Structure and dynamics in protic ionic liquids: a combined optical Kerr-effect and dielectric relaxation spectroscopy study

The structure and dynamics of ionic liquids (ILs) are unusual due to the strong interactions between the ions and counter ions. These microscopic properties determine the bulk transport properties critical to applications of ILs such as advanced fuel cells. The terahertz dynamics and slower relaxations of simple alkylammonium nitrate protic ionic liquids (PILs) are here studied using femtosecond optical Kerr-effect spectroscopy, dielectric relaxation spectroscopy, and terahertz time-domain spectroscopy. The observed dynamics give insight into more general liquid behaviour while comparison with glass-forming liquids reveals an underlying power-law decay and relaxation rates suggest supramolecular structure and nanoscale segregation

The political aspects of institutional developments in the water sector: South Africa and its international river basins

This research set out to develop a deeper theoretical component to the emerging discipline of hydropolitics by studying the political aspects of institutional developments in the water sector. The focal point was the four international river basins that are shared between South Africa and six of its neighbouring states. The study found that while there is a lot of evidence for the securitization of water resource management in South Africa’s international river basins, there are also a number of examples of regimes. The creation of these regimes was driven primarily by threat perceptions relating to state security, mostly during the period of apartheid and the Cold War. These regimes were mostly robust and served as a valuable instrument for the de-escalation of conflict, which was primarily of a high politics nature. Examples of both plus-sum and zero-sum outcomes have been isolated. Plus-sum outcomes arose when the non-hegemonic state chose to view the offer of a regime in terms of national self-interest with four examples of this condition. In all four cases the non-hegemonic state benefited from cooperation with South Africa. Zero-sum outcomes arose when the non-hegemonic state chose to view the offer of a regime in terms of ideology with two examples of this condition. In both cases the non-hegemonic state did not benefit and was sidelined to the extent that they became marginalized and worse off than before. In all cases the hegemonic state benefited from the regime. The research consequently showed that a hydropolitical complex is emerging in Southern Africa, clustered around two international river basins, the Orange and Limpopo, which have been defined as pivotal basins. Both of these basins have reached the limit of their readily available water resources and future development is not possible on any great scale. Four of the most economically developed states in Southern Africa (Namibia, Botswana, Zimbabwe and South Africa) are riparians on these two international river basins, and have been defined as pivotal states. Other less developed countries that share any international river basin with a pivotal state have been defined as an impacted state, because their own development aspirations have been capped through this association. Any international river basin that has at least one of the pivotal states in it has been defined an impacted basin. Finally, this research showed that regimes create a plus-sum outcome in closed international river basins because they reduce the levels of uncertainty and institutionalize the conflict potential. As such regimes are a useful instrument with which to regulate inter-state behavior, leading over time to the development of institutions consisting of rules and procedures.Thesis (DPhil (International Politics))--University of Pretoria, 2005.Political Sciencesunrestricte

The hydropolitics of Southern Africa: the case of the Zambezi river basin as an area of potential co-operation based on Allan's concept of virtual water.

Southern Africa generally has an arid climate and many hydrologists are predicting an increase in water scarcity over time. This research seeks to understand the implications of this in socio-political terms. The study is cross-disciplinary, examining how policy interventions can be used to solve the problem caused by the interaction between hydrology and demography. The conclusion is that water scarcity is not the actual problem, but is perceived as the problem by policy-makers. Instead, water scarcity is the manifestation of the problem, with root causes being a combination of climate change, population growth and misallocation of water within the economy due to a desire for national self-sufficiency in agriculture. The solution lies in the trade of products with a high water content, also known as 'virtual water'. Research on this specific issue is called for by the White Paper on Water Policy for South Africa.Political SciencesM.A. (International Politics

Glasslike Behavior in Aqueous Electrolyte Solutions

When salts are added to water, the viscosity generally increases suggesting the ions increase the strength of the water's hydrogen-bond network. However, infrared pump-probe measurements on electrolyte solutions have found that ions have no influence on the rotational dynamics of water molecules implying no enhance-ment or breakdown of the hydrogen-bond network. Here we report optical Kerr-effect and dielectric relaxa-tion spectroscopic measurements, which have enabled us to separate the effects of rotational and transitional motions of the water molecules. These data show that electrolyte solutions behave like a supercooled liquid approaching a glass transition in which rotational and translational molecular motions are decoupled. It is now possible to understand previously conflicting viscosity data, nuclear magnetic resonance relaxation, and ultrafast infrared spectroscopy in a single unified picture

U.S. DOE Industrial Technologies Program – Technology Delivery Plant-Wide Assessment at PPG Industries, Natrium, WV

PPG and West Virginia University performed a plantwide energy assessment at the PPG’s Natrium, WV chemical plant, an energy-intensive manufacturing facility producing chlor-alkali and related products. Implementation of all the assessment recommendations contained in this report could reduce plant energy consumption by 8.7%, saving an estimated 10,023,192 kWh/yr in electricity, 6,113 MM Btu/yr in Natural Gas, 401,156 M lb/yr in steam and 23,494 tons/yr in coal and reduce carbon dioxide emissions by 241 mm lb/yr. The total cost savings would amount to approximately $2.9 mm/yr. Projects being actively implemented will save$1.7 mm/yr; the remainder are undergoing more detailed engineering study

The-state-of-the-art of soft robotics to assist mobility: a review of physiotherapist and patient identified limitations of current lower-limb exoskeletons and the potential soft-robotic solutions

Background: Soft, wearable, powered exoskeletons are novel devices that may assist rehabilitation, allowing users to walk further or carry out activities of daily living. However, soft robotic exoskeletons, and the more commonly used rigid exoskeletons, are not widely adopted clinically. The available evidence highlights a disconnect between the needs of exoskeleton users and the engineers designing devices. This review aimed to explore the literature on physiotherapist and patient perspectives of the longer-standing, and therefore greater evidenced, rigid exoskeleton limitations. It then offered potential solutions to these limitations, including soft robotics, from an engineering standpoint. Methods: A state-of-the-art review was carried out which included both qualitative and quantitative research papers regarding patient and/or physiotherapist perspectives of rigid exoskeletons. Papers were themed and themes formed the review’s framework. Results: Six main themes regarding the limitations of soft exoskeletons were important to physiotherapists and patients: safety; a one-size-fits approach; ease of device use; weight and placement of device; cost of device; and, specific to patients only, appearance of the device. Potential soft-robotics solutions to address these limitations were offered, including compliant actuators, sensors, suit attachments fitting to user’s body, and the use of control algorithms. Conclusions: It is evident that current exoskeletons are not meeting the needs of their users. Solutions to the limitations offered may inform device development. However, the solutions are not infallible and thus further research and development is required

State of the Tropics 2014 report

[Extract] Is life in the Tropics getting better? The landmark State of the Tropics 2014 Report addresses this nominally simple question. It provides the first in-depth, objective assessment of the Tropics as an environmental and geopolitical entity in its own right. Drawing on the knowledge, experience and diverse backgrounds of leading institutions across the Tropics the report assesses the state of the region and examines the implications of the immense changes the region is experiencing. The assessment demonstrates that nations in the Tropics have made extraordinary progress across a wide range of environmental, social and economic indicators in recent decades. Rapid population and economic growth mean its influence is set to rise dramatically in coming decades. The nature of this influence will depend on how the region addresses its many challenges, and whether it realises its potential and opportunities. The report provides a basis from which to work towards a prosperous, sustainable and equitable future for the Tropics and will be a valuable resource for policy makers, geopolitical analysts, researchers, students and other stakeholders interested in the Tropics