Phd by thesis
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
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TL;DR: In this article, an experimental study of C60-based spin valves is presented and their behavior is modeled with spin-polarized tunneling via multiple intermediate states with a Gaussian energy distribution.
Abstract: Carbon-based, molecular semiconductors offer several attractive attributes for spintronics, such as exceptionally weak spin-orbit coupling and compatibility with bottom-up nanofabrication. In spite of the promising properties of organic spin valves, however, the physical mechanisms governing spin-polarized conduction remain poorly understood. An experimental study of C60-based spin valves is presented and their behavior is modeled with spin-polarized tunneling via multiple intermediate states with a Gaussian energy distribution. It is shown that, analogous to conductivity mismatch in the diffusive regime, the magnetoresistance decreases with the number of intermediate tunnel steps, regardless of the value of the spin lifetime. This mechanism has been largely overlooked in previous studies of organic spin valves. In addition, using measurements of the temperature and bias dependence of the magnetoresistance, inhomogeneous magnetostatic fields resulting from interfacial roughness are identified as a source for spin relaxation and dephasing. These findings constitute a comprehensive understanding of the processes underlying spin-polarized transport in these structures and shed new light on previous studies of organic spin valves.
81 citations
Cites background from "Phd by thesis"
...For the Al2O3 barrier, we estimate an extinction coefficient of evanescent states κ ≈ 3 nm−1, based on measurements of the resistance area product as a function of thickness of similar Al2O3 tunnel contacts,[31] while the thickness of the barrier dA is 2 nm....
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TL;DR: In this paper, the electrical, optical, morphological and mechanical properties of both types of ITO layers are compared and the influence of the sintering temperature is also discussed.
81 citations
Cites background from "Phd by thesis"
...The detailed preparation of the ITO powder can be found in [3,4,8]....
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...An increase of the carrier concentration shifts the onset of the absorbance to lower wavelength [4]....
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...However in this case the conductivity slightly decreases [4,7]....
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...Nevertheless the route is a promising alternative for some forthcoming development because of the lower deposition cost and particularly because of the possibility to process layers at room temperature on plastic substrates [4,7]....
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TL;DR: In this article, a review of recent progress in the theoretical description of correlation and quantum fluctuation phenomena in charge transport through single molecules, quantum dots and quantum wires is presented, relating to cotunneling, pair tunneling, adiabatic quantum pumping, charge and spin fluctuations and inhomogeneous Luttinger liquids.
Abstract: We review recent progress in the theoretical description of correlation and quantum fluctuation phenomena in charge transport through single molecules, quantum dots and quantum wires. Various physical phenomena are addressed, relating to cotunneling, pair-tunneling, adiabatic quantum pumping, charge and spin fluctuations, and inhomogeneous Luttinger liquids. We review theoretical many-body methods to treat correlation effects, quantum fluctuations, non-equilibrium physics, and the time evolution into the stationary state of complex nanoelectronic systems.
81 citations
Posted Content•
28 Jul 1998TL;DR: Within the standard models of particle physics and cosmology, the authors have calculated the big-bang prediction for the primordial abundance of He to a theoretical uncertainty of less than $0.0002, improving the current theoretical precision by a factor of 10.
Abstract: Within the standard models of particle physics and cosmology we have calculated the big-bang prediction for the primordial abundance of \he to a theoretical uncertainty of less than $0.1 \pct$ $(\delta Y_P < \pm 0.0002)$, improving the current theoretical precision by a factor of 10. At this accuracy the uncertainty in the abundance is dominated by the experimental uncertainty in the neutron mean lifetime, $\tau_n = 885.4 \pm 2.0 sec$. The following physical effects were included in the calculation: the zero and finite-temperature radiative, Coulomb and finite-nucleon-mass corrections to the weak rates; order-$\alpha$ quantum-electrodynamic correction to the plasma density, electron mass, and neutrino temperature; and incomplete neutrino decoupling. New results for the finite-temperature radiative correction and the QED plasma correction were used. In addition, we wrote a new and independent nucleosynthesis code designed to control numerical errors to be less than 0.1\pct. Our predictions for the \EL[4]{He} abundance are presented in the form of an accurate fitting formula. Summarizing our work in one number, $ Y_P(\eta = 5\times 10^{-10}) = 0.2462 \pm 0.0004 (expt) \pm < 0.0002 (theory)$. Further, the baryon density inferred from the Burles-Tytler determination of the primordial D abundance, $\Omega_B h^2 = 0.019\pm 0.001$, leads to the prediction: $Y_P = 0.2464 \pm 0.0005 (D/H) \pm < 0.0002 (theory) \pm 0.0005 (expt)$. This ``prediction'' and an accurate measurement of the primeval \he abundance will allow an important consistency test of primordial nucleosynthesis.
81 citations
Cites background from "Phd by thesis"
...Kernan and Krauss reported finding a significant numerical error in the standard code [11, 30], δYP = 0....
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...Over the years, theoretical study of Helium formation has been intense, with the following effects being considered: Coulomb and radiative corrections to the weak rates [8, 9, 10, 11, 12, 13], BBN code numerical errors [11], nuclear reaction rate uncertainties [14, 15], finite-temperature QED plasma corrections [8, 16], the effect of finite-nucleon mass [17, 18], and incomplete neutrino decoupling [8, 19]....
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TL;DR: In this article, it was shown that only one of the previously used schemes correctly implements the cutoff on eigenvalues of the Dirac operator, and it acts in the sense of screening Newton's constant, and that Kahler fermions give the same contribution to the running of the cosmological and Newton constant as four Dirac spinors.
Abstract: We investigate some aspects of the renormalization group flow of gravity in the presence of fermions, which have remained somewhat puzzling so far. The first is the sign of the fermionic contribution to the running of Newton's constant, which depends on details of the cutoff. We argue that only one of the previously used schemes correctly implements the cutoff on eigenvalues of the Dirac operator, and it acts in the sense of screening Newton's constant. We also show that K\"ahler fermions give the same contribution to the running of the cosmological and Newton constant as four Dirac spinors. We then calculate the graviton contributions to the beta functions by imposing the cutoffs on the irreducible spin components of the tetrad. In this way we can probe the gauge dependence of the off-shell flow. The results resemble closely those of the metric formalism, except for an increased scheme-- and (off shell) gauge--dependence.
81 citations
Cites background from "Phd by thesis"
...5 The agreement between cutoffs IIa and IIb for α = 1 had been noticed before in [38]....
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References
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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]....
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...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....
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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
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
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
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