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Abdulsattar M.A.,Ministry of Science and Technology
Beilstein Journal of Nanotechnology | Year: 2013

Infrared spectra of hydrogenated diamond nanocrystals of one nanometer length are calculated by ab initio methods. Positions of atoms are optimized via density functional theory at the level of the generalized gradient approximation of Perdew, Burke and Ernzerhof (PBE) using 3-21G basis states. The frequencies in the vibrational spectrum are analyzed against reduced masses, force constants and intensities of vibration. The spectrum can be divided into two regions depending on the properties of the vibrations or the gap separating them. In the first region, results show good matching to several experimentally obtained lines. The 500 cm-1 broad-peak acoustical branch region is characterized by pure C-C vibrations. The optical branch is centered at 1185 cm-1. Calculations show that several C-C vibrations are mixed with some C-H vibrations in the first region. In the second region the matching also extends to C-H vibration frequencies that include different modes such as symmetric, asymmetric, wagging, scissor, rocking and twisting modes. In order to complete the picture of the size dependence of the vibrational spectra, we analyzed the spectra of ethane and adamantane. The present analysis shows that acoustical and optical branches in diamond nanocrystals approach each other and collapse at 963 cm-1 in ethane. Variation of the highest reduced-mass-mode C-C vibrations from 1332 cm-1 of bulk diamond to 963 cm-1 for ethane (red shift) is shown. The analysis also shows the variation of the radial breathing mode from 0 cm-1 of bulk diamond to 963 cm-1 for ethane (blue shift). These variations compare well with experiment. Experimentally, the above-mentioned modes appear shifted from their exact positions due to overlap with neighboring modes. © 2013 Abdulsattar; licensee Beilstein-Institut. Source


Abdulsattar M.A.,Ministry of Science and Technology
Solid State Sciences | Year: 2011

In order to reduce computational efforts, and separate surface and core properties, diamond nanocrystals in the present model is represented by a heterojunction between the surface and the core in which the surface represents the outer most four layers and the core by the rest of the internal region of nanocrystal. Ab initio restricted Hartree-Fock (RHF) method coupled with the large unit cell method (LUC) is used to determine the electronic structure and physical properties of diamond nanocrystals core part with different sizes. The use of STO-3G basis choice is made to be able to compare to semiempirical methods using the complete neglect of differential overlap (CNDO) that uses Slater type orbitals (STO). The oxygenated (001)-(1 × 1) facet that expands with larger sizes of nanocrystals is also investigated to determine the rule of the surface in nanocrystals electronic structure. The results show that the present method agrees with semiempirical method contraction of lattice constant with increasing nanocrystal size but disagrees with energy gap variation with nanocrystal size in some regions. After nearly 1.4 nm the energy gap which is controlled by surface states begins to rise. The lowest unoccupied molecular orbital (LUMO) is attributed to surface states that largely reduce the value of energy gap. The sources of disagreement between semiempirical and ab initio results are discussed. The present method shows a maximum increment of the lattice constant by 3.3% over the calculated bulk for the smallest diamond nanocrystals. The surface states are found mostly non-degenerated because of the effect of surface discontinuity and oxygen atoms. Valance and conduction bands are wider on the surface due to splitting and oxygen atoms. The method also shows fluctuations in the converged energy gap, valence band width and cohesive energy of the core part of nanocrystal. These fluctuations might partially explain the controversial experimental results for diamond nanocrystals greater than 1.4 nm in size. The method of the present model has threefold results; it can be used to obtain the electronic structure of bulk, surface, and nanocrystals. © 2011 Elsevier Masson SAS. All rights reserved. Source


Grant
Agency: GTR | Branch: EPSRC | Program: | Phase: Research Grant | Award Amount: 3.44M | Year: 2013

Compared to many parts of the world, the UK has under-invested in its infrastructure in recent decades. It now faces many challenges in upgrading its infrastructure so that it is appropriate for the social, economic and environmental challenges it will face in the remainder of the 21st century. A key challenge involves taking into account the ways in which infrastructure systems in one sector increasingly rely on other infrastructure systems in other sectors in order to operate. These interdependencies mean failures in one system can cause follow-on failures in other systems. For example, failures in the water system might knock out electricity supplies, which disrupt communications, and therefore transportation, which prevent engineers getting to the original problem in the water infrastructure. These problems now generate major economic and social costs. Unfortunately they are difficult to manage because the UK infrastructure system has historically been built, and is currently operated and managed, around individual infrastructure sectors. Because many privatised utilities have focused on operating infrastructure assets, they have limited experience in producing new ones or of understanding these interdependencies. Many of the old national R&D laboratories have been shut down and there is a lack of capability in the UK to procure and deliver the modern infrastructure the UK requires. On the one hand, this makes innovation risky. On the other hand, it creates significant commercial opportunities for firms that can improve their understanding of infrastructure interdependencies and speed up how they develop and test their new business models. This learning is difficult because infrastructure innovation is undertaken in complex networks of firms, rather than in an individual firm, and typically has to address a wide range of stakeholders, regulators, customers, users and suppliers. Currently, the UK lacks a shared learning environment where these different actors can come together and explore the strengths and weaknesses of different options. This makes innovation more difficult and costly, as firms are forced to learn by doing and find it difficult to anticipate technical, economic, legal and societal constraints on their activity before they embark on costly development projects. The Centre will create a shared, facilitated learning environment in which social scientists, engineers, industrialists, policy makers and other stakeholders can research and learn together to understand how better to exploit the technical and market opportunities that emerge from the increased interdependence of infrastructure systems. The Centre will focus on the development and implementation of innovative business models and aims to support UK firms wishing to exploit them in international markets. The Centre will undertake a wide range of research activities on infrastructure interdependencies with users, which will allow problems to be discovered and addressed earlier and at lower cost. Because infrastructure innovations alter the social distribution of risks and rewards, the public needs to be involved in decision making to ensure business models and forms of regulation are socially robust. As a consequence, the Centre has a major focus on using its research to catalyse a broader national debate about the future of the UKs infrastructure, and how it might contribute towards a more sustainable, economically vibrant, and fair society. Beneficiaries from the Centres activities include existing utility businesses, entrepreneurs wishing to enter the infrastructure sector, regulators, government and, perhaps most importantly, our communities who will benefit from more efficient and less vulnerable infrastructure based services.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: INCO.2013-3.1 | Award Amount: 2.93M | Year: 2013

INNO INDIGO will set up a more relevant STI approach in terms of social and technical innovation, a broader in terms of funding and a more focussed in terms of topics - to answer the needs of the European as well as Indian societies and markets and address the needs of the engines for innovation. These are SMEs and industries as well as existing clusters of excellence. Future joint programmes will be directed towards the interaction of academia and industry a critical interface for effective innovation. It is also very important to use the STI experience of regions successful funding clusters of excellence for joint calls. On a larger scale INNO INDIGO aims at contributing to ensure global competitiveness and to satisfy social needs through innovation. Another important task of INNO INDIGO will be to optimize the outreach of the project and facilitate the networking of funding organizations in Europe and India in order to discuss, prepare and implement joint calls on a regular basis. Therefore an open platform for funders will be implemented. A number of national funding agencies has been involved in the joint calls of the ongoing ERA-Net. This was important to gain experiences, approve and adjust tools and methods in existing strategies for the call management. Within the INNO INDIGO process of the future joint calls the strategies for an enhanced management structure will steadily analysed and optimized also in order to develop common governance principles. Further funding organizations in both Europe and India will be informed about the ongoing collaboration in order to raise their interest in a participation and therefore to enlarge the outreach of the project. In Europe this implies especially Member States as well as Associated Countries that do not have bilateral research programmes with India and would also benefit from the Innovation approach of INNO INDIGO. Furthermore scenarios for cooperation beyond the lifetime of INNO INDIGO will be developed.


Grant
Agency: Cordis | Branch: H2020 | Program: ERA-NET-Cofund | Phase: NMP-14-2015 | Award Amount: 49.69M | Year: 2016

M-ERA.NET 2 aims at coordinating the research efforts of the participating EU Member States, Associated States and Regions as well as of selected global partners in materials research and innovation, including materials for low carbon energy technologies and related production technologies. A large network of 43 national and regional funding organisations from 23 EU Members States and Associated States and 5 countries outside Europe will implement joint calls to fund excellent innovative transnational RTD cooperation, including one call for proposals with EU co-funding and additional non-cofunded calls. Continuing the activities started under the predecessor project M-ERA.NET (2/2012-1/2016), the M-ERA.NET 2 consortium will support relevant thematic areas, such as -for example- surfaces, coatings, composites, additive manufacturing or computational materials engineering. Research on materials enabling low carbon energy technologies will be particularly highlighted as a main target of the cofunded call (Call 2016) with a view to implementing relevant parts of the Materials Roadmap Enabling Low Carbon Energy Technologies (SEC(2011)1609), and relevant objectives of the SET-Plan (COM (2009)519). The appropriate scope of the cofunded call and the additional joint calls will be defined in cooperation with relevant stakeholders including national and regional RTD communities, the EC and the EMIRI (Energy Materials Industrial Research Initiative) as well as an external Strategic Experts Group. M-ERA.NET 2 will support the whole innovation chain, clarifying for each topic the appropriate Technology Readiness Levels (TRLs) to be addressed through the transnational RTD projects. The consortium will be aware of the TRLs which are covered by the EC through Horizon 2020 topics as well as by other schemes. Gaps will be identified and M-ERA.NET 2 will aim at offering a complementary support scheme.

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