scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Phd by thesis

01 Apr 1988-Nature (Nature Publishing Group)-Vol. 332, Iss: 6166, pp 676-676
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Content maybe subject to copyright    Report

Citations
More filters
Journal ArticleDOI
TL;DR: In this article, instanton Floer homology groups for a pair consisting of a compact oriented 3-manifold with boundary and a Lagrangian submanifolds of the moduli space of flat SU(2)connections over the boundary are defined.
Abstract: In this paper we define instanton Floer homology groups for a pair consisting of a compact oriented 3–manifold with boundary and a Lagrangian submanifold of the moduli space of flat SU(2)–connections over the boundary. We carry out the construction for a general class of irreducible, monotone boundary conditions. The main examples of such Lagrangian submanifolds are induced from a disjoint union of handle bodies such that the union of the 3–manifold and the handle bodies is an integral homology 3–sphere. The motivation for introducing these invariants arises from our program for a proof of the Atiyah–Floer conjecture for Heegaard splittings. We expect that our Floer homology groups are isomorphic to the usual Floer homology groups of the closed 3–manifold in our main example and thus can be used as a starting point for an adiabatic limit argument.

67 citations


Cites background from "Phd by thesis"

  • ...Assertion (vi) is a result of Froyshov [11]....

    [...]

Journal ArticleDOI
06 Jun 2010-Small
TL;DR: This study explores a number of low-viscosity glass-forming polymers for their suitability as high-speed materials in electrohydrodynamic (EHD) lithography, and significantly reduces the patterning time compared to earlier approaches.
Abstract: This study explores a number of low-viscosity glass-forming polymers for their suitability as high-speed materials in electrohydrodynamic (EHD) lithography. The use of low-viscosity polymer films significantly reduces the patterning time (to below 10 s) compared to earlier approaches, without compromising the high fidelity of the replicated structures. The rapid pace of this process requires a method to monitor the completion of EHD pattern formation. To this end, the leakage current across the device is monitored and the sigmoidal shape of the current curve is correlated with the various stages of EHD pattern formation.

67 citations

Journal ArticleDOI
TL;DR: In this paper, the authors show that the Gutzwiller trace formula is not applicable for the phase-space dynamics near the bouncing-ball orbits, and they show that a whole region in phase space surrounding the marginal stable family acts, semiclassically, like a stable island with boundaries being explicitly -dependent.
Abstract: The impression gained from the literature published to date is that the spectrum of the stadium billiard can be adequately described, semiclassically, by the Gutzwiller periodic orbit trace formula together with a modified treatment of the marginally stable family of bouncing-ball orbits. I show that this belief is erroneous. The Gutzwiller trace formula is not applicable for the phase-space dynamics near the bouncing-ball orbits. Unstable periodic orbits close to the marginally stable family in phase space cannot be treated as isolated stationary phase points when approximating the trace of the Green's function. Semiclassical contributions to the trace show an -dependent transition from hard chaos to integrable behaviour for trajectories approaching the bouncing-ball orbits. A whole region in phase space surrounding the marginal stable family acts, semiclassically, like a stable island with boundaries being explicitly -dependent. The localized bouncing-ball states found in the billiard derive from this semiclassically stable island. The bouncing-ball orbits themselves, however, do not contribute to individual eigenvalues in the spectrum. An EBK-like quantization of the regular bouncing-ball eigenstates in the stadium can be derived. The stadium billiard is thus an ideal model for studying the influence of almost regular dynamics near marginally stable boundaries on quantum mechanics. The behaviour is generically found at the border of classically stable islands in systems with a mixed phase-space structure.

67 citations


Cites background from "Phd by thesis"

  • ...in the cardioid billiard [49, 48], in the wedge billiard [40, 42] and in the Anisotropic Kepler Problem [1, 50]....

    [...]

  • ...The problem of finding a “good” symbolic dynamics for the stadium [39, 40] might be a consequence of this fundamental dilemma....

    [...]

Journal ArticleDOI
TL;DR: In this article, a chiral iridium N,P complex with sterically demanding aryl substituents was synthesized and used in the asymmetric hydrogenation of difficult substrates.
Abstract: Using a flexible synthesis, new chiral iridium N,P complexes with sterically demanding aryl substituents were synthesized and used in the asymmetric hydrogenation of difficult substrates. Unprecedented enantioselectivities were obtained in the asymmetric hydrogenation of α-substituted α,β-unsaturated esters and dihydronaphthalenes. The variety of aryl substituents incorporated into the catalyst has made it possible to obtain useful structure selectivity relationships for important classes of substrates.

67 citations


Cites background from "Phd by thesis"

  • ...[77] Although this concept did not allow for the application of N,P ligand complexes forming a six-membered chelate ring, it showed that the conversion can be significantly increased for catalysts which in general show reactivity for the analogous methyl ester 3....

    [...]

  • ...Substrates containing a pyridine, primary amine or diene unit, which have been recognized as challenging substrates under base-free conditions, [24, 77, 118] also showed significantly reduced catalyst reactivity was observed under base-promoted conditions (6....

    [...]

  • ...[77] In the course of this study considerable efforts were made to find a system which allows for the highly selective hydrogenation of methyl (2E,4E)-2,4-dimethylhexa-2,4-dienoate (3....

    [...]

  • ...[77] In hydrogenation experiments no reactivity of this dinuclear cluster for α,β-unsaturated nitrile 6....

    [...]

Journal ArticleDOI
TL;DR: Theorems on the existence of minimal models with the same invariants as the minimal model of the Jacobian elliptic curve are proved and simple algorithms for minimising a given model are provided, valid over general number fields.
Abstract: In this paper we consider models for genus one curves of degree n for n = 2, 3 and 4, which arise in explicit n-descent on elliptic curves. We prove theorems on the existence of minimal models with the same invariants as the minimal model of the Jacobian elliptic curve and provide simple algorithms for minimising a given model, valid over general number fields. Finally, for genus one models defined over Q, we develop a theory of reduction and again give explicit algorithms for n = 2, 3 and 4.

67 citations


Cites methods from "Phd by thesis"

  • ...Following the treatment in Womack’s thesis [Wo], we deduce the Minimisation Theorem for n = 4 from the Minimisation Theorem for n = 2....

    [...]

  • ...Earlier work on 4-coverings, including [Wo] and [Sik], used pairs of symmetric matrices rather than pairs of quadrics....

    [...]

References
More filters
Journal ArticleDOI
TL;DR: A new family of highly fluorescent indicators has been synthesized for biochemical studies of the physiological role of cytosolic free Ca2+ using an 8-coordinate tetracarboxylate chelating site with stilbene chromophores that offer up to 30-fold brighter fluorescence.

21,582 citations


"Phd by thesis" refers background in this paper

  • ...members of this group were produced by Tsien and colleagues [1, 10, 11]....

    [...]

  • ...The introduction of Ca 2+ -sensitive fluorescent dyes more than twenty years ago and their permanent improvement [10] enabled investigators to gain unprecedented insights into the mechanisms of cellular signalling....

    [...]

ReportDOI
01 Nov 1990
TL;DR: This report will establish methods for performing a domain analysis and describe the products of the domain analysis process to illustrate the application of domain analysis to a representative class of software systems.
Abstract: : Successful Software reuse requires the systematic discovery and exploitation of commonality across related software systems. By examining related software systems and the underlying theory of the class of systems they represent, domain analysis can provide a generic description of the requirements of that class of systems and a set of approaches for their implementation. This report will establish methods for performing a domain analysis and describe the products of the domain analysis process. To illustrate the application of domain analysis to a representative class of software systems, this report will provide a domain analysis of window management system software.

4,420 citations

Journal ArticleDOI
TL;DR: The straw person model (SPM) as mentioned in this paper has been proposed to explain the orientation effects of active galactic nuclei (AGN) and quasars in the line of sight (LOS) images.
Abstract: Because the critical central regions of Active Galactic Nuclei (AGN) and quasars are strongly nonspherical but spatially unresolved, orientation effects have been the source of much confusion. In fact, it now appears that much of the variety in AGN types is just the result of varying orientation relative to the line of sight. We can define an extreme hypothesis,, the straw person model (SPM), in which there are two basic types of AGN: the radio quiets and the radio louds. For each type there is a range in intrinsic luminosity, and the luminosity controls some properties such as the Fanaroff and Riley classes. However, at a given intrinsic luminosity, all other properties such as spectroscopic classification and VLBI component speeds are ascribed to orientation. This model is only a caricature of the unification idea, and is already ruled out on many grounds, but it will be useful for organizing the discussion. I’ll describe what I consider to be convincing evidence that orientation effects are important and widespread. The true situation may be in some sense half way between the SPM and the hypothesis that orientation doesn’t affect classification at aIl. To us optimists, the orienration cup is half full rather than half empty. Although it is too soon to say for sure, the hypothesis that most objects’ classifications would be different if seen from other directions is a tenable one today.

4,005 citations

Journal ArticleDOI
TL;DR: This Review assembles the current knowledge on the isolation of microfibrillated cellulose from wood and its application in nanocomposites; the preparation of nanocrystalline cellulose and its use as a reinforcing agent; and the biofabrication of bacterial nanocellulose, as well as its evaluation as a biomaterial for medical implants.
Abstract: Cellulose fibrils with widths in the nanometer range are nature-based materials with unique and potentially useful features. Most importantly, these novel nanocelluloses open up the strongly expanding fields of sustainable materials and nanocomposites, as well as medical and life-science devices, to the natural polymer cellulose. The nanodimensions of the structural elements result in a high surface area and hence the powerful interaction of these celluloses with surrounding species, such as water, organic and polymeric compounds, nanoparticles, and living cells. This Review assembles the current knowledge on the isolation of microfibrillated cellulose from wood and its application in nanocomposites; the preparation of nanocrystalline cellulose and its use as a reinforcing agent; and the biofabrication of bacterial nanocellulose, as well as its evaluation as a biomaterial for medical implants.

3,452 citations

Journal ArticleDOI
TL;DR: The solid electrolyte interphase (SEI) is a protecting layer formed on the negative electrode of Li-ion batteries as a result of electrolyte decomposition, mainly during the first cycle as discussed by the authors.

2,386 citations