scholarly journals UNCONVENTIONAL AND EXOTIC MAGNETISM IN CARBON-BASED STRUCTURES AND RELATED MATERIALS

2013 ◽  
Vol 27 (11) ◽  
pp. 1330007 ◽  
Author(s):  
A. L. KUZEMSKY

The detailed analysis of the problem of possible magnetic behavior of the carbon-based structures was fulfilled to elucidate and resolve (at least partially) some unclear issues. It was the purpose of the present paper to look more critically into some conjectures which have been made and to the peculiar and contradictory experimental results in this rather indistinct and disputable field. First the basic physics of magnetism was briefly addressed. Then a few basic questions were thoroughly analyzed and critically reconsidered to elucidate the possible relevant mechanism (if any) which may be responsible for observed peculiarities of the "magnetic" behavior in these systems. The arguments supporting the existence of the intrinsic magnetism in carbon-based materials, including pure graphene were analyzed critically. It was concluded that recently published works have shown that the results of the previous studies, where the "ferromagnetism" was detected in pure graphene, were incorrect. Rather, graphene is strongly diamagnetic, similar to graphite. Thus the possible traces of a quasi-magnetic behavior which some authors observed in their samples may be attributed rather to induced magnetism due to the impurities, defects, etc. On the basis of the present analysis the conclusion was made that the thorough and detailed experimental studies of these problems only may shed light on the very complicated problem of the magnetism of carbon-based materials. Lastly the peculiarities of the magnetic behavior of some related materials and the trends for future developments were mentioned.

2022 ◽  
Author(s):  
Anita Devi ◽  
Sumit Yadav ◽  
Arijit De

Abstract Recent theoretical and experimental studies have shed light on how optical trapping dynamics under femtosecond pulsed excitation are fine-tuned by optical and thermal nonlinearities. Here, we present experimental results of nonlinear optical trapping of single and multiple polystyrene beads (of 1 μm diameter). We show how integration and synchronization of bright-filed video microscopy with confocal detection of backscatter provide both spatial and temporal resolution required to capture intricate details of trapping dynamics. Such spatiotemporal detection is promising to have far-reaching applications in exploring controlled optical trapping and manipulations harnessed by optical and thermal nonlinearities.


Author(s):  
Cinzia Arruzza

A Wolf in the City is a study of tyranny and of the tyrant’s soul in Plato’s Republic. It argues that Plato’s critique of tyranny is an intervention in an ancient debate concerning the sources of the crisis of Athenian democracy and the relation between political leaders and the demos in the last decades of the fifth century BCE. The book shows that Plato’s critique of tyranny should not be taken as a veiled critique of the Syracusan tyrannical regime but, rather, as an integral part of his critique of Athenian democracy. The book also offers an in-depth and detailed analysis of all three parts of the tyrant’s soul, and contends that this approach is necessary to both fully appraise the complex psychic dynamics taking place in the description of the tyrannical man and shed light on Plato’s moral psychology and its relation with his political theory.


2015 ◽  
Vol 813-814 ◽  
pp. 106-110
Author(s):  
Dalbir Singh ◽  
C. Ganesan ◽  
A. Rajaraman

Composites are being used in variety of applications ranging from defense and aircraft structures, where usage is profuse, to vehicle structures and even for repair and rehabilitation. Most of these composites are made of different laminates glued together with matrix for binding and now-a-days fibers of different types are embedded in a composite matrix. The characterizations of material properties of composites are mostly experimental with analytical modeling used to simulate the system behavior. But many times, the composites develop damage or distress in the form of cracking while they are in service and this adds a different dimension as one has to evaluate the response with the damage so that its performance during its remaining life is satisfactory. This is the objective of the present study where a hybrid approach using experimental results on damaged specimens and then analytical finite element are used to evaluate response. This will considerably help in remaining life assessment-RLA- for composites with damage so that design effectiveness with damage could be assessed. This investigation has been carried out on a typical composite with carbon fiber reinforcements, manufactured by IPCL Baroda (India) with trade name INDCARF-30. Experimental studies were conducted on undamaged and damaged specimens to simulate normal continuous loading and discontinuous loading-and-unloading states in actual systems. Based on the experimental results, material characterization inputs are taken and analytical studies were carried out using ANSYS to assess the response under linear and nonlinear material behavior to find the stiffness decay. Using stiffness decay RLA was computed and curves are given to bring the influence of type of damage and load at which damage had occurred.


Author(s):  
Junkui Mao ◽  
Wen Guo ◽  
Zhenxiong Liu ◽  
Jun Zeng

Experiments were carried out to investigate the cooling effectiveness of a lamellar double-decker impingement/effusion structure. Infrared radiation (I.R.) thermal camera was used to measure the temperature on the outside surface of the lamellar double-decker. Experimental results were obtained for a wide range of governing parameters (blowing rate M (0.0017∼0.0066), the ratio of the jet impingement distance to the diameter of film hole H/D (0.5∼1.25), the ratio of the distance between the jet hole and film hole to the diameter of the film hole P/D (0, 3, 4), and the material of double-decker (Steel and Copper)). It was observed that the local cooling effectiveness η varies with all these parameters in a complicated way. All the results show that higher cooling effectiveness η is achieved in larger blowing rate cases. A certain range of H/D and P/D can be designed to result in the maximum cooling effectiveness η. And η is less sensitive to the material type compared with those parameters such as H/D, M and P/D.


2020 ◽  
Vol 11 (1) ◽  
pp. 233-249 ◽  
Author(s):  
Mika Koverola ◽  
Marianna Drosinou ◽  
Jussi Palomäki ◽  
Juho Halonen ◽  
Anton Kunnari ◽  
...  

AbstractThe idea of sex with robots seems to fascinate the general public, raising both enthusiasm and revulsion. We ran two experimental studies (Ns = 172 and 260) where we compared people’s reactions to variants of stories about a person visiting a bordello. Our results show that paying for the services of a sex robot is condemned less harshly than paying for the services of a human sex worker, especially if the payer is married. We have for the first time experimentally confirmed that people are somewhat unsure about whether using a sex robot while in a committed monogamous relationship should be considered as infidelity. We also shed light on the psychological factors influencing attitudes toward sex robots, including disgust sensitivity and interest in science fiction. Our results indicate that sex with a robot is indeed genuinely considered as sex, and a sex robot is genuinely seen as a robot; thus, we show that standard research methods on sexuality and robotics are also applicable in research on sex robotics.


1991 ◽  
Vol 23 (7-9) ◽  
pp. 1319-1326 ◽  
Author(s):  
I. E. Gönenç ◽  
D. Orhon ◽  
B. Beler Baykal

Two basic phenomena, reactor hydraulics and mass transport through biofilm coupled with kinetic expressions for substrate transformations were accounted for in order to describe the soluble COD removal mechanism in anaerobic fixed bed reactors. To provide necessary verification, experimental results from the long term operation of the pilot scale anaerobic reactor treating molasses wastewater were used. Theoretical evaluations verified by these experimental studies showed that a bulk zero-order removal rate expression modified by diffusional resistance leading to bulk half-order and first-order rates together with the particular hydraulic conditions could adequately define the overall soluble COD removal mechanism in an anaerobic fixed bed reactor. The experimental results were also used to determine the kinetic constants for practical application. In view of the complexity of the phenomena involved it is found remarkable that a simple simulation model based on biofilm kinetics is a powerful tool for design and operation of anaerobic fixed bed reactors.


2013 ◽  
Vol 634-638 ◽  
pp. 382-385
Author(s):  
Ke Guo Liu ◽  
Li Li Gu ◽  
Hui Guang Hu ◽  
Rong Yang ◽  
Jun Tao

The experimental studies for purification of 1,8-cineole by vacuum batch distillation as well as the application of additives in 1,8-cineole purification were carried out. There were two steps during the purification. In the first step, experimental results showed that the optimal operation conditions for purification of 1,8-cineole were the temperature of the reboiler at about 320.15 K under a certain vacuum degree. In the second step, the optimal operation temperature of the reboiler was 331.15 K. The optimal reflux ratio was generated finally. Vacuum degree was controlled between 1.1 kPa and 1.3 kPa.


Complexity ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
B. J. Maundy ◽  
A. S. Elwakil ◽  
C. Psychalinos

Two novel nonlinear circuits that exhibit an all-positive pinched hysteresis loop are proposed. These circuits employ two NMOS transistors, one of which operates in its triode region, in addition to two first-order filter sections. We show the equivalency to a charge-controlled resistance (memristance) in a decremental state via detailed analysis. Simulation and experimental results verify the proposed theory.


2014 ◽  
Vol 12 (25) ◽  
pp. 4503-4510 ◽  
Author(s):  
David Roca-López ◽  
Eugenia Marqués-López ◽  
Ana Alcaine ◽  
Pedro Merino ◽  
Raquel P. Herrera

Computational calculations based on experimental results shed light on the mechanistic proposal for a Friedel–Crafts alkylation reaction between indole and nitroalkenes, catalysed by a chiral aminoindanol-derived thiourea.


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