146 research outputs found
Civil Rights and Suffrage: Myra Bradwell\u27s Struggle for the Equal Citizenship for Women
After the Civil War, while the nation debated the range of rights which would be secured to the freedmen, the women\u27s rights movement worked to insure that women would also receive equal rights, particularly the right to vote. When the Fourteenth and Fifteenth Amendments did not enfranchise women, many women who had fought against slavery and for universal suffrage felt betrayed. The Republican Party\u27s refusal to include women\u27s rights in the party platform deepened the sense of betrayal and forced suffragists I to take up their cause for equal rights of citizenship separately from the freedmen. Two inequities in particular animated women\u27s rights activists\u27 fight: married women\u27s civil death in marriage, and all women\u27s lack of political rights
Measurement & Prediction of Phase Behaviour of Carbon Dioxide Mixtures
Acquiring a comprehensive understanding of the behaviour of carbon dioxide under reservoir conditions is essential for optimizing its usage in enhanced oil recovery (EOR) and for developing sequestration schemes. In order to obtain this understanding, it is necessary to study the physical properties and phase behaviour of mixtures of carbon dioxide with hydrocarbons and brines under conditions of high pressure. In this work we are addressing both the experimental and the theoretical aspects of this problem. A new apparatus, based on the static-analytical method, has been developed to measure phase equilibrium. The equipment comprises a high-pressure cell with sapphire windows for visual observation and phase sampling, with on-line gas chromatography analysis, for measuring the phase compositions. The experimental work is complemented with a theoretical modelling for these mixtures, using the statistical association fluid theory for potentials of variable range (SAFT-VR). As an example of the predictive capabilities of the equation, the fluid phase behaviour of the mixture (carbon dioxide + n-decane) is presented
Inventaire et suivi des ressources en eau de surface de la Basse Terre : compte rendu d'activité et résultats obtenus en 1985
Shallow Gas Hydrate Accumulations at a Nigerian Deepwater Pockmark—Quantities and Dynamics
The evolution of submarine pockmarks is often related to the ascent of fluid from the subsurface. For pockmarks located within the gas hydrate stability zone, methane oversaturation can result in the formation of gas hydrates in the sediment. An ~600 m‐wide sea floor depression in deep waters offshore Nigeria, Pockmark A, was investigated for distributions and quantities of shallow gas hydrates, origins of hydrocarbons, and time elapsed since the last major fluid ascent event. For the first time, pressure coring of shallow sediments and drilling of more than 50 m‐long cores with the sea floor drill rig MARUM‐MeBo70 were conducted in this pockmark. Unusually, high hydrate saturations of up to 51% of pore volume in the uppermost 2.5 m of sediment in the pockmark center substantiate that deepwater pockmarks are a relevant methane reservoir. Molecular and stable C and H isotopic compositions suggest that thermogenic hydrocarbons and secondary microbial methane resulting from petroleum biodegradation are injected into shallower sediments and mixed with primary microbial hydrocarbons. Two independent pore water chloride and sulfate modeling approaches suggest that a major methane migration event occurred during the past one to three centuries. A rough sea floor topography within the pockmark most likely results from combined sediment removal through ascending gas bubbles, hydrate clogging and deflection of migration pathways, gas pressure build‐up, and hydrate sea floor detachment. This study shows for the first time the chronological interrelationship between gas migration events, hydrate formation, and sea floor shaping in a deep sea pockmark
First Detection of Mycobacterium ulcerans DNA in Environmental Samples from South America
The occurrences of many environmentally-persistent and zoonotic infections are driven by ecosystem changes, which in turn are underpinned by land-use modifications that alter the governance of pathogen, biodiversity and human interactions. Our current understanding of these ecological changes on disease emergence however remains limited. Buruli ulcer is an emerging human skin disease caused by the mycobacterium, Mycobacterium ulcerans, for which the exact route of infection remains unclear. It can have a devastating impact on its human host, causing extensive necrosis of the skin and underlying tissue, often leading to permanent disability. The mycobacterium is associated with tropical aquatic environments and incidences of the disease are significantly higher on floodplains and where there is an increase of human aquatic activities. Although the disease has been previously diagnosed in South America, until now the presence of M. ulcerans DNA in the wild has only been identified in Australia where there have been significant outbreaks and in western and central regions of Africa where the disease is persistent. Here for the first time, we have identified the presence of the aetiological agent's DNA in environmental samples from South America. The DNA was positively identified using Real-time Polymerase Chain Reaction (PCR) on 163 environmental samples, taken from 23 freshwater bodies in French Guiana (Southern America), using primers for both IS2404 and for the ketoreductase-B domain of the M. ulcerans mycolactone polyketide synthase genes (KR). Five samples out of 163 were positive for both primers from three different water bodies. A further nine sites had low levels of IS2404 close to a standard CT of 35 and could potentially harbour M. ulcerans. The majority of our positive samples (8/14) came from filtered water. These results also reveal the Sinnamary River as a potential source of infection to humans. © 2014 Morris et al
Inter-Comparison of the Spatial Distribution of Methane in the Water Column From Seafloor Emissions at Two Sites in the Western Black Sea Using a Multi-Technique Approach
Understanding the dynamics and fate of methane (CH 4 ) release from oceanic seepages on margins and shelves into the water column, and quantifying the budget of its total discharge at different spatial and temporal scales, currently represents a major scientific undertaking. Previous works on the fate of methane escaping from the seafloor underlined the challenge in both, estimating its concentration distribution and identifying gradients. In April 2019, the Envri Methane Cruise has been conducted onboard the R/V Mare Nigrum in the Western Black Sea to investigate two shallow methane seep sites at ∼120 m and ∼55 m water depth. Dissolved CH 4 measurements were conducted with two continuous in-situ sensors: a membrane inlet laser spectrometer (MILS) and a commercial methane sensor (METS) from Franatech GmbH. Additionally, discrete water samples were collected from CTD-Rosette deployment and standard laboratory methane analysis was performed by gas chromatography coupled with either purge-and-trap or headspace techniques. The resulting vertical profiles (from both in situ and discrete water sample measurements) of dissolved methane concentration follow an expected exponential dissolution function at both sites. At the deeper site, high dissolved methane concentrations are detected up to ∼45 m from the seabed, while at the sea surface dissolved methane was in equilibrium with the atmospheric concentration. At the shallower site, sea surface CH 4 concentrations were four times higher than the expected equilibrium value. Our results seem to support that methane may be transferred from the sea to the atmosphere, depending on local water depths. In accordance with previous studies, the shallower the water, the more likely is a sea-to-atmosphere transport of methane. High spatial resolution surface data also support this hypothesis. Well localized methane enriched waters were found near the surface at both sites, but their locations appear to be decoupled with the ones of the seafloor seepages. This highlights the need of better understanding the processes responsible for the transport and transformation of the dissolved methane in the water column, especially in stratified water masses like in the Black Sea
Geochemical Dynamics of the Natural-Gas Hydrate System in the Sea of Marmara, Offshore Turkey
- …