Superconducting Surface Impedance under Radiofrequency Field

Based on BCS theory with moving Cooper pairs, the electron states distribution at 0K and the probability of electron occupation with finite temperature have been derived and applied to anomalous skin effect theory to obtain the surface impedance of a superconductor under radiofrequency (RF) field. We present the numerical results for Nb and compare these with representative RF field-dependent effective surface resistance measurements from a 1.5 GHz resonant structure

The collective gyration of a heavy ion cloud in a magnetized plasma

In both the ionospheric barium injection experiments CRIT 1 and CRIT 2, a long duration oscillation was seen with a frequency close to the gyro frequency of barium and a time duration of about one second. A model for the phenomena which was proposed for the CRIT 1 experiment is compared to the results from CRIT 2 which made a much more complete set of measurements. The model follows the motion of a low Beta ion cloud through a larger ambient plasma. The internal field of the model is close to antiparallel to the injection direction v sub i but slightly tilted towards the self polarization direction E sub p = -V sub i by B. As the ions move across the magnetic field, the space charge is continuously neutralized by magnetic field aligned electron currents from the ambient ionosphere, drawn by the divergence in the perpendicular electric field. These currents give a perturbation of the magnetic field related to the electric field perturbation by Delta E/Delta B approximately equal to V sub A. The model predictions agree quite well with the observed vector directions, field strengths, and decay times of the electric and magnetic fields in CRIT 2. The possibility to extend the model to the active region, where the ions are produces in this type of self-ionizing injection experiments, is discussed

An evaluation of exercises for the development of word recognition and word meaning in grade five

Thesis (Ed.M.)--Boston Universit

Implementing Quantum Gates by Optimal Control with Doubly Exponential Convergence

We introduce a novel algorithm for the task of coherently controlling a quantum mechanical system to implement any chosen unitary dynamics. It performs faster than existing state of the art methods by one to three orders of magnitude (depending on which one we compare to), particularly for quantum information processing purposes. This substantially enhances the ability to both study the control capabilities of physical systems within their coherence times, and constrain solutions for control tasks to lie within experimentally feasible regions. Natural extensions of the algorithm are also discussed.Comment: 4+2 figures; to appear in PR

Chapter Three. EED library as a basis for systematic reviews

3.1 Defining Systematic Review Question Priorities 3.2 Determining Relevance to the Systematic Review 3.3 Acquisition of References and Copyright Fair Use Compliance 3.4 Documenting Relevance to the Systematic Review 3.5 Data Extraction for the Systematic Review 3.6 EED Library: Search Results Overview 3.7 Quality Control 3.8 EED Library Statushttps://digitalcommons.wustl.edu/tropicalenteropathybook/1004/thumbnail.jp

Chapter Five. Systematic review results by biomarker classifications

5.1 Markers of Absorption and Permeability Overview 5.2 Markers of Absorption 5.3 Markers of Permeability 5.4 Markers of Digestion 5.5 Markers of Intestinal Inflammation and Intestinal Immune Activation 5.6 Markers of Systemic Inflammation and Systemic Immune Activation 5.7 Markers of Microbial Drivers 5.8 Markers of Nonspecific Intestinal Injury 5.9 Markers of Extra-Small Intestinal Function 5.10 Relationships Between Markers of EED, Including Histopathology 5.11 Relationships between EED Biomarkers and Growth or Other Outcomes of Interesthttps://digitalcommons.wustl.edu/tropicalenteropathybook/1006/thumbnail.jp

Chapter Six. Conclusions and future implications

6.1 Summary of Findings 6.2 Future Biomarker and Diagnostics Researchhttps://digitalcommons.wustl.edu/tropicalenteropathybook/1007/thumbnail.jp

Eddy turbulence, the double mesopause, and the double layer of atomic oxygen

In this study, we consider the impact of eddy turbulence on temperature and atomic oxygen distribution when the peak of the temperature occurs in the upper mesosphere. A previous paper (Vlasov and Kelley, 2010) considered the simultaneous impact of eddy turbulence on temperature and atomic oxygen density and showed that eddy turbulence provides an effective mechanism to explain the cold summer and warm winter mesopause observed at high latitudes. Also, the prevalent role of eddy turbulence in this case removes the strong contradiction between seasonal variations of the O density distribution and the impact of upward/downward motion corresponding to adiabatic cooling/heating of oxygen atoms. Classically, there is a single minimum in the temperature profile marking the location of the mesopause. But often, a local maximum in the temperature is observed in the height range of 85–100 km, creating the appearance of a double mesopause (Bills and Gardner, 1993; Yu and She, 1995; Gusev et al., 2006). Our results show that the relative temperature maximum in the upper mesosphere (and thus the double mesopause) can result from heating by eddy turbulence. According to our model, there is a close connection between the extra temperature peak in the mesosphere and the oxygen atom density distribution. The main feature of the O density height profile produced by eddy turbulence in our model is a double peak instead of a single peak of O density. A rocket experiment called TOMEX confirms these results (Hecht et al., 2004). Applying our model to the results of the TOMEX rocket campaign gives good agreement with both the temperature and oxygen profiles observed. Climatology of the midlatitude mesopause and green line emission shows that the double mesopause and the double layers of the green line emission, corresponding to the double O density height profile, are mainly observed in spring and fall (Yu and She, 1995; Liu and Shepherd, 2006). Further observations of the oxygen atom densities and the double mesopause would improve our understanding of the impact of turbulence on critical mesospheric parameters