Search results for "Formula"

The Basics of Nuclear Chemistry and Radiochemistry: An Introduction to Nuclear Transformations and Radioactive Emissions

2019

Radiopharmaceutical chemistry and nuclear medicine make use of radioactive elements and compounds labeled with them. This chapter describes the fundamentals of radioactivity in the context of life sciences. It addresses principal questions such as: What is the composition of an atomic nucleus and what are the forces which hold nucleons bound within the nucleus? Even so, some nuclei are stable, and many others are not—why? The fate of unstable nuclei is transforming into more stable nucleon configurations—but what are the basic pathways to do so? What’s going on inside the nucleus? What are the energetics and velocities of these transformations? And finally, the various changes inside the nu…

Rydberg excitation of cold atoms inside a hollow core fiber

2017

We report on a versatile, highly controllable hybrid cold Rydberg atom fiber interface, based on laser cooled atoms transported into a hollow core Kagom\'{e} crystal fiber. Our experiments are the first to demonstrate the feasibility of exciting cold Rydberg atoms inside a hollow core fiber and we study the influence of the fiber on Rydberg electromagnetically induced transparency (EIT) signals. Using a temporally resolved detection method to distinguish between excitation and loss, we observe two different regimes of the Rydberg excitations: one EIT regime and one regime dominated by atom loss. These results are a substantial advancement towards future use of our system for quantum simulat…

Narrow-band pulsed electron source based on near-threshold photoionization of Cs in a magneto-optical trap

2019

The newly developed method of time-of-flight (ToF) momentum microscopy was used to analyse the cold electron emission from a Cs 3D magneto-optical trap (MOT). Three-step resonant photoionization was implemented via two intermediate states (6P3/2 pumped with 852 nm laser and 7S1/2 with 1470 nm) and a tuneable femtosecond Ti:sapphire laser for the final ionization step. The magnetic field of the MOT is switched off during the photoionization step. The natural bandwidth of the fs-laser is reduced to 4 meV using optical spectral filters. Precise tuning of the photon energy makes it possible to observe the transition regime between direct photoemission into the open continuum and field induced i…

Operator splitting methods for American option pricing

2004

Abstract We propose operator splitting methods for solving the linear complementarity problems arising from the pricing of American options. The space discretization of the underlying Black-Scholes Scholes equation is done using a central finite-difference scheme. The time discretization as well as the operator splittings are based on the Crank-Nicolson method and the two-step backward differentiation formula. Numerical experiments show that the operator splitting methodology is much more efficient than the projected SOR, while the accuracy of both methods are similar.

Adaptive discontinuous evolution Galerkin method for dry atmospheric flow

2014

We present a new adaptive genuinely multidimensional method within the framework of the discontinuous Galerkin method. The discontinuous evolution Galerkin (DEG) method couples a discontinuous Galerkin formulation with approximate evolution operators. The latter are constructed using the bicharacteristics of multidimensional hyperbolic systems, such that all of the infinitely many directions of wave propagation are considered explicitly. In order to take into account multiscale phenomena that typically appear in atmospheric flows nonlinear fluxes are split into a linear part governing the acoustic and gravitational waves and a nonlinear part that models advection. Time integration is realiz…

Sustainability of Pension Systems in the Baltic States

2016

Objective: The objective of the paper is to identify how the concept of sustainability is understood and ensured in the pension systems of Estonia, Latvia and Lithuania; and what implications it brings to the performance of pension schemes. Research Design & Methods: Analysis of various conceptual and methodological approaches to the notion of sustainability of pension systems. Comparative analysis of present pension legislation, as well as preceding stage of pension reforms,   accompanied by a number of numerical models. Findings: The understanding of sustainability is limited by narrow ‘fiscal’ meaning in Latvia, compared to more a multifaceted concept that includes the principle of socia…

Notes on the Barometric Formula

2020

The electronic spectrum of pyrrole

1999

The electronic spectrum of pyrrole has been investigated by performing calculations using a hierarchy of coupled-cluster models consisting of CCS, CC2, CCSD, and CC3. Basis-set effects have been investigated by carrying out calculations using correlation-consistent basis sets augmented with functions especially designed for the description of Rydberg states. Oscillator strengths, excited state dipole moments, and second moments of the electronic charge distributions have been used to characterize the electronic transitions and final states. Structures and vibrational frequencies have been calculated for a few selected states, and the importance of distinguishing between vertical and adiabat…

"Pour moi, le goût du soja n'est pas une barrière à la consommation. Et pour vous ?" : Effet de la culture sur les croyances, attitudes et préférence…

2010

Understanding consumers' beliefs, attitudes and sensory preference is the key to a successful development and introduction of a new food. This thesis carried out a series of cross-cultural studies, France vs. Vietnam, on consumers' representation of soy foods and on sensory perception and preference of soy yogurts, a soy derived product recently developed for French market which does not exist on the Vietnamese market. Despite a favourable image of soy in terms of nutrition and health benefices, French participants reported that the barrier to its consumption was the taste of soy. This finding was confirmed by a consumer test in which French participants gave very low hedonic evaluations to…

Effect of simulated gastrointestinal digestion on sialic acid and gangliosides present in human milk and infant formulas.

2011

The effects of simulated gastrointestinal digestion upon sialic acid and gangliosides in infant and follow-on formulas and human milk, as well as their bioaccessibility, have been evaluated. The gastric stage is the step that causes a greater decrease in sialic acid and ganglioside contents. The intestinal stage only decreases the total and individual contents of gangliosides. After gastrointestinal digestion, neither sialic acid nor gangliosides were found in the nonbioaccessible fraction. The highest bioaccessibility (100 × content in soluble fraction after gastrointestinal digestion/total content) of sialic acid is found in human milk (87%), followed by infant formula (77%) and follow-on…