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Introduction to Carbon Nanotube 2D Layer Assisted by Surface Plasmon Resonance Based Sensor
Published in Sanjeev Kumar Raghuwanshi, Santosh Kumar, Yadvendra Singh, 2D Materials for Surface Plasmon Resonance-based Sensors, 2021
Sanjeev Kumar Raghuwanshi, Santosh Kumar, Yadvendra Singh
CNTs belong to the fullerene nanostructure family (Aqel, Abou El-Nour, Ammar, and Al-Warthan 2012). Fullerenes are a category of allotropes of carbon, shown in Fig. 6.1, mostly made of carbon molecules, are a hollow-shaped sphere, tube-shaped, or an ellipsoidal. CNTs, also known as buckytubes, are cylindrical fullerenes. Fullerenes have a graphite-like composition, consisting of a layer of hexagonal connected rings, except that they conceive of pentagonal (or heptagonal) rings that prevent planarization. A single-layer graphene sheet, as shown in Fig. 6.2, can be rolled in several directions to produce various forms of CNTs. Because of its symmetric composition, a normal CNT does have a hexagonal array of carbon atoms in a tube shape and has extraordinary properties. Their activity depends solely on the helix’s nature, and therefore they behave as a metal or as a semiconductor.
The Journey of Nanotechnology in Product Development
Published in Cherry Bhargava, Amit Sachdeva, Pardeep Kumar Sharma, Smart Nanotechnology with Applications, 2020
Divya Thakur, Sheetu Wadhwa, Sachin Kumar Singh, Rajesh Kumar, Rohit Vij
Some non-vesicular carriers such as nanoparticles (polymeric and lipidic) are nano-size range drug delivery systems, widely utilized owing to their advantages over other systems. Solid lipid nanoparticles are another widely used and popular colloidal system which is composed of liquid lipid and solid lipid and has potential to deliver pharmaceuticals, cosmetics, and neutraceuticals. Metallic nanoparticles are developed using gold, silver, platinum, nickel, iron, or their oxides for the delivery of drugs. Carbon nanotubes (CNTs) are made up of carbon in the order of nanometer in size, fabricated as single or multiwalled, and exhibit extensive tensile strength [16]. Quantum dots are another man-made nano-scale structures which have unique optical and electrical properties. Fullerenes are carbon allotropes, composed of carbon atoms which are connected through single and double bond linkage, and form hollow mesh-like structures [17]. Nanoemulsion systems are a mixture of two immiscible liquids, in which one liquid is the dispersed phase which is dispersed into another phase known as the continuous phase [18]. Majority of nanotechnology-based commercialized products such as liposomes, polymeric nanoparticles, micelles, etc. are developed for different types of cancer, incorporating different anti-cancer drugs which generally possess toxicity issues and other side effects (shown in Table 1.1), and some nanotechnology-based marketed cosmeceutical products are discussed in Table 1.2 [15,19]).
Materials Used for General Radiation Detection
Published in Alan Owens, Semiconductor Radiation Detectors, 2019
Silicon is a group IVA material that crystallizes in a diamond cubic crystal lattice structure at a temperature of 1414 °C. It has a low density of 2.39 gcm–3 and a relatively small indirect bandgap of 1.12 eV. Whilst it has modest electron and hole mobilities (i.e., 1500 cm2V–1s–1 and 480 cm2V–1s–1, respectively), its mu-tau products are extremely high (µeτe~ µhτh ≥ 1 cm2V–1). Two allotropes of silicon exist at room temperature: amorphous and crystalline. Amorphous Si is widely used in the production of thin-film solar cells, while crystalline Si is used extensively in the semiconductor industry for the production of electronic components and radiation detectors. More than 75% of all single crystal silicon wafers are grown by the Czochralski (CZ) method. Higher quality material can be produced using the float-zone technique, but at greater expense. For radiation detection applications, the best spectral performances have been achieved using epitaxial materials produced by liquid phase epitaxy (LPE) or vapor phase epitaxy (VPE).
On the effect of local torsion on the electromechanical properties of armchair boron nitride nanoribbons
Published in Molecular Physics, 2022
R. Sadeghi, M. Yaghobi, M. R. Niazian, M. A. Ramzanpour
In recent years, caused by the attractive chemical and physical properties of the fullerene, a spherical allotrope of carbon, several research groups have investigated the properties of fullerene-like structures which are made from other atoms, including the members of the groups III, IV and V of the periodic table [1,2]. These attractive properties have resulted in finding different applications for these fullerene-like structures [3]. Similarly, physical and chemical properties of two-dimensional (2D) graphene-like nanostructures have also been considered for investigation [4]. Boron nitride (BN) is an inorganic compound with equal numbers of boron and nitrogen atoms which is isoelectronic to a similarly structured carbon lattice and exists in various crystalline forms. Among the BN polymorphs, the hexagonal form which is similar to the graphite is the softest and most stable structure [5].
Spectroscopy of astrophysically relevant ions in traps
Published in Molecular Physics, 2020
In the 1985 experiment, radiation from the second harmonic of an Nd:YAG laser was used to produce carbon clusters from a rotating graphite disk. The neutral molecules were ionised in a helium expansion and detected via time-of-flight mass spectrometry. The results showed a distribution where, for mass-to-charge ratios (m/z) of greater than 480, only species containing an even number of carbon atoms were observed. Moreover, a slightly enhanced peak at , and also one at , was seen. These ‘clusters’ are now known as fullerenes, an allotrope of carbon in addition to the previously identified graphite and diamond. It was immediately recognised that this may have implications for the DIB enigma and, in 1987, Kroto highlighted the astrophysical importance of the singly charged cation C, writing ‘The present observations indicate that C might survive in the general interstellar medium (probably as the ion C) protected by its unique ability to survive processes so drastic that, most if not all, other known molecules are destroyed’ [68]. This conjecture was subsequently shown to be correct.
Fluoride removal from water using alumina and aluminum-based composites: A comprehensive review of progress
Published in Critical Reviews in Environmental Science and Technology, 2021
Sikpaam Issaka Alhassan, Lei Huang, Yingjie He, Lvji Yan, Bichao Wu, Haiying Wang
Carbon is one of the materials that have been widely researched for its defluorination potential because it is easily accessible and relatively cheaper. Carbon has three allotropes (Allotropy or allotropism is simply the ability of some chemical elements to exist in two or more different forms, in the same physical state). Diamond, graphite and Fullerene are the three allotropes of carbon. Diamond is not good for fluoride adsorption but graphite and fullerene have been reported as good adsorbents for fluoride adsorption (Mohapatra et al., 2009). Jin et al (2015) studied alumina modified expanded graphite (Al2O3/E-G) composite using facile solution method at 45 °C as a medium for 2 h for the removal of fluoride ions from drinking water. Maximum fluoride removal of 94.4% at an adsorption capacity of 1.18 mg·g−1 was observed by (Al2O3/E-G) at a pH range of 3–7. The study further noted that such a high adsorption rate was possible because fluoride adsorption was not affected by the pH of the aqueous solution. As such, the adsorbent was more effective for removing lower concentrations of fluoride ions beyond permissible levels. Abe et al. (2004) compared the fluoride adsorption capacities of different carbon adsorbents. The authors concluded on the adsorption capacities of the various carbon adsorbents on the following order; bone char > Coal charcoal > wood charcoal > Carbon black > Petroleum cake. Moreover, Gupta et al. (2007) investigated the fluoride removal potential of waste carbon slurries generated from fuel-oil generators. The solid from the slurry was calcined at a temperature of 45 °C, washed in Sodium hydroxide solution and finally purified by washing in fluoride-free water. The product was heated at 100 °C and further separated into the various components. The composition was as follows (Carbon 92.0%, Al 0.45%, Fe 0.6%). The optimum adsorption occurred at pH 7.6 and it removed fluoride down beyond WHO recommended level of ˂1.5 mg·L−1.