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An electrostatic force microscope was used to write and image localized dots of charge in a double barrier CeO2/Si/CeO2/Si(111) structure. By applying a relatively large tip voltage and reducing the tip to sample separation to 3–5 nm, charge dots 60–200 nm full width at half maximum of both positive and negative charge have been written. The total stored charge is found to be Q = ±(20–200)e per charge dot. These dots of charge are shown to be stable over periods of time greater than 24 h, with an initial charge decay time constant of tau ~ 9.5 h followed by a period of much slower decay with tau > 24 h. The dependence of dot size and total stored charge on various writing parameters such as tip writing bias, tip to sample separation, and write time is examined.

An electrostatic force microscope was used to write and image localized dots of charge in a double barrier CeO2/Si/CeO2/Si(111) structure. By applying a relatively large tip voltage and reducing the tip to sample separation to 3–5 nm, charge dots 60–200 nm full width at half maximum of both positive and negative charge have been written. The total stored charge is found to be Q = ±(20–200)e per charge dot. These dots of charge are shown to be stable over periods of time greater than 24 h, with an initial charge decay time constant of tau ~ 9.5 h followed by a period of much slower decay with tau > 24 h. The dependence of dot size and total stored charge on various writing parameters such as tip writing bias, tip to sample separation, and write time is examined.

Using electron beam evaporation, a Si/CeO2/Si(111) structure has been grown in a molecular beam epitaxy machine. In situ low energy electron diffraction, cross sectional transmission electron microscopy, selected area diffraction, and atomic force microscopy have been used to structurally characterize the overlying silicon layer and show it to be single crystalline and epitaxially oriented. Rutherford backscattering and energy dispersive x-ray analysis have been used to confirm the presence of a continuous 23 Å CeO2 layer at the interface. Rutherford backscattering and x-ray photoemission spectroscopy show an additional presence of cerium both at the exposed silicon surface and incorporated in low levels (~ 1%) within the silicon film, suggesting a growth mechanism with cerium riding atop the silicon growth front leaving behind small amounts of cerium incorporated in the growing silicon crystal.

Using electron beam evaporation, a Si/CeO2/Si(111) structure has been grown in a molecular beam epitaxy machine. In situ low energy electron diffraction, cross sectional transmission electron microscopy, selected area diffraction, and atomic force microscopy have been used to structurally characterize the overlying silicon layer and show it to be single crystalline and epitaxially oriented. Rutherford backscattering and energy dispersive x-ray analysis have been used to confirm the presence of a continuous 23 Å CeO2 layer at the interface. Rutherford backscattering and x-ray photoemission spectroscopy show an additional presence of cerium both at the exposed silicon surface and incorporated in low levels (~ 1%) within the silicon film, suggesting a growth mechanism with cerium riding atop the silicon growth front leaving behind small amounts of cerium incorporated in the growing silicon crystal.

The electrical characteristics of various size tunnel switch diode devices, composed of Al/SiO2/n-Si/p+-Si layers, which operate with a range of parameters (such as current densities in excess of 104 A/cm2) that stress the oxide layer far beyond the levels used in typical thin oxide metal-oxide semiconductor research have been examined. It is found that the first time a large current and electric field are applied to the device, a "forming" process enhances transport through the oxide in the vicinity of the edges of the gate electrode, but the oxide still retains its integrity as a tunnel barrier. The device operation is relatively stable to stresses of greater than 107 C/cm2 areally averaged, time-integrated charge injection. Duplication and characterization of these modified oxide tunneling properties was attempted using scanning tunneling microscopy (STM) to stress and probe the oxide. Electrical stressing with the STM tip creates regions of reduced conductivity, possibly resulting from trapped charge in the oxide. Lateral variations in the conductivity of the unstressed oxide over regions roughly 20–50 nm across were also found.

The electrical characteristics of various size tunnel switch diode devices, composed of Al/SiO2/n-Si/p+-Si layers, which operate with a range of parameters (such as current densities in excess of 104 A/cm2) that stress the oxide layer far beyond the levels used in typical thin oxide metal-oxide semiconductor research have been examined. It is found that the first time a large current and electric field are applied to the device, a "forming" process enhances transport through the oxide in the vicinity of the edges of the gate electrode, but the oxide still retains its integrity as a tunnel barrier. The device operation is relatively stable to stresses of greater than 107 C/cm2 areally averaged, time-integrated charge injection. Duplication and characterization of these modified oxide tunneling properties was attempted using scanning tunneling microscopy (STM) to stress and probe the oxide. Electrical stressing with the STM tip creates regions of reduced conductivity, possibly resulting from trapped charge in the oxide. Lateral variations in the conductivity of the unstressed oxide over regions roughly 20–50 nm across were also found.

Uniform heating of tumor tissue to therapeutic temperatures without damaging surrounding normal tissue is required for optimal local heat therapy of cancer. This paper describes an algorithm for online computer control that will allow the therapist to minimize the standard deviation of measured intratumoral temperatures. The method is applicable to systems incorporating multiple surface and/or interstitial applicators delivering microwave, radiofrequency, or ultrasonic power and operating under the control of a small computer. The essential element is a novel predictive-adaptive control algorithm that infers relevant thermal parameters from the responses of multiple temperature sensors, as each of the power applicators is briefly turned off. Applied power and effective perfusion are estimated from transient slope changes of the temperature-time curves for each sensor. By substituting these values into a system of linear equations derived from the bio-heat transfer equation, the small computer can calculate the optimal allocation of power among the various applicators (“knob settings”) to generate most uniform intratumoral temperature distribution with the desired mean, or minimum, tumor temperature.

The condition of furnace fuel oils in long-term shore storage, pumping trials conducted in depot pipe lines and limited trials in ships are described. Considerable difficulties were experienced in organising sea trials as the ships which could be allocated for the purpose all had other commitments of higher priority and the information obtained was therefore very limited. The large scale pumping trials in depots were sufficiently comprehensive and a good deal of information became available as a result. These trials inevitably suffer from the disadvantage that the temperature of the fuel cannot be adjusted to any required level before the trial and pipelines during the trial are exposed to the prevailing air temperatures. In addition, the pipes may have been in use for some years and their internal condition can only be imagined. It was decided that a rig should be constructed which would be large enough to reproduce the actual conditions which might exist in a small ship, yet be small enough for the essential parts to be housed in a cold room., ADM-62-325

Diffusion takes place in the system Mn(x)O by counter diffusion of magnesium and manganese ions. The presence of electron holes causes a Kirkendall effect not detectable by marker movement since the oxygen lattice is essentially rigid. (The magnesium ion flux is equal to the flux of the manganese ions plus cation vacancies). Since this effect was small, it was neglected under the conditions of the diffusion experiments. The activation energy for diffusion was not concentration dependent over the range tested.

The recovery of creep-resistant substructure of rutile in a vacuum of .00005 torr, has been studied at temperatures of 1000, 1020, and 1040C. Compressive specimens were crept under a stress of sigma sub o = 3000 psi to a strain of epsilon sub c = 0.051 early in the secondary state of creep, and then allowed to recover for varying periods of time under a reduced stress of sigma sub r = 300 psi. Recovery was detected by the increased creep strain which occurred upon reapplication of sigma sub o. Experimental evidence supports the model that the recovery mechanism involves the sweeping out of dislocation barriers within the material by the migration of dislocation walls or sub-boundaries. The results indicate that the recovery of creep-resistant substructure under reduced stress is the same in air and in a vacuum, but the recovery process involving creep at constant stress would be different.

This study seeks to undertake an investigation of the extent to which federal government compensation policies have attempted to reduce differences between the salaries and wages of federal employees and those of their counterparts in similar positions in the private sector. In this respect, the study will attempt to determine why the federal government has found it increasing�ly difficult to bridge the gap between the salaries of its em�ployees and those of the private sector as stipulated by the Federal Pay Comparability Act of 1970. Also this study will assess the ways by which such policies can be revised to insure that federal employees enjoy similar compensation benefits as their counterparts in comparable positions in the private sector. This study concludes that the federal pay comparability process, though desirable, is fraught with major defects that need to be carefully examined and corrected for the process to serve the purpose for which it was designed. In this light, vigorous checks and balances must be introduced and en�forced in both sectors to ensure pay comparability. Also, the comparability process itself must be redefined to eliminate the confusion that currently exists between the positive and normative aspects of the process. Finally, compen�sation relationships between the public and private sectors should be reassessed periodically from a different perspective than that used in the comparability process. Taken together, this study utilized information from a vast array of sources such as books, journals, dissertations, theses, congressional documents, magazines and newspapers.

The primary intent of this thesis is to assess what role the traditional rulers will play in the new federal plan of the government of Nigeria. An attempt has been made to bring to the fore how the role of traditional rulers has changed greatly be tween the period 1800 to 1978. These changes became imperative because of the social, economic and political developments of Nigeria, which dictate that traditional rulers should not participate directly in partisan politics as was hitherto the case. The paper examines the recent demand for the abolition of the institution of traditional rulers. However, the examination shows that the majority of Nigerians still want the services of traditional rulers as leaders of the various communities, who represent symbols of unity. The results point to the fact that whatever party comes into power, it will need the assistance of traditional rulers to serve as a link between the government and the masses. The existence of large scale illiteracy and lack of effective means of direct communication between the government and the people justify the link provided by the traditional rulers. The relationship between the traditional rulers and government should be supplementary, advising the government when that advice is needed. In their areas, they should be the custodians of the customs and tradition of their people. In times of national crisis, traditional rulers collectively will use their fatherly influence and mediate between the varying factions and avert complete anarchy in the country. The main sources of information were Nigerian newspapers which included the New Nigerian, the Daily and Sunday Times, and the West Africa weekly publication. Also, a wide variety of secondary information, books, periodicals, reports and unpublished materials was used.

Petitioners ask that Governor Matteson pardon Lee, who was convicted of larceny in the November term, 1855, at the Sangamon County Circuit Court, and was later sentenced by Judge Davis to one year in the state penitentiary. Petitioners state that although Lee may have been guilty of stealing the $26 as alleged, they believe that it was his first crime and that he will be an "honest & upright man in the future." An endorsement on the back of the petition reads: "Pardoned Jany 24/56." Additional details may be found in: The Law Practice of Abraham Lincoln: Complete Documentary Edition.