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'''Strip Algebra''' is a set of elements and operators for the description of [[carbon nanotube]] structures, considered as a subgroup of [[polyhedra]], and more precisely, of polyhedra with [[vertex (geometry)|vertices]] formed by three edges. This restriction is imposed on the polyhedra because carbon nanotubes are formed of [[sp2 bond|sp2]] carbon atoms. Strip Algebra was developed initially | |||
<ref>{{cite journal | last = Melchor | first = S. | coauthors = Khokhriakov, N.V.; Savinskii, S.S.| year = 1999 | title = Geometry of Multi-Tube Carbon Clusters and Electronic Transmission in Nanotube Contacts | | |||
journal = Molecular Engineering | volume = 8 | issue = 4 | pages = 315–344 | | |||
doi = 10.1023/A:1008342925348}}</ref> | |||
for the determination of the structure connecting two arbitrary nanotubes, but has also been extended to the connection of three identical nanotubes | |||
<ref>{{cite journal | last = Melchor | first = S. | coauthors = Martin-Martinez, F.J.; Dobado, J.A.| year = 2011 | title = CoNTub v2.0 - Algorithms for Constructing C3-Symmetric Models of Three-Nanotube Junctions. | | |||
journal = J. Chem. Inf. Model. | volume = 51 | pages = 1492–1505 | | |||
doi = 10.1021/ci200056p}}</ref> | |||
==Background== | |||
Graphitic systems are [[molecule]]s and [[crystal]]s formed of [[carbon]] atoms in sp2 hybridization. Thus, the atoms are arranged on a [[hexagon]]al grid. [[Graphite]], nanotubes, and [[fullerene]]s are examples of graphitic systems. All of them share the property that cach atom is bonded to three others (3-[[valence (chemistry)|valent]]). | |||
The relation between the number of vertices, edges and faces of any finite polyhedron is given by [[Euler characteristic|Euler's polyhedron formula]]: | |||
:<math> | |||
e - f - v = 2 (g -1),\, | |||
</math> | |||
where ''e'', ''f'' and ''v'' are the number of edges, faces and vertices, respectively, and ''g'' is the [[genus (mathematics)#Topology|genus]] of the polyhedron, i.e., the number of "holes" in the surface. For example, a [[sphere]] is a surface of genus 0, while a [[torus]] is of genus 1. | |||
==Nomenclature== | |||
A substrip is identified by a pair of natural numbers measuring the position of the last ring in parentheses, together with the turns induced by the defect ring. The number of [[edge (geometry)|edge]]s of the defect can be extracted from these. | |||
:<math>(n,m) [T_+,T_-]</math> | |||
==Elements== | |||
A Strip is defined as a set of consecutive rings, that is able to be joined with others, by sharing a side of the first or last ring. | |||
Numerous complex structures can be formed with strips. As said before, strips have both at the beginning and at the end two connections. With strips only, can be formed two of them. | |||
==Operators== | |||
Given the definition of a strip, a set of operations may be defined. These are necessary to find out the combined result of a set of contiguous strips. | |||
* Addition of two strips: ''(upcoming)'' | |||
* Turn Operators: ''(upcoming)'' | |||
* Inversion of a strip: ''(upcoming)'' | |||
==Applications== | |||
* Strip Algebra has been applied to the construction of [[carbon nanotube | nanotube]] heterojunctions, and was first implemented in the [[CoNTub|CoNTub v1.0]] software, which makes it possible to find the precise position of all the carbon rings needed to produce a heterojunction with arbitrary indices and chirality from two [[Carbon nanotube|nanotube]]s. | |||
== References == | |||
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[[Category:Carbon nanotubes]] |
Revision as of 12:02, 1 January 2014
Strip Algebra is a set of elements and operators for the description of carbon nanotube structures, considered as a subgroup of polyhedra, and more precisely, of polyhedra with vertices formed by three edges. This restriction is imposed on the polyhedra because carbon nanotubes are formed of sp2 carbon atoms. Strip Algebra was developed initially [1] for the determination of the structure connecting two arbitrary nanotubes, but has also been extended to the connection of three identical nanotubes [2]
Background
Graphitic systems are molecules and crystals formed of carbon atoms in sp2 hybridization. Thus, the atoms are arranged on a hexagonal grid. Graphite, nanotubes, and fullerenes are examples of graphitic systems. All of them share the property that cach atom is bonded to three others (3-valent).
The relation between the number of vertices, edges and faces of any finite polyhedron is given by Euler's polyhedron formula:
where e, f and v are the number of edges, faces and vertices, respectively, and g is the genus of the polyhedron, i.e., the number of "holes" in the surface. For example, a sphere is a surface of genus 0, while a torus is of genus 1.
Nomenclature
A substrip is identified by a pair of natural numbers measuring the position of the last ring in parentheses, together with the turns induced by the defect ring. The number of edges of the defect can be extracted from these.
Elements
A Strip is defined as a set of consecutive rings, that is able to be joined with others, by sharing a side of the first or last ring.
Numerous complex structures can be formed with strips. As said before, strips have both at the beginning and at the end two connections. With strips only, can be formed two of them.
Operators
Given the definition of a strip, a set of operations may be defined. These are necessary to find out the combined result of a set of contiguous strips.
- Addition of two strips: (upcoming)
- Turn Operators: (upcoming)
- Inversion of a strip: (upcoming)
Applications
- Strip Algebra has been applied to the construction of nanotube heterojunctions, and was first implemented in the CoNTub v1.0 software, which makes it possible to find the precise position of all the carbon rings needed to produce a heterojunction with arbitrary indices and chirality from two nanotubes.
References
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The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more
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In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang
Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules
Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.
A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running
The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more
There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang