Construction of IRA-Like Codes with Cycle Optimization-Constraint and Modified Extended Quasi-Cyclic Structure

2011 ◽  
Author(s):  
Jing Lei ◽  
Bin Chen ◽  
Jianhui Wang
Keyword(s):  
Cyclic Structure ◽  
Optimization Constraint

scholarly journals Electronic Structure of n-Cycloparaphenylenes Directly Observed by Photoemission Spectroscopy

2021 ◽  
Author(s):  
Kaname Kanai ◽  
Takuya Inoue ◽  
Takaya Furuichi ◽  
Kaito Shinoda ◽  
Takashi Iwahashi ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Electronic Structures ◽  
Photoemission Spectroscopy ◽  
Cyclic Structure ◽  
Visible Absorption ◽  
X Ray ◽  
Inverse Photoemission

A series of n-cycloparaphenylenes ([n]CPP) were studied by ultraviolet photoemission, inverse photoemission, ultraviolet-visible absorption, and X-ray photoemission spectroscopy to detect their unique electronic structures. [n]CPP has a cyclic structure in...

Cyclic Structure of Adenovirus DNA

Science ◽  
1965 ◽  
Vol 148 (3666) ◽  
pp. 100-102 ◽  
Author(s):  
K. O. Smith
Keyword(s):  
Cyclic Structure

scholarly journals Graph Neural Networks Meet Neural-Symbolic Computing: A Survey and Perspective

2020 ◽  
Author(s):  
Luís C. Lamb ◽  
Artur d’Avila Garcez ◽  
Marco Gori ◽  
Marcelo O.R. Prates ◽  
Pedro H.C. Avelar ◽  
...  
Keyword(s):  
Neural Networks ◽  
Constraint Satisfaction ◽  
State Of The Art ◽  
Relational Reasoning ◽  
Widespread Application ◽  
Symbolic Computing ◽  
Industry Research ◽  
Optimization Constraint ◽  
The Subject ◽  
Graph Neural Networks

Neural-symbolic computing has now become the subject of interest of both academic and industry research laboratories. Graph Neural Networks (GNNs) have been widely used in relational and symbolic domains, with widespread application of GNNs in combinatorial optimization, constraint satisfaction, relational reasoning and other scientific domains. The need for improved explainability, interpretability and trust of AI systems in general demands principled methodologies, as suggested by neural-symbolic computing. In this paper, we review the state-of-the-art on the use of GNNs as a model of neural-symbolic computing. This includes the application of GNNs in several domains as well as their relationship to current developments in neural-symbolic computing.

Kinetics and Mechanism of the Aminolysis of S-Aryl O-Ethyl Dithiocarbonates in Acetonitrile

2004 ◽  
Vol 69 (12) ◽  
pp. 2174-2182 ◽  
Author(s):  
Hyuck Keun Oh ◽  
Ji Young Oh ◽  
Dae Dong Sung ◽  
Ikchoon Lee
Keyword(s):  
Transition State ◽  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Interaction Constant ◽  
Kinetics And Mechanism ◽  
Cyclic Structure ◽  
Concerted Mechanism ◽  
Tetrahedral Intermediate ◽  
Kinetic Isotope ◽  
Hydrogen Bonded

The aminolysis of S-aryl O-ethyl dithiocarbonates with benzylamines are studied in acetonitrile at -25.0 °C. The βX (βnuc) values are in the range 0.67-0.77 with a negative cross-interaction constant, ρXZ = -0.24, which are interpreted to indicate a concerted mechanism. The kinetic isotope effects involving deuterated benzylamine nucleophiles (XC6H4CH2ND2) are large, kH/kD = 1.41-1.97, suggesting that the N-H(D) bond is partially broken in the transition state by forming a hydrogen-bonded four-center cyclic structure. The concerted mechanism is enforced by the strong push provided by the EtO group which enhances the nucleofugalities of both benzylamine and arenethiolate from the putative zwitterionic tetrahedral intermediate.

STUDY OF IRON–CARBON MIXED CLUSTERS FeCn (n=2−5): A POSSIBLE LINEAR-TO-CYCLIC TRANSITION FROM FeC3 TO FeC4

1996 ◽  
Vol 03 (01) ◽  
pp. 423-427 ◽  
Author(s):  
LAI-SHENG WANG
Keyword(s):  
Photoelectron Spectroscopy ◽  
Cluster Size ◽  
Structural Transition ◽  
Carbon Clusters ◽  
Cyclic Structure ◽  
Cyclic Transition ◽  
Pure Carbon ◽  
Cyclic Isomer ◽  
Anion Photoelectron Spectroscopy ◽  
Mixed Clusters

Small Fe/C mixed clusters, [Formula: see text], are studied by anion photoelectron spectroscopy at 3.49-eV photon energy. The spectra of [Formula: see text] and [Formula: see text] show well-resolved features and are consistent with linear-to-linear detachment transitions. The [Formula: see text] spectrum is quite broad, suggesting large geometry change from the anion to the neutral. Since [Formula: see text] is known to be linear, our data suggest that neutral FeC4 may have a cyclic structure. The spectrum of [Formula: see text] exhibits both sharp and broad features, consistent with the existence of both a linear and a cyclic isomer. A linear-to-cyclic structural transition is thus suggested to take place for the neutral FeCn clusters from n=3−4; for n<4 they are linear and for n≥4 they can be both linear and cyclic. This is similar to the linear-to-cyclic transition occurring for pure carbon clusters from n=9−10 (Ref. 10) but at a much smaller cluster size due to the presence of the Fe atom.

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