Tunnelling in Molecules

Tunnelling in Molecules PDF Author: Johannes Kästner
Publisher: Royal Society of Chemistry
ISBN: 1839160381
Category : Science
Languages : en
Pages : 453

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Book Description
Quantum tunnelling is one of the strangest phenomena in chemistry, where we see the wave nature of atoms acting in “impossible” ways. By letting molecules pass through the kinetic barrier instead of over it, this effect can lead to chemical reactions even close to the absolute zero, to atypical spectroscopic observations, to bizarre selectivity, or to colossal isotopic effects. Quantum mechanical tunnelling observations might be infrequent in chemistry, but it permeates through all its disciplines producing remarkable chemical outcomes. For that reason, the 21st century has seen a great increase in theoretical and experimental findings involving molecular tunnelling effects, as well as in novel techniques that permit their accurate predictions and analysis. Including experimental, computational and theoretical chapters, from the physical and organic to the biochemistry fields, from the applied to the academic arenas, this new book provides a broad and conceptual perspective on tunnelling reactions and how to study them. Quantum Tunnelling in Molecules is the obligatory stop for both the specialist and those new to this world.

Tunnelling in Molecules

Tunnelling in Molecules PDF Author: Johannes Kästner
Publisher: Royal Society of Chemistry
ISBN: 1839160381
Category : Science
Languages : en
Pages : 453

Get Book

Book Description
Quantum tunnelling is one of the strangest phenomena in chemistry, where we see the wave nature of atoms acting in “impossible” ways. By letting molecules pass through the kinetic barrier instead of over it, this effect can lead to chemical reactions even close to the absolute zero, to atypical spectroscopic observations, to bizarre selectivity, or to colossal isotopic effects. Quantum mechanical tunnelling observations might be infrequent in chemistry, but it permeates through all its disciplines producing remarkable chemical outcomes. For that reason, the 21st century has seen a great increase in theoretical and experimental findings involving molecular tunnelling effects, as well as in novel techniques that permit their accurate predictions and analysis. Including experimental, computational and theoretical chapters, from the physical and organic to the biochemistry fields, from the applied to the academic arenas, this new book provides a broad and conceptual perspective on tunnelling reactions and how to study them. Quantum Tunnelling in Molecules is the obligatory stop for both the specialist and those new to this world.

Civil Excavations and Tunnelling

Civil Excavations and Tunnelling PDF Author: Ratan Tatiya
Publisher: Thomas Telford
ISBN: 9780727733405
Category : Technology & Engineering
Languages : en
Pages : 346

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Book Description
This is a comprehensive text on Civil Excavations at the surface as well as subsurface locales, including tunnels that could be created with or without aid of explosives using latest methods, equipment and techniques with due consideration to safety and the environment. Criteria to select equipment have been demonstrated through a case study which gives consideration to factors related to environment, safety, ergonomics, and the economy.

Tunnelling

Tunnelling PDF Author: Alan Muir Wood
Publisher: CRC Press
ISBN: 0203477669
Category : Architecture
Languages : en
Pages : 320

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Book Description
Tunnelling has become a fragmented process, excessively influenced by lawyers'notions of confrontational contractual bases. This prevents the pooling of skills, essential to the achievement of the promoters' objectives. Tunnelling: Management by Design seeks the reversal of this trend. After a brief historical treatment of selected developments, th

Quantum Tunnelling in Enzyme-catalysed Reactions

Quantum Tunnelling in Enzyme-catalysed Reactions PDF Author: Rudolf K. Allemann
Publisher: Royal Society of Chemistry
ISBN: 0854041222
Category : Science
Languages : en
Pages : 412

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Book Description
In recent years, there has been an explosion in knowledge and research associated with the field of enzyme catalysis and H-tunneling. Rich in its breath and depth, this introduction to modern theories and methods of study is suitable for experienced researchers those new to the subject. Edited by two leading experts, and bringing together the foremost practitioners in the field, this up-to-date account of a rapidly developing field sits at the interface between biology, chemistry and physics. It covers computational, kinetic and structural analysis of tunnelling and the synergy in combining these methods (with a major focus on H-tunneling reactions in enzyme systems). The book starts with a brief overview of proton and electron transfer history by Nobel Laureate, Rudolph A. Marcus. The reader is then guided through chapters covering almost every aspect of reactions in enzyme catalysis ranging from descriptions of the relevant quantum theory and quantum/classical theoretical methodology to the description of experimental results. The theoretical interpretation of these large systems includes both quantum mechanical and statistical mechanical computations, as well as simple more approximate models. Most of the chapters focus on enzymatic catalysis of hydride, proton and H" transfer, an example of the latter being proton coupled electron transfer. There is also a chapter on electron transfer in proteins. This is timely since the theoretical framework developed fifty years ago for treating electron transfers has now been adapted to H-transfers and electron transfers in proteins. Accessible in style, this book is suitable for a wide audience but will be particularly useful to advanced level undergraduates, postgraduates and early postdoctoral workers.

Tunnelling ’94

Tunnelling ’94 PDF Author: Vidar Aarvold
Publisher: Springer
ISBN: 1461526469
Category : Science
Languages : en
Pages : 808

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Book Description
It is now more than twenty years since a proposal was first mooted to hold an international tunnelling symposium in Britain. At the time of the first symposium, held in London in 1976, the Channel Tunnel pro ject had just been shelved. Last weekend a charity walk was held in the finished tunnel, which will be open for business later in the year. Tunnels have figured prominently, and at times spectacularly, in the development of national and international links and it is hoped that such links gather pace in the future. It is particularly pleasing that Alastair Biggart of Storebrelt has agreed to deliver the twenty-sixth Sir Julius Wernher Memorial Lecture of the Institution of Mining and Metallurgy, entitled 'The changing face of tunnelling', at the start of this event. * Although almost every edition of the technical journals on tunnelling reports another £1 billion scheme somewhere in the world, it would be unfair of me to suggest that tunnelling is restricted to these prestigious schemes for major transport links. Much of the work that makes mod ern life possible receives hardly a mention outside the technical press and one suspects that society at large applies the 'out of sight, out of mind' attitude even more readily to underground construction than it does to other forms of engineering. Clearly, there is a contiiming need to improve the capacity and performance of our infrastructure, while hav ing a careful regard for the environment.

Tunnelling and Negative Resistance Phenomena in Semiconductors

Tunnelling and Negative Resistance Phenomena in Semiconductors PDF Author: D. K. Roy
Publisher: Elsevier
ISBN: 1483278956
Category : Technology & Engineering
Languages : en
Pages : 230

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Book Description
Tunnelling and Negative Resistance Phenomena in Semiconductors presents a critical review of tunneling theory and shows how this leads to the negative resistance phenomena in pn junctions. The physics, technology, and circuitry of semiconductor negative resistance devices are surveyed. The book challenges the conventional assumptions of tunneling theory and proposes an alternative approach that allows the possibility of a change in energy during tunneling. It also introduces the reader to the manufacture, operation, and applications of semiconductor negative resistance devices. Comprised of five chapters, this volume begins by presenting a logical physical interpretation of the wavefunction with its so-called ill-behaved nature and considering other consequences of the energy distribution effect. The next chapter is devoted to the tunneling effect through tunnel diodes along with other properties of this device. The circuitry and technology of tunnel diodes as well as backward and Zener diodes are then examined, along with negative conductance devices that are used as microwave sources. The final chapter is concerned with negative conductance switching devices. This book is intended for students and practitioners in the fields of physics and electronics.

Tunnelling Contracts and Site Investigation

Tunnelling Contracts and Site Investigation PDF Author: Dr P.B. Attewell
Publisher: CRC Press
ISBN: 1482271419
Category : Architecture
Languages : en
Pages : 391

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Book Description
A wide ranging and up-to-date review of experience of tunnelling contracts, particularly those for sewerage and drainage tunnels. The review is based on the 6th edition of the ICE Conditions of Contract, but it takes note of new forms of contract which are leading towards less adversarial contractual relations.^

Innovation and the Rise of the Tunnelling Industry

Innovation and the Rise of the Tunnelling Industry PDF Author: Graham West
Publisher: Cambridge University Press
ISBN: 9780521673358
Category : Science
Languages : en
Pages : 376

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Book Description
This book studies the historical development of the tunnelling industry, detailing it's technical innovations.

Tunnelling. A Decade of Progress. GeoDelft 1995-2005

Tunnelling. A Decade of Progress. GeoDelft 1995-2005 PDF Author: Adam Bezuijen
Publisher: CRC Press
ISBN: 9781439834268
Category : Technology & Engineering
Languages : en
Pages : 314

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Book Description
Following years of research, the first bored tunnel in soft soil in the Netherlands, the Tweede Heinenoord tunnel, was completed in 1998. Since then, Dutch engineers have increased their knowledge of soft soil tunnelling, with a significant and important part of this research being carried out by GeoDelft, the Dutch National Institute of Geo-Engineering. This book contains the most important publications by GeoDelft on the subject of soft soil tunnelling, focusing on the period from 1992 to the present, it is divided into four main headings: field measurements; grout behaviour; model testing; and numerical analysis. This impressive overview of the progress made in the Netherlands in soft soil tunnelling research over more than a decade is a valuable resource to those working in soft soil tunnelling worldwide.

Tunnel Boring Machines: Trends in Design and Construction of Mechanical Tunnelling

Tunnel Boring Machines: Trends in Design and Construction of Mechanical Tunnelling PDF Author: A. Schulter
Publisher: CRC Press
ISBN: 1000100065
Category : Technology & Engineering
Languages : en
Pages : 280

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Book Description
In the past ten years there was a worldwide trend towards increased use of Tunnel Boring Machines (TBM's). This trend covers a broad variety of applications ranging both from small diameters for sewers and other utilities to large diameters for double track railway and even three-lane highway tunnels. The response to this has been the development of both hard rock machines in the direction for application in soft ground, and soft ground TBM's to be used in soft rock. Parallel to the technical development of TBM's towards applications for longer tunnels, running through changing geological conditions, there are needs for the development of lining methods. 'TBM Tunnel Trends' an international lecture serie collection, aims to present the latest scientific and practical state of the art of TBM tunnelling, taking into consideration interactions between machinery and lining. 26 international highly recognized papers.