Experimental Investigation of the Recovery of Gas and Oil by Spontaneous Water Imbibition

Imperial Users onl

Confinement of Light in Disordered Photonic Lattices: A New Platform for Waveguidance

A right amount of disorder in the form of refractive index variation has been introduced to achieve transverse localization of light 1D semi-infinite photonic lattices. Presence of longitudinally-invariant transverse disorder opens-up a new waveguiding mechanism.Comment: 3 page

Special L-values of t-motives: a conjecture

We propose a conjecture on special values of $L$-functions in a function field context with positive characteristic coefficients. For $M$ a uniformizable $t$-motive with everywhere good reduction we conjecture a relation between the value of the Goss $L$-function $L(M^\vee, s)$ at $s = 0$ and the uniformization of the abelian $t$-module associated with $M$. When $M$ is a power of the Carlitz $t$-motive the conjecture specializes to a theorem of Anderson and Thakur on Carlitz zeta values. Beyond this case we present numerical evidence.Comment: in International Mathematics Research Notices (2009

Suspending test masses in terrestrial millihertz gravitational-wave detectors: a case study with a magnetic assisted torsion pendulum

Current terrestrial gravitational-wave detectors operate at frequencies above 10 Hz. There is strong astrophysical motivation to construct low-frequency gravitational-wave detectors capable of observing 10 mHz - 10Hz signals. While space-based detectors provide one means of achieving this end, one may also consider terretrial detectors. However, there are numerous technological challenges. In particular, it is difficult to isolate test masses so that they are both seismically isolated and freely falling under the influence of gravity at millihertz frequencies. We investigate the challenges of low-frequency suspension in a hypothetical terrestrial detector. As a case study, we consider a Magnetically Assisted Gravitational-wave Pendulum Intorsion (MAGPI) suspension design. We construct a noise budget to estimate some of the required specifications. In doing so, we identify what are likely to be a number of generic limiting noise sources for terrestrial millihertz gravitational-wave suspension systems (as well as some peculiar to the MAGPI design). We highlight significant experimental challenges in order to argue that the development of millihertz suspensions will be a daunting task. Any system that relies on magnets faces even greater challenges. Entirely mechanical designs such as Zollner pendulums may provide the best path forward.Comment: 6 pages, 4 figure

Application of LANDSAT-2 data to the implementation and enforcement of the Pennsylvania Surface Mining Conservation and Reclamation Act

The author has identified the following significant results. Evaluation of LANDSAT imagery indicates severe limitations in its utility for surface mine land studies. Image stripping resulting from unequal detector response on satellite degrades the image quality to the extent that images of scales larger than 1:125,000 are of limited value for manual interpretation. Computer processing of LANDSAT data to improve image quality is essential; the removal of scanline stripping and enhancement of mine land reflectance data combined with color composite printing permits useful photographic enlargements to approximately 1:60,000

Social movements, violence, and change: the May Movement in Curaçao

(print) x, 175 p. : ill. ; 22 cmPREFACE ix -- 1 SOCIAL MOVEMENTS AND SOCIAL CHANGE The Riot; The May Movement as a Synthesis; Social Movements and Social Change 3 -- 2 CURACAO : HISTORY AND DEVELOPMENT Population Sources; The Impact of the Refinery on Curacao; Curacao's Place Within the Kingdom of the Netherlands 24 -- 3 THE CONTEMPORARY SCENE : SOCIAL CHANGE AND THE RESPONSE TO SOCIAL STRAIN The Population Base and the Stratification System; Politics and Government; Politics and Labor; Personal Politics; The Labor Movement; The Growth of Radical Politics 46 -- 4 THE EMERGENCE OF THE MAY MOVEMENT Labor Unrest; Emergence of the May Movement-Economic Mobilization; Elaboration of the May Movementoliticization; Significance of Internal Conflict; Significance of Structural Setting 68 -- 5 THE MAY MOVEMENT AND SOCIAL CHANGE AND REFORM IN CURACAO Political Change and Reform; Economic Change and Reform; Sociocultural Change and Reform; The Societal Capacity for Reform 96 -- 6 THE MAY MOVEMENT IN THE CONTEXT OF OTHER SOCIAL MOVEMENTS The Nature of Violence and the Direction of Protest; The Importance of Labor in Social Movements in Developing Countries; The May Movement and Racial Disturbances in the United States; The May Movement and Other Western Social Movements; The Consequences of the May Movement for the Curacao of the Future 124 -- APPENDIXES A. The Agreement of Kralendijk B. Conclusions and Recommendations, May 30, 1969 : Report of the Commission for the Investigation of the Causes of the May 30, 1969 Riots in Curacao C. Data Collection 159 -- INDEX 17

Partial-Transfer Absorption Imaging: A versatile technique for optimal imaging of ultracold gases

Partial-transfer absorption imaging is a tool that enables optimal imaging of atomic clouds for a wide range of optical depths. In contrast to standard absorption imaging, the technique can be minimally-destructive and can be used to obtain multiple successive images of the same sample. The technique involves transferring a small fraction of the sample from an initial internal atomic state to an auxiliary state and subsequently imaging that fraction absorptively on a cycling transition. The atoms remaining in the initial state are essentially unaffected. We demonstrate the technique, discuss its applicability, and compare its performance as a minimally-destructive technique to that of phase-contrast imaging.Comment: 10 pages, 5 figures, submitted to Review of Scientific Instrument