator of acute, imminent, and severe suicide risk. Diminished eye blink rates are often seen among individuals engaged in heightened concentration on a specific task that requires careful planning and attention. Indeed, overcoming one’s biological instinct for survival through suicide necessitates premeditation and concentration; thus, a diminished eye blink rate may signal imminent suicidality. Aims: This article aims to spur research and clinical inquiry into the role of eye blinks as an indicator of acute suicide risk. Method: Literature relevant to the potential connection between eye blink rate and suicidality was reviewed and synthesized. Results: Anecdotal, cognitive, neurological, and conceptual support for the relationship between decreased blink rate and suicide risk is outlined. Conclusion: Given that eye blinks are a highly observable behavior, the potential clinical utility of using eye blink rate as a marker of suicide risk is immense. Research is warranted to explore the association between eye blink rate and acute suicide risk.

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Parenting Behaviors and Anxiety in Young Adults

Journal of Individual Differences ◽

10.1027/1614-0001/a000169 ◽

2015 ◽

Vol 36 (3) ◽

pp. 170-176 ◽

Cited By ~ 5

Author(s):

Erin N. Stevens ◽

Joseph R. Bardeen ◽

Kyle W. Murdock

Keyword(s):

Effortful Control ◽

Parenting Behaviors ◽

Protective Role ◽

Anxiety Symptoms ◽

Interactive Effects ◽

Parental Overprotection ◽

High Control ◽

Development Of Anxiety ◽

The Relationship

Parenting behaviors – specifically behaviors characterized by high control, intrusiveness, rejection, and overprotection – and effortful control have each been implicated in the development of anxiety pathology. However, little research has examined the protective role of effortful control in the relation between parenting and anxiety symptoms, specifically among adults. Thus, we sought to explore the unique and interactive effects of parenting and effortful control on anxiety among adults (N = 162). Results suggest that effortful control uniquely contributes to anxiety symptoms above and beyond that of any parenting behavior. Furthermore, effortful control acted as a moderator of the relationship between parental overprotection and anxiety, such that overprotection is associated with anxiety only in individuals with lower levels of effortful control. Implications for potential prevention and intervention efforts which specifically target effortful control are discussed. These findings underscore the importance of considering individual differences in self-regulatory abilities when examining associations between putative early-life risk factors, such as parenting, and anxiety symptoms.

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Social Support, Emotional Intelligence, and Posttraumatic Stress Disorder Symptoms

Journal of Individual Differences ◽

10.1027/1614-0001/a000185 ◽

2016 ◽

Vol 37 (1) ◽

pp. 31-39 ◽

Cited By ~ 8

Author(s):

Nicole L. Hofman ◽

Austin M. Hahn ◽

Christine K. Tirabassi ◽

Raluca M. Gaher

Keyword(s):

Social Support ◽

Posttraumatic Stress Disorder ◽

Emotional Intelligence ◽

Protective Factors ◽

Posttraumatic Stress ◽

Stress Disorder ◽

Traumatic Events ◽

Ptsd Symptoms ◽

The Relationship

Abstract. Exposure to traumatic events and the associated risk of developing Posttraumatic stress disorder (PTSD) symptoms is a significant and overlooked concern in the college population. It is important for current research to identify potential protective factors associated with the development and maintenance of PTSD symptoms unique to this population. Emotional intelligence and perceived social support are two identified protective factors that influence the association between exposure to traumatic events and PTSD symptomology. The current study examined the mediating role of social support in the relationship between emotional intelligence and PTSD symptoms. Participants included 443 trauma-exposed university students who completed online questionnaires. The results of this study indicated that social support mediates the relationship between emotional intelligence and reported PTSD symptoms. Thus, emotional intelligence is significantly associated with PTSD symptoms and social support may play an integral role in the relationship between emotional intelligence and PTSD. The current study is the first to investigate the role of social support in the relationship between emotional intelligence and PTSD symptoms. These findings have important treatment and prevention implications with regard to PTSD.

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Coping Humor as a Mediator Between Emotional Intelligence and Job Satisfaction

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000185 ◽

2017 ◽

Vol 16 (3) ◽

pp. 155-159 ◽

Cited By ~ 4

Author(s):

Peizhen Sun ◽

Jennifer J. Chen ◽

Hongyan Jiang

Keyword(s):

Job Satisfaction ◽

Emotional Intelligence ◽

Future Research ◽

Satisfaction Scale ◽

Primary School Teachers ◽

Mediating Role ◽

Regulation Of Emotion ◽

The Relationship ◽

Overall Job Satisfaction

Abstract. This study investigated the mediating role of coping humor in the relationship between emotional intelligence (EI) and job satisfaction. Participants were 398 primary school teachers in China, who completed the Wong Law Emotional Intelligence Scale, Coping Humor Scale, and Overall Job Satisfaction Scale. Results showed that coping humor was a significant mediator between EI and job satisfaction. A further examination revealed, however, that coping humor only mediated two sub-dimensions of EI (use of emotion and regulation of emotion) and job satisfaction. Implications for future research and limitations of the study are discussed.

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