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A Review on Fullerenes and its Applications in Health Care Sector
Published in Sarika Verma, Raju Khan, Avanish Kumar Srivastava, Advanced Nanocarbon Materials, 2022
M. Sundararajan, L. Athira, R. A. Renjith, M. Prasanna, R. G. Rejith, S. Ramaswamy, Sarika Verma, M. A. Mohammed-Aslam
Fullerene is an allotrope of carbon. These carbon atoms are connected with single and double bonds to form a partially closed loop. Fullerene contains five- to seven-membered fused rings. It is composed of sheets of hexagonal rings which prevent the structure from being planar. The system of fullerene molecules may be ellipsoid, hollow spherical, cylindrical, or any other sizes and shapes. The spherical fullerene is also called Buckminsterfullerene or buckyballs. The molecule was named after the architect Richard Buckminster Fuller, who created the geodesic dome. Buckminsterfullerene has a similar structure to that of a dome. Cylindrical fullerene is called carbon nanotubes or bucky tubes. The empirical formula of buckminsterfullerene is C60, as it contains 60 carbon atoms. It has a truncated icosahedron structure. It contains 20 hexagons and 12 pentagons. Another fullerene (C70), which contains 70 carbon atoms, is also present, and is similar in shape to a rugby ball. It comprises 25 hexagons and 12 pentagons (Qiao et al. 2007). The structures of C60 and C70 are given in Figure 10.1.
A Bragg Curve Spectrometer for a Multi Detector Array
Published in Dan Shapira, Instrumentation For Heavy Ion Nuclear Research, 2020
J.E. Yurkon, G.D. Westfall, J. Van der Plicht, Z.M. Koenig, B.V. Jacak, R. Fox, G.M. Crawley, M.R. Maier, B.E. Hasselquist, D. Horn
The requirement of covering a large fraction of 4π with MWPC’s, BCS’s, and scintillator telescopes constrains the shape of the detectors. The shape chosen is based on a thirty two face truncated icosahedron containing 20 regular hexagonal faces and 12 regular pentagonal faces - a “soccer ball” geometry. An example of this geometrical object is shown in Figure 1 which shows the proposed multi detector array now under construction at NSCL. This array of counters will have sufficient granularity to handle light particle multiplicities up to 50 with reasonable efficiency. The geometry of one subset of counters presented here is a truncated hexagonal pyramid and is shown schematically in Figure 2. We will report here on the performance of the hexagonally shaped Bragg Curve Spectrometer.
Molecular and Carbon Nanoelectronics
Published in Sergey Edward Lyshevski, Nano- and Micro-Electromechanical Systems, 2018
The carbon-based electronic nanodevices, fabricated utilizing nanotechnology, have been considered as one of the most feasible technologies for nano-ICs. We already briefly covered carbon nanotubes. Let us focus our attention on a family of carbon-based electronics that utilizes fullerenes Cxx and their derivatives. We first examine fullerene-centered nanoelectronics. Carbon bonding plays an important role in organic molecules. A carbon atom contains six electrons. The lowest energy level is occupied by two electrons with oppositely pairing electron spins. Four remaining electrons on 2s, 2px, 2py, and 2pz orbitals participate in bonding. These 2s and 2p orbitals are hybridized to form three types of chemical bonds of carbon with other atoms. This spn hybridization leads to (1) diagonal sp1 hybridization with the resulting bond angle of 180°; (2) triagonal sp2 hybridization with the resulting 120° bond angle; and (3) tetrahedral sp3 hybridization with the resulting bond angle of 109°28′. Other bond angles have been found. In particular, the cubane C8H8 was synthesized with bond angles from 108° to 110°. There exists a great variety of complex organic carbon-based molecules. We concentrate our attention on fullerenes and their derivatives. C60 (with 12 pentagon faces) named fullerene after the architect Buckminster Fuller, who designed a geodesic dome with the same fundamental symmetry. This C60 is the roundest and one of the symmetrically largest known molecules. It consists of 60 carbon atoms arranged in a series of interlocking hexagons and pentagons, forming a structure that looks similar to a soccer ball. C60 forms truncated icosahedron (consisting of 12 pentagons and 20 hexagons with hollow spheroid [see Figure 8.17]) and was reported in 1985 by professors Sir Harry Kroto (U.K.), Richard E. Smalley, and Robert F. Curl, Jr. They were jointly awarded the 1996 Nobel Prize in chemistry.
A Novel Augmentative Backward Reward Function with Deep Reinforcement Learning for Autonomous UAV Navigation
Published in Applied Artificial Intelligence, 2022
Manit Chansuparp, Kulsawasd Jitkajornwanich
Truncated icosahedron, an object with the shape of a soccer ball, is a formation of twelve pentagons and twenty hexagons. This ball-shape object has ever been formed physically for many UAVs’ purposes such as protective cage (MAHMUD 2021) and moving sport balls (Nitta et al. 2015); but, in this work, we propose a novel way to use a virtual truncated icosahedron structure for UAV, in which the ball shape is visualized to both simplifying point cloud data and at the same time avoiding collisions. The only perception UAV has in this work is from a simulation of Velodyne VLP-16 LiDAR sensor, as can be seen in Figure 3.1. It comes with a 100-meter sensor range, 360°, 30° horizontal and vertical field of views and generates ~300,000 points/second. If we put this huge PCD straight through to the neural networks, it will be too complex to model. If we do fixed-interval sampling to a moderate number, some necessary data may be lost.